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Sample records for e2f-hdac complexes negatively

  1. A Developmental Study of Factivity and Negation in Complex Syntax.

    ERIC Educational Resources Information Center

    Hopmann, Marita R.; Maratsos, Michael P.

    Two groups of preschoolers and one of young grade-schoolers were tested for their comprehension of presuppositions and negation in complex syntax. Four types of sentences were presented: affirmative and negative versions of sentences with factive main predicates (which presuppose the truth of the proposition of the complement clause) and with…

  2. Negative Ions Enhance Survival of Membrane Protein Complexes

    NASA Astrophysics Data System (ADS)

    Liko, Idlir; Hopper, Jonathan T. S.; Allison, Timothy M.; Benesch, Justin L. P.; Robinson, Carol V.

    2016-06-01

    Membrane protein complexes are commonly introduced to the mass spectrometer solubilized in detergent micelles. The collisional activation used to remove the detergent, however, often causes protein unfolding and dissociation. As in the case for soluble proteins, electrospray in the positive ion mode is most commonly used for the study of membrane proteins. Here we show several distinct advantages of employing the negative ion mode. Negative polarity can yield lower average charge states for membrane proteins solubilized in saccharide detergents, with enhanced peak resolution and reduced adduct formation. Most importantly, we demonstrate that negative ion mode electrospray ionization (ESI) minimizes subunit dissociation in the gas phase, allowing access to biologically relevant oligomeric states. Together, these properties mean that intact membrane protein ions can be generated in a greater range of solubilizing detergents. The formation of negative ions, therefore, greatly expands the possibilities of using mass spectrometry on this intractable class of protein.

  3. Negative Ions Enhance Survival of Membrane Protein Complexes.

    PubMed

    Liko, Idlir; Hopper, Jonathan T S; Allison, Timothy M; Benesch, Justin L P; Robinson, Carol V

    2016-06-01

    Membrane protein complexes are commonly introduced to the mass spectrometer solubilized in detergent micelles. The collisional activation used to remove the detergent, however, often causes protein unfolding and dissociation. As in the case for soluble proteins, electrospray in the positive ion mode is most commonly used for the study of membrane proteins. Here we show several distinct advantages of employing the negative ion mode. Negative polarity can yield lower average charge states for membrane proteins solubilized in saccharide detergents, with enhanced peak resolution and reduced adduct formation. Most importantly, we demonstrate that negative ion mode electrospray ionization (ESI) minimizes subunit dissociation in the gas phase, allowing access to biologically relevant oligomeric states. Together, these properties mean that intact membrane protein ions can be generated in a greater range of solubilizing detergents. The formation of negative ions, therefore, greatly expands the possibilities of using mass spectrometry on this intractable class of protein. Graphical Abstract ᅟ. PMID:27106602

  4. Negative Ions Enhance Survival of Membrane Protein Complexes

    NASA Astrophysics Data System (ADS)

    Liko, Idlir; Hopper, Jonathan T. S.; Allison, Timothy M.; Benesch, Justin L. P.; Robinson, Carol V.

    2016-04-01

    Membrane protein complexes are commonly introduced to the mass spectrometer solubilized in detergent micelles. The collisional activation used to remove the detergent, however, often causes protein unfolding and dissociation. As in the case for soluble proteins, electrospray in the positive ion mode is most commonly used for the study of membrane proteins. Here we show several distinct advantages of employing the negative ion mode. Negative polarity can yield lower average charge states for membrane proteins solubilized in saccharide detergents, with enhanced peak resolution and reduced adduct formation. Most importantly, we demonstrate that negative ion mode electrospray ionization (ESI) minimizes subunit dissociation in the gas phase, allowing access to biologically relevant oligomeric states. Together, these properties mean that intact membrane protein ions can be generated in a greater range of solubilizing detergents. The formation of negative ions, therefore, greatly expands the possibilities of using mass spectrometry on this intractable class of protein.

  5. [Application of therapy in negative pressure complex wounds in pediatrics].

    PubMed

    Fernández Sánchez, Rosario; Muñoz-Miguelsanz, María Ángeles

    2016-01-01

    Negative pressure wound therapy (NPWT) has been widely used in the adult patient, contrary to what happens in children, with just a few long series papers. NPWT avoids long and expensive hospital admissions, reducing the hospital costs; it also decreases the family dynamics and allows for an early return to everyday activities. In this article, we present three clinical cases consisting of a toddler, a child and a teenager with complex wounds treated with NPWT in the pediatric surgery department of the Virgen de las Nieves University Hospital in Granada. The results were excellent, with a good adherence to treatment in all cases, achieving a complete closure in two cases; the third case needed a deferred surgical closure after surgical site preparation, and showed a decrease of the wound size after the NPWT. Moreover, successful pain management was achieved during the wound cleansing, which was done under an ambulatory regime. No general anesthesia was needed. From our experience, we propose the NPWT as an alternative therapy to the classic surgical approach for this type of complex lesions in children, which offers the same advantages and results than in adults. PMID:27297175

  6. Complex Teacher Evaluation Systems Can Produce Negative Perceptions

    ERIC Educational Resources Information Center

    Schumacher, Gary

    2010-01-01

    The purpose of this study was to determine teacher perceptions of the impact on instructional practice when using a complex, standards-based performance evaluation system. The study used expectancy theory to investigate teacher expectancy (did they believe they could enhance their practice to the identified program standards?), instrumentality…

  7. Negative refraction of complex lattices of dielectric cylinders

    NASA Astrophysics Data System (ADS)

    Jin, Yi; He, Sailing

    2007-01-01

    Some photonic crystals (PCs) consisting of complex lattices of dielectric cylinders can have an effective refraction index (n) of -1. Subwavelength imaging by a slab of a honeycomb PC of dielectric cylinders with n=-1 is investigated and an open resonator with a quality factor higher than 3000 is designed with the same PC. Air PC interfaces with low reflection are also used for the slab lens and open resonator.

  8. Route complexity and simulated physical ageing negatively influence wayfinding.

    PubMed

    Zijlstra, Emma; Hagedoorn, Mariët; Krijnen, Wim P; van der Schans, Cees P; Mobach, Mark P

    2016-09-01

    The aim of this age-simulation field experiment was to assess the influence of route complexity and physical ageing on wayfinding. Seventy-five people (aged 18-28) performed a total of 108 wayfinding tasks (i.e., 42 participants performed two wayfinding tasks and 33 performed one wayfinding task), of which 59 tasks were performed wearing gerontologic ageing suits. Outcome variables were wayfinding performance (i.e., efficiency and walking speed) and physiological outcomes (i.e., heart and respiratory rates). Analysis of covariance showed that persons on more complex routes (i.e., more floor and building changes) walked less efficiently than persons on less complex routes. In addition, simulated elderly participants perform worse in wayfinding than young participants in terms of speed (p < 0.001). Moreover, a linear mixed model showed that simulated elderly persons had higher heart rates and respiratory rates compared to young people during a wayfinding task, suggesting that simulated elderly consumed more energy during this task. PMID:27184311

  9. Visualizing Proteins and Macromolecular Complexes by Negative Stain EM: from Grid Preparation to Image Acquisition

    PubMed Central

    Booth, David S.; Avila-Sakar, Agustin; Cheng, Yifan

    2011-01-01

    Single particle electron microscopy (EM), of both negative stained or frozen hydrated biological samples, has become a versatile tool in structural biology 1. In recent years, this method has achieved great success in studying structures of proteins and macromolecular complexes 2, 3. Compared with electron cryomicroscopy (cryoEM), in which frozen hydrated protein samples are embedded in a thin layer of vitreous ice 4, negative staining is a simpler sample preparation method in which protein samples are embedded in a thin layer of dried heavy metal salt to increase specimen contrast 5. The enhanced contrast of negative stain EM allows examination of relatively small biological samples. In addition to determining three-dimensional (3D) structure of purified proteins or protein complexes 6, this method can be used for much broader purposes. For example, negative stain EM can be easily used to visualize purified protein samples, obtaining information such as homogeneity/heterogeneity of the sample, formation of protein complexes or large assemblies, or simply to evaluate the quality of a protein preparation. In this video article, we present a complete protocol for using an EM to observe negatively stained protein sample, from preparing carbon coated grids for negative stain EM to acquiring images of negatively stained sample in an electron microscope operated at 120kV accelerating voltage. These protocols have been used in our laboratory routinely and can be easily followed by novice users. PMID:22215030

  10. Negative cortical DC shifts preceding and accompanying simple and complex sequential movements.

    PubMed

    Lang, W; Zilch, O; Koska, C; Lindinger, G; Deecke, L

    1989-01-01

    Negative cortical DC shifts preceding and accompanying the execution of four different motor tasks were analysed in 18 subjects (Ss): Repetitive flexions and extensions of the forefinger had to be performed either by the right (1) or the left (2) hand. This simple motor task was compared to a complex one in which flexions and extensions of forefinger and hand had to be alternated in a fixed sequence. The complex task had either to be performed by the right (3) or the left (4) hand. Thus, the four conditions differed in the side of the performing hand (right/left) and in task-complexity (simple/complex). After its voluntary initiation, each task had to be performed for at least a period of six seconds. A Bereitschaftspotential (BP) preceded the voluntary initiation of the movement. Task-performance was accompanied by a negative DC shift called a performance-related negativity (N-P). Amplitudes of BP and N-P were compared by analysis of variance (ANOVA) using the factors "performing hand" (right/left) and "task-complexity" (simple/complex). "Performing hand" had significant effects on N-BP and N-P in C3* and C4* (positioned over the primary motor cortex) but did not influence mid-central (Cz*), frontal (F3, Fz, and F4) or parietal (P3, Pz, P4) recordings. "Task-complexity" had significant effects on N-P in mid-central (Cz*, C1*, C2*) and parietal (P3, Pz) recordings with higher negativity for complex movements. Recordings in C3* and C4* did not vary with "task complexity".(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2924844

  11. Prediction of Negative Attitude from Congruity, Summation, and Logarithm Formulae for the Evaluation of Complex Stimuli

    ERIC Educational Resources Information Center

    Anderson, Lynn R.

    1970-01-01

    The purpose of the study was to Compare the efficacy of an averaging (congruity) formula vs. an additive formula for the evaluation of complex stimuli when negative adjectives were used to describe the attitude topic. A logarithm formula proposed by Mannis, Gleason, and Dawes was also used. (DB)

  12. Stealth fast photoswitching of negative photochromic naphthalene-bridged phenoxyl-imidazolyl radical complexes.

    PubMed

    Mutoh, Katsuya; Kobayashi, Yoichi; Hirao, Yasukazu; Kubo, Takashi; Abe, Jiro

    2016-05-21

    Naphthalene-bridged phenoxyl-imidazolyl radical complex (Np-PIC) is a novel fast switchable negative photochromic compound, which shows the thermal back reaction in the millisecond time scale. Upon UV light irradiation, Np-PIC shows the hypochromic effect in the UVA region due to there being less conjugation in the transient isomer. By replacing the phenoxyl unit with a naphthoxyl unit, the molecular structure has an asymmetric carbon, leading to fast chiroptical switching. This simple molecular design will be a good candidate for the future development of negative photochromic compounds. PMID:27124495

  13. Natural media with negative index of refraction: Perspectives of complex transition metal oxides (Review Article)

    NASA Astrophysics Data System (ADS)

    Fertman, E. L.; Beznosov, A. B.

    2011-07-01

    The capabilities of perovskite-like compounds with the effect of colossal magnetoresistance (CMR) and some other complex oxides to have a negative index of refraction (NIR) are considered. Physical properties of these compounds are also analyzed from the standpoint of designing tunable metamaterials on their base. Of particular interest are temperature and magnetic field driven first-order transformations in oxides with perovskite structure and in spinels. These transformations give rise to nanophase separated states, using which the properties of negative refraction can be affected. The magnetic-field controlled metamaterials with CMR oxides as a boundary NIR media for a photonic crystal are discussed.

  14. Fast Negative Photochromism of 1,1'-Binaphthyl-Bridged Phenoxyl-Imidazolyl Radical Complex.

    PubMed

    Yamaguchi, Tetsuo; Kobayashi, Yoichi; Abe, Jiro

    2016-01-27

    Negative photochromism, in which a thermally stable colored form isomerizes to the transient colorless form by light irradiation and the back reaction occurs thermally, is advantageous in its applications for photoswitching materials because visible light can cause the photochromic color change of the materials. Moreover, the photochromic color change can be induced even on the inside of the materials due to the absence of the reabsorption of the visible excitation light by the photogenerated colorless species. While several negative photochromic compounds have been reported, the time scales of the back reaction are still slower than minutes, and no available fast responsive negative photochromic compounds have been reported. Here, we developed a negative photochromic 1,1'-binaphthyl-bridged phenoxyl-imidazolyl radical complex (BN-PIC) which enables fast photoswitching by visible light. The stable colored BN-PIC shows instantaneous decoloration by visible light irradiation, and the photogenerated colorless form thermally reverts to the initial colored form with a half-life of 1.9 s at room temperature. BN-PIC can also cause the drastic change in the chiroptical properties by the photochromic reaction, and the rate of the thermal back reaction is affected by the chirality of the solvent. Since the negative photochromic reaction can occur on the inside of the materials, the fast negative photochromism is expected to have an impact in the fields of photoresponsive materials of solid states and molecular aggregates. PMID:26714023

  15. Efficient in vivo gene delivery by the negatively charged complexes of cationic liposomes and plasmid DNA.

    PubMed

    Son, K K; Tkach, D; Hall, K J

    2000-09-29

    We examined changes in zeta potential (the surface charge density, zeta) of the complexes of liposome (nmol)/DNA (microg) (L/D) formed in water at three different ratios (L/D=1, 10 and 20) by changing the ionic strength or pH to find an optimum formulation for in vivo gene delivery. At high DNA concentrations, zeta of the complexes formed in water at L/D=10 was significantly lowered by adding NaCl (zeta=+8.44+/-3.1 to -27.6+/-3.5 mV) or increasing pH from 5 (zeta=+15.3+/-1.0) to 9 (zeta=-22.5+/-2.5 mV). However, the positively charged complexes formed at L/D=20 (zeta=+6.2+/-3.5 mV) became negative as NaCl was added at alkaline pH as observed in medium (zeta=-19.7+/-9.9 mV). Thus, the complexes formed in water under the optimum condition were stable and largely negatively charged at L/D=1 (zeta=-58.1+/-3.9 mV), unstable and slightly positively charged at L/D=10 (zeta=+8.44+/-3.7 mV), and unstable and largely positively charged at L/D=20 (zeta=+24.3+/-3.6 mV). The negatively charged complexes efficiently delivered DNA into both solid and ascitic tumor cells. However, the positively charged complexes were very poor in delivering DNA into solid tumors, yet were efficient in delivering DNA into ascitic tumors grown in the peritoneum regardless of complex size. This slightly lower gene transfer efficiency of the negatively charged complexes can be as efficient as the positively charged ones when an injection is repeated (at least two injections), which is the most common case for therapy regimes. The results indicate that optimum in vivo lipofection may depend on the site of tumor growth. PMID:11018645

  16. Tetramethylammonium hydroxide as a reagent for complex mixture analysis by negative ion electrospray ionization mass spectrometry.

    PubMed

    Lobodin, Vladislav V; Juyal, Priyanka; McKenna, Amy M; Rodgers, Ryan P; Marshall, Alan G

    2013-08-20

    Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) enables the direct characterization of complex mixtures without prior fractionation. High mass resolution can distinguish peaks separated by as little as 1.1 mDa), and high mass accuracy enables assignment of elemental compositions in mixtures that contain tens of thousands of individual components (crude oil). Negative electrospray ionization (ESI) is particularly useful for the speciation of the most acidic petroleum components that are implicated in oil production and processing problems. Here, we replace conventional ammonium hydroxide by tetramethylammonium hydroxide (TMAH, a much stronger base, with higher solubility in toluene) to more uniformly deprotonate acidic components of complex mixtures by negative ESI FTICR MS. The detailed compositional analysis of four crude oils (light to heavy, from different geographical locations) reveals that TMAH reagent accesses 1.5-6 times as many elemental compositions, spanning a much wider range of chemical classes than does NH4OH. For example, TMAH reagent produces abundant negative electrosprayed ions from less acidic and neutral species that are in low abundance or absent with NH4OH reagent. More importantly, the increased compositional coverage of TMAH-modified solvent systems maintains, or even surpasses, the compositional information for the most acidic species. The method is not limited to petroleum-derived materials and could be applied to the analysis of dissolved organic matter, coal, lipids, and other naturally occurring compositionally complex organic mixtures. PMID:23919350

  17. Self-Structures, Negative Events, and Adolescent Depression: Clarifying the Role of Self-Complexity in a Prospective, Multiwave Study

    ERIC Educational Resources Information Center

    Cohen, Joseph R.; Spiegler, Kevin M.; Young, Jami F.; Hankin, Benjamin L.; Abela, John R. Z.

    2014-01-01

    The purpose of this multiwave longitudinal study was to examine the structure of self-complexity and its relation to depressive symptoms in 276 adolescents (M = 12.55; SD = 1.04). Self-complexity, depressive symptoms, and negative events were assessed during a laboratory assessment at baseline, and then depressive symptoms and negative events were…

  18. RUNX3 is a novel negative regulator of oncogenic TEAD-YAP complex in gastric cancer.

    PubMed

    Qiao, Y; Lin, S J; Chen, Y; Voon, D C-C; Zhu, F; Chuang, L S H; Wang, T; Tan, P; Lee, S C; Yeoh, K G; Sudol, M; Ito, Y

    2016-05-19

    Runt-related transcription factor 3 (RUNX3) is a well-documented tumour suppressor that is frequently inactivated in gastric cancer. Here, we define a novel mechanism by which RUNX3 exerts its tumour suppressor activity involving the TEAD-YAP complex, a potent positive regulator of proliferative genes. We report that the TEAD-YAP complex is not only frequently hyperactivated in liver and breast cancer, but also confers a strong oncogenic activity in gastric epithelial cells. The increased expression of TEAD-YAP in tumour tissues significantly correlates with poorer overall survival of gastric cancer patients. Strikingly, RUNX3 physically interacts with the N-terminal region of TEAD through its Runt domain. This interaction markedly reduces the DNA-binding ability of TEAD that attenuates the downstream signalling of TEAD-YAP complex. Mutation of RUNX3 at Arginine 122 to Cysteine, which was previously identified in gastric cancer, impairs the interaction between RUNX3 and TEAD. Our data reveal that RUNX3 acts as a tumour suppressor by negatively regulating the TEAD-YAP oncogenic complex in gastric carcinogenesis. PMID:26364597

  19. Neurophysiological evidence for whole form retrieval of complex derived words: a mismatch negativity study

    PubMed Central

    Hanna, Jeff; Pulvermüller, Friedemann

    2014-01-01

    Complex words can be seen as combinations of elementary units, decomposable into stems and affixes according to morphological rules. Alternatively, complex forms may be stored as single lexical entries and accessed as whole forms. This study uses an event-related potential brain response capable of indexing both whole-form retrieval and combinatorial processing, the Mismatch Negativity (MMN), to investigate early brain activity elicited by morphologically complex derived words in German. We presented complex words consisting of stems “sicher” (secure), or “sauber” (clean) combined with abstract nominalizing derivational affixes -heit or -keit, to form either congruent derived words: “Sicherheit” (security) and “Sauberkeit” (cleanliness), or incongruent derived pseudowords: *“Sicherkeit”, and *“Sauberheit”. Using this orthogonal design, it was possible to record brain responses for -heit and -keit in both congruent and incongruent contexts, therefore balancing acoustic variance. Previous research has shown that incongruent combinations of symbols elicit a stronger MMN than congruent combinations, but that single words or constructions stored as whole forms elicit a stronger MMN than pseudowords or non-existent constructions. We found that congruent derived words elicited a stronger MMN than incongruent derived words, beginning about 150 ms after perception of the critical morpheme. This pattern of results is consistent with whole-form storage of morphologically complex derived words as lexical units, or mini-constructions. Using distributed source localization methods, the MMN enhancement for well-formed derivationally complex words appeared to be most prominent in the left inferior anterior-temporal, bilateral superior parietal and bilateral post-central, supra-marginal areas. In addition, neurophysiological results reflected the frequency of derived forms, thus providing further converging evidence for whole form storage and against a

  20. Basal core promoters control the equilibrium between negative cofactor 2 and preinitiation complexes in human cells

    PubMed Central

    2010-01-01

    Background The general transcription factor TFIIB and its antagonist negative cofactor 2 (NC2) are hallmarks of RNA polymerase II (RNAPII) transcription. Both factors bind TATA box-binding protein (TBP) at promoters in a mutually exclusive manner. Dissociation of NC2 is thought to be followed by TFIIB association and subsequent preinitiation complex formation. TFIIB dissociates upon RNAPII promoter clearance, thereby providing a specific measure for steady-state preinitiation complex levels. As yet, genome-scale promoter mapping of human TFIIB has not been reported. It thus remains elusive how human core promoters contribute to preinitiation complex formation in vivo. Results We compare target genes of TFIIB and NC2 in human B cells and analyze associated core promoter architectures. TFIIB occupancy is positively correlated with gene expression, with the vast majority of promoters being GC-rich and lacking defined core promoter elements. TATA elements, but not the previously in vitro defined TFIIB recognition elements, are enriched in some 4 to 5% of the genes. NC2 binds to a highly related target gene set. Nonetheless, subpopulations show strong variations in factor ratios: whereas high TFIIB/NC2 ratios select for promoters with focused start sites and conserved core elements, high NC2/TFIIB ratios correlate to multiple start-site promoters lacking defined core elements. Conclusions TFIIB and NC2 are global players that occupy active genes. Preinitiation complex formation is independent of core elements at the majority of genes. TATA and TATA-like elements dictate TFIIB occupancy at a subset of genes. Biochemical data support a model in which preinitiation complex but not TBP-NC2 complex formation is regulated. PMID:20230619

  1. Large and negative magnetic anisotropy in pentacoordinate mononuclear Ni(ii) Schiff base complexes.

    PubMed

    Nemec, Ivan; Herchel, Radovan; Svoboda, Ingrid; Boča, Roman; Trávníček, Zdeněk

    2015-05-28

    A series of pentacoordinate Ni(ii) complexes of the general formula [Ni(L5)] () with various pentadentate Schiff base ligands H2L5 (originating in a condensation of aromatic ortho-hydroxy-aldehydes and aliphatic triamines) was synthesized and characterized by X-ray structure analysis and magnetometry. The alternations of substituents on the H2L parent ligand resulted in the complexes with the geometry varying between the square-pyramid and trigonal-bipyramid. In the compounds whose chromophore geometry is closer to a trigonal-bipyramid, a large and negative uniaxial anisotropy (D = -64 cm(-1)) was identified. Moreover, the simple linear expression for the axial zero-field splitting (ZFS) parameter, D/cm(-1) = 32.7(4.8) - 151(10)τ, was proposed, where τ (in degrees) stands for the Addison parameter. The results of magnetic analysis were also supported by ab initio CASSCF/NEVPT2 calculations of the ZFS splitting parameters D and E, and g tensors. Despite large and negative D-values of the reported compounds, slow relaxation of magnetization was not observed either in zero or non-zero static magnetic field, thus no single-molecule magnetic behaviour was detected. PMID:25919125

  2. Complex Negative Regulation of TLR9 by Multiple Proteolytic Cleavage Events.

    PubMed

    Sinha, Siddhartha S; Cameron, Jody; Brooks, James C; Leifer, Cynthia A

    2016-08-15

    TLR9 is an innate immune receptor important for recognizing DNA of host and foreign origin. A mechanism proposed to prevent excessive response to host DNA is the requirement for proteolytic cleavage of TLR9 in endosomes to generate a mature form of the receptor (TLR9(471-1032)). We previously described another cleavage event in the juxtamembrane region of the ectodomain that generated a dominant-negative form of TLR9. Thus, there are at least two independent cleavage events that regulate TLR9. In this study, we investigated whether an N-terminal fragment of TLR9 could be responsible for regulation of the mature or negative-regulatory form. We show that TLR9(471-1032), corresponding to the proteolytically cleaved form, does not function on its own. Furthermore, activity is not rescued by coexpression of the N-terminal fragment (TLR9(1-440)), inclusion of the hinge region (TLR9(441-1032)), or overexpression of UNC93B1, the last of which is critical for trafficking and cleavage of TLR9. TLR9(1-440) coimmunoprecipitates with full-length TLR9 and TLR9(471-1032) but does not rescue the native glycosylation pattern; thus, inappropriate trafficking likely explains why TLR9(471-1032) is nonfunctional. Lastly, we show that TLR9(471-1032) is also a dominant-negative regulator of TLR9 signaling. Together, these data provide a new perspective on the complexity of TLR9 regulation by proteolytic cleavage and offer potential ways to inhibit activity through this receptor, which may dampen autoimmune inflammation. PMID:27421483

  3. Macrophage cell lines derived from major histocompatibility complex II-negative mice

    NASA Technical Reports Server (NTRS)

    Beharka, A. A.; Armstrong, J. W.; Chapes, S. K.; Spooner, B. S. (Principal Investigator)

    1998-01-01

    Two bone-marrow-derived macrophage cell lines, C2D and C2Dt, were isolated from major histocompatibility class II negative knock-out mice. The C2D cell line was stabilized by continuous culture in colony-stimulating factor-1 and the C2Dt cell line was transformed with SV40 virus large T antigen. These cells exhibited phenotypic properties of macrophages including morphology and expression of Mac 1 and Mac 2 cell surface molecules. These cells also had comparable growth to the bone-marrow-derived macrophage cell line B6MP102. These new cell lines were not spontaneously cytotoxic and were only capable of modest killing of F5b tumor cells when stimulated with LPS and interferon-gamma, but not when stimulated with LPS alone or with staphylococcal exotoxin. C2D and C2Dt cells phagocytosed labeled Staphylococcus aureus similarly to B6MP102 cells but less well than C2D peritoneal macrophages. These cell lines secreted interleukin-6, but not tumor necrosis factor or nitric oxide in response to LPS or staphlococcal enterotoxins A or B C2D(t) cells were tumorigenic in C2D and C57BL/6J mice but C2D cells were not. These data suggest that macrophage cell lines can be established from bone marrow cells of major histocompatibility complex II-negative mice.

  4. Parallel calculations of vibrational properties in complex materials: negative thermal expansion and elastic inhomogeneity

    NASA Astrophysics Data System (ADS)

    Vila, F. D.; Rehr, J. J.

    Effects of thermal vibrations are essential to obtain a more complete understanding of the properties of complex materials. For example, they are important in the analysis and simulation of x-ray absorption spectra (XAS). In previous work we introduced an ab initio approach for a variety of vibrational effects, such as crystallographic and XAS Debye-Waller factors, Debye and Einstein temperatures, and thermal expansion coefficients. This approach uses theoretical dynamical matrices from which the locally-projected vibrational densities of states are obtained using a Lanczos recursion algorithm. In this talk I present recent improvements to our implementation, which permit simulations of more complex materials with up to two orders of magnitude larger simulation cells. The method takes advantage of parallelization in calculations of the dynamical matrix with VASP. To illustrate these capabilities we discuss two problems of considerable interest: negative thermal expansion in ZrW2O8; and local inhomogeneities in the elastic properties of supported metal nanoparticles. Both cases highlight the importance of a local treatment of vibrational properties. Supported by DOE Grant DE-FG02-03ER15476, with computer support from DOE-NERSC.

  5. Targeting triple negative breast cancer cells by N3-substituted 9,10-Phenanthrenequinone thiosemicarbazones and their metal complexes

    NASA Astrophysics Data System (ADS)

    Afrasiabi, Zahra; Stovall, Preston; Finley, Kristen; Choudhury, Amitava; Barnes, Charles; Ahmad, Aamir; Sarkar, Fazlul; Vyas, Alok; Padhye, Subhash

    2013-10-01

    Novel N3-substituted 9,10-Phenanthrenequinone thiosemicarbazones and their copper, nickel and palladium complexes are structurally characterized and reported along with the single crystal X-ray structures of three ligands and one nickel complex. All compounds were evaluated for their antiproliferative potential against Triple Negative Breast Cancer (TNBC) cells which have poor prognosis and no effective drugs to treat with. All compounds exhibited antiproliferative activity against these cells. Among the metal complexes evaluated, redox active copper complexes were found to be more potent. The possible mechanism for such enhanced activity can be attributed to the generation of oxidative stress, which was amenable for targeting through metal complexation.

  6. Use of Closed Incision Management with Negative Pressure Therapy for Complex Cardiac Patients

    PubMed Central

    2016-01-01

    Background: In patients with major comorbidities undergoing complex cardiothoracic surgery, incision management is critical. This retrospective review evaluated negative pressure over closed sternal incisions in cardiac patients with multiple comorbidities within 30 days post-median sternotomy. Methods: Records of post-sternotomy patients treated with Prevena™ Incision Management System (KCI, an Acelity company, San Antonio, TX), a closed incision negative pressure therapy (ciNPT), were reviewed from September 2010 through September 2014. Data collected included demographics, major comorbidities, types of surgery, relevant medical history, incision length, therapy duration, time to follow-up, and incision complications. Descriptive statistics were computed for continuous variables, frequency, and percentages for categorical variables. Results: Twenty-seven patients were treated with ciNPT between September 2010 and September 2014. The mean patient age was 62.5 (SD 7.9), and the mean body mass index (BMI) was 38.5 (SD 4.4) kg/m2. Risk factors included obesity (BMI ≥ 30 kg/m2, 27/27; 100%), diabetes (25/27; 92.6%), hypertension (16/27; 59.3%), and 20/27 patients (74%) had ≥ 5 comorbidities. Mean ciNPT duration was 5.6 (SD 0.9) days. Within 30 days post-surgery, 21/27 (77.8%) patients had intact incisions with good reapproximation. Two patients experienced minor dehiscences; four cases of superficial cellulitis were treated and resolved. One patient with a dehiscence was readmitted for intravenous antibiotics and five patients were managed successfully with antibiotics as outpatients. All patients had intact incisions with good skin approximation at final follow-up. Conclusions: In this retrospective study of post-sternotomy patients at high risk of developing complications, ciNPT over closed sternal incisions resulted in favorable outcomes within 30 days of surgery. PMID:27026831

  7. Positive and negative ion mode ESI-MS and MS/MS for studying drug-DNA complexes

    NASA Astrophysics Data System (ADS)

    Rosu, Frédéric; Pirotte, Sophie; Pauw, Edwin De; Gabelica, Valérie

    2006-07-01

    We report systematic investigation of duplex DNA complexes with minor groove binders (Hoechsts 33258 and 33342, netropsin and DAPI) and intercalators (daunomycin, doxorubicin, actinomycin D, ethidium, cryptolepine, neocryptolepine, m-Amsacrine, proflavine, ellipticine and mitoxantrone) by ESI-MS and ESI-MS/MS in the negative ion mode and in the positive ion mode. The apparent solution phase equilibrium binding constants can be determined by measuring relative intensities in the ESI-MS spectrum. While negative ion mode gives reliable results, positive ion mode gives a systematic underestimation of the binding constants and even a complete suppression of the complexes for intercalators lacking functional groups capable of interacting in the grooves. In the second part of the paper we systematically compare MS/MS fragmentation channels and breakdown curves in the positive and the negative modes, and discuss the possible uses and caveats of MS/MS in drug-DNA complexes. In the negative mode, the drugs can be separated in three groups: (1) those that leave the complex with no net charge; (2) those that leave the complex with a negative charge; and (3) those that remain attached on the strands upon dissociation of the duplex due to their positive charge. In the positive ion mode, all complexes fragment via the loss of protonated drug. Information on the stabilization of the complex by drug-DNA noncovalent interactions can be obtained straightforwardly only in the case of neutral drug loss. In all other cases, proton affinity (in the positive ion mode), gas-phase basicity (in the negative ion mode) and coulombic repulsion are the major factors influencing the fragmentation channel and the dissociation kinetics.

  8. Negative membrane curvature catalyzes nucleation of endosomal sorting complex required for transport (ESCRT)-III assembly.

    PubMed

    Lee, Il-Hyung; Kai, Hiroyuki; Carlson, Lars-Anders; Groves, Jay T; Hurley, James H

    2015-12-29

    The endosomal sorting complexes required for transport (ESCRT) machinery functions in HIV-1 budding, cytokinesis, multivesicular body biogenesis, and other pathways, in the course of which it interacts with concave membrane necks and bud rims. To test the role of membrane shape in regulating ESCRT assembly, we nanofabricated templates for invaginated supported lipid bilayers. The assembly of the core ESCRT-III subunit CHMP4B/Snf7 is preferentially nucleated in the resulting 100-nm-deep membrane concavities. ESCRT-II and CHMP6 accelerate CHMP4B assembly by increasing the concentration of nucleation seeds. Superresolution imaging was used to visualize CHMP4B/Snf7 concentration in a negatively curved annulus at the rim of the invagination. Although Snf7 assemblies nucleate slowly on flat membranes, outward growth onto the flat membrane is efficiently nucleated at invaginations. The nucleation behavior provides a biophysical explanation for the timing of ESCRT-III recruitment and membrane scission in HIV-1 budding. PMID:26668364

  9. Bound Na(+) is a Negative Effecter for Thrombin-Substrate Stereospecific Complex Formation.

    PubMed

    Kurisaki, Ikuo; Takayanagi, Masayoshi; Nagaoka, Masataka

    2016-05-26

    Thrombin has been studied as a paradigmatic protein of Na(+)-activated allosteric enzymes. Earlier structural studies suggest that Na(+)-binding promotes the thrombin-substrate association reaction. However, it is still elusive because (1) the structural change, driven by Na(+)-binding, is as small as the thermal fluctuation, and (2) the bound Na(+) is close to Asp189 in the primary substrate binding pocket (S1-pocket), possibly preventing substrate access via repulsive interaction. It still remains a matter of debate whether Na(+)-binding actually promotes the reaction. To solve this problem, we examined the effect of Na(+) on the reaction by employing molecular dynamics (MD) simulations. By executing independent 210 MD simulations of apo and holo systems, we obtained 80 and 26 trajectories undergoing substrate access to S1-pocket, respectively. Interestingly, Na(+)-binding results in a 3-fold reduction of the substrate access. Furthermore, we examined works for the substrate access and release, and found that Na(+)-binding is disadvantageous for the presence of the substrate in the S1-pocket. These observations provide the insight that the bound Na(+) is essentially a negative effecter in thrombin-substrate stereospecific complex formation. The insight rationalizes an enigmatic feature of thrombin, relatively low Na(+)-binding affinity. This is essential to reduce the disadvantage of Na(+)-binding in the substrate-binding. PMID:27164318

  10. Characterization to species level of Mycobacterium avium complex strains from human immunodeficiency virus-positive and -negative patients.

    PubMed Central

    Kyriakopoulos, A M; Tassios, P T; Matsiota-Bernard, P; Marinis, E; Tsaousidou, S; Legakis, N J

    1997-01-01

    Forty human clinical Mycobacterium avium-M. intracellulare complex strains isolated in Greece were characterized to the species level by PCR with three sets of primers specific for one or both species. M. avium predominated in both human immunodeficiency virus-positive and -negative patients, but the frequency of M. intracellulare isolation appeared to be higher in the latter. PMID:9350780

  11. Catalytic Water Oxidation by Ruthenium Complexes Containing Negatively Charged Ligand Frameworks.

    PubMed

    Kärkäs, Markus D; Åkermark, Björn

    2016-04-01

    Artificial photosynthesis represents an attractive way of converting solar energy into storable chemical energy. The H2O oxidation half-reaction, which is essential for producing the necessary reduction equivalents, is an energy-demanding transformation associated with a high kinetic barrier. Herein we present a couple of efficient Ru-based catalysts capable of mediating this four-proton-four-electron oxidation. We have focused on the incorporation of negatively charged ligands, such as carboxylate, phenol, and imidazole, into the catalysts to decrease the redox potentials. This account describes our work in designing Ru catalysts based on this idea. The presence of the negatively charged ligands is crucial for stabilizing the metal centers, allowing for light-driven H2O oxidation. Mechanistic details associated with the designed catalysts are also presented. PMID:26991306

  12. Does job complexity mitigate the negative effect of emotion-rule dissonance on employee burnout?

    PubMed Central

    Kubicek, Bettina; Korunka, Christian

    2015-01-01

    ABSTRACT In interactions with clients or patients, human service workers are at risk of experiencing discrepancies between felt and organizationally mandated emotions (i.e. emotion-rule dissonance). Given the documented detrimental effects of such discrepancies on employee strain, the present study investigated whether job complexity mitigates the relation between emotion-rule dissonance and employee burnout using data from a two-wave panel study of eldercare workers (N = 583, 16-month time lag). Structural equation modelling revealed that emotion-rule dissonance at Time 1 preceded emotional exhaustion and depersonalization at Time 2. Beyond that, employees whose work offered job complexity were found to suffer less from emotional exhaustion and depersonalization when encountering discrepancies between felt and stipulated emotions compared to employees who conducted noncomplex work. Thus, designing complex tasks appears to be a crucial starting point for alleviating employee burnout in jobs that provoke emotion-rule dissonance. PMID:26681818

  13. Negative results in phase III trials of complex interventions: cause for concern or just good science?

    PubMed

    Crawford, Mike J; Barnicot, Kirsten; Patterson, Sue; Gold, Christian

    2016-07-01

    Not all interventions that show promise in exploratory trials will be supported in phase III studies. But the high failure rate in recent trials of complex mental health interventions is a concern. Proper consideration of trial processes and greater use of adaptive trial designs could ensure better use of available resources. PMID:27369475

  14. Pavement crack detection combining non-negative feature with fast LoG in complex scene

    NASA Astrophysics Data System (ADS)

    Wang, Wanli; Zhang, Xiuhua; Hong, Hanyu

    2015-12-01

    Pavement crack detection is affected by much interference in the realistic situation, such as the shadow, road sign, oil stain, salt and pepper noise etc. Due to these unfavorable factors, the exist crack detection methods are difficult to distinguish the crack from background correctly. How to extract crack information effectively is the key problem to the road crack detection system. To solve this problem, a novel method for pavement crack detection based on combining non-negative feature with fast LoG is proposed. The two key novelties and benefits of this new approach are that 1) using image pixel gray value compensation to acquisit uniform image, and 2) combining non-negative feature with fast LoG to extract crack information. The image preprocessing results demonstrate that the method is indeed able to homogenize the crack image with more accurately compared to existing methods. A large number of experimental results demonstrate the proposed approach can detect the crack regions more correctly compared with traditional methods.

  15. Properties of clusters in the gas phase. V - Complexes of neutral molecules onto negative ions

    NASA Technical Reports Server (NTRS)

    Keesee, R. G.; Lee, N.; Castleman, A. W., Jr.

    1980-01-01

    Ion-molecules association reactions of the form A(-)(B)n-1 + B = A(-)(B)n were studied over a range of temperatures in the gas phase using high pressure mass spectrometry. Enthalpy and entropy changes were determined for the stepwise clustering reactions of (1) sulfur dioxide onto Cl(-), I(-), and NO2(-) with n ranging from one to three or four, and onto SO2(-) and SO3(-) with n equal to one; and (2) carbon dioxide onto Cl(-), I(-), NO2(-), CO3(-), and SO3(-) with n equal to one. From these data and earlier hydration results, the order of the magnitude of the enthalpy changes on the association of the first neutral for a series of negative ions was found to parallel the gas-phase basicity of those anions.

  16. Changes of slow cortical negative DC-potentials during the acquisition of a complex finger motor task.

    PubMed

    Niemann, J; Winker, T; Gerling, J; Landwehrmeyer, B; Jung, R

    1991-01-01

    To study whether electrophysiological correlates of increasing motor skill can be demonstrated in man, we recorded cortical negative DC-potentials during the acquisition of a complex finger movement in 21 subjects. The movement consisted in moving a matchstick to and fro between the index finger (II) and the little finger (V). Cortical negative DC-potentials were recorded at Fz, Cz, C1, C2 and Pz. As a control a simple finger movement was performed during the same session by 7 of the Ss. Both tasks were repeated 60-80 times and averages of the first and the last 15 artifact-free single runs were compared. Whereas only a slight, inconstant decrease in surface electronegativity during the simple motor task was observed, a significant reduction in potential size occurred during the complex task at Cz (maximum), C1, C2 and Pz but not at Fz. In addition, a significant difference in the decrease of surface electronegativity between various electrode positions was observed. We suggest that these changes in potential size during the process of motor learning may reflect an altered cortical organisation of movement control during the acquisition of a complex motor task. PMID:1893989

  17. The NF90-NF45 Complex Functions as a Negative Regulator in the MicroRNA Processing Pathway▿ †

    PubMed Central

    Sakamoto, Shuji; Aoki, Kazuma; Higuchi, Takuma; Todaka, Hiroshi; Morisawa, Keiko; Tamaki, Nobuyuki; Hatano, Etsuro; Fukushima, Atsuki; Taniguchi, Taketoshi; Agata, Yasutoshi

    2009-01-01

    The positive regulatory machinery in the microRNA (miRNA) processing pathway is relatively well characterized, but negative regulation of the pathway is largely unknown. Here we show that a complex of nuclear factor 90 (NF90) and NF45 proteins functions as a negative regulator in miRNA biogenesis. Primary miRNA (pri-miRNA) processing into precursor miRNA (pre-miRNA) was inhibited by overexpression of the NF90 and NF45 proteins, and considerable amounts of pri-miRNAs accumulated in cells coexpressing NF90 and NF45. Treatment of cells overexpressing NF90 and NF45 with an RNA polymerase II inhibitor, α-amanitin, did not reduce the amounts of pri-miRNAs, suggesting that the accumulation of pri-miRNAs is not due to transcriptional activation. In addition, the NF90 and NF45 complex was not found to interact with the Microprocessor complex, which is a processing factor of pri-miRNAs, but was found to bind endogenous pri-miRNAs. NF90-NF45 exhibited higher binding activity for pri-let-7a than pri-miR-21. Of note, depletion of NF90 caused a reduction of pri-let-7a and an increase of mature let-7a miRNA, which has a potent antiproliferative activity, and caused growth suppression of transformed cells. These findings suggest that the association of the NF90-NF45 complex with pri-miRNAs impairs access of the Microprocessor complex to the pri-miRNAs, resulting in a reduction of mature miRNA production. PMID:19398578

  18. Negative Pressure Wound Therapy (NPWT) to Treat Complex Defect of the Leg after Electrical Burn.

    PubMed

    Tevanov, Iulia; Enescu, Dan M; Bălănescu, Radu; Sterian, G; Ulici, Alexandru

    2016-01-01

    Negative pressure wound therapy is a non-invasive treatment that uses under atmospheric pressure to increase blood supply to the wound, stimulating the formation of granulation tissue, angiogenesis, proliferation of fibroblasts and endothelial cells. Negative pressure therapy has also the ability to decrease the bacterial load, reduce swelling and decrease exudate while maintaining a moist environment that facilitates healing. Our patient, a 17 year old male, suffered major third and fourth-degree high voltage electrical burns on 60% of the body surface, in November 2011. After the excision of the necrotic tissue (muscles and tendons), the lower extremity of the right leg- the tibial bone, the fibula, external and internal malleoli became exposed circularly. The soft-tissue defect was partially covered by using an internal twin muscle flap and free split skin. Then, a cross leg flap technique has been used, partially covering the defect with a contralateral thigh flap. Surface swab cultures were positive for Pseudomonas aeruginosa. In October 2013 the patient was transferred to our department. The clinical examination of the right leg showed that the tibial bone had been exposed on an area of 15/3 cm in the lower half. The peroneal malleolus had also been exposed. The resection of the devitalized, exposed tibia and the avivement of the wound edges were performed. Then the NPWT was started and performed by intermittent suction. Local cleansing, soft-tissue avivement and dressing changes were performed twice a week for 6 weeks. After six weeks of NPWT and eleven dressing changes under general anaesthesia, the wounds were ready for skin grafting. Granulation tissue was formed, covering the entire surface of both the tibia bone and the peroneal malleolus. Both receptor beds were covered with free skin graft harvested from the ipsilateral thigh. The mechanical suture of the skin grafts was performed and the grafts were covered with damp dressing. By using the NPWT it

  19. Rem2 Is an Activity-Dependent Negative Regulator of Dendritic Complexity In Vivo

    PubMed Central

    Ghiretti, Amy E.; Moore, Anna R.; Brenner, Rebecca G.; Chen, Liang-Fu; West, Anne E.; Lau, Nelson C.; Van Hooser, Stephen D.

    2014-01-01

    A key feature of the CNS is structural plasticity, the ability of neurons to alter their morphology and connectivity in response to sensory experience and other changes in the environment. How this structural plasticity is achieved at the molecular level is not well understood. We provide evidence that changes in sensory experience simultaneously trigger multiple signaling pathways that either promote or restrict growth of the dendritic arbor; structural plasticity is achieved through a balance of these opposing signals. Specifically, we have uncovered a novel, activity-dependent signaling pathway that restricts dendritic arborization. We demonstrate that the GTPase Rem2 is regulated at the transcriptional level by calcium influx through L-VGCCs and inhibits dendritic arborization in cultured rat cortical neurons and in the Xenopus laevis tadpole visual system. Thus, our results demonstrate that changes in neuronal activity initiate competing signaling pathways that positively and negatively regulate the growth of the dendritic arbor. It is the balance of these opposing signals that leads to proper dendritic morphology. PMID:24403140

  20. Quantum effects in electron emission from and accretion on negatively charged spherical particles in a complex plasma

    SciTech Connect

    Mishra, S. K.; Sodha, M. S.; Misra, Shikha

    2012-07-15

    The authors have investigated the electron emissions (thermionic, electric field, photoelectric, and light induced field) from and electron accretion on a charged particle in a complex plasma, on the basis of a three region electrical potential model in and around a charged spherical particle in a complex plasma, characterized by Debye shielding. A continuous variation of the transmission coefficient across the surface of a particle (corresponding to emission and accretion) with the radial electron energy {epsilon}{sub r} has been obtained. It is seen that the numerical values of the emission and accretion transmission coefficients [D({epsilon}{sub r})] are almost the same. This is the necessary and sufficient condition for the validity of Saha's equation for thermal equilibrium of a system of dust and electrons. This is in contrast to the earlier condition, which limited the range of validity of Saha's equation to the range of the applicability of Born approximation. It is seen that D({epsilon}{sub r}) increases with increasing {epsilon}{sub r}, increasing negative electric potential on the surface, decreasing radius, and deceasing Debye length. The electron currents, corresponding to thermionic, electric field, photoelectric and light induced field emission increase with increasing surface potential; this fact may have significant repercussions in complex plasma kinetics. Since numerically D({epsilon}{sub r}) is significantly different from unity in the range of {epsilon}{sub r} of interest, it is necessary to take into account the D({epsilon}{sub r})-{epsilon}{sub r} dependence in complex plasma theory.

  1. Reducing Complexity: A Regularized Non-negative Matrix Approximation (NNMA) Approach to X-ray Spectromicroscopy Analysis

    NASA Astrophysics Data System (ADS)

    Mak, Rachel Y. C.

    2014-09-01

    X-ray absorption spectromicroscopy combines microscopy and spectroscopy to provide rich information about the chemical organization of materials down to the nanoscale. But with richness also comes complexity: natural materials such as biological or environmental science specimens can be composed of complex spectroscopic mixtures of different materials. The challenge becomes how we could meaningfully simplify and interpret this information. Approaches such as principal component analysis and cluster analysis have been used in previous studies, but with some limitations that we will describe. This leads us to develop a new approach based on a development of non-negative matrix approximation (NNMA) analysis with both sparseness and spectra similarity regularizations. We apply this new technique to simulated spectromicroscopy datasets as well as a preliminary study of the large-scale biochemical organization of a human sperm cell. NNMA analysis is able to select major features of the sperm cell without the physically erroneous negative weightings or thicknesses in the calculated image which appeared in previous approaches.

  2. Negative hyperconjugation and red-, blue- or zero-shift in X-Z∙∙∙Y complexes.

    PubMed

    Joy, Jyothish; Jemmis, Eluvathingal D; Vidya, Kaipanchery

    2015-01-01

    A generalized explanation is provided for the existence of the red- and blue-shifting nature of X-Z bonds (Z=H, halogens, chalcogens, pnicogens, etc.) in X-Z∙∙∙Y complexes based on computational studies on a selected set of weakly bonded complexes and analysis of existing literature data. The additional electrons and orbitals available on Z in comparison to H make for dramatic differences between the H-bond and the rest of the Z-bonds. The nature of the X-group and its influence on the X-Z bond length in the parent X-Z molecule largely controls the change in the X-Z bond length on X-Z∙∙∙Y bond formation; the Y-group usually influences only the magnitude of the effects controlled by X. The major factors which control the X-Z bond length change are: (a) negative hyperconjugative donation of electron density from X-group to X-Z σ* antibonding molecular orbital (ABMO) in the parent X-Z, (b) induced negative hyperconjugation from the lone pair of electrons on Z to the antibonding orbitals of the X-group, and (c) charge transfer (CT) from the Y-group to the X-Z σ* orbital. The exchange repulsion from the Y-group that shifts partial electron density at the X-Z σ* ABMO back to X leads to blue-shifting and the CT from the Y-group to the σ* ABMO of X-Z leads to red-shifting. The balance between these two opposing forces decides red-, zero- or blue-shifting. A continuum of behaviour of X-Z bond length variation is inevitable in X-Z∙∙∙Y complexes. PMID:25653178

  3. Genetic evaluation of BRCA1-A complex genes with triple-negative breast cancer susceptibility in Chinese women

    PubMed Central

    Zheng, Yi-Zi; Qiao, Feng; Yao, Ling; Cao, Zhi-Gang; Ye, Fu-Gui; Wu, Jiong; Hu, Xin; Wang, Bin; Shao, Zhi-Ming

    2016-01-01

    Background The tumor suppressor BRCA1 plays a pivotal role in maintaining genomic stability and tumor suppression. The BRCA1-A complex is required for recruitment of BRCA1 to DNA damage sites, DNA repair and cell cycle checkpoint control. Since germline mutations of BRCA1 often lead to breast tumors that are triple-negative breast cancer (TNBC) type, we aimed to investigate whether genetic deficiency in genes of the BRCA1-A complex is associated with risk to TNBC development. Results We found that rs7250266 in the promoter region of NBA1 confers a decreased risk to TNBC development, but not to non-TNBC susceptibility. In addition, the haplotypes containing two polymorphisms rs7250266 and rs2278256 are associated with a lower chance of TNBC development specifically. Our studies also showed that the protective alleles of rs7250266 (C > G) and rs2278256 (T > C) down-regulate promoter activity of NBA1 in mammary epithelial cells. Methods We investigated associations between the BRCA1-A complex genes and TNBC developing risk in first case-control study of Chinese Han Women population including 414 patients with TNBC and 354 cancer-free controls. We detected 37 common variants in ABRAXAS, RAP80, BRE, BRCC36 and NBA1/MERIT40 genes encoding the BRCA1-A complex and evaluated their genetic susceptibility to the risk of TNBC. An additional cohort with 652 other types of breast cancer (non-TNBC) cases and 890 controls was used to investigate the associations between TNBC-specific SNPs genotype and non-TNBCs susceptibility. Conclusions Genetic variants in NBA1 may be an important genetic determinant of TNBC susceptibility. Further investigation and validation of these SNPs in larger cohorts may facilitate in predication and prevention of TNBC and in counseling individuals for risk of TNBC development. PMID:26848770

  4. Cyclophilin E Functions as a Negative Regulator to Influenza Virus Replication by Impairing the Formation of the Viral Ribonucleoprotein Complex

    PubMed Central

    Wang, Zengfu; Liu, Xiaoling; Zhao, Zhendong; Xu, Chongfeng; Zhang, Ke; Chen, Caiwei; Sun, Lei; Gao, George F.; Ye, Xin; Liu, Wenjun

    2011-01-01

    Background The nucleoprotein (NP) of influenza A virus is a multifunctional protein that plays a critical role in the replication and transcription of the viral genome. Therefore, examining host factors that interact with NP may shed light on the mechanism of host restriction barriers and the tissue tropism of influenza A virus. Here, Cyclophilin E (CypE), a member of the peptidyl-propyl cis-trans isomerase (PPIase) family, was found to bind to NP and inhibit viral replication and transcription. Methodology/Principal Findings In the present study, CypE was found to interact with NP but not with the other components of the viral ribonucleoprotein complex (vRNP): PB1, PB2, and PA. Mutagenesis data revealed that the CypE domain comprised of residues 137–186 is responsible for its binding to NP. Functional analysis results indicated that CypE is a negative regulator in the influenza virus life cycle. Furthermore, knock-down of CypE resulted in increased levels of three types of viral RNA, suggesting that CypE negatively affects viral replication and transcription. Moreover, up-regulation of CypE inhibited the activity of influenza viral polymerase. We determined that the molecular mechanism by which CypE negatively regulates influenza virus replication and transcription is by interfering with NP self-association and the NP-PB1 and NP-PB2 interactions. Conclusions/Significance CypE is a host restriction factor that inhibits the functions of NP, as well as viral replication and transcription, by impairing the formation of the vRNP. The data presented here will help us to better understand the molecular mechanisms of host restriction barriers, host adaptation, and tissue tropism of influenza A virus. PMID:21887220

  5. Forskolin-inducible cAMP Pathway Negatively Regulates T-cell Proliferation by Uncoupling the Interleukin-2 Receptor Complex*

    PubMed Central

    Rodriguez, Georgialina; Ross, Jeremy A.; Nagy, Zsuzsanna S.; Kirken, Robert A.

    2013-01-01

    Cytokine-mediated regulation of T-cell activity involves a complex interplay between key signal transduction pathways. Determining how these signaling pathways cross-talk is essential to understanding T-cell function and dysfunction. In this work, we provide evidence that cross-talk exists between at least two signaling pathways: the Jak3/Stat5 and cAMP-mediated cascades. The adenylate cyclase activator forskolin (Fsk) significantly increased intracellular cAMP levels and reduced proliferation of the human T-cells via inhibition of cell cycle regulatory genes but did not induce apoptosis. To determine this inhibitory mechanism, effects of Fsk on IL-2 signaling was investigated. Fsk treatment of MT-2 and Kit 225 T-cells inhibited IL-2-induced Stat5a/b tyrosine and serine phosphorylation, nuclear translocation, and DNA binding activity. Fsk treatment also uncoupled IL-2 induced association of the IL-2Rβ and γc chain, consequently blocking Jak3 activation. Interestingly, phosphoamino acid analysis revealed that Fsk-treated cells resulted in elevated serine phosphorylation of Jak3 but not Stat5, suggesting that Fsk can negatively regulate Jak3 activity possibly mediated through PKA. Indeed, in vitro kinase assays and small molecule inhibition studies indicated that PKA can directly serine phosphorylate and functionally inactivate Jak3. Taken together, these findings suggest that Fsk activation of adenylate cyclase and PKA can negatively regulate IL-2 signaling at multiple levels that include IL-2R complex formation and Jak3/Stat5 activation. PMID:23341462

  6. SAPCD2 Controls Spindle Orientation and Asymmetric Divisions by Negatively Regulating the Gαi-LGN-NuMA Ternary Complex.

    PubMed

    Chiu, Catherine W N; Monat, Carine; Robitaille, Mélanie; Lacomme, Marine; Daulat, Avais M; Macleod, Graham; McNeill, Helen; Cayouette, Michel; Angers, Stéphane

    2016-01-11

    Control of cell-division orientation is integral to epithelial morphogenesis and asymmetric cell division. Proper spatiotemporal localization of the evolutionarily conserved Gαi-LGN-NuMA protein complex is critical for mitotic spindle orientation, but how this is achieved remains unclear. Here we identify Suppressor APC domain containing 2 (SAPCD2) as a previously unreported LGN-interacting protein. We show that SAPCD2 is essential to instruct planar mitotic spindle orientation in both epithelial cell cultures and mouse retinal progenitor cells in vivo. Loss of SAPCD2 randomizes spindle orientation, which in turn disrupts cyst morphogenesis in three-dimensional cultures, and triples the number of terminal asymmetric cell divisions in the developing retina. Mechanistically, we show that SAPCD2 negatively regulates the localization of LGN at the cell cortex, likely by competing with NuMA for its binding. These results uncover SAPCD2 as a key regulator of the ternary complex controlling spindle orientation during morphogenesis and asymmetric cell divisions. PMID:26766442

  7. Synthetic quantitative array technology identifies the Ubp3-Bre5 deubiquitinase complex as a negative regulator of mitophagy.

    PubMed

    Müller, Matthias; Kötter, Peter; Behrendt, Christina; Walter, Elena; Scheckhuber, Christian Q; Entian, Karl-Dieter; Reichert, Andreas S

    2015-02-24

    Mitophagy is crucial to ensuring mitochondrial quality control. However, the molecular mechanism and regulation of mitophagy are still not fully understood. Here, we developed a quantitative methodology termed synthetic quantitative array (SQA) technology, which allowed us to perform a genome-wide screen for modulators of rapamycin-induced mitophagy in S. cerevisiae. SQA technology can be easily employed for other enzyme-based reporter systems and widely applied in yeast research. We identified 86 positive and 10 negative regulators of mitophagy. Moreover, SQA-based analysis of non-selective autophagy revealed that 63 of these regulators are specific for mitophagy and 33 regulate autophagy in general. The Ubp3-Bre5 deubiquitination complex was found to inhibit mitophagy but, conversely, to promote other types of autophagy, including ribophagy. This complex translocates dynamically to mitochondria upon induction of mitophagy. These findings point to a role of ubiquitination in mitophagy in yeast and suggest a reciprocal regulation of distinct autophagy pathways. PMID:25704822

  8. Auditory scene analysis and sonified visual images. Does consonance negatively impact on object formation when using complex sonified stimuli?

    PubMed Central

    Brown, David J.; Simpson, Andrew J. R.; Proulx, Michael J.

    2015-01-01

    A critical task for the brain is the sensory representation and identification of perceptual objects in the world. When the visual sense is impaired, hearing and touch must take primary roles and in recent times compensatory techniques have been developed that employ the tactile or auditory system as a substitute for the visual system. Visual-to-auditory sonifications provide a complex, feature-based auditory representation that must be decoded and integrated into an object-based representation by the listener. However, we don’t yet know what role the auditory system plays in the object integration stage and whether the principles of auditory scene analysis apply. Here we used coarse sonified images in a two-tone discrimination task to test whether auditory feature-based representations of visual objects would be confounded when their features conflicted with the principles of auditory consonance. We found that listeners (N = 36) performed worse in an object recognition task when the auditory feature-based representation was harmonically consonant. We also found that this conflict was not negated with the provision of congruent audio–visual information. The findings suggest that early auditory processes of harmonic grouping dominate the object formation process and that the complexity of the signal, and additional sensory information have limited effect on this. PMID:26528202

  9. Auditory scene analysis and sonified visual images. Does consonance negatively impact on object formation when using complex sonified stimuli?

    PubMed

    Brown, David J; Simpson, Andrew J R; Proulx, Michael J

    2015-01-01

    A critical task for the brain is the sensory representation and identification of perceptual objects in the world. When the visual sense is impaired, hearing and touch must take primary roles and in recent times compensatory techniques have been developed that employ the tactile or auditory system as a substitute for the visual system. Visual-to-auditory sonifications provide a complex, feature-based auditory representation that must be decoded and integrated into an object-based representation by the listener. However, we don't yet know what role the auditory system plays in the object integration stage and whether the principles of auditory scene analysis apply. Here we used coarse sonified images in a two-tone discrimination task to test whether auditory feature-based representations of visual objects would be confounded when their features conflicted with the principles of auditory consonance. We found that listeners (N = 36) performed worse in an object recognition task when the auditory feature-based representation was harmonically consonant. We also found that this conflict was not negated with the provision of congruent audio-visual information. The findings suggest that early auditory processes of harmonic grouping dominate the object formation process and that the complexity of the signal, and additional sensory information have limited effect on this. PMID:26528202

  10. Linear free energy relationships for metal-ligand complexation: Bidentate binding to negatively-charged oxygen donor atoms

    NASA Astrophysics Data System (ADS)

    Carbonaro, Richard F.; Atalay, Yasemin B.; Di Toro, Dominic M.

    2011-05-01

    Stability constants for metal complexation to bidentate ligands containing negatively-charged oxygen donor atoms can be estimated from the following linear free energy relationship (LFER): log KML = χOO( αO log KHL,1 + αO log KHL,2) where KML is the metal-ligand stability constant for a 1:1 complex, KHL,1 and KHL,2 are the proton-ligand stability constants (the ligand p Ka values), and αO is the Irving-Rossotti slope. The parameter χOO is metal specific and has slightly different values for five and six membered chelate rings. LFERs are presented for 21 different metal ions and are accurate to within approximately 0.30 log units in predictions of log KML values. Ligands selected for use in LFER development include dicarboxylic acids, carboxyphenols, and ortho-diphenols. For ortho-hydroxybenzaldehydes, α-hydroxycarboxylic acids, and α-ketocarboxylic acids, a modification of the LFER where log KHL,2 is set equal to zero is required. The chemical interpretation of χOO is that it accounts for the extra stability afforded to metal complexes by the chelate effect. Cu-NOM binding constants calculated from the bidentate LFERs are similar in magnitude to those used in WHAM 6. This LFER can be used to make log KML predictions for small organic molecules. Since natural organic matter (NOM) contains many of the same functional groups (i.e. carboxylic acids, phenols, alcohols), the LFER log KML predictions shed light on the range of appropriate values for use in modeling metal partitioning in natural systems.

