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Sample records for suppresses capsaicin-evoked behavioral

  1. Effect of sympathetic activity on capsaicin-evoked pain, hyperalgesia, and vasodilatation.

    Science.gov (United States)

    Baron, R; Wasner, G; Borgstedt, R; Hastedt, E; Schulte, H; Binder, A; Kopper, F; Rowbotham, M; Levine, J D; Fields, H L

    1999-03-23

    Painful nerve and tissue injuries can be exacerbated by activity in sympathetic neurons. The mechanisms of sympathetically maintained pain (SMP) are unclear. To determine the effect of cutaneous sympathetic activity on pain induced by primary afferent C-nociceptor sensitization with capsaicin in humans. In healthy volunteers capsaicin was applied topically (n = 12) or injected into the forearm skin (n = 10) to induce spontaneous pain, dynamic and punctate mechanical hyperalgesia, and antidromic (axon reflex) vasodilatation (flare). Intensity of pain and hyperalgesia, axon reflex vasodilatation (laser Doppler), and flare size and area of hyperalgesia (planimetry) were assessed. The local skin temperature at the application and measurement sites was kept constant at 35 degrees C. In each individual the analyses were performed during the presence of high and low sympathetic skin activity induced by whole-body cooling and warming with a thermal suit. By this method sympathetic vasoconstrictor activity is modulated in the widest range that can be achieved physiologically. The degree of vasoconstrictor discharge was monitored by measuring skin blood flow (laser Doppler) and temperature (infrared thermometry) at the index finger. The intensity and spatial distribution of capsaicin-evoked spontaneous pain and dynamic and punctate mechanical hyperalgesia were identical during the presence of high and low sympathetic discharge. Antidromic vasodilatation and flare size were significantly diminished when sympathetic vasoconstrictor neurons were excited. Cutaneous sympathetic vasoconstrictor activity does not influence spontaneous pain and mechanical hyperalgesia after capsaicin-induced C-nociceptor sensitization. When using physiologic stimulation of sympathetic activity, the capsaicin model is not useful for elucidating mechanisms of SMP. In neuropathic pain states with SMP, different mechanisms may be present.

  2. Differential effect of intravenous S-ketamine and fentanyl on atypical odontalgia and capsaicin-evoked pain

    DEFF Research Database (Denmark)

    Baad-Hansen, Lene; Juhl, Gitte Irene; Jensen, Troels Staehelin

    2007-01-01

    temporal summation were compared between groups and sides. Both drugs failed to produce an analgesic effect on spontaneous AO pain, but fentanyl effectively reduced capsaicin-evoked pain. AO patients showed increased sensitivity to capsaicin and heat pain, but no significant differences in cold......Atypical odontalgia (AO) is an intraoral pain condition of currently unknown mechanisms. In 10 AO patients and 10 matched healthy controls, we examined the effect of intravenous infusion of an N-methyl-D-aspartate (NMDA) receptor antagonist S-ketamine and a mu-opioid agonist fentanyl on spontaneous...... AO pain and on an acute intraoral nociceptive input evoked by topical application of capsaicin. The drugs were administered in a randomized, placebo-controlled, cross-over manner. Furthermore, measures of intraoral sensitivity to mechanical and thermal quantitative sensory testing (QST) including...

  3. A mixed integer program to model spatial wildfire behavior and suppression placement decisions

    Science.gov (United States)

    Erin J. Belval; Yu Wei; Michael. Bevers

    2015-01-01

    Wildfire suppression combines multiple objectives and dynamic fire behavior to form a complex problem for decision makers. This paper presents a mixed integer program designed to explore integrating spatial fire behavior and suppression placement decisions into a mathematical programming framework. Fire behavior and suppression placement decisions are modeled using...

  4. Cold suppresses agonist-induced activation of TRPV1.

    Science.gov (United States)

    Chung, M-K; Wang, S

    2011-09-01

    Cold therapy is frequently used to reduce pain and edema following acute injury or surgery such as tooth extraction. However, the neurobiological mechanisms of cold therapy are not completely understood. Transient receptor potential vanilloid 1 (TRPV1) is a capsaicin- and heat-gated nociceptive ion channel implicated in thermosensation and pathological pain under conditions of inflammation or injury. Although capsaicin-induced nociception, neuropeptide release, and ionic currents are suppressed by cold, it is not known if cold suppresses agonist-induced activation of recombinant TRPV1. We demonstrate that cold strongly suppressed the activation of recombinant TRPV1 by multiple agonists and capsaicin-evoked currents in trigeminal ganglia neurons under normal and phosphorylated conditions. Cold-induced suppression was partially impaired in a TRPV1 mutant that lacked heat-mediated activation and potentiation. These results suggest that cold-induced suppression of TRPV1 may share a common molecular basis with heat-induced potentiation, and that allosteric inhibition may contribute, in part, to the cold-induced suppression. We also show that combination of cold and a specific antagonist of TRPV1 can produce an additive suppression. Our results provide a mechanistic basis for cold therapy and may enhance anti-nociceptive approaches that target TRPV1 for managing pain under inflammation and tissue injury, including that from tooth extraction.

  5. Behavioral and EEG evidence for auditory memory suppression

    Directory of Open Access Journals (Sweden)

    Maya Elizabeth Cano

    2016-03-01

    Full Text Available The neural basis of motivated forgetting using the Think/No-Think (TNT paradigm is receiving increased attention with a particular focus on the mechanisms that enable memory suppression. However, most TNT studies have been limited to the visual domain. To assess whether and to what extent direct memory suppression extends across sensory modalities, we examined behavioral and electroencephalographic (EEG effects of auditory Think/No-Think in healthy young adults by adapting the TNT paradigm to the auditory modality. Behaviorally, suppression of memory strength was indexed by prolonged response times during the retrieval of subsequently remembered No-Think words. We examined task-related EEG activity of both attempted memory retrieval and inhibition of a previously learned target word during the presentation of its paired associate. Event-related EEG responses revealed two main findings: 1 a centralized Think > No-Think positivity during auditory word presentation (from approximately 0-500ms, and 2 a sustained Think positivity over parietal electrodes beginning at approximately 600ms reflecting the memory retrieval effect which was significantly reduced for No-Think words. In addition, word-locked theta (4-8 Hz power was initially greater for No-Think compared to Think during auditory word presentation over fronto-central electrodes. This was followed by a posterior theta increase indexing successful memory retrieval in the Think condition.The observed event-related potential pattern and theta power analysis are similar to that reported in visual Think/No-Think studies and support a modality non-specific mechanism for memory inhibition. The EEG data also provide evidence supporting differing roles and time courses of frontal and parietal regions in the flexible control of auditory memory.

  6. Behavioral and EEG Evidence for Auditory Memory Suppression.

    Science.gov (United States)

    Cano, Maya E; Knight, Robert T

    2016-01-01

    The neural basis of motivated forgetting using the Think/No-Think (TNT) paradigm is receiving increased attention with a particular focus on the mechanisms that enable memory suppression. However, most TNT studies have been limited to the visual domain. To assess whether and to what extent direct memory suppression extends across sensory modalities, we examined behavioral and electroencephalographic (EEG) effects of auditory TNT in healthy young adults by adapting the TNT paradigm to the auditory modality. Behaviorally, suppression of memory strength was indexed by prolonged response time (RTs) during the retrieval of subsequently remembered No-Think words. We examined task-related EEG activity of both attempted memory retrieval and inhibition of a previously learned target word during the presentation of its paired associate. Event-related EEG responses revealed two main findings: (1) a centralized Think > No-Think positivity during auditory word presentation (from approximately 0-500 ms); and (2) a sustained Think positivity over parietal electrodes beginning at approximately 600 ms reflecting the memory retrieval effect which was significantly reduced for No-Think words. In addition, word-locked theta (4-8 Hz) power was initially greater for No-Think compared to Think during auditory word presentation over fronto-central electrodes. This was followed by a posterior theta increase indexing successful memory retrieval in the Think condition. The observed event-related potential pattern and theta power analysis are similar to that reported in visual TNT studies and support a modality non-specific mechanism for memory inhibition. The EEG data also provide evidence supporting differing roles and time courses of frontal and parietal regions in the flexible control of auditory memory.

  7. Emotion suppression, emotional eating, and eating behavior among parent-adolescent dyads.

    Science.gov (United States)

    Ferrer, Rebecca A; Green, Paige A; Oh, April Y; Hennessy, Erin; Dwyer, Laura A

    2017-10-01

    Emotion suppression may lead to ironic increases in emotional experience. More important, suppression is a transactional process, creating stress and disrupting interactions for the suppressor and those in social interactions with individuals who are suppressing emotion. However, no research has examined the behavioral consequences of emotion suppression in close relationships. We examine the possibility that emotion suppression will predict eating behaviors as a secondary emotion regulatory strategy among 1,556 parent-adolescent dyads (N = 3,112), consistent with evidence suggesting that suppression influences eating at the individual-level. Actor-partner interdependence models and structural equation modeling demonstrate that one's own emotion suppression was associated with emotional eating; greater consumption of hedonic-low nutrient, high energy dense-foods; and lower consumption of fruits and vegetables (actor effects). One's partner's emotion suppression was also independently associated with one's own emotional eating; lower consumption of fruits and vegetables; and greater consumption of hedonic foods (partner effects), although this association was most consistent for adolescents' suppression and parents' eating (compared with the converse). These analyses suggest that dyadic emotion regulatory processes have implications on eating behavior. Moreover, analyses suggest that emotion suppression has potential implications on eating behaviors of others within close relationships with a suppressor, consistent with the notion that emotion regulation is a transactional process. These findings suggest that interventions to improve eating habits of parents and their adolescent children should consider dyadic emotion regulatory processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. Combined Electrophysiological and Behavioral Evidence for the Suppression of Salient Distractors.

    Science.gov (United States)

    Gaspelin, Nicholas; Luck, Steven J

    2018-05-15

    Researchers have long debated how salient-but-irrelevant features guide visual attention. Pure stimulus-driven theories claim that salient stimuli automatically capture attention irrespective of goals, whereas pure goal-driven theories propose that an individual's attentional control settings determine whether salient stimuli capture attention. However, recent studies have suggested a hybrid model in which salient stimuli attract visual attention but can be actively suppressed by top-down attentional mechanisms. Support for this hybrid model has primarily come from ERP studies demonstrating that salient stimuli, which fail to capture attention, also elicit a distractor positivity (P D ) component, a putative neural index of suppression. Other support comes from a handful of behavioral studies showing that processing at the salient locations is inhibited compared with other locations. The current study was designed to link the behavioral and neural evidence by combining ERP recordings with an experimental paradigm that provides a behavioral measure of suppression. We found that, when a salient distractor item elicited the P D component, processing at the location of this distractor was suppressed below baseline levels. Furthermore, the magnitude of behavioral suppression and the magnitude of the P D component covaried across participants. These findings provide a crucial connection between the behavioral and neural measures of suppression, which opens the door to using the P D component to assess the timing and neural substrates of the behaviorally observed suppression.

  9. Movement Suppression Time-Out for Undesirable Behavior in Psychotic and Severely Developmentally Delayed Children.

    Science.gov (United States)

    Rolider, Ahmos; Van Houten, Ron

    1985-01-01

    Effects of a movement suppression time-out, which involved punishing any movements or verbalization while a client is in the time-out area, were evaluated in four experiments. The procedure produced a larger reduction in the target behavior in all three children and effectiveness was explained in terms of suppression of self-stimulation during…

  10. Amphetamine and cocaine suppress social play behavior in rats through distinct mechanisms.

    Science.gov (United States)

    Achterberg, E J Marijke; Trezza, Viviana; Siviy, Stephen M; Schrama, Laurens; Schoffelmeer, Anton N M; Vanderschuren, Louk J M J

    2014-04-01

    Social play behavior is a characteristic form of social behavior displayed by juvenile and adolescent mammals. This social play behavior is highly rewarding and of major importance for social and cognitive development. Social play is known to be modulated by neurotransmitter systems involved in reward and motivation. Interestingly, psychostimulant drugs, such as amphetamine and cocaine, profoundly suppress social play, but the neural mechanisms underlying these effects remain to be elucidated. In this study, we investigated the pharmacological underpinnings of amphetamine- and cocaine-induced suppression of social play behavior in rats. The play-suppressant effects of amphetamine were antagonized by the alpha-2 adrenoreceptor antagonist RX821002 but not by the dopamine receptor antagonist alpha-flupenthixol. Remarkably, the effects of cocaine on social play were not antagonized by alpha-2 noradrenergic, dopaminergic, or serotonergic receptor antagonists, administered either alone or in combination. The effects of a subeffective dose of cocaine were enhanced by a combination of subeffective doses of the serotonin reuptake inhibitor fluoxetine, the dopamine reuptake inhibitor GBR12909, and the noradrenaline reuptake inhibitor atomoxetine. Amphetamine, like methylphenidate, exerts its play-suppressant effect through alpha-2 noradrenergic receptors. On the other hand, cocaine reduces social play by simultaneous increases in dopamine, noradrenaline, and serotonin neurotransmission. In conclusion, psychostimulant drugs with different pharmacological profiles suppress social play behavior through distinct mechanisms. These data contribute to our understanding of the neural mechanisms of social behavior during an important developmental period, and of the deleterious effects of psychostimulant exposure thereon.

  11. Behavioral Immunity Suppresses an Epizootic in Caribbean Spiny Lobsters.

    Science.gov (United States)

    Butler, Mark J; Behringer, Donald C; Dolan, Thomas W; Moss, Jessica; Shields, Jeffrey D

    2015-01-01

    Sociality has evolved in a wide range of animal taxa but infectious diseases spread rapidly in populations of aggregated individuals, potentially negating the advantages of their social interactions. To disengage from the coevolutionary struggle with pathogens, some hosts have evolved various forms of "behavioral immunity"; yet, the effectiveness of such behaviors in controlling epizootics in the wild is untested. Here we show how one form of behavioral immunity (i.e., the aversion of diseased conspecifics) practiced by Caribbean spiny lobsters (Panulirus argus) when subject to the socially transmitted PaV1 virus, appears to have prevented an epizootic over a large seascape. We capitalized on a "natural experiment" in which a die-off of sponges in the Florida Keys (USA) resulted in a loss of shelters for juvenile lobsters over a ~2500km2 region. Lobsters were thus concentrated in the few remaining shelters, presumably increasing their exposure to the contagious virus. Despite this spatial reorganization of the population, viral prevalence in lobsters remained unchanged after the sponge die-off and for years thereafter. A field experiment in which we introduced either a healthy or PaV1-infected lobster into lobster aggregations in natural dens confirmed that spiny lobsters practice behavioral immunity. Healthy lobsters vacated dens occupied by PaV1-infected lobsters despite the scarcity of alternative shelters and the higher risk of predation they faced when searching for a new den. Simulations from a spatially-explicit, individual-based model confirmed our empirical results, demonstrating the efficacy of behavioral immunity in preventing epizootics in this system.

  12. Behavioral Immunity Suppresses an Epizootic in Caribbean Spiny Lobsters.

    Directory of Open Access Journals (Sweden)

    Mark J Butler

    Full Text Available Sociality has evolved in a wide range of animal taxa but infectious diseases spread rapidly in populations of aggregated individuals, potentially negating the advantages of their social interactions. To disengage from the coevolutionary struggle with pathogens, some hosts have evolved various forms of "behavioral immunity"; yet, the effectiveness of such behaviors in controlling epizootics in the wild is untested. Here we show how one form of behavioral immunity (i.e., the aversion of diseased conspecifics practiced by Caribbean spiny lobsters (Panulirus argus when subject to the socially transmitted PaV1 virus, appears to have prevented an epizootic over a large seascape. We capitalized on a "natural experiment" in which a die-off of sponges in the Florida Keys (USA resulted in a loss of shelters for juvenile lobsters over a ~2500km2 region. Lobsters were thus concentrated in the few remaining shelters, presumably increasing their exposure to the contagious virus. Despite this spatial reorganization of the population, viral prevalence in lobsters remained unchanged after the sponge die-off and for years thereafter. A field experiment in which we introduced either a healthy or PaV1-infected lobster into lobster aggregations in natural dens confirmed that spiny lobsters practice behavioral immunity. Healthy lobsters vacated dens occupied by PaV1-infected lobsters despite the scarcity of alternative shelters and the higher risk of predation they faced when searching for a new den. Simulations from a spatially-explicit, individual-based model confirmed our empirical results, demonstrating the efficacy of behavioral immunity in preventing epizootics in this system.

  13. Weight Suppression in Bulimia Nervosa: Associations with Biology and Behavior

    Science.gov (United States)

    Bodell, Lindsay P.; Keel, Pamela K.

    2015-01-01

    Bulimia nervosa (BN) is a serious eating disorder that can persist for years and contribute to medical complications and increased mortality, underscoring the need to better understand factors maintaining this disorder. Higher levels of weight suppression (WS) have been found to predict both the onset and maintenance of BN; however, no studies have examined mechanisms that may account for the effects of WS on BN. We hypothesized that high WS would lead to reduced leptin levels, which may increase risk of binge eating by modulating reward responses to food. The current study examined the relationship between WS, leptin levels, and the reinforcing value of food in women with BN (n=32) and non-eating disorder controls (n=30). Participants provided information on WS, completed a fasting blood draw to obtain serum leptin, and completed a progressive ratio task to measure the reinforcing value of food. Individuals with BN had greater WS (p<.01) and reinforcing food value (p<.05) compared to controls. Additionally, higher WS was associated with both lower leptin (p<.05) and increased reinforcing value of food (p<.05). Contrary to hypotheses, BN and control participants did not differ significantly on leptin levels, and leptin levels were not significantly associated with the reinforcing value of food. Findings support that efforts to conform to the thin ideal may alter drive to consume rewarding foods and leave women vulnerable to binge episodes. However, mechanisms through which WS contributes to food reward and binge eating remain unknown. PMID:26191637

  14. Rapid and Persistent Suppression of Feeding Behavior Induced by Sensitization Training in "Aplysia"

    Science.gov (United States)

    Acheampong, Ama; Kelly, Kathleen; Shields-Johnson, Maria; Hajovsky, Julie; Wainwright, Marcy; Mozzachiodi, Riccardo

    2012-01-01

    In "Aplysia," noxious stimuli induce sensitization of defensive responses. However, it remains largely unknown whether such stimuli also alter nondefensive behaviors. In this study, we examined the effects of noxious stimuli on feeding. Strong electric shocks, capable of inducing sensitization, also led to the suppression of feeding. The use of…

  15. Acupuncture suppresses reinstatement of morphine-seeking behavior induced by a complex cue in rats.

    Science.gov (United States)

    Lee, Bong Hyo; Lim, Sung Chul; Jeon, Hyeon Jeong; Kim, Jae Su; Lee, Yun Kyu; Lee, Hyun Jong; In, Sunghyun; Kim, Hee Young; Yoon, Seong Shoon; Yang, Chae Ha

    2013-08-26

    Morphine causes physical and psychological dependence for individuals after repeated-use. Above all, our previous study showed that acupuncture attenuated reinstatement of morphine-seeking behavior induced by pharmacological cue. In this study, we investigated whether acupuncture could suppress the reinstatement of morphine-seeking behavior induced by the combination of environmental and pharmacological cues and the possible neuronal involvement. Male Sprague-Dawley rats were trained to self-administer morphine (1.0 mg/kg) for 3 weeks. Following the withdrawal phase (7 days), the effects of acupuncture on reinstatement of morphine-seeking behavior were investigated. For the investigation of neuronal involvement, the GABAA receptor antagonist bicuculline and the GABAB receptor antagonist SCH 50911 were pre-treated. Morphine-seeking behavior induced by combination of re-exposure to the operant chamber and morphine injection was suppressed perfectly by acupuncture at SI5, but not at the control acupoint LI5 and this effect was blocked by pre-treatment with the GABA receptor antagonists. This study suggests that acupuncture at SI5 can be considered as a predominant therapy for the reinstatement of morphine-seeking behavior in humans. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  16. Peripheral and central mediators of lipopolysaccharide induced suppression of defensive rage behavior in the cat.

    Science.gov (United States)

    Bhatt, S; Bhatt, R S; Zalcman, S S; Siegel, A

    2009-11-10

    Based upon recent findings in our laboratory that cytokines microinjected into the medial hypothalamus or periaqueductal gray (PAG) powerfully modulate defensive rage behavior in cat, the present study determined the effects of peripherally released cytokines following lipopolysaccharide (LPS) challenge upon defensive rage. The study involved initial identification of the effects of peripheral administration of LPS upon defensive rage by electrical stimulation from PAG and subsequent determination of the peripheral and central mechanisms governing this process. The results revealed significant elevation in response latencies for defensive rage from 60 to 300 min, post LPS injection, with no detectable signs of sickness behavior present at 60 min. In contrast, head turning behavior elicited by stimulation of adjoining midbrain sites was not affected by LPS administration, suggesting a specificity of the effects of LPS upon defensive rage. Direct administration of LPS into the medial hypothalamus had no effect on defensive rage, suggesting that the effects of LPS were mediated by peripheral cytokines rather than by any direct actions upon hypothalamic neurons. Complete blockade of the suppressive effects of LPS by peripheral pretreatment with an Anti-tumor necrosis factor-alpha (TNFalpha) antibody but not with an anti- interleukin-1 (IL-1) antibody demonstrated that the effects of LPS were mediated through TNF-alpha rather than through an IL-1 mechanism. A determination of the central mechanisms governing LPS suppression revealed that pretreatment of the medial hypothalamus with PGE(2) or 5-HT(1A) receptor antagonists each completely blocked the suppressive effects of LPS, while microinjections of a TNF-alpha antibody into the medial hypothalamus were ineffective. Microinjections of -Iodo-N-[2-[4-(methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl) benzamide monohydrochloride (p-MPPI) into lateral hypothalamus (to test for anatomical specificity) had no effect upon

  17. Experimental investigation on the behavior of pressure suppression containment systems by the SOPRE-1 facility

    International Nuclear Information System (INIS)

    Cerullo, N.; Delli Gatti, A.; Marinelli, M.; Mazzini, M.; Mazzoni, A.; Sbrana, A.; Todisco, P.

    1977-01-01

    The SOPRE-1 test facility is an integral model (scale 1:13) of a MARK II pressure suppression containment system. It was set up at the University of Pisa in order to study the pressure-temperature transient in pressure suppression containment systems during LOCAs. Knowledge of this transient is necessary to perform a correct structural analysis of reactor containment. The containment system behavior is studied by changing the principal parameters which affect the transient (blow-down mass and energy release, suppression pool water temperature, vent pipe number and submergence, heat transfer coefficients). The first series of tests involved: A) 13 tests with break area of 1.8 cm 2 , B) 8 tests with break area of 20.0 cm 2 . The following experimental conditions were changed: position of the simulated break (from liquid or steam zone), water pressure (20-85 Kg/cm 2 ) and mass (45-70 Kg) in the vessel model. Tests A): the CONTEMPT codes correctly forecast the pressure-temperature history, both in dry- and in wet-well. Tests B): the experimental runs have shown that increasing of blow-down flowrate produces dry-well pressure spatial differences and anomalous vent pipe behavior. This results in damped oscillations of dry- and wet-well pressure, probably due to alternating air bubble over-expansion and collapse, and in vent pipe opening and reclosing. Dry-well pressure maxima at the end of blow-down are greater than those forecasted by currently applied codes: these codes use an homogeneous model, and do not take into account the above mentioned dynamic phenomena. In some tests other interesting phenomena were observed, such as some local pressure peaks in the suppression pool greater than dry-well pessure maxima at the end of blow-down. At present, all these phenomena are under study; they could be important for the structural analysis of containment systems

  18. Effect of corticotropin-releasing factor receptor antagonist on psychologically suppressed masculine sexual behavior in rats.

