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Sample records for additional experiments revealed

  1. Kinetics of the addition of olefins to Si-centered radicals: the critical role of dispersion interactions revealed by theory and experiment.

    PubMed

    Johnson, Erin R; Clarkin, Owen J; Dale, Stephen G; DiLabio, Gino A

    2015-06-04

    Solution-phase rate constants for the addition of selected olefins to the triethylsilyl and tris(trimethylsilyl)silyl radicals are measured using laser-flash photolysis and competition kinetics. The results are compared with predictions from density functional theory (DFT) calculations, both with and without dispersion corrections obtained from the exchange-hole dipole moment (XDM) model. Without a dispersion correction, the rate constants are consistently underestimated; the errors increase with system size, up to 10(6) s(-1) for the largest system considered. Dispersion interactions preferentially stabilize the transition states relative to the separated reactants and bring the DFT-calculated rate constants into excellent agreement with experiment. Thus, dispersion interactions are found to play a key role in determining the kinetics for addition reactions, particularly those involving sterically bulky functional groups.

  2. Revealing a Child's Pathology: Physicians' Experiences

    ERIC Educational Resources Information Center

    Scelles, Regine; Aubert-Godard, Anne; Gargiulo, Marcela; Avant, Monique; Gortais, Jean

    2010-01-01

    In this study, 12 physicians and 12 care-givers were interviewed using semi-structured interviews. We explored physicians' experiences when they revealed a diagnosis. We also tried to understand which family members the physician was thinking of, with whom they identified themselves, and their first choice of the person to whom they prefer to…

  3. Survey reveals physicians' experiences with cults.

    PubMed

    Lottick, E A

    1993-02-01

    In late June 1992, a stratified random sample of Pennsylvania physicians (5,400) were mailed a two-page questionnaire asking about experiences with destructive cults, either personal, professional, or both. Professional experience was defined as "with patients or their families," and personal experience was defined as "with self, family, or friends." The survey sample group was drawn from primary care physicians (family practice, general practice, internal medicine, and pediatrics) and psychiatrists. Surveys were returned by 1,396 participants, a 26 percent rate of return. A number of the returned surveys (173) included personal observations and comments.

  4. Polymer Photooxidation: An Experiment to Demonstrate the Effect of Additives.

    ERIC Educational Resources Information Center

    Allen, Norman S.; McKellar, John F.

    1979-01-01

    This undergraduate experiment shows that the inclusion of an appropriate additive can have a very marked effect on the physical properties of a polymer. The polymer used is polypropylene and the additives are 2-hydroxy-4-octyloxy-benzophenone and benzophenone. (BB)

  5. Statpipe experience reveals techniques for seabed problems

    SciTech Connect

    Lund, S.; Gjertveit, E.

    1986-04-28

    Design and construction problems posed by severe permanent seabed irregularities along the Statpipe route in the North Sea required careful route planning to avoid pipeline damage and extensive intervention work later. Experiences from the Statpipe project will prove useful for future pipeline construction on the Norwegian Shelf where even more severe seabed irregularities lie north of 62/sup 0/ N. This first of two articles categorizes the major seabed irregularities encountered and recounts design approaches to solving consequent pipelay problems. The Statpipe pipeline system consists of four pipeline legs and totals 842-km subsea and 40-km onshore lines. Two pipelines cross the Norwegian Trench at about 300 m water depth: a 289-km, 30-in. line from Statfjord to the landfall at Kalsto, and a 208-km, 28-in. line from Kalsto to riser platform 16/11S in block 16/11. One 155-km, 36-in. pipeline goes from Heimdal field to 16/11S, and another 191-km, 36-in. line links 16/11S to riser platform 2/4S which is bridge-connected to the Ekofisk field complex. The two 36-in. lines and parts of the 30-in. and 28-in. lines are laid on the North Sea Plateau, west of the Norwegian Trench, in relatively shallow water (70-150 m) on a regular seabed. These represent traditional North Sea pipeline problems only. On the other hand, the two lines crossing the Norwegian Trench have been a challenge both because of the water depth and because of the wide areas of severe seabed irregularities.

  6. Cryptic biodiversity effects: importance of functional redundancy revealed through addition of food web complexity.

    PubMed

    Philpott, Stacy M; Pardee, Gabriella L; Gonthier, David J

    2012-05-01

    Interactions between predators and the degree of functional redundancy among multiple predator species may determine whether herbivores experience increased or decreased predation risk. Specialist parasites can modify predator behavior, yet rarely have cascading effects on multiple predator species and prey been evaluated. We examined influences of specialist phorid parasites (Pseudacteon spp.) on three predatory ant species and herbivores in a coffee agroecosystem. Specifically, we examined whether changes in ant richness affected fruit damage by the coffee berry borer (Hypothenemus hampei) and whether phorids altered multi-predator effects. Each ant species reduced borer damage, and without phorids, increasing predator richness did not further decrease borer damage. However, with phorids, activity of one ant species was reduced, indicating that the presence of multiple ant species was necessary to limit borer damage. In addition, phorid presence revealed synergistic effects of multiple ant species, not observed without the presence of this parasite. Thus, a trait-mediated cascade resulting from a parasite-induced predator behavioral change revealed the importance of functional redundancy, predator diversity, and food web complexity for control of this important pest.

  7. Effects of an additional dimension in the Young experiment

    SciTech Connect

    Barros, Allan Kardec

    2015-09-15

    The results of the Young experiment can be analyzed either by classical or Quantum Physics. The later one though leads to a more complete interpretation, based on two different patterns that appear when one works either with single or double slits. Here we show that the two patterns can be derived from a single principle, in the context of General Relativity, if one assumes an additional spatial dimension to the four known today. The found equations yield the same results as those in Quantum Mechanics.

  8. [Elderly women: revealing their experiences and care needs].

    PubMed

    Merighi, Miriam Aparecida Barbosa; de Oliveira, Deíse Moura; de Jesus, Maria Cristina Pinto; Souto, Rafaella Queiroga; Thamada, Andressa Akina

    2013-04-01

    This qualitative study used a social phenomenology approach to elucidate the experiences, care needs and expectations of the elderly women. Nine elderly women were interviewed between February and May 2011 using a semi-structured questionnaire. The elderly women referred to their physical, mental, and social limitations. They valued ​​the preservation of their autonomy in daily activities and in self-care and considered their families to be a fundamental support. They had expectations of remaining healthy, pursuing leisure activities, and having improved access to healthcare information and treatment. The absence of prospects at this stage of life was related to the loss of significant people and the loss of health. The results of this study reveal important aspects of the experiences of elderly women and encourage further research and improvement in teaching, clinical practice and management policies in relation to the needs of these women.

  9. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  10. Software reliability: Additional investigations into modeling with replicated experiments

    NASA Technical Reports Server (NTRS)

    Nagel, P. M.; Schotz, F. M.; Skirvan, J. A.

    1984-01-01

    The effects of programmer experience level, different program usage distributions, and programming languages are explored. All these factors affect performance, and some tentative relational hypotheses are presented. An analytic framework for replicated and non-replicated (traditional) software experiments is presented. A method of obtaining an upper bound on the error rate of the next error is proposed. The method was validated empirically by comparing forecasts with actual data. In all 14 cases the bound exceeded the observed parameter, albeit somewhat conservatively. Two other forecasting methods are proposed and compared to observed results. Although demonstrated relative to this framework that stages are neither independent nor exponentially distributed, empirical estimates show that the exponential assumption is nearly valid for all but the extreme tails of the distribution. Except for the dependence in the stage probabilities, Cox's model approximates to a degree what is being observed.

  11. Initiation of a thrust fault revealed by analog experiments

    NASA Astrophysics Data System (ADS)

    Dotare, Tatsuya; Yamada, Yasuhiro; Adam, Juergen; Hori, Takane; Sakaguchi, Hide

    2016-08-01

    To reveal in detail the process of initiation of a thrust fault, we conducted analog experiments with dry quartz sand using a high-resolution digital image correlation technique to identify minor shear-strain patterns for every 27 μm of shortening (with an absolute displacement accuracy of 0.5 μm). The experimental results identified a number of "weak shear bands" and minor uplift prior to the initiation of a thrust in cross-section view. The observations suggest that the process is closely linked to the activity of an adjacent existing thrust, and can be divided into three stages. Stage 1 is characterized by a series of abrupt and short-lived weak shear bands at the location where the thrust will subsequently be generated. The area that will eventually be the hanging wall starts to uplift before the fault forms. The shear strain along the existing thrust decreases linearly during this stage. Stage 2 is defined by the generation of the new thrust and active displacements along it, identified by the shear strain along the thrust. The location of the new thrust may be constrained by its back-thrust, generally produced at the foot of the surface slope. The activity of the existing thrust falls to zero once the new thrust is generated, although these two events are not synchronous. Stage 3 of the thrust is characterized by a constant displacement that corresponds to the shortening applied to the model. Similar minor shear bands have been reported in the toe area of the Nankai accretionary prism, SW Japan. By comparing several transects across this subduction margin, we can classify the lateral variations in the structural geometry into the same stages of deformation identified in our experiments. Our findings may also be applied to the evaluation of fracture distributions in thrust belts during unconventional hydrocarbon exploration and production.

  12. Initiation process of a thrust fault revealed by analog experiments

    NASA Astrophysics Data System (ADS)

    Yamada, Yasuhiro; Dotare, Tatsuya; Adam, Juergen; Hori, Takane; Sakaguchi, Hide

    2016-04-01

    We conducted 2D (cross-sectional) analog experiments with dry sand using a high resolution digital image correlation (DIC) technique to reveal initiation process of a thrust fault in detail, and identified a number of "weak shear bands" and minor uplift prior to the thrust initiation. The observations suggest that the process can be divided into three stages. Stage 1: characterized by a series of abrupt and short-lived weak shear bands at the location where the thrust will be generated later. Before initiation of the fault, the area to be the hanging wall starts to uplift. Stage 2: defined by the generation of the new thrust and its active displacement. The location of the new thrust seems to be constrained by its associated back-thrust, produced at the foot of the surface slope (by the previous thrust). The activity of the previous thrust turns to zero once the new thrust is generated, but the timing of these two events is not the same. Stage 3: characterized by a constant displacement along the (new) thrust. Similar minor shear bands can be seen in the toe area of the Nankai accretionary prism, SW Japan and we can correlate the along-strike variations in seismic profiles to the model results that show the characteristic features in each thrust development stage.

  13. Maturation experiments reveal bias in the fossil record of feathers

    NASA Astrophysics Data System (ADS)

    McNamara, Maria; Field, Daniel

    2016-04-01

    The evolutionary history of birds and feathers is a major focus in palaeobiology and evolutionary biology. Diverse exceptionally preserved birds and feathered dinosaurs from Jurassic and Cretaceous biotas in China have provided pivotal evidence of early feathers and feather-like integumentary features, but the true nature of many of these fossil soft tissues is still debated. Interpretations of feathers at intermediate developmental stages (i.e. Stages II, III and IV) and of simple quill-like (Stage I) feathers are particularly controversial. This reflects key uncertainties relating to the preservation potential of feathers at different evolutionary-developmental stages, and to the relative preservation potential of diagnostic features of Stage I feathers and hair. To resolve these issues, we used high pressure-high temperature autoclave experiments to simulate the effects of burial on modern feathers from the Black Coucal (Centropus grilii) and Common Starling (Sturnus vulgaris), and on human hair. Our results reveal profound differences in the recalcitrance of feathers of different types during maturation: Stage I and Stage V feathers retain diagnostic morphological and ultrastructural details following maturation, whereas other feather types do not. Further, the morphology and arrangement of certain ultrastructural features diagnostic of Stages III and IV, e.g. barbules, are preferentially lost during maturation. These results indicate a pervasive bias in the fossil record of feathers, whereby preservation of feathers at Stages I and V is favored. Critical stages in the evolution of feathers, i.e. Stages II, III and IV, are less likely to be preserved and more likely to be misinterpreted as feathers at earlier developmental stages. Our discovery has major implications for our understanding of the fidelity of the fossil record of feathers and provides a framework for testing the significance of putative examples of fossil feathers at different developmental

  14. When Values and Behaviors Conflict: Immigrant BSW Students' Experiences Revealed

    ERIC Educational Resources Information Center

    Calderwood, Kimberly; Harper, Kim; Ball, Kellie; Liang, David

    2009-01-01

    This qualitative study reveals the discomfort seven immigrant bachelor of social work students reported experiencing when the behaviors expected of them as Canadian social workers conflicted with their fundamental family values. Behaviorally, participants had assimilated to Canadian and to social work cultures; however, the values they held from…

  15. The importance of taxonomic resolution for additive beta diversity as revealed through DNA barcoding.

    PubMed

    Bringloe, Trevor T; Cottenie, Karl; Martin, Gillian K; Adamowicz, Sarah J

    2016-12-01

    Additive diversity partitioning (α, β, and γ) is commonly used to study the distribution of species-level diversity across spatial scales. Here, we first investigate whether published studies of additive diversity partitioning show signs of difficulty attaining species-level resolution due to inherent limitations with morphological identifications. Second, we present a DNA barcoding approach to delineate specimens of stream caddisfly larvae (order Trichoptera) and consider the importance of taxonomic resolution on classical (additive) measures of beta (β) diversity. Caddisfly larvae were sampled using a hierarchical spatial design in two regions (subarctic Churchill, Manitoba, Canada; temperate Pennsylvania, USA) and then additively partitioned according to Barcode Index Numbers (molecular clusters that serve as a proxy for species), genus, and family levels; diversity components were expressed as proportional species turnover. We screened 114 articles of additive diversity partitioning and found that a third reported difficulties with achieving species-level identifications, with a clear taxonomic tendency towards challenges identifying invertebrate taxa. Regarding our own study, caddisfly BINs appeared to show greater subregional turnover (e.g., proportional additive β) compared to genus or family levels. Diversity component studies failing to achieve species resolution due to morphological identifications may therefore be underestimating diversity turnover at larger spatial scales.

  16. Traffic Experiment Reveals the Nature of Car-Following

    PubMed Central

    Jiang, Rui; Hu, Mao-Bin; Zhang, H. M.; Gao, Zi-You; Jia, Bin; Wu, Qing-Song; Wang, Bing; Yang, Ming

    2014-01-01

    As a typical self-driven many-particle system far from equilibrium, traffic flow exhibits diverse fascinating non-equilibrium phenomena, most of which are closely related to traffic flow stability and specifically the growth/dissipation pattern of disturbances. However, the traffic theories have been controversial due to a lack of precise traffic data. We have studied traffic flow from a new perspective by carrying out large-scale car-following experiment on an open road section, which overcomes the intrinsic deficiency of empirical observations. The experiment has shown clearly the nature of car-following, which runs against the traditional traffic flow theory. Simulations show that by removing the fundamental notion in the traditional car-following models and allowing the traffic state to span a two-dimensional region in velocity-spacing plane, the growth pattern of disturbances has changed qualitatively and becomes qualitatively or even quantitatively in consistent with that observed in the experiment. PMID:24740284

  17. Traffic experiment reveals the nature of car-following.

    PubMed

    Jiang, Rui; Hu, Mao-Bin; Zhang, H M; Gao, Zi-You; Jia, Bin; Wu, Qing-Song; Wang, Bing; Yang, Ming

    2014-01-01

    As a typical self-driven many-particle system far from equilibrium, traffic flow exhibits diverse fascinating non-equilibrium phenomena, most of which are closely related to traffic flow stability and specifically the growth/dissipation pattern of disturbances. However, the traffic theories have been controversial due to a lack of precise traffic data. We have studied traffic flow from a new perspective by carrying out large-scale car-following experiment on an open road section, which overcomes the intrinsic deficiency of empirical observations. The experiment has shown clearly the nature of car-following, which runs against the traditional traffic flow theory. Simulations show that by removing the fundamental notion in the traditional car-following models and allowing the traffic state to span a two-dimensional region in velocity-spacing plane, the growth pattern of disturbances has changed qualitatively and becomes qualitatively or even quantitatively in consistent with that observed in the experiment.

  18. Eye Movements Reveal Readers' Lexical Quality and Reading Experience

    ERIC Educational Resources Information Center

    Taylor, Jessica Nelson; Perfetti, Charles A.

    2016-01-01

    Two experiments demonstrate that individual differences among normal adult readers, including lexical quality, are expressed in silent reading at the word level. In the first of two studies we identified major dimensions of variability among college readers and among words using factor analysis. We then examined the effects of these dimensions of…

  19. Separateness Representations in a Sculpting Task: Revealing Maternal Subjective Experience

    ERIC Educational Resources Information Center

    Bat Or, Michal

    2015-01-01

    This study explored mothers' separateness representations via a clay sculpting task assigned to 24 mothers of preschool children aged 21 months to 4 years. Each participant created a clay sculpture of herself and her child, followed by a semi-structured interview about the sculpting experience and the meaning of the sculpture. Qualitative analyses…

  20. Absorption Reveals and Hydrogen Addition Explains New Interstellar Aldehydes: Propenal and Propanal

    NASA Technical Reports Server (NTRS)

    Hollis, J. M.; Jewell, P. R.; Lovas, F. J.; Remijan, A.; Mollendal, H.

    2004-01-01

    New interstellar molecules propenal (CH2CHCHO) and propanal (CH3CH2CHO) have been detected largely in absorption toward the star-forming region Sagittarius B2(N) by means of rotational transitions observed with the 100-m Green Bank Telescope (GBT) operating in the range of 18 GHz (lambda approximately 1.7 cm) to 26 GHz (lambda approximately 1.2 cm). The GBT was also used to observe the previously reported interstellar aldehyde propynal (HC2CHO) in Sagittarius B2(N) which is known for large molecules believed to form on interstellar grains. The presence of these three interstellar aldehydes toward Sagittarius B2(N) strongly suggests that simple hydrogen addition on interstellar grains accounts for successively larger molecular species: from propynal to propenal and from propenal to propanal. Energy sources within Sagittarius B2(N) likely permit the hydrogen addition reactions on grain surfaces to proceed. This work demonstrates that successive hydrogen addition is probably an important chemistry route in the formation of a number of complex interstellar molecules. We also searched for but did not detect the three-carbon sugar glyceraldehyde (CH2OHCHOHCHO).

  1. Neural correlates of the LSD experience revealed by multimodal neuroimaging.

    PubMed

    Carhart-Harris, Robin L; Muthukumaraswamy, Suresh; Roseman, Leor; Kaelen, Mendel; Droog, Wouter; Murphy, Kevin; Tagliazucchi, Enzo; Schenberg, Eduardo E; Nest, Timothy; Orban, Csaba; Leech, Robert; Williams, Luke T; Williams, Tim M; Bolstridge, Mark; Sessa, Ben; McGonigle, John; Sereno, Martin I; Nichols, David; Hellyer, Peter J; Hobden, Peter; Evans, John; Singh, Krish D; Wise, Richard G; Curran, H Valerie; Feilding, Amanda; Nutt, David J

    2016-04-26

    Lysergic acid diethylamide (LSD) is the prototypical psychedelic drug, but its effects on the human brain have never been studied before with modern neuroimaging. Here, three complementary neuroimaging techniques: arterial spin labeling (ASL), blood oxygen level-dependent (BOLD) measures, and magnetoencephalography (MEG), implemented during resting state conditions, revealed marked changes in brain activity after LSD that correlated strongly with its characteristic psychological effects. Increased visual cortex cerebral blood flow (CBF), decreased visual cortex alpha power, and a greatly expanded primary visual cortex (V1) functional connectivity profile correlated strongly with ratings of visual hallucinations, implying that intrinsic brain activity exerts greater influence on visual processing in the psychedelic state, thereby defining its hallucinatory quality. LSD's marked effects on the visual cortex did not significantly correlate with the drug's other characteristic effects on consciousness, however. Rather, decreased connectivity between the parahippocampus and retrosplenial cortex (RSC) correlated strongly with ratings of "ego-dissolution" and "altered meaning," implying the importance of this particular circuit for the maintenance of "self" or "ego" and its processing of "meaning." Strong relationships were also found between the different imaging metrics, enabling firmer inferences to be made about their functional significance. This uniquely comprehensive examination of the LSD state represents an important advance in scientific research with psychedelic drugs at a time of growing interest in their scientific and therapeutic value. The present results contribute important new insights into the characteristic hallucinatory and consciousness-altering properties of psychedelics that inform on how they can model certain pathological states and potentially treat others.

  2. Neural correlates of the LSD experience revealed by multimodal neuroimaging

    PubMed Central

    Carhart-Harris, Robin L.; Muthukumaraswamy, Suresh; Roseman, Leor; Kaelen, Mendel; Droog, Wouter; Murphy, Kevin; Tagliazucchi, Enzo; Schenberg, Eduardo E.; Nest, Timothy; Orban, Csaba; Leech, Robert; Williams, Luke T.; Williams, Tim M.; Bolstridge, Mark; Sessa, Ben; McGonigle, John; Sereno, Martin I.; Nichols, David; Hobden, Peter; Evans, John; Singh, Krish D.; Wise, Richard G.; Curran, H. Valerie; Feilding, Amanda; Nutt, David J.

    2016-01-01

    Lysergic acid diethylamide (LSD) is the prototypical psychedelic drug, but its effects on the human brain have never been studied before with modern neuroimaging. Here, three complementary neuroimaging techniques: arterial spin labeling (ASL), blood oxygen level-dependent (BOLD) measures, and magnetoencephalography (MEG), implemented during resting state conditions, revealed marked changes in brain activity after LSD that correlated strongly with its characteristic psychological effects. Increased visual cortex cerebral blood flow (CBF), decreased visual cortex alpha power, and a greatly expanded primary visual cortex (V1) functional connectivity profile correlated strongly with ratings of visual hallucinations, implying that intrinsic brain activity exerts greater influence on visual processing in the psychedelic state, thereby defining its hallucinatory quality. LSD’s marked effects on the visual cortex did not significantly correlate with the drug’s other characteristic effects on consciousness, however. Rather, decreased connectivity between the parahippocampus and retrosplenial cortex (RSC) correlated strongly with ratings of “ego-dissolution” and “altered meaning,” implying the importance of this particular circuit for the maintenance of “self” or “ego” and its processing of “meaning.” Strong relationships were also found between the different imaging metrics, enabling firmer inferences to be made about their functional significance. This uniquely comprehensive examination of the LSD state represents an important advance in scientific research with psychedelic drugs at a time of growing interest in their scientific and therapeutic value. The present results contribute important new insights into the characteristic hallucinatory and consciousness-altering properties of psychedelics that inform on how they can model certain pathological states and potentially treat others. PMID:27071089

  3. Generalized additive models reveal the intrinsic complexity of wood formation dynamics.

    PubMed

    Cuny, Henri E; Rathgeber, Cyrille B K; Kiessé, Tristan Senga; Hartmann, Felix P; Barbeito, Ignacio; Fournier, Meriem

    2013-04-01

    The intra-annual dynamics of wood formation, which involves the passage of newly produced cells through three successive differentiation phases (division, enlargement, and wall thickening) to reach the final functional mature state, has traditionally been described in conifers as three delayed bell-shaped curves followed by an S-shaped curve. Here the classical view represented by the 'Gompertz function (GF) approach' was challenged using two novel approaches based on parametric generalized linear models (GLMs) and 'data-driven' generalized additive models (GAMs). These three approaches (GFs, GLMs, and GAMs) were used to describe seasonal changes in cell numbers in each of the xylem differentiation phases and to calculate the timing of cell development in three conifer species [Picea abies (L.), Pinus sylvestris L., and Abies alba Mill.]. GAMs outperformed GFs and GLMs in describing intra-annual wood formation dynamics, showing two left-skewed bell-shaped curves for division and enlargement, and a right-skewed bimodal curve for thickening. Cell residence times progressively decreased through the season for enlargement, whilst increasing late but rapidly for thickening. These patterns match changes in cell anatomical features within a tree ring, which allows the separation of earlywood and latewood into two distinct cell populations. A novel statistical approach is presented which renews our understanding of xylogenesis, a dynamic biological process in which the rate of cell production interplays with cell residence times in each developmental phase to create complex seasonal patterns.

  4. Gas Chromatographic Determination of Methyl Salicylate in Rubbing Alcohol: An Experiment Employing Standard Addition.

    ERIC Educational Resources Information Center

    Van Atta, Robert E.; Van Atta, R. Lewis

    1980-01-01

    Provides a gas chromatography experiment that exercises the quantitative technique of standard addition to the analysis for a minor component, methyl salicylate, in a commercial product, "wintergreen rubbing alcohol." (CS)

  5. Traveling-wave Ion Mobility-Mass Spectrometry Reveals Additional Mechanistic Details in the Stabilization of Protein Complex Ions through Tuned Salt Additives

    PubMed Central

    Han, Linjie; Ruotolo, Brandon T.

    2013-01-01

    Ion mobility–mass spectrometry is often applied to the structural elucidation of multiprotein assemblies in cases where X-ray crystallography or NMR experiments have proved challenging. Such applications are growing steadily as we continue to probe regions of the proteome that are less-accessible to such high-resolution structural biology tools. Since ion mobility measures protein structure in the absence of bulk solvent, strategies designed to more-broadly stabilize native-like protein structures in the gas-phase would greatly enable the application of such measurements to challenging structural targets. Recently, we have begun investigating the ability of salt-based solution additives that remain bound to protein ions in the gas-phase to stabilize native-like protein structures. These experiments, which utilize collision induced unfolding and collision induced dissociation in a tandem mass spectrometry mode to measure protein stability, seek to develop a rank-order similar to the Hofmeister series that categorizes the general ability of different anions and cations to stabilize gas-phase protein structure. Here, we study magnesium chloride as a potential stabilizing additive for protein structures in vacuo, and find that the addition of this salt to solutions prior to nano-electrospray ionization dramatically enhances multiprotein complex structural stability in the gas-phase. Based on these experiments, we also refine the physical mechanism of cation-based protein complex ion stabilization by tracking the unfolding transitions experienced by cation-bound complexes. Upon comparison with unbound proteins, we find strong evidence that stabilizing cations act to tether protein complex structure. We conclude by putting the results reported here in context, and by projecting the future applications of this method. PMID:23539363

  6. Active dentate granule cells encode experience to promote the addition of adult-born hippocampal neurons.

    PubMed

    Kirschen, Gregory W; Shen, Jia; Tian, Mu; Schroeder, Bryce; Wang, Jia; Man, Guoming; Wu, Song; Ge, Shaoyu

    2017-04-03

    The continuous addition of new dentate granule cells, exquisitely regulated by brain activity, renders the hippocampus plastic. However, how neural circuits encode experiences to impact the addition of adult-born neurons remains unknown. Here, we used endoscopic Ca(2+) imaging to track the real-time activity of individual dentate granule cells in freely-behaving mice. For the first time, we found that active dentate granule cells responded to a novel experience by preferentially increasing their Ca(2+) event frequency. This elevated activity, which we found to be associated with object exploration, returned to baseline by one hour in the same environment, but could be dishabituated via introduction to a novel environment. To seamlessly transition between environments, we next established a freely-controllable virtual reality system for unrestrained mice. We again observed increased firing of active neurons in a virtual enriched environment. Interestingly, multiple novel virtual experiences accumulatively increased the number of newborn neurons when compared to a single experience. Finally, optogenetic silencing of existing dentate granule cells during novel environmental exploration perturbed experience-induced neuronal addition. Together, our study shows that the adult brain conveys novel, enriched experiences to increase the addition of adult-born hippocampal neurons by increasing the firing of active dentate granule cells.SIGNIFICANCE STATEMENTAdult brains are constantly reshaping themselves from synapses to circuits as we encounter novel experiences from moment to moment. Importantly, this reshaping includes the addition of newborn hippocampal neurons. However, it remains largely unknown how our circuits encode experience-induced brain activity to govern the addition of new hippocampal neurons. By coupling in vivo Ca(2+) imaging of dentate granule neurons with a novel unrestrained virtual reality system for rodents, we discovered that a new experience rapidly

  7. Response of non-added solutes during nutrient addition experiments in streams

    NASA Astrophysics Data System (ADS)

    Rodriguez-Cardona, B.; Wymore, A.; Koenig, L.; Coble, A. A.; McDowell, W. H.

    2015-12-01

    Nutrient addition experiments, such as Tracer Additions for Spiraling Curve Characterization (TASCC), have become widely popular as a means to study nutrient uptake dynamics in stream ecosystems. However, the impact of these additions on ambient concentrations of non-added solutes is often overlooked. TASCC addition experiments are ideal for assessing interactions among solutes because it allows for the characterization of multiple solute concentrations across a broad range of added nutrient concentrations. TASCC additions also require the addition of a conservative tracer (NaCl) to track changes in conductivity during the experimental manipulation. Despite its use as a conservative tracer, chloride (Cl) and its associated sodium (Na) might change the concentrations of other ions and non-added nutrients through ion exchange or other processes. Similarly, additions of biologically active solutes might change the concentrations of other non-added solutes. These methodological issues in nutrient addition experiments have been poorly addressed in the literature. Here we examine the response of non-added solutes to pulse additions (i.e. TASCC) of NaCl plus nitrate (NO3-), ammonium, and phosphate across biomes including temperate and tropical forests, and arctic taiga. Preliminary results demonstrate that non-added solutes respond to changes in the concentration of these added nutrients. For example, concentrations of dissolved organic nitrogen (DON) in suburban headwater streams of New Hampshire both increase and decrease in response to NO3- additions, apparently due to biotic processes. Similarly, cations such as potassium, magnesium, and calcium also increase during TASCC experiments, likely due to cation exchange processes associated with Na addition. The response of non-added solutes to short-term pulses of added nutrients and tracers needs to be carefully assessed to ensure that nutrient uptake metrics are accurate, and to detect biotic interactions that may

  8. Effect of Additives on Green Sand Molding Properties using Design of Experiments and Taguchi's Quality Loss Function - An Experimental Study

    NASA Astrophysics Data System (ADS)

    Desai, Bhagyashree; Mokashi, Pavani; Anand, R. L.; Burli, S. B.; Khandal, S. V.

    2016-09-01

    The experimental study aims to underseek the effect of various additives on the green sand molding properties as a particular combination of additives could yield desired sand properties. The input parameters (factors) selected were water and powder (Fly ash, Coconut shell and Tamarind) in three levels. Experiments were planned using design of experiments (DOE). On the basis of plans, experiments were conducted to understand the behavior of sand mould properties such as compression strength, shear strength, permeability number with various additives. From the experimental results it could be concluded that the factors have significant effect on the sand properties as P-value found to be less than 0.05 for all the cases studied. The optimization based on quality loss function was also performed. The study revealed that the quality loss associated with the tamarind powder was lesser compared to other additives selected for the study. The optimization based on quality loss function and the parametric analysis using ANOVA suggested that the tamarind powder of 8 gm per Kg of molding sand and moisture content of 7% yield better properties to obtain sound castings.

  9. Comparing GWAS Results of Complex Traits Using Full Genetic Model and Additive Models for Revealing Genetic Architecture

    PubMed Central

    Monir, Md. Mamun; Zhu, Jun

    2017-01-01

    Most of the genome-wide association studies (GWASs) for human complex diseases have ignored dominance, epistasis and ethnic interactions. We conducted comparative GWASs for total cholesterol using full model and additive models, which illustrate the impacts of the ignoring genetic variants on analysis results and demonstrate how genetic effects of multiple loci could differ across different ethnic groups. There were 15 quantitative trait loci with 13 individual loci and 3 pairs of epistasis loci identified by full model, whereas only 14 loci (9 common loci and 5 different loci) identified by multi-loci additive model. Again, 4 full model detected loci were not detected using multi-loci additive model. PLINK-analysis identified two loci and GCTA-analysis detected only one locus with genome-wide significance. Full model identified three previously reported genes as well as several new genes. Bioinformatics analysis showed some new genes are related with cholesterol related chemicals and/or diseases. Analyses of cholesterol data and simulation studies revealed that the full model performs were better than the additive-model performs in terms of detecting power and unbiased estimations of genetic variants of complex traits. PMID:28079101

  10. Chemical and biological consequences of using carbon dioxide versus acid additions in ocean acidification experiments

    USGS Publications Warehouse

    Yates, Kimberly K.; DuFore, Christopher M.; Robbins, Lisa L.

    2013-01-01

    Use of different approaches for manipulating seawater chemistry during ocean acidification experiments has confounded comparison of results from various experimental studies. Some of these discrepancies have been attributed to whether addition of acid (such as hydrochloric acid, HCl) or carbon dioxide (CO2) gas has been used to adjust carbonate system parameters. Experimental simulations of carbonate system parameter scenarios for the years 1766, 2007, and 2100 were performed using the carbonate speciation program CO2SYS to demonstrate the variation in seawater chemistry that can result from use of these approaches. Results showed that carbonate system parameters were 3 percent and 8 percent lower than target values in closed-system acid additions, and 1 percent and 5 percent higher in closed-system CO2 additions for the 2007 and 2100 simulations, respectively. Open-system simulations showed that carbonate system parameters can deviate by up to 52 percent to 70 percent from target values in both acid addition and CO2 addition experiments. Results from simulations for the year 2100 were applied to empirically derived equations that relate biogenic calcification to carbonate system parameters for calcifying marine organisms including coccolithophores, corals, and foraminifera. Calculated calcification rates for coccolithophores, corals, and foraminifera differed from rates at target conditions by 0.5 percent to 2.5 percent in closed-system CO2 gas additions, from 0.8 percent to 15 percent in the closed-system acid additions, from 4.8 percent to 94 percent in open-system acid additions, and from 7 percent to 142 percent in open-system CO2 additions.

  11. Additive Routes to Action Learning: Layering Experience Shapes Engagement of the Action Observation Network

    PubMed Central

    Kirsch, Louise P.; Cross, Emily S.

    2015-01-01

    The way in which we perceive others in action is biased by one's prior experience with an observed action. For example, we can have auditory, visual, or motor experience with actions we observe others perform. How action experience via 1, 2, or all 3 of these modalities shapes action perception remains unclear. Here, we combine pre- and post-training functional magnetic resonance imaging measures with a dance training manipulation to address how building experience (from auditory to audiovisual to audiovisual plus motor) with a complex action shapes subsequent action perception. Results indicate that layering experience across these 3 modalities activates a number of sensorimotor cortical regions associated with the action observation network (AON) in such a way that the more modalities through which one experiences an action, the greater the response is within these AON regions during action perception. Moreover, a correlation between left premotor activity and participants' scores for reproducing an action suggests that the better an observer can perform an observed action, the stronger the neural response is. The findings suggest that the number of modalities through which an observer experiences an action impacts AON activity additively, and that premotor cortical activity might serve as an index of embodiment during action observation. PMID:26209850

  12. Additive Routes to Action Learning: Layering Experience Shapes Engagement of the Action Observation Network.

    PubMed

    Kirsch, Louise P; Cross, Emily S

    2015-12-01

    The way in which we perceive others in action is biased by one's prior experience with an observed action. For example, we can have auditory, visual, or motor experience with actions we observe others perform. How action experience via 1, 2, or all 3 of these modalities shapes action perception remains unclear. Here, we combine pre- and post-training functional magnetic resonance imaging measures with a dance training manipulation to address how building experience (from auditory to audiovisual to audiovisual plus motor) with a complex action shapes subsequent action perception. Results indicate that layering experience across these 3 modalities activates a number of sensorimotor cortical regions associated with the action observation network (AON) in such a way that the more modalities through which one experiences an action, the greater the response is within these AON regions during action perception. Moreover, a correlation between left premotor activity and participants' scores for reproducing an action suggests that the better an observer can perform an observed action, the stronger the neural response is. The findings suggest that the number of modalities through which an observer experiences an action impacts AON activity additively, and that premotor cortical activity might serve as an index of embodiment during action observation.

  13. Analysis of biostimulated microbial communities from two field experiments reveals temporal and spatial differences in proteome profiles

    SciTech Connect

    Callister, S.J.; Wilkins, M.J.; Nicora, C.D.; Williams, K.H.; Banfield, J.F.; VerBerkmoes, N.C.; Hettich, R.L.; NGuessan, A.L.; Mouser, P.J.; Elifantz, H.; Smith, R.D.; Lovley, D.R.; Lipton, M.S.; Long, P.E.

    2010-07-15

    Stimulated by an acetate-amendment field experiment conducted in 2007, anaerobic microbial populations in the aquifer at the Rifle Integrated Field Research Challenge site in Colorado reduced mobile U(VI) to insoluble U(IV). During this experiment, planktonic biomass was sampled at various time points to quantitatively evaluate proteomes. In 2008, an acetate-amended field experiment was again conducted in a similar manner to the 2007 experiment. As there was no comprehensive metagenome sequence available for use in proteomics analysis, we systematically evaluated 12 different organism genome sequences to generate sets of aggregate genomes, or “pseudo-metagenomes”, for supplying relative quantitative peptide and protein identifications. Proteomics results support previous observations of the dominance of Geobacteraceae during biostimulation using acetate as sole electron donor, and revealed a shift from an early stage of iron reduction to a late stage of iron reduction. Additionally, a shift from iron reduction to sulfate reduction was indicated by changes in the contribution of proteome information contributed by different organism genome sequences within the aggregate set. In addition, the comparison of proteome measurements made between the 2007 field experiment and 2008 field experiment revealed differences in proteome profiles. These differences may be the result of alterations in abundance and population structure within the planktonic biomass samples collected for analysis.

  14. Goodness-of-fit methods for additive-risk models in tumorigenicity experiments.

    PubMed

    Ghosh, Debashis

    2003-09-01

    In tumorigenicity experiments, a complication is that the time to event is generally not observed, so that the time to tumor is subject to interval censoring. One of the goals in these studies is to properly model the effect of dose on risk. Thus, it is important to have goodness of fit procedures available for assessing the model fit. While several estimation procedures have been developed for current-status data, relatively little work has been done on model-checking techniques. In this article, we propose numerical and graphical methods for the analysis of current-status data using the additive-risk model, primarily focusing on the situation where the monitoring times are dependent. The finite-sample properties of the proposed methodology are examined through numerical studies. The methods are then illustrated with data from a tumorigenicity experiment.

  15. Spinel dissolution via addition of glass forming chemicals. Results of preliminary experiments

    SciTech Connect

    Fox, K. M.; Johnson, F. C.

    2015-11-01

    Increased loading of high level waste in glass can lead to crystallization within the glass. Some crystalline species, such as spinel, have no practical impact on the chemical durability of the glass, and therefore may be acceptable from both a processing and a product performance standpoint. In order to operate a melter with a controlled amount of crystallization, options must be developed for remediating an unacceptable accumulation of crystals. This report describes preliminary experiments designed to evaluate the ability to dissolve spinel crystals in simulated waste glass melts via the addition of glass forming chemicals (GFCs).

  16. Supra-additive contribution of shape and surface information to individual face discrimination as revealed by fast periodic visual stimulation.

    PubMed

    Dzhelyova, Milena; Rossion, Bruno

    2014-12-24

    Face perception depends on two main sources of information--shape and surface cues. Behavioral studies suggest that both of them contribute roughly equally to discrimination of individual faces, with only a small advantage provided by their combination. However, it is difficult to quantify the respective contribution of each source of information to the visual representation of individual faces with explicit behavioral measures. To address this issue, facial morphs were created that varied in shape only, surface only, or both. Electrocephalogram (EEG) were recorded from 10 participants during visual stimulation at a fast periodic rate, in which the same face was presented four times consecutively and the fifth face (the oddball) varied along one of the morphed dimensions. Individual face discrimination was indexed by the periodic EEG response at the oddball rate (e.g., 5.88 Hz/5 = 1.18 Hz). While shape information was discriminated mainly at right occipitotemporal electrode sites, surface information was coded more bilaterally and provided a larger response overall. Most importantly, shape and surface changes alone were associated with much weaker responses than when both sources of information were combined in the stimulus, revealing a supra-additive effect. These observations suggest that the two kinds of information combine nonlinearly to provide a full individual face representation, face identity being more than the sum of the contribution of shape and surface cues.

  17. Additional experiments relative to the shelf life of Li(Si)/FeS2 thermal batteries

    NASA Astrophysics Data System (ADS)

    Searcy, J. Q.; Armijo, J. R.

    1985-02-01

    A continuing effort to develop a new thermal battery technology based on the Li(Si)/FeS2 electrochemical couple is reported. The results relate to the long shelf life requirement for thermal batteries designed by Sandia, and include topics relevant to leakage through the hermetic seal and accelerated aging experiments with materials new to the technology. Conclusions relevant to leakage through the hermetic seal are that the maximum leak rate must not exceed 1.8 x 10(-7) w, where w is the grams of Li(Si) contained by a battery, and that a bomb type leak test can be designed that is adequate for most Li(Si)/FeS2 batteries. Conclusions relevant to long term compatibility of new materials include the following: nickel is not compatible with the iron disulfide in the cathode; the CaSi2 additive used to suppress the initial voltage transient does not react or degrade during accelerated aging experiments, but the use of that material can lead to an increase in the variability of the activated lives, especially for long life batteries; Grafoil current collectors used with the cathode do not degrade in accelerated aging experiments.

  18. Genomic Analysis Reveals Novel Diversity among the 1976 Philadelphia Legionnaires’ Disease Outbreak Isolates and Additional ST36 Strains

    PubMed Central

    Mercante, Jeffrey W.; Morrison, Shatavia S.; Desai, Heta P.; Raphael, Brian H.; Winchell, Jonas M.

    2016-01-01

    Legionella pneumophila was first recognized as a cause of severe and potentially fatal pneumonia during a large-scale outbreak of Legionnaires’ disease (LD) at a Pennsylvania veterans’ convention in Philadelphia, 1976. The ensuing investigation and recovery of four clinical isolates launched the fields of Legionella epidemiology and scientific research. Only one of the original isolates, “Philadelphia-1”, has been widely distributed or extensively studied. Here we describe the whole-genome sequencing (WGS), complete assembly, and comparative analysis of all Philadelphia LD strains recovered from that investigation, along with L. pneumophila isolates sharing the Philadelphia sequence type (ST36). Analyses revealed that the 1976 outbreak was due to multiple serogroup 1 strains within the same genetic lineage, differentiated by an actively mobilized, self-replicating episome that is shared with L. pneumophila str. Paris, and two large, horizontally-transferred genomic loci, among other polymorphisms. We also found a completely unassociated ST36 strain that displayed remarkable genetic similarity to the historical Philadelphia isolates. This similar strain implies the presence of a potential clonal population, and suggests important implications may exist for considering epidemiological context when interpreting phylogenetic relationships among outbreak-associated isolates. Additional extensive archival research identified the Philadelphia isolate associated with a non-Legionnaire case of “Broad Street pneumonia”, and provided new historical and genetic insights into the 1976 epidemic. This retrospective analysis has underscored the utility of fully-assembled WGS data for Legionella outbreak investigations, highlighting the increased resolution that comes from long-read sequencing and a sequence type-matched genomic data set. PMID:27684472

  19. Revealing the Earth's mantle from the tallest mountains using the Jinping Neutrino Experiment.

    PubMed

    Šrámek, Ondřej; Roskovec, Bedřich; Wipperfurth, Scott A; Xi, Yufei; McDonough, William F

    2016-09-09

    The Earth's engine is driven by unknown proportions of primordial energy and heat produced in radioactive decay. Unfortunately, competing models of Earth's composition reveal an order of magnitude uncertainty in the amount of radiogenic power driving mantle dynamics. Recent measurements of the Earth's flux of geoneutrinos, electron antineutrinos from terrestrial natural radioactivity, reveal the amount of uranium and thorium in the Earth and set limits on the residual proportion of primordial energy. Comparison of the flux measured at large underground neutrino experiments with geologically informed predictions of geoneutrino emission from the crust provide the critical test needed to define the mantle's radiogenic power. Measurement at an oceanic location, distant from nuclear reactors and continental crust, would best reveal the mantle flux, however, no such experiment is anticipated. We predict the geoneutrino flux at the site of the Jinping Neutrino Experiment (Sichuan, China). Within 8 years, the combination of existing data and measurements from soon to come experiments, including Jinping, will exclude end-member models at the 1σ level, define the mantle's radiogenic contribution to the surface heat loss, set limits on the composition of the silicate Earth, and provide significant parameter bounds for models defining the mode of mantle convection.

  20. Revealing the Earth’s mantle from the tallest mountains using the Jinping Neutrino Experiment

    NASA Astrophysics Data System (ADS)

    Šrámek, Ondřej; Roskovec, Bedřich; Wipperfurth, Scott A.; Xi, Yufei; McDonough, William F.

    2016-09-01

    The Earth’s engine is driven by unknown proportions of primordial energy and heat produced in radioactive decay. Unfortunately, competing models of Earth’s composition reveal an order of magnitude uncertainty in the amount of radiogenic power driving mantle dynamics. Recent measurements of the Earth’s flux of geoneutrinos, electron antineutrinos from terrestrial natural radioactivity, reveal the amount of uranium and thorium in the Earth and set limits on the residual proportion of primordial energy. Comparison of the flux measured at large underground neutrino experiments with geologically informed predictions of geoneutrino emission from the crust provide the critical test needed to define the mantle’s radiogenic power. Measurement at an oceanic location, distant from nuclear reactors and continental crust, would best reveal the mantle flux, however, no such experiment is anticipated. We predict the geoneutrino flux at the site of the Jinping Neutrino Experiment (Sichuan, China). Within 8 years, the combination of existing data and measurements from soon to come experiments, including Jinping, will exclude end-member models at the 1σ level, define the mantle’s radiogenic contribution to the surface heat loss, set limits on the composition of the silicate Earth, and provide significant parameter bounds for models defining the mode of mantle convection.

  1. Revealing the Earth’s mantle from the tallest mountains using the Jinping Neutrino Experiment

    PubMed Central

    Šrámek, Ondřej; Roskovec, Bedřich; Wipperfurth, Scott A.; Xi, Yufei; McDonough, William F.

    2016-01-01

    The Earth’s engine is driven by unknown proportions of primordial energy and heat produced in radioactive decay. Unfortunately, competing models of Earth’s composition reveal an order of magnitude uncertainty in the amount of radiogenic power driving mantle dynamics. Recent measurements of the Earth’s flux of geoneutrinos, electron antineutrinos from terrestrial natural radioactivity, reveal the amount of uranium and thorium in the Earth and set limits on the residual proportion of primordial energy. Comparison of the flux measured at large underground neutrino experiments with geologically informed predictions of geoneutrino emission from the crust provide the critical test needed to define the mantle’s radiogenic power. Measurement at an oceanic location, distant from nuclear reactors and continental crust, would best reveal the mantle flux, however, no such experiment is anticipated. We predict the geoneutrino flux at the site of the Jinping Neutrino Experiment (Sichuan, China). Within 8 years, the combination of existing data and measurements from soon to come experiments, including Jinping, will exclude end-member models at the 1σ level, define the mantle’s radiogenic contribution to the surface heat loss, set limits on the composition of the silicate Earth, and provide significant parameter bounds for models defining the mode of mantle convection. PMID:27611737

  2. Leaf-scale experiments reveal an important omission in the Penman-Monteith equation

    NASA Astrophysics Data System (ADS)

    Schymanski, Stanislaus J.; Or, Dani

    2017-02-01

    The Penman-Monteith (PM) equation is commonly considered the most advanced physically based approach to computing transpiration rates from plants considering stomatal conductance and atmospheric drivers. It has been widely evaluated at the canopy scale, where aerodynamic and canopy resistance to water vapour are difficult to estimate directly, leading to various empirical corrections when scaling from leaf to canopy. Here, we evaluated the PM equation directly at the leaf scale, using a detailed leaf energy balance model and direct measurements in a controlled, insulated wind tunnel using artificial leaves with fixed and predefined stomatal conductance. Experimental results were consistent with a detailed leaf energy balance model; however, the results revealed systematic deviations from PM-predicted fluxes, which pointed to fundamental problems with the PM equation. Detailed analysis of the derivation by Monteith(1965) and subsequent amendments revealed two errors: one in neglecting two-sided exchange of sensible heat by a planar leaf, and the other related to the representation of hypostomatous leaves, which are very common in temperate climates. The omission of two-sided sensible heat flux led to bias in simulated latent heat flux by the PM equation, which was as high as 50 % of the observed flux in some experiments. Furthermore, we found that the neglect of feedbacks between leaf temperature and radiative energy exchange can lead to additional bias in both latent and sensible heat fluxes. A corrected set of analytical solutions for leaf temperature as well as latent and sensible heat flux is presented, and comparison with the original PM equation indicates a major improvement in reproducing experimental results at the leaf scale. The errors in the original PM equation and its failure to reproduce experimental results at the leaf scale (for which it was originally derived) propagate into inaccurate sensitivities of transpiration and sensible heat fluxes to

  3. Loophole-free Bell test using electron spins in diamond: second experiment and additional analysis

    PubMed Central

    Hensen, B.; Kalb, N.; Blok, M. S.; Dréau, A. E.; Reiserer, A.; Vermeulen, R. F. L.; Schouten, R. N.; Markham, M.; Twitchen, D. J.; Goodenough, K.; Elkouss, D.; Wehner, S.; Taminiau, T. H.; Hanson, R.

    2016-01-01

    The recently reported violation of a Bell inequality using entangled electronic spins in diamonds (Hensen et al., Nature 526, 682–686) provided the first loophole-free evidence against local-realist theories of nature. Here we report on data from a second Bell experiment using the same experimental setup with minor modifications. We find a violation of the CHSH-Bell inequality of 2.35 ± 0.18, in agreement with the first run, yielding an overall value of S = 2.38 ± 0.14. We calculate the resulting P-values of the second experiment and of the combined Bell tests. We provide an additional analysis of the distribution of settings choices recorded during the two tests, finding that the observed distributions are consistent with uniform settings for both tests. Finally, we analytically study the effect of particular models of random number generator (RNG) imperfection on our hypothesis test. We find that the winning probability per trial in the CHSH game can be bounded knowing only the mean of the RNG bias. This implies that our experimental result is robust for any model underlying the estimated average RNG bias, for random bits produced up to 690 ns too early by the random number generator. PMID:27509823

  4. Loophole-free Bell test using electron spins in diamond: second experiment and additional analysis

    NASA Astrophysics Data System (ADS)

    Hensen, B.; Kalb, N.; Blok, M. S.; Dréau, A. E.; Reiserer, A.; Vermeulen, R. F. L.; Schouten, R. N.; Markham, M.; Twitchen, D. J.; Goodenough, K.; Elkouss, D.; Wehner, S.; Taminiau, T. H.; Hanson, R.

    2016-08-01

    The recently reported violation of a Bell inequality using entangled electronic spins in diamonds (Hensen et al., Nature 526, 682–686) provided the first loophole-free evidence against local-realist theories of nature. Here we report on data from a second Bell experiment using the same experimental setup with minor modifications. We find a violation of the CHSH-Bell inequality of 2.35 ± 0.18, in agreement with the first run, yielding an overall value of S = 2.38 ± 0.14. We calculate the resulting P-values of the second experiment and of the combined Bell tests. We provide an additional analysis of the distribution of settings choices recorded during the two tests, finding that the observed distributions are consistent with uniform settings for both tests. Finally, we analytically study the effect of particular models of random number generator (RNG) imperfection on our hypothesis test. We find that the winning probability per trial in the CHSH game can be bounded knowing only the mean of the RNG bias. This implies that our experimental result is robust for any model underlying the estimated average RNG bias, for random bits produced up to 690 ns too early by the random number generator.

  5. The additive effect on suicidality of family history of suicidal behavior and early traumatic experiences.

    PubMed

    Lopez-Castroman, J; Guillaume, S; Olié, E; Jaussent, I; Baca-García, E; Courtet, P

    2015-01-01

    Family history of suicidal behavior and personal history of childhood abuse are reported risk factors for suicide attempts and suicide completion. We aim to quantify the additive effect of family history of suicidal behavior and different subtypes of childhood abuse on suicidal behavior. We examined a sample of 496 suicide attempters, comparing individuals with family history of suicidal behavior and personal history of childhood (physical or sexual) abuse, individuals with family history of suicidal behavior only, individuals with history of early traumatic experiences only, and individuals with none of these two risk factors with regards to suicidal features. An additive effect was found for the age at the first attempt in suicide attempters with both family history of suicidal behavior and either physical or sexual abuse. No significant interactions were found between family history of suicidal behavior and childhood trauma in relation to any characteristics of suicidal behavior. Subjects presenting family history of suicidal behavior and childhood abuse attempt suicide earlier in life than subjects with just one or none of them, particularly if they were sexually abused. Other suicidality indexes were only partially or not associated with this combination of risk factors. A careful assessment of patients with both family history of suicidal behavior and childhood abuse could help to prevent future suicide attempts, particularly in young people.

  6. Genome-wide meta-analysis of maize heterosis reveals the potential role of additive gene expression at pericentromeric loci

    PubMed Central

    2014-01-01

    Background The identification of QTL involved in heterosis formation is one approach to unravel the not yet fully understood genetic basis of heterosis - the improved agronomic performance of hybrid F1 plants compared to their inbred parents. The identification of candidate genes underlying a QTL is important both for developing markers and determining the molecular genetic basis of a trait, but remains difficult owing to the large number of genes often contained within individual QTL. To address this problem in heterosis analysis, we applied a meta-analysis strategy for grain yield (GY) of Zea mays L. as example, incorporating QTL-, hybrid field-, and parental gene expression data. Results For the identification of genes underlying known heterotic QTL, we made use of tight associations between gene expression pattern and the trait of interest, identified by correlation analyses. Using this approach genes strongly associated with heterosis for GY were discovered to be clustered in pericentromeric regions of the complex maize genome. This suggests that expression differences of sequences in recombination-suppressed regions are important in the establishment of heterosis for GY in F1 hybrids and also in the conservation of heterosis for GY across genotypes. Importantly functional analysis of heterosis-associated genes from these genomic regions revealed over-representation of a number of functional classes, identifying key processes contributing to heterosis for GY. Based on the finding that the majority of the analyzed heterosis-associated genes were addtitively expressed, we propose a model referring to the influence of cis-regulatory variation on heterosis for GY by the compensation of fixed detrimental expression levels in parents. Conclusions The study highlights the utility of a meta-analysis approach that integrates phenotypic and multi-level molecular data to unravel complex traits in plants. It provides prospects for the identification of genes relevant for

  7. Single-Amino Acid Modifications Reveal Additional Controls on the Proton Pathway of [FeFe]-Hydrogenase

    SciTech Connect

    Cornish, Adam J.; Ginovska, Bojana; Thelen, Adam; da Silva, Julio C. S.; Soares, Thereza A.; Raugei, Simone; Dupuis, Michel; Shaw, Wendy J.; Hegg, Eric L.

    2016-06-07

    The proton pathway of [FeFe]-hydrogenase is essential for enzymatic H2 production and oxidation and is composed of four residues and a modeled water molecule. Recently, a computational analysis of this pathway revealed that the solvent-exposed residue of the pathway (Glu282) could form hydrogen bonds to two residues outside of the pathway (Arg286 and Ser320), implicating that these residues could function in regulating proton transfer. Substituting Arg286 with leucine eliminates hydrogen bonding with Glu282 and results in a 2.5-fold enhancement in H2 production activity, suggesting that Arg286 serves an important role in controlling the rate of proton delivery. In contrast, substitution of Ser320 with alanine reduces the rate approximately 5-fold, implying that it either acts as a member of the pathway or influences Glu282 to enable proton transfer. Interestingly, QM/MM and molecular dynamics calculations indicate that Ser320 does not play an electronic or structural role. QM calculations also estimate that including Ser320 in the pathway does not significantly change the barrier to proton movement, providing further support for its role as a member of the proton pathway. While further studies are needed to quantify the role of Ser320, collectively, these data provide evidence that the enzyme scaffold plays a significant role in modulating the activity of the enzyme, demonstrating that the rate of intraprotein proton transfer can be accelerated, particularly in a non-biological context. This work was supported by the DOE Great Lakes Bioenergy Research Center (DOE BER Office of Science, DE-FC02-07ER64494). In addition, support from the DOE Office of Science Early Career Research Program through the Office of Basic Energy Sciences (WJS, BGP, SR) is gratefully acknowledged. Computational resources were provided at W. R. Wiley Environmental Molecular Science Laboratory (EMSL), a national scientific user facility sponsored by the Department of Energy’s Office of

  8. Additions and Improvements to the FLASH Code for Simulating High Energy Density Physics Experiments

    NASA Astrophysics Data System (ADS)

    Lamb, D. Q.; Daley, C.; Dubey, A.; Fatenejad, M.; Flocke, N.; Graziani, C.; Lee, D.; Tzeferacos, P.; Weide, K.

    2015-11-01

    FLASH is an open source, finite-volume Eulerian, spatially adaptive radiation hydrodynamics and magnetohydrodynamics code that incorporates capabilities for a broad range of physical processes, performs well on a wide range of computer architectures, and has a broad user base. Extensive capabilities have been added to FLASH to make it an open toolset for the academic high energy density physics (HEDP) community. We summarize these capabilities, with particular emphasis on recent additions and improvements. These include advancements in the optical ray tracing laser package, with methods such as bi-cubic 2D and tri-cubic 3D interpolation of electron number density, adaptive stepping and 2nd-, 3rd-, and 4th-order Runge-Kutta integration methods. Moreover, we showcase the simulated magnetic field diagnostic capabilities of the code, including induction coils, Faraday rotation, and proton radiography. We also describe several collaborations with the National Laboratories and the academic community in which FLASH has been used to simulate HEDP experiments. This work was supported in part at the University of Chicago by the DOE NNSA ASC through the Argonne Institute for Computing in Science under field work proposal 57789; and the NSF under grant PHY-0903997.

  9. An experiment in software reliability: Additional analyses using data from automated replications

    NASA Technical Reports Server (NTRS)

    Dunham, Janet R.; Lauterbach, Linda A.

    1988-01-01

    A study undertaken to collect software error data of laboratory quality for use in the development of credible methods for predicting the reliability of software used in life-critical applications is summarized. The software error data reported were acquired through automated repetitive run testing of three independent implementations of a launch interceptor condition module of a radar tracking problem. The results are based on 100 test applications to accumulate a sufficient sample size for error rate estimation. The data collected is used to confirm the results of two Boeing studies reported in NASA-CR-165836 Software Reliability: Repetitive Run Experimentation and Modeling, and NASA-CR-172378 Software Reliability: Additional Investigations into Modeling With Replicated Experiments, respectively. That is, the results confirm the log-linear pattern of software error rates and reject the hypothesis of equal error rates per individual fault. This rejection casts doubt on the assumption that the program's failure rate is a constant multiple of the number of residual bugs; an assumption which underlies some of the current models of software reliability. data raises new questions concerning the phenomenon of interacting faults.