  11. Array-based identification of triple-negative breast cancer cells using fluorescent nanodot-graphene oxide complexes.

    PubMed

    Tao, Yu; Auguste, Debra T

    2016-07-15

    Early and accurate diagnosis of breast cancer holds great promise to improve treatability and curability. Here, we report the usage of six luminescent nanodot-graphene oxide complexes as novel fluorescent nanoprobes in a sensing array capable of effectively identifying healthy, cancerous, and metastatic human breast cells. The sensory system is based on the utilization of nanoprobe-graphene oxide sensor elements that can be disrupted in the presence of breast cells to give fluorescent readouts. Using this multichannel sensor, we have successfully identified breast cancer cells and distinguished between estrogen receptor positive, human epidermal growth factor receptor-2 positive, and triple negative phenotypes. This approach also allows cell identification at high sensitivity (200 cells) with high reproducibility. The unknown cell sample analysis indicates that the sensor is able to identify 49 out of 50 breast cell samples correctly, with a detection accuracy of 98%. Taken together, this array-based luminescent nanoprobe-graphene oxide sensing platform presents a useful cell screening tool with potential applications in biomedical diagnostics. PMID:27003608

  12. The nascent-polypeptide-associated complex alpha subunit regulates the polygalacturonases expression negatively and influences the pathogenicity of Sclerotinia sclerotiorum.

    PubMed

    Li, Xiuli; Guo, Min; Xu, Dafeng; Chen, Fangxin; Zhang, Huajian; Pan, Yuemin; Li, Maomao; Gao, Zhimou

    2015-01-01

    Sclerotinia sclerotiorum is a necrotrophic plant-pathogenic fungus that infects more than 400 species of plants. In this study the nascent polypeptide-associated complex α subunit gene of S. sclerotiorum (SsNACα; accession No. XP_001593856.1) was cloned and characterized. The relative transcript expression of SsNACα at different morphological stages of asexual development of S. sclerotiorum were analyzed by quantitative real time PCR (qRT-PCR). RNAi-mediated gene silencing was successful for SsNACα, and the mutated strains exhibited less than 15% of the relative expression of SsNACα were obtained and used for studying the biological functions of the gene. A delay in sclerotial maturation for S. sclerotiorum was observed in the SsNACα mutants. The significant elevations for both the activities of pectin-degrading enzymes and the expression of polygalacturonase genes also were associated with the mutated strains, indicating that SsNACα could negatively influence polygalacturonases expression and modulate the pathogenicity of S. sclerotiorum. PMID:26297780

  13. Spoligotype profile of Mycobacterium tuberculosis complex strains from HIV-positive and -negative patients in Nigeria: a comparative analysis.

    PubMed

    Cadmus, Simeon; Hill, Véronique; van Soolingen, Dick; Rastogi, Nalin

    2011-01-01

    We ran a comparative analysis of all patients for whom a positive culture of Mycobacterium tuberculosis complex was available between April 2004 and October 2005 and whose HIV serology results were known, with spoligotyping results (n = 163) split into 49 HIV-positive patients and 114 HIV-negative patients. Spoligotype international type 373 (SIT373) (T1 lineage), which was highly prevalent among the HIV(+) patients, was totally absent from the HIV(-) population, suggesting that we had a specific clone affecting nearly 1/3 of all HIV-tuberculosis (TB)-coinfected patients. Among the LAM10-CAM sublineage strains, we had only a single strain of SIT403 among HIV(-) patients (0.88%), as opposed to 12.25% of the HIV(+) population (χ(2) = 10.77; P < 0.01), indicating a strong association between the strain and the HIV(+) population. The LAM10-CAM lineage spoligotype SIT61 was prevalent among the 2 subsets (37.72% in HIV(-) versus 12.24% in HIV(+) populations), though, with a significant difference between the 2 groups (χ(2) = 10.53; P < 0.01). However, there was no significant difference for SIT53 (T1 lineage) in the 2 subsets: 6.14 versus 8.2% (χ(2) = 0.22; P > 0.05). A total of 7/49, or 14.3%, other SITs among HIV(+) patients were not found among the HIV(-) patients. When added to the most prevalent SIT among HIV(+) patients (SIT373; n = 16), 23/49, or 47%, isolates among HIV-TB-coinfected patients were unique. We conclude that further studies should be carried out to investigate the evolution of these genotypes and others in the emergence of multidrug resistance and control of tuberculosis in Nigeria. PMID:21048016

  14. Combined use of negative pressure wound therapy and Integra® to treat complex defects in lower extremities after burns

    PubMed Central

    González Alaña, I.; Torrero López, J.V.; Martín Playá, P.; Gabilondo Zubizarreta, F.J.

    2013-01-01

    Summary Deep and extensive burns of lower extremities present a difficult challenge to healthcare professionals. After debridement, bones, tendons or joints are frequently exposed and cannot be covered by simple autografts. Moreover, in the case of major burns, damage to the surrounding areas of skin and the severity of the patient’s overall condition, often count against using pedicled or microsurgical flaps. In dealing with such complex wounds, which are difficult to treat, several authors have recommended the combined use of Integra® and negative pressure wound therapy (NPWT). They emphasize that NPWT eliminates wound exudate, promotes neovascularisation and cell migration through the Integra® matrix while increasing its stability and adherence to the wound bed, as well as decreasing the time needed for its total integration. The case presented here is of a patient with major third-degree flame burns to the lower extremities. After debridement, the external and internal malleolus bilaterally became exposed as well as the partially debrided tendons (Achilles, extensor digitorum longus, long and short peroneus, anterior and posterior tibialis). After ruling out the use of local or microsurgical flaps due to the patient’s poor general condition and the presence of burns debrided to the fascia over both lower extremities, we elected to manage the patient with a combined treatment using Integra® and NPWT. After three weeks of treatment, the surface layer of the Integra® matrix was replaced with autografts. Due to partial loss of the skin grafts, a second autograft was needed. At present the patient is completely healed; he can walk with full flexion-extension of both ankles. PMID:24133403

  15. False-negative indocyanine green videoangiography among complex unruptured middle cerebral artery aneurysms: the importance of further aneurysm inspection.

    PubMed

    Kulwin, Charles; Cohen-Gadol, Aaron A

    2014-10-01

    Successful surgical treatment of cerebral aneurysms requires complete occlusion of the aneurysm lumen while maintaining patency of the adjacent branching and perforating arteries. Intraoperative flow assessment allows aneurysm clip repositioning in the event these requirements are not met, avoiding the risk of postoperative rehemorrhage or infarction. A number of modalities have been proposed for primarily intraoperative qualitative blood flow assessment, including microdoppler ultrasonography, intraoperative digital subtraction angiography (DSA), and more recently noninvasive fluorescent angiography including indocyanine green (ICG) fluorescent imaging. Puncture of the aneurysm dome to exclude aneurysm sac filling may also assess the efficacy of clip placement. Although a high concordance between ICG and DSA has been reported, there remains an important subset of aneurysms for which negative ICG study may erroneously suggest aneurysm occlusion. A high-risk situation for such a false-negative study is an atherosclerotic middle cerebral artery (MCA) aneurysm in which vessel wall plaque interferes with the ICG signal. Furthermore, a decreased flow within the aneurysm may not allow enough emission light for detection under the current technology. In this report, we describe our experience with cases of MCA aneurysms with false-negative ICG-VA studies requiring clip adjustment for optimal surgical treatment and discuss two illustrative cases of MCA aneurysms with intraoperative fluorescence studies that were falsely negative, requiring puncture of the aneurysm to correctly identify incomplete aneurysm occlusion. PMID:24552255

  16. The Enok acetyltransferase complex interacts with Elg1 and negatively regulates PCNA unloading to promote the G1/S transition.

    PubMed

    Huang, Fu; Saraf, Anita; Florens, Laurence; Kusch, Thomas; Swanson, Selene K; Szerszen, Leanne T; Li, Ge; Dutta, Arnob; Washburn, Michael P; Abmayr, Susan M; Workman, Jerry L

    2016-05-15

    KAT6 histone acetyltransferases (HATs) are highly conserved in eukaryotes and are involved in cell cycle regulation. However, information regarding their roles in regulating cell cycle progression is limited. Here, we report the identification of subunits of the Drosophila Enok complex and demonstrate that all subunits are important for its HAT activity. We further report a novel interaction between the Enok complex and the Elg1 proliferating cell nuclear antigen (PCNA)-unloader complex. Depletion of Enok in S2 cells resulted in a G1/S cell cycle block, and this block can be partially relieved by depleting Elg1. Furthermore, depletion of Enok reduced the chromatin-bound levels of PCNA in both S2 cells and early embryos, suggesting that the Enok complex may interact with the Elg1 complex and down-regulate its PCNA-unloading function to promote the G1/S transition. Supporting this hypothesis, depletion of Enok also partially rescued the endoreplication defects in Elg1-depleted nurse cells. Taken together, our study provides novel insights into the roles of KAT6 HATs in cell cycle regulation through modulating PCNA levels on chromatin. PMID:27198229

  17. Earlier timbre processing of instrumental tones compared to equally complex spectrally rotated sounds as revealed by the mismatch negativity.

    PubMed

    Christmann, Corinna A; Lachmann, Thomas; Berti, Stefan

    2014-10-01

    Harmonically rich sounds have been shown to be processed more efficiently by the human brain compared to single sinusoidal tones. To control for stimulus complexity as a potentially confounding factor, tones and equally complex spectrally rotated sounds, have been used in the present study to investigate the role of the overtone series in sensory auditory processing in non-musicians. Timbre differences in instrumental tones with equal pitch elicited a MMN which was earlier compared to that elicited by the spectrally rotated sounds, indicating that harmonically rich tones are processed faster compared to non-musical sounds without an overtone series, even when pitch is not the relevant information. PMID:25173970

  18. Immune complex disease with a lupus-like pattern of deposition in an antinuclear antibody-negative patient.

    PubMed

    Pirkle, James L; Freedman, Barry I; Fogo, Agnes B

    2013-07-01

    Immune complex-mediated glomerulonephritis can be caused by a multitude of disease processes and may manifest in a variety of histologic patterns. Lupus nephritis is an immune complex disease, the diagnosis of which requires that the affected patient have systemic lupus erythematosus (SLE). In the absence of SLE, the finding of glomerulonephritis with certain patterns of immune complex deposition characteristic of lupus nephritis has been referred to as lupus-like glomerulonephritis. Immunoglobulin G (IgG), IgA, IgM, complement C3, and C1q deposition in glomerular immune deposits is one such pattern. We report a case of immune complex disease in a primarily membranous distribution with mesangial, subendothelial, and tubular basement membrane deposits with IgG, IgA, IgM, C3, and C1q deposition in a patient with proteinuria, photosensitive dermatitis, and a positive lupus anticoagulant test. The patient had 3 of the clinical criteria for SLE, thus failing to meet the diagnosis based on the American College of Rheumatology definition. In this case, a diagnosis of lupus-like glomerulonephritis was made after other causes of membranous glomerulopathy were excluded. This teaching case highlights the broad differential diagnosis of this pattern of injury and reviews similar cases in the literature. PMID:23548558

  19. Spin-filtering, giant magnetoresistance, rectifying and negative differential resistance effects in planar four-coordinate Fe complex with graphene nanoribbon electrodes

    SciTech Connect

    Zhao, P. E-mail: ss-cheng@ujn.edu.cn; Wu, Q. H.; Chen, G. E-mail: ss-cheng@ujn.edu.cn; Liu, D. S.; Department of Physics, Jining University, Qufu 273155

    2014-01-28

    By using the nonequilibrium Green's function formalism combined with the density functional theory, we have investigated the spin-polarized transport properties of a planar four-coordinate Fe complex sandwiched between two zigzag-edge graphene nanoribbon (ZGNR) electrodes, where the ZGNRs are modulated by external magnetic field. The results show that the system can exhibit perfect dual spin-filtering and spin-rectifying effects at a wide bias range, giant magnetoresistance effect with large magnetoresistance ratio at small bias, and obvious negative differential resistance behavior. The mechanisms are proposed for these phenomena.

  20. Septic arthritis caused by a gram-negative bacterium representing a new species related to the Bordetella-Alcaligenes complex.

    PubMed

    Kronvall, G; Hanson, H S; von Stedingk, L V; Törnqvist, E; Falsen, E

    2000-03-01

    A knee-joint exudate culture yielded on two occasions a gram-negative bacterium. Regular methods for speciation did not provide an identification. The infection was successfully treated with ciprofloxacin. The unknown isolate, CCUG 36768, was subjected to further investigation, including 16S rDNA sequencing, protein profiling, cellular fatty acid analysis, and various biochemical tests, in order to produce a species identification. The 1469 bp-long 16S rDNA sequence did not reveal identity with any known species sequence. CCUG 36768 clustered in a group of species, including Alcaligenes defragrans, Denitrobacter permanens, Taylorella equigenitalis, Alcaligenes faecalis, and four strains of Alcaligenes species without a specific species name. Bordetella species also showed a high degree of similarity with CCUG 36768. Protein profiling, cellular fatty acid analysis and computer-assisted analysis of biochemical profiles indicated similarity with Bordetella-Alcaligenes species, often close to B. holmesii and B. avium. API 20 NE indicated the profile of Moraxella species of poor identity. It is concluded that CCUG 36768 represents a new bacterial species of pathogenic potential in humans. It is related to the Bordetella-Alcaligenes group. Powerful new methods for speciation are available and it is recommended that unknown isolates from normally sterile sites be submitted for further analysis. Several isolates are required for the definition of new species. PMID:10752687

  1. Genomic complexity profiling reveals that HORMAD1 overexpression contributes to homologous recombination deficiency in triple-negative breast cancers

    PubMed Central

    Watkins, Johnathan; Weekes, Daniel; Shah, Vandna; Gazinska, Patrycja; Joshi, Shalaka; Sidhu, Bhavna; Gillett, Cheryl; Pinder, Sarah; Vanoli, Fabio; Jasin, Maria; Mayrhofer, Markus; Isaksson, Anders; Cheang, Maggie C.U.; Mirza, Hasan; Frankum, Jessica; Lord, Christopher J.; Ashworth, Alan; Vinayak, Shaveta; Ford, James M.; Telli, Melinda L.; Grigoriadis, Anita; Tutt, Andrew N.J.

    2015-01-01

    Triple-negative breast cancers (TNBCs) are characterised by a wide spectrum of genomic alterations, some of which might be caused by defects in DNA repair processes such as homologous recombination (HR). Despite this understanding, associating particular patterns of genomic instability with response to therapy has been challenging. Here, we show that Allelic-imbalanced Copy Number Aberrations (AiCNA) are more prevalent in TNBCs that respond to platinum-based chemotherapy, thus providing a candidate predictive biomarker for this disease. Furthermore, we show that a high level of AiCNA is linked with elevated expression of a meiosis-associated gene HORMAD1. Elevated HORMAD1 expression suppresses RAD51-dependent HR and drives the use of alternative forms of DNA repair, the generation of AiCNAs as well as sensitising cancer cells to HR targeting therapies. Our data therefore provides a mechanistic association between HORMAD1 expression, a specific pattern of genomic instability and an association with response to platinum-based chemotherapy in TNBC. PMID:25770156

  2. Favorable combination of positive and negative electrode materials with glyme-Li salt complex electrolytes in lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Orita, A.; Kamijima, K.; Yoshida, M.; Dokko, K.; Watanabe, M.

    Tetraglyme (G4)-lithium bis(trifluoromethanesulfonyl)amide (TFSA) complexes with different G4 ratio were investigated. An increase in the amount of G4 led to the decrease in the viscosity, and increase in the ionic conductivity of the complex, and G4-LiTFSA showed higher thermal stabilities than the conventional organic electrolyte, when the molar ratio of G4 was more than 40 mol%. The increase in the G4 amount improved the rate capabilities of Li/LiCoO 2 cells in the range where the molar ratio of G4 was between 40 mol% and 60 mol%. The stable Li ion intercalation-deintercalation was not observed in the Li/graphite cell of [Li(G4)][TFSA] (G4: 50 mol%) without additives. However, the additives for forming solid electrolyte interface (SEI) film, such as vinylene carbonate, vinylethylene carbonate, and 1,3-propane sultone, led to the charge-discharge performance comparable to that of the conventional organic electrolyte. The adoption of Li 4Ti 5O 12 and LiFePO 4 led to excellent reversibilities of the Li half cells using [Li(G4)][TFSA], probably because of the favorable operation voltage. In the case of the LiFePO 4/Li 4Ti 5O 12 cell, the cell with [Li(G4)][TFSA] showed the better rate capability than that with the conventional organic electrolyte, when the rate was less than 1 CmA, and it is concluded that [Li(G4)][TFSA] can be the candidate as the alternative of organic electrolytes when the most appropriate electrode-active materials are used.

  3. Linear ubiquitin assembly complex negatively regulates RIG-I and TRIM25 mediated type-I interferon induction

    PubMed Central

    Inn, Kyung-Soo; Gack, Michaela U.; Tokunaga, Fuminori; Shi, Mude; Wong, Lai-Yee; Iwai, Kazuhiro; Jung, Jae U.

    2011-01-01

    Summary Upon detection of viral RNA, retinoic acid inducible gene I (RIG-I) undergoes TRIM25-mediated Lys-63 linked ubiquitination, leading to type-I interferon (IFN) production. In this study, we demonstrate that the linear ubiquitin assembly complex (LUBAC), comprised of two RING-IBR-RING (RBR)-containing E3 ligases HOIL-1L and HOIP, independently targets TRIM25 and RIG-I to effectively suppress virus-induced IFN production. RBR E3 ligase domains of HOIL-1L and HOIP bind and induce proteosomal degradation of TRIM25, whereas the NZF domain of HOIL-1L competes with TRIM25 for RIG-I binding. Consequently, both actions by the HOIL-1L/HOIP LUBAC potently inhibit RIG-I ubiquitination and anti-viral activity, but in a mechanistically separate manner. Conversely, the genetic deletion or depletion of HOIL-1L and HOIP robustly enhances virus-induced type-I IFN production. Taken together, the HOIL-1L/HOIP LUBAC specifically suppresses RIG-I ubiquitination and activation by inducing TRIM25 degradation and inhibiting TRIM25 interaction with RIG-I, resulting in the comprehensive suppression of the IFN-mediated anti-viral signaling pathway. PMID:21292167

  4. Negatively charged Ir(iii) cyclometalated complexes containing a chelating bis-tetrazolato ligand: synthesis, photophysics and the study of reactivity with electrophiles.

    PubMed

    Fiorini, Valentina; Zacchini, Stefano; Raiteri, Paolo; Mazzoni, Rita; Zanotti, Valerio; Massi, Massimiliano; Stagni, Stefano

    2016-08-01

    The bis-tetrazolate dianion [1,2 BTB](2-), which is the deprotonated form of 1,2 bis-(1H-tetrazol-5-yl)benzene [1,2-H2BTB], is for the first time exploited as an ancillary N^N ligand for negatively charged [Ir(C^N)2(N^N)](-)-type complexes, where C^N is represented by cyclometalated 2-phenylpyridine (ppy) or 2-(2,4-difluorophenyl)pyridine (F2ppy). The new Ir(iii) complexes [Ir(ppy)2(1,2 BTB)]- and [Ir(F2ppy)2(1,2 BTB)]- have been fully characterised and the analysis of the X-ray structure of [Ir(ppy)2(1,2 BTB)]- confirmed the coordination of the [1,2 BTB](2-) dianion in a bis chelated fashion through the N-atoms adjacent to each of the tetrazolic carbons. Both of the new anionic Ir(iii) complexes displayed phosphorescence in the visible region, with intense sky-blue (λmax = 460-490 nm) or aqua (λmax = 490-520 nm) emissions originating from [Ir(F2ppy)2(1,2 BTB)]- and [Ir(ppy)2(1,2 BTB)]-, respectively. In comparison with our very recent examples of anionic Ir(iii)tetrazolate cyclometalates, the new Ir(iii) tris chelate complexes [Ir(F2ppy)2(1,2 BTB)]- and [Ir(ppy)2(1,2 BTB)]-, display an improved robustness, allowing the study of their reactivity toward the addition of electrophiles such as H(+) and CH3(+). In all cases, the electrophilic attacks occurred at the coordinated tetrazolate rings, involving the reversible - by a protonation deprotonation mechanism - or permanent - upon addition of a methyl moiety - switching of their global net charge from negative to positive and, in particular, the concomitant variation of their photoluminescence output. The combination of the anionic complexes [Ir(F2ppy)2(1,2 BTB)]- or [Ir(ppy)2(1,2 BTB)]- with a deep red emitting (λmax = 686 nm) cationic Ir(iii) tetrazole complex such as [IrTPYZ-Me]+, where TPYZ-Me is 2-(2-methyl-2H-tetrazol-5-yl)pyrazine, gave rise to two fully Ir(iii)-based soft salts capable of displaying additive and O2-sensitive emission colours, with an almost pure white light obtained by the appropriate

  5. Dominant-negative mutants of importin-beta block multiple pathways of import and export through the nuclear pore complex.

    PubMed Central

    Kutay, U; Izaurralde, E; Bischoff, F R; Mattaj, I W; Görlich, D

    1997-01-01

    Nuclear protein import proceeds through the nuclear pore complex (NPC). Importin-beta mediates translocation via direct interaction with NPC components and carries importin-alpha with the NLS substrate from the cytoplasm into the nucleus. The import reaction is terminated by the direct binding of nuclear RanGTP to importin-beta which dissociates the importin heterodimer. Here, we analyse the sites of interaction on importin-beta for its multiple partners. Ran and importin-alpha respectively require residues 1-364 and 331-876 of importin-beta for binding. Thus, RanGTP-mediated release of importin-alpha from importin-beta is likely to be an active displacement rather than due to simple competition between Ran and importin-alpha for a common binding site. Importin-beta has at least two non-overlapping sites of interaction with the NPC, which could potentially be used sequentially during translocation. Our data also suggest that termination of import involves a transient release of importin-beta from the NPC. Importin-beta fragments which bind to the NPC, but not to Ran, resist this release mechanism. As would be predicted from this, these importin-beta mutants are very efficient inhibitors of NLS-dependent protein import. Surprisingly, however, they also inhibit M9 signal-mediated nuclear import as well as nuclear export of mRNA, U snRNA, and the NES-containing Rev protein. This suggests that mediators of these various transport events share binding sites on the NPC and/or that mechanisms exist to coordinate translocation through the NPC via different nucleocytoplasmic transport pathways. PMID:9135132

  6. A Negative Feedback Loop Controlling bHLH Complexes Is Involved in Vascular Cell Division and Differentiation in the Root Apical Meristem.

    PubMed

    Katayama, Hirofumi; Iwamoto, Kuninori; Kariya, Yuka; Asakawa, Tomohiro; Kan, Toshiyuki; Fukuda, Hiroo; Ohashi-Ito, Kyoko

    2015-12-01

    Controlling cell division and differentiation in meristems is essential for proper plant growth. Two bHLH heterodimers consisting of LONESOME HIGHWAY (LHW) and TARGET OF MONOPTEROS 5 (TMO5)/TMO5-LIKE1 (T5L1) regulate periclinal cell division in vascular cells in the root apical meristem (RAM). In this study, we further investigated the functions of LHW-T5L1, finding that in addition to controlling cell division, this complex regulates xylem differentiation in the RAM via a novel negative regulatory system. LHW-T5L1 upregulated the thermospermine synthase gene ACAULIS5 (ACL5), as well as SUPPRESSOR OF ACAULIS5 LIKE3 (SACL3), which encodes a bHLH protein, in the RAM. The SACL3 promoter sequence contains a conserved upstream open reading frame (uORF), which blocked translation of the main SACL3 ORF in the absence of thermospermine. Thermospermine eliminated the negative effect of uORF and enhanced SACL3 production. Further genetic and molecular biological analyses indicated that ACL5 and SACL3 suppress the function of LHW-T5L1 through a protein-protein interaction between LHW and SACL3. Finally, we showed that a negative feedback loop consisting of LHW-T5L1, ACL5, SACL3, and LHW-SACL3 contributes to maintain RAM size and proper root growth. These findings suggest that a negative feedback loop regulates the LHW-T5L1 output level to coordinate cell division and differentiation in a cell-autonomous manner. PMID:26616019

  7. Dermal Fenestration With Negative Pressure Wound Therapy: A Technique for Managing Soft Tissue Injuries Associated With High-Energy Complex Foot Fractures.

    PubMed

    Poon, Henrietta; Le Cocq, Heather; Mountain, Alistair J; Sargeant, Ian D

    2016-01-01

    Military casualties can sustain complex foot fractures from blast incidents. This frequently involves the calcaneum and is commonly associated with mid-foot fracture dislocations. The foot is at risk of both compartment syndrome and the development of fracture blisters after such injuries. The amount of energy transfer and the environment in which the injury was sustained also predispose patients to potential skin necrosis and deep infection. Decompression of the compartments is a part of accepted practice in civilian trauma to reduce the risk of complications associated with significant soft tissue swelling. The traditional methods of foot fasciotomy, however, are not without significant complications. We report a simple technique of dermal fenestration combined with the use of negative pressure wound therapy, which aims to preserve the skin integrity of the foot without resorting to formal fasciotomy. PMID:26443232

  8. DNA-PK/Ku complex binds to latency-associated nuclear antigen and negatively regulates Kaposi's sarcoma-associated herpesvirus latent replication

    SciTech Connect

    Cha, Seho; Lim, Chunghun; Lee, Jae Young; Song, Yoon-Jae; Park, Junsoo; Choe, Joonho; Seo, Taegun

    2010-04-16

    During latent infection, latency-associated nuclear antigen (LANA) of Kaposi's sarcoma-associated herpesvirus (KSHV) plays important roles in episomal persistence and replication. Several host factors are associated with KSHV latent replication. Here, we show that the catalytic subunit of DNA protein kinase (DNA-PKcs), Ku70, and Ku86 bind the N-terminal region of LANA. LANA was phosphorylated by DNA-PK and overexpression of Ku70, but not Ku86, impaired transient replication. The efficiency of transient replication was significantly increased in the HCT116 (Ku86 +/-) cell line, compared to the HCT116 (Ku86 +/+) cell line, suggesting that the DNA-PK/Ku complex negatively regulates KSHV latent replication.

  9. Negative Ion Photoelectron Spectroscopy Reveals Remarkable Noninnocence of Ligands in Nickel Bis(dithiolene) Complexes [Ni(dddt)2](-) and [Ni(edo)2](.).

    PubMed

    Liu, Xing; Hou, Gao-Lei; Wang, Xuefeng; Wang, Xue-Bin

    2016-05-12

    [Ni(dddt)2](-) (dddt = 5,6-dihydro-1,4-dithiine-2,3-dithiolate) and [Ni(edo)2](-) (edo = 5,6-dihydro-1,4-dioxine-2,3-dithiolate) are two donor-type nickel bis(dithiolene) complexes, with the tendency of donating low binding energy electrons. These two structurally similar complexes differ only with respect to the outer atoms in the ligand framework where the former has four S atoms while the latter has four O atoms. Herein, we report a negative ion photoelectron spectroscopy (NIPES) study on these two complexes to probe the electronic structures of the anions and their corresponding neutrals. The NIPE spectra exhibit the adiabatic electron detachment energy (ADE) or, equivalently, the electron affinity (EA) of the neutral [Ni(L)2](0) to be relatively low for this type of complexes, 2.780 and 2.375 eV for L = dddt and edo, respectively. The 0.4 eV difference in ADEs shows a significant substitution effect for sulfur in dddt by oxygen in edo, i.e., noninnocence of the ligands, which has decreased the electronic stability of [Ni(edo)2](-) by lowering its electron binding energy by ∼0.4 eV. The observed substitution effect on gas-phase EA values correlates well with the measured redox potentials for [Ni(dddt)2](-/0) and [Ni(edo)2](-/0) in solutions. The singlet-triplet splitting (ΔEST) of [Ni(dddt)2](0) and [Ni(edo)2](0) is also determined from the spectra to be 0.57 and 0.53 eV, respectively. Accompanying DFT calculations and molecular orbital (MO) composition analyses show significant ligand contributions to the redox MOs and allow the components of the orbitals involved in each electronic transition and spectral assignments to be identified. PMID:27099986

  10. The THO/TREX Complex Active in miRNA Biogenesis Negatively Regulates Root-Associated Acid Phosphatase Activity Induced by Phosphate Starvation1[OPEN

    PubMed Central

    Tao, Sibo; Zhang, Ye; Wang, Xiaoyue; Xu, Le; Fang, Xiaofeng; Lu, Zhi John

    2016-01-01

    Induction and secretion of acid phosphatases (APases) is an adaptive response that plants use to cope with P (Pi) deficiency in their environment. The molecular mechanism that regulates this response, however, is poorly understood. In this work, we identified an Arabidopsis (Arabidopsis thaliana) mutant, hps8, which exhibits enhanced APase activity on its root surface (also called root-associated APase activity). Our molecular and genetic analyses indicate that this altered Pi response results from a mutation in the AtTHO1 gene that encodes a subunit of the THO/TREX protein complex. The mutation in another subunit of this complex, AtTHO3, also enhances root-associated APase activity under Pi starvation. In Arabidopsis, the THO/TREX complex functions in mRNA export and miRNA biogenesis. When treated with Ag+, an inhibitor of ethylene perception, the enhanced root-associated APase activity in hps8 is largely reversed. hpr1-5 is another mutant allele of AtTHO1 and shows similar phenotypes as hps8. ein2 is completely insensitive to ethylene. In the hpr1-5ein2 double mutant, the enhanced root-associated APase activity is also greatly suppressed. These results indicate that the THO/TREX complex in Arabidopsis negatively regulates root-associated APase activity induced by Pi starvation by inhibiting ethylene signaling. In addition, we found that the miRNA399-PHO2 pathway is also involved in the regulation of root-associated APase activity induced by Pi starvation. These results provide insight into the molecular mechanism underlying the adaptive response of plants to Pi starvation. PMID:27329222

  11. Inherited variants in the inner centromere protein (INCENP) gene of the chromosomal passenger complex contribute to the susceptibility of ER-negative breast cancer.

    PubMed

    Kabisch, Maria; Lorenzo Bermejo, Justo; Dünnebier, Thomas; Ying, Shibo; Michailidou, Kyriaki; Bolla, Manjeet K; Wang, Qin; Dennis, Joe; Shah, Mitul; Perkins, Barbara J; Czene, Kamila; Darabi, Hatef; Eriksson, Mikael; Bojesen, Stig E; Nordestgaard, Børge G; Nielsen, Sune F; Flyger, Henrik; Lambrechts, Diether; Neven, Patrick; Peeters, Stephanie; Weltens, Caroline; Couch, Fergus J; Olson, Janet E; Wang, Xianshu; Purrington, Kristen; Chang-Claude, Jenny; Rudolph, Anja; Seibold, Petra; Flesch-Janys, Dieter; Peto, Julian; dos-Santos-Silva, Isabel; Johnson, Nichola; Fletcher, Olivia; Nevanlinna, Heli; Muranen, Taru A; Aittomäki, Kristiina; Blomqvist, Carl; Schmidt, Marjanka K; Broeks, Annegien; Cornelissen, Sten; Hogervorst, Frans B L; Li, Jingmei; Brand, Judith S; Humphreys, Keith; Guénel, Pascal; Truong, Thérèse; Menegaux, Florence; Sanchez, Marie; Burwinkel, Barbara; Marmé, Frederik; Yang, Rongxi; Bugert, Peter; González-Neira, Anna; Benitez, Javier; Pilar Zamora, M; Arias Perez, Jose I; Cox, Angela; Cross, Simon S; Reed, Malcolm W R; Andrulis, Irene L; Knight, Julia A; Glendon, Gord; Tchatchou, Sandrine; Sawyer, Elinor J; Tomlinson, Ian; Kerin, Michael J; Miller, Nicola; Haiman, Christopher A; Schumacher, Fredrick; Henderson, Brian E; Le Marchand, Loic; Lindblom, Annika; Margolin, Sara; Hooning, Maartje J; Hollestelle, Antoinette; Kriege, Mieke; Koppert, Linetta B; Hopper, John L; Southey, Melissa C; Tsimiklis, Helen; Apicella, Carmel; Slettedahl, Seth; Toland, Amanda E; Vachon, Celine; Yannoukakos, Drakoulis; Giles, Graham G; Milne, Roger L; McLean, Catriona; Fasching, Peter A; Ruebner, Matthias; Ekici, Arif B; Beckmann, Matthias W; Brenner, Hermann; Dieffenbach, Aida K; Arndt, Volker; Stegmaier, Christa; Ashworth, Alan; Orr, Nicholas; Schoemaker, Minouk J; Swerdlow, Anthony; García-Closas, Montserrat; Figueroa, Jonine; Chanock, Stephen J; Lissowska, Jolanta; Goldberg, Mark S; Labrèche, France; Dumont, Martine; Winqvist, Robert; Pylkäs, Katri; Jukkola-Vuorinen, Arja; Grip, Mervi; Brauch, Hiltrud; Brüning, Thomas; Ko, Yon-Dschun; Radice, Paolo; Peterlongo, Paolo; Scuvera, Giulietta; Fortuzzi, Stefano; Bogdanova, Natalia; Dörk, Thilo; Mannermaa, Arto; Kataja, Vesa; Kosma, Veli-Matti; Hartikainen, Jaana M; Devilee, Peter; Tollenaar, Robert A E M; Seynaeve, Caroline; Van Asperen, Christi J; Jakubowska, Anna; Lubinski, Jan; Jaworska-Bieniek, Katarzyna; Durda, Katarzyna; Zheng, Wei; Shrubsole, Martha J; Cai, Qiuyin; Torres, Diana; Anton-Culver, Hoda; Kristensen, Vessela; Bacot, François; Tessier, Daniel C; Vincent, Daniel; Luccarini, Craig; Baynes, Caroline; Ahmed, Shahana; Maranian, Mel; Simard, Jacques; Chenevix-Trench, Georgia; Hall, Per; Pharoah, Paul D P; Dunning, Alison M; Easton, Douglas F; Hamann, Ute

    2015-02-01

    The chromosomal passenger complex (CPC) plays a pivotal role in the regulation of cell division. Therefore, inherited CPC variability could influence tumor development. The present candidate gene approach investigates the relationship between single nucleotide polymorphisms (SNPs) in genes encoding key CPC components and breast cancer risk. Fifteen SNPs in four CPC genes (INCENP, AURKB, BIRC5 and CDCA8) were genotyped in 88 911 European women from 39 case-control studies of the Breast Cancer Association Consortium. Possible associations were investigated in fixed-effects meta-analyses. The synonymous SNP rs1675126 in exon 7 of INCENP was associated with overall breast cancer risk [per A allele odds ratio (OR) 0.95, 95% confidence interval (CI) 0.92-0.98, P = 0.007] and particularly with estrogen receptor (ER)-negative breast tumors (per A allele OR 0.89, 95% CI 0.83-0.95, P = 0.0005). SNPs not directly genotyped were imputed based on 1000 Genomes. The SNPs rs1047739 in the 3' untranslated region and rs144045115 downstream of INCENP showed the strongest association signals for overall (per T allele OR 1.03, 95% CI 1.00-1.06, P = 0.0009) and ER-negative breast cancer risk (per A allele OR 1.06, 95% CI 1.02-1.10, P = 0.0002). Two genotyped SNPs in BIRC5 were associated with familial breast cancer risk (top SNP rs2071214: per G allele OR 1.12, 95% CI 1.04-1.21, P = 0.002). The data suggest that INCENP in the CPC pathway contributes to ER-negative breast cancer susceptibility in the European population. In spite of a modest contribution of CPC-inherited variants to the total burden of sporadic and familial breast cancer, their potential as novel targets for breast cancer treatment should be further investigated. PMID:25586992

  12. Inherited variants in the inner centromere protein (INCENP) gene of the chromosomal passenger complex contribute to the susceptibility of ER-negative breast cancer

    PubMed Central

    Kabisch, Maria; Lorenzo Bermejo, Justo; Dünnebier, Thomas; Ying, Shibo; Michailidou, Kyriaki; Bolla, Manjeet K.; Wang, Qin; Dennis, Joe; Shah, Mitul; Perkins, Barbara J.; Czene, Kamila; Darabi, Hatef; Eriksson, Mikael; Bojesen, Stig E.; Nordestgaard, Børge G.; Nielsen, Sune F.; Flyger, Henrik; Lambrechts, Diether; Neven, Patrick; Peeters, Stephanie; Weltens, Caroline; Couch, Fergus J.; Olson, Janet E.; Wang, Xianshu; Purrington, Kristen; Chang-Claude, Jenny; Rudolph, Anja; Seibold, Petra; Flesch-Janys, Dieter; Peto, Julian; dos-Santos-Silva, Isabel; Johnson, Nichola; Fletcher, Olivia; Nevanlinna, Heli; Muranen, Taru A.; Aittomäki, Kristiina; Blomqvist, Carl; Schmidt, Marjanka K.; Broeks, Annegien; Cornelissen, Sten; Hogervorst, Frans B.L.; Li, Jingmei; Brand, Judith S.; Humphreys, Keith; Guénel, Pascal; Truong, Thérèse; Menegaux, Florence; Sanchez, Marie; Burwinkel, Barbara; Marmé, Frederik; Yang, Rongxi; Bugert, Peter; González-Neira, Anna; Benitez, Javier; Pilar Zamora, M.; Arias Perez, Jose I.; Cox, Angela; Cross, Simon S.; Reed, Malcolm W.R.; Andrulis, Irene L.; Knight, Julia A.; Glendon, Gord; Tchatchou, Sandrine; Sawyer, Elinor J.; Tomlinson, Ian; Kerin, Michael J.; Miller, Nicola; Haiman, Christopher A.; Schumacher, Fredrick; Henderson, Brian E.; Le Marchand, Loic; Lindblom, Annika; Margolin, Sara; Hooning, Maartje J.; Hollestelle, Antoinette; Kriege, Mieke; Koppert, Linetta B.; Hopper, John L.; Southey, Melissa C.; Tsimiklis, Helen; Apicella, Carmel; Slettedahl, Seth; Toland, Amanda E.; Vachon, Celine; Yannoukakos, Drakoulis; Giles, Graham G.; Milne, Roger L.; McLean, Catriona; Fasching, Peter A.; Ruebner, Matthias; Ekici, Arif B.; Beckmann, Matthias W.; Brenner, Hermann; Dieffenbach, Aida K.; Arndt, Volker; Stegmaier, Christa; Ashworth, Alan; Orr, Nicholas; Schoemaker, Minouk J.; Swerdlow, Anthony; García-Closas, Montserrat; Figueroa, Jonine; Chanock, Stephen J.; Lissowska, Jolanta; Goldberg, Mark S.; Labrèche, France; Dumont, Martine; Winqvist, Robert; Pylkäs, Katri; Jukkola-Vuorinen, Arja; Grip, Mervi; Brauch, Hiltrud; Brüning, Thomas; Ko, Yon-Dschun; Radice, Paolo; Peterlongo, Paolo; Scuvera, Giulietta; Fortuzzi, Stefano; Bogdanova, Natalia; Dörk, Thilo; Mannermaa, Arto; Kataja, Vesa; Kosma, Veli-Matti; Hartikainen, Jaana M.; Devilee, Peter; Tollenaar, Robert A.E.M.; Seynaeve, Caroline; Van Asperen, Christi J.; Jakubowska, Anna; Lubinski, Jan; Jaworska-Bieniek, Katarzyna; Durda, Katarzyna; Zheng, Wei; Shrubsole, Martha J.; Cai, Qiuyin; Torres, Diana; Anton-Culver, Hoda; Kristensen, Vessela; Bacot, François; Tessier, Daniel C.; Vincent, Daniel; Luccarini, Craig; Baynes, Caroline; Ahmed, Shahana; Maranian, Mel; Simard, Jacques; Chenevix-Trench, Georgia; Hall, Per; Pharoah, Paul D.P.; Dunning, Alison M.; Easton, Douglas F.; Hamann, Ute

    2015-01-01

    The chromosomal passenger complex (CPC) plays a pivotal role in the regulation of cell division. Therefore, inherited CPC variability could influence tumor development. The present candidate gene approach investigates the relationship between single nucleotide polymorphisms (SNPs) in genes encoding key CPC components and breast cancer risk. Fifteen SNPs in four CPC genes (INCENP, AURKB, BIRC5 and CDCA8) were genotyped in 88 911 European women from 39 case-control studies of the Breast Cancer Association Consortium. Possible associations were investigated in fixed-effects meta-analyses. The synonymous SNP rs1675126 in exon 7 of INCENP was associated with overall breast cancer risk [per A allele odds ratio (OR) 0.95, 95% confidence interval (CI) 0.92–0.98, P = 0.007] and particularly with estrogen receptor (ER)-negative breast tumors (per A allele OR 0.89, 95% CI 0.83–0.95, P = 0.0005). SNPs not directly genotyped were imputed based on 1000 Genomes. The SNPs rs1047739 in the 3ʹ untranslated region and rs144045115 downstream of INCENP showed the strongest association signals for overall (per T allele OR 1.03, 95% CI 1.00–1.06, P = 0.0009) and ER-negative breast cancer risk (per A allele OR 1.06, 95% CI 1.02–1.10, P = 0.0002). Two genotyped SNPs in BIRC5 were associated with familial breast cancer risk (top SNP rs2071214: per G allele OR 1.12, 95% CI 1.04–1.21, P = 0.002). The data suggest that INCENP in the CPC pathway contributes to ER-negative breast cancer susceptibility in the European population. In spite of a modest contribution of CPC-inherited variants to the total burden of sporadic and familial breast cancer, their potential as novel targets for breast cancer treatment should be further investigated. PMID:25586992

  13. Dominating expression of negative regulatory factors downmodulates major histocompatibility complex Class-II expression on dendritic cells in chronic hepatitis C infection

    PubMed Central

    Tomer, Shallu; Chawla, Yogesh K; Duseja, Ajay; Arora, Sunil K

    2016-01-01

    AIM: To elucidate the molecular mechanisms leading to development of functionally impaired dendritic cells (DCs) in chronic hepatitis C (CHC) patients infected with genotype 3 virus. METHODS: This prospective study was conducted on the cohorts of CHC individuals identified as responders or non-responders to antiviral therapy. Myeloid DCs were isolated from the peripheral blood of each subject using CD1c (BDCA1)+ DC isolation Kit. Monocytes from healthy donor were cultured with DC growth factors such as IL-4 and GM-CSF either in the presence or absence of hepatitis C virus (HCV) viral proteins followed by LPS stimulation. Phenotyping was done by flowcytometry and gene expression profiling was evaluated by real-time PCR. RESULTS: Non-responders [sustained virological response (SVR)-ve] to conventional antiviral therapy had significantly higher expression of genes associated with interferon responsive element such as IDO1 and PD-L1 (6-fold) and negative regulators of JAK-STAT pathway such as SOCS (6-fold) as compared to responders (SVR+ve) to antiviral therapy. The down-regulated genes in non-responders included factors involved in antigen processing and presentation mainly belonging to major histocompatibility complex (MHC) Class-II family as HLA-DP, HLA-DQ (2-fold) and superoxide dismutase (2-fold). Cells grown in the presence of HCV viral proteins had genes down-regulated for factors involved in innate response, interferon signaling, DC maturation and co-stimulatory signaling to T-cells, while the genes for cytokine signaling and Toll-like receptors (4-fold) were up-regulated as compared to cells grown in absence of viral proteins. CONCLUSION: Underexpressed MHC class-II genes and upregulated negative regulators in non-responders indicate diminished capacity to present antigen and may constitute mechanism of functionally defective state of DCs. PMID:27298560

  14. High-throughput database search and large-scale negative polarity liquid chromatography-tandem mass spectrometry with ultraviolet photodissociation for complex proteomic samples.

    PubMed

    Madsen, James A; Xu, Hua; Robinson, Michelle R; Horton, Andrew P; Shaw, Jared B; Giles, David K; Kaoud, Tamer S; Dalby, Kevin N; Trent, M Stephen; Brodbelt, Jennifer S

    2013-09-01

    The use of ultraviolet photodissociation (UVPD) for the activation and dissociation of peptide anions is evaluated for broader coverage of the proteome. To facilitate interpretation and assignment of the resulting UVPD mass spectra of peptide anions, the MassMatrix database search algorithm was modified to allow automated analysis of negative polarity MS/MS spectra. The new UVPD algorithms were developed based on the MassMatrix database search engine by adding specific fragmentation pathways for UVPD. The new UVPD fragmentation pathways in MassMatrix were rigorously and statistically optimized using two large data sets with high mass accuracy and high mass resolution for both MS(1) and MS(2) data acquired on an Orbitrap mass spectrometer for complex Halobacterium and HeLa proteome samples. Negative mode UVPD led to the identification of 3663 and 2350 peptides for the Halo and HeLa tryptic digests, respectively, corresponding to 655 and 645 peptides that were unique when compared with electron transfer dissociation (ETD), higher energy collision-induced dissociation, and collision-induced dissociation results for the same digests analyzed in the positive mode. In sum, 805 and 619 proteins were identified via UVPD for the Halobacterium and HeLa samples, respectively, with 49 and 50 unique proteins identified in contrast to the more conventional MS/MS methods. The algorithm also features automated charge determination for low mass accuracy data, precursor filtering (including intact charge-reduced peaks), and the ability to combine both positive and negative MS/MS spectra into a single search, and it is freely open to the public. The accuracy and specificity of the MassMatrix UVPD search algorithm was also assessed for low resolution, low mass accuracy data on a linear ion trap. Analysis of a known mixture of three mitogen-activated kinases yielded similar sequence coverage percentages for UVPD of peptide anions versus conventional collision-induced dissociation of

  15. High-throughput Database Search and Large-scale Negative Polarity Liquid Chromatography–Tandem Mass Spectrometry with Ultraviolet Photodissociation for Complex Proteomic Samples*

    PubMed Central

    Madsen, James A.; Xu, Hua; Robinson, Michelle R.; Horton, Andrew P.; Shaw, Jared B.; Giles, David K.; Kaoud, Tamer S.; Dalby, Kevin N.; Trent, M. Stephen; Brodbelt, Jennifer S.

    2013-01-01

    The use of ultraviolet photodissociation (UVPD) for the activation and dissociation of peptide anions is evaluated for broader coverage of the proteome. To facilitate interpretation and assignment of the resulting UVPD mass spectra of peptide anions, the MassMatrix database search algorithm was modified to allow automated analysis of negative polarity MS/MS spectra. The new UVPD algorithms were developed based on the MassMatrix database search engine by adding specific fragmentation pathways for UVPD. The new UVPD fragmentation pathways in MassMatrix were rigorously and statistically optimized using two large data sets with high mass accuracy and high mass resolution for both MS1 and MS2 data acquired on an Orbitrap mass spectrometer for complex Halobacterium and HeLa proteome samples. Negative mode UVPD led to the identification of 3663 and 2350 peptides for the Halo and HeLa tryptic digests, respectively, corresponding to 655 and 645 peptides that were unique when compared with electron transfer dissociation (ETD), higher energy collision-induced dissociation, and collision-induced dissociation results for the same digests analyzed in the positive mode. In sum, 805 and 619 proteins were identified via UVPD for the Halobacterium and HeLa samples, respectively, with 49 and 50 unique proteins identified in contrast to the more conventional MS/MS methods. The algorithm also features automated charge determination for low mass accuracy data, precursor filtering (including intact charge-reduced peaks), and the ability to combine both positive and negative MS/MS spectra into a single search, and it is freely open to the public. The accuracy and specificity of the MassMatrix UVPD search algorithm was also assessed for low resolution, low mass accuracy data on a linear ion trap. Analysis of a known mixture of three mitogen-activated kinases yielded similar sequence coverage percentages for UVPD of peptide anions versus conventional collision-induced dissociation of

  16. Negative mass

    NASA Astrophysics Data System (ADS)

    Hammond, Richard T.

    2015-03-01

    Some physical aspects of negative mass are examined. Several unusual properties, such as the ability of negative mass to penetrate any armor, are analysed. Other surprising effects include the bizarre system of negative mass chasing positive mass, naked singularities and the violation of cosmic censorship, wormholes, and quantum mechanical results as well. In addition, a brief look into the implications for strings is given.

  17. On the structure of the two-stream instability-complex G-Hamiltonian structure and Krein collisions between positive- and negative-action modes

    NASA Astrophysics Data System (ADS)

    Zhang, Ruili; Qin, Hong; Davidson, Ronald C.; Liu, Jian; Xiao, Jianyuan

    2016-07-01

    The two-stream instability is probably the most important elementary example of collective instabilities in plasma physics and beam-plasma systems. For a warm plasma with two charged particle species, the instability diagram of the two-stream instability based on a 1D warm-fluid model exhibits an interesting band structure that has not been explained. We show that the band structure for this instability is the consequence of the Hamiltonian nature of the warm two-fluid system. Interestingly, the Hamiltonian nature manifests as a complex G-Hamiltonian structure in wave-number space, which directly determines the instability diagram. Specifically, it is shown that the boundaries between the stable and unstable regions are locations for Krein collisions between eigenmodes with different Krein signatures. In terms of physics, this rigorously implies that the system is destabilized when a positive-action mode resonates with a negative-action mode, and that this is the only mechanism by which the system can be destabilized. It is anticipated that this physical mechanism of destabilization is valid for other collective instabilities in conservative systems in plasma physics, accelerator physics, and fluid dynamics systems, which admit infinite-dimensional Hamiltonian structures.

  18. The Structure of the PanD/PanZ Protein Complex Reveals Negative Feedback Regulation of Pantothenate Biosynthesis by Coenzyme A

    PubMed Central

    Monteiro, Diana C.F.; Patel, Vijay; Bartlett, Christopher P.; Nozaki, Shingo; Grant, Thomas D.; Gowdy, James A.; Thompson, Gary S.; Kalverda, Arnout P.; Snell, Edward H.; Niki, Hironori; Pearson, Arwen R.; Webb, Michael E.

    2015-01-01

    Summary Coenzyme A (CoA) is an ubiquitous and essential cofactor, synthesized from the precursor pantothenate. Vitamin biosynthetic pathways are normally tightly regulated, including the pathway from pantothenate to CoA. However, no regulation of pantothenate biosynthesis has been identified. We have recently described an additional component in the pantothenate biosynthetic pathway, PanZ, which promotes the activation of the zymogen, PanD, to form aspartate α-decarboxylase (ADC) in a CoA-dependent manner. Here we report the structure of PanZ in complex with PanD, which reveals the structural basis for the CoA dependence of this interaction and activation. In addition, we show that PanZ acts as a CoA-dependent inhibitor of ADC catalysis. This inhibitory effect can effectively regulate the biosynthetic pathway to pantothenate, and thereby also regulate CoA biosynthesis. This represents a previously unobserved mode of metabolic regulation whereby a cofactor-utilizing protein negatively regulates the biosynthesis of the same cofactor. PMID:25910242

  19. HACE1 Negatively Regulates Virus-Triggered Type I IFN Signaling by Impeding the Formation of the MAVS-TRAF3 Complex.

    PubMed

    Mao, He-Ting; Wang, Yan; Cai, Juan; Meng, Jun-Ling; Zhou, Yu; Pan, Yu; Qian, Xiao-Ping; Zhang, Yu; Zhang, Jun

    2016-01-01

    During virus infection, the cascade signaling pathway that leads to the production of proinflammatory cytokines is controlled at multiple levels to avoid detrimental overreaction. HACE1 has been characterized as an important tumor suppressor. Here, we identified HACE1 as an important negative regulator of virus-triggered type I IFN signaling. Overexpression of HACE1 inhibited Sendai virus- or poly (I:C)-induced signaling and resulted in reduced IFNB1 production and enhanced virus replication. Knockdown of HACE1 expression exhibited the opposite effects. Ubiquitin E3 ligase activity of the dead mutant HACE1/C876A had a comparable inhibitory function as WT HACE1, suggesting that the suppressive function of HACE1 on virus-induced signaling is independent of its E3 ligase activity. Further study indicated that HACE1 acted downstream of MAVS and upstream of TBK1. Mechanistic studies showed that HACE1 exerts its inhibitory role on virus-induced signaling by disrupting the MAVS-TRAF3 complex. Therefore, we uncovered a novel function of HACE1 in innate immunity regulation. PMID:27213432

  20. The structure of the PanD/PanZ protein complex reveals negative feedback regulation of pantothenate biosynthesis by coenzyme A.

    PubMed

    Monteiro, Diana C F; Patel, Vijay; Bartlett, Christopher P; Nozaki, Shingo; Grant, Thomas D; Gowdy, James A; Thompson, Gary S; Kalverda, Arnout P; Snell, Edward H; Niki, Hironori; Pearson, Arwen R; Webb, Michael E

    2015-04-23

    Coenzyme A (CoA) is an ubiquitous and essential cofactor, synthesized from the precursor pantothenate. Vitamin biosynthetic pathways are normally tightly regulated, including the pathway from pantothenate to CoA. However, no regulation of pantothenate biosynthesis has been identified. We have recently described an additional component in the pantothenate biosynthetic pathway, PanZ, which promotes the activation of the zymogen, PanD, to form aspartate α-decarboxylase (ADC) in a CoA-dependent manner. Here we report the structure of PanZ in complex with PanD, which reveals the structural basis for the CoA dependence of this interaction and activation. In addition, we show that PanZ acts as a CoA-dependent inhibitor of ADC catalysis. This inhibitory effect can effectively regulate the biosynthetic pathway to pantothenate, and thereby also regulate CoA biosynthesis. This represents a previously unobserved mode of metabolic regulation whereby a cofactor-utilizing protein negatively regulates the biosynthesis of the same cofactor. PMID:25910242

  1. HACE1 Negatively Regulates Virus-Triggered Type I IFN Signaling by Impeding the Formation of the MAVS-TRAF3 Complex

    PubMed Central

    Mao, He-Ting; Wang, Yan; Cai, Juan; Meng, Jun-Ling; Zhou, Yu; Pan, Yu; Qian, Xiao-Ping; Zhang, Yu; Zhang, Jun

    2016-01-01

    During virus infection, the cascade signaling pathway that leads to the production of proinflammatory cytokines is controlled at multiple levels to avoid detrimental overreaction. HACE1 has been characterized as an important tumor suppressor. Here, we identified HACE1 as an important negative regulator of virus-triggered type I IFN signaling. Overexpression of HACE1 inhibited Sendai virus- or poly (I:C)-induced signaling and resulted in reduced IFNB1 production and enhanced virus replication. Knockdown of HACE1 expression exhibited the opposite effects. Ubiquitin E3 ligase activity of the dead mutant HACE1/C876A had a comparable inhibitory function as WT HACE1, suggesting that the suppressive function of HACE1 on virus-induced signaling is independent of its E3 ligase activity. Further study indicated that HACE1 acted downstream of MAVS and upstream of TBK1. Mechanistic studies showed that HACE1 exerts its inhibitory role on virus-induced signaling by disrupting the MAVS-TRAF3 complex. Therefore, we uncovered a novel function of HACE1 in innate immunity regulation. PMID:27213432

  2. Negative Regulation of p21Waf1/Cip1 by Human INO80 Chromatin Remodeling Complex Is Implicated in Cell Cycle Phase G2/M Arrest and Abnormal Chromosome Stability

    PubMed Central

    Cao, Lingling; Ding, Jian; Dong, Liguo; Zhao, Jiayao; Su, Jiaming; Wang, Lingyao; Sui, Yi; Zhao, Tong; Wang, Fei; Jin, Jingji; Cai, Yong

    2015-01-01

    We previously identified an ATP-dependent human Ino80 (INO80) chromatin remodeling complex which shares a set of core subunits with yeast Ino80 complex. Although research evidence has suggested that INO80 complex functions in gene transcription and genome stability, the precise mechanism remains unclear. Herein, based on gene expression profiles from the INO80 complex-knockdown in HeLa cells, we first demonstrate that INO80 complex negatively regulates the p21Waf1/Cip1 (p21) expression in a p53-mediated mechanism. In chromatin immunoprecipitation (ChIP) and a sequential ChIP (Re-ChIP) assays, we determined that the INO80 complex and p53 can bind to the same promoter region of p21 gene (-2.2kb and -1.0kb upstream of the p21 promoter region), and p53 is required for the recruitment of the INO80 complex to the p21 promoter. RNAi knockdown strategies of INO80 not only led to prolonged progression of cell cycle phase G2/M to G1, but it also resulted in abnormal chromosome stability. Interestingly, high expression of p21 was observed in most morphologically-changed cells, suggesting that negative regulation of p21 by INO80 complex might be implicated in maintaining the cell cycle process and chromosome stability. Together, our findings will provide a theoretical basis to further elucidate the cellular mechanisms of the INO80 complex. PMID:26340092

  3. Exploring the complexities of body image experiences in middle age and older adult women within an exercise context: The simultaneous existence of negative and positive body images.

    PubMed

    Bailey, K Alysse; Cline, Lindsay E; Gammage, Kimberley L

    2016-06-01

    Despite many body changes that accompany the aging process, the extant research is limited on middle age and older adults' body image experiences. The purpose of the present study was to explore how body image is represented for middle age and older adult women. Using thematic analysis, 10 women over the age of 55 were interviewed within an exercise context. The following themes were found: body dissatisfaction, body satisfaction despite ageist stereotypes, neutral body image within cohort, and positive body image characteristics. Negative and positive body images were experienced simultaneously, with neutral experiences expressed as low levels of dissatisfaction. This supports the contention that negative and positive body images exist on separate continuums and neutral body image is likely on the same continuum as negative body image. Programs that foster a social support network to reduce negative body image and improve positive body image in older female populations are needed. PMID:26989980

  4. Effect of Polyelectrolyte Stiffness and Solution pH on the Nanostructure of Complexes Formed by Cationic Amphiphiles and Negatively Charged Polyelectrolytes.

    PubMed

    Ram-On, Maor; Cohen, Yachin; Talmon, Yeshayahu

    2016-07-01

    The interaction between amphiphiles and polyelectrolytes has been widely investigated in recent years due to their potential application in industry and medicine, with special focus on gene therapy. The cationic lipid dioleoyl trimethylammonium propane, DOTAP, and the oppositely charged polyelectrolytes, sodium poly(acrylic acid) and sodium poly(styrenesulfonate), form multilamellar complexes in water. Because of the different molecular stiffness of the two polyelectrolytes, they form different nanostructured complexes. Also, because of the different ionization behavior of the two polyelectrolytes, pH differently affects the complexation of the polyelectrolytes with didodecyldimethylammonium bromide (DDAB), another cationic surfactant. We used cryogenic temperature transmission electron microscopy (cryo-TEM) and small-angle X-ray scattering (SAXS) to compare the nanostructures formed. Our results show that although the basic nanostructures of the complexes are always lamellar (multilamellar or unilamellar) the morphology of the complexes is affected by the polyelectrolyte rigidity and the solution pH. PMID:27049758

  5. Mutations within the LINC-HELLP non-coding RNA differentially bind ribosomal and RNA splicing complexes and negatively affect trophoblast differentiation.

    PubMed

    van Dijk, Marie; Visser, Allerdien; Buabeng, Kwadwo M L; Poutsma, Ankie; van der Schors, Roel C; Oudejans, Cees B M

    2015-10-01

    LINC-HELLP, showing chromosomal linkage with the pregnancy-specific HELLP syndrome in Dutch families, reduces differentiation from a proliferative to an invasive phenotype of first-trimester extravillous trophoblasts. Here we show that mutations in LINC-HELLP identified in HELLP families negatively affect this trophoblast differentiation either by inducing proliferation rate or by causing cell cycle exit as shown by a decrease in both proliferation and invasion. As LincRNAs predominantly function through interactions with proteins, we identified the directly interacting proteins using chromatin isolation by RNA purification followed by protein mass spectrometry. We found 22 proteins predominantly clustering in two functional networks, i.e. RNA splicing and the ribosome. YBX1, PCBP1, PCBP2, RPS6 and RPL7 were validated, and binding to these proteins was influenced by the HELLP mutations carried. Finally, we show that the LINC-HELLP transcript levels are significantly upregulated in plasma of women in their first trimester of pregnancy compared with non-pregnant women, whereas this upregulation seems absent in a pilot set of patients later developing pregnancy complications, indicative of its functional significance in vivo. PMID:26173455

  6. IS1311 and IS1245 Restriction Fragment Length Polymorphism Analyses, Serotypes, and Drug Susceptibilities of Mycobacterium avium Complex Isolates Obtained from a Human Immunodeficiency Virus-Negative Patient

    PubMed Central

    Dvorska, Lenka; Bartos, Milan; Ostadal, Oldrich; Kaustova, Jarmila; Matlova, Ludmila; Pavlik, Ivo

    2002-01-01

    Six isolates of Mycobacterium avium of genotype dnaJ+ IS901− IS1311+ IS1245+ and serotypes 6 (n = 1), 6/9, (n = 2), and 9 (n = 3) were obtained within a 5-month period from a human immunodeficiency virus-negative patient treated for tuberculosis. The isolates were identified with PvuII restriction fragment length polymorphism (RFLP) analysis as a single IS1311 RFLP type and six different IS1245 RFLP types. Six separate colonies/clones obtained by subculture from each of the six isolates were tested for MICs of a set of 10 drugs. This report documents the appearance of isolates that are resistant to antimycobacterial drugs as the duration of therapy increases. Because isolates recovered from the patient following longer duration of treatment were more likely to be resistant to more antimycobacterial drugs, we would conclude that there was selection for antimycobacterial drug-resistant isolates. Analyses of all 36 clones identified three IS1311 and 22 IS1245 types forming three clusters. Tests of 105 environmental samples collected in the home and the work place of the patient yielded 16 mycobacterial isolates, of which one M. avium from soil was of genotype dnaJ+ IS901+ IS1311+ IS1245+ and serotype 2, and the second M. avium from a vacuum cleaner was of genotype dnaJ+ IS901− IS1311+ IS1245+ and serotype 9. Overall analyses of the results did not reveal any relation between serotype, RFLP type, and drug susceptibility. Based on the course of the disease in the patient and different serotypes, IS1311 and IS1245 RFLP types of isolates of M. avium we suppose represent polyclonal infection. PMID:12354870

  7. Macroporous hydrogels based on 2-hydroxyethyl methacrylate. Part 4: growth of rat bone marrow stromal cells in three-dimensional hydrogels with positive and negative surface charges and in polyelectrolyte complexes.