    Science.gov (United States)

    Miwa, Yoshiji; Nagase, Keiko; Oyama, Nobuyuki; Akino, Hironobu; Yokoyama, Osamu

    2011-03-01

    Corticotropin-releasing factor (CRF) coordinates various responses of the body to stress, and CRF receptors are important targets of treatment for stress-related disorders. To investigate the effect of a nonselective CRF receptor antagonist, astressin, on suppression of masculine sexual behavior by psychological stress in rats. First, we investigated the influence of psychological stress, induced 2 hours per day for three consecutive days, on sexual behavior. Then, rats were divided into 4 groups: a control group, an astressin administration group (A), a psychological stress loading group (PS), and a psychological stress loading and astressin administration group (PS + A). The rats were exposed to sham or psychological stress for three consecutive days. After the last stress loading, the rats were injected with vehicle or astressin, and their sexual behavior was observed. We also measured serum levels of adrenocorticotropic hormone (ACTH). The effects of astressin on sexual behavior and serum levels of ACTH in rats affected by psychological stress were determined. Sexual behavior was reduced after psychological stress loading. The PS rats had significantly longer mount, intromission, and ejaculation latencies and lower ejaculation frequency than did the control, A, and PS + A rats. The intromission latency and ejaculation frequency in the PS + A rats did not achieve the level observed in the controls. There was no significant difference in these parameters between the control and A rats. Serum ACTH levels were significantly lower in PS + A rats than in PS rats. Psychologically suppressed masculine sexual behavior could be partially recovered with astressin administration in rats. These data provide a rationale for the further study of CRF receptor antagonists as novel agents for treating psychological sexual disorders. © 2010 International Society for Sexual Medicine.

  19. Suppression of anomalous synchronization and nonstationary behavior of neural network under small-world topology

    Science.gov (United States)

    Boaretto, B. R. R.; Budzinski, R. C.; Prado, T. L.; Kurths, J.; Lopes, S. R.

    2018-05-01

    It is known that neural networks under small-world topology can present anomalous synchronization and nonstationary behavior for weak coupling regimes. Here, we propose methods to suppress the anomalous synchronization and also to diminish the nonstationary behavior occurring in weakly coupled neural network under small-world topology. We consider a network of 2000 thermally sensitive identical neurons, based on the model of Hodgkin-Huxley in a small-world topology, with the probability of adding non local connection equal to p = 0 . 001. Based on experimental protocols to suppress anomalous synchronization, as well as nonstationary behavior of the neural network dynamics, we make use of (i) external stimulus (pulsed current); (ii) biologic parameters changing (neuron membrane conductance changes); and (iii) body temperature changes. Quantification analysis to evaluate phase synchronization makes use of the Kuramoto's order parameter, while recurrence quantification analysis, particularly the determinism, computed over the easily accessible mean field of network, the local field potential (LFP), is used to evaluate nonstationary states. We show that the methods proposed can control the anomalous synchronization and nonstationarity occurring for weak coupling parameter without any effect on the individual neuron dynamics, neither in the expected asymptotic synchronized states occurring for large values of the coupling parameter.

  20. Conditioned suppression of sexual behavior in stallions and reversal with diazepam.

    Science.gov (United States)

    McDonnell, S M; Kenney, R M; Meckley, P E; Garcia, M C

    1985-06-01

    Sexual behavior dysfunction unaccompanied by detectable physical or endocrine abnormality is an important cause of reproductive failure among domestic stallions. Several authors have suggested that such dysfunction may be psychogenic, related to negative experience associated with intense handling and training. An experimental model of experience-related dysfunction was developed by exposing pony stallions to erection-contingent aversive conditioning. This resulted in rapid, specific suppression of sexual arousal and response similar to spontaneously occurring dysfunction. Subsequently, treatment with a CNS-active benzodiazepine derivative (diazepam) reversed these effects.

  1. Sleep duration and RSA suppression as predictors of internalizing and externalizing behaviors.

    Science.gov (United States)

    Cho, Sunghye; Philbrook, Lauren E; Davis, Elizabeth L; Buss, Kristin A

    2017-01-01

    Although the conceptual interplay among the biological and clinical features of sleep, arousal, and emotion regulation has been noted, little is understood about how indices of sleep duration and parasympathetic reactivity operate jointly to predict adjustment in early childhood. Using a sample of 123 toddlers, the present study examined sleep duration and RSA reactivity as predictors of internalizing and externalizing behaviors. Parents reported on children's sleep duration and adjustment. RSA reactivity was assessed via children's responses to fear-eliciting stimuli and an inhibitory control challenge. Findings demonstrated that greater RSA suppression to both types of tasks in combination with longer sleep duration was concurrently associated with less internalizing. In contrast, greater RSA augmentation to an inhibitory control task in the context of shorter sleep duration predicted more externalizing 1 year later. The significance of duration of toddlers' sleep as well as the context in which physiological regulatory difficulties occurs is discussed. © 2016 Wiley Periodicals, Inc.

  2. Behavioral experience induces zif268 expression in mature granule cells but suppresses its expression in immature granule cells

    Science.gov (United States)

    Huckleberry, Kylie A.; Kane, Gary A.; Mathis, Rita J.; Cook, Sarah G.; Clutton, Jonathan E.; Drew, Michael R.

    2015-01-01

    Thousands of neurons are born each day in the dentate gyrus (DG), but many of these cells die before reaching maturity. Both death and survival of adult-born neurons are regulated by neuronal activity in the DG. The immediate-early gene (IEG) zif268 appears to be an important mediator of these effects, as its expression can be induced by neural activity and knockout of zif268 impairs survival of adult-born neurons (Richardson et al., 1992; Veyrac et al., 2013). Despite the apparent importance of zif268 for adult neurogenesis, its behavior-induced expression has not been fully characterized in adult-born neurons. Here we characterize behavior-evoked expression of zif268 in mature and newborn dentate granule cells (DGCs). We first quantified zif268 expression in doublecortin-positive (DCX+) immature neurons and in the general granule cell population after brief exposure to a novel environment (NE). In the general granule cell population, zif268 expression peaked 1 h after NE exposure and returned to baseline by 8 h post-exposure. However, in the DCX+ cells, zif268 expression was suppressed relative to home cage for at least 8 h post-exposure. We next asked whether suppression of zif268 in DCX+ immature cells occurs in other behavioral paradigms that recruit the hippocampus. Exposure to Morris water maze (MWM) training, an enriched environment, or a NE caused approximately equal suppression of zif268 expression in DCX+ cells and approximately equal activation of zif268 expression among the general granule cell population. The same behavioral procedures activated zif268 expression in 6-week-old BrdU-labeled adult-born neurons, indicating that zif268 suppression is specific to immature neurons. Finally, we asked whether zif268 suppression varied as a function of age within the DCX+ population, which ranges in age from 0 to approximately 4 weeks. NE exposure had no significant effect on zif268 expression in 2- or 4-week-old BrdU-labeled neurons, but it significantly

  3. Behavioral performance follows the time course of neural facilitation and suppression during cued shifts of feature-selective attention.

    Science.gov (United States)

    Andersen, S K; Müller, M M

    2010-08-03

    A central question in the field of attention is whether visual processing is a strictly limited resource, which must be allocated by selective attention. If this were the case, attentional enhancement of one stimulus should invariably lead to suppression of unattended distracter stimuli. Here we examine voluntary cued shifts of feature-selective attention to either one of two superimposed red or blue random dot kinematograms (RDKs) to test whether such a reciprocal relationship between enhancement of an attended and suppression of an unattended stimulus can be observed. The steady-state visual evoked potential (SSVEP), an oscillatory brain response elicited by the flickering RDKs, was measured in human EEG. Supporting limited resources, we observed both an enhancement of the attended and a suppression of the unattended RDK, but this observed reciprocity did not occur concurrently: enhancement of the attended RDK started at 220 ms after cue onset and preceded suppression of the unattended RDK by about 130 ms. Furthermore, we found that behavior was significantly correlated with the SSVEP time course of a measure of selectivity (attended minus unattended) but not with a measure of total activity (attended plus unattended). The significant deviations from a temporally synchronized reciprocity between enhancement and suppression suggest that the enhancement of the attended stimulus may cause the suppression of the unattended stimulus in the present experiment.

  4. (+)-Borneol suppresses conditioned fear recall and anxiety-like behaviors in mice.

    Science.gov (United States)

    Cao, Bo; Ni, Huan-Yu; Li, Jun; Zhou, Ying; Bian, Xin-Lan; Tao, Yan; Cai, Cheng-Yun; Qin, Cheng; Wu, Hai-Yin; Chang, Lei; Luo, Chun-Xia; Zhu, Dong-Ya

    2018-01-08

    Fear- and anxiety-related psychiatric disorders have been one of the major chronic diseases afflicting patients for decades, and new compounds for treating such disorders remain to be developed. (+)-Borneol, a bicyclic monoterpene found in several species of Artemisia and Dipterocarpaceae, is widely used for anxiety, pain and anesthesia in Chinese medicine. Meanwhile, it can potentiate GABA (γ-aminobutyric acid) activity directly in recombinant GABAA receptors. The present study was to investigate the effects of (+)-Borneol on both contextual and cued fear recall. Interestingly, microinjection of (+)-Borneol into the dorsal hippocampus inhibited 24 h and 7 d contextual fear, whereas its infusion into ventral hippocampus only reduced 24 h cued fear responses. Moreover, microinjection of (+)-Borneol into dorsal but not ventral hippocampus suppressed anxiety-like behaviors in the open field test, light/dark exploration and the elevated plus maze test. As selective GABA A receptor antagonist bicuculline reversed the effect of (+)-Borneol on contextual fear paradigm and the drug potentiated GABA-evoked currents in acute hippocampus slices, modulation of the GABAergic neurotransmission may explain the effects of (+)-Borneol. Our findings suggest that (+)-Borneol can serve as a new therapeutic in fear- and anxiety-related disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Impact of maternal melatonin suppression on forced swim and tail suspension behavioral despair tests in adult offspring.

    Science.gov (United States)

    Voiculescu, S E; Rosca, A E; Zeca, V; Zagrean, L; Zagrean, A M

    2015-01-01

    Melatonin is an essential hormone, which regulates circadian rhythms and has antioxidative and anticarcinogenic effects. As melatonin secretion is suppressed by light, this effect was examined on the offspring of the Wistar rat females exposed to continuous light (500 lux) during the second half of the pregnancy (day 12 to 21). Control rats were kept under a 12:12 light-dark cycle. The resulted male offspring have been behaviorally assessed for depression after postnatal day 60 by using Forced Swim Test (FST) and Tail Suspension Test (TST). Animals resulted from the melatonin deprived pregnancies have developed an abnormal response in the TST, but a normal FST behavior. Also, TST active movement was different in the melatonin suppression group compared to the control group. These findings suggest that intrauterine melatonin deprivation might be linked to the depressive like behavior in adult male offspring.

  6. Ongoing ingestive behavior is rapidly suppressed by a preabsorptive, intestinal “bitter taste” cue

    Science.gov (United States)

    Davidson, Terry L.; Powley, Terry L.

    2011-01-01

    The discovery that cells in the gastrointestinal (GI) tract express the same molecular receptors and intracellular signaling components known to be involved in taste has generated great interest in potential functions of such post-oral “taste” receptors in the control of food intake. To determine whether taste cues in the GI tract are detected and can directly influence behavior, the present study used a microbehavioral analysis of intake, in which rats drank from lickometers that were programmed to simultaneously deliver a brief yoked infusion of a taste stimulus to the intestines. Specifically, in daily 30-min sessions, thirsty rats with indwelling intraduodenal catheters were trained to drink hypotonic (0.12 M) sodium chloride (NaCl) and simultaneously self-infuse a 0.12 M NaCl solution. Once trained, in a subsequent series of intestinal taste probe trials, rats reduced licking during a 6-min infusion period, when a bitter stimulus denatonium benzoate (DB; 10 mM) was added to the NaCl vehicle for infusion, apparently conditioning a mild taste aversion. Presentation of the DB in isomolar lithium chloride (LiCl) for intestinal infusions accelerated the development of the response across trials and strengthened the temporal resolution of the early licking suppression in response to the arrival of the DB in the intestine. In an experiment to evaluate whether CCK is involved as a paracrine signal in transducing the intestinal taste of DB, the CCK-1R antagonist devazepide partially blocked the response to intestinal DB. In contrast to their ability to detect and avoid the bitter taste in the intestine, rats did not modify their licking to saccharin intraduodenal probe infusions. The intestinal taste aversion paradigm developed here provides a sensitive and effective protocol for evaluating which tastants—and concentrations of tastants—in the lumen of the gut can control ingestion. PMID:21865540

  7. Ongoing ingestive behavior is rapidly suppressed by a preabsorptive, intestinal "bitter taste" cue.

    Science.gov (United States)

    Schier, Lindsey A; Davidson, Terry L; Powley, Terry L

    2011-11-01

    The discovery that cells in the gastrointestinal (GI) tract express the same molecular receptors and intracellular signaling components known to be involved in taste has generated great interest in potential functions of such post-oral "taste" receptors in the control of food intake. To determine whether taste cues in the GI tract are detected and can directly influence behavior, the present study used a microbehavioral analysis of intake, in which rats drank from lickometers that were programmed to simultaneously deliver a brief yoked infusion of a taste stimulus to the intestines. Specifically, in daily 30-min sessions, thirsty rats with indwelling intraduodenal catheters were trained to drink hypotonic (0.12 M) sodium chloride (NaCl) and simultaneously self-infuse a 0.12 M NaCl solution. Once trained, in a subsequent series of intestinal taste probe trials, rats reduced licking during a 6-min infusion period, when a bitter stimulus denatonium benzoate (DB; 10 mM) was added to the NaCl vehicle for infusion, apparently conditioning a mild taste aversion. Presentation of the DB in isomolar lithium chloride (LiCl) for intestinal infusions accelerated the development of the response across trials and strengthened the temporal resolution of the early licking suppression in response to the arrival of the DB in the intestine. In an experiment to evaluate whether CCK is involved as a paracrine signal in transducing the intestinal taste of DB, the CCK-1R antagonist devazepide partially blocked the response to intestinal DB. In contrast to their ability to detect and avoid the bitter taste in the intestine, rats did not modify their licking to saccharin intraduodenal probe infusions. The intestinal taste aversion paradigm developed here provides a sensitive and effective protocol for evaluating which tastants-and concentrations of tastants-in the lumen of the gut can control ingestion.

  8. Phase-specific Surround suppression in Mouse Primary Visual Cortex Correlates with Figure Detection Behavior Based on Phase Discontinuity.

    Science.gov (United States)

    Li, Fengling; Jiang, Weiqian; Wang, Tian-Yi; Xie, Taorong; Yao, Haishan

    2018-05-21

    In the primary visual cortex (V1), neuronal responses to stimuli within the receptive field (RF) are modulated by stimuli in the RF surround. A common effect of surround modulation is surround suppression, which is dependent on the feature difference between stimuli within and surround the RF and is suggested to be involved in the perceptual phenomenon of figure-ground segregation. In this study, we examined the relationship between feature-specific surround suppression of V1 neurons and figure detection behavior based on figure-ground feature difference. We trained freely moving mice to perform a figure detection task using figure and ground gratings that differed in spatial phase. The performance of figure detection increased with the figure-ground phase difference, and was modulated by stimulus contrast. Electrophysiological recordings from V1 in head-fixed mice showed that the increase in phase difference between stimuli within and surround the RF caused a reduction in surround suppression, which was associated with an increase in V1 neural discrimination between stimuli with and without RF-surround phase difference. Consistent with the behavioral performance, the sensitivity of V1 neurons to RF-surround phase difference could be influenced by stimulus contrast. Furthermore, inhibiting V1 by optogenetically activating either parvalbumin (PV)- or somatostatin (SOM)-expressing inhibitory neurons both decreased the behavioral performance of figure detection. Thus, the phase-specific surround suppression in V1 represents a neural correlate of figure detection behavior based on figure-ground phase discontinuity. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

  9. Intentional suppression can lead to a reduction of memory strength: Behavioral and electrophysiological findings

    Directory of Open Access Journals (Sweden)

    Gerd Thomas Waldhauser

    2012-10-01

    Full Text Available Previous research has shown that the intentional suppression of unwanted memories can lead to forgetting in later memory tests. However, the mechanisms underlying this effect remain unclear. This study employed recognition memory testing and event-related potentials (ERPs to investigate whether intentional suppression leads to the inhibition of memory representations at an item level. In a think/no-think experiment, participants were cued to either suppress (no-think condition or retrieve (think condition previously learned words, 18 or 0 times. Performance in a final recognition test was significantly reduced for repeatedly suppressed no-think items when compared to the baseline, zero-repetition condition. ERPs recorded during the suppression of no-think items were significantly more negative-going in a time-window around 300 ms when compared to ERPs in the think condition. This reduction correlated with later recognition memory impairment. Furthermore, ERPs to no-think items from 225-450 ms were more negative-going in later phases of the experiment, suggesting a gradual reduction of memory strength with repeated suppression attempts. These effects were dissociable from correlates of recollection (500-600 ms and inhibitory control (450-500 ms that did not vary over the time-course of the experiment and appeared to be under strategic control. Our results give strong evidence that the no-think manipulation involves inhibition of memory representations at an item level.

  10. Behavioral experience induces zif268 expression in mature granule cells but suppresses its expression in immature granule cells

    Directory of Open Access Journals (Sweden)

    Kylie A. Huckleberry

    2015-08-01

    Full Text Available Thousands of neurons are born each day in the dentate gyrus (DG, but many of these cells die before reaching maturity. Both death and survival of adult-born neurons are regulated by neuronal activity in DG. The immediate-early gene (IEG zif268 is an important mediator of these effects, as its expression is induced by neural activity and knockout of zif268 impairs survival of adult-born neurons (Veyrac et al., 2013. Despite the apparent importance of zif268 for adult neurogenesis, its behavior-induced expression has not been fully characterized in adult-born neurons. Here we characterize behavior-evoked expression of zif268 in mature and newborn dentate granule cells (DGCs. In the general granule cell population, zif268 expression peaked 1 hour after novel environment exposure and returned to baseline by 8 hours post-exposure. However, in the doublecortin-positive (DCX+ immature neurons, zif268 expression was suppressed relative to home cage for at least 8 hours post-exposure. We next determined that exposure to water maze training, an enriched environment, or a novel environment caused approximately equal suppression of zif268 expression in DCX+ cells and approximately equal activation of zif268 in the general DGC population and in 6-week-old adult-born neurons. Finally, we asked whether zif268 suppression varied as a function of age within the DCX+ population, which ranges in age from 0 to approximately 4 weeks. Novel environment exposure had no significant effect on zif268 expression in 2- or 4-week-old BrdU-labeled neurons, but it significantly suppressed zif268 expression in 3-week-old neurons. In summary, behavioral experience transiently activated expression of zif268 in mature DGCs but caused a more long-lasting suppression of zif268 expression in immature, adult-born DGCs. We hypothesize that zif268 suppression inhibits memory-related synaptic plasticity in immature DGCs or mediates learning-induced apoptosis of immature adult

  11. Suppression of oxidative stress and 5-lipoxygenase activation by edaravone improves depressive-like behavior after concussion.

    Science.gov (United States)

    Higashi, Youichirou; Hoshijima, Michihiro; Yawata, Toshio; Nobumoto, Atsuya; Tsuda, Masayuki; Shimizu, Takahiro; Saito, Motoaki; Ueba, Tetuya

    2014-10-15

    Brain concussions are a serious public concern and are associated with neuropsychiatric disorders, such as depression. Patients with concussion who suffer from depression often experience distress. Nevertheless, few pre-clinical studies have examined concussion-induced depression, and there is little information regarding its pharmacological management. Edaravone, a free radical scavenger, can exert neuroprotective effects in several animal models of neurological disorders. However, the effectiveness of edaravone in animal models of concussion-induced depression remains unclear. In this study, we examined whether edaravone could prevent concussion-induced depression. Mice were subjected to a weight-drop injury and intravenously administered edaravone (3.0 mg/kg) or vehicle immediately after impact. Serial magnetic resonance imaging showed no abnormalities of the cerebrum on diffusion T1- and T2-weighted images. We found that edaravone suppressed concussion-induced depressive-like behavior in the forced swim test, which was accompanied by inhibition of increased hippocampal and cortical oxidative stress (OS) and suppression of 5-lipoxygenase (5-LOX) translocation to the nuclear envelope in hippocampal astrocytes. Hippocampal OS in concussed mice was also prevented by the nicotinamide adenine dinucleotide phosphate oxidase inhibitor, apocynin, and administration of BWB70C, a 5-LOX inhibitor, immediately and 24 h after injury prevented depressive-like behaviors in concussed mice. Further, antidepressant effects of edaravone were observed in mice receiving 1.0 or 3.0 mg/kg of edaravone immediately after impact, but not at a lower dose of 0.1 mg/kg. This antidepressant effect persisted up to 1 h after impact, whereas edaravone treatment at 3 h after impact had no effect on concussion-induced depressive-like behavior. These results suggest that edaravone protects against concussion-induced depression, and this protection is mediated by suppression of OS and 5

  12. Moral and Sexual Disgust Suppress Sexual Risk Behaviors among Men Who Have Sex with Men in China

    Science.gov (United States)

    Zhang, Jing; Zheng, Lijun; Zheng, Yong

    2017-01-01

    Increasingly more men who have sex with men (MSM) are engaging in sexual risk taking in China in recent years. Given the high rates of HIV infection among MSM in China, it is urgent that we understand the factors that influence MSM's practice of sexual risk taking. Disgust sensitivity, which elicits a behavioral avoidance response, has the potential to influence risky sexual behavior. The present study examined the relationship between disgust sensitivity and sexual risk behavior among MSM in China. Men (n = 584) who reported having anal intercourse in the previous 6 months were recruited from the Internet. Two indicators of sexual risk behaviors were measured: condom use and the number of sex partners. The results indicated that moral disgust was positively associated with condom use, with MSM who had higher moral disgust being more likely to use condoms than others did. Sexual disgust was positively associated with the number of sex partners, with MSM who had higher sexual disgust having fewer male sex partners than others did. Sexual and moral disgust sensitivity significantly predicted HIV testing. Our study verified that sexual and moral disgust suppressed sexual risk behaviors and promoted HIV testing. Moral and sexual education should be incorporated in future strategies for HIV prevention and encouragement of safe sex behaviors among MSM in China. PMID:28119646

  13. On the existence of a threshold for preventive behavioral responses to suppress epidemic spreading.

    Science.gov (United States)

    Sahneh, Faryad Darabi; Chowdhury, Fahmida N; Scoglio, Caterina M

    2012-01-01

    The spontaneous behavioral responses of individuals to the progress of an epidemic are recognized to have a significant impact on how the infection spreads. One observation is that, even if the infection strength is larger than the classical epidemic threshold, the initially growing infection can diminish as the result of preventive behavioral patterns adopted by the individuals. In order to investigate such dynamics of the epidemic spreading, we use a simple behavioral model coupled with the individual-based SIS epidemic model where susceptible individuals adopt a preventive behavior when sensing infection. We show that, given any infection strength and contact topology, there exists a region in the behavior-related parameter space such that infection cannot survive in long run and is completely contained. Several simulation results, including a spreading scenario in a realistic contact network from a rural district in the State of Kansas, are presented to support our analytical arguments.