  10. Additive Manufacturing, Design, Testing, and Fabrication: A Full Engineering Experience at JSC

    NASA Technical Reports Server (NTRS)

    Zusack, Steven

    2016-01-01

    I worked on several projects this term. While most projects involved additive manufacturing, I was also involved with two design projects, two testing projects, and a fabrication project. The primary mentor for these was Richard Hagen. Secondary mentors were Hai Nguyen, Khadijah Shariff, and fabrication training from James Brown. Overall, my experience at JSC has been successful and what I have learned will continue to help me in my engineering education and profession long after I leave. My 3D printing projects ranged from less than a 1 cubic centimeter to about 1 cubic foot and involved several printers using different printing technologies. It was exciting to become familiar with printing technologies such as industrial grade FDM (Fused Deposition Modeling), the relatively new SLA (Stereolithography), and PolyJet. My primary duty with the FDM printers was to model parts that came in from various sources to print effectively and efficiently. Using methods my mentor taught me and the Stratasys Insight software, I was able to minimize imperfections, hasten build time, improve strength for specific forces (tensile, shear, etc...), and reduce likelihood of a print-failure. Also using FDM, I learned how to repair a part after it was printed. This is done by using a special kind of glue that chemically melts the two faces of plastic parts together to form a fused interface. My first goal with SLA technology was to bring the printer back to operational readiness. In becoming familiar with the Pegasus SLA printer, I researched the leveling, laser settings, and different vats to hold liquid material. With this research, I was successfully able to bring the Pegasus back online and have successfully printed multiple sample parts as well as functional parts. My experience with PolyJet technology has been focused on an understanding of the abilities/limits, costs, and the maintenance for daily use. Still upcoming will be experience with using a composite printer that uses FDM

  11. Understanding Biases in Ribosome Profiling Experiments Reveals Signatures of Translation Dynamics in Yeast

    PubMed Central

    Hussmann, Jeffrey A.; Patchett, Stephanie; Johnson, Arlen; Sawyer, Sara; Press, William H.

    2015-01-01

    Ribosome profiling produces snapshots of the locations of actively translating ribosomes on messenger RNAs. These snapshots can be used to make inferences about translation dynamics. Recent ribosome profiling studies in yeast, however, have reached contradictory conclusions regarding the average translation rate of each codon. Some experiments have used cycloheximide (CHX) to stabilize ribosomes before measuring their positions, and these studies all counterintuitively report a weak negative correlation between the translation rate of a codon and the abundance of its cognate tRNA. In contrast, some experiments performed without CHX report strong positive correlations. To explain this contradiction, we identify unexpected patterns in ribosome density downstream of each type of codon in experiments that use CHX. These patterns are evidence that elongation continues to occur in the presence of CHX but with dramatically altered codon-specific elongation rates. The measured positions of ribosomes in these experiments therefore do not reflect the amounts of time ribosomes spend at each position in vivo. These results suggest that conclusions from experiments in yeast using CHX may need reexamination. In particular, we show that in all such experiments, codons decoded by less abundant tRNAs were in fact being translated more slowly before the addition of CHX disrupted these dynamics. PMID:26656907

  12. Understanding Biases in Ribosome Profiling Experiments Reveals Signatures of Translation Dynamics in Yeast.

    PubMed

    Hussmann, Jeffrey A; Patchett, Stephanie; Johnson, Arlen; Sawyer, Sara; Press, William H

    2015-12-01

    Ribosome profiling produces snapshots of the locations of actively translating ribosomes on messenger RNAs. These snapshots can be used to make inferences about translation dynamics. Recent ribosome profiling studies in yeast, however, have reached contradictory conclusions regarding the average translation rate of each codon. Some experiments have used cycloheximide (CHX) to stabilize ribosomes before measuring their positions, and these studies all counterintuitively report a weak negative correlation between the translation rate of a codon and the abundance of its cognate tRNA. In contrast, some experiments performed without CHX report strong positive correlations. To explain this contradiction, we identify unexpected patterns in ribosome density downstream of each type of codon in experiments that use CHX. These patterns are evidence that elongation continues to occur in the presence of CHX but with dramatically altered codon-specific elongation rates. The measured positions of ribosomes in these experiments therefore do not reflect the amounts of time ribosomes spend at each position in vivo. These results suggest that conclusions from experiments in yeast using CHX may need reexamination. In particular, we show that in all such experiments, codons decoded by less abundant tRNAs were in fact being translated more slowly before the addition of CHX disrupted these dynamics.

  13. Automated microbial metabolism laboratory. [design of advanced labeled release experiment based on single addition of soil and multiple sequential additions of media into test chambers

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The design and rationale of an advanced labeled release experiment based on single addition of soil and multiple sequential additions of media into each of four test chambers are outlined. The feasibility for multiple addition tests was established and various details of the methodology were studied. The four chamber battery of tests include: (1) determination of the effect of various atmospheric gases and selection of that gas which produces an optimum response; (2) determination of the effect of incubation temperature and selection of the optimum temperature for performing Martian biochemical tests; (3) sterile soil is dosed with a battery of C-14 labeled substrates and subjected to experimental temperature range; and (4) determination of the possible inhibitory effects of water on Martian organisms is performed initially by dosing with 0.01 ml and 0.5 ml of medium, respectively. A series of specifically labeled substrates are then added to obtain patterns in metabolic 14CO2 (C-14)O2 evolution.

  14. Police arrest and self-defence skills: performance under anxiety of officers with and without additional experience in martial arts.

    PubMed

    Renden, Peter G; Landman, Annemarie; Savelsbergh, Geert J P; Oudejans, Raôul R D

    2015-01-01

    We investigated whether officers with additional martial arts training experience performed better in arrest and self-defence scenarios under low and high anxiety and were better able to maintain performance under high anxiety than officers who just rely on regular police training. We were especially interested to find out whether training once a week would already lead to better performance under high anxiety. Officers with additional experience in kickboxing or karate/jiu-jitsu (training several times per week), or krav maga (training once a week) and officers with no additional experience performed several arrest and self-defence skills under low and high anxiety. Results showed that officers with additional experience (also those who trained once a week) performed better under high anxiety than officers with no additional experience. Still, the additional experience did not prevent these participants from performing worse under high anxiety compared to low anxiety. Implications for training are discussed. Practitioner summary: Dutch police officers train their arrest and self-defence skills only four to six hours per year. Our results indicate that doing an additional martial arts training once a week may lead to better performance under anxiety, although it cannot prevent that performance decreases under high anxiety compared to low anxiety.

  15. Nitrate removal in stream ecosystems measured by 15N addition experiments: Total uptake

    SciTech Connect

    Mulholland, Patrick J; Hall, Robert; Tank, Jennifer; Sobota, Daniel; O'Brien, Jon; Webster, Jackson; Valett, H. Maurice; Dodds, Walter; Poole, Geoff; Peterson, Chris G.; Meyer, Judy; McDowell, William; Johnson, Sherri; Hamilton, Stephen; Gregory, Stanley; Grimm, Nancy; Dahm, Cliff; Cooper, Lee W; Ashkenas, Linda; Thomas, Suzanne; Sheibley, Rich; Potter, Jody; Niederlehner, Bobbie; Johnson, Laura; Helton, Ashley; Crenshaw, Chelsea; Burgin, Amy; Bernot, Melody; Beaulieu, Jake; Arango, Clay

    2009-01-01

    We measured uptake length of {sup 15}NO{sub 3}{sup -} in 72 streams in eight regions across the United States and Puerto Rico to develop quantitative predictive models on controls of NO{sub 3}{sup -} uptake length. As part of the Lotic Intersite Nitrogen Experiment II project, we chose nine streams in each region corresponding to natural (reference), suburban-urban, and agricultural land uses. Study streams spanned a range of human land use to maximize variation in NO{sub 3}{sup -} concentration, geomorphology, and metabolism. We tested a causal model predicting controls on NO{sub 3}{sup -} uptake length using structural equation modeling. The model included concomitant measurements of ecosystem metabolism, hydraulic parameters, and nitrogen concentration. We compared this structural equation model to multiple regression models which included additional biotic, catchment, and riparian variables. The structural equation model explained 79% of the variation in log uptake length (S{sub Wtot}). Uptake length increased with specific discharge (Q/w) and increasing NO{sub 3}{sup -} concentrations, showing a loss in removal efficiency in streams with high NO{sub 3}{sup -} concentration. Uptake lengths shortened with increasing gross primary production, suggesting autotrophic assimilation dominated NO{sub 3}{sup -} removal. The fraction of catchment area as agriculture and suburban-urban land use weakly predicted NO{sub 3}{sup -} uptake in bivariate regression, and did improve prediction in a set of multiple regression models. Adding land use to the structural equation model showed that land use indirectly affected NO{sub 3}{sup -} uptake lengths via directly increasing both gross primary production and NO{sub 3}{sup -} concentration. Gross primary production shortened S{sub Wtot}, while increasing NO{sub 3}{sup -} lengthened S{sub Wtot} resulting in no net effect of land use on NO{sub 3}{sup -} removal.

  16. Nitrate removal in stream ecosystems measured by 15N addition experiments: Total uptake

    USGS Publications Warehouse

    Hall, R.O.; Tank, J.L.; Sobota, D.J.; Mulholland, P.J.; O'Brien, J. M.; Dodds, W.K.; Webster, J.R.; Valett, H.M.; Poole, G.C.; Peterson, B.J.; Meyer, J.L.; McDowell, W.H.; Johnson, S.L.; Hamilton, S.K.; Grimm, N. B.; Gregory, S.V.; Dahm, Clifford N.; Cooper, L.W.; Ashkenas, L.R.; Thomas, S.M.; Sheibley, R.W.; Potter, J.D.; Niederlehner, B.R.; Johnson, L.T.; Helton, A.M.; Crenshaw, C.M.; Burgin, A.J.; Bernot, M.J.; Beaulieu, J.J.; Arangob, C.P.

    2009-01-01

    We measured uptake length of 15NO-3 in 72 streams in eight regions across the United States and Puerto Rico to develop quantitative predictive models on controls of NO-3 uptake length. As part of the Lotic Intersite Nitrogen eXperiment II project, we chose nine streams in each region corresponding to natural (reference), suburban-urban, and agricultural land uses. Study streams spanned a range of human land use to maximize variation in NO-3 concentration, geomorphology, and metabolism. We tested a causal model predicting controls on NO-3 uptake length using structural equation modeling. The model included concomitant measurements of ecosystem metabolism, hydraulic parameters, and nitrogen concentration. We compared this structural equation model to multiple regression models which included additional biotic, catchment, and riparian variables. The structural equation model explained 79% of the variation in log uptake length (S Wtot). Uptake length increased with specific discharge (Q/w) and increasing NO-3 concentrations, showing a loss in removal efficiency in streams with high NO-3 concentration. Uptake lengths shortened with increasing gross primary production, suggesting autotrophic assimilation dominated NO-3 removal. The fraction of catchment area as agriculture and suburban-urban land use weakly predicted NO-3 uptake in bivariate regression, and did improve prediction in a set of multiple regression models. Adding land use to the structural equation model showed that land use indirectly affected NO-3 uptake lengths via directly increasing both gross primary production and NO-3 concentration. Gross primary production shortened SWtot, while increasing NO-3 lengthened SWtot resulting in no net effect of land use on NO- 3 removal. ?? 2009.

  17. Shades of Emotion: What the Addition of Sunglasses or Masks to Faces Reveals about the Development of Facial Expression Processing

    ERIC Educational Resources Information Center

    Roberson, Debi; Kikutani, Mariko; Doge, Paula; Whitaker, Lydia; Majid, Asifa

    2012-01-01

    Three studies investigated developmental changes in facial expression processing, between 3 years-of-age and adulthood. For adults and older children, the addition of sunglasses to upright faces caused an equivalent decrement in performance to face inversion. However, younger children showed "better" classification of expressions of faces wearing…

  18. Photoinduced Oxidative DNA Damage Revealed by an Agarose Gel Nicking Assay: A Biophysical Chemistry Laboratory Experiment

    NASA Astrophysics Data System (ADS)

    Shafirovich, Vladimir; Singh, Carolyn; Geacintov, Nicholas E.

    2003-11-01

    Oxidative damage of DNA molecules associated with electron-transfer reactions is an important phenomenon in living cells, which can lead to mutations and contribute to carcinogenesis and the aging processes. This article describes the design of several simple experiments to explore DNA damage initiated by photoinduced electron-transfer reactions sensitized by the acridine derivative, proflavine (PF). A supercoiled DNA agarose gel nicking assay is employed as a sensitive probe of DNA strand cleavage. A low-cost experimental and computer-interfaced imaging apparatus is described allowing for the digital recording and analysis of the gel electrophoresis results. The first experiment describes the formation of direct strand breaks in double-stranded DNA induced by photoexcitation of the intercalated PF molecules. The second experiment demonstrates that the addition of the well-known electron acceptor, methylviologen, gives rise to a significant enhancement of the photochemical DNA strand cleavage effect. This occurs by an electron transfer step to methylviologen that renders the inital photoinduced charge separation between photoexcited PF and DNA irreversible. The third experiment demonstrates that the action spectrum of the DNA photocleavage matches the absorption spectrum of DNA-bound, intercalated PF molecules, which differs from that of free PF molecules. This result demonstrates that the photoinduced DNA strand cleavage is initiated by intercalated rather than free PF molecules.

  19. Non-additive genome-wide association scan reveals a new gene associated with habitual coffee consumption

    PubMed Central

    Pirastu, Nicola; Kooyman, Maarten; Robino, Antonietta; van der Spek, Ashley; Navarini, Luciano; Amin, Najaf; Karssen, Lennart C.; Van Duijn, Cornelia M; Gasparini, Paolo

    2016-01-01

    Coffee is one of the most consumed beverages world-wide and one of the primary sources of caffeine intake. Given its important health and economic impact, the underlying genetics of its consumption has been widely studied. Despite these efforts, much has still to be uncovered. In particular, the use of non-additive genetic models may uncover new information about the genetic variants driving coffee consumption. We have conducted a genome-wide association study in two Italian populations using additive, recessive and dominant models for analysis. This has uncovered a significant association in the PDSS2 gene under the recessive model that has been replicated in an independent cohort from the Netherlands (ERF). The identified gene has been shown to negatively regulate the expression of the caffeine metabolism genes and can thus be linked to coffee consumption. Further bioinformatics analysis of eQTL and histone marks from Roadmap data has evidenced a possible role of the identified SNPs in regulating PDSS2 gene expression through enhancers present in its intron. Our results highlight a novel gene which regulates coffee consumption by regulating the expression of the genes linked to caffeine metabolism. Further studies will be needed to clarify the biological mechanism which links PDSS2 and coffee consumption. PMID:27561104

  20. LUT REVEALS AN ALGOL-TYPE ECLIPSING BINARY WITH THREE ADDITIONAL STELLAR COMPANIONS IN A MULTIPLE SYSTEM

    SciTech Connect

    Zhu, L.-Y.; Zhou, X.; Qian, S.-B.; Li, L.-J.; Liao, W.-P.; Tian, X.-M.; Wang, Z.-H.; Hu, J.-Y.

    2016-04-15

    A complete light curve of the neglected eclipsing binary Algol V548 Cygni in the UV band was obtained with the Lunar-based Ultraviolet Telescope in 2014 May. Photometric solutions are obtained using the Wilson–Devinney method. It is found that solutions with and without third light are quite different. The mass ratio without third light is determined to be q = 0.307, while that derived with third light is q = 0.606. It is shown that V548 Cygni is a semi-detached binary where the secondary component is filling the critical Roche lobe. An analysis of all available eclipse times suggests that there are three cyclic variations in the O–C diagram that are interpreted by the light travel-time effect via the presence of three additional stellar companions. This is in agreement with the presence of a large quantity of third light in the system. The masses of these companions are estimated as m sin i′ ∼ 1.09, 0.20, and 0.52 M{sub ⊙}. They are orbiting the central binary with orbital periods of about 5.5, 23.3, and 69.9 years, i.e., in 1:4:12 resonance orbit. Their orbital separations are about 4.5, 13.2, and 26.4 au, respectively. Our photometric solutions suggest that they contribute about 32.4% to the total light of the multiple system. No obvious long-term changes in the orbital period were found, indicating that the contributions of the mass transfer and the mass loss due to magnetic braking to the period variations are comparable. The detection of three possible additional stellar components orbiting a typical Algol in a multiple system make V548 Cygni a very interesting binary to study in the future.

  1. LUT Reveals an Algol-type Eclipsing Binary With Three Additional Stellar Companions in a Multiple System

    NASA Astrophysics Data System (ADS)

    Zhu, L.-Y.; Zhou, X.; Hu, J.-Y.; Qian, S.-B.; Li, L.-J.; Liao, W.-P.; Tian, X.-M.; Wang, Z.-H.

    2016-04-01

    A complete light curve of the neglected eclipsing binary Algol V548 Cygni in the UV band was obtained with the Lunar-based Ultraviolet Telescope in 2014 May. Photometric solutions are obtained using the Wilson-Devinney method. It is found that solutions with and without third light are quite different. The mass ratio without third light is determined to be q = 0.307, while that derived with third light is q = 0.606. It is shown that V548 Cygni is a semi-detached binary where the secondary component is filling the critical Roche lobe. An analysis of all available eclipse times suggests that there are three cyclic variations in the O-C diagram that are interpreted by the light travel-time effect via the presence of three additional stellar companions. This is in agreement with the presence of a large quantity of third light in the system. The masses of these companions are estimated as m sin i‧ ˜ 1.09, 0.20, and 0.52 M⊙. They are orbiting the central binary with orbital periods of about 5.5, 23.3, and 69.9 years, i.e., in 1:4:12 resonance orbit. Their orbital separations are about 4.5, 13.2, and 26.4 au, respectively. Our photometric solutions suggest that they contribute about 32.4% to the total light of the multiple system. No obvious long-term changes in the orbital period were found, indicating that the contributions of the mass transfer and the mass loss due to magnetic braking to the period variations are comparable. The detection of three possible additional stellar components orbiting a typical Algol in a multiple system make V548 Cygni a very interesting binary to study in the future.

  2. The effect of tailor-made additives on crystal growth of methyl paraben: Experiments and modelling

    NASA Astrophysics Data System (ADS)

    Cai, Zhihui; Liu, Yong; Song, Yang; Guan, Guoqiang; Jiang, Yanbin

    2017-03-01

    In this study, methyl paraben (MP) was selected as the model component, and acetaminophen (APAP), p-methyl acetanilide (PMAA) and acetanilide (ACET), which share the similar molecular structure as MP, were selected as the three tailor-made additives to study the effect of tailor-made additives on the crystal growth of MP. HPLC results indicated that the MP crystals induced by the three additives contained MP only. Photographs of the single crystals prepared indicated that the morphology of the MP crystals was greatly changed by the additives, but PXRD and single crystal diffraction results illustrated that the MP crystals were the same polymorph only with different crystal habits, and no new crystal form was found compared with other references. To investigate the effect of the additives on the crystal growth, the interaction between additives and facets was discussed in detail using the DFT methods and MD simulations. The results showed that APAP, PMAA and ACET would be selectively adsorbed on the growth surfaces of the crystal facets, which induced the change in MP crystal habits.

  3. Revealing moments: formulating understandings of adverse experiences in a health appraisal interview.

    PubMed

    Beach, W A; Dixson, C N

    2001-01-01

    Analysis of a health appraisal interview reveals how an interviewer employs formulations to organize talk about a patient's medical history. When selected reportings by patient are paraphrased, a three-part formulations cycle is initiated: (1) interviewer's formulated understandings, (2) patient's confirmation, and (3) topic shift by interviewer. The reenactment of this interactional pattern promotes increasing attention to patient's adverse experiences as "root problems" underlying adult health status (e.g. molestation, obesity, depression). Creating an environment for patient's emergent disclosures is facilitated by displaying non-judgmental sensitivity to patient's stated concerns, soliciting alignment to particular reconstructions and avoidance of moving the interview forward prematurely and to issues not grounded in patient's illness circumstances. The identification and utilization of communication techniques for attending to patient's bio-psycho-social history is critical for refining understandings of empathic interviewing, enhancing diagnosis and treatment (e.g. referrals), decreasing patients' utilization of health care systems, and ultimately reducing costs for quality medical care.

  4. Revealing the Effect of Additives with Different Solubility on the Morphology and the Donor Crystalline Structures of Organic Solar Cells.

    PubMed

    Zhao, Jiao; Zhao, Suling; Xu, Zheng; Qiao, Bo; Huang, Di; Zhao, Ling; Li, Yang; Zhu, Youqin; Wang, Peng

    2016-07-20

    The impact of two kinds of additives, such as 1,8-octanedithiol (ODT), 1,8-diiodooctane (DIO), diphenylether (DPE), and 1-chloronaphthalene (CN), on the performance of poly[(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3‴-di(2-octyldodecyl)2,2';5',2″;5″,2‴-quaterthiophen-5,5‴-diyl)] (PffBT4T-2OD):[6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) based polymer solar cell are investigated. The polymer solar cells (PSCs) of PffBT4T-2OD:PC71BM by using CN show a more improved PCE of 10.23%. The solubility difference of PffBT4T-2OD in DIO and CN creates the fine transformation in phase separation and favorable nanoscale morphology. Grazing incidence X-ray diffraction (GIXRD) data clearly shows molecular stacking and orientation of the active layer. Interestingly, DIO and CN have different functions on the effect of the molecular orientation. These interesting studies provide important guidance to optimize and control complicated molecular orientations and nanoscale morphology of PffBT4T-2OD based thick films for the application in PSCs.

  5. Hyperbaric oxygen therapy as additional treatment in deep sternal wound infections – a single center's experience

    PubMed Central

    Bryndza, Magdalena; Chrapusta, Anna; Kobielska, Ewa; Kapelak, Bogusław; Grudzień, Grzegorz

    2016-01-01

    Introduction Deep sternal wound infection (DSWI) is one of the most serious complications after cardiac surgery procedures, observed in 5% of patients. Current standard medical therapy for DSWI includes antibiotics, surgical debridement, resuturing or negative pressure wound therapy (NPWT). Unfortunately, in some cases these methods are insufficient, and additional therapeutic options are needed. Aim To assess the effects and usefulness of additional hyperbaric oxygen therapy (HBO2) in patients with DSWI after cardiac surgery procedures. Material and methods A retrospective analysis of 10 patients after cardiac surgery who developed DSWI in the period 2010–2012 was performed. After 3 months of ineffective conventional therapy including targeted antibiotic, surgical sternal debridement and NPWT, patients were qualified for additional HBO2 therapy. A total of 20 sessions of HBO2 therapy were performed, each 92 minutes long. Results After 4 weeks of HBO2 treatment, 7 patients presented complete wound healing with fibrous scar formation. One patient was qualified for the another cycle of HBO2 therapy with 20 additional sessions, and complete wound healing was observed. In 2 cases, after 5 and 19 sessions, HBO2 was interrupted because of improper qualifications. Conclusions The HBO2 as an additional therapy in DSWI was successful in 80% of cases, and no complications were observed. However, due to the small number of published studies with a small number of patients, randomized, clinical trials are needed to assess the clinical results of HBO2 in DSWI after cardiac surgery procedures. PMID:27785131

  6. Exposure and Experience: Additional Criteria for Selecting Future Operational Theater Commanders

    DTIC Science & Technology

    2009-10-23

    Kaufmann. From Plato to Derrida . Upper Saddle River, New Jersey: Pearson Prentice Hall, 2008. 8 Experience Comparison of Former...Forrest E., and Walter Kaufmann. From Plato to Derrida . Upper Saddle River, New Jersey: Pearson Prentice Hall, 2008. Bell, William Gardner. Center

  7. Unaware yet reliant on attention: Experience sampling reveals that mind-wandering impedes implicit learning.

    PubMed

    Franklin, Michael S; Smallwood, Jonathan; Zedelius, Claire M; Broadway, James M; Schooler, Jonathan W

    2016-02-01

    Although implicit learning has been widely studied, controversy remains regarding its reliance on attentional resources. A central issue in this controversy is the question of how best to manipulate attention. The usual approach of comparing implicit learning in a serial reaction time (SRT) task under single- versus dual-task conditions is known to be problematic, because the secondary task may not only divert attention away from the primary task, but also interfere with the implicit-learning process itself. To address this confound, in the present study we used an experience-sampling instead of a dual-task approach. We assessed lapses of attention (mind-wandering) with experience-sampling thought probes during a standard implicit-learning SRT task. The results revealed a significant negative correlation between mind-wandering and implicit learning. Thus, greater task focus was associated with improved implicit sequence learning. This result suggests that, at least in the context of this SRT task, optimal implicit learning relies on attention.

  8. National hiring experiments reveal 2:1 faculty preference for women on STEM tenure track.

    PubMed

    Williams, Wendy M; Ceci, Stephen J

    2015-04-28

    National randomized experiments and validation studies were conducted on 873 tenure-track faculty (439 male, 434 female) from biology, engineering, economics, and psychology at 371 universities/colleges from 50 US states and the District of Columbia. In the main experiment, 363 faculty members evaluated narrative summaries describing hypothetical female and male applicants for tenure-track assistant professorships who shared the same lifestyle (e.g., single without children, married with children). Applicants' profiles were systematically varied to disguise identically rated scholarship; profiles were counterbalanced by gender across faculty to enable between-faculty comparisons of hiring preferences for identically qualified women versus men. Results revealed a 2:1 preference for women by faculty of both genders across both math-intensive and non-math-intensive fields, with the single exception of male economists, who showed no gender preference. Results were replicated using weighted analyses to control for national sample characteristics. In follow-up experiments, 144 faculty evaluated competing applicants with differing lifestyles (e.g., divorced mother vs. married father), and 204 faculty compared same-gender candidates with children, but differing in whether they took 1-y-parental leaves in graduate school. Women preferred divorced mothers to married fathers; men preferred mothers who took leaves to mothers who did not. In two validation studies, 35 engineering faculty provided rankings using full curricula vitae instead of narratives, and 127 faculty rated one applicant rather than choosing from a mixed-gender group; the same preference for women was shown by faculty of both genders. These results suggest it is a propitious time for women launching careers in academic science. Messages to the contrary may discourage women from applying for STEM (science, technology, engineering, mathematics) tenure-track assistant professorships.

  9. English as an Additional Language (EAL) "viva voce": The EAL Doctoral Oral Examination Experience

    ERIC Educational Resources Information Center

    Carter, Susan

    2012-01-01

    Is the doctoral "viva voce" a reasonable method of examination? This exploratory paper proposes that the doctoral "viva voce" (oral examination) is a slightly different hurdle for doctoral candidates for whom English is an additional language (EAL, also termed ESL) than for those whose first language is English. It investigates…

  10. Designing Location-Based Learning Experiences for People with Intellectual Disabilities and Additional Sensory Impairments

    ERIC Educational Resources Information Center

    Brown, David J.; McHugh, David; Standen, Penny; Evett, Lindsay; Shopland, Nick; Battersby, Steven

    2011-01-01

    The research reported here is part of a larger project which seeks to combine serious games (or games-based learning) with location-based services to help people with intellectual disabilities and additional sensory impairments to develop work based skills. Specifically this paper reports on where these approaches are combined to scaffold the…

  11. Laser Additive Melting and Solidification of Inconel 718: Finite Element Simulation and Experiment

    NASA Astrophysics Data System (ADS)

    Romano, John; Ladani, Leila; Sadowski, Magda

    2016-03-01

    The field of powdered metal additive manufacturing is experiencing a surge in public interest finding uses in aerospace, defense, and biomedical industries. The relative youth of the technology coupled with public interest makes the field a vibrant research topic. The authors have expanded upon previously published finite element models used to analyze the processing of novel engineering materials through the use of laser- and electron beam-based additive manufacturing. In this work, the authors present a model for simulating fabrication of Inconel 718 using laser melting processes. Thermal transport phenomena and melt pool geometries are discussed and validation against experimental findings is presented. After comparing experimental and simulation results, the authors present two correction correlations to transform the modeling results into meaningful predictions of actual laser melting melt pool geometries in Inconel 718.

  12. Additive Manufacture (3D Printing) of Plasma Diagnostic Components and Assemblies for Fusion Experiments

    NASA Astrophysics Data System (ADS)

    Quinley, Morgan; Chun, Katherine; Melnik, Paul; Sieck, Paul; Smith, Trevor; Stuber, James; Woodruff, Simon; Romero-Talamas, Carlos; Rivera, William; Card, Alexander

    2016-10-01

    We are investigating the potential impact of additive manufacturing (3D printing) on the cost and complexity of plasma diagnostics. We present a survey of the current state-of-the-art in additive manufacture of metals, as well as the design of diagnostic components that have been optimized for and take advantage of these processes. Included among these is a set of retarding field analyzer probe heads that have been printed in tungsten with internal heat sinks and cooling channels. Finite element analysis of these probe heads shows the potential for a 750K reduction in peak temperature, allowing the probe to take data twice as often without melting. Results of the evaluation of these probe heads for mechanical strength and outgassing, as well as their use on Alcator C-Mod will be presented. Supported by DOE SBIR Grant DE-SC0011858.

  13. Additional results on space environmental effects on polymer matrix composites: Experiment A0180

    NASA Technical Reports Server (NTRS)

    Tennyson, R. C.

    1992-01-01

    Additional experimental results on the atomic oxygen erosion of boron, Kevlar, and graphite fiber reinforced epoxy matrix composites are presented. Damage of composite laminates due to micrometeoroid/debris impacts is also examined with particular emphasis on the relationship between damage area and actual hole size due to particle penetration. Special attention is given to one micrometeoroid impact on an aluminum base plate which resulted in ejecta visible on an adjoining vertical flange structure.

  14. Experiments to Populate and Validate a Processing Model for Polyurethane Foam: Additional Data for Structural Foams

    SciTech Connect

    Rao, Rekha R.; Celina, Mathias C.; Giron, Nicholas Henry; Long, Kevin Nicholas; Russick, Edward M.

    2015-01-01

    We are developing computational models to help understand manufacturing processes, final properties and aging of structural foam, polyurethane PMDI. Th e resulting model predictions of density and cure gradients from the manufacturing process will be used as input to foam heat transfer and mechanical models. BKC 44306 PMDI-10 and BKC 44307 PMDI-18 are the most prevalent foams used in structural parts. Experiments needed to parameterize models of the reaction kinetics and the equations of motion during the foam blowing stages were described for BKC 44306 PMDI-10 in the first of this report series (Mondy et al. 2014). BKC 44307 PMDI-18 is a new foam that will be used to make relatively dense structural supports via over packing. It uses a different catalyst than those in the BKC 44306 family of foams; hence, we expect that the reaction kineti cs models must be modified. Here we detail the experiments needed to characteriz e the reaction kinetics of BKC 44307 PMDI-18 and suggest parameters for the model based on these experiments. In additi on, the second part of this report describes data taken to provide input to the preliminary nonlinear visco elastic structural response model developed for BKC 44306 PMDI-10 foam. We show that the standard cu re schedule used by KCP does not fully cure the material, and, upon temperature elevation above 150°C, oxidation or decomposition reactions occur that alter the composition of the foam. These findings suggest that achieving a fully cured foam part with this formulation may be not be possible through therma l curing. As such, visco elastic characterization procedures developed for curing thermosets can provide only approximate material properties, since the state of the material continuously evolves during tests.

  15. The ARSQ 2.0 reveals age and personality effects on mind-wandering experiences

    PubMed Central

    Diaz, B. Alexander; Van Der Sluis, Sophie; Benjamins, Jeroen S.; Stoffers, Diederick; Hardstone, Richard; Mansvelder, Huibert D.; Van Someren, Eus J. W.; Linkenkaer-Hansen, Klaus

    2014-01-01

    The human brain frequently generates thoughts and feelings detached from environmental demands. Investigating the rich repertoire of these mind-wandering experiences is challenging, as it depends on introspection and mapping its content requires an unknown number of dimensions. We recently developed a retrospective self-report questionnaire—the Amsterdam Resting-State Questionnaire (ARSQ)—which quantifies mind wandering along seven dimensions: “Discontinuity of Mind,” “Theory of Mind,” “Self,” “Planning,” “Sleepiness,” “Comfort,” and “Somatic Awareness.” Here, we show using confirmatory factor analysis that the ARSQ can be simplified by standardizing the number of items per factor and extending it to a 10-dimensional model, adding “Health Concern,” “Visual Thought,” and “Verbal Thought.” We will refer to this extended ARSQ as the “ARSQ 2.0.” Testing for effects of age and gender revealed no main effect for gender, yet a moderate and significant negative effect for age on the dimensions of “Self,” “Planning,” and “Visual Thought.” Interestingly, we observed stable and significant test-retest correlations across measurement intervals of 3–32 months except for “Sleepiness” and “Health Concern.” To investigate whether this stability could be related to personality traits, we correlated ARSQ scores to proxy measures of Cloninger's Temperament and Character Inventory, revealing multiple significant associations for the trait “Self-Directedness.” Other traits correlated to specific ARSQ dimensions, e.g., a negative association between “Harm Avoidance” and “Comfort.” Together, our results suggest that the ARSQ 2.0 is a promising instrument for quantitative studies on mind wandering and its relation to other psychological or physiological phenomena. PMID:24772097

  16. Experiences of clinical tutors with English as an additional language (EAL) students.

    PubMed

    Lu, Hongyan; Maithus, Caroline

    2012-11-01

    Clinical tutors, referred to in the international literature as clinical supervisors, facilitators, mentors or instructors, are responsible for providing and supervising workplace learning opportunities for groups of Bachelor of Nursing (BN) students. They also play a key role in assessing students. The role modeling and support provided by both clinical tutors and registered nurses (RN) or nurse preceptors helps students become familiar with the language in which nursing work is realised. As BN student cohorts in New Zealand have become more diverse in terms of cultures, ethnicities and language backgrounds, clinical tutors have to directly facilitate the development of context-specific and client-focused communication skills for students who speak English as an additional language. We undertook a study which looked at the perceptions of new nursing graduates with English as an additional language (EAL) on the development of spoken language skills for the clinical workplace. As well as interviewing graduates, we spoke to four clinical tutors in order to elicit their views on the language development of EAL students in previous cohorts. This article reports on the themes which emerged from the interviews with the tutors. These include goal setting for communication, integrating students into nursing work, making assessment less stressful, and endorsing independent learning strategies. Based on their observations and on other published research we make some suggestions about ways both clinical tutors and EAL students within their teaching groups could be supported in the development of communication skills for clinical practice.

  17. Additive manufacture (3d printing) of plasma diagnostic components and assemblies for fusion experiments

    NASA Astrophysics Data System (ADS)

    Sieck, Paul; Woodruff, Simon; Stuber, James; Romero-Talamas, Carlos; Rivera, William; You, Setthivoine; Card, Alexander

    2015-11-01

    Additive manufacturing (or 3D printing) is now becoming sufficiently accurate with a large range of materials for use in printing sensors needed universally in fusion energy research. Decreasing production cost and significantly lowering design time of energy subsystems would realize significant cost reduction for standard diagnostics commonly obtained through research grants. There is now a well-established set of plasma diagnostics, but these expensive since they are often highly complex and require customization, sometimes pace the project. Additive manufacturing (3D printing) is developing rapidly, including open source designs. Basic components can be printed for (in some cases) less than 1/100th costs of conventional manufacturing. We have examined the impact that AM can have on plasma diagnostic cost by taking 15 separate diagnostics through an engineering design using Conventional Manufacturing (CM) techniques to determine costs of components and labor costs associated with getting the diagnostic to work as intended. With that information in hand, we set about optimizing the design to exploit the benefits of AM. Work performed under DOE Contract DE-SC0011858.

  18. Cell lineage tracing in the developing enteric nervous system: superstars revealed by experiment and simulation

    PubMed Central

    Cheeseman, Bevan L.; Zhang, Dongcheng; Binder, Benjamin J.; Newgreen, Donald F.; Landman, Kerry A.

    2014-01-01

    Cell lineage tracing is a powerful tool for understanding how proliferation and differentiation of individual cells contribute to population behaviour. In the developing enteric nervous system (ENS), enteric neural crest (ENC) cells move and undergo massive population expansion by cell division within self-growing mesenchymal tissue. We show that single ENC cells labelled to follow clonality in the intestine reveal extraordinary and unpredictable variation in number and position of descendant cells, even though ENS development is highly predictable at the population level. We use an agent-based model to simulate ENC colonization and obtain agent lineage tracing data, which we analyse using econometric data analysis tools. In all realizations, a small proportion of identical initial agents accounts for a substantial proportion of the total final agent population. We term these individuals superstars. Their existence is consistent across individual realizations and is robust to changes in model parameters. This inequality of outcome is amplified at elevated proliferation rate. The experiments and model suggest that stochastic competition for resources is an important concept when understanding biological processes which feature high levels of cell proliferation. The results have implications for cell-fate processes in the ENS. PMID:24501272

  19. Assessment of quality of platelets preserved in plasma and platelet additive solution: A Malaysian experience

    PubMed Central

    Mokhtar, Munirah Binti; Hashim, Hasna Binti; Joshi, Sanmukh R

    2016-01-01

    Background: A use of platelet additives solution (PAS) improves storage conditions so as to give increased shelf life to platelets and to maintain hemostatic function. Objective: The present study was aimed to compare in vitro quality of platelet rich plasma (PRP)-derived platelet concentrate (PC) during extended period of storage in plasma and in additive solution (Composol PS and Fresenius). Study Design: Randomized 19 PCs each were used in the study for plasma and PAS as the storage medium. The measurement parameters, including pH, total white blood cell (WBC) count, total platelet count, and platelet activation rate, were studied on day 1, day 5, and day 8 of the storage period. The sterility test was carried out on the eighth day of storage. Results: pH of PC suspended in PAS was significantly lower as compared to that in plasma (P < 0.001) for all the three days of sampling. The WBC count, both in plasma and in PAS, showed an acceptable values of being <0.2 Χ 109 /unit during the storage period. Platelet count in PAS was higher as compared to that in plasma, though it was not statistically significant. While both the groups showed increased platelet activation rate during the storage, the PCs suspended in PAS showed significantly higher platelet activation rate (p0.001). Results from sterility test showed no bacterial growth in the PCs in both the groups. Conclusion: Most parameters studied on platelet storage in suspending medium of native plasma and PAS remained well within the acceptable limits. However, the pH values and platelet activation rate significantly differed in PAS as compared with plasma. PMID:27011678

  20. Summary and overview of the CYCLOPS P addition Lagrangian experiment in the Eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Krom, M. D.; Thingstad, T. F.; Brenner, S.; Carbo, P.; Drakopoulos, P.; Fileman, T. W.; Flaten, G. A. F.; Groom, S.; Herut, B.; Kitidis, V.; Kress, N.; Law, C. S.; Liddicoat, M. I.; Mantoura, R. F. C.; Pasternak, A.; Pitta, P.; Polychronaki, T.; Psarra, S.; Rassoulzadegan, F.; Skjoldal, E. F.; Spyres, G.; Tanaka, T.; Tselepides, A.; Wassmann, P.; Wexels Riser, C.; Woodward, E. M. S.; Zodiatis, G.; Zohary, T.

    2005-11-01

    CYCLOPS was a European Framework 5 program to further our understanding of phosphorus cycling in the Eastern Mediterranean. The core of CYCLOPS was a Lagrangian experiment in which buffered phosphoric acid was added to a <4×4 km patch of water together with SF 6 as the inert tracer. The patch was followed for nine days in total. Results obtained prior to the experiment showed that the system was typically ultra-oligotrophic and P-starved with DON:DOP, PON:POP and DIN:DIP all having ratios greatly in excess of 16:1 in surface waters. To our surprise, we found that although the added phosphate was rapidly taken up by the microbial biota, there was a small but significant decrease in chlorophyll a and no increase in primary production, together with an increase in heterotrophic bacterial activity, ciliate numbers and in the gut fullness and egg numbers in the zooplankton community. A microcosm experiment carried out using within-patch and out-of-patch water showed that the phytoplankton community were N and P co-limited while the bacteria and micrograzers were P-limited. Thus this system tends to N and P co-limitation of phytoplankton productivity in summer possibly caused by bioavailable DIN being converted into non-bioavailable forms of DON. On the basis of the data collected within the programme it was concluded that this behavior could be explained by three non-mutually exclusive processes described as (1) trophic by-pass in which the added phosphate gets directly to the grazing part of the predatory food chain from the heterotrophic bacteria bypassing the phytoplankton compartment phosphate, (2) trophic tunnelling in which phosphate is rapidly taken up by both phytoplankton and bacteria via rapid luxury consumption. This causes an immediate change in the phosphorus content but not the abundance of the prey organisms. The added P then "reappears" as responses at the predator level much more rapidly than expected, and (3) mixotrophic by-pass in which inorganic

  1. [Requirements for drug approval and additional benefits assessment: Regulatory aspects and experiences].

    PubMed

    Broich, K; Löbker, W; Schulte, A; Beinlich, P; Müller, T

    2016-04-01

    The early assessment of benefits of newly approved drugs with novel active substances or new applications, which came into force on 1 January 2011 still represents a challenge to all parties involved. This article highlights the definitions, regulatory requirements and interaction between drug marketing approval and early assessment of benefits in Germany. The constellation of an extensively harmonized European and even international drug authorization process with a predominantly national regulation of drug reimbursement situation inevitably causes friction, which could be markedly reduced through early joint advisory discussions during the planning phase for pivotal clinical trials. During the year 2015 the Federal Institute for Drugs and Medical Devices (BfArM) carried out 300 scientific advice procedures of which 34 were concerned with applications in the field of indications for the central nervous system (CNS). In comparison 98 advisory meetings were held by the Federal Joint Committee (G-BA) of which the BfArM provided advice in 12 instances and in 2 cases on CNS indications. Study design, endpoints and appropriate comparative therapies are the key issues in exchanges and discussions between the BfArM, the G‑BA and applicants. Under these aspects the BfArM and G‑BA promote an early and consistent involvement in early advice procedures regarding the prerequisites for drug approval and assessment of additional benefits.

  2. Effects of biochar addition to soil on nitrogen fluxes in a winter wheat lysimeter experiment

    NASA Astrophysics Data System (ADS)

    Hüppi, Roman; Leifeld, Jens; Neftel, Albrecht; Conen, Franz; Six, Johan

    2014-05-01

    Biochar is a carbon-rich, porous residue from pyrolysis of biomass that potentially increases crop yields by reducing losses of nitrogen from soils and/or enhancing the uptake of applied fertiliser by the crops. Previous research is scarce about biochar's ability to increase wheat yields in temperate soils or how it changes nitrogen dynamics in the field. In a lysimeter system with two different soils (sandy/silt loam) nitrogen fluxes were traced by isotopic 15N enriched fertiliser to identify changes in nitrous oxide emissions, leaching and plant uptake after biochar addition. 20t/ha woodchip-waste biochar (pH=13) was applied to these soils in four lysimeters per soil type; the same number of lysimeters served as a control. The soils were cropped with winter wheat during the season 2012/2013. 170 kg-N/ha ammonium nitrate fertiliser with 10% 15N was applied in 3 events during the growing season and 15N concentrations where measured at different points in time in plant, soil, leachate and emitted nitrous oxide. After one year the lysimeter system showed no difference between biochar and control treatment in grain- and straw yield or nitrogen uptake. However biochar did reduce nitrous oxide emissions in the silt loam and losses of nitrate leaching in sandy loam. This study indicates potential reduction of nitrogen loss from cropland soil by biochar application but could not confirm increased yields in an intensive wheat production system.

  3. Spectroscopic properties of photosystem II core complexes from Thermosynechococcus elongatus revealed by single-molecule experiments.

    PubMed

    Brecht, Marc; Skandary, Sepideh; Hellmich, Julia; Glöckner, Carina; Konrad, Alexander; Hussels, Martin; Meixner, Alfred J; Zouni, Athina; Schlodder, Eberhard

    2014-06-01

    In this study we use a combination of absorption, fluorescence and low temperature single-molecule spectroscopy to elucidate the spectral properties, heterogeneities and dynamics of the chlorophyll a (Chla) molecules responsible for the fluorescence emission of photosystem II core complexes (PS II cc) from the cyanobacterium Thermosynechococcus elongatus. At the ensemble level, the absorption and fluorescence spectra show a temperature dependence similar to plant PS II. We report emission spectra of single PS II cc for the first time; the spectra are dominated by zero-phonon lines (ZPLs) in the range between 680 and 705nm. The single-molecule experiments show unambiguously that different emitters and not only the lowest energy trap contribute to the low temperature emission spectrum. The average emission spectrum obtained from more than hundred single complexes shows three main contributions that are in good agreement with the reported bands F685, F689 and F695. The intensity of F695 is found to be lower than in conventional ensemble spectroscopy. The reason for the deviation might be due to the accumulation of triplet states on the red-most chlorophylls (e.g. Chl29 in CP47) or on carotenoids close to these long-wavelength traps by the high excitation power used in the single-molecule experiments. The red-most emitter will not contribute to the fluorescence spectrum as long as it is in the triplet state. In addition, quenching of fluorescence by the triplet state may lead to a decrease of long-wavelength emission.

  4. Nitrate removal in stream ecosystems measured by 15N addition experiments: 2. Denitrification

    SciTech Connect

    Mulholland, Patrick J; Hall, Robert; Sobota, Daniel; Dodds, Walter; Findlay, Stuart; Grimm, Nancy; Hamilton, Stephen; McDowell, William; O'Brien, Jon; Tank, Jennifer; Ashkenas, Linda; Cooper, Lee W; Dahm, Cliff; Gregory, Stanley; Johnson, Sherri; Meyer, Judy; Peterson, Bruce; Poole, Geoff; Valett, H. Maurice; Webster, Jackson; Arango, Clay; Beaulieu, Jake; Bernot, Melody; Burgin, Amy; Crenshaw, Chelsea; Helton, Ashley; Johnson, Laura; Niederlehner, Bobbie; Potter, Jody; Sheibley, Rich; Thomas, Suzanne

    2009-01-01

    We measured denitrification rates using a field {sup 15}N-NO{sub 3}{sup -} tracer-addition approach in a large, cross-site study of nitrate uptake in reference, agricultural, and suburban-urban streams. We measured denitrification rates in 49 of 72 streams studied. Uptake length due to denitrification (S{sub Wden}) ranged from 89 m to 184 km (median of 9050 m) and there were no significant differences among regions or land-use categories, likely because of the wide range of conditions within each region and land use. N{sub 2} production rates far exceeded N{sub 2}O production rates in all streams. The fraction of total NO{sub 3}{sup -} removal from water due to denitrification ranged from 0.5% to 100% among streams (median of 16%), and was related to NH{sub 4}{sup +} concentration and ecosystem respiration rate (ER). Multivariate approaches showed that the most important factors controlling S{sub Wden} were specific discharge (discharge/width) and NO{sub 3}{sup -} concentration (positive effects), and ER and transient storage zones (negative effects). The relationship between areal denitrification rate (U{sub den}) and NO{sub 3}{sup -} concentration indicated a partial saturation effect. A power function with an exponent of 0.5 described this relationship better than a Michaelis-Menten equation. Although U{sub den} increased with increasing NO{sub 3}{sup -} concentration, the efficiency of NO{sub 3}{sup -} removal from water via denitrification declined, resulting in a smaller proportion of streamwater NO{sub 3}{sup -} load removed over a given length of stream. Regional differences in stream denitrification rates were small relative to the proximate factors of NO{sub 3}{sup -} concentration and ecosystem respiration rate, and land use was an important but indirect control on denitrification in streams, primarily via its effect on NO{sub 3}{sup -} concentration.

  5. Nitrate removal in stream ecosystems measured by 15N addition experiments: Denitrification

    USGS Publications Warehouse

    Mulholland, P.J.; Hall, R.O.; Sobota, D.J.; Dodds, W.K.; Findlay, S.E.G.; Grimm, N. B.; Hamilton, S.K.; McDowell, W.H.; O'Brien, J. M.; Tank, J.L.; Ashkenas, L.R.; Cooper, L.W.; Dahm, Clifford N.; Gregory, S.V.; Johnson, S.L.; Meyer, J.L.; Peterson, B.J.; Poole, G.C.; Valett, H.M.; Webster, J.R.; Arango, C.P.; Beaulieu, J.J.; Bernot, M.J.; Burgin, A.J.; Crenshaw, C.L.; Helton, A.M.; Johnson, L.T.; Niederlehner, B.R.; Potter, J.D.; Sheibley, R.W.; Thomasn, S.M.

    2009-01-01

    We measured denitrification rates using a field 15N-NO- 3 tracer-addition approach in a large, cross-site study of nitrate uptake in reference, agricultural, and suburban-urban streams. We measured denitrification rates in 49 of 72 streams studied. Uptake length due to denitrification (SWden) ranged from 89 m to 184 km (median of 9050 m) and there were no significant differences among regions or land-use categories, likely because of the wide range of conditions within each region and land use. N2 production rates far exceeded N2O production rates in all streams. The fraction of total NO-3 removal from water due to denitrification ranged from 0.5% to 100% among streams (median of 16%), and was related to NHz 4 concentration and ecosystem respiration rate (ER). Multivariate approaches showed that the most important factors controlling SWden were specific discharge (discharge / width) and NO-3 concentration (positive effects), and ER and transient storage zones (negative effects). The relationship between areal denitrification rate (Uden) and NO- 3 concentration indicated a partial saturation effect. A power function with an exponent of 0.5 described this relationship better than a Michaelis-Menten equation. Although Uden increased with increasing NO- 3 concentration, the efficiency of NO-3 removal from water via denitrification declined, resulting in a smaller proportion of streamwater NO-3 load removed over a given length of stream. Regional differences in stream denitrification rates were small relative to the proximate factors of NO-3 concentration and ecosystem respiration rate, and land use was an important but indirect control on denitrification in streams, primarily via its effect on NO-3 concentration. ?? 2009.

  6. Experience-dependent hemispheric specialization of letters and numbers is revealed in early visual processing.

    PubMed

    Park, Joonkoo; Chiang, Crystal; Brannon, Elizabeth M; Woldorff, Marty G

    2014-10-01

    Recent fMRI research has demonstrated that letters and numbers are preferentially processed in distinct regions and hemispheres in the visual cortex. In particular, the left visual cortex preferentially processes letters compared with numbers, whereas the right visual cortex preferentially processes numbers compared with letters. Because letters and numbers are cultural inventions and are otherwise physically arbitrary, such a double dissociation is strong evidence for experiential effects on neural architecture. Here, we use the high temporal resolution of ERPs to investigate the temporal dynamics of the neural dissociation between letters and numbers. We show that the divergence between ERP traces to letters and numbers emerges very early in processing. Letters evoked greater N1 waves (latencies 140-170 msec) than did numbers over left occipital channels, whereas numbers evoked greater N1s than letters over the right, suggesting letters and numbers are preferentially processed in opposite hemispheres early in visual encoding. Moreover, strings of letters, but not single letters, elicited greater P2 ERP waves (starting around 250 msec) than numbers did over the left hemisphere, suggesting that the visual cortex is tuned to selectively process combinations of letters, but not numbers, further along in the visual processing stream. Additionally, the processing of both of these culturally defined stimulus types differentiated from similar but unfamiliar visual stimulus forms (false fonts) even earlier in the processing stream (the P1 at 100 msec). These findings imply major cortical specialization processes within the visual system driven by experience with reading and mathematics.

  7. Impacts of Asian Dust and Haze Particles Addition on Phytoplankton in Incubation Experiments in the Yellow Sea of China

    NASA Astrophysics Data System (ADS)

    Gao, H.; Zhang, C.; Liu, Y.; Shi, J.; Yao, X.

    2014-12-01

    Atmospheric deposition (AD) induced by dust events and air pollutants has been considered as an important source of bio-available nutrients such as N, P, Si and trace metals (e.g., Fe, Cu, Pb) to the oceans. The coastal seas of China are severely affected by AD from Asian dust events and haze episodes, especially in spring and winter. In this study, several on-board incubation experiments were performed in the Yellow Sea of China during 2011 - 2014, to explore the responses of micro-, nano- and pico-phytoplankton to various combinations of Asian dust, nutrients and haze particles by measuring the size-fractionated chlorophyll a (Chl a) concentration. In the experiments of Asian dust addition, the concentration of Chl a and the conversion efficiency index of N into Chl a increased by up to ~40 % and ~30 %, respectively, compared to the control, showing enhancement effects on the growth of phytoplankton. The addition of haze particles exhibited more obvious promotions of pico-phytoplankton growth, but more severe inhibitions of micro-phytoplankton growth than other treatments. The incubation experiments conducted in the Yellow Sea also indicated P limitation variations in spring and summer. It was inferred that both Asian dust and haze particles additions had significant impacts on the growth and structure of phytoplankton by modulating the limiting factors.

  8. Brain spectrin (fodrin) interacts with phospholipids as revealed by intrinsic fluorescence quenching and monolayer experiments.

    PubMed Central

    Diakowski, W; Prychidny, A; Swistak, M; Nietubyć, M; Białkowska, K; Szopa, J; Sikorski, A F

    1999-01-01

    We demonstrate that phospholipid vesicles affect the intrinsic fluorescence of isolated brain spectrin. In the present studies we tested the effects of vesicles prepared from phosphatidylcholine (PtdCho) alone, in addition to vesicles containing PtdCho mixed with other phospholipids [phosphatidylethanolamine (PtdEtn) and phosphatidylserine] as well as from total lipid mixture extracted from brain membrane. The largest effect was observed with PtdEtn/PtdCho (3:2 molar ratio) vesicles; the effect was markedly smaller when vesicles were prepared from egg yolk PtdCho alone. Brain spectrin injected into a subphase induced a substantial increase in the surface pressure of monolayers prepared from phospholipids. Results obtained with this technique indicated that the largest effect is again observed with monolayers prepared from a PtdEtn/PtdCho mixture. The greatest effect was observed when the monolayer contained 50-60% PtdEtn in a PtdEtn/PtdCho mixture. This interaction occurred at salt and pH optima close to physiological conditions (0.15 M NaCl, pH7.5). Experiments with isolated spectrin subunits indicated that the effect of the beta subunit on the monolayer surface pressure resembled that measured with the whole molecule. Similarly to erythrocyte spectrin-membrane interactions, brain spectrin interactions with PtdEtn/PtdCho monolayer were competitively inhibited by isolated erythrocyte ankyrin. This also suggests that the major phospholipid-binding site is located in the beta subunit and indicates the possible physiological significance of this interaction. PMID:9931302

  9. Experience Sampling Methodology reveals similarities in the experience of passage of time in young and elderly adults.

    PubMed

    Droit-Volet, Sylvie; Wearden, John H

    2015-03-01

    Many people accept the idea that time seems to pass more quickly as they get older, as if this is a psychological reality. However, systematic investigations of differences in judgments of passage of time between young and elderly people are very rare and contradictory. The present study examined the experience of passage of time in daily life in young and elderly people using Experience Sampling Methodology (ESM), with 8 alerts per day for 5 days being delivered by smartphones. At each alert, a short questionnaire was filled in, asking questions about passage of present time, affective state, arousal level, and attention to current activities, among others. Our ESM study found no difference between the young and the old participants in the judgment of passage of present time. Irrespective of the participants' age, the experience of passage of time in every-day life was significantly related to affective states and current activities when they captured attention.

  10. Using Negative Emotions to Trace the Experience of Borderline Personality Pathology: Interconnected Relationships Revealed in an Experience Sampling Study.

    PubMed

    Law, Mary Kate; Fleeson, William; Arnold, Elizabeth Mayfield; Furr, R Michael

    2016-02-01

    While emotional difficulties are highly implicated in borderline personality disorder (BPD), the dynamic relationships between emotions and BPD symptoms that occur in everyday life are unknown. The current paper examined the function of negative emotions as they relate to BPD symptoms in real time. Experience sampling methodology with 281 participants measured negative emotions and borderline symptoms, expressed as a spectrum of experiences, five times daily for two weeks. Overall, having a BDP diagnosis was associated with experiencing more negative emotions. Multilevel modeling supported positive concurrent relationships between negative emotions and BPD symptoms. Lagged models showed that even after 3 hours negative emotions and several symptoms continued to influence each other. Therefore, results indicated that negative emotions and BPD symptoms are intricately related; some evidenced long-lasting relationships. This research supports emotion-symptom contingencies within BPD and provides insight regarding the reactivity and functionality of negative emotions in borderline pathology.

  11. Calcium nitrate addition to control the internal load of phosphorus from sediments of a tropical eutrophic reservoir: microcosm experiments.

    PubMed

    Yamada, T M; Sueitt, A P E; Beraldo, D A S; Botta, C M R; Fadini, P S; Nascimento, M R L; Faria, B M; Mozeto, A A

    2012-12-01

    The main objective of this study was to perform laboratory experiments on calcium nitrate addition to sediments of a tropical eutrophic urban reservoir (Ibirité reservoir, SE Brazil) to immobilize the reactive soluble phosphorus (RSP) and to evaluate possible geochemical changes and toxic effects caused by this treatment. Reductions of 75 and 89% in the concentration of RSP were observed in the water column and interstitial water, respectively, after 145 days of nitrate addition. The nitrate application increased the rate of autotrophic denitrification, causing a consumption of 98% of the added nitrate and oxidation of 99% of the acid volatile sulfide. As a consequence, there were increases in the sulfate and iron (II) concentrations in the sediment interstitial water and water column, as well as changes in the copper speciation in the sediments. Toxicity tests initially indicated that the high concentrations of nitrate and nitrite in the sediment interstitial water (up to 2300 mg L(-1) and 260 mg L(-1), respectively) were the major cause of mortality of Ceriodaphnia silvestrii and Chironomus xanthus. However, at the end of the experiment, the sediment toxicity was completely removed and a reduction in the 48 h-EC50 of the water was also observed. Based on these results we can say that calcium nitrate treatment proved to be a valuable tool in remediation of eutrophic aquatic ecosystems leading to conditions that can support a great diversity of organisms after a restoration period.

  12. Motor imagery of locomotion with an additional load: actual load experience does not affect differences between physical and mental durations.

    PubMed

    Munzert, Jörn; Blischke, Klaus; Krüger, Britta

    2015-03-01

    Motor imagery relies strongly on motor representations. Currently, it is widely accepted that both the imagery and execution of actions share the same neural representations (Jeannerod, Neuroimage 14:S103-S109, 2001). Comparing mental with actual movement durations opens a window through which to examine motor representations and how they relate to cognitive motor processes. The present experiment examined mental durations reported by participants standing upright who imagined walking either with or without an additional load while actually carrying or not carrying that same load. Results showed a robust effect of longer durations when imagining the additional load during mental walking, whereas physical walking with an additional load did not extend movement durations accordingly. However, experiencing an actual load during imagery did not influence mental durations substantially. This dissociation of load-related effects can be interpreted as being due to an interaction of motor processes and their cognitive representation along with a reduction in neural activity in vestibular and somatosensory areas during imagery of locomotion. It is argued that this effect might be specific to locomotion and not generalize to a broader range of movements.

  13. Proteome analysis reveals differential expression of proteins involved in triacylglycerol accumulation by Rhodococcus jostii RHA1 after addition of methyl viologen.

    PubMed

    Dávila Costa, José Sebastián; Silva, Roxana A; Leichert, Lars; Alvarez, Héctor M

    2017-03-01

    Rhodococcus jostii RHA1 is able to degrade toxic compounds and accumulate high amounts of triacylglycerols (TAG) upon nitrogen starvation. These NADPH-dependent processes are essential for the adaptation of rhodococci to fluctuating environmental conditions. In this study, we used an MS-based, label-free and quantitative proteomic approach to better understand the integral response of R. jostii RHA1 to the presence of methyl viologen (MV) in relation to the synthesis and accumulation of TAG. The addition of MV promoted a decrease of TAG accumulation in comparison to cells cultivated under nitrogen-limiting conditions in the absence of this pro-oxidant. Proteomic analyses revealed that the abundance of key proteins of fatty acid biosynthesis, the Kennedy pathway, glyceroneogenesis and methylmalonyl-CoA pathway, among others, decreased in the presence of MV. In contrast, some proteins involved in lipolysis and β-oxidation of fatty acids were upregulated. Some metabolic pathways linked to the synthesis of NADPH remained activated during oxidative stress as well as under nitrogen starvation conditions. Additionally, exposure to MV resulted in the activation of complete antioxidant machinery comprising superoxide dismutases, catalases, mycothiol biosynthesis, mycothione reductase and alkyl hydroperoxide reductases, among others. Our study suggests that oxidative stress response affects TAG accumulation under nitrogen-limiting conditions through programmed molecular mechanisms when both stresses occur simultaneously.