    PubMed

    Lesný, P; Prádný, M; Jendelová, P; Michálek, J; Vacík, J; Syková, E

    2006-09-01

    The growth of bone marrow stromal cells was assessed in vitro in macroporous hydrogels based on 2-hydro- xyethyl methacrylate (HEMA) copolymers with different electric charges. Copolymers of HEMA with sodium methacrylate (MA(-)) carried a negative electric charge, copolymers of HEMA with [2-(methacryloyloxy)ethyl] trimethylammonium chloride (MOETA(-)) carried a positive electric charge and terpolymers of HEMA, MA(-) and MOETA(+) carried both, positive and negative electric charges. The charges in the polyelectrolyte complexes were shielded by counter-ions. The hydrogels had similar porosities, based on a comparison of their diffusion parameters for small cations as measured by the real-time tetramethylammonium iontophoretic method of diffusion analysis. The cell growth was studied in the peripheral and central regions of the hydrogels at 2 hours and 2, 7, 14 and 28 days after cell seeding. Image analysis revealed the highest cellular density in the HEMA-MOETA(+) copolymers; most of the cells were present in the peripheral region of the hydrogels. A lower density of cells but no difference between the peripheral and central regions was observed in the HEMA-MA(-) copolymers and in polyelectrolyte complexes. This study showed that positively charged functional groups promote the adhesion of cells. PMID:16932865

  8. ARS5 is a component of the 26S proteasome complex, and negatively regulates thiol biosynthesis and arsenic tolerance in Arabidopsis.

    PubMed

    Sung, Dong-Yul; Kim, Tae-Houn; Komives, Elizabeth A; Mendoza-Cózatl, David G; Schroeder, Julian I

    2009-09-01

    A forward-genetic screen in Arabidopsis led to the isolation of several arsenic tolerance mutants. ars5 was the strongest arsenate- and arsenite-resistant mutant identified in this genetic screen. Here, we report the characterization and cloning of the ars5 mutant gene. ars5 is shown to exhibit an increased accumulation of arsenic and thiol compounds during arsenic stress. Rough mapping together with microarray-based expression mapping identified the ars5 mutation in the alpha subunit F (PAF1) of the 26S proteasome complex. Characterization of an independent paf1 T-DNA insertion allele and complementation by PAF1 confirmed that paf1 mutation is responsible for the enhanced thiol accumulation and arsenic tolerance phenotypes. Arsenic tolerance was not observed in a knock-out mutant of the highly homologous PAF2 gene. However, genetic complementation of ars5 by the overexpression of PAF2 suggests that the PAF2 protein is functionally equivalent to PAF1 when expressed at high levels. No detectible difference was observed in total ubiquitinylated protein profiles between ars5 and wild-type (WT) Arabidopsis, suggesting that the arsenic tolerance observed in ars5 is not derived from a general impairment in proteasome-mediated protein degradation. Quantitative RT-PCR showed that arsenic induces the enhanced transcriptional activation of several key genes that function in glutathione and phytochelatin biosynthesis in the WT, and this arsenic induction of gene expression is more dramatic in ars5. The enhanced transcriptional response to arsenic and the increased accumulation of thiol compounds in ars5, compared with WT, suggest the presence of a positive regulation pathway for thiol biosynthesis that is enhanced in the ars5 background. PMID:19453443

  9. ARS5 is a component of the 26S proteasome complex and negatively regulates thiol biosynthesis and arsenic tolerance in Arabidopsis

    PubMed Central

    Sung, Dong-Yul; Kim, Tae-Houn; Komives, Elizabeth A.; Mendoza-Cózatl, David G.; Schroeder, Julian I.

    2010-01-01

    Summary A forward genetic screen in Arabidopsis led to the isolation of several arsenic tolerance mutants. ars5 is the strongest arsenate and arsenite resistant mutant identified in this genetic screen. Here, we report the characterization and cloning of the ars5 mutant gene. ars5 is shown to exhibit an increased accumulation of arsenic and thiol compounds during arsenic stress. Rough mapping together with microarray-based expression mapping identified the ars5 mutation in the alpha subunit F (PAF1) of the 26S proteasome complex. Characterization of an independent paf1 T-DNA insertion allele and complementation by PAF1 confirmed that paf1 mutation is responsible for the enhanced thiol accumulation and the arsenic tolerance phenotypes. Arsenic tolerance was not observed in a knockout mutant of the highly homologous PAF2 gene. However, genetic complementation of ars5 by over expression of PAF2 suggests that the PAF2 protein is functionally equivalent to PAF1 when expressed at high levels. No detectible difference was observed in total ubiquitinylated protein profiles between ars5 and wild type Arabidopsis, suggesting that the arsenic tolerance observed in ars5 is not derived from a general impairment in proteasome-mediated protein degradation. Quantitative RT-PCR showed that arsenic induces enhanced transcriptional activation of several key genes that function in glutathione and phytochelatin biosynthesis in wild type and this arsenic-induction of gene expression is more dramatic in ars5. The enhanced transcriptional response to arsenic and the increased accumulation of thiol compounds in ars5 compared to WT suggest the presence of a positive regulation pathway for thiol biosynthesis that is enhanced in the ars5 background. PMID:19453443

  10. The SWI/SNF chromatin remodeling complex exerts both negative and positive control over LET-23/EGFR-dependent vulval induction in Caenorhabditis elegans.

    PubMed

    Flibotte, Stephane; Kim, Bo Ram; Van de Laar, Emily; Brown, Louise; Moghal, Nadeem

    2016-07-01

    Signaling by the epidermal growth factor receptor (EGFR) generates diverse developmental patterns. This requires precise control over the location and intensity of signaling. Elucidation of these regulatory mechanisms is important for understanding development and disease pathogenesis. In Caenorhabditis elegans, LIN-3/EGF induces vulval formation in the mid-body, which requires LET-23/EGFR activation only in P6.p, the vulval progenitor nearest the LIN-3 source. To identify mechanisms regulating this signaling pattern, we screened for mutations that cooperate with a let-23 gain-of-function allele to cause ectopic vulval induction. Here, we describe a dominant gain-of-function mutation in swsn-4, a component of SWI/SNF chromatin remodeling complexes. Loss-of-function mutations in multiple SWI/SNF components reveal that weak reduction in SWI/SNF activity causes ectopic vulval induction, while stronger reduction prevents adoption of vulval fates, a phenomenon also observed with increasing loss of LET-23 activity. High levels of LET-23 expression in P6.p are thought to locally sequester LIN-3, thereby preventing ectopic vulval induction, with slight reductions in its expression interfering with LIN-3 sequestration, but not vulval fate signaling. We find that SWI/SNF positively regulates LET-23 expression in P6.p descendants, providing an explanation for the similarities between let-23 and SWI/SNF mutant phenotypes. However, SWI/SNF regulation of LET-23 expression is cell-specific, with SWI/SNF repressing its expression in the ALA neuron. The swsn-4 gain-of-function mutation affects the PTH domain, and provides the first evidence that its auto-inhibitory function in yeast Sth1p is conserved in metazoan chromatin remodelers. Finally, our work supports broad use of SWI/SNF in regulating EGFR signaling during development, and suggests that dominant SWI/SNF mutations in certain human congenital anomaly syndromes may be gain-of-functions. PMID:27207389

  11. Identification of phosphorylated peptides from complex mixtures using negative-ion orifice-potential stepping and capillary liquid chromatography/electrospray ionization mass spectrometry.

    PubMed

    Ding, J; Burkhart, W; Kassel, D B

    1994-01-01

    A rapid method for identifying and characterizing sites of phosphorylation of peptides and proteins is described. High-performance capillary liquid chromatography (HPLC) coupled with electrospray ionization mass spectrometry (ESI-MS) is used to distinguish non-phosphorylated and phosphorylated peptides originating from mixtures as complex as enzyme digests. The method relies on the ability to produce a fragment ion characteristic and unique to phosphopeptides (m/z 79, PO3) by stepping the orifice potential of the mass spectrometer as a function of mass. At low m/z values, a high orifice potential is applied to induce extensive fragmentation of the peptide, leading to the formation of the m/z 79 phosphate-derived ion. This method is analogous to that described by Carr et al. for the identification of glycopeptides from enzymatic digestion of glycoproteins (S.A. Carr, M.J. Huddleston, M.F. Bean, Protein Science 2, 183 (1993)). The method was first evaluated and validated for a mixture of non-, mono- and di-phosphorylated synthetic peptides. Both mono- and di-phosphorylated peptides were found to generate fragment ions characteristic of PO3 whereas the non-phosphorylated peptide did not. Application of the method was extended to identifying phosphopeptides generated from an endoprotease Lys-C digestion of beta-casein. Both the expected mono- and tetra-phosphorylated Lys-C peptides were observed and identified rapidly in the LC/SEI-MS analysis. The procedure was used additionally to identify the site(s) of phosphorylation of the cytosolic non-receptor tyrosine kinase, pp60(c-src). PMID:8118063

  12. Neurobiological background of negative symptoms.

    PubMed

    Galderisi, Silvana; Merlotti, Eleonora; Mucci, Armida

    2015-10-01

    Studies investigating neurobiological bases of negative symptoms of schizophrenia failed to provide consistent findings, possibly due to the heterogeneity of this psychopathological construct. We tried to review the findings published to date investigating neurobiological abnormalities after reducing the heterogeneity of the negative symptoms construct. The literature in electronic databases as well as citations and major articles are reviewed with respect to the phenomenology, pathology, genetics and neurobiology of schizophrenia. We searched PubMed with the keywords "negative symptoms," "deficit schizophrenia," "persistent negative symptoms," "neurotransmissions," "neuroimaging" and "genetic." Additional articles were identified by manually checking the reference lists of the relevant publications. Publications in English were considered, and unpublished studies, conference abstracts and poster presentations were not included. Structural and functional imaging studies addressed the issue of neurobiological background of negative symptoms from several perspectives (considering them as a unitary construct, focusing on primary and/or persistent negative symptoms and, more recently, clustering them into factors), but produced discrepant findings. The examined studies provided evidence suggesting that even primary and persistent negative symptoms include different psychopathological constructs, probably reflecting the dysfunction of different neurobiological substrates. Furthermore, they suggest that complex alterations in multiple neurotransmitter systems and genetic variants might influence the expression of negative symptoms in schizophrenia. On the whole, the reviewed findings, representing the distillation of a large body of disparate data, suggest that further deconstruction of negative symptomatology into more elementary components is needed to gain insight into underlying neurobiological mechanisms. PMID:25797499

  13. Meningitis - gram-negative

    MedlinePlus

    Gram-negative meningitis ... Acute bacterial meningitis can be caused by Gram-negative bacteria. Meningococcal and H. influenzae meningitis are caused by Gram-negative bacteria and are covered in detail in other articles. This article ...

  14. [Negative symptoms and cerebral imaging].

    PubMed

    Kaladjian, A; Belzeaux, R; Adida, M; Azorin, J-M

    2015-12-01

    A number of neuroanatomical and neurofonctional abnormalities have been evidenced by cerebral imaging studies in patients suffering from schizophrenia. Nevertheless, those specifically associated with the negative symptoms of this disease are still insufficiently known. This work is a review of selected studies that have assessed the brain correlates of negative symptoms in schizophrenia. Approaches using structural imaging have highlighted reduction of gray matter density or cortical thickness associated with negative symptoms, which is rather sparsely distributed within the frontal and temporal regions, localized nevertheless more particularly in the frontal medial and orbitofrontal areas, as well as the amygdalo-hippocampic complex. These deficits are concurrent with a loss of integrity of the principal paths of white matter tracts between frontal and limbic regions. On the other hand, neurofonctional abnormalities associated with negative symptoms involve especially the frontal areas and limbic striatum. A disturbed functioning within the fronto-striatal loops, related to a striatal dopaminergic deficit, may represent a potential explanatory hypothesis of the negative symptoms of schizophrenia, as suggested by studies using Positron Emission Tomography on this topic or neuroimaging studies on the effects of antipsychotics. A better identification of the cerebral abnormalities associated with the negative dimension of schizophrenia, with regard to the lateralization of these abnormalities or to their changes during the course of the disease, could offer new therapeutic modalities for the treatment of this dimension which, until now, remains few responsive to conventional pharmacological treatments. PMID:26776387

  15. The miRNA miR-34a enhances HIV-1 replication by targeting PNUTS/PPP1R10, which negatively regulates HIV-1 transcriptional complex formation.

    PubMed

    Kapoor, Richa; Arora, Sakshi; Ponia, Sanket S; Kumar, Binod; Maddika, Subbareddy; Banerjea, Akhil C

    2015-09-15

    HIV-1 relies heavily on the host cellular machinery for its replication. During infection, HIV-1 is known to modulate the host-cell miRNA profile. One of the miRNAs, miR-34a, is up-regulated by HIV-1 in T-cells as suggested by miRNA microarray studies. However, the functional consequences and the mechanism behind this phenomenon were not explored. The present study shows that HIV-1 enhances miR-34a in a time-dependent manner in T-cells. Our overexpression and knockdown-based experimental results suggest that miR-34a promotes HIV-1 replication in T-cells. Hence, there is a positive feedback loop between miR-34a and HIV-1 replication. We show that the mechanism of action of miR-34a in HIV-1 replication involves a cellular protein, the phosphatase 1 nuclear-targeting subunit (PNUTS). PNUTS expression levels decrease with the progression of HIV-1 infection in T-cells. Also, the overexpression of PNUTS potently inhibits HIV-1 replication in a dose-dependent manner. We report for the first time that PNUTS negatively regulates HIV-1 transcription by inhibiting the assembly of core components of the transcription elongation factor P-TEFb, i.e. cyclin T1 and CDK9. Thus, HIV-1 increases miR-34a expression in cells to overcome the inhibitory effect of PNUTS on HIV-1 transcription. So, the present study provides new mechanistic details with regard to our understanding of a complex interplay between miR-34a and the HIV-1 transcription machinery involving PNUTS. PMID:26188041

  16. Protein Kinase C-Mediated Phosphorylation of BCL11B at Serine 2 Negatively Regulates Its Interaction with NuRD Complexes during CD4+ T-Cell Activation.

    PubMed

    Dubuissez, Marion; Loison, Ingrid; Paget, Sonia; Vorng, Han; Ait-Yahia, Saliha; Rohr, Olivier; Tsicopoulos, Anne; Leprince, Dominique

    2016-07-01

    The transcription factor BCL11B/CTIP2 is a major regulatory protein implicated in various aspects of development, function and survival of T cells. Mitogen-activated protein kinase (MAPK)-mediated phosphorylation and SUMOylation modulate BCL11B transcriptional activity, switching it from a repressor in naive murine thymocytes to a transcriptional activator in activated thymocytes. Here, we show that BCL11B interacts via its conserved N-terminal MSRRKQ motif with endogenous MTA1 and MTA3 proteins to recruit various NuRD complexes. Furthermore, we demonstrate that protein kinase C (PKC)-mediated phosphorylation of BCL11B Ser2 does not significantly impact BCL11B SUMOylation but negatively regulates NuRD recruitment by dampening the interaction with MTA1 or MTA3 (MTA1/3) and RbAp46 proteins. We detected increased phosphorylation of BCL11B Ser2 upon in vivo activation of transformed and primary human CD4(+) T cells. We show that following activation of CD4(+) T cells, BCL11B still binds to IL-2 and Id2 promoters but activates their transcription by recruiting P300 instead of MTA1. Prolonged stimulation results in the direct transcriptional repression of BCL11B by KLF4. Our results unveil Ser2 phosphorylation as a new BCL11B posttranslational modification linking PKC signaling pathway to T-cell receptor (TCR) activation and define a simple model for the functional switch of BCL11B from a transcriptional repressor to an activator during TCR activation of human CD4(+) T cells. PMID:27161321

  17. Negative-ion states

    SciTech Connect

    Compton, R.N.

    1982-01-01

    In this brief review, we discuss some of the properties of atomic and molecular negative ions and their excited states. Experiments involving photon reactions with negative ions and polar dissociation are summarized. 116 references, 14 figures.

  18. Negative ion generator

    DOEpatents

    Stinnett, R.W.

    1984-05-08

    A negative ion generator is formed from a magnetically insulated transmission line having a coating of graphite on the cathode for producing negative ions and a plurality of apertures on the opposed anode for the release of negative ions. Magnetic insulation keeps electrons from flowing from the cathode to the anode. A transverse magnetic field removes electrons which do escape through the apertures from the trajectory of the negative ions. 8 figs.

  19. Negative ion generator

    DOEpatents

    Stinnett, Regan W.

    1984-01-01

    A negative ion generator is formed from a magnetically insulated transmission line having a coating of graphite on the cathode for producing negative ions and a plurality of apertures on the opposed anode for the release of negative ions. Magnetic insulation keeps electrons from flowing from the cathode to the anode. A transverse magnetic field removes electrons which do escape through the apertures from the trajectory of the negative ions.

  20. [Negative symptoms: which antipsychotics?].

    PubMed

    Maurel, M; Belzeaux, R; Adida, M; Azorin, J-M

    2015-12-01

    Treating negative symptoms of schizophrenia is a major issue and a challenge for the functional and social prognosis of the disease, to which they are closely linked. First- and second-generation antipsychotics allow a reduction of all negative symptoms. The hope of acting directly on primary negative symptoms with any antipsychotic is not supported by the literature. However, the effectiveness of first- and second-generation antipsychotics is demonstrated on secondary negative symptoms. PMID:26776390

  1. Sentential Negation in English

    ERIC Educational Resources Information Center

    Mowarin, Macaulay

    2009-01-01

    This paper undertakes a detailed analysis of sentential negation in the English language with Chomsky's Government-Binding theory of Transformational Grammar as theoretical model. It distinguishes between constituent and sentential negation in English. The essay identifies the exact position of Negation phrase in an English clause structure. It…

  2. The Syntax of Negation in English and Japanese

    ERIC Educational Resources Information Center

    Fujita, Takemasa

    1975-01-01

    The distribution and form of negatives in Japanese as compared to English in the simple declarative sentence, in the interrogative sentence, in different speech styles, in indefinite negatives, and in complex sentences. (SC)

  3. Negative Ion Density Fronts

    SciTech Connect

    Igor Kaganovich

    2000-12-18

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas.

  4. The addiction to negativity.

    PubMed

    Lane, R C; Hull, J W; Foehrenbach, L M

    1991-01-01

    In this paper, we have described a type of resistance that has attracted increasing psychoanalytic attention in recent years. Patients exposed to intense negativity during early life may develop an addiction to negative experience as adolescents and adults, and this may constitute a central organizing feature of their personality. In almost all patients, however, some moments of negativity may be observed. We have traced the developmental origins of an attachment to negativity, drawing especially on psychoanalytic investigations of preoedipal pathology. Manifestations and derivatives of early negativity include anhedonia, attachment to physical pain, fear of success, masochism, deprivation of self and others, and negative voyeurism. In discussing the dynamic functions of negativity, we place particular emphasis on two motives: the patient's desires for revenge against early objects that have been a source of deprivation and frustration; and the defensive function of negativity in helping to express as well as ward off dangerous wishes to merge with the object. Deviant forms of autoerotism are likely to be used by these patients to deal with the reactivation of early experiences of neglect and rejection. When negativity is used as a defense or method of relating to others it can lead to a severe disruption of the psychotherapeutic relationship. We have reviewed suggestions for the management of extreme negativity in treatment. Resolution of the therapist's countertransference reactions, especially induced feelings of frustration, rage, and helplessness, is crucial. Emphasis also has been placed on the patient's desires for revenge against self and object, and the manner in which these may be understood and eventually resolved. Only when patient and therapist begin to investigate the adaptive functions of extreme negativity can this pathological symptom be resolved and the patient's awareness of self and sense of autonomy be enhanced. PMID:1763149

  5. The Evolution of Negation.

    ERIC Educational Resources Information Center

    Croft, William

    1991-01-01

    Discusses a method for extrapolation of diachronic processes from synchronic states, the dynamicization of synchronic typologies, to propose a hitherto unobserved historical source for markers of verbal negation, namely irregular negative existential predicate forms. Explanations are proposed for the occurrence of the attested processes in this…

  6. Learning from Negative Morality.

    ERIC Educational Resources Information Center

    Oser, Fritz K.

    1996-01-01

    Identifies and discusses the elements and applications of learning from negative morality. Negative morality refers to the experience of learning from mistakes thereby creating a body of personal knowledge about "what not to do." This knowledge not only protects individuals but steers them to the right behavior. (MJP)

  7. On Negative Mass

    NASA Astrophysics Data System (ADS)

    Belletête, Jonathan; Paranjape, M. B.

    2013-06-01

    The Schwarzschild solution to the matter free, spherically symmetric Einstein equations has one free parameter, the mass. But the mass can be of any sign. What is the meaning of the negative mass solutions? The answer to this question for the case of a pure Schwarzschild negative mass black solution is still elusive, however, in this essay, we will consider negative mass solutions within a Schwarzschild-de Sitter geometry. We show that there exist reasonable configurations of matter, bubbles of distributions of matter, that satisfy the dominant energy condition everywhere, that are nonsingular and well behaved everywhere, but correspond to the negative mass Schwarzschild-de Sitter geometry outside the matter distribution. These negative mass bubbles could occur as the end state of a quantum tunneling transition.

  8. Kriging without negative weights

    SciTech Connect

    Szidarovszky, F.; Baafi, E.Y.; Kim, Y.C.

    1987-08-01

    Under a constant drift, the linear kriging estimator is considered as a weighted average of n available sample values. Kriging weights are determined such that the estimator is unbiased and optimal. To meet these requirements, negative kriging weights are sometimes found. Use of negative weights can produce negative block grades, which makes no practical sense. In some applications, all kriging weights may be required to be nonnegative. In this paper, a derivation of a set of nonlinear equations with the nonnegative constraint is presented. A numerical algorithm also is developed for the solution of the new set of kriging equations.

  9. Negative birefringent polyimide films

    NASA Technical Reports Server (NTRS)

    Harris, Frank W. (Inventor); Cheng, Stephen Z. D. (Inventor)

    1994-01-01

    A negative birefringent film, useful in liquid crystal displays, and a method for controlling the negative birefringence of a polyimide film is disclosed which allows the matching of an application to a targeted amount of birefringence by controlling the degree of in-plane orientation of the polyimide by the selection of functional groups within both the diamine and dianhydride segments of the polyimide which affect the polyimide backbone chain rigidity, linearity, and symmetry. The higher the rigidity, linearity and symmetry of the polyimide backbone, the larger the value of the negative birefringence of the polyimide film.

  10. The negative relief of large river floodplains

    NASA Astrophysics Data System (ADS)

    Lewin, John; Ashworth, Philip J.

    2014-02-01

    Large floodplains have multiple and complex negative relief assemblages in which depressions fall below local or general floodplain surfaces at a variety of scales. The generation and dynamics of negative relief along major alluvial corridors are described and compared. Such depressions are significant for the storage and passage of surface waters, the creation of a range of riparian, wetland, lacustrine and flowing-water habitats, and the long-term accumulation of organic materials.

  11. Negative electrode composition

    DOEpatents

    Kaun, Thomas D.; Chilenskas, Albert A.

    1982-01-01

    A secondary electrochemical cell and a negative electrode composition for use therewith comprising a positive electrode containing an active material of a chalcogen or a transiton metal chalcogenide, a negative electrode containing a lithium-aluminum alloy and an amount of a ternary alloy sufficient to provide at least about 5 percent overcharge capacity relative to a negative electrode solely of the lithium-aluminum alloy, the ternary alloy comprising lithium, aluminum, and iron or cobalt, and an electrolyte containing lithium ions in contact with both of the positive and the negative electrodes. The ternary alloy is present in the electrode in the range of from about 5 percent to about 50 percent by weight of the electrode composition and may include lithium-aluminum-nickel alloy in combination with either the ternary iron or cobalt alloys. A plurality of series connected cells having overcharge capacity can be equalized on the discharge side without expensive electrical equipment.

  12. Logo and Negative Numbers.

    ERIC Educational Resources Information Center

    Strawn, Candace A.

    1998-01-01

    Describes LOGO's turtle graphics capabilities based on a sixth-grade classroom's activities with negative numbers and Logo programming. A sidebar explains LOGO and offers suggestions to teachers for using LOGO effectively. (LRW)

  13. Atomic negative ions

    SciTech Connect

    Brage, T.

    1991-01-01

    We review some of the recent progress in the studies of alkaline-earth, negative ions. Computations of autodetachment rates, electron affinities and transition wavelengths are discussed and some new and improved results are given.

  14. Atomic negative ions

    SciTech Connect

    Brage, T.

    1991-12-31

    We review some of the recent progress in the studies of alkaline-earth, negative ions. Computations of autodetachment rates, electron affinities and transition wavelengths are discussed and some new and improved results are given.

  15. Negative affixes in medical English.

    PubMed

    Dzuganova, B

    2006-01-01

    Many medical terms have negative meaning expressed by means of a negative prefix or suffix. The most frequently used negative prefixes are: a-, dis-, in-, non-, and un-. There is only one negative suffix -less (Ref. 15). PMID:17125069

  16. Context, engagement, and the (multiple) functions of negativity bias.

    PubMed

    Federico, Christopher M; Johnston, Christopher D; Lavine, Howard G

    2014-06-01

    Hibbing and colleagues argue that political attitudes may be rooted in individual differences in negativity bias. Here, we highlight the complex, conditional nature of the relationship between negativity bias and ideology by arguing that the political impact of negativity bias should vary as a function of (1) issue domain and (2) political engagement. PMID:24970433

  17. Negative pressure wound therapy.

    PubMed

    Thompson, James T; Marks, Malcolm W

    2007-10-01

    Negative pressure wound therapy has become an increasingly important part of wound management. Over the last decade, numerous uses for this method of wound management have been reported, ranging from acute and chronic wounds, to closure of open sternal and abdominal wounds, to assistance with skin grafts. The biophysics behind the success of this treatment largely have focused on increased wound blood flow, increased granulation tissue formation, decreased bacterial counts, and stimulation of wound healing pathways through shear stress mechanisms. The overall success of negative pressure wound therapy has led to a multitude of clinical applications, which are discussed in this article. PMID:17967622

  18. The Negative Repetition Effect

    ERIC Educational Resources Information Center

    Mulligan, Neil W.; Peterson, Daniel J.

    2013-01-01

    A fundamental property of human memory is that repetition enhances memory. Peterson and Mulligan (2012) recently documented a surprising "negative repetition effect," in which participants who studied a list of cue-target pairs twice recalled fewer targets than a group who studied the pairs only once. Words within a pair rhymed, and…

  19. [Chemotherapies of negative schizophrenia].

    PubMed

    Petit, M; Dollfus, S

    1991-01-01

    Five years ago, Goldberg claimed that negative symptoms of schizophrenia do respond to neuroleptics. This apparent discovery is, in fact, a very common way of thinking for European schools of psychiatry, specially the French one guided by Delay and Deniker. Initially focused on reserpine and some alerting phenothiazines such as thioproperazine, this opinion has been extended to benzamides in the 1970s. The analysis of the publications devoted to this point indicates that several drugs are actually considered as potent disinhibitors (i.e. active on negative symptoms of schizophrenia): Phenothiazines: As shown in the controlled studies by Itil (1971), Poirier-Littré (1988), fluphenazine and pipotiazine improve the BPRS anergia factor and the SANS score. Butyrophenones: The first description of the "imipramine like" effect of trifluperidol by Janssen (1959) initiated the studies by Gallant (1960), Fox (1963). They compared trifluperidol at low doses versus haloperidol and chlorpromazine at medium and high doses, BPRS anergia factor improved only at low doses. Diphenylbutylpiperidines (DPBP): Meltzer's review (1986) concluded to the efficacy of such drugs on negative symptoms appearing as a specific biochemical relationship effect. A definite analysis about doses leads to a very different interpretation: DPBP low doses and only low doses improved negative symptoms as much as some low doses of phenothiazines. On the opposite, DPBP, phenothiazines and butyrophenones high doses are inefficient.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1683624

  20. Action Learning, Performativity and Negative Capability

    ERIC Educational Resources Information Center

    Edmonstone, John

    2016-01-01

    The paper examines the concept of negative capability as a human capacity for containment and contrasts it with well-valued positive capability as expressed through performativity in organisations and society. It identifies the problem of dispersal--the complex ways we behave in order to avoid the emotional challenges of living with uncertainty.…

  1. [Negative pressure wound therapy - review].

    PubMed

    Gudmundsdottir, Ingibjorg; Steingrimsson, Steinn; Valsdottir, Elsa; Gudbjartsson, Tomas

    2014-04-01

    Negative pressure wound therapy (NPWT) is a new therapeutic option in wound healing and was first described in its present form in 1997. A vacuum source is used to create sub-atmospheric pressure in the local wound environment to promote healing. This is achieved by connecting a vacuum pump to a tube that is threaded into a wound gauze or foam filler dressing covered with a drape. This concept in wound treatment has been shown to be useful in treating different wound infections, including diabetic wounds as well as complex infections of the abdomen and thorax. NPWT has been used in Iceland for over a decade and its use is steadily increasing. This review describes the indications and outcome of NPWT and is aimed at a broad group of doctors and nurses where recent Icelandic studies on the subject are covered. PMID:24713539

  2. Dynamically variable negative stiffness structures

    PubMed Central

    Churchill, Christopher B.; Shahan, David W.; Smith, Sloan P.; Keefe, Andrew C.; McKnight, Geoffrey P.

    2016-01-01

    Variable stiffness structures that enable a wide range of efficient load-bearing and dexterous activity are ubiquitous in mammalian musculoskeletal systems but are rare in engineered systems because of their complexity, power, and cost. We present a new negative stiffness–based load-bearing structure with dynamically tunable stiffness. Negative stiffness, traditionally used to achieve novel response from passive structures, is a powerful tool to achieve dynamic stiffness changes when configured with an active component. Using relatively simple hardware and low-power, low-frequency actuation, we show an assembly capable of fast (<10 ms) and useful (>100×) dynamic stiffness control. This approach mitigates limitations of conventional tunable stiffness structures that exhibit either small (<30%) stiffness change, high friction, poor load/torque transmission at low stiffness, or high power active control at the frequencies of interest. We experimentally demonstrate actively tunable vibration isolation and stiffness tuning independent of supported loads, enhancing applications such as humanoid robotic limbs and lightweight adaptive vibration isolators. PMID:26989771

  3. Dynamically variable negative stiffness structures.

    PubMed

    Churchill, Christopher B; Shahan, David W; Smith, Sloan P; Keefe, Andrew C; McKnight, Geoffrey P

    2016-02-01

    Variable stiffness structures that enable a wide range of efficient load-bearing and dexterous activity are ubiquitous in mammalian musculoskeletal systems but are rare in engineered systems because of their complexity, power, and cost. We present a new negative stiffness-based load-bearing structure with dynamically tunable stiffness. Negative stiffness, traditionally used to achieve novel response from passive structures, is a powerful tool to achieve dynamic stiffness changes when configured with an active component. Using relatively simple hardware and low-power, low-frequency actuation, we show an assembly capable of fast (<10 ms) and useful (>100×) dynamic stiffness control. This approach mitigates limitations of conventional tunable stiffness structures that exhibit either small (<30%) stiffness change, high friction, poor load/torque transmission at low stiffness, or high power active control at the frequencies of interest. We experimentally demonstrate actively tunable vibration isolation and stiffness tuning independent of supported loads, enhancing applications such as humanoid robotic limbs and lightweight adaptive vibration isolators. PMID:26989771

  4. Negative refraction and superconductivity

    NASA Astrophysics Data System (ADS)

    Amariti, Antonio; Forcella, Davide; Mariotti, Alberto; Siani, Massimo

    2011-10-01

    We discuss exotic properties of charged hydrodynamical systems, in the broken superconducting phase, probed by electromagnetic waves. Motivated by general arguments from hydrodynamics, we observe that negative refraction, namely the propagation in opposite directions of the phase velocities and of the energy flux, is expected for low enough frequencies. We corroborate this general idea by analyzing a holographic superconductor in the AdS/CFT correspondence, where the response functions can be explicitly computed. We study the dual gravitational theory both in the probe and in the backreacted case. We find that, while in the first case the refractive index is positive at every frequency, in the second case there is negative refraction at low enough frequencies. This is in agreement with hydrodynamic considerations.

  5. Think (Gram) negative!

    PubMed Central

    2010-01-01

    The increasing prevalence of multiresistant Gram-negative bacteria of the Enterobacteriaceae family in Europe is a worrisome phenomenon. Extended spectrum betalactamase-producing Escherichia coli strains are widespread in the community and are frequently imported into the hospital. Of even more concern is the spread of carbapenem-resistant strains of Klebsiella spp. from regions where they are already endemic. Antibiotic use is a main driver of antibiotic resistance, which again increases broad spectrum antibiotic use, resulting in a vicious circle that is difficult to interrupt. The present commentary highlights important findings of a surveillance study of antimicrobial use and resistance in German ICUs over 8 years with a focus on Gram-negative resistance. PMID:20587087

  6. Negative Emissions Technology

    NASA Astrophysics Data System (ADS)

    Day, Danny

    2006-04-01

    Although `negative emissions' of carbon dioxide need not, in principle, involve use of biological processes to draw carbon out of the atmosphere, such `agricultural' sequestration' is the only known way to remove carbon from the atmosphere on time scales comparable to the time scale for anthropogenic increases in carbon emissions. In order to maintain the `negative emissions' the biomass must be used in such a way that the resulting carbon dioxide is separated and permanently sequestered. Two options for sequestration are in the topsoil and via geologic carbon sequestration. The former has multiple benefits, but the latter also is needed. Thus, although geologic carbon sequestration is viewed skeptically by some environmentalists as simply a way to keep using fossil fuels---it may be a key part of reversing accelerating climate forcing if rapid climate change is beginning to occur. I will first review the general approach of agricultural sequestration combined with use of resulting biofuels in a way that permits carbon separation and then geologic sequestration as a negative emissions technology. Then I discuss the process that is the focus of my company---the EPRIDA cycle. If deployed at a sufficiently large scale, it could reverse the increase in CO2 concentrations. I also estimate of benefits --carbon and other---of large scale deployment of negative emissions technologies. For example, using the EPRIDA cycle by planting and soil sequestering carbon in an area abut In 3X the size of Texas would remove the amount of carbon that is being accumulated worldwide each year. In addition to the atmospheric carbon removal, the EPRIDA approach also counters the depletion of carbon in the soil---increasing topsoil and its fertility; reduces the excess nitrogen in the water by eliminating the need for ammonium nitrate fertilizer and reduces fossil fuel reliance by providing biofuel and avoiding natural gas based fertilizer production.

  7. The negative repetition effect.

    PubMed

    Mulligan, Neil W; Peterson, Daniel J

    2013-09-01

    A fundamental property of human memory is that repetition enhances memory. Peterson and Mulligan (2012) recently documented a surprising negative repetition effect, in which participants who studied a list of cue-target pairs twice recalled fewer targets than a group who studied the pairs only once. Words within a pair rhymed, and across pairs, the target words were drawn from a small set of categories. In the repetition condition, the pairs were initially presented in a random order and then presented a 2nd time blocked by the category of the target words. In the single presentation condition, the pairs were presented only in the blocked order. Participants in the former condition recalled fewer target words on a free recall test despite having seen the word pairs twice (the negative repetition effect). This phenomenon is explored in a series of 5 experiments assessing 3 theoretical accounts of the effect. The experiments demonstrate that the negative repetition effect generalizes over multiple encoding conditions (reading and generative encoding), over different memory tests (free and cued recall), and over delay (5 min and 2 days). The results argue against a retrieval account and a levels-of-processing account but are consistent with the item-specific-relational account, the account upon which the effect was initially predicated. PMID:23421508

  8. Management of insecticide resistance in control of the Simulium damnosum complex by the Onchocerciasis Control Programme, West Africa: potential use of negative correlation between organophosphate resistance and pyrethroid susceptibility.

    PubMed

    Kurtak, D; Meyer, R; Ocran, M; Ouédraogo, M; Renaud, P; Sawadogo, R O; Télé, B

    1987-04-01

    1. Resistance of some populations of the Simulium damnosum complex to temephos (100-fold at the LC50 level), with degrees of cross-resistance to chlorphoxim (14-fold) and other organophosphate insecticides, follows intensive larvicidal control of S. damnosum s.l. in West African river systems since 1975 by the WHO Onchocerciasis Control Programme. 2. Larvae of at least three sibling species of the S. damnosum complex have become organophosphate-resistant: these are the forest species S. sanctipauli Vajime & Dunbar and the savanna species S. sirbanum V. & D. and S. damnosum Theobald sensu stricto. 3. Organophosphate-resistant S. damnosum s.l. larvae show increased susceptibility to some organochlorine and pyrethroid insecticides, especially to permethrin (up to 11-fold) and OMS 3002 (up to 17-fold), as compared with organophosphate-susceptible populations. 4. This differential susceptibility is reflected by increased pyrethroid efficacy in operational use for river treatments against organophosphate-resistant field populations of S. damnosum s.l. larvae. Treatment of 100 km of the lower Bandama River in 1985 showed that permethrin at the highly selective dosage of 10 min exposure to 0.01 mg/l caused reversion towards organophosphate-susceptibility of the target population of S. sanctipauli. This effect was less pronounced when the Comoe River was treated at the lower dosage of 0.005 mg/l for 10 min. 5. To overcome temephos-resistance, it is proposed that the most rational usage of currently available larvicides would involve the following annual sequence of treatments: Bacillus thuringiensis serotype H-14 when river discharge is below 75 m3/s; chlorphoxim for about eight weekly treatment cycles after river discharge rises; permethrin (or alternative pyrethroid) for up to six treatment cycles--this should eliminate any incipient selection for chlorphoxim-resistance; resume chlorphoxim (or perhaps carbosulfan) treatments until river discharge falls below 75 m3/s

  9. Saccharomyces cerevisiae putative G protein, Gtr1p, which forms complexes with itself and a novel protein designated as Gtr2p, negatively regulates the Ran/Gsp1p G protein cycle through Gtr2p.

    PubMed Central

    Nakashima, N; Noguchi, E; Nishimoto, T

    1999-01-01

    Prp20p and Rna1p are GDP/GTP exchanging and GTPase-activating factors of Gsp1p, respectively, and their mutations, prp20-1 and rna1-1, can both be suppressed by Saccharomyces cerevisiae gtr1-11. We found that gtr1-11 caused a single amino acid substitution in Gtr1p, forming S20L, which is a putative GDP-bound mutant protein, while Gtr1p has been reported to bind to GTP alone. Consistently, gtr1-S20N, another putative GDP-bound mutant, suppressed both prp20-1 and rna1-1. On the other hand, gtr1-Q65L, a putative GTP-bound mutant, was inhibitory to prp20-1 and rna1-1. Thus, the role that Gtr1p plays in vivo appears to depend upon the nucleotide bound to it. Our data suggested that the GTP-bound Gtr1p, but not the GDP-bound Gtr1p, interacts with itself through its C-terminal tail. S. cerevisiae possesses a novel gene, GTR2, which is homologous to GTR1. Gtr2p interacts with itself in the presence of Gtr1p. The disruption of GTR2 suppressed prp20-1 and abolished the inhibitory effect of gtr1-Q65L on prp20-1. This finding, taken together with the fact that Gtr1p-S20L is a putative, inactive GDP-bound mutant, implies that Gtr1p negatively regulates the Ran/Gsp1p GTPase cycle through Gtr2p. PMID:10388807

  10. Negated bio-events: analysis and identification

    PubMed Central

    2013-01-01

    Background Negation occurs frequently in scientific literature, especially in biomedical literature. It has previously been reported that around 13% of sentences found in biomedical research articles contain negation. Historically, the main motivation for identifying negated events has been to ensure their exclusion from lists of extracted interactions. However, recently, there has been a growing interest in negative results, which has resulted in negation detection being identified as a key challenge in biomedical relation extraction. In this article, we focus on the problem of identifying negated bio-events, given gold standard event annotations. Results We have conducted a detailed analysis of three open access bio-event corpora containing negation information (i.e., GENIA Event, BioInfer and BioNLP’09 ST), and have identified the main types of negated bio-events. We have analysed the key aspects of a machine learning solution to the problem of detecting negated events, including selection of negation cues, feature engineering and the choice of learning algorithm. Combining the best solutions for each aspect of the problem, we propose a novel framework for the identification of negated bio-events. We have evaluated our system on each of the three open access corpora mentioned above. The performance of the system significantly surpasses the best results previously reported on the BioNLP’09 ST corpus, and achieves even better results on the GENIA Event and BioInfer corpora, both of which contain more varied and complex events. Conclusions Recently, in the field of biomedical text mining, the development and enhancement of event-based systems has received significant interest. The ability to identify negated events is a key performance element for these systems. We have conducted the first detailed study on the analysis and identification of negated bio-events. Our proposed framework can be integrated with state-of-the-art event extraction systems. The

  11. Polarized negative ions

    SciTech Connect

    Haeberli, W.

    1981-04-01

    This paper presents a survey of methods, commonly in use or under development, to produce beams of polarized negative ions for injection into accelerators. A short summary recalls how the hyperfine interaction is used to obtain nuclear polarization in beams of atoms. Atomic-beam sources for light ions are discussed. If the best presently known techniques are incorporated in all stages of the source, polarized H/sup -/ and D/sup -/ beams in excess of 10 ..mu..A can probably be achieved. Production of polarized ions from fast (keV) beams of polarized atoms is treated separately for atoms in the H(25) excited state (Lamb-Shift source) and atoms in the H(1S) ground state. The negative ion beam from Lamb-Shift sources has reached a plateau just above 1 ..mu..A, but this beam current is adequate for many applications and the somewhat lower beam current is compensated by other desirable characteristics. Sources using fast polarized ground state atoms are in a stage of intense development. The next sections summarize production of polarized heavy ions by the atomic beam method, which is well established, and by optical pumping, which has recently been demonstrated to yield very large nuclear polarization. A short discussion of proposed ion sources for polarized /sup 3/He/sup -/ ions is followed by some concluding remarks.

  12. Negative Entropy of Life

    NASA Astrophysics Data System (ADS)

    Goradia, Shantilal

    2015-10-01

    We modify Newtonian gravity to probabilistic quantum mechanical gravity to derive strong coupling. If this approach is valid, we should be able to extend it to the physical body (life) as follows. Using Boltzmann equation, we get the entropy of the universe (137) as if its reciprocal, the fine structure constant (ALPHA), is the hidden candidate representing the negative entropy of the universe which is indicative of the binary information as its basis (http://www.arXiv.org/pdf/physics0210040v5). Since ALPHA relates to cosmology, it must relate to molecular biology too, with the binary system as the fundamental source of information for the nucleotides of the DNA as implicit in the book by the author: ``Quantum Consciousness - The Road to Reality.'' We debate claims of anthropic principle based on the negligible variation of ALPHA and throw light on thermodynamics. We question constancy of G in multiple ways.

  13. Negative Optical Torque

    NASA Astrophysics Data System (ADS)

    Chen, Jun; Ng, Jack; Ding, Kun; Fung, Kin Hung; Lin, Zhifang; Chan, C. T.

    2014-09-01

    Light carries angular momentum, and as such it can exert torques on material objects. Applications of these opto-mechanical effects were limited initially due to their smallness in magnitude, but later becomes powerful and versatile after the invention of laser. Novel and practical approaches for harvesting light for particle rotation have since been demonstrated, where the structure is always subjected to a positive optical torque along a certain axis if the incident angular momentum has a positive projection on the same axis. We report here an interesting phenomenon of ``negative optical torque'', meaning that incoming photons carrying angular momentum rotate an object in the opposite sense. Surprisingly this can be realized quite straightforwardly in simple planar structures. Field retardation is a necessary condition and discrete rotational symmetry of material object plays an important role. The optimal conditions are explored and explained.

  14. Negative ion source

    DOEpatents

    Leung, K.N.; Ehlers, K.W.

    1982-08-06

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field.

  15. Negative ion source

    DOEpatents

    Leung, K.N.; Ehlers, K.W.

    1984-12-04

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field. 14 figs.

  16. Negative ion source

    DOEpatents

    Leung, Ka-Ngo; Ehlers, Kenneth W.

    1984-01-01

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field.

  17. Negative Optical Torque

    PubMed Central

    Chen, Jun; Ng, Jack; Ding, Kun; Fung, Kin Hung; Lin, Zhifang; Chan, C. T.

    2014-01-01

    Light carries angular momentum, and as such it can exert torques on material objects. Applications of these opto-mechanical effects were limited initially due to their smallness in magnitude, but later becomes powerful and versatile after the invention of laser. Novel and practical approaches for harvesting light for particle rotation have since been demonstrated, where the structure is always subjected to a positive optical torque along a certain axis if the incident angular momentum has a positive projection on the same axis. We report here an interesting phenomenon of “negative optical torque”, meaning that incoming photons carrying angular momentum rotate an object in the opposite sense. Surprisingly this can be realized quite straightforwardly in simple planar structures. Field retardation is a necessary condition and discrete rotational symmetry of material object plays an important role. The optimal conditions are explored and explained. PMID:25226863

  18. Do `negative' temperatures exist?

    NASA Astrophysics Data System (ADS)

    Lavenda, B. H.

    1999-06-01

    A modification of the second law is required for a system with a bounded density of states and not the introduction of a `negative' temperature scale. The ascending and descending branches of the entropy versus energy curve describe particle and hole states, having thermal equations of state that are given by the Fermi and logistic distributions, respectively. Conservation of energy requires isentropic states to be isothermal. The effect of adiabatically reversing the field is entirely mechanical because the only difference between the two states is their energies. The laws of large and small numbers, leading to the normal and Poisson approximations, characterize statistically the states of infinite and zero temperatures, respectively. Since the heat capacity also vanishes in the state of maximum disorder, the third law can be generalized in systems with a bounded density of states: the entropy tends to a constant as the temperature tends to either zero or infinity.

  19. 19. Print from copy negative (original glass plate negative in ...

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

    19. Print from copy negative (original glass plate negative in Tippecanoe County Historical Society.) Original photo dated May 7, 1893. View north, south side. - Big Four Depot, 10 South Second Street, Lafayette, Tippecanoe County, IN

  20. Negative Expertise: Comparing Differently Tenured Elder Care Nurses' Negative Knowledge

    ERIC Educational Resources Information Center

    Gartmeier, Martin; Lehtinen, Erno; Gruber, Hans; Heid, Helmut

    2011-01-01

    Negative expertise is conceptualised as the professional's ability to avoid errors during practice due to certain cognitive agencies. In this study, negative knowledge (i.e. knowledge about what is wrong in a certain context and situation) is conceptualised as one such agency. This study compares and investigates the negative knowledge of elder…

  1. Coagulase-Negative Staphylococci

    PubMed Central

    Heilmann, Christine; Peters, Georg

    2014-01-01

    SUMMARY The definition of the heterogeneous group of coagulase-negative staphylococci (CoNS) is still based on diagnostic procedures that fulfill the clinical need to differentiate between Staphylococcus aureus and those staphylococci classified historically as being less or nonpathogenic. Due to patient- and procedure-related changes, CoNS now represent one of the major nosocomial pathogens, with S. epidermidis and S. haemolyticus being the most significant species. They account substantially for foreign body-related infections and infections in preterm newborns. While S. saprophyticus has been associated with acute urethritis, S. lugdunensis has a unique status, in some aspects resembling S. aureus in causing infectious endocarditis. In addition to CoNS found as food-associated saprophytes, many other CoNS species colonize the skin and mucous membranes of humans and animals and are less frequently involved in clinically manifested infections. This blurred gradation in terms of pathogenicity is reflected by species- and strain-specific virulence factors and the development of different host-defending strategies. Clearly, CoNS possess fewer virulence properties than S. aureus, with a respectively different disease spectrum. In this regard, host susceptibility is much more important. Therapeutically, CoNS are challenging due to the large proportion of methicillin-resistant strains and increasing numbers of isolates with less susceptibility to glycopeptides. PMID:25278577

  2. Improved negative ion source

    DOEpatents

    Delmore, J.E.

    1984-05-01

    A method and apparatus for providing a negative ion source accelerates electrons away from a hot filament electron emitter into a region of crossed electric and magnetic fields arranged in a magnetron configuration. During a portion of the resulting cycloidal path, the electron velocity is reduced below its initial value. The electron accelerates as it leaves the surface at a rate of only slightly less than if there were no magnetic field, thereby preventing a charge buildup at the surface of the emitter. As the electron traverses the cycloid, it is decelerated during the second, third, and fourth quadrants, then reaccelerated as it approaches the end of the fourth quadrant to regain its original velocity. The minimum velocity occurs during the fourth quadrant, and corresponds to an electron temperature of 200 to 500/sup 0/C for the electric and magnetic fields commonly encountered in the ion sources of magnetic sector mass spectrometers. An ion source using the above-described thermalized electrons is also disclosed.

  3. Plasmonics without negative dielectrics

    NASA Astrophysics Data System (ADS)

    Della Giovampaola, Cristian; Engheta, Nader

    2016-05-01

    Plasmonic phenomena are exhibited in light-matter interaction involving materials whose real parts of permittivity functions attain negative values at operating wavelengths. However, such materials usually suffer from dissipative losses, thus limiting the performance of plasmon-based optical devices. Here, we utilize an alternative methodology that mimics a variety of plasmonic phenomena by exploiting the well-known structural dispersion of electromagnetic modes in bounded guided-wave structures filled with only materials with positive permittivity. A key issue in the design of such structures is prevention of mode coupling, which can be achieved by implementing thin metallic wires at proper interfaces. This method, which is more suitable for lower frequencies, allows designers to employ conventional dielectrics and highly conductive metals for which the loss is low at these frequencies, while achieving plasmonic features. We demonstrate, numerically and analytically, that this platform can provide surface plasmon polaritons, local plasmonic resonance, plasmonic cloaking, and epsilon-near-zero-based tunneling using conventional positive-dielectric materials.

  4. Coagulase-negative staphylococci.

    PubMed

    Becker, Karsten; Heilmann, Christine; Peters, Georg

    2014-10-01

    The definition of the heterogeneous group of coagulase-negative staphylococci (CoNS) is still based on diagnostic procedures that fulfill the clinical need to differentiate between Staphylococcus aureus and those staphylococci classified historically as being less or nonpathogenic. Due to patient- and procedure-related changes, CoNS now represent one of the major nosocomial pathogens, with S. epidermidis and S. haemolyticus being the most significant species. They account substantially for foreign body-related infections and infections in preterm newborns. While S. saprophyticus has been associated with acute urethritis, S. lugdunensis has a unique status, in some aspects resembling S. aureus in causing infectious endocarditis. In addition to CoNS found as food-associated saprophytes, many other CoNS species colonize the skin and mucous membranes of humans and animals and are less frequently involved in clinically manifested infections. This blurred gradation in terms of pathogenicity is reflected by species- and strain-specific virulence factors and the development of different host-defending strategies. Clearly, CoNS possess fewer virulence properties than S. aureus, with a respectively different disease spectrum. In this regard, host susceptibility is much more important. Therapeutically, CoNS are challenging due to the large proportion of methicillin-resistant strains and increasing numbers of isolates with less susceptibility to glycopeptides. PMID:25278577

  5. Negative Pressure Wound Therapy

    PubMed Central

    2006-01-01

    Executive Summary Objective This review was conducted to assess the effectiveness of negative pressure wound therapy. Clinical Need: Target Population and Condition Many wounds are difficult to heal, despite medical and nursing care. They may result from complications of an underlying disease, like diabetes; or from surgery, constant pressure, trauma, or burns. Chronic wounds are more often found in elderly people and in those with immunologic or chronic diseases. Chronic wounds may lead to impaired quality of life and functioning, to amputation, or even to death. The prevalence of chronic ulcers is difficult to ascertain. It varies by condition and complications due to the condition that caused the ulcer. There are, however, some data on condition-specific prevalence rates; for example, of patients with diabetes, 15% are thought to have foot ulcers at some time during their lives. The approximate community care cost of treating leg ulcers in Canada, without reference to cause, has been estimated at upward of $100 million per year. Surgically created wounds can also become chronic, especially if they become infected. For example, the reported incidence of sternal wound infections after median sternotomy is 1% to 5%. Abdominal surgery also creates large open wounds. Because it is sometimes necessary to leave these wounds open and allow them to heal on their own (secondary intention), some may become infected and be difficult to heal. Yet, little is known about the wound healing process, and this makes treating wounds challenging. Many types of interventions are used to treat wounds. Current best practice for the treatment of ulcers and other chronic wounds includes debridement (the removal of dead or contaminated tissue), which can be surgical, mechanical, or chemical; bacterial balance; and moisture balance. Treating the cause, ensuring good nutrition, and preventing primary infection also help wounds to heal. Saline or wet-to-moist dressings are reported as

  6. Conservatives, liberals, and "the negative".

    PubMed

    Charney, Evan

    2014-06-01

    The authors connect conservatism with aversion to negativity via the tendentious use of the language of threats to characterize conservatism, but not liberalism. Their reliance upon an objective conception of the negative ignores the fact that much of the disagreement between liberals and conservatives is over whether or not one and the same state of affairs is negative or positive. PMID:24970432

  7. Negativity bias and basic values.

    PubMed

    Schwartz, Shalom H

    2014-06-01

    Basic values explain more variance in political attitudes and preferences than other personality and sociodemographic variables. The values most relevant to the political domain are those likely to reflect the degree of negativity bias. Value conflicts that represent negativity bias clarify differences between what worries conservatives and liberals and suggest that relations between ideology and negativity bias are linear. PMID:24970450

  8. Negative-ion source applications.

    PubMed

    Ishikawa, J

    2008-02-01

    In this paper heavy negative-ion sources which we developed and their applications for materials science are reviewed. Heavy negative ions can be effectively produced by the ejection of a sputtered atom through the optimally cesiated surface of target with a low work function. Then, enough continuous negative-ion currents for materials-science applications can be obtained. We developed several kinds of sputter-type heavy negative-ion sources such as neutral- and ionized-alkaline metal bombardment-type heavy negative-ion source and rf-plasma sputter type. In the case where a negative ion is irradiated on a material surface, surface charging seldom takes place because incoming negative charge of the negative ion is well balanced with outgoing negative charge of the released secondary electron. In the negative-ion implantation into an insulator or insulated conductive material, high precision implantation processing with charge-up free properties can be achieved. Negative-ion implantation technique, therefore, can be applied to the following novel material processing systems: the surface modification of micrometer-sized powders, the nanoparticle formation in an insulator for the quantum devices, and the nerve cell growth manipulation by precise control of the biocompatibility of polymer surface. When a negative ion with low kinetic energy approaches the solid surface, the kinetic energy causes the interatomic bonding (kinetic bonding), and formation of a metastable material is promoted. Carbon films with high constituent of sp(3) bonding, therefore, can be formed by carbon negative-ion beam deposition. PMID:18315249

  9. Negative hydrogen ion production mechanisms

    SciTech Connect

    Bacal, M.; Wada, M.

    2015-06-15

    Negative hydrogen/deuterium ions can be formed by processes occurring in the plasma volume and on surfaces facing the plasma. The principal mechanisms leading to the formation of these negative ions are dissociative electron attachment to ro-vibrationally excited hydrogen/deuterium molecules when the reaction takes place in the plasma volume, and the direct electron transfer from the low work function metal surface to the hydrogen/deuterium atoms when formation occurs on the surface. The existing theoretical models and reported experimental results on these two mechanisms are summarized. Performance of the negative hydrogen/deuterium ion sources that emerged from studies of these mechanisms is reviewed. Contemporary negative ion sources do not have negative ion production electrodes of original surface type sources but are operated with caesium with their structures nearly identical to volume production type sources. Reasons for enhanced negative ion current due to caesium addition to these sources are discussed.

  10. 24. Duplicate negative of an historic negative. 'AERIAL VIEW OF ...

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

    24. Duplicate negative of an historic negative. 'AERIAL VIEW OF AREA 'B' HOLSTON ORDNANCE WORKS.' 1944. #OCMH 4-12.2ASAV3 in Super Explosives Program RDX and Its Composition A, B, & C, Record Group No. 319, National Archives, Washington, D.C. - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  11. Negative cooperativity in regulatory enzymes.

    PubMed

    Levitzki, A; Koshland, D E

    1969-04-01

    Negative cooperativity has been observed in CTP synthetase, an allosteric enzyme which contains a regulatory site. Thus, the same enzyme exhibits negative cooperativity for GTP (an effector) and glutamine (a substrate) and positive cooperativity for ATP and UTP (both substrates). In the process of the delineation of these phenomena, diagnostic procedures for negative cooperativity were developed. Application of these procedures to other enzymes indicates that negative cooperativity is a characteristic of many of them. These findings add strong support for the sequential model of subunit interactions which postulates that ligand-induced conformational changes are responsible for regulatory and cooperative phenomena in enzymes. PMID:5256410

  12. Negative ions of polyatomic molecules.

    PubMed Central

    Christophorou, L G

    1980-01-01

    In this paper general concepts relating to, and recent advances in, the study of negative ions of polyatomic molecules area discussed with emphasis on halocarbons. The topics dealt with in the paper are as follows: basic electron attachment processes, modes of electron capture by molecules, short-lived transient negative ions, dissociative electron attachment to ground-state molecules and to "hot" molecules (effects of temperature on electron attachment), parent negative ions, effect of density, nature, and state of the medium on electron attachment, electron attachment to electronically excited molecules, the binding of attached electrons to molecules ("electron affinity"), and the basic and the applied significance of negative-ion studies. PMID:7428744

  13. Intrinsic Negative Mass from Nonlinearity

    NASA Astrophysics Data System (ADS)

    Di Mei, F.; Caramazza, P.; Pierangeli, D.; Di Domenico, G.; Ilan, H.; Agranat, A. J.; Di Porto, P.; DelRe, E.

    2016-04-01

    We propose and provide experimental evidence of a mechanism able to support negative intrinsic effective mass. The idea is to use a shape-sensitive nonlinearity to change the sign of the mass in the leading linear propagation equation. Intrinsic negative-mass dynamics is reported for light beams in a ferroelectric crystal substrate, where the diffusive photorefractive nonlinearity leads to a negative-mass Schrödinger equation. The signature of inverted dynamics is the observation of beams repelled from strongly guiding integrated waveguides irrespective of wavelength and intensity and suggests shape-sensitive nonlinearity as a basic mechanism leading to intrinsic negative mass.

  14. [Negative symptoms of schizophrenia: historical aspects].

    PubMed

    Pringuey, D; Paquin, N; Cherikh, F; Giordana, B; Belzeaux, R; Cermolacce, M; Adida, M; Azorin, J-M

    2015-12-01

    The history of negative symptoms of schizophrenia rises early days of medicine in clinical and pathophysiological differences between positive and negative and their complex joint. Forming a set of typical core of symptoms, and some feature of a syndrome belonging to a specific pathophysiological mechanism, negative symptoms of schizophrenia emerge from old descriptions of clinical pictures, related to the overall look of madness, the heart of alienation, a central sign of early dementia, gradually more precisely describing the strange nature of the autistic withdrawal and schizophrenic apragmatism. At therapeutic era, negative symptoms have taken over the positive symptoms to establish an operational criteria whose importance lies in the progressive severity of this clinical type and in their contribution to therapeutic resistance. Despite the efforts of modern typological classifications, this work rehabilitates the old concept of "unitary psychosis" by defining a common symptomatic core to multiple clinical forms of psychosis, combining deficit of emotional expression and avolition, meaning a native psychopathology and a pathophysiology possibly in a common final way, and calling the arrival of new treatment strategies. PMID:26776389

  15. Negation in the Chaamling Language.

    ERIC Educational Resources Information Center

    Rai, Vishnu S.