  14. Nocturnal to Diurnal Switches with Spontaneous Suppression of Wheel-Running Behavior in a Subterranean Rodent

    Science.gov (United States)

    Tachinardi, Patricia; Tøien, Øivind; Valentinuzzi, Veronica S.; Buck, C. Loren; Oda, Gisele A.

    2015-01-01

    Several rodent species that are diurnal in the field become nocturnal in the lab. It has been suggested that the use of running-wheels in the lab might contribute to this timing switch. This proposition is based on studies that indicate feed-back of vigorous wheel-running on the period and phase of circadian clocks that time daily activity rhythms. Tuco-tucos (Ctenomys aff. knighti) are subterranean rodents that are diurnal in the field but are robustly nocturnal in laboratory, with or without access to running wheels. We assessed their energy metabolism by continuously and simultaneously monitoring rates of oxygen consumption, body temperature, general motor and wheel running activity for several days in the presence and absence of wheels. Surprisingly, some individuals spontaneously suppressed running-wheel activity and switched to diurnality in the respirometry chamber, whereas the remaining animals continued to be nocturnal even after wheel removal. This is the first report of timing switches that occur with spontaneous wheel-running suppression and which are not replicated by removal of the wheel. PMID:26460828

  15. Nocturnal to Diurnal Switches with Spontaneous Suppression of Wheel-Running Behavior in a Subterranean Rodent.

    Directory of Open Access Journals (Sweden)

    Patricia Tachinardi

    Full Text Available Several rodent species that are diurnal in the field become nocturnal in the lab. It has been suggested that the use of running-wheels in the lab might contribute to this timing switch. This proposition is based on studies that indicate feed-back of vigorous wheel-running on the period and phase of circadian clocks that time daily activity rhythms. Tuco-tucos (Ctenomys aff. knighti are subterranean rodents that are diurnal in the field but are robustly nocturnal in laboratory, with or without access to running wheels. We assessed their energy metabolism by continuously and simultaneously monitoring rates of oxygen consumption, body temperature, general motor and wheel running activity for several days in the presence and absence of wheels. Surprisingly, some individuals spontaneously suppressed running-wheel activity and switched to diurnality in the respirometry chamber, whereas the remaining animals continued to be nocturnal even after wheel removal. This is the first report of timing switches that occur with spontaneous wheel-running suppression and which are not replicated by removal of the wheel.

  16. Septal Glucagon-Like Peptide 1 Receptor Expression Determines Suppression of Cocaine-Induced Behavior

    Science.gov (United States)

    Harasta, Anne E; Power, John M; von Jonquieres, Georg; Karl, Tim; Drucker, Daniel J; Housley, Gary D; Schneider, Miriam; Klugmann, Matthias

    2015-01-01

    Glucagon-like peptide 1 (GLP-1) and its receptor GLP-1R are a key component of the satiety signaling system, and long-acting GLP-1 analogs have been approved for the treatment of type-2 diabetes mellitus. Previous reports demonstrate that GLP-1 regulates glucose homeostasis alongside the rewarding effects of food. Both palatable food and illicit drugs activate brain reward circuitries, and pharmacological studies suggest that central nervous system GLP-1 signaling holds potential for the treatment of addiction. However, the role of endogenous GLP-1 in the attenuation of reward-oriented behavior, and the essential domains of the mesolimbic system mediating these beneficial effects, are largely unknown. We hypothesized that the central regions of highest Glp-1r gene activity are essential in mediating responses to drugs of abuse. Here, we show that Glp-1r-deficient (Glp-1r−/−) mice have greatly augmented cocaine-induced locomotor responses and enhanced conditional place preference compared with wild-type (Glp-1r+/+) controls. Employing mRNA in situ hybridization we located peak Glp-1r mRNA expression in GABAergic neurons of the dorsal lateral septum, an anatomical site with a crucial function in reward perception. Whole-cell patch-clamp recordings of dorsal lateral septum neurons revealed that genetic Glp-1r ablation leads to increased excitability of these cells. Viral vector-mediated Glp-1r gene delivery to the dorsal lateral septum of Glp-1r−/− animals reduced cocaine-induced locomotion and conditional place preference to wild-type levels. This site-specific genetic complementation did not affect the anxiogenic phenotype observed in Glp-1r−/− controls. These data reveal a novel role of GLP-1R in dorsal lateral septum function driving behavioral responses to cocaine. PMID:25669605

  17. Suppression of growth and invasive behavior of human prostate cancer cells by ProstaCaid™: mechanism of activity.

    Science.gov (United States)

    Jiang, Jiahua; Eliaz, Isaac; Sliva, Daniel

    2011-06-01

    Since the use of dietary supplements as alternative treatments or adjuvant therapies in cancer treatment is growing, a scientific verification of their biological activity and the detailed mechanisms of their action are necessary for the acceptance of dietary supplements in conventional cancer treatments. In the present study we have evaluated the anti-cancer effects of dietary supplement ProstaCaid™ (PC) which contains mycelium from medicinal mushrooms (Ganoderma lucidum, Coriolus versicolor, Phellinus linteus), saw palmetto berry, pomegranate, pumpkin seed, green tea [40% epigallocatechin-3-gallate (EGCG)], Japanese knotweed (50% resveratrol), extracts of turmeric root (BCM-95®), grape skin, pygeum bark, sarsaparilla root, Scutellaria barbata, eleuthero root, Job's tears, astragalus root, skullcap, dandelion, coptis root, broccoli, and stinging nettle, with purified vitamin C, vitamin D3, selenium, quercetin, citrus bioflavonoid complex, β sitosterolzinc, lycopene, α lipoic acid, boron, berberine and 3.3'-diinodolymethane (DIM). We show that PC treatment resulted in the inhibition of cell proliferation of the highly invasive human hormone refractory (independent) PC-3 prostate cancer cells in a dose- and time-dependent manner with IC50 56.0, 45.6 and 39.0 µg/ml for 24, 48 and 72 h, respectively. DNA-microarray analysis demonstrated that PC inhibits proliferation through the modulation of expression of CCND1, CDK4, CDKN1A, E2F1, MAPK6 and PCNA genes. In addition, PC also suppresses metastatic behavior of PC-3 by the inhibition of cell adhesion, cell migration and cell invasion, which was associated with the down-regulation of expression of CAV1, IGF2, NR2F1, and PLAU genes and suppressed secretion of the urokinase plasminogen activator (uPA) from PC-3 cells. In conclusion, the dietary supplement PC is a promising natural complex with the potency to inhibit invasive human prostate cancer.

  18. Inhibition of calcineurin inhibits the desensitization of capsaicin evoked currents in cultured dorsal root ganglion neurones from adult rats

    NARCIS (Netherlands)

    Docherty, RJ; Yeats, JC; Bevan, S; Boddeke, HWGM

    Capsaicin activates a non-specific cation conductance in mammalian sensory neurones. If capsaicin is applied continuously or repeatedly then there is a progressive decline in responsiveness. We have studied the mechanism of this desensitization using electrophysiological methods in cultured dorsal

  19. Effects of experimental suppression of active (REM) sleep during early development upon adult brain and behavior in the rat.

    Science.gov (United States)

    Mirmiran, M; Scholtens, J; van de Poll, N E; Uylings, H B; van der Gugten, J; Boer, G J

    1983-04-01

    In order to test the hypothesis that active sleep (AS) is important for the normal development of the central nervous system, 3 different deprivation methods were applied to male Wistar rat pups during the first month of life. Daily injection of clomipramine from 8 to 21 days of age reduced the high level of AS to less than the adult value throughout most of the experimental period. Administration of clonidine from 8 to 21 days of life induced an almost total suppression of AS. Instrumental deprivation, using the 'pendulum' method, led to a significant (but less severe) AS reduction during 2-4 weeks of postnatal age. Open-field behavior testing in adulthood revealed a higher than normal level of ambulation in all 3 experimental groups. Masculine sexual responses were deficient, due to a low level of both mounts and ejaculations, in both clomipramine- and clonidine-treated animals. Neither passive avoidance learning nor dark preference tests revealed any differences between the experimental and control rats. Sleep observations showed that there was an abnormally high incidence of large myoclonic jerks during AS in both clomipramine- and clonidine-treated rats. Subsequent measurement of regional brain weights showed a significant reduction in the cerebral cortex and medulla oblongata, as compared with the respective control groups, in both the clomipramine- and the clonidine-treated rats. In addition, DNA and protein determination in the affected brain areas showed a proportional reduction in the cortex and in the medulla. These results demonstrate that interference with normal functioning either of AS per se or of specific monoaminergic transmitter systems during early development can produce long-lasting behavioral as well as brain morphological and biochemical abnormalities in later life.

  20. Behavioral performance follows the time course of neural facilitation and suppression during cued shifts of feature-selective attention

    OpenAIRE

    Andersen, S. K.; Müller, M. M.

    2010-01-01

    A central question in the field of attention is whether visual processing is a strictly limited resource, which must be allocated by selective attention. If this were the case, attentional enhancement of one stimulus should invariably lead to suppression of unattended distracter stimuli. Here we examine voluntary cued shifts of feature-selective attention to either one of two superimposed red or blue random dot kinematograms (RDKs) to test whether such a reciprocal relationship between enhanc...

  1. Suppressed Belief

    Directory of Open Access Journals (Sweden)

    Komarine Romdenh-Romluc

    2009-12-01

    Full Text Available Moran’s revised conception of conscious belief requires us to reconceptualise suppressed belief. The work of Merleau-Ponty offers a way to do this. His account of motor-skills allows us to understand suppressed beliefs as pre-reflective ways of dealing with the world.

  2. Notch4 Signaling Induces a Mesenchymal–Epithelial–like Transition in Melanoma Cells to Suppress Malignant Behaviors

    Science.gov (United States)

    Rad, Ehsan Bonyadi; Hammerlindl, Heinz; Wels, Christian; Popper, Ulrich; Menon, Dinoop Ravindran; Breiteneder, Heimo; Kitzwoegerer, Melitta; Hafner, Christine; Herlyn, Meenhard; Bergler, Helmut; Schaider, Helmut

    2016-01-01

    The effects of Notch signaling are context-dependent and both oncogenic and tumor-suppressive functions have been described. Notch signaling in melanoma is considered oncogenic, but clinical trials testing Notch inhibition in this malignancy have not proved successful. Here, we report that expression of the constitutively active intracellular domain of Notch4 (N4ICD) in melanoma cells triggered a switch from a mesenchymal-like parental phenotype to an epithelial-like phenotype. The epithelial-like morphology was accompanied by strongly reduced invasive, migratory, and proliferative properties concomitant with the downregulation of epithelial–mesenchymal transition markers Snail2 (SNAI2), Twist1, vimentin (VIM), and MMP2 and the reexpression of E-cadherin (CDH1). The N4ICD-induced phenotypic switch also resulted in significantly reduced tumor growth in vivo. Immunohistochemical analysis of primary human melanomas and cutaneous metastases revealed a significant correlation between Notch4 and E-cadherin expression. Mechanistically, we demonstrate that N4ICD induced the expression of the transcription factors Hey1 and Hey2, which bound directly to the promoter regions of Snail2 and Twist1 and repressed gene transcription, as determined by EMSA and luciferase assays. Taken together, our findings indicate a role for Notch4 as a tumor suppressor in melanoma, uncovering a potential explanation for the poor clinical efficacy of Notch inhibitors observed in this setting. PMID:26801977

  3. Kaempferol, a phytoestrogen, suppressed triclosan-induced epithelial-mesenchymal transition and metastatic-related behaviors of MCF-7 breast cancer cells.

    Science.gov (United States)

    Lee, Geum-A; Choi, Kyung-Chul; Hwang, Kyung-A

    2017-01-01

    As a phytoestrogen, kaempferol is known to play a chemopreventive role inhibiting carcinogenesis and cancer progression. In this study, the influences of triclosan, an anti-bacterial agent recently known for an endocrine disrupting chemical (EDC), and kaempferol on breast cancer progression were examined by measuring their effects on epithelial-mesenchymal transition (EMT) and metastatic-related behaviors of MCF-7 breast cancer cells. Morphological changes of MCF-7 cells were observed, and a wound-healing assay was performed after the treatment of triclosan and kaempferol. The effects of triclosan and kaempferol on protein expression of EMT-related markers such as E-cadherin, N-cadherin, Snail, and Slug and metastasis-related markers such as cathepsin B, D, MMP-2 and -9 were investigated by Western blot assay. In microscopic observations, triclosan (10 -6 M) or E2 (10 -9 M) induced transition to mesenchymal phenotype of MCF-7 cells compared with the control. Co-treatment of ICI 182,780 (10 -8 M), an ER antagonist, or kaempferol (25μM) with E2 or triclosan restored the cellular morphology to an epithelial phenotype. In a wound-healing scratch and a transwell migration assay, triclosan enhanced migration and invasion of MCF-7 cells, but co-treatment of kaempferol or ICI 182,780 reduced the migration and invasion ability of MCF-7 cells to the control level. In addition, kaempferol effectively suppressed E2 or triclosan-induced protein expressions of EMT and metastasis promoting markers. Taken together, triclosan may be a distinct xenoestrogenic EDC to promote EMT, migration, and invasion of MCF-7 breast cancer cells through ER. On the other hand, kaempferol can be an alternative chemopreventive agent to effectively suppress the metastatic behavior of breast cancer induced by an endogenous estrogen as well as exogenous xenoestrogenic compounds including triclosan. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Early-life exposure to Tris(1,3-dichloroisopropyl) phosphate induces dose-dependent suppression of sexual behavior in male rats.

    Science.gov (United States)

    Kamishima, Manami; Hattori, Tatsuya; Suzuki, Go; Matsukami, Hidenori; Komine, Chiaki; Horii, Yasuyuki; Watanabe, Gen; Oti, Takumi; Sakamoto, Hirotaka; Soga, Tomoko; Parhar, Ishwar S; Kondo, Yasuhiko; Takigami, Hidetaka; Kawaguchi, Maiko

    2018-05-01

    Exposure to endocrine-disrupting chemicals may adversely affect animals, particularly during development. Tris(1,3-dichloroisopropyl) phosphate (TDCIPP) is an organophosphate with anti-androgen function in vitro that is present in indoor dust at relatively high concentrations. In male rats, androgens are necessary for the development of reproductive organs, as well as the endocrine and central nervous systems. However, we currently do not know the exact effects of TDCIPP exposure through suckling on subsequent reproductive behavior in males. Here, we show that TDCIPP exposure (25-250 mg kg -1 via oral administration over 28 consecutive days post-birth) suppressed male sexual behavior and reduced testes size. These changes were dose-dependent and appeared first in adults rather than in juveniles. These results demonstrate that TDCIPP exposure led to normal body growth and appearance in juveniles, but disrupted the endocrine system and physiology in adults. Therefore, assays should be performed using adult animals to ensure accuracy, and to confirm the influence of chemical substances given during early mammalian life. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Interocular suppression

    Science.gov (United States)

    Tuna, Ana Rita; Almeida Neves Carrega, Filipa; Nunes, Amélia Fernandes

    2017-08-01

    The objective of this work is to quantify the suppressive imbalance, based on the manipulation of ocular luminance, between a group of subjects with normal binocular vision and a group of subjects with amblyopia. The result reveals that there are statistically significant differences in interocular dominance between two groups, evidencing a greater suppressive imbalance in amblyopic subjects. The technique used, proved to be a simple, easy to apply and economic method, for quantified ocular dominance. It is presented as a technique with the potential to accompany subjects with a marked dominance in one of the eyes that makes fusion difficult.

  6. Suppression of Remodeling Behaviors with Arachidonic Acid Modification for Enhanced in vivo Antiatherogenic Efficacies of Lovastatin-loaded Discoidal Recombinant High Density Lipoprotein.

    Science.gov (United States)

    He, Hongliang; Zhang, Mengyuan; Liu, Lisha; Zhang, Shuangshuang; Liu, Jianping; Zhang, Wenli

    2015-10-01

    A series of in vitro evaluation in our previous studies had proved that arachidonic acid (AA) modification could suppress the remodeling behaviors of lovastatin-loaded discoidal reconstituted high density lipoprotein (LT-d-rHDL) by restraining the reactivity with lecithin cholesterol acyltransferase (LCAT) for reducing undesired drug leakage. This study focuses on the investigation of AA-modified LT-d-rHDL (AA-LT-d-rHDL) in atherosclerotic New Zealand White (NZW) rabbit models to explore whether AA modification could enhance drug targeting delivery and improve antiatherogenic efficacies in vivo. After pharmacokinetics of AA-LT-d-rHDL modified with different AA amount were investigated in atherosclerotic NZW rabbits, atherosclerotic lesions targeting property was assessed by ex vivo imaging of aortic tree and drug distribution. Furthermore, their antiatherogenic efficacies were elaborately evaluated and compared by typical biochemical indices. With AA modification amount augmenting, circulation time of AA-LT-d-rHDL was prolonged, and drug accumulation in the target locus was increased, eventually the significant appreciation in antiatherogenic efficacies were further supported by lower level of bad cholesterol, decreased atherosclerotic lesions areas and mean intima-media thickness (MIT), markedly attenuated matrix metalloproteinase-9 (MMP-9) protein expression and macrophage infiltration. This proof-of-concept study demonstrated that AA-LT-d-rHDL could enhance drug accumulation in atherosclerotic lesion and impede atherosclerosis progression more effectively.

  7. Targeting Oxidative Stress, Cytokines and Serotonin Interactions Via Indoleamine 2, 3 Dioxygenase by Coenzyme Q10: Role in Suppressing Depressive Like Behavior in Rats.

    Science.gov (United States)

    Abuelezz, Sally A; Hendawy, Nevien; Magdy, Yosra

    2017-06-01

    Depression is a major health problem in which oxidative stress and inflammation are inextricably connected in its pathophysiology. Coenzyme Q10 (CoQ10) is an important anti-oxidant compound with anti-inflammatory and neuro-protective properties. This study was designed to investigate the hypothesis that CoQ10 by its anti-oxidant and anti-inflammatory potentials can alleviate depressive- like behavior by restoring the balance of the tryptophan catabolites kynurenine/serotonin toward the serotonin pathway by down-regulation of hippocampal indoleamine 2,3-dioxygenase 1 (IDO-1). Depressive-like behavior was induced by chronic unpredictable mild stress (CUMS) protocol including food or water deprivation, cage tilting, reversed light cycle etc. Male Wistar rats were randomly divided into five groups; Control, CUMS, CUMS and CoQ10 (50,100 and 200 mg/kg/day i.p. respectively) groups. CoQ10 effects on different behavioral and biochemical tests were analyzed. CoQ10 showed significant antidepressant efficacy, as evidenced by significantly decreased stress induced changes to forced swimming challenge and open field test, as well as attenuating raised corticosterone level and adrenal glands weight. The anti-oxidant effect of CoQ10 was exhibited by its ability to significantly reduce hippocampal elevated malondialdehyde and 4-hydroxynonenal levels and elevate the reduced glutathione and catalase levels. CoQ10 significantly reduced different pro-inflammatory cytokines levels including interleukin (IL)-1β, IL-2, IL-6 and tumor necrosis factor-α. It suppressed hippocampal IDO-1 and subsequent production of kynurenine and enhanced the hippocampal contents of tryptophan and serotonin. Immunohistochemical analysis revealed that CoQ10 was able to attenuate the elevated microglial CD68 and elevate the astrocyte glial fibrillary acidic protein compared to CUMS group. CoQ10 exhibited antidepressant-like effects on rats exposed to CUMS. This could be attributed to its ability to reduce

  8. The μ opioid agonist morphine modulates potentiation of capsaicin-evoked TRPV1 responses through a cyclic AMP-dependent protein kinase A pathway

    Directory of Open Access Journals (Sweden)

    Roberts-Thomson Sarah J

    2006-07-01

    Full Text Available Abstract Background The vanilloid receptor 1 (TRPV1 is critical in the development of inflammatory hyperalgesia. Several receptors including G-protein coupled prostaglandin receptors have been reported to functionally interact with the TRPV1 through a cAMP-dependent protein kinase A (PKA pathway to potentiate TRPV1-mediated capsaicin responses. Such regulation may have significance in inflammatory pain. However, few functional receptor interactions that inhibit PKA-mediated potentiation of TRPV1 responses have been described. Results In the present studies we investigated the hypothesis that the μ opioid receptor (MOP agonist morphine can modulate forskolin-potentiated capsaicin responses through a cAMP-dependent PKA pathway. HEK293 cells were stably transfected with TRPV1 and MOP, and calcium (Ca2+ responses to injection of the TRPV1 agonist capsaicin were monitored in Fluo-3-loaded cells. Pre-treatment with morphine did not inhibit unpotentiated capsaicin-induced Ca2+ responses but significantly altered capsaicin responses potentiated by forskolin. TRPV1-mediated Ca2+ responses potentiated by the direct PKA activator 8-Br-cAMP and the PKC activator Phorbol-12-myristate-13-acetatewere not modulated by morphine. Immunohistochemical studies confirmed that the TRPV1 and MOP are co-expressed on cultured Dorsal Root Ganglion neurones, pointing towards the existence of a functional relationship between the G-protein coupled MOP and nociceptive TRPV1. Conclusion The results presented here indicate that the opioid receptor agonist morphine acts via inhibition of adenylate cyclase to inhibit PKA-potentiated TRPV1 responses. Targeting of peripheral opioid receptors may therefore have therapeutic potential as an intervention to prevent potentiation of TRPV1 responses through the PKA pathway in inflammation.

  9. Suppressed invasive and migratory behaviors of SW1353 chondrosarcoma cells through the regulation of Src, Rac1 GTPase, and MMP13.