  14. Revealing the full extent of households' experiences of HIV and AIDS in rural South Africa.

    PubMed

    Hosegood, Victoria; Preston-Whyte, Eleanor; Busza, Joanna; Moitse, Sindile; Timaeus, Ian M

    2007-09-01

    Households experience HIV and AIDS in a complex and changing set of environments. These include health and welfare treatment and support services, HIV-related stigma and discrimination, and individual and household social and economic circumstances. This paper documents the experiences of 12 households directly affected by HIV and AIDS in rural KwaZulu Natal, South Africa, between 2002 and 2004. The households were observed during repeated visits over a period of more than a year by ethnographically trained researchers. Field notes were analysed using thematic content analysis to identify themes and sub-themes. This paper focuses on three dimensions of household experience of HIV and AIDS that have received little attention in HIV and AIDS impact studies. First, that experience of HIV and AIDS is cumulative. In an area where population surveys report HIV prevalence rates of over 20% in adults, many households face multiple episodes of HIV-related illness and AIDS deaths. We describe how these challenges affect perceptions and responses within and outside households. Second, while over 50% of all adult deaths are due to AIDS, households continue to face other causes of illness and death. We show how these other causes compound the impact of AIDS, particularly where the deceased was the main income earner and/or primary carer for young children. Third, HIV-related illness and AIDS deaths of household members are only part of the households' cumulative experience of HIV and AIDS. Illness and death of non-household members, for example, former partners who are parents of children within the households or relatives who provide financial support, also impact negatively on households. We also discuss how measuring multiple episodes of illness and deaths can be recorded in household surveys in order to improve quantitative assessments of the impact of HIV and AIDS.

  15. Magnetic force microscopy reveals meta-stable magnetic domain states that prevent reliable absolute palaeointensity experiments.

    PubMed

    de Groot, Lennart V; Fabian, Karl; Bakelaar, Iman A; Dekkers, Mark J

    2014-08-22

    Obtaining reliable estimates of the absolute palaeointensity of the Earth's magnetic field is notoriously difficult. The heating of samples in most methods induces magnetic alteration--a process that is still poorly understood, but prevents obtaining correct field values. Here we show induced changes in magnetic domain state directly by imaging the domain configurations of titanomagnetite particles in samples that systematically fail to produce truthful estimates. Magnetic force microscope images were taken before and after a heating step typically used in absolute palaeointensity experiments. For a critical temperature (250 °C), we observe major changes: distinct, blocky domains before heating change into curvier, wavy domains thereafter. These structures appeared unstable over time: after 1-year of storage in a magnetic-field-free environment, the domain states evolved into a viscous remanent magnetization state. Our observations qualitatively explain reported underestimates from otherwise (technically) successful experiments and therefore have major implications for all palaeointensity methods involving heating.

  16. Field-scale experiments reveal persistent yield gaps in low-input and organic cropping systems.

    PubMed

    Kravchenko, Alexandra N; Snapp, Sieglinde S; Robertson, G Philip

    2017-01-31

    Knowledge of production-system performance is largely based on observations at the experimental plot scale. Although yield gaps between plot-scale and field-scale research are widely acknowledged, their extent and persistence have not been experimentally examined in a systematic manner. At a site in southwest Michigan, we conducted a 6-y experiment to test the accuracy with which plot-scale crop-yield results can inform field-scale conclusions. We compared conventional versus alternative, that is, reduced-input and biologically based-organic, management practices for a corn-soybean-wheat rotation in a randomized complete block-design experiment, using 27 commercial-size agricultural fields. Nearby plot-scale experiments (0.02-ha to 1.0-ha plots) provided a comparison of plot versus field performance. We found that plot-scale yields well matched field-scale yields for conventional management but not for alternative systems. For all three crops, at the plot scale, reduced-input and conventional managements produced similar yields; at the field scale, reduced-input yields were lower than conventional. For soybeans at the plot scale, biological and conventional managements produced similar yields; at the field scale, biological yielded less than conventional. For corn, biological management produced lower yields than conventional in both plot- and field-scale experiments. Wheat yields appeared to be less affected by the experimental scale than corn and soybean. Conventional management was more resilient to field-scale challenges than alternative practices, which were more dependent on timely management interventions; in particular, mechanical weed control. Results underscore the need for much wider adoption of field-scale experimentation when assessing new technologies and production-system performance, especially as related to closing yield gaps in organic farming and in low-resourced systems typical of much of the developing world.

  17. Field-scale experiments reveal persistent yield gaps in low-input and organic cropping systems

    PubMed Central

    Kravchenko, Alexandra N.; Snapp, Sieglinde S.; Robertson, G. Philip

    2017-01-01

    Knowledge of production-system performance is largely based on observations at the experimental plot scale. Although yield gaps between plot-scale and field-scale research are widely acknowledged, their extent and persistence have not been experimentally examined in a systematic manner. At a site in southwest Michigan, we conducted a 6-y experiment to test the accuracy with which plot-scale crop-yield results can inform field-scale conclusions. We compared conventional versus alternative, that is, reduced-input and biologically based–organic, management practices for a corn–soybean–wheat rotation in a randomized complete block-design experiment, using 27 commercial-size agricultural fields. Nearby plot-scale experiments (0.02-ha to 1.0-ha plots) provided a comparison of plot versus field performance. We found that plot-scale yields well matched field-scale yields for conventional management but not for alternative systems. For all three crops, at the plot scale, reduced-input and conventional managements produced similar yields; at the field scale, reduced-input yields were lower than conventional. For soybeans at the plot scale, biological and conventional managements produced similar yields; at the field scale, biological yielded less than conventional. For corn, biological management produced lower yields than conventional in both plot- and field-scale experiments. Wheat yields appeared to be less affected by the experimental scale than corn and soybean. Conventional management was more resilient to field-scale challenges than alternative practices, which were more dependent on timely management interventions; in particular, mechanical weed control. Results underscore the need for much wider adoption of field-scale experimentation when assessing new technologies and production-system performance, especially as related to closing yield gaps in organic farming and in low-resourced systems typical of much of the developing world. PMID:28096409

  18. Correlates of perceptual awareness in human primary auditory cortex revealed by an informational masking experiment.

    PubMed

    Wiegand, Katrin; Gutschalk, Alexander

    2012-05-15

    The presence of an auditory event may remain undetected in crowded environments, even when it is well above the sensory threshold. This effect, commonly known as informational masking, allows for isolating neural activity related to perceptual awareness, by comparing repetitions of the same physical stimulus where the target is either detected or not. Evidence from magnetoencephalography (MEG) suggests that auditory-cortex activity in the latency range 50-250 ms is closely coupled with perceptual awareness. Here, BOLD fMRI and MEG were combined to investigate at which stage in the auditory cortex neural correlates of conscious auditory perception can be observed. Participants were asked to indicate the perception of a regularly repeating target tone, embedded within a random multi-tone masking background. Results revealed widespread activation within the auditory cortex for detected target tones, which was delayed but otherwise similar to the activation of an unmasked control stimulus. The contrast of detected versus undetected targets revealed activity confined to medial Heschl's gyrus, where the primary auditory cortex is located. These results suggest that activity related to conscious perception involves the primary auditory cortex and is not restricted to activity in secondary areas.

  19. Lithospheric geometries revealed through electromagnetic imaging: SAMTEX (Southern Africa MagnetoTelluric Experiment) observations and results

    NASA Astrophysics Data System (ADS)

    Jones, A. G.; Muller, M. R.; Evans, R. L.; Miensopust, M. P.; Khoza, D. T.; Samtex Team

    2011-12-01

    The Southern African Magnetotelluric Experiment (SAMTEX) is imaging the properties and geometries of the lithosphere below southern Africa to depths of 200+ km. Electrical conductivity is highly sensitive to ambient temperature, and to the presence of an interconnected conducting phase, such as a solid phase like graphite or sulphides, a fluid phase like partial melt, or bound water through hydrogen diffusion. Thus, primary geometrical information can be readily obtained from lithospheric-scale MT experiments about the three-dimensional variation in conductivity that can be related to formation and deformation processes. One important piece of information easily obtained from MT data is the depth to the lithosphere-asthenosphere boundary (LAB), due to the sensitivity of conductivity to small fractions (<1%) of partial melt and/or of some hundreds of ppm of bound water. SAMTEX measurements have been made at a total of more than 750 MT sites over an area in excess of a million square kilometres, making it by far the largest-ever regional MT project undertaken. One of the most significant results from SAMTEX is the mapping of the LAB beneath the Archean cratons and bounding mobile belts of Southern Africa, particularly of the previously unknown regions of Namibia and Botswana. The LAB is shallow (150 km) beneath the mobile belts, deep (250 km) in the centres of the cratons, and transitional at the edges. Diamondiferous kimberlites are located primarily where lithosphere is transitional in thickness, or where there is a change in its anisotropy properties, both of which are craton edge effects. The electrical properties of the continental mantle derived from SAMTEX data can be compared with seismic ones derived from data from the South African Seismic Experiment (SASE) of the Kaapvaal Project. Generally there is very good predictive linear agreement between seismic velocity and log(conductivity), indicative of both being influenced by the same bulk property factors

  20. Underplating in the Himalaya-Tibet collision zone revealed by the Hi-CLIMB experiment.

    PubMed

    Nábelek, John; Hetényi, György; Vergne, Jérôme; Sapkota, Soma; Kafle, Basant; Jiang, Mei; Su, Heping; Chen, John; Huang, Bor-Shouh

    2009-09-11

    We studied the formation of the Himalayan mountain range and the Tibetan Plateau by investigating their lithospheric structure. Using an 800-kilometer-long, densely spaced seismic array, we have constructed an image of the crust and upper mantle beneath the Himalayas and the southern Tibetan Plateau. The image reveals in a continuous fashion the Main Himalayan thrust fault as it extends from a shallow depth under Nepal to the mid-crust under southern Tibet. Indian crust can be traced to 31 degrees N. The crust/mantle interface beneath Tibet is anisotropic, indicating shearing during its formation. The dipping mantle fabric suggests that the Indian mantle is subducting in a diffuse fashion along several evolving subparallel structures.

  1. Translocation experiments with butterflies reveal limits to enhancement of poleward populations under climate change

    PubMed Central

    Pelini, Shannon L.; Dzurisin, Jason D. K.; Prior, Kirsten M.; Williams, Caroline M.; Marsico, Travis D.; Sinclair, Brent J.; Hellmann, Jessica J.

    2009-01-01

    There is a pressing need to predict how species will change their geographic ranges under climate change. Projections typically assume that temperature is a primary fitness determinant and that populations near the poleward (and upward) range boundary are preadapted to warming. Thus, poleward, peripheral populations will increase with warming, and these increases facilitate poleward range expansions. We tested the assumption that poleward, peripheral populations are enhanced by warming using 2 butterflies (Erynnis propertius and Papilio zelicaon) that co-occur and have contrasting degrees of host specialization and interpopulation genetic differentiation. We performed a reciprocal translocation experiment between central and poleward, peripheral populations in the field and simulated a translocation experiment that included alternate host plants. We found that the performance of both central and peripheral populations of E. propertius were enhanced during the summer months by temperatures characteristic of the range center but that local adaptation of peripheral populations to winter conditions near the range edge could counteract that enhancement. Further, poleward range expansion in this species is prevented by a lack of host plants. In P. zelicaon, the fitness of central and peripheral populations decreased under extreme summer temperatures that occurred in the field at the range center. Performance in this species also was affected by an interaction of temperature and host plant such that host species strongly mediated the fitness of peripheral individuals under differing simulated temperatures. Altogether we have evidence that facilitation of poleward range shifts through enhancement of peripheral populations is unlikely in either study species. PMID:19549861

  2. Translocation experiments with butterflies reveal limits to enhancement of poleward populations under climate change.

    PubMed

    Pelini, Shannon L; Dzurisin, Jason D K; Prior, Kirsten M; Williams, Caroline M; Marsico, Travis D; Sinclair, Brent J; Hellmann, Jessica J

    2009-07-07

    There is a pressing need to predict how species will change their geographic ranges under climate change. Projections typically assume that temperature is a primary fitness determinant and that populations near the poleward (and upward) range boundary are preadapted to warming. Thus, poleward, peripheral populations will increase with warming, and these increases facilitate poleward range expansions. We tested the assumption that poleward, peripheral populations are enhanced by warming using 2 butterflies (Erynnis propertius and Papilio zelicaon) that co-occur and have contrasting degrees of host specialization and interpopulation genetic differentiation. We performed a reciprocal translocation experiment between central and poleward, peripheral populations in the field and simulated a translocation experiment that included alternate host plants. We found that the performance of both central and peripheral populations of E. propertius were enhanced during the summer months by temperatures characteristic of the range center but that local adaptation of peripheral populations to winter conditions near the range edge could counteract that enhancement. Further, poleward range expansion in this species is prevented by a lack of host plants. In P. zelicaon, the fitness of central and peripheral populations decreased under extreme summer temperatures that occurred in the field at the range center. Performance in this species also was affected by an interaction of temperature and host plant such that host species strongly mediated the fitness of peripheral individuals under differing simulated temperatures. Altogether we have evidence that facilitation of poleward range shifts through enhancement of peripheral populations is unlikely in either study species.

  3. Engineered deafness reveals that mouse courtship vocalizations do not require auditory experience.

    PubMed

    Mahrt, Elena J; Perkel, David J; Tong, Ling; Rubel, Edwin W; Portfors, Christine V

    2013-03-27

    Auditory experience during development is necessary for normal language acquisition in humans. Although songbirds, some cetaceans, and maybe bats may also be vocal learners, vocal learning has yet to be well established for a laboratory mammal. Mice are potentially an excellent model organism for studying mechanisms underlying vocal communication. Mice vocalize in different social contexts, yet whether they learn their vocalizations remains unresolved. To address this question, we compared ultrasonic courtship vocalizations emitted by chronically deaf and normal hearing adult male mice. We deafened CBA/CaJ male mice, engineered to express diphtheria toxin (DT) receptors in hair cells, by systemic injection of DT at postnatal day 2 (P2). By P9, almost all inner hair cells were absent and by P16 all inner and outer hair cells were absent in DTR mice. These mice did not show any auditory brainstem responses as adults. Wild-type littermates, also treated with DT at P2, had normal hair cells and normal auditory brainstem responses. We compared the temporal structure of vocalization bouts, the types of vocalizations, the patterns of syllables, and the acoustic features of each syllable type emitted by hearing and deaf males in the presence of a female. We found that almost all of the vocalization features we examined were similar in hearing and deaf animals. These findings indicate that mice do not need auditory experience during development to produce normal ultrasonic vocalizations in adulthood. We conclude that mouse courtship vocalizations are not acquired through auditory feedback-dependent learning.

  4. In Silico and In Vivo Experiments Reveal M-CSF Injections Accelerate Regeneration Following Muscle Laceration.

    PubMed

    Martin, Kyle S; Kegelman, Christopher D; Virgilio, Kelley M; Passipieri, Julianna A; Christ, George J; Blemker, Silvia S; Peirce, Shayn M

    2017-03-01

    Numerous studies have pharmacologically modulated the muscle milieu in the hopes of promoting muscle regeneration; however, the timing and duration of these interventions are difficult to determine. This study utilized a combination of in silico and in vivo experiments to investigate how inflammation manipulation improves muscle recovery following injury. First, we measured macrophage populations following laceration injury in the rat tibialis anterior (TA). Then we calibrated an agent-based model (ABM) of muscle injury to mimic the observed inflammation profiles. The calibrated ABM was used to simulate macrophage and satellite stem cell (SC) dynamics, and suggested that delivering macrophage colony stimulating factor (M-CSF) prior to injury would promote SC-mediated injury recovery. Next, we performed an experiment wherein 1 day prior to injury, we injected M-CSF into the rat TA muscle. M-CSF increased the number of macrophages during the first 4 days post-injury. Furthermore, treated muscles experienced a swifter increase in the appearance of PAX7(+) SCs and regenerating muscle fibers. Our study suggests that computational models of muscle injury provide novel insights into cellular dynamics during regeneration, and further, that pharmacologically altering inflammation dynamics prior to injury can accelerate the muscle regeneration process.

  5. Sighs, smiles, and worried glances: how the body reveals women caregivers' lived experiences of care to older adults.

    PubMed

    Silverman, Marjorie

    2013-08-01

    This article reports on findings from microethnographic research that examined the lived reality of women caregivers through detailed observation of their everyday, embodied experiences. The research, which was rooted in the trend in social gerontology to emphasize subjective experience, focused on five women who were providing care to an older adult with a chronic illness or impairment. Four of the five women were caring for a spouse; one was caring for a parent. Observing the women's daily realities revealed tensions and contradictions between their subjective lived experiences and the pressures of the system in which they were functioning. The data revealed a caregiver habitus characterized by the performance of emotional labor. Performance was visible through dissonance between the caregivers' verbal and nonverbal expressions, and pointed to a high degree of emotion and body management. The women consistently put aside their own needs, in what can be considered a divestment in health capital. There was also evidence of merging between the caregiver and care receiver, made visible through tandem movements. The findings lead to implications for practice and for future aging research, including the benefits of observation for enhancing understanding of clients' experiences.

  6. A cry from the darkness: women with severe mental illness in India reveal their experiences with sexual coercion.

    PubMed

    Chandra, Prabha S; Deepthivarma, S; Carey, Michael P; Carey, Kate B; Shalinianant, M P

    2003-01-01

    THIS STUDY used qualitative research methods to investigate the problem of sexual coercion among female psychiatric patients in India. Consecutive female admissions (n = 146) to the inpatient unit of a psychiatric hospital in southern India were screened regarding coercive sexual experiences. Women who reported coercion (n = 50; 34%) participated in a semi-structured interview to learn more about their experiences. Among these women, 24 (48%) reported that the perpetrator was their spouse, 13 (26%) identified a friend or acquaintance, and 10 (20%) identified a relative such as an uncle or cousin. Most experiences occurred in the women's homes. Thirty of the 50 coerced women (60%) reported that they had not disclosed their experience to anyone, and that they had not sought help. Women revealed a sense of helplessness, fear, and secrecy related to their experiences. The problem of sexual coercion is seldom addressed in mental health care in India; the prevalence and severity of such experiences warrant immediate clinical attention and continued research.

  7. Autonomy and Non-autonomy of Angiogenic Cell Movements Revealed by Experiment-Driven Mathematical Modeling.

    PubMed

    Sugihara, Kei; Nishiyama, Koichi; Fukuhara, Shigetomo; Uemura, Akiyoshi; Arima, Satoshi; Kobayashi, Ryo; Köhn-Luque, Alvaro; Mochizuki, Naoki; Suda, Toshio; Ogawa, Hisao; Kurihara, Hiroki

    2015-12-01

    Angiogenesis is a multicellular phenomenon driven by morphogenetic cell movements. We recently reported morphogenetic vascular endothelial cell (EC) behaviors to be dynamic and complex. However, the principal mechanisms orchestrating individual EC movements in angiogenic morphogenesis remain largely unknown. Here we present an experiment-driven mathematical model that enables us to systematically dissect cellular mechanisms in branch elongation. We found that cell-autonomous and coordinated actions governed these multicellular behaviors, and a cell-autonomous process sufficiently illustrated essential features of the morphogenetic EC dynamics at both the single-cell and cell-population levels. Through refining our model and experimental verification, we further identified a coordinated mode of tip EC behaviors regulated via a spatial relationship between tip and follower ECs, which facilitates the forward motility of tip ECs. These findings provide insights that enhance our mechanistic understanding of not only angiogenic morphogenesis, but also other types of multicellular phenomenon.

  8. Focus Groups Reveal Differences in Career Experiences Between Male and Female Geoscientists

    NASA Astrophysics Data System (ADS)

    Oconnell, S.; Frey, C. D.; Holmes, M.

    2003-12-01

    We conducted twelve telephone focus groups of geoscientists to discover what motivates geoscientists to enter our field and stay in our field. There were separate male and female groups from six different professional categories: administrators, full and associate professors, non-tenure track personnel, assistant professors, post-docs and PhD candidates, Bachelor's and Master's candidates. A total of 96 geoscientists participated. Specifically, respondents were asked what initially brought them into the geosciences. Three dominant themes emerged: the subject matter itself, undergraduate experiences, and relationships. A total of 51 responses to this question related to the subject matter itself. Approximately 61 percent (31) of those responses were given by male focus group participants. Across all focus groups, participants brought up issues such as a general appreciation of the outdoors, weather, rocks, and dinosaurs. Following closely behind the general subject matter is undergraduate events. Fifty-one responses mentioned something about undergraduate experiences such as an introductory class, a laboratory experience, or field experiences. While both female and male participants discussed the role of interpersonal relationships in their decision to become a geoscientist, females were slightly more likely to bring up relevant relationships (26 times for females compared to 21 for males). These relationships varied in both groups from a parent or grandparents influence to camping trips with professors. When respondents were asked whether they had ever considered leaving the geosciences and under what circumstances, there was a striking difference between males and females: males were far less likely to have ever considered leaving. Younger males were more likely to consider leaving than older geoscientists. They feel challenged by the financial constraints of graduate school and the time constraints of academic vs. family life. Many females considered leaving at

  9. An economic experiment reveals that humans prefer pool punishment to maintain the commons.

    PubMed

    Traulsen, Arne; Röhl, Torsten; Milinski, Manfred

    2012-09-22

    Punishment can stabilize costly cooperation and ensure the success of a common project that is threatened by free-riders. Punishment mechanisms can be classified into pool punishment, where the punishment act is carried out by a paid third party, (e.g. a police system or a sheriff), and peer punishment, where the punishment act is carried out by peers. Which punishment mechanism is preferred when both are concurrently available within a society? In an economic experiment, we show that the majority of subjects choose pool punishment, despite being costly even in the absence of defectors, when second-order free-riders, cooperators that do not punish, are also punished. Pool punishers are mutually enforcing their support for the punishment organization, stably trapping each other. Our experimental results show how organized punishment could have displaced individual punishment in human societies.

  10. Revealing Dissociative Electron Attachment Dynamics in Polyatomic Molecules Using Momentum Imaging Experiments and Electron Scattering Calculations

    NASA Astrophysics Data System (ADS)

    Belkacem, Ali; Slaughter, Daniel

    2015-05-01

    Understanding electron-driven chemical reactions is important for improving a variety of technological applications such as materials processing and the important role they play in the radiation damage in bulk matter. Furthermore, dissociative electron attachment often exhibits site-selective bond cleavage, which holds promise for prediction and precise control of electron-driven chemical reactions. Recent dynamical studies of these reactions have demonstrated that an understanding of anion dissociation dynamics beyond simple one-dimensional models is crucial in interpreting the measured fragment angular distributions. We combine ion fragment momentum imaging experiments with electron attachment entrance amplitude calculations to interrogate the non-Born-Oppenheimer dynamics of dissociative electron attachment in polyatomic molecules. We will report recent experimental developments in molecules of technological interest including methanol, methane and uracil. Work supported by Chemical Sciences, Geosciences and Biosciences division of BES/DOE.

  11. A phantom road experiment reveals traffic noise is an invisible source of habitat degradation

    PubMed Central

    Ware, Heidi E.; McClure, Christopher J. W.; Carlisle, Jay D.; Barber, Jesse R.

    2015-01-01

    Decades of research demonstrate that roads impact wildlife and suggest traffic noise as a primary cause of population declines near roads. We created a “phantom road” using an array of speakers to apply traffic noise to a roadless landscape, directly testing the effect of noise alone on an entire songbird community during autumn migration. Thirty-one percent of the bird community avoided the phantom road. For individuals that stayed despite the noise, overall body condition decreased by a full SD and some species showed a change in ability to gain body condition when exposed to traffic noise during migratory stopover. We conducted complementary laboratory experiments that implicate foraging-vigilance behavior as one mechanism driving this pattern. Our results suggest that noise degrades habitat that is otherwise suitable, and that the presence of a species does not indicate the absence of an impact. PMID:26324924

  12. Common garden experiments reveal uncommon responses across temperatures, locations, and species of ants.

    PubMed

    Pelini, Shannon L; Diamond, Sarah E; Maclean, Heidi; Ellison, Aaron M; Gotelli, Nicholas J; Sanders, Nathan J; Dunn, Robert R

    2012-12-01

    Population changes and shifts in geographic range boundaries induced by climate change have been documented for many insect species. On the basis of such studies, ecological forecasting models predict that, in the absence of dispersal and resource barriers, many species will exhibit large shifts in abundance and geographic range in response to warming. However, species are composed of individual populations, which may be subject to different selection pressures and therefore may be differentially responsive to environmental change. Asystematic responses across populations and species to warming will alter ecological communities differently across space. Common garden experiments can provide a more mechanistic understanding of the causes of compositional and spatial variation in responses to warming. Such experiments are useful for determining if geographically separated populations and co-occurring species respond differently to warming, and they provide the opportunity to compare effects of warming on fitness (survivorship and reproduction). We exposed colonies of two common ant species in the eastern United States, Aphaenogaster rudis and Temnothorax curvispinosus, collected along a latitudinal gradient from Massachusetts to North Carolina, to growth chamber treatments that simulated current and projected temperatures in central Massachusetts and central North Carolina within the next century. Regardless of source location, colonies of A. rudis, a keystone seed disperser, experienced high mortality and low brood production in the warmest temperature treatment. Colonies of T. curvispinosus from cooler locations experienced increased mortality in the warmest rearing temperatures, but colonies from the warmest locales did not. Our results suggest that populations of some common species may exhibit uniform declines in response to warming across their geographic ranges, whereas other species will respond differently to warming in different parts of their geographic

  13. Seasonal and interannual variations in total ozone revealed by the Nimbus-4 backscattered ultraviolet experiment

    NASA Technical Reports Server (NTRS)

    Hilsenrath, E.; Heath, D. F.; Schlesinger, B. M.

    1978-01-01

    The first two years of Backscattered Ultraviolet (BUV) ozone data from the Nimbus-4 spacecraft were reprocessed. The seasonal variations of total ozone for the period April 1970 to April 1972 are described using daily zonal means to 10 deg latitude zones and a time-latitude cross section. In addition, the BUV data are compared with analyzed Dobson data and with IRIS data also obtained from the Nimbus-4 spacecraft. A harmonic analysis was performed on the daily zonal means. Amplitudes, days of peaks, and percentage of variance were computed for annual and semi-annual waves and for higher harmonics of an annual period for the two years. Asymmetries are found in the annual waves in the two hemispheres, with a subtle interannual difference which may be due to changes in the general circulation. A significant semi-annual component is detected in the tropics for the first year, which appears to result from influences of the annual waves in the two hemispheres.

  14. Computational modeling and molecular physiology experiments reveal new insights into shoot branching in pea.

    PubMed

    Dun, Elizabeth A; Hanan, Jim; Beveridge, Christine A

    2009-11-01

    Bud outgrowth is regulated by the interplay of multiple hormones, including auxin, cytokinin, strigolactones, and an unidentified long-distance feedback signal that moves from shoot to root. The model of bud outgrowth regulation in pea (Pisum sativum) includes these signals and a network of five RAMOSUS (RMS) genes that operate in a shoot-root-shoot loop to regulate the synthesis of, and response to, strigolactones. The number of components in this network renders the integration of new and existing hypotheses both complex and cumbersome. A hypothesis-driven computational model was therefore developed to help understand regulation of shoot branching. The model evolved in parallel with stepwise laboratory research, helping to define and test key hypotheses. The computational model was used to verify new mechanisms involved in the regulation of shoot branching by confirming that the new hypotheses captured all relevant biological data sets. Based on cytokinin and RMS1 expression analyses, this model is extended to include subtle but important differences in the function of RMS3 and RMS4 genes in the shoot and rootstock. Additionally, this research indicates that a branch-derived signal upregulates RMS1 expression independent of the other feedback signal. Furthermore, we propose xylem-sap cytokinin promotes sustained bud outgrowth, rather than acting at the earlier stage of bud release.

  15. Structure of the Crust and Mantle Lithosphere underneath NW Namibia Revealed by the WALPASS Seismic Experiment

    NASA Astrophysics Data System (ADS)

    Yuan, X.; Jokat, W.; Weber, M. H.; Geissler, W.; Heit, B.; Eken, T.; Pandey, S.; Lushetile, B.; Hoffmann, K.

    2013-12-01

    The amphibian Walvis Ridge Passive-Source Seismic Experiment (WALPASS) have been operated for a period of two years from 2010 to 2012 in the area where the Walvis Ridge intersects the continental margin of northwestern Namibia. The deployment was intended to study the lithospheric and upper mantle structure in the ocean-continent transition area beneath the passive continental margin. The main idea is to find seismic anomalies related to the postulated hotspot track from the continent to the ocean along the Walvis Ridge that links the Etendeka continental flood-basalt province to the Tristan da Cunha hotspot in the mid Atlantic ocean. This could provide clues of the role of plume-lithosphere interaction during the continental break-up. We present here seismic structures of the crustal and mantle lithosphere in this geophysically little studied region using seismic methods including P and S receiver functions and shear wave splitting. The average crustal thickness in the continental Namibia is ~35 km with a relatively low Vp/Vs ratio of 1.7. Underneath the NE extension of the Walvis Ridge the crust is the thickest (45 km) with a high Vp/Vs ratio (>1.80). The thick crust and high Vp/Vs ratio beneath the Walvis Ridge are consistent with high Vp derived by controlled source seismics, implying a magmatic underplating. A low velocity zone in the mantle is observed at depths of 60-120 km, possibly representing the base of the lithosphere. The P-to-S converted phases at the 410 and 660 km discontinuities arrive 2-3 s earlier, indicating higher upper mantle velocities (+5%). Seismic anisotropy in the mantle derived by the SKS splitting exhibits a pattern of the plume and plate interaction.

  16. Determination of Unknown Concentrations of Sodium Acetate Using the Method of Standard Addition and Proton NMR: An Experiment for the Undergraduate Analytical Chemistry Laboratory

    ERIC Educational Resources Information Center

    Rajabzadeh, Massy

    2012-01-01

    In this experiment, students learn how to find the unknown concentration of sodium acetate using both the graphical treatment of standard addition and the standard addition equation. In the graphical treatment of standard addition, the peak area of the methyl peak in each of the sodium acetate standard solutions is found by integration using…

  17. The myth of the tear-shaped raindrop - a classroom experiment to reveal the truth

    NASA Astrophysics Data System (ADS)

    Teschl, Franz

    2013-04-01

    Water is fundamental to life on Earth and precipitation is the primarily source of freshwater. In large part precipitation reaches the Earth in the liquid form as raindrops. In Earth Sciences there are so many aspects to water and to rain in particular: storms, floods, landslides, droughts and still, there is a general misconception on the shape of such a common thing as a raindrop. These water drops - we all have seen them a thousand times. We see them at a leaking faucet just in the moment when a drop is released; we see them when a raindrop hits a water surface and on a windscreen. But when do we normally not observe them? - Right, on their path from the cloud to the ground. And on this journey they would not look like the ones we frequently see. Probably the picture of a leaking faucet is one reason why so many people would think of raindrops as streamlined teardrops. This myth is somehow subliminally advertised every day e.g. in the daily weather forecast where - more often than not - the symbol for rain is shown as a cloud with a few streamlined drops. In fact small raindrops are spherical and the bigger they get while falling through the atmosphere, the more they get flattened on the bottom - sometimes described as the top half of a hamburger bun. What props would you need to proof this fact in a classroom course? You can start off with a shaded classroom, a pipette filled with water, and a point-and-shoot camera with a permanent flash setting: Release a couple of drops by the pipette and try to catch at least one of them with the camera. Even if the drops have already a falling velocity of several meters per second it will be the flashlight that freezes the image. On these images the drops will be anything but tear-shaped. Sure enough, if you are not working e.g. in radar meteorology or related fields you need not necessarily care about raindrop shapes but this experiment can be a vivid example that invites students to have a closer look on something that

  18. Significant Change in Marine Plankton Structure and Carbon Production After the Addition of River Water in a Mesocosm Experiment.

    PubMed

    Fouilland, E; Trottet, A; Alves-de-Souza, C; Bonnet, D; Bouvier, T; Bouvy, M; Boyer, S; Guillou, L; Hatey, E; Jing, H; Leboulanger, C; Le Floc'h, E; Liu, H; Mas, S; Mostajir, B; Nouguier, J; Pecqueur, D; Rochelle-Newall, E; Roques, C; Salles, C; Tournoud, M-G; Vasseur, C; Vidussi, F

    2017-03-16

    Rivers are known to be major contributors to eutrophication in marine coastal waters, but little is known on the short-term impact of freshwater surges on the structure and functioning of the marine plankton community. The effect of adding river water, reducing the salinity by 15 and 30%, on an autumn plankton community in a Mediterranean coastal lagoon (Thau Lagoon, France) was determined during a 6-day mesocosm experiment. Adding river water brought not only nutrients but also chlorophyceans that did not survive in the brackish mesocosm waters. The addition of water led to initial increases (days 1-2) in bacterial production as well as increases in the abundances of bacterioplankton and picoeukaryotes. After day 3, the increases were more significant for diatoms and dinoflagellates that were already present in the Thau Lagoon water (mainly Pseudo-nitzschia spp. group delicatissima and Prorocentrum triestinum) and other larger organisms (tintinnids, rotifers). At the same time, the abundances of bacterioplankton, cyanobacteria, and picoeukaryote fell, some nutrients (NH4(+), SiO4(3-)) returned to pre-input levels, and the plankton structure moved from a trophic food web based on secondary production to the accumulation of primary producers in the mesocosms with added river water. Our results also show that, after freshwater inputs, there is rapid emergence of plankton species that are potentially harmful to living organisms. This suggests that flash flood events may lead to sanitary issues, other than pathogens, in exploited marine areas.

  19. The Immersive Virtual Reality Experience: A Typology of Users Revealed Through Multiple Correspondence Analysis Combined with Cluster Analysis Technique.

    PubMed

    Rosa, Pedro J; Morais, Diogo; Gamito, Pedro; Oliveira, Jorge; Saraiva, Tomaz

    2016-03-01

    Immersive virtual reality is thought to be advantageous by leading to higher levels of presence. However, and despite users getting actively involved in immersive three-dimensional virtual environments that incorporate sound and motion, there are individual factors, such as age, video game knowledge, and the predisposition to immersion, that may be associated with the quality of virtual reality experience. Moreover, one particular concern for users engaged in immersive virtual reality environments (VREs) is the possibility of side effects, such as cybersickness. The literature suggests that at least 60% of virtual reality users report having felt symptoms of cybersickness, which reduces the quality of the virtual reality experience. The aim of this study was thus to profile the right user to be involved in a VRE through head-mounted display. To examine which user characteristics are associated with the most effective virtual reality experience (lower cybersickness), a multiple correspondence analysis combined with cluster analysis technique was performed. Results revealed three distinct profiles, showing that the PC gamer profile is more associated with higher levels of virtual reality effectiveness, that is, higher predisposition to be immersed and reduced cybersickness symptoms in the VRE than console gamer and nongamer. These findings can be a useful orientation in clinical practice and future research as they help identify which users are more predisposed to benefit from immersive VREs.

  20. Age and School Experience as Factors in Rule Utilization: Use of a Simple Addition Rule. Final Report, Part 1.

    ERIC Educational Resources Information Center

    Goulet, L. R.

    This study attempted to investigate the effects of school experience on performance on visual perception tests involving line figures and forms. The subjects were 120 first grade students selected from two public schools in the same community. The experiment involved an Experimental Treatments X Age X Time of Testing factorial design. All subjects…

  1. Soil microbial biomass and community structure affected by repeated additions of sewage sludge in four Swedish long-term field experiments

    NASA Astrophysics Data System (ADS)

    Börjesson, G.; Kätterer, T.; Kirchmann, H.

    2012-04-01

    Soil organic matter is a key attribute of soil fertility. The pool of soil organic C can be increased, either by mineral fertilisers or by adding organic amendments such as sewage sludge. Sewage sludge has positive effects on agricultural soils through the supply of organic matter and essential plant nutrients, but sludge may also contain unwanted heavy metals, xenobiotic substances and pathogens. One obvious effect of long-term sewage sludge addition is a decrease in soil pH, caused by N mineralisation followed by nitrification, sulphate formation and presence of organic acids with the organic matter added. The objective of this study was to investigate the effect of sewage sludge on the microbial biomass and community structure. Materials and methods We analysed soil samples from four sites where sewage sludge has been repeatedly applied in long-term field experiments situated in different parts of Sweden; Ultuna (59°49'N, 17°39'E, started 1956), Lanna (58°21'N, 13°06'E, started 1997-98), Petersborg (55°32'N, 13°00'E, started 1981) and Igelösa (55°45'N, 13°18'E, started 1981). In these four experiments, at least one sewage sludge treatment is included in the experimental design. In the Ultuna experiment, all organic fertilisers, including sewage sludge, are applied every second year, corresponding to 4 ton C ha-1. The Lanna experiment has a similar design, with 8 ton dry matter ha-1 applied every second year. Lanna also has an additional treatment in which metal salts (Cd, Cu, Ni and Zn) are added together with sewage sludge. At Petersborg and Igelösa, two levels of sewage sludge (4 or 12 ton dry matter ha-1 every 4th year) are compared with three levels of NPK fertiliser (0 N, ½ normal N and normal N). Topsoil samples (0-20 cm depth) from the four sites were analysed for total C, total N, pH and PLFAs (phospholipid fatty acids). In addition, crop yields were recorded. Results At all four sites, sewage sludge has had a positive effect on crop yields

  2. Independent and additive contributions of postvictory testosterone and social experience to the development of the winner effect.

    PubMed

    Fuxjager, Matthew J; Oyegbile, Temitayo O; Marler, Catherine A

    2011-09-01

    The processes through which salient social experiences influence future behavior are not well understood. Winning fights, for example, can increase the odds of future victory, yet little is known about the internal mechanisms that underlie such winner effects. Here, we use the territorial California mouse (Peromyscus californicus) to investigate how the effects of postvictory testosterone (T) release and winning experience individually mediate positive changes in future winning ability and antagonistic behavior. Male mice were castrated and implanted with T capsules to maintain basal levels of this hormone. We found that males form a robust winner effect if they win three separate territorial disputes and experience a single T surge roughly 45 min after each encounter. Meanwhile, males exhibit only an intermediate winner effect if they either 1) acquire three previous wins but do not experience a change in postvictory T or 2) acquire no previous wins but experience three separate T pulses. The results indicate that the effect of postvictory T must be coupled with that of winning experience to trigger the maximum positive shift in winning ability, which highlights the importance of social context in the development of the winner effect. At the same time, however, postvictory T and winning experience are each capable of increasing future winning ability independently, and this finding suggests that these two factors drive plasticity in antagonistic behavior via distinct mechanistic channels. More broadly, our data offer insight into the possible ways in which various species might be able to adjust their behavioral repertoire in response to social interactions through mechanisms that are unlinked from the effects of gonadal steroid action.

  3. Reflections on Doctoral Supervision: Drawing from the Experiences of Students with Additional Learning Needs in Two Universities

    ERIC Educational Resources Information Center

    Collins, Bethan

    2015-01-01

    Supervision is an essential part of doctoral study, consisting of relationship and process aspects, underpinned by a range of values. To date there has been limited research specifically about disabled doctoral students' experiences of supervision. This paper draws on qualitative, narrative interviews about doctoral supervision with disabled…

  4. Examining the Influence of Additional Field-Based Experiences on Pre-Service Teachers and Their Perceived Ability to Teach

    ERIC Educational Resources Information Center

    Clark, Sarah K.

    2012-01-01

    In an attempt to analyse more closely the training experiences of pre-service teachers, the author conducted an exploratory quasi-experimental study at a university located in the Rocky Mountain region of the USA. All students who were enrolled in the same reading methods course (but enrolled in different sections) were invited to participate in…

  5. [Additional memory load causes changes in induced EEG beta-rhythm in experiments with a visual set formed to facial expression].

    PubMed

    Iakovenko, I A; Kozlov, M K; Cheremushkin, E A

    2012-01-01

    Subjects were divided into two equal groups 35 healthy subjects each. Formation of the visual set to facial emotion recognition was supplemented with two types of additional task: either visuospatial (to find a target stimulus among others) or verbal (to tell a word from a pseudoword). The results of the experiments were compared to those obtained in similar experiments without the memory load. Changes in the EEG beta rhythm during visual set forming and testing were studied. The EEG was analyzed by wavelet transformation. Changes in the mean level, maximum and latency of the maximum of wavelet coefficient were rated at different stages of the experiment. All these characteristics for the beta rhythm were higher in experiments with both types of additional memory load as compared to those without the memory load.

  6. East Asian International Student Experiences as Learners of English as an Additional Language: Implications for School Counsellors

    ERIC Educational Resources Information Center

    Popadiuk, Natalee E.; Marshall, Steve

    2011-01-01

    In the school counselling literature, little focus is placed on international students who are learners of English as an Additional Language (EAL) and on school counselling support related to their language acquisition. Using the Critical Incident Technique, we analyzed transcripts of 21 international EAL students from China, Japan, and Korea who…

  7. The effects of the addition of a pediatric surgery fellow on the operative experience of the general surgery resident.

    PubMed

    Raines, Alexander; Garwe, Tabitha; Adeseye, Ademola; Ruiz-Elizalde, Alejandro; Churchill, Warren; Tuggle, David; Mantor, Cameron; Lees, Jason

    2015-06-01

    Adding fellows to surgical departments with residency programs can affect resident education. Our specific aim was to evaluate the effect of adding a pediatric surgery (PS) fellow on the number of index PS cases logged by the general surgery (GS) residents. At a single institution with both PS and GS programs, we examined the number of logged cases for the fellows and residents over 10 years [5 years before (Time 1) and 5 years after (Time 2) the addition of a PS fellow]. Additionally, the procedure related relative value units (RVUs) recorded by the faculty were evaluated. The fellows averaged 752 and 703 cases during Times 1 and 2, respectively, decreasing by 49 (P = 0.2303). The residents averaged 172 and 161 cases annually during Time 1 and Time 2, respectively, decreasing by 11 (P = 0.7340). The total number of procedure related RVUs was 4627 and 6000 during Times 1 and 2, respectively. The number of cases logged by the PS fellows and GS residents decreased after the addition of a PS fellow; however, the decrease was not significant. Programs can reasonably add an additional PS fellow, but care should be taken especially in programs that are otherwise static in size.

  8. High Resolution DNA Stable Isotope Probing Reveals that Root Exudate Addition to Soil Changes the Identity of the Microbes that Degrade Cellulose but not the Rate of Degradation

    NASA Astrophysics Data System (ADS)

    Campbell, A.; Pepe-Ranney, C. P.; Nguyen, A. V. T.; Buckley, D. H.

    2015-12-01

    Plant roots release compounds, such as root exudates, which can alter soil organic matter (SOM) decomposition and have large impacts on soil carbon (C) retention. The changes in SOM turnover resulting from the addition of organic and/or inorganic substrates are termed 'priming effects'. In this study we examine the effects of root exudates on the priming of cellulose added as particulate organic matter. We amended soil microcosms with 13C-cellulose in the presence or absence of artificial root exudate additions and incubated over time for 45 days. Soils receiving the root exudate (RE) were given either one large dose or multiple, small doses of RE. In each treatment we tracked operational taxonomic units (OTUs) assimilating 13C from cellulose (herein, known as a 'responder') over time using DNA stable isotope probing coupled with next generation sequencing. In all treatments the same amount of cellulose-13C was respired indicating the addition of RE did not result in the priming of cellulose decomposition. However, cellulose responders were different depending on treatment and time of sampling (days 14, 28 and 45). We identified a total of 10,361 OTUs, of which there were 369 cellulose responders in the cellulose only treatment, 273 in the repeated, small dose RE treatment, and 358 in the RE single, large dose treatment. Most of the cellulose responders found in all treatments belonged to phyla Bacteroidetes, Planctomycetes, Proteobacteria, Verrucomicrobia, and Chloroflexi. The response time of phyla varies; for instance, more OTUs in Bacteroidetes were observed on day 14 and diminish with each subsequent sampling time. On the other hand, OTUs in Verrucomicrobia increased in response over time. Our study shows no priming effect resulting from the addition of root exudates, although the identity of the microbial mediators of cellulose decomposition varies in each treatment.

  9. Analysis of sequences from field samples reveals the presence of the recently described pepper vein yellows virus (genus Polerovirus) in six additional countries.

    PubMed

    Knierim, Dennis; Tsai, Wen-Shi; Kenyon, Lawrence

    2013-06-01

    Polerovirus infection was detected by reverse transcription polymerase chain reaction (RT-PCR) in 29 pepper plants (Capsicum spp.) and one black nightshade plant (Solanum nigrum) sample collected from fields in India, Indonesia, Mali, Philippines, Thailand and Taiwan. At least two representative samples for each country were selected to generate a general polerovirus RT-PCR product of 1.4 kb length for sequencing. Sequence analysis of the partial genome sequences revealed the presence of pepper vein yellows virus (PeVYV) in all 13 samples. A 1990 Australian herbarium sample of pepper described by serological means as infected with capsicum yellows virus (CYV) was identified by sequence analysis of a partial CP sequence as probably infected with a potato leaf roll virus (PLRV) isolate.

  10. Effects of biochar addition on greenhouse gas emissions and microbial responses in a short-term laboratory experiment.

    PubMed

    Yoo, Gayoung; Kang, Hojeong

    2012-01-01

    Biochar application to soil has drawn much attention as a strategy to sequester atmospheric carbon in soil ecosystems. The applicability of this strategy as a climate change mitigation option is limited by our understanding of the mechanisms responsible for the observed changes in greenhouse gas emissions from soils, microbial responses, and soil fertility changes. We conducted an 8-wk laboratory incubation using soils from PASTURE (silt loam) and RICE PADDY (silt loam) sites with and without two types of biochar (biochar from swine manure [CHAR-M] and from barley stover [CHAR-B]). Responses to addition of the different biochars varied with the soil source. Addition of CHAR-B did not change CO and CH evolution from the PASTURE or the RICE PADDY soils, but there was a decrease in NO emissions from the PASTURE soil. The effects of CHAR-M addition on greenhouse gas emissions were different for the soils. The most substantial change was an increase in NO emissions from the RICE PADDY soil. This result was attributed to a combination of abundant denitrifiers in this soil and increased net nitrogen mineralization. Soil phosphatase and N-acetylglucosaminidase activity in the CHAR-B-treated soils was enhanced compared with the controls for both soils. Fungal biomass was higher in the CHAR-B-treated RICE PADDY soil. From our results, we suggest CHAR-B to be an appropriate amendment for the PASTURE and RICE PADDY soils because it provides increased nitrogen availability and microbial activity with no net increase in greenhouse gas emissions. Application of CHAR-M to RICE PADDY soils could result in excess nitrogen availability, which may increase NO emissions and possible NO leaching problems. Thus, this study confirms that the ability of environmentally sound biochar additions to sequester carbon in soils depends on the characteristics of the receiving soil as well as the nature of the biochar.

  11. Treatment with Tacrolimus and Sirolimus Reveals No Additional Adverse Effects on Human Islets In Vitro Compared to Each Drug Alone but They Are Reduced by Adding Glucocorticoids

    PubMed Central

    Kloster-Jensen, Kristine; Sahraoui, Afaf; Vethe, Nils Tore; Korsgren, Olle; Bergan, Stein; Foss, Aksel; Scholz, Hanne

    2016-01-01

    Tacrolimus and sirolimus are important immunosuppressive drugs used in human islet transplantation; however, they are linked to detrimental effects on islets and reduction of long-term graft function. Few studies investigate the direct effects of these drugs combined in parallel with single drug exposure. Human islets were treated with or without tacrolimus (30 μg/L), sirolimus (30 μg/L), or a combination thereof for 24 hrs. Islet function as well as apoptosis was assessed by glucose-stimulated insulin secretion (GSIS) and Cell Death ELISA. Proinflammatory cytokines were analysed by qRT-PCR and Bio-Plex. Islets exposed to the combination of sirolimus and tacrolimus were treated with or without methylprednisolone (1000 μg/L) and the expression of the proinflammatory cytokines was investigated. We found the following: (i) No additive reduction in function and viability in islets existed when tacrolimus and sirolimus were combined compared to the single drug. (ii) Increased expression of proinflammatory cytokines mRNA and protein levels in islets took place. (iii) Methylprednisolone significantly decreased the proinflammatory response in islets induced by the drug combination. Although human islets are prone to direct toxic effect of tacrolimus and sirolimus, we found no additive effects of the drug combination. Short-term exposure of glucocorticoids could effectively reduce the proinflammatory response in human islets induced by the combination of tacrolimus and sirolimus. PMID:26885529

  12. Tertiary structure of human alpha1-acid glycoprotein (orosomucoid). Straightforward fluorescence experiments revealing the presence of a binding pocket.

    PubMed

    Albani, Jihad R

    2004-02-25

    Binding of hemin to alpha1-acid glycoprotein has been investigated. Hemin binds to the hydrophobic pocket of hemoproteins. The fluorescent probe 2-(p-toluidino)-6-naphthalenesulfonate (TNS) binds to a hydrophobic domain in alpha1-acid glycoprotein with a dissociation constant equal to 60 microM. Addition of hemin to an alpha1-acid glycoprotein-TNS complex induces the displacement of TNS from its binding site. At saturation (1 hemin for 1 protein) all the TNS has been displaced from its binding site. The dissociation constant of hemin-alpha1-acid glycoprotein was found equal to 2 microM. Thus, TNS and hemin bind to the same hydrophobic site: the pocket of alpha1-acid glycoprotein. Energy-transfer studies performed between the Trp residues of alpha1-acid glycoprotein and hemin indicated that efficiency (E) of Trp fluorescence quenching was equal to 80% and the Förster distance, R0 at which the efficiency of energy transfer is 50% was calculated to be 26 A, revealing a very high energy transfer.

  13. High confidence proteomic analysis of yeast LDs identifies additional droplet proteins and reveals connections to dolichol synthesis and sterol acetylation[S

    PubMed Central

    Currie, Erin; Guo, Xiuling; Christiano, Romain; Chitraju, Chandramohan; Kory, Nora; Harrison, Kenneth; Haas, Joel; Walther, Tobias C.; Farese, Robert V.

    2014-01-01

    Accurate protein inventories are essential for understanding an organelle’s functions. The lipid droplet (LD) is a ubiquitous intracellular organelle with major functions in lipid storage and metabolism. LDs differ from other organelles because they are bounded by a surface monolayer, presenting unique features for protein targeting to LDs. Many proteins of varied functions have been found in purified LD fractions by proteomics. While these studies have become increasingly sensitive, it is often unclear which of the identified proteins are specific to LDs. Here we used protein correlation profiling to identify 35 proteins that specifically enrich with LD fractions of Saccharomyces cerevisiae. Of these candidates, 30 fluorophore-tagged proteins localize to LDs by microscopy, including six proteins, several with human orthologs linked to diseases, which we newly identify as LD proteins (Cab5, Rer2, Say1, Tsc10, YKL047W, and YPR147C). Two of these proteins, Say1, a sterol deacetylase, and Rer2, a cis-isoprenyl transferase, are enzymes involved in sterol and polyprenol metabolism, respectively, and we show their activities are present in LD fractions. Our results provide a highly specific list of yeast LD proteins and reveal that the vast majority of these proteins are involved in lipid metabolism. PMID:24868093

  14. A comparative study of ancient environmental DNA to pollen and macrofossils from lake sediments reveals taxonomic overlap and additional plant taxa

    NASA Astrophysics Data System (ADS)

    Pedersen, Mikkel Winther; Ginolhac, Aurélien; Orlando, Ludovic; Olsen, Jesper; Andersen, Kenneth; Holm, Jakob; Funder, Svend; Willerslev, Eske; Kjær, Kurt H.

    2013-09-01

    We use 2nd generation sequencing technology on sedimentary ancient DNA (sedaDNA) from a lake in South Greenland to reconstruct the local floristic history around a low-arctic lake and compare the results with those previously obtained from pollen and macrofossils in the same lake. Thirty-eight of thirty-nine samples from the core yielded putative DNA sequences. Using a multiple assignment strategy on the trnL g-h DNA barcode, consisting of two different phylogenetic and one sequence similarity assignment approaches, thirteen families of plants were identified, of which two (Scrophulariaceae and Asparagaceae) are absent from the pollen and macrofossil records. An age model for the sediment based on twelve radiocarbon dates establishes a chronology and shows that the lake record dates back to 10,650 cal yr BP. Our results suggest that sedaDNA analysis from lake sediments, although taxonomically less detailed than pollen and macrofossil analyses can be a complementary tool for establishing the composition of both terrestrial and aquatic local plant communities and a method for identifying additional taxa.

  15. Physiologically-Relevant Modes of Membrane Interactions by the Human Antimicrobial Peptide, LL-37, Revealed by SFG Experiments

    NASA Astrophysics Data System (ADS)

    Ding, Bei; Soblosky, Lauren; Nguyen, Khoi; Geng, Junqing; Yu, Xinglong; Ramamoorthy, Ayyalusamy; Chen, Zhan

    2013-05-01

    Antimicrobial peptides (AMPs) could become the next generation antibiotic compounds which can overcome bacterial resistance by disrupting cell membranes and it is essential to determine the factors underlying its mechanism of action. Although high-resolution NMR and other biological studies have provided valuable insights, it has been a major challenge to follow the AMP-membrane interactions at physiologically-relevant low peptide concentrations. In this study, we demonstrate a novel approach to overcome this major limitation by performing Sum Frequency Generation (SFG) vibrational spectroscopic experiments on lipid bilayers containing an AMP, LL-37. Our results demonstrate the power of SFG to study non-linear helical peptides and also infer that lipid-peptide interaction and the peptide orientation depend on the lipid membrane composition. The observed SFG signal changes capture the aggregating process of LL-37 on membrane. In addition, our SFG results on cholesterol-containing lipid bilayers indicate the inhibition effect of cholesterol on peptide-induced membrane permeation process.

  16. In vitro fertilization experiments using sockeye salmon reveal that bigger eggs are more fertilizable under sperm limitation.

    PubMed

    Macfarlane, Christopher P; Hoysak, Drew J; Liley, N Robin; Gage, Matthew J G

    2009-07-07

    Although theory and widespread evidence show that the evolution of egg size is driven primarily by offspring and maternal fitness demands, an additional explanation invokes sperm limitation as a selective force that could also influence egg size optima. Levitan proposed that constraints from gamete encounter in external fertilization environments could select for enlargement of ova to increase the physical size of the fertilization target. We test this theory using in vitro fertilization experiments in an externally fertilizing fish. Sockeye salmon (Onchorhyncus nerka) females show considerable between-individual variation in ovum size, and we explored the consequences of this natural variation for the fertilization success of individual eggs under conditions of sperm limitation. By engineering consistent conditions where in vitro fertilization rate was always intermediate, we were able to compare the sizes of fertilized and unfertilized eggs across 20 fertilization replicates. After controlling for any changes in volume through incubation, results showed that successfully fertilized eggs were significantly larger than the eggs that failed to achieve fertilization. Under conditions without sperm limitation, fertility was unaffected by egg size. Our findings therefore support Levitan's theory, demonstrating empirically that some element of egg size variation could be selected by fertilization demands under sperm limitation. However, further research on sperm limitation in natural spawnings is required to assess the selective importance of these results.

  17. Physiologically-Relevant Modes of Membrane Interactions by the Human Antimicrobial Peptide, LL-37, Revealed by SFG Experiments

    PubMed Central

    Ding, Bei; Soblosky, Lauren; Nguyen, Khoi; Geng, Junqing; Yu, Xinglong; Ramamoorthy, Ayyalusamy; Chen, Zhan

    2013-01-01

    Antimicrobial peptides (AMPs) could become the next generation antibiotic compounds which can overcome bacterial resistance by disrupting cell membranes and it is essential to determine the factors underlying its mechanism of action. Although high-resolution NMR and other biological studies have provided valuable insights, it has been a major challenge to follow the AMP-membrane interactions at physiologically-relevant low peptide concentrations. In this study, we demonstrate a novel approach to overcome this major limitation by performing Sum Frequency Generation (SFG) vibrational spectroscopic experiments on lipid bilayers containing an AMP, LL-37. Our results demonstrate the power of SFG to study non-linear helical peptides and also infer that lipid-peptide interaction and the peptide orientation depend on the lipid membrane composition. The observed SFG signal changes capture the aggregating process of LL-37 on membrane. In addition, our SFG results on cholesterol-containing lipid bilayers indicate the inhibition effect of cholesterol on peptide-induced membrane permeation process. PMID:23676762

  18. Biological and climatic controls on leaf litter decomposition across European forests and grasslands revealed by reciprocal litter transplantation experiments

    NASA Astrophysics Data System (ADS)

    Portillo-Estrada, M.; Pihlatie, M.; Korhonen, J. F. J.; Levula, J.; Frumau, A. K. F.; Ibrom, A.; Lembrechts, J. J.; Morillas, L.; Horváth, L.; Jones, S. K.; Niinemets, Ü.

    2015-11-01

    Projection of carbon and nitrogen cycles to future climates is associated with large uncertainties, in particular due to uncertainties how changes in climate alter soil turnover, including litter decomposition. In addition, future conditions are expected to result in changes in vegetation composition, and accordingly in litter type and quality, but it is unclear how such changes could potentially alter litter decomposition. Litter transplantation experiments were carried out across 6 European sites (4 forest and 2 grasslands) spanning a large geographical and climatic gradient (5.6-11.4 °C in annual temperature 511-878 mm in precipitation) to gain insight into biological (litter origin and type, soil type) and climatic controls on litter decomposition. The decomposition k rates were overall higher in warmer and wetter sites than in colder and drier sites, and positively correlated to the litter total specific leaf area. Also, litter N content increased as less litter mass remained and decay went further. Surprisingly, this study demonstrates that climatic controls on litter decomposition are quantitatively more important than species, litter origin and soil type. Cumulative climatic variables, precipitation and air temperature (ignoring days with air temperatures below 0 °C), were appropriate to predict the litter remaining mass during decomposition (Mr). And Mr and cumulative air temperature were found to be the best predictors for litter carbon and nitrogen remaining during decomposition. We concluded with an equation for predicting the decomposition k rate by using mean annual air temperature and litter total specific leaf area.

  19. Interactions among hydraulic conductivity distributions, subsurface topography, and transport thresholds revealed by a multitracer hillslope irrigation experiment

    DOE PAGES

    Jackson, C. Rhett; Du, Enhao; Klaus, Julian; ...

    2016-08-12

    Interactions among hydraulic conductivity distributions, subsurface topography, and lateral flow are poorly understood. We applied 407 mm of water and a suite of tracers over 51 h to a 12 by 16.5 m forested hillslope segment to determine interflow thresholds, preferential pathway pore velocities, large-scale conductivities, the time series of event water fractions, and the fate of dissolved nutrients. The 12% hillslope featured loamy sand A and E horizons overlying a sandy clay loam Bt at 1.25 m average depth. Interflow measured from two drains within an interception trench commenced after 131 and 208 mm of irrigation. Cumulative interflow equaledmore » 49% of applied water. Conservative tracer differences between the collection drains indicated differences in flow paths and storages within the plot. Event water fractions rose steadily throughout irrigation, peaking at 50% sixteen h after irrigation ceased. Data implied that tightly held water exchanged with event water throughout the experiment and a substantial portion of preevent water was released from the argillic layer. Surface-applied dye tracers bypassed the matrix, with peak concentrations measured shortly after flow commencement, indicating preferential network conductivities of 864–2240 mm/h, yet no macropore flow was observed. Near steady-state flow conditions indicated average conductivities of 460 mm/h and 2.5 mm/h for topsoils and the Bt horizon, respectively. Low ammonium and phosphorus concentrations in the interflow suggested rapid uptake or sorption, while higher nitrate concentrations suggested more conservative transport. Lastly, these results reveal how hydraulic conductivity variation and subsurface topographic complexity explain otherwise paradoxical solute and flow behaviors.« less

  20. Interactions among hydraulic conductivity distributions, subsurface topography, and transport thresholds revealed by a multitracer hillslope irrigation experiment

    SciTech Connect

    Jackson, C. Rhett; Du, Enhao; Klaus, Julian; Griffiths, Natalie A.; Bitew, Menberu; McDonnell, Jeffrey J.