    This paper examines the different ways of forming negative sentences in the Chaamling language, an indigenous language spoken in the eastern, hilly districts of Nepal. It explains that negation, or negativization, in the Chaamling language is done with the help of affixation. In imperative sentences, the prefix mi- is added to the verb, which is…

  16. Current concepts in negative pressure wound therapy.

    PubMed

    Howe, Lisa M

    2015-05-01

    Negative pressure wound therapy (NPWT) is becoming recognized in veterinary medicine as a viable option for the management of complex wounds. NPWT has many advantages over traditional wound care and results in quicker and improved wound healing in many instances. This article discusses the art and science of NPWT, as well as the many current indications, complications, advantages and disadvantages, and future directions of NPWT in small animal veterinary medicine. This therapy will likely have a growing role in veterinary medical practice for complicated wound management and other usages in coming years. PMID:25744142

  17. Negative ions at Titan and Enceladus: recent results.

    PubMed

    Coates, Andrew J; Wellbrock, Anne; Lewis, Gethyn R; Jones, Geraint H; Young, David T; Crary, Frank J; Waite, J Hunter; Johnson, Robert E; Hille, Thomas W; Sittler, Edward C

    2010-01-01

    The detection of heavy negative ions (up to 13 800 amu) in Titan's ionosphere is one of the tantalizing new results from the Cassini mission. These heavy ions indicate for the first time the existence of heavy hydrocarbon and nitrile molecules in this primitive Earth-like atmosphere. These ions were suggested to be precursors of aerosols in Titan's atmosphere and may precipitate to the surface as tholins. We present the evidence for and the analysis of these heavy negative ions at Titan. In addition we examine the variation of the maximum mass of the Titan negative ions with altitude and latitude for the relevant encounters so far, and we discuss the implications for the negative ion formation process. We present data from a recent set of encounters where the latitude was varied between encounters, with other parameters fixed. Models are beginning to explain the low mass negative ions, but the formation process for the higher mass ions is still not understood. It is possible that the structures may be chains, rings or even fullerenes. Negative ions, mainly water clusters in this case, were seen during Cassini's recent close flybys of Enceladus. We present mass spectra from the Enceladus plume, showing water clusters and additional species. As at Titan, the negative ions indicate chemical complexities which were unknown before the Cassini encounters, and are indicative of a complex balance between neutrals and positively and negatively charged ions. PMID:21302552

  18. Three chamber negative ion source

    DOEpatents

    Leung, Ka-Ngo; Ehlers, Kenneth W.; Hiskes, John R.

    1985-01-01

    A negative ion vessel is divided into an excitation chamber, a negative ionization chamber and an extraction chamber by two magnetic filters. Input means introduces neutral molecules into a first chamber where a first electron discharge means vibrationally excites the molecules which migrate to a second chamber. In the second chamber a second electron discharge means ionizes the molecules, producing negative ions which are extracted into or by a third chamber. A first magnetic filter prevents high energy electrons from entering the negative ionization chamber from the excitation chamber. A second magnetic filter prevents high energy electrons from entering the extraction chamber from the negative ionizing chamber. An extraction grid at the end of the negative ion vessel attracts negative ions into the third chamber and accelerates them. Another grid, located adjacent to the extraction grid, carries a small positive voltage in order to inhibit positive ions from migrating into the extraction chamber and contour the plasma potential. Additional electrons can be suppressed from the output flux using ExB forces provided by magnetic field means and the extractor grid electric potential.

  19. Isotropic Negative Thermal Expansion Metamaterials.

    PubMed

    Wu, Lingling; Li, Bo; Zhou, Ji

    2016-07-13

    Negative thermal expansion materials are important and desirable in science and engineering applications. However, natural materials with isotropic negative thermal expansion are rare and usually unsatisfied in performance. Here, we propose a novel method to achieve two- and three-dimensional negative thermal expansion metamaterials via antichiral structures. The two-dimensional metamaterial is constructed with unit cells that combine bimaterial strips and antichiral structures, while the three-dimensional metamaterial is fabricated by a multimaterial 3D printing process. Both experimental and simulation results display isotropic negative thermal expansion property of the samples. The effective coefficient of negative thermal expansion of the proposed models is demonstrated to be dependent on the difference between the thermal expansion coefficient of the component materials, as well as on the circular node radius and the ligament length in the antichiral structures. The measured value of the linear negative thermal expansion coefficient of the three-dimensional sample is among the largest achieved in experiments to date. Our findings provide an easy and practical approach to obtaining materials with tunable negative thermal expansion on any scale. PMID:27333052

  20. Lower body negative pressure device

    NASA Technical Reports Server (NTRS)

    Nolte, R. W.

    1977-01-01

    The Lower Body Negative Pressure Device was used, in the space environment, to stress the astronaut's cardiovascular system, to determine the extent and time course of his cardiovascular deconditioning and to determine whether in-flight data from experiment M092, Lower Body Negative Pressure, would be useful in predicting postflight status of orthostatic tolerance. The lower portion of the subject's body was enclosed in this device for the purpose of applying regulated and controlled negative pressure. A description is given of the device.

  1. Piezoelectric enhancement under negative pressure

    NASA Astrophysics Data System (ADS)

    Kvasov, Alexander; McGilly, Leo J.; Wang, Jin; Shi, Zhiyong; Sandu, Cosmin S.; Sluka, Tomas; Tagantsev, Alexander K.; Setter, Nava

    2016-07-01

    Enhancement of ferroelectric properties, both spontaneous polarization and Curie temperature under negative pressure had been predicted in the past from first principles and recently confirmed experimentally. In contrast, piezoelectric properties are expected to increase by positive pressure, through polarization rotation. Here we investigate the piezoelectric response of the classical PbTiO3, Pb(Zr,Ti)O3 and BaTiO3 perovskite ferroelectrics under negative pressure from first principles and find significant enhancement. Piezoelectric response is then tested experimentally on free-standing PbTiO3 and Pb(Zr,Ti)O3 nanowires under self-sustained negative pressure, confirming the theoretical prediction. Numerical simulations verify that negative pressure in nanowires is the origin of the enhanced electromechanical properties. The results may be useful in the development of highly performing piezoelectrics, including lead-free ones.

  2. Piezoelectric enhancement under negative pressure.

    PubMed

    Kvasov, Alexander; McGilly, Leo J; Wang, Jin; Shi, Zhiyong; Sandu, Cosmin S; Sluka, Tomas; Tagantsev, Alexander K; Setter, Nava

    2016-01-01

    Enhancement of ferroelectric properties, both spontaneous polarization and Curie temperature under negative pressure had been predicted in the past from first principles and recently confirmed experimentally. In contrast, piezoelectric properties are expected to increase by positive pressure, through polarization rotation. Here we investigate the piezoelectric response of the classical PbTiO3, Pb(Zr,Ti)O3 and BaTiO3 perovskite ferroelectrics under negative pressure from first principles and find significant enhancement. Piezoelectric response is then tested experimentally on free-standing PbTiO3 and Pb(Zr,Ti)O3 nanowires under self-sustained negative pressure, confirming the theoretical prediction. Numerical simulations verify that negative pressure in nanowires is the origin of the enhanced electromechanical properties. The results may be useful in the development of highly performing piezoelectrics, including lead-free ones. PMID:27396411

  3. Factors identified for negative appendicectomies.

    PubMed

    Mirza, M R; Habib, L; Jaleel, F

    2009-07-01

    The study was done, to determine the factors for negative appendicectomies. This prospective descriptive study includes patients managed at four non teaching and a teaching hospital of Karachi from March 2006 to February 2008. One hundred and sixty eight patients underwent appendicectomy during the study period. Details of clinical presentations, investigations, operative findings and histopathology were entered and analyzed. Literature search was aimed to see the negative appendicectomy rate (NAR) in last ten years despite using diagnostic tools (clinical scoring, diagnostic imaging and laparoscopy). In this study a total number of 168 patients under went appendicectomy. Normal appendices were found in 31 patients (negative appendicectomy rate was 18.45%) and associated pathology was seen in 13 patients, an incidental finding of Meckel's diverticulum in 5 patients and no other pathology was seen in 13 patients. The different factors which we identified for negative appendicectomies in our practice were non teaching hospitals where diagnostic scoring system was difficult to apply, female gender, selective use of imaging modality, other pathologies presenting with pain in right lower quadrant (RLQ) and requiring surgical intervention, and non-availability of CT scan and laparoscopy. Despite many advances in diagnostic system, acute appendicitis is still a diagnostic dilemma at times. Although there is no substitute for clinical judgment but in sub groups of patients in whom the possibility of negative appendicectomy is high, diagnostic modalities should be used judiciously to decrease the negative exploration. PMID:19623147

  4. Optical Refraction in Silver: Counterposition, Negative Phase Velocity and Orthogonal Phase Velocity

    ERIC Educational Resources Information Center

    Naqvi, Qaisar A.; Mackay, Tom G.; Lakhtakia, Akhlesh

    2011-01-01

    Complex behaviour associated with metamaterials can arise even in commonplace isotropic dielectric materials. We demonstrate how silver, for example, can support negative phase velocity and counterposition, but not negative refraction, at optical frequencies. The transition from positive to negative phase velocity is not accompanied by remarkable…

  5. Negative Transportation and Cross-Linguistic Negative Evidence.

    ERIC Educational Resources Information Center

    Soga, Matsuo

    1972-01-01

    This paper considers whether the negative transportation (NT) rule operating in English is operative also in Japanese and whether investigation of the phenomenon in Japanese may provide new insights for English research. The discussion begins with an explanation and examples of the NT rule in English. Japanese cases are then studied, and the…

  6. Negativity Bias in Dangerous Drivers

    PubMed Central

    Chai, Jing; Qu, Weina; Sun, Xianghong; Zhang, Kan; Ge, Yan

    2016-01-01

    The behavioral and cognitive characteristics of dangerous drivers differ significantly from those of safe drivers. However, differences in emotional information processing have seldom been investigated. Previous studies have revealed that drivers with higher anger/anxiety trait scores are more likely to be involved in crashes and that individuals with higher anger traits exhibit stronger negativity biases when processing emotions compared with control groups. However, researchers have not explored the relationship between emotional information processing and driving behavior. In this study, we examined the emotional information processing differences between dangerous drivers and safe drivers. Thirty-eight non-professional drivers were divided into two groups according to the penalty points that they had accrued for traffic violations: 15 drivers with 6 or more points were included in the dangerous driver group, and 23 drivers with 3 or fewer points were included in the safe driver group. The emotional Stroop task was used to measure negativity biases, and both behavioral and electroencephalograph data were recorded. The behavioral results revealed stronger negativity biases in the dangerous drivers than in the safe drivers. The bias score was correlated with self-reported dangerous driving behavior. Drivers with strong negativity biases reported having been involved in mores crashes compared with the less-biased drivers. The event-related potentials (ERPs) revealed that the dangerous drivers exhibited reduced P3 components when responding to negative stimuli, suggesting decreased inhibitory control of information that is task-irrelevant but emotionally salient. The influence of negativity bias provides one possible explanation of the effects of individual differences on dangerous driving behavior and traffic crashes. PMID:26765225

  7. Sigma models with negative curvature

    NASA Astrophysics Data System (ADS)

    Alonso, Rodrigo; Jenkins, Elizabeth E.; Manohar, Aneesh V.

    2016-05-01

    We construct Higgs Effective Field Theory (HEFT) based on the scalar manifold Hn, which is a hyperbolic space of constant negative curvature. The Lagrangian has a non-compact O (n , 1) global symmetry group, but it gives a unitary theory as long as only a compact subgroup of the global symmetry is gauged. Whether the HEFT manifold has positive or negative curvature can be tested by measuring the S-parameter, and the cross sections for longitudinal gauge boson and Higgs boson scattering, since the curvature (including its sign) determines deviations from Standard Model values.

  8. Negative Geography: Locating Things Elsewhere.

    ERIC Educational Resources Information Center

    Stoddard, Robert H.

    The phenomenon of negative geography--the assertion that any location is better than the one selected--is discussed and ways in which this approach differs from traditional geography methodology are analyzed. Case studies of two citizens' groups which protested the relocation of a city mission and halfway house in their neighborhoods illustrate…

  9. Cosmic Complexity

    NASA Technical Reports Server (NTRS)

    Mather, John C.

    2012-01-01

    neutrons, liberating a little energy and creating complexity. Then, the expanding universe cooled some more, and neutrons and protons, no longer kept apart by immense temperatures, found themselves unstable and formed helium nuclei. Then, a little more cooling, and atomic nuclei and electrons were no longer kept apart, and the universe became transparent. Then a little more cooling, and the next instability began: gravitation pulled matter together across cosmic distances to form stars and galaxies. This instability is described as a "negative heat capadty" in which extracting energy from a gravitating system makes it hotter -- clearly the 2nd law of thermodynamics does not apply here! (This is the physicist's part of the answer to e e cummings' question: what is the wonder that's keeping the stars apart?) Then, the next instability is that hydrogen and helium nuclei can fuse together to release energy and make stars burn for billions of years. And then at the end of the fuel source, stars become unstable and explode and liberate the chemical elements back into space. And because of that, on planets like Earth, sustained energy flows support the development of additional instabilities and all kinds of complex patterns. Gravitational instability pulls the densest materials into the core of the Earth, leaving a thin skin of water and air, and makes the interior churn incessantly as heat flows outwards. And the heat from the sun, received mostly near the equator and flowing towards the poles, supports the complex atmospheric and oceanic circulations. And because or that, the physical Earth is full of natural chemical laboratories, concentrating elements here, mixing them there, raising and lowering temperatures, ceaselessly experimenting with uncountable events where new instabilities can arise. At least one of them was the new experiment called life. Now that we know that there are at least as many planets as there are stars, it is hard to imagine that nature's ceasess

  10. Cosmic Complexity

    NASA Technical Reports Server (NTRS)

    Mather, John C.

    2012-01-01

    neutrons, liberating a little energy and creating complexity. Then, the expanding universe cooled some more, and neutrons and protons, no longer kept apart by immense temperatures, found themselves unstable and formed helium nuclei. Then, a little more cooling, and atomic nuclei and electrons were no longer kept apart, and the universe became transparent. Then a little more cooling, and the next instability began: gravitation pulled matter together across cosmic distances to form stars and galaxies. This instability is described as a "negative heat capadty" in which extracting energy from a gravitating system makes it hotter -- clearly the 2nd law of thermodynamics does not apply here! (This is the physicist's part of the answer to e e cummings' question: what is the wonder that's keeping the stars apart?) Then, the next instability is that hydrogen and helium nuclei can fuse together to release energy and make stars burn for billions of years. And then at the end of the fuel source, stars become unstable and explode and liberate the chemical elements back into space. And because of that, on planets like Earth, sustained energy flows support the development of additional instabilities and all kinds of complex patterns. Gravitational instability pulls the densest materials into the core of the Earth, leaving a thin skin of water and air, and makes the interior churn incessantly as heat flows outwards. And the heat from the sun, received mostly near the equator and flowing towards the poles, supports the complex atmospheric and oceanic circulations. And because or that, the physical Earth is full of natural chemical laboratories, concentrating elements here, mixing them there, raising and lowering temperatures, ceaselessly experimenting with uncountable events where new instabilities can arise. At least one of them was the new experiment called life. Now that we know that there are at least as many planets as there are stars, it is hard to imagine that nature's ceasess

  11. Metalinguistic Negation in English and Arabic

    ERIC Educational Resources Information Center

    Nedwick, Kelly M.

    2014-01-01

    Negation is a unique and fascinating property of human language which has been given extensive theoretical and typological treatment. One categorization divides negation use into metalinguistic negation and descriptive negation (Horn, 1985). Descriptive negation (DN) is the truth-functional semantic operator which has received the most attention…

  12. Drawing Inferences from Semantically Positive and Negative Implicative Predicates.

    ERIC Educational Resources Information Center

    Vosniadou, Stella

    A study investigated the inferential processing involved in the comprehension of a class of complex predicates (such as "remember to,""manage to,""fail to," and "neglect to") that are known as implicative. The subjects, 64 college students, were timed while they drew inferences from syntactically affirmative and negative sentences containing the…

  13. Negative magnetophoresis in diluted ferrofluid flow.

    PubMed

    Hejazian, Majid; Nguyen, Nam-Trung

    2015-07-21

    We report magnetic manipulation of non-magnetic particles suspended in diluted ferrofluid. Diamagnetic particles were introduced into a circular chamber to study the extent of their deflection under the effect of a non-uniform magnetic field of a permanent magnet. Since ferrofluid is a paramagnetic medium, it also experiences a bulk magnetic force that in turn induces a secondary flow opposing the main hydrodynamic flow. Sheath flow rate, particle size, and magnetic field strength were varied to examine this complex behaviour. The combined effect of negative magnetophoresis and magnetically induced secondary flow leads to various operation regimes, which can potentially find applications in separation, trapping and mixing of diamagnetic particles such as cells in a microfluidic system. PMID:26054840

  14. Negative pressure therapy: theory and practice.

    PubMed

    Schintler, M V

    2012-02-01

    Negative pressure (wound) therapy, synonymous with topical negative pressure or vacuum therapy mainly cited as branded VAC® (vacuum-assisted closure) therapy, is a mode of therapy used to encourage wound healing. It is used both as primary treatment of chronic and complex wounds and as an adjunct for temporary closure and wound bed preparation preceding surgical procedures such as skin grafts and flap surgery. The device has come into wide and successful use, although the physiological basis of its effect is not yet fully understood, and with a delay, increasingly evidence-based data become available. A meta-analysis was made of peer-reviewed publications (PubMed-Medline) chosen on the basis of inclusion of the terms randomized clinical trial, vacuum-assisted closure, and topical negative pressure. Scientific data were evaluated from experimental animal studies, randomized clinical trials, observations of clinical applications, and case reports on all known effects of VAC therapy. Systematic analysis of the data shows efficacy concerning induction of wound healing mechanisms, especially in the early stage. Increased perfusion can be considered proven. Data analysis shows positive efficacy for treatment of infection. Although this therapy appears effective and its superiority to conventional techniques has been demonstrated, there are still some critical votes concerning efficacy. Because its mechanisms of action remain unclear, and because there is still some gap between evidence-based data and the excellent clinical results, further prospective, randomized, blinded studies are needed. Even so, we conclude that vacuum therapy, used when indicated and especially by experienced surgeons, is an excellent tool to support wound healing. PMID:22271727

  15. Cosmology with negative absolute temperatures

    NASA Astrophysics Data System (ADS)

    Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony

    2016-08-01

    Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w < ‑1) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.

  16. Gram-Negative Flagella Glycosylation

    PubMed Central

    Merino, Susana; Tomás, Juan M.

    2014-01-01

    Protein glycosylation had been considered as an eccentricity of a few bacteria. However, through advances in analytical methods and genome sequencing, it is now established that bacteria possess both N-linked and O-linked glycosylation pathways. Both glycosylation pathways can modify multiple proteins, flagellins from Archaea and Eubacteria being one of these. Flagella O-glycosylation has been demonstrated in many polar flagellins from Gram-negative bacteria and in only the Gram-positive genera Clostridium and Listeria. Furthermore, O-glycosylation has also been demonstrated in a limited number of lateral flagellins. In this work, we revised the current advances in flagellar glycosylation from Gram-negative bacteria, focusing on the structural diversity of glycans, the O-linked pathway and the biological function of flagella glycosylation. PMID:24557579

  17. Negative effects of positive reinforcement

    PubMed Central

    Perone, Michael

    2003-01-01

    Procedures classified as positive reinforcement are generally regarded as more desirable than those classified as aversive—those that involve negative reinforcement or punishment. This is a crude test of the desirability of a procedure to change or maintain behavior. The problems can be identified on the basis of theory, experimental analysis, and consideration of practical cases. Theoretically, the distinction between positive and negative reinforcement has proven difficult (some would say the distinction is untenable). When the distinction is made purely in operational terms, experiments reveal that positive reinforcement has aversive functions. On a practical level, positive reinforcement can lead to deleterious effects, and it is implicated in a range of personal and societal problems. These issues challenge us to identify other criteria for judging behavioral procedures. ImagesFigure 1Figure 2 PMID:22478391

  18. In defense of negative temperature

    NASA Astrophysics Data System (ADS)

    Poulter, J.

    2016-03-01

    This pedagogical comment highlights three misconceptions concerning the usefulness of the concept of negative temperature, being derived from the usual, often termed Boltzmann, definition of entropy. First, both the Boltzmann and Gibbs entropies must obey the same thermodynamic consistency relation. Second, the Boltzmann entropy does obey the second law of thermodynamics. Third, there exists an integrating factor of the heat differential with both definitions of entropy.

  19. Complexity Survey.

    ERIC Educational Resources Information Center

    Gordon, Sandra L.; Anderson, Beth C.

    To determine whether consensus existed among teachers about the complexity of common classroom materials, a survey was administered to 66 pre-service and in-service kindergarten and prekindergarten teachers. Participants were asked to rate 14 common classroom materials as simple, complex, or super-complex. Simple materials have one obvious part,…

  20. Negative mass solitons in gravity

    NASA Astrophysics Data System (ADS)

    Cebeci, Hakan; Sarıoǧlu, Özgür; Tekin, Bayram

    2006-03-01

    We first reconstruct the conserved (Abbott-Deser) charges in the spin-connection formalism of gravity for asymptotically (Anti)-de Sitter spaces, and then compute the masses of the AdS soliton and the recently found Eguchi-Hanson solitons in generic odd dimensions, unlike the previous result obtained for only five dimensions. These solutions have negative masses compared to the global AdS or AdS/Zp spacetimes. As a separate note, we also compute the masses of the recent even dimensional Taub-NUT-Reissner-Nordström metrics.

  1. Imagery mismatch negativity in musicians.

    PubMed

    Herholz, Sibylle C; Lappe, Claudia; Knief, Arne; Pantev, Christo

    2009-07-01

    The present study investigated musical imagery in musicians and nonmusicians by means of magnetoencephalography (MEG). We used a new paradigm in which subjects had to continue familiar melodies in their mind and then judged if a further presented tone was a correct continuation of the melody. Incorrect tones elicited an imagery mismatch negativity (iMMN) in musicians but not in nonmusicians. This finding suggests that the MMN component can be based on an imagined instead of a sensory memory trace and that imagery of music is modulated by musical expertise. PMID:19673775

  2. Communication complexity and information complexity

    NASA Astrophysics Data System (ADS)

    Pankratov, Denis

    Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information

  3. A Special Sort of Forgetting: Negation in Freud and Augustine.

    PubMed

    Rosengart, Daniel

    2016-04-01

    The development from a positive, dualistic theory of memory and forgetting to a concept of memory that includes forgetting as a variety of remembering is traced in two thinkers. Freud's concept of repression is discussed as a complex negation of both remembering and forgetting, and the development of this construct is shown in his letters to Wilhelm Fliess. A close reading of Augustine of Hippo's Confessions shows a similar concept of a special sort of forgetting, in which what is forgotten is remembered nonetheless. Finally, the limits of the comparison are discussed, and a reading of Freud's "Negation" reveals ways in which the unconscious is fundamentally unlike Augustine's interiority. PMID:27009296

  4. Negative regulators of cell proliferation

    NASA Technical Reports Server (NTRS)

    Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Cell proliferation is governed by the influence of both mitogens and inhibitors. Although cell contact has long been thought to play a fundamental role in cell cycling regulation, and negative regulators have long been suspected to exist, their isolation and purification has been complicated by a variety of technical difficulties. Nevertheless, over recent years an ever-expanding list of putative negative regulators have emerged. In many cases, their biological inhibitory activities are consistent with density-dependent growth inhibition. Most likely their interactions with mitogenic agents, at an intracellular level, are responsible for either mitotic arrest or continued cell cycling. A review of naturally occurring cell growth inhibitors is presented with an emphasis on those factors shown to be residents of the cell surface membrane. Particular attention is focused on a cell surface sialoglycopeptide, isolated from intact bovine cerebral cortex cells, which has been shown to inhibit the proliferation of an unusually wide range of target cells. The glycopeptide arrest cells obtained from diverse species, both fibroblasts and epithelial cells, and a broad variety of transformed cells. Signal transduction events and a limited spectrum of cells that are refractory to the sialoglycopeptide have provided insight into the molecular events mediated by this cell surface inhibitor.

  5. Photosynthesis and negative entropy production.

    PubMed

    Jennings, Robert C; Engelmann, Enrico; Garlaschi, Flavio; Casazza, Anna Paola; Zucchelli, Giuseppe

    2005-09-30

    The widely held view that the maximum efficiency of a photosynthetic pigment system is given by the Carnot cycle expression (1-T/Tr) for energy transfer from a hot bath (radiation at temperature Tr) to a cold bath (pigment system at temperature T) is critically examined and demonstrated to be inaccurate when the entropy changes associated with the microscopic process of photon absorption and photochemistry at the level of single photosystems are considered. This is because entropy losses due to excited state generation and relaxation are extremely small (DeltaS < T/Tr) and are essentially associated with the absorption-fluorescence Stokes shift. Total entropy changes associated with primary photochemistry for single photosystems are shown to depend critically on the thermodynamic efficiency of the process. This principle is applied to the case of primary photochemistry of the isolated core of higher plant photosystem I and photosystem II, which are demonstrated to have maximal thermodynamic efficiencies of xi > 0.98 and xi > 0.92 respectively, and which, in principle, function with negative entropy production. It is demonstrated that for the case of xi > (1-T/Tr) entropy production is always negative and only becomes positive when xi < (1-T/Tr). PMID:16139784

  6. Instrumentation for negative ion detection.

    PubMed

    McKeown, M

    1980-06-01

    The instrumentation and practical circuitry required for the detection of negative ions exiting the mass analysis section of a mass spectrometer is examined. The potentials needed to bias the electron multiplier when detecting negative ions from a low ion-energy mass spectrometer, e.g., a quadrupole, are contrasted with the biasing requirements of a mass spectrometer having high ion-energies, e.g., a magnetic sector. Methods of decoupling the biasing high voltage on the signal lead of the multiplier in pulse counting measurements are discussed in detail so that normal, ground referenced input, pulse preamplifiers may be used. Easily understood, practical rules for determining the values of circuit components are given together with a simplified theory of transferring pulse signals from multiplier collector to pulse preamplifier. The changes in circuitry needed when attempting to detect ions by current measurement methods from an electron multiplier area detailed. The effects of leakage currents into athe input of the current preamplifier and their avoidance bay using triaxial shielding on vacuum feed-throughs are explained. The article suggests possible methods of decoupling the high voltage referenced input and the ground referenced output of a current measuring preamplifier. PMID:7428750

  7. Mismatch Negativity: Translating the Potential

    PubMed Central

    Todd, Juanita; Harms, Lauren; Schall, Ulrich; Michie, Patricia T.

    2013-01-01

    The mismatch negativity (MMN) component of the auditory event-related potential has become a valuable tool in cognitive neuroscience. Its reduced size in persons with schizophrenia is of unknown origin but theories proposed include links to problems in experience-dependent plasticity reliant on N-methyl-d-aspartate glutamate receptors. In this review we address the utility of this tool in revealing the nature and time course of problems in perceptual inference in this illness together with its potential for use in translational research testing animal models of schizophrenia-related phenotypes. Specifically, we review the reasons for interest in MMN in schizophrenia, issues pertaining to the measurement of MMN, its use as a vulnerability index for the development of schizophrenia, the pharmacological sensitivity of MMN and the progress in developing animal models of MMN. Within this process we highlight the challenges posed by knowledge gaps pertaining to the tool and the pharmacology of the underlying system. PMID:24391602

  8. Entanglement negativity in the multiverse

    SciTech Connect

    Kanno, Sugumi; Shock, Jonathan P.; Soda, Jiro

    2015-03-10

    We explore quantum entanglement between two causally disconnected regions in the multiverse. We first consider a free massive scalar field, and compute the entanglement negativity between two causally separated open charts in de Sitter space. The qualitative feature of it turns out to be in agreement with that of the entanglement entropy. We then introduce two observers who determine the entanglement between two causally disconnected de Sitter spaces. When one of the observers remains constrained to a region of the open chart in a de Sitter space, we find that the scale dependence enters into the entanglement. We show that a state which is initially maximally entangled becomes more entangled or less entangled on large scales depending on the mass of the scalar field and recovers the initial entanglement in the small scale limit. We argue that quantum entanglement may provide some evidence for the existence of the multiverse.

  9. Entanglement negativity in the multiverse

    NASA Astrophysics Data System (ADS)

    Kanno, Sugumi; Shock, Jonathan P.; Soda, Jiro

    2015-03-01

    We explore quantum entanglement between two causally disconnected regions in the multiverse. We first consider a free massive scalar field, and compute the entanglement negativity between two causally separated open charts in de Sitter space. The qualitative feature of it turns out to be in agreement with that of the entanglement entropy. We then introduce two observers who determine the entanglement between two causally disconnected de Sitter spaces. When one of the observers remains constrained to a region of the open chart in a de Sitter space, we find that the scale dependence enters into the entanglement. We show that a state which is initially maximally entangled becomes more entangled or less entangled on large scales depending on the mass of the scalar field and recovers the initial entanglement in the small scale limit. We argue that quantum entanglement may provide some evidence for the existence of the multiverse.

  10. Tools to assess negative symptoms in schizophrenia.

    PubMed

    Kane, John M

    2013-06-01

    Although effective treatments for negative symptoms are currently limited, clinicians still need to assess and monitor them because of their impact on patient functioning. Further, documenting patients' negative symptoms provides a complete clinical record that the clinician can use to make systematic and careful treatment decisions. Several tools for assessing negative symptoms in schizophrenia are available, including the Clinical Global Impression scale (CGI), the Brief Psychiatric Rating Scale (BPRS), the Positive and Negative Syndrome Scale (PANSS), the Scale for the Assessment of Negative Symptoms (SANS), the 16-item Negative Symptoms Assessment (NSA-16), and the Schedule for Deficit Syndrome (SDS). Additionally, newer instruments are in development-the Clinical Assessment Interview for Negative Symptoms (CAINS) and the Brief Negative Symptoms Scale (BNSS)-and are yielding promising results. This overview outlines these assessment tools so that clinicians can measure negative symptom severity and track treatment response for their patients with schizophrenia. PMID:23842020

  11. Complex derivatives

    NASA Astrophysics Data System (ADS)

    Battiston, Stefano; Caldarelli, Guido; Georg, Co-Pierre; May, Robert; Stiglitz, Joseph

    2013-03-01

    The intrinsic complexity of the financial derivatives market has emerged as both an incentive to engage in it, and a key source of its inherent instability. Regulators now faced with the challenge of taming this beast may find inspiration in the budding science of complex systems.

  12. Designing Complexity

    ERIC Educational Resources Information Center

    Glanville, Ranulph

    2007-01-01

    This article considers the nature of complexity and design, as well as relationships between the two, and suggests that design may have much potential as an approach to improving human performance in situations seen as complex. It is developed against two backgrounds. The first is a world view that derives from second order cybernetics and radical…

  13. Identification of candidate genes associated with positive and negative heterosis in rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heterosis is a complex biological phenomenon in which the offspring show superior performance compared to the inbred parents. Heterosis can be positive or negative. To identify the genes related to positive and negative heterosis, massively parallel signature sequencing (MPSS) libraries were constru...

  14. The Morpho-Syntax and Pragmatics of Levantine Arabic Negation: A Synchronic and Diachronic Analysis

    ERIC Educational Resources Information Center

    Alqassas, Ahmad

    2012-01-01

    This dissertation investigates the morphosyntax and pragmatics of Levantine Arabic negation from both a synchronic and a diachronic perspective. It is shown that the complex distribution of the negation morphemes "ma," "la" and "-sh" is subject to morphosyntactic and pragmatic constraints. The morphosyntactic…

  15. 14 CFR 25.943 - Negative acceleration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Negative acceleration. 25.943 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.943 Negative acceleration. No... the negative accelerations within the flight envelopes prescribed in § 25.333. This must be shown...

  16. 14 CFR 23.943 - Negative acceleration.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Negative acceleration. 23.943 Section 23... Negative acceleration. No hazardous malfunction of an engine, an auxiliary power unit approved for use in... the airplane is operated at the negative accelerations within the flight envelopes prescribed in §...

  17. 14 CFR 23.943 - Negative acceleration.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Negative acceleration. 23.943 Section 23... Negative acceleration. No hazardous malfunction of an engine, an auxiliary power unit approved for use in... the airplane is operated at the negative accelerations within the flight envelopes prescribed in §...

  18. 14 CFR 23.943 - Negative acceleration.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Negative acceleration. 23.943 Section 23... Negative acceleration. No hazardous malfunction of an engine, an auxiliary power unit approved for use in... the airplane is operated at the negative accelerations within the flight envelopes prescribed in §...

  19. 14 CFR 25.943 - Negative acceleration.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Negative acceleration. 25.943 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.943 Negative acceleration. No... the negative accelerations within the flight envelopes prescribed in § 25.333. This must be shown...

  20. 14 CFR 25.943 - Negative acceleration.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Negative acceleration. 25.943 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.943 Negative acceleration. No... the negative accelerations within the flight envelopes prescribed in § 25.333. This must be shown...

  1. 14 CFR 25.943 - Negative acceleration.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Negative acceleration. 25.943 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.943 Negative acceleration. No... the negative accelerations within the flight envelopes prescribed in § 25.333. This must be shown...

  2. 14 CFR 25.943 - Negative acceleration.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Negative acceleration. 25.943 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.943 Negative acceleration. No... the negative accelerations within the flight envelopes prescribed in § 25.333. This must be shown...

  3. 14 CFR 23.943 - Negative acceleration.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Negative acceleration. 23.943 Section 23... Negative acceleration. No hazardous malfunction of an engine, an auxiliary power unit approved for use in... the airplane is operated at the negative accelerations within the flight envelopes prescribed in §...

  4. 14 CFR 23.943 - Negative acceleration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Negative acceleration. 23.943 Section 23... Negative acceleration. No hazardous malfunction of an engine, an auxiliary power unit approved for use in... the airplane is operated at the negative accelerations within the flight envelopes prescribed in §...

  5. Negative dimensional integrals. I. Feynman graphs

    NASA Astrophysics Data System (ADS)

    Halliday, I. G.; Ricotta, R. M.

    1987-07-01

    We propose a new method of evaluating integrals based on negative dimensional integration. We compute Feynman graphs by considering analytic extensions. Propagators are raised to negative integer powers and integrated over negative integer dimensions. We are left with the problem of computing polynomial integrals and summing finite series.

  6. 40 CFR 62.06 - Negative declarations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Negative declarations. 62.06 Section 62....06 Negative declarations. A State may submit to the Administrator a letter certifying that no designated facilities exist in the State if such is the case. The negative declaration will be in lieu of...

  7. Electric Potential Near The Extraction Region In Negative Ion Sources With Surface Produced Negative Ions

    SciTech Connect

    Fukano, A.; Hatayama, A.

    2011-09-26

    The potential distribution near the extraction region in negative ion sources for the plasma with the surface produced negative ions is studied analytically. The potential is derived analytically by using a plasma-sheath equation, where negative ions produced on the Plasma Grid (PG) surface are considered in addition to positive ions and electrons. A negative potential peak is formed in the sheath region near the PG surface for the case of strong surface production of negative ions or for low energy negative ions. Negative ions are reflected by the negative potential peak near the PG and returned to the PG surface. This reflection mechanism by the negative potential peak possibly becomes a factor in negative ion extraction. It is also indicated that the potential difference between the plasma region and the wall decreases by the surface produced negative ions. This also has the possibility to contribute to the negative ion extraction.

  8. Negative ions in the coma of Comet Halley

    NASA Technical Reports Server (NTRS)

    Chaizy, P.; Reme, H.; Sauvaud, J. A.; D'Uston, C.; Lin, R. P.

    1991-01-01

    The detection of negatively charged cometary ions in the inner coma of Comet Halley is reported. These ions are observed in three broad mass peaks at 7-19, 22-65, and 85-110 AMU, with densities reaching greater than about 1/cu cm, about 0.05/cu cm, and about 0.04/cu cm, respectively, at a distance of about 2300 km from the nucleus. The ion species thought to be present include O(-), OH(-), C(-), CH(-), CN(-) and heavier complex CHO molecular ions. As negative ions are easily destroyed by solar radiation at about 1 AU, an efficient production mechanism, so far unidentified, is required to account for the observed densities. The detection of negative ions in the coma near 1 AU implies that negative ions should also be present in similar neutral gas and dust environment farther away from the sun. If the negative-ion densities are large enough, they could play an important part in physical processes such as radiative transfer or charge exchange.

  9. A circuit mechanism for differentiating positive and negative associations.

    PubMed

    Namburi, Praneeth; Beyeler, Anna; Yorozu, Suzuko; Calhoon, Gwendolyn G; Halbert, Sarah A; Wichmann, Romy; Holden, Stephanie S; Mertens, Kim L; Anahtar, Melodi; Felix-Ortiz, Ada C; Wickersham, Ian R; Gray, Jesse M; Tye, Kay M

    2015-04-30

    The ability to differentiate stimuli predicting positive or negative outcomes is critical for survival, and perturbations of emotional processing underlie many psychiatric disease states. Synaptic plasticity in the basolateral amygdala complex (BLA) mediates the acquisition of associative memories, both positive and negative. Different populations of BLA neurons may encode fearful or rewarding associations, but the identifying features of these populations and the synaptic mechanisms of differentiating positive and negative emotional valence have remained unknown. Here we show that BLA neurons projecting to the nucleus accumbens (NAc projectors) or the centromedial amygdala (CeM projectors) undergo opposing synaptic changes following fear or reward conditioning. We find that photostimulation of NAc projectors supports positive reinforcement while photostimulation of CeM projectors mediates negative reinforcement. Photoinhibition of CeM projectors impairs fear conditioning and enhances reward conditioning. We characterize these functionally distinct neuronal populations by comparing their electrophysiological, morphological and genetic features. Overall, we provide a mechanistic explanation for the representation of positive and negative associations within the amygdala. PMID:25925480

  10. A Circuit Mechanism for Differentiating Positive and Negative Associations

    PubMed Central

    Namburi, Praneeth; Beyeler, Anna; Yorozu, Suzuko; Calhoon, Gwendolyn G.; Halbert, Sarah A.; Wichmann, Romy; Holden, Stephanie S.; Mertens, Kim L.; Anahtar, Melodi; Felix-Ortiz, Ada C.; Wickersham, Ian R.; Gray, Jesse M.; Tye, Kay M.

    2015-01-01

    The ability to differentiate stimuli predicting positive or negative outcomes is critical for survival, and perturbations of emotional processing underlie many psychiatric disease states. Synaptic plasticity in the basolateral amygdala complex (BLA) mediates the acquisition of associative memories, both positive1,2 and negative3–7. Different populations of BLA neurons may encode fearful or rewarding associations8–10, but the identifying features of these populations and the synaptic mechanisms of differentiating positive and negative emotional valence have remained an enigma. Here, we show that BLA neurons projecting to the nucleus accumbens (NAc projectors) or the centromedial amygdala (CeM projectors) underwent opposing synaptic changes following fear or reward conditioning. We found that photostimulation of NAc projectors supports positive reinforcement while photostimulation of CeM projectors mediates negative reinforcement. Photoinhibition of CeM projectors impaired fear conditioning and enhanced reward conditioning. We then characterized these functionally-distinct neuronal populations by comparing their electrophysiological, morphological and genetic features. We provide a mechanistic explanation for the representation of positive and negative associations within the amygdala. PMID:25925480

  11. A biopsychosocial model based on negative feedback and control

    PubMed Central

    Carey, Timothy A.; Mansell, Warren; Tai, Sara J.

    2014-01-01

    Although the biopsychosocial model has been a popular topic of discussion for over four decades it has not had the traction in fields of research that might be expected of such an intuitively appealing idea. One reason for this might be the absence of an identified mechanism or a functional architecture that is authentically biopsychosocial. What is needed is a robust mechanism that is equally important to biochemical processes as it is to psychological and social processes. Negative feedback may be the mechanism that is required. Negative feedback has been implicated in the regulation of neurotransmitters as well as important psychological and social processes such as emotional regulation and the relationship between a psychotherapist and a client. Moreover, negative feedback is purported to also govern the activity of all other organisms as well as humans. Perceptual Control Theory (PCT) describes the way in which negative feedback establishes control at increasing levels of perceptual complexity. Thus, PCT may be the first biopsychosocial model to be articulated in functional terms. In this paper we outline the working model of PCT and explain how PCT provides an embodied hierarchical neural architecture that utilizes negative feedback to control physiological, psychological, and social variables. PCT has major implications for both research and practice and, importantly, provides a guide by which fields of research that are currently separated may be integrated to bring about substantial progress in understanding the way in which the brain alters, and is altered by, its behavioral and environmental context. PMID:24616685

  12. Corrugator activity confirms immediate negative affect in surprise.

    PubMed

    Topolinski, Sascha; Strack, Fritz

    2015-01-01

    The emotion of surprise entails a complex of immediate responses, such as cognitive interruption, attention allocation to, and more systematic processing of the surprising stimulus. All these processes serve the ultimate function to increase processing depth and thus cognitively master the surprising stimulus. The present account introduces phasic negative affect as the underlying mechanism responsible for this switch in operating mode. Surprising stimuli are schema-discrepant and thus entail cognitive disfluency, which elicits immediate negative affect. This affect in turn works like a phasic cognitive tuning switching the current processing mode from more automatic and heuristic to more systematic and reflective processing. Directly testing the initial elicitation of negative affect by surprising events, the present experiment presented high and low surprising neutral trivia statements to N = 28 participants while assessing their spontaneous facial expressions via facial electromyography. High compared to low surprising trivia elicited higher corrugator activity, indicative of negative affect and mental effort, while leaving zygomaticus (positive affect) and frontalis (cultural surprise expression) activity unaffected. Future research shall investigate the mediating role of negative affect in eliciting surprise-related outcomes. PMID:25762956

  13. Corrugator activity confirms immediate negative affect in surprise

    PubMed Central

    Topolinski, Sascha; Strack, Fritz

    2015-01-01

    The emotion of surprise entails a complex of immediate responses, such as cognitive interruption, attention allocation to, and more systematic processing of the surprising stimulus. All these processes serve the ultimate function to increase processing depth and thus cognitively master the surprising stimulus. The present account introduces phasic negative affect as the underlying mechanism responsible for this switch in operating mode. Surprising stimuli are schema-discrepant and thus entail cognitive disfluency, which elicits immediate negative affect. This affect in turn works like a phasic cognitive tuning switching the current processing mode from more automatic and heuristic to more systematic and reflective processing. Directly testing the initial elicitation of negative affect by surprising events, the present experiment presented high and low surprising neutral trivia statements to N = 28 participants while assessing their spontaneous facial expressions via facial electromyography. High compared to low surprising trivia elicited higher corrugator activity, indicative of negative affect and mental effort, while leaving zygomaticus (positive affect) and frontalis (cultural surprise expression) activity unaffected. Future research shall investigate the mediating role of negative affect in eliciting surprise-related outcomes. PMID:25762956

  14. Carney Complex

    MedlinePlus

    ... Screening guidelines may change over time as new technologies are developed and more is learned about Carney complex. It is important to talk with your doctor about appropriate screening tests. Learn more about what to expect when having ...

  15. [Negative symptoms: clinical and psychometric aspects].

    PubMed

    Adida, M; Azorin, J-M; Belzeaux, R; Fakra, E

    2015-12-01

    Recent investigations performing exploratory and confirmatory factor analysis have suggested that negative symptoms are multidimensional, including evidence for at least two distinct negative symptom subdomains: diminished expression and amotivation. Guidance for selection of instruments for measurement of negative symptoms is rapidly evolving. As there are continuing advances in the description of negative symptoms, new instruments are under development, and new data on the performance of instruments emerge from clinical trials. The Scale for Assessment of Negative Symptoms (SANS), the Positive and Negative Syndrome Scale (PANSS), and the Negative Symptom Assessment-16 (NSA-16) are considered to be reliable and valid measures for negative symptom trials but differ with respect to their domain coverage, use of informants, integration of global scores, administration time and comprehensiveness of their structured interviews. In response to the 2005 NIMH - MATRICS consensus statement, work groups are field testing and refining two new measures, the Clinical Assessment Interview for Negative Symptoms (CAINS) and the Brief Negative Symptom Scale (BNSS). Both address the five currently recognized domains of negative symptoms, differentiate appetitive from consummatory aspects of anhedonia and address desire for social relationships. Thus far, both have exhibited promising psychometric properties. PMID:26776385

  16. Complex networks: Patterns of complexity

    NASA Astrophysics Data System (ADS)

    Pastor-Satorras, Romualdo; Vespignani, Alessandro

    2010-07-01

    The Turing mechanism provides a paradigm for the spontaneous generation of patterns in reaction-diffusion systems. A framework that describes Turing-pattern formation in the context of complex networks should provide a new basis for studying the phenomenon.

  17. Complex Event Recognition Architecture

    NASA Technical Reports Server (NTRS)

    Fitzgerald, William A.; Firby, R. James

    2009-01-01

    Complex Event Recognition Architecture (CERA) is the name of a computational architecture, and software that implements the architecture, for recognizing complex event patterns that may be spread across multiple streams of input data. One of the main components of CERA is an intuitive event pattern language that simplifies what would otherwise be the complex, difficult tasks of creating logical descriptions of combinations of temporal events and defining rules for combining information from different sources over time. In this language, recognition patterns are defined in simple, declarative statements that combine point events from given input streams with those from other streams, using conjunction, disjunction, and negation. Patterns can be built on one another recursively to describe very rich, temporally extended combinations of events. Thereafter, a run-time matching algorithm in CERA efficiently matches these patterns against input data and signals when patterns are recognized. CERA can be used to monitor complex systems and to signal operators or initiate corrective actions when anomalous conditions are recognized. CERA can be run as a stand-alone monitoring system, or it can be integrated into a larger system to automatically trigger responses to changing environments or problematic situations.

  18. Negation, questions, and structure building in a homesign system

    PubMed Central

    Franklin, Amy; Giannakidou, Anastasia; Goldin-Meadow, Susan

    2013-01-01

    Deaf children whose hearing losses are so severe that they cannot acquire spoken language, and whose hearing parents have not exposed them to sign language, use gestures called homesigns to communicate. Homesigns have been shown to contain many of the properties of natural languages. Here we ask whether homesign has structure building devices for negation and questions. We identify two meanings (negation, question) that correspond semantically to propositional functions, that is, to functions that apply to a sentence (whose semantic value is a proposition, φ) and yield another proposition that is more complex (¬φ for negation; ?φ for question). Combining φ with¬ or ? thus involves sentence modification. We propose that these negative and question functions are structure building operators, and we support this claim with data from an American homesigner. We show that: (a) each meaning is marked by a particular form in the child’s gesture system (side-to-side headshake for negation, manual flip for question); (b) the two markers occupy systematic, and different, positions at the periphery of the gesture sentences (headshake at the beginning, flip at the end); and (c) the flip is extended from questions to other uses associated with the wh-form (exclamatives, referential expressions of location) and thus functions like a category in natural languages. If what we see in homesign is a language creation process (Goldin-Meadow, 2003), and if negation and question formation involve sentential modification, then our analysis implies that homesign has at least this minimal sentential syntax. Our findings thus contribute to ongoing debates about properties that are fundamental to language and language learning. PMID:23630971

  19. Negation, questions, and structure building in a homesign system.

    PubMed

    Franklin, Amy; Giannakidou, Anastasia; Goldin-Meadow, Susan

    2011-03-01

    Deaf children whose hearing losses are so severe that they cannot acquire spoken language, and whose hearing parents have not exposed them to sign language, use gestures called homesigns to communicate. Homesigns have been shown to contain many of the properties of natural languages. Here we ask whether homesign has structure building devices for negation and questions. We identify two meanings (negation, question) that correspond semantically to propositional functions, that is, to functions that apply to a sentence (whose semantic value is a proposition, ϕ) and yield another proposition that is more complex (¬ϕ for negation; ?ϕ for question). Combining ϕ with ¬ or ? thus involves sentence modification. We propose that these negative and question functions are structure building operators, and we support this claim with data from an American homesigner. We show that: (a) each meaning is marked by a particular form in the child's gesture system (side-to-side headshake for negation, manual flip for question); (b) the two markers occupy systematic, and different, positions at the periphery of the gesture sentences (headshake at the beginning, flip at the end); and (c) the flip is extended from questions to other uses associated with the wh-form (exclamatives, referential expressions of location) and thus functions like a category in natural languages. If what we see in homesign is a language creation process (Goldin-Meadow, 2003), and if negation and question formation involve sentential modification, then our analysis implies that homesign has at least this minimal sentential syntax. Our findings thus contribute to ongoing debates about properties that are fundamental to language and language learning. PMID:23630971

  20. Nonlinear negative refraction by difference frequency generation

    NASA Astrophysics Data System (ADS)

    Cao, Jianjun; Shen, Dongyi; Feng, Yaming; Wan, Wenjie

    2016-05-01

    Negative refraction has attracted much interest for its promising capability in imaging applications. Such an effect can be implemented by negative index meta-materials, however, which are usually accompanied by high loss and demanding fabrication processes. Recently, alternative nonlinear approaches like phase conjugation and four wave mixing have shown advantages of low-loss and easy-to-implement, but associated problems like narrow accepting angles can still halt their practical applications. Here, we demonstrate theoretically and experimentally a scheme to realize negative refraction by nonlinear difference frequency generation with wide tunability, where a thin Beta barium borate slice serves as a negative refraction layer bending the input signal beam to the idler beam at a negative angle. Furthermore, we realize optical focusing effect using such nonlinear negative refraction, which may enable many potential applications in imaging science.

  1. Electrochemical cell and negative electrode therefor

    DOEpatents

    Kaun, Thomas D.

    1982-01-01

    A secondary electrochemical cell with the positive and negative electrodes separated by a molten salt electrolyte with the negative electrode comprising a particulate mixture of lithium-aluminum alloy and electrolyte and an additive selected from graphitized carbon, Raney iron or mixtures thereof. The lithium-aluminum alloy is present in the range of from about 45 to about 80 percent by volume of the negative electrode, and the electrolyte is present in an amount not less than about 10 percent by volume of the negative electrode. The additive of graphitized carbon is present in the range of from about 1 to about 10 percent by volume of the negative electrode, and the Raney iron additive is present in the range of from about 3 to about 10 percent by volume of the negative electrode.

  2. Production systems need negation as failure

    SciTech Connect

    Phan Minh Dung; Mancarella, P.

    1996-12-31

    We study action rule based systems with two forms of negation, namely classical negation and {open_quotes}negation as failure to find a course of actions{close_quotes}. We show by several examples that adding negation as failure to such systems increase their expressiveness, in the sense that real life problems can be represented in a natural and simple way. Then, we address the problem of providing a formal declarative semantics to these extended systems, by adopting an argumentation based approach, which has been shown to be a simple unifying framework for understanding the declarative semantics of various nonmonotonic formalisms. In this way, we naturally define the grounded (well-founded), stable and preferred semantics for production systems with negation as failure. Next, we characterize the class of stratified production systems, which enjoy the properties that the above mentioned semantics coincide and that negation as failure can be computed by a simple bottom-up operator.

  3. Dust grains potential variation in a Vasyliunas Cairns-distributed plasmas with negative ions

    NASA Astrophysics Data System (ADS)

    Abid, A. A.; Khan, M. Z.; Wong, C. S.; Yap, S. L.

    2015-12-01

    Dust grains' potential variation is presented by using a non-equilibrium complex (dusty) plasma following the Vasyliunas Cairns (VC)-distribution, in which the components such as the electrons, ions [positive and negative], and dust grains have negative charge. For this reason, mathematical statement of currents is solved for dust grains having negatively charge to accomplish the equilibrium state value (viz., qd = constant) in the presence of VC-distributed plasmas. Indeed, the current balance equations are modified due to the streaming/nonequilibrium distributed negative ions. Numerically, it is assessed that the important plasma variable, for example, spectral index α, spectral index κ , negative ions streaming velocity (U0), and negative ions number density ( ρ ) , significantly influences the dust grain surface potential ( | ψ d | ) by: (i) increasing the value of spectral index kappa ( κ ) and negative ions density ( ρ ) , the magnitude of dust surface potential ( | ψ d | ) decreases and (ii) increasing the values of spectral index α and negative ions streaming velocity (U0), dust grains surface potential ( | ψ d | ) increases. The relevance to low-temperature research center in a non-equilibrium dusty (complex) plasma is precisely discussed by associating oxygen ions (negative and positive) species.

  4. Arabinogalactan proteins are incorporated in negatively charged coffee brew melanoidins.

    PubMed

    Bekedam, E Koen; De Laat, Marieke P F C; Schols, Henk A; Van Boekel, Martinus A J S; Smit, Gerrit

    2007-02-01

    The charge properties of melanoidins in high molecular weight (HMw) coffee brew fractions, isolated by diafiltration and membrane dialysis, were studied. Ion exchange chromatography experiments with the HMw fractions showed that coffee brew melanoidins were negatively charged whereas these molecules did not expose any positive charge at the pH of coffee brew. Fractions with different ionic charges were isolated and subsequently characterized by means of the specific extinction coefficient (K(mix 405nm)), sugar composition, phenolic group content, nitrogen content, and the arabinogalactan protein (AGP) specific Yariv gel-diffusion assay. The isolated fractions were different in composition and AGP was found to be present in one of the HMw fractions. The AGP accounted for 6% of the coffee brew dry matter and had a moderate negative charge, probably caused by the presence of uronic acids. As the fraction that precipitated with Yariv was brown (K(mix 405nm) = 1.2), compared to a white color in the green bean, it was concluded that these AGPs had undergone Maillard reaction resulting in an AGP-melanoidin complex. The presence of mannose (presumably from galactomannan) indicates the incorporation of galactomannans in the AGP-melanoidin complex. As the uronic acid content in the more negatively charged melanoidin-rich, AGP-poor HMw fractions decreased, it was hypothesized that acidic groups are formed or incorporated during melanoidin formation. PMID:17263472

  5. Functional splinting of upper limb injuries with gauze-based topical negative pressure wound therapy.

    PubMed

    Taylor, Christopher J; Chester, Darren L; Jeffery, Steven L

    2011-11-01

    Complex hand injuries can be difficult to dress effectively and achieve adequate splintage of the hand in a functional position. During the past 7 years, we have had a great deal of success with topical negative-pressure dressings in the management of complex blast-related extremity war injuries. We have more recently changed to using a gauze-based system and have found this particularly useful in dressing complex hand injuries. We have been able to use this vacuum dressing system to splint the hand in a position of function. This provides an easily applied dressing that, through topical negative pressure, promotes wound healing and ensures a resting functional position, thus minimizing postoperative stiffness. We have not been able to achieve this as efficiently with standard dressings and plaster-of-Paris casts. This article details the technique of functional splinting of complex hand injuries using a gauze-based, topical negative-pressure dressing system. PMID:22036283

  6. Absolute negative mobility of interacting Brownian particles

    NASA Astrophysics Data System (ADS)

    Ou, Ya-li; Hu, Cai-tian; Wu, Jian-chun; Ai, Bao-quan

    2015-12-01

    Transport of interacting Brownian particles in a periodic potential is investigated in the presence of an ac force and a dc force. From Brownian dynamic simulations, we find that both the interaction between particles and the thermal fluctuations play key roles in the absolute negative mobility (the particle noisily moves backwards against a small constant bias). When no the interaction acts, there is only one region where the absolute negative mobility occurs. In the presence of the interaction, the absolute negative mobility may appear in multiple regions. The weak interaction can be helpful for the absolute negative mobility, while the strong interaction has a destructive impact on it.

  7. Negative refraction without absorption via quantum coherence

    NASA Astrophysics Data System (ADS)

    Fang, Ai-Ping; Ge, Wenchao; Wang, Meng; Li, Fu-li; Zubairy, M. Suhail

    2016-02-01

    Negative refraction of a probe field is studied in a dense gas consisting of cascade-type four-level atoms. By coupling the magnetic component of the probe field to a Λ scheme with initially prepared coherence in the two lower levels, strong negative permeability with minimal absorption can be obtained. The permittivity of the gas to the electric component of the probe field can be made negative by taking into account the local field effect of the dense atoms. Strong negative refraction with zero absorption can be achieved in a wide range of parameters in our scheme. A possible experimental realization is also discussed.

  8. An advanced negative hydrogen ion source.

    PubMed

    Goncharov, Alexey A; Dobrovolsky, Andrey N; Goretskii, Victor P

    2016-02-01

    The results of investigation of emission productivity of negative particles source with cesiated combined discharge are presented. A cylindrical beam of negative hydrogen ions with density about 2 A/cm(2) in low noise mode on source emission aperture is obtained. The total beam current values are up to 200 mA for negative hydrogen ions and up to 1.5 A for all negative particles with high divergence after source. The source has simple design and can produce stable discharge with low level of oscillation. PMID:26931996

  9. Researching Complexity.

    ERIC Educational Resources Information Center

    Sumara, Dennis J.

    2000-01-01

    Discusses what Complexity Theory (presented as a rubric that collects theoretical understandings from a number of domains such as ecology, biology, neurology, and education) suggests about mind, selfhood, intelligence, and practices of reading, and the import of these reconceptualizations to reader-response researchers. Concludes that developing…

  10. Complex Clouds

    Atmospheric Science Data Center

    2013-04-16

    ...     View Larger Image The complex structure and beauty of polar clouds are highlighted by these images acquired ... Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and every 9 days views the entire globe ...

  11. Amorphic complexity

    NASA Astrophysics Data System (ADS)

    Fuhrmann, G.; Gröger, M.; Jäger, T.

    2016-02-01

    We introduce amorphic complexity as a new topological invariant that measures the complexity of dynamical systems in the regime of zero entropy. Its main purpose is to detect the very onset of disorder in the asymptotic behaviour. For instance, it gives positive value to Denjoy examples on the circle and Sturmian subshifts, while being zero for all isometries and Morse-Smale systems. After discussing basic properties and examples, we show that amorphic complexity and the underlying asymptotic separation numbers can be used to distinguish almost automorphic minimal systems from equicontinuous ones. For symbolic systems, amorphic complexity equals the box dimension of the associated Besicovitch space. In this context, we concentrate on regular Toeplitz flows and give a detailed description of the relation to the scaling behaviour of the densities of the p-skeletons. Finally, we take a look at strange non-chaotic attractors appearing in so-called pinched skew product systems. Continuous-time systems, more general group actions and the application to cut and project quasicrystals will be treated in subsequent work.

  12. Complex interactions

    NASA Astrophysics Data System (ADS)

    de Régules, Sergio

    2016-04-01

    Complexity science – which describes phenomena such as collective and emergent behaviour – is the focus of a new centre where researchers are examining everything from the spread of influenza to what a healthy heartbeat looks like. Sergio de Régules reports.

  13. The RNA synthesis machinery of negative-stranded RNA viruses

    SciTech Connect

    Ortín, Juan; Martín-Benito, Jaime

    2015-05-15

    The group of Negative-Stranded RNA Viruses (NSVs) includes many human pathogens, like the influenza, measles, mumps, respiratory syncytial or Ebola viruses, which produce frequent epidemics of disease and occasional, high mortality outbreaks by transmission from animal reservoirs. The genome of NSVs consists of one to several single-stranded, negative-polarity RNA molecules that are always assembled into mega Dalton-sized complexes by association to many nucleoprotein monomers. These RNA-protein complexes or ribonucleoproteins function as templates for transcription and replication by action of the viral RNA polymerase and accessory proteins. Here we review our knowledge on these large RNA-synthesis machines, including the structure of their components, the interactions among them and their enzymatic activities, and we discuss models showing how they perform the virus transcription and replication programmes. - Highlights: • Overall organisation of NSV RNA synthesis machines. • Structure and function of the ribonucleoprotein components: Atomic structure of the RNA polymerase complex. • Commonalities and differences between segmented- and non-segmented NSVs. • Transcription versus replication programmes.

  14. 4. Photographic copy of a photograph taken from pasteup negatives ...

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

    4. Photographic copy of a photograph taken from paste-up negatives for U.S. Army Corps of Engineers document GF-500-MCP, entitled "Grand Forks Site RLS Army Operating Drawings, Master Composite Photographs for SAFEGUARD TSE Systems and Equipment," Page 9, dated 1 September 1974 (original document and negatives in possession of U.S. Army Corps of Engineers, Huntsville, AL). Photographer unknown. View of remote launch operations building exterior (southwest corner), prior to earth mounding. A,B,C, and D are heat exchangers HX-1102B, HX-1102A, HX-1101B, and HX-1101 A, respectively. The heat exchangers transferred heat from the cooling water to the outside air during the normal operating mode. On the far right is the air exhaust shaft - Stanley R. Mickelsen Safeguard Complex, Remote Launch Operations Building, Near Service Road exit from Patrol Road, Nekoma, Cavalier County, ND

  15. 5. Photographic copy of a photograph taken from pasteup negatives ...

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

    5. Photographic copy of a photograph taken from paste-up negatives for U.S. Army Corps of Engineers document GF-500-MCP, entitled "Grand Forks Site RLS Army Operating Drawings, Master Composite Photographs for SAFEGUARD TSE Systems and Equipment," Page 9, dated 1 September 1974 (original document and negatives in possession of U.S. Army Corps of Engineers, Huntsville, AL). Photographer unknown. View of pneumatic control panel regulating entrance to waiting room #116. The panel activated the pneumatic cylinder for opening and closing of blast doors #116 and #118. A rotary air motor actuated locking and unlocking of the doors. - Stanley R. Mickelsen Safeguard Complex, Remote Launch Operations Building, Near Service Road exit from Patrol Road, Nekoma, Cavalier County, ND

  16. Community detection in networks with positive and negative links

    NASA Astrophysics Data System (ADS)

    Traag, V. A.; Bruggeman, Jeroen

    2009-09-01

    Detecting communities in complex networks accurately is a prime challenge, preceding further analyses of network characteristics and dynamics. Until now, community detection took into account only positively valued links, while many actual networks also feature negative links. We extend an existing Potts model to incorporate negative links as well, resulting in a method similar to the clustering of signed graphs, as dealt with in social balance theory, but more general. To illustrate our method, we applied it to a network of international alliances and disputes. Using data from 1993-2001, it turns out that the world can be divided into six power blocs similar to Huntington’s civilizations, with some notable exceptions.