    Science.gov (United States)

    Xu, Wenxiao; Wan, Qiaoqiao; Na, Sungsoo; Yokota, Hiroki; Yan, Jing-Long; Hamamura, Kazunori

    2015-12-01

    Chondrosarcoma is the second frequent type of primary bone cancer. In response to stress to the endoplasmic reticulum, activation of eIF2α-mediated signaling is reported to induce apoptosis. However, its effects on invasive and migratory behaviors of chondrosarcoma have not been understood. Focusing on potential roles of Src kinase, Rac1 GTPase, and MMP13, we investigated eIF2α-driven regulation of SW1353 chondrosarcoma cells. In particular, we employed two chemical agents (salubrinal, Sal; and guanabenz, Gu) that elevate the level of eIF2α phosphorylation. The result revealed that both Sal and Gu reduced invasion and motility of SW1353 chondrosarcoma cells in a dose dependent manner. Live imaging using a fluorescent resonance energy transfer (FRET) technique showed that Sal and Gu downregulated activities of Src kinase as well as Rac1 GTPase in an eIF2α dependent manner. RNA interference experiments supported an eIF2α-mediated regulatory network in the inhibitory role of Sal and Gu. Partial silencing of MMP13 also suppressed malignant phenotypes of SW1353 chondrosarcoma cells. However, MMP13 was not regulated via eIF2α since administration of Sal but not Gu reduced expression of MMP13. In summary, we demonstrate that eIF2α dependent and independent pathways regulate invasion and motility of SW1353 chondrosarcoma cells, and inactivation of Src, Rac1, and MMP13 by Sal could provide a potential adjuvant therapy for combating metastatic chondrosarcoma cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. A novel p38α MAPK inhibitor suppresses brain proinflammatory cytokine up-regulation and attenuates synaptic dysfunction and behavioral deficits in an Alzheimer's disease mouse model

    Directory of Open Access Journals (Sweden)

    McNamara Laurie K

    2007-09-01

    Full Text Available Abstract Background An accumulating body of evidence is consistent with the hypothesis that excessive or prolonged increases in proinflammatory cytokine production by activated glia is a contributor to the progression of pathophysiology that is causally linked to synaptic dysfunction and hippocampal behavior deficits in neurodegenerative diseases such as Alzheimer's disease (AD. This raises the opportunity for the development of new classes of potentially disease-modifying therapeutics. A logical candidate CNS target is p38α MAPK, a well-established drug discovery molecular target for altering proinflammatory cytokine cascades in peripheral tissue disorders. Activated p38 MAPK is seen in human AD brain tissue and in AD-relevant animal models, and cell culture studies strongly implicate p38 MAPK in the increased production of proinflammatory cytokines by glia activated with human amyloid-beta (Aβ and other disease-relevant stressors. However, the vast majority of small molecule drugs do not have sufficient penetrance of the blood-brain barrier to allow their use as in vivo research tools or as therapeutics for neurodegenerative disorders. The goal of this study was to test the hypothesis that brain p38α MAPK is a potential in vivo target for orally bioavailable, small molecules capable of suppressing excessive cytokine production by activated glia back towards homeostasis, allowing an improvement in neurologic outcomes. Methods A novel synthetic small molecule based on a molecular scaffold used previously was designed, synthesized, and subjected to analyses to demonstrate its potential in vivo bioavailability, metabolic stability, safety and brain uptake. Testing for in vivo efficacy used an AD-relevant mouse model. Results A novel, CNS-penetrant, non-toxic, orally bioavailable, small molecule inhibitor of p38α MAPK (MW01-2-069A-SRM was developed. Oral administration of the compound at a low dose (2.5 mg/kg resulted in attenuation of

  11. Structural, magnetic and microwave absorption behavior of Co-Zr substituted strontium hexaferrites prepared using tartaric acid fuel for electromagnetic interference suppression

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Prabhjyot, E-mail: prabhjyot.2525@gmail.com [Department of Chemistry, Centre for Advanced Studies-I, Guru Nanak Dev University, Amritsar 143005 (India); Chawla, S.K., E-mail: sschawla118@gmail.com [Department of Chemistry, Centre for Advanced Studies-I, Guru Nanak Dev University, Amritsar 143005 (India); Narang, Sukhleen Bindra, E-mail: sukhleen2@yahoo.com [Department of Electronics Technology, Guru Nanak Dev University, Amritsar 143005 (India); Pubby, Kunal, E-mail: kunalpubby02@gmail.com [Department of Electronics Technology, Guru Nanak Dev University, Amritsar 143005 (India)

    2017-01-15

    Strontium hexaferrites, doped with varying Co-Zr content (x) have been synthesized by sol-gel auto-combustion route using tartaric acid as fuel at 800 °C. X-ray diffraction and Fourier transform Infra-red have been carried out to confirm the phase formation, particle size (average 21.9–36.8 nm) and the bond formation respectively. Magnetic properties are scrutinized using vibrating sample magnetometer. Techniques like scanning electron microscopy, transmission electron microscopy and energy dispersive scattering have been employed to explore the surface morphology, particle size and composition of the nano-powders. Electromagnetic characterization of the prepared ferrites has been done using Vector Network Anlyzer in 12.4–18 GHz frequency range. The effect of calcination temperature (500–1000 °C) on the structure, morphology and magnetic properties has also been studied for x=0.2 and 800 °C has been found to be the most suitable temperature with the best magnetic properties. Increase in doping has resulted in resonance peaks in dielectric and magnetic loss spectra, leading to microwave absorption peaks. Ferrites with x=0.2, 0.8 and 1.0 have appropriate reflection loss less than −10 dB and bandwidth in Ku-band, hence can be used as effective absorbers in suppression of electromagnetic interference (EMI). The governance of impedance matching in deciding the absorption properties has been proved by using input impedance calculations. - Highlights: • Co-Zr doped strontium hexaferrite nanopowders have been prepared by sol-gel route. • 800 °C was most suitable temperaturewith best structural and magnetic properties. • Samples have M-type hexagonal structure with an average particle size of 36.47 nm. • Samples x=0.2, 0.8 and 1.0 are suitable for suppression of EM waves in Ku-band. • The origin of absorption peaks: impedance matching and losses has been explained.

  12. Behaviorism

    Science.gov (United States)

    Moore, J.

    2011-01-01

    Early forms of psychology assumed that mental life was the appropriate subject matter for psychology, and introspection was an appropriate method to engage that subject matter. In 1913, John B. Watson proposed an alternative: classical S-R behaviorism. According to Watson, behavior was a subject matter in its own right, to be studied by the…

  13. RNA interference of pheromone biosynthesis-activating neuropeptide receptor suppresses mating behavior by inhibiting sex pheromone production in Plutella xylostella (L.).

    Science.gov (United States)

    Lee, Dae-Weon; Shrestha, Sony; Kim, A Young; Park, Seok Joo; Yang, Chang Yeol; Kim, Yonggyun; Koh, Young Ho

    2011-04-01

    Sex pheromone production is regulated by pheromone biosynthesis-activating neuropeptide (PBAN) in many lepidopteran species. We cloned a PBAN receptor (Plx-PBANr) gene from the female pheromone gland of the diamondback moth, Plutella xylostella (L.). Plx-PBANr encodes 338 amino acids and has conserved structural motifs implicating in promoting G protein coupling and tyrosine-based sorting signaling along with seven transmembrane domains, indicating a typical G protein-coupled receptor. The expression of Plx-PBANr was found only in the pheromone gland of female adults among examined tissues and developmental stages. Heterologous expression in human uterus cervical cancer cells revealed that Plx-PBANr induced significant calcium elevation when challenged with Plx-PBAN. Female P. xylostella injected with double-stranded RNA specific to Plx-PBANr showed suppression of the receptor gene expression and exhibited significant reduction in pheromone biosynthesis, which resulted in loss of male attractiveness. Taken together, the identified PBAN receptor is functional in PBAN signaling via calcium secondary messenger, which leads to activation of pheromone biosynthesis and male attraction. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Dexamethasone suppression test

    Science.gov (United States)

    DST; ACTH suppression test; Cortisol suppression test ... During this test, you will receive dexamethasone. This is a strong man-made (synthetic) glucocorticoid medicine. Afterward, your blood is drawn ...

  15. Deconstructing continuous flash suppression

    OpenAIRE

    Yang, Eunice; Blake, Randolph

    2012-01-01

    In this paper, we asked to what extent the depth of interocular suppression engendered by continuous flash suppression (CFS) varies depending on spatiotemporal properties of the suppressed stimulus and CFS suppressor. An answer to this question could have implications for interpreting the results in which CFS influences the processing of different categories of stimuli to different extents. In a series of experiments, we measured the selectivity and depth of suppression (i.e., elevation in co...

  16. Deconstructing Interocular Suppression: Attention and Divisive Normalization.

    Directory of Open Access Journals (Sweden)

    Hsin-Hung Li

    2015-10-01

    Full Text Available In interocular suppression, a suprathreshold monocular target can be rendered invisible by a salient competitor stimulus presented in the other eye. Despite decades of research on interocular suppression and related phenomena (e.g., binocular rivalry, flash suppression, continuous flash suppression, the neural processing underlying interocular suppression is still unknown. We developed and tested a computational model of interocular suppression. The model included two processes that contributed to the strength of interocular suppression: divisive normalization and attentional modulation. According to the model, the salient competitor induced a stimulus-driven attentional modulation selective for the location and orientation of the competitor, thereby increasing the gain of neural responses to the competitor and reducing the gain of neural responses to the target. Additional suppression was induced by divisive normalization in the model, similar to other forms of visual masking. To test the model, we conducted psychophysics experiments in which both the size and the eye-of-origin of the competitor were manipulated. For small and medium competitors, behavioral performance was consonant with a change in the response gain of neurons that responded to the target. But large competitors induced a contrast-gain change, even when the competitor was split between the two eyes. The model correctly predicted these results and outperformed an alternative model in which the attentional modulation was eye specific. We conclude that both stimulus-driven attention (selective for location and feature and divisive normalization contribute to interocular suppression.

  17. Deconstructing Interocular Suppression: Attention and Divisive Normalization.

    Science.gov (United States)

    Li, Hsin-Hung; Carrasco, Marisa; Heeger, David J

    2015-10-01

    In interocular suppression, a suprathreshold monocular target can be rendered invisible by a salient competitor stimulus presented in the other eye. Despite decades of research on interocular suppression and related phenomena (e.g., binocular rivalry, flash suppression, continuous flash suppression), the neural processing underlying interocular suppression is still unknown. We developed and tested a computational model of interocular suppression. The model included two processes that contributed to the strength of interocular suppression: divisive normalization and attentional modulation. According to the model, the salient competitor induced a stimulus-driven attentional modulation selective for the location and orientation of the competitor, thereby increasing the gain of neural responses to the competitor and reducing the gain of neural responses to the target. Additional suppression was induced by divisive normalization in the model, similar to other forms of visual masking. To test the model, we conducted psychophysics experiments in which both the size and the eye-of-origin of the competitor were manipulated. For small and medium competitors, behavioral performance was consonant with a change in the response gain of neurons that responded to the target. But large competitors induced a contrast-gain change, even when the competitor was split between the two eyes. The model correctly predicted these results and outperformed an alternative model in which the attentional modulation was eye specific. We conclude that both stimulus-driven attention (selective for location and feature) and divisive normalization contribute to interocular suppression.

  18. Strangeness Suppression and Color Deconfinement

    Science.gov (United States)

    Satz, Helmut

    2018-02-01

    The relative multiplicities for hadron production in different high energy collisions are in general well described by an ideal gas of all hadronic resonances, except that under certain conditions, strange particle rates are systematically reduced. We show that the suppression factor γs, accounting for reduced strange particle rates in pp, pA and AA collisions at different collision energies, becomes a universal function when expressed in terms of the initial entropy density s0 or the initial temperature T of the produced thermal medium. It is found that γs increases from about 0.5 to 1.0 in a narrow temperature range around the quark-hadron transition temperature Tc ≃ 160 MeV. Strangeness suppression thus disappears with the onset of color deconfinement; subsequently, full equilibrium resonance gas behavior is attained.

  19. Deconstructing continuous flash suppression.

    Science.gov (United States)

    Yang, Eunice; Blake, Randolph

    2012-03-08

    In this paper, we asked to what extent the depth of interocular suppression engendered by continuous flash suppression (CFS) varies depending on spatiotemporal properties of the suppressed stimulus and CFS suppressor. An answer to this question could have implications for interpreting the results in which CFS influences the processing of different categories of stimuli to different extents. In a series of experiments, we measured the selectivity and depth of suppression (i.e., elevation in contrast detection thresholds) as a function of the visual features of the stimulus being suppressed and the stimulus evoking suppression, namely, the popular "Mondrian" CFS stimulus (N. Tsuchiya & C. Koch, 2005). First, we found that CFS differentially suppresses the spatial components of the suppressed stimulus: Observers' sensitivity for stimuli of relatively low spatial frequency or cardinally oriented features was more strongly impaired in comparison to high spatial frequency or obliquely oriented stimuli. Second, we discovered that this feature-selective bias primarily arises from the spatiotemporal structure of the CFS stimulus, particularly within information residing in the low spatial frequency range and within the smooth rather than abrupt luminance changes over time. These results imply that this CFS stimulus operates by selectively attenuating certain classes of low-level signals while leaving others to be potentially encoded during suppression. These findings underscore the importance of considering the contribution of low-level features in stimulus-driven effects that are reported under CFS.

  20. Sleep deprivation suppresses aggression in Drosophila

    Science.gov (United States)

    Kayser, Matthew S; Mainwaring, Benjamin; Yue, Zhifeng; Sehgal, Amita

    2015-01-01

    Sleep disturbances negatively impact numerous functions and have been linked to aggression and violence. However, a clear effect of sleep deprivation on aggressive behaviors remains unclear. We find that acute sleep deprivation profoundly suppresses aggressive behaviors in the fruit fly, while other social behaviors are unaffected. This suppression is recovered following post-deprivation sleep rebound, and occurs regardless of the approach to achieve sleep loss. Genetic and pharmacologic approaches suggest octopamine signaling transmits changes in aggression upon sleep deprivation, and reduced aggression places sleep-deprived flies at a competitive disadvantage for obtaining a reproductive partner. These findings demonstrate an interaction between two phylogenetically conserved behaviors, and suggest that previous sleep experiences strongly modulate aggression with consequences for reproductive fitness. DOI: http://dx.doi.org/10.7554/eLife.07643.001 PMID:26216041

  1. Suppressive competition: how sounds may cheat sight.

    Science.gov (United States)

    Kayser, Christoph; Remedios, Ryan

    2012-02-23

    In this issue of Neuron, Iurilli et al. (2012) demonstrate that auditory cortex activation directly engages local GABAergic circuits in V1 to induce sound-driven hyperpolarizations in layer 2/3 and layer 6 pyramidal neurons. Thereby, sounds can directly suppress V1 activity and visual driven behavior. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Sodium fire suppression

    Energy Technology Data Exchange (ETDEWEB)

    Malet, J C [DSN/SESTR, Centre de Cadarache, Saint-Paul-lez-Durance (France)

    1979-03-01

    Ignition and combustion studies have provided valuable data and guidelines for sodium fire suppression research. The primary necessity is to isolate the oxidant from the fuel, rather than to attempt to cool the sodium below its ignition temperature. Work along these lines has led to the development of smothering tank systems and a dry extinguishing powder. Based on the results obtained, the implementation of these techniques is discussed with regard to sodium fire suppression in the Super-Phenix reactor. (author)

  3. Sodium fire suppression

    International Nuclear Information System (INIS)

    Malet, J.C.

    1979-01-01

    Ignition and combustion studies have provided valuable data and guidelines for sodium fire suppression research. The primary necessity is to isolate the oxidant from the fuel, rather than to attempt to cool the sodium below its ignition temperature. Work along these lines has led to the development of smothering tank systems and a dry extinguishing powder. Based on the results obtained, the implementation of these techniques is discussed with regard to sodium fire suppression in the Super-Phenix reactor. (author)

  4. Pressure suppression device

    International Nuclear Information System (INIS)

    Mizumachi, Wataru; Fukuda, Akira; Kitaguchi, Hidemi; Shimizu, Toshiaki.

    1976-01-01

    Object: To relieve and absorb impact wave vibrations caused by steam and non-condensed gases releasing into the pressure suppression chamber at the time of an accident. Structure: The reactor container is filled with inert gases. A safety valve attached main steam pipe is provided to permit the excessive steam to escape, the valve being communicated with the pressure suppression chamber through an exhaust pipe. In the pressure suppression chamber, a doughnut-like cylindrical outer wall is filled at its bottom with pool water to condense the high temperature vapor released through the exhaust pipe. A head portion of a vent tube which leads the exhaust pipe is positioned at the top, and a down comer and an exhaust vent tube are locked by means of steady rests. At the bottom is mounted a pressure adsorber device which adsorbs a pressure from the pool water. (Kamimura, M.)

  5. Thyroxin hormone suppression treatment

    International Nuclear Information System (INIS)

    Samuel, A.M.

    1999-01-01

    One of the important modalities of treatment of thyroid cancer (TC) after surgery is the administration of thyroxin as an adjuvant treatment. The analysis supports the theory that thyroid suppression plays an important role in patient management. 300 μg of thyroxin, as this is an adequate dose for suppression is given. Ideally the dose should be tailored by testing s-TSH levels. However, since a large number of the patients come from out station cities and villages this is impractical. We therefore depend on clinical criteria of hyperthyroid symptoms and adjust the dose. Very few patients need such adjustment

  6. Pressure suppressing device

    International Nuclear Information System (INIS)

    Naito, Makoto.

    1980-01-01

    Purpose: To prevent the pressure in the reactor container from excessively increasing even when vapor leaks from the dry well to a space of the suppression chamber, without passing though the suppression pool at the time of loss of coolant accident. Constitution: When vapor of a high temperature and a high pressure at the time of loss of coolant accident flows from the dry well to the suppression chamber without passing through suppression pool water, vapor dose not condense with pool water, and therefore the pressure within the chamber abnormally increases. For this reason, this abnormal pressure is detected by a pressure detector thereby to start the operations of a blower and a pump. By starting the blower, the pressure in the dry well becomes lower than the pressure in the chamber, and vapor entirely passes through the pool water and entirely condenses with the pool water. By starting the pump, the pool water is sprayed over the space of the chamber, and vapor in the space is condensed. (Yoshino, Y.)

  7. Suppressive mechanisms in visual motion processing: From perception to intelligence.

    Science.gov (United States)

    Tadin, Duje

    2015-10-01

    Perception operates on an immense amount of incoming information that greatly exceeds the brain's processing capacity. Because of this fundamental limitation, the ability to suppress irrelevant information is a key determinant of perceptual efficiency. Here, I will review a series of studies investigating suppressive mechanisms in visual motion processing, namely perceptual suppression of large, background-like motions. These spatial suppression mechanisms are adaptive, operating only when sensory inputs are sufficiently robust to guarantee visibility. Converging correlational and causal evidence links these behavioral results with inhibitory center-surround mechanisms, namely those in cortical area MT. Spatial suppression is abnormally weak in several special populations, including the elderly and individuals with schizophrenia-a deficit that is evidenced by better-than-normal direction discriminations of large moving stimuli. Theoretical work shows that this abnormal weakening of spatial suppression should result in motion segregation deficits, but direct behavioral support of this hypothesis is lacking. Finally, I will argue that the ability to suppress information is a fundamental neural process that applies not only to perception but also to cognition in general. Supporting this argument, I will discuss recent research that shows individual differences in spatial suppression of motion signals strongly predict individual variations in IQ scores. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. J/Ψ suppression

    International Nuclear Information System (INIS)

    Giubellino, P.; Abreu, M.C.; Alessandro, B.; Alexa, C.; Arnaldi, R.; Astruc, J.; Atayan, M.; Baglin, C.; Baldit, A.; Bedjidian, M.; Bellaiche, F.; Beole, S.; Boldea, V.; Bordalo, P.; Bussiere, A.; Capony, V.; Casagrande, L.; Castor, J.; Chambon, T.; Chaurand, B.; Chevrot, I.; Cheynis, B.; Chiavassa, E.; Cicalo, C.; Comets, M.P.; Constantinescu, S.; Cruz, J.; De Falco, A.; De Marco, N.; Dellacasa, G.; Devaux, A.; Dita, S.; Drapier, O.; Espagnon, B.; Fargeix, J.; Filippov, S.N.; Fleuret, F.; Force, P.; Gallio, M.; Gavrilov, Y.K.; Gerschel, C.; Giubellino, P.; Golubeva, M.B.; Gonin, M.; Grigorian, A.A.; Grossiord, J.Y.; Guber, F.F.; Guichard, A.; Gulkaninan, H.; Hakobyan, R.; Haroutunian, R.; Idzik, M.; Jouan, D.; Karavitcheva, T.L.; Kluberg, L.; Kurepin, A.B.; Le Bornec, Y.; Lourenco, C.; Mac Cormick, M.; Macciotta, P.; Marzari-Chiesa, A.; Masera, M.; Masoni, A.; Mehrabyan, S.; Mourgues, S.; Musso, A.; Ohlsson-Malek, F.; Petiau, P.; Piccotti, A.; Pizzi, J.R.; Prado da Silva, W.L.; Puddu, G.; Quintans, C.; Racca, C.; Ramello, L.; Ramos, S.; Rato-Mendes, P.; Riccati, L.; Romana, A.; Sartori, S.; Saturnini, P.; Scomparin, E.; Serci, S.; Shahoyan, R.; Silva, S.; Soave, C.; Sonderegger, P.; Tarrago, X.; Temnikov, P.; Topilskaya, N.S.; Usai, G.; Vale, C.; Vercellin, E.; Willis, N.

    1999-01-01

    The cross section for J/Ψ production in Pb-Pb interactions at 158 GeV per nucleon is measured at the CERN SPS by the NA50 experiment. The final results from the 1995 run are presented here together with preliminary ones from the high-statistics 1996 run. An anomalous J/Ψ suppression is observed in Pb-Pb collisions as compared to extrapolations of the previous results obtained by the NA38 experiment with proton and lighter ion beams. The results of the two runs are in good agreement. The results from the 1996 run allow the study of the onset of the anomalous suppression within the same set of data, showing evidence of a sharp change of behaviour around a value of neutral transverse energy, as measured by our electromagnetic calorimeter, of about 50 GeV

  9. Suppress to feel and remember less: Neural correlates of explicit and implicit emotional suppression on perception and memory.

    Science.gov (United States)

    Katsumi, Yuta; Dolcos, Sanda

    2018-02-09

    Available evidence suggests that emotion regulation can modulate both immediate (emotional experience) and long-term (episodic memory) effects of emotion, and that both explicit and implicit forms may be effective. However, neural mechanisms by which explicit and implicit emotional suppression affect these phenomena remain unclear, particularly regarding their effects on memory. In this study, participants rated the emotional content of negative and neutral images, following explicit (verbal instructions) or implicit (priming) induction of emotional suppression goals, during functional magnetic resonance imaging. Participants' memory for the images was tested one week later. Behaviorally, explicit suppression reduced emotional ratings of negative images, whereas both explicit and implicit suppression reduced subsequent memory. At the neural level, the engagement of explicit suppression was uniquely associated with decreased activity in the amygdala (AMY), during emotional ratings, and in the AMY and inferior frontal gyrus (IFG), during successful encoding. Although both explicit and implicit suppression diminished functional connectivity between these regions and the hippocampus (HC) linked to successful encoding, explicit suppression was uniquely associated with interference with AMY-HC interactions, which no longer predicted subsequent memory for the explicitly-suppressed items. Overall, these findings advance our understanding of the common and dissociable mechanisms of explicit and implicit emotional suppression on perception and memory, and suggest their impact on both bottom-up and top-down mechanisms involved in emotion-cognition interactions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. The pressure suppression system

    International Nuclear Information System (INIS)

    Aust, E.

    1985-01-01

    Nuclear plants with boiling water reactors have a safety containment with a pressure suppression system (PSS). Proceeding on significant self-developments, today the three PSS-lines of General Electric Co. (GE), Kraftwerk Union AG (KWU) and ASEA-ATOM are predominant, which are currently represented by the MARK III type, the KWU type 72 and the BWR 75 containment. In addition, there are special developments for the nuclear ship propulsion and for the pressurized water reactors in the Soviet Union. Key design values of the PSS allow a first valuation of its loads during a hypothetical loss-of-coolant accident. (orig.) [de

  11. Expressive suppression and neural responsiveness to nonverbal affective cues.

    Science.gov (United States)

    Petrican, Raluca; Rosenbaum, R Shayna; Grady, Cheryl

    2015-10-01

    Optimal social functioning occasionally requires concealment of one's emotions in order to meet one's immediate goals and environmental demands. However, because emotions serve an important communicative function, their habitual suppression disrupts the flow of social exchanges and, thus, incurs significant interpersonal costs. Evidence is accruing that the disruption in social interactions, linked to habitual expressive suppression use, stems not only from intrapersonal, but also from interpersonal causes, since the suppressors' restricted affective displays reportedly inhibit their interlocutors' emotionally expressive behaviors. However, expressive suppression use is not known to lead to clinically significant social impairments. One explanation may be that over the lifespan, individuals who habitually suppress their emotions come to compensate for their interlocutors' restrained expressive behaviors by developing an increased sensitivity to nonverbal affective cues. To probe this issue, the present study used functional magnetic resonance imaging (fMRI) to scan healthy older women while they viewed silent videos of a male social target displaying nonverbal emotional behavior, together with a brief verbal description of the accompanying context, and then judged the target's affect. As predicted, perceivers who reported greater habitual use of expressive suppression showed increased neural processing of nonverbal affective cues. This effect appeared to be coordinated in a top-down manner via cognitive control. Greater neural processing of nonverbal cues among perceivers who habitually suppress their emotions was linked to increased ventral striatum activity, suggestive of increased reward value/personal relevance ascribed to emotionally expressive nonverbal behaviors. These findings thus provide neural evidence broadly consistent with the hypothesized link between habitual use of expressive suppression and compensatory development of increased responsiveness to

  12. Radiation effluent suppression system

    International Nuclear Information System (INIS)

    Watanabe, Atsushi.