    2016-08-12

    Interactions among hydraulic conductivity distributions, subsurface topography, and lateral flow are poorly understood. We applied 407 mm of water and a suite of tracers over 51 h to a 12 by 16.5 m forested hillslope segment to determine interflow thresholds, preferential pathway pore velocities, large-scale conductivities, the time series of event water fractions, and the fate of dissolved nutrients. The 12% hillslope featured loamy sand A and E horizons overlying a sandy clay loam Bt at 1.25 m average depth. Interflow measured from two drains within an interception trench commenced after 131 and 208 mm of irrigation. Cumulative interflow equaled 49% of applied water. Conservative tracer differences between the collection drains indicated differences in flow paths and storages within the plot. Event water fractions rose steadily throughout irrigation, peaking at 50% sixteen h after irrigation ceased. Data implied that tightly held water exchanged with event water throughout the experiment and a substantial portion of preevent water was released from the argillic layer. Surface-applied dye tracers bypassed the matrix, with peak concentrations measured shortly after flow commencement, indicating preferential network conductivities of 864–2240 mm/h, yet no macropore flow was observed. Near steady-state flow conditions indicated average conductivities of 460 mm/h and 2.5 mm/h for topsoils and the Bt horizon, respectively. Low ammonium and phosphorus concentrations in the interflow suggested rapid uptake or sorption, while higher nitrate concentrations suggested more conservative transport. Lastly, these results reveal how hydraulic conductivity variation and subsurface topographic complexity explain otherwise paradoxical solute and flow behaviors.

  1. Microstructural Stability of Nanocrystalline Copper through the Addition of Antimony Dopants at Grain Boundaries: Experiments and Molecular Dynamics Simulations

    SciTech Connect

    Rajgarhia, Rahul K.; Saxena, Ashok; Spearot, Douglas; Hartwig, Ted; More, Karren Leslie; Meyer III, Harry M; Kenik, Edward A

    2010-01-01

    Experiments and simulations show that the microstructural stability of nanocrystalline Cu can be improved by adding impurity atoms, such as Sb, which migrate to the grain boundaries. Cu100-xSbx alloys are cast in three compositions (Cu-0.0, 0.2 and 0.5 at.%Sb) and subsequently processed into nanocrystalline form by equal channel angular extrusion (ECAE). The presence of Sb atoms at the grain boundaries increases the recrystallization temperature to 400 C compared to 200 C for pure nanocrystalline Cu, which was verified by measurements of microhardness, ultimate tensile strength, grain size using TEM, and Auger electron spectroscopy. Molecular dynamics (MD) simulations were performed using a wider range of Sb compositions (0.0 to 1.0 at.%Sb) to study the underlying mechanisms associated with stability. MD simulations show that Sb atoms reduce excess grain boundary energy and that 0.2 and 0.5 at.%Sb is enough to stabilize the nanocrystalline Cu microstructure.

  2. An enhanced plant lipidomics method based on multiplexed liquid chromatography-mass spectrometry reveals additional insights into cold- and drought-induced membrane remodeling.

    PubMed

    Tarazona, Pablo; Feussner, Kirstin; Feussner, Ivo

    2015-11-01

    Within the lipidome of plants a few bulk molecular species hamper the detection of the rest, which are present at relatively low levels. In addition, low-abundance species are often masked by numerous isobaric interferences, such as those caused by isoelemental species and isotopologues. This scenario not only means that minor species are underrepresented, but also leads to potential misidentifications and limits the structural information gathered by lipidomics approaches. In order to overcome these limitations we have developed a multiplexed liquid chromatography-mass spectrometry lipidomics platform able to achieve an enhanced coverage of plant lipidomes. The platform is based on a single extraction step followed by a series of ultra-performance liquid chromatography separations. Post-column flow is then directed to both a triple quadrupole analyzer for targeted profiling and a time-of-flight analyzer for accurate mass analysis. As a proof of concept, plants were subjected to cold or drought, which are known to trigger widespread remodeling events in plant cell membranes. Analysis of the leaf lipidome yielded 393 molecular species within 23 different lipid classes. This enhanced coverage allowed us to identify lipid molecular species and even classes that are altered upon stress, allowing hypotheses on role of glycosylinositolphosphoceramides (GIPC), steryl glycosides (SG) and acylated steryl glycosides (ASG) in drought stress to be addressed and confirming the findings from numerous previous studies with a single, wide-ranging lipidomics approach. This extended our knowledge on membrane remodeling during the drought response, integrating sphingolipids and sterol lipids into the current glycerolipid-based model.

  3. The newer aspect of dexmedetomidine use in dentistry: As an additive to local anesthesia, initial experience, and review of literature

    PubMed Central

    Kumar, Prashant; Thepra, Manju; Bhagol, Amrish; Priya, Kannu; Singh, Virendra

    2016-01-01

    Introduction: Despite the availability of a wide variety of pharmacological agents in the field of anesthesia, there has always been a continuous search for newer local anesthetic agents with improved efficacy, potency, and better handling properties. Dexmedetomidine, a selective alpha-2 adrenergic receptor agonist, is an emerging agent for provision of additive local anesthetic effect if used with conventional local anesthetics, which can be implicated in dentistry for performing many minor oral surgical procedures. The present paper reports a pilot study comparing clinical efficacy and potency of this newer emerging drug in combination with lignocaine. Materials and Methods: Ten patients undergoing orthodontic extraction for correction of malocclusion and other dentofacial deformities requiring orthodontic treatment were locally infiltrated with 2% lignocaine plus dexmedetomidine 1μ/ml and 2% lignocaine plus adrenaline in 1:200,000 dilution at two different appointments. The onset of action, duration of action, and pain threshold were assessed. Results: Onset of action was found to be faster with longer duration of action with the newer drug dexmedetomidine and lignocaine combination when compared with combination of lignocaine and adrenaline. Conclusion: The study demonstrated that the combination of dexmedetomidine with lignocaine enhances the local anesthetic potency of lignocaine without significant systemic effects when locally injected into oral mucosa. PMID:28163484

  4. Forestry Impacts on Mercury Mobility, Methylation, and Bioaccumulation - A Field Experiment with Enriched Stable Mercury Isotope Additions

    NASA Astrophysics Data System (ADS)

    Mitchell, Carl; Haynes, Kristine; Mazur, Maxwell; Fidler, Nathan; Eckley, Chris; Kolka, Randy; Eggert, Susan; Sebestyen, Stephen

    2013-04-01

    Forest harvesting has clear impacts on terrestrial hydrology at least over the short term. Similar biogeochemical impacts, such as augmented mercury fluxes or downstream impacts on ecosystems are not as clear, and recent studies have not demonstrated consistent or predictable impacts across systems. To gain a better process understanding of mercury cycling in upland forest-lowland peatland ecosystems, we undertook a field-scale experiment at a study site in northern Minnesota (USA) where shallow subsurface hillslope runoff flows into an adjacent peatland ecosystem. Starting in 2009, three upland forest plots (< 1 hectare each) were delineated and hydrometric infrastructure such as runoff trenches, snow lysimeters, soil moisture probes, shallow piezometers, and throughfall gauges were installed in each plot. We added 14.2 to 16.7 μg/m2 of enriched mercury-200 and mercury-204 (as dilute mercuric nitrate) in the spring of 2011 and 2012, respectively, to distinguish between contemporary and legacy mercury and to provide some insight into the duration of contemporary mercury mobility in impacted terrestrial ecosystems. During the late winter of 2012, one of the study plots was clearcut and approximately 80% of slash was removed. We clearcut a second plot without slash removal, and left the third plot as a control. Throughout the study, we have monitored (including isotopes): mercury in runoff, soil-air gaseous Hg fluxes, methylation potentials in the adjacent peatland, and bioaccumulation into invertebrates inhabiting the adjacent peatland. Early results mostly indicate that slash removal actually lessens the impacts of clearcutting on mercury mobility (although forest harvesting in general does have a significant impact) and that forestry operations at this scale have little to no impact on methylation or bioaccumulation in downstream peatlands. Thus far, the greatest impact of slash removal in forest harvested systems is an increase in mercury evasion, likely as a

  5. Effect of pore size on bone ingrowth into porous titanium implants fabricated by additive manufacturing: An in vivo experiment.

    PubMed

    Taniguchi, Naoya; Fujibayashi, Shunsuke; Takemoto, Mitsuru; Sasaki, Kiyoyuki; Otsuki, Bungo; Nakamura, Takashi; Matsushita, Tomiharu; Kokubo, Tadashi; Matsuda, Shuichi

    2016-02-01

    Selective laser melting (SLM) is an additive manufacturing technique with the ability to produce metallic scaffolds with accurately controlled pore size, porosity, and interconnectivity for orthopedic applications. However, the optimal pore structure of porous titanium manufactured by SLM remains unclear. In this study, we evaluated the effect of pore size with constant porosity on in vivo bone ingrowth in rabbits into porous titanium implants manufactured by SLM. Three porous titanium implants (with an intended porosity of 65% and pore sizes of 300, 600, and 900μm, designated the P300, P600, and P900 implants, respectively) were manufactured by SLM. A diamond lattice was adapted as the basic structure. Their porous structures were evaluated and verified using microfocus X-ray computed tomography. Their bone-implant fixation ability was evaluated by their implantation as porous-surfaced titanium plates into the cortical bone of the rabbit tibia. Bone ingrowth was evaluated by their implantation as cylindrical porous titanium implants into the cancellous bone of the rabbit femur for 2, 4, and 8weeks. The average pore sizes of the P300, P600, and P900 implants were 309, 632, and 956μm, respectively. The P600 implant demonstrated a significantly higher fixation ability at 2weeks than the other implants. After 4weeks, all models had sufficiently high fixation ability in a detaching test. Bone ingrowth into the P300 implant was lower than into the other implants at 4weeks. Because of its appropriate mechanical strength, high fixation ability, and rapid bone ingrowth, our results indicate that the pore structure of the P600 implant is a suitable porous structure for orthopedic implants manufactured by SLM.

  6. Climatic controls on leaf litter decomposition across European forests and grasslands revealed by reciprocal litter transplantation experiments

    NASA Astrophysics Data System (ADS)

    Portillo-Estrada, Miguel; Pihlatie, Mari; Korhonen, Janne F. J.; Levula, Janne; Frumau, Arnoud K. F.; Ibrom, Andreas; Lembrechts, Jonas J.; Morillas, Lourdes; Horváth, László; Jones, Stephanie K.; Niinemets, Ülo

    2016-03-01

    Carbon (C) and nitrogen (N) cycling under future climate change is associated with large uncertainties in litter decomposition and the turnover of soil C and N. In addition, future conditions (especially altered precipitation regimes and warming) are expected to result in changes in vegetation composition, and accordingly in litter species and chemical composition, but it is unclear how such changes could potentially alter litter decomposition. Litter transplantation experiments were carried out across six European sites (four forests and two grasslands) spanning a large geographical and climatic gradient (5.6-11.4 °C in annual temperature 511-878 mm in precipitation) to gain insight into the climatic controls on litter decomposition as well as the effect of litter origin and species. The decomposition k rates were overall higher in warmer and wetter sites than in colder and drier sites, and positively correlated with the litter total specific leaf area. Also, litter N content increased as less litter mass remained and decay went further. Surprisingly, this study demonstrates that climatic controls on litter decomposition are quantitatively more important than species or site of origin. Cumulative climatic variables, precipitation, soil water content and air temperature (ignoring days with air temperatures below zero degrees Celsius), were appropriate to predict the litter remaining mass during decomposition (Mr). Mr and cumulative air temperature were found to be the best predictors for litter carbon and nitrogen remaining during the decomposition. Using mean annual air temperature, precipitation, soil water content and litter total specific leaf area as parameters we were able to predict the annual decomposition rate (k) accurately.

  7. A field reciprocal transplant experiment reveals asymmetric costs of migration between lake and river ecotypes of three-spined sticklebacks (Gasterosteus aculeatus).

    PubMed

    Kaufmann, Joshka; Lenz, Tobias L; Kalbe, Martin; Milinski, Manfred; Eizaguirre, Christophe

    2017-02-17

    Theory of local adaptation predicts that non-adapted migrants will suffer increased costs compared to local residents. Ultimately this process can result in the reduction of gene flow and culminate in speciation. Here, we experimentally investigated the relative fitness of migrants in foreign habitats, focusing on diverging lake and river ecotypes of three-spined sticklebacks. A reciprocal transplant experiment performed in the field revealed asymmetric costs of migration: while mortality of river fish was increased under lake conditions, lake migrants suffered from reduced growth relative to river residents. Selection against migrants thus involved different traits in each habitat but generally contributed to bidirectional reduction in gene flow. Focusing particularly on the parasitic environments, migrant fish differed from resident fish in the parasite community they harboured. This pattern correlated with both cellular phenotypes of innate immunity as well as with allelic variation at the genes of the major histocompatibility complex. In addition to showing the costs of migration in three-spined sticklebacks, this study highlights the role of asymmetric selection particularly from parasitism in genotype sorting and in the emergence of local adaptation. This article is protected by copyright. All rights reserved.

  8. Effect of volcano ash additions on nutrient concentrations, bloom dynamics and community metabolism in a short-term experiment in the NW Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Weinbauer, Markus

    2016-04-01

    Volcano ash deposition is now considered as an important source of inorganic bioavailable iron which can relieve Fe-limitation in the ocean. As volcano ash also releases PO4, a experiment was performed in the NW Mediterranean Sea to test whether volcano ash deposition can affect nutrient dynamics and bloom development in a P-limited system. In a 54h experiment, it was shown that the development of a phytoplankton bloom was not enhanced or even repressed by ash additions of 2 and 20 mg l-1, whereas higher ash concentrations (200 mg l-1) induced a phytoplankton bloom as indicated by elevated Chlorophyll-a levels. Concurrently, net community production (NCP) and gross primary production (GPP) were enhanced at T24h at the highest ash additions. The metabolic balance was roughly neutral at low or no ash additions, but shifted towards phototrophy at the highest ash additions. The data on inorganic nutrient development and release estimates from ash material assays suggest relieving of P-limitation concomitant with NO3 and silicate use from ash. The concentration of TEP increased with increasing ash levels. The abundances of the heterotrophic compartment (bacteria, viruses and ciliates) also indicated dose-dependent responses. Our data suggest that heterotrophs won the competition for inorganic nutrients at ash levels of 2 and 20 mg l-1, whereas phytoplankton won at levels of 200 mg l-1. Overall, our experiments point to a strong potential of volcano ash deposition as forcing factor for nutrient dynamics and the activity of microbial plankton in a P-limited system.

  9. Changes in water, carbon, and nitrogen fluxes with the addition of biochar to soils: lessons learned from laboratory and greenhouse experiments

    NASA Astrophysics Data System (ADS)

    Barnes, R. T.; Gallagher, M. E.; Masiello, C. A.; Liu, Z.; Dugan, B.; Rudgers, J. A.

    2011-12-01

    The addition of biochar to agricultural soils has the potential to provide a number of ecosystem services, ranging from carbon (C) sequestration to increased soil fertility and crop production. It is estimated that 0.5 to 0.9 Pg of C yr-1 can be sequestered through the addition of biochar to soils, significantly increasing the charcoal flux to the biosphere over natural inputs from fire (0.05 to 0.20 Pg C yr-1). There remain large uncertainties about biochar mobility within the environment, making it a challenge to assess the ecosystem residence time of biochar. We conducted laboratory and greenhouse experiments to understand how soil amendment with laboratory-produced biochar changes water, C, and nitrogen (N) fluxes from soils. We used column experiments to assess how biochar amendment to three types of soils (sand, organic, clay-rich) affected hydraulic conductivity and dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) fluxes. Results varied with soil type; biochar significantly decreased the hydraulic conductivity of the sand and organic soils by a factor of 10.6 and 2.7, respectively. While not statistically significant, biochar addition increased the hydraulic conductivity of the clay-rich soil by 50% on average. The addition of biochar significantly increased the DOC fluxes from the C-poor sand and clay soils while it significantly decreased the DOC flux from the organic-rich soil. In contrast, TDN fluxes decreased with biochar additions from all soil types, though the results were not statistically significant from the clay-rich soil. These laboratory experiments suggest that changes in the hydraulic conductivity of soil due to biochar amendments could play a significant role in understanding how biochar additions to agricultural fields will change watershed C and N dynamics. We additionally conducted a 28-day greenhouse experiment with sorghum plants using a three-way factorial treatment (water availability x biochar x mycorrhizae) to

  10. 3 Neutrino mass experiments fit a strange 3 + 3 model, but will KATRIN reveal the model's unique 3-part signature?

    NASA Astrophysics Data System (ADS)

    Ehrlich, R.

    2016-12-01

    Evidence is presented in support of an unconventional 3 + 3 model of the neutrino mass eigenstates with specific m2 > 0 and m2 < 0 masses. The two large m2 > 0 masses of the model were originally suggested based on a SN 1987A analysis, and they were further supported by several dark matter fits. The new evidence for one of the m2 > 0 mass values comes from an analysis of published data from the three most precise tritium β - decay experiments. The KATRIN experiment by virtue of a unique 3-part signature should either confirm or reject the model in its entirety.

  11. Response of aboveground biomass and diversity to nitrogen addition – a five-year experiment in semi-arid grassland of Inner Mongolia, China

    PubMed Central

    He, Kejian; Qi, Yu; Huang, Yongmei; Chen, Huiying; Sheng, Zhilu; Xu, Xia; Duan, Lei

    2016-01-01

    Understanding the response of the plant community to increasing nitrogen (N) deposition is helpful for improving pasture management in semi-arid areas. We implemented a 5-year N addition experiment in a Stipa krylovii steppe of Inner Mongolia, northern China. The aboveground biomass (AGB) and species richness were measured annually. Along with the N addition levels, the species richness declined significantly, and the species composition changed noticeably. However, the total AGB did not exhibit a noticeable increase. We found that compensatory effects of the AGB occurred not only between the grasses and the forbs but also among Gramineae species. The plant responses to N addition, from the community to species level, lessened in dry years compared to wet or normal years. The N addition intensified the reduction of community productivity in dry years. Our study indicated that the compensatory effects of the AGB among the species sustained the stability of grassland productivity. However, biodiversity loss resulting from increasing N deposition might lead the semi-arid grassland ecosystem to be unsustainable, especially in dry years. PMID:27573360

  12. Response of aboveground biomass and diversity to nitrogen addition – a five-year experiment in semi-arid grassland of Inner Mongolia, China

    NASA Astrophysics Data System (ADS)

    He, Kejian; Qi, Yu; Huang, Yongmei; Chen, Huiying; Sheng, Zhilu; Xu, Xia; Duan, Lei

    2016-08-01

    Understanding the response of the plant community to increasing nitrogen (N) deposition is helpful for improving pasture management in semi-arid areas. We implemented a 5-year N addition experiment in a Stipa krylovii steppe of Inner Mongolia, northern China. The aboveground biomass (AGB) and species richness were measured annually. Along with the N addition levels, the species richness declined significantly, and the species composition changed noticeably. However, the total AGB did not exhibit a noticeable increase. We found that compensatory effects of the AGB occurred not only between the grasses and the forbs but also among Gramineae species. The plant responses to N addition, from the community to species level, lessened in dry years compared to wet or normal years. The N addition intensified the reduction of community productivity in dry years. Our study indicated that the compensatory effects of the AGB among the species sustained the stability of grassland productivity. However, biodiversity loss resulting from increasing N deposition might lead the semi-arid grassland ecosystem to be unsustainable, especially in dry years.

  13. Direct comparison between genomic constitution and flavonoid contents in Allium multiple alien addition lines reveals chromosomal locations of genes related to biosynthesis from dihydrokaempferol to quercetin glucosides in scaly leaf of shallot (Allium cepa L.).

    PubMed

    Masuzaki, S; Shigyo, M; Yamauchi, N

    2006-02-01

    The extrachromosome 5A of shallot (Allium cepa L., genomes AA) has an important role in flavonoid biosynthesis in the scaly leaf of Allium fistulosum-shallot monosomic addition lines (FF+nA). This study deals with the production and biochemical characterisation of A. fistulosum-shallot multiple alien addition lines carrying at least 5A to determine the chromosomal locations of genes for quercetin formation. The multiple alien additions were selected from the crossing between allotriploid FFA (female symbol) and A. fistulosum (male symbol). The 113 plants obtained from this cross were analysed by a chromosome 5A-specific PGI isozyme marker of shallot. Thirty plants were preliminarily selected for an alien addition carrying 5A. The chromosome numbers of the 30 plants varied from 18 to 23. The other extrachromosomes in 19 plants were completely identified by using seven other chromosome markers of shallot. High-performance liquid chromatography analyses of the 19 multiple additions were conducted to identify the flavonoid compounds produced in the scaly leaves. Direct comparisons between the chromosomal constitution and the flavonoid contents of the multiple alien additions revealed that a flavonoid 3'-hydroxylase (F3'H) gene for the synthesis of quercetin from kaempferol was located on 7A and that an anonymous gene involved in the glucosidation of quercetin was on 3A or 4A. As a result of supplemental SCAR analyses by using genomic DNAs from two complete sets of A. fistulosum-shallot monosomic additions, we have assigned F3'H to 7A and flavonol synthase to 4A.

  14. Top-down mass spectrometry of intact membrane protein complexes reveals oligomeric state and sequence information in a single experiment

    PubMed Central

    Konijnenberg, Albert; Bannwarth, Ludovic; Yilmaz, Duygu; Koçer, Armağan; Venien-Bryan, Catherine; Sobott, Frank

    2015-01-01

    Here we study the intact stoichiometry and top-down fragmentation behavior of three integral membrane proteins which were natively reconstituted into detergent micelles: the mechano-sensitive ion channel of large conductance (MscL), the Kirbac potassium channel and the p7 viroporin from the hepatitis C virus. By releasing the proteins under nondenaturing conditions inside the mass spectrometer, we obtained their oligomeric sizes. Increasing the ion activation (collision energy) causes unfolding and subsequent ejection of a highly charged monomer from the membrane protein complexes. Further increase of the ion activation then causes collision-induced dissociation (CID) of the ejected monomers, with fragments observed which were predominantly found to stem from membrane-embedded regions. These experiments show how in a single experiment, we can probe the relation between higher-order structure and protein sequence, by combining the native MS data with fragmentation obtained from top-down MS. PMID:25970171

  15. Ecosystem experiment reveals benefits of natural and simulated beaver dams to a threatened population of steelhead (Oncorhynchus mykiss)

    PubMed Central

    Bouwes, Nicolaas; Weber, Nicholas; Jordan, Chris E.; Saunders, W. Carl; Tattam, Ian A.; Volk, Carol; Wheaton, Joseph M.; Pollock, Michael M.

    2016-01-01

    Beaver have been referred to as ecosystem engineers because of the large impacts their dam building activities have on the landscape; however, the benefits they may provide to fluvial fish species has been debated. We conducted a watershed-scale experiment to test how increasing beaver dam and colony persistence in a highly degraded incised stream affects the freshwater production of steelhead (Oncorhynchus mykiss). Following the installation of beaver dam analogs (BDAs), we observed significant increases in the density, survival, and production of juvenile steelhead without impacting upstream and downstream migrations. The steelhead response occurred as the quantity and complexity of their habitat increased. This study is the first large-scale experiment to quantify the benefits of beavers and BDAs to a fish population and its habitat. Beaver mediated restoration may be a viable and efficient strategy to recover ecosystem function of previously incised streams and to increase the production of imperiled fish populations. PMID:27373190

  16. Dissolved O2/Ar and other methods reveal rapid changes in productivity during a Lagrangian experiment in the Southern Ocean

    NASA Astrophysics Data System (ADS)

    Hamme, Roberta C.; Cassar, Nicolas; Lance, Veronica P.; Vaillancourt, Robert D.; Bender, Michael L.; Strutton, Peter G.; Moore, Tommy S.; Degrandpre, Michael D.; Sabine, Christopher L.; Ho, David T.; Hargreaves, Bruce R.

    2012-04-01

    We use continuous and discrete measurements of the dissolved O2/Ar ratio in the mixed layer to investigate the dynamics of biological productivity during the Southern Ocean Gas Exchange Experiment in March and April 2008. Injections of SF6 defined two water masses (patches) that were followed for up to 2 weeks. In the first patch, dissolved O2/Ar was supersaturated, indicating net biological production of organic carbon. In the second patch, rapidly decreasing O2/Ar could only be reasonably explained if the mixed layer was experiencing a period of net heterotrophy. The observations rule out dominant contributions from vertical mixing, lateral dilution, or respiration in the ship's underway seawater supply lines. We also compare nine different estimates of net community, new, primary, or gross production made during the experiment. Net community and new production estimates agreed well in the first patch but disagreed in the second patch, both during an initial net heterotrophic period but also during the apparently autotrophic period at the end of the observations. Rapidly changing productivity during the second patch complicated the comparison of methods that integrate over daily and several week timescales. Primary productivity values from on-deck 24 h 14C incubations and gross carbon production values from photosynthesis-irradiance experiments were nearly identical even during highly dynamic periods of net heterotrophy, while gross oxygen production measurements were 3.5-4.2 times higher but with uncertainties in that ratio near ±2. These comparisons show that the photosynthesis-irradiance experiments based on 1-2 h 14C incubations underestimated gross carbon production.

  17. Design of experiments reveals critical parameters for pilot-scale freeze-and-thaw processing of L-lactic dehydrogenase.

    PubMed

    Roessl, Ulrich; Humi, Sebastian; Leitgeb, Stefan; Nidetzky, Bernd

    2015-09-01

    Freezing constitutes an important unit operation of biotechnological protein production. Effects of freeze-and-thaw (F/T) process parameters on stability and other quality attributes of the protein product are usually not well understood. Here a design of experiments (DoE) approach was used to characterize the F/T behavior of L-lactic dehydrogenase (LDH) in a 700-mL pilot-scale freeze container equipped with internal temperature and pH probes. In 24-hour experiments, target temperature between -10 and -38°C most strongly affected LDH stability whereby enzyme activity was retained best at the highest temperature of -10°C. Cooling profile and liquid fill volume also had significant effects on LDH stability and affected the protein aggregation significantly. Parameters of the thawing phase had a comparably small effect on LDH stability. Experiments in which the standard sodium phosphate buffer was exchanged by Tris-HCl and the non-ionic surfactant Tween 80 was added to the protein solution showed that pH shift during freezing and protein surface exposure were the main factors responsible for LDH instability at the lower freeze temperatures. Collectively, evidence is presented that supports the use of DoE-based systematic analysis at pilot scale in the identification of F/T process parameters critical for protein stability and in the development of suitable process control strategies.

  18. Brain-based decoding of mentally imagined film clips and sounds reveals experience-based information patterns in film professionals.

    PubMed

    de Borst, Aline W; Valente, Giancarlo; Jääskeläinen, Iiro P; Tikka, Pia

    2016-04-01

    In the perceptual domain, it has been shown that the human brain is strongly shaped through experience, leading to expertise in highly-skilled professionals. What has remained unclear is whether specialization also shapes brain networks underlying mental imagery. In our fMRI study, we aimed to uncover modality-specific mental imagery specialization of film experts. Using multi-voxel pattern analysis we decoded from brain activity of professional cinematographers and sound designers whether they were imagining sounds or images of particular film clips. In each expert group distinct multi-voxel patterns, specific for the modality of their expertise, were found during classification of imagery modality. These patterns were mainly localized in the occipito-temporal and parietal cortex for cinematographers and in the auditory cortex for sound designers. We also found generalized patterns across perception and imagery that were distinct for the two expert groups: they involved frontal cortex for the cinematographers and temporal cortex for the sound designers. Notably, the mental representations of film clips and sounds of cinematographers contained information that went beyond modality-specificity. We were able to successfully decode the implicit presence of film genre from brain activity during mental imagery in cinematographers. The results extend existing neuroimaging literature on expertise into the domain of mental imagery and show that experience in visual versus auditory imagery can alter the representation of information in modality-specific association cortices.

  19. Accuracy of diagnostic heat and moisture budgets using SESAME-79 field data as revealed by observing system simulation experiments. [Severe Environmental Storm and Mesoscale Experiment

    NASA Technical Reports Server (NTRS)

    Kuo, Y.-H.; Anthes, R. A.

    1984-01-01

    Observing system simulation experiments are used to investigate the accuracy of diagnostic heat and moisture budgets which employ the AVE-SESAME 1979 data. The time-including, four-dimensional data set of a mesoscale model is used to simulate rawinsonde observations from AVE-SESAME 1979. The 5 C/day (heat budget) and 2 g/kg per day (moisture budget) magnitudes of error obtained indicate difficulties in the diagnosis of the heating rate in weak convective systems. The influences exerted by observational frequency, objective analysis, observational density, vertical interpolation, and observational errors on the budget are also studied, and it is found that the temporal and spatial resolution of the SESAME regional network is marginal for diagnosing convective effects on a horizontal time scale of 550 x 550 km.

  20. Apatite/Melt Partitioning Experiments Reveal Redox Sensitivity to Cr, V, Mn, Ni, Eu, W, Th, and U

    NASA Technical Reports Server (NTRS)

    Righter, K.; Yang, S.; Humayun, M.

    2016-01-01

    Apatite is a common mineral in terrestrial, planetary, and asteroidal materials. It is commonly used for geochronology (U-Pb), sensing volatiles (H, F, Cl, S), and can concentrate rare earth elements (REE) during magmatic fractionation and in general. Some recent studies have shown that some kinds of phosphate may fractionate Hf and W and that Mn may be redox sensitive. Experimental studies have focused on REE and other lithophile elements and at simplified or not specified oxygen fugacities. There is a dearth of partitioning data for chalcophile, siderophile and other elements between apatite and melt. Here we carry out several experiments at variable fO2 to study the partitioning of a broad range of trace elements. We compare to existing data and then focus on several elements that exhibit redox dependent partitioning behavior.

  1. The stream of experience when watching artistic movies. Dynamic aesthetic effects revealed by the Continuous Evaluation Procedure (CEP)

    PubMed Central

    Muth, Claudia; Raab, Marius H.; Carbon, Claus-Christian

    2015-01-01

    Research in perception and appreciation is often focused on snapshots, stills of experience. Static approaches allow for multidimensional assessment, but are unable to catch the crucial dynamics of affective and perceptual processes; for instance, aesthetic phenomena such as the “Aesthetic-Aha” (the increase in liking after the sudden detection of Gestalt), effects of expectation, or Berlyne's idea that “disorientation” with a “promise of success” elicits interest. We conducted empirical studies on indeterminate artistic movies depicting the evolution and metamorphosis of Gestalt and investigated (i) the effects of sudden perceptual insights on liking; that is, “Aesthetic Aha”-effects, (ii) the dynamics of interest before moments of insight, and (iii) the dynamics of complexity before and after moments of insight. Via the so-called Continuous Evaluation Procedure (CEP) enabling analogous evaluation in a continuous way, participants assessed the material on two aesthetic dimensions blockwise either in a gallery or a laboratory. The material's inherent dynamics were described via assessments of liking, interest, determinacy, and surprise along with a computational analysis on the variable complexity. We identified moments of insight as peaks in determinacy and surprise. Statistically significant changes in liking and interest demonstrated that: (i) insights increase liking, (ii) interest already increases 1500 ms before such moments of insight, supporting the idea that it is evoked by an expectation of understanding, and (iii) insights occur during increasing complexity. We propose a preliminary model of dynamics in liking and interest with regard to complexity and perceptual insight and discuss descriptions of participants' experiences of insight. Our results point to the importance of systematic analyses of dynamics in art perception and appreciation. PMID:25873907

  2. Energetic changes caused by antigenic module insertion in a virus-like particle revealed by experiment and molecular dynamics simulations.

    PubMed

    Zhang, Lin; Tang, Ronghong; Bai, Shu; Connors, Natalie K; Lua, Linda H L; Chuan, Yap P; Middelberg, Anton P J; Sun, Yan

    2014-01-01

    The success of recombinant virus-like particles (VLPs) for human papillomavirus and hepatitis B demonstrates the potential of VLPs as safe and efficacious vaccines. With new modular designs emerging, the effects of antigen module insertion on the self-assembly and structural integrity of VLPs should be clarified so as to better enabling improved design. Previous work has revealed insights into the molecular energetics of a VLP subunit, capsomere, comparing energetics within various solution conditions known to drive or inhibit self-assembly. In the present study, molecular dynamics (MD) simulations coupled with the molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) method were performed to examine the molecular interactions and energetics in a modular capsomere of a murine polyomavirus (MPV) VLP designed to protect against influenza. Insertion of an influenza antigenic module is found to lower the binding energy within the capsomere, and a more active state is observed in Assembly Buffer as compared with that in Stabilization Buffer, which has been experimentally validated through measurements using differential scanning calorimetry. Further in-depth analysis based on free-energy decomposition indicates that destabilized binding can be attributed to electrostatic interaction induced by the chosen antigen module. These results provide molecular insights into the conformational stability of capsomeres and their abilities to be exploited for antigen presentation, and are expected to be beneficial for the biomolecular engineering of VLP vaccines.

  3. Energetic Changes Caused by Antigenic Module Insertion in a Virus-Like Particle Revealed by Experiment and Molecular Dynamics Simulations

    PubMed Central

    Zhang, Lin; Tang, Ronghong; Bai, Shu; Connors, Natalie K.; Lua, Linda H. L.; Chuan, Yap P.; Middelberg, Anton P. J.; Sun, Yan

    2014-01-01

    The success of recombinant virus-like particles (VLPs) for human papillomavirus and hepatitis B demonstrates the potential of VLPs as safe and efficacious vaccines. With new modular designs emerging, the effects of antigen module insertion on the self-assembly and structural integrity of VLPs should be clarified so as to better enabling improved design. Previous work has revealed insights into the molecular energetics of a VLP subunit, capsomere, comparing energetics within various solution conditions known to drive or inhibit self-assembly. In the present study, molecular dynamics (MD) simulations coupled with the molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) method were performed to examine the molecular interactions and energetics in a modular capsomere of a murine polyomavirus (MPV) VLP designed to protect against influenza. Insertion of an influenza antigenic module is found to lower the binding energy within the capsomere, and a more active state is observed in Assembly Buffer as compared with that in Stabilization Buffer, which has been experimentally validated through measurements using differential scanning calorimetry. Further in-depth analysis based on free-energy decomposition indicates that destabilized binding can be attributed to electrostatic interaction induced by the chosen antigen module. These results provide molecular insights into the conformational stability of capsomeres and their abilities to be exploited for antigen presentation, and are expected to be beneficial for the biomolecular engineering of VLP vaccines. PMID:25215874

  4. Seismic reflection data imaging and interpretation from Braniewo2014 experiment using additional wide-angle refraction and reflection and well-logs data

    NASA Astrophysics Data System (ADS)

    Trzeciak, Maciej; Majdański, Mariusz; Białas, Sebastian; Gaczyński, Edward; Maksym, Andrzej

    2015-04-01

    Braniewo2014 reflection and refraction experiment was realized in cooperation between Polish Oil and Gas Company (PGNiG) and the Institute of Geophysics (IGF), Polish Academy of Sciences, near the locality of Braniewo in northern Poland. PGNiG realized a 20-km-long reflection profile, using vibroseis and dynamite shooting; the aim of the reflection survey was to characterise Silurian shale gas reservoir. IGF deployed 59 seismic stations along this profile and registered additional full-spread wide-angle refraction and reflection data, with offsets up to 12 km; maximum offsets from the seismic reflection survey was 3 km. To improve the velocity information two velocity logs from near deep boreholes were used. The main goal of the joint reflection-refraction interpretation was to find relations between velocity field from reflection velocity analysis and refraction tomography, and to build a velocity model which would be consistent for both, reflection and refraction, datasets. In this paper we present imaging results and velocity models from Braniewo2014 experiment and the methodology we used.

  5. 3D Numerical Experiments of Lithospheric Transtension Reveal Complex Crustal-Scale Flow and Strain Partitioning in Transdomes

    NASA Astrophysics Data System (ADS)

    Rey, P. F.; Mondy, L. S.; Duclaux, G.; Teyssier, C. P.; Whitney, D. L.

    2015-12-01

    We have used Underworld to perform a series of numerical experiments involving a 256 x 256 x 128 km domain, at a grid resolution of 1.33 km. The kinematic boundary conditions simulate a lithospheric-scale pull-apart setting. We compare the structural and thermal evolution of a model involving a crust of thickness 40 km (TMoho=540ºC) with a model with a crust of thickness 60 km (TMoho=830ºC). We show that in the thick, hot crust model the flow in the pull-apart region is strongly partitioned between the strong upper crust and the weak lower crust. The weak, deep crust flows toward the pull-apart region to isostatically compensate the stretching and thinning of the upper crust. In contrast, the velocity field in the upper crust remains parallel to the imposed direction of extension. In the pull-apart region a transdome, made of two parallel foliation folds (or sub-domes), forms. In the dome, fabrics evolve from strong vertical flattening in between the two sub-domes, to shallow dipping constriction roughly parallel to the direction of extension in the upper part of the transdome.

  6. Co-addition of manure increases the dissipation rates of tylosin A and the numbers of resistance genes in laboratory incubation experiments.

    PubMed

    Li, Qian; Wang, Yan; Zou, Yong-De; Liao, Xin-Di; Liang, Juan-Boo; Xin, Wen; Wu, Yin-Bao

    2015-09-15

    The behavior of veterinary antibiotics in the soil is commonly studied using the following methods to add antibiotics to the soil: (A) adding manure collected from animals fed a diet that includes antibiotics; (B) adding antibiotic-free animal manure spiked with antibiotics; and (C) the direct addition of antibiotics. However, most studies have only used methods (B) and (C) in their research, and few studies have simultaneously compared the different antibiotic addition methods. This study used tylosin A (TYLA) as a model antibiotic to compare the effects of these three commonly used antibiotic addition methods on the dissipation rates of TYLA and the numbers of resistance genes in laboratory incubation experiments. The results showed that the three treatment methods produced similar TYLA degradation trends; however, there were significant differences (P<0.05) in the TYLA degradation half-life (t1/2) among the three methods. The half-life of TYLA degradation in treatments A, B and C was 2.44 ± 0.04, 1.21 ± 0.03 and 5.13 ± 0.11 days, respectively. The presence of manure resulted in a higher electrical conductivity (EC), higher relative abundance of Citrobacter amalonaticus, higher macrolide resistant gene (ermB, ermF and ermT) count and lower ecological toxicity in the soil, which could partially explain the higher TYLA degradation rate in the treatments containing manure. The higher degradation rate of TYLA in treatment B when compared to treatment A could be due to the lower concentrations of tylosin B (TYLB) and tylosin D (TYLD). The main route for veterinary antibiotics to enter the soil is via the manure of animals that have been administered antibiotics. Therefore, the more appropriate method to study the degradation and ecotoxicity of antibiotic residues in the soil is by using manure from animals fed/administered the particular antibiotic rather than by adding the antibiotic directly to the soil.

  7. Reproductive isolation revealed in preliminary crossbreeding experiments using field collected Triatoma dimidiata (Hemiptera: Reduviidae) from three ITS–2 defined groups

    PubMed Central

    García, Mauricio; Menes, Marianela; Dorn, Patricia L.; Monroy, Carlota; Richards, Bethany; Panzera, Francisco; Bustamante, Dulce María

    2013-01-01

    Triatoma dimidiata, a Chagas disease vector distributed in Mexico, Central America, Colombia, Venezuela, Peru and Ecuador, has been studied using genetic markers and four groups have been defined by ITS–2 sequences: 1A, 1B, 2 and 3. To gather evidence on the divergence and reproductive isolation among T. dimidiata ITS–2 groups, we carried out 15 crossbreeding experiments with field–collected sylvan and domestic T. dimidiata from Guatemala where three groups are found: 1A, 2 and 3. Reciprocal crosses between individuals from groups 1A and 2, and a cross between group 2 individuals from different habitats, produced an average 129.78±42.29 eggs with hatching success ranging from 31.6% to 90.1%. The offspring of these crosses reached the adult stage, and crosses between F1 insects produced eggs. These results suggest that there are no pre– or post– zygotic reproductive barriers between groups 1A and 2, or within group 2. Crosses between group 3 females and males from groups 1A or 2 produced on average 85.67±30.26 eggs and none of them hatched. These results support the existence of pre– zygotic barriers between T. dimidiata group 3 and groups 1A and 2. The group 3 individuals were collected in sylvatic environments in Yaxha, Peten, Guatemala. Previously, distinct chromosomal characteristics (cytotype 3) were described in individuals from this population. Based on this evidence we suggest that this population is divergent at the species level from other T. dimidiata populations. PMID:24041592

  8. The evolutionary analysis on complement genes reveals that fishes C3 and C9 experience different evolutionary patterns.

    PubMed

    Wang, Shanchen; Wang, Rixin; Xu, Tianjun

    2013-12-01

    Complement is a humoral factor of innate immunity and plays an essential role in altering the host of the presence of potential pathogens and clearing of invading microorganisms. The third complement component (C3) not only is regarded as the crossing of the three pathways of complement activation, but also serves one of the bridges linking innate and acquired immunity. The nine complement component (C9) can combine with C5b, C6, C7 and C8 to form MAC which bounds to the surface of microorganisms to kill them. The evidence of evolution on C3 genes which have multiple functions and plays central role in innate immunity was documented in our previous study. Now we were interested in the evolution of C9 genes which were the terminal complement components. For these reasons, we want to explore the evolutionary patterns of C9 and whether C3 and C9 experience different evolutionary patterns. In our study, we used the sliding window method to separately calculate the values of ω among fishes and mammals of C3 and C9 codons. In order to detect the positive selection sites, we used the maximum likelihood (ML) method to study the evolutionary pattern on C3 and C9 genes. Positive selection sites were detected in mammalian C9 genes and no positive selection sites were detected in fishes C9 genes. However, no positive selection sites were detected in mammalian C3 genes and positive selection sites were detected in fishes C3 genes. The result indicated that C3 and C9 had different evolutionary patterns on mammals and fishes. In conclusion, different living environments lead to different evolutionary patterns on C3 and C9 in mammals and fishes. Besides, different complement components may have different evolutionary patterns on mammals and fishes.

  9. A landscape-scale field experiment reveals the importance of dispersal in a resource-limited metacommunity.

    PubMed

    Lancaster, Jill; Downes, Barbara J

    2017-02-01

    . Out of 54 common taxa, roughly half responded to the experiment; responders and non-responders had similar proportions of upstream specialists and of different functional feeding groups. Contrary to many non-experimental studies, our results demonstrate that extensive dispersal can be very important and, for many species, potentially more important than the abiotic environment or biotic constraints in affecting community structure when adequate resources are available.

  10. The preferential growth of branched GDGT source microorganisms under aerobic conditions in peat revealed by stable isotope probing experiments

    NASA Astrophysics Data System (ADS)

    Huguet, Arnaud; Meador, Travis B.; Laggoun-Défarge, Fatima; Könneke, Martin; Derenne, Sylvie; Hinrichs, Kai-Uwe

    2016-04-01

    , whereas corresponding rates in the anaerobic acrotelm incubations were more than an order of magnitude slower (< 3 ng cm-3 y-1). Production rates of bacterial fatty acids approached or exceeded 1 μg cm-3 y-1 in both aerobic and anaerobic incubations, and were therefore much higher than those of brGDGTs. This suggests that the brGDGT producers are a minor constituent of the microbial community in Sphagnum-dominated peatlands or brGDGTs are a small component of the microbial cell membrane in comparison to fatty acids, despite the typically high brGDGT concentrations observed in peat. In conclusion, our results reveal that brGDGT source microorganisms preferentially grow under oxic to sub-oxic conditions, likely as facultative anaerobes. We show for the first time that these microorganisms are especially active at the peat surface, in contrast to the deeper layers, implying that the high abundance of brGDGTs observed in the catotlem should result from the accumulation of the brGDGTs actively produced in the acrotelm. Reference Weijers, J.W.H., Wiesenberg, G.L.B., Bol, R., Hopmans, E.C., Pancost, R.D., 2010. Biogeosciences 7, 2959-2973.

  11. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  12. The Role of Patients’ Age on Their Preferences for Choosing Additional Blood Pressure-Lowering Drugs: A Discrete Choice Experiment in Patients with Diabetes

    PubMed Central

    de Vries, Sieta T.; de Vries, Folgerdiena M.; Dekker, Thijs; Haaijer-Ruskamp, Flora M.; de Zeeuw, Dick; Ranchor, Adelita V.; Denig, Petra

    2015-01-01

    Objectives To assess whether patients’ willingness to add a blood pressure-lowering drug and the importance they attach to specific treatment characteristics differ among age groups in patients with type 2 diabetes. Materials and Methods Patients being prescribed at least an oral glucose-lowering and a blood pressure-lowering drug completed a questionnaire including a discrete choice experiment. This experiment contained choice sets with hypothetical blood pressure-lowering drugs and a no additional drug alternative, which differed in their characteristics (i.e. effects and intake moments). Differences in willingness to add a drug were compared between patients <75 years (non-aged) and ≥75 years (aged) using Pearson χ2-tests. Multinomial logit models were used to assess and compare the importance attached to the characteristics. Results Of the 161 patients who completed the questionnaire, 151 (72%) could be included in the analyses (mean age 68 years; 42% female). Aged patients were less willing to add a drug than non-aged patients (67% versus 84% respectively; P = 0.017). In both age groups, the effect on blood pressure was most important for choosing a drug, followed by the risk of adverse drug events and the risk of death. The effect on limitations due to stroke was only significant in the non-aged group. The effect on blood pressure was slightly more important in the non-aged than the aged group (P = 0.043). Conclusions Aged patients appear less willing to add a preventive drug than non-aged patients. The importance attached to various treatment characteristics does not seem to differ much among age groups. PMID:26445349

  13. Influence of the penetration enhancer isopropyl myristate on stratum corneum lipid model membranes revealed by neutron diffraction and (2)H NMR experiments.

    PubMed

    Eichner, Adina; Stahlberg, Sören; Sonnenberger, Stefan; Lange, Stefan; Dobner, Bodo; Ostermann, Andreas; Schrader, Tobias E; Hauß, Thomas; Schroeter, Annett; Huster, Daniel; Neubert, Reinhard H H

    2017-05-01

    The stratum corneum (SC) provides the main barrier properties in native skin. The barrier function is attributed to the intercellular lipids, forming continuous multilamellar membranes. In this study, SC lipid membranes in model ratios were enriched with deuterated lipids in order to investigate structural and dynamical properties by neutron diffraction and (2)H solid-state NMR spectroscopy. Further, the effect of the penetration enhancer isopropyl myristate (IPM) on the structure of a well-known SC lipid model membrane containing synthetically derived methyl-branched ceramide [EOS], ceramide [AP], behenic acid and cholesterol (23/10/33/33wt%) was investigated. IPM supported the formation of a single short-periodicity phase (SPP), in which we determined the molecular organization of CER[AP] and CER[EOS]-br for the first time. Furthermore, the thermotropic phase behavior of the lipid system was analyzed by additional neutron diffraction studies as well as by (2)H solid-state NMR spectroscopy, covering temperatures of 32°C (physiological skin temperature), 50°C, and 70°C with a subsequent cooldown back to skin temperature. Both techniques revealed a phase transition and a hysteresis effect. During the cooldown, Bragg peaks corresponding to a long-periodicity phase (LPP) appeared. Additionally, (2)H NMR revealed that the IPM molecules are isotopic mobile at all temperatures.

  14. Seismic velocity structure and spatial distribution of reflection intensity off the Boso Peninsula, Central Japan, revealed by an ocean bottom seismographic experiment

    NASA Astrophysics Data System (ADS)

    Kono, Akihiro; Sato, Toshinori; Shinohara, Masanao; Mochizuki, Kimihiro; Yamada, Tomoaki; Uehira, Kenji; Shinbo, Takashi; Machida, Yuuya; Hino, Ryota; Azuma, Ryosuke

    2016-04-01

    Off the Boso Peninsula, central Japan, where the Sagami Trough is in the south and the Japan Trench is in the east, there is a triple junction where the Pacific plate (PAC), the Philippine Sea plate (PHS) and the Honshu island arc (HIA) meet each other. In this region, the PAC subducts beneath the PHS and the HIA, and the PHS subducts beneath the HIA. Due to the subduction of 2 oceanic plates, numerous seismic events took place in the past. In order to understand these events, it is important to image structure of these plates. Hence, many researchers attempted to reveal the substructure from natural earthquakes and seismic experiments. Because most of the seismometers are placed inland area and the regular seismicity off Boso is inactive, it is difficult to reveal the precise substructure off Boso area using only natural earthquakes. Although several marine seismic experiments using active sources were conducted, vast area remains unclear off Boso Peninsula. In order to improve the situation, a marine seismic experiment, using airgun as an active source, was conducted from 30th July to 4th of August, 2009. The survey line has 216 km length and 20 Ocean Bottom Seismometers (OBSs) were placed on it. We estimated 2-D P-wave velocity structure from the airgun data using the PMDM (Progressive Model Development Method; Sato and Kenett, 2000) and the FAST (First Arrival Seismic Tomography ; Zelt and Barton, 1998). Furthermore, we identified the probable reflection phases from the data and estimated the location of reflectors using Travel time mapping method (Fujie et al. 2006). We found some reflection phases from the data, and the reflectors are located near the region where P-wave velocity is 5.0 km/s. We interpret that the reflectors indicate the plate boundary between the PHS and the HIA. The variation of the intensity of reflection along the upper surface of PHS seems to be consistent with the result from previous reflection seismic experiment conducted by Kimura et

  15. Food additives

    MedlinePlus

    ... or natural. Natural food additives include: Herbs or spices to add flavor to foods Vinegar for pickling ... Certain colors improve the appearance of foods. Many spices, as well as natural and man-made flavors, ...

  16. An experiment on individual ‘parochial altruism’ revealing no connection between individual ‘altruism’ and individual ‘parochialism’

    PubMed Central

    Corr, Philip J.; Hargreaves Heap, Shaun P.; Seger, Charles R.; Tsutsui, Kei

    2015-01-01

    Is parochial altruism an attribute of individual behavior? This is the question we address with an experiment. We examine whether the individual pro-sociality that is revealed in the public goods and trust games when interacting with fellow group members helps predict individual parochialism, as measured by the in-group bias (i.e., the difference in these games in pro-sociality when interacting with own group members as compared with members of another group). We find that it is not. An examination of the Big-5 personality predictors of each behavior reinforces this result: they are different. In short, knowing how pro-social individuals are with respect to fellow group members does not help predict their parochialism. PMID:26347703

  17. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  18. Phosphazene additives

    DOEpatents

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  19. In situ formation of the first proteinogenically functionalized [TeW6O24O2(Glu)]7– structure reveals unprecedented chemical and geometrical features of the Anderson-type cluster† †Electronic supplementary information (ESI) available: Full experimental details and additional figures are provided. See DOI: 10.1039/c6cc07004c Click here for additional data file. Click here for additional data file. Click here for additional data file.

    PubMed Central

    Molitor, Christian; Bijelic, Aleksandar

    2016-01-01

    The chemistry of polyoxometalates (POMs) in a protein environment is an almost unexplored but highly relevant research field as important biological and pharmacological attributes of certain POMs are based on their interactions with proteins. We report on the A-type Anderson–Evans polyoxotungstate, [TeW6O24]6– (TEW), mediated crystallization of Coreopsis grandiflora aurone synthase (cgAUS1) using ∼0.24 mM protein and 1.0 mM TEW. The 1.78 Å crystal structure reveals the covalent binding of TEW to the protein under the formation of an unprecedented polyoxotungstate cluster, [TeW6O24O2(Glu)]7– (GluTEW). The polyoxotungstate–protein complex exhibits the first covalent bond between a protein and the A-type Anderson–Evans cluster, an archetype where up to now no hybrid structures exist. The polyoxotungstate is modified at two of its six addenda tungsten atoms, which covalently bind to the carboxylic oxygen atoms of glutamic acid (Glu157), leading to W–O distances of ∼2.35 Å. This ligand substitution reaction is accompanied by a reduction of the coordination number of two μ3 polyoxotungstate oxygen atoms. This is so far unique since all known hybridizations of the Anderson–Evans POM with organic units have been obtained via the functionalization of the B-type Anderson–Evans structure through its bridging oxygen atoms. The structure reported here proves the reactivity of this POM archetype's addenda atoms as it has been administered into the protein solution as a pre-assembled cluster. Moreover, the novel cluster [TeW6O24O2(Glu)]7– displays the great versatility of the Anderson–Evans POM class. PMID:27722437

  20. "Invisible" conformers of an antifungal disulfide protein revealed by constrained cold and heat unfolding, CEST-NMR experiments, and molecular dynamics calculations.

    PubMed

    Fizil, Ádám; Gáspári, Zoltán; Barna, Terézia; Marx, Florentine; Batta, Gyula

    2015-03-23

    Transition between conformational states in proteins is being recognized as a possible key factor of function. In support of this, hidden dynamic NMR structures were detected in several cases up to populations of a few percent. Here, we show by two- and three-state analysis of thermal unfolding, that the population of hidden states may weight 20-40 % at 298 K in a disulfide-rich protein. In addition, sensitive (15) N-CEST NMR experiments identified a low populated (0.15 %) state that was in slow exchange with the folded PAF protein. Remarkably, other techniques failed to identify the rest of the NMR "dark matter". Comparison of the temperature dependence of chemical shifts from experiments and molecular dynamics calculations suggests that hidden conformers of PAF differ in the loop and terminal regions and are most similar in the evolutionary conserved core. Our observations point to the existence of a complex conformational landscape with multiple conformational states in dynamic equilibrium, with diverse exchange rates presumably responsible for the completely hidden nature of a considerable fraction.

  1. Improving planning, design, reporting and scientific quality of animal experiments by using the Gold Standard Publication Checklist, in addition to the ARRIVE guidelines.

    PubMed

    Hooijmans, Carlijn R; de Vries, Rob; Leenaars, Marlies; Curfs, Jo; Ritskes-Hoitinga, Merel

    2011-03-01

    Several studies have demonstrated serious omissions in the way research that use animals is reported. In order to improve the quality of reporting of animal experiments, the Animals in research: reporting in vivo experiments (ARRIVE) Guidelines were published in the British Journal of Pharmacology in August 2010. However, not only the quality of reporting of completed animal studies needs to be improved, but also the design and execution of new experiments. With both these goals in mind, we published the Gold Standard Publication Checklist (GSPC) in May 2010, a few months before the ARRIVE guidelines appeared. In this letter, we compare the GSPC checklist with the ARRIVE Guidelines. The GSPC describes certain items in more detail, which makes it both easier to use when designing and conducting an experiment and particularly suitable for making systematic reviews of animal studies more feasible. In order to improve not only the reporting but also the planning, design, execution and thereby, the scientific quality of animal experiments, we strongly recommend to all scientists involved in animal experimentation and to editors of journals publishing animal studies to take a closer look at the contents of both the ARRIVE guidelines and GSPC, and select the set of guidelines which is most appropriate for their particular situation.

  2. Irradiation of Metallic Fuels with Rare Earth Additions for Actinide Transmutation in the ATR. Experiment Description for AFC-2A and AFC-2B

    SciTech Connect

    S. L. Hayes; D. J. Utterbeck; T. A. Hyde

    2007-03-01

    The U.S. Advanced Fuel Cycle Initiative (AFCI), now within the broader context of the Global Nuclear Energy Partnership (GNEP), seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposal and the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository. One important component of the technology development is actinide-bearing metallic transmutation fuel forms containing plutonium, neptunium, americium (and possibly curium) isotopes. The proposed AFC-2A and AFC-2B irradiation experiments are a continuation of the metallic fuel test series in progress in the ATR. This report documents the experiment description and test matrix of the proposed experiments and the Post Irradiation Examination (PIE) and fabrication schedule.

  3. Irradiation of Metallic Fuels with Rare Earth Additions for Actinide Transmutation in the Advanced Test Reactor. Experiment Description for AFC-2A and AFC-2B

    SciTech Connect

    Hayes, Steven L.

    2006-12-01

    The U.S. Advanced Fuel Cycle Initiative (AFCI), now within the broader context of the Global Nuclear Energy Partnership (GNEP), seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposal and the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository. One important component of the technology development is actinide-bearing metallic transmutation fuel forms containing plutonium, neptunium, americium (and possibly curium) isotopes. The proposed AFC-2A and AFC-2B irradiation experiments are a continuation of the metallic fuel test series in progress in the ATR. This report documents the experiment description and test matrix of the proposed experiments and the Post Irradiation Examination (PIE) and fabrication schedule.

  4. Irradiation of Metallic Fuels with Rare Earth Additions for Actinide Transmutation in the ATR. Experiment Description for AFC-2A and AFC-2B

    SciTech Connect

    S. L. Hayes; D. J. Utterbeck; T. A. Hyde

    2006-11-01

    The U.S. Advanced Fuel Cycle Initiative (AFCI), now within the broader context of the Global Nuclear Energy Partnership (GNEP), seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposal and the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository. One important component of the technology development is actinide-bearing metallic transmutation fuel forms containing plutonium, neptunium, americium (and possibly curium) isotopes. The proposed AFC-2A and AFC-2B irradiation experiments are a continuation of the metallic fuel test series in progress in the ATR. This report documents the experiment description and test matrix of the proposed experiments and the Post Irradiation Examination (PIE) and fabrication schedule.

  5. Qualitative impact of salinity, UV radiation and turbulence on leaching of organic plastic additives from four common plastics - A lab experiment.

    PubMed

    Suhrhoff, Tim Jesper; Scholz-Böttcher, Barbara M

    2016-01-15

    Four common consumer plastic samples (polyethylene, polystyrene, polyethylene terephthalate, polyvinylchloride) were studied to investigate the impact of physical parameters such as turbulence, salinity and UV irradiance on leaching behavior of selected plastic components. Polymers were exposed to two different salinities (i.e. 0 and 35 g/kg), UV radiation and turbulence. Additives (e.g. bisphenol A, phthalates, citrates, and Irgafos® 168 phosphate) and oligomers were detected in initial plastics and aqueous extracts. Identification and quantification was performed by GC-FID/MS. Bisphenol A and citrate based additives are leached easier compared to phthalates. The print highly contributed to the chemical burden of the analyzed polyethylene bag. The study underlines a positive relationship between turbulence and magnitude of leaching. Salinity had a minor impact that differs for each analyte. Global annual release of additives from assessed plastics into marine environments is estimated to be between 35 and 917 tons, of which most are derived from plasticized polyvinylchloride.

  6. Generation, Isolation, and Characterization of a Stable Enol from Grignard Addition to a Bis-Ester: A Microscale Experiment for the Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Nicaise, Olivier J. C.; Ostrom, Kyle F.; Dalke, Brent J.

    2005-01-01

    An experiment is described that introduces students to the concept of temperature-dependent stability of the tetrahedral intermediate in an acyl-transfer reaction. The process involves the determination of the structure of an alpha-ketoester and its corresponding remarkably stable enol ester to suggest a mechanism for the formation of the products.