  17. 40 CFR 52.122 - Negative declarations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Negative declarations. 52.122 Section 52.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Arizona § 52.122 Negative declarations. (a) The following air pollution control districts...

  18. Negation in the brain: modulating action representations.

    PubMed

    Tettamanti, Marco; Manenti, Rosa; Della Rosa, Pasquale A; Falini, Andrea; Perani, Daniela; Cappa, Stefano F; Moro, Andrea

    2008-11-01

    Sentential negation is a universal syntactic feature of human languages that reverses the truth value expressed by a sentence. An intriguing question concerns what brain mechanisms underlie our ability to represent and understand the meaning of negative sentences. We approach this issue by investigating action-related language processing and the associated neural representations. Using functional magnetic resonance imaging we measured brain activity in 18 healthy subjects during passive listening of sentences characterized by a factorial combination of polarity (affirmative vs. negative) and concreteness (action-related vs. abstract). Negation deactivated cortical areas and the left pallidum. Compared to abstract sentences, action-related sentences activated the left-hemispheric action-representation system. Crucially, the polarity by concreteness interactions showed that the activity within the action-representation system was specifically reduced for negative action-related vs. affirmative action-related sentences (compared to abstract sentences). Accordingly, functional integration within this system as measured by Dynamic Causal Modeling was specifically weaker for negative action-related than for affirmative action-related sentences. This modulation of action representations indicates that sentential negation transiently reduces the access to mental representations of the negated information. PMID:18771737

  19. Criticism and the Ethics of Negative Reviews

    ERIC Educational Resources Information Center

    Peters, Michael A.

    2014-01-01

    This paper is an attempt to work through my own angst at a negative review of my "Education, Philosophy and Politics," reviewed recently by Ian Stronach for the "British Educational Research Journal," and to provide a therapeutic reading of the ethics of negative reviews. What of "shots in the dark" and should there…

  20. Estimation for entanglement negativity of free fermions

    NASA Astrophysics Data System (ADS)

    Herzog, Christopher P.; Wang, Yihong

    2016-07-01

    In this letter we study the negativity of one dimensional free fermions. We derive the general form of the {{{Z}}N} symmetric term in moments of the partial transposed (reduced) density matrix, which is an algebraic function of the end points of the system. Such a path integral turns out to be a convenient tool for making estimations for the negativity.

  1. Negative Knowledge: Understanding Professional Learning and Expertise

    ERIC Educational Resources Information Center

    Gartmeier, Martin; Bauer, Johannes; Gruber, Hans; Heid, Helmut

    2008-01-01

    In this paper, we critically analyze how the concept of negative knowledge contributes to the understanding of professionals' expert practice and learning. Negative knowledge is experientially acquired knowledge about what is wrong and what is to be avoided during performance in a given work situation. In terms of its theoretical foundation, the…

  2. 40 CFR 52.2900 - Negative declaration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Negative declaration. 52.2900 Section... § 52.2900 Negative declaration. (a) Air Pollution Implementation Plan for the Commonwealth of the Northern Mariana Islands. (1) Letter of December 15, 1982, from the Governor to EPA, which is a...

  3. The Negative Binomial Distribution in Quantum Physics

    NASA Astrophysics Data System (ADS)

    Söderholm, Jonas; Inoue, Shuichiro

    2009-06-01

    We give examples of situations where the negative binomial distribution has appeared in quantum physics since its debut in the work of Planck. Several of its properties are reviewed, and Mandel's Q-parameter is shown to play an interesting role. The photon-pair distributions of squeezed vacuum and squeezed single-photon states are identified as negative binomial.

  4. Negative ion spectrometry for detecting nitrated explosives

    NASA Technical Reports Server (NTRS)

    Boettger, H. G.; Yinon, J.

    1975-01-01

    Ionization procedure is modified to produce mainly negative ions by electron capture. Peaks of negative ions are monitored conventionally. Nitrated organic materials could be identified directly from sample sniff inlet stream by suitably modified mass spectrometer because of unique electronegativity which nitro group imparts to organic material.

  5. Negative Priming in Free Recall Reconsidered

    ERIC Educational Resources Information Center

    Hanczakowski, Maciej; Beaman, C. Philip; Jones, Dylan M.

    2016-01-01

    Negative priming in free recall is the finding of impaired memory performance when previously ignored auditory distracters become targets of encoding and retrieval. This negative priming has been attributed to an aftereffect of deploying inhibitory mechanisms that serve to suppress auditory distraction and minimize interference with learning and…

  6. Managing Complexity

    SciTech Connect

    Chassin, David P.; Posse, Christian; Malard, Joel M.

    2004-08-01

    Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today’s most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically-based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This paper explores the state of the art in the use physical analogs for understanding the behavior of some econophysical systems and to deriving stable and robust control strategies for them. In particular we review and discussion applications of some analytic methods based on the thermodynamic metaphor according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood.

  7. Ionization phenomena and sources of negative ions

    SciTech Connect

    Alton, G.D.

    1983-01-01

    Negative ion source technology has rapidly advanced during the past several years as a direct consequence of the discovery of Krohn that negative ion yields can be greatly enhanced by sputtering in the presence of Group IA elements. Today, most negative ion sources use this discovery directly or the principles implied to effect negative ion formation through surface ionization. As a consequence, the more traditional direct extraction plasma and charge exchange sources are being used less frequently. However, the charge exchange generation mechanism appears to be as universal, is very competitive in terms of efficiency and has the advantage in terms of metastable ion formation. In this review, an attempt has been made to briefly describe the principal processes involved in negative ion formation and sources which are representative of a particular principle. The reader is referred to the literature for specific details concerning the operational characteristics, emittances, brightnesses, species and intensity capabilities of particular sources. 100 references.

  8. Negative incidental emotions augment fairness sensitivity

    PubMed Central

    Liu, Cuizhen; Chai, Jing Wen; Yu, Rongjun

    2016-01-01

    Previous studies have shown that task-unrelated emotions induced incidentally exert carryover effects on individuals’ subsequent decisions in financial negotiations. However, the specificity of these emotion effects are not clear. In three experiments, we systematically investigated the role of seven transiently induced basic emotions (disgust, sadness, anger, fear, happiness, surprise and neutral) on rejection of unfair offers using the ultimatum game. We found that all negative emotions (disgust, sadness, anger and fear), but not happiness or surprise, significantly increased rejection rates, suggesting that the effect of incidental negative emotions on fairness is not specific to the type of negative emotion. Our findings highlight the role of fleeting emotions in biasing decision-making processes and suggest that all incidental negative emotions exert similar effects on fairness sensitivity, possibly by potentiating attention towards negative aspects of the situation. PMID:27101931

  9. Negative incidental emotions augment fairness sensitivity.

    PubMed

    Liu, Cuizhen; Chai, Jing Wen; Yu, Rongjun

    2016-01-01

    Previous studies have shown that task-unrelated emotions induced incidentally exert carryover effects on individuals' subsequent decisions in financial negotiations. However, the specificity of these emotion effects are not clear. In three experiments, we systematically investigated the role of seven transiently induced basic emotions (disgust, sadness, anger, fear, happiness, surprise and neutral) on rejection of unfair offers using the ultimatum game. We found that all negative emotions (disgust, sadness, anger and fear), but not happiness or surprise, significantly increased rejection rates, suggesting that the effect of incidental negative emotions on fairness is not specific to the type of negative emotion. Our findings highlight the role of fleeting emotions in biasing decision-making processes and suggest that all incidental negative emotions exert similar effects on fairness sensitivity, possibly by potentiating attention towards negative aspects of the situation. PMID:27101931

  10. Negative Ion Beam Extraction and Emittance

    SciTech Connect

    Holmes, Andrew J. T.

    2007-08-10

    The use of magnetic fields to both aid the production of negative ions and suppress the co-extracted electrons causes the emittance and hence the divergence of the negative ion beam to increase significantly due to the plasma non-uniformity from jxB drift. This drift distorts the beam-plasma meniscus and experimental results of the beam emittance are presented, which show that non-uniformity causes the square of the emittance to be proportional to the 2/3 power of the extracted current density. This can cause the divergence of the negative ion beam to be significantly larger than its positive ion counterpart. By comparing results from positive and negative ion beam emittances from the same source, it is also possible to draw conclusions about their vulnerability to magnetic effects. Finally emittances of caesiated and un-caesiated negative ion beams are compared to show how the surface and volume modes of production interact.

  11. Potential negative ecological effects of corridors.

    PubMed

    Haddad, Nick M; Brudvig, Lars A; Damschen, Ellen I; Evans, Daniel M; Johnson, Brenda L; Levey, Douglas J; Orrock, John L; Resasco, Julian; Sullivan, Lauren L; Tewksbury, Josh J; Wagner, Stephanie A; Weldon, Aimee J

    2014-10-01

    Despite many studies showing that landscape corridors increase dispersal and species richness for disparate taxa, concerns persist that corridors can have unintended negative effects. In particular, some of the same mechanisms that underlie positive effects of corridors on species of conservation interest may also increase the spread and impact of antagonistic species (e.g., predators and pathogens), foster negative effects of edges, increase invasion by exotic species, increase the spread of unwanted disturbances such as fire, or increase population synchrony and thus reduce persistence. We conducted a literature review and meta-analysis to evaluate the prevalence of each of these negative effects. We found no evidence that corridors increase unwanted disturbance or non-native species invasion; however, these have not been well-studied concerns (1 and 6 studies, respectively). Other effects of corridors were more often studied and yielded inconsistent results; mean effect sizes were indistinguishable from zero. The effect of edges on abundances of target species was as likely to be positive as negative. Corridors were as likely to have no effect on antagonists or population synchrony as they were to increase those negative effects. We found 3 deficiencies in the literature. First, despite studies on how corridors affect predators, there are few studies of related consequences for prey population size and persistence. Second, properly designed studies of negative corridor effects are needed in natural corridors at scales larger than those achievable in experimental systems. Third, studies are needed to test more targeted hypotheses about when corridor-mediated effects on invasive species or disturbance may be negative for species of management concern. Overall, we found no overarching support for concerns that construction and maintenance of habitat corridors may result in unintended negative consequences. Negative edge effects may be mitigated by widening

  12. Small membranes under negative surface tension.

    PubMed

    Avital, Yotam Y; Farago, Oded

    2015-03-28

    We use computer simulations and a simple free energy model to study the response of a bilayer membrane to the application of a negative (compressive) mechanical tension. Such a tension destabilizes the long wavelength undulation modes of giant vesicles, but it can be sustained when small membranes and vesicles are considered. Our negative tension simulation results reveal two regimes-(i) a weak negative tension regime characterized by stretching-dominated elasticity and (ii) a strong negative tension regime featuring bending-dominated elastic behavior. This resembles the findings of the classic Evans and Rawicz micropipette aspiration experiment in giant unilamellar vesicles (GUVs) [E. Evans and W. Rawicz, Phys, Rev. Lett. 64, 2094 (1990)]. However, in GUVs the crossover between the two elasticity regimes occurs at a small positive surface tension, while in smaller membranes it takes place at a moderate negative tension. Another interesting observation concerning the response of a small membrane to negative surface tension is related to the relationship between the mechanical and fluctuation tensions, which are equal to each other for non-negative values. When the tension decreases to negative values, the fluctuation tension γ drops somewhat faster than the mechanical tension τ in the small negative tension regime, before it saturates (and becomes larger than τ) for large negative tensions. The bending modulus exhibits an "opposite" trend. It remains almost unchanged in the stretching-dominated elastic regime, and decreases in the bending-dominated regime. Both the amplitudes of the thermal height undulations and the projected area variations diverge at the onset of mechanical instability. PMID:25833604

  13. Small membranes under negative surface tension

    NASA Astrophysics Data System (ADS)

    Avital, Yotam Y.; Farago, Oded

    2015-03-01

    We use computer simulations and a simple free energy model to study the response of a bilayer membrane to the application of a negative (compressive) mechanical tension. Such a tension destabilizes the long wavelength undulation modes of giant vesicles, but it can be sustained when small membranes and vesicles are considered. Our negative tension simulation results reveal two regimes—(i) a weak negative tension regime characterized by stretching-dominated elasticity and (ii) a strong negative tension regime featuring bending-dominated elastic behavior. This resembles the findings of the classic Evans and Rawicz micropipette aspiration experiment in giant unilamellar vesicles (GUVs) [E. Evans and W. Rawicz, Phys, Rev. Lett. 64, 2094 (1990)]. However, in GUVs the crossover between the two elasticity regimes occurs at a small positive surface tension, while in smaller membranes it takes place at a moderate negative tension. Another interesting observation concerning the response of a small membrane to negative surface tension is related to the relationship between the mechanical and fluctuation tensions, which are equal to each other for non-negative values. When the tension decreases to negative values, the fluctuation tension γ drops somewhat faster than the mechanical tension τ in the small negative tension regime, before it saturates (and becomes larger than τ) for large negative tensions. The bending modulus exhibits an "opposite" trend. It remains almost unchanged in the stretching-dominated elastic regime, and decreases in the bending-dominated regime. Both the amplitudes of the thermal height undulations and the projected area variations diverge at the onset of mechanical instability.

  14. How do negative emotions impair self-control? A neural model of negative urgency.

    PubMed

    Chester, David S; Lynam, Donald R; Milich, Richard; Powell, David K; Andersen, Anders H; DeWall, C Nathan

    2016-05-15

    Self-control often fails when people experience negative emotions. Negative urgency represents the dispositional tendency to experience such self-control failure in response to negative affect. Neither the neural underpinnings of negative urgency nor the more general phenomenon of self-control failure in response to negative emotions are fully understood. Previous theorizing suggests that an insufficient, inhibitory response from the prefrontal cortex may be the culprit behind such self-control failure. However, we entertained an alternative hypothesis: negative emotions lead to self-control failure because they excessively tax inhibitory regions of the prefrontal cortex. Using fMRI, we compared the neural activity of people high in negative urgency with controls on an emotional, inhibitory Go/No-Go task. While experiencing negative (but not positive or neutral) emotions, participants high in negative urgency showed greater recruitment of inhibitory brain regions than controls. Suggesting a compensatory function, inhibitory accuracy among participants high in negative urgency was associated with greater prefrontal recruitment. Greater activity in the anterior insula on negatively-valenced, inhibitory trials predicted greater substance abuse one month and one year after the MRI scan among individuals high in negative urgency. These results suggest that, among people whose negative emotions often lead to self-control failure, excessive reactivity of the brain's regulatory resources may be the culprit. PMID:26892861

  15. Mathematicians, Attributional Complexity, and Gender

    NASA Astrophysics Data System (ADS)

    Stalder, Daniel R.

    Given indirect indications in sex role and soda! psychology research that mathematical-deductive reasoning may negatively relate to social acuity, Study 1 investigated whether mathematicians were less attributionally complex than nonmathematicians. Study 1 administered the Attributional Complexity Scale, a measure of social acuity, to female and male faculty members and graduate students in four Midwestern schools. Atlrihutional complexity (AC) is the ability and motivation to give complex explanations for behavior. Study 1 found a significant interaction between field and gender. Only among women did mathematicians score lower on AC. In addition, an established gender difference in AC (that women score higher than men) was present only among nonmathematicians. Studies 2 and 3 offered some preliminary support for the possibility that it is generally female students who score tow on AC who aspire to he mathematicians and for the underlying view that female students' perceived similarity to mathematicians can influence their vocational choices.

  16. Forman curvature for complex networks

    NASA Astrophysics Data System (ADS)

    Sreejith, R. P.; Mohanraj, Karthikeyan; Jost, Jürgen; Saucan, Emil; Samal, Areejit

    2016-06-01

    We adapt Forman’s discretization of Ricci curvature to the case of undirected networks, both weighted and unweighted, and investigate the measure in a variety of model and real-world networks. We find that most nodes and edges in model and real networks have a negative curvature. Furthermore, the distribution of Forman curvature of nodes and edges is narrow in random and small-world networks, while the distribution is broad in scale-free and real-world networks. In most networks, Forman curvature is found to display significant negative correlation with degree and centrality measures. However, Forman curvature is uncorrelated with clustering coefficient in most networks. Importantly, we find that both model and real networks are vulnerable to targeted deletion of nodes with highly negative Forman curvature. Our results suggest that Forman curvature can be employed to gain novel insights on the organization of complex networks.

  17. Negative HPV screening test predicts low cervical cancer risk better than negative Pap test

    Cancer.gov

    Based on a study that included more than 1 million women, investigators at NCI have determined that a negative test for HPV infection compared to a negative Pap test provides greater safety, or assurance, against future risk of cervical cancer.

  18. Information Filtering Based on Users' Negative Opinions

    NASA Astrophysics Data System (ADS)

    Guo, Qiang; Li, Yang; Liu, Jian-Guo

    2013-05-01

    The process of heat conduction (HC) has recently found application in the information filtering [Zhang et al., Phys. Rev. Lett.99, 154301 (2007)], which is of high diversity but low accuracy. The classical HC model predicts users' potential interested objects based on their interesting objects regardless to the negative opinions. In terms of the users' rating scores, we present an improved user-based HC (UHC) information model by taking into account users' positive and negative opinions. Firstly, the objects rated by users are divided into positive and negative categories, then the predicted interesting and dislike object lists are generated by the UHC model. Finally, the recommendation lists are constructed by filtering out the dislike objects from the interesting lists. By implementing the new model based on nine similarity measures, the experimental results for MovieLens and Netflix datasets show that the new model considering negative opinions could greatly enhance the accuracy, measured by the average ranking score, from 0.049 to 0.036 for Netflix and from 0.1025 to 0.0570 for Movielens dataset, reduced by 26.53% and 44.39%, respectively. Since users prefer to give positive ratings rather than negative ones, the negative opinions contain much more information than the positive ones, the negative opinions, therefore, are very important for understanding users' online collective behaviors and improving the performance of HC model.

  19. Complex Systems

    PubMed Central

    Goldberger, Ary L.

    2006-01-01

    Physiologic systems in health and disease display an extraordinary range of temporal behaviors and structural patterns that defy understanding based on linear constructs, reductionist strategies, and classical homeostasis. Application of concepts and computational tools derived from the contemporary study of complex systems, including nonlinear dynamics, fractals and “chaos theory,” is having an increasing impact on biology and medicine. This presentation provides a brief overview of an emerging area of biomedical research, including recent applications to cardiopulmonary medicine and chronic obstructive lung disease. PMID:16921107

  20. [Carney complex].

    PubMed

    Kacerovská, D; Michal, M; Síma, R; Grossmann, P; Kazakov, D V

    2011-10-01

    Carney complex is a clinically and genetically heterogeneous disease, with at least two genetic loci including the PRKAR1A gene located on chromosome 17 and the CNC2 locus mapped to chromosome 2. Clinically this syndrome is characterized by multiple myxomas occurring in different anatomic sites, mucocutaneous pigmentary lesions, and a variety of non-endocrine and endocrine tumors, often causing endocrine abnormalities, involving various organs. Knowledge of morphological findings in CNC patients with their typical locations is necessary to raise suspicion of this syndrome by pathologists. Confirmation of the diagnosis allows regular clinical check-ups and early treatment of these patients. PMID:22145222

  1. Negative temperatures and the definition of entropy

    NASA Astrophysics Data System (ADS)

    Swendsen, Robert H.; Wang, Jian-Sheng

    2016-07-01

    The concept of negative temperature has recently received renewed interest in the context of debates about the correct definition of the thermodynamic entropy in statistical mechanics. Several researchers have identified the thermodynamic entropy exclusively with the "volume entropy" suggested by Gibbs, and have further concluded that by this definition, negative temperatures violate the principles of thermodynamics. We disagree with these conclusions. We demonstrate that volume entropy is inconsistent with the postulates of thermodynamics for systems with non-monotonic energy densities, while a definition of entropy based on the probability distributions of macroscopic variables does satisfy the postulates of thermodynamics. Our results confirm that negative temperature is a valid extension of thermodynamics.

  2. The false-negative Meckel's scan

    SciTech Connect

    Wilton, G.; Froelich, J.W.

    1982-10-01

    A case is presented of a 17-month-old girl who underwent two Meckel's scans with /sup 99m/Tc pertechnetate. The initial study was interpreted as normal while a subsequent study five days later was definitely positive. Surgery immediately following the positive Meckel's scan demonstrated a Meckel's diverticulum containing gastric mucosa without evidence of active hemorrhage. This prompted a review of the literature in reference to false-negative Meckel's scans which revealed a wide variance in the reported incidence of false-negative examinations. Repeat scintigraphy in the face of a strong clinical suspicion after an initial normal study may decrease the indicence of false-negative imaging series.

  3. Negative Generalization and Symptoms of Anxiety Disorders

    PubMed Central

    Fulford, Daniel; Rosen, Rebecca K.; Johnson, Sheri L.; Carver, Charles S.

    2013-01-01

    The tendency to generalize from a single failure to one's entire self-worth is an important correlate and predictor of depression. Despite conceptual overlap between cognitive biases in anxiety and depression, little research has examined whether negative generalization relates to anxiety symptoms. We examined associations of negative generalization with symptoms of several anxiety disorders, above and beyond its association with lifetime symptoms of depression, among 248 undergraduates. After controlling for lifetime symptoms of major depression, negative generalization was significantly correlated with symptoms of each anxiety disorder tested, most notably generalized anxiety and social phobia. PMID:24340170

  4. Negative Poisson's ratio materials via isotropic interactions.

    PubMed

    Rechtsman, Mikael C; Stillinger, Frank H; Torquato, Salvatore

    2008-08-22

    We show that under tension a classical many-body system with only isotropic pair interactions in a crystalline state can, counterintuitively, have a negative Poisson's ratio, or auxetic behavior. We derive the conditions under which the triangular lattice in two dimensions and lattices with cubic symmetry in three dimensions exhibit a negative Poisson's ratio. In the former case, the simple Lennard-Jones potential can give rise to auxetic behavior. In the latter case, a negative Poisson's ratio can be exhibited even when the material is constrained to be elastically isotropic. PMID:18764632

  5. Negative Poisson's Ratio Materials via Isotropic Interactions

    NASA Astrophysics Data System (ADS)

    Rechtsman, Mikael C.; Stillinger, Frank H.; Torquato, Salvatore

    2008-08-01

    We show that under tension a classical many-body system with only isotropic pair interactions in a crystalline state can, counterintuitively, have a negative Poisson’s ratio, or auxetic behavior. We derive the conditions under which the triangular lattice in two dimensions and lattices with cubic symmetry in three dimensions exhibit a negative Poisson’s ratio. In the former case, the simple Lennard-Jones potential can give rise to auxetic behavior. In the latter case, a negative Poisson’s ratio can be exhibited even when the material is constrained to be elastically isotropic.

  6. Negative and positive cesium ion studies

    NASA Technical Reports Server (NTRS)

    Kuehn, D. G.; Sutliff, D. E.; Chanin, L. M.

    1978-01-01

    Mass spectrometric analyses have been performed on the positive and negative species from discharges in Cs, He-Cs, and He-H2-Cs mixtures. Sampling was conducted through the electrodes of normal glow discharges and from close-spaced heated-cathode conditions, which approximate a cesium thermionic converter. No negative Cs ions were observed for Cs pressures less than .01 torr. Identified species included Cs(+), Cs2(+), Cs(-), and what appeared to be multiply charged ions. Low-mass negative and positive ions attributed to H2 were observed when an He-H2 mixture was also present in the discharge region.

  7. Disentangling theorem and monogamy for entanglement negativity

    NASA Astrophysics Data System (ADS)

    He, Huan; Vidal, Guifre

    2015-01-01

    Entanglement negativity is a measure of mixed-state entanglement increasingly used to investigate and characterize emerging quantum many-body phenomena, including quantum criticality and topological order. We present two results for the entanglement negativity: a disentangling theorem, which allows the use of this entanglement measure as a means to detect whether a wave function of three subsystems A ,B , and C factorizes into a product state for parts A B1 and B2C ; and a monogamy relation conjecture based on entanglement negativity, which states that if A is very entangled with B , then A cannot be simultaneously very entangled also with C .

  8. The Negative Testing and Negative Generation Effects Are Eliminated by Delay

    ERIC Educational Resources Information Center

    Mulligan, Neil W.; Peterson, Daniel J.

    2015-01-01

    Although retrieval often enhances subsequent memory (the testing effect), a negative testing effect has recently been documented in which prior retrieval harms later recall compared with restudying. The negative testing effect was predicated on the negative generation effect and the item-specific-relational framework. The present experiments…

  9. Carney complex.

    PubMed

    Espiard, Stéphanie; Bertherat, Jérôme

    2013-01-01

    Carney complex is a rare, dominantly inherited multiple endocrine neoplasia syndrome, affecting endocrine glands as the adrenal cortex (causing Cushing's syndrome), the pituitary and the thyroid. It is associated with many other nonendocrine tumors, including cardiac myxomas, testicular tumors, melanotic schwannoma, breast myxomatosis, and abnormal pigmentation (lentiginosis) or myxomas of the skin. The gene located on the CNC1 locus was identified 12 years ago as the regulatory subunit 1A (R1A) of the protein kinase A (PRKAR1A) located at 17q22-24. Inactivating heterozygous germline mutations of PRKAR1A are observed in about two thirds of Carney complex patients with some genotype-phenotype correlation useful for follow-up and prognosis. More rarely, mutations of phosphodiesterase genes have been reported in patients presenting mainly with Cushing's syndrome. In vitro and in vivo studies help to understand how R1A inactivation leads to tumorigenesis. PRKAR1A appears to be a relatively weak tumorigenic signal which can cooperate with other signaling pathways and tumor suppressors. PMID:23652670

  10. Microwave gain medium with negative refractive index

    NASA Astrophysics Data System (ADS)

    Ye, Dexin; Chang, Kihun; Ran, Lixin; Xin, Hao

    2014-12-01

    Artificial effective media are attractive because of the fantastic applications they may enable, such as super lensing and electromagnetic invisibility. However, the inevitable loss due to their strongly dispersive nature is one of the fundamental challenges preventing such applications from becoming a reality. In this study, we demonstrate an effective gain medium based on negative resistance, to overcompensate the loss of a conventional passive metamaterial, meanwhile keeping its original negative-index property. Energy conservation-based theory, full-wave simulation and experimental measurement show that a fabricated sample consisting of conventional sub-wavelength building blocks with embedded microwave tunnel diodes exhibits a band-limited Lorentzian dispersion simultaneously with a negative refractive index and a net gain. Our work provides experimental evidence to the assertion that a stable net gain in negative-index gain medium is achievable, proposing a potential solution for the critical challenge current metamateiral technology faces in practical applications.

  11. Negative feedback system reduces pump oscillations

    NASA Technical Reports Server (NTRS)

    Rosenmann, W.

    1967-01-01

    External negative feedback system counteracts low frequency oscillations in rocket engine propellant pumps. The system uses a control piston to sense pump discharge fluid on one side and a gas pocket on the other.

  12. Negative priming in free recall reconsidered.

    PubMed

    Hanczakowski, Maciej; Beaman, C Philip; Jones, Dylan M

    2016-05-01

    Negative priming in free recall is the finding of impaired memory performance when previously ignored auditory distracters become targets of encoding and retrieval. This negative priming has been attributed to an aftereffect of deploying inhibitory mechanisms that serve to suppress auditory distraction and minimize interference with learning and retrieval of task-relevant information. In 6 experiments, we tested the inhibitory account of the effect of negative priming in free recall against alternative accounts. We found that ignoring auditory distracters is neither sufficient nor necessary to produce the effect of negative priming in free recall. Instead, the effect is more readily accounted for by a buildup of proactive interference occurring whenever 2 successively presented lists of words are drawn from the same semantic category. (PsycINFO Database Record PMID:26595066

  13. Cannabis use, schizotypy, and negative priming.

    PubMed

    Albertella, Lucy; Le Pelley, Mike E; Copeland, Jan

    2015-08-30

    The present study examined the effects of frequency of cannabis use, schizotypy, and age on cognitive control, as measured using a location-based negative priming task in a sample of 124 Australians aged 15-24 who had ever used cannabis. This study found that the schizotypy dimension of Impulsive Nonconformity had a significant effect on negative priming such that participants with higher scores on this dimension showed reduced negative priming. Also, higher levels of psychological distress were associated with greater negative priming. Finally, there was a significant age by cannabis use interaction indicating that younger, frequent users of cannabis may be more susceptible to its effects on cognitive control and perhaps at greater risk of developing a disorder on the psychosis dimension. PMID:26154815

  14. Metal [100] Nanowires with Negative Poisson's Ratio.

    PubMed

    Ho, Duc Tam; Kwon, Soon-Yong; Kim, Sung Youb

    2016-01-01

    When materials are under stretching, occurrence of lateral contraction of materials is commonly observed. This is because Poisson's ratio, the quantity describes the relationship between a lateral strain and applied strain, is positive for nearly all materials. There are some reported structures and materials having negative Poisson's ratio. However, most of them are at macroscale, and reentrant structures and rigid rotating units are the main mechanisms for their negative Poisson's ratio behavior. Here, with numerical and theoretical evidence, we show that metal [100] nanowires with asymmetric cross-sections such as rectangle or ellipse can exhibit negative Poisson's ratio behavior. Furthermore, the negative Poisson's ratio behavior can be further improved by introducing a hole inside the asymmetric nanowires. We show that the surface effect inducing the asymmetric stresses inside the nanowires is a main origin of the superior property. PMID:27282358

  15. Superconductive microstrip exhibiting negative differential resistivity

    DOEpatents

    Huebener, R.P.; Gallus, D.E.

    1975-10-28

    A device capable of exhibiting negative differential electrical resistivity over a range of values of current and voltage is formed by vapor- depositing a thin layer of a material capable of exhibiting superconductivity on an insulating substrate, establishing electrical connections at opposite ends of the deposited strip, and cooling the alloy into its superconducting range. The device will exhibit negative differential resistivity when biased in the current- induced resistive state.

  16. [Depressive symptoms and negative symptoms during schizophrenia].

    PubMed

    Dollfus, S; Langlois, S; Assouly-Besse, F; Petit, M

    1995-06-01

    Taking into account the wellknown frequency of depressive and extrapyramidal symptoms in schizophrenia and the rare studies about their evolution, several questions can be raised: How do these different symptoms move? Are there specific characters of each of them? First, stability of negative symptoms evaluated by the Scale for the Assessment of Negative Symptoms (SANS) was studied among 57 schizophrenic patients at admission and at discharge. The course of negative symptoms was compared to that of depressive MADRS (Montgomery et Asberg Depression Rating Scale) and akinetic symptoms (Extrapyramidal Symptom Rating Scale). All the subscores of the SANS decreased significantly but 4 items belonging to the affective flattening subscale and one item belonging to the alogia subscale did not vary significantly, showing the necessity of taking into account the individual items of the SANS rather than the subscale scores to evaluate the course of negative symptoms. Changes in all the SANS subscores except the alogia and anhedonia subscores were associated with variations in scores of other scales. Correlations between the changes of negative symptoms and the changes of depressive symptoms showed the necessity to do more specific scales, for example, scales for depression in schizophrenia. Langlois-Théry et al. (1994) evaluated among 53 schizophrenic patients stabilized with neuroleptic treatment, depressive symptomatology with Echelle de Ralentissement Dépressif (ERD, Widlöcher, 1983) and MADRS, negative symptomatology (Positive and Negative Syndrome Scale) and akinesia (ESRS), to determinate whether ERD composed of 3 subscores (motor, ideic and subjective) could be able to evaluate the depressive symptomatology, independently of the measures of negative and akinetic symptomatology.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7628337

  17. Entropy analysis of systems exhibiting negative probabilities

    NASA Astrophysics Data System (ADS)

    Tenreiro Machado, J. A.

    2016-07-01

    This paper addresses the concept of negative probability and its impact upon entropy. An analogy between the probability generating functions, in the scope of quasiprobability distributions, and the Grünwald-Letnikov definition of fractional derivatives, is explored. Two distinct cases producing negative probabilities are formulated and their distinct meaning clarified. Numerical calculations using the Shannon entropy characterize further the characteristics of the two limit cases.

  18. Negative mass bubbles in de Sitter spacetime

    NASA Astrophysics Data System (ADS)

    Mbarek, Saoussen; Paranjape, M. B.

    2014-11-01

    We study the possibility of the existence of negative mass bubbles within a de Sitter spacetime background with matter content corresponding to a perfect fluid. It is shown that there exist configurations of the perfect fluid that satisfy everywhere the dominant energy condition, the Einstein equations and the equations of hydrostatic equilibrium which asymptotically approach the exact solution of Schwarzschild—de Sitter spacetime with a negative mass.

  19. Waves in geomaterials exhibiting negative stiffness behaviour

    NASA Astrophysics Data System (ADS)

    Esin, Maxim; Dyskin, Arcady; Pasternak, Elena

    2016-04-01

    Negative stiffness denotes the type of material behaviour when the force applied to the body decreases the body's deformation increases. Some geomaterials, for instance, rocks, demonstrate behaviour of this type at certain loads: during the compression tests the loading curves exhibit descending branch (post-peak softening). One of the possible mechanisms of the negative stiffness appearance in geomaterials is rotation of non-spherical grains. It is important to emphasize that in this case the descending branch may be reversible given that the testing machine is stiff enough (in general case it means an importance of boundary conditions). Existence of geomaterials with a negative modulus associated with rotations may have significant importance. In particular, important is understanding of the wave propagation in such materials. We study the stability of geomaterials with negative stiffness inclusions and wave propagation in it using two approaches: Cosserat continuum and discrete mass-spring models. In both cases we consider the rotational degrees of freedom in addition to the conventional translational ones. We show that despite non positiveness of the energy the materials with negative stiffness elements can be stable if certain conditions are met. In the case of Cosserat continuum the Cosserat shear modulus (the modulus relating the non-symmetrical part of shear stress and internal rotations) is allowed to assume negative values as long as its value does not exceed the value of the standard (positive) shear modulus. In the case of discrete mass-spring systems (with translational and rotational springs) the concentration of negative stiffness springs and the absolute values of negative spring stiffness are limited. The critical concentration when the system loses stability and the amplitude of the oscillations tends to infinity is equal to 1/2 and 3/5 for two- and three-dimensional cases respectively.

  20. Classical gravity does not refract negatively.

    PubMed

    McCall, Martin W

    2007-03-01

    We appraise recent claims that classical gravitation can induce negative refraction of electromagnetic radiation in vacuum. By recasting the previous literature in covariant notation, we show that the criterion used hitherto for determining negative refraction in vacuum is inappropriate, and can even be satisfied by parametrized transformations in Minkowski spacetime. Using instead a covariantly acceptable definition, we find that in classical vacuum the power flux of a plane electromagnetic wave points in the direction of phase advance. PMID:17359145

  1. Negative Capacitance transients in a ferroelectric capacitor

    NASA Astrophysics Data System (ADS)

    Khan, Asif; Chatterjee, Korok; Wang, Brian; Drapcho, Steven; You, Long; Serrao, Claudy; Bakaul, Saidur; Ramesh, Ramamoorthy; Salahuddin, Sayeef

    2015-03-01

    The Boltzmann distribution of electrons poses a fundamental barrier to lowering energy dissipation in conventional electronics, often termed as Boltzmann Tyranny. Negative capacitance in ferroelectric materials, which stems from the stored energy of phase transition, could provide a solution, but a direct measurement of negative capacitance has so far been elusive. Here we demonstrate the negative differential capacitance in a thin, single crystalline ferroelectric film, by constructing a simple R-C network and monitoring the voltage dynamics across the ferroelectric capacitor6. When a voltage pulse is applied, the voltage across the ferroelectric capacitor is found to be decreasing with time-in exactly the opposite direction to which voltage for a regular capacitor should change. The results are analyzed on the basis of the Landau-Khalatnikov equation, which shows that as the ferroelectric polarization switches its direction, it passes through the unstable negative capacitance region resulting in the characteristic ``negative capacitance transients.'' Analysis of this ``inductance''-like behavior from a capacitor allows us to calculate the value of the negative capacitance directly and presents an unprecedented insight into the intrinsic energy profile of the ferroelectric material.

  2. Negative capacitance in multidomain ferroelectric superlattices.

    PubMed

    Zubko, Pavlo; Wojdeł, Jacek C; Hadjimichael, Marios; Fernandez-Pena, Stéphanie; Sené, Anaïs; Luk'yanchuk, Igor; Triscone, Jean-Marc; Íñiguez, Jorge

    2016-06-23

    The stability of spontaneous electrical polarization in ferroelectrics is fundamental to many of their current applications, which range from the simple electric cigarette lighter to non-volatile random access memories. Research on nanoscale ferroelectrics reveals that their behaviour is profoundly different from that in bulk ferroelectrics, which could lead to new phenomena with potential for future devices. As ferroelectrics become thinner, maintaining a stable polarization becomes increasingly challenging. On the other hand, intentionally destabilizing this polarization can cause the effective electric permittivity of a ferroelectric to become negative, enabling it to behave as a negative capacitance when integrated in a heterostructure. Negative capacitance has been proposed as a way of overcoming fundamental limitations on the power consumption of field-effect transistors. However, experimental demonstrations of this phenomenon remain contentious. The prevalent interpretations based on homogeneous polarization models are difficult to reconcile with the expected strong tendency for domain formation, but the effect of domains on negative capacitance has received little attention. Here we report negative capacitance in a model system of multidomain ferroelectric-dielectric superlattices across a wide range of temperatures, in both the ferroelectric and paraelectric phases. Using a phenomenological model, we show that domain-wall motion not only gives rise to negative permittivity, but can also enhance, rather than limit, its temperature range. Our first-principles-based atomistic simulations provide detailed microscopic insight into the origin of this phenomenon, identifying the dominant contribution of near-interface layers and paving the way for its future exploitation. PMID:27296225

  3. Groups of Negations on the Unit Square

    PubMed Central

    2014-01-01

    The main results are about the groups of the negations on the unit square, which is considered as a bilattice. It is proven that all the automorphisms on it form a group; the set, containing the monotonic isomorphisms and the strict negations of the first (or the second or the third) kind, with the operator “composition,” is a group G2 (or G3 or G4, correspondingly). All these four kinds of mappings form a group G5. And all the groups Gi, i = 2,3, 4 are normal subgroups of G5. Moreover, for G5, a generator set is given, which consists of all the involutive negations of the second kind and the standard negation of the first kind. As a subset of the unit square, the interval-valued set is also studied. Two groups are found: one group consists of all the isomorphisms on LI, and the other group contains all the isomorphisms and all the strict negations on LI, which keep the diagonal. Moreover, the former is a normal subgroup of the latter. And all the involutive negations on the interval-valued set form a generator set of the latter group. PMID:25197719

  4. [Pneumocystis pneumonia in HIV-negative adults].

    PubMed

    Rouyer, M; Stoclin, A; Blanc, F-X

    2015-12-01

    In HIV-negative adults, Pneumocystis jirovecii pneumonia can be observed when immunodeficiency is present, especially in case of drug-induced immune suppression (steroids, chemotherapy, transplantation). Clinical, radiological, and biological presentations are different in HIV-positive and HIV-negative individuals with different immunodeficiency profiles. In HIV-negative patients, dyspnea occurs more quickly (median duration of 5 days to get a diagnosis), diagnosis is more difficult because of less Pneumocystis in bronchoalveolar lavage, and mortality is higher than in HIV-positive individuals. Lung CT-scan typically shows diffuse ground glass opacities, but peri-bronchovascular condensations or ground glass opacities clearly limited by interlobular septa can also be observed. Lymphopenia is common but CD4+ T-cells count is rarely performed. HIV-negative patients with Pneumocystis pneumonia are co-infected with bacteria, viruses or fungi in about 30% cases. Bronchoalveolar lavage is often more neutrophilic than in HIV-positive individuals. PCR and β-D-glucan have good sensitivity but poor specificity to diagnose Pneumocystis pneumonia. Trimethoprim-sulfamethoxazole remains the first choice of treatment. Duration is 14 days in HIV-negative patients whereas it is typically of 21 days in HIV-positive individuals. Adjunctive corticosteroids are of beneficial effect in HIV-positive adult patients with substantial hypoxaemia but are not recommended in HIV-negative patients, as they could be deleterious in some individuals. PMID:26572261

  5. Negative capacitance in multidomain ferroelectric superlattices

    NASA Astrophysics Data System (ADS)

    Zubko, Pavlo; Wojdeł, Jacek C.; Hadjimichael, Marios; Fernandez-Pena, Stéphanie; Sené, Anaïs; Luk’Yanchuk, Igor; Triscone, Jean-Marc; Íñiguez, Jorge

    2016-06-01

    The stability of spontaneous electrical polarization in ferroelectrics is fundamental to many of their current applications, which range from the simple electric cigarette lighter to non-volatile random access memories. Research on nanoscale ferroelectrics reveals that their behaviour is profoundly different from that in bulk ferroelectrics, which could lead to new phenomena with potential for future devices. As ferroelectrics become thinner, maintaining a stable polarization becomes increasingly challenging. On the other hand, intentionally destabilizing this polarization can cause the effective electric permittivity of a ferroelectric to become negative, enabling it to behave as a negative capacitance when integrated in a heterostructure. Negative capacitance has been proposed as a way of overcoming fundamental limitations on the power consumption of field-effect transistors. However, experimental demonstrations of this phenomenon remain contentious. The prevalent interpretations based on homogeneous polarization models are difficult to reconcile with the expected strong tendency for domain formation, but the effect of domains on negative capacitance has received little attention. Here we report negative capacitance in a model system of multidomain ferroelectric–dielectric superlattices across a wide range of temperatures, in both the ferroelectric and paraelectric phases. Using a phenomenological model, we show that domain-wall motion not only gives rise to negative permittivity, but can also enhance, rather than limit, its temperature range. Our first-principles-based atomistic simulations provide detailed microscopic insight into the origin of this phenomenon, identifying the dominant contribution of near-interface layers and paving the way for its future exploitation.

  6. Detecting Negative Obstacles by Use of Radar

    NASA Technical Reports Server (NTRS)

    Mittskus, Anthony; Lux, James

    2006-01-01

    Robotic land vehicles would be equipped with small radar systems to detect negative obstacles, according to a proposal. The term "negative obstacles" denotes holes, ditches, and any other terrain features characterized by abrupt steep downslopes that could be hazardous for vehicles. Video cameras and other optically based obstacle-avoidance sensors now installed on some robotic vehicles cannot detect obstacles under adverse lighting conditions. Even under favorable lighting conditions, they cannot detect negative obstacles. A radar system according to the proposal would be of the frequency-modulation/ continuous-wave (FM/CW) type. It would be installed on a vehicle, facing forward, possibly with a downward slant of the main lobe(s) of the radar beam(s) (see figure). It would utilize one or more wavelength(s) of the order of centimeters. Because such wavelengths are comparable to the characteristic dimensions of terrain features associated with negative hazards, a significant amount of diffraction would occur at such features. In effect, the diffraction would afford a limited ability to see corners and to see around corners. Hence, the system might utilize diffraction to detect corners associated with negative obstacles. At the time of reporting the information for this article, preliminary analyses of diffraction at simple negative obstacles had been performed, but an explicit description of how the system would utilize diffraction was not available.

  7. Negative Evaluations of Negative Alcohol Consequences Lead to Subsequent Reductions in Alcohol Use

    PubMed Central

    Barnett, Nancy P.; Merrill, Jennifer E.; Kahler, Christopher W.; Colby, Suzanne M.

    2015-01-01

    Alcohol use during young adulthood may reflect a learning process whereby positive and negative alcohol-related experiences and interpretations of those experiences drive subsequent behavior. Understanding the effect of consequences and the evaluation of consequences could be informative for intervention approaches. Objective To examine the extent to which the number of positive and negative alcohol consequences experienced and the evaluation of those consequences predict subsequent alcohol use and consequences in college students. Method Students at three colleges (N = 679) completed biweekly web-based surveys on alcohol use, positive and negative consequences, and consequence evaluations for two academic years. Hierarchical linear modeling tested whether consequences and evaluations in a given week predicted changes in alcohol use and consequences at the next assessment. Moderation by gender and class year also were evaluated. Results Evaluating past-week negative consequences more negatively than one’s average resulted in decreases in alcohol use at the next assessment. More negative evaluation of negative consequences was followed in the subsequent observation by a higher number of positive consequences for females but not males. A higher number of positive consequences in a given week was followed by a higher number of both positive and negative consequences in the subsequent observation. Number of negative consequences experienced and evaluation of positive consequences had no effect on later behavior. Conclusions Salient negative consequences may drive naturalistic reductions in alcohol use, suggesting the possible efficacy of programs designed to increase the salience of the negative effects of alcohol. PMID:26168225

  8. Negative evaluations of negative alcohol consequences lead to subsequent reductions in alcohol use.

    PubMed

    Barnett, Nancy P; Merrill, Jennifer E; Kahler, Christopher W; Colby, Suzanne M

    2015-12-01

    Alcohol use during young adulthood may reflect a learning process whereby positive and negative alcohol-related experiences and interpretations of those experiences drive subsequent behavior. Understanding the effect of consequences and the evaluation of consequences could be informative for intervention approaches. The objective of this study was to examine the extent to which the number of positive and negative alcohol consequences experienced and the evaluation of those consequences predict subsequent alcohol use and consequences in college students. Students at 3 colleges (N = 679) completed biweekly web-based surveys on alcohol use, positive and negative consequences, and consequence evaluations for 2 academic years. Hierarchical linear modeling tested whether consequences and evaluations in a given week predicted changes in alcohol use and consequences at the next assessment. Moderation by gender and class year were also evaluated. Evaluating past-week negative consequences more negatively than one's average resulted in decreases in alcohol use at the next assessment. More negative evaluation of negative consequences was followed in the subsequent observation by a higher number of positive consequences for females but not for males. A higher number of positive consequences in a given week was followed by a higher number of both positive and negative consequences in the subsequent observation. Number of negative consequences experienced and evaluation of positive consequences had no effect on later behavior. Salient negative consequences may drive naturalistic reductions in alcohol use, suggesting the possible efficacy of programs designed to increase the salience of the negative effects of alcohol. PMID:26168225

  9. Sensitivity of negative subsequent memory and task-negative effects to age and associative memory performance.

    PubMed

    de Chastelaine, Marianne; Mattson, Julia T; Wang, Tracy H; Donley, Brian E; Rugg, Michael D

    2015-07-01

    The present fMRI experiment employed associative recognition to investigate the relationships between age and encoding-related negative subsequent memory effects and task-negative effects. Young, middle-aged and older adults (total n=136) were scanned while they made relational judgments on visually presented word pairs. In a later memory test, the participants made associative recognition judgments on studied, rearranged (items studied on different trials) and new pairs. Several regions, mostly localized to the default mode network, demonstrated negative subsequent memory effects in an across age-group analysis. All but one of these regions also demonstrated task-negative effects, although there was no correlation between the size of the respective effects. Whereas negative subsequent memory effects demonstrated a graded attenuation with age, task-negative effects declined markedly between the young and the middle-aged group, but showed no further reduction in the older group. Negative subsequent memory effects did not correlate with memory performance within any age group. By contrast, in the older group only, task-negative effects predicted later memory performance. The findings demonstrate that negative subsequent memory and task-negative effects depend on dissociable neural mechanisms and likely reflect distinct cognitive processes. The relationship between task-negative effects and memory performance in the older group might reflect the sensitivity of these effects to variations in amount of age-related neuropathology. This article is part of a Special Issue entitled SI: Memory. PMID:25264353

  10. Personality Moderates the Interaction between Positive and Negative Daily Events Predicting Negative Affect and Stress

    PubMed Central

    Longua, Julie; DeHart, Tracy; Tennen, Howard; Armeli, Stephen

    2009-01-01

    A 30-day diary study examined personality moderators (neuroticism and extraversion) of the interaction between positive and negative daily events predicting daily negative affect and night-time stress. Multilevel analyses revealed positive daily events buffered the effect of negative daily events on negative affect for individuals low in neuroticism and individuals high in extraversion, but not for individuals high in neuroticism or individuals low in extraversion. Positive daily events also buffered the effect of negative daily events on that night’s stress, but only for participants low in neuroticism. As such, this research linked today’s events to tonight’s stressfulness. This study advances our understanding of how neuroticism and extraversion influence within-person associations between positive and negative events predicting negative affect and stress. PMID:20161239

  11. Napping and the selective consolidation of negative aspects of scenes.

    PubMed

    Payne, Jessica D; Kensinger, Elizabeth A; Wamsley, Erin J; Spreng, R Nathan; Alger, Sara E; Gibler, Kyle; Schacter, Daniel L; Stickgold, Robert

    2015-04-01

    After information is encoded into memory, it undergoes an offline period of consolidation that occurs optimally during sleep. The consolidation process not only solidifies memories, but also selectively preserves aspects of experience that are emotionally salient and relevant for future use. Here, we provide evidence that an afternoon nap is sufficient to trigger preferential memory for emotional information contained in complex scenes. Selective memory for negative emotional information was enhanced after a nap compared with wakefulness in 2 control conditions designed to carefully address interference and time-of-day confounds. Although prior evidence has connected negative emotional memory formation to REM sleep physiology, we found that non-REM delta activity and the amount of slow wave sleep (SWS) in the nap were robustly related to the selective consolidation of negative information. These findings suggest that the mechanisms underlying memory consolidation benefits associated with napping and nighttime sleep are not always the same. Finally, we provide preliminary evidence that the magnitude of the emotional memory benefit conferred by sleep is equivalent following a nap and a full night of sleep, suggesting that selective emotional remembering can be economically achieved by taking a nap. PMID:25706830

  12. Acute Effects of Marijuana Smoking on Negative and Positive Affect

    PubMed Central

    Metrik, Jane; Kahler, Christopher W.; McGeary, John E.; Monti, Peter M.; Rohsenow, Damaris J.

    2013-01-01

    Human studies and animal experiments present a complex and often contradictory picture of the acute impact of marijuana on emotions. The few human studies specifically examining changes in negative affect find either increases or reductions following delta-9-tetrahydrocannabinol (THC) administration. In a 2 × 2, instructional set (told THC vs. told no THC) by drug administration (smoked marijuana with 2.8% THC vs. placebo) between-subjects design, we examined the pharmacologic effect of marijuana on physiological and subjective stimulation, subjective intoxication, and self-reported negative and positive affect with 114 weekly marijuana smokers. Individuals were first tested under a baseline/no smoking condition and again under experimental condition. Relative to placebo, THC significantly increased arousal and confusion/bewilderment. However, the direction of effect on anxiety varied depending on instructional set: Anxiety increased after THC for those told placebo but decreased among other participants. Furthermore, marijuana users who expected more impairment from marijuana displayed more anxiety after smoking active marijuana, whereas those who did not expect the impairment became less anxious after marijuana. Both pharmacologic and stimulus expectancy main effects significantly increased positive affect. Frequent marijuana users were less anxious after smoking as compared to less frequent smokers. These findings show that expectancy instructions and pharmacology play independent roles in effects of marijuana on negative affect. Further studies examining how other individual difference factors impact marijuana's effects on mood are needed. PMID:24319318

  13. Auxetic polyethylene: The effect of a negative Poisson's ratio on hardness

    SciTech Connect

    Alderson, K.L.; Pickles, A.P.; Neale, P.J.; Evans, K.E. . Dept. of Materials Science and Engineering)

    1994-07-01

    Recent papers have described a particular form of ultra high molecular weight polyethylene (UHMWPE) which possesses a large negative Poisson's ratio ([nu]) because of its complex microstructure. Classical elasticity theory predicts that this should lead to enhancements in certain mechanical properties and this paper examines one such property -- that of ball indentation resistance or hardness. The hardness of auxetic UHMWPE with a negative [nu], compression molded UHMWPE and a microporous form of UHMWPE with a positive [nu] was measured. It was found that the presence of a negative [nu] resulted in enhancements of the hardness by up to a factor of 2 over conventional UHMWPE.

  14. Class 3 semaphorins negatively regulate dermal lymphatic network formation

    PubMed Central

    Uchida, Yutaka; James, Jennifer M.; Suto, Fumikazu; Mukouyama, Yoh-suke

    2015-01-01

    ABSTRACT The development of a patterned lymphatic vascular network is essential for proper lymphatic functions during organ development and homeostasis. Here we report that class 3 semaphorins (SEMA3s), SEMA3F and SEMA3G negatively regulate lymphatic endothelial cell (LEC) growth and sprouting to control dermal lymphatic network formation. Neuropilin2 (NRP2) functions as a receptor for SEMA3F and SEMA3G, as well as vascular endothelial growth factor C (VEGFC). In culture, Both SEMA3F and SEMA3G inhibit VEGFC-mediated sprouting and proliferation of human dermal LECs. In the developing mouse skin, Sema3f is expressed in the epidermis and Sema3g expression is restricted to arteries, whereas their receptor Nrp2 is preferentially expressed by lymphatic vessels. Both Sema3f;Sema3g double mutants and Nrp2 mutants exhibit increased LEC growth in the skin. In contrast, Sema3f;Sema3g double mutants display increased lymphatic branching, while Nrp2 mutants exhibit reduced lymphatic branching. A targeted mutation in PlexinA1 or PlexinA2, signal transducers forming a receptor complex with NRP2 for SEMA3s, exhibits an increase in LEC growth and lymphatic branching as observed in Sema3f;Sema3g double mutants. Our results provide the first evidence that SEMA3F and SEMA3G function as a negative regulator for dermal lymphangiogenesis in vivo. The reciprocal phenotype in lymphatic branching between Sema3f;Sema3g double mutants and Nrp2 mutants suggest a complex NRP2 function that regulates LEC behavior both positively and negatively, through a binding with VEGFC or SEMA3s. PMID:26319580

  15. Class 3 semaphorins negatively regulate dermal lymphatic network formation.

    PubMed

    Uchida, Yutaka; James, Jennifer M; Suto, Fumikazu; Mukouyama, Yoh-Suke

    2015-01-01

    The development of a patterned lymphatic vascular network is essential for proper lymphatic functions during organ development and homeostasis. Here we report that class 3 semaphorins (SEMA3s), SEMA3F and SEMA3G negatively regulate lymphatic endothelial cell (LEC) growth and sprouting to control dermal lymphatic network formation. Neuropilin2 (NRP2) functions as a receptor for SEMA3F and SEMA3G, as well as vascular endothelial growth factor C (VEGFC). In culture, Both SEMA3F and SEMA3G inhibit VEGFC-mediated sprouting and proliferation of human dermal LECs. In the developing mouse skin, Sema3f is expressed in the epidermis and Sema3g expression is restricted to arteries, whereas their receptor Nrp2 is preferentially expressed by lymphatic vessels. Both Sema3f;Sema3g double mutants and Nrp2 mutants exhibit increased LEC growth in the skin. In contrast, Sema3f;Sema3g double mutants display increased lymphatic branching, while Nrp2 mutants exhibit reduced lymphatic branching. A targeted mutation in PlexinA1 or PlexinA2, signal transducers forming a receptor complex with NRP2 for SEMA3s, exhibits an increase in LEC growth and lymphatic branching as observed in Sema3f;Sema3g double mutants. Our results provide the first evidence that SEMA3F and SEMA3G function as a negative regulator for dermal lymphangiogenesis in vivo. The reciprocal phenotype in lymphatic branching between Sema3f;Sema3g double mutants and Nrp2 mutants suggest a complex NRP2 function that regulates LEC behavior both positively and negatively, through a binding with VEGFC or SEMA3s. PMID:26319580

  16. Histone Deacetylase 9 Is a Negative Regulator of Adipogenic Differentiation*

    PubMed Central

    Chatterjee, Tapan K.; Idelman, Gila; Blanco, Victor; Blomkalns, Andra L.; Piegore, Mark G.; Weintraub, Daniel S.; Kumar, Santosh; Rajsheker, Srinivas; Manka, David; Rudich, Steven M.; Tang, Yaoliang; Hui, David Y.; Bassel-Duby, Rhonda; Olson, Eric N.; Lingrel, Jerry B.; Ho, Shuk-Mei; Weintraub, Neal L.

    2011-01-01

    Differentiation of preadipocytes into mature adipocytes capable of efficiently storing lipids is an important regulatory mechanism in obesity. Here, we examined the involvement of histone deacetylases (HDACs) and histone acetyltransferases (HATs) in the regulation of adipogenesis. We find that among the various members of the HDAC and HAT families, only HDAC9 exhibited dramatic down-regulation preceding adipogenic differentiation. Preadipocytes from HDAC9 gene knock-out mice exhibited accelerated adipogenic differentiation, whereas HDAC9 overexpression in 3T3-L1 preadipocytes suppressed adipogenic differentiation, demonstrating its direct role as a negative regulator of adipogenesis. HDAC9 expression was higher in visceral as compared with subcutaneous preadipocytes, negatively correlating with their potential to undergo adipogenic differentiation in vitro. HDAC9 localized in the nucleus, and its negative regulation of adipogenesis segregates with the N-terminal nuclear targeting domain, whereas the C-terminal deacetylase domain is dispensable for this function. HDAC9 co-precipitates with USF1 and is recruited with USF1 at the E-box region of the C/EBPα gene promoter in preadipocytes. Upon induction of adipogenic differentiation, HDAC9 is down-regulated, leading to its dissociation from the USF1 complex, whereas p300 HAT is up-regulated to allow its association with USF1 and accumulation at the E-box site of the C/EBPα promoter in differentiated adipocytes. This reciprocal regulation of HDAC9 and p300 HAT in the USF1 complex is associated with increased C/EBPα expression, a master regulator of adipogenic differentiation. These findings provide new insights into mechanisms of adipogenic differentiation and document a critical regulatory role for HDAC9 in adipogenic differentiation through a deacetylase-independent mechanism. PMID:21680747

  17. GDC-0941 and Cisplatin in Treating Patients With Androgen Receptor-Negative Triple Negative Metastatic Breast Cancer

    ClinicalTrials.gov

    2015-08-17

    Estrogen Receptor Negative Breast Cancer; Human Epidermal Growth Factor 2 Negative Carcinoma of Breast; Triple Negative Breast Cancer; Recurrent Breast Cancer; Stage IV Breast Cancer; Triple-negative Breast Cancer

  18. Negatively-Biased Credulity and the Cultural Evolution of Beliefs

    PubMed Central

    Fessler, Daniel M. T.; Pisor, Anne C.; Navarrete, Carlos David

    2014-01-01

    The functions of cultural beliefs are often opaque to those who hold them. Accordingly, to benefit from cultural evolution’s ability to solve complex adaptive problems, learners must be credulous. However, credulity entails costs, including susceptibility to exploitation, and effort wasted due to false beliefs. One determinant of the optimal level of credulity is the ratio between the costs of two types of errors: erroneous incredulity (failing to believe information that is true) and erroneous credulity (believing information that is false). This ratio can be expected to be asymmetric when information concerns hazards, as the costs of erroneous incredulity will, on average, exceed the costs of erroneous credulity; no equivalent asymmetry characterizes information concerning benefits. Natural selection can therefore be expected to have crafted learners’ minds so as to be more credulous toward information concerning hazards. This negatively-biased credulity extends general negativity bias, the adaptive tendency for negative events to be more salient than positive events. Together, these biases constitute attractors that should shape cultural evolution via the aggregated effects of learners’ differential retention and transmission of information. In two studies in the U.S., we demonstrate the existence of negatively-biased credulity, and show that it is most pronounced in those who believe the world to be dangerous, individuals who may constitute important nodes in cultural transmission networks. We then document the predicted imbalance in cultural content using a sample of urban legends collected from the Internet and a sample of supernatural beliefs obtained from ethnographies of a representative collection of the world’s cultures, showing that beliefs about hazards predominate in both. PMID:24736596

  19. Learning in rich networks involves both positive and negative associations.

    PubMed

    Roembke, Tanja C; Wasserman, Edward A; McMurray, Bob

    2016-08-01

    Adaptive behaviors are believed to be shaped by both positive (the strengthening of correct associations) and negative (the pruning of incorrect associations or the building of inhibitory associations) forms of associative learning. However, there has been little direct documentation of how these basic processes participate in the learning of rich associative networks that support cognitive behaviors like categorization. Although negative associative learning is an important component of theories of development, it is not clear whether it involves acquiring specific (experience-dependent) content or represents a more general aspect of (experience-expectant) development. The authors thus trained pigeons on a complex many-to-many learning paradigm previously established as an analog to human word learning. Pigeons learned to map 16 objects onto 16 distinct report tokens; the authors manipulated the amount of negative associative learning that could occur by restricting which tokens were available as incorrect options. In testing, accuracy was lower on trials with foils that had not been presented with a target than on trials with previously experienced foils. Moreover, when the correct token was withheld, pigeons preferred foils novel to the target object over previously experienced foils. A second experiment replicated these results and further found that these effects only emerged after some positive associations had been acquired. Findings indicate that the learning of rich associative networks does not depend solely on positive associative learning, but also on negative associative learning; this conclusion has important implications for basic learning theories in both animals and humans, as well as for theories of development. (PsycINFO Database Record PMID:27336324

  20. Negatively-biased credulity and the cultural evolution of beliefs.

    PubMed

    Fessler, Daniel M T; Pisor, Anne C; Navarrete, Carlos David

    2014-01-01

    The functions of cultural beliefs are often opaque to those who hold them. Accordingly, to benefit from cultural evolution's ability to solve complex adaptive problems, learners must be credulous. However, credulity entails costs, including susceptibility to exploitation, and effort wasted due to false beliefs. One determinant of the optimal level of credulity is the ratio between the costs of two types of errors: erroneous incredulity (failing to believe information that is true) and erroneous credulity (believing information that is false). This ratio can be expected to be asymmetric when information concerns hazards, as the costs of erroneous incredulity will, on average, exceed the costs of erroneous credulity; no equivalent asymmetry characterizes information concerning benefits. Natural selection can therefore be expected to have crafted learners' minds so as to be more credulous toward information concerning hazards. This negatively-biased credulity extends general negativity bias, the adaptive tendency for negative events to be more salient than positive events. Together, these biases constitute attractors that should shape cultural evolution via the aggregated effects of learners' differential retention and transmission of information. In two studies in the U.S., we demonstrate the existence of negatively-biased credulity, and show that it is most pronounced in those who believe the world to be dangerous, individuals who may constitute important nodes in cultural transmission networks. We then document the predicted imbalance in cultural content using a sample of urban legends collected from the Internet and a sample of supernatural beliefs obtained from ethnographies of a representative collection of the world's cultures, showing that beliefs about hazards predominate in both. PMID:24736596

  1. Negative transfer problem in neural networks

    NASA Astrophysics Data System (ADS)

    Abunawass, Adel M.