    1992-01-01

    In a radiation release suppression system upon accident, an electromotive valve, a pneumatic operation valve or a manual operation valve is disposed to gas ventilation pipelines which are extended from both of a dry well and a wet well of a reactor container to a stuck. In addition, a combination filter of a metal fiber filter made of stainless steel etc. and an activated carbon fiber filter is disposed in the midway of pipelines in a reactor building. With such a constitution, the inside of the container can be depressurized (prevention of ruptures) and the amount of radioactive substances released to circumstances is remarkably suppressed by the effect of radioactive substance capturing effect of the metal fiber filter made of stainless steel etc. disposed in the vent pipe in the container and a radioactive substance capturing effect by the combination filter of the metal fiber filter made of stainless steel, etc. and the activated carbon fiber filter disposed in the gas ventilation pipelines even upon occurrence of an accident exceeding design basis. Systems can be simplified and minimized, and cost down can also be attained. (N.H.)

  13. Planck-suppressed operators

    International Nuclear Information System (INIS)

    Assassi, Valentin; Baumann, Daniel; Green, Daniel; McAllister, Liam

    2014-01-01

    We show that the recent Planck limits on primordial non-Gaussianity impose strong constraints on light hidden sector fields coupled to the inflaton via operators suppressed by a high mass scale Λ. We study a simple effective field theory in which a hidden sector field is coupled to a shift-symmetric inflaton via arbitrary operators up to dimension five. Self-interactions in the hidden sector lead to non-Gaussianity in the curvature perturbations. To be consistent with the Planck limit on local non-Gaussianity, the coupling to any hidden sector with light fields and natural cubic couplings must be suppressed by a very high scale Λ > 10 5 H. Even if the hidden sector has Gaussian correlations, nonlinearities in the mixing with the inflaton still lead to non-Gaussian curvature perturbations. In this case, the non-Gaussianity is of the equilateral or orthogonal type, and the Planck data requires Λ > 10 2 H

  14. Mothers' responses to children's negative emotions and child emotion regulation: the moderating role of vagal suppression.

    Science.gov (United States)

    Perry, Nicole B; Calkins, Susan D; Nelson, Jackie A; Leerkes, Esther M; Marcovitch, Stuart

    2012-07-01

    The current study examined the moderating effect of children's cardiac vagal suppression on the association between maternal socialization of negative emotions (supportive and nonsupportive responses) and children's emotion regulation behaviors. One hundred and ninety-seven 4-year-olds and their mothers participated. Mothers reported on their reactions to children's negative emotions and children's regulatory behaviors. Observed distraction, an adaptive self-regulatory strategy, and vagal suppression were assessed during a laboratory task designed to elicit frustration. Results indicated that children's vagal suppression moderated the association between mothers' nonsupportive emotion socialization and children's emotion regulation behaviors such that nonsupportive reactions to negative emotions predicted lower observed distraction and lower reported emotion regulation behaviors when children displayed lower levels of vagal suppression. No interaction was found between supportive maternal emotion socialization and vagal suppression for children's emotion regulation behaviors. Results suggest physiological regulation may serve as a buffer against nonsupportive emotion socialization. Copyright © 2011 Wiley Periodicals, Inc.

  15. Dynamic interactions of the cortical networks during thought suppression.

    Science.gov (United States)

    Aso, Toshihiko; Nishimura, Kazuo; Kiyonaka, Takashi; Aoki, Takaaki; Inagawa, Michiyo; Matsuhashi, Masao; Tobinaga, Yoshikazu; Fukuyama, Hidenao

    2016-08-01

    Thought suppression has spurred extensive research in clinical and preclinical fields, particularly with regard to the paradoxical aspects of this behavior. However, the involvement of the brain's inhibitory system in the dynamics underlying the continuous effort to suppress thoughts has yet to be clarified. This study aims to provide a unified perspective for the volitional suppression of internal events incorporating the current understanding of the brain's inhibitory system. Twenty healthy volunteers underwent functional magnetic resonance imaging while they performed thought suppression blocks alternating with visual imagery blocks. The whole dataset was decomposed by group-independent component analysis into 30 components. After discarding noise components, the 20 valid components were subjected to further analysis of their temporal properties including task-relatedness and between-component residual correlation. Combining a long task period and a data-driven approach, we observed a right-side-dominant, lateral frontoparietal network to be strongly suppression related. This network exhibited increased fluctuation during suppression, which is compatible with the well-known difficulty of suppression maintenance. Between-network correlation provided further insight into the coordinated engagement of the executive control and dorsal attention networks, as well as the reciprocal activation of imagery-related components, thus revealing neural substrates associated with the rivalry between intrusive thoughts and the suppression process.

  16. Modulation of TRP channels by resveratrol and other stilbenoids

    Directory of Open Access Journals (Sweden)

    Yu Lina

    2013-02-01

    Full Text Available Abstract Background Resveratrol (3,5,4’ - trihydroxy-trans-stilbene, a widely distributed natural stilbenoid, was proposed to account for the unique effects of red wine on life span and health. It has been reported to possess various biological and pharmacological activities, such as anti-oxidant, anti-inflammatory, and anti-carcinogenic effects. Here, using whole-cell patch-clamp techniques and behavioral analyses, we investigated whether resveratrol and other stilbenoids can modulate TRP channels in sensory neurons in vitro, and have analgesic effects in vivo. Results We found that resveratrol dose-dependently suppressed the allyl isothiocyanate (AITC-induced currents (IAITC in HEK293 cells that express TRPA1, as well as in rat dorsal root ganglion (DRG neurons. Instead, pinosylvin methyl ether (PME, another derivate of stilbene which has a similar structure to resveratrol, dose-dependently blocked the capsaicin-induced currents (ICAP in HEK293 cells that express TRPV1 as well as in DRG neurons. Interestingly, resveratrol had no inhibitory effect on the ICAP, and PME had no effect on the IAITC. Otherwise, trans-stilbene showed no any effect on IAITC or ICAP. The concentration response curve of AITC showed that resveratrol inhibited the action of TRPA1 not by changing the EC50, but by suppressing the AITC-induced maximum response. By contrast, the inhibition of TRPV1 by PME did not change the capsaicin-induced maximum response but did cause a right shift of the EC50. Moreover, pre-administration of resveratrol suppressed intraplantar injections of AITC-evoked nocifensive behaviors, as well as that PME suppressed capsaicin-evoked one. Conclusions These data suggest that resveratrol and other stilbenoids may have an inhibitory effect on TRP channels. In addition, these stilbenoids modulate TRP channel activity in different ways.

  17. Screening for suppression in young children: the Polaroid Suppression test

    NARCIS (Netherlands)

    Pott, J.W.R.; Oosterveen, DK; Van Hof-van Duin, J

    1998-01-01

    Background: Assessment of monocular visual impairment during screening of young children is often hampered by lack of cooperation. Because strabismus, amblyopia, or anisometropia may lead to monocular suppression during binocular viewing conditions, a test was developed to screen far suppression in

  18. Pressure suppression device

    International Nuclear Information System (INIS)

    Yoshida, Toyokazu.

    1976-01-01

    Purpose: To provide a pressure suppression device for a gas cooled reactor wherein the coolant is discharged in a reactor building by a loss-of-coolant accident or the like, the increase in the pressure and temperature is controlled and thermal energy of the discharged coolant of high temperature and high pressure can be absorbed. Constitution: A low heat source unit is provided at the upper part in an inner space of a reactor building provided around the reactor, and at the upper part of the low heat source unit a stirring fan for mixing gas within the building, and a low heat source circulating the low heat source through a pipe is connected to the low heat source unit. The low heat source unit is provided with the pipe arranged in a spiral shape at the upper part of the space of the unit, and a large number of fins are provided at the outer surface of the pipe for increasing the transmission area and improve the heat exchange. When the coolant of high temperature and high pressure has been lost in the building, the thermal energy of the coolant is absorbed by the low heat source unit. (Aizawa, K.)

  19. Compton suppression gamma ray spectrometry

    International Nuclear Information System (INIS)

    Landsberger, S.; Iskander, F.Y.; Niset, M.; Heydorn, K.

    2002-01-01

    In the past decade there have been many studies to use Compton suppression methods in routine neutron activation analysis as well as in the traditional role of low level gamma ray counting of environmental samples. On a separate path there have been many new PC based software packages that have been developed to enhance photopeak fitting. Although the newer PC based algorithms have had significant improvements, they still suffer from being effectively used in weak gamma ray lines in natural samples or in neutron activated samples that have very high Compton backgrounds. We have completed a series of experiments to show the usefulness of Compton suppression. As well we have shown the pitfalls when using Compton suppression methods for high counting deadtimes as in the case of neutron activated samples. We have also investigated if counting statistics are the same both suppressed and normal modes. Results are presented in four separate experiments. (author)

  20. Thyroid suppression test with dextrothyroxine

    International Nuclear Information System (INIS)

    Rosenthal, D.; Fridman, J.; Ribeiro, H.B.

    1978-01-01

    The classic thyroid suppression test with triiodothyronine (l-T 3 ) has been shown to be efficient as an auxiliary method in the diagnosis of thyroid diseases, but should not be performed on elderly patients or on those with heart disease or a tendency to tachycardia. Since these subjects seem able to support a short period of dextro-thyronine (d-T 4 ) feeding, we compared the effect of d-T 4 and l-T 3 on the 24 hours thyroid uptake in euthyroid and hyperthyroid subjects. After basal radio-iodine uptake determination, 99 patients without hyperthyroidism and 27 with Graves' disease were randomly divided in 2 groups; one received 100μg of l-T 3 per day and the other 4 mg of d-T 4 per day, both groups being treated for a period of 10 days. At the end of this suppression period the 24 hours radio-iodine uptake was measured again and the percentual suppression index (S.I.) calculated. Since the comparison of the two groups showed no difference between the suppressive effect of l-T 3 and d-T 4 in euthyroid subjects, while dextro-thyronine, as levo-triiodothyronine, did not suppress the 24 hours uptake of hyperthyroid patients, l-T 3 or d-T 4 can be used interchangeably to test thyroid suppressibility. In the euthyroid subjects the normal range for the post-suppression uptake was 0-17.1% and for the suppression index 54,7.100% [pt

  1. Suppressed Charmed B Decay

    Energy Technology Data Exchange (ETDEWEB)

    Snoek, Hella Leonie [Vrije Univ., Amsterdam (Netherlands)

    2009-06-02

    This thesis describes the measurement of the branching fractions of the suppressed charmed B0 → D*- a0+ decays and the non-resonant B0 → D*- ηπ+ decays in approximately 230 million Υ(4S) → B$\\bar{B}$ events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B0 → D*- a{sub 0}+ decays show large QCD model dependent uncertainties. Non-factorizing terms, in the naive factorization model, that can be calculated by QCD factorizing models have a large impact on the branching fraction of these decay modes. The predictions of the branching fractions are of the order of 10-6. The measurement of the branching fraction gives more insight into the theoretical models. In general a better understanding of QCD models will be necessary to conduct weak interaction physics at the next level. The presence of CP violation in electroweak interactions allows the differentiation between matter and antimatter in the laws of physics. In the Standard Model, CP violation is incorporated in the CKM matrix that describes the weak interaction between quarks. Relations amongst the CKM matrix elements are used to present the two relevant parameters as the apex of a triangle (Unitarity Triangle) in a complex plane. The over-constraining of the CKM triangle by experimental measurements is an important test of the Standard Model. At this moment no stringent direct measurements of the CKM angle γ, one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle γ can be performed using the decays of neutral B mesons. The B0 → D*- a0+ decay is sensitive to the angle γ and, in comparison to the current decays that are being employed, could significantly

  2. Resource allocation for wildland fire suppression planning using a stochastic program

    Science.gov (United States)

    Alex Taylor Masarie

    2011-01-01

    Resource allocation for wildland fire suppression problems, referred to here as Fire-S problems, have been studied for over a century. Not only have the many variants of the base Fire-S problem made it such a durable one to study, but advances in suppression technology and our ever-expanding knowledge of and experience with wildland fire behavior have required almost...

  3. Memory suppression is an active process that improves over childhood

    Directory of Open Access Journals (Sweden)

    Pedro M Paz-Alonso

    2009-09-01

    Full Text Available We all have memories that we prefer not to think about. The ability to suppress retrieval of unwanted memories has been documented in behavioral and neuroimaging research using the Think/No-Think (TNT paradigm with adults. Attempts to stop memory retrieval are associated with increased activation of lateral prefrontal cortex (PFC and concomitant reduced activation in medial temporal lobe (MTL structures. However, the extent to which children have the ability to actively suppress their memories is unknown. This study investigated memory suppression in middle childhood using the TNT paradigm. Forty children aged 8 to 12 and 30 young adults were instructed either to remember (Think or suppress (No-Think the memory of the second word of previously studied word-pairs, when presented with the first member as a reminder. They then performed two different cued recall tasks, testing their memory for the second word in each pair after the Think/No-Think phase using the same first studied word within the pair as a cue (intra-list cue and also an independent cue (extra-list cue. Children exhibited age-related improvements in memory suppression from age 8 to 12 in both memory tests, against a backdrop of overall improvements in declarative memory over this age range. These findings suggest that memory suppression is an active process that develops during late childhood, likely due to an age-related refinement in the ability to engage PFC to down-regulate activity in areas involved in episodic retrieval.

  4. Dopamine agonist suppression of rapid-eye-movement sleep is secondary to sleep suppression mediated via limbic structures

    International Nuclear Information System (INIS)

    Miletich, R.S.

    1985-01-01

    The effects of pergolide, a direct dopamine receptor agonist, on sleep and wakefulness, motor behavior and 3 H-spiperone specific binding in limbic structures and striatum in rats was studied. The results show that pergolide induced a biphasic dose effect, with high doses increasing wakefulness and suppressing sleep while low dose decreased wakefulness, but increased sleep. It was shown that pergolide-induced sleep suppression was blocked by α-glupenthixol and pimozide, two dopamine receptor antagonists. It was further shown that pergolide merely delayed the rebound resulting from rapid-eye-movement (REM) sleep deprivation, that dopamine receptors stimulation had no direct effect on the period, phase or amplitude of the circadian rhythm of REM sleep propensity and that there was no alteration in the coupling of REM sleep episodes with S 2 episodes. Rapid-eye-movement sleep deprivation resulted in increased sensitivity to the pergolide-induced wakefulness stimulation and sleep suppression and pergolide-induced motor behaviors of locomotion and head bobbing. 3 H-spiperone specific binding to dopamine receptors was shown to be altered by REM sleep deprivation in the subcortical limbic structures. It is concluded that the REM sleep suppressing action of dopamine receptor stimulation is secondary to sleep suppression per se and not secondary to a unique effect on the REM sleep. Further, it is suggested that the wakefulness stimulating action of dopamine receptor agonists is mediated by activation of the dopamine receptors in the terminal areas of the mesolimbocortical dopamine projection system

  5. Beyond viral suppression of HIV

    DEFF Research Database (Denmark)

    Lazarus, Jeffrey V.; Safreed-Harmon, Kelly; Barton, Simon E

    2016-01-01

    BACKGROUND: In 2016, the World Health Organization (WHO) adopted a new Global Health Sector Strategy on HIV for 2016-2021. It establishes 15 ambitious targets, including the '90-90-90' target calling on health systems to reduce under-diagnosis of HIV, treat a greater number of those diagnosed......, and ensure that those being treated achieve viral suppression. DISCUSSION: The WHO strategy calls for person-centered chronic care for people living with HIV (PLHIV), implicitly acknowledging that viral suppression is not the ultimate goal of treatment. However, it stops short of providing an explicit target...... for health-related quality of life. It thus fails to take into account the needs of PLHIV who have achieved viral suppression but still must contend with other intense challenges such as serious non-communicable diseases, depression, anxiety, financial stress, and experiences of or apprehension about HIV...

  6. Aging and repeated thought suppression success.

    Directory of Open Access Journals (Sweden)

    Ann E Lambert

    Full Text Available Intrusive thoughts and attempts to suppress them are common, but while suppression may be effective in the short-term, it can increase thought recurrence in the long-term. Because intentional suppression involves controlled processing, and many aspects of controlled processing decline with age, age differences in thought suppression outcomes may emerge, especially over repeated thought suppression attempts as cognitive resources are expended. Using multilevel modeling, we examined age differences in reactions to thought suppression attempts across four thought suppression sequences in 40 older and 42 younger adults. As expected, age differences were more prevalent during suppression than during free monitoring periods, with younger adults indicating longer, more frequent thought recurrences and greater suppression difficulty. Further, younger adults' thought suppression outcomes changed over time, while trajectories for older adults' were relatively stable. Results are discussed in terms of older adults' reduced thought recurrence, which was potentially afforded by age-related changes in reactive control and distractibility.

  7. Accentuation-suppression and scaling

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik; Bundesen, Claus

    2012-01-01

    The limitations of the visual short-term memory (VSTM) system have become an increasingly popular field of study. One line of inquiry has focused on the way attention selects objects for encoding into VSTM. Using the framework of the Theory of Visual Attention (TVA; Bundesen, 1990 Psychological...... a scaling mechanism modulating the decision bias of the observer and also through an accentuation-suppression mechanism that modulates the degree of subjective relevance of objects, contracting attention around fewer, highly relevant objects while suppressing less relevant objects. These mechanisms may...

  8. Suppressive and immunoprotective functions of Tregs

    Directory of Open Access Journals (Sweden)

    Pushpa ePandiyan

    2011-11-01

    Full Text Available CD4+CD25+Foxp3+ T lymphocytes, known as regulatory T cells or Tregs, have been proposed to be a lineage of professional immune suppressive cells that exclusively counteract the effects of the immunoprotective "helper" and "cytotoxic" lineages of T lymphocytes. Here we discuss new concepts on the mechanisms and functions of Tregs. There are several key points we emphasize: 1. Tregs exert suppressive effects both directly on effector T cells and indirectly through antigen-presenting cells (APCs; 2. Regulation can occur through a novel mechanism of cytokine consumption to regulate as opposed to the usual mechanism of cytokine/chemokine production; 3. In cases where CD4+ effector T cells are directly inhibited by Tregs, it is chiefly through a mechanism of lymphokine withdrawal apoptosis leading to polyclonal deletion (PCD; and 4. Contrary to the current view, we discuss new evidence that Tregs, similar to other T cells lineages, can promote protective immune responses in certain infectious contexts (Pandiyan et al. 2011; Chen et al 2011. Although these points are at variance to varying degrees with the standard model of Treg behavior, we will recount developing findings that support these new concepts.

  9. Suppression of beam-excited electron waves by an externally applied RF signal

    International Nuclear Information System (INIS)

    Fukumasa, Osamu; Itatani, Ryohei

    1980-11-01

    Suppression of the beam-excited electron wave in a bounded system is investigated in connection with the beam distribution function. Wave suppression has two different processes depending on whether injected beams are reflected at the other end or not. In the absence of reflected beam electrons, deformation of the beam distribution function is observed in relation to the suppression of the electron wave. However, when beam electrons are reflected, the external wave suppresses the electron wave but distribution function shows no appreciable change. These experimental results show that nonlinear behaviors of beam electrons, namely behaviors of reflected beams, are quite important for wave suppression. By using the method of partial simulation, interaction between two waves in the bounded system including nonlinear motions of beam electrons is studied numerically. Qualitative agreement between experimental and numerical results is obtained. (author)

  10. Learning to ignore: acquisition of sustained attentional suppression.

    Science.gov (United States)

    Dixon, Matthew L; Ruppel, Justin; Pratt, Jay; De Rosa, Eve

    2009-04-01

    We examined whether the selection mechanisms committed to the suppression of ignored stimuli can be modified by experience to produce a sustained, rather than transient, change in behavior. Subjects repeatedly ignored the shape of stimuli, while attending to their color. On subsequent attention to shape, there was a robust and sustained decrement in performance that was selective to when shape was ignored across multiple-color-target contexts, relative to a single-color-target context. Thus, amount of time ignored was not sufficient to induce a sustained performance decrement. Moreover, in this group, individual differences in initial color target selection were associated with the subsequent performance decrement when attending to previously ignored stimuli. Accompanying this sustained decrement in performance was a transfer in the locus of suppression from an exemplar (e.g., a circle) to a feature (i.e., shape) level of representation. These data suggest that learning can influence attentional selection by sustained attentional suppression of ignored stimuli.

  11. Long-term health benefits of appetite suppressants remain unproven

    Directory of Open Access Journals (Sweden)

    Francisco José Roma Paumgartten

    2011-12-01

    Full Text Available Because of the increasing prevalence of obesity, prevention and treatment of overweight has become a major public health concern. In addition to diet and exercise, drugs are needed for patients who failed to lose weight with behavioral treatment. The current article aimed to summarize recent concerns on the safety and efficacy of appetite suppressants. Several appetite suppressants have been banned for safety reasons. In 2010, sibutramine was withdrawn from the market because a long-term study showed it increased the risks of cardiovascular events. So far no study with a sufficiently large sample size has demonstrated that appetite suppressants can reduce morbidity and mortality associated with overweight. The withdrawal of sibutramine highlights that guidelines for the evaluation of weight control drugs must be more stringent, and studies on their long-term health benefits are needed prior to their marketing.

  12. Sexual Behaviors in Autism: Problems of Definition and Management.

    Science.gov (United States)

    Realmuto, George M.; Ruble, Lisa A.

    1999-01-01

    Explores the problems of definition of sexual behaviors in individuals with autism and describes a case that highlights the difficulties of management. After failure of behavioral and educational programs, a testosterone-suppressing medication was used resulting in suppression of public masturbation behaviors and retention of the participant's…

  13. Formation and suppression of acoustic memories during human sleep.

    Science.gov (United States)

    Andrillon, Thomas; Pressnitzer, Daniel; Léger, Damien; Kouider, Sid

    2017-08-08

    Sleep and memory are deeply related, but the nature of the neuroplastic processes induced by sleep remains unclear. Here, we report that memory traces can be both formed or suppressed during sleep, depending on sleep phase. We played samples of acoustic noise to sleeping human listeners. Repeated exposure to a novel noise during Rapid Eye Movements (REM) or light non-REM (NREM) sleep leads to improvements in behavioral performance upon awakening. Strikingly, the same exposure during deep NREM sleep leads to impaired performance upon awakening. Electroencephalographic markers of learning extracted during sleep confirm a dissociation between sleep facilitating memory formation (light NREM and REM sleep) and sleep suppressing learning (deep NREM sleep). We can trace these neural changes back to transient sleep events, such as spindles for memory facilitation and slow waves for suppression. Thus, highly selective memory processes are active during human sleep, with intertwined episodes of facilitative and suppressive plasticity.Though memory and sleep are related, it is still unclear whether new memories can be formed during sleep. Here, authors show that people could learn new sounds during REM or light non-REM sleep, but that learning was suppressed when sounds were played during deep NREM sleep.