  7. Detection of Salicylic Acid in Willow Bark: An Addition to a Classic Series of Experiments in the Introductory Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Clay, Matthew D.; McLeod, Eric J.

    2012-01-01

    Salicylic acid and its derivative, acetylsalicylic acid, are often encountered in introductory organic chemistry experiments, and mention is often made that salicylic acid was originally isolated from the bark of the willow tree. This biological connection, however, is typically not further pursued, leaving students with an impression that biology…

  8. Marker-Based Estimates Reveal Significant Non-additive Effects in Clonally Propagated Cassava (Manihot esculenta): Implications for the Prediction of Total Genetic Value and the Selection of Varieties.

    PubMed

    Wolfe, Marnin D; Kulakow, Peter; Rabbi, Ismail Y; Jannink, Jean-Luc

    2016-08-31

    In clonally propagated crops, non-additive genetic effects can be effectively exploited by the identification of superior genetic individuals as varieties. Cassava (Manihot esculenta Crantz) is a clonally propagated staple food crop that feeds hundreds of millions. We quantified the amount and nature of non-additive genetic variation for three key traits in a breeding population of cassava from sub-Saharan Africa using additive and non-additive genome-wide marker-based relationship matrices. We then assessed the accuracy of genomic prediction for total (additive plus non-additive) genetic value. We confirmed previous findings based on diallel populations, that non-additive genetic variation is significant for key cassava traits. Specifically, we found that dominance is particularly important for root yield and epistasis contributes strongly to variation in CMD resistance. Further, we showed that total genetic value predicted observed phenotypes more accurately than additive only models for root yield but not for dry matter content, which is mostly additive or for CMD resistance, which has high narrow-sense heritability. We address the implication of these results for cassava breeding and put our work in the context of previous results in cassava, and other plant and animal species.

  9. Micron-Size Zero-Valent Iron Emplacement in Porous Media Using Polymer Additives: Column and Flow Cell Ex-periments

    SciTech Connect

    Oostrom, Mart; Wietsma, Thomas W.; Covert, Matthew A.; Vermeul, Vince R.

    2006-03-20

    At the Hanford Site, an extensive In Situ Redox Manipulation (ISRM) permeable reactive barrier was installed to prevent chromate from reaching the Columbia River. However, chromium has been detected in several wells, indicating a premature loss of the reductive capacity in the aquifer. Laboratory experiments have been conducted to investigate whether barrier reductive capacity can be enhanced by adding micron-scale zero-valent iron to the high-permeability zones within the aquifer using shear-thinning fluids containing polymers. Porous media were packed in a wedge-shaped flow cell to create either a heterogeneous layered system with a high-permeability zone between two low-permeability zones or a high-permeability channel sur-rounded by low-permeability materials. The injection flow rate, polymer type, polymer concentration, and injected pore volumes were determined based on preliminary short- and long-column experiments. The flow cell experiments indicated that iron concentration enhancements of at least 0.6% (w/w) could be obtained using moderate flow rates and injection of 30 pore volumes. The 0.6% amended Fe0 concentration would provide approximately 20 times the average reductive capacity that is provided by the dithionite-reduced iron in the ISRM barrier. Calculations show that a 1-m-long Fe0 amended zone with an average concentration of 0.6% w/w iron subject to a groundwater velocity of 1 m/day will have an estimated longevity of 7.2 years.

  10. Competitive hydration and dehydration at olivine-quartz boundary revealed by hydrothermal experiments: Implications for silica metasomatism at the crust-mantle boundary

    NASA Astrophysics Data System (ADS)

    Oyanagi, Ryosuke; Okamoto, Atsushi; Hirano, Nobuo; Tsuchiya, Noriyoshi

    2015-09-01

    Serpentinization occurs via interactions between mantle peridotite and water that commonly passes through the crust. Given that such a fluid has a high silica activity compared with mantle peridotite, it is thought that serpentinization and silica metasomatism occur simultaneously at the crust-mantle boundary. In this study, we conducted hydrothermal experiments in the olivine (Ol)-quartz (Qtz)-H2O system at 250 °C and vapor-saturated pressure under highly alkaline conditions (NaOHaq, pH = 13.8 at 25 °C) to clarify the mechanism of silica metasomatism at the crust-mantle boundary. Composite powders consisting of a Qtz layer and an Ol layer were set in tube-in-tube vessels. After the experiments, the extents of serpentinization and metasomatic reactions were evaluated as a function of distance from the Ol-Qtz boundary. The mineralogy of the reaction products in the Ol-hosted region changed with increasing distance from the Ol-Qtz boundary, from smectite + serpentine (Smc zone) to serpentine + brucite + magnetite (Brc zone). Olivine hydration proceeded in both zones, but the total H2O content in the products was greater in the Brc zone than in the Smc zone. Mass balance calculations revealed that olivine hydration occurred without any supply of silica in the brucite zone. In contrast, the Smc zone was formed by silica metasomatism via competitive hydration and dehydration reactions. In the Smc zone, smectite formed via the simultaneous progress of olivine hydration and serpentine dehydration, and around the boundary of the Smc and Brc zones, serpentine formation occurred by olivine hydration and brucite dehydration. The relative extent of hydration and dehydration reactions controlled the along-tube variation in the rate of H2O production/consumption and the rate of volume increase. Our findings suggest that the competitive progress of serpentinization and silica metasomatic reactions would cause fluctuations in pore fluid pressure, possibly affecting the

  11. Spatio-Temporal Variation in Contrasting Effects of Resident Vegetation on Establishment, Growth and Reproduction of Dry Grassland Plants: Implications for Seed Addition Experiments

    PubMed Central

    Knappová, Jana; Knapp, Michal; Münzbergová, Zuzana

    2013-01-01

    Successful establishment of plants is limited by both biotic and abiotic conditions and their interactions. Seedling establishment is also used as a direct measure of habitat suitability, but transient changes in vegetation might provide windows of opportunity allowing plant species to colonize sites which otherwise appear unsuitable. We aimed to study spatio-temporal variability in the effects of resident vegetation on establishment, growth and reproduction of dry grassland species in abandoned arable fields representing potentially suitable habitats. Seeds were sown in disturbed (bare of vegetation and roots) and undisturbed plots in three fields abandoned in the last 20 years. To assess the effects of temporal variation on plant establishment, we initiated our experiments in two years (2007 and 2008). Seventeen out of the 35 sown species flowered within two years after sowing, while three species completely failed to become established. The vegetation in the undisturbed plots facilitated seedling establishment only in the year with low spring precipitation, and the effect did not hold for all species. In contrast, growth and flowering rate were consistently much greater in the disturbed plots, but the effect size differed between the fields and years of sowing. We show that colonization is more successful when site opening by disturbance coincide with other suitable conditions such as weather or soil characteristics. Seasonal variability involved in our study emphasizes the necessity of temporal replication of sowing experiments. Studies assessing habitat suitability by seed sowing should either involve both vegetation removal treatments and untreated plots or follow the gradient of vegetation cover. We strongly recommend following the numbers of established individuals, their sizes and reproductive success when assessing habitat suitability by seed sowing since one can gain completely different results in different phases of plant life cycle. PMID:23755288

  12. Structural and spectroscopic (UV-Vis, IR, Raman, and NMR) characteristics of anisaldehydes that are flavoring food additives: A density functional study in comparison with experiments

    NASA Astrophysics Data System (ADS)

    Altun, Ahmet; Swesi, O. A. A.; Alhatab, B. S. S.

    2017-01-01

    The molecular structures, vibrational spectra (IR and Raman), electronic spectra (UV-Vis and DOS), and NMR spectra (13C and 1H) of p-anisaldehyde, m-anisaldehyde, and o-anisaldehyde have been studied by using the B3LYP density functional and the 6-311++G** basis set. While p-anisaldehyde has been found to contain two stable conformers at room temperature, m-anisaldehyde and o-anisaldehyde contain four stable conformers. In agreement with the calculated ground-state energetics and small transition barriers, the comparison of the experimental and calculated spectra of the anisaldehydes indicates equilibrium between all conformers at room temperature. However, the two conformers of o-anisaldehyde, in which the methoxy group lies out of the ring plane, are too rare at the equilibrium. The equilibrium conditions of the conformers of the anisaldehyde isomers have been shown readily accessible through UV-Vis and 13C NMR spectral studies but requiring very detailed vibrational analyses. The effect of the solvent has been found to red-shift the electronic absorption bands and to make the anisaldehydes more reactive and soft. Molecular electrostatic potential maps of the anisaldehydes show that their oxygen atoms are the sites for nucleophilic reactivity. Compared with the most sophisticated NBO method, ESP charges have been found mostly reliable while Mulliken charges fail badly with the present large 6-311++G** basis set. The present calculations reproduce not only the experimental spectral characteristics of the anisaldehydes but also reveal their several structural features.

  13. Seismic Absorption and Modulus Measurements in Porous Rocks in Lab and Field: Physical, Chemical, and Biological Effects of Fluids (Detecting a Biosurfactant Additive in a Field Irrigation Experiment)

    SciTech Connect

    Spetzler, Hartmut

    2006-05-01

    We have been exploring a new technology that is based on using low-frequency seismic attenuation data to monitor changes in fluid saturation conditions in two-fluid phase porous materials. The seismic attenuation mechanism is related to the loss of energy due to the hysteresis of resistance to meniscus movement (changes in surface tension, wettability) when a pore containing two fluids is stressed at very low frequencies (< 10 Hz). This technology has potential applications to monitoring changes in (1) leakage at buried waste sites, (2) contaminant remediation, and (3) flooding during enhanced petroleum recovery. We have concluded a three year field study at the Maricopa Agricultural Center site of the University of Arizona. Three sets of instruments were installed along an East-West line perpendicular to the 50m by 50m inigation site. Each set of instruments consisted of one three component seismometer and one tiltmeter. Microseisms and solid Earth-tides served as strain sources. The former have a power peak at a period of about 6 seconds and the tides have about two cycles per day. Installation of instruments commenced in late summer of 2002. The instruments operated nearly continuously until April 2005. During the fall of 2003 the site was irrigated with water and one year later with water containing 150 ppm of a biosurfactant additive. This biodegradable additive served to mimic a class of contaminants that change the surface tension of the inigation fluid. Tilt data clearly show tidal tilts superimposed on local tilts due to agricultural irrigation and field work. When the observed signals were correlated with site specific theoretical tilt signals we saw no anomalies for the water irrigation in 2003, but large anomalies on two stations for the surfactant irrigation in 2004. Occasional failures of seismometers as well as data acquisition systems contributed to less than continuous coverage. These data are noisier than the tilt data, but do also show possible

  14. Influence of roots and mycorrhiza on the internal nitrogen cycle in an organic forest soil ­revealed by a 15N tracing experiment

    NASA Astrophysics Data System (ADS)

    Holz, M.; Rutting, T.; Klemedtsson, L.; Kuzyakov, Y.

    2014-12-01

    The cycle of nitrogen in soil is complex, consisting of many simultaneous occurring transformation processes. So far, microorganisms have been thought to govern N cycling in soil. Nevertheless, plant roots and their associated mycorrhizal symbionts may exert control on N turnover for example by input of labile C to soil. However, studies investigating the effect of roots on gross N turnover rates are scarce. We conducted a 15N tracer study under field conditions to reveal the effect of plants on soil N cycle. The experiment includes three treatments: (a) control, (b) excluding roots and (c) excluding roots + mycorrhiza. On the study site, exclusion of roots + mycorrhiza has previously been shown to increase N2O emissions which indicate that plants affect internal N cycling. 15NH4NO3 and NH415NO3 were given to the soil and traced for a period of 10 days. Gross N turnover rates were determined applying a numerical 15N tracing model. Results on N turnover rates showed that roots and their fungal symbionts increased N cycling probably by input of labile C to soil which may results in an activation of the microbial biomass. While gross N mineralization increased by 270 and 313 % compared to the treatment excluding roots + mycorrhiza, NH4+ immobilization increased by 402 and 489 %. Differences in ammonium and nitrate immobilization further indicated that ammonium was the preferred N source for roots and microorganisms. While ammonium availability decreased with trenching (0.59 compared to -0.47 and -0.96 μg N g-1 d-1), the opposite was true for nitrate (0.50 compared to 2.08 and 2.18 μg N g-1 d-1), explaining the increased N2O emissions which were likely caused by denitrification. Further, plants increased dissimilarity nitrate reduction to ammonium (DNRA) and affected autotrophic nitrification probably by the release of nitrification inhibitors and by influencing ammonium availability. We conclude that plants and their mycorrhizal symbionts actively control N cycling

  15. Rice Yield and the Fate of Fertilizer Nitrogen as Affected by Addition of Earthworm Casts Collected from Oilseed Rape Fields: A Pot Experiment

    PubMed Central

    Huang, Min; Zhou, Xuefeng; Xie, Xiaobing; Zhao, Chunrong; Chen, Jiana; Cao, Fangbo; Zou, Yingbin

    2016-01-01

    The mechanism associated with improvement of soil nutritional status by oilseed rape crop, leading to better performance of rice crop, in rice-oilseed rape cropping systems is little known. The present study was aimed to test the hypothesis that earthworm casts produced during oilseed rape-growing season have positive effects on grain yield and fertilizer nitrogen (N) utilization in the subsequent flooded rice crop. A 15N-tracing pot experiment was conducted to determine the effects of earthworm casts collected from oilseed rape fields on yield attributes in rice and the fate of fertilizer N. Soil treated with earthworm casts (soil: earthworm casts = 4: 1, w/w) (EC1) produced 39% higher grain yield than soil only (EC0). EC1 had 18% more panicle number and 10% higher spikelet filling percentage than EC0. Aboveground biomass and harvest index were higher in EC1 than in EC0 by 20% and 15%, respectively. SPAD values in flag leaves were 10% and 22% higher under EC1 than EC0 at 15 and 20 days after heading, respectively. EC1 had 19% higher total N uptake and 18% higher physiological N-use efficiency than EC0. These positive effects of earthworm casts on yield attributes offset negative effects of decreasing N rate from 0.74 g pot–1 (equivalent to the recommended field rate of 150 kg ha–1) to 0.44 g pot–1 (equivalent to 60% of the recommended rate). Fertilizer N retention rate was 7% higher while fertilizer N loss rate was 6% lower in EC1 than in EC0. Our study suggests that earthworm casts produced during oilseed rape-growing season are expected to have the following benefits on the subsequent flooded rice system: (1) improving growth and physiological processes in rice plants and consequently increasing rice grain yield, and (2) increasing fertilizer N retention rate and hence decreasing fertilizer N loss rate and reducing environmental risk. PMID:27880837

  16. Control of nitrification/denitrification in an onsite two-chamber intermittently aerated membrane bioreactor with alkalinity and carbon addition: Model and experiment.

    PubMed

    Perera, Mahamalage Kusumitha; Englehardt, James D; Tchobanoglous, George; Shamskhorzani, Reza

    2017-02-20

    Denitrifying membrane bioreactors (MBRs) are being found useful in water reuse treatment systems, including net-zero water (nearly closed-loop), non-reverse osmosis-based, direct potable reuse (DPR) systems. In such systems nitrogen may need to be controlled in the MBR to meet the nitrate drinking water standard in the finished water. To achieve efficient nitrification and denitrification, the addition of alkalinity and external carbon may be required, and control of the carbon feed rate is then important. In this work, an onsite, two-chamber aerobic nitrifying/denitrifying MBR, representing one unit process of a net-zero water, non-reverse osmosis-based DPR system, was modeled as a basis for control of the MBR internal recycling rate, aeration rate, and external carbon feed rate. Specifically, a modification of the activated sludge model ASM2dSMP was modified further to represent the rate of recycling between separate aerobic and anoxic chambers, rates of carbon and alkalinity feed, and variable aeration schedule, and was demonstrated versus field data. The optimal aeration pattern for the modeled reactor configuration and influent matrix was found to be 30 min of aeration in a 2 h cycle (104 m(3) air/d per 1 m(3)/d average influent), to ultimately meet the nitrate drinking water standard. Optimal recycling ratios (inter-chamber flow to average daily flow) were found to be 1.5 and 3 during rest and mixing periods, respectively. The model can be used to optimize aeration pattern and recycling ratio in such MBRs, with slight modifications to reflect reactor configuration, influent matrix, and target nitrogen species concentrations, though some recalibration may be required.

  17. Molecular characterization of Trichomonas gallinae isolates recovered from the Canadian Maritime provinces' wild avifauna reveals the presence of the genotype responsible for the European finch trichomonosis epidemic and additional strains.

    PubMed

    McBurney, Scott; Kelly-Clark, Whitney K; Forzán, María J; Lawson, Becki; Tyler, Kevin M; Greenwood, Spencer J

    2015-07-01

    Finch trichomonosis, caused by Trichomonas gallinae, emerged in the Canadian Maritime provinces in 2007 and has since caused ongoing mortality in regional purple finch (Carpodacus purpureus) and American goldfinch (Carduelis tristis) populations. Trichomonas gallinae was isolated from (1) finches and rock pigeons (Columbia livia) submitted for post-mortem or live-captured at bird feeding sites experiencing trichomonosis mortality; (2) bird seed at these same sites; and (3) rock pigeons live-captured at known roosts or humanely killed. Isolates were characterized using internal transcribed spacer (ITS) region and iron hydrogenase (Fe-hyd) gene sequences. Two distinct ITS types were found. Type A was identical to the UK finch epidemic strain and was isolated from finches and a rock pigeon with trichomonosis; apparently healthy rock pigeons and finches; and bird seed at an outbreak site. Type B was obtained from apparently healthy rock pigeons. Fe-hyd sequencing revealed six distinct subtypes. The predominant subtype in both finches and the rock pigeon with trichomonosis was identical to the UK finch epidemic strain A1. Single nucleotide polymorphisms in Fe-hyd sequences suggest there is fine-scale variation amongst isolates and that finch trichomonosis emergence in this region may not have been caused by a single spill-over event.

  18. Origins of enigmatic C-3 methyl and C-3 H porphyrins in ancient sediments revealed from formation of pyrophaeophorbide d in simulation experiments

    NASA Astrophysics Data System (ADS)

    Pickering, Matthew D.; Keely, Brendan J.

    2013-03-01

    The reaction of methyl pyrophaeophorbide a with hydrogen sulfide and oxygen under mild conditions (low temperature, moderate pH), which resemble those in certain natural environments, leads to its near quantitative conversion into methyl pyrophaeophorbide d (82-89%). The transformation, via oxidative cleavage of the C-3 vinyl substituent of pyrophaeophorbide a to afford an aldehyde at C-3, results from co-oxidation of the vinyl group and hydrogen sulfide by molecular oxygen. The co-oxidation transformation pathway operating on vinyl substituted chlorophyll derivatives can explain the origins of C-3 methyl and C-3 H porphyrins in ancient sediments and oils, structures for which the origins were previously unresolved. Evaluation of previous reports of C-3 methyl and C-3 H porphyrins in ancient sediments and oils reveals that their distributions are consistent with insights provided from analysis of the reaction mechanisms revealed by the laboratory studies. Thus, the sedimentary distributions reveal key features of the depositional settings, in particular the presence of a deep or a shallow chemocline. The oxidative cleavage of the C-3 vinyl group also provides insight into the biosynthesis of chlorophyll d by the cyanobacterium Acaryochloris marina, and offers a mild alternative to classical methods for the synthetic manipulation of the vinyl substituents of tetrapyrroles.

  19. The Classroom Experiences of Pupils with Special Educational Needs in Mainstream Primary Schools--1976 to 2012. What Do Data from Systematic Observation Studies Reveal about Pupils' Educational Experiences over Time?

    ERIC Educational Resources Information Center

    Webster, Rob

    2015-01-01

    This paper presents results of an analysis of primary-aged pupils' educational experiences over a 35 year period. Data drawn from a set of large-scale systematic observation studies, conducted in the UK between 1976 and 2012, are used to describe pupils' average classroom experiences at six points in time over this period. These data are then used…

  20. Group Sparse Additive Models

    PubMed Central

    Yin, Junming; Chen, Xi; Xing, Eric P.

    2016-01-01

    We consider the problem of sparse variable selection in nonparametric additive models, with the prior knowledge of the structure among the covariates to encourage those variables within a group to be selected jointly. Previous works either study the group sparsity in the parametric setting (e.g., group lasso), or address the problem in the nonparametric setting without exploiting the structural information (e.g., sparse additive models). In this paper, we present a new method, called group sparse additive models (GroupSpAM), which can handle group sparsity in additive models. We generalize the ℓ1/ℓ2 norm to Hilbert spaces as the sparsity-inducing penalty in GroupSpAM. Moreover, we derive a novel thresholding condition for identifying the functional sparsity at the group level, and propose an efficient block coordinate descent algorithm for constructing the estimate. We demonstrate by simulation that GroupSpAM substantially outperforms the competing methods in terms of support recovery and prediction accuracy in additive models, and also conduct a comparative experiment on a real breast cancer dataset.

  1. How Are Preferences Revealed?

    PubMed Central

    Beshears, John; Choi, James J.; Laibson, David; Madrian, Brigitte C.

    2009-01-01

    Revealed preferences are tastes that rationalize an economic agent’s observed actions. Normative preferences represent the agent’s actual interests. It sometimes makes sense to assume that revealed preferences are identical to normative preferences. But there are many cases where this assumption is violated. We identify five factors that increase the likelihood of a disparity between revealed preferences and normative preferences: passive choice, complexity, limited personal experience, third-party marketing, and intertemporal choice. We then discuss six approaches that jointly contribute to the identification of normative preferences: structural estimation, active decisions, asymptotic choice, aggregated revealed preferences, reported preferences, and informed preferences. Each of these approaches uses consumer behavior to infer some property of normative preferences without equating revealed and normative preferences. We illustrate these issues with evidence from savings and investment outcomes. PMID:24761048

  2. The complex folding behavior of HIV-1-protease monomer revealed by optical-tweezer single-molecule experiments and molecular dynamics simulations.

    PubMed

    Caldarini, M; Sonar, P; Valpapuram, I; Tavella, D; Volonté, C; Pandini, V; Vanoni, M A; Aliverti, A; Broglia, R A; Tiana, G; Cecconi, C

    2014-12-01

    We have used optical tweezers and molecular dynamics simulations to investigate the unfolding and refolding process of a stable monomeric form of HIV-1-protease (PR). We have characterized the behavior under tension of the native state (N), and that of the ensemble of partially folded (PF) conformations the protein visits en route to N, which collectively act as a long-lived state controlling the slow kinetic phase of the folding process. Our results reveal a rich network of unfolding events, where the native state unfolds either in a two-state manner or by populating an intermediate state I, while the PF state unravels through a multitude of pathways, underscoring its structural heterogeneity. Refolding of mechanically denatured HIV-1-PR monomers is also a multiple-pathway process. Molecular dynamics simulations allowed us to gain insight into possible conformations the protein adopts along the unfolding pathways, and provide information regarding possible structural features of the PF state.

  3. Intermittently-visual Tracking Experiments Reveal the Roles of Error-correction and Predictive Mechanisms in the Human Visual-motor Control System

    NASA Astrophysics Data System (ADS)

    Hayashi, Yoshikatsu; Tamura, Yurie; Sase, Kazuya; Sugawara, Ken; Sawada, Yasuji

    Prediction mechanism is necessary for human visual motion to compensate a delay of sensory-motor system. In a previous study, “proactive control” was discussed as one example of predictive function of human beings, in which motion of hands preceded the virtual moving target in visual tracking experiments. To study the roles of the positional-error correction mechanism and the prediction mechanism, we carried out an intermittently-visual tracking experiment where a circular orbit is segmented into the target-visible regions and the target-invisible regions. Main results found in this research were following. A rhythmic component appeared in the tracer velocity when the target velocity was relatively high. The period of the rhythm in the brain obtained from environmental stimuli is shortened more than 10%. The shortening of the period of rhythm in the brain accelerates the hand motion as soon as the visual information is cut-off, and causes the precedence of hand motion to the target motion. Although the precedence of the hand in the blind region is reset by the environmental information when the target enters the visible region, the hand motion precedes the target in average when the predictive mechanism dominates the error-corrective mechanism.

  4. Various Arsenic Network Structures in 112-Type Ca1-xLaxFe1-yPdyAs2 Revealed by Synchrotron X-ray Diffraction Experiments.

    PubMed

    Tamura, Shinya; Katayama, Naoyuki; Yamada, Yuto; Sugiyama, Yuki; Sugawara, Kento; Sawa, Hiroshi

    2017-03-06

    Two novel 112-type palladium-doped iron arsenides were synthesized and identified using comprehensive studies involving synchrotron X-ray diffraction and X-ray absorption near-edge structure (XANES) experiments. Whereas in-plane arsenic zigzag chains were found in the 112-type superconducting iron arsenide Ca1-xLaxFeAs2 with maximum Tc = 34 K, deformed arsenic network structures appeared in other 112-type materials, such as longitudinal arsenic zigzag chains in CaFe1-yPdyAs2 (y ∼ 0.51) and arsenic square sheets constructed via hypervalent bonding in Ca1-xLaxFe1-yPdyAs2 (x ∼ 0.31, y ∼ 0.30). As K-edge XANES spectra clarified the similar oxidization states around FeAs4 tetrahedrons, alluding to possible parents for high-Tc 112-type iron arsenide superconductors.

  5. Aspirin revealed

    NASA Astrophysics Data System (ADS)

    Lacey, D.; Hu, X. K.; Loboda, A. V.; Mosey, N. J.; Lipson, R. H.

    2007-03-01

    Experiments are described where the experimental conditions have been optimized to detect aspirin by MALDI mass spectrometry. Although protonated aspirin was not observed by MALDI, sodium and potassium aspirin adducts could be found. Significantly better signals could be obtained by using Rb and Cs salts as cationization sources. Quantum calculations were carried out to determine the structure and energetics of the Li, K, Rb, and Cs alkali--aspirin adducts.

  6. Trophic relationships on a fucoid shore in south-western Iceland as revealed by stable isotope analyses, laboratory experiments, field observations and gut analyses

    NASA Astrophysics Data System (ADS)

    Steinarsdóttir, M. B.; Ingólfsson, A.; Ólafsson, E.

    2009-04-01

    Rocky shores in the North Atlantic are known for their zonation patterns of both algae and animals, which can be expected to greatly affect food availability to consumers at different height levels on the shore. We tested the hypothesis that consumers would feed on the most abundant suitable food source in their surroundings. In total 36 species/taxa of common primary producers and consumers were sampled for stable isotope analyses from a sheltered fucoid shore at Hvassahraun in south-western Iceland. A selection of these species was also collected seasonally and from different height levels. Feeding experiments, field observations and gut analyses were also conducted. Our results were in good overall agreement with pre-existing knowledge of trophic relationships in the rocky intertidal. Consumers often appeared to be assimilating carbon and nitrogen from the most common diet in their immediate surroundings. The predator Nucella lapillus was thus feeding on different prey at different height levels in accordance with different densities of prey species. When tested in the laboratory, individuals taken from low on the shore would ignore the gastropod Littorina obtusata, uncommon at that height level, even when starved, while individuals from mid-shore readily ate the gastropod. This indicated that some kind of learned behaviour was involved. There were, however, important exceptions, most noteworthy the relatively small contribution to herbivores, both slow moving (the gastropod L. obtusata) and fast moving (the isopod Idotea granulosa and the amphipod Gammarus obtusatus) of the dominant alga at this site, Ascophyllum nodosum. The recent colonizer Fucus serratus seemed to be favoured. Selective feeding was indicated both by isotope signatures as well as by results of feeding experiments. Seasonal migrations of both slow and fast moving species could partly explain patterns observed.

  7. Revealing Ligand Binding Sites and Quantifying Subunit Variants of Noncovalent Protein Complexes in a Single Native Top-Down FTICR MS Experiment

    NASA Astrophysics Data System (ADS)

    Li, Huilin; Wongkongkathep, Piriya; Van Orden, Steve L.; Ogorzalek Loo, Rachel R.; Loo, Joseph A.

    2014-12-01

    "Native" mass spectrometry (MS) has been proven to be increasingly useful for structural biology studies of macromolecular assemblies. Using horse liver alcohol dehydrogenase (hADH) and yeast alcohol dehydrogenase (yADH) as examples, we demonstrate that rich information can be obtained in a single native top-down MS experiment using Fourier transform ion cyclotron mass spectrometry (FTICR MS). Beyond measuring the molecular weights of the protein complexes, isotopic mass resolution was achieved for yeast ADH tetramer (147 kDa) with an average resolving power of 412,700 at m/z 5466 in absorption mode, and the mass reflects that each subunit binds to two zinc atoms. The N-terminal 89 amino acid residues were sequenced in a top-down electron capture dissociation (ECD) experiment, along with the identifications of the zinc binding site at Cys46 and a point mutation (V58T). With the combination of various activation/dissociation techniques, including ECD, in-source dissociation (ISD), collisionally activated dissociation (CAD), and infrared multiphoton dissociation (IRMPD), 40% of the yADH sequence was derived directly from the native tetramer complex. For hADH, native top-down ECD-MS shows that both E and S subunits are present in the hADH sample, with a relative ratio of 4:1. Native top-down ISD of the hADH dimer shows that each subunit (E and S chains) binds not only to two zinc atoms, but also the NAD/NADH ligand, with a higher NAD/NADH binding preference for the S chain relative to the E chain. In total, 32% sequence coverage was achieved for both E and S chains.

  8. Arc visualization of odor objects reveals experience-dependent ensemble sharpening, separation, and merging in anterior piriform cortex in adult rat.

    PubMed

    Shakhawat, Amin Md; Harley, Carolyn W; Yuan, Qi

    2014-07-30

    Visualization using the immediate early gene Arc revealed sparser and more robust odor representations in the anterior piriform cortex of adult rats when odor was associated with water reward over 2-3 d. Rewarded odor "mixtures" resulted in rats responding to either component odor similarly, and, correspondingly, the odor representations became more similar as indexed by increased overlap in piriform Arc-expressing (Arc(+)) pyramidal neurons. The increased overlap was consistent with the rats' generalization from component odors. Discriminating among highly similar odor mixtures for reward led to increased differentiation of the neural representations as indexed by a reduction in overlap for piriform Arc(+) pyramidal neurons after training. Similar odor mixture discrimination also required more trials to criterion. The visible reduction in the overlap of odor representations indexes pattern separation. The Arc visualization of odor representations in the anterior piriform network suggests that odor objects are widely distributed representations and can be rapidly modified by reward training in adult rats. We suggest that dynamic changes such as those observed here in piriform odor encoding are at the heart of perceptual learning and reflect the continuing plastic nature of mature associative cortex as an outcome of successful problem solving.

  9. The Glycan Role in the Glycopeptide Immunogenicity Revealed by Atomistic Simulations and Spectroscopic Experiments on the Multiple Sclerosis Biomarker CSF114(Glc)

    NASA Astrophysics Data System (ADS)

    Bruno, Agostino; Scrima, Mario; Novellino, Ettore; D'Errico, Gerardino; D'Ursi, Anna Maria; Limongelli, Vittorio

    2015-03-01

    Glycoproteins are often recognized as not-self molecules by antibodies triggering the onset of severe autoimmune diseases such as Multiple Sclerosis (MS). Thus, the development of antigen-mimicking biomarkers represents an attractive strategy for an early diagnosis of the disease. An example is the synthetic glycopeptide CSF114(Glc), which was designed and tested as MS biomarker and whose clinical application was limited by its reduced ability to detect autoantibodies in MS patients. In the attempt to improve the efficacy of CSF114(Glc), we have characterized all the events leading to the final binding of the biomarker to the autoantibody using atomistic simulations, ESR and NMR experiments. The glycosydic moiety plays a primary role in the whole process. In particular, in an environment mimicking that used in the clinical tests the glycopeptide assumes a α-helix structure that is functional for the interaction with the antibody. In this conformation CSF114(Glc) binds the monoclonal antibody mAb8-18C5 similarly to the myelin oligodendrocyte glycoprotein MOG, which is a known MS auto-antigen, thus explaining its diagnostic activity. Our study offers new molecular bases to design more effective biomarkers and provides a most valid protocol to investigate other systems where the environment effect is determinant for the biological activity.

  10. Magnetic fluctuations in n-type high-Tc superconductors reveal breakdown of fermiology:Experiments and Fermi-liquid/RPA calculations

    SciTech Connect

    Krueger, S.D.

    2010-03-02

    By combining experimental measurements of the quasiparticle and dynamical magnetic properties of optimally electron-doped Pr{sub 0.88}LaCe{sub 0.12}CuO{sub 4} with theoretical calculations, we demonstrate that the conventional fermiology approach cannot possibly account for the magnetic fluctuations in these materials. In particular, we perform tunneling experiments on the very same sample for which a dynamical magnetic resonance has been reported recently and use photoemission data by others on a similar sample to characterize the fermionic quasiparticle excitations in great detail. We subsequently use this information to calculate the magnetic response within the conventional fermiology framework as applied in a large body of work for the hole-doped superconductors to find a profound disagreement between the theoretical expectations and the measurements: this approach predicts a steplike feature rather than a sharp resonance peak, it underestimates the intensity of the resonance by an order of magnitude, it suggests an unreasonable temperature dependence of the resonance, and most severely, it predicts that most of the spectral weight resides in incommensurate wings which are a key feature of the hole-doped cuprates but have never been observed in the electron-doped counterparts. Our findings strongly suggest that the magnetic fluctuations reflect the quantum-mechanical competition between antiferromagnetic and superconducting orders.

  11. Common-garden experiments reveal geographical variation in the interaction among Crotalaria pallida (Leguminosae: Papilionideae), Utetheisa ornatrix L. (Lepidoptera: Arctiidae), and extrafloral nectary visiting ants.

    PubMed

    Franco, M S; Cogni, R

    2013-06-01

    The study of geographical variation is a key approach to understand evolution of ecological interactions. We investigated geographical variation in the interaction among Crotalaria pallida (Leguminosae: Papilionideae), its specialized herbivore, Utetheisa ornatrix L. (Lepidoptera: Arctiidae), and ants attracted to extrafloral nectaries (EFNs). First, we used common-garden experiments with plants collected in different sites at different geographical scales to test for differences among populations in C. pallida attractiveness to ants. When we compared three populations from Southeast Brazil (150 km apart), the number of visiting ants per plant, and the percent of termite baits attacked by ants, were significantly different among plant populations. In a comparison of populations from SE Brazil and Florida (USA), there was no significant difference between the populations in the number of ants per plant or the frequency of baits attacked. Second, we tested in a common garden if U. ornatrix larvae present any behavior to avoid ant predation, and if there were genetic differences among populations. We observed that most larvae moved away from the vicinity of the EFNs (flowers and fruits) to the plant leaves. Of the larvae that moved to leaves, only 10% were attacked by ants while 89% of larvae that stayed near the fruit/flower were attacked. There was a significant difference among populations in the frequency of larvae that moved to the leaves and the frequency of larvae attacked by ants. We discuss the possible causes of the geographical differences observed and propose future research directions in this system.

  12. The Glycan Role in the Glycopeptide Immunogenicity Revealed by Atomistic Simulations and Spectroscopic Experiments on the Multiple Sclerosis Biomarker CSF114(Glc)

    PubMed Central

    Bruno, Agostino; Scrima, Mario; Novellino, Ettore; D'Errico, Gerardino; D'Ursi, Anna Maria; Limongelli, Vittorio

    2015-01-01

    Glycoproteins are often recognized as not-self molecules by antibodies triggering the onset of severe autoimmune diseases such as Multiple Sclerosis (MS). Thus, the development of antigen-mimicking biomarkers represents an attractive strategy for an early diagnosis of the disease. An example is the synthetic glycopeptide CSF114(Glc), which was designed and tested as MS biomarker and whose clinical application was limited by its reduced ability to detect autoantibodies in MS patients. In the attempt to improve the efficacy of CSF114(Glc), we have characterized all the events leading to the final binding of the biomarker to the autoantibody using atomistic simulations, ESR and NMR experiments. The glycosydic moiety plays a primary role in the whole process. In particular, in an environment mimicking that used in the clinical tests the glycopeptide assumes a α-helix structure that is functional for the interaction with the antibody. In this conformation CSF114(Glc) binds the monoclonal antibody mAb8-18C5 similarly to the myelin oligodendrocyte glycoprotein MOG, which is a known MS auto-antigen, thus explaining its diagnostic activity. Our study offers new molecular bases to design more effective biomarkers and provides a most valid protocol to investigate other systems where the environment effect is determinant for the biological activity. PMID:25776265

  13. Color Addition and Subtraction Apps

    ERIC Educational Resources Information Center

    Ruiz, Frances; Ruiz, Michael J.

    2015-01-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step…

  14. [Autoimmune processes after long-term low-level exposure to electromagnetic fields (the results of an experiment). Part 1. Mobile communications and changes in electromagnetic conditions for the population. Needs for additional substantiation of the existing hygienic standards].

    PubMed

    Grigor'ev, Iu G; Grigor'ev, O A; Ivanov, A A; Liaginskaia, A M; Merkulov, A V; Stepanov, V S; Shagina, N B

    2010-01-01

    Mobile communications provides a new source of electromagnetic exposure for almost the whole population of the Russian Federation. For the first time in the history of civilization the brain of mobile phone users was exposed to localized radiofrequency (RF) electromagnetic fields (EMF). Population exposure from the base stations is also considered to be specific. However, existing standards for limiting the exposure do not account for this special EMF source and may not ensure the absence of health effects. There was a need for reliable information that would extend databases used for development of new standards. As recommended by the World Health Organization an additional experiment was performed under the supervision of foreign experts, which showed changes in autoimmune status in rats after long-term low-level RF EMF exposure with an incident power density of 500 microW/cm2.

  15. Revealing Rembrandt

    PubMed Central

    Parker, Andrew J.

    2014-01-01

    The power and significance of artwork in shaping human cognition is self-evident. The starting point for our empirical investigations is the view that the task of neuroscience is to integrate itself with other forms of knowledge, rather than to seek to supplant them. In our recent work, we examined a particular aspect of the appreciation of artwork using present-day functional magnetic resonance imaging (fMRI). Our results emphasized the continuity between viewing artwork and other human cognitive activities. We also showed that appreciation of a particular aspect of artwork, namely authenticity, depends upon the co-ordinated activity between the brain regions involved in multiple decision making and those responsible for processing visual information. The findings about brain function probably have no specific consequences for understanding how people respond to the art of Rembrandt in comparison with their response to other artworks. However, the use of images of Rembrandt's portraits, his most intimate and personal works, clearly had a significant impact upon our viewers, even though they have been spatially confined to the interior of an MRI scanner at the time of viewing. Neuroscientific studies of humans viewing artwork have the capacity to reveal the diversity of human cognitive responses that may be induced by external advice or context as people view artwork in a variety of frameworks and settings. PMID:24795552

  16. Is it efficient to co-compost and co-vermicompost green waste with biochar and/or clay to reduce CO2 emissions? A short-term laboratory experiment on (vermi)composts with additives.

    NASA Astrophysics Data System (ADS)

    Barthod, Justine; Rumpel, Cornélia; Paradelo, Remigio; Dignac, Marie-France

    2016-04-01

    Intensive farming practices can lead to a depletion of soil organic matter, negatively impacting important soil properties such as structural stability, fertility and C storage. The addition of organic amendments such as compost and vermicompost, rich in carbon, helps maintaining soil organic matter levels or restoring degraded soils. Composting and vermicomposting are based on stabilization of organic matter through the mineralization of easily decomposable organic matter compounds, therefore releasing greenhouse gases, including CO2. The aim of this study was to evaluate the global potential reduction of such emissions by the use of additives (2:1 clay and/or biochar): during (vermi)composting processes and after use of the final products as soil amendments. We hypothesized that the interactions between the additives and organic matter may lead to carbon stabilization and that such interactions may be enhanced by the presence of worms (Eisenia). We added in different proportions clay (25% or 50%), biochar (10%) and a mixture of biochar (10%) with clay (25%) to pre-composted green waste. The CO2 emissions of the composting and vermicomposting processes were measured during 21 days. After that, the amendments were added to a loamy cambisol soil and the CO2 emissions were monitored during 30 days of a laboratory experiment. The most efficient treatments in terms of reducing global CO2 emissions were the co-vermicomposting process with 25% clay followed by co-composting with 50% clay and with 10% biochar plus 25% clay. In this treatment (vermicompost with 25% clay), the carbon emissions were decreased by up to 44% compared to regular compost. Addition of biochar reduced CO2 emissions only during composting. Co-composting with biochar could be a promising avenue to limit global CO2 emissions whereas in presence of worms clay additions are better suited. These findings suggest that the presence of worms increased the formation of organo-mineral associations and thus C

  17. Color Addition and Subtraction Apps

    NASA Astrophysics Data System (ADS)

    Ruiz, Frances; Ruiz, Michael J.

    2015-10-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step in understanding mathematical representations of RGB color. Finally, color addition and subtraction are presented for the X11 colors from web design to illustrate yet another real-life application of color mixing.

  18. Additive Similarity Trees

    ERIC Educational Resources Information Center

    Sattath, Shmuel; Tversky, Amos

    1977-01-01

    Tree representations of similarity data are investigated. Hierarchical clustering is critically examined, and a more general procedure, called the additive tree, is presented. The additive tree representation is then compared to multidimensional scaling. (Author/JKS)

  19. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. R.; St. Clair, T. L.; Burks, H. D.; Stoakley, D. M.

    1987-01-01

    A method has been found for enhancing the melt flow of thermoplastic polyimides during processing. A high molecular weight 422 copoly(amic acid) or copolyimide was fused with approximately 0.05 to 5 pct by weight of a low molecular weight amic acid or imide additive, and this melt was studied by capillary rheometry. Excellent flow and improved composite properties on graphite resulted from the addition of a PMDA-aniline additive to LARC-TPI. Solution viscosity studies imply that amic acid additives temporarily lower molecular weight and, hence, enlarge the processing window. Thus, compositions containing the additive have a lower melt viscosity for a longer time than those unmodified.

  20. [Food additives and healthiness].

    PubMed

    Heinonen, Marina

    2014-01-01

    Additives are used for improving food structure or preventing its spoilage, for example. Many substances used as additives are also naturally present in food. The safety of additives is evaluated according to commonly agreed principles. If high concentrations of an additive cause adverse health effects for humans, a limit of acceptable daily intake (ADI) is set for it. An additive is a risk only when ADI is exceeded. The healthiness of food is measured on the basis of nutrient density and scientifically proven effects.

  1. Polylactides in additive biomanufacturing.

    PubMed

    Poh, Patrina S P; Chhaya, Mohit P; Wunner, Felix M; De-Juan-Pardo, Elena M; Schilling, Arndt F; Schantz, Jan-Thorsten; van Griensven, Martijn; Hutmacher, Dietmar W

    2016-12-15

    New advanced manufacturing technologies under the alias of additive biomanufacturing allow the design and fabrication of a range of products from pre-operative models, cutting guides and medical devices to scaffolds. The process of printing in 3 dimensions of cells, extracellular matrix (ECM) and biomaterials (bioinks, powders, etc.) to generate in vitro and/or in vivo tissue analogue structures has been termed bioprinting. To further advance in additive biomanufacturing, there are many aspects that we can learn from the wider additive manufacturing (AM) industry, which have progressed tremendously since its introduction into the manufacturing sector. First, this review gives an overview of additive manufacturing and both industry and academia efforts in addressing specific challenges in the AM technologies to drive toward AM-enabled industrial revolution. After which, considerations of poly(lactides) as a biomaterial in additive biomanufacturing are discussed. Challenges in wider additive biomanufacturing field are discussed in terms of (a) biomaterials; (b) computer-aided design, engineering and manufacturing; (c) AM and additive biomanufacturing printers hardware; and (d) system integration. Finally, the outlook for additive biomanufacturing was discussed.

  2. Additive Manufactured Product Integrity

    NASA Technical Reports Server (NTRS)

    Waller, Jess; Wells, Doug; James, Steve; Nichols, Charles

    2017-01-01

    NASA is providing key leadership in an international effort linking NASA and non-NASA resources to speed adoption of additive manufacturing (AM) to meet NASA's mission goals. Participants include industry, NASA's space partners, other government agencies, standards organizations and academia. Nondestructive Evaluation (NDE) is identified as a universal need for all aspects of additive manufacturing.

  3. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Fletcher, James C. (Inventor); Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1992-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  4. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1993-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of the additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  5. Food Additives and Hyperkinesis

    ERIC Educational Resources Information Center

    Wender, Ester H.

    1977-01-01

    The hypothesis that food additives are causally associated with hyperkinesis and learning disabilities in children is reviewed, and available data are summarized. Available from: American Medical Association 535 North Dearborn Street Chicago, Illinois 60610. (JG)

  6. Smog control fuel additives

    SciTech Connect

    Lundby, W.

    1993-06-29

    A method is described of controlling, reducing or eliminating, ozone and related smog resulting from photochemical reactions between ozone and automotive or industrial gases comprising the addition of iodine or compounds of iodine to hydrocarbon-base fuels prior to or during combustion in an amount of about 1 part iodine per 240 to 10,000,000 parts fuel, by weight, to be accomplished by: (a) the addition of these inhibitors during or after the refining or manufacturing process of liquid fuels; (b) the production of these inhibitors for addition into fuel tanks, such as automotive or industrial tanks; or (c) the addition of these inhibitors into combustion chambers of equipment utilizing solid fuels for the purpose of reducing ozone.

  7. Quantitative shotgun proteomics using a uniform ¹⁵N-labeled standard to monitor proteome dynamics in time course experiments reveals new insights into the heat stress response of Chlamydomonas reinhardtii.

    PubMed

    Mühlhaus, Timo; Weiss, Julia; Hemme, Dorothea; Sommer, Frederik; Schroda, Michael

    2011-09-01

    Crop-plant-yield safety is jeopardized by temperature stress caused by the global climate change. To take countermeasures by breeding and/or transgenic approaches it is essential to understand the mechanisms underlying plant acclimation to heat stress. To this end proteomics approaches are most promising, as acclimation is largely mediated by proteins. Accordingly, several proteomics studies, mainly based on two-dimensional gel-tandem MS approaches, were conducted in the past. However, results often were inconsistent, presumably attributable to artifacts inherent to the display of complex proteomes via two-dimensional-gels. We describe here a new approach to monitor proteome dynamics in time course experiments. This approach involves full ¹⁵N metabolic labeling and mass spectrometry based quantitative shotgun proteomics using a uniform ¹⁵N standard over all time points. It comprises a software framework, IOMIQS, that features batch job mediated automated peptide identification by four parallelized search engines, peptide quantification and data assembly for the processing of large numbers of samples. We have applied this approach to monitor proteome dynamics in a heat stress time course using the unicellular green alga Chlamydomonas reinhardtii as model system. We were able to identify 3433 Chlamydomonas proteins, of which 1116 were quantified in at least three of five time points of the time course. Statistical analyses revealed that levels of 38 proteins significantly increased, whereas levels of 206 proteins significantly decreased during heat stress. The increasing proteins comprise 25 (co-)chaperones and 13 proteins involved in chromatin remodeling, signal transduction, apoptosis, photosynthetic light reactions, and yet unknown functions. Proteins decreasing during heat stress were significantly enriched in functional categories that mediate carbon flux from CO₂ and external acetate into protein biosynthesis, which also correlated with a rapid, but

  8. Additive Manufacturing Infrared Inspection

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell

    2014-01-01

    Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

  9. Phenylethynyl Containing Reactive Additives

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

    2002-01-01

    Phenylethynyl containing reactive additives were prepared from aromatic diamine, containing phenylethvnvl groups and various ratios of phthalic anhydride and 4-phenylethynviphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pvrrolidinone to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

  10. Fused Lasso Additive Model

    PubMed Central

    Petersen, Ashley; Witten, Daniela; Simon, Noah

    2016-01-01

    We consider the problem of predicting an outcome variable using p covariates that are measured on n independent observations, in a setting in which additive, flexible, and interpretable fits are desired. We propose the fused lasso additive model (FLAM), in which each additive function is estimated to be piecewise constant with a small number of adaptively-chosen knots. FLAM is the solution to a convex optimization problem, for which a simple algorithm with guaranteed convergence to a global optimum is provided. FLAM is shown to be consistent in high dimensions, and an unbiased estimator of its degrees of freedom is proposed. We evaluate the performance of FLAM in a simulation study and on two data sets. Supplemental materials are available online, and the R package flam is available on CRAN. PMID:28239246

  11. Phenylethynyl Containing Reactive Additives

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

    2002-01-01

    Phenylethynyl containing reactive additives were prepared from aromatic diamines containing phenylethynyl groups and various ratios of phthalic anhydride and 4-phenylethynylphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pyrrolidi none to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

  12. Additives in plastics.

    PubMed Central

    Deanin, R D

    1975-01-01

    The polymers used in plastics are generally harmless. However, they are rarely used in pure form. In almost all commercial plastics, they are "compounded" with monomeric ingredients to improve their processing and end-use performance. In order of total volume used, these monomeric additives may be classified as follows: reinforcing fibers, fillers, and coupling agents; plasticizers; colorants; stabilizers (halogen stabilizers, antioxidants, ultraviolet absorbers, and biological preservatives); processing aids (lubricants, others, and flow controls); flame retardants, peroxides; and antistats. Some information is already available, and much more is needed, on potential toxicity and safe handling of these additives during processing and manufacture of plastics products. PMID:1175566

  13. Additives in plastics.

    PubMed

    Deanin, R D

    1975-06-01

    The polymers used in plastics are generally harmless. However, they are rarely used in pure form. In almost all commercial plastics, they are "compounded" with monomeric ingredients to improve their processing and end-use performance. In order of total volume used, these monomeric additives may be classified as follows: reinforcing fibers, fillers, and coupling agents; plasticizers; colorants; stabilizers (halogen stabilizers, antioxidants, ultraviolet absorbers, and biological preservatives); processing aids (lubricants, others, and flow controls); flame retardants, peroxides; and antistats. Some information is already available, and much more is needed, on potential toxicity and safe handling of these additives during processing and manufacture of plastics products.

  14. Biobased lubricant additives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fully biobased lubricants are those formulated using all biobased ingredients, i.e. biobased base oils and biobased additives. Such formulations provide the maximum environmental, safety, and economic benefits expected from a biobased product. Currently, there are a number of biobased base oils that...

  15. More Than Additional Space...

    ERIC Educational Resources Information Center

    CEFP Journal, 1973

    1973-01-01

    A much needed addition to the Jamestown Elementary School turned out to be more than an expansion of walls for more space. A new educational program, a limited budget, and a short time line were tackled on a team approach basis and were successfully resolved. (Author)

  16. Vinyl capped addition polyimides

    NASA Technical Reports Server (NTRS)

    Vannucci, Raymond D. (Inventor); Malarik, Diane C. (Inventor); Delvigs, Peter (Inventor)

    1991-01-01

    Polyimide resins (PMR) are generally useful where high strength and temperature capabilities are required (at temperatures up to about 700 F). Polyimide resins are particularly useful in applications such as jet engine compressor components, for example, blades, vanes, air seals, air splitters, and engine casing parts. Aromatic vinyl capped addition polyimides are obtained by reacting a diamine, an ester of tetracarboxylic acid, and an aromatic vinyl compound. Low void materials with improved oxidative stability when exposed to 700 F air may be fabricated as fiber reinforced high molecular weight capped polyimide composites. The aromatic vinyl capped polyimides are provided with a more aromatic nature and are more thermally stable than highly aliphatic, norbornenyl-type end-capped polyimides employed in PMR resins. The substitution of aromatic vinyl end-caps for norbornenyl end-caps in addition polyimides results in polymers with improved oxidative stability.

  17. Electrophilic addition of astatine

    SciTech Connect

    Norseev, Yu.V.; Vasaros, L.; Nhan, D.D.; Huan, N.K.

    1988-03-01

    It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.

  18. Functional Generalized Additive Models.

    PubMed

    McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

    2014-01-01

    We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online.

  19. Siloxane containing addition polyimides

    NASA Technical Reports Server (NTRS)

    Maudgal, S.; St. Clair, T. L.

    1984-01-01

    Addition polyimide oligomers have been synthesized from bis(gamma-aminopropyl) tetramethyldisiloxane and 3, 3', 4, 4'-benzophenonetetracarboxylic dianhydride using a variety of latent crosslinking groups as endcappers. The prepolymers were isolated and characterized for solubility (in amide, chlorinated and ether solvents), melt flow and cure properties. The most promising systems, maleimide and acetylene terminated prepolymers, were selected for detailed study. Graphite cloth reinforced composites were prepared and properties compared with those of graphite/Kerimid 601, a commercially available bismaleimide. Mixtures of the maleimide terminated system with Kerimid 601, in varying proportions, were also studied.

  20. The Additive Coloration of Alkali Halides

    ERIC Educational Resources Information Center

    Jirgal, G. H.; and others

    1969-01-01

    Describes the construction and use of an inexpensive, vacuum furnace designed to produce F-centers in alkali halide crystals by additive coloration. The method described avoids corrosion or contamination during the coloration process. Examination of the resultant crystals is discussed and several experiments using additively colored crystals are…

  1. Platelet additive solution - electrolytes.

    PubMed

    Azuma, Hiroshi; Hirayama, Junichi; Akino, Mitsuaki; Ikeda, Hisami

    2011-06-01

    Recent attention to solutions that replace most or all plasma in platelet concentrates, while maintaining satisfactory platelet function, is motivated by the potential of plasma reduction or depletion to mitigate various transfusion-related adverse events. This report considers the electrolytic composition of previously described platelet additive solutions, in order to draw general conclusions about what is required for platelet function and longevity. The optimal concentrations of Na(+) and Cl(-) are 69-115 mM. The presence of both K(+) and Mg(2+) in platelet suspension at nearly physiological concentrations (3-5mM and 1.5-3mM, respectively) is indispensable for good preservation capacity because both electrolytes are required to prevent platelet activation. In contrast to K(+) and Mg(2+), Ca(2+) may not be important because no free Ca(2+) is available in M-sol, which showed excellent platelet preservation capacity at less than 5% plasma concentration. The importance of bicarbonate (approximately 40 mM) can be recognized when the platelets are suspended in additive solution under less than 5% residual plasma concentration.

  2. Additive composition, for gasoline

    SciTech Connect

    Vataru, M.

    1989-01-10

    An admixture is described that comprises Diesel fuel and an additive composition added thereto which is between about 0.05 to about 2.0 percent by weight of the fuel, the composition comprising: (a) between about 0.05 and 25% relative weight parts of an organic peroxide, and (b) between about 0.1 and 25% relative weight parts of detergent selected from the component group that consists of: (i) fatty amines; (ii) ethoxylated and propoxylated derivatives of fatty amines; (iii) fatty diamines; (iv) fatty imidazlines; (v) polymeric amines and derivatives thereof; (vi) combination of one or more of the (i) through (v) components with carboxylic acid or acids having from three to forth carbon atoms, (c) from about 99.0 to about 50% by weight of a hydrocarbon solvent.

  3. Teardrop bladder: additional considerations

    SciTech Connect

    Wechsler, R.J.; Brennan, R.E.

    1982-07-01

    Nine cases of teardrop bladder (TDB) seen at excretory urography are presented. In some of these patients, the iliopsoas muscles were at the upper limit of normal in size, and additional evaluation of the perivesical structures with computed tomography (CT) was necessary. CT demonstrated only hypertrophied muscles with or without perivesical fat. The psoas muscles and pelvic width were measured in 8 patients and compared with the measurements of a control group of males without TDB. Patients with TDB had large iliopsoas muscles and narrow pelves compared with the control group. The psoas muscle width/pelvic width ratio was significantly greater (p < 0.0005) in patients with TDB than in the control group, with values of 1.04 + 0.05 and 0.82 + 0.09, respectively. It is concluded that TDB is not an uncommon normal variant in black males. Both iliopsoas muscle hypertrophy and a narrow pelvis are factors that predispose a patient to TDB.

  4. New addition curing polyimides

    NASA Technical Reports Server (NTRS)

    Frimer, Aryeh A.; Cavano, Paul

    1991-01-01

    In an attempt to improve the thermal-oxidative stability (TOS) of PMR-type polymers, the use of 1,4-phenylenebis (phenylmaleic anhydride) PPMA, was evaluated. Two series of nadic end-capped addition curing polyimides were prepared by imidizing PPMA with either 4,4'-methylene dianiline or p-phenylenediamine. The first resulted in improved solubility and increased resin flow while the latter yielded a compression molded neat resin sample with a T(sub g) of 408 C, close to 70 C higher than PME-15. The performance of these materials in long term weight loss studies was below that of PMR-15, independent of post-cure conditions. These results can be rationalized in terms of the thermal lability of the pendant phenyl groups and the incomplete imidization of the sterically congested PPMA. The preparation of model compounds as well as future research directions are discussed.

  5. Perspectives on Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Bourell, David L.

    2016-07-01

    Additive manufacturing (AM) has skyrocketed in visibility commercially and in the public sector. This article describes the development of this field from early layered manufacturing approaches of photosculpture, topography, and material deposition. Certain precursors to modern AM processes are also briefly described. The growth of the field over the last 30 years is presented. Included is the standard delineation of AM technologies into seven broad categories. The economics of AM part generation is considered, and the impacts of the economics on application sectors are described. On the basis of current trends, the future outlook will include a convergence of AM fabricators, mass-produced AM fabricators, enabling of topology optimization designs, and specialization in the AM legal arena. Long-term developments with huge impact are organ printing and volume-based printing.

  6. Sewage sludge additive

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  7. Additive lattice kirigami.

    PubMed

    Castle, Toen; Sussman, Daniel M; Tanis, Michael; Kamien, Randall D

    2016-09-01

    Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes.

  8. Ceramics with Different Additives

    NASA Astrophysics Data System (ADS)

    Wang, Juanjuan; Feng, Lajun; Lei, Ali; Zhao, Kang; Yan, Aijun

    2014-09-01

    Li2CO3, MgCO3, BaCO3, and Bi2O3 dopants were introduced into CaCu3Ti4O12 (CCTO) ceramics in order to improve the dielectric properties. The CCTO ceramics were prepared by conventional solid-state reaction method. The phase structure, microstructure, and dielectric behavior were carefully investigated. The pure structure without any impurity phases can be confirmed by the x-ray diffraction patterns. Scanning Electron Microscopy (SEM) analysis illuminated that the grains of Ca0.90Li0.20Cu3Ti4O12 ceramics were greater than that of pure CCTO. It was important for the properties of the CCTO ceramics to study the additives in complex impedance spectroscopy. It was found that the Ca0.90Li0.20Cu3Ti4O12 ceramics had the higher permittivity (>45000), the lower dielectric loss (<0.025) than those of CCTO at 1 kHz at room temperature and good temperature stability from -30 to 75 °C.

  9. Additive lattice kirigami

    PubMed Central

    Castle, Toen; Sussman, Daniel M.; Tanis, Michael; Kamien, Randall D.