    1992-07-01

    Harlow, 1949, observed that when human subjects were trained to perform simple discrimination tasks over a sequence of successive training sessions (trials), their performance improved as a function of the successive sessions. Harlow called this phenomena `learning-to- learn.' The subjects acquired knowledge and improved their ability to learn in future training sessions. It seems that previous training sessions contribute positively to the current one. Abunawass & Maki, 1989, observed that when a neural network (using the back-propagation model) is trained over successive sessions, the performance and learning ability of the network degrade as a function of the training sessions. In some cases this leads to a complete paralysis of the network. Abunawass & Maki called this phenomena the `negative transfer' problem, since previous training sessions contribute negatively to the current one. The effect of the negative transfer problem is in clear contradiction to that reported by Harlow on human subjects. Since the ability to model human cognition and learning is one of the most important goals (and claims) of neural networks, the negative transfer problem represents a clear limitation to this ability. This paper describes a new neural network sequential learning model known as Adaptive Memory Consolidation. In this model the network uses its past learning experience to enhance its future learning ability. Adaptive Memory Consolidation has led to the elimination and reversal of the effect of the negative transfer problem. Thus producing a `positive transfer' effect similar to Harlow's learning-to-learn phenomena.

  2. The generality of negative hierarchically restrictive behaviours.

    PubMed

    Brown, Jennie; Trafimow, David; Gregory, W Larry

    2005-03-01

    Previous research has shown that when an actor engages in a negative hierarchically restrictive behaviour, a strong correspondent trait attribution is made and this behaviour is expected to generalize across situations (Trafimow, 2001). This paper discusses three experiments that examined the effects of extreme situations and perceived morality of the actor on the way in which participants make trait attributions, and the extent to which those behaviours are expected to generalize to other situations. Findings from Experiments 1 and 2 indicate that even negative hierarchically restrictive behaviours do not always lead to strong correspondent inferences if the situation in which the initial behaviour was performed was sufficiently extreme. Experiment 3 served to support these findings and cleared up questions from the first two experiments. Findings supported the hypothesis that some situations inhibit negative trait attributions and behaviour generalizations. Furthermore, findings indicate that the perception of the morality of the actor determines whether or not a negative hierarchically restrictive behaviour will lead to a negative trait attribution and generalization. PMID:15901388

  3. Extracted current saturation in negative ion sources

    SciTech Connect

    Mochalskyy, S.; Lifschitz, A. F.; Minea, T.

    2012-06-01

    The extraction of negatively charged particles from a negative ion source is one of the crucial issues in the development of the neutral beam injector system for future experimental reactor ITER. Full 3D electrostatic particle-in-cell Monte Carlo collision code - ONIX [S. Mochalskyy et al., Nucl. Fusion 50, 105011 (2010)] - is used to simulate the hydrogen plasma behaviour and the extracted particle features in the vicinity of the plasma grid, both sides of the aperture. It is found that the contribution to the extracted negative ion current of ions born in the volume is small compared with that of ions created at the plasma grid walls. The parametric study with respect to the rate of negative ions released from the walls shows an optimum rate. Beyond this optimum, a double layer builds-up by the negative ion charge density close to the grid aperture surface reducing thus extraction probability, and therefore the extracted current. The effect of the extraction potential and magnetic field magnitudes on the extraction is also discussed. Results are in good agreement with available experimental data.

  4. Negative obstacle detection by thermal signature

    NASA Technical Reports Server (NTRS)

    Matthies, Larry; Rankin, A.

    2003-01-01

    Detecting negative obstacles (ditches, potholes, and other depressions) is one of the most difficult problems in perception for autonomous, off-road navigation. Past work has largely relied on range imagery, because that is based on the geometry of the obstacle, is largely insensitive to illumination variables, and because there have not been other reliable alternatives. However, the visible aspect of negative obstacles shrinks rapidly with range, making them impossible to detect in time to avoid them at high speed. To relive this problem, we show that the interiors of negative obstacles generally remain warmer than the surrounding terrain throughout the night, making thermal signature a stable property for night-time negative obstacle detection. Experimental results to date have achieved detection distances 45% greater by using thermal signature than by using range data alone. Thermal signature is the first known observable with potential to reveal a deep negative obstacle without actually seeing far into it. Modeling solar illumination has potential to extend the usefulness of thermal signature through daylight hours.

  5. [Mutual inhibition between positive and negative emotions].

    PubMed

    Shimokawa, A

    1994-02-01

    The purpose of this study is to examine the relationship between positive and negative emotions. In study 1, 62 emotional items were selected in order to measure subjective emotional experiences. In study 2, comics, photos and poems were randomly presented to 1,220 college students to induce emotion. Subjects were asked to rate their momentary emotional intensity on two set of 5-point scales (general emotional intensity scale and 62 specific emotional intensity scale). In analysis 1, positive correlations were suggested between general emotional intensity scale and some of the specific emotional intensity scales which were activated by stimuli. In analysis 2, 10 positive and 10 negative emotional items were extracted from 62 items by factor analysis. In analysis 3, 4 and 5, it became clear that the distribution of frequency of correlations of 10 positive x 10 negative items changed according to the general emotional intensity scale. That is, from low to moderate levels of GEIS, the two kinds of emotion had no or slightly positive correlation, but at high level they became to be negatively correlated. From the facts described above, it is concluded that positive and negative emotions is not always independent, but show mutual inhibition in case of high intensity level of one of each emotions. PMID:8201808

  6. Bringing in the negative reinforcements: the avoidance feedback-related negativity.

    PubMed

    Crowley, Michael J; Wu, Jia; Bailey, Christopher A; Mayes, Linda C

    2009-11-25

    The feedback-related negativity (FRN) is an event-related potential thought to reflect a reward prediction error, when an outcome is worse than expected. Behavior motivated by the avoidance of negative outcomes is sustained through negative reinforcement processes. Escaping or avoiding a negative outcome may be successful or not, resulting in an analogous situation to that which elicits the FRN. We observed that when expected avoidance of an aversive outcome fails to occur, there occurs a negative deflection in the frontocentral event-related potential at approximately 350 ms, but with a slow wave following. We suggest that the FRN may be considered an index of a broader class of reward-based learning that also includes avoiding negative outcomes as well as expecting positive ones. PMID:19829164

  7. Carrier heating and negative photoconductivity in graphene

    SciTech Connect

    Heyman, J. N.; Stein, J. D.; Kaminski, Z. S.; Banman, A. R.; Massari, A. M.; Robinson, J. T.

    2015-01-07

    We investigated negative photoconductivity in graphene using ultrafast terahertz techniques. Infrared transmission was used to determine the Fermi energy, carrier density, and mobility of p-type chemical vapor deposition graphene samples. Time-resolved terahertz photoconductivity measurements using a tunable mid-infrared pump probed these samples at photon energies between 0.35 eV and 1.55 eV, approximately one-half to three times the Fermi energy of the samples. Although interband optical transitions in graphene are blocked for pump photon energies less than twice the Fermi energy, we observe negative photoconductivity at all pump photon energies investigated, indicating that interband excitation is not required to observe this effect. Our results are consistent with a thermalized free-carrier population that cools by electron-phonon scattering, but are inconsistent with models of negative photoconductivity based on population inversion.

  8. Negative coupled inductors for polyphase choppers

    NASA Technical Reports Server (NTRS)

    Jamieson, Robert S. (Inventor)

    1984-01-01

    A technique for negatively coupling the outputs of polyphase choppers is disclosed, wherein the output inductance of each phase is divided into two windings, and each winding is negatively coupled to a corresponding winding of a neighboring phase. In a preferred embodiment for a three-phase chopper circuit, the output inductance of phase A is divided into windings 100 and 102, the output inductance of phase B is divided into windings 110 and 112, and the output inductance of phase C is divided into windings 120 and 122. Pairs of windings 100 and 110, 112 and 120, and 102 and 122 are respectively disposed in transformers arranged for negatively coupling the windings of each pair.

  9. Classical fluids of negative heat capacity

    SciTech Connect

    Landsberg, P.T.; Woodard, R.P.

    1992-06-01

    It is shown that new parameters X can be defined such that the heat capacity C{sub X} {equivalent_to} T({partial_derivative}S/{partial_derivative}T)X is negative, even when the canonical ensemble (i.e. at fixed T = ({partial_derivative}U/{partial_derivative}S) and Y {ne} X) is stable. As examples we treat black body radiation and general gas systems with nonsingular {kappa}{sub T}. For the case of a simple ideal gas we even exhibit an apparatus which enforces a constraint X(p,V) = const. that makes C{sub X} < 0. Since it is possible to invent constraints for which canonically stable systems have negative heat capacity we speculate that it may also be possible to infer the statistical mechanics of canonically unstable systems - for which even the traditional heat capacities are negative - by imposing constraints that stabilize the associated, inoncanonical ensembles.

  10. Classical fluids of negative heat capacity

    SciTech Connect

    Landsberg, P.T. . Faculty of Mathematical Studies); Woodard, R.P. . Dept. of Physics)

    1992-06-01

    It is shown that new parameters X can be defined such that the heat capacity C{sub X} {equivalent to} T({partial derivative}S/{partial derivative}T)X is negative, even when the canonical ensemble (i.e. at fixed T = ({partial derivative}U/{partial derivative}S) and Y {ne} X) is stable. As examples we treat black body radiation and general gas systems with nonsingular {kappa}{sub T}. For the case of a simple ideal gas we even exhibit an apparatus which enforces a constraint X(p,V) = const. that makes C{sub X} < 0. Since it is possible to invent constraints for which canonically stable systems have negative heat capacity we speculate that it may also be possible to infer the statistical mechanics of canonically unstable systems - for which even the traditional heat capacities are negative - by imposing constraints that stabilize the associated, inoncanonical ensembles.

  11. Cells containing solvated electron lithium negative electrodes

    NASA Astrophysics Data System (ADS)

    Uribe, Francisco A.; Semkow, Krystyna W.; Sammells, Anthony F.

    1989-12-01

    This paper presents results obtained on cells based on solvated electron lithium negative electrodes, which may have application in high-energy-density secondary or reserve battery systems. The approach uses Li initially dissolved in liquid ammonia to give a solvated electron lithium/ammonia solution. This liquid negative active material is protected from direct contact with the liquid nonaqueous electrolyte in the positive electrode compartment by a lithium-intercalated electronically conducting ceramic membrane possessing Li(x)WoO2 composition with x values between 0.1 and 1.0. Depending upon initial lithium activity in the negative electrode compartments, the experimental cell was found to possess an initial open-circuit potential between 2.1 and 2.5 V.

  12. A new bivariate negative binomial regression model

    NASA Astrophysics Data System (ADS)

    Faroughi, Pouya; Ismail, Noriszura

    2014-12-01

    This paper introduces a new form of bivariate negative binomial (BNB-1) regression which can be fitted to bivariate and correlated count data with covariates. The BNB regression discussed in this study can be fitted to bivariate and overdispersed count data with positive, zero or negative correlations. The joint p.m.f. of the BNB1 distribution is derived from the product of two negative binomial marginals with a multiplicative factor parameter. Several testing methods were used to check overdispersion and goodness-of-fit of the model. Application of BNB-1 regression is illustrated on Malaysian motor insurance dataset. The results indicated that BNB-1 regression has better fit than bivariate Poisson and BNB-2 models with regards to Akaike information criterion.

  13. FTOC-Based Analysis of Negative Selection.

    PubMed

    Cunningham, Cody A; Teixeiro, Emma; Daniels, Mark A

    2016-01-01

    Potentially harmful T cell precursors are removed from the conventional T cell pool by negative selection. This process can involve the induction of apoptosis, anergy, receptor editing or deviation into a regulatory T cell lineage. As such this process is essential for the health of an organism through its contribution to central and peripheral tolerance. While a great deal is known about the process, the precise mechanisms that regulate negative selection are not clear. Furthermore, the signals that distinguish the different forms of negative selection are not fully understood. Numerous models exist with the potential to address these questions in vitro and in vivo. This chapter describes methods of fetal thymic organ culture designed to analyze the signals that determine these unique cell fates. PMID:26294405

  14. Tunable negative Poisson's ratio in hydrogenated graphene.

    PubMed

    Jiang, Jin-Wu; Chang, Tienchong; Guo, Xingming

    2016-09-21

    We perform molecular dynamics simulations to investigate the effect of hydrogenation on the Poisson's ratio of graphene. It is found that the value of the Poisson's ratio of graphene can be effectively tuned from positive to negative by varying the percentage of hydrogenation. Specifically, the Poisson's ratio decreases with an increase in the percentage of hydrogenation, and reaches a minimum value of -0.04 when the percentage of hydrogenation is about 50%. The Poisson's ratio starts to increase upon a further increase of the percentage of hydrogenation. The appearance of a minimum negative Poisson's ratio in the hydrogenated graphene is attributed to the suppression of the hydrogenation-induced ripples during the stretching of graphene. Our results demonstrate that hydrogenation is a valuable approach for tuning the Poisson's ratio from positive to negative in graphene. PMID:27536878

  15. A multimodal analysis of personal negativity.

    PubMed

    Furr, R M; Funder, D C

    1998-06-01

    This study examined how unhappiness and self-dissatisfaction are related to behavior, self-perception, social reputation, and the way one is treated by others. Varying in personal negativity (PN)--a composite of unhappiness, dissatisfaction with life, low self-esteem, and nonclinical depression--146 undergraduates (82 women and 64 men) engaged in 3 interactions. Participants' behavior and the behavior of their interaction partners was coded from videotapes. Personality ratings were obtained from participants and from 2 close acquaintances. PN was closely associated with maladaptive social interactions, negative behavioral responses by others, and a negative social reputation and self-image. Although women more clearly expressed PN behaviorally, men and women showed generally similar patterns of correlates. These results suggest that even subclinical levels of unhappiness and self-dissatisfaction may have important consequences. PMID:9654761

  16. [Carney complex].

    PubMed

    Losada Grande, Eladio José; Al Kassam Martínez, Daniel; González Boillos, Margarita

    2011-01-01

    Carney complex (CNC) is an autosomal dominantly inherited syndrome characterized by spotty skin pigmentation, cardiac and cutaneous myxoma, and endocrine overactivity. Skin pigmentation includes lentigines and blue nevi. Myxomas may occur in breast, skin and heart. Cardiac myxomas may be multiple and occur in any cardiac chamber, and are more prone to recurrence. The most common endocrine gland manifestation is an ACTH-independent Cushing's syndrome due to primary pigmented nodular adrenocortical disease (PPNAD). PPNAD may occur isolated, with no other signs of CNC. Pituitary and thyroid glands and gonads are also involved. The PRKAR1A gene, located in 17 q22-24, encodes type 1A regulatory subunit of protein kinase A. Inactivating germline mutations of this gene are found in 70% of patients with CNC. PRKAR1A is a key component of the c-AMP signaling pathway that has been implicated in endocrine tumorigenesis. Many different mutations have been reported in the PRKAR1A gene. In almost all cases the sequence change was predicted to lead to a premature stop codon and the resultant mutant mRNA was subject to nonsense-mediated mRNA decay. There is no clear genotype-phenotype correlation in patients with CNC. Genetic analysis should be performed in all CNC index cases. All affected patients should be monitored for clinical signs of CNC at least once a year. Genetic diagnosis allows for more effective preparation of more appropriate and effective therapeutic strategies and genetic counseling for patients and gene carriers, and to avoid unnecessary tests to relatives not carrying the gene. PMID:21536508

  17. Negative Electron Affinity Mechanism for Diamond Surfaces

    NASA Technical Reports Server (NTRS)

    Krainsky, I. L.; Asnin, V. M.

    1998-01-01

    The energy distribution of the secondary electrons for chemical vacuum deposited diamond films with Negative Electron Affinity (NEA) was investigated. It was found that while for completely hydrogenated diamond surfaces the negative electron affinity peak in the energy spectrum of the secondary electrons is present for any energy of the primary electrons, for partially hydrogenated diamond surfaces there is a critical energy above which the peak is present in the spectrum. This critical energy increases sharply when hydrogen coverage of the diamond surface diminishes. This effect was explained by the change of the NEA from the true type for the completely hydrogenated surface to the effective type for the partially hydrogenated surfaces.

  18. Above-threshold ionization of negative hydrogen

    NASA Astrophysics Data System (ADS)

    Nikolopoulos, L. A. A.; Lambropoulos, P.

    1997-10-01

    We present detailed calculations for two-and three-photon above-threshold ionization of the negative hydrogen ion. In addition to calculated values for partial wave amplitudes and phase shifts pertaining to recent experimental results [Xin Miao Zhao et al., Phys. Rev. Lett. 78, 1656 (1997)], we also address the question of the asymmetry of photoelectron angular distributions in ionization under elliptically polarized radiation, which has been studied experimentally in other negative ions [C. Blondel and C. Delsart, Laser Phys. 3, 3 (1993); Nucl. Instrum. Methods Phys. Res. B 79, 156 (1993); F. Dulieu, C. Blondel, and C. Delsart, J. Phys. B 28, 3861 (1995)].

  19. Negative refraction using Raman transitions and chirality

    SciTech Connect

    Sikes, D. E.; Yavuz, D. D.

    2011-11-15

    We present a scheme that achieves negative refraction with low absorption in far-off resonant atomic systems. The scheme utilizes Raman resonances and does not require the simultaneous presence of an electric-dipole transition and a magnetic-dipole transition near the same wavelength. We show that two interfering Raman tran-sitions coupled to a magnetic-dipole transition can achieve a negative index of refraction with low absorption through magnetoelectric cross-coupling. We confirm the validity of the analytical results with exact numerical simulations of the density matrix. We also discuss possible experimental implementations of the scheme in rare-earth metal atomic systems.

  20. Negative refraction using Raman transitions and chirality

    NASA Astrophysics Data System (ADS)

    Sikes, D. E.; Yavuz, D. D.

    2011-11-01

    We present a scheme that achieves negative refraction with low absorption in far-off resonant atomic systems. The scheme utilizes Raman resonances and does not require the simultaneous presence of an electric-dipole transition and a magnetic-dipole transition near the same wavelength. We show that two interfering Raman tran-sitions coupled to a magnetic-dipole transition can achieve a negative index of refraction with low absorption through magnetoelectric cross-coupling. We confirm the validity of the analytical results with exact numerical simulations of the density matrix. We also discuss possible experimental implementations of the scheme in rare-earth metal atomic systems.

  1. Real and imaginary negative binomial states

    NASA Astrophysics Data System (ADS)

    Liao, Jing; Wang, Xiaoguang; Wu, Ling-An; Pan, Shao-Hua

    2001-10-01

    The real and imaginary negative binomial states formed by a superposition of the negative binomial states are introduced. The sub-Poissonian statistics, Wigner function and squeezing properties of the real and imaginary states are studied in detail. The oscillatory character of the photon distribution due to the quantum interference between the two components is shown. Moreover, we find that these states are real and imaginary nonlinear Schrödinger cat states and give the corresponding ladder operator formalisms. We also discuss how to generate these general real quantum superposition states based on the intensity-dependent Jaynes-Cummings model.

  2. Negative Coulomb Drag in Double Bilayer Graphene.

    PubMed

    Li, J I A; Taniguchi, T; Watanabe, K; Hone, J; Levchenko, A; Dean, C R

    2016-07-22

    We report on an experimental measurement of Coulomb drag in a double quantum well structure consisting of bilayer-bilayer graphene, separated by few layer hexagonal boron nitride. At low temperatures and intermediate densities, a novel negative drag response with an inverse sign is observed, distinct from the momentum and energy drag mechanisms previously reported in double monolayer graphene. By varying the device aspect ratio, the negative drag component is suppressed and a response consistent with pure momentum drag is recovered. In the momentum drag dominated regime, excellent quantitative agreement with the density and temperature dependence predicted for double bilayer graphene is found. PMID:27494491

  3. Negative photoconductivity of InAs nanowires.

    PubMed

    Han, Yuxiang; Zheng, Xiao; Fu, Mengqi; Pan, Dong; Li, Xing; Guo, Yao; Zhao, Jianhua; Chen, Qing

    2016-01-14

    Negative photoconductivity is observed in InAs nanowires (NWs) without a surface defective layer. The negative photoconductivity is strongly dependent on the wavelength and intensity of the light, and is also sensitive to the environmental atmosphere. Two kinds of mechanisms are discerned to work together. One is related to gas adsorption, which is photodesorption of water molecules and photo-assisted chemisorption of O2 molecules. The other one can be attributed to the photogating effect introduced by the native oxide layer outside the NWs. PMID:26631367

  4. Negative electrodes for lithium cells and batteries

    DOEpatents

    Vaughey, John T.; Fransson, Linda M.; Thackeray, Michael M.

    2005-02-15

    A negative electrode is disclosed for a non-aqueous electrochemical cell. The electrode has an intermetallic compound as its basic structural unit with the formula M.sub.2 M' in which M and M' are selected from two or more metal elements including Si, and the M.sub.2 M' structure is a Cu.sub.2 Sb-type structure. Preferably M is Cu, Mn and/or Li, and M' is Sb. Also disclosed is a non-aqueous electrochemical cell having a negative electrode of the type described, an electrolyte and a positive electrode. A plurality of cells may be arranged to form a battery.

  5. GPM Solar Array Gravity Negated Deployment Testing

    NASA Technical Reports Server (NTRS)

    Penn, Jonathan; Johnson, Chris; Lewis, Jesse; Dear, Trevin; Stewart, Alphonso

    2014-01-01

    NASA Goddard Space Flight Center (GSFC) successfully developed a g-negation support system for use on the solar arrays of the Global Precipitation Measurement (GPM) Satellite. This system provides full deployment capability at the subsystem and observatory levels. In addition, the system provides capability for deployed configuration first mode frequency verification testing. The system consists of air pads, a support structure, an air supply, and support tables. The g-negation support system was used to support all deployment activities for flight solar array deployment testing.

  6. Examining the latent structure of negative symptoms: is there a distinct subtype of negative symptom schizophrenia?

    PubMed

    Blanchard, Jack J; Horan, William P; Collins, Lindsay M

    2005-09-15

    Negative symptoms have emerged as a replicable factor of symptomatology within schizophrenia. Although rating scales provide assessments along dimensions of severity, categorization into a negative symptom subtype is typically conducted. A categorical view of negative symptoms is best reflected in the proposal that enduring, primary negative symptoms, or deficit symptoms, reflect a distinct subtype of schizophrenia . Despite an accumulation of findings that support a categorical conceptualization, the data are also consistent with a dimensional-only model where negative symptom subtypologies simply reflect an extreme on a continuum of severity. Using taxometric statistical methods , the present study examined whether a taxonic, or latent class, model best describes negative symptoms in a sample of 238 schizophrenia patients. In order to obtain more stable estimates of symptoms, ratings on the Scale for the Assessment of Negative Symptoms [Andreasen, N.C., 1982. Negative symptoms in schizophrenia: Definition and reliability. Arch. Gen. Psychiatry 39, 784-788.] were averaged across two assessments over a 6-month period. Two taxometric methods, maximum covariance analysis (MAXCOV) and mean above minus below a cut (MAMBAC) identified a latent class or taxon with a base rate of approximately 28-36%. Members of the negative symptom taxon differed from the nontaxon class in that taxon members were more likely to be male and demonstrated poorer social functioning. Taxon and nontaxon schizophrenia patients did not differ in psychotic or affective symptoms. The findings converge to provide support for a categorical view of negative symptoms. Further research is required to replicate the present taxonic findings and to examine characteristics (including possible etiological factors) associated with this negative symptom taxon. PMID:15916881

  7. Burton-Roberts on Presupposition and Negation.

    ERIC Educational Resources Information Center

    Seuren, Pieter A. M.

    1990-01-01

    A critical analysis explores the strictly logical aspects and pragmatic claims of a presupposition and negation theory (Burton-Roberts, 1989). Other clearly relevant facts, not previously considered, are used to show that the theory preempted empirical issues on invalid a priori grounds. (23 references) (Author/CB)

  8. Toward laser cooling of negative lanthanum

    NASA Astrophysics Data System (ADS)

    Jordan, Elena; Cerchiari, Giovanni; Erlewein, Stefan; Kellerbauer, Alban; UNIC Team

    2016-05-01

    Anion laser cooling holds the potential to allow the production of ultracold ensembles of any negatively charged species by sympathetic cooling. It is a promising technique for cooling of antiprotons to a few mK and could clear the way for precision measurements on cold antihydrogen. Laser cooling of negative ions has never been achieved, since most species have no bound-bound electric dipole transitions. Negative lanthanum (La-) is one of the few anions with multiple electric dipole transitions. The bound-bound transition from the 3F2e ground state to the 3D1o excited state in La- has been proposed theoretically as a candidate for laser cooling. The potential laser cooling transition was identified using laser photodetachment spectroscopy and its excitation energy was measured. We have studied the aforementioned transition in a beam of La anions by high-resolution laser photodetachment spectroscopy. Seven of the nine expected hyperfine structure transitions have been resolved and the transition cross sections have been estimated from experimental observations. It was found that presently La- is the most promising candidate among the atomic anions. We plan to demonstrate the first direct laser cooling of negative ions in a linear radio frequency trap. We gratefully acknowledge support from the European Research Council (ERC).

  9. Revisiting the gram-negative lipoprotein paradigm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The processing of lipoproteins (lpps) in Gram-negative bacteria is generally considered to be an essential pathway. Mature lipoproteins in these bacteria are triacylated, with the final fatty acid addition performed by Lnt, an apolipoprotein n-acyltransferase. The mature lipoproteins are then sorted...

  10. Attribution of Negative Intention in Williams Syndrome

    ERIC Educational Resources Information Center

    Godbee, Kali; Porter, Melanie A.

    2013-01-01

    People with Williams syndrome (WS) are said to have sociable and extremely trusting personalities, approaching strangers without hesitation. This study investigated whether people with WS are less likely than controls to attribute negative intent to others when interpreting a series of ambiguous pictures. This may, at least partially, explain…

  11. Negative running can prevent eternal inflation

    SciTech Connect

    Kinney, William H.; Freese, Katherine E-mail: ktfreese@umich.edu

    2015-01-01

    Current data from the Planck satellite and the BICEP2 telescope favor, at around the 2 σ level, negative running of the spectral index of curvature perturbations from inflation. We show that for negative running α < 0, the curvature perturbation amplitude has a maximum on scales larger than our current horizon size. A condition for the absence of eternal inflation is that the curvature perturbation amplitude always remain below unity on superhorizon scales. For current bounds on n{sub S} from Planck, this corresponds to an upper bound of the running α < −9 × 10{sup −5}, so that even tiny running of the scalar spectral index is sufficient to prevent eternal inflation from occurring, as long as the running remains negative on scales outside the horizon. In single-field inflation models, negative running is associated with a finite duration of inflation: we show that eternal inflation may not occur even in cases where inflation lasts as long as 10{sup 4} e-folds.

  12. The Contrast Theory of Negative Input.

    ERIC Educational Resources Information Center

    Saxton, Matthew

    1997-01-01

    Presents an alternative definition of negative evidence, based on the idea that the unique discourse structure created in the juxtaposition of child error and adult correct form can reveal the child in contrast or conflict between the two forms. Findings reveal that children reproduced the correct irregular model more often and persisted with…

  13. Overcoming Graduate Students' Negative Perceptions of Statistics

    ERIC Educational Resources Information Center

    Lalayants, Marina

    2012-01-01

    Although there has been some attention in the literature to such issues as students' attitudes toward statistics, instructors are still constantly faced with the challenge to engage students; understand their perceptions, motivations, and interests; and deal with their reluctance and negative attitudes toward the field of statistics. The purpose…

  14. The Negative "Aspects" of Children's Writing.

    ERIC Educational Resources Information Center

    Gale, Irma F.; Boisvert, Louis

    This study of the negative side of children's writing utilized an experimental group and a control group equalized according to sex and the results of the language sub-tests of the Stanford Achievement Tests. Students wrote two 1,000 word composition samples, one during the first month of the study and one during the ninth month. The purposes of…

  15. Color infrared film as a negative material

    USGS Publications Warehouse

    Pease, Robert W.

    1970-01-01

    Original problems encountered in endeavors to use color infraredfilm as a negative material have been overcome by a simple modification in processing. This makes more feasible the production of infrared color prints for field use and yields an infrared counterpart to Aero-Neg.

  16. Estimating the Probability of Negative Events

    ERIC Educational Resources Information Center

    Harris, Adam J. L.; Corner, Adam; Hahn, Ulrike

    2009-01-01

    How well we are attuned to the statistics of our environment is a fundamental question in understanding human behaviour. It seems particularly important to be able to provide accurate assessments of the probability with which negative events occur so as to guide rational choice of preventative actions. One question that arises here is whether or…

  17. Comprehension of action negation involves inhibitory simulation.

    PubMed

    Foroni, Francesco; Semin, Gün R

    2013-01-01

    Previous research suggests that action language is comprehended by activating the motor system. We report a study, investigating a critical question in this research field: do negative sentences activate the motor system? Participants were exposed to sentences in the affirmation and negation forms while the zygomatic muscle activity on the left side of the face was continuously measured (Electromyography technique: EMG). Sentences were descriptions of emotional expressions that mapped either directly upon the zygomatic muscle (e.g., "I am smiling") or did not (e.g., "I am frowning"). Reading sentences involving the negation of the activity of a specific muscle (zygomatic major-"I am not smiling") is shown to lead to the inhibition of this muscle. Reading sentences involving the affirmative form instead ("I am smiling") leads to the activation of zygomatic mucle. In contrast, sentences describing an activity that is irrelevant to the zygomatic muscle (e.g., "I am frowning" or "I am not frowning") produce no muscle activity. These results extend the range of simulation models to negation and by implication to an abstract domain. We discuss how this research contributes to the grounding of abstract and concrete concepts. PMID:23754996

  18. The negative affect hypothesis of noise sensitivity.

    PubMed

    Shepherd, Daniel; Heinonen-Guzejev, Marja; Heikkilä, Kauko; Dirks, Kim N; Hautus, Michael J; Welch, David; McBride, David

    2015-05-01

    Some studies indicate that noise sensitivity is explained by negative affect, a dispositional tendency to negatively evaluate situations and the self. Individuals high in such traits may report a greater sensitivity to other sensory stimuli, such as smell, bright light and pain. However, research investigating the relationship between noise sensitivity and sensitivity to stimuli associated with other sensory modalities has not always supported the notion of a common underlying trait, such as negative affect, driving them. Additionally, other explanations of noise sensitivity based on cognitive processes have existed in the clinical literature for over 50 years. Here, we report on secondary analyses of pre-existing laboratory (n = 74) and epidemiological (n = 1005) data focusing on the relationship between noise sensitivity to and annoyance with a variety of olfactory-related stimuli. In the first study a correlational design examined the relationships between noise sensitivity, noise annoyance, and perceptual ratings of 16 odors. The second study sought differences between mean noise and air pollution annoyance scores across noise sensitivity categories. Results from both analyses failed to support the notion that, by itself, negative affectivity explains sensitivity to noise. PMID:25993104

  19. Negative mechanistic reasoning in medical intervention assessment.

    PubMed

    Jerkert, Jesper

    2015-12-01

    Traditionally, mechanistic reasoning has been assigned a negligible role in standard EBM (evidence-based medicine) literature, although some recent authors have argued for an upgrade. Even so, the mechanistic reasoning that has received attention has almost exclusively been positive--both in an epistemic sense of claiming that there is a mechanistic chain and in a health-related sense of there being claimed benefits for the patient. Negative mechanistic reasoning has been neglected, both in the epistemic and in the health-related sense. I distinguish three main types of negative mechanistic reasoning and subsume them under a new definition of mechanistic reasoning in the context of assessing medical interventions. This definition is wider than a previous suggestion in the literature. Each negative type corresponds to a range of evidential strengths, and it is argued that there are differences with respect to typical evidential strengths. The variety of negative mechanistic reasoning should be acknowledged in EBM, and it presents a serious challenge to proponents of so-called medical hierarchies of evidence. PMID:26597869

  20. A Hidden Case of Negative Amortization.

    ERIC Educational Resources Information Center

    Waits, Bert K.; Demana, Franklin

    1990-01-01

    The rule of 78 is used by banks and loan companies to compute the amounts due when installment loans are paid early. Describes an unexpected case of negative amortization when the rule is applied. Presents an actual problem and discusses the case. (YP)

  1. Negative Impacts of High-Stakes Testing

    ERIC Educational Resources Information Center

    Minarechová, Michaela

    2012-01-01

    High-stakes testing is not a new phenomenon in education. It has become part of the education system in many countries. These tests affect the school systems, teachers, students, politicians and parents, whether that is in a positive or negative sense. High-stakes testing is associated with concepts such as a school's accountability, funding…

  2. Hydrogen Plasmas for Negative Ion Production

    SciTech Connect

    Pagano, D.; Gorse, C.; Capitelli, M.

    2005-05-16

    We have improved a zero-dimensional model, built to simulate the operating conditions in the excitation ('driver') region of a multicusp ion source optimized for negative ion production of great interest in thermonuclear applications. The new approach to couple heavy particle and electron kinetics is discussed.

  3. Negative Refraction experiments in Photonic Crystal prisms

    NASA Astrophysics Data System (ADS)

    Vodo, Plarenta; Parimi, Patanjali. V.; Lu, Wentao. T.; di Gennaro, Emiliano; Sridhar, Srinivas

    2004-03-01

    We have experimentally demonstrated negative refraction in metallic photonic crystal (PC) prisms [1]. The refracted fields in the parallel plate waveguide (PPW) are measured by an automated dipole antenna, which scans the desired area, while the free space (FS) measurements, performed in a anechoic chamber, are measured by a rectangular X-band horn that swings in an arc in far field area. Both TE and TM excitation modes are used in FS experiments. Numerical calculations of the band structure and equi-frequency surface simulations are used to determine frequency regions of negative refraction of the triangular lattice PC. Angle of refraction determined by theoretical simulations and experimental results, are in exceptional good agreement, yielding the negative refraction index. FS and PPW refraction experimental results agree remarkably with simulations. 1. "Negative Refraction and Left-handed electromagnetism in Microwave Photonic Crystals", P.V Parimi, W.T Lu, P.Vodo J. Sokoloff and S.Sridhar, cond-mat/0306109 (2003)

  4. Negative Electrode For An Alkaline Cell

    DOEpatents

    Coco, Isabelle; Cocciantelli, Jean-Michel; Villenave, Jean-Jacques

    1998-07-14

    The present invention concerns a negative electrode for an alkaline cell, comprising a current collector supporting a paste containing an electrochemically active material and a binder, characterized in that said binder is a polymer containing hydrophilic and hydrophobic groups, said polymer being selected from an acrylic homopolymer, copolymer and terpolymer, an unsaturated organic acid copolymer and an unsaturated acid anhydride copolymer.

  5. Is Higher Education a Negative Product?

    ERIC Educational Resources Information Center

    Widrick, Stanley; Fram, Eugene

    1984-01-01

    Evidence from a Rochester, New York study of high school and college students suggests that, for major student segments, higher education can be a negative product. Students may attend college to get away from family, procrastinate from job-seeking, locate a spouse, or meet higher job and salary requirements. Marketing implications are discussed.…

  6. Pull Out Negativity by Its Roots.

    ERIC Educational Resources Information Center

    DuFour, Rick; Burnette, Becky

    2002-01-01

    Principals are well-positioned to cultivate their schools' cultures. They must remain vigilant in rooting out the beginnings of negative culture, including such teacher attitudes and behaviors as not feeling responsible for student learning, preferring to work alone, wanting to protect their territory, and focusing on activity rather than results.…

  7. L2 Negation Constructions at Work

    ERIC Educational Resources Information Center

    Eskildsen, Soren W.

    2012-01-01

    This article explores the usage- and exemplar-based roots of second language (L2) negation construction learning. Based on two longitudinal case studies involving two adult L2 English learners and a corpus of 63 three-hour sessions of recorded classroom interactions, the study shows that L2 learning follows the predictions of usage-based models of…

  8. Further Conceptualization of Explanation in Negative Messages.

    ERIC Educational Resources Information Center

    Limaye, Mohan R.

    1997-01-01

    Makes two suggestions for presentation in the classroom and in textbooks of business communication regarding explanation in negative messages: (1) providing a reasonable explanation is the sender's moral obligation, and receiving such explanation is a natural right of the target; and (2) explanation should be presented on two levels: general and…

  9. Challenging Negative Perceptions of Black Teachers

    ERIC Educational Resources Information Center

    Milner, H. Richard

    2012-01-01

    In this article, the author focuses on a case study of an African-American teacher's perceptions about teaching and instructional practices in an urban middle school, Bridge Middle School. He provides a counter to some negative conceptions of Black teachers in general through a focus on this teacher: the way she thinks about her roles and…

  10. Negative Capacitance in a Ferroelectric Capacitor

    NASA Astrophysics Data System (ADS)

    Khan, Asif; Chatterjee, Korok; Wang, Brian; Drapcho, Steven; You, Long; Serrao, Claudy; Bakaul, Saidur; Ramesh, Ramamoorthy; Salahuddin, Sayeef; UC Berkeley Team

    The Boltzmann distribution of electrons poses a fundamental barrier to lowering energy dissipation in conventional electronics, often termed as Boltzmann Tyranny. Negative capacitance in ferroelectric materials, which stems from the stored energy of phase transition, could provide a solution, but a direct measurement of negative capacitance has so far been elusive. Here we demonstrate the negative differential capacitance in an epitaxial ferroelectric film, by constructing a simple R-C network and monitoring the voltage dynamics across the ferroelectric capacitor. When a voltage pulse is applied, the voltage across the ferroelectric capacitor is found to be decreasing with time-in exactly the opposite direction to which voltage for a regular capacitor should change. The results are analyzed on the basis of the Landau-Khalatnikov equation, which shows that as the ferroelectric polarization switches its direction, it passes through the unstable negative capacitance region. Analysis of this behavior from a capacitor presents an unprecedented insight into the intrinsic energy profile of the ferroelectric material.

  11. The Negative Affect Hypothesis of Noise Sensitivity

    PubMed Central

    Shepherd, Daniel; Heinonen-Guzejev, Marja; Heikkilä, Kauko; Dirks, Kim N.; Hautus, Michael J.; Welch, David; McBride, David

    2015-01-01

    Some studies indicate that noise sensitivity is explained by negative affect, a dispositional tendency to negatively evaluate situations and the self. Individuals high in such traits may report a greater sensitivity to other sensory stimuli, such as smell, bright light and pain. However, research investigating the relationship between noise sensitivity and sensitivity to stimuli associated with other sensory modalities has not always supported the notion of a common underlying trait, such as negative affect, driving them. Additionally, other explanations of noise sensitivity based on cognitive processes have existed in the clinical literature for over 50 years. Here, we report on secondary analyses of pre-existing laboratory (n = 74) and epidemiological (n = 1005) data focusing on the relationship between noise sensitivity to and annoyance with a variety of olfactory-related stimuli. In the first study a correlational design examined the relationships between noise sensitivity, noise annoyance, and perceptual ratings of 16 odors. The second study sought differences between mean noise and air pollution annoyance scores across noise sensitivity categories. Results from both analyses failed to support the notion that, by itself, negative affectivity explains sensitivity to noise. PMID:25993104

  12. Intonational Prominence on Negatives in English.

    ERIC Educational Resources Information Center

    Yaeger-Dror, Malcah L.

    1985-01-01

    Describes a study done to determine which intonational parameters are most important to the meaning being conveyed within different social settings. Defines the factors that appear to influence the use of pitch and/or intensity prominence on negative words. Found that, in many situations, interactional rules take precedence over linguistic rules.…

  13. Quantum Rigidity of Negatively Curved Manifolds

    NASA Astrophysics Data System (ADS)

    Chirvasitu, Alexandru

    2016-05-01

    We show that an isometric action of a compact quantum group on the underlying geodesic metric space of a compact connected Riemannian manifold ( M, g) with strictly negative curvature is automatically classical, in the sense that it factors through the action of the isometry group of ( M, g). This partially answers a question by D. Goswami.

  14. Error-Related Psychophysiology and Negative Affect

    ERIC Educational Resources Information Center

    Hajcak, G.; McDonald, N.; Simons, R.F.

    2004-01-01

    The error-related negativity (ERN/Ne) and error positivity (Pe) have been associated with error detection and response monitoring. More recently, heart rate (HR) and skin conductance (SC) have also been shown to be sensitive to the internal detection of errors. An enhanced ERN has consistently been observed in anxious subjects and there is some…

  15. Stress and Coping Activity: Reframing Negative Thoughts

    ERIC Educational Resources Information Center

    Hughes, Jamie S.; Gourley, Mary K.; Madson, Laura; Le Blanc, Katya

    2011-01-01

    Stress management and coping techniques are not only relevant in many psychology courses but also personally relevant for undergraduate students. In this article, the authors describe an activity designed to provide students with practice evaluating and challenging negative self-talk. Students responded to scenarios individually, were paired with…

  16. Negative Effects from Psychological Treatments: A Perspective

    ERIC Educational Resources Information Center

    Barlow, David H.

    2010-01-01

    The author offers a 40-year perspective on the observation and study of negative effects from psychotherapy or psychological treatments. This perspective is placed in the context of the enormous progress in refining methodologies for psychotherapy research over that period of time, resulting in the clear demonstration of positive effects from…

  17. Clausal Architecture and Sentential Negation in Slavic

    ERIC Educational Resources Information Center

    Tsurska, Olena Anatoliyivna

    2010-01-01

    This study presents a comparative analysis of the clausal architecture and sentential negation in East (Russian, Ukrainian, and Belarusian), West, Polish, Czech, Slovak, and Upper and Lower Sorbian), and South (Bulgarian, Macedonian, Bosnian/Croatian/Serbian, and Slovenian) languages. Using the Minimalist Program, I analyze the syntactic structure…

  18. Negative Bodily Self in Suicide Attempters

    ERIC Educational Resources Information Center

    Orbach, Israel; Gilboa-Schechtman, Eva; Sheffer, Amir; Meged, Sorin; Har-Even, Dov; Stein, Daniel

    2006-01-01

    In the present study we investigated the relationship between suicidal behavior and aspects of bodily perception and parental care. Measures of bodily perception included measures of tactile sensitivity, body attitudes, and body experiences. Measures of parental care included parental bonding, negative and positive touch, and early maltreatment.…

  19. When Depressive Cognitions Reflect Negative Realities.

    ERIC Educational Resources Information Center

    Krantz, Susan E.

    The cognitive model of depression postulates that the depressed individual's cognitions are not only negative, but erroneous and impervious to information from the environment. However, the valence of that information ultimately determines whether those cognitions are impervious or merely receptive. The actual life circumstances of the depressed…

  20. Proactive and Retroactive Effects of Negative Suggestion

    ERIC Educational Resources Information Center

    Brown, Alan S.; Brown, Christine M.; Mosbacher, Joy L.; Dryden, W. Erich

    2006-01-01

    The negative effects of false information presented either prior to (proactive interference; PI) or following (retroactive interference; RI) true information was examined with word definitions (Experiment 1) and trivia facts (Experiment 2). Participants were explicitly aware of which information was true and false when shown, and true-false…

  1. Negativity Bias in Attribution of External Agency

    ERIC Educational Resources Information Center

    Morewedge, Carey K.

    2009-01-01

    This research investigated whether people are more likely to attribute events to external agents when events are negative rather than neutral or positive. Participants more often believed that ultimatum game partners were humans rather than computers when the partners offered unusually unfavorable divisions than unusually favorable divisions…

  2. Is Cross-Race Mentoring a Negative?

    ERIC Educational Resources Information Center

    Dolan, Thomas G.

    2007-01-01

    The author discusses cross-race mentoring and examines whether this is necessarily a negative. Here, he presents the opinions of one African-American female Ph.D., two Hispanic female Ph.D.s, and one Hispanic male graduate student, who offer varied perspectives. Ten points are presented: (1) 1. Cross-race mentoring requires extra sensitivity; (2)…

  3. Suicidal Fantasies and Positive/Negative Effects.

    ERIC Educational Resources Information Center

    Fouts, Gregory; Norrie, Janice

    This study attempted to provide some initial normative data to help professionals and researchers to distinguish between playful and stimulating suicidal fantasies as opposed to serious and compulsive thoughts and behaviours characterized by negative affects. It is argued that the former is a natural consequence of cognitive development, the entry…

  4. [Psychopathological aspects of negative symptoms in schizophrenia].

    PubMed

    Cermolacce, M; Belzeaux, R; Pringuey, D; Adida, M; Azorin, J-M

    2015-12-01

    During the past ten years, research on schizophrenia has witnessed a clear emphasis on studies based on negative symptoms. This interest can be explained in terms of diagnosis, specific treatment, functional prognosis and outcome issues. However, main current approaches consider negative symptoms from an operationalist view, which implies objective and atheoretical descriptions of clinical criteria, observed from a third person perspective. And the understanding of negative symptoms in schizophrenia, still a crucial issue of mental health, remains only partial. From a different perspective, psychopathology - and notably psychiatric phenomenology -, can provide a conceptual and clinical framework, taking into account subjective experience (first person perspective), based on a global understanding of the clinical situation lived by patients with schizophrenia. In the present review, we give a brief survey on the historical aspects of the description of negative symptoms. Then, we introduce the clinical contributions raised by clinical phenomenology. We principally develop Minkowski's notion of loss of vital contact, and Blankenburg's notion of loss of natural evidence. Then we highlight the current debates which are discussed and explored in contemporary psychopathology. In conclusion, we discuss the possible articulation between objective and subjective approaches, in order to better understand pauci-symptomatic forms of schizophrenia. PMID:26776395

  5. Positive Effects of Talking about the Negative: Family Narratives of Negative Experiences and Preadolescents' Perceived Competence

    ERIC Educational Resources Information Center

    Marin, Kelly A.; Bohanek, Jennifer G.; Fivush, Robyn

    2008-01-01

    Family narratives about the past are an important context for the socialization of emotion, but relations between expression of negative emotion and children's emerging competence are conflicting. In this study, 24 middle-class two-parent families narrated a shared negative experience together and we examined the process (initiations and…

  6. Revisiting the Gram-Negative Lipoprotein Paradigm

    PubMed Central

    LoVullo, Eric D.; Wright, Lori F.; Isabella, Vincent; Huntley, Jason F.

    2015-01-01

    ABSTRACT The processing of lipoproteins (Lpps) in Gram-negative bacteria is generally considered an essential pathway. Mature lipoproteins in these bacteria are triacylated, with the final fatty acid addition performed by Lnt, an apolipoprotein N-acyltransferase. The mature lipoproteins are then sorted by the Lol system, with most Lpps inserted into the outer membrane (OM). We demonstrate here that the lnt gene is not essential to the Gram-negative pathogen Francisella tularensis subsp. tularensis strain Schu or to the live vaccine strain LVS. An LVS Δlnt mutant has a small-colony phenotype on sucrose medium and increased susceptibility to globomycin and rifampin. We provide data indicating that the OM lipoprotein Tul4A (LpnA) is diacylated but that it, and its paralog Tul4B (LpnB), still sort to the OM in the Δlnt mutant. We present a model in which the Lol sorting pathway of Francisella has a modified ABC transporter system that is capable of recognizing and sorting both triacylated and diacylated lipoproteins, and we show that this modified system is present in many other Gram-negative bacteria. We examined this model using Neisseria gonorrhoeae, which has the same Lol architecture as that of Francisella, and found that the lnt gene is not essential in this organism. This work suggests that Gram-negative bacteria fall into two groups, one in which full lipoprotein processing is essential and one in which the final acylation step is not essential, potentially due to the ability of the Lol sorting pathway in these bacteria to sort immature apolipoproteins to the OM. IMPORTANCE This paper describes the novel finding that the final stage in lipoprotein processing (normally considered an essential process) is not required by Francisella tularensis or Neisseria gonorrhoeae. The paper provides a potential reason for this and shows that it may be widespread in other Gram-negative bacteria. PMID:25755189

  7. How to target estrogen receptor-negative breast cancer?

    PubMed

    Rochefort, H; Glondu, M; Sahla, M E; Platet, N; Garcia, M

    2003-06-01

    Estrogen receptor (ER)-positive breast cancers generally have a better prognosis and are often responsive to anti-estrogen therapy, which is the first example of a successful therapy targeted on a specific protein, the ER. Unfortunately ER-negative breast cancers are more aggressive and unresponsive to anti-estrogens. Other targeted therapies are thus urgently needed, based on breast cancer oncogene inhibition or suppressor gene activation as far as molecular studies have demonstrated the alteration of expression, or structure of these genes in human breast cancer. Using the MDA-MB.231 human breast cancer cell line as a model of ER-negative breast cancers, we are investigating two of these approaches in our laboratory. Our first approach was to transfect the ER or various ER-deleted variants into an ER-negative cell line in an attempt to recover anti-estrogen responsiveness. The unliganded receptor, and surprisingly estradiol, were both found to inhibit tumor growth and invasiveness in vitro and in vivo. The mechanisms of these inhibitions in ER-negative cancer cells are being studied, in an attempt to target the ER sequence responsible for such inhibition in these cancer cells. Another strategy is trying to inhibit the activity or expression of an oncogene specifically overexpressed in most breast cancers. This approach was recently shown by others to be efficient in breast cancer therapy with HER2-Neu oncogene amplification using Herceptin. Without excluding other molecular putative targets, we have focused our research on cathepsin D as a potential target, since it is often overexpressed in aggressive human breast cancers, including ER-negative tumors, and rarely associated with HER2-Neu amplification. Our first results obtained in vitro on cell lines and in vivo in tumor xenografts in nude mice, illustrate that the mode of action of cathepsin D in breast cancer is useful to guide the development of these therapies. In the past 20 years we have learned that the

  8. The Costs of Today's Jobs: Job Characteristics and Organizational Supports as Antecedents of Negative Spillover

    ERIC Educational Resources Information Center

    Grotto, Angela R.; Lyness, Karen S.

    2010-01-01

    This study examined job characteristics and organizational supports as antecedents of negative work-to-nonwork spillover for 1178 U.S. employees. Based on hierarchical regression analyses of 2002 National Study of the Changing Workforce data and O*NET data, job demands (requirements to work at home beyond scheduled hours, job complexity, time and…

  9. Identifying the Impact of Negative Feedback and Learners' Responses on ESL Question Development

    ERIC Educational Resources Information Center

    McDonough, Kim

    2005-01-01

    Swain's (1985, 1995, 2000) output hypothesis states that language production is facilitative of second language (L2) learning. An important component of the output hypothesis involves "pushing" learners to produce appropriate, accurate, and complex language (Swain, 1993), which may occur when interlocutors provide learners with negative feedback…

  10. The Dark Side of Friendship: Questions about Negative Interactions between Friends.

    ERIC Educational Resources Information Center

    Berndt, Thomas J.

    Alluding to the difficulty in explaining the two opposing powers, the "dark side" and the Force, in the Star Wars movies, this paper focuses on the complex combination of negative and positive interactions among children who are best friends. Presented in question-answer format, the paper discusses research findings and needs related to two seldom…

  11. Leadership Values, Trust and Negative Capability: Managing the Uncertainties of Future English Higher Education

    ERIC Educational Resources Information Center

    Jameson, Jill

    2012-01-01

    The complex leadership attribute of "negative capability" in managing uncertainty and engendering trust may be amongst the qualities enabling institutions to cope with multiple recent government policy challenges affecting English higher education, including significant increases in student fees. Research findings are reported on changes in…

  12. A cardiovascular system model for lower-body negative pressure response

    NASA Technical Reports Server (NTRS)

    Mitchell, B. A., Jr.; Giese, R. P.

    1971-01-01

    Mathematical models used to study complex physiological control systems are discussed. Efforts were made to modify a model of the cardiovascular system for use in studying lower body negative pressure. A computer program was written which allows orderly, straightforward expansion to include exercise, metabolism (thermal stress), respiration, and other body functions.

  13. Blufensin1 Negatively Impacts Basal Defense in Response to Barley Powdery Mildew

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plants have evolved complex regulatory mechanisms to control the defense response against microbial attack. Both temporal and spatial gene expression are tightly regulated in response to pathogen ingress, modulating both positive and negative control of defense. BLUFENSIN1 (BLN1), a small peptide ...

  14. Is the negative glow plasma of a direct current glow discharge negatively charged?

    NASA Astrophysics Data System (ADS)

    Bogdanov, E. A.; Demidov, V. I.; Kudryavtsev, A. A.; Saifutdinov, A. I.

    2015-02-01

    A classic problem in gas discharge physics is discussed: what is the sign of charge density in the negative glow region of a glow discharge? It is shown that traditional interpretations in text-books on gas discharge physics that states a negative charge of the negative glow plasma are based on analogies with a simple one-dimensional model of discharge. Because the real glow discharges with a positive column are always two-dimensional, the transversal (radial) term in divergence with the electric field can provide a non-monotonic axial profile of charge density in the plasma, while maintaining a positive sign. The numerical calculation of glow discharge is presented, showing a positive space charge in the negative glow under conditions, where a one-dimensional model of the discharge would predict a negative space charge.

  15. Is the negative glow plasma of a direct current glow discharge negatively charged?

    SciTech Connect

    Bogdanov, E. A.; Saifutdinov, A. I.; Demidov, V. I.; Kudryavtsev, A. A.

    2015-02-15

    A classic problem in gas discharge physics is discussed: what is the sign of charge density in the negative glow region of a glow discharge? It is shown that traditional interpretations in text-books on gas discharge physics that states a negative charge of the negative glow plasma are based on analogies with a simple one-dimensional model of discharge. Because the real glow discharges with a positive column are always two-dimensional, the transversal (radial) term in divergence with the electric field can provide a non-monotonic axial profile of charge density in the plasma, while maintaining a positive sign. The numerical calculation of glow discharge is presented, showing a positive space charge in the negative glow under conditions, where a one-dimensional model of the discharge would predict a negative space charge.

  16. The positives of negative emotions: willingness to express negative emotions promotes relationships.

    PubMed

    Graham, Steven M; Huang, Julie Y; Clark, Margaret S; Helgeson, Vicki S

    2008-03-01

    Four studies support the hypothesis that expressing negative emotion is associated with positive relationship outcomes, including elicitation of support, building of new close relationships, and heightening of intimacy in the closest of those relationships. In Study 1, participants read vignettes in which another person was experiencing a negative emotion. Participants reported they would provide more help when the person chose to express the negative emotion. In Study 2, participants watched a confederate preparing for a speech. Participants provided more help to her when she expressed nervousness. In Study 3, self-reports of willingness to express negative emotions predicted having more friends, controlling for demographic variables and extraversion. In Study 4, self-reports of willingness to express negative emotion measured prior to arrival at college predicted formation of more relationships, greater intimacy in the closest of those relationships, and greater received support from roommates across participants' first semester of college. PMID:18272807

  17. Developments in Plant Negative-Strand RNA Virus Reverse Genetics.

    PubMed

    Jackson, Andrew O; Li, Zhenghe

    2016-08-01

    Twenty years ago, breakthroughs for reverse genetics analyses of negative-strand RNA (NSR) viruses were achieved by devising conditions for generation of infectious viruses in susceptible cells. Recombinant strategies have subsequently been engineered for members of all vertebrate NSR virus families, and research arising from these advances has profoundly increased understanding of infection cycles, pathogenesis, and complexities of host interactions of animal NSR viruses. These strategies also permitted development of many applications, including attenuated vaccines and delivery vehicles for therapeutic and biotechnology proteins. However, for a variety of reasons, it was difficult to devise procedures for reverse genetics analyses of plant NSR viruses. In this review, we discuss advances that have circumvented these problems and resulted in construction of a recombinant system for Sonchus yellow net nucleorhabdovirus. We also discuss possible extensions to other plant NSR viruses as well as the applications that may emanate from recombinant analyses of these pathogens. PMID:27359368

  18. Mismatch Negativity with Visual-only and Audiovisual Speech

    PubMed Central

    Ponton, Curtis W.; Bernstein, Lynne E.; Auer, Edward T.

    2009-01-01

    The functional organization of cortical speech processing is thought to be hierarchical, increasing in complexity and proceeding from primary sensory areas centrifugally. The current study used the mismatch negativity (MMN) obtained with electrophysiology (EEG) to investigate the early latency period of visual speech processing under both visual-only (VO) and audiovisual (AV) conditions. Current density reconstruction (CDR) methods were used to model the cortical MMN generator locations. MMNs were obtained with VO and AV speech stimuli at early latencies (approximately 82-87 ms peak in time waveforms relative to the acoustic onset) and in regions of the right lateral temporal and parietal cortices. Latencies were consistent with bottom-up processing of the visible stimuli. We suggest that a visual pathway extracts phonetic cues from visible speech, and that previously reported effects of AV speech in classical early auditory areas, given later reported latencies, could be attributable to modulatory feedback from visual phonetic processing. PMID:19404730

  19. Chondroitin-4-sulfation negatively regulates axonal guidance and growth

    PubMed Central

    Wang, Hang; Katagiri, Yasuhiro; McCann, Thomas E.; Unsworth, Edward; Goldsmith, Paul; Yu, Zu-Xi; Tan, Fei; Santiago, Lizzie; Mills, Edward M.; Wang, Yu; Symes, Aviva J.; Geller, Herbert M.

    2008-01-01

    Summary Glycosaminoglycan (GAG) side chains endow extracellular matrix proteoglycans with diversity and complexity based upon the length, composition, and charge distribution of the polysaccharide chain. Using cultured primary neurons, we show that specific sulfation in the GAG chains of chondroitin sulfate (CS) mediates neuronal guidance cues and axonal growth inhibition. Chondroitin-4-sulfate (CS-A), but not chondroitin-6-sulfate (CS-C), exhibits a strong negative guidance cue to mouse cerebellar granule neurons. Enzymatic and gene-based manipulations of 4-sulfation in the GAG side chains alter their ability to direct growing axons. Furthermore, 4-sulfated CS GAG chains are rapidly and significantly increased in regions that do not support axonal regeneration proximal to spinal cord lesions in mice. Thus, our findings provide the evidence showing that specific sulfation along the carbohydrate backbone carries instructions to regulate neuronal function. PMID:18768934

  20. Simplified negative pressure wound therapy with instillation: advances and recommendations.

    PubMed

    Gabriel, Allen; Rauen, Brigitta

    2014-01-01

    Positive results have been demonstrated with the adjunctive use of negative pressure wound therapy (NPWT) and instillation (NPWTi) for stalled and/or complex wounds. With these combined therapies, instillation assists in wound bed preparation and cleansing by loosening soluble material in the wound bed, which can be subsequently removed during the NPWT phase. Previously reported instilled solutions have included saline, topical cleansers, and antiseptics. Recently, a new NPWTi system (V.A.C. VeraFlo™ Therapy, KCI USA, Inc., San Antonio, TX) has been introduced that includes automated, volumetrically controlled delivery of solutions and new foam dressings specifically designed for use with NPWTi. We present the latest NPWTi technologies, provide nursing recommendations for patient management, and conclude with a case study. PMID:24887351

  1. Negative Differential Conductivity in an Interacting Quantum Gas

    NASA Astrophysics Data System (ADS)

    Labouvie, Ralf; Santra, Bodhaditya; Heun, Simon; Wimberger, Sandro; Ott, Herwig

    2015-07-01

    We report on the observation of negative differential conductivity (NDC) in a quantum transport device for neutral atoms employing a multimode tunneling junction. The system is realized with a Bose-Einstein condensate loaded in a one-dimensional optical lattice with high site occupancy. We induce an initial difference in chemical potential at one site by local atom removal. The ensuing transport dynamics are governed by the interplay between the tunneling coupling, the interaction energy, and intrinsic collisions, which turn the coherent coupling into a hopping process. The resulting current-voltage characteristics exhibit NDC, for which we identify atom number-dependent tunneling as a new microscopic mechanism. Our study opens new ways for the future implementation and control of complex neutral atom quantum circuits.