  14. Frozen with fear: Conditioned suppression in a virtual reality model of human anxiety.

    Science.gov (United States)

    Allcoat, Devon; Greville, W James; Newton, Philip M; Dymond, Simon

    2015-09-01

    Freezing-like topographies of behavior are elicited in conditioned suppression tasks whereby appetitive behavior is reduced by presentations of an aversively conditioned threat cue relative to a safety cue. Conditioned suppression of operant behavior by a Pavlovian threat cue is an established laboratory model of quantifying the response impairment seen in anxiety disorders. Little is known however about how different response topographies indicative of conditioned suppression are elicited in humans. Here, we refined a novel virtual reality (VR) paradigm in which presentations of a threat cue of unpredictable duration occurred while participants performed an operant response of shooting and destroying boxes searching for hidden gold. The VR paradigm detected significant suppression of response topographies (shots, hits and breaks) for a Pavlovian threat cue relative to a safety cue and novel cue presentations. Implications of the present findings for translational research on appetitive and aversive conflict in anxiety disorders are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Distinguishing among potential mechanisms of singleton suppression.

    Science.gov (United States)

    Gaspelin, Nicholas; Luck, Steven J

    2018-04-01

    Previous research has revealed that people can suppress salient stimuli that might otherwise capture visual attention. The present study tests between 3 possible mechanisms of visual suppression. According to first-order feature suppression models , items are suppressed on the basis of simple feature values. According to second-order feature suppression models , items are suppressed on the basis of local discontinuities within a given feature dimension. According to global-salience suppression models , items are suppressed on the basis of their dimension-independent salience levels. The current study distinguished among these models by varying the predictability of the singleton color value. If items are suppressed by virtue of salience alone, then it should not matter whether the singleton color is predictable. However, evidence from probe processing and eye movements indicated that suppression is possible only when the color values are predictable. Moreover, the ability to suppress salient items developed gradually as participants gained experience with the feature that defined the salient distractor. These results are consistent with first-order feature suppression models, and are inconsistent with the other models of suppression. In other words, people primarily suppress salient distractors on the basis of their simple features and not on the basis of salience per se. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  16. Non-disruptive tactics of suppression are superior in countering terrorism, insurgency, and financial panics.

    Science.gov (United States)

    Siegel, David A

    2011-04-13

    Suppressing damaging aggregate behaviors such as insurgency, terrorism, and financial panics are important tasks of the state. Each outcome of these aggregate behaviors is an emergent property of a system in which each individual's action depends on a subset of others' actions, given by each individual's network of interactions. Yet there are few explicit comparisons of strategies for suppression, and none that fully incorporate the interdependence of individual behavior. Here I show that suppression tactics that do not require the removal of individuals from networks of interactions are nearly always more effective than those that do. I find using simulation analysis of a general model of interdependent behavior that the degree to which such less disruptive suppression tactics are superior to more disruptive ones increases in the propensity of individuals to engage in the behavior in question. Thus, hearts-and-minds approaches are generally more effective than force in counterterrorism and counterinsurgency, and partial insurance is usually a better tactic than gag rules in quelling financial panics. Differences between suppression tactics are greater when individual incentives to support terrorist or insurgent groups, or susceptibilities to financial panic, are higher. These conclusions have utility for policy-makers seeking to end bloody conflicts and prevent financial panics. As the model also applies to mass protest, its conclusions provide insight as well into the likely effects of different suppression strategies undertaken by authoritarian regimes seeking to hold on to power in the face of mass movements seeking to end them.

  17. Consequences of stereotype suppression and internal suppression motivation : A self-regulation approach

    NARCIS (Netherlands)

    Gordijn, Ernestine H; Hindriks, Inge; Koomen, W; Dijksterhuis, Ap; van Knipppenberg, A.

    The present research studied the effects of suppression of stereotypes on subsequent stereotyping. Moreover, the moderating influence of motivation to suppress stereotypes was examined. The first three experiments showed that suppression of stereotypes leads to the experience of engaging in

  18. Burst suppression in sleep in a routine outpatient EEG

    Directory of Open Access Journals (Sweden)

    Ammar Kheder

    2014-01-01

    Full Text Available Burst suppression (BS is an electroencephalogram (EEG pattern that is characterized by brief bursts of spikes, sharp waves, or slow waves of relatively high amplitude alternating with periods of relatively flat EEG or isoelectric periods. The pattern is usually associated with coma, severe encephalopathy of various etiologies, or general anesthesia. We describe an unusual case of anoxic brain injury in which a BS pattern was seen during behaviorally defined sleep during a routine outpatient EEG study.

  19. Burst suppression in sleep in a routine outpatient EEG ?

    OpenAIRE

    Kheder, Ammar; Bianchi, Matt T.; Westover, M. Brandon

    2014-01-01

    Burst suppression (BS) is an electroencephalogram (EEG) pattern that is characterized by brief bursts of spikes, sharp waves, or slow waves of relatively high amplitude alternating with periods of relatively flat EEG or isoelectric periods. The pattern is usually associated with coma, severe encephalopathy of various etiologies, or general anesthesia. We describe an unusual case of anoxic brain injury in which a BS pattern was seen during behaviorally defined sleep during a routine outpatient...

  20. MRI correlates of interaction between gender and expressive suppression among the Chinese population.

    Science.gov (United States)

    Wang, Kangcheng; Huang, Hui; Chen, Li; Hou, Xin; Zhang, Yong; Yang, Junyi; Hao, Xin; Qiu, Jiang

    2017-04-07

    Expressive suppression is a kind of emotion regulation strategies by suppressing behaviors related to emotional responding. Despite the amount of behavioral research on expressive suppression, the structural and functional mechanisms underlying the interaction between gender and expressive suppression in Chinese healthy subjects have remained unknown. In the current study, we assessed the levels of expressive suppression and acquired the structural and functional imaging data from 273 Chinese individuals. A nearly automatic cortical processing technique was used to calculate cortical thickness for each subject. The results from cortical thickness analyses revealed a significant interaction between gender and expressive suppression in the superior frontal gyrus. Then, we conducted the whole-brain functional connectivity analysis with the seed of the superior frontal gyrus to explore the functionally related regions of brain. Subsequent analysis of the interaction between gender and expressive suppression indicated a significant functional connectivity between the superior frontal gyrus and default mode network (DMN) core regions, including the medial prefrontal cortex, precuneus and parahippocampal gyrus. Our results provided the robust empirical evidence illustrating the role of the superior frontal gyrus and DMN in gender difference of expressive suppression among the Chinese population. These findings might have implications for understanding gender difference in emotion processing and regulation. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  1. The consequences of suppressing affective displays in romantic relationships: A challenge and threat perspective.

    Science.gov (United States)

    Peters, Brett J; Jamieson, Jeremy P

    2016-10-01

    Emotion suppression is one of the most studied topics in emotion regulation. However, little is known about how response-focused regulation strategies unfold in romantic relationships from the perspectives of both emotion regulators and their interaction partners. Using the biopsychosocial (BPS) model of challenge and threat as an organizing framework, 2 experiments examined effects of expressive suppression (vs. expression) on affective, cognitive, physiological, and behavioral processes in regulators and their romantic partners. In Experiment 1 a crowd-sourced sample of individuals currently in a romantic relationship simulated scenarios in which the self or partner engaged in response-focused emotion regulation (expression or suppression of affective displays). Suppressors expected worse outcomes compared with expressers. However, individuals on the receiving end of suppression (suppression targets) did not differ from expression targets. Experiment 2 then examined romantic couples' responses to suppression/expression in vivo. Regulators were randomly assigned to suppress/express affective displays and partners (targets) were unaware of the manipulation. Suppressors and suppression targets exhibited more malignant physiological responses (increased vascular resistance and elevated cortisol reactivity) during an emotional conversation and reduced intimacy behavior as measured with a novel touch task. Consequences for relationship processes are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  2. Suppression of stratified explosive interactions

    Energy Technology Data Exchange (ETDEWEB)

    Meeks, M.K.; Shamoun, B.I.; Bonazza, R.; Corradini, M.L. [Wisconsin Univ., Madison, WI (United States). Dept. of Nuclear Engineering and Engineering Physics

    1998-01-01

    Stratified Fuel-Coolant Interaction (FCI) experiments with Refrigerant-134a and water were performed in a large-scale system. Air was uniformly injected into the coolant pool to establish a pre-existing void which could suppress the explosion. Two competing effects due to the variation of the air flow rate seem to influence the intensity of the explosion in this geometrical configuration. At low flow rates, although the injected air increases the void fraction, the concurrent agitation and mixing increases the intensity of the interaction. At higher flow rates, the increase in void fraction tends to attenuate the propagated pressure wave generated by the explosion. Experimental results show a complete suppression of the vapor explosion at high rates of air injection, corresponding to an average void fraction of larger than 30%. (author)

  3. Chk1 suppressed cell death

    Directory of Open Access Journals (Sweden)

    Meuth Mark

    2010-09-01

    Full Text Available Abstract The role of Chk1 in the cellular response to DNA replication stress is well established. However recent work indicates a novel role for Chk1 in the suppression of apoptosis following the disruption of DNA replication or DNA damage. This review will consider these findings in the context of known pathways of Chk1 signalling and potential applications of therapies that target Chk1.

  4. In-Flight Suppressant Deployment Temperatures

    National Research Council Canada - National Science Library

    Bein, Donald

    2006-01-01

    .... An assessment is made of the model output versus some aircraft measurement data, fire suppressant boiling point criterion, as well as the history of altitude/temperature at which fire suppressants have been deployed...

  5. Presence of pups suppresses hunger-induced feeding in virgin adult mice of both sexes.

    Science.gov (United States)

    Han, Ying; Li, Xing-Yu; Wang, Shao-Ran; Wei, Yi-Chao; Xu, Xiao-Hong

    2017-10-24

    Despite recent progress on neural pathways underlying individual behaviors, how an animal balances and prioritizes behavioral outputs remains poorly understood. While studying the relationship between hunger-induced feeding and pup-induced maternal behaviors in virgin female mice, we made the unexpected discovery that presence of pups strongly delayed and decreased food consumption. Strikingly, presence of pups also suppressed feeding induced by optogenetic activation of Agrp neurons. Such a suppressive effect inversely correlated with the extents of maternal behaviors, but did not rely on the display of these behaviors, and was also present in virgin males. Furthermore, chemogenetic activation of Vglut2+ neurons in the medial preoptic area (mPOA), a region critical for maternal behaviors and motivation, was sufficient to suppress hunger-induced feeding. However, muscimol inhibition of the mPOA, while disrupting maternal behaviors, did not prevent pup suppression of feeding, indicating that neural pathways in other brain regions may also mediate such an effect. Together, these results provide novel insights into neural coordination of pup care and feeding in mice and organizations of animal behaviors in general. Copyright © 2017. Published by Elsevier Ltd.

  6. In the suppression of regge cut contributions

    International Nuclear Information System (INIS)

    Chia, S.P.

    1975-07-01

    It is shown that contributions of reggeon-pomeron cuts are suppressed in amplitudes with opposite natural to the reggeon. This suppression grows logarithmically with energy. The suppression in the πP cut is, however, found to be weak. Consequence on conspiracy is discussed

  7. Factor structure and clinical correlates of the Food Thought Suppression Inventory within treatment seeking obese women with binge eating disorder

    Science.gov (United States)

    Barnes, Rachel D.; Sawaoka, Takuya; White, Marney A.; Masheb, Robin M.; Grilo, Carlos M.

    2013-01-01

    Prior research on the relations among eating behaviors and thought suppression is limited to a measure of general thought suppression, the White Bear Suppression Inventory. To address this limitation, researchers recently validated the Food Thought Suppression Inventory (FTSI). Analyses using this measure suggest that food thought suppression is distinct from and is more predictive of eating disorder psychopathology than is general thought suppression. The FTSI, however, has not yet been validated in clinical samples. The purpose of the current study is to examine the factor structure and clinical correlates of the FTSI within treatment seeking obese women with binge eating disorder (BED; N = 128). Analyses revealed a valid and reliable one-factor measure of food thought suppression that was related to higher levels of eating and general psychopathology. The findings provide evidence for the use of the FTSI with obese women with BED. Future research should examine the psychometric properties of the FTSI within larger and more diverse samples. PMID:23265399

  8. Chaotic Dynamics in Smart Grid and Suppression Scheme via Generalized Fuzzy Hyperbolic Model

    Directory of Open Access Journals (Sweden)

    Qiuye Sun

    2014-01-01

    Full Text Available This paper presents a method to control chaotic behavior of a typical Smart Grid based on generalized fuzzy hyperbolic model (GFHM. As more and more distributed generations (DG are incorporated into the Smart Grid, the chaotic behavior occurs increasingly. To verify the behavior, a dynamic model which describes a power system with DG is presented firstly. Then, the simulation result shows that the power system can lead to chaos under certain initial conditions. Based on the universal approximation of GFHM, we confirm that the chaotic behavior could be suppressed by a new controller, which is designed by means of solving a linear matrix inequality (LMI. This approach could make a good application to suppress the chaos in Smart Grid. Finally, a numerical example is given to demonstrate the effectiveness of the proposed chaotic suppression strategy.

  9. Dopamine agonist suppression of rapid-eye-movement sleep is secondary to sleep suppression mediated via limbic structures

    Energy Technology Data Exchange (ETDEWEB)

    Miletich, R.S.

    1985-01-01

    The effects of pergolide, a direct dopamine receptor agonist, on sleep and wakefulness, motor behavior and /sup 3/H-spiperone specific binding in limbic structures and striatum in rats was studied. The results show that pergolide induced a biphasic dose effect, with high doses increasing wakefulness and suppressing sleep while low dose decreased wakefulness, but increased sleep. It was shown that pergolide-induced sleep suppression was blocked by ..cap alpha..-glupenthixol and pimozide, two dopamine receptor antagonists. It was further shown that pergolide merely delayed the rebound resulting from rapid-eye-movement (REM) sleep deprivation, that dopamine receptors stimulation had no direct effect on the period, phase or amplitude of the circadian rhythm of REM sleep propensity and that there was no alteration in the coupling of REM sleep episodes with S/sub 2/ episodes. Rapid-eye-movement sleep deprivation resulted in increased sensitivity to the pergolide-induced wakefulness stimulation and sleep suppression and pergolide-induced motor behaviors of locomotion and head bobbing. /sup 3/H-spiperone specific binding to dopamine receptors was shown to be altered by REM sleep deprivation in the subcortical limbic structures. It is concluded that the REM sleep suppressing action of dopamine receptor stimulation is secondary to sleep suppression per se and not secondary to a unique effect on the REM sleep. Further, it is suggested that the wakefulness stimulating action of dopamine receptor agonists is mediated by activation of the dopamine receptors in the terminal areas of the mesolimbocortical dopamine projection system.

  10. Emotion regulation and culture: are the social consequences of emotion suppression culture-specific?

    Science.gov (United States)

    Butler, Emily A; Lee, Tiane L; Gross, James J

    2007-02-01

    Emotional suppression has been associated with generally negative social consequences (Butler et al., 2003; Gross & John, 2003). A cultural perspective suggests, however, that these consequences may be moderated by cultural values. We tested this hypothesis in a two-part study, and found that, for Americans holding Western-European values, habitual suppression was associated with self-protective goals and negative emotion. In addition, experimentally elicited suppression resulted in reduced interpersonal responsiveness during face-to-face interaction, along with negative partner-perceptions and hostile behavior. These deleterious effects were reduced when individuals with more Asian values suppressed, and these reductions were mediated by cultural differences in the responsiveness of the suppressors. These findings suggest that many of suppression's negative social impacts may be moderated by cultural values. (c) 2007 APA, all rights reserved.

  11. Polypyrrole Actuators for Tremor Suppression

    DEFF Research Database (Denmark)

    Skaarup, Steen; Mogensen, Naja; Bay, Lasse

    2003-01-01

    Neurological tremor affecting limbs can be divided into at least 6 different types with frequencies ranging from 2 to about 20 Hz. In order to alleviate the symptoms by suppressing the tremor, sensing and actuation systems able to perform at these frequencies are needed. Electroactive polymers...... exemplify 'soft actuator' technology that may be especially suitable for use in conjunction with human limbs. The electrochemical and mechanical properties of polypyrrole dodecyl benzene sulphonate actuator films have been studied with this application in mind. The results show that the time constants...

  12. Suppression effects on musical and verbal memory.

    Science.gov (United States)

    Schendel, Zachary A; Palmer, Caroline

    2007-06-01

    Three experiments contrasted the effects of articulatory suppression on recognition memory for musical and verbal sequences. In Experiment 1, a standard/comparison task was employed, with digit or note sequences presented visually or auditorily while participants remained silent or produced intermittent verbal suppression (saying "the") or musical suppression (singing "la"). Both suppression types decreased performance by equivalent amounts, as compared with no suppression. Recognition accuracy was lower during suppression for visually presented digits than during that for auditorily presented digits (consistent with phonological loop predictions), whereas accuracy was equivalent for visually presented notes and auditory tones. When visual interference filled the retention interval in Experiment 2, performance with visually presented notes but not digits was impaired. Experiment 3 forced participants to translate visually presented music sequences by presenting comparison sequences auditorily. Suppression effects for visually presented music resembled those for digits only when the recognition task required sensory translation of cues.

  13. Pressure suppression pool thermal mixing

    International Nuclear Information System (INIS)

    Cook, D.H.

    1984-01-01

    A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing model is verified by comparing the model predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

  14. The role of suppression in amblyopia.

    Science.gov (United States)

    Li, Jingrong; Thompson, Benjamin; Lam, Carly S Y; Deng, Daming; Chan, Lily Y L; Maehara, Goro; Woo, George C; Yu, Minbin; Hess, Robert F

    2011-06-13

    This study had three main goals: to assess the degree of suppression in patients with strabismic, anisometropic, and mixed amblyopia; to establish the relationship between suppression and the degree of amblyopia; and to compare the degree of suppression across the clinical subgroups within the sample. Using both standard measures of suppression (Bagolini lenses and neutral density [ND] filters, Worth 4-Dot test) and a new approach involving the measurement of dichoptic motion thresholds under conditions of variable interocular contrast, the degree of suppression in 43 amblyopic patients with strabismus, anisometropia, or a combination of both was quantified. There was good agreement between the quantitative measures of suppression made with the new dichoptic motion threshold technique and measurements made with standard clinical techniques (Bagolini lenses and ND filters, Worth 4-Dot test). The degree of suppression was found to correlate directly with the degree of amblyopia within our clinical sample, whereby stronger suppression was associated with a greater difference in interocular acuity and poorer stereoacuity. Suppression was not related to the type or angle of strabismus when this was present or the previous treatment history. These results suggest that suppression may have a primary role in the amblyopia syndrome and therefore have implications for the treatment of amblyopia.

  15. Habit and Behavioral Intentions as Predictors of Social Behavior.

    Science.gov (United States)

    Landis, Dan; Triandis, Harry C; Adamopoulos, John

    1978-12-01

    This research assessed the relative impact of habit and behavioral intentions in predicting classroom teacher behavior, using a model proposed by Triandis. Responses from a behavioral differential, as well as two hours of classroom observations, were taken on 77 male and female black and white junior high school teachers. The classroom observation technique (STOIC) obtained the frequencies of emitted behaviors (both verbal and nonverbal), categorized by race and sex of the target child. Results indicated that habit was a more potent predictor of classroom behavior than intentions. However, a post-hoc analysis supported the notion that intentions become important when the habit component can be suppressed.

  16. Safety system for pressure suppression

    International Nuclear Information System (INIS)

    Wood, L.E.; Ludwig, G.J.; Tulsa, O.

    1975-01-01

    The rupture disk with rated breaking points is constrained by two supporting elements and has a convex-concave shape. For pressure suppression, it is reversable inversely to its bulging. Its surface has notches which are the rated breaking points and respond to higher pressures. The centre of the rupture disk contains an area of relatively smaller thickness that will burst at lower pressure and thus makes it applicable for lower pressures. For the response of the rupture disk centre, a thrust ring with a central opening may also be used. Its edge is formed into a convex-concave section supported on the edge of the rupture disk on the exit side. The free centre of the rupture disk is then the area of relative weakness. (RW/AK) [de

  17. Leptin Suppresses Mouse Taste Cell Responses to Sweet Compounds.

    Science.gov (United States)

    Yoshida, Ryusuke; Noguchi, Kenshi; Shigemura, Noriatsu; Jyotaki, Masafumi; Takahashi, Ichiro; Margolskee, Robert F; Ninomiya, Yuzo

    2015-11-01

    Leptin is known to selectively suppress neural and behavioral responses to sweet-tasting compounds. However, the molecular basis for the effect of leptin on sweet taste is not known. Here, we report that leptin suppresses sweet taste via leptin receptors (Ob-Rb) and KATP channels expressed selectively in sweet-sensitive taste cells. Ob-Rb was more often expressed in taste cells that expressed T1R3 (a sweet receptor component) than in those that expressed glutamate-aspartate transporter (a marker for Type I taste cells) or GAD67 (a marker for Type III taste cells). Systemically administered leptin suppressed taste cell responses to sweet but not to bitter or sour compounds. This effect was blocked by a leptin antagonist and was absent in leptin receptor-deficient db/db mice and mice with diet-induced obesity. Blocking the KATP channel subunit sulfonylurea receptor 1, which was frequently coexpressed with Ob-Rb in T1R3-expressing taste cells, eliminated the effect of leptin on sweet taste. In contrast, activating the KATP channel with diazoxide mimicked the sweet-suppressing effect of leptin. These results indicate that leptin acts via Ob-Rb and KATP channels that are present in T1R3-expressing taste cells to selectively suppress their responses to sweet compounds. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  18. MEK5 suppresses osteoblastic differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Kaneshiro, Shoichi [Department of Orthopaedic Surgery, Japan Community Health Care Organization Osaka Hospital, 4-2-78 Fukushima, Fukushima Ward, Osaka City, Osaka 553-0003 (Japan); Department of Orthopaedic Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Otsuki, Dai; Yoshida, Kiyoshi; Yoshikawa, Hideki [Department of Orthopaedic Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Higuchi, Chikahisa, E-mail: c-higuchi@umin.ac.jp [Department of Orthopaedic Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2015-07-31

    Extracellular signal-regulated kinase 5 (ERK5) is a member of the mitogen-activated protein kinase (MAPK) family and is activated by its upstream kinase, MAPK kinase 5 (MEK5), which is a member of the MEK family. Although the role of MEK5 has been investigated in several fields, little is known about its role in osteoblastic differentiation. In this study, we have demonstrated the role of MEK5 in osteoblastic differentiation in mouse preosteoblastic MC3T3-E1 cells and bone marrow stromal ST2 cells. We found that treatment with BIX02189, an inhibitor of MEK5, increased alkaline phosphatase (ALP) activity and the gene expression of ALP, osteocalcin (OCN) and osterix, as well as it enhanced the calcification of the extracellular matrix. Moreover, osteoblastic cell proliferation decreased at a concentration of greater than 0.5 μM. In addition, knockdown of MEK5 using siRNA induced an increase in ALP activity and in the gene expression of ALP, OCN, and osterix. In contrast, overexpression of wild-type MEK5 decreased ALP activity and attenuated osteoblastic differentiation markers including ALP, OCN and osterix, but promoted cell proliferation. In summary, our results indicated that MEK5 suppressed the osteoblastic differentiation, but promoted osteoblastic cell proliferation. These results implied that MEK5 may play a pivotal role in cell signaling to modulate the differentiation and proliferation of osteoblasts. Thus, inhibition of MEK5 signaling in osteoblasts may be of potential use in the treatment of osteoporosis. - Highlights: • MEK5 inhibitor BIX02189 suppresses proliferation of osteoblasts. • MEK5 knockdown and MEK5 inhibitor promote differentiation of osteoblasts. • MEK5 overexpression inhibits differentiation of osteoblasts.