    2016-01-01

    Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes. PMID:27679822

  10. An Additive Manufacturing Test Artifact

    PubMed Central

    Moylan, Shawn; Slotwinski, John; Cooke, April; Jurrens, Kevin; Donmez, M Alkan

    2014-01-01

    A test artifact, intended for standardization, is proposed for the purpose of evaluating the performance of additive manufacturing (AM) systems. A thorough analysis of previously proposed AM test artifacts as well as experience with machining test artifacts have inspired the design of the proposed test artifact. This new artifact is designed to provide a characterization of the capabilities and limitations of an AM system, as well as to allow system improvement by linking specific errors measured in the test artifact to specific sources in the AM system. The proposed test artifact has been built in multiple materials using multiple AM technologies. The results of several of the builds are discussed, demonstrating how the measurement results can be used to characterize and improve a specific AM system. PMID:26601039

  11. An Additive Manufacturing Test Artifact.

    PubMed

    Moylan, Shawn; Slotwinski, John; Cooke, April; Jurrens, Kevin; Donmez, M Alkan

    2014-01-01

    A test artifact, intended for standardization, is proposed for the purpose of evaluating the performance of additive manufacturing (AM) systems. A thorough analysis of previously proposed AM test artifacts as well as experience with machining test artifacts have inspired the design of the proposed test artifact. This new artifact is designed to provide a characterization of the capabilities and limitations of an AM system, as well as to allow system improvement by linking specific errors measured in the test artifact to specific sources in the AM system. The proposed test artifact has been built in multiple materials using multiple AM technologies. The results of several of the builds are discussed, demonstrating how the measurement results can be used to characterize and improve a specific AM system.

  12. Rhodium-Catalyzed Enantioselective Vinylogous Addition of Enol Ethers to Vinyldiazoacetates

    PubMed Central

    Smith, Austin G.; Davies, Huw M. L.

    2012-01-01

    A highly asymmetric vinylogous addition of acyclic silyl enol ethers to siloxyvinyldiazoacetate is described. The reaction features a diastereoselective 1,4-siloxy group migration event. Products are obtained in up to 97% ee. When more sterically crowded silyl enol ethers are employed, an enantioselective formal [3 + 2] cycloaddition becomes the dominant reaction pathway. Control experiments reveal the (Z)-olefin geometry to be critical for high levels of enantiocontrol. PMID:23098215

  13. Neutron Characterization for Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Watkins, Thomas; Bilheux, Hassina; An, Ke; Payzant, Andrew; DeHoff, Ryan; Duty, Chad; Peter, William; Blue, Craig; Brice, Craig A.

    2013-01-01

    Oak Ridge National Laboratory (ORNL) is leveraging decades of experience in neutron characterization of advanced materials together with resources such as the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR) shown in Fig. 1 to solve challenging problems in additive manufacturing (AM). Additive manufacturing, or three-dimensional (3-D) printing, is a rapidly maturing technology wherein components are built by selectively adding feedstock material at locations specified by a computer model. The majority of these technologies use thermally driven phase change mechanisms to convert the feedstock into functioning material. As the molten material cools and solidifies, the component is subjected to significant thermal gradients, generating significant internal stresses throughout the part (Fig. 2). As layers are added, inherent residual stresses cause warping and distortions that lead to geometrical differences between the final part and the original computer generated design. This effect also limits geometries that can be fabricated using AM, such as thin-walled, high-aspect- ratio, and overhanging structures. Distortion may be minimized by intelligent toolpath planning or strategic placement of support structures, but these approaches are not well understood and often "Edisonian" in nature. Residual stresses can also impact component performance during operation. For example, in a thermally cycled environment such as a high-pressure turbine engine, residual stresses can cause components to distort unpredictably. Different thermal treatments on as-fabricated AM components have been used to minimize residual stress, but components still retain a nonhomogeneous stress state and/or demonstrate a relaxation-derived geometric distortion. Industry, federal laboratory, and university collaboration is needed to address these challenges and enable the U.S. to compete in the global market. Work is currently being conducted on AM technologies at the ORNL

  14. Priming Addition Facts with Semantic Relations

    ERIC Educational Resources Information Center

    Bassok, Miriam; Pedigo, Samuel F.; Oskarsson, An T.

    2008-01-01

    Results from 2 relational-priming experiments suggest the existence of an automatic analogical coordination between semantic and arithmetic relations. Word pairs denoting object sets served as primes in a task that elicits "obligatory" activation of addition facts (5 + 3 activates 8; J. LeFevre, J. Bisanz, & L. Mrkonjic, 1988). Semantic relations…

  15. Revealing ontological commitments by magic.

    PubMed

    Griffiths, Thomas L

    2015-03-01

    Considering the appeal of different magical transformations exposes some systematic asymmetries. For example, it is more interesting to transform a vase into a rose than a rose into a vase. An experiment in which people judged how interesting they found different magic tricks showed that these asymmetries reflect the direction a transformation moves in an ontological hierarchy: transformations in the direction of animacy and intelligence are favored over the opposite. A second and third experiment demonstrated that judgments of the plausibility of machines that perform the same transformations do not show the same asymmetries, but judgments of the interestingness of such machines do. A formal argument relates this sense of interestingness to evidence for an alternative to our current physical theory, with magic tricks being a particularly pure source of such evidence. These results suggest that people's intuitions about magic tricks can reveal the ontological commitments that underlie human cognition.

  16. Priming addition facts with semantic relations.

    PubMed

    Bassok, Miriam; Pedigo, Samuel F; Oskarsson, An T

    2008-03-01

    Results from 2 relational-priming experiments suggest the existence of an automatic analogical coordination between semantic and arithmetic relations. Word pairs denoting object sets served as primes in a task that elicits "obligatory" activation of addition facts (5 + 3 activates 8; J. LeFevre, J. Bisanz, & L. Mrkonjic, 1988). Semantic relations between the priming words were either aligned or misaligned with the structure of addition (M. Bassok, V. M. Chase, & S. A. Martin, 1998). Obligatory activation of addition facts occurred when the digits were primed by categorically related words (tulips-daisies), which are aligned with addition, but did not occur when the digits were primed by unrelated words (hens-radios, Experiment 1) or by functionally related words (records-songs, Experiment 2), which are misaligned with addition. These findings lend support to the viability of automatic analogical priming (B. A. Spellman, K. J. Holyoak, & R. G. Morrison, 2001) and highlight the relevance of arithmetic applications to theoretical accounts of mental arithmetic.

  17. Experiment Databases

    NASA Astrophysics Data System (ADS)

    Vanschoren, Joaquin; Blockeel, Hendrik

    Next to running machine learning algorithms based on inductive queries, much can be learned by immediately querying the combined results of many prior studies. Indeed, all around the globe, thousands of machine learning experiments are being executed on a daily basis, generating a constant stream of empirical information on machine learning techniques. While the information contained in these experiments might have many uses beyond their original intent, results are typically described very concisely in papers and discarded afterwards. If we properly store and organize these results in central databases, they can be immediately reused for further analysis, thus boosting future research. In this chapter, we propose the use of experiment databases: databases designed to collect all the necessary details of these experiments, and to intelligently organize them in online repositories to enable fast and thorough analysis of a myriad of collected results. They constitute an additional, queriable source of empirical meta-data based on principled descriptions of algorithm executions, without reimplementing the algorithms in an inductive database. As such, they engender a very dynamic, collaborative approach to experimentation, in which experiments can be freely shared, linked together, and immediately reused by researchers all over the world. They can be set up for personal use, to share results within a lab or to create open, community-wide repositories. Here, we provide a high-level overview of their design, and use an existing experiment database to answer various interesting research questions about machine learning algorithms and to verify a number of recent studies.

  18. Hiding personal information reveals the worst

    PubMed Central

    John, Leslie K.; Barasz, Kate; Norton, Michael I.

    2016-01-01

    Seven experiments explore people’s decisions to share or withhold personal information, and the wisdom of such decisions. When people choose not to reveal information—to be “hiders”—they are judged negatively by others (experiment 1). These negative judgments emerge when hiding is volitional (experiments 2A and 2B) and are driven by decreases in trustworthiness engendered by decisions to hide (experiments 3A and 3B). Moreover, hiders do not intuit these negative consequences: given the choice to withhold or reveal unsavory information, people often choose to withhold, but observers rate those who reveal even questionable behavior more positively (experiments 4A and 4B). The negative impact of hiding holds whether opting not to disclose unflattering (drug use, poor grades, and sexually transmitted diseases) or flattering (blood donations) information, and across decisions ranging from whom to date to whom to hire. When faced with decisions about disclosure, decision-makers should be aware not just of the risk of revealing, but of what hiding reveals. PMID:26755591

  19. Analysis of positive control STR experiments reveals that results obtained for FGA, D3S1358, and D13S317 condition the success rate of the analysis of routine reference samples.

    PubMed

    Murigneux, Valentine; Dufour, Anne-Béatrice; Lobry, Jean R; Pène, Laurent

    2014-07-01

    About 120,000 reference samples are analyzed each year in the Forensic Laboratory of Lyon. A total of 1640 positive control experiments used to validate and optimize the analytical method in the routine process were submitted to a multivariate exploratory data analysis approach with the aim of better understanding the underlying sources of variability. The peak heights of the 16 genetic markers targeted by the AmpFℓSTR(®) Identifiler(®) STR kit were used as variables of interest. Six different 3130xl genetic analyzers located in the same controlled environment were involved. Two major sources of variability were found: (i) the DNA load of the sample modulates all peak heights in a similar way so that the 16 markers are highly correlated, (ii) the genetic analyzer used with a locus-specific response for peak height and a better sensitivity for the most recently acquired. Three markers (FGA, D3S1358, and D13S317) were found to be of special interest to predict the success rate observed in the routine process.

  20. An Examination of Game-Based Learning from Theories of Flow Experience and Cognitive Load

    ERIC Educational Resources Information Center

    Lai, Chih-Hung; Chu, Chih-Ming; Liu, Hsiang-Hsuan; Yang, Shun-Bo; Chen, Wei-Hsuan

    2013-01-01

    This study aims to discuss whether game-based learning with the integration of games and digital learning could enhance not only the flow experience in learning but achieve the same flow experience in pure games. In addition, the authors discovered that whether the game-based learning could make learners to reveal higher cognitive load. The…

  1. How Safe Are Color Additives?

    MedlinePlus

    ... Home For Consumers Consumer Updates How Safe are Color Additives? Share Tweet Linkedin Pin it More sharing ... Consumer Updates RSS Feed Download PDF (380 K) Color additives give the red tint to your fruit ...

  2. Detergent Additive for Lubricating Oils,

    DTIC Science & Technology

    The Russian patent pertains to a method of producing additives for lubricating oils . A method is known for producing an antiwear additive for... lubricating oils by processing phenols with phosphorus oxychloride, phosphoric acid esters are obtained. In order to give the additive detergent properties

  3. Alpenglow: A signature for chameleons in axionlike particle search experiments

    SciTech Connect

    Ahlers, M.; Lindner, A.; Ringwald, A.; Schrempp, L.; Weniger, C.

    2008-01-01

    We point out that chameleon field theories might reveal themselves as an afterglow effect in axionlike particle search experiments due to chameleon-photon conversion in a magnetic field. We estimate the parameter space which is accessible by currently available technology and find that afterglow experiments could constrain this parameter space in a way complementary to gravitational and Casimir force experiments. In addition, one could reach photon-chameleon couplings which are beyond the sensitivity of common laser polarization experiments. We also sketch the idea of a Fabry-Perot cavity with chameleons which could increase the experimental sensitivity significantly.

  4. Incorporation of additives into polymers

    DOEpatents

    McCleskey, T. Mark; Yates, Matthew Z.

    2003-07-29

    There has been invented a method for incorporating additives into polymers comprising: (a) forming an aqueous or alcohol-based colloidal system of the polymer; (b) emulsifying the colloidal system with a compressed fluid; and (c) contacting the colloidal polymer with the additive in the presence of the compressed fluid. The colloidal polymer can be contacted with the additive by having the additive in the compressed fluid used for emulsification or by adding the additive to the colloidal system before or after emulsification with the compressed fluid. The invention process can be carried out either as a batch process or as a continuous on-line process.

  5. Additive manufacturing of optical components

    NASA Astrophysics Data System (ADS)

    Heinrich, Andreas; Rank, Manuel; Maillard, Philippe; Suckow, Anne; Bauckhage, Yannick; Rößler, Patrick; Lang, Johannes; Shariff, Fatin; Pekrul, Sven

    2016-08-01

    The development of additive manufacturing methods has enlarged rapidly in recent years. Thereby, the work mainly focuses on the realization of mechanical components, but the additive manufacturing technology offers a high potential in the field of optics as well. Owing to new design possibilities, completely new solutions are possible. This article briefly reviews and compares the most important additive manufacturing methods for polymer optics. Additionally, it points out the characteristics of additive manufactured polymer optics. Thereby, surface quality is of crucial importance. In order to improve it, appropriate post-processing steps are necessary (e.g. robot polishing or coating), which will be discussed. An essential part of this paper deals with various additive manufactured optical components and their use, especially in optical systems for shape metrology (e.g. borehole sensor, tilt sensor, freeform surface sensor, fisheye lens). The examples should demonstrate the potentials and limitations of optical components produced by additive manufacturing.

  6. Adaptation to High Ethanol Reveals Complex Evolutionary Pathways

    PubMed Central

    Das, Anupam; Espinosa-Cantú, Adriana; De Maeyer, Dries; Arslan, Ahmed; Van Pee, Michiel; van der Zande, Elisa; Meert, Wim; Yang, Yudi; Zhu, Bo; Marchal, Kathleen; DeLuna, Alexander; Van Noort, Vera; Jelier, Rob; Verstrepen, Kevin J.

    2015-01-01

    Tolerance to high levels of ethanol is an ecologically and industrially relevant phenotype of microbes, but the molecular mechanisms underlying this complex trait remain largely unknown. Here, we use long-term experimental evolution of isogenic yeast populations of different initial ploidy to study adaptation to increasing levels of ethanol. Whole-genome sequencing of more than 30 evolved populations and over 100 adapted clones isolated throughout this two-year evolution experiment revealed how a complex interplay of de novo single nucleotide mutations, copy number variation, ploidy changes, mutator phenotypes, and clonal interference led to a significant increase in ethanol tolerance. Although the specific mutations differ between different evolved lineages, application of a novel computational pipeline, PheNetic, revealed that many mutations target functional modules involved in stress response, cell cycle regulation, DNA repair and respiration. Measuring the fitness effects of selected mutations introduced in non-evolved ethanol-sensitive cells revealed several adaptive mutations that had previously not been implicated in ethanol tolerance, including mutations in PRT1, VPS70 and MEX67. Interestingly, variation in VPS70 was recently identified as a QTL for ethanol tolerance in an industrial bio-ethanol strain. Taken together, our results show how, in contrast to adaptation to some other stresses, adaptation to a continuous complex and severe stress involves interplay of different evolutionary mechanisms. In addition, our study reveals functional modules involved in ethanol resistance and identifies several mutations that could help to improve the ethanol tolerance of industrial yeasts. PMID:26545090

  7. Enantioselective Michael addition of water.

    PubMed

    Chen, Bi-Shuang; Resch, Verena; Otten, Linda G; Hanefeld, Ulf

    2015-02-09

    The enantioselective Michael addition using water as both nucleophile and solvent has to date proved beyond the ability of synthetic chemists. Herein, the direct, enantioselective Michael addition of water in water to prepare important β-hydroxy carbonyl compounds using whole cells of Rhodococcus strains is described. Good yields and excellent enantioselectivities were achieved with this method. Deuterium labeling studies demonstrate that a Michael hydratase catalyzes the water addition exclusively with anti-stereochemistry.

  8. Enantioselective Michael Addition of Water

    PubMed Central

    Chen, Bi-Shuang; Resch, Verena; Otten, Linda G; Hanefeld, Ulf

    2015-01-01

    The enantioselective Michael addition using water as both nucleophile and solvent has to date proved beyond the ability of synthetic chemists. Herein, the direct, enantioselective Michael addition of water in water to prepare important β-hydroxy carbonyl compounds using whole cells of Rhodococcus strains is described. Good yields and excellent enantioselectivities were achieved with this method. Deuterium labeling studies demonstrate that a Michael hydratase catalyzes the water addition exclusively with anti-stereochemistry. PMID:25529526

  9. Thermal Response of an Additive Manufactured Aluminum

    SciTech Connect

    Wu, Tong; Wereszczak, Andrew A; Wang, Hsin; Ozpineci, Burak; Ayers, Curtis William

    2016-01-01

    In this paper, the impacts of abnormal thermal property introduced by additive manufacture has been analysis based on simulation and experiment of a 3D printed liquid-cooled heat sink. Comparisons to the heat sink with identical geometry and conventionally manufactured by Aluminum 6061 are presented. Micro-structure analysis is implemented and solutions to eliminate the impacts by different manufacture methods are proposed.

  10. Plan competitions reveal entrepreneurial talent

    SciTech Connect

    Madison, Alison L.

    2011-05-15

    Monthly economic diversity column for Tri-City Herald business section. Excerpt below: There’s something to be said for gaining valuable real-world experience in a structured, nurturing environment. Take for instance learning to scuba dive in the comfort of my resort pool rather than immediately hanging out with sharks while I figure out little things like oxygen tanks and avoiding underwater panic attacks. Likewise, graduate students are getting some excellent, supportive real-world training through university business plan competitions. These competitions are places where smart minds, new technologies, months of preparation and coaching, and some healthy pre-presentation jitters collide to reveal not only solid new business ideas, but also some promising entrepreneurial talent. In fact, professionals from around our region descend upon college campuses every spring to judge these events, which help to bridge the gap between academics and the real technology and business-driven economy.

  11. Additive Effects on Asymmetric Catalysis.

    PubMed

    Hong, Liang; Sun, Wangsheng; Yang, Dongxu; Li, Guofeng; Wang, Rui

    2016-03-23

    This review highlights a number of additives that can be used to make asymmetric reactions perfect. Without changing other reaction conditions, simply adding additives can lead to improved asymmetric catalysis, such as reduced reaction time, improved yield, or/and increased selectivity.

  12. Pyrophosphorolysis of CCA addition: implication for fidelity.

    PubMed

    Igarashi, Takao; Liu, Cuiping; Morinaga, Hironobu; Kim, Sangbumn; Hou, Ya-Ming

    2011-11-18

    In nucleic acid polymerization reaction, pyrophosphorolysis is the reversal of nucleotide addition, in which the terminal nucleotide is excised in the presence of inorganic pyrophosphate (PPi). The CCA enzymes are unusual RNA polymerases, which catalyze CCA addition to positions 74-76 at the tRNA 3' end without using a nucleic acid template. To better understand the reaction mechanism of CCA addition, we tested pyrophosphorolysis of CCA enzymes, which are divided into two structurally distinct classes. Here, we show that only class II CCA enzymes catalyze pyrophosphorolysis and that the reaction can initiate from all three CCA positions and proceed processively until the removal of nucleotide C74. Pyrophosphorolysis of class II enzymes establishes a fundamental difference from class I enzymes, and it is achieved only with the tRNA structure and with specific divalent metal ions. Importantly, pyrophosphorolysis enables class II enzymes to efficiently remove an incorrect A75 nucleotide from the 3' end, at a rate much faster than the rate of A75 incorporation, suggesting the ability to perform a previously unexpected quality control mechanism for CCA synthesis. Measurement of kinetic parameters of the class II Escherichia coli CCA enzyme reveals that the enzyme catalyzes pyrophosphorolysis slowly relative to the forward nucleotide addition and that it exhibits weak binding affinity to PPi relative to NTP, suggesting a mechanism in which PPi is rapidly released after each nucleotide addition as a driving force to promote the forward synthesis of CCA.

  13. Revealing power in truth

    PubMed Central

    Lee, Kelley

    2015-01-01

    Jeremy Shiffman’s editorial appropriately calls on making all forms of power more apparent and accountable, notably productive power derived from expertise and claims to moral authority. This commentary argues that relationships based on productive power can be especially difficult to reveal in global health policy because of embedded notions about the nature of power and politics. Yet, it is essential to recognize that global health is shot through with power relationships, that they can take many forms, and that their explicit acknowledgement should be part of, rather than factored out of, any reform of global health governance. PMID:25844390

  14. The Universe Revealed

    NASA Astrophysics Data System (ADS)

    Spence, Pam

    1998-10-01

    The Universe is a bewildering place to the uninitiated. The concepts and theories that govern space seem complex and often contradictory. The Universe Revealed provides the keys to unlocking the wonders of the cosmos. Elegantly written and lavishly illustrated, it begins with the Sun and stretches through our solar system into deepest space. Lucid prose, written by many of the people who have shaped our current thinking on space, and spectacular photographs make the physics of the Universe accessible and provide a solid background for understanding the most recent astronomical discoveries. Covering the most intriguing features of the cosmos, the topics discussed range from the Earth and global warming to cosmic collisions and the size of the Universe. Major sections examine the Solar System, stars, galaxies, cosmology, and the observational techniques used by astronomers, both amateur and professional. The Universe Revealed represents the collaboration of internationally renowned experts in astronomy and cosmology, with contributions from authors including David Malin, F. Duccio Macchetto, Iain Nicholson, Neil Bone, Ian Ridpath, Seth Shostak, Mike Lancaster, Steve Miller, Ken Croswell, Geoff McNamara, and Steven Young. This extraordinary blend of astronomy, astrophysics, and cosmology, will appeal to amateur and armchair astronomers alike.

  15. Multivariate sequence analysis reveals additional function impacting residues in the SDR superfamily.

    PubMed

    Tiwari, Pratibha; Singh, Noopur; Dixit, Aparna; Choudhury, Devapriya

    2014-10-01

    The "extended" type of short chain dehydrogenases/reductases (SDR), share a remarkable similarity in their tertiary structures inspite of being highly divergent in their functions and sequences. We have carried out principal component analysis (PCA) on structurally equivalent residue positions of 10 SDR families using information theoretic measures like Jensen-Shannon divergence and average shannon entropy as variables. The results classify residue positions in the SDR fold into six groups, one of which is characterized by low Shannon entropies but high Jensen-Shannon divergence against the reference family SDR1E, suggesting that these positions are responsible for the specific functional identities of individual SDR families, distinguishing them from the reference family SDR1E. Site directed mutagenesis of three residues from this group in the enzyme UDP-Galactose 4-epimerase belonging to SDR1E shows that the mutants promote the formation of NADH containing abortive complexes. Finally, molecular dynamics simulations have been used to suggest a mechanism by which the mutants interfere with the re-oxidation of NADH leading to the formation of abortive complexes.

  16. A study of vertebra number in pigs confirms the effect of vertnin and reveals additional QTL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Formation of the vertebral column is a critical developmental stage in mammals that is strictly controlled in most species. The pig is quite unique as considerable variation exists in number of thoracic vertebra as well as number of lumbar vertebra. At least two genes have been identified that affec...

  17. A study of vertebra number in pigs confirms the association of vertnin and reveals additional QTL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Formation of the vertebral column is a critical developmental stage in mammals. The strict control of this process has resulted in little variation in number of vertebrae across mammalian species and no variation within most mammalian species. The pig is quite unique as considerable vari...

  18. Random transposon mutagenesis of the Saccharopolyspora erythraea genome reveals additional genes influencing erythromycin biosynthesis

    PubMed Central

    Fedashchin, Andrij; Cernota, William H.; Gonzalez, Melissa C.; Leach, Benjamin I.; Kwan, Noelle; Wesley, Roy K.; Weber, J. Mark

    2015-01-01

    A single cycle of strain improvement was performed in Saccharopolyspora erythraea mutB and 15 genotypes influencing erythromycin production were found. Genotypes generated by transposon mutagenesis appeared in the screen at a frequency of ∼3%. Mutations affecting central metabolism and regulatory genes were found, as well as hydrolases, peptidases, glycosyl transferases and unknown genes. Only one mutant retained high erythromycin production when scaled-up from micro-agar plug fermentations to shake flasks. This mutant had a knockout of the cwh1 gene (SACE_1598), encoding a cell-wall-associated hydrolase. The cwh1 knockout produced visible growth and morphological defects on solid medium. This study demonstrated that random transposon mutagenesis uncovers strain improvement-related genes potentially useful for strain engineering. PMID:26468041

  19. CNV-based genome wide association study reveals additional variants contributing to meat quality in swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pork quality is important both to the meat processing industry and consumers’ purchasing attitudes. Copy number variation (CNV) is a burgeoning kind of variant that may influence meat quality. Herein, a genome-wide association study (GWAS) was performed between CNVs and meat quality traits in swine....

  20. Revealing the Beast Within

    NASA Astrophysics Data System (ADS)

    2003-07-01

    Deeply Embedded Massive Stellar Clusters Discovered in Milky Way Powerhouse Summary Peering into a giant molecular cloud in the Milky Way galaxy - known as W49 - astronomers from the European Southern Observatory (ESO) have discovered a whole new population of very massive newborn stars . This research is being presented today at the International Astronomical Union's 25th General Assembly held in Sydney, Australia, by ESO-scientist João Alves. With the help of infrared images obtained during a period of excellent observing conditions with the ESO 3.5-m New Technology Telescope (NTT) at the La Silla Observatory (Chile), the astronomers looked deep into this molecular cloud and discovered four massive stellar clusters, with hot and energetic stars as massive as 120 solar masses. The exceedingly strong radiation from the stars in the largest of these clusters is "powering" a 20 light-year diameter region of mostly ionized hydrogen gas (a "giant HII region"). W49 is one of the most energetic regions of star formation in the Milky Way. With the present discovery, the true sources of the enormous energy have now been revealed for the first time, finally bringing to an end some decades of astronomical speculations and hypotheses. PR Photo 21a/03 : Colour Composite of W49A (NTT+SOFI). PR Photo 21b/03 : Radio and Near-Infrared Composite of W49A Giant molecular clouds Stars form predominantly inside Giant Molecular Clouds which populate our Galaxy, the Milky Way. One of the most prominent of these is W49 , which has a mass of a million solar masses. It is located some 37,000 light-years away and is the most luminous star-forming region known in our home galaxy: its luminosity is several million times the luminosity of our Sun. A smaller region within this cloud is denoted W49A - this is one of the strongest radio-emitting areas known in the Galaxy . Massive stars are excessive in all ways. Compared to their smaller and ligther brethren, they form at an Olympic speed and

  1. Adverse reactions to drug additives.

    PubMed

    Simon, R A

    1984-10-01

    There is a long list of additives used by the pharmaceutical industry. Most of the agents used have not been implicated in hypersensitivity reactions. Among those that have, only reactions to parabens and sulfites have been well established. Parabens have been shown to be responsible for rare immunoglobulin E-mediated reactions that occur after the use of local anesthetics. Sulfites, which are present in many drugs, including agents commonly used to treat asthma, have been shown to provoke severe asthmatic attacks in sensitive individuals. Recent studies indicate that additives do not play a significant role in "hyperactivity." The role of additives in urticaria is not well established and therefore the incidence of adverse reactions in this patient population is simply not known. In double-blind, placebo-controlled studies, reactions to tartrazine or additives other than sulfites, if they occur at all, are indeed quite rare for the asthmatic population, even for the aspirin-sensitive subpopulation.

  2. Radiation Therapy: Additional Treatment Options

    MedlinePlus

    ... SNIPEND SNIPSTART Find A Radiation Oncologist SNIPEND Additional Treatment Options SNIPSTART A A SNIPEND Chemotherapy Medicines prescribed ... such as antibodies, to fight cancer. Novel Targeted Therapies Cancer doctors now know much more about how ...

  3. Calculators and Computers: Graphical Addition.

    ERIC Educational Resources Information Center

    Spero, Samuel W.

    1978-01-01

    A computer program is presented that generates problem sets involving sketching graphs of trigonometric functions using graphical addition. The students use calculators to sketch the graphs and a computer solution is used to check it. (MP)

  4. Food additives and preschool children.

    PubMed

    Martyn, Danika M; McNulty, Breige A; Nugent, Anne P; Gibney, Michael J

    2013-02-01

    Food additives have been used throughout history to perform specific functions in foods. A comprehensive framework of legislation is in place within Europe to control the use of additives in the food supply and ensure they pose no risk to human health. Further to this, exposure assessments are regularly carried out to monitor population intakes and verify that intakes are not above acceptable levels (acceptable daily intakes). Young children may have a higher dietary exposure to chemicals than adults due to a combination of rapid growth rates and distinct food intake patterns. For this reason, exposure assessments are particularly important in this age group. The paper will review the use of additives and exposure assessment methods and examine factors that affect dietary exposure by young children. One of the most widely investigated unfavourable health effects associated with food additive intake in preschool-aged children are suggested adverse behavioural effects. Research that has examined this relationship has reported a variety of responses, with many noting an increase in hyperactivity as reported by parents but not when assessed using objective examiners. This review has examined the experimental approaches used in such studies and suggests that efforts are needed to standardise objective methods of measuring behaviour in preschool children. Further to this, a more holistic approach to examining food additive intakes by preschool children is advisable, where overall exposure is considered rather than focusing solely on behavioural effects and possibly examining intakes of food additives other than food colours.

  5. Gusev's Rim Revealed

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit took this panoramic camera image on sol 91 (April 5, 2004). Spirit is looking to the southeast, and through the martian haze has captured the rim of Gusev Crater approximately 80 kilometers (49.7 miles) away on the horizon.

    The right side of this image reveals the portion of the crater edge that descends into the mouth of Ma'adim Vallis, a channel that opens into Gusev Crater. Spirit is currently traveling toward the informally named 'Columbia Hills,' which lie to the left of the region pictured here.

    This image is similar to a panoramic camera image taken on sol 68, but Gusev's ridge is more visible here because the atmospheric dust caused by winter dust storms has settled. Scientists expect to get even clearer images than this one in upcoming sols.

    This image has been modified to make the crater rim more visible.

  6. Ancient River revealed

    NASA Astrophysics Data System (ADS)

    Recent flights of the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) mission aboard the space shuttle Endeavour discovered a previously unknown branch of an ancient river. The images, released at AGU's Spring Meeting, show the river channel buried under thousands of years worth of windblown sand in a region of North Africa's Sahara Desert near the Kufra Oasis in southeast Libya, centered at 23.3°N latitude, 22.9°E longitude. The image from the flight last October reveals a system of old, now inactive stream valleys, called “paleodrainage systems,” which carried running water northward across the Sahara during periods of wetter climate.

  7. Addition of Polyadenylate Sequences to Virus-Specific RNA during Adenovirus Replication

    PubMed Central

    Philipson, L.; Wall, R.; Glickman, G.; Darnell, J. E.

    1971-01-01

    Adenovirus-specific nuclear and polysomal RNA, both early and late in the infectious cycle, contain a covalently linked region of polyadenylic acid 150-250 nucleotides long. A large proportion of the adenovirus-specific messenger RNA contains poly(A). As revealed by hybridization experiments, the poly(A) is not transcribed from adenovirus DNA. Furthermore, an adenosine analogue, cordycepin, blocks the synthesis of poly(A) and also inhibits the accumulation of adenovirus messenger RNA on polysomes. Addition of poly(A) to viral RNA may involve a host-controlled mechanism that regulates the processing and transport of messenger RNA. PMID:5315962

  8. Addition of polyadenylate sequences to virus-specific RNA during adenovirus replication.

    PubMed

    Philipson, L; Wall, R; Glickman, G; Darnell, J E

    1971-11-01

    Adenovirus-specific nuclear and polysomal RNA, both early and late in the infectious cycle, contain a covalently linked region of polyadenylic acid 150-250 nucleotides long. A large proportion of the adenovirus-specific messenger RNA contains poly(A). As revealed by hybridization experiments, the poly(A) is not transcribed from adenovirus DNA. Furthermore, an adenosine analogue, cordycepin, blocks the synthesis of poly(A) and also inhibits the accumulation of adenovirus messenger RNA on polysomes. Addition of poly(A) to viral RNA may involve a host-controlled mechanism that regulates the processing and transport of messenger RNA.

  9. The Role of Conceptual Understanding in Children's Addition Problem Solving.

    ERIC Educational Resources Information Center

    Canobi, Katherine H.; Reeve, Robert A.; Pattison, Philippa E.

    1998-01-01

    Examined the relationship between 6- to 8-year olds' conceptual understanding of additive composition, commutativity, and associativity principles and addition problem-solving procedures. Results revealed that conceptual understanding was related to using order-indifferent, decomposition, and retrieval strategies and speed and accuracy in solving…

  10. Evaluation of certain food additives.

    PubMed

    2015-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, and to prepare specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation of and assessment of dietary exposure to food additives, including flavouring agents. A summary follows of the Committee's evaluations of technical, toxicological and dietary exposure data for eight food additives (Benzoe tonkinensis; carrageenan; citric and fatty acid esters of glycerol; gardenia yellow; lutein esters from Tagetes erecta; octenyl succinic acid-modified gum arabic; octenyl succinic acid-modified starch; paprika extract; and pectin) and eight groups of flavouring agents (aliphatic and alicyclic hydrocarbons; aliphatic and aromatic ethers; ionones and structurally related substances; miscellaneous nitrogen-containing substances; monocyclic and bicyclic secondary alcohols, ketones and related esters; phenol and phenol derivatives; phenyl-substituted aliphatic alcohols and related aldehydes and esters; and sulfur-containing heterocyclic compounds). Specifications for the following food additives were revised: citric acid; gellan gum; polyoxyethylene (20) sorbitan monostearate; potassium aluminium silicate; and Quillaia extract (Type 2). Annexed to the report are tables summarizing the Committee's recommendations for dietary exposures to and toxicological evaluations of all of the food additives and flavouring agents considered at this meeting.

  11. [INVITED] Lasers in additive manufacturing

    NASA Astrophysics Data System (ADS)

    Pinkerton, Andrew J.

    2016-04-01

    Additive manufacturing is a topic of considerable ongoing interest, with forecasts predicting it to have major impact on industry in the future. This paper focusses on the current status and potential future development of the technology, with particular reference to the role of lasers within it. It begins by making clear the types and roles of lasers in the different categories of additive manufacturing. This is followed by concise reviews of the economic benefits and disadvantages of the technology, current state of the market and use of additive manufacturing in different industries. Details of these fields are referenced rather than expanded in detail. The paper continues, focusing on current indicators to the future of additive manufacturing. Barriers to its development, trends and opportunities in major industrial sectors, and wider opportunities for its development are covered. Evidence indicates that additive manufacturing may not become the dominant manufacturing technology in all industries, but represents an excellent opportunity for lasers to increase their influence in manufacturing as a whole.

  12. Additive manufacturing of hybrid circuits

    SciTech Connect

    Bell, Nelson S.; Sarobol, Pylin; Cook, Adam; Clem, Paul G.; Keicher, David M.; Hirschfeld, Deidre; Hall, Aaron Christopher

    2016-03-26

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects. Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. As a result, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.

  13. Children, Additive Change, and Calculus.

    ERIC Educational Resources Information Center

    Nemirovsky, Ricardo; And Others

    Students can learn to solve problems of qualitative integration and differentiation independently of their study of formal calculus or algebra. This exploratory study investigated the basic intuitions that elementary school children construct in their daily experience with physical and symbolic change. Elementary school children (n=18) were…

  14. Tougher Addition Polyimides Containing Siloxane

    NASA Technical Reports Server (NTRS)

    St. Clair, T. L.; Maudgal, S.

    1986-01-01

    Laminates show increased impact resistances and other desirable mechanical properties. Bismaleamic acid extended by reaction of diaminosiloxane with maleic anhydride in 1:1 molar ratio, followed by reaction with half this molar ratio of aromatic dianhydride. Bismaleamic acid also extended by reaction of diaminosiloxane with maleic anhydride in 1:2 molar ratio, followed by reaction with half this molar ratio of aromatic diamine (Michael-addition reaction). Impact resistances improved over those of unmodified bismaleimide, showing significant increase in toughness. Aromatic addition polyimides developed as both matrix and adhesive resins for applications on future aircraft and spacecraft.

  15. Intolerance to food additives - does it exist?

    PubMed

    Turner, Paul J; Kemp, Andrew S

    2012-02-01

    'Food intolerance' is often confused with a range of adverse symptoms which may be coincidental to ingestion of food. 'Food intolerance' is defined as a reaction in which symptoms must be objectively reproducible and not known to involve an immunological mechanism. A more precise term is non-allergic food hypersensitivity, which contrasts with food allergies which are due to an immunological mechanism. Some children will experience food reactions to food additives. Reported symptoms range from urticaria/angioedema to hyperactive behaviours. While parents/carers report that over one fifth of children experience of food reaction, only 1 in 20 of these are confirmed to have a non-allergic food hypersensitivity on testing.

  16. RADAR Reveals Titan Topography

    NASA Technical Reports Server (NTRS)

    Kirk, R. L.; Callahan, P.; Seu, R.; Lorenz, R. D.; Paganelli, F.; Lopes, R.; Elachi, C.

    2005-01-01

    The Cassini Titan RADAR Mapper is a K(sub u)-band (13.78 GHz, lambda = 2.17 cm) linear polarized RADAR instrument capable of operating in synthetic aperture (SAR), scatterometer, altimeter and radiometer modes. During the first targeted flyby of Titan on 26 October, 2004 (referred to as Ta) observations were made in all modes. Evidence for topographic relief based on the Ta altimetry and SAR data are presented here. Additional SAR and altimetry observations are planned for the T3 encounter on 15 February, 2005, but have not been carried out at this writing. Results from the T3 encounter relevant to topography will be included in our presentation. Data obtained in the Ta encounter include a SAR image swath

  17. The Additive Property of Energy.

    ERIC Educational Resources Information Center

    Tsaoussis, Dimitris S.

    1995-01-01

    Presents exercises that analyze the additive property of energy. Concludes that if a body has more than one component of energy depending on the same physical quantity, the body's total energy will be the algebraic sum of the components if a linear relationship exists between the energy components and that physical quantity. (JRH)

  18. Tetrasulfide extreme pressure lubricant additives

    SciTech Connect

    Gast, L.E.; Kenney, H.E.; Schwab, A.W.

    1980-08-19

    A novel class of compounds has been prepared comprising the tetrasulfides of /sup 18/C hydrocarbons, /sup 18/C fatty acids, and /sup 18/C fatty and alkyl and triglyceride esters. These tetrasulfides are useful as extreme pressure lubricant additives and show potential as replacements for sulfurized sperm whale oil.

  19. Out of bounds additive manufacturing

    SciTech Connect

    Holshouser, Chris; Newell, Clint; Palas, Sid; Love, Lonnie J.; Kunc, Vlastimil; Lind, Randall F.; Lloyd, Peter D.; Rowe, John C.; Blue, Craig A.; Duty, Chad E.; Peter, William H.; Dehoff, Ryan R.

    2013-03-01

    Lockheed Martin and Oak Ridge National Laboratory are working on an additive manufacturing system capable of manufacturing components measured not in terms of inches or feet, but multiple yards in all dimensions with the potential to manufacture parts that are completely unbounded in size.

  20. Asphalt and asphalt additives. Transportation research record

    SciTech Connect

    Not Available

    1992-01-01

    Contents: use of asphalt emulsions for in-place recycling: oregon experience; gap-graded cold asphalt concrete: benefits of polymer-modified asphalt cement and fibers; cold in-place recycling for rehabilitation and widening of low-volume flexible pavements in indiana; in situ cold recycling of bituminous pavements with polymer-modified high float emulsions; evaluation of new generation of antistripping additives; correlation between performance-related characteristics of asphalt cement and its physicochemical parameters using corbett's fractions and hpgc; reaction rates and hardening susceptibilities as determined from pressure oxygen vessel aging of asphalts; evaluation of aging characteristics of asphalts by using tfot and rtfot at different temperature levels; summary of asphalt additive performance at selected sites; relating asphalt absorption to properties of asphalt cement and aggregate; study of the effectiveness of styrene-butadiene rubber latex in hot mix asphalt mixes; stability of straight and polymer-modified asphalts.

  1. Evaluation of certain food additives.

    PubMed

    2012-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, with a view to concluding as to safety concerns and to preparing specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation of and assessment of dietary exposure to food additives, including flavouring agents. A summary follows of the Committee's evaluations of technical, toxicological and dietary exposure data for five food additives (magnesium dihydrogen diphosphate; mineral oil (medium and low viscosity) classes II and III; 3-phytase from Aspergillus niger expressed in Aspergillus niger; serine protease (chymotrypsin) from Nocardiopsis prasina expressed in Bacillus licheniformis; and serine protease (trypsin) from Fusarium oxysporum expressed in Fusarium venenatum) and 16 groups of flavouring agents (aliphatic and aromatic amines and amides; aliphatic and aromatic ethers; aliphatic hydrocarbons, alcohols, aldehydes, ketones, carboxylic acids and related esters, sulfides, disulfides and ethers containing furan substitution; aliphatic linear alpha,beta-unsaturated aldehydes, acids and related alcohols, acetals and esters; amino acids and related substances; epoxides; furfuryl alcohol and related substances; linear and branched-chain aliphatic, unsaturated, unconjugated alcohols, aldehydes, acids and related esters; miscellaneous nitrogen-containing substances; phenol and phenol derivatives; pyrazine derivatives; pyridine, pyrrole and quinoline derivatives; saturated aliphatic acyclic branched-chain primary alcohols, aldehydes and acids; simple aliphatic and aromatic sulfides and thiols; sulfur-containing heterocyclic compounds; and sulfur-substituted furan derivatives). Specifications for the following food additives were revised: ethyl cellulose, mineral oil (medium viscosity), modified starches and titanium

  2. Vortices revealed: Swimming faster

    NASA Astrophysics Data System (ADS)

    van Houwelingen, Josje; van de Water, Willem; Kunnen, Rudie; van Heijst, Gertjan; Clercx, Herman

    2016-11-01

    Understanding and optimizing the propulsion in human swimming requires insight into the hydrodynamics of the flow around the swimmer. Experiments and simulations addressing the hydrodynamics of swimming have been conducted in studies before, including the visualization of the flow using particle image velocimetry (PIV). The main objective in this study is to develop a system to visualize the flow around a swimmer in practice inspired by this technique. The setup is placed in a regular swimming pool. The use of tracer particles and lasers to illuminate the particles is not allowed. Therefore, we choose to work with air bubbles with a diameter of 4 mm, illuminated by ambient light. Homogeneous bubble curtains are produced by tubes implemented in the bottom of the pool. The bubble motion is captured by six cameras placed in underwater casings. A first test with the setup has been conducted by pulling a cylinder through the bubbles and performing a PIV analysis. The vorticity plots of the resulting data show the expected vortex street behind the cylinder. The shedding frequency of the vortices resembles the expected frequency. Thus, it is possible to identify and follow the coherent structures. We will discuss these results and the first flow measurements around swimmers.

  3. The Frontiers of Additive Manufacturing

    SciTech Connect

    Grote, Christopher John

    2016-03-03

    Additive manufacturing, more commonly known as 3-D printing, has become a ubiquitous tool in science for its precise control over mechanical design. For additive manufacturing to work, a 3-D structure is split into thin 2D slices, and then different physical properties, such as photo-polymerization or melting, are used to grow the sequential layers. The level of control allows not only for devices to be made with a variety of materials: e.g. plastics, metals, and quantum dots, but to also have finely controlled structures leading to other novel properties. While 3-D printing is widely used by hobbyists for making models, it also has industrial applications in structural engineering, biological tissue scaffolding, customized electric circuitry, fuel cells, security, and more.

  4. Decontamination formulation with sorbent additive

    DOEpatents

    Tucker; Mark D. , Comstock; Robert H.

    2007-10-16

    A decontamination formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a bleaching activator, a sorbent additive, and water. The highly adsorbent, water-soluble sorbent additive (e.g., sorbitol or mannitol) is used to "dry out" one or more liquid ingredients, such as the liquid bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate) and convert the activator into a dry, free-flowing powder that has an extended shelf life, and is more convenient to handle and mix in the field.

  5. Additive Manufacturing Integrated Energy Demonstration

    SciTech Connect

    Jackson, Roderick; Lee, Brian; Love, Lonnie; Mabe, Gavin; Keller, Martin; Curran, Scott; Chinthavali, Madhu; Green, Johney; Sawyer, Karma; Enquist, Phil

    2016-02-05

    Meet AMIE - the Additive Manufacturing Integrated Energy demonstration project. Led by Oak Ridge National Laboratory and many industry partners, the AMIE project changes the way we think about generating, storing, and using electrical power. AMIE uses an integrated energy system that shares energy between a building and a vehicle. And, utilizing advanced manufacturing and rapid innovation, it only took one year from concept to launch.

  6. Robust stability under additive perturbations

    NASA Technical Reports Server (NTRS)

    Bhaya, A.; Desoer, C. A.

    1985-01-01

    A MIMO linear time-invariant feedback system 1S(P,C) is considered which is assumed to be U-stable. The plant P is subjected to an additive perturbation Delta P which is proper but not necessarily stable. It is proved that the perturbed system is U-stable if and only if Delta P(I + Q x Delta P) exp -1 is U-stable.

  7. Additive Manufacturing Integrated Energy Demonstration

    ScienceCinema

    Jackson, Roderick; Lee, Brian; Love, Lonnie; Mabe, Gavin; Keller, Martin; Curran, Scott; Chinthavali, Madhu; Green, Johney; Sawyer, Karma; Enquist, Phil

    2016-07-12

    Meet AMIE - the Additive Manufacturing Integrated Energy demonstration project. Led by Oak Ridge National Laboratory and many industry partners, the AMIE project changes the way we think about generating, storing, and using electrical power. AMIE uses an integrated energy system that shares energy between a building and a vehicle. And, utilizing advanced manufacturing and rapid innovation, it only took one year from concept to launch.

  8. Nanoengineered Additives for Active Coatings

    DTIC Science & Technology

    2007-04-01

    commercial ad bial activ component from the coating, leading to eventual depletion of the film. Small TPU samples were evaluated using a Kirby - Bauer ...7 Table 5. Summary of 24-hr ASTM E 2180 tests with 1 weight-percent additive in PUr (solvent dispersible) based on 6-log loading of...Noveon X-1150). The ASTM E 2180 test is run in triplicate (Note that alternative ro 1° amines) was suspended in dry tetrahydrofuran (THF) (150 mL) in

  9. Reversible Oxidative Addition at Carbon.

    PubMed

    Eichhorn, Antonius F; Fuchs, Sonja; Flock, Marco; Marder, Todd B; Radius, Udo

    2017-04-07

    The reactivity of N-heterocyclic carbenes (NHCs) and cyclic alkyl amino carbenes (cAACs) with arylboronate esters is reported. The reaction with NHCs leads to the reversible formation of thermally stable Lewis acid/base adducts Ar-B(OR)2 ⋅NHC (Add1-Add6). Addition of cAAC(Me) to the catecholboronate esters 4-R-C6 H4 -Bcat (R=Me, OMe) also afforded the adducts 4-R-C6 H4 Bcat⋅cAAC(Me) (Add7, R=Me and Add8, R=OMe), which react further at room temperature to give the cAAC(Me) ring-expanded products RER1 and RER2. The boronate esters Ar-B(OR)2 of pinacol, neopentylglycol, and ethyleneglycol react with cAAC at RT via reversible B-C oxidative addition to the carbene carbon atom to afford cAAC(Me) (B{OR}2 )(Ar) (BCA1-BCA6). NMR studies of cAAC(Me) (Bneop)(4-Me-C6 H4 ) (BCA4) demonstrate the reversible nature of this oxidative addition process.

  10. Additive manufacturing of hybrid circuits

    DOE PAGES

    Bell, Nelson S.; Sarobol, Pylin; Cook, Adam; ...

    2016-03-26

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects.more » Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. As a result, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.« less

  11. Fire-Retardant Polymeric Additives

    NASA Technical Reports Server (NTRS)

    Williams, Martha K.; Smith, Trent M.

    2011-01-01

    Polyhydroxyamide (PHA) and polymethoxyamide (PMeOA) are fire-retardant (FR) thermoplastic polymers and have been found to be useful as an additive for imparting fire retardant properties to other compatible, thermoplastic polymers (including some elastomers). Examples of compatible flammable polymers include nylons, polyesters, and acrylics. Unlike most prior additives, PHA and PMeOA do not appreciably degrade the mechanical properties of the matrix polymer; indeed, in some cases, mechanical properties are enhanced. Also, unlike some prior additives, PHA and PMeOA do not decompose into large amounts of corrosive or toxic compounds during combustion and can be processed at elevated temperatures. PMeOA derivative formulations were synthesized and used as an FR additive in the fabrication of polyamide (PA) and polystyrene (PS) composites with notable reduction (>30 percent for PS) in peak heat release rates compared to the neat polymer as measured by a Cone Calorimeter (ASTM E1354). Synergistic effects were noted with nanosilica composites. These nanosilica composites had more than 50-percent reduction in peak heat release rates. In a typical application, a flammable thermoplastic, thermoplastic blend, or elastomer that one seeks to render flame-retardant is first dry-mixed with PHA or PMeOA or derivative thereof. The proportion of PHA or PMeOA or derivative in the mixture is typically chosen to lie between 1 and 20 weight percent. The dry blend can then be melt-extruded. The extruded polymer blend can further be extruded and/or molded into fibers, pipes, or any other of a variety of objects that may be required to be fire-retardant. The physical and chemical mechanisms which impart flame retardancy of the additive include inhibiting free-radical oxidation in the vapor phase, preventing vaporization of fuel (the polymer), and cooling through the formation of chemical bonds in either the vapor or the condensed phase. Under thermal stress, the cyclic hydroxyl/ methoxy

  12. Evaluation of certain food additives.

    PubMed

    2009-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessment of intake of food additives (in particular, flavouring agents). A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives (asparaginase from Aspergillus niger expressed in A. niger, calcium lignosulfonate (40-65), ethyl lauroyl arginate, paprika extract, phospholipase C expressed in Pichia pastoris, phytosterols, phytostanols and their esters, polydimethylsiloxane, steviol glycosides and sulfites [assessment of dietary exposure]) and 10 groups of related flavouring agents (aliphatic branched-chain saturated and unsaturated alcohols, aldehydes, acids and related esters; aliphatic linear alpha,beta-unsaturated aldehydes, acids and related alcohols, acetals and esters; aliphatic secondary alcohols, ketones and related esters; alkoxy-substituted allylbenzenes present in foods and essential oils and used as flavouring agents; esters of aliphatic acyclic primary alcohols with aliphatic linear saturated carboxylic acids; furan-substituted aliphatic hydrocarbons, alcohols, aldehydes, ketones, carboxylic acids and related esters, sulfides, disulfides and ethers; miscellaneous nitrogen-containing substances; monocyclic and bicyclic secondary alcohols, ketones and related esters; hydroxy- and alkoxy-substituted benzyl derivatives; and substances structurally related to menthol). Specifications for the following food additives were revised: canthaxanthin; carob bean gum and carob bean gum (clarified); chlorophyllin copper complexes, sodium and potassium salts; Fast Green FCF; guar gum and guar gum (clarified

  13. Limits of control: the effects of uncontrollability experiences on the efficiency of attentional control.

    PubMed

    Bukowski, Marcin; Asanowicz, Dariusz; Marzecová, Anna; Lupiáñez, Juan

    2015-01-01

    Two experiments were conducted to explore the effects of experiencing uncontrollability on the efficiency of attentional control. The experience of uncontrollability was induced either by unsolvable tasks (Experiment 1) or by tasks in which non-contingent feedback was provided (Experiment 2). A version of the Attentional Network Test-Interactions with an additional measure of vigilance (ANTI-V) was used to evaluate the efficiency of the attentional networks (i.e., alerting, orienting, and executive). Results of both experiments revealed a decreased efficiency of executive attention in participants who experienced stable control deprivation but no negative effects in participants who were able to restore their sense of previously deprived control. Additionally, when participants were asked to perform unsolvable tasks and did not receive feedback (Experiment 1), detrimental effects on the orienting network and vigilance were observed. The motivational and cognitive mechanisms underlying the effects of various uncontrollability experiences on conflict resolution and attentional control are discussed.

  14. Industrial application experiment series

    NASA Technical Reports Server (NTRS)

    Bluhm, S. A.

    1980-01-01

    The deployment of parabolic dish systems into the industrial sector for the purpose of providing users, suppliers, sponsors, and developers with a realistic assessment of system feasibility in selected near-term industrial applications will be accomplished initially through the industrial module experiment and later through additional experiments involving thermal, electric, and combined thermal and electrical systems. The approach is to progress through steps, from single module to multi-module systems, from thermal-only applications to more complex combined thermal and electric applications. The experience of other solar thermal experiments, particularly those involving parabolic dish hardware, will be utilized to the fullest extent possible in experiment planning and implementation.

  15. Effect of surfactant addition on phenanthrene biodegradation in sediments

    SciTech Connect

    Tsomides, H.J.; Hughes, J.B.; Thomas, J.M.; Ward, C.H.

    1995-12-31

    A laboratory study was conducted to determine whether commercial surfactants enhance the bioremediation of PAH-contaminated sediments. Phenanthrene was chosen as a representative PAH. An inoculum of PAH-degrading microorganisms, enriched from an aquatic sediment, was used in sediment-water slurry microcosm biodegradation experiments. Of seven nonionic surfactants tested, only one (Triton X-100) did not inhibit phenanthrene mineralization at concentrations above the critical micelle concentration (CMC). Temporal studies on Triton X-100 revealed that while it initially inhibited mineralization in sediment-free microcosms, after 1 week Triton X-100 slightly improved phenanthrene biotransformation and mineralization in microcosms with and without sediment. For all treatments, phenanthrene disappearance was complete after 9 d. and mineralization reached 50 to 65% after 12 d. Sorption to the sediment appears to have reduced the free aqueous surfactant concentration, thereby reducing surfactant toxicity to the microorganisms. These results suggest that many surfactants are toxic to PAH-degrading microorganisms, and while surfactant addition may not always have adverse effects on biodegradation, the use of surfactants might not be necessary to achieve complete contaminant removal.

  16. Effect of surfactant addition on phenanthrene biodegradation in sediments

    SciTech Connect

    Tsomides, H.J.; Hughes, J.B.; Thomas, J.M.; Ward, C.H.

    1995-06-01

    A laboratory study was conducted to determine whether commercial surfactants enhance the bioremediation of PAH-contaminated sediments. Phenanthrene was chosen as a representative PAH; an inoculum of PAH-degrading microorganisms, enriched from an aquatic sediment, was used in sediment-water slurry microcosm biodegradation experiments. Of seven non-ionic surfactants tested, only one (Triton X-100) did not inhibit phenanthrene mineralization at concentrations above the critical micelle concentration (CMC). Temporal studies on Triton X-100 revealed that while it initially inhibited mineralization in sediment-free microcosms, after 1 week Triton X-100 slightly improved phenanthrene biotransformation and mineralization in microcosms with and without sediment. For all treatments, phenanthrene disappearance was complete after 9 d, and mineralization reached 50 to 65% after 12 d. Sorption to the sediment appears to have reduced the free aqueous surfactant concentration, thereby reducing surfactant toxicity to the microorganisms. These results suggest that many surfactants are toxic to PAH-degrading microorganisms, and while surfactant addition may not always have adverse effects on biodegradation, the use of surfactants might not be desirable to achieve complete contamination removal.

  17. The Mozart Effect: Additional Data.

    PubMed

    Hughes, John R.

    2002-04-01

    After the review of the Mozart effect was published in this journal (Hughes JR. Epilepsy Behav 2001;2:369-417), additional data from the music of Haydn and Liszt have been analyzed that may account for the decrease in seizure activity originally reported during Mozart music. Even with these added data Mozart music continued to score significantly higher than the selections from the other six composers in one of the important characteristics of this music, namely, the repetition of the melody. However Haydn's values were second highest among Mozart, J. S. Bach, Wagner, Beethoven, Chopin, and Liszt.

  18. Water based drilling mud additive

    SciTech Connect

    McCrary, J.L.

    1983-12-13

    A water based fluid additive useful in drilling mud used during drilling of an oil or gas well is disclosed, produced by reacting water at temperatures between 210/sup 0/-280/sup 0/ F. with a mixture comprising in percent by weight: gilsonite 25-30%, tannin 7-15%, lignite 25-35%, sulfonating compound 15-25%, water soluble base compound 5-15%, methylene-yielding compound 1-5%, and then removing substantially all of the remaining water to produce a dried product.

  19. Metal Additive Manufacturing: A Review

    NASA Astrophysics Data System (ADS)

    Frazier, William E.

    2014-06-01

    This paper reviews the state-of-the-art of an important, rapidly emerging, manufacturing technology that is alternatively called additive manufacturing (AM), direct digital manufacturing, free form fabrication, or 3D printing, etc. A broad contextual overview of metallic AM is provided. AM has the potential to revolutionize the global parts manufacturing and logistics landscape. It enables distributed manufacturing and the productions of parts-on-demand while offering the potential to reduce cost, energy consumption, and carbon footprint. This paper explores the material science, processes, and business consideration associated with achieving these performance gains. It is concluded that a paradigm shift is required in order to fully exploit AM potential.

  20. Theatre fleet's vital additional capacity.

    PubMed

    2012-11-01

    Vanguard Healthcare's fleet of mobile surgical facilities has been deployed to healthcare sites throughout Europe and beyond for over a decade, providing vital additional clinical capacity when existing buildings are refurbished or upgraded, in the event of flood or fire, or simply to help hospitals cater for rising demand. It is a combination of careful planning, teamwork, and the specialist expertise of Vanguard's personnel--many with a clinical background--that ensures not only each unit's successful installation, but equally its subsequent running, servicing, and maintenance, the company explains.

  1. Shale JP-4 Additive Evaluation

    DTIC Science & Technology

    1986-10-01

    8217. •% . , ’ ,,,r ,% . -- - ,.-. ’ ’ 4,w% %’. " - ,’ . . . * ’, .* . TABLE OF CONTENTS .4q ,4 . * SECTION PAGE I. INTRODUCTION 1 II. TEST PARAMETERS 2 1...42 PRECEDING PAGE BLANK TABLE OF CONTENTS (CON’T) SECT ION PAGE V. CONCLUSIONS 44 REFERENCES 46 APPENDIX A Drum to Test Sample Relationship 47 APPENDIX...B.O.C.L.E. Results 40 vii LIST OF TABLES TABLE PAGE 1 Antioxidants 3 2 Raw Shale/Petroleum Fuel Properties 10 3 Drum Sample Additive Content 13 4

  2. Additionality of global benefits and financial additionality in the context of the AIJ negotiations

    SciTech Connect

    Puhl, I.

    1996-12-31

    The Conference of the Party at their first meeting (COP1) took a decision regarding criteria for joint implementation as indicated in Art. 4.2 (a) of the FCCC which established a pilot phase for activities implemented jointly (AIJ) under the pilot phase. Besides some more technical issues this decision specified that such measures should bring about real, measurable and long-term environmental benefits related to the mitigation of climate change that would not have occurred in the absence of such activities. It also established that the financing of AIJ shall be additional to the financial obligations of developed country parties. These two requirements are called the additionality criteria for AIJ. The first refers to the realness of GHG emission abatement (which means reduction compared to a baseline) whereas the second describes that funds earmarked for AIJ have no other objective (i.e. profit making, export promotion) but to reduce GHG emissions to avoid the free-riding of investors and subsequently developed country parties. The reporting framework as well as the reporting requirements under national programs do not specify further the two types of additionality and even though research focuses on issues like baseline determination there has been no attempt so far to identify approaches which contribute towards defining strict and practicable methods and guidelines to frame additionality criteria. The first FCCC assessment of pilot project reporting revealed that in the reporting of activities, emissions additionality often remained unclear, especially in cases where AIJ was only a portion of an existing or already planned project, and that there is a point about how to account for financial additionality. It subsequently proposed to develop a uniform approach to baseline determination and the assessment of emission (reduction) additionality and financial additionality.