  2. Acute transient deafness representing a negative epileptic phenomenon.

    PubMed

    Shahar, Eli; Ravid, Sarit; Genizi, Jacob; Schif, Aharon

    2010-07-01

    We report herein 2 children who presented with acute deafness heralding an epileptic event manifesting thereafter by loss of consciousness and tonic generalized posturing, possibly reflecting a negative epileptic phenomenon. The first previously healthy male had 2 paroxysmal episodes 7 months apart, starting with acute deafness lasting for a few minutes followed by loss of consciousness and generalized tonic posturing for 10 minutes. Electroencephalography (EEG) during the second episodes demonstrated generalized epileptiform discharges. The second with previously controlled partial complex seizures presented with episodes of complete deafness lasting for a few minutes followed by loss of consciousness and focal tonic posturing lasting 10 minutes. Such acute deafness represented an aura of a focal seizure substantiated by right focal temporal epileptic discharges within the region of the primary auditory cortex. Therefore, EEG should be performed in any case of acute transient deafness, even in the absence of accompanying overt clinical seizures. PMID:20042694

  3. Trans-dominant negative mutants of Fos and Jun.

    PubMed Central

    Ransone, L J; Visvader, J; Wamsley, P; Verma, I M

    1990-01-01

    Jun and Fos nuclear oncoproteins form a complex that regulates transcription from promoters containing activator protein AP-1 binding sites. The leucine-zipper and basic-region domains of both Fos and Jun are necessary for formation of the heterodimer that binds to DNA. Reciprocal mutations in the basic region of Fos or Jun can influence the binding of the heterodimer to DNA, implying a symmetrical binding site. DNA-binding mutants of Jun exhibit increased affinity for Fos and are capable of suppressing wild-type Fos-Jun DNA-binding activity. In contrast, mutations in the basic domain of Fos, which prevent binding to DNA in association with Jun, do not significantly diminish the ability of the wild-type heterodimer to bind to DNA. These dominant negative mutants are functional in vivo and can be exploited to study the role of Fos and Jun in normal and transformed cells. Images PMID:2111017

  4. Lipopolysaccharide modification in Gram-negative bacteria during chronic infection.

    PubMed

    Maldonado, Rita F; Sá-Correia, Isabel; Valvano, Miguel A

    2016-07-01

    The Gram-negative bacterial lipopolysaccharide (LPS) is a major component of the outer membrane that plays a key role in host-pathogen interactions with the innate immune system. During infection, bacteria are exposed to a host environment that is typically dominated by inflammatory cells and soluble factors, including antibiotics, which provide cues about regulation of gene expression. Bacterial adaptive changes including modulation of LPS synthesis and structure are a conserved theme in infections, irrespective of the type or bacteria or the site of infection. In general, these changes result in immune system evasion, persisting inflammation and increased antimicrobial resistance. Here, we review the modifications of LPS structure and biosynthetic pathways that occur upon adaptation of model opportunistic pathogens (Pseudomonas aeruginosa, Burkholderia cepacia complex bacteria, Helicobacter pylori and Salmonella enterica) to chronic infection in respiratory and gastrointestinal sites. We also discuss the molecular mechanisms of these variations and their role in the host-pathogen interaction. PMID:27075488

  5. Topological implications of negative curvature for biological and social networks

    NASA Astrophysics Data System (ADS)

    Albert, Réka; DasGupta, Bhaskar; Mobasheri, Nasim

    2014-03-01

    Network measures that reflect the most salient properties of complex large-scale networks are in high demand in the network research community. In this paper we adapt a combinatorial measure of negative curvature (also called hyperbolicity) to parametrized finite networks, and show that a variety of biological and social networks are hyperbolic. This hyperbolicity property has strong implications on the higher-order connectivity and other topological properties of these networks. Specifically, we derive and prove bounds on the distance among shortest or approximately shortest paths in hyperbolic networks. We describe two implications of these bounds to crosstalk in biological networks, and to the existence of central, influential neighborhoods in both biological and social networks.

  6. Negative Differential Conductivity in an Interacting Quantum Gas.

    PubMed

    Labouvie, Ralf; Santra, Bodhaditya; Heun, Simon; Wimberger, Sandro; Ott, Herwig

    2015-07-31

    We report on the observation of negative differential conductivity (NDC) in a quantum transport device for neutral atoms employing a multimode tunneling junction. The system is realized with a Bose-Einstein condensate loaded in a one-dimensional optical lattice with high site occupancy. We induce an initial difference in chemical potential at one site by local atom removal. The ensuing transport dynamics are governed by the interplay between the tunneling coupling, the interaction energy, and intrinsic collisions, which turn the coherent coupling into a hopping process. The resulting current-voltage characteristics exhibit NDC, for which we identify atom number-dependent tunneling as a new microscopic mechanism. Our study opens new ways for the future implementation and control of complex neutral atom quantum circuits. PMID:26274404

  7. Metal complex interactions with DNA.

    PubMed

    Pages, Benjamin J; Ang, Dale L; Wright, Elisé P; Aldrich-Wright, Janice R

    2015-02-28

    Increasing numbers of DNA structures are being revealed using biophysical, spectroscopic and genomic methods. The diversity of transition metal complexes is also growing, as the unique contributions that transition metals bring to the overall structure of metal complexes depend on the various coordination numbers, geometries, physiologically relevant redox potentials, as well as kinetic and thermodynamic characteristics. The vast range of ligands that can be utilised must also be considered. Given this diversity, a variety of biological interactions is not unexpected. Specifically, interactions with negatively-charged DNA can arise due to covalent/coordinate or subtle non-coordinate interactions such as electrostatic attraction, groove binding and intercalation as well as combinations of all of these modes. The potential of metal complexes as therapeutic agents is but one aspect of their utility. Complexes, both new and old, are currently being utilised in conjunction with spectroscopic and biological techniques to probe the interactions of DNA and its many structural forms. Here we present a review of metal complex-DNA interactions in which several binding modes and DNA structural forms are explored. PMID:25427534

  8. Study of negative hydrogen ion beam optics using the 3D3V PIC model

    NASA Astrophysics Data System (ADS)

    Miyamoto, K.; Nishioka, S.; Goto, I.; Hatayama, A.; Hanada, M.; Kojima, A.

    2015-04-01

    The mechanism of negative ion extraction under real conditions with the complex magnetic field is studied by using the 3D PIC simulation code. The extraction region of the negative ion source for the negative ion based neutral beam injection system in fusion reactors is modelled. It is shown that the E x B drift of electrons is caused by the magnetic filter and the electron suppression magnetic field, and the resultant asymmetry of the plasma meniscus. Furthermore, it is indicated that that the asymmetry of the plasma meniscus results in the asymmetry of negative ion beam profile including the beam halo. It could be demonstrated theoretically that the E x B drift is not significantly weakened by the elastic collisions of the electrons with neutral particles.

  9. Study of negative hydrogen ion beam optics using the 3D3V PIC model

    SciTech Connect

    Miyamoto, K.; Nishioka, S.; Goto, I.; Hatayama, A.; Hanada, M.; Kojima, A.

    2015-04-08

    The mechanism of negative ion extraction under real conditions with the complex magnetic field is studied by using the 3D PIC simulation code. The extraction region of the negative ion source for the negative ion based neutral beam injection system in fusion reactors is modelled. It is shown that the E x B drift of electrons is caused by the magnetic filter and the electron suppression magnetic field, and the resultant asymmetry of the plasma meniscus. Furthermore, it is indicated that that the asymmetry of the plasma meniscus results in the asymmetry of negative ion beam profile including the beam halo. It could be demonstrated theoretically that the E x B drift is not significantly weakened by the elastic collisions of the electrons with neutral particles.

  10. 21. WATER TOWERBARRACKS COMPLEX LOOKING SOUTHEAST ACROSS THE PARADE GROUNDS ...

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

    21. WATER TOWER-BARRACKS COMPLEX LOOKING SOUTHEAST ACROSS THE PARADE GROUNDS (Buildings No. 48, 49, 50) (Copy negative made from National Archives negative No. 92-F-61A-13) - Fort Sheridan, 25 miles Northeast of Chicago, on Lake Michigan, Lake Forest, Lake County, IL

  11. 20. WATER TOWERBARRACKS COMPLEX LOOKING SOUTH ACROSS THE PARADE GROUNDS ...

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

    20. WATER TOWER-BARRACKS COMPLEX LOOKING SOUTH ACROSS THE PARADE GROUNDS (Buildings No. 50, 49, 48) (Copy negative made from National Archives negative No. 92-F-61A-12) - Fort Sheridan, 25 miles Northeast of Chicago, on Lake Michigan, Lake Forest, Lake County, IL

  12. The Photopic Negative Response in Idiopathic Intracranial Hypertension

    PubMed Central

    Moss, Heather E.; Park, Jason C.; McAnany, J. Jason

    2015-01-01

    Purpose. To evaluate the photopic negative response (PhNR) as an index of retinal ganglion cell (RGC) function in idiopathic intracranial hypertension (IIH). Methods. Amplitude and implicit time of the PhNR, as elicited by full-field, brief-luminance flashes, was measured in IIH (n = 10) and visually normal control (n = 15) subjects. Visual function was assessed in IIH subjects using standard automated perimetry mean deviation (SAP-MD) scores. Optic nerve structure was evaluated using the Frisén papilledema grading scale (FPG). Macula ganglion cell complex volume (GCCV) was extracted from optical coherence tomography images to assess RGC loss. Results. Median PhNR amplitude was significantly lower in IIH subjects compared with control subjects (P = 0.015, Mann-Whitney Rank Sum [MW]), but implicit time was similar (P = 0.54, MW). In IIH subjects, PhNR amplitude and SAP-MD were correlated (Pearson's r = 0.78, P = 0.008). Ganglion cell complex volume was correlated with both SAP-MD (r = 0.72, P = 0.019) and PhNR amplitude (r = 0.77, P = 0.009). Multivariate linear regression models demonstrated that the correlation between GCCV and PhNR amplitude was improved by accounting for FPG in the model (r = 0.94, P < 0.0001), but the correlation between GCCV and SAP-MD was not (r = 0.74, P = 0.009). Conclusions. Photopic negative response amplitude, which can be decreased in IIH subjects, correlates well with a clinical measure of visual function (SAP-MD). In multivariate models, it correlated with both an imaging measure of chronic ganglion cell injury (GCCV) and a clinical measure of acute optic nerve head pathology (FPG). Further studies are needed to determine the clinical utility of PhNR as a marker for diagnosis and monitoring of IIH. PMID:26047172

  13. Lattice gluodynamics at negative g{sup 2}

    SciTech Connect

    Li, L.; Meurice, Y.

    2005-01-01

    We consider Wilson's SU(N) lattice gauge theory (without fermions) at negative values of {beta}=2N/g{sup 2} and for N=2 or 3. We show that in the limit {beta}{yields}-{infinity}, the path integral is dominated by configurations where links variables are set to a nontrivial element of the center on selected nonintersecting lines. For N=2, these configurations can be characterized by a unique gauge invariant set of variables, while for N=3 a multiplicity growing with the volume as the number of configurations of an Ising model is observed. In general, there is a discontinuity in the average plaquette when g{sup 2} changes its sign which prevents us from having a convergent series in g{sup 2} for this quantity. For N=2, a change of variables relates the gauge invariant observables at positive and negative values of {beta}. For N=3, we derive an identity relating the observables at {beta} with those at {beta} rotated by {+-}2{pi}/3 in the complex plane and show numerical evidence for a Ising like first order phase transition near {beta}=-22. We discuss the possibility of having lines of first order phase transitions ending at a second order phase transition in an extended bare parameter space.

  14. Positive and negative regulators of the metallothionein gene (review).

    PubMed

    Takahashi, Shinichiro

    2015-07-01

    Metallothioneins (MTs) are metal-binding proteins involved in diverse processes, including metal homeostasis and detoxification, the oxidative stress response and cell proliferation. Aberrant expression and silencing of these genes are important in a number of diseases. Several positive regulators of MT genes, including metal-responsive element-binding transcription factor (MTF)-1 and upstream stimulatory factor (USF)-1, have been identified and mechanisms of induction have been well described. However, the negative regulators of MT genes remain to be elucidated. Previous studies from the group of the present review have revealed that the hematopoietic master transcription factor, PU.1, directly represses the expression levels of MT genes through its epigenetic activities, and upregulation of MT results in the potent inhibition of myeloid differentiation. The present review focuses on PU.1 and several other negative regulators of this gene, including PZ120, DNA methyltransferase 3a with Mbd3 and Brg1 complex, CCAAT enhancer binding protein α and Ku protein, and describes the suppression of the MT genes through these transcription factors. PMID:25760317

  15. CD23 can negatively regulate B-cell receptor signaling

    PubMed Central

    Liu, Chaohong; Richard, Katharina; Wiggins, Melvin; Zhu, Xiaoping; Conrad, Daniel H.; Song, Wenxia

    2016-01-01

    CD23 has been implicated as a negative regulator of IgE and IgG antibody responses. However, whether CD23 has any role in B-cell activation remains unclear. We examined the expression of CD23 in different subsets of peripheral B cells and the impact of CD23 expression on the early events of B-cell receptor (BCR) activation using CD23 knockout (KO) mice. We found that in addition to marginal zone B cells, mature follicular B cells significantly down regulate the surface expression level of CD23 after undergoing isotype switch and memory B-cell differentiation. Upon stimulation with membrane-associated antigen, CD23 KO causes significant increases in the area of B cells contacting the antigen-presenting membrane and the magnitude of BCR clustering. This enhanced cell spreading and BCR clustering is concurrent with increases in the levels of phosphorylation of tyrosine and Btk, as well as the levels of F-actin and phosphorylated Wiskott Aldrich syndrome protein, an actin nucleation promoting factor, in the contract zone of CD23 KO B cells. These results reveal a role of CD23 in the negative regulation of BCR signaling in the absence of IgE immune complex and suggest that CD23 down-regulates BCR signaling by influencing actin-mediated BCR clustering and B-cell morphological changes. PMID:27181049

  16. Noise Control in Gene Regulatory Networks with Negative Feedback.

    PubMed

    Hinczewski, Michael; Thirumalai, D

    2016-07-01

    Genes and proteins regulate cellular functions through complex circuits of biochemical reactions. Fluctuations in the components of these regulatory networks result in noise that invariably corrupts the signal, possibly compromising function. Here, we create a practical formalism based on ideas introduced by Wiener and Kolmogorov (WK) for filtering noise in engineered communications systems to quantitatively assess the extent to which noise can be controlled in biological processes involving negative feedback. Application of the theory, which reproduces the previously proven scaling of the lower bound for noise suppression in terms of the number of signaling events, shows that a tetracycline repressor-based negative-regulatory gene circuit behaves as a WK filter. For the class of Hill-like nonlinear regulatory functions, this type of filter provides the optimal reduction in noise. Our theoretical approach can be readily combined with experimental measurements of response functions in a wide variety of genetic circuits, to elucidate the general principles by which biological networks minimize noise. PMID:27095600

  17. Wigner time delay in photodetachment of negative ions

    NASA Astrophysics Data System (ADS)

    Saha, S.; Deshmukh, P. C.; Jose, J.; Kkeifets, A. S.; Manson, S. T.

    2016-05-01

    In recent years, there has been much interest in studies on Wigner time delay in atomic photoionization using various experimental techniques and theoretical methodologies. In the present work, we report time delay in the photodetachment of negative ions using the relativistic-random-phase approximation (RRPA), which includes relativistic and important correlation effects. Time delay is obtained as energy derivative of phase of the photodetachment complex transition amplitude. We investigate the time delay in the dipole n p --> ɛd channels in the photodetachment of F- and Cl-, and in n f --> ɛg channels in the photodetachment of Tm-. In photodetachment of the negative ions, the photoelectron escapes in the field of the neutral atom and thus does not experience the nuclear Coulomb field; hence the phase is devoid of the Coulomb component. The systems chosen are well suited to examine the sensitivity of the photodetachment time delay to the centrifugal potential. The ions chosen have closed shells, and thus amenable to the RPA. Work supported by DOE, Office of Chemical Sciences, DST (India), and the Australian Research Council.

  18. Inhaled Antibiotics for Gram-Negative Respiratory Infections.

    PubMed

    Wenzler, Eric; Fraidenburg, Dustin R; Scardina, Tonya; Danziger, Larry H

    2016-07-01

    Gram-negative organisms comprise a large portion of the pathogens responsible for lower respiratory tract infections, especially those that are nosocomially acquired, and the rate of antibiotic resistance among these organisms continues to rise. Systemically administered antibiotics used to treat these infections often have poor penetration into the lung parenchyma and narrow therapeutic windows between efficacy and toxicity. The use of inhaled antibiotics allows for maximization of target site concentrations and optimization of pharmacokinetic/pharmacodynamic indices while minimizing systemic exposure and toxicity. This review is a comprehensive discussion of formulation and drug delivery aspects, in vitro and microbiological considerations, pharmacokinetics, and clinical outcomes with inhaled antibiotics as they apply to disease states other than cystic fibrosis. In reviewing the literature surrounding the use of inhaled antibiotics, we also highlight the complexities related to this route of administration and the shortcomings in the available evidence. The lack of novel anti-Gram-negative antibiotics in the developmental pipeline will encourage the innovative use of our existing agents, and the inhaled route is one that deserves to be further studied and adopted in the clinical arena. PMID:27226088

  19. CD23 can negatively regulate B-cell receptor signaling.

    PubMed

    Liu, Chaohong; Richard, Katharina; Wiggins, Melvin; Zhu, Xiaoping; Conrad, Daniel H; Song, Wenxia

    2016-01-01

    CD23 has been implicated as a negative regulator of IgE and IgG antibody responses. However, whether CD23 has any role in B-cell activation remains unclear. We examined the expression of CD23 in different subsets of peripheral B cells and the impact of CD23 expression on the early events of B-cell receptor (BCR) activation using CD23 knockout (KO) mice. We found that in addition to marginal zone B cells, mature follicular B cells significantly down regulate the surface expression level of CD23 after undergoing isotype switch and memory B-cell differentiation. Upon stimulation with membrane-associated antigen, CD23 KO causes significant increases in the area of B cells contacting the antigen-presenting membrane and the magnitude of BCR clustering. This enhanced cell spreading and BCR clustering is concurrent with increases in the levels of phosphorylation of tyrosine and Btk, as well as the levels of F-actin and phosphorylated Wiskott Aldrich syndrome protein, an actin nucleation promoting factor, in the contract zone of CD23 KO B cells. These results reveal a role of CD23 in the negative regulation of BCR signaling in the absence of IgE immune complex and suggest that CD23 down-regulates BCR signaling by influencing actin-mediated BCR clustering and B-cell morphological changes. PMID:27181049

  20. 6. Photographic copy of a photograph taken from pasteup negatives ...

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

    6. Photographic copy of a photograph taken from paste-up negatives for U.S. Army Corps of Engineers document GF-500-MCP, entitled "Grand Forks Site RLS Army Operating Drawings, Master Composite Photographs for SAFEGUARD TSE Systems and Equipment," Page 9, dated 1 September 1974 (original document and negatives in possession of U.S. Army Corps of Engineers, Huntsville, AL). Photographer unknown. View of remote launch operations building, power generation room #124, showing no-break units NB-1002 (A) and NB-1001 (B). This equipment consisted of a 150 horsepower, d.c. operational motor which drove, on each end of the extended shaft, a 70 kw generator and a 30 kw generator unit. It was designed to provide continuous power service for launch equipment. In particular, the photo is an excellent representation of the shock isolation scheme, as evidenced by the supporting air springs and equipment platform - Stanley R. Mickelsen Safeguard Complex, Remote Launch Operations Building, Near Service Road exit from Patrol Road, Nekoma, Cavalier County, ND

  1. Negative Mood Increases Selective Attention to Negatively Valenced Body Parts in Female Adolescents with Anorexia Nervosa

    PubMed Central

    Svaldi, Jennifer; Bender, Caroline; Caffier, Detlef; Ivanova, Viliana; Mies, Nina; Fleischhaker, Christian; Tuschen-Caffier, Brunna

    2016-01-01

    Objective Previous research has yielded evidence of increased attentional processing of negatively valenced body parts in women with anorexia nervosa (AN), especially for those with high depressive symptomatology. The present study extended previous research by implementing an experimental mood manipulation. Method In a within-subjects design, female adolescents with AN (n = 12) and an age matched female control group (CG; n = 12) were given a negative and a positive mood induction at a one-week interval. After each mood induction, participants underwent a 3-min mirror exposure, while their eye movements were recorded. Results After the positive mood induction, both AN and CG participants displayed longer and more frequent gazes towards their self-defined most ugly relative to their self-defined most beautiful body part. However, after the negative mood induction, only females with AN were characterized by increased attention to their most ugly compared to their most beautiful body part, while CG participants’ attention distribution was balanced. Furthermore, in the negative (but not in the positive) mood induction condition gaze frequency and duration towards the most ugly body part was significantly stronger in the AN group relative to the CG. Discussion The results emphasize the role of negative mood in the maintenance of pathological information processing of the self-body. This increased body-related negativity-bias during negative mood may lead to the persistence and aggravation of AN patients’ body image disturbance. PMID:27123587

  2. Turning negative into positive: public health mass media campaigns and negative advertising

    PubMed Central

    Apollonio, D. E.; Malone, R. E.

    2009-01-01

    Literature suggests that ‘negative advertising’ is an effective way to encourage behavioral changes, but it has enjoyed limited use in public health media campaigns. However, as public health increasingly focuses on non-communicable disease prevention, negative advertising could be more widely applied. This analysis considers an illustrative case from tobacco control. Relying on internal tobacco industry documents, surveys and experimental data and drawing from political advocacy literature, we describe tobacco industry and public health research on the American Legacy Foundation’s “truth” campaign, an example of effective negative advertising in the service of public health. The tobacco industry determined that the most effective advertisements run by Legacy’s “truth” campaign were negative advertisements. Although the tobacco industry’s own research suggested that these negative ads identified and effectively reframed the cigarette as a harmful consumer product rather than focusing solely on tobacco companies, Philip Morris accused Legacy of ‘vilifying’ it. Public health researchers have demonstrated the effectiveness of the “truth” campaign in reducing smoking initiation. Research on political advocacy demonstrating the value of negative advertising has rarely been used in the development of public health media campaigns, but negative advertising can effectively communicate certain public health messages and serve to counter corporate disease promotion. PMID:18948569

  3. Negative-stiffness-mechanism vibration isolation systems

    NASA Astrophysics Data System (ADS)

    Platus, David L.

    1992-02-01

    A new type of vibration isolation system offers significant improvement in performance compared with current state-of-the-art systems. The system uses negative-stiffness mechanisms to cancel the stiffness of a spring suspension. Reduction in stiffness magnifies the damping inherent in the system creating a practical means for achieving high hysteretic damping. The result is a simple, compact 6-DOF passive isolation system capable of system resonant frequencies below 0.2 Hz and first isolator resonances above 100 Hz. Resonant transmissibilities below 1.4 can be achieved with transmissibilities at the higher frequencies close to that of the ideal undamped system. The negative-stiffness mechanisms can cancel the stiffness of power cables, hoses or other lines connected to payloads. This paper develops the theory, describes typical configurations and summarizes test data with prototype systems.

  4. Cesium injection system for negative ion duoplasmatrons

    DOEpatents

    Kobayashi, Maasaki; Prelec, Krsto; Sluyters, Theodorus J

    1978-01-01

    Longitudinally extending, foraminous cartridge means having a cylindrical side wall forming one flat, circular, tip end surface and an opposite end; an open-ended cavity, and uniformly spaced orifices for venting the cavity through the side wall in the annulus of a plasma ring for uniformly ejecting cesium for coating the flat, circular, surface. To this end, the cavity is filled with a cesium containing substance and attached to a heater in a hollow-discharge duoplasmatron. By coating the flat circular surface with a uniform monolayer of cesium and locating it in an electrical potential well at the end of a hollow-discharge, ion duoplasmatron source of an annular hydrogen plasma ring, the negative hydrogen production from the duoplasmatron is increased. The negative hydrogen is produced on the flat surface of the cartridge and extracted by the electrical potential well along a trajectory coaxial with the axis of the plasma ring.

  5. New types of negative ion sources

    SciTech Connect

    Borisko, V.N.; Lapshin, V.I.

    1995-12-31

    The plasma sources of negative ions which were elaborated in Kharkov State University are considered in this paper. These sources use the mechanism of dissociative stick of electrons with low energies to molecules of a working gas. The effective work of such sources needs a special system of low energy electrons formation. The effect of secondary electron emission used in negative ion sources is considered. The electrode material with a great coefficient of secondary electron emission allows one to obtain a few slow electrons per one bombarding electron. A plasma of Penning discharge is an emitter of initial elections. The electron electromagnetic trap in the secondary electron emission region allows one to enlarge volume of interaction of low energy electrons with the working gas molecules. The lifetime of slow electrons grows in this trap.

  6. Radiation quality of beams of negative pions

    SciTech Connect

    Dicello, J.F.; Brenner, D.J.

    1981-01-01

    As a negative pion stops in tissue, it attaches itself to an adjacent atom to form a mesonic atom. Subsequently, the wave function of the pion interacts with that of the nucleus and the pion is absorbed. Because the energy associated with the rest mass of the pion is greater than the separation energy of the nuclear particles, the nucleus disintegrates (pion star). In tissue, approximately 40 MeV goes into overcoming the binding energies; 20 MeV goes into kinetic energy of charged particles; 80 MeV goes into kinetic energy of neutrons. In cases where biological studies are performed with beams of negative pions, as much as 20% of the total absorbed dose in the treatment volume and about 50% of the high-LET dose (> 100 keV/..mu..m) can result from neutrons. The degree of biological response and the variation of that response throughout the treatment volume can be altered by the neutron dose.

  7. Mechanical metamaterials with negative compressibility transitions

    NASA Astrophysics Data System (ADS)

    Nicolaou, Zachary G.; Motter, Adilson E.

    2012-07-01

    When tensioned, ordinary materials expand along the direction of the applied force. Here, we explore network concepts to design metamaterials exhibiting negative compressibility transitions, during which a material undergoes contraction when tensioned (or expansion when pressured). Continuous contraction of a material in the same direction of an applied tension, and in response to this tension, is inherently unstable. The conceptually similar effect we demonstrate can be achieved, however, through destabilizations of (meta)stable equilibria of the constituents. These destabilizations give rise to a stress-induced solid-solid phase transition associated with a twisted hysteresis curve for the stress-strain relationship. The strain-driven counterpart of negative compressibility transitions is a force amplification phenomenon, where an increase in deformation induces a discontinuous increase in response force. We suggest that the proposed materials could be useful for the design of actuators, force amplifiers, micromechanical controls, and protective devices.

  8. Negative emotional stimuli enhance vestibular processing.

    PubMed

    Preuss, Nora; Ellis, Andrew W; Mast, Fred W

    2015-08-01

    Recent studies have shown that vestibular stimulation can influence affective processes. In the present study, we examined whether emotional information can also modulate vestibular perception. Participants performed a vestibular discrimination task on a motion platform while viewing emotional pictures. Six different picture categories were taken from the International Affective Picture System: mutilation, threat, snakes, neutral objects, sports, and erotic pictures. Using a Bayesian hierarchical approach, we were able to show that vestibular discrimination improved when participants viewed emotionally negative pictures (mutilation, threat, snake) when compared to neutral/positive objects. We conclude that some of the mechanisms involved in the processing of vestibular information are also sensitive to emotional content. Emotional information signals importance and mobilizes the body for action. In case of danger, a successful motor response requires precise vestibular processing. Therefore, negative emotional information improves processing of vestibular information. PMID:26098730

  9. Accounting for false negatives in hotspot detection

    SciTech Connect

    Sego, Landon H.; Wilson, John E.

    2007-08-28

    Hotspot sampling designs are used in environmental sampling to identify the location of one (or more) contiguous regions of elevated contamination. These regions are known as hotspots. The problem of how to calculate the probability of detecting an elliptical hotspot using a rectangular or triangular grid of sampling points was addressed by Singer and Wickman in 1969. This approach presumed that any sample which coincided with a hotspot would detect the hotspot without error. However, for many sampling methodologies, there is a chance that the hotspot will not be detected even though it has been sampled directly--a false negative. We present a mathematical solution and a numerical algorithm which account for false negatives when calculating the probability of detecting hotspots that are circular in shape.

  10. Mechanical metamaterials with negative compressibility transitions.

    PubMed

    Nicolaou, Zachary G; Motter, Adilson E

    2012-07-01

    When tensioned, ordinary materials expand along the direction of the applied force. Here, we explore network concepts to design metamaterials exhibiting negative compressibility transitions, during which a material undergoes contraction when tensioned (or expansion when pressured). Continuous contraction of a material in the same direction of an applied tension, and in response to this tension, is inherently unstable. The conceptually similar effect we demonstrate can be achieved, however, through destabilizations of (meta)stable equilibria of the constituents. These destabilizations give rise to a stress-induced solid-solid phase transition associated with a twisted hysteresis curve for the stress-strain relationship. The strain-driven counterpart of negative compressibility transitions is a force amplification phenomenon, where an increase in deformation induces a discontinuous increase in response force. We suggest that the proposed materials could be useful for the design of actuators, force amplifiers, micromechanical controls, and protective devices. PMID:22609557

  11. Nociception, pain, negative moods and behavior selection

    PubMed Central

    Baliki, Marwan N.; Apkarian, A. Vania

    2015-01-01

    Recent neuroimaging studies suggest that the brain adapts with pain, as well as imparts risk for developing chronic pain. Within this context we revisit the concepts for nociception, acute and chronic pain, and negative moods relative to behavior selection. We redefine nociception as the mechanism protecting the organism from injury; while acute pain as failure of avoidant behavior; and a mesolimbic threshold process that gates the transformation of nociceptive activity to conscious pain. Adaptations in this threshold process are envisioned to be critical for development of chronic pain. We deconstruct chronic pain into four distinct phases, each with specific mechanisms; and outline current state of knowledge regarding these mechanisms: The limbic brain imparting risk, while mesolimbic learning processes reorganizing the neocortex into a chronic pain state. Moreover, pain and negative moods are envisioned as a continuum of aversive behavioral learning, which enhance survival by protecting against threats. PMID:26247858

  12. Mechanical Metamaterials with Negative Compressibility Transitions

    NASA Astrophysics Data System (ADS)

    Motter, Adilson

    2015-03-01

    When tensioned, ordinary materials expand along the direction of the applied force. In this presentation, I will explore network concepts to design metamaterials exhibiting negative compressibility transitions, during which the material undergoes contraction when tensioned (or expansion when pressured). Such transitions, which are forbidden in thermodynamic equilibrium, are possible during the decay of metastable, super-strained states. I will introduce a statistical physics theory for negative compressibility transitions, derive a first-principles model to predict these transitions, and present a validation of the model using molecular dynamics simulations. Aside from its immediate mechanical implications, our theory points to a wealth of analogous inverted responses, such as inverted susceptibility or heat-capacity transitions, allowed when considering realistic scales. This research was done in collaboration with Zachary Nicolaou, and was supported by the National Science Foundation and the Alfred P. Sloan Foundation.

  13. Proactive and retroactive effects of negative suggestion.

    PubMed

    Brown, Alan S; Brown, Christine M; Mosbacher, Joy L; Dryden, W Erich

    2006-11-01

    The negative effects of false information presented either prior to (proactive interference; PI) or following (retroactive interference; RI) true information was examined with word definitions (Experiment 1) and trivia facts (Experiment 2). Participants were explicitly aware of which information was true and false when shown, and true-false discrimination was evaluated via multiple-choice tests. Negative suggestion, defined as poorer performance on interference items than noninterference (control) items, consistently occurred when the wrong information followed the correct information (RI) but not when it preceded the correct information (PI). These effects did not change as a function of retention interval (immediate, 1 week, or 3 weeks) or number of incorrect alternatives (1 or 3). Implications of this outcome for experiencing incorrect information in both academic and nonacademic situations are considered. PMID:17087580

  14. Structures with negative index of refraction

    DOEpatents

    Soukoulis, Costas M.; Zhou, Jiangfeng; Koschny, Thomas; Zhang, Lei; Tuttle, Gary

    2011-11-08

    The invention provides simplified negative index materials (NIMs) using wire-pair structures, 4-gap single ring split-ring resonator (SRR), fishnet structures and overleaf capacitor SRR. In the wire-pair arrangement, a pair of short parallel wires and continuous wires are used. In the 4-gap single-ring SRR, the SRRs are centered on the faces of a cubic unit cell combined with a continuous wire type resonator. Combining both elements creates a frequency band where the metamaterial is transparent with simultaneously negative .di-elect cons. and .mu.. In the fishnet structure, a metallic mesh on both sides of the dielectric spacer is used. The overleaf capacitor SRR changes the gap capacities to small plate capacitors by making the sections of the SRR ring overlap at the gaps separated by a thin dielectric film. This technique is applicable to conventional SRR gaps but it best deploys for the 4-gap single-ring structures.

  15. Ground state of the hydrogen negative ion

    NASA Astrophysics Data System (ADS)

    Obreshkov, Boyan

    2009-03-01

    Based on recently developed variational many-body Schr"odinger equation for electrons with Coulomb interactions [1], we provide first numerical results for the ground state electron structure of the hydrogen negative ion. It is shown that Fermi-Teller promotion effect together with non-adiabatic screening effects due to the Pauli's exclusion principle are responsible for the weak binding of the anion. The calculated ionization potential J=-1/2 - 2 λ+ <1/r12> of the hydrogen negative ion is compared with the experiment, where λ is the mean binding energy per one electron in the ground state.[0pt] [1] B. D. Obreshkov , Phys. Rev. A 78, 032503 (2008).

  16. Experimental Evaluation of a Negative Ion Source for a Heavy Ion Fusion Negative Ion Driver

    SciTech Connect

    Grisham, L. R.; Hahto, S. K.; Hahto, S. T.; Kwan, J. W.; Leung, K. N.

    2004-06-16

    Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photo-detached to neutrals. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm{sup 2} was obtained under the same conditions that gave 57 45 mA/cm{sup 2} of positive chlorine, suggesting the presence of nearly as many negative ions as positive ions in the plasma near the extraction plane. The negative ion spectrum was 99.5% atomic chlorine ions, with only 0.5% molecular chlorine, and essentially no impurities. Although this experiment did not incorporate the type of electron suppression technology that i s used in negative hydrogen beam extraction, the ratio of co-extracted electrons to Cl{sup -} was as low as 7 to 1, many times lower than the ratio of their mobilities, suggesting that few electrons are present in the near-extractor plasma. This, along with the near-equivalence of the positive and negative ion currents, suggests that the plasma in this region was mostly an ion-ion plasma. The negative chlorine current density was relatively insensitive to pressure, and scaled linearly with RF power. If this linear scaling continues to hold at higher RF powers, it should permit current densities of 100 45 mA/cm{sup 2}, sufficient for present heavy ion fusion injector concepts. The effective ion temperatures of the positive and negative ions appeared to be similar and relatively low for a plasma source.

  17. Experimental evaluation of a negative ion source for a heavy ionfusion negative ion driver

    SciTech Connect

    Grisham, L.R.; Hahto, S.K.; Hahto, S.T.; Kwan, J.W.; Leung, K.N.

    2005-01-18

    Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photodetached to neutrals [1,2,3]. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm{sup 2} was obtained under the same conditions that gave 57 mA/cm{sup 2} of positive chlorine, suggesting the presence of nearly as many negative ions as positive ions in the plasma near the extraction plane. The negative ion spectrum was 99.5% atomic chlorine ions, with only 0.5% molecular chlorine, and essentially no impurities. Although this experiment did not incorporate the type of electron suppression technology that is used in negative hydrogen beam extraction, the ratio of co-extracted electrons to Cl{sup -} was as low as 7 to 1, many times lower than the ratio of their mobilities, suggesting that few electrons are present in the near-extractor plasma. This, along with the near-equivalence of the positive and negative ion currents, suggests that the plasma in this region was mostly an ion-ion plasma. The negative chlorine current density was relatively insensitive to pressure, and scaled linearly with RF power. If this linear scaling continues to hold at higher RF powers, it should permit current densities of 100 mA/cm{sup 2}, sufficient for present heavy ion fusion injector concepts. The effective ion temperatures of the positive and negative ions appeared to be similar and relatively low for a plasma source.

  18. Generation of intense negative ion beams

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Orient, Otto J. (Inventor); Aladzhadzhyan, Samuel H. (Inventor)

    1987-01-01

    An electron gun is used with a mirror electrostatic field to produce zero or near zero velocity electrons by forming a turning point in their trajectories. A gas capable of attaching zero or near zero velocity is introduced at this turning point, and negative ions are produced by the attachment or dissociative attachment process. Operation may be continuous or pulsed. Ions thus formed are extracted by a simple lens system and suitable biasing of grids.

  19. Negative Electrodes for Li-Ion Batteries

    SciTech Connect

    Kinoshita, Kim; Zaghib, Karim

    2001-10-01

    Graphitized carbons have played a key role in the successful commercialization of Li-ion batteries. The physicochemical properties of carbon cover a wide range; therefore identifying the optimum active electrode material can be time consuming. The significant physical properties of negative electrodes for Li-ion batteries are summarized, and the relationship of these properties to their electrochemical performance in nonaqueous electrolytes, are discussed in this paper.

  20. The 'negative cost' of value engineering.

    PubMed

    Wilkinson, Martin

    2012-06-01

    Martin Wilkinson, national sales manager at system protection specialist, Spirotech UK, highlights the 'potential negative consequences' of value engineering in heating system specification in the healthcare sector, and argues that system protection products such as de-aerators and dirt separators have considerable value in preventative maintenance, and in helping to extend the useful life of both the system as a whole, and its vital parts. PMID:22764628

  1. Thyroid antibody-negative euthyroid Graves’ ophthalmopathy

    PubMed Central

    Khan, Ishrat; Taylor, Peter; Das, Gautam; Okosieme, Onyebuchi E

    2016-01-01

    Summary TSH receptor antibodies (TRAbs) are the pathological hallmark of Graves’ disease, present in nearly all patients with the disease. Euthyroid Graves’ ophthalmopathy (EGO) is a well-recognized clinical entity, but its occurrence in patients with negative TRAbs is a potential source of diagnostic confusion. A 66-year-old female presented to our endocrinology clinic with right eye pain and diplopia in the absence of thyroid dysfunction. TRAbs were negative, as measured with a highly sensitive third-generation thyrotropin-binding inhibitory immunoglobulin (TBII) ELISA assay. CT and MRI scans of the orbit showed asymmetrical thickening of the inferior rectus muscles but no other inflammatory or malignant orbital pathology. Graves’ ophthalmopathy (GO) was diagnosed on the basis of the clinical and radiological features, and she underwent surgical recession of the inferior rectus muscle with complete resolution of the diplopia and orbital pain. She remained euthyroid over the course of follow-up but ultimately developed overt clinical and biochemical hyperthyroidism, 24 months after the initial presentation. By this time, she had developed positive TRAb as well as thyroid peroxidase antibodies. She responded to treatment with thionamides and remains euthyroid. This case highlights the potential for negative thyroid-specific autoantibodies in the presentation of EGO and underscores the variable temporal relationship between the clinical expression of thyroid dysfunction and orbital disease in the natural evolution of Graves’ disease. Learning points Euthyroid Graves’ ophthalmopathy can present initially with negative thyroid-specific autoantibodies. Patients with suggestive symptoms of ophthalmopathy should be carefully evaluated for GO with imaging studies even when thyroid function and autoantibodies are normal. Patients with EGO can develop thyroid dysfunction within 4 years of follow-up underpinning the need for long-term follow-up and continued

  2. Hydrophobic surfactant proteins strongly induce negative curvature.

    PubMed

    Chavarha, Mariya; Loney, Ryan W; Rananavare, Shankar B; Hall, Stephen B

    2015-07-01

    The hydrophobic surfactant proteins SP-B and SP-C greatly accelerate the adsorption of vesicles containing the surfactant lipids to form a film that lowers the surface tension of the air/water interface in the lungs. Pulmonary surfactant enters the interface by a process analogous to the fusion of two vesicles. As with fusion, several factors affect adsorption according to how they alter the curvature of lipid leaflets, suggesting that adsorption proceeds via a rate-limiting structure with negative curvature, in which the hydrophilic face of the phospholipid leaflets is concave. In the studies reported here, we tested whether the surfactant proteins might promote adsorption by inducing lipids to adopt a more negative curvature, closer to the configuration of the hypothetical intermediate. Our experiments used x-ray diffraction to determine how the proteins in their physiological ratio affect the radius of cylindrical monolayers in the negatively curved, inverse hexagonal phase. With binary mixtures of dioleoylphosphatidylethanolamine (DOPE) and dioleoylphosphatidylcholine (DOPC), the proteins produced a dose-related effect on curvature that depended on the phospholipid composition. With DOPE alone, the proteins produced no change. With an increasing mol fraction of DOPC, the response to the proteins increased, reaching a maximum 50% reduction in cylindrical radius at 5% (w/w) protein. This change represented a doubling of curvature at the outer cylindrical surface. The change in spontaneous curvature, defined at approximately the level of the glycerol group, would be greater. Analysis of the results in terms of a Langmuir model for binding to a surface suggests that the effect of the lipids is consistent with a change in the maximum binding capacity. Our findings show that surfactant proteins can promote negative curvature, and support the possibility that they facilitate adsorption by that mechanism. PMID:26153706

  3. Lower body graduated negative pressure system

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The first task concerning the Lower Body Negative Pressure Suit was to determine the best type construction for a leg section with these goals in mind: good mobility, minimum amount of bulk, ease of storage, lightweight, rigid enough to withstand atmospheric pressure, and minimum amount of preparation before donning and donning time. After a study of three systems, wire hoops (rings) separated on inch apart in an airtight material furnished by NASA were chosen.

  4. Veillonella, Firmicutes: Microbes disguised as Gram negatives

    PubMed Central

    Vesth, Tammi; Ozen, Aslı; Andersen, Sandra C.; Kaas, Rolf Sommer; Lukjancenko, Oksana; Bohlin, Jon; Nookaew, Intawat; Wassenaar, Trudy M.; Ussery, David W.

    2013-01-01

    The Firmicutes represent a major component of the intestinal microflora. The intestinal Firmicutes are a large, diverse group of organisms, many of which are poorly characterized due to their anaerobic growth requirements. Although most Firmicutes are Gram positive, members of the class Negativicutes, including the genus Veillonella, stain Gram negative. Veillonella are among the most abundant organisms of the oral and intestinal microflora of animals and humans, in spite of being strict anaerobes. In this work, the genomes of 24 Negativicutes, including eight Veillonella spp., are compared to 20 other Firmicutes genomes; a further 101 prokaryotic genomes were included, covering 26 phyla. Thus a total of 145 prokaryotic genomes were analyzed by various methods to investigate the apparent conflict of the Veillonella Gram stain and their taxonomic position within the Firmicutes. Comparison of the genome sequences confirms that the Negativicutes are distantly related to Clostridium spp., based on 16S rRNA, complete genomic DNA sequences, and a consensus tree based on conserved proteins. The genus Veillonella is relatively homogeneous: inter-genus pair-wise comparison identifies at least 1,350 shared proteins, although less than half of these are found in any given Clostridium genome. Only 27 proteins are found conserved in all analyzed prokaryote genomes. Veillonella has distinct metabolic properties, and significant similarities to genomes of Proteobacteria are not detected, with the exception of a shared LPS biosynthesis pathway. The clade within the class Negativicutes to which the genus Veillonella belongs exhibits unique properties, most of which are in common with Gram-positives and some with Gram negatives. They are only distantly related to Clostridia, but are even less closely related to Gram-negative species. Though the Negativicutes stain Gram-negative and possess two membranes, the genome and proteome analysis presented here confirm their place within the

  5. SIGIRR, a negative regulator of colon tumorigenesis

    PubMed Central

    Zhao, Junjie; Zepp, Jarod; Bulek, Katarzyna; Li, Xiaoxia

    2012-01-01

    Inappropriate activation of the Toll-IL-1R (TL-IL-1) signaling by commensal bacteria contributes to the pathogenesis of inflammatory bowel diseases and colitis-associated cancer. Recent studies have identified SIGIRR as a negative regulator of TL-IL-1 signaling. It dampens intestinal inflammation and tumorigenesis in the colon. In this review, we will discuss the role of SIGIRR in different cell types and the mechanisms underlying its tumor suppressor function. PMID:22529873

  6. Negative refractive index, perfect lenses and checkerboards: Trapping and imaging effects in folded optical spaces

    NASA Astrophysics Data System (ADS)

    Guenneau, Sébastien; Ramakrishna, S. Anantha

    2009-06-01

    Newly discovered metamaterials have opened new vistas for better control of light via negative refraction, whereby light refracts in the "wrong" manner. These are dielectric and metallic composite materials structured at subwavelength lengthscales. Their building blocks consist of local resonators such as conducting thin bars and split rings driving the material parameters such as the dielectric permittivity and magnetic permeability to negative (complex) values. Combined together, these structural elements can bring about a (complex valued) negative effective refractive index for the Snell-Descartes law and result in negative refraction of radiation. Negative refractive index materials can support a host of surface plasmon states for both polarizations of light. This makes possible unique effects such as imaging with subwavelength image resolution through the Pendry-Veselago slab lens. Other geometries have also been investigated, such as cylindrical or spherical lenses that enable a magnification of images with subwavelength resolution. Superlenses of three-fold (equilateral triangle), four-fold (square) and six-fold (hexagonal) geometry allow for multiple images, respectively two, three, and five. Generalization to rectangular and triangular checkerboards consisting of alternating cells of positive and negative refractive index represents a very singular situation in which the density of modes diverges at the corners, with an infinity of images. Sine-cosecant anisotropic heterogeneous square and triangular checkerboards can be respectively mapped onto three-dimensional cubic and icosahedral corner lenses consisting of alternating positive and negative refractive regions. All such systems with corners between negative and positive refractive media display very singular behavior with the local density of states becoming infinitely large at the corner, in the limit of no dissipation. We investigate all of these, using the unifying viewpoint of transformation optics

  7. A computational approach to negative priming

    NASA Astrophysics Data System (ADS)

    Schrobsdorff, H.; Ihrke, M.; Kabisch, B.; Behrendt, J.; Hasselhorn, M.; Herrmann, J. Michael

    2007-09-01

    Priming is characterized by a sensitivity of reaction times to the sequence of stimuli in psychophysical experiments. The reduction of the reaction time observed in positive priming is well-known and experimentally understood (Scarborough et al., J. Exp. Psycholol: Hum. Percept. Perform., 3, pp. 1-17, 1977). Negative priming—the opposite effect—is experimentally less tangible (Fox, Psychonom. Bull. Rev., 2, pp. 145-173, 1995). The dependence on subtle parameter changes (such as response-stimulus interval) usually varies. The sensitivity of the negative priming effect bears great potential for applications in research in fields such as memory, selective attention, and ageing effects. We develop and analyse a computational realization, CISAM, of a recent psychological model for action decision making, the ISAM (Kabisch, PhD thesis, Friedrich-Schiller-Universitat, 2003), which is sensitive to priming conditions. With the dynamical systems approach of the CISAM, we show that a single adaptive threshold mechanism is sufficient to explain both positive and negative priming effects. This is achieved by comparing results obtained by the computational modelling with experimental data from our laboratory. The implementation provides a rich base from which testable predictions can be derived, e.g. with respect to hitherto untested stimulus combinations (e.g. single-object trials).

  8. Lesion-negative anterior cingulate epilepsy.

    PubMed

    Lacuey, Nuria; Davila, Javier Chapa; Zonjy, Bilal; Amina, Shahram; Couce, Marta; Turnbull, John; Miller, Jonathan; Lüders, Hans; Lhatoo, Samden D

    2015-06-01

    MRI-negative anterior cingulate epilepsy is a rare entity. Herein, we describe a case of MRI and functional imaging-negative intractable frontal lobe epilepsy in which, initially, secondary bilateral synchrony of surface and intracranial EEG and non-lateralizing semiology rendered identification of the epileptogenic zone difficult. A staged bilateral stereotactic EEG exploration revealed a very focal, putative ictal onset zone in the right anterior cingulate gyrus, as evidenced by interictal and ictal high-frequency oscillations (at 250Hz) and induction of seizures from the same electrode contacts by 50-Hz low-intensity cortical stimulation. This was subsequently confirmed by ILAE class 1 outcome following resection of the ictal onset and irritative zones. Histopathological examination revealed focal cortical dysplasia type 1b (ILAE Commission, 2011) as the cause of epilepsy. The importance of anatomo-electro-clinical correlation is illustrated in this case in which semiological and electrophysiological features pointed to the anatomical localization of a challenging, MRI-negative epilepsy. PMID:26056053

  9. Negative-tone 193-nm resists

    NASA Astrophysics Data System (ADS)

    Cho, Sungseo; Vander Heyden, Anthony; Byers, Jeff D.; Willson, C. Grant

    2000-06-01

    A great deal of progress has been made in the design of single layer positive tone resists for 193 nm lithography. Commercial samples of such materials are now available from many vendors. The patterning of certain levels of devices profits from the use of negative tone resists. There have been several reports of work directed toward the design of negative tones resists for 193 nm exposure but, none have performed as well as the positive tone systems. Polymers with alicyclic structures in the backbone have emerged as excellent platforms from which to design positive tone resists for 193 nm exposure. We now report the adaptation of this class of polymers to the design of high performance negative tone 193 nm resists. New systems have been prepared that are based on a polarity switch mechanism for modulation of the dissolution rate. The systems are based on a polar, alicyclic polymer backbone that includes a monomer bearing a glycol pendant group that undergoes the acid catalyzed pinacol rearrangement upon exposure and bake to produce the corresponding less polar ketone. This monomer was copolymerized with maleic anhydride and a norbornene bearing a bis-trifluoromethylcarbinol. The rearrangement of the copolymer was monitored by FT-IR as a function of temperature. The synthesis of the norbornene monomers will be presented together with characterization of copolymers of these monomers with maleic anhydride. The lithographic performance of the new resist system will also be presented.

  10. Negative Halogen Ions for Fusion Applications

    SciTech Connect

    Grisham, L.R.; Kwan, J.W.; Hahto, S.K.; Hahto, S.T.; Leung, K.N.; Westenskow, G.

    2006-01-01

    Over the past quarter century, advances in hydrogen negative ion sources have extended the usable range of hydrogen isotope neutral beams to energies suitable for large magnetically confined fusion devices. Recently, drawing upon this experience, negative halogen ions have been proposed as an alternative to positive ions for heavy ion fusion drivers in inertial confinement fusion, because electron accumulation would be prevented in negative ion beams, and if desired, the beams could be photo-detached to neutrals. This paper reports the results of an experiment comparing the current density and beam emittance of Cl+ and Cl- extracted from substantially ion-ion plasmas with that of Ar+ extracted from an ordinary electron-ion plasma, all using the same source, extractor, and emittance scanner. At similar discharge conditions, the Cl- current was typically 85 – 90% of the positive chlorine current, with an e-/ Cl- ratio as low as seven without grid magnets. The Cl- was as much as 76% of the Ar+ current from a discharge with the same RF drive. The minimum normalized beam emittance and inferred ion temperatures of Cl+, Cl-, and Ar+ were all similar, so the current density and optical quality of Cl- appear as suitable for heavy ion fusion driver applications as a positive noble gas ion of similar mass. Since F, I, and Br should all behave similarly in an ion source, they should also be suitable as driver beams.

  11. Negative excess noise in gated quantum wires

    SciTech Connect

    Dolcini, F.; Trauzettel, B.; Safi, I.; Grabert, H.

    2009-04-23

    The electrical current noise of a quantum wire is expected to increase with increasing applied voltage. We show that this intuition can be wrong. Specifically, we consider a single channel quantum wire with impurities and with a capacitive coupling to a metallic gate, and find that its excess noise, defined as the change in the noise caused by the finite voltage, can be negative at zero temperature. This feature is present both for large (c>>c{sub q}) and small (c<>c{sub q}, negativity of the excess noise can occur at finite frequency when the transmission coefficients are energy dependent, i.e. in the presence of Fabry-Perot resonances or band curvature. In the opposite regime c < or approx. c{sub q}, a non trivial voltage dependence of the noise arises even for energy independent transmission coefficients: at zero frequency the noise decreases with voltage as a power law when cnegative excess noise are present due to Andreev-type resonances.

  12. The Negative Effects of Volatile Sulphur Compounds.

    PubMed

    Milella, Lisa

    2015-01-01

    Oral malodor has been studied extensively in humans but not necessarily to the same degree in our veterinary patients where malodor constitutes a significant problem. Breath malodor may originate from the mouth, or from an extra oral source, originating from other organ systems such as gastrointestinal, respiratory, or even systemic disease. Oral malodor is a result of microbial metabolism of exogenous and endogenous proteinaceous substrates leading to the production of compounds such as indole, skatole, tyramine, cadaverine, puterescine, mercaptans, and sulphides. Volatile sulphur compounds have been shown to be the main cause of oral malodor. Although most clients perceive oral malodor to be primarily a cosmetic problem, there is an increasing volume of evidence in human dental literature demonstrating that volatile sulphur compounds produced by bacteria, even at low concentrations, are toxic to tissues and play a role in the pathogenesis of periodontitis. This article reviews the current available literature in human dentistry looking at these negative effects. No veterinary studies have been conducted looking at the negative effects of volatile sulphur compounds specifically, but as this article highlights, we should be aware of the potential negative effects of volatile sulphur compounds and consider this an area of future research. PMID:26415386

  13. Negative ion states of sulfur hexafluoride

    SciTech Connect

    Chen, E.C.M.; Shuie, L.; Desai D'sa, E.; Batten, C.F.; Wentworth, W.E.

    1988-04-15

    The reaction of SF/sub 6/ with thermal electrons has been studied in a Ni-63 atmospheric pressure ionization source for a quadrupole mass spectrometer (API/MS). The major ions that are observed are the parent negative ion (SF/sup -//sub 6/) and the parent minus a fluorine atom (SF/sup -//sub 5/). The ratio of (SF/sup -//sub 5/)/(SF/sup -//sub 6/) is highly temperature dependent above 500 K. The dissociation energy of the ground state negative ion into SF/sup -//sub 5/ and F has been determined to be 1.35 +- 0.1 eV. This gives values of 3.8 +- 0.15 eV for the electron affinity of SF/sub 5/ and 1.15 +- 0.15 eV for the electron affinity of SF/sub 6/. The negative ion states of sulfur hexafluoride have been described by ''pseudo-two-dimensional'' Morse potentials calculated using experimental data.

  14. Negative Stress Margins - Are They Real?

    NASA Technical Reports Server (NTRS)

    Raju, Ivatury S.; Lee, Darlene S.; Mohaghegh, Michael

    2011-01-01

    Advances in modeling and simulation, new finite element software, modeling engines and powerful computers are providing opportunities to interrogate designs in a very different manner and in a more detailed approach than ever before. Margins of safety are also often evaluated using local stresses for various design concepts and design parameters quickly once analysis models are defined and developed. This paper suggests that not all the negative margins of safety evaluated are real. The structural areas where negative margins are frequently encountered are often near stress concentrations, point loads and load discontinuities, near locations of stress singularities, in areas having large gradients but with insufficient mesh density, in areas with modeling issues and modeling errors, and in areas with connections and interfaces, in two-dimensional (2D) and three-dimensional (3D) transitions, bolts and bolt modeling, and boundary conditions. Now, more than ever, structural analysts need to examine and interrogate their analysis results and perform basic sanity checks to determine if these negative margins are real.

  15. IMMUNOHISTOCHEMICAL DIFFERENTIATION OF TRIPLE NEGATIVE BREAST CANCER.

    PubMed

    Lesar, Miroslav; Stanec, Mladen; Lesar, Nikola; Vrdoljak, Danko Velimir; Zore, Zvonimir; Banović, Marija; Brozović, Gordana

    2016-03-01

    Based on immunohistochemical staining for the basal markers cytokeratin 5/6 (CK 5/6), cytokeratin 14 (CK 14) and P-cadherin, triple negative tumors (TNT) are divided into two groups: 1) basal-like (BL) positive for one or all three markers; and 2) non basal-like (NBL) negative for all three markers. Even though the different origin of the cells of these two types of tumors implies different biological properties, they had been treated as one entity until recently. This paper analyzes TNT collected from 150 patients and distributed into two groups according to the results of immunohistochemical analysis, i.e. BL 116 (77.3%) and NBL 34 (22.67%). In this study, CK 5/6, CK 14 and P-cadherin were used as markers for identifying BL tumors. The immunohistochemical reaction was positive for CK 5/6 in 37%, for CK 14 in 50.86% and for P-cadherin in 68.34% of cases. The subclassification of triple negative breast cancer using the basal markers CK 5/6, CK 14 and P-cadherin has enabled identification of BL and NBL breast cancers in a proportion that is in line with the only accurate analysis of TNT gene expression. Using the mentioned combination of markers in daily practice is easy to perform and economically affordable. PMID:27333711

  16. Simulation Based on Ion Propulsion Rocket System with Using Negative ion - Negative Ion Pair Techniques

    NASA Astrophysics Data System (ADS)

    Sathiyavel, C.

    2016-07-01

    Ion propulsion rocket system is expected to become popular with the development of ion-ion pair techniques because of their stimulated of low propellant, Design of Thrust range is 1N with low electric power and high efficiency. A Negative ion-Negative ion pair of ion propulsion rocket system is proposed in this work .Negative Ion Based Rocket system consists of three parts 1.ionization chamber 2. Repulsion force and ion accelerator 3. Exhaust of Nozzle. The Negative ions from electro negatively gas are produced by attachment of the gas ,such as chlorine with electron emitted from a Electron gun ionization chamber. The formulate of large stable negative ion is achievable in chlorine gas with respect to electron affinity (∆E). The electron affinity is a measure of the energy change when an electron is added to a neutral atom to form a negative ion. When a neutral chlorine atom in the gaseous form picks up an electron to form a Cl- ion, it releases energy of 349 kJ/mol or 3.6 ev/atom. It is said to have an electron affinity of -349 kJ/mol ,the negative sign indicating that energy is released during this process .The mechanisms of attachment involve the formation of intermediate states. In that reason for , the highly repulsive force created between the same negative ions. The distance between same negative ions is important for the evaluate of the rocket thrust and is also determined by the exhaust velocity of the propellant. The mass flow rate of propellant is achieved by the ratio of total mass of the propellant (Kg) needed for operation to time period(s). Accelerate the Negative ions to a high velocity in the thrust vector direction with a significantly intense Magnetic field and the exhaust of negative ions through Nozzle. The simulation of the ion propulsion system has been carried out by MATLAB. By comparing the simulation results with the theoretical and previous results, we have found that the proposed method is achieved of thrust value with estimated

  17. The effectiveness of net negative carbon dioxide emissions in reversing anthropogenic climate change

    NASA Astrophysics Data System (ADS)

    Tokarska, Katarzyna B.; Zickfeld, Kirsten

    2015-09-01

    Artificial removal of CO2 from the atmosphere (also referred to as negative emissions) has been proposed as a means to restore the climate system to a desirable state, should the impacts of climate change become ‘dangerous’. Here we explore whether negative emissions are indeed effective in reversing climate change on human timescales, given the potentially counteracting effect of natural carbon sinks and the inertia of the climate system. We designed a range of CO2 emission scenarios, which follow a gradual transition to a zero-carbon energy system and entail implementation of various amounts of net-negative emissions at technologically plausible rates. These scenarios are used to force an Earth System Model of intermediate complexity. Results suggest that while it is possible to revert to a desired level of warming (e.g. 2 °C above pre-industrial) after different levels of overshoot, thermosteric sea level rise is not reversible for at least several centuries, even under assumption of large amounts of negative CO2 emissions. During the net-negative emission phase, artificial CO2 removal is opposed by CO2 outgassing from natural carbon sinks, with the efficiency of CO2 removal—here defined as the drop in atmospheric CO2 per unit negative emission—decreasing with the total amount of negative emissions.

  18. Negative transcriptional regulation of the interferon-gamma promoter by glucocorticoids and dominant negative mutants of c-Jun.

    PubMed

    Cippitelli, M; Sica, A; Viggiano, V; Ye, J; Ghosh, P; Birrer, M J; Young, H A

    1995-05-26

    Interferon-gamma (IFN-gamma) is an immunoregulatory cytokine expressed in large granular lymphocytes and T cells. However, the molecular mechanisms underlying IFN-gamma gene transcription have not been fully defined. Here, we analyze the mechanisms responsible for the inhibition of IFN-gamma promoter activity by the glucocorticoid hormone dexamethasone. Cotransfection assays performed in Jurkat T cells demonstrated that the activity of the initial 108 base pairs of the IFN-gamma promoter was down-regulated in the presence of dexamethasone. Furthermore, utilizing electrophoretic mobility shift analysis, we identified activator protein 1 AP-1-cAMP response element binding protein-activating transcription factor (CREB-ATF) binding elements situated in positions of the IFN-gamma promoter previously identified as essential for promoter activity. Moreover, dominant negative mutants of the c-Jun proto-oncogene were able to mimic the same down-regulatory effect exerted by dexamethasone, and mutations that abolished the binding of the AP-1 CREB-ATF factors were able to block the glucocorticoid effect. These results suggest a model involving the inhibition of IFN-gamma AP-1 CREB-ATF DNA binding complexes as one of the mechanisms involved in the negative regulatory action of glucocorticoids on IFN-gamma gene expression and support the relevance of AP-1 CREB-ATF binding factors during the transcriptional activation of the IFN-gamma promoter in T cells. PMID:7759501

  19. Complex analysis of features of the ionic wind from a negative-polarity corona discharge

    NASA Astrophysics Data System (ADS)

    Ashikhmin, I. A.; Samusenko, A. V.; Stishkov, Yu. K.; Yakovlev, V. V.

    2015-11-01

    We perform computer simulation of the ionic wind in the point-torus and sphere-torus electrode systems taking into account the presence of electrons in the outer region of the corona discharge. The results of computation are compared with experimental velocity fields of air and the current-voltage characteristics. The velocity fields are recorded using laser anemometry of visualizing particles.