  19. Charmonium formation and suppression in nuclear matter

    International Nuclear Information System (INIS)

    Xu Jiajun; Wang Jia; Zhuang Chao; Zhuang Pengfei

    2005-01-01

    The coupling Schroedinger equations describing the evolution of cc-bar states in nuclear matter are analytically and systematically solved via perturbation method, and the correlation between charmonium formation and nuclear absorption is investigated. After calculating J/Ψ and Ψ' suppression in nucleon-nucleus collisions and comparing with experiment data, it is found that the formation time effect plays an important rule in charmonium suppression, especially in Ψ' suppression. (authors)

  20. Poppers: more evidence of suppressed immunity.

    Science.gov (United States)

    James, J S

    1999-08-20

    Evidence from studies in mice shows that exposure to isobutyl nitrite suppresses the immune system. This immune suppression allows for bacterial growth in the lungs and livers of infected mice and can inhibit the ability of mediastinal lymph nodes to respond to antigen-specific stimulation. The mechanism for immune suppression may be a reduction in CD4+ and CD8+ T cell populations in the mediastinal lymph nodes following pulmonary infection with Listeria monocytogenes.

  1. Puberty suppression in adolescents with gender identity disorder: a prospective follow-up study.

    Science.gov (United States)

    de Vries, Annelou L C; Steensma, Thomas D; Doreleijers, Theo A H; Cohen-Kettenis, Peggy T

    2011-08-01

    Puberty suppression by means of gonadotropin-releasing hormone analogues (GnRHa) is used for young transsexuals between 12 and 16 years of age. The purpose of this intervention is to relieve the suffering caused by the development of secondary sex characteristics and to provide time to make a balanced decision regarding actual gender reassignment. To compare psychological functioning and gender dysphoria before and after puberty suppression in gender dysphoric adolescents. Of the first 70 eligible candidates who received puberty suppression between 2000 and 2008, psychological functioning and gender dysphoria were assessed twice: at T0, when attending the gender identity clinic, before the start of GnRHa; and at T1, shortly before the start of cross-sex hormone treatment. Behavioral and emotional problems (Child Behavior Checklist and the Youth-Self Report), depressive symptoms (Beck Depression Inventory), anxiety and anger (the Spielberger Trait Anxiety and Anger Scales), general functioning (the clinician's rated Children's Global Assessment Scale), gender dysphoria (the Utrecht Gender Dysphoria Scale), and body satisfaction (the Body Image Scale) were assessed. Behavioral and emotional problems and depressive symptoms decreased, while general functioning improved significantly during puberty suppression. Feelings of anxiety and anger did not change between T0 and T1. While changes over time were equal for both sexes, compared with natal males, natal females were older when they started puberty suppression and showed more problem behavior at both T0 and T1. Gender dysphoria and body satisfaction did not change between T0 and T1. No adolescent withdrew from puberty suppression, and all started cross-sex hormone treatment, the first step of actual gender reassignment. Puberty suppression may be considered a valuable contribution in the clinical management of gender dysphoria in adolescents. © 2010 International Society for Sexual Medicine.

  2. J/ψ-suppression in electro and hadroproduction

    International Nuclear Information System (INIS)

    Ducati, M.B. Gay

    1995-01-01

    We study the suppression of J/ψ production in lepton and hadroproduction on heavy nuclear targets and show that this phenomenon can be understood in terms of conventional physics, i.e. perturbative QCD, the parton recombination implementation of shadowing in the initial state, and the EMC effect, and final state interactions of the produced J/ψ production and its production via radiative χ decays (χJ → J/ψ + γ) and reproduce the experimental data including their small-x behavior. (author)

  3. Suppression of electromechanical instability in fiber-reinforced dielectric elastomers

    Directory of Open Access Journals (Sweden)

    Rui Xiao

    2016-03-01

    Full Text Available The electromechanical instability of dielectric elastomers has been a major challenge for the application of this class of active materials. In this work, we demonstrate that dielectric elastomers filled with soft fiber can suppress the electromechanical instability and achieve large deformation. Specifically, we developed a constitutive model to describe the dielectric and mechanical behaviors of fiber-reinforced elastomers. The model was applied to study the influence of stiffness, nonlinearity properties and the distribution of fiber on the instability of dielectric membrane under an electric field. The results show that there exists an optimal fiber distribution condition to achieve the maximum deformation before failure.

  4. Boiling Suppression in Convective Flow

    International Nuclear Information System (INIS)

    Aounallah, Y.

    2004-01-01

    The development of convective boiling heat transfer correlations and analytical models has almost exclusively been based on measurements of the total heat flux, and therefore on the overall two-phase heat transfer coefficient, when the well-known heat transfer correlations have often assumed additive mechanisms, one for each mode of heat transfer, convection and boiling. While the global performance of such correlations can readily be assessed, the predictive capability of the individual components of the correlation has usually remained elusive. This becomes important when, for example, developing mechanistic models for subcooled void formation based on the partitioning of the wall heat flux into a boiling and a convective component, or when extending a correlation beyond its original range of applications where the preponderance of the heat transfer mechanisms involved can be significantly different. A new examination of existing experimental heat transfer data obtained under fixed hydrodynamic conditions, whereby the local flow conditions are decoupled from the local heat flux, has allowed the unequivocal isolation of the boiling contribution over a broad range of thermodynamic qualities (0 to 0.8) for water at 7 MPa. Boiling suppression, as the quality increases, has consequently been quantified, thus providing valuable new insights on the functionality and contribution of boiling in convective flows. (author)

  5. Non-disruptive tactics of suppression are superior in countering terrorism, insurgency, and financial panics.

    Directory of Open Access Journals (Sweden)

    David A Siegel

    Full Text Available BACKGROUND: Suppressing damaging aggregate behaviors such as insurgency, terrorism, and financial panics are important tasks of the state. Each outcome of these aggregate behaviors is an emergent property of a system in which each individual's action depends on a subset of others' actions, given by each individual's network of interactions. Yet there are few explicit comparisons of strategies for suppression, and none that fully incorporate the interdependence of individual behavior. METHODS AND FINDINGS: Here I show that suppression tactics that do not require the removal of individuals from networks of interactions are nearly always more effective than those that do. I find using simulation analysis of a general model of interdependent behavior that the degree to which such less disruptive suppression tactics are superior to more disruptive ones increases in the propensity of individuals to engage in the behavior in question. CONCLUSIONS: Thus, hearts-and-minds approaches are generally more effective than force in counterterrorism and counterinsurgency, and partial insurance is usually a better tactic than gag rules in quelling financial panics. Differences between suppression tactics are greater when individual incentives to support terrorist or insurgent groups, or susceptibilities to financial panic, are higher. These conclusions have utility for policy-makers seeking to end bloody conflicts and prevent financial panics. As the model also applies to mass protest, its conclusions provide insight as well into the likely effects of different suppression strategies undertaken by authoritarian regimes seeking to hold on to power in the face of mass movements seeking to end them.

  6. Thermal stratification in a scaled-down suppression pool of the Fukushima Daiichi nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Byeongnam, E-mail: jo@vis.t.u-tokyo.ac.jp [Nuclear Professional School, The University of Tokyo, 2-22 Shirakata, Tokai-mura, Ibaraki 319-1188 (Japan); Erkan, Nejdet [Nuclear Professional School, The University of Tokyo, 2-22 Shirakata, Tokai-mura, Ibaraki 319-1188 (Japan); Takahashi, Shinji [Department of Nuclear Engineering and Management, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Song, Daehun [Nuclear Professional School, The University of Tokyo, 2-22 Shirakata, Tokai-mura, Ibaraki 319-1188 (Japan); Hyundai and Kia Corporate R& D Division, Hyundai Motors, 772-1, Jangduk-dong, Hwaseong-Si, Gyeonggi-Do 445-706 (Korea, Republic of); Sagawa, Wataru; Okamoto, Koji [Nuclear Professional School, The University of Tokyo, 2-22 Shirakata, Tokai-mura, Ibaraki 319-1188 (Japan)

    2016-08-15

    Highlights: • Thermal stratification was reproduced in a scaled-down suppression pool of the Fukushima Daiichi nuclear power plants. • Horizontal temperature profiles were uniform in the toroidal suppression pool. • Subcooling-steam flow rate map of thermal stratification was obtained. • Steam bubble-induced flow model in suppression pool was suggested. • Bubble frequency strongly depends on the steam flow rate. - Abstract: Thermal stratification in the suppression pool of the Fukushima Daiichi nuclear power plants was experimentally investigated in sub-atmospheric pressure conditions using a 1/20 scale torus shaped setup. The thermal stratification was reproduced in the scaled-down suppression pool and the effect of the steam flow rate on different thermal stratification behaviors was examined for a wide range of steam flow rates. A sparger-type steam injection pipe that emulated Fukushima Daiichi Unit 3 (F1U3) was used. The steam was injected horizontally through 132 holes. The development (formation and disappearance) of thermal stratification was significantly affected by the steam flow rate. Interestingly, the thermal stratification in the suppression pool vanished when subcooling became lower than approximately 5 °C. This occurred because steam bubbles are not well condensed at low subcooling temperatures; therefore, those bubbles generate significant upward momentum, leading to mixing of the water in the suppression pool.

  7. Keep calm! Gender differences in mental rotation performance are modulated by habitual expressive suppression.

    Science.gov (United States)

    Fladung, Anne-Katharina; Kiefer, Markus

    2016-11-01

    Men have been frequently found to perform more accurately than women in mental rotation tasks. However, men and women also differ with regard to the habitual use of emotion regulation strategies, particularly with regard to expressive suppression, i.e., the suppression of emotional expression in behavior. As emotional suppression is more often used by men, emotion regulation strategies might be a variable modulating gender differences in mental rotation performance. The present study, therefore, examined the influences of gender and emotion regulation strategies on mental rotation performance accuracy and feedback processing. Twenty-eight men and 28 women matched for relevant demographic variables performed mental rotation tasks of varying difficulty over a prolonged time. Emotional feedback was given immediately after each trial. Results showed that women reported to use expressive suppression less frequently than men. Women made more errors in the mental rotation task than men confirming earlier demonstrations of gender differences. Furthermore, women were more impaired by the negative feedback as indicated by the increased likelihood of subsequent errors compared with men. Task performance of women not habitually using expressive suppression was most inferior and most strongly influenced by failure feedback compared with men. Women using expressive suppression more habitually did not significantly differ in mental rotation accuracy and feedback processing from men. Hence, expressive suppression reduces gender differences in mental rotation accuracy by improving cognitive performance following failure feedback.

  8. Measuring ability to enhance and suppress emotional expression: The Flexible Regulation of Emotional Expression (FREE) Scale.

    Science.gov (United States)

    Burton, Charles L; Bonanno, George A

    2016-08-01

    Flexibility in self-regulatory behaviors has proved to be an important quality for adjusting to stressful life events and requires individuals to have a diverse repertoire of emotion regulation abilities. However, the most commonly used emotion regulation questionnaires assess frequency of behavior rather than ability, with little evidence linking these measures to observable capacity to enact a behavior. The aim of the current investigation was to develop and validate a Flexible Regulation of Emotional Expression (FREE) Scale that measures a person's ability to enhance and suppress displayed emotion across an array of hypothetical contexts. In Studies 1 and 2, a series of confirmatory factor analyses revealed that the FREE Scale consists of 4 first-order factors divided by regulation and emotional valence type that can contribute to 2 higher order factors: expressive enhancement ability and suppression ability. In Study 1, we also compared the FREE Scale to other commonly used emotion regulation measures, which revealed that suppression ability is conceptually distinct from suppression frequency. In Study 3, we compared the FREE Scale with a composite of traditional frequency-based indices of expressive regulation to predict performance in a previously validated emotional modulation paradigm. Participants' enhancement and suppression ability scores on the FREE Scale predicted their corresponding performance on the laboratory task, even when controlling for baseline expressiveness. These studies suggest that the FREE Scale is a valid and flexible measure of expressive regulation ability. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  9. Burst suppression probability algorithms: state-space methods for tracking EEG burst suppression

    Science.gov (United States)

    Chemali, Jessica; Ching, ShiNung; Purdon, Patrick L.; Solt, Ken; Brown, Emery N.

    2013-10-01

    Objective. Burst suppression is an electroencephalogram pattern in which bursts of electrical activity alternate with an isoelectric state. This pattern is commonly seen in states of severely reduced brain activity such as profound general anesthesia, anoxic brain injuries, hypothermia and certain developmental disorders. Devising accurate, reliable ways to quantify burst suppression is an important clinical and research problem. Although thresholding and segmentation algorithms readily identify burst suppression periods, analysis algorithms require long intervals of data to characterize burst suppression at a given time and provide no framework for statistical inference. Approach. We introduce the concept of the burst suppression probability (BSP) to define the brain's instantaneous propensity of being in the suppressed state. To conduct dynamic analyses of burst suppression we propose a state-space model in which the observation process is a binomial model and the state equation is a Gaussian random walk. We estimate the model using an approximate expectation maximization algorithm and illustrate its application in the analysis of rodent burst suppression recordings under general anesthesia and a patient during induction of controlled hypothermia. Main result. The BSP algorithms track burst suppression on a second-to-second time scale, and make possible formal statistical comparisons of burst suppression at different times. Significance. The state-space approach suggests a principled and informative way to analyze burst suppression that can be used to monitor, and eventually to control, the brain states of patients in the operating room and in the intensive care unit.

  10. Attentional selection and suppression in children and adults.

    Science.gov (United States)

    Sun, Meirong; Wang, Encong; Huang, Jing; Zhao, Chenguang; Guo, Jialiang; Li, Dongwei; Sun, Li; Du, Boqi; Ding, Yulong; Song, Yan

    2018-05-15

    The fundamental role of covert spatial attention is to enhance the processing of attended items while simultaneously ignoring irrelevant items. However, relatively little is known about how brain electrophysiological activities associated with target selection and distractor suppression are involved as they develop and become fully functional. The current study aimed to identify the neurophysiological bases of the development of covert spatial attention, focusing on electroencephalographic (EEG) markers of attentional selection (N2pc) and suppression (P D ). EEG data were collected from healthy young adults and typically developing children (9-15 years old) as they searched for a shape singleton target in either the absence or the presence of a salient-but-irrelevant color singleton distractor. The ERP results showed that a lateral shape target elicited a smaller N2pc in children compared with adults regardless of whether a distractor was present or not. Moreover, the target-elicited N2pc was always followed by a similar positivity in both age groups. Counterintuitively, a lateral salient-but-irrelevant distractor elicited a large P D in children with low behavioral accuracy, whereas high-accuracy children exhibited a small and "adult-like" P D . More importantly, we found no evidence for a correlation between the target-elicited N2pc and the distractor-elicited P D in either age group. Our results provide neurophysiological evidence for the developmental differences between target selection and distractor suppression. Compared with adults, 9-15-year-old children deploy insufficient attentional selection resources to targets but use "adult-like" or even more attentional suppression resources to resist irrelevant distractors. A video abstract of this article can be viewed at: https://www.youtube.com/watch?v=NhWapx0d75I. © 2018 John Wiley & Sons Ltd.

  11. Psychopathology and Thought Suppression: A Quantitative Review

    Science.gov (United States)

    Magee, Joshua C.; Harden, K. Paige; Teachman, Bethany A.

    2012-01-01

    Recent theories of psychopathology have suggested that thought suppression intensifies the persistence of intrusive thoughts, and proposed that difficulty with thought suppression may differ between groups with and without psychopathology. The current meta-analytic review evaluates empirical evidence for difficulty with thought suppression as a function of the presence and specific type of psychopathology. Based on theoretical proposals from the psychopathology literature, diagnosed and analogue samples were expected to show greater recurrence of intrusive thoughts during thought suppression attempts than non-clinical samples. However, results showed no overall differences in the recurrence of thoughts due to thought suppression between groups with and without psychopathology. There was, nevertheless, variation in the recurrence of thoughts across different forms of psychopathology, including relatively less recurrence during thought suppression for samples with symptoms of Obsessive-Compulsive Disorder, compared to non-clinical samples. However, these differences were typically small and provided only mixed support for existing theories. Implications for cognitive theories of intrusive thoughts are discussed, including proposed mechanisms underlying thought suppression. PMID:22388007

  12. Volatile suppressing method for radioactive iodine

    International Nuclear Information System (INIS)

    Ohara, Atsushi; Haruguchi, Keiko.

    1997-01-01

    In the present invention, a metal plate is disposed above the pool water surface of a suppression chamber disposed to a reactor container in order to reduce evaporation of radioactive iodine released from a suppression pool. A metal plate is disposed above the pool water surface of the suppression chamber disposed to the reactor container. In addition, a metal plate is disposed around the space connecting a bent tube extending from a dry well to underwater of suppression pool water and a gas bent tube extending from the suppression chamber to an emergency gas processing system. Spray water is supplied for cooling the suppression chamber d as a means for cooling the metal plate. Then, among iodine released to the suppression chamber, elemental iodine liberated from the pool water is deposited on the surface of the metal plate, and the amount of iodine to be flown into and processed by an emergency gas processing system or a filter bent system can be reduced. (T.M.)

  13. Regional Extent of Peripheral Suppression in Amblyopia.

    Science.gov (United States)

    Babu, Raiju J; Clavagnier, Simon; Bobier, William R; Thompson, Benjamin; Hess, Robert F

    2017-04-01

    Previously, we have mapped amblyopic eye suppression within the central 20° of the visual field and observed a gradient of suppression that is strongest in central vision and weakens with increasing eccentricity. In this study, using a large dichoptic display, we extend our novel suppression mapping approach further into the periphery (from 20°-60°) to assess whether suppression continues to decline with eccentricity or plateaus. Sixteen participants with amblyopia (10 with strabismus, 6 with anisometropia without strabismus; mean age: 37.9 ± 11 years) and six normal observers (mean age: 28.3 ± 5 years) took part. The visual stimulus (60° diameter), viewed from 57 cm, was composed of four concentric annuli (5° radius) with alternate contrast polarities starting from an eccentricity of 10°. Each annulus was divided into eight sectors subtending 45° of visual angle. Participants adjusted the contrast of a single sector presented to the fellow eye to match the perceived contrast of the remaining stimulus elements that were presented to the amblyopic eye. A matching contrast that was lower in the fellow eye than the amblyopic eye indicated suppression. Patients with strabismus exhibited significantly stronger interocular suppression than controls across all eccentricities (P = 0.01). Patients with anisometropia did not differ from controls (P = 0.58). Suppression varied significantly with eccentricity (P = 0.005) but this effect did not differ between patient groups (P = 0.217). In amblyopia, suppression is present beyond the central 10° in patients with strabismus. Suppression becomes weaker at greater eccentricities and this may enable peripheral fusion that could be used by binocular treatment methods.

  14. Suppression of stochastic pulsation in laser-plasma interaction by smoothing methods

    International Nuclear Information System (INIS)

    Hora, H.; Aydin, M.

    1992-01-01

    The control of the very complex behavior of a plasma with laser interaction by smoothing with induced spatial incoherence or other methods was related to improving the lateral uniformity of the irradiation. While this is important, it is shown from numerical hydrodynamic studies that the very strong temporal pulsation (stuttering) will mostly be suppressed by these smoothing methods too

  15. Relative left frontal activity in reappraisal and suppression of negative emotion: Evidence from frontal alpha asymmetry (FAA).

    Science.gov (United States)

    Choi, Damee; Sekiya, Takahiro; Minote, Natsumi; Watanuki, Shigeki

    2016-11-01

    Previous studies have shown that reappraisal (changing the way that one thinks about emotional events) is an effective strategy for regulating emotion, compared with suppression (reducing emotion-expressive behavior). In the present study, we investigated relative left frontal activity when participants were instructed to use reappraisal and suppression of negative emotion, by measuring frontal alpha asymmetry (FAA). Two electroencephalography (EEG) experiments were conducted; FAA was analyzed while 102 healthy participants (59 men, 43 women) watched negative images after being instructed to perform reappraisal (Experiment 1) and suppression (Experiment 2). Habitual use of reappraisal and suppression was also assessed using the emotion regulation questionnaire (ERQ). The results of Experiment 1 showed that relative left frontal activity was greater when instructed to use reappraisal of negative images than when normally viewing negative images. In contrast, we observed no difference between conditions of instructed suppression and normal viewing in Experiment 2. In addition, in male participants, habitual use of reappraisal was positively correlated with increased relative left frontal activity for instructed reappraisal, while habitual use of suppression did not show a significant correlation with changes in relative left frontal activity for instructed suppression. These results suggest that emotional responses to negative images might be decreased for instructed reappraisal, but not suppression. These findings support previous reports that reappraisal is an effective emotion regulation strategy, compared with suppression. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Chondromalacia patellae: fat-suppressed MR imaging.

    Science.gov (United States)

    Rose, P M; Demlow, T A; Szumowski, J; Quinn, S F

    1994-11-01

    To evaluate the accuracy of fat-suppressed magnetic resonance (MR) imaging in diagnosing chondromalacia patellae. Seventy-one patients underwent fat-suppressed MR imaging and arthroscopy of the patellofemoral compartment. Findings were classified as early or advanced chondromalacia or as normal and were correlated with arthroscopic findings. Early and advanced stages of chondromalacia patellae were reliably detected, with positive predictive values of 85% and 92%, respectively. Specificity in early stages was 94% and in late stages was 98%. However, the overall accuracies did not differ substantially from those reported in studies that did not use fat-suppressed imaging. Axial, fat-suppressed MR imaging accurately depicts changes caused by chondromalacia patellae. Early stages can be seen as intrasubstance changes of increased signal intensity. Results of this study suggest a high degree of specificity in excluding both early and advanced changes.

  17. METHOD OF SUPPRESSING GASTROINTESTINAL UREASE ACTIVITY

    Science.gov (United States)

    Visek, W.J.

    1963-04-23

    This patent shows a method of increasing the growth rate of chicks. Certain diacyl substituted ureas such as alloxan, murexide, and barbituric acid are added to their feed, thereby suppressing gastrointestinal urease activity and thus promoting growth. (AEC)

  18. Suppression factors in diffractive photoproduction of dijets

    International Nuclear Information System (INIS)

    Klasen, Michael; Kramer, Gustav

    2010-06-01

    After new publications of H1 data for the diffractive photoproduction of dijets, which overlap with the earlier published H1 data and the recently published data of the ZEUS collaboration, have appeared, we have recalculated the cross sections for this process in next-to-leading order (NLO) of perturbative QCD to see whether they can be interpreted consistently. The results of these calculations are compared to the data of both collaborations. We find that the NLO cross sections disagree with the data, showing that factorization breaking occurs at that order. If direct and resolved contributions are both suppressed by the same amount, the global suppression factor depends on the transverse-energy cut. However, by suppressing only the resolved contribution, also reasonably good agreement with all the data is found with a suppression factor independent of the transverse-energy cut. (orig.)