  3. Additional stories of microRNAs.

    PubMed

    Lee, Heon-Jin

    2014-10-01

    MicroRNAs (miRNAs) have been shown to be major regulators of eukaryotic gene expression. Traditionally, miRNAs were thought to control highly complex signal transduction and other biological pathways by targeting coding transcripts, accounting for their important role in cellular events. Traditional miRNA biogenesis and function focused on several key enzymes that functioned in miRNA maturation and miRNA inhibitory function upon binding to 3'-untranslated region of target transcripts. However, recent studies have revealed that miRNA biosynthesis and function is complicated, with many exceptions to conventional miRNA mechanisms. In addition to those noncanonical miRNA functions, this review introduces newly discovered biogenesis and regulatory mechanisms, as well as a new class of miRNA-sized small RNA and miRNA methylation. miRNA inhibition and intercellular miRNA signaling are also discussed. Taken together, these insights extend current understanding of miRNAs.

  4. Titan Casts Revealing Shadow

    NASA Astrophysics Data System (ADS)

    2004-05-01

    A rare celestial event was captured by NASA's Chandra X-ray Observatory as Titan -- Saturn's largest moon and the only moon in the Solar System with a thick atmosphere -- crossed in front of the X-ray bright Crab Nebula. The X-ray shadow cast by Titan allowed astronomers to make the first X-ray measurement of the extent of its atmosphere. On January 5, 2003, Titan transited the Crab Nebula, the remnant of a supernova explosion that was observed to occur in the year 1054. Although Saturn and Titan pass within a few degrees of the Crab Nebula every 30 years, they rarely pass directly in front of it. "This may have been the first transit of the Crab Nebula by Titan since the birth of the Crab Nebula," said Koji Mori of Pennsylvania State University in University Park, and lead author on an Astrophysical Journal paper describing these results. "The next similar conjunction will take place in the year 2267, so this was truly a once in a lifetime event." Animation of Titan's Shadow on Crab Nebula Animation of Titan's Shadow on Crab Nebula Chandra's observation revealed that the diameter of the X-ray shadow cast by Titan was larger than the diameter of its solid surface. The difference in diameters gives a measurement of about 550 miles (880 kilometers) for the height of the X-ray absorbing region of Titan's atmosphere. The extent of the upper atmosphere is consistent with, or slightly (10-15%) larger, than that implied by Voyager I observations made at radio, infrared, and ultraviolet wavelengths in 1980. "Saturn was about 5% closer to the Sun in 2003, so increased solar heating of Titan may account for some of this atmospheric expansion," said Hiroshi Tsunemi of Osaka University in Japan, one of the coauthors on the paper. The X-ray brightness and extent of the Crab Nebula made it possible to study the tiny X-ray shadow cast by Titan during its transit. By using Chandra to precisely track Titan's position, astronomers were able to measure a shadow one arcsecond in

  5. High Flow Addition Curing Polyimides

    NASA Technical Reports Server (NTRS)

    Chuang, Kathy C.; Vannucci, Raymond D.; Ansari, Irfan; Cerny, Lawrence L.; Scheiman, Daniel A.

    1994-01-01

    A new series of high flow PMR-type addition curing polyimides was developed, which employed the substitution of 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (BTDB) for p-phenylenediamine (p -PDA) in a PMR-IL formulation. These thermoset polyimides, designated as 12F resins, were prepared from BTDB and the dimethyl ester of 4,4'- (hexafluo- roisopropylidene) -diphthalic acid (HFDE) with either nadic ester (NE) or p-aminostyrene (PAS) as the endcaps for addition curing. The 12F prepolymers displayed lower melting temperatures in DSC analysis, and higher melt flow in rheological studies than the cor- responding PMR-11 polyimides. Long-term isothermal aging studies showed that BTDB- based 12F resins exhibited comparable thermo-oxidative stability to P-PDA based PMR-11 polyimides. The noncoplanar 2- and 2'-disubstituted biphenyldiamine (BTDB) not only lowered the melt viscosities of 12F prepolymers, but also retained reasonable thermal sta- bility of the cured resins. The 12F polyimide resin with p-aminostyrene endcaps showed the best promise for long-term, high-temperature application at 343 C (650 F).

  6. Fuel Additives: Canada bans MMT

    SciTech Connect

    Sissell, K.

    1997-04-16

    The Canadian Senate voted late last week to ban use of the manganese-based fuel additive MMT, produced only in the US by Ethyl. MMT, which has been sold in Canada for the past 20 years and accounts for about half of Ethyl`s Canadian sales, has been criticized by environmentalists, who have raised public health concerns, and automakers, who say it harms emission control systems. {open_quotes}Canada`s vote is a great victory for public health and the environment,{close_quotes} says Environmental Defense Fund executive director Fred Krupp. {open_quotes}The US should move swiftly to follow suit and suspend sales of MMT until adequate toxicity testing on the additive is completed.{close_quotes} EPA had refused to approve MMT for sale because of health concerns but was compelled to do so by a December 1995 court ruling. Ethyl asserts the ban violates Canada`s obligations under Nafta and says it will file a damage claim with the Nafta arbitration panel.

  7. Additive interaction between heterogeneous environmental ...

    EPA Pesticide Factsheets

    BACKGROUND Environmental exposures often occur in tandem; however, epidemiological research often focuses on singular exposures. Statistical interactions among broad, well-characterized environmental domains have not yet been evaluated in association with health. We address this gap by conducting a county-level cross-sectional analysis of interactions between Environmental Quality Index (EQI) domain indices on preterm birth in the Unites States from 2000-2005.METHODS: The EQI, a county-level index constructed for the 2000-2005 time period, was constructed from five domain-specific indices (air, water, land, built and sociodemographic) using principal component analyses. County-level preterm birth rates (n=3141) were estimated using live births from the National Center for Health Statistics. Linear regression was used to estimate prevalence differences (PD) and 95% confidence intervals (CI) comparing worse environmental quality to the better quality for each model for a) each individual domain main effect b) the interaction contrast and c) the two main effects plus interaction effect (i.e. the “net effect”) to show departure from additive interaction for the all U.S counties. Analyses were also performed for subgroupings by four urban/rural strata. RESULTS: We found the suggestion of antagonistic interactions but no synergism, along with several purely additive (i.e., no interaction) associations. In the non-stratified model, we observed antagonistic interac

  8. Additive manufacturing of RF absorbers

    NASA Astrophysics Data System (ADS)

    Mills, Matthew S.

    The ability of additive manufacturing techniques to fabricate integrated electromagnetic absorbers tuned for specific radio frequency bands within structural composites allows for unique combinations of mechanical and electromagnetic properties. These composites and films can be used for RF shielding of sensitive electromagnetic components through in-plane and out-of-plane RF absorption. Structural composites are a common building block of many commercial platforms. These platforms may be placed in situations in which there is a need for embedded RF absorbing properties along with structural properties. Instead of adding radar absorbing treatments to the external surface of existing structures, which adds increased size, weight and cost; it could prove to be advantageous to integrate the microwave absorbing properties directly into the composite during the fabrication process. In this thesis, a method based on additive manufacturing techniques of composites structures with prescribed electromagnetic loss, within the frequency range 1 to 26GHz, is presented. This method utilizes screen printing and nScrypt micro dispensing to pattern a carbon based ink onto low loss substrates. The materials chosen for this study will be presented, and the fabrication technique that these materials went through to create RF absorbing structures will be described. The calibration methods used, the modeling of the RF structures, and the applications in which this technology can be utilized will also be presented.

  9. Microgravity Experiments On Animals

    NASA Technical Reports Server (NTRS)

    Dalton, B. P.; Leon, H.; Hogan, R.; Clarke, B.; Tollinger, D.

    1991-01-01

    Paper describes experiments on animal subjects planned for Spacelab Life Sciences 1 mission. Laboratory equipment evaluated, and physiological experiments performed. Represents first step in establishing technology for maintaining and manipulating rodents, nonhuman primates, amphibians, and plants during space flight without jeopardizing crew's environment. In addition, experiments focus on effects of microgravity on cardiopulmonary, cardiovascular, and musculoskeletal systems; on regulation of volume of blood and production of red blood cells; and on calcium metabolism and gravity receptors.

  10. Bubble formation in additive manufacturing of glass

    NASA Astrophysics Data System (ADS)

    Luo, Junjie; Gilbert, Luke J.; Peters, Daniel C.; Bristow, Douglas A.; Landers, Robert G.; Goldstein, Jonathan T.; Urbas, Augustine M.; Kinzel, Edward C.

    2016-05-01

    Bubble formation is a common problem in glass manufacturing. The spatial density of bubbles in a piece of glass is a key limiting factor to the optical quality of the glass. Bubble formation is also a common problem in additive manufacturing, leading to anisotropic material properties. In glass Additive Manufacturing (AM) two separate types of bubbles have been observed: a foam layer caused by the reboil of the glass melt and a periodic pattern of bubbles which appears to be unique to glass additive manufacturing. This paper presents a series of studies to relate the periodicity of bubble formation to part scan speed, laser power, and filament feed rate. These experiments suggest that bubbles are formed by the reboil phenomena why periodic bubbles result from air being trapped between the glass filament and the substrate. Reboil can be detected using spectroscopy and avoided by minimizing the laser power while periodic bubbles can be avoided by a two-step laser melting process to first establish good contact between the filament and substrate before reflowing the track with higher laser power.

  11. 21 CFR 170.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... AND HUMAN SERVICES (CONTINUED) FOOD ADDITIVES Food Additive Safety § 170.20 General principles for...) Upon written request describing the proposed use of an additive and the proposed experiments to... additive whether he believes the experiments planned will yield data adequate for an evaluation of...

  12. APEX reveals glowing stellar nurseries

    NASA Astrophysics Data System (ADS)

    2008-11-01

    Illustrating the power of submillimetre-wavelength astronomy, an APEX image reveals how an expanding bubble of ionised gas about ten light-years across is causing the surrounding material to collapse into dense clumps that are the birthplaces of new stars. Submillimetre light is the key to revealing some of the coldest material in the Universe, such as these cold, dense clouds. Glowing Stellar Nurseries ESO PR Photo 40/08 Glowing Stellar Nurseries The region, called RCW120, is about 4200 light years from Earth, towards the constellation of Scorpius. A hot, massive star in its centre is emitting huge amounts of ultraviolet radiation, which ionises the surrounding gas, stripping the electrons from hydrogen atoms and producing the characteristic red glow of so-called H-alpha emission. As this ionised region expands into space, the associated shock wave sweeps up a layer of the surrounding cold interstellar gas and cosmic dust. This layer becomes unstable and collapses under its own gravity into dense clumps, forming cold, dense clouds of hydrogen where new stars are born. However, as the clouds are still very cold, with temperatures of around -250˚ Celsius, their faint heat glow can only be seen at submillimetre wavelengths. Submillimetre light is therefore vital in studying the earliest stages of the birth and life of stars. The submillimetre-wavelength data were taken with the LABOCA camera on the 12-m Atacama Pathfinder Experiment (APEX) telescope, located on the 5000 m high plateau of Chajnantor in the Chilean Atacama desert. Thanks to LABOCA's high sensitivity, astronomers were able to detect clumps of cold gas four times fainter than previously possible. Since the brightness of the clumps is a measure of their mass, this also means that astronomers can now study the formation of less massive stars than they could before. The plateau of Chajnantor is also where ESO, together with international partners, is building a next generation submillimetre telescope, ALMA

  13. Additives in fibers and fabrics.

    PubMed Central

    Barker, R H

    1975-01-01

    The additives and contaminants which occur in textile fibers vary widely, depending on the type of fiber and the pretreatment which it has received. Synthetic fibers such as nylon and polyester contain trace amounts of contaminants such as catalysts and catalyst deactivators which remain after the synthesis of the basic polymers. In addition, there are frequently a number of materials which are added to perform specific functions in almost all man-made fibers. Examples of these would include traces of metals or metal salts used as tracers for identification of specific lots of fiber, TiO2 or similar materials added as delustrants, and a host of organic species added for such special purposes as antistatic agents or flame retardants. There may also be considerable quantities of residual monomer or small oligomers dissolved in the polymer matrix. The situation becomes even more complex after the fibers are converted into fabric form. Numerous materials are applied at various stages of fabric preparation to act as lubricants, sizing agents, antistats, bleaches, and wetting agents to facilitate the processing, but these are normally removed before the fabric reaches the cutters of the ultimate consumers and therefore usually do not constitute potential hazards. However, there are many other chemical agents which are frequently added during the later stages of fabric preparation and which are not designed to be removed. Aside from dyes and printing pigments, the most common additive for apparel fabrics is a durable press treatment. This generally involves the use of materials capable of crosslinking cellulosics by reacting through such functions as N-methylolated amides or related compounds such as ureas and carbamates. These materials pose some potential hazards due to both the nitrogenous bases and the formaldehyde which they usually release. There is usually also some residual catalyst in fabrics which have received such treatments. Other types of chemical treatments

  14. Amine-intercalated α-zirconium phosphates as lubricant additives

    NASA Astrophysics Data System (ADS)

    Xiao, Huaping; Dai, Wei; Kan, Yuwei; Clearfield, Abraham; Liang, Hong

    2015-02-01

    In this study, three types of amines intercalated α-zirconium phosphate nanosheets with different interspaces were synthesized and examined as lubricant additives to a mineral oil. Results from tribological experiments illustrated that these additives improved lubricating performance. Results of rheological experiments showed that the viscosity of the mineral oil was effectively reduced with the addition of α-zirconium phosphate nanosheets. The two-dimensional structure, with larger interspaces, resulting from amine intercalation, exhibited improved effectiveness in reducing viscosity. This study demonstrates that the nanosheet structure of α-zirconium phosphates is effective in friction reduction. The manufacture of lubricants with tailored viscosity is possible by using different intercalators.

  15. Optics of progressive addition lenses.

    PubMed

    Sheedy, J E; Buri, M; Bailey, I L; Azus, J; Borish, I M

    1987-02-01

    The optical characteristics of the major progressive addition lenses were measured using an automated lensometer with a specially designed lens holder to simulate eye rotation. Measurements were made every 3 degrees (about 1.5 mm) and graphs of isospherical equivalent lines and isocylinder lines were developed. Generally the near zone of these lenses is narrower and lower than in bifocal or trifocal lenses. Distinct differences exist between the various progressive lenses. The width of the near zone, rate of power progression, amount of unwanted cylinder (level with the distance center), and clarity of the distance zone are compared for the various lenses. The optical measurements demonstrate an apparent trade-off between the size of the cylinder-free area of the lens and the amount of the cylinder.

  16. Interactive responses of grass litter decomposition to warming, nitrogen addition and detritivore access in a temperate old field.

    PubMed

    Moise, Eric R D; Henry, Hugh A L

    2014-12-01

    Plant litter decomposition has been studied extensively in the context of both climate warming and increased atmospheric N deposition. However, much of this research is based on microbial responses, despite the potential for detritivores to contribute substantially to litter breakdown. We measured litter mass-loss responses to the combined effects of warming, N addition and detritivore access in a grass-dominated old field. We concurrently assessed the roles of litter treatment origin vs. microenvironment (direct warming and N-addition effects) to elucidate the mechanisms through which these factors affect decomposition. After 6 weeks, mass loss increased in N-addition plots, and it increased with detritivore access in the absence of warming. After 1 year, warming, N addition, and detritivore access all increased litter mass loss, although the effects of N addition and warming were non-additive in the detritivore-access plots. For the litter-origin experiment, mass loss after 6 weeks increased in litter from N-addition plots and warmed plots, but unlike the overall decomposition response, the N-addition effect was enhanced by detritivore access. Conversely, for the microenvironment experiment, detritivore access only increased mass loss in unfertilized plots. After 1 year, detritivore access increased mass loss in the litter-origin and microenvironment experiments, but there were no warming or N-addition effects. Overall, our results provide support for a substantial role of detritivores in promoting litter mass loss in our system. Moreover, they reveal important interactions between litter origin, microclimate and detritivores in determining decomposition responses to global change.

  17. Advanced biostack experiment

    NASA Technical Reports Server (NTRS)

    Buecker, H.

    1981-01-01

    The Advanced Biostack Experiment is described. The objectives are: (1) to confirm, complement, and enlarge the information obtained from the previous experiments by applying improved and advanced methods of localization and physical and biological evaluation, performing advanced experiments based on these data, and including additional biological specimens and additional radiation detectors; (2) to determine the biological importance of nuclear disintegration stars; (3) to determine the interference of HZE particle induced effects with those of other space flight factors (e.g., weightlessness); and (4) to determine the distribution of HZE particles and of disintegration stars at different locations inside the module and on the pallet.

  18. Experience-driven brain plasticity: beyond the synapse

    PubMed Central

    Markham, Julie A.; Greenough, William T.

    2006-01-01

    The brain is remarkably responsive to its interactions with the environment, and its morphology is altered by experience in measurable ways. Histological examination of the brains of animals exposed to either a complex (‘enriched’) environment or learning paradigm, compared with appropriate controls, has illuminated the nature of experience-induced morphological plasticity in the brain. For example, this research reveals that changes in synapse number and morphology are associated with learning and are stable, in that they persist well beyond the period of exposure to the learning experience. In addition, other components of the nervous system also respond to experience: oligodendrocytes and axonal myelination might also be permanently altered, whereas changes in astrocytes and cerebrovasculature are more transient and appear to be activity- rather than learning-driven. Thus, experience induces multiple forms of plasticity in the brain that are apparently regulated, at least in part, by independent mechanisms. PMID:16921405

  19. Additively manufactured porous tantalum implants.

    PubMed

    Wauthle, Ruben; van der Stok, Johan; Amin Yavari, Saber; Van Humbeeck, Jan; Kruth, Jean-Pierre; Zadpoor, Amir Abbas; Weinans, Harrie; Mulier, Michiel; Schrooten, Jan

    2015-03-01

    The medical device industry's interest in open porous, metallic biomaterials has increased in response to additive manufacturing techniques enabling the production of complex shapes that cannot be produced with conventional techniques. Tantalum is an important metal for medical devices because of its good biocompatibility. In this study selective laser melting technology was used for the first time to manufacture highly porous pure tantalum implants with fully interconnected open pores. The architecture of the porous structure in combination with the material properties of tantalum result in mechanical properties close to those of human bone and allow for bone ingrowth. The bone regeneration performance of the porous tantalum was evaluated in vivo using an orthotopic load-bearing bone defect model in the rat femur. After 12 weeks, substantial bone ingrowth, good quality of the regenerated bone and a strong, functional implant-bone interface connection were observed. Compared to identical porous Ti-6Al-4V structures, laser-melted tantalum shows excellent osteoconductive properties, has a higher normalized fatigue strength and allows for more plastic deformation due to its high ductility. It is therefore concluded that this is a first step towards a new generation of open porous tantalum implants manufactured using selective laser melting.

  20. Additive Transforms Paint into Insulation

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Tech Traders Inc. sought assistance developing low-cost, highly effective coatings and paints that created useful thermal reflectance and were safe and non-toxic. In cooperation with a group of engineers at Kennedy Space Center., Tech Traders created Insuladd, a powder additive made up of microscopic, inert gas-filled, ceramic microspheres that can be mixed into ordinary interior or exterior paint, allowing the paint to act like a layer of insulation. When the paint dries, this forms a radiant heat barrier, turning the ordinary house paint into heat-reflecting thermal paint. According to Tech Traders, the product works with all types of paints and coatings and will not change the coverage rate, application, or adhesion of the paint. Other useful applications include feed storage silos to help prevent feed spoilage, poultry hatcheries to reduce the summer heat and winter cold effects, and on military vehicles and ships. Tech Traders has continued its connection to the aerospace community by recently providing Lockheed Martin Corporation with one of its thermal products for use on the F-22 Raptor.

  1. Sustainability Characterization for Additive Manufacturing

    PubMed Central

    Mani, Mahesh; Lyons, Kevin W; Gupta, SK

    2014-01-01

    Additive manufacturing (AM) has the potential to create geometrically complex parts that require a high degree of customization, using less material and producing less waste. Recent studies have shown that AM can be an economically viable option for use by the industry, yet there are some inherent challenges associated with AM for wider acceptance. The lack of standards in AM impedes its use for parts production since industries primarily depend on established standards in processes and material selection to ensure the consistency and quality. Inability to compare AM performance against traditional manufacturing methods can be a barrier for implementing AM processes. AM process sustainability has become a driver due to growing environmental concerns for manufacturing. This has reinforced the importance to understand and characterize AM processes for sustainability. Process characterization for sustainability will help close the gaps for comparing AM performance to traditional manufacturing methods. Based on a literature review, this paper first examines the potential environmental impacts of AM. A methodology for sustainability characterization of AM is then proposed to serve as a resource for the community to benchmark AM processes for sustainability. Next, research perspectives are discussed along with relevant standardization efforts. PMID:26601038

  2. Sustainability Characterization for Additive Manufacturing.

    PubMed

    Mani, Mahesh; Lyons, Kevin W; Gupta, S K

    2014-01-01

    Additive manufacturing (AM) has the potential to create geometrically complex parts that require a high degree of customization, using less material and producing less waste. Recent studies have shown that AM can be an economically viable option for use by the industry, yet there are some inherent challenges associated with AM for wider acceptance. The lack of standards in AM impedes its use for parts production since industries primarily depend on established standards in processes and material selection to ensure the consistency and quality. Inability to compare AM performance against traditional manufacturing methods can be a barrier for implementing AM processes. AM process sustainability has become a driver due to growing environmental concerns for manufacturing. This has reinforced the importance to understand and characterize AM processes for sustainability. Process characterization for sustainability will help close the gaps for comparing AM performance to traditional manufacturing methods. Based on a literature review, this paper first examines the potential environmental impacts of AM. A methodology for sustainability characterization of AM is then proposed to serve as a resource for the community to benchmark AM processes for sustainability. Next, research perspectives are discussed along with relevant standardization efforts.

  3. Dynamics of ultrasonic additive manufacturing.

    PubMed

    Hehr, Adam; Dapino, Marcelo J

    2017-01-01

    Ultrasonic additive manufacturing (UAM) is a solid-state technology for joining similar and dissimilar metal foils near room temperature by scrubbing them together with ultrasonic vibrations under pressure. Structural dynamics of the welding assembly and work piece influence how energy is transferred during the process and ultimately, part quality. To understand the effect of structural dynamics during UAM, a linear time-invariant model is proposed to relate the inputs of shear force and electric current to resultant welder velocity and voltage. Measured frequency response and operating performance of the welder under no load is used to identify model parameters. Using this model and in-situ measurements, shear force and welder efficiency are estimated to be near 2000N and 80% when welding Al 6061-H18 weld foil, respectively. Shear force and welder efficiency have never been estimated before in UAM. The influence of processing conditions, i.e., welder amplitude, normal force, and weld speed, on shear force and welder efficiency are investigated. Welder velocity was found to strongly influence the shear force magnitude and efficiency while normal force and weld speed showed little to no influence. The proposed model is used to describe high frequency harmonic content in the velocity response of the welder during welding operations and coupling of the UAM build with the welder.

  4. Dimensionless numbers in additive manufacturing

    NASA Astrophysics Data System (ADS)

    Mukherjee, T.; Manvatkar, V.; De, A.; DebRoy, T.

    2017-02-01

    The effects of many process variables and alloy properties on the structure and properties of additively manufactured parts are examined using four dimensionless numbers. The structure and properties of components made from 316 Stainless steel, Ti-6Al-4V, and Inconel 718 powders for various dimensionless heat inputs, Peclet numbers, Marangoni numbers, and Fourier numbers are studied. Temperature fields, cooling rates, solidification parameters, lack of fusion defects, and thermal strains are examined using a well-tested three-dimensional transient heat transfer and fluid flow model. The results show that lack of fusion defects in the fabricated parts can be minimized by strengthening interlayer bonding using high values of dimensionless heat input. The formation of harmful intermetallics such as laves phases in Inconel 718 can be suppressed using low heat input that results in a small molten pool, a steep temperature gradient, and a fast cooling rate. Improved interlayer bonding can be achieved at high Marangoni numbers, which results in vigorous circulation of liquid metal, larger pool dimensions, and greater depth of penetration. A high Fourier number ensures rapid cooling, low thermal distortion, and a high ratio of temperature gradient to the solidification growth rate with a greater tendency of plane front solidification.

  5. Children's understanding of additive concepts.

    PubMed

    Robinson, Katherine M; Dubé, Adam K; Beatch, Jacqueline-Ann

    2017-04-01

    Most research on children's arithmetic concepts is based on one concept at a time, limiting the conclusions that can be made about how children's conceptual knowledge of arithmetic develops. This study examined six arithmetic concepts (identity, negation, commutativity, equivalence, inversion, and addition and subtraction associativity) in Grades 3, 4, and 5. Identity (a-0=a) and negation (a-a=0) were well understood, followed by moderate understanding of commutativity (a+b=b+a) and inversion (a+b-b=a), with weak understanding of equivalence (a+b+c=a+[b+c]) and associativity (a+b-c=[b-c]+a). Understanding increased across grade only for commutativity and equivalence. Four clusters were found: The Weak Concept cluster understood only identity and negation; the Two-Term Concept cluster also understood commutativity; the Inversion Concept cluster understood identity, negation, and inversion; and the Strong Concept cluster had the strongest understanding of all of the concepts. Grade 3 students tended to be in the Weak and Inversion Concept clusters, Grade 4 students were equally likely to be in any of the clusters, and Grade 5 students were most likely to be in the Two-Term and Strong Concept clusters. The findings of this study highlight that conclusions about the development of arithmetic concepts are highly dependent on which concepts are being assessed and underscore the need for multiple concepts to be investigated at the same time.

  6. Additional Crime Scenes for Projectile Motion Unit

    NASA Astrophysics Data System (ADS)

    Fullerton, Dan; Bonner, David

    2011-12-01

    Building students' ability to transfer physics fundamentals to real-world applications establishes a deeper understanding of underlying concepts while enhancing student interest. Forensic science offers a great opportunity for students to apply physics to highly engaging, real-world contexts. Integrating these opportunities into inquiry-based problem solving in a team environment provides a terrific backdrop for fostering communication, analysis, and critical thinking skills. One such activity, inspired jointly by the museum exhibit "CSI: The Experience"2 and David Bonner's TPT article "Increasing Student Engagement and Enthusiasm: A Projectile Motion Crime Scene,"3 provides students with three different crime scenes, each requiring an analysis of projectile motion. In this lesson students socially engage in higher-order analysis of two-dimensional projectile motion problems by collecting information from 3-D scale models and collaborating with one another on its interpretation, in addition to diagramming and mathematical analysis typical to problem solving in physics.

  7. Students' Perspectives on University Experiences; The Role of Protective Factors in Students' Lives

    ERIC Educational Resources Information Center

    Jdaitawi, Malek; Maya-Panorama; Nawafleh, Ahmad; Nabrawi, Ismaeel; Talafha, Feras; Mohd, Amani

    2013-01-01

    This study examined the relationship between protective factors and students' university experiences among 289 first year university students. The study made use of exploratory and confirmatory factor analyses to reveal initial support for the research variables. In addition, path analysis was utilized to investigate the relationship among the…

  8. Electric utility use of fireside additives. Final report

    SciTech Connect

    Locklin, D.W.; Krause, H.H.; Anson, D.; Reid, W.

    1980-01-01

    Fireside additives have been used or proposed for use in fossil-fired utility boilers to combat a number of problems related to boiler performance and reliability. These problems include corrosion, fouling, superheat control, and acidic emissions. Fuel additives and other fireside additives have been used mainly with oil firing; however, there is growing experience with additives in coal-firing, especially for flyash conditioning to improve the performance of electrostatic precipitators. In decisions regarding the selection and use of additives, utilities have had to rely extensively on empiricism, due partly to an incomplete understanding of processes involved and partly to the limited amount of quantitative data. The study reported here was sponsored by the Electric Power Research Institute to assemble and analyze pertinent operating experience and to recommend guidelines for utility decisions on the use of additives. The combined results of the state-of-the-art review of technical literature and a special survey of utility experience are reported. A total of 38 utilities participated in the survey, providing information on trials conducted on 104 units in 93 different plants. Altogether, 445 separate trials were reported, each representing a unit/additive/fuel combination. Additives used in these trials included 90 different additive formulations, both pure compounds and proprietary products. These formulations were categorized into 37 generic classes according to their chemical constituents, and the results of the survey are presented by these generic classes. The findings are organized according to the operating problems for which fireside additives are used. Guidelines are presented for utility use in additive selection and in planning additive trials.

  9. Enhancement of Corrosion Resistance of Zinc Coatings Using Green Additives

    NASA Astrophysics Data System (ADS)

    Punith Kumar, M. K.; Srivastava, Chandan

    2014-10-01

    In the present work, morphology, microstructure, and electrochemical behavior of Zn coatings containing non-toxic additives have been investigated. Zn coatings were electrodeposited over mild steel substrates using Zn sulphate baths containing four different organic additives: sodium gluconate, dextrose, dextrin, and saccharin. All these additives are "green" and can be derived from food contents. Morphological and structural characterization using electron microscopy, x-ray diffraction, and texture co-efficient analysis revealed an appreciable alteration in the morphology and texture of the deposit depending on the type of additive used in the Zn plating bath. All the Zn coatings, however, were nano-crystalline irrespective of the type of additive used. Polarization and electrochemical impedance spectroscopic analysis, used to investigate the effect of the change in microstructure and morphology on corrosion resistance behavior, illustrated an improved corrosion resistance for Zn deposits obtained from plating bath containing additives as compared to the pure Zn coatings.

  10. Efficient Improvement of Silage Additives by Using Genetic Algorithms

    PubMed Central

    Davies, Zoe S.; Gilbert, Richard J.; Merry, Roger J.; Kell, Douglas B.; Theodorou, Michael K.; Griffith, Gareth W.

    2000-01-01

    The enormous variety of substances which may be added to forage in order to manipulate and improve the ensilage process presents an empirical, combinatorial optimization problem of great complexity. To investigate the utility of genetic algorithms for designing effective silage additive combinations, a series of small-scale proof of principle silage experiments were performed with fresh ryegrass. Having established that significant biochemical changes occur over an ensilage period as short as 2 days, we performed a series of experiments in which we used 50 silage additive combinations (prepared by using eight bacterial and other additives, each of which was added at six different levels, including zero [i.e., no additive]). The decrease in pH, the increase in lactate concentration, and the free amino acid concentration were measured after 2 days and used to calculate a “fitness” value that indicated the quality of the silage (compared to a control silage made without additives). This analysis also included a “cost” element to account for different total additive levels. In the initial experiment additive levels were selected randomly, but subsequently a genetic algorithm program was used to suggest new additive combinations based on the fitness values determined in the preceding experiments. The result was very efficient selection for silages in which large decreases in pH and high levels of lactate occurred along with low levels of free amino acids. During the series of five experiments, each of which comprised 50 treatments, there was a steady increase in the amount of lactate that accumulated; the best treatment combination was that used in the last experiment, which produced 4.6 times more lactate than the untreated silage. The additive combinations that were found to yield the highest fitness values in the final (fifth) experiment were assessed to determine a range of biochemical and microbiological quality parameters during full-term silage

  11. Efficient improvement of silage additives by using genetic algorithms.

    PubMed

    Davies, Z S; Gilbert, R J; Merry, R J; Kell, D B; Theodorou, M K; Griffith, G W

    2000-04-01

    The enormous variety of substances which may be added to forage in order to manipulate and improve the ensilage process presents an empirical, combinatorial optimization problem of great complexity. To investigate the utility of genetic algorithms for designing effective silage additive combinations, a series of small-scale proof of principle silage experiments were performed with fresh ryegrass. Having established that significant biochemical changes occur over an ensilage period as short as 2 days, we performed a series of experiments in which we used 50 silage additive combinations (prepared by using eight bacterial and other additives, each of which was added at six different levels, including zero [i.e. , no additive]). The decrease in pH, the increase in lactate concentration, and the free amino acid concentration were measured after 2 days and used to calculate a "fitness" value that indicated the quality of the silage (compared to a control silage made without additives). This analysis also included a "cost" element to account for different total additive levels. In the initial experiment additive levels were selected randomly, but subsequently a genetic algorithm program was used to suggest new additive combinations based on the fitness values determined in the preceding experiments. The result was very efficient selection for silages in which large decreases in pH and high levels of lactate occurred along with low levels of free amino acids. During the series of five experiments, each of which comprised 50 treatments, there was a steady increase in the amount of lactate that accumulated; the best treatment combination was that used in the last experiment, which produced 4.6 times more lactate than the untreated silage. The additive combinations that were found to yield the highest fitness values in the final (fifth) experiment were assessed to determine a range of biochemical and microbiological quality parameters during full-term silage fermentation. We

  12. Additives In Meat and Poultry Products

    MedlinePlus

    ... What is a food additive? What is a "direct" food additive? What is an 'indirect" food additive? ... convenience foods. [ Top of Page ] What is a “direct” food additive? According to the FDA, “Direct food ...

  13. Replication Study: Melanoma genome sequencing reveals frequent PREX2 mutations

    PubMed Central

    Horrigan, Stephen K; Courville, Pascal; Sampey, Darryl; Zhou, Faren; Cai, Steve

    2017-01-01

    In 2015, as part of the Reproducibility Project: Cancer Biology, we published a Registered Report (Chroscinski et al., 2014) that described how we intended to replicate selected experiments from the paper "Melanoma genome sequencing reveals frequent PREX2 mutations" (Berger et al., 2012). Here we report the results of those experiments. We regenerated cells stably expressing ectopic wild-type and mutant phosphatidylinositol-3,4,5-trisphosphate-dependent Rac exchange factor 2 (PREX2) using the same immortalized human NRASG12D melanocytes as the original study. Evaluation of PREX2 expression in these newly generated stable cells revealed varying levels of expression among the PREX2 isoforms, which was also observed in the stable cells made in the original study (Figure S6A; Berger et al., 2012). Additionally, ectopically expressed PREX2 was found to be at least 5 times above endogenous PREX2 expression. The monitoring of tumor formation of these stable cells in vivo resulted in no statistically significant difference in tumor-free survival driven by PREX2 variants, whereas the original study reported that these PREX2 mutations increased the rate of tumor incidence compared to controls (Figure 3B and S6B; Berger et al., 2012). Surprisingly, the median tumor-free survival was 1 week in this replication attempt, while 70% of the control mice were reported to be tumor-free after 9 weeks in the original study. The rapid tumor onset observed in this replication attempt, compared to the original study, makes the detection of accelerated tumor growth in PREX2 expressing NRASG12D melanocytes extremely difficult. Finally, we report meta-analyses for each result. DOI: http://dx.doi.org/10.7554/eLife.21634.001 PMID:28100394

  14. Psychology Experiments.

    ERIC Educational Resources Information Center

    McGraw, Ken; Tew, Mark D.; Williams, John E.

    2001-01-01

    A goal of the PsychExperiments project was to reduce the financial burden on psychology departments for hardware/software used in their laboratories. In its third year, the PsychExperiments site now hosts 39 experiments. Over 200 classrooms worldwide have signed up as official site users and there have been nearly 10,000 data sessions conducted.…

  15. Layered gadolinium hydroxides for low-temperature magnetic cooling† †Electronic supplementary information (ESI) available: Experimental details, PXRD analysis, SEM experiments, and isothermal magnetization curves. See DOI: 10.1039/c5cc05150a Click here for additional data file.

    PubMed Central

    Abellán, Gonzalo; Espallargas, Guillermo Mínguez; Lorusso, Giulia

    2015-01-01

    Layered gadolinium hydroxides have revealed to be excellent candidates for cryogenic magnetic refrigeration. These materials behave as pure 2D magnetic systems with a Heisenberg–Ising critical crossover, induced by dipolar interactions. This 2D character and the possibility offered by these materials to be delaminated open the possibility of rapid heat dissipation upon substrate deposition. PMID:26256944

  16. Electric utility use of fireside additives. Final report

    SciTech Connect

    Locklin, D.W.; Krause, H.H.; Anson, D.; Reid, W.

    1980-01-01

    Fireside additives have been used or proposed for use in fossil-fired utility boilers to combat a number of problems related to boiler performance and reliability. These problems include corrosion, fouling, superheat control, and acidic emissions. Fuel additivies and other fireside additives have been used mainly with oil firing; however, there is growing experience with additives in coal-firing, especially for flyash conditioning to improve the performance of electrostatic precipitators. In decisions regarding the selection and use of additives, utilities have had to rely extensively on empiricism, due partly to our incomplete understanding of processes involved and partly to the limited amount of quantitative data. The study reported here was sponsored by the Electric Power Research Institute to assemble and analyze pertinent operating experience and to recommend guidelines for utility decisions on the use of additives. This report describes the combined results of the state-of-the-art review of technical literature and a special survey of utility experience. A total of 38 utilities participated in the survey, providing information on trials conducted on 104 units in 93 different plants. Altogether, 445 separate trials were reported, each representing a unit/additive/fuel combination. 90 different additive formulations, both pure compounds and proprietary products, were categorized into 37 generic classes according to their chemical constituents, and the results of the survey are presented by these generic classes. This report is organized according to the operating problems for which fireside additives are used. Guidelines are presented for utility use in additive selection and in planning additive trials.

  17. Effects of some polymeric additives on the cocrystallization of caffeine

    NASA Astrophysics Data System (ADS)

    Chung, Jihae; Kim, Il Won

    2011-11-01

    Effects of polymeric additives on the model cocrystallization were examined. The model cocrystal was made from caffeine and oxalic acid, and poly(ethylene glycol) (PEG), poly( L-lactide) (PLLA), poly(ɛ-caprolactone) (PCL), and poly(acrylic acid) (PAA) were the additives. The cocrystals were formed as millimeter-sized crystals without additives, and they became microcrystals with PLLA and PCL, and nanocrystals with PAA. XRD and IR revealed that the cocrystal structure was unchanged despite the strong effects of the additives on the crystal morphology, although some decrease in crystallinity was observed with PAA as confirmed by DSC. The DSC study also showed that the cocrystal melted and recrystallized to form α-caffeine upon heating. The present study verified that the polymeric additives can be utilized to modulate the size and morphology of the cocrystals without interfering the intermolecular interactions essential to the integrity of the cocrystal structures.

  18. 21 CFR 170.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES Food Additive... proposed experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a food additive whether he believes the experiments planned will yield data adequate...

  19. 21 CFR 170.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES Food Additive... proposed experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a food additive whether he believes the experiments planned will yield data adequate...

  20. 21 CFR 170.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES Food Additive... proposed experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a food additive whether he believes the experiments planned will yield data adequate...

  1. 21 CFR 570.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES Food Additive... and the proposed experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a food additive whether he believes the experiments planned will...

  2. 21 CFR 570.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES Food Additive... and the proposed experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a food additive whether he believes the experiments planned will...

  3. 21 CFR 570.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES Food Additive... and the proposed experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a food additive whether he believes the experiments planned will...

  4. 21 CFR 570.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES Food Additive... and the proposed experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a food additive whether he believes the experiments planned will...

  5. 21 CFR 570.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES Food Additive... and the proposed experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a food additive whether he believes the experiments planned will...

  6. 21 CFR 170.20 - General principles for evaluating the safety of food additives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES Food Additive... proposed experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a food additive whether he believes the experiments planned will yield data adequate...

  7. [Nephrocutaneous fistula revealing xanthogranulomatous pyelonephritis].

    PubMed

    Scotté, M; Sibert, L; Soury, P; Lebret, T; Gobet, F; Grise, P; Tenière, P

    1993-01-01

    A patient presented with a reno-cutaneous fistula revealing a xanthogranulomatous pyelonephritis secondary to staghorn calculus. Total nephrectomy was necessary because of renal destruction. This treatment allowed closure of the fistula and a good clinical result.

  8. Stacking sequence and interlayer coupling in few-layer graphene revealed by in situ imaging

    SciTech Connect

    Wang, Zhu-Jun; Dong, Jichen; Cui, Yi; Eres, Gyula; Timpe, Olaf; Fu, Qiang; Ding, Feng; Willinger, Marc-Georg; Schloegl, R.

    2016-10-19

    In the transition from graphene to graphite, the addition of each individual graphene layer modifies the electronic structure and produces a different material with unique properties. Controlled growth of few-layer graphene is therefore of fundamental interest and will provide access to materials with engineered electronic structure. Here we combine isothermal growth and etching experiments with in situ scanning electron microscopy to reveal the stacking sequence and interlayer coupling strength in few-layer graphene. The observed layer-dependent etching rates reveal the relative strength of the graphene graphene and graphene substrate interaction and the resulting mode of adlayer growth. Scanning tunnelling microscopy and density functional theory calculations confirm a strong coupling between graphene edge atoms and platinum. Simulated etching confirms that etching can be viewed as reversed growth. This work demonstrates that real-time imaging under controlled atmosphere is a powerful method for designing synthesis protocols for sp2 carbon nanostructures in between graphene and graphite.

  9. Stacking sequence and interlayer coupling in few-layer graphene revealed by in situ imaging

    NASA Astrophysics Data System (ADS)

    Wang, Zhu-Jun; Dong, Jichen; Cui, Yi; Eres, Gyula; Timpe, Olaf; Fu, Qiang; Ding, Feng; Schloegl, R.; Willinger, Marc-Georg

    2016-10-01

    In the transition from graphene to graphite, the addition of each individual graphene layer modifies the electronic structure and produces a different material with unique properties. Controlled growth of few-layer graphene is therefore of fundamental interest and will provide access to materials with engineered electronic structure. Here we combine isothermal growth and etching experiments with in situ scanning electron microscopy to reveal the stacking sequence and interlayer coupling strength in few-layer graphene. The observed layer-dependent etching rates reveal the relative strength of the graphene-graphene and graphene-substrate interaction and the resulting mode of adlayer growth. Scanning tunnelling microscopy and density functional theory calculations confirm a strong coupling between graphene edge atoms and platinum. Simulated etching confirms that etching can be viewed as reversed growth. This work demonstrates that real-time imaging under controlled atmosphere is a powerful method for designing synthesis protocols for sp2 carbon nanostructures in between graphene and graphite.

  10. Overview of Food Ingredients, Additives and Colors

    MedlinePlus

    ... pesticides where other legal premarket approval requirements apply. Direct food additives are those that are added to ... and other foods to add texture -- is a direct additive. Most direct additives are identified on the ...

  11. Prevenar experience.

    PubMed

    Arguedas, Adriano; Soley, Carolina; Abdelnour, Arturo

    2011-09-14

    Streptococcus pneumoniae is one of the leading bacterial pathogens causing invasive disease and non-invasive infections at both extremes of life: in children younger than 5 years and in elderly persons of 65 years or more. Pneumococcal infections result in substantial morbidity and mortality among children under 5 years of age; it is estimated that 1,600,000 deaths occur per year in that age range alone, mostly in developing countries, thus representing a serious public health problem around the globe. Infections caused by S. pneumoniae are considered by the World Health Organization (WHO) as the number one vaccine-preventable cause of death in children younger than 5 years of age. In 2000, the first heptavalent conjugated pneumococcal vaccine (PCV7) was licensed in the United States, differing from the already available non-conjugated polysaccharide pneumococcal vaccine in its ability to induce a protective immune response in children under 2 years of age. Initial efficacy studies in the United States with PCV7 revealed a 97.4% efficacy against invasive pneumococcal disease (IPD) caused by vaccine serotypes (4, 9V, 14, 19F, 23F, 18C and 6B). PCV7 was introduced into the National Immunization Program (NIP) of various countries starting in year 2000 and, after 11 years of use, the data confirm that PCV7 introduction resulted in a major reduction of S. pneumoniae IPD, non-bacteremic pneumonia, otitis media medical visits, the need for tympanic tubes, the number of cases of otorrhea and of various antimicrobial resistant strains in children <5 years of age. Additionally, reductions in S. pneumoniae infections have been observed in unvaccinated children above 5 years of age and adults including individuals older than 65 years of age (herd effect). Effectiveness has been observed in countries using a 4-dose regimen (3 infant doses followed by a booster during the second year of life) but also in countries with modified reduced doses (2 infant doses and a booster during

  12. Uniform Additivity in Classical and Quantum Information

    NASA Astrophysics Data System (ADS)

    Cross, Andrew; Li, Ke; Smith, Graeme

    2017-01-01

    Information theory quantifies the optimal rates of resource interconversions, usually in terms of entropies. However, nonadditivity often makes evaluating entropic formulas intractable. In a few auspicious cases, additivity allows a full characterization of optimal rates. We study uniform additivity of formulas, which is easily evaluated and captures all known additive quantum formulas. Our complete characterization of uniform additivity exposes an intriguing new additive quantity and identifies a remarkable coincidence—the classical and quantum uniformly additive functions with one auxiliary variable are identical.

  13. Children's patterns of reasoning about reading and addition concepts.

    PubMed

    Farrington-Flint, Lee; Canobi, Katherine H; Wood, Clare; Faulkner, Dorothy

    2010-06-01

    Children's reasoning was examined within two educational contexts (word reading and addition) so as to understand the factors that contribute to relational reasoning in the two domains. Sixty-seven 5- to 7-year-olds were given a series of related words to read or single-digit addition items to solve (interspersed with unrelated items). The frequency, accuracy, and response times of children's self-reports on the conceptually related items provided a measure of relational reasoning, while performance on the unrelated addition and reading items provided a measure of procedural skill. The results indicated that the children's ability to use conceptual relations to solve both reading and addition problems enhanced speed and accuracy levels, increased with age, and was related to procedural skill. However, regression analyses revealed that domain-specific competencies can best explain the use of conceptual relations in both reading and addition. Moreover, a cluster analysis revealed that children differ according to the academic domain in which they first apply conceptual relations and these differences are related to individual variation in their procedural skills within these particular domains. These results highlight the developmental significance of relational reasoning in the context of reading and addition and underscore the importance of concept-procedure links in explaining children's literacy and arithmetical development.

  14. Symbiotic conversations are revealed under genetic interrogation

    PubMed Central

    Ruby, Edward G.

    2013-01-01

    The recent development and application of molecular genetics to the symbionts of invertebrate animal species have advanced our knowledge of the biochemical communication that occurs between the host and its bacterial symbionts. In particular, the ability to manipulate these associations experimentally by introducing genetic variants of the symbionts into naive hosts has allowed the discovery of novel colonization mechanisms and factors. In addition, the role of the symbionts in inducing normal host development has been revealed, and its molecular basis described. In this Review, I discuss many of these developments, focusing on what has been discovered in five well-understood model systems. PMID:18794913

  15. 16 CFR 1102.16 - Additional information.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... PUBLICLY AVAILABLE CONSUMER PRODUCT SAFETY INFORMATION DATABASE Content Requirements § 1102.16 Additional... in the Database any additional information it determines to be in the public interest,...

  16. 16 CFR 1102.16 - Additional information.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... PUBLICLY AVAILABLE CONSUMER PRODUCT SAFETY INFORMATION DATABASE Content Requirements § 1102.16 Additional... in the Database any additional information it determines to be in the public interest,...

  17. 16 CFR 1102.16 - Additional information.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... PUBLICLY AVAILABLE CONSUMER PRODUCT SAFETY INFORMATION DATABASE Content Requirements § 1102.16 Additional... in the Database any additional information it determines to be in the public interest,...

  18. 40 CFR 262.43 - Additional reporting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) STANDARDS APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Recordkeeping and Reporting § 262.43 Additional... require generators to furnish additional reports concerning the quantities and disposition of...

  19. 40 CFR 262.43 - Additional reporting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) STANDARDS APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Recordkeeping and Reporting § 262.43 Additional... require generators to furnish additional reports concerning the quantities and disposition of...

  20. 40 CFR 262.43 - Additional reporting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) STANDARDS APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Recordkeeping and Reporting § 262.43 Additional... require generators to furnish additional reports concerning the quantities and disposition of...

  1. 40 CFR 262.43 - Additional reporting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) STANDARDS APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Recordkeeping and Reporting § 262.43 Additional... require generators to furnish additional reports concerning the quantities and disposition of...

  2. 40 CFR 262.43 - Additional reporting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) STANDARDS APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Recordkeeping and Reporting § 262.43 Additional... require generators to furnish additional reports concerning the quantities and disposition of...

  3. THERMAL DISTRIBUTION SYSTEM EXPERIMENT

    SciTech Connect

    KRAJEWSKI,R.F.; ANDREWS,J.W.; WEI,G.

    1999-09-01

    A laboratory experiment has been conducted which tests for the effects of distribution system purging on system Delivery Effectiveness (DE) as defined in ASHRAE 152P. The experiment is described in its configuration, instrumentation, and data acquisition system. Data gathered in the experiment is given and discussed. The results show that purging of the distribution system alone does not offer any improvement of the system DE. Additional supporting tests were conducted regarding experimental simulations of buffer zones and bare pipe and are also discussed.

  4. Benefits of additives application during combustion of phytomass

    NASA Astrophysics Data System (ADS)

    Palacka, Matej; Vician, Peter; Holubčík, Michal; Jandačka, Jozef

    2016-06-01

    Phytomass, particularly wheat straw as a source of energy has countless benefits, but it has many problems in its direct burn too. The worst problem is the ash flow temperature. The aim of study was to analyze and reduce the problems of the wheat straw combustion. The experiment was conducted under realistic conditions. In this paper was implemented analysis of ash features with and without adding additives into the wheat straw. Selected samples were laboratory processed and examined. The result of the work was the impact of additional additives for ash features.

  5. IN718 Additive Manufacturing Properties and Influences

    NASA Technical Reports Server (NTRS)

    Lambert, Dennis M.

    2015-01-01

    The results of tensile, fracture, and fatigue testing of IN718 coupons produced using the selective laser melting (SLM) additive manufacturing technique are presented. The data have been "sanitized" to remove the numerical values, although certain references to material standards are provided. This document provides some knowledge of the effect of variation of controlled build parameters used in the SLM process, a snapshot of the capabilities of SLM in industry at present, and shares some of the lessons learned along the way. For the build parameter characterization, the parameters were varied over a range that was centered about the machine manufacturer's recommended value, and in each case they were varied individually, although some co-variance of those parameters would be expected. Tensile, fracture, and high-cycle fatigue properties equivalent to wrought IN718 are achievable with SLM-produced IN718. Build and post-build processes need to be determined and then controlled to established limits to accomplish this. It is recommended that a multi-variable evaluation, e.g., design-of experiment (DOE), of the build parameters be performed to better evaluate the co-variance of the parameters.

  6. Computational Process Modeling for Additive Manufacturing (OSU)

    NASA Technical Reports Server (NTRS)

    Bagg, Stacey; Zhang, Wei

    2015-01-01

    Powder-Bed Additive Manufacturing (AM) through Direct Metal Laser Sintering (DMLS) or Selective Laser Melting (SLM) is being used by NASA and the Aerospace industry to "print" parts that traditionally are very complex, high cost, or long schedule lead items. The process spreads a thin layer of metal powder over a build platform, then melts the powder in a series of welds in a desired shape. The next layer of powder is applied, and the process is repeated until layer-by-layer, a very complex part can be built. This reduces cost and schedule by eliminating very complex tooling and processes traditionally used in aerospace component manufacturing. To use the process to print end-use items, NASA seeks to understand SLM material well enough to develop a method of qualifying parts for space flight operation. Traditionally, a new material process takes many years and high investment to generate statistical databases and experiential knowledge, but computational modeling can truncate the schedule and cost -many experiments can be run quickly in a model, which would take years and a high material cost to run empirically. This project seeks to optimize material build parameters with reduced time and cost through modeling.

  7. IN718 Additive Manufacturing Properties and Influences

    NASA Technical Reports Server (NTRS)

    Lambert, Dennis M.

    2015-01-01

    The results of tensile, fracture, and fatigue testing of IN718 coupons produced using the selective laser melting (SLM) additive manufacturing technique are presented. The data has been "generalized" to remove the numerical values, although certain references to material standards are provided. This document provides some knowledge of the effect of variation of controlled build parameters used in the SLM process, a snapshot of the capabilities of SLM in industry at present, and shares some of the lessons learned along the way. For the build parameter characterization, the parameters were varied over a range about the machine manufacturer's recommended value, and in each case they were varied individually, although some co-variance of those parameters would be expected. SLM-produced IN718, tensile, fracture, and high-cycle fatigue properties equivalent to wrought IN718 are achievable. Build and post-build processes need to be determined and then controlled to established limits to accomplish this. It is recommended that a multi-variable evaluation, e.g., design-of-experiment (DOE), of the build parameters be performed to better evaluate the co-variance of the parameters.

  8. Improved surface property of PVDF membrane with amphiphilic zwitterionic copolymer as membrane additive

    NASA Astrophysics Data System (ADS)

    Li, Jian-Hua; Li, Mi-Zi; Miao, Jing; Wang, Jia-Bin; Shao, Xi-Sheng; Zhang, Qi-Qing

    2012-06-01

    An attempt to improve hydrophilicity and anti-fouling properties of PVDF membranes, a novel amphiphilic zwitterionic copolymer poly(vinylidene fluoride)-graft-poly(sulfobetaine methacrylate) (PVDF-g-PSBMA) was firstly synthesized by atom transfer radical polymerization (ATRP) and used as amphiphilic copolymer additive in the preparation of PVDF membranes. The PVDF-g-PSBMA/PVDF blend membranes were prepared by immersion precipitation process. Fourier transform infrared attenuated reflection spectroscopy (FTIR-ATR) and X-ray photoelectronic spectroscopy (XPS) measurements confirmed that PSBMA brushes from amphiphilic additives were preferentially segregated to membrane-coagulant interface during membrane formation. The morphology of membranes was characterized by scanning electron microscopy (SEM). Water contact angle measurements showed that the surface hydrophilicity of PVDF membranes was improved significantly with the increasing of amphiphilic copolymer PVDF-g-PSBMA in cast solution. Protein static adsorption experiment and dynamic fouling resistance experiment revealed that the surface enrichment of PSBMA brush endowed PVDF blend membrane great improvement of surface anti-fouling ability.

  9. Co-occurring nonnative woody shrubs have additive and non-additive soil legacies.

    PubMed

    Kuebbing, Sara E; Patterson, Courtney M; Classen, Aimée T; Simberloff, Daniel

    2016-09-01

    To maximize limited conservation funds and prioritize management projects that are likely to succeed, accurate assessment of invasive nonnative species impacts is essential. A common challenge to prioritization is a limited knowledge of the difference between the impacts of a single nonnative species compared to the impacts of nonnative species when they co-occur, and in particular predicting when impacts of co-occurring nonnative species will be non-additive. Understanding non-additivity is important for management decisions because the management of only one co-occurring invader will not necessarily lead to a predictable reduction in the impact or growth of the other nonnative plant. Nonnative plants are frequently associated with changes in soil biotic and abiotic characteristics, which lead to plant-soil interactions that influence the performance of other species grown in those soils. Whether co-occurring nonnative plants alter soil properties additively or non-additively relative to their effects on soils when they grow in monoculture is rarely addressed. We use a greenhouse plant-soil feedback experiment to test for non-additive soil impacts of two common invasive nonnative woody shrubs, Lonicera maackii and Ligustrum sinense, in deciduous forests of the southeastern United States. We measured the performance of each nonnative shrub, a native herbaceous community, and a nonnative woody vine in soils conditioned by each shrub singly or together in polyculture. Soils conditioned by both nonnative shrubs had non-additive impacts on native and nonnative performance. Root mass of the native herbaceous community was 1.5 times lower and the root mass of the nonnative L. sinense was 1.8 times higher in soils conditioned by both L. maackii and L. sinense than expected based upon growth in soils conditioned by either shrub singly. This result indicates that when these two nonnative shrubs co-occur, their influence on soils disproportionally favors persistence

  10. Relativistic Velocity Addition Law from Machine Gun Analogy

    ERIC Educational Resources Information Center

    Rothenstein, Bernhard; Popescu, Stefan

    2009-01-01

    Many derivations of the relativistic addition law of parallel velocities without use of the Lorentz transformations (LT) are known. Some of them are based on thought experiments that require knowledge of the time dilation and the length contraction effects. Other derivations involve the Doppler effect in the optic domain considered from three…

  11. Optimal Multicomponent Analysis Using the Generalized Standard Addition Method.

    ERIC Educational Resources Information Center

    Raymond, Margaret; And Others

    1983-01-01

    Describes an experiment on the simultaneous determination of chromium and magnesium by spectophotometry modified to include the Generalized Standard Addition Method computer program, a multivariate calibration method that provides optimal multicomponent analysis in the presence of interference and matrix effects. Provides instructions for…

  12. Modulation of additive and interactive effects by trial history revisited.

    PubMed

    Masson, Michael E J; Rabe, Maximilian M; Kliegl, Reinhold

    2017-04-01

    Masson and Kliegl (Journal of Experimental Psychology: Learning, Memory, and Cognition, 39, 898-914, 2013) reported evidence that the nature of the target stimulus on the previous trial of a lexical decision task modulates the effects of independent variables on the current trial, including additive versus interactive effects of word frequency and stimulus quality. In contrast, recent reanalyses of previously published data from experiments that, unlike the Masson and Kliegl experiments, did not include semantic priming as a factor, found no evidence for modulation of additive effects of frequency and stimulus quality by trial history (Balota, Aschenbrenner, & Yap, Journal of Experimental Psychology: Learning, Memory, and Cognition, 39, 1563-1571, 2013; O'Malley & Besner, Journal of Experimental Psychology: Learning, Memory, and Cognition, 34, 1400-1411, 2013). We report two experiments that included semantic priming as a factor and that attempted to replicate the modulatory effects found by Masson and Kliegl. In neither experiment was additivity of frequency and stimulus quality modulated by trial history, converging with the findings reported by Balota et al. and O'Malley and Besner. Other modulatory influences of trial history, however, were replicated in the new experiments and reflect potential trial-by-trial alterations in decision processes.

  13. Polyfibroblast: A Self-Healing and Galvanic Protection Additive

    DTIC Science & Technology

    2011-04-25

    of premature microcapsule rupture, and have shown that the microcapsules are resilient to solvent soaking. 2 Project Goals and Objectives This month...capability of Polyfibroblast microcapsules , we designed the following test. We short-circuited a A1008 steel specimen to a strip of polyurethane...pH New experiments have revealed that alkaline plating baths etch the polymer skin layer. Fresh microcapsules placed in plating baths with a pH of

  14. 14 CFR 1274.917 - Additional funds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Additional funds. 1274.917 Section 1274.917... FIRMS Other Provisions and Special Conditions § 1274.917 Additional funds. Additional Funds July 2002... under the terms of this cooperative agreement. NASA is under no obligation to provide additional...

  15. The role of conceptual understanding in children's addition problem solving.

    PubMed

    Canobi, K H; Reeve, R A; Pattison, P E

    1998-09-01

    The study examined the relationship between children's conceptual understanding and addition problem-solving procedures. Forty-eight 6- to 8-year-olds solved addition problems and, in a 2nd task, were prompted to judge whether a puppet could use the arithmetic properties of one problem to solve the next problem. Relational properties between consecutive problems were manipulated to reflect aspects of additive composition, commutativity, and associativity principles. Conceptual understanding was assessed by the ability to spontaneously use such relational properties in problem solving (Task 1) and to recognize and explain them when prompted (Task 2). Results revealed that conceptual understanding was related to using order-indifferent, decomposition, and retrieval strategies and speed and accuracy in solving unrelated problems. The importance of conceptual understanding for addition development is discussed.

  16. Simulated Experiments

    ERIC Educational Resources Information Center

    Snadden, R. B.; Runquist, O.

    1975-01-01

    Presents an experiment in which a programmable calculator is employed as a data generating system for simulated laboratory experiments. The example used as an illustration is a simulated conductimetric titration of an aqueous solution of HC1 with an aqueous solution of NaOH. (Author/EB)

  17. TRIO experiment

    SciTech Connect

    Clemmer, R.G.; Finn, P.A.; Malecha, R.F.; Misra, B.; Billone, M.C.; Bowers, D.L.; Fischer, A.K.; Greenwood, L.R.; Mattas, R.F.; Tam, S.W.