  20. Temperate Mountain Forest Biodiversity under Climate Change: Compensating Negative Effects by Increasing Structural Complexity

    PubMed Central

    Braunisch, Veronika; Coppes, Joy; Arlettaz, Raphaël; Suchant, Rudi; Zellweger, Florian; Bollmann, Kurt

    2014-01-01

    Species adapted to cold-climatic mountain environments are expected to face a high risk of range contractions, if not local extinctions under climate change. Yet, the populations of many endothermic species may not be primarily affected by physiological constraints, but indirectly by climate-induced changes of habitat characteristics. In mountain forests, where vertebrate species largely depend on vegetation composition and structure, deteriorating habitat suitability may thus be mitigated or even compensated by habitat management aiming at compositional and structural enhancement. We tested this possibility using four cold-adapted bird species with complementary habitat requirements as model organisms. Based on species data and environmental information collected in 300 1-km2 grid cells distributed across four mountain ranges in central Europe, we investigated (1) how species’ occurrence is explained by climate, landscape, and vegetation, (2) to what extent climate change and climate-induced vegetation changes will affect habitat suitability, and (3) whether these changes could be compensated by adaptive habitat management. Species presence was modelled as a function of climate, landscape and vegetation variables under current climate; moreover, vegetation-climate relationships were assessed. The models were extrapolated to the climatic conditions of 2050, assuming the moderate IPCC-scenario A1B, and changes in species’ occurrence probability were quantified. Finally, we assessed the maximum increase in occurrence probability that could be achieved by modifying one or multiple vegetation variables under altered climate conditions. Climate variables contributed significantly to explaining species occurrence, and expected climatic changes, as well as climate-induced vegetation trends, decreased the occurrence probability of all four species, particularly at the low-altitudinal margins of their distribution. These effects could be partly compensated by modifying single vegetation factors, but full compensation would only be achieved if several factors were changed in concert. The results illustrate the possibilities and limitations of adaptive species conservation management under climate change. PMID:24823495

  1. Negative differential conductivity in quantum well with complex potential profile for electron-phonon scattering

    NASA Astrophysics Data System (ADS)

    Figarova, S. R.; Hasiyeva, G. N.; Figarov, V. R.

    2016-04-01

    The effect of phonon scattering on electrical conductivity (EC) of 2D electron gas in quantum well (QW) systems with a complicated potential profile is described. Dependence of QW electrical conductivity on QW parameters (such as QW width, Fermi level positions etc.) when phonon scattering is employed has been calculated. NDC in EC when it varies with width of the QW has been found.

  2. Spin dynamics in the negatively charged terbium (III) bis-phthalocyaninato complex.

    PubMed

    Branzoli, Francesca; Carretta, Pietro; Filibian, Marta; Zoppellaro, Giorgio; Graf, Michael J; Galan-Mascaros, Jose R; Fuhr, Olaf; Brink, Susan; Ruben, Mario

    2009-04-01

    The experimental and theoretical study of the electron spin dynamics in the anionic form of a single-ion molecule magnet (SIMM), the bis-phthalocyaninato terbium (III) molecule [Pc(2)Tb](-)[TBA](+), has been addressed by means of solid state (1)H NMR spectroscopy. The magnetic properties of the caged Tb(3+) metal center were investigated in a series of diamagnetically diluted preparations, where the excess of tetrabutylamonium bromide ([TBA]Br)(n) salt was used as diamagnetic matrix complement. We found that a high temperature activated spin dynamics characterizes the systems, which involved phonon-assisted transitions among the crystal field levels in qualitative agreements with literature results. However, the activation barriers in these processes range from 641 cm(-1) for the diamagnetically diluted samples to 584 cm(-1) for those undiluted; thus, they exhibit barriers 2-3 times larger than witnessed in earlier (230 cm(-1)) reports (e.g., Ishikawa, N.; Sugita, M.; Ishikawa, T.; Koshihara, S.; Kaizu, Y. J. Am. Chem. Soc. 2003, 125, 8694-8695). At cryogenic temperatures, fluctuations are driven by tunneling processes between the m = +6 and -6 low-energy levels. We found that the barrier Delta and the tunneling rates change from sample to sample and especially the diamagnetically diluted [Pc(2)Tb](-) molecules appear affected by the sample's magneto/thermal history. These observations emphasize that matrix arrangements around [Pc(2)Tb](-) can appreciably alter the splitting of the crystal field levels, its symmetry, and hence, the spin dynamics. Therefore, understanding how small differences in molecular surroundings (as for instance occurring by depositing on surfaces) can trigger substantial modifications in the SIMM property is of utmost importance for the effective operation of such molecules for single-molecule data storage, for example. PMID:19275145

  3. SMN and coilin negatively regulate dyskerin association with telomerase RNA

    PubMed Central

    Poole, Aaron R.

    2016-01-01

    ABSTRACT Telomerase is a ribonucleoprotein comprising telomerase RNA and associated proteins. The formation of the telomerase holoenzyme takes place in the Cajal body (CB), a subnuclear domain that participates in the formation of ribonucleoproteins. CBs also contribute to the delivery of telomerase to telomeres. The protein WRAP53 is enriched within the CB and is instrumental for the targeting of telomerase RNA to CBs. Two other CB proteins, SMN and coilin, are also suspected of taking part in some aspect of telomerase biogenesis. Here we demonstrate newly discovered associations between SMN and coilin with telomerase components, and further show that reduction of SMN or coilin is correlated with increased association of telomerase RNA with one these components, dyskerin. These findings argue that SMN and coilin may negatively regulate the formation of telomerase. Furthermore, clinically defined SMN mutants found in individuals with spinal muscular atrophy are altered in their association with telomerase complex proteins. Additionally, we observe that a coilin derivative also associates with dyskerin, and the amount of this protein in the complex is regulated by SMN, WRAP53 and coilin levels. Collectively, our findings bolster the link between SMN, coilin and the coilin derivative in the biogenesis of telomerase. PMID:27215323

  4. SMN and coilin negatively regulate dyskerin association with telomerase RNA.

    PubMed

    Poole, Aaron R; Hebert, Michael D

    2016-01-01

    Telomerase is a ribonucleoprotein comprising telomerase RNA and associated proteins. The formation of the telomerase holoenzyme takes place in the Cajal body (CB), a subnuclear domain that participates in the formation of ribonucleoproteins. CBs also contribute to the delivery of telomerase to telomeres. The protein WRAP53 is enriched within the CB and is instrumental for the targeting of telomerase RNA to CBs. Two other CB proteins, SMN and coilin, are also suspected of taking part in some aspect of telomerase biogenesis. Here we demonstrate newly discovered associations between SMN and coilin with telomerase components, and further show that reduction of SMN or coilin is correlated with increased association of telomerase RNA with one these components, dyskerin. These findings argue that SMN and coilin may negatively regulate the formation of telomerase. Furthermore, clinically defined SMN mutants found in individuals with spinal muscular atrophy are altered in their association with telomerase complex proteins. Additionally, we observe that a coilin derivative also associates with dyskerin, and the amount of this protein in the complex is regulated by SMN, WRAP53 and coilin levels. Collectively, our findings bolster the link between SMN, coilin and the coilin derivative in the biogenesis of telomerase. PMID:27215323

  5. IKKα negatively regulates ASC-dependent inflammasome activation.

    PubMed

    Martin, Bradley N; Wang, Chenhui; Willette-Brown, Jami; Herjan, Tomasz; Gulen, Muhammet F; Zhou, Hao; Bulek, Katarzyna; Franchi, Luigi; Sato, Takashi; Alnemri, Emad S; Narla, Goutham; Zhong, Xiao-Ping; Thomas, James; Klinman, Dennis; Fitzgerald, Katherine A; Karin, Michael; Nuñez, Gabriel; Dubyak, George; Hu, Yinling; Li, Xiaoxia

    2014-01-01

    The inflammasomes are multiprotein complexes that activate caspase-1 in response to infections and stress, resulting in the secretion of pro-inflammatory cytokines. Here we report that IκB kinase α (IKKα) is a critical negative regulator of apoptosis-associated specklike protein containing a C-terminal caspase-activation-andrecruitment (CARD) domain (ASC)-dependent inflammasomes. IKKα controls the inflammasome at the level of the adaptor ASC, which interacts with IKKα in the nucleus of resting macrophages in an IKKα kinase-dependent manner. Loss of IKKα kinase activity results in inflammasome hyperactivation. Mechanistically, the downstream nuclear effector IKK-related kinase (IKKi) facilitates translocation of ASC from the nucleus to the perinuclear area during inflammasome activation. ASC remains under the control of IKKα in the perinuclear area following translocation of the ASC/IKKα complex. Signal 2 of NLRP3 activation leads to inhibition of IKKα kinase activity through the recruitment of PP2A, allowing ASC to participate in NLRP3 inflammasome assembly. Taken together, these findings reveal a IKKi-IKKα-ASC axis that serves as a common regulatory mechanism for ASC-dependent inflammasomes. PMID:25266676

  6. IKKα negatively regulates ASC-dependent inflammasome activation

    PubMed Central

    Martin, Bradley N.; Wang, Chenhui; Willette-Brown, Jami; Herjan, Tomasz; Gulen, Muhammet F.; Zhou, Hao; Bulek, Katarzyna; Franchi, Luigi; Sato, Takashi; Narla, Goutham; Zhong, Xiao-Ping; Thomas, James; Klinman, Dennis; Fitzgerald, Katherine A.; Karin, Michael; Nuñez, Gabriel; Dubyak, George; Hu, Yinling; Li, Xiaoxia

    2014-01-01

    The inflammasomes are multiprotein complexes that activate caspase-1 in response to infections and stress, resulting in the secretion of pro-inflammatory cytokines. Here we report that IKKα is a critical negative regulator of ASC-dependent inflammasomes. IKKα controls the inflammasome at the level of the adaptor ASC, which interacts with IKKα in the nucleus of resting macrophages in an IKKα kinase-dependent manner. Loss of IKKα kinase activity results in inflammasome hyperactivation. Mechanistically, the downstream nuclear effector IKKi facilitates translocation of ASC from the nucleus to the perinuclear area during inflammasome activation. ASC remains under the control of IKKα in the perinuclear area following translocation of the ASC/IKKα complex. Signal 2 of NLRP3 activation leads to inhibition of IKKα kinase activity through the recruitment of PP2A, allowing ASC to participate in NLRP3 inflammasome assembly. Taken together, these findings reveal a IKKi-IKKα-ASC axis that serves as a common regulatory mechanism for ASC-dependent inflammasomes. PMID:25266676

  7. On State Complexes and Special Cube Complexes

    ERIC Educational Resources Information Center

    Peterson, Valerie J.

    2009-01-01

    This thesis presents the first steps toward a classification of non-positively curved cube complexes called state complexes. A "state complex" is a configuration space for a "reconfigurable system," i.e., an abstract system in which local movements occur in some discrete manner. Reconfigurable systems can be used to describe, for example,…

  8. EDITORIAL: Negative ion based neutral beam injection

    NASA Astrophysics Data System (ADS)

    Hemsworth, R. S.

    2006-06-01

    It is widely recognized that neutral beam injection (NBI), i.e. the injection of high energy, high power, beams of H or D atoms, is a flexible and reliable system that has been the main heating system on a large variety of fusion devices, and NBI has been chosen as one of the three heating schemes of the International Tokomak Reactor (ITER). To date, all the NBI systems but two have been based on the neutralization (in a simple gas target) of positive hydrogen or deuterium ions accelerated to <100 keV/nucleon. Above that energy the neutralization of positive ions falls to unacceptably low values, and higher energy neutral beams have to be created by the neutralization of accelerated negative ions (in a simple gas target), as this remains high (approx60%) up to >1 MeV/nucleon. Unfortunately H- and D- are difficult to create, and the very characteristic that makes them attractive, the ease with which the electron is detached from the ion, means that it is difficult to create high concentrations or fluxes of them, and it is difficult to avoid substantial, collisional, losses in the extraction and acceleration processes. However, there has been impressive progress in negative ion sources and accelerators over the past decade, as demonstrated by the two pioneering, operational, multi-megawatt, negative ion based, NBI systems at LHD (180 keV, H0) and JT-60U (500 keV, D0), both in Japan. Nevertheless, the system proposed for ITER represents a substantial technological challenge as an increase is required in beam energy, to 1 MeV, D0, accelerated ion (D-) current, to 40 A, accelerated current density, 200 A m-2 of D-, and pulse length, to 1 h. At the Fourth IAEA Technical Meeting on Negative Ion Based Neutral Beam Injectors, hosted by the Consorzio RFX, Padova, Italy, 9-11 May 2005, the status of the R&D aimed at the realization of the injectors for ITER was presented. Because of the importance of this development to the success of the ITER project, participants at that

  9. A novel pathway for outer membrane protein biogenesis in Gram‐negative bacteria

    PubMed Central

    Jeeves, Mark

    2015-01-01

    Summary The understanding of the biogenesis of the outer membrane of Gram‐negative bacteria is of critical importance due to the emergence of bacteria that are becoming resistant to available antibiotics. A problem that is most serious for Gram‐negative bacteria, with essentially few antibiotics under development or likely to be available for clinical use in the near future. The understanding of the Gram‐negative bacterial outer membrane is therefore critical to developing new antimicrobial agents, as this membrane makes direct contact with the external milieu, and the proteins present within this membrane are the instruments of microbial warfare, playing key roles in microbial pathogenesis, virulence and multidrug resistance. To date, a single outer membrane complex has been identified as essential for the folding and insertion of proteins into the outer membrane, this is the β‐barrel assembly machine (BAM) complex, which in some cases is supplemented by the Translocation and Assembly Module (TAM). In this issue of Molecular Microbiology, Dunstan et al. have identified a novel pathway for the insertion of a subset of integral membrane proteins into the Gram‐negative outer membrane that is independent of the BAM complex and TAM. PMID:26059329

  10. A novel pathway for outer membrane protein biogenesis in Gram-negative bacteria.

    PubMed

    Jeeves, Mark; Knowles, Timothy J

    2015-08-01

    The understanding of the biogenesis of the outer membrane of Gram-negative bacteria is of critical importance due to the emergence of bacteria that are becoming resistant to available antibiotics. A problem that is most serious for Gram-negative bacteria, with essentially few antibiotics under development or likely to be available for clinical use in the near future. The understanding of the Gram-negative bacterial outer membrane is therefore critical to developing new antimicrobial agents, as this membrane makes direct contact with the external milieu, and the proteins present within this membrane are the instruments of microbial warfare, playing key roles in microbial pathogenesis, virulence and multidrug resistance. To date, a single outer membrane complex has been identified as essential for the folding and insertion of proteins into the outer membrane, this is the β-barrel assembly machine (BAM) complex, which in some cases is supplemented by the Translocation and Assembly Module (TAM). In this issue of Molecular Microbiology, Dunstan et al. have identified a novel pathway for the insertion of a subset of integral membrane proteins into the Gram-negative outer membrane that is independent of the BAM complex and TAM. PMID:26059329

  11. The use of negative pressure wound therapy for random local flaps at the ankle region.

    PubMed

    Goldstein, Jesse A; Iorio, Matthew L; Brown, Benjamin; Attinger, Christopher E

    2010-01-01

    Local random flaps are seldom used for reconstruction of complex ankle wounds because of concern for flap failure attributable to vascular compromise and tissue edema. Negative pressure wound therapy has been shown to improve perfusion and limit tissue edema. The objective of this study was to demonstrate the utility of negative pressure wound therapy in improving outcomes for local flaps of the ankle. Ten consecutive patients presenting with complex ankle wounds and reconstructed using local flaps were treated with negative pressure wound therapy postoperatively. Type of flap, immediate and long-term outcomes, and complications were assessed. Seventeen local flaps were performed on 10 patients to reconstruct their ankle wounds. Mean follow up was 88 days. All flaps healed without tissue compromise or necrosis. Only one partial dehiscence and no infections were observed. This study demonstrates that negative pressure therapy may contribute to the viability of random local flaps by decreasing venous congestion. Our experience using negative pressure wound therapy on local flaps suggests that it may serve as a useful adjunct to ensure successful closure of high-risk wounds. PMID:20801691

  12. Negative Gaussian curvature from induced metric changes.

    PubMed

    Modes, Carl D; Warner, Mark

    2015-07-01

    We revisit the light or heat-induced changes in topography of initially flat sheets of a solid that elongate or contract along patterned in-plane director fields. For radial or azimuthal directors, negative Gaussian curvature is generated-so-called "anticones." We show that azimuthal material displacements are required for the distorted state to be stretch free and bend minimizing. The resultant shapes are smooth and asterlike and can become reentrant in the azimuthal coordinate for large deformations. We show that care is needed when considering elastomers rather than glasses, although the former offer huge deformations. PMID:26274106

  13. Growing Networks with Positive and Negative Links

    NASA Astrophysics Data System (ADS)

    Dech, Corynne; Antwi, Shadrack; Shaw, Leah

    Scale-free networks grown via preferential attachment have been used to model real-world networks such as the Internet, citation networks, and social networks. Here we investigate signed scale-free networks where an edge represents a positive or negative connection. We present analytic results and simulation for a growing signed network model. We compare the signed network to an unsigned scale-free network. We discuss several options for preferential attachment in a signed network that could be further adapted to model the accumulation of links over time in real-world signed networks.

  14. Negative Selection Algorithm for Aircraft Fault Detection

    NASA Technical Reports Server (NTRS)

    Dasgupta, D.; KrishnaKumar, K.; Wong, D.; Berry, M.

    2004-01-01

    We investigated a real-valued Negative Selection Algorithm (NSA) for fault detection in man-in-the-loop aircraft operation. The detection algorithm uses body-axes angular rate sensory data exhibiting the normal flight behavior patterns, to generate probabilistically a set of fault detectors that can detect any abnormalities (including faults and damages) in the behavior pattern of the aircraft flight. We performed experiments with datasets (collected under normal and various simulated failure conditions) using the NASA Ames man-in-the-loop high-fidelity C-17 flight simulator. The paper provides results of experiments with different datasets representing various failure conditions.

  15. Visual mismatch negativity: a predictive coding view.

    PubMed

    Stefanics, Gábor; Kremláček, Jan; Czigler, István

    2014-01-01

    An increasing number of studies investigate the visual mismatch negativity (vMMN) or use the vMMN as a tool to probe various aspects of human cognition. This paper reviews the theoretical underpinnings of vMMN in the light of methodological considerations and provides recommendations for measuring and interpreting the vMMN. The following key issues are discussed from the experimentalist's point of view in a predictive coding framework: (1) experimental protocols and procedures to control "refractoriness" effects; (2) methods to control attention; (3) vMMN and veridical perception. PMID:25278859

  16. Single-resonator double-negative metamaterial

    DOEpatents

    Warne, Larry K.; Basilio, Lorena I.; Langston, William L.; Johnson, William A.; Ihlefeld, Jon; Ginn, III, James C.; Clem, Paul G.; Sinclair, Michael B.

    2016-06-21

    Resonances can be tuned in dielectric resonators in order to construct single-resonator, negative-index metamaterials. For example, high-contrast inclusions in the form of metallic dipoles can be used to shift the first electric resonance down (in frequency) to the first magnetic resonance, or alternatively, air splits can be used to shift the first magnetic resonance up (in frequency) near the first electric resonance. Degenerate dielectric designs become especially useful in infrared- or visible-frequency applications where the resonator sizes associated with the lack of high-permittivity materials can become of sufficient size to enable propagation of higher-order lattice modes in the resulting medium.

  17. Mechanism of branching in negative ionization fronts.

    PubMed

    Arrayás, Manuel; Fontelos, Marco A; Trueba, José L

    2005-10-14

    When a strong electric field is applied to nonconducting matter, narrow channels of plasma called streamers may form. Branchlike patterns of streamers have been observed in anode directed discharges. We explain a mechanism for branching as the result of a balance between the destabilizing effect of impact ionization and the stabilizing effect of electron diffusion on ionization fronts. The dispersion relation for transversal perturbation of a planar negative front is obtained analytically when the ratio D between the electron diffusion coefficient and the intensity of the externally imposed electric field is small. We estimate the spacing lambda between streamers and deduce a scaling law lambda approximately D(1/3). PMID:16241810

  18. Negative reinforcement impairs overnight memory consolidation.

    PubMed

    Stamm, Andrew W; Nguyen, Nam D; Seicol, Benjamin J; Fagan, Abigail; Oh, Angela; Drumm, Michael; Lundt, Maureen; Stickgold, Robert; Wamsley, Erin J

    2014-11-01

    Post-learning sleep is beneficial for human memory. However, it may be that not all memories benefit equally from sleep. Here, we manipulated a spatial learning task using monetary reward and performance feedback, asking whether enhancing the salience of the task would augment overnight memory consolidation and alter its incorporation into dreaming. Contrary to our hypothesis, we found that the addition of reward impaired overnight consolidation of spatial memory. Our findings seemingly contradict prior reports that enhancing the reward value of learned information augments sleep-dependent memory processing. Given that the reward followed a negative reinforcement paradigm, consolidation may have been impaired via a stress-related mechanism. PMID:25320351

  19. Lower body negative pressure, experiment M092

    NASA Technical Reports Server (NTRS)

    Johnson, R. L.; Nicogossian, A. E.; Jackson, M. M.; Hoffler, G. W.; Wolthuis, R. A.

    1973-01-01

    Evaluation of orthostatic intolerance has been achieved by the use of lower body negative pressure (LBNP). The LBNP technique, though independent of gravity, simulates its effect by exposing the legs and the lower abdomen to reduced ambient pressures. This LBNP experiment, conducted during the 56-day simulation of the Skylab environment, was designed to supply baseline information on cardiovascular responses to periodic orthostatic stress. Impaired orthostatic tolerance, manifested by the increased heart rate, diminished systolic and pulse pressure, and increased tendency to syncope in the upright position, or during LBNP, was not observed in this experiment.

  20. Negative impact of manganese on honeybee foraging

    PubMed Central

    Søvik, Eirik; Perry, Clint J.; LaMora, Angie; Barron, Andrew B.; Ben-Shahar, Yehuda

    2015-01-01

    Anthropogenic accumulation of metals such as manganese is a well-established health risk factor for vertebrates. By contrast, the long-term impact of these contaminants on invertebrates is mostly unknown. Here, we demonstrate that manganese ingestion alters brain biogenic amine levels in honeybees and fruit flies. Furthermore, we show that manganese exposure negatively affects foraging behaviour in the honeybee, an economically important pollinator. Our findings indicate that in addition to its direct impact on human health, the common industrial contaminant manganese might also have indirect environmental and economical impacts via the modulation of neuronal and behavioural functions in economically important insects. PMID:25808001

  1. HIV-negative gay men at risk.

    PubMed

    1995-01-01

    According to a study conducted by the Gay and Lesbian Medical Association, HIV-negative gay and bisexual men are at great risk of becoming HIV-positive unless changes in prevention education are made. Investigators studied gay men in four cities and projected their chances of becoming infected with HIV. They found an infection rate of three percent per year for gay and bisexual men under thirty. Low self-esteem, peer pressure, and a need for intimacy were contributing factors to unsafe sexual behavior. PMID:11362379

  2. Scalar field collapse with negative cosmological constant

    NASA Astrophysics Data System (ADS)

    Baier, R.; Nishimura, H.; Stricker, S. A.

    2015-07-01

    The formation of black holes or naked singularities is studied in a model in which a homogeneous time-dependent scalar field with an exponential potential couples to four-dimensional gravity with negative cosmological constant. An analytic solution is derived and its consequences are discussed. The model depends only on one free parameter, which determines the equation of state and decides the fate of the spacetime. Without fine tuning the value of this parameter the collapse ends in a generic formation of a black hole or a naked singularity. The latter case violates the cosmic censorship conjecture.

  3. Visual mismatch negativity: a predictive coding view

    PubMed Central

    Stefanics, Gábor; Kremláček, Jan; Czigler, István

    2014-01-01

    An increasing number of studies investigate the visual mismatch negativity (vMMN) or use the vMMN as a tool to probe various aspects of human cognition. This paper reviews the theoretical underpinnings of vMMN in the light of methodological considerations and provides recommendations for measuring and interpreting the vMMN. The following key issues are discussed from the experimentalist's point of view in a predictive coding framework: (1) experimental protocols and procedures to control “refractoriness” effects; (2) methods to control attention; (3) vMMN and veridical perception. PMID:25278859

  4. Negative Ion Photoelectron Spectra of Halomethyl Anions

    NASA Astrophysics Data System (ADS)

    Vogelhuber, Kristen M.; Wren, Scott W.; McCoy, Anne B.; Ervin, Kent M.; Lineberger, W. Carl

    2009-06-01

    Halomethyl anions undergo a significant geometry change upon electron photodetachment, resulting in multiple extended vibrational progressions in the photoelectron spectra. The normal mode analysis that successfully models photoelectron spectra when geometry changes are modest is unable to reproduce the experimental data using physically reasonable parameters. A three-dimensional anharmonic coupled-mode analysis was employed to accurately reproduce the observed vibrational structure. We present the 364 nm negative ion photoelectron spectra of the halomethyl anions CHX_2^- and CDX_2^- (X = Cl, Br, I) and report electron affinities, vibrational frequencies, and geometries.

  5. The production and destruction of negative ions

    SciTech Connect

    Pegg, D.J.

    1993-01-01

    Single photon absorption-single electron detachment from few-electron atomic negative ions was studied. A crossed beam apparatus is being used to perform energy- and angle-resolved photoelectron spectroscopic measurements following photodetachment. Forward-directed electrons were collected and energy analyzed. The kinetic energies and yields of the photoelectrons were obtained by fitting the spectral peaks to Gaussian functions. Electron affinities, asymmetry parameters and cross sections are determined from these measurements. A ratio method in which the cross section for the ion of interest is measured relative to that of a reference ion was used. The study of the photodetachment of Li[sup [minus

  6. Does the negative binomial distribution add up?

    PubMed

    Grafen, A; Woolhouse, M E

    1993-12-01

    The negative binomial distribution (NBD) is widely used to describe the distribution of parasitic helminths in a number of host individuals and has proved a useful, though possibly overused, empirical and theoretical device. It is therefore important that the limits to the applicability of the NBD be clearly defined. In this paper, Alan Grafen and Mark Woolhouse consider applications of the NBD in situations where either the host or parasite population can be divided into subpopulations of different types (eg. by age, sex or genotype), and they describe the relationships between the frequency distributions relevant to the different subpopulations and those relevant to the total population. PMID:15463698

  7. BRCA mutation-negative women from hereditary breast and ovarian cancer families: a qualitative study of the BRCA-negative experience

    PubMed Central

    Bakos, Alexis D.; Hutson, Sadie P.; Loud, Jennifer T.; Peters, June A.; Giusti, Ruthann M.; Greene, Mark H.

    2009-01-01

    Background When women from families with a known BRCA1 or BRCA2 mutation test negative for the family mutation, it is assumed that they will transition their personal cancer risk perception from high to average risk. However, there are scant data regarding the experience of mutation-negative women after genetic testing disclosure, particularly related to the shift of risk perception from assumed mutation-positive to actual mutation-negative. This study was designed to explore cancer risk perception and the experience of being a mutation-negative woman within a known BRCA1 / 2 mutation-positive family. Methods We employed a qualitative descriptive design and convened a sample of 13 women who contributed in-depth, semi-structured telephone interviews (audio-recorded and transcribed verbatim) and performed qualitative content analysis with NVivo 2.0 software. Results Six major content areas emerged from interview data: (i) rationale for initial involvement in the breast imaging study, (ii) rationale for continued participation, (iii) experience of living in a multiple-case family, (iv) risk perception: the personal meaning of mutation-negative status, (v) opinions regarding cancer aetiology and (vi) communication patterns between mutation-negative and mutation-positive family members. Conclusions Living in a hereditary breast and ovarian cancer family is a complex experience that affects cognitive, emotional and social functioning. Our findings indicate that mutation-negative women may have unmet psychosocial needs that must be addressed by health-care professionals, particularly in the primary-care setting following genetic disclosure of a potentially reassuring result regarding their lack of the very high cancer risks associated with BRCA1 / 2 mutations. PMID:18816319

  8. Freeze or Flee? Negative Stimuli Elicit Selective Responding

    ERIC Educational Resources Information Center

    Estes, Zachary; Verges, Michelle

    2008-01-01

    Humans preferentially attend to negative stimuli. A consequence of this automatic vigilance for negative valence is that negative words elicit slower responses than neutral or positive words on a host of cognitive tasks. Some researchers have speculated that negative stimuli elicit a general suppression of motor activity, akin to the freezing…

  9. Carboplatin and Eribulin Mesylate in Triple Negative Breast Cancer Patients

    ClinicalTrials.gov

    2016-06-30

    Estrogen Receptor-negative Breast Cancer; HER2-negative Breast Cancer; Male Breast Cancer; Progesterone Receptor-negative Breast Cancer; Stage IA Breast Cancer; Stage IB Breast Cancer; Stage II Breast Cancer; Stage IIIA Breast Cancer; Stage IIIB Breast Cancer; Stage IIIC Breast Cancer; Triple-negative Breast Cancer

  10. Presupposition Processing and the (Re)activation of Negated Concepts

    ERIC Educational Resources Information Center

    Autry, Kevin S.; Levine, William H.

    2014-01-01

    Negated words take longer to recognize than non-negated words following sentences with negation, suggesting that negated concepts are less active. The present experiments tested the possibility that this reduced activation would not persist beyond immediate testing. Experiment 1 used a probe task and materials similar to those used in previous…

  11. Stressful Life Event Influences on Positive and Negative Psychological Functioning.

    ERIC Educational Resources Information Center

    McGowan, John R.; Cohen, Lawrence H.

    Some research has suggested that positive life events may interact with negative life events during periods of high stress to buffer the effects of negative events. The relationships among positive and negative life events and positive and negative psychological status were examined in an investigation of the direct and mediating effects of…

  12. Left-handed metamaterials operating in the visible: negative refraction and negative radiation pressure

    NASA Astrophysics Data System (ADS)

    Lezec, Henri

    2009-03-01

    Forty years ago, V. Veselago derived the electromagnetic properties of a hypothetical material having simultaneously-negative values of electric permittivity and magnetic permeability [1]. Such a material, denominated ``left-handed'', was predicted to exhibit a negative index of refraction, as well as a number of other counter-intuitive optical properties. For example, it was hypothesized that a perfect mirror illuminated with a plane wave would experience a negative radiation pressure (pull) when immersed in a left-handed medium, as opposed to the usual positive radiation pressure experienced when facing a dielectric medium such as air or glass. Since left-handed materials are not available in nature, considerable efforts are currently under way to implement them under the form of artificial ``metamaterials'' -- composite media with tailored bulk optical characteristics resulting from constituent structures which are smaller in both size and density than the effective wavelength in the medium. Here we show how surface-plasmon modes propagating in a stacked array of metal-insulator-metal (MIM) waveguides can be harnessed to yield a volumetric left-handed metamaterial characterized by an in-plane-isotropic negative index of refraction over a broad frequency range spanning the blue and green. By sculpting this material with a focused-ion beam we realize prisms and micro-cantilevers which we use to demonstrate, for the first time, (a) in-plane isotropic negative-refraction at optical frequencies, and (b) negative radiation pressure. We predict and experimentally verify a negative ``superpressure'', the magnitude of which exceeds the photon pressure experienced by a perfect mirror by more than a factor of two. 1) V. Veselago, Sov. Phys. Usp. 10, p.509 (1968).

  13. [Treatment of surgical wound dehiscence by topical negative pressure therapy: Clinical case].

    PubMed

    Fresno-García, Carmen; Alconero-Camarero, Ana Rosa; Fernández-Carro, Belén

    2015-01-01

    Topical negative pressure therapy is an alternative treatment for complex wounds that consists of the direct application of sub-atmospheric pressure, obtaining a number of effects that are beneficial for tissues, promoting the healing of both acute and chronic wounds and complementing surgical procedures. We report the case of a 75 year old man diagnosed with surgical wound dehiscence after a femorotibial bypass graft, who was hospitalized again with the aim to perform the implantation of a topical negative pressure therapy in the infected wound. We designed a care plan for this patient following the steps of the scientific method and basing ourselves on the NANDA, NIC, and NOC taxonomies. PMID:26183760

  14. Brand Suicide? Memory and Liking of Negative Brand Names.

    PubMed

    Guest, Duncan; Estes, Zachary; Gibbert, Michael; Mazursky, David

    2016-01-01

    Negative brand names are surprisingly common in the marketplace (e.g., Poison perfume; Hell pizza, and Monster energy drink), yet their effects on consumer behavior are currently unknown. Three studies investigated the effects of negative brand name valence on brand name memory and liking of a branded product. Study 1 demonstrates that relative to non-negative brand names, negative brand names and their associated logos are better recognised. Studies 2 and 3 demonstrate that negative valence of a brand name tends to have a detrimental influence on product evaluation with evaluations worsening as negative valence increases. However, evaluation is also dependent on brand name arousal, with high arousal brand names resulting in more positive evaluations, such that moderately negative brand names are equally as attractive as some non-negative brand names. Study 3 shows evidence for affective habituation, whereby the effects of negative valence reduce with repeated exposures to some classes of negative brand name. PMID:27023872

  15. Brand Suicide? Memory and Liking of Negative Brand Names

    PubMed Central

    Guest, Duncan; Estes, Zachary; Gibbert, Michael; Mazursky, David

    2016-01-01

    Negative brand names are surprisingly common in the marketplace (e.g., Poison perfume; Hell pizza, and Monster energy drink), yet their effects on consumer behavior are currently unknown. Three studies investigated the effects of negative brand name valence on brand name memory and liking of a branded product. Study 1 demonstrates that relative to non-negative brand names, negative brand names and their associated logos are better recognised. Studies 2 and 3 demonstrate that negative valence of a brand name tends to have a detrimental influence on product evaluation with evaluations worsening as negative valence increases. However, evaluation is also dependent on brand name arousal, with high arousal brand names resulting in more positive evaluations, such that moderately negative brand names are equally as attractive as some non-negative brand names. Study 3 shows evidence for affective habituation, whereby the effects of negative valence reduce with repeated exposures to some classes of negative brand name. PMID:27023872

  16. Negative Diffusion Over Many Synodic Periods

    NASA Astrophysics Data System (ADS)

    Lewis, Mark C.; Stewart, G. R.

    2011-04-01

    In previous work we have looked at the migration of ring particles due to collisions in moon wakes caused by passing a moon massive enough to induce a forced eccentricity on the order of 10^-5 or more. In these systems, particles move rapidly toward regions of higher density in a process we call negative diffusion. This process can cause the radial width of a particle distribution to drop by 90% or more in certain configurations. Our earlier work focused on a single pass by the moon to remove complications due to resonances. Here we will present longer simulations that follow the material for 100 synodic periods to demonstrate how this process can contain material over longer periods of time and how resonances with the moons impact the evolution of the distribution of particle semimajor axes. The exact nature of the evolution is complicated by the fact that particles not only move toward regions of higher density, but also climb up the eccentricity gradients induced by resonances. In addition, the exact placement of narrow bands of material relative to resonances alters the forced eccentricity and hence the effectiveness of the negative diffusion.

  17. Negative regulation and developmental competence in Aspergillus

    PubMed Central

    Lee, Mi-Kyung; Kwon, Nak-Jung; Lee, Im-Soon; Jung, Seunho; Kim, Sun-Chang; Yu, Jae-Hyuk

    2016-01-01

    Asexual development (conidiation) in the filamentous fungus Aspergillus nidulans is governed by orchestrated gene expression. The three key negative regulators of conidiation SfgA, VosA, and NsdD act at different control point in the developmental genetic cascade. Here, we have revealed that NsdD is a key repressor affecting the quantity of asexual spores in Aspergillus. Moreover, nullifying both nsdD and vosA results in abundant formation of the development specific structure conidiophores even at 12 h of liquid culture, and near constitutive activation of conidiation, indicating that acquisition of developmental competence involves the removal of negative regulation exerted by both NsdD and VosA. NsdD’s role in repressing conidiation is conserved in other aspergilli, as deleting nsdD causes enhanced and precocious activation of conidiation in Aspergillus fumigatus or Aspergillus flavus. In vivo NsdD-DNA interaction analyses identify three NsdD binding regions in the promoter of the essential activator of conidiation brlA, indicating a direct repressive role of NsdD in conidiation. Importantly, loss of flbC or flbD encoding upstream activators of brlA in the absence of nsdD results in delayed activation of brlA, suggesting distinct positive roles of FlbC and FlbD in conidiation. A genetic model depicting regulation of conidiation in A. nidulans is presented. PMID:27364479

  18. Universal corner contributions to entanglement negativity

    NASA Astrophysics Data System (ADS)

    Kim, Keun-Young; Niu, Chao; Pang, Da-Wei

    2016-09-01

    It has been realised that corners in entangling surfaces can induce new universal contributions to the entanglement entropy and Rényi entropy. In this paper we study universal corner contributions to entanglement negativity in three- and four-dimensional CFTs using both field theory and holographic techniques. We focus on the quantity χ defined by the ratio of the universal part of the entanglement negativity over that of the entanglement entropy, which may characterise the amount of distillable entanglement. We find that for most of the examples χ takes bigger values for singular entangling regions, which may suggest increase in distillable entanglement. However, there also exist counterexamples where distillable entanglement decreases for singular surfaces. We also explore the behaviour of χ as the coupling varies and observe that for singular entangling surfaces, the amount of distillable entanglement is mostly largest for free theories, while counterexample exists for free Dirac fermion in three dimensions. For holographic CFTs described by higher derivative gravity, χ may increase or decrease, depending on the sign of the relevant parameters. Our results may reveal a more profound connection between geometry and distillable entanglement.

  19. Negative regulation and developmental competence in Aspergillus.

    PubMed

    Lee, Mi-Kyung; Kwon, Nak-Jung; Lee, Im-Soon; Jung, Seunho; Kim, Sun-Chang; Yu, Jae-Hyuk

    2016-01-01

    Asexual development (conidiation) in the filamentous fungus Aspergillus nidulans is governed by orchestrated gene expression. The three key negative regulators of conidiation SfgA, VosA, and NsdD act at different control point in the developmental genetic cascade. Here, we have revealed that NsdD is a key repressor affecting the quantity of asexual spores in Aspergillus. Moreover, nullifying both nsdD and vosA results in abundant formation of the development specific structure conidiophores even at 12 h of liquid culture, and near constitutive activation of conidiation, indicating that acquisition of developmental competence involves the removal of negative regulation exerted by both NsdD and VosA. NsdD's role in repressing conidiation is conserved in other aspergilli, as deleting nsdD causes enhanced and precocious activation of conidiation in Aspergillus fumigatus or Aspergillus flavus. In vivo NsdD-DNA interaction analyses identify three NsdD binding regions in the promoter of the essential activator of conidiation brlA, indicating a direct repressive role of NsdD in conidiation. Importantly, loss of flbC or flbD encoding upstream activators of brlA in the absence of nsdD results in delayed activation of brlA, suggesting distinct positive roles of FlbC and FlbD in conidiation. A genetic model depicting regulation of conidiation in A. nidulans is presented. PMID:27364479

  20. Microstructures of negative and positive azeotropes.

    PubMed

    Shephard, J J; Callear, S K; Imberti, S; Evans, J S O; Salzmann, C G

    2016-07-28

    Azeotropes famously impose fundamental restrictions on distillation processes, yet their special thermodynamic properties make them highly desirable for a diverse range of industrial and technological applications. Using neutron diffraction, we investigate the structures of two prototypical azeotropes, the negative acetone-chloroform and the positive benzene-methanol azeotrope. C-HO hydrogen bonding is the dominating interaction in the negative azeotrope but C-ClO halogen bonding contributes as well. Hydrogen-bonded chains of methanol molecules, which are on average longer than in pure methanol, are the defining structural feature of the positive azeotrope illustrating the fundamentally different local mixing in the two kinds of azeotropes. The emerging trend for both azeotropes is that the more volatile components experience the more pronounced structural changes in their local environments as the azeotropes form. The mixing of the acetone-chloroform azeotrope is essentially random above 20 Å, where the running Kirkwood-Buff integrals of our structural model converge closely to the ones expected from thermodynamic data. The benzene-methanol azeotrope on the other hand displays extended methanol-rich regions and consequently the running Kirkwood-Buff integrals oscillate up to at least 60 Å. Our study provides the first experimental insights into the microstructures of azeotropes and a direct link with their thermodynamic properties. Ultimately, this will provide a route for creating tailored molecular environments in azeotropes to improve and fine-tune their performances. PMID:27367534

  1. Demonstration of images with negative group velocities.

    PubMed

    Glasser, Ryan T; Vogl, Ulrich; Lett, Paul D

    2012-06-18

    We report the experimental demonstration of the superluminal propagation of multi-spatial-mode images via four-wave mixing in hot atomic vapor, in which all spatial sub-regions propagate with negative group velocities. We investigate the spatial mode properties and temporal reshaping of the fast light images, and show large relative pulse peak advancements of up to 64 % of the input pulse width. The degree of temporal reshaping is quantified and increases as the relative pulse peak advancement increases. When optimized for image quality or pulse advancement, negative group velocities of up to v(g)=-c/880 and v(g)=-c/2180, respectively, are demonstrated when integrating temporally over the entire image. The present results are applicable to temporal cloaking devices that require strong manipulation of the dispersion relation, where one can envision temporally cloaking various spatial regions of an image for different durations. Additionally, the modes involved in a four-wave mixing process similar to the present experiment have been shown to exhibit quantum correlations and entanglement. The results presented here provide insight into how to tailor experimental tests of the behavior of these quantum correlations and entanglement in the superluminal regime. PMID:22714436

  2. Negative ion extraction from hydrogen plasma bulk

    SciTech Connect

    Oudini, N.; Taccogna, F.; Minelli, P.

    2013-10-15

    A two-dimensional particle-in-cell/Monte Carlo collision model has been developed and used to study low electronegative magnetized hydrogen plasma. A configuration characterized by four electrodes is used: the left electrode is biased at V{sub l} = −100 V, the right electrode is grounded, while the upper and lower transversal electrodes are biased at an intermediate voltage V{sub ud} between 0 and −100 V. A constant and homogeneous magnetic field is applied parallel to the lateral (left/right) electrodes. It is shown that in the magnetized case, the bulk plasma potential is close to the transversal electrodes bias inducing then a reversed sheath in front of the right electrode. The potential drop within the reversed sheath is controlled by the transversal electrodes bias allowing extraction of negative ions with a significant reduction of co-extracted electron current. Furthermore, introducing plasma electrodes, between the transversal electrodes and the right electrode, biased with a voltage just above the plasma bulk potential, increases the negative ion extracted current and decreases significantly the co-extracted electron current. The physical mechanism on basis of this phenomenon has been discussed.

  3. Inflation and Growth: Positive or Negative Relationship?

    NASA Astrophysics Data System (ADS)

    Berument, Hakan; Inamlik, Ali; Olgun, Hasan

    This study has been motivated by two developments. Firstly, by the vast literature on the relationship between inflation and growth which is abundantly endowed with diverse theoretical explanations and contradictory evidence and by the unique experience of the Turkish economy with inflation and growth. A preliminary examination of the Turkish data pointed to a negative relation between inflation and growth. Moreover, there is a unanimous agreement among the students of the Turkish economy that many factors have contributed to inflation in this country. In view of these facts this paper employs a VAR model which will enable us to identify the sources of the shocks and control for external factors. In addition VAR models have a high predictive power and enable the researcher to observe the impulse response functions. The study employs Generalised Impulse Response analysis. In the empirical experiments oil prices, money supply, government spending and taxes have been taken as the most likely determinants of inflation. The study shows that there is a negative relationship between inflation and output growth in Turkey and that the underlying explanatory factor is the real exchange rate. This result is robust.

  4. Bagging and boosting negatively correlated neural networks.

    PubMed

    Islam, Md Monirul; Yao, Xin; Shahriar Nirjon, S M Shahriar; Islam, Muhammad Asiful; Murase, Kazuyuki

    2008-06-01

    In this paper, we propose two cooperative ensemble learning algorithms, i.e., NegBagg and NegBoost, for designing neural network (NN) ensembles. The proposed algorithms incrementally train different individual NNs in an ensemble using the negative correlation learning algorithm. Bagging and boosting algorithms are used in NegBagg and NegBoost, respectively, to create different training sets for different NNs in the ensemble. The idea behind using negative correlation learning in conjunction with the bagging/boosting algorithm is to facilitate interaction and cooperation among NNs during their training. Both NegBagg and NegBoost use a constructive approach to automatically determine the number of hidden neurons for NNs. NegBoost also uses the constructive approach to automatically determine the number of NNs for the ensemble. The two algorithms have been tested on a number of benchmark problems in machine learning and NNs, including Australian credit card assessment, breast cancer, diabetes, glass, heart disease, letter recognition, satellite, soybean, and waveform problems. The experimental results show that NegBagg and NegBoost require a small number of training epochs to produce compact NN ensembles with good generalization. PMID:18558541

  5. Nitric oxide negatively regulates mammalian adult neurogenesis

    NASA Astrophysics Data System (ADS)

    Packer, Michael A.; Stasiv, Yuri; Benraiss, Abdellatif; Chmielnicki, Eva; Grinberg, Alexander; Westphal, Heiner; Goldman, Steven A.; Enikolopov, Grigori

    2003-08-01

    Neural progenitor cells are widespread throughout the adult central nervous system but only give rise to neurons in specific loci. Negative regulators of neurogenesis have therefore been postulated, but none have yet been identified as subserving a significant role in the adult brain. Here we report that nitric oxide (NO) acts as an important negative regulator of cell proliferation in the adult mammalian brain. We used two independent approaches to examine the function of NO in adult neurogenesis. In a pharmacological approach, we suppressed NO production in the rat brain by intraventricular infusion of an NO synthase inhibitor. In a genetic approach, we generated a null mutant neuronal NO synthase knockout mouse line by targeting the exon encoding active center of the enzyme. In both models, the number of new cells generated in neurogenic areas of the adult brain, the olfactory subependyma and the dentate gyrus, was strongly augmented, which indicates that division of neural stem cells in the adult brain is controlled by NO and suggests a strategy for enhancing neurogenesis in the adult central nervous system.

  6. How quantum are non-negative wavefunctions?

    NASA Astrophysics Data System (ADS)

    Hastings, M. B.

    2016-01-01

    We consider wavefunctions which are non-negative in some tensor product basis. We study what possible teleportation can occur in such wavefunctions, giving a complete answer in some cases (when one system is a qubit) and partial answers elsewhere. We use this to show that a one-dimensional wavefunction which is non-negative and has zero correlation length can be written in a "coherent Gibbs state" form, as explained later. We conjecture that such holds in higher dimensions. Additionally, some results are provided on possible teleportation in general wavefunctions, explaining how Schmidt coefficients before measurement limit the possible Schmidt coefficients after measurement, and on the absence of a "generalized area law" [D. Aharonov et al., in Proceedings of Foundations of Computer Science (FOCS) (IEEE, 2014), p. 246; e-print arXiv.org:1410.0951] even for Hamiltonians with no sign problem. One of the motivations for this work is an attempt to prove a conjecture about ground state wavefunctions which have an "intrinsic" sign problem that cannot be removed by any quantum circuit. We show a weaker version of this, showing that the sign problem is intrinsic for commuting Hamiltonians in the same phase as the double semion model under the technical assumption that TQO-2 holds [S. Bravyi et al., J. Math. Phys. 51, 093512 (2010)].

  7. Underpowered samples, false negatives, and unconscious learning.

    PubMed

    Vadillo, Miguel A; Konstantinidis, Emmanouil; Shanks, David R

    2016-02-01

    The scientific community has witnessed growing concern about the high rate of false positives and unreliable results within the psychological literature, but the harmful impact of false negatives has been largely ignored. False negatives are particularly concerning in research areas where demonstrating the absence of an effect is crucial, such as studies of unconscious or implicit processing. Research on implicit processes seeks evidence of above-chance performance on some implicit behavioral measure at the same time as chance-level performance (that is, a null result) on an explicit measure of awareness. A systematic review of 73 studies of contextual cuing, a popular implicit learning paradigm, involving 181 statistical analyses of awareness tests, reveals how underpowered studies can lead to failure to reject a false null hypothesis. Among the studies that reported sufficient information, the meta-analytic effect size across awareness tests was d z = 0.31 (95 % CI 0.24-0.37), showing that participants' learning in these experiments was conscious. The unusually large number of positive results in this literature cannot be explained by selective publication. Instead, our analyses demonstrate that these tests are typically insensitive and underpowered to detect medium to small, but true, effects in awareness tests. These findings challenge a widespread and theoretically important claim about the extent of unconscious human cognition. PMID:26122896

  8. Development of versatile multiaperture negative ion sources

    SciTech Connect

    Cavenago, M.; Minarello, A.; Sattin, M.; Serianni, G.; Antoni, V.; Bigi, M.; Pasqualotto, R.; Recchia, M.; Veltri, P.; Agostinetti, P.; Barbisan, M.; Baseggio, L.; Cervaro, V.; Degli Agostini, F.; Franchin, L.; Laterza, B.; Ravarotto, D.; Rossetto, F.; Zaniol, B.; Zucchetti, S.; and others

    2015-04-08

    Enhancement of negative ion sources for production of large ion beams is a very active research field nowadays, driven from demand of plasma heating in nuclear fusion devices and accelerator applications. As a versatile test bench, the ion source NIO1 (Negative Ion Optimization 1) is being commissioned by Consorzio RFX and INFN. The nominal beam current of 135 mA at −60 kV is divided into 9 beamlets, with multiaperture extraction electrodes. The plasma is sustained by a 2 MHz radiofrequency power supply, with a standard matching box. A High Voltage Deck (HVD) placed inside the lead shielding surrounding NIO1 contains the radiofrequency generator, the gas control, electronics and power supplies for the ion source. An autonomous closed circuit water cooling system was installed for the whole system, with a branch towards the HVD, using carefully optimized helical tubing. Insulation transformer is installed in a nearby box. Tests of several magnetic configurations can be performed. Status of experiments, measured spectra and plasma luminosity are described. Upgrades of magnetic filter, beam calorimeter and extraction grid and related theoretical issues are reviewed.

  9. Negative Ions for Emerging Interdisciplinary Applications

    SciTech Connect

    Guharay, Samar K.

    2011-09-26

    In many applications related to ion beam-materials interactions negative ions are particularly desirable due to its merit to yield a very low surface charge-up voltage, {approx} a few volts, for both electrically isolated surfaces and insulators. Some important applications pertaining to ion beam-material interactions include surface analysis by secondary ion mass spectrometry (SIMS), voltage-contrast microscopy for semiconductor device inspection, materials processing, and ion beam lithography. These applications primarily require vacuum environments. On the other hand, a distinct area of activities constitutes formation of ions and ion transport in ambient environmental conditions, i.e., at atmospheric pressures. In this context, ion mobility spectrometry (IMS) is an important analytical device that uses negative ions and operates at ambient conditions. IMS is widely used in both physical and biological sciences including monitoring environmental conditions, security screening and disease detection. This article highlights several critical issues related to the ionization sources and ion transport in IMS. Additionally, the critical issues related to ion sources, transport and focusing are discussed in the context of SIMS with sub-micrometer spatial resolution.

  10. Emotion and hypervigilance: negative affect predicts increased P1 responses to non-negative pictorial stimuli.

    PubMed

    Schomberg, Jessica; Schöne, Benjamin; Gruber, Thomas; Quirin, Markus

    2016-06-01

    Previous research has demonstrated that negative affect influences attentional processes. Here, we investigate whether pre-experimental negative affect predicts a hypervigilant neural response as indicated by increased event-related potential amplitudes in response to neutral and positive visual stimuli. In our study, seventeen male participants filled out the German version of the positive and negative affect schedule (Watson et al. in J Pers Soc Psychol 54:1063-1070, 1988; Krohne et al. in Diagnostica 42:139-156, 1996) and subsequently watched positive (erotica, extreme sports, beautiful women) and neutral (daily activities) photographs while electroencephalogram was recorded. In line with our hypothesis, low state negative affect but not (reduced) positive affect predicted an increase in the first positive event-related potential amplitude P1 as a typical marker of increased selective attention. As this effect occurred in response to non-threatening picture conditions, negative affect may foster an individual's general hypervigilance, a state that has formerly been associated with psychopathology only. PMID:26749180

  11. Integrating Negative Affect Measures in a Measurement Model: Assessing the Function of Negative Affect as Interference to Self-Regulation

    ERIC Educational Resources Information Center

    Magno, Carlo

    2010-01-01

    The present study investigated the composition of negative affect and its function as inhibitory to thought processes such as self-regulation. Negative affect in the present study were composed of anxiety, worry, thought suppression, and fear of negative evaluation. These four factors were selected based on the criteria of negative affect by…

  12. Community Detection in Signed Networks: the Role of Negative ties in Different Scales

    NASA Astrophysics Data System (ADS)

    Esmailian, Pouya; Jalili, Mahdi

    2015-09-01

    Extracting community structure of complex network systems has many applications from engineering to biology and social sciences. There exist many algorithms to discover community structure of networks. However, it has been significantly under-explored for networks with positive and negative links as compared to unsigned ones. Trying to fill this gap, we measured the quality of partitions by introducing a Map Equation for signed networks. It is based on the assumption that negative relations weaken positive flow from a node towards a community, and thus, external (internal) negative ties increase the probability of staying inside (escaping from) a community. We further extended the Constant Potts Model, providing a map spectrum for signed networks. Accordingly, a partition is selected through balancing between abridgment and expatiation of a signed network. Most importantly, multi-scale spectrum of signed networks revealed how informative are negative ties in different scales, and quantified the topological placement of negative ties between dense positive ones. Moreover, an inconsistency was found in the signed Modularity: as the number of negative ties increases, the density of positive ties is neglected more. These results shed lights on the community structure of signed networks.

  13. Community Detection in Signed Networks: the Role of Negative ties in Different Scales

    PubMed Central

    Esmailian, Pouya; Jalili, Mahdi

    2015-01-01

    Extracting community structure of complex network systems has many applications from engineering to biology and social sciences. There exist many algorithms to discover community structure of networks. However, it has been significantly under-explored for networks with positive and negative links as compared to unsigned ones. Trying to fill this gap, we measured the quality of partitions by introducing a Map Equation for signed networks. It is based on the assumption that negative relations weaken positive flow from a node towards a community, and thus, external (internal) negative ties increase the probability of staying inside (escaping from) a community. We further extended the Constant Potts Model, providing a map spectrum for signed networks. Accordingly, a partition is selected through balancing between abridgment and expatiation of a signed network. Most importantly, multi-scale spectrum of signed networks revealed how informative are negative ties in different scales, and quantified the topological placement of negative ties between dense positive ones. Moreover, an inconsistency was found in the signed Modularity: as the number of negative ties increases, the density of positive ties is neglected more. These results shed lights on the community structure of signed networks. PMID:26395815

  14. Worse Health Status and Higher Incidence of Health Disorders in Rhesus Negative Subjects

    PubMed Central

    Flegr, Jaroslav; Hoffmann, Rudolf; Dammann, Mike

    2015-01-01

    Rhesus-positive and Rhesus-negative persons differ in the presence-absence of highly immunogenic RhD protein on the erythrocyte membrane. The biological function of the RhD molecule is unknown. Its structure suggests that the molecular complex with RhD protein transports NH3 or CO2 molecules across the erythrocyte cell membrane. Some data indicate that RhD positive and RhD negative subjects differ in their tolerance to certain biological factors, including, Toxoplasma infection, aging and fatique. Present cross sectional study performed on 3,130 subjects) showed that Rhesus negative subjects differed in many indices of their health status, including incidences of many disorders. Rhesus negative subjects reported to have more frequent allergic, digestive, heart, hematological, immunity, mental health, and neurological problems. On the population level, a Rhesus-negativity-associated burden could be compensated for, for example, by the heterozygote advantage, but for Rhesus negative subjects this burden represents a serious problem. PMID:26495842

  15. Community Detection in Signed Networks: the Role of Negative ties in Different Scales.

    PubMed

    Esmailian, Pouya; Jalili, Mahdi

    2015-01-01

    Extracting community structure of complex network systems has many applications from engineering to biology and social sciences. There exist many algorithms to discover community structure of networks. However, it has been significantly under-explored for networks with positive and negative links as compared to unsigned ones. Trying to fill this gap, we measured the quality of partitions by introducing a Map Equation for signed networks. It is based on the assumption that negative relations weaken positive flow from a node towards a community, and thus, external (internal) negative ties increase the probability of staying inside (escaping from) a community. We further extended the Constant Potts Model, providing a map spectrum for signed networks. Accordingly, a partition is selected through balancing between abridgment and expatiation of a signed network. Most importantly, multi-scale spectrum of signed networks revealed how informative are negative ties in different scales, and quantified the topological placement of negative ties between dense positive ones. Moreover, an inconsistency was found in the signed Modularity: as the number of negative ties increases, the density of positive ties is neglected more. These results shed lights on the community structure of signed networks. PMID:26395815

  16. Food-web complexity, meta-community complexity and community stability.

    PubMed

    Mougi, A; Kondoh, M

    2016-01-01

    What allows interacting, diverse species to coexist in nature has been a central question in ecology, ever since the theoretical prediction that a complex community should be inherently unstable. Although the role of spatiality in species coexistence has been recognized, its application to more complex systems has been less explored. Here, using a meta-community model of food web, we show that meta-community complexity, measured by the number of local food webs and their connectedness, elicits a self-regulating, negative-feedback mechanism and thus stabilizes food-web dynamics. Moreover, the presence of meta-community complexity can give rise to a positive food-web complexity-stability effect. Spatiality may play a more important role in stabilizing dynamics of complex, real food webs than expected from ecological theory based on the models of simpler food webs. PMID:27071716

  17. Food-web complexity, meta-community complexity and community stability

    PubMed Central

    Mougi, A.; Kondoh, M.

    2016-01-01

    What allows interacting, diverse species to coexist in nature has been a central question in ecology, ever since the theoretical prediction that a complex community should be inherently unstable. Although the role of spatiality in species coexistence has been recognized, its application to more complex systems has been less explored. Here, using a meta-community model of food web, we show that meta-community complexity, measured by the number of local food webs and their connectedness, elicits a self-regulating, negative-feedback mechanism and thus stabilizes food-web dynamics. Moreover, the presence of meta-community complexity can give rise to a positive food-web complexity-stability effect. Spatiality may play a more important role in stabilizing dynamics of complex, real food webs than expected from ecological theory based on the models of simpler food webs. PMID:27071716

  18. Negative grouting consequences on karst environment

    NASA Astrophysics Data System (ADS)

    Bonacci, O.; Roje-Bonacci, T.; Gottstein, S.

    2009-04-01

    Grouting is a procedure by means of which grout is injected into different kinds of karst spaces (cracks, fissures, conduits and caves). It has a wide application in modern civil engineering, especially in karst terrains. It started nearly 200 years ago. In most cases the ingredients for the preparation of mortars and grouting suspensions are: cement, bentonite, clay and fillers, additives for stability and water. In practice the composition of grouting suspension is not standardized. A suspension injected under pressure will circulate in the karst spaces like a more or less viscous fluid until some of the larger suspended particles are blocked where the karst voids get narrower than the size of injected grains. The injection of materials into karst groundwater, i.e. the construction of grouting curtains, definitely could be the cause of unpredictable negative consequences on karst groundwater environments. The building of dams in karst areas always go along the construction of grouting curtains. During the construction of most dams in karst all over the world millions tons of injection mass have been injected in karst underground. It may impact water quantity in vadose zone and in karstic aquifer causing water table lowering and spring desiccation. In such cases the negative impact on local karst environment could be very dangerous. Physically as well as chemically this mass voraciously and quickly destroyed underground habitats and killed an enormous number of endangered and endemic species. Very often this is extremely expensive procedure and in many cases not very successful from the engineering point of view. From the ecological point of view it could causes catastrophic consequences. The greatest problem is that until now neither engineers nor ecologists took care of these great and massive negative influences on underground karst environments. In this paper few examples of different consequences of grouting on the hydrogeological as well as ecological regime

  19. Negative hydrogen ion yields at plasma grid surface in a negative hydrogen ion source

    SciTech Connect

    Wada, M.; Kenmotsu, T.; Sasao, M.

    2015-04-08

    Negative hydrogen (H{sup −}) ion yield from the plasma grid due to incident hydrogen ions and neutrals has been evaluated with the surface collision cascade model, ACAT (Atomic Collision in Amorphous Target) coupled to a negative surface ionization models. Dependence of negative ion fractions upon the velocity component normal to the surface largely affect the calculation results of the final energy and angular distributions of the H{sup −} ions. The influence is particularly large for H{sup −} ions desorbed from the surface due to less than several eV hydrogen particle implact. The present calculation predicts that H{sup −} ion yield can be maximized by setting the incident angle of hydrogen ions and neutrals to be 65 degree. The Cs thickness on the plasma grid should also affect the yields and mean energies of surface produced H{sup −} ions by back scattering and ion induced desorption processes.

  20. A Study of Neoadjuvant Paclitaxel in Combination With Bavituximab in Early- Stage Triple- Negative Breast Cancer

    ClinicalTrials.gov

    2016-02-12

    Breast Cancer; Triple Negative Breast Neoplasms; Triple-Negative Breast Neoplasm; Triple-Negative Breast Cancer; Triple Negative Breast Cancer; ER-Negative PR-Negative HER2-Negative Breast Neoplasms; ER-Negative PR-Negative HER2-Negative Breast Cancer