    1984-09-01

    The TRIO experiment is a test of in-situ tritium recovery and heat transfer performance of a miniaturized solid breeder blanket assembly. The assembly (capsule) was monitored for temperature and neutron flux profiles during irradiation and a sweep gas flowed through the capsule to an anaytical train wherein the amounts of tritium in its various chemical forms were determined. The capsule was designed to operate at different temperatures and sweep gas conditions. At the end of the experiment the amount of tritium retained in the solid was at a concentration of less than 0.1 wppM. More than 99.9% of tritium generated during the experiment was successfully recovered. The results of the experiment showed that the tritium inventories at the beginning and at the end of the experiment follow a relationship which appears to be characteristic of intragranular diffusion.

  18. Two Unique Glioma Subtypes Revealed.

    PubMed

    Poh, Alissa

    2016-04-01

    A comprehensive analysis of 1,122 diffuse glioma samples from The Cancer Genome Atlas has revealed two new subtypes of this common brain cancer, with molecular and clinical features that diverge from the norm. The study findings also support the use of DNA methylation profiles to improve glioma classification and treatment.

  19. Ischemic Colitis Revealing Polyarteritis Nodosa

    PubMed Central

    Hamzaoui, Amira; Litaiem, Noureddine; Smiti Khanfir, M.; Ayadi, Sofiene; Nfoussi, Haifa; Houman, M. H.

    2013-01-01

    Ischemic colitis is one of the most common intestinal ischemic injuries. It results from impaired perfusion of blood to the bowel and is rarely caused by vasculitis. We report a case of ischemic colitis revealing polyarteritis nodosa (PAN) in a 55-year-old man. Histological examination of the resected colon led to the diagnosis of PAN. PMID:24382967

  20. Development of catalytic asymmetric 1,4-addition and [3 + 2] cycloaddition reactions using chiral calcium complexes.

    PubMed

    Tsubogo, Tetsu; Saito, Susumu; Seki, Kazutaka; Yamashita, Yasuhiro; Kobayashi, Shu

    2008-10-08

    Catalytic asymmetric 1,4-addition and [3 + 2] cycloaddition reactions using chiral calcium species prepared from calcium isopropoxide and chiral bisoxazoline ligands have been developed. Glycine Schiff bases reacted with acrylic esters to afford 1,4-addition products, glutamic acid derivatives, in high yields with high enantioselectivities. During the investigation of the 1,4-addition reactions, we unexpectedly found that a [3 + 2] cycloaddition occurred in the reactions with crotonate derivatives, affording substituted pyrrolidine derivatives in high yields with high enantioselectivities. On the basis of this finding, we investigated asymmetric [3 + 2] cycloadditions, and it was revealed that several kinds of optically active substituted pyrrolidine derivatives containing contiguous stereogenic tertiary and quaternary carbon centers were obtained with high diastereo- and enantioselectivities. In addition, optically active pyrrolidine cores of hepatitis C virus RNA-dependent polymerase inhibitors and potential effective antiviral agents have been synthesized using this [3 + 2] cycloaddition reaction. NMR spectroscopic analysis and observation of nonamplification of enantioselectivity in nonlinear effect experiments suggested that a monomeric calcium species with an anionic ligand was formed as an active catalyst. A stepwise mechanism of the [3 + 2] cycloaddition, consisting of 1,4-addition and successive intramolecular Mannich-type reaction was suggested. Furthermore, modification of the Schiff base structure resulted in a modification of the reaction course from a [3 + 2] cycloaddition to a 1,4-addition, affording 3-substituted glutamic acid derivatives with high diasterero- and enantioselectivities.

  1. tRNA integrity is a prerequisite for rapid CCA addition: implication for quality control.

    PubMed

    Dupasquier, Marcel; Kim, Sangbumn; Halkidis, Konstantine; Gamper, Howard; Hou, Ya-Ming

    2008-06-06

    CCA addition to the 3' end is an essential step in tRNA maturation. High-resolution crystal structures of the CCA enzymes reveal primary enzyme contact with the tRNA minihelix domain, consisting of the acceptor stem and T stem-loop. RNA and DNA minihelices are efficient substrates for CCA addition in steady-state kinetics. However, in contrast to structural models and steady-state experiments, we show here by single-turnover kinetics that minihelices are insufficient substrates for the Escherichia coli CCA enzyme and that only the full-length tRNA is kinetically competent. Even a nick in the full-length tRNA backbone in the T loop, or as far away from the minihelix domain as in the anticodon loop, prevents efficient CCA addition. These results suggest a kinetic quality control provided by the CCA enzyme to inspect the integrity of the tRNA molecule and to discriminate against nicked or damaged species from further maturation.

  2. Mixture Experiments

    SciTech Connect

    Piepel, Gregory F.

    2007-12-01

    A mixture experiment involves combining two or more components in various proportions or amounts and then measuring one or more responses for the resulting end products. Other factors that affect the response(s), such as process variables and/or the total amount of the mixture, may also be studied in the experiment. A mixture experiment design specifies the combinations of mixture components and other experimental factors (if any) to be studied and the response variable(s) to be measured. Mixture experiment data analyses are then used to achieve the desired goals, which may include (i) understanding the effects of components and other factors on the response(s), (ii) identifying components and other factors with significant and nonsignificant effects on the response(s), (iii) developing models for predicting the response(s) as functions of the mixture components and any other factors, and (iv) developing end-products with desired values and uncertainties of the response(s). Given a mixture experiment problem, a practitioner must consider the possible approaches for designing the experiment and analyzing the data, and then select the approach best suited to the problem. Eight possible approaches include 1) component proportions, 2) mathematically independent variables, 3) slack variable, 4) mixture amount, 5) component amounts, 6) mixture process variable, 7) mixture of mixtures, and 8) multi-factor mixture. The article provides an overview of the mixture experiment designs, models, and data analyses for these approaches.

  3. Overnight lexical consolidation revealed by speech segmentation.

    PubMed

    Dumay, Nicolas; Gareth Gaskell, M

    2012-04-01

    Two experiments explored the consolidation of spoken words, and assessed whether post-sleep novel competitor effects truly reflect engagement of these novel words in competition for lexical segmentation. Two types of competitor relationships were contrasted: the onset-aligned case (such as "frenzylk"), where the novel word is a close variant of the existing word: they start at the same time point and overlap on most of their segments; and the fully embedding case (such as "lirmucktoze"), where the existing word corresponds to a smaller embedded portion of its novel competitor and is thus less noticeable. Experiment 1 (pause detection) revealed a similar performance for both cases, with no competitor effect immediately after exposure, but significant inhibition after 24 h and seven days. Experiment 2 (word spotting) produced exactly the same pattern; however, as is the case with existing word carriers (cf. McQueen, Norris, & Cutler, 1994), the inhibition was much stronger for fully embedded than for onset-aligned targets (e.g., "lirmuckt" vs. "frenzyl"). Meanwhile, explicit measures of learning, i.e., free recall and recognition, improved over time. These results cannot be explained by either consolidation of episodic traces or acquisition of new phonological/dialectal variants. We argue instead that they reflect a general trait of vocabulary learning and consolidation.

  4. Hydronuclear experiments

    SciTech Connect

    Thorn, R.N.; Westervelt, D.R.

    1987-02-01

    Hydronuclear experiments, a method for assessing some aspects of nuclear weapon safety, were conducted at Los Alamos during the 1958 to 1961 moratorium on nuclear testing. The experiments resulted in subcritical multiplying assemblies or a very slight degree of supercriticality and, in some cases, involved a slight, but insignificant, fission energy release. These experiments helped to identify so-called one-point safety problems associated with some of the nuclear weapons systems of that time. The need for remedial action was demonstrated, although some of the necessary design changes could not be made until after the resumption of weapons testing at the end of 1961.

  5. Network Reconstruction Using Nonparametric Additive ODE Models

    PubMed Central

    Henderson, James; Michailidis, George

    2014-01-01

    Network representations of biological systems are widespread and reconstructing unknown networks from data is a focal problem for computational biologists. For example, the series of biochemical reactions in a metabolic pathway can be represented as a network, with nodes corresponding to metabolites and edges linking reactants to products. In a different context, regulatory relationships among genes are commonly represented as directed networks with edges pointing from influential genes to their targets. Reconstructing such networks from data is a challenging problem receiving much attention in the literature. There is a particular need for approaches tailored to time-series data and not reliant on direct intervention experiments, as the former are often more readily available. In this paper, we introduce an approach to reconstructing directed networks based on dynamic systems models. Our approach generalizes commonly used ODE models based on linear or nonlinear dynamics by extending the functional class for the functions involved from parametric to nonparametric models. Concomitantly we limit the complexity by imposing an additive structure on the estimated slope functions. Thus the submodel associated with each node is a sum of univariate functions. These univariate component functions form the basis for a novel coupling metric that we define in order to quantify the strength of proposed relationships and hence rank potential edges. We show the utility of the method by reconstructing networks using simulated data from computational models for the glycolytic pathway of Lactocaccus Lactis and a gene network regulating the pluripotency of mouse embryonic stem cells. For purposes of comparison, we also assess reconstruction performance using gene networks from the DREAM challenges. We compare our method to those that similarly rely on dynamic systems models and use the results to attempt to disentangle the distinct roles of linearity, sparsity, and derivative

  6. Investigation on the Clogging Behavior and Additional Wall Cooling for the Axial-Injection Cold Spray Nozzle

    NASA Astrophysics Data System (ADS)

    Wang, Xudong; Zhang, Bo; Lv, Jinsheng; Yin, Shuo

    2015-04-01

    During the cold spray process, nozzle clogging always happens when spraying low-melting point materials, e.g., aluminum, significantly decreasing the working efficiency. In this paper, a comprehensive investigation was carried out to clarify the reason for inducing nozzle clogging and then to evaluate a home-made nozzle cooling device for preventing nozzle clogging. Computational fluid dynamics technique was employed as the main method with some necessary experiment validation. It is found that the particle dispersion and the high-temperature nozzle wall at the near-throat region are two dominant factors that cause nozzle clogging. The numerical results also reveal that the home-made cooling device can significantly reduce the nozzle wall temperature, which was validated by the experimental measurement. Besides, the aluminum coating build-up experiment further indicates that the additional cooling device can truly prevent the nozzle clogging.

  7. Interpretive Experiments

    ERIC Educational Resources Information Center

    DeHaan, Frank, Ed.

    1977-01-01

    Describes an interpretative experiment involving the application of symmetry and temperature-dependent proton and fluorine nmr spectroscopy to the solution of structural and kinetic problems in coordination chemistry. (MLH)

  8. Wanted: Experiments

    ERIC Educational Resources Information Center

    McDaniel, Floyd D.

    1974-01-01

    Describes a project to produce a series of laboratory manuals and instructional materials in which nuclear experiments are presented for the undergraduate advanced laboratory. The manuals are being compiled in the areas of physics, chemistry, geology and environmental sciences. (BR)

  9. ADHD Diet: Do Food Additives Cause Hyperactivity?

    MedlinePlus

    ... There's no solid evidence that food additives cause attention-deficit/hyperactivity disorder (ADHD). However, the topic of food additives and their possible effects is controversial. Some studies indicate that certain food ...

  10. Additive Manufacturing of Aerospace Propulsion Components

    NASA Technical Reports Server (NTRS)

    Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

    2015-01-01

    The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

  11. [Safety of food additives in Japan].

    PubMed

    Ito, Sumio

    2011-01-01

    Recently, many accidents relating to food happened in Japan. The consumer's distrust for food, food companies, and the administration is increasing. The consumer especially has an extreme refusal feeling for chemicals such as food additives and agricultural chemicals, and begins to request agricultural chemical-free vegetables and food additive-free food. Food companies also state no agricultural chemicals and no food additives to correspond with consumers' request and aim at differentiating. The food additive is that the Ministry of Health, Labour and Welfare specifies the one that person's health might not be ruined by providing for Food Sanitation Law Article 10 in our country. The standard for food additives and standard for use of food additives are provided according to regulations of Food Sanitation Law Article 11. Therefore, it is thought that the food additive used is safe now. Then, it reports on the procedure and the safety examination, etc. in our country for designation for food additive this time.

  12. Additive-driven assembly of block copolymers

    NASA Astrophysics Data System (ADS)

    Lin, Ying; Daga, Vikram; Anderson, Eric; Watkins, James

    2011-03-01

    One challenge to the formation of well ordered hybrid materials is the incorporation of nanoscale additives including metal, semiconductor and dielectric nanoparticles at high loadings while maintaining strong segregation. Here we describe the molecular and functional design of small molecule and nanoparticle additives that enhance phase segregation in their block copolymer host and enable high additive loadings. Our approach includes the use of hydrogen bond interactions between the functional groups on the additive or particle that serve as hydrogen bond donors and one segment of the block copolymer containing hydrogen bond acceptors. Further, the additives show strong selectively towards the targeted domains, leading to enhancements in contrast between properties of the phases. In addition to structural changes, we explore how large changes in the thermal and mechanical properties occur upon incorporation of the additives. Generalization of this additive-induced ordering strategy to various block copolymers will be discussed.

  13. Modeling uranium transport in acidic contaminated groundwater with base addition.

    PubMed

    Zhang, Fan; Luo, Wensui; Parker, Jack C; Brooks, Scott C; Watson, David B; Jardine, Philip M; Gu, Baohua

    2011-06-15

    This study investigates reactive transport modeling in a column of uranium(VI)-contaminated sediments with base additions in the circulating influent. The groundwater and sediment exhibit oxic conditions with low pH, high concentrations of NO(3)(-), SO(4)(2-), U and various metal cations. Preliminary batch experiments indicate that additions of strong base induce rapid immobilization of U for this material. In the column experiment that is the focus of the present study, effluent groundwater was titrated with NaOH solution in an inflow reservoir before reinjection to gradually increase the solution pH in the column. An equilibrium hydrolysis, precipitation and ion exchange reaction model developed through simulation of the preliminary batch titration experiments predicted faster reduction of aqueous Al than observed in the column experiment. The model was therefore modified to consider reaction kinetics for the precipitation and dissolution processes which are the major mechanism for Al immobilization. The combined kinetic and equilibrium reaction model adequately described variations in pH, aqueous concentrations of metal cations (Al, Ca, Mg, Sr, Mn, Ni, Co), sulfate and U(VI). The experimental and modeling results indicate that U(VI) can be effectively sequestered with controlled base addition due to sorption by slowly precipitated Al with pH-dependent surface charge. The model may prove useful to predict field-scale U(VI) sequestration and remediation effectiveness.

  14. [Seizures revealing phosphocalcic metabolism abnormalities].

    PubMed

    Hmami, F; Chaouki, S; Benmiloud, S; Souilmi, F Z; Abourazzak, S; Idrissi, M; Atmani, S; Bouharrou, A; Hida, M

    2014-01-01

    Hypocalcemia due to hypoparathyroidism produces a broad spectrum of clinical manifestations, but overt symptoms may be sparse. One unusual presentation is onset or aggravation of epilepsy in adolescence revealing hypoparathyroidism. This situation can lead to delayed diagnosis, with inefficacity of the antiepileptic drugs. We report five cases of adolescence-onset epilepsy with unsuccessful antiepileptic therapy, even with gradually increasing dose. Physical examination revealed signs of hypocalcemia, confirmed biologically. Full testing disclosed the origin of the seizures: hypoparathyroidism in three patients and pseudohypoparathyroidism in the other two. In four of five patients, computed tomography showed calcification of the basal ganglia, defining Fahr's syndrome. The patients were treated with oral calcium and active vitamin D (1-alphahydroxy vitamin D3). Seizure frequency progressively decreased and serum calcium levels returned to normal. These cases illustrate the importance of the physical examination and of routine serum calcium assay in patients with new-onset epileptic seizures in order to detect hypocalcemia secondary to hypoparathyroidism.

  15. Revealing the microstructure of materials

    NASA Technical Reports Server (NTRS)

    Nelson, James A.

    1990-01-01

    The objectives are to demonstrate how the microstructure of materials may be revealed by abrasive polishing and chemical etching, and to illustrate how microstructural information is used to monitor manufacturing processes, provide in-depth inspection, and perform failure analysis. Microstructural analysis is the procedure used to reveal the internal microstructural details of a material or part by sectioning and polishing the cut surface so that it may be examined under a suitable microscope. A printed wiring board was selected as the test material because it contains both metals and nonmetals that have distinctive microstructures, and because this technique is used throughout the electronic industry as a key quality control tool. The three principle component materials in printed circuit boards are glass/epoxy laminates faced with copper foil; copper, deposited by both electroless and electrolytic plating; and tin/lead solder. Sample preparation, mounting, grinding, polishing, and examination and analysis are discussed.

  16. 7 CFR 1944.686 - Additional grants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 13 2011-01-01 2009-01-01 true Additional grants. 1944.686 Section 1944.686...) PROGRAM REGULATIONS (CONTINUED) HOUSING Housing Preservation Grants § 1944.686 Additional grants. An additional HPG grant may be made when the grantee has achieved or nearly achieved the goals established...

  17. 7 CFR 1944.545 - Additional grants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 13 2013-01-01 2013-01-01 false Additional grants. 1944.545 Section 1944.545...) PROGRAM REGULATIONS (CONTINUED) HOUSING Technical and Supervisory Assistance Grants § 1944.545 Additional grants. An additional grant may be made to an applicant that has previously received a TSA grant and...

  18. 7 CFR 1944.545 - Additional grants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 13 2011-01-01 2009-01-01 true Additional grants. 1944.545 Section 1944.545...) PROGRAM REGULATIONS (CONTINUED) HOUSING Technical and Supervisory Assistance Grants § 1944.545 Additional grants. An additional grant may be made to an applicant that has previously received a TSA grant and...

  19. 7 CFR 1944.686 - Additional grants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 13 2013-01-01 2013-01-01 false Additional grants. 1944.686 Section 1944.686...) PROGRAM REGULATIONS (CONTINUED) HOUSING Housing Preservation Grants § 1944.686 Additional grants. An additional HPG grant may be made when the grantee has achieved or nearly achieved the goals established...

  20. 7 CFR 1944.545 - Additional grants.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 13 2010-01-01 2009-01-01 true Additional grants. 1944.545 Section 1944.545...) PROGRAM REGULATIONS (CONTINUED) HOUSING Technical and Supervisory Assistance Grants § 1944.545 Additional grants. An additional grant may be made to an applicant that has previously received a TSA grant and...

  1. 10 CFR 55.7 - Additional requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Additional requirements. 55.7 Section 55.7 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) OPERATORS' LICENSES General Provisions § 55.7 Additional requirements. The Commission may, by rule, regulation, or order, impose upon any licensee such requirements, in addition...

  2. Polymeric Additives For Graphite/Epoxy Composites

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.; Nir, Z.

    1990-01-01

    Report describes experimental studies of properties of several graphite/epoxy composites containing polymeric additives as flexibilizing or toughening agents. Emphasizes effects of brominated polymeric additives (BPA's) with or without carboxy-terminated butadiene acrylonitrile rubber. Reviews effects of individual and combined additives on fracture toughnesses, environmental stabilities, hot/wet strengths, thermomechanical behaviors, and other mechanical properties of composites.

  3. 10 CFR 55.7 - Additional requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Additional requirements. 55.7 Section 55.7 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) OPERATORS' LICENSES General Provisions § 55.7 Additional requirements. The Commission may, by rule, regulation, or order, impose upon any licensee such requirements, in addition...

  4. 14 CFR 27.927 - Additional tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Additional tests. 27.927 Section 27.927... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.927 Additional tests. (a) Any additional dynamic, endurance, and operational tests, and vibratory investigations necessary to...

  5. 14 CFR 29.927 - Additional tests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Additional tests. 29.927 Section 29.927... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.927 Additional tests. (a) Any additional dynamic, endurance, and operational tests, and vibratory investigations necessary to...

  6. 14 CFR 27.927 - Additional tests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Additional tests. 27.927 Section 27.927... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.927 Additional tests. (a) Any additional dynamic, endurance, and operational tests, and vibratory investigations necessary to...

  7. 14 CFR 27.927 - Additional tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Additional tests. 27.927 Section 27.927... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.927 Additional tests. (a) Any additional dynamic, endurance, and operational tests, and vibratory investigations necessary to...

  8. 14 CFR 29.927 - Additional tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Additional tests. 29.927 Section 29.927... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.927 Additional tests. (a) Any additional dynamic, endurance, and operational tests, and vibratory investigations necessary to...

  9. 14 CFR 29.927 - Additional tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Additional tests. 29.927 Section 29.927... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.927 Additional tests. (a) Any additional dynamic, endurance, and operational tests, and vibratory investigations necessary to...

  10. 17 CFR 48.10 - Additional contracts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 2 2014-04-01 2014-04-01 false Additional contracts. 48.10...) REGISTRATION OF FOREIGN BOARDS OF TRADE § 48.10 Additional contracts. (a) Generally. A registered foreign board of trade that wishes to make an additional futures, option or swap contract available for trading...

  11. 17 CFR 48.10 - Additional contracts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 1 2013-04-01 2013-04-01 false Additional contracts. 48.10... FOREIGN BOARDS OF TRADE § 48.10 Additional contracts. (a) Generally. A registered foreign board of trade that wishes to make an additional futures, option or swap contract available for trading by...

  12. 12 CFR 615.5460 - Additional provisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Additional provisions. 615.5460 Section 615.5460 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM FUNDING AND FISCAL AFFAIRS, LOAN... Additional provisions. (a) Additional requirements. In any case or any class of cases arising under...

  13. 46 CFR 355.5 - Additional material.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false Additional material. 355.5 Section 355.5 Shipping... STATES CITIZENSHIP § 355.5 Additional material. If additional material is determined to be essential to clarify or support the evidence of U.S. citizenship, such material shall be furnished by...

  14. 7 CFR 1944.545 - Additional grants.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 13 2012-01-01 2012-01-01 false Additional grants. 1944.545 Section 1944.545...) PROGRAM REGULATIONS (CONTINUED) HOUSING Technical and Supervisory Assistance Grants § 1944.545 Additional grants. An additional grant may be made to an applicant that has previously received a TSA grant and...

  15. 7 CFR 1944.686 - Additional grants.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 13 2012-01-01 2012-01-01 false Additional grants. 1944.686 Section 1944.686...) PROGRAM REGULATIONS (CONTINUED) HOUSING Housing Preservation Grants § 1944.686 Additional grants. An additional HPG grant may be made when the grantee has achieved or nearly achieved the goals established...

  16. 7 CFR 1944.545 - Additional grants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 13 2014-01-01 2013-01-01 true Additional grants. 1944.545 Section 1944.545...) PROGRAM REGULATIONS (CONTINUED) HOUSING Technical and Supervisory Assistance Grants § 1944.545 Additional grants. An additional grant may be made to an applicant that has previously received a TSA grant and...

  17. 7 CFR 1944.686 - Additional grants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 13 2014-01-01 2013-01-01 true Additional grants. 1944.686 Section 1944.686...) PROGRAM REGULATIONS (CONTINUED) HOUSING Housing Preservation Grants § 1944.686 Additional grants. An additional HPG grant may be made when the grantee has achieved or nearly achieved the goals established...

  18. 46 CFR 355.5 - Additional material.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Additional material. 355.5 Section 355.5 Shipping... STATES CITIZENSHIP § 355.5 Additional material. If additional material is determined to be essential to clarify or support the evidence of U.S. citizenship, such material shall be furnished by...

  19. 46 CFR 355.5 - Additional material.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Additional material. 355.5 Section 355.5 Shipping... STATES CITIZENSHIP § 355.5 Additional material. If additional material is determined to be essential to clarify or support the evidence of U.S. citizenship, such material shall be furnished by...

  20. 46 CFR 355.5 - Additional material.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Additional material. 355.5 Section 355.5 Shipping... STATES CITIZENSHIP § 355.5 Additional material. If additional material is determined to be essential to clarify or support the evidence of U.S. citizenship, such material shall be furnished by...

  1. 5 CFR 841.1006 - Additional provisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Additional provisions. 841.1006 Section....1006 Additional provisions. These additional provisions are also binding on the State and OPM: (a) A... will issue an accounting. If the State finds this accounting unacceptable, it may then and only...

  2. 5 CFR 831.1905 - Additional provisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Additional provisions. 831.1905 Section... (CONTINUED) RETIREMENT State Income Tax Withholding § 831.1905 Additional provisions. These additional provisions are also binding on the State and OPM: (a) A request or revocation is effective when processed...

  3. The Experiment

    NASA Astrophysics Data System (ADS)

    Mariana Nicoara, Floare

    2016-04-01

    My name is Nicoara Floarea and I am teacher at Secondary School Calatele and I teach students from preparatory class and the second grade . They are six-eight years old. In my activity, for introducing scientific concepts to my students, I use various and active methods or traditional methods including experiments. The experiment stimulates students' curiosity, their creativity, the understanding and knowledge taught accessibility. I propose you two such experiments: The life cycle of the plants (long-term experiment, with rigorous observation time):We use beans, wheat or other; They are grown in pots and on the cotton soaked with water,keeping under students' observation protecting them ( just soak them regularly) and we waiting the plants rise. For discussions and comments of plant embryo development we use the plants which rose on the cotton soaked with water plants at the end of the first week. Last school year we had in the pot climbing beans which in May made pods. They were not too great but our experiment was a success. The students could deduce that there will develop those big beans which after drying will be planted again. The influence of light on plants (average duration experiment with the necessary observation time): We use two pots in which plants are of the same type (two geraniums), one of them is situated so as to get direct sunlight and other plant we put in a closed box. Although we wet both plants after a week we see that the plant that benefited from sunlight has turned strain in direct sunlight, developing normally in return the plant out of the box I have yellowed leaves, photosynthesis does not She has occurred . Students will understand the vital role of the Sun in plants' life, both in the classroom and in nature. The experiment is a method of teaching students extremely pleasant, with a remarkable percentage of acquiring more knowledge.

  4. Metal-Polycyclic Aromatic Hydrocarbon Mixture Toxicity in Hyalella azteca. 1. Response Surfaces and Isoboles To Measure Non-additive Mixture Toxicity and Ecological Risk.

    PubMed

    Gauthier, Patrick T; Norwood, Warren P; Prepas, Ellie E; Pyle, Greg G

    2015-10-06

    Mixtures of metals and polycyclic aromatic hydrocarbons (PAHs) occur ubiquitously in aquatic environments, yet relatively little is known regarding their potential to produce non-additive toxicity (i.e., antagonism or potentiation). A review of the lethality of metal-PAH mixtures in aquatic biota revealed that more-than-additive lethality is as common as strictly additive effects. Approaches to ecological risk assessment do not consider non-additive toxicity of metal-PAH mixtures. Forty-eight-hour water-only binary mixture toxicity experiments were conducted to determine the additive toxic nature of mixtures of Cu, Cd, V, or Ni with phenanthrene (PHE) or phenanthrenequinone (PHQ) using the aquatic amphipod Hyalella azteca. In cases where more-than-additive toxicity was observed, we calculated the possible mortality rates at Canada's environmental water quality guideline concentrations. We used a three-dimensional response surface isobole model-based approach to compare the observed co-toxicity in juvenile amphipods to predicted outcomes based on concentration addition or effects addition mixtures models. More-than-additive lethality was observed for all Cu-PHE, Cu-PHQ, and several Cd-PHE, Cd-PHQ, and Ni-PHE mixtures. Our analysis predicts Cu-PHE, Cu-PHQ, Cd-PHE, and Cd-PHQ mixtures at the Canadian Water Quality Guideline concentrations would produce 7.5%, 3.7%, 4.4% and 1.4% mortality, respectively.

  5. Experiment 2042

    SciTech Connect

    Dash, Zora V.; Dennis, Bert R.; Dreesen, Donald S.; Fehler, Michael C.; House, Leigh S.; Walter, Fritz; Zyvoloski, George A.

    1984-09-10

    Experiment 2042, an injection test in EE-3, was conducted from May 15, 1984 through May 19, 1984. During this four day test ~2 million gallons of water were injected with a maximum injection rate of ~10BPM at 6000 psi. It was planned as a pumping test of the lower zone of well EE-3 (the open hole region from 11,400 ft to 11,648 ft) to test the reservoir characteristics and fracture-seismic system first created during Experiment 2025. However early in the experiment it became apparent that there was some sort connection between the lower zone and the upper "low pressure" zone in EE-3 (from the casing shoe at 10374 ft to about 10900 ft). Available information ruled out a packer failure or other direct connection between these zones so the experiment was continued as planned. Although not a major goal of the experiment, it was hoped that fractures would propagate from EE-3 to EE-2, so hydraulic communication could be established between the two wells, however this did not occur.

  6. ADME-Tox profiles of some food additives and pesticides

    NASA Astrophysics Data System (ADS)

    Craciun, Dana; Modra, Dorina; Isvoran, Adriana

    2015-12-01

    Within this study we compute the Absorption, Distribution, Metabolism, Excretion and Toxicity (ADME-Tox) profiles of several commonly used food additives and some pesticides. As expected, all the food additives considered in this study provided to be safe, their ADME-Tox profiles indicating that they have a good oral bioavailability and they do not produce phosphoslipidosis. The ADME-Tox profiles of the pesticides indicate that, with a few exceptions, they are highly toxic (some of them being not approved in the EU, but still used in other countries) and may cause many diseases. Our results are in good agreement with published data concerning the considered food additives and pesticides revealing that the ADME-Tox profiling method may be successfully used to test other chemicals than drug candidates.

  7. Influence of boric acid additive size on green lubricant performance.

    PubMed

    Lovell, Michael R; Kabir, M A; Menezes, Pradeep L; Higgs, C Fred

    2010-10-28

    As the industrial community moves towards green manufacturing processes, there is an increased demand for multi-functional, environmentally friendly lubricants with enhanced tribological performance. In the present investigation, green (environmentally benign) lubricant combinations were prepared by homogeneously mixing nano- (20 nm), sub-micrometre- (600 nm average size) and micrometre-scale (4 μm average size) boric acid powder additives with canola oil in a vortex generator. As a basis for comparison, lubricants of base canola oil and canola oil mixed with MoS(2) powder (ranging from 0.5 to 10 μm) were also prepared. Friction and wear experiments were carried out on the prepared lubricants using a pin-on-disc apparatus under ambient conditions. Based on the experiments, the nanoscale (20 nm) particle boric acid additive lubricants significantly outperformed all of the other lubricants with respect to frictional and wear performance. In fact, the nanoscale boric acid powder-based lubricants exhibited a wear rate more than an order of magnitude lower than the MoS(2) and larger sized boric acid additive-based lubricants. It was also discovered that the oil mixed with a combination of sub-micrometre- and micrometre-scale boric acid powder additives exhibited better friction and wear performance than the canola oil mixed with sub-micrometre- or micrometre-scale boric acid additives alone.

  8. 21 CFR 70.42 - Criteria for evaluating the safety of color additives.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... additives. 70.42 Section 70.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a color additive whether he believes the experiments planned will yield data adequate for...

  9. 21 CFR 70.42 - Criteria for evaluating the safety of color additives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... additives. 70.42 Section 70.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a color additive whether he believes the experiments planned will yield data adequate for...

  10. 21 CFR 70.42 - Criteria for evaluating the safety of color additives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... additives. 70.42 Section 70.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a color additive whether he believes the experiments planned will yield data adequate for...

  11. 21 CFR 70.42 - Criteria for evaluating the safety of color additives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... additives. 70.42 Section 70.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a color additive whether he believes the experiments planned will yield data adequate for...

  12. 21 CFR 70.42 - Criteria for evaluating the safety of color additives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... additives. 70.42 Section 70.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... experiments to determine its safety, the Commissioner will advise a person who wishes to establish the safety of a color additive whether he believes the experiments planned will yield data adequate for...

  13. Changes in sexual experiences and relationship quality during pregnancy.

    PubMed

    Sagiv-Reiss, Dafna M; Birnbaum, Gurit E; Safir, Marilyn P

    2012-10-01

    The present research examined changes in sexuality and relationship quality during pregnancy. In three studies, participants completed self-report scales of sex-related emotions, thoughts, motives, and experiences, as well as relationship quality. Study 1 (N = 361) examined the differences between pregnant and non-pregnant women in sexual and relational experiences. Study 2 (N = 25) monitored women's sexuality and relationship quality throughout the three trimesters of pregnancy. Study 3 examined gender differences in changes in sexual and relational experiences during the second and third trimesters of pregnancy among 31 cohabiting couples. The findings revealed that pregnant women were more sexually motivated by relational concerns than both their partners and non-pregnant women. Additionally, the results pointed to the involvement of two corresponding processes: Sexual enjoyment declined as pregnancy progressed, whereas relational satisfaction was relatively unchanged during pregnancy. These findings suggest that the progress of pregnancy may independently affect sexuality and relational quality.

  14. A global analysis of soil acidification caused by nitrogen addition

    NASA Astrophysics Data System (ADS)

    Tian, Dashuan; Niu, Shuli

    2015-02-01

    Nitrogen (N) deposition-induced soil acidification has become a global problem. However, the response patterns of soil acidification to N addition and the underlying mechanisms remain far from clear. Here, we conducted a meta-analysis of 106 studies to reveal global patterns of soil acidification in responses to N addition. We found that N addition significantly reduced soil pH by 0.26 on average globally. However, the responses of soil pH varied with ecosystem types, N addition rate, N fertilization forms, and experimental durations. Soil pH decreased most in grassland, whereas boreal forest was not observed a decrease to N addition in soil acidification. Soil pH decreased linearly with N addition rates. Addition of urea and NH4NO3 contributed more to soil acidification than NH4-form fertilizer. When experimental duration was longer than 20 years, N addition effects on soil acidification diminished. Environmental factors such as initial soil pH, soil carbon and nitrogen content, precipitation, and temperature all influenced the responses of soil pH. Base cations of Ca2+, Mg2+ and K+ were critical important in buffering against N-induced soil acidification at the early stage. However, N addition has shifted global soils into the Al3+ buffering phase. Overall, this study indicates that acidification in global soils is very sensitive to N deposition, which is greatly modified by biotic and abiotic factors. Global soils are now at a buffering transition from base cations (Ca2+, Mg2+ and K+) to non-base cations (Mn2+ and Al3+). This calls our attention to care about the limitation of base cations and the toxic impact of non-base cations for terrestrial ecosystems with N deposition.

  15. Molecular Aluminum Additive for Burn Enhancement of Hydrocarbon Fuels.

    PubMed

    Guerieri, Philip M; DeCarlo, Samantha; Eichhorn, Bryan; Connell, Terrence; Yetter, Richard A; Tang, Xin; Hicks, Zachary; Bowen, Kit H; Zachariah, Michael R

    2015-11-12

    Additives to hydrocarbon fuels are commonly explored to change the combustion dynamics, chemical distribution, and/or product integrity. Here we employ a novel aluminum-based molecular additive, Al(I) tetrameric cluster [AlBrNEt3]4 (Et = C2H5), to a hydrocarbon fuel and evaluate the resultant single-droplet combustion properties. This Al4 cluster offers a soluble alternative to nanoscale particulate additives that have recently been explored and may mitigate the observed problems of particle aggregation. Results show the [AlBrNEt3]4 additive to increase the burn rate constant of a toluene-diethyl ether fuel mixture by ∼20% in a room temperature oxygen environment with only 39 mM of active aluminum additive (0.16 wt % limited by additive solubility). In comparison, a roughly similar addition of nano-aluminum particulate shows no discernible difference in burn properties of the hydrocarbon fuel. High speed video shows the [AlBrNEt3]4 to induce microexplosive gas release events during the last ∼30% of the droplet combustion time. We attribute this to HBr gas release based on results of temperature-programmed reaction (TPR) experiments of the [AlBrNEt3]4 dosed with O2 and D2O. A possible mechanism of burn rate enhancement is presented that is consistent with microexplosion observations and TPR results.

  16. Metal hydride and pyrophoric fuel additives for dicyclopentadiene based hybrid propellants

    NASA Astrophysics Data System (ADS)

    Shark, Steven C.

    The purpose of this study is to investigate the use of reactive energetic fuel additives that have the potential to increase the combustion performance of hybrid rocket propellants in terms of solid fuel regression rate and combustion efficiency. Additives that can augment the combustion flame zone in a hybrid rocket motor by means of increased energy feedback to the fuel grain surface are of great interest. Metal hydrides have large volumetric hydrogen densities, which gives these materials high performance potential as fuel additives in terms of specifc impulse. The excess hydrogen and corresponding base metal may also cause an increase in the hybrid rocket solid fuel regression rate. Pyrophoric additives also have potential to increase the solid fuel regression rate by reacting more readily near the burning fuel surface providing rapid energy feedback. An experimental performance evaluation of metal hydride fuel additives for hybrid rocket motor propulsion systems is examined in this study. Hypergolic ignition droplet tests and an accelerated aging study revealed the protection capabilities of Dicyclopentadiene (DCPD) as a fuel binder, and the ability for unaided ignition. Static hybrid rocket motor experiments were conducted using DCPD as the fuel. Sodium borohydride (NabH4) and aluminum hydride (AlH3) were examined as fuel additives. Ninety percent rocket grade hydrogen peroxide (RGHP) was used as the oxidizer. In this study, the sensitivity of solid fuel regression rate and characteristic velocity (C*) efficiency to total fuel grain port mass flux and particle loading is examined. These results were compared to HTPB combustion performance as a baseline. Chamber pressure histories revealed steady motor operation in most tests, with reduced ignition delays when using NabH4 as a fuel additive. The addition of NabH4 and AlH3 produced up to a 47% and 85% increase in regression rate over neat DCPD, respectively. For all test conditions examined C* efficiency ranges

  17. Neutrino Experiments

    SciTech Connect

    McKeown, R. D.

    2010-08-04

    Recent studies of neutrino oscillations have established the existence of finite neutrino masses and mixing between generations of neutrinos. The combined results from studies of atmospheric neutrinos, solar neutrinos, reactor antineutrinos and neutrinos produced at accelerators paint an intriguing picture that clearly requires modification of the standard model of particle physics. These results also provide clear motivation for future neutrino oscillation experiments as well as searches for direct neutrino mass and nuclear double-beta decay. I will discuss the program of new neutrino oscillation experiments aimed at completing our knowledge of the neutrino mixing matrix.

  18. Revealing effective classifiers through network comparison

    NASA Astrophysics Data System (ADS)

    Gallos, Lazaros K.; Fefferman, Nina H.

    2014-11-01

    The ability to compare complex systems can provide new insight into the fundamental nature of the processes captured, in ways that are otherwise inaccessible to observation. Here, we introduce the n-tangle method to directly compare two networks for structural similarity, based on the distribution of edge density in network subgraphs. We demonstrate that this method can efficiently introduce comparative analysis into network science and opens the road for many new applications. For example, we show how the construction of a “phylogenetic tree” across animal taxa according to their social structure can reveal commonalities in the behavioral ecology of the populations, or how students create similar networks according to the University size. Our method can be expanded to study many additional properties, such as network classification, changes during time evolution, convergence of growth models, and detection of structural changes during damage.

  19. Nitrogen as a friendly addition to steel

    SciTech Connect

    Rawers, J.C.

    2006-01-01

    Interstitial alloying with nitrogen or carbon is a common means of enhancing properties of iron-based alloys. Interstitial nitrogen addition to fcc-phase Fe-Cr-Mn/Ni alloys results in improved mechanical properties, whereas addition of carbon can result in the formation of unwanted carbides. Carbon addition to low alloy, bcc-phase iron alloys significantly improves strength through the formation of carbides, whereas addition of nitrogen in bcc-phase iron alloys can result in porous casting and reduced mechanical properties. This study will show that alloying iron-based alloys with both nitrogen and carbon can produce positive results. Nitrogen addition to Fe-C and Fe-Cr-C alloys, and both nitrogen and nitrogen-carbon additions to Fe-Cr-Mn/Ni alloys altered the microstructure, improved mechanical properties, increased hardness, and reduced wear by stabilizing the fcc-phase and altering (possibly eliminating) precipitate formation.

  20. HEGRA Experiment

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    The La Palma cosmic-ray observatory HEGRA (High-Energy Gamma-Ray Astronomy) is an air shower experiment, located at the OBSERVATORIO DEL ROQUE DE LOS MUCHACHOS (2200 m above sea level, 28.75°N, 17.89°W) on the Canary island of La Palma, and is operated by institutes from Germany, Spain and Yerevan....

  1. Cincinnati Big Area Additive Manufacturing (BAAM)

    SciTech Connect

    Duty, Chad E.; Love, Lonnie J.

    2015-03-04

    Oak Ridge National Laboratory (ORNL) worked with Cincinnati Incorporated (CI) to demonstrate Big Area Additive Manufacturing which increases the speed of the additive manufacturing (AM) process by over 1000X, increases the size of parts by over 10X and shows a cost reduction of over 100X. ORNL worked with CI to transition the Big Area Additive Manufacturing (BAAM) technology from a proof-of-principle (TRL 2-3) demonstration to a prototype product stage (TRL 7-8).

  2. Revealing the Effects of Cognitive Education Programmes through Dynamic Assessment

    ERIC Educational Resources Information Center

    Tzuriel, David

    2011-01-01

    The major objective of this paper is to demonstrate the effectiveness of dynamic assessment (DA) in revealing outcomes of cognitive education programmes. Three programmes based on "mediated learning experience" theory are reviewed: "Feuerstein's Instrumental Enrichment", "Bright Start", and "Peer Mediation with…

  3. An additional substrate binding site in a bacterial phenylalanine hydroxylase.

    PubMed

    Ronau, Judith A; Paul, Lake N; Fuchs, Julian E; Corn, Isaac R; Wagner, Kyle T; Liedl, Klaus R; Abu-Omar, Mahdi M; Das, Chittaranjan

    2013-09-01

    Phenylalanine hydroxylase (PAH) is a non-heme iron enzyme that catalyzes oxidation of phenylalanine to tyrosine, a reaction that must be kept under tight regulatory control. Mammalian PAH has a regulatory domain in which binding of the substrate leads to allosteric activation of the enzyme. However, the existence of PAH regulation in evolutionarily distant organisms, for example some bacteria in which it occurs, has so far been underappreciated. In an attempt to crystallographically characterize substrate binding by PAH from Chromobacterium violaceum, a single-domain monomeric enzyme, electron density for phenylalanine was observed at a distal site 15.7 Å from the active site. Isothermal titration calorimetry (ITC) experiments revealed a dissociation constant of 24 ± 1.1 μM for phenylalanine. Under the same conditions, ITC revealed no detectable binding for alanine, tyrosine, or isoleucine, indicating the distal site may be selective for phenylalanine. Point mutations of amino acid residues in the distal site that contact phenylalanine (F258A, Y155A, T254A) led to impaired binding, consistent with the presence of distal site binding in solution. Although kinetic analysis revealed that the distal site mutants suffer discernible loss of their catalytic activity, X-ray crystallographic analysis of Y155A and F258A, the two mutants with the most noticeable decrease in activity, revealed no discernible change in the structure of their active sites, suggesting that the effect of distal binding may result from protein dynamics in solution.

  4. 42 CFR 67.22 - Additional conditions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... AGENCY FOR HEALTH CARE POLICY AND RESEARCH GRANTS AND CONTRACTS Research Grants for Health Services Research, Evaluation, Demonstration, and Dissemination Projects § 67.22 Additional conditions....

  5. Selection of color additives: a regulatory view.

    PubMed

    Kumar, Anuj; Dureja, Harish; Madan, Anil K

    2012-01-01

    Color additives have a unique place in the categories of the excipients. However, most of the color additives are complex heterogeneous organic compounds. In pharmaceuticals, colors are used in various oral (solid, liquid) and topical dosage form. Different regulatory authorities have their own specific set of regulation for registration, approval, and control of color additives. However, at this time of globalization, selection of appropriate color is not an easy task when a company wants to sale its product in many countries. In this article, the authors have explored various important factors which should be considered in the selection of color additives.

  6. Allergic and immunologic reactions to food additives.

    PubMed

    Gultekin, Fatih; Doguc, Duygu Kumbul

    2013-08-01

    For centuries, food additives have been used for flavouring, colouring and extension of the useful shelf life of food, as well as the promotion of food safety. During the last 20 years, the studies implicating the additives contained in foods and medicine as a causative factor of allergic reactions have been proliferated considerably. In this review, we aimed to overview all of the food additives which were approved to consume in EU and find out how common and serious allergic reactions come into existence following the consuming of food additives.

  7. Classification of additives for organic photovoltaic devices.

    PubMed

    Machui, Florian; Maisch, Philipp; Burgués-Ceballos, Ignasi; Langner, Stefan; Krantz, Johannes; Ameri, Tayebeh; Brabec, Christoph J

    2015-04-27

    The use of additives to improve the performance of organic photovoltaic cells has been intensely researched in recent years. However, so far, no system has been reported for the classification of additives and their functions. In this report, a system for classifying additives according to the fundamental mechanism by which they influence microstructure formation for P3HT:PCBM is suggested. The major parameters used for their classification are solubility and drying kinetics. Both are discussed in detail and their consequences on processing are analyzed. Furthermore, a general mechanism to classify the impact of additives on structure formation is suggested and discussed for different materials relevant to organic photovoltaic devices.

  8. 47 CFR 5.311 - Additional requirements related to safety of the public.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... safety of the public. In addition to the notification requirements of § 5.309, for experiments that may... bands and geographic area as the planned experiment and, as appropriate, their end users; (b) Rapid identification, and elimination, of any harm the experiment may cause; and (c) Identifying an alternate means...

  9. 47 CFR 5.311 - Additional requirements related to safety of the public.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... safety of the public. In addition to the notification requirements of § 5.309, for experiments that may... bands and geographic area as the planned experiment and, as appropriate, their end users; (b) Rapid identification, and elimination, of any harm the experiment may cause; and (c) Identifying an alternate means...

  10. 3D printed microfluidic circuitry via multijet-based additive manufacturing†

    PubMed Central

    Sochol, R. D.; Sweet, E.; Glick, C. C.; Venkatesh, S.; Avetisyan, A.; Ekman, K. F.; Raulinaitis, A.; Tsai, A.; Wienkers, A.; Korner, K.; Hanson, K.; Long, A.; Hightower, B. J.; Slatton, G.; Burnett, D. C.; Massey, T. L.; Iwai, K.; Lee, L. P.; Pister, K. S. J.; Lin, L.

    2016-01-01

    The miniaturization of integrated fluidic processors affords extensive benefits for chemical and biological fields, yet traditional, monolithic methods of microfabrication present numerous obstacles for the scaling of fluidic operators. Recently, researchers have investigated the use of additive manufacturing or “three-dimensional (3D) printing” technologies – predominantly stereolithography – as a promising alternative for the construction of submillimeter-scale fluidic components. One challenge, however, is that current stereolithography methods lack the ability to simultaneously print sacrificial support materials, which limits the geometric versatility of such approaches. In this work, we investigate the use of multijet modelling (alternatively, polyjet printing) – a layer-by-layer, multi-material inkjetting process – for 3D printing geometrically complex, yet functionally advantageous fluidic components comprised of both static and dynamic physical elements. We examine a fundamental class of 3D printed microfluidic operators, including fluidic capacitors, fluidic diodes, and fluidic transistors. In addition, we evaluate the potential to advance on-chip automation of integrated fluidic systems via geometric modification of component parameters. Theoretical and experimental results for 3D fluidic capacitors demonstrated that transitioning from planar to non-planar diaphragm architectures improved component performance. Flow rectification experiments for 3D printed fluidic diodes revealed a diodicity of 80.6 ± 1.8. Geometry-based gain enhancement for 3D printed fluidic transistors yielded pressure gain of 3.01 ± 0.78. Consistent with additional additive manufacturing methodologies, the use of digitally-transferrable 3D models of fluidic components combined with commercially-available 3D printers could extend the fluidic routing capabilities presented here to researchers in fields beyond the core engineering community. PMID:26725379

  11. 3D printed microfluidic circuitry via multijet-based additive manufacturing.

    PubMed

    Sochol, R D; Sweet, E; Glick, C C; Venkatesh, S; Avetisyan, A; Ekman, K F; Raulinaitis, A; Tsai, A; Wienkers, A; Korner, K; Hanson, K; Long, A; Hightower, B J; Slatton, G; Burnett, D C; Massey, T L; Iwai, K; Lee, L P; Pister, K S J; Lin, L

    2016-02-21

    The miniaturization of integrated fluidic processors affords extensive benefits for chemical and biological fields, yet traditional, monolithic methods of microfabrication present numerous obstacles for the scaling of fluidic operators. Recently, researchers have investigated the use of additive manufacturing or "three-dimensional (3D) printing" technologies - predominantly stereolithography - as a promising alternative for the construction of submillimeter-scale fluidic components. One challenge, however, is that current stereolithography methods lack the ability to simultaneously print sacrificial support materials, which limits the geometric versatility of such approaches. In this work, we investigate the use of multijet modelling (alternatively, polyjet printing) - a layer-by-layer, multi-material inkjetting process - for 3D printing geometrically complex, yet functionally advantageous fluidic components comprised of both static and dynamic physical elements. We examine a fundamental class of 3D printed microfluidic operators, including fluidic capacitors, fluidic diodes, and fluidic transistors. In addition, we evaluate the potential to advance on-chip automation of integrated fluidic systems via geometric modification of component parameters. Theoretical and experimental results for 3D fluidic capacitors demonstrated that transitioning from planar to non-planar diaphragm architectures improved component performance. Flow rectification experiments for 3D printed fluidic diodes revealed a diodicity of 80.6 ± 1.8. Geometry-based gain enhancement for 3D printed fluidic transistors yielded pressure gain of 3.01 ± 0.78. Consistent with additional additive manufacturing methodologies, the use of digitally-transferrable 3D models of fluidic components combined with commercially-available 3D printers could extend the fluidic routing capabilities presented here to researchers in fields beyond the core engineering community.

  12. Expanding Music Listening Experience through Drawing

    ERIC Educational Resources Information Center

    Han, Yo-Jung

    2016-01-01

    Drawing while listening to music provides an opportunity for students to imagine and associate, leading to holistic listening experience. The personal qualitative listening experience triggered by music can be revealed in their drawings. In the process of representing of the listening experience through drawing, students can also increase their…

  13. Archimedes: Accelerator Reveals Ancient Text

    SciTech Connect

    Bergmann, Uwe

    2004-02-24

    Archimedes (287-212 BC), who is famous for shouting 'Eureka' (I found it) is considered one of the most brilliant thinkers of all times. The 10th-century parchment document known as the 'Archimedes Palimpsest' is the unique source for two of the great Greek's treatises. Some of the writings, hidden under gold forgeries, have recently been revealed at the Stanford Synchrotron Radiation Laboratory at SLAC. An intense x-ray beam produced in a particle accelerator causes the iron in original ink, which has been partly erased and covered, to send out a fluorescence glow. A detector records the signal and a digital image showing the ancient writings is produced. Please join us in this fascinating journey of a 1,000-year-old parchment from its origin in the Mediterranean city of Constantinople to a particle accelerator in Menlo Park.

  14. Revealing Non-Covalent Interactions

    PubMed Central

    Johnson, Erin R.; Keinan, Shahar; Mori-Sánchez, Paula; Contreras-García, Julia; Cohen, Aron J.; Yang, Weitao

    2010-01-01

    Molecular structure does not easily identify the intricate non-covalent interactions that govern many areas of biology and chemistry, including design of new materials and drugs. We develop an approach to detect non-covalent interactions in real space, based on the electron density and its derivatives. Our approach reveals underlying chemistry that compliments the covalent structure. It provides a rich representation of van der Waals interactions, hydrogen bonds, and steric repulsion in small molecules, molecular complexes, and solids. Most importantly, the method, requiring only knowledge of the atomic coordinates, is efficient and applicable to large systems, such as proteins or DNA. Across these applications, a view of non-bonded interactions emerges as continuous surfaces rather than close contacts between atom pairs, offering rich insight into the design of new and improved ligands. PMID:20394428

  15. Revealing hidden genuine tripartite nonlocality

    NASA Astrophysics Data System (ADS)

    Paul, Biswajit; Mukherjee, Kaushiki; Sarkar, Debasis

    2016-11-01

    Nonlocal correlations arising from measurements on tripartite entangled states can be classified into two groups, one genuinely three-way nonlocal and other local with respect to some bipartition. Still, whether a genuinely tripartite entangled quantum state can exhibit genuine three-way nonlocality remains a challenging problem as far as measurement context is concerned. Here we introduce an approach in this regard. We consider three tripartite quantum states, none of which is genuinely three-way nonlocal in a specific Bell scenario (three parties, two measurements per party, two outcomes per measurement), but they can exhibit genuine three-way nonlocality when the initial states are subjected to stochastic local operations and classical communication. So, genuine three-way nonlocality is a resource which can be revealed by using a sequence of measurements.

  16. 49 CFR 1108.12 - Additional matters.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Additional matters. 1108.12 Section 1108.12 Transportation Other Regulations Relating to Transportation (Continued) SURFACE TRANSPORTATION BOARD, DEPARTMENT... JURISDICTION OF THE SURFACE TRANSPORTATION BOARD § 1108.12 Additional matters. Where an arbitration demand...

  17. 49 CFR 1108.12 - Additional matters.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 8 2012-10-01 2012-10-01 false Additional matters. 1108.12 Section 1108.12 Transportation Other Regulations Relating to Transportation (Continued) SURFACE TRANSPORTATION BOARD, DEPARTMENT... JURISDICTION OF THE SURFACE TRANSPORTATION BOARD § 1108.12 Additional matters. Where an arbitration demand...

  18. 49 CFR 1108.12 - Additional matters.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 8 2011-10-01 2011-10-01 false Additional matters. 1108.12 Section 1108.12 Transportation Other Regulations Relating to Transportation (Continued) SURFACE TRANSPORTATION BOARD, DEPARTMENT... JURISDICTION OF THE SURFACE TRANSPORTATION BOARD § 1108.12 Additional matters. Where an arbitration demand...

  19. 15 CFR 990.66 - Additional considerations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Additional considerations. 990.66 Section 990.66 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued... NATURAL RESOURCE DAMAGE ASSESSMENTS Restoration Implementation Phase § 990.66 Additional...

  20. 10 CFR 2.605 - Additional considerations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Additional considerations. 2.605 Section 2.605 Energy NUCLEAR REGULATORY COMMISSION RULES OF PRACTICE FOR DOMESTIC LICENSING PROCEEDINGS AND ISSUANCE OF ORDERS... Permit § 2.605 Additional considerations. (a) The Commission will not conduct more than one review...

  1. 10 CFR 2.625 - Additional considerations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Additional considerations. 2.625 Section 2.625 Energy NUCLEAR REGULATORY COMMISSION RULES OF PRACTICE FOR DOMESTIC LICENSING PROCEEDINGS AND ISSUANCE OF ORDERS... License Under 10 Cfr Part 52 § 2.625 Additional considerations. (a) The Commission will not conduct...

  2. 42 CFR 52d.9 - Additional conditions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Additional conditions. 52d.9 Section 52d.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL CANCER INSTITUTE CLINICAL CANCER EDUCATION PROGRAM § 52d.9 Additional conditions. The Director, NCI, may with respect to...

  3. 42 CFR 52d.9 - Additional conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Additional conditions. 52d.9 Section 52d.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL CANCER INSTITUTE CLINICAL CANCER EDUCATION PROGRAM § 52d.9 Additional conditions. The Director, NCI, may with respect to...

  4. 42 CFR 52d.9 - Additional conditions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Additional conditions. 52d.9 Section 52d.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL CANCER INSTITUTE CLINICAL CANCER EDUCATION PROGRAM § 52d.9 Additional conditions. The Director, NCI, may with respect to...

  5. 42 CFR 52d.9 - Additional conditions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Additional conditions. 52d.9 Section 52d.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL CANCER INSTITUTE CLINICAL CANCER EDUCATION PROGRAM § 52d.9 Additional conditions. The Director, NCI, may with respect to...

  6. 42 CFR 52d.9 - Additional conditions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Additional conditions. 52d.9 Section 52d.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL CANCER INSTITUTE CLINICAL CANCER EDUCATION PROGRAM § 52d.9 Additional conditions. The Director, NCI, may with respect to...

  7. 43 CFR 3154.2 - Additional bonding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Additional bonding. 3154.2 Section 3154.2 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT... Requirements § 3154.2 Additional bonding. The authorized officer may increase the amount of any bond that...

  8. Asthma and anaphylactoid reactions to food additives.

    PubMed Central

    Tarlo, S. M.; Sussman, G. L.

    1993-01-01

    Presumed allergic reactions to hidden food additives are both controversial and important. Clinical manifestations include asthma, urticaria, angioedema, and anaphylactic-anaphylactoid events. Most adverse reactions are caused by just a few additives, such as sulfites and monosodium glutamate. Diagnosis is suspected from the history and confirmed by specific challenge. The treatment is specific avoidance. PMID:8499792

  9. 42 CFR 52e.9 - Additional conditions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Additional conditions. 52e.9 Section 52e.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL HEART, LUNG, AND BLOOD INSTITUTE GRANTS FOR PREVENTION AND CONTROL PROJECTS § 52e.9 Additional conditions. The...

  10. 42 CFR 52e.9 - Additional conditions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Additional conditions. 52e.9 Section 52e.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL HEART, LUNG, AND BLOOD INSTITUTE GRANTS FOR PREVENTION AND CONTROL PROJECTS § 52e.9 Additional conditions. The...

  11. 42 CFR 52e.9 - Additional conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Additional conditions. 52e.9 Section 52e.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL HEART, LUNG, AND BLOOD INSTITUTE GRANTS FOR PREVENTION AND CONTROL PROJECTS § 52e.9 Additional conditions. The...

  12. Fuel compositions containing deposit control additives

    SciTech Connect

    Lilburn, J.E.

    1980-11-18

    Fuel compositions are provided which contain a deposit control additive. The deposit control additive is produced by reacting a hydrocarbylpoly(oxyalkylene) alcohol with excess phosgene and an excess amount of certain polyamines. The product comprises hydrocarbylpoly(oxyalkylene) ureylene carbamates.

  13. 42 CFR 52a.9 - Additional conditions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Additional conditions. 52a.9 Section 52a.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CENTER GRANTS § 52a.9 Additional conditions. The Director may, with respect to any grant...

  14. 42 CFR 52b.13 - Additional conditions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Additional conditions. 52b.13 Section 52b.13 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.13 Additional conditions. The Director may with respect to any...

  15. 42 CFR 52b.13 - Additional conditions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Additional conditions. 52b.13 Section 52b.13 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.13 Additional conditions. The Director may with respect to any...

  16. 42 CFR 52a.9 - Additional conditions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Additional conditions. 52a.9 Section 52a.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CENTER GRANTS § 52a.9 Additional conditions. The Director may, with respect to any grant...

  17. 42 CFR 52a.9 - Additional conditions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Additional conditions. 52a.9 Section 52a.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CENTER GRANTS § 52a.9 Additional conditions. The Director may, with respect to any grant...

  18. 42 CFR 52a.9 - Additional conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Additional conditions. 52a.9 Section 52a.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CENTER GRANTS § 52a.9 Additional conditions. The Director may, with respect to any grant...

  19. 42 CFR 52b.13 - Additional conditions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Additional conditions. 52b.13 Section 52b.13 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.13 Additional conditions. The Director may with respect to any...

  20. 42 CFR 52b.13 - Additional conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Additional conditions. 52b.13 Section 52b.13 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.13 Additional conditions. The Director may with respect to any...