  19. Attention modulates sensory suppression during back movements.

    Science.gov (United States)

    Van Hulle, Lore; Juravle, Georgiana; Spence, Charles; Crombez, Geert; Van Damme, Stefaan

    2013-06-01

    Tactile perception is often impaired during movement. The present study investigated whether such sensory suppression also occurs during back movements, and whether this would be modulated by attention. In two tactile detection experiments, participants simultaneously engaged in a movement task, in which they executed a back-bending movement, and a perceptual task, consisting of the detection of subtle tactile stimuli administered to their upper or lower back. The focus of participants' attention was manipulated by raising the probability that one of the back locations would be stimulated. The results revealed that tactile detection was suppressed during the execution of the back movements. Furthermore, the results of Experiment 2 revealed that when the stimulus was always presented to the attended location, tactile suppression was substantially reduced, suggesting that sensory suppression can be modulated by top-down attentional processes. The potential of this paradigm for studying tactile information processing in clinical populations is discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Suppression of instability in rotatory hydromagnetic convection

    Indian Academy of Sciences (India)

    first time by Lord Rayleigh [9] for the idealized case of two free boundaries. Rayleigh's theory shows that the gravity-dominated thermal instability in liquid layer ... suppressed for oscillatory perturbations by the simultaneous application of a ...

  1. Combustion suppressing device for leaked sodium

    International Nuclear Information System (INIS)

    Ooto, Akihiro.

    1985-01-01

    Purpose: To suppress the atmospheric temperature to secure the building safety and shorten the recovery time after the leakage in a chamber for containing sodium leaked from coolant circuit equipments or pipeways of LMFBR type rector by suppressing the combustion of sodium contained in the chamber. Constitution: To the inner wall of a chamber for containing sodium handling equipments, are vertically disposed a panel having a coolant supply port at the upper portion and a coolant discharge port at the lower portion thereof and defined with a coolant flowing channel and a panel for sucking the coolant discharged from the abovementioned panel and exhausting the same externally. Further, a corrugated combustion suppressing plate having apertures for draining the condensated leaked sodium is disposed near the sodium handling equipments. If ruptures are resulted to the sodium handling equipments or pipeway, leaked sodium is passed through the drain apertures in the suppressing plate and stored at the bottom of the containing chamber. (Horiuchi, T.)

  2. Suppressing Tsetse Flies to Improve Lives

    International Nuclear Information System (INIS)

    Potterton, Louise; Pavlicek, Petr; Parker, Andrew

    2013-01-01

    In 2009, the government-run Southern Tsetse Eradication Project (STEP) in Ethiopia, with the support of the IAEA, started to carry out intensive activities to suppress the fly population using insecticides. The fly population is now down by 90%. The benefits of tsetse suppression can be seen all over the region. Diary produce is now widely available at markets and healthy animals can be seen everywhere in farming and transport

  3. Gamma camera scatter suppression unit WAM

    International Nuclear Information System (INIS)

    Kishi, Haruo; Shibahara, Noriyuki; Hirose, Yoshiharu; Shimonishi, Yoshihiro; Oumura, Masahiro; Ikeda, Hozumi; Hamada, Kunio; Ochi, Hironobu; Itagane, Hiroshi.

    1990-01-01

    In gamma camera imaging, scattered radiation is one of big factors to decrease image contrast. Simply, scatter suppression makes signal to noise ratio larger, but it makes statistics error because of radionuclide injection limit to the human body. EWA is a new method that suppresses scattered radiation and improves image contrast. In this article, WAM which is commercialized EWA method by Siemens Gammasonics Inc. is presented. (author)

  4. Suppression sours sacrifice: emotional and relational costs of suppressing emotions in romantic relationships.

    Science.gov (United States)

    Impett, Emily A; Kogan, Aleksandr; English, Tammy; John, Oliver; Oveis, Christopher; Gordon, Amie M; Keltner, Dacher

    2012-06-01

    What happens when people suppress their emotions when they sacrifice for a romantic partner? This multimethod study investigates how suppressing emotions during sacrifice shapes affective and relationship outcomes. In Part 1, dating couples came into the laboratory to discuss important romantic relationship sacrifices. Suppressing emotions was associated with emotional costs for the partner discussing his or her sacrifice. In Part 2, couples participated in a 14-day daily experience study. Within-person increases in emotional suppression during daily sacrifice were associated with decreases in emotional well-being and relationship quality as reported by both members of romantic dyads. In Part 3, suppression predicted decreases in relationship satisfaction and increases in thoughts about breaking up with a romantic partner 3 months later. In the first two parts of the study, authenticity mediated the costly effects of suppression. Implications for research on close relationships and emotion regulation are discussed.

  5. Cognitive and neural consequences of memory suppression in major depressive disorder.

    Science.gov (United States)

    Sacchet, Matthew D; Levy, Benjamin J; Hamilton, J Paul; Maksimovskiy, Arkadiy; Hertel, Paula T; Joormann, Jutta; Anderson, Michael C; Wagner, Anthony D; Gotlib, Ian H

    2017-02-01

    Negative biases in cognition have been documented consistently in major depressive disorder (MDD), including difficulties in the ability to control the processing of negative material. Although negative information-processing biases have been studied using both behavioral and neuroimaging paradigms, relatively little research has been conducted examining the difficulties of depressed persons with inhibiting the retrieval of negative information from long-term memory. In this study, we used the think/no-think paradigm and functional magnetic resonance imaging to assess the cognitive and neural consequences of memory suppression in individuals diagnosed with depression and in healthy controls. The participants showed typical behavioral forgetting effects, but contrary to our hypotheses, there were no differences between the depressed and nondepressed participants or between neutral and negative memories. Relative to controls, depressed individuals exhibited greater activity in right middle frontal gyrus during memory suppression, regardless of the valence of the suppressed stimuli, and differential activity in the amygdala and hippocampus during memory suppression involving negatively valenced stimuli. These findings indicate that depressed individuals are characterized by neural anomalies during the suppression of long-term memories, increasing our understanding of the brain bases of negative cognitive biases in MDD.

  6. Reward enhances tic suppression in children within months of tic disorder onset

    Directory of Open Access Journals (Sweden)

    Deanna J. Greene

    2015-02-01

    Full Text Available Tic disorders are childhood onset neuropsychiatric disorders characterized by motor and/or vocal tics. Research has demonstrated that children with chronic tics (including Tourette syndrome and Chronic Tic Disorder: TS/CTD can suppress tics, particularly when an immediate, contingent reward is given for successful tic suppression. As a diagnosis of TS/CTD requires tics to be present for at least one year, children in these tic suppression studies had been living with tics for quite some time. Thus, it is unclear whether the ability to inhibit tics is learned over time or present at tic onset. Resolving that issue would inform theories of how tics develop and how behavior therapy for tics works. We investigated tic suppression in school-age children as close to the time of tic onset as possible, and no later than six months after onset. Children were asked to suppress their tics both in the presence and absence of a contingent reward. Results demonstrated that these children, like children with TS/CTD, have some capacity to suppress tics, and that immediate reward enhances that capacity. These findings demonstrate that the modulating effect of reward on inhibitory control of tics is present within months of tic onset, before tics have become chronic.

  7. Reward enhances tic suppression in children within months of tic disorder onset.

    Science.gov (United States)

    Greene, Deanna J; Koller, Jonathan M; Robichaux-Viehoever, Amy; Bihun, Emily C; Schlaggar, Bradley L; Black, Kevin J

    2015-02-01

    Tic disorders are childhood onset neuropsychiatric disorders characterized by motor and/or vocal tics. Research has demonstrated that children with chronic tics (including Tourette syndrome and Chronic Tic Disorder: TS/CTD) can suppress tics, particularly when an immediate, contingent reward is given for successful tic suppression. As a diagnosis of TS/CTD requires tics to be present for at least one year, children in these tic suppression studies had been living with tics for quite some time. Thus, it is unclear whether the ability to inhibit tics is learned over time or present at tic onset. Resolving that issue would inform theories of how tics develop and how behavior therapy for tics works. We investigated tic suppression in school-age children as close to the time of tic onset as possible, and no later than six months after onset. Children were asked to suppress their tics both in the presence and absence of a contingent reward. Results demonstrated that these children, like children with TS/CTD, have some capacity to suppress tics, and that immediate reward enhances that capacity. These findings demonstrate that the modulating effect of reward on inhibitory control of tics is present within months of tic onset, before tics have become chronic. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Repetition suppression and multi-voxel pattern similarity differentially track implicit and explicit visual memory.

    Science.gov (United States)

    Ward, Emily J; Chun, Marvin M; Kuhl, Brice A

    2013-09-11

    Repeated exposure to a visual stimulus is associated with corresponding reductions in neural activity, particularly within visual cortical areas. It has been argued that this phenomenon of repetition suppression is related to increases in processing fluency or implicit memory. However, repetition of a visual stimulus can also be considered in terms of the similarity of the pattern of neural activity elicited at each exposure--a measure that has recently been linked to explicit memory. Despite the popularity of each of these measures, direct comparisons between the two have been limited, and the extent to which they differentially (or similarly) relate to behavioral measures of memory has not been clearly established. In the present study, we compared repetition suppression and pattern similarity as predictors of both implicit and explicit memory. Using functional magnetic resonance imaging, we scanned 20 participants while they viewed and categorized repeated presentations of scenes. Repetition priming (facilitated categorization across repetitions) was used as a measure of implicit memory, and subsequent scene recognition was used as a measure of explicit memory. We found that repetition priming was predicted by repetition suppression in prefrontal, parietal, and occipitotemporal regions; however, repetition priming was not predicted by pattern similarity. In contrast, subsequent explicit memory was predicted by pattern similarity (across repetitions) in some of the same occipitotemporal regions that exhibited a relationship between priming and repetition suppression; however, explicit memory was not related to repetition suppression. This striking double dissociation indicates that repetition suppression and pattern similarity differentially track implicit and explicit learning.

  9. REWARD ENHANCES TIC SUPPRESSION IN CHILDREN WITHIN MONTHS OF TIC DISORDER ONSET

    Science.gov (United States)

    Greene, Deanna J.; Koller, Jonathan M.; Robichaux-Viehoever, Amy; Bihun, Emily C.; Schlaggar, Bradley L.; Black, Kevin J.

    2014-01-01

    Tic disorders are childhood onset neuropsychiatric disorders characterized by motor and/or vocal tics. Research has demonstrated that children with chronic tics (including Tourette syndrome and Chronic Tic Disorder: TS/CTD) can suppress tics, particularly when an immediate, contingent reward is given for successful tic suppression. As a diagnosis of TS/CTD requires tics to be present for at least one year, children in these tic suppression studies had been living with tics for quite some time. Thus, it is unclear whether the ability to inhibit tics is learned over time or present at tic onset. Resolving that issue would inform theories of how tics develop and how behavior therapy for tics works. We investigated tic suppression in school-age children as close to the time of tic onset as possible, and no later than six months after onset. Children were asked to suppress their tics both in the presence and absence of a contingent reward. Results demonstrated that these children, like children with TS/CTD, have some capacity to suppress tics, and that immediate reward enhances that capacity. These findings demonstrate that the modulating effect of reward on inhibitory control of tics is present within months of tic onset, before tics have become chronic. PMID:25220075

  10. A compact clinical instrument for quantifying suppression.

    Science.gov (United States)

    Black, Joanne M; Thompson, Benjamin; Maehara, Goro; Hess, Robert F

    2011-02-01

    We describe a compact and convenient clinical apparatus for the measurement of suppression based on a previously reported laboratory-based approach. In addition, we report and validate a novel, rapid psychophysical method for measuring suppression using this apparatus, which makes the technique more applicable to clinical practice. By using a Z800 dual pro head-mounted display driven by a MAC laptop, we provide dichoptic stimulation. Global motion stimuli composed of arrays of moving dots are presented to each eye. One set of dots move in a coherent direction (termed signal) whereas another set of dots move in a random direction (termed noise). To quantify performance, we measure the signal/noise ratio corresponding to a direction-discrimination threshold. Suppression is quantified by assessing the extent to which it matters which eye sees the signal and which eye sees the noise. A space-saving, head-mounted display using current video technology offers an ideal solution for clinical practice. In addition, our optimized psychophysical method provided results that were in agreement with those produced using the original technique. We made measures of suppression on a group of nine adult amblyopic participants using this apparatus with both the original and new psychophysical paradigms. All participants had measurable suppression ranging from mild to severe. The two different psychophysical methods gave a strong correlation for the strength of suppression (rho = -0.83, p = 0.006). Combining the new apparatus and new psychophysical method creates a convenient and rapid technique for parametric measurement of interocular suppression. In addition, this apparatus constitutes the ideal platform for suppressors to combine information between their eyes in a similar way to binocularly normal people. This provides a convenient way for clinicians to implement the newly proposed binocular treatment of amblyopia that is based on antisuppression training.

  11. CONDITIONS FOR CSR MICROBUNCHING GAIN SUPPRESSION

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Cheng Ying [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Li, Rui [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tennant, Christopher D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); di Mitri, Simone [Elettra–Sincrotrone Trieste, 34149 Basovizza, Trieste, Italy

    2016-05-01

    The coherent synchrotron radiation (CSR) of a high brightness electron beam traversing a series of dipoles, such as transport arcs, may result in phase space degradation. On one hand, the CSR can perturb electron transverse motion in dispersive regions along the beamline, causing emittance growth. On the other hand, the CSR effect on the longitudinal beam dynamics could result in microbunching gain enhancement. For transport arcs, several schemes have been proposed* to suppress the CSR-induced emittance growth. Similarly, several scenarios have been introduced** to suppress CSR-induced microbunching gain, which however mostly aim for linac-based machines. In this paper we try to provide sufficient conditions for suppression of CSR-induced microbunching gain along a transport arc, analogous to*. Several example lattices are presented, with the relevant microbunching analyses carried out by our semi-analytical Vlasov solver***. The simulation results show that lattices satisfying the proposed conditions indeed have microbunching gain suppressed. We expect this analysis can shed light on lattice design approach that could suppress the CSR-induced microbunching gain.

  12. Interocular suppression in children with deprivation amblyopia.

    Science.gov (United States)

    Hamm, Lisa; Chen, Zidong; Li, Jinrong; Black, Joanna; Dai, Shuan; Yuan, Junpeng; Yu, Minbin; Thompson, Benjamin

    2017-04-01

    In patients with anisometropic or strabismic amblyopia, interocular suppression can be minimized by presenting high contrast stimulus elements to the amblyopic eye and lower contrast elements to the fellow eye. This suggests a structurally intact binocular visual system that is functionally suppressed. We investigated whether suppression can also be overcome by contrast balancing in children with deprivation amblyopia due to childhood cataracts. To quantify interocular contrast balance, contrast interference thresholds were measured using an established dichoptic global motion technique for 21 children with deprivation amblyopia, 14 with anisometropic or mixed strabismic/anisometropic amblyopia and 10 visually normal children (mean age mean=9.9years, range 5-16years). We found that interocular suppression could be overcome by contrast balancing in most children with deprivation amblyopia, at least intermittently, and all children with anisometropic or mixed anisometropic/strabismic amblyopia. However, children with deprivation amblyopia due to early unilateral or bilateral cataracts could tolerate only very low contrast levels to the stronger eye indicating strong suppression. Our results suggest that treatment options reliant on contrast balanced dichoptic presentation could be attempted in a subset of children with deprivation amblyopia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Fear Expression Suppresses Medial Prefrontal Cortical Firing in Rats.

    Directory of Open Access Journals (Sweden)

    Thomas F Giustino

    Full Text Available The medial prefrontal cortex (mPFC plays a crucial role in emotional learning and memory in rodents and humans. While many studies suggest a differential role for the prelimbic (PL and infralimbic (IL subdivisions of mPFC, few have considered the relationship between neural activity in these two brain regions recorded simultaneously in behaving animals. Importantly, how concurrent PL and IL activity relate to conditioned freezing behavior is largely unknown. Here we used single-unit recordings targeting PL and IL in awake, behaving rats during the acquisition and expression of conditioned fear. On Day 1, rats received either signaled or unsignaled footshocks in the recording chamber; an auditory conditioned stimulus (CS preceded signaled footshocks. Twenty-four hours later, animals were returned to the recording chamber (modified to create a novel context where they received 5 CS-alone trials. After fear conditioning, both signaled and unsignaled rats exhibited high levels of post-shock freezing that was associated with an enduring suppression of mPFC spontaneous firing, particularly in the IL of signaled rats. Twenty-four hours later, CS presentation produced differential conditioned freezing in signaled and unsignaled rats: freezing increased in rats that had received signaled shocks, but decreased in animals in the unsignaled condition (i.e., external inhibition. This group difference in CS-evoked freezing was mirrored in the spontaneous firing rate of neurons in both PL and IL. Interestingly, differences in PL and IL firing rate highly correlated with freezing levels. In other words, in the signaled group IL spontaneous rates were suppressed relative to PL, perhaps limiting IL-mediated suppression of fear and allowing PL activity to dominate performance, resulting in high levels of freezing. This was not observed in the unsignaled group, which exhibited low freezing. These data reveal that the activity of mPFC neurons is modulated by both

  14. Effects of thought suppression on episodic memory.

    Science.gov (United States)

    Rassin, E; Merckelbach, H; Muris, P

    1997-11-01

    Subjects were shown a short film fragment. Following this, one group of subjects (n = 26) was instructed to suppress their thoughts about the film, while the other group (n = 24) received no instructions. After 5 hrs subjects returned to the laboratory and completed a questionnaire testing their memory about the film. Results showed that suppression subjects reported a higher frequency of thoughts about the film than control subjects. No evidence was obtained for Wegner, Quillian, and Houston's (1996; Journal of Personality and Social Psychology, 71, 680-691) claim that suppression has an undermining effect on memory for chronology. Possible causes for the differences between the results as obtained by Wegner et al., and those found in the present study are discussed. These causes may pertain to the experimental design, but also to differences in emotional impact of the stimulus material that was used in both studies.

  15. Wing rock suppression using forebody vortex control

    Science.gov (United States)

    Ng, T. T.; Ong, L. Y.; Suarez, C. J.; Malcolm, G. N.

    1991-01-01

    Static and free-to-roll tests were conducted in a water tunnel with a configuration that consisted of a highly-slender forebody and 78-deg sweep delta wings. Flow visualization was performed and the roll angle histories were obtained. The fluid mechanisms governing the wing rock of this configuration were identified. Different means of suppressing wing rock by controlling the forebody vortices using small blowing jets were also explored. Steady blowing was found to be capable of suppressing wing rock, but significant vortex asymmetries had to be induced at the same time. On the other hand, alternating pulsed blowing on the left and right sides of the forebody was demonstrated to be potentially an effective means of suppressing wing rock and eliminating large asymmetric moments at high angles of attack.

  16. Quantum-mechanical suppression of bremsstrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Becker-Szendy, R.; Keller, L.; Niemi, G.; Perl, M.; Rochester, L. [Stanford Univ., CA (United States); Anthony, P. [Stanford Univ., CA (United States)]|[Lawrence Livermore National Lab., CA (United States); Bosted, P. [American Univ., Washington, DC (United States); Cavalli-Sforza, M.; Kelley, L.; Klein, S. [Univ. of California, Santa Cruz, CA (United States)] [and others

    1994-12-01

    The authors have studied quantum-mechanical suppression of bremsstrahlung of low-energy 1-500 MeV photons from high-energy 25 GeV electrons. They have measured the LPM effect, where multiple scattering of the radiating electron destroys coherence required for the emission of low-energy photons, and the dielectric effect, where the emitted photon traveling in the radiator medium interferes with itself. For the experiment, the collaboration developed a novel method of extracting a parasitic low-intensity high-energy electron beam into the fixed target area during normal SLC operation of the accelerator. The results agree quantitatively with Migdal`s calculation of the LPM effect. Surface effects, for which there is no satisfactory theoretical prediction, are visible at low photon energies. For very thin targets, the suppression disappears, as expected. Preliminary results on dielectric suppression of bremsstrahlung are in qualitative agreement with the expectation.

  17. Shielding design of ITER pressure suppression system

    International Nuclear Information System (INIS)

    Yamauchi, Michinori; Sato, Satoshi; Nishitani, Takeo; Kawasaki, Hiromitsu

    2006-01-01

    The duct shield from streaming D-T neutrons has been designed for the ITER pressure suppression system. Streaming calculations are performed with the DUCT-III code for the region from the inlet of the pressure relief line to the rupture disk. Next, the neutron permeation through the shield is studied by Monte Carlo calculations with the MCNP code. It is found that 0.15 m thick iron shield is enough to suppress the permeating component from the outside. In addition, it is suggested that the volume of the shield can be reduced by about 30% if the optimized iron shield structure having localized thickness across intense permeation paths is employed to shield the pressure suppression line. (T.I.)

  18. Suppression of charmonium production in hadron gas

    International Nuclear Information System (INIS)

    Faustov, R.N.; Vasilevskaya, I.G.

    1991-01-01

    The problem of J/ψ charmonium production suppression under heavy ion collisions is investigated. The processes of charmonium disintegration in hadron gas are considered: π+J/ψ → π+c+c-bar and ρ+J/ψ → D+D. Based on the results obtained one can assume that charmonium disintegration contribution to J/ψ production suppression under collisions with gas hadrons and the contribution conditioned by the production of quark-gluon plasma, appear to be the effects of similar order of magnitude

  19. Jet suppression measurement with the ATLAS detector

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00443411; The ATLAS collaboration

    2016-01-01

    A hot medium with a high density of unscreened color charges is produced in relativistic heavy ion collisions. Jets are produced at the early stages of this collision and are known to become attenuated as they propagate through the hot matter. One manifestation of this energy loss is a lower yield of jets emerging from the medium than expected in the absence of medium effects. Another manifestation of the energy loss is the modification of the dijet balance and the modification of fragmentation functions. In these proceedings, the latest ATLAS results on single jet suppression, dijet suppression, and modification of the jet internal structure in \\PbPb~collisions are presented.

  20. Star formation suppression in compact group galaxies

    DEFF Research Database (Denmark)

    Alatalo, K.; Appleton, P. N.; Lisenfeld, U.

    2015-01-01

    , bars, rings, tidal tails, and possibly nuclear outflows, though the molecular gas morphologies are more consistent with spirals and earlytype galaxies than mergers and interacting systems. Our CO-imaged HCG galaxies, when plotted on the Kennicutt-Schmidt relation, shows star formation (SF) suppression...... color space. This supports the idea that at least some galaxies in HCGs are transitioning objects, where a disruption of the existing molecular gas in the system suppresses SF by inhibiting the molecular gas from collapsing and forming stars efficiently. These observations, combined with recent work...

  1. Pressure suppression pool mixing in passive advanced BWR plants

    International Nuclear Information System (INIS)

    Gamble, Robert E.; Nguyen, Thuy T.; Shiralkar, Bharat S.; Peterson, Per F.; Greif, Ralph; Tabata, H.

    2001-01-01

    In the SBWR passive boiling water reactor, the long-term post-accident containment pressure is determined by the combination of noncondensible gas pressure and steam pressure in the wetwell gas space. The suppression pool (SP) surface temperature, which determines the vapor partial pressure, is very important to overall containment performance. Therefore, the thermal stratification of the SP due to blowdown is of primary importance. This work looks at the various phases and phenomena present during the blowdown event and identifies those that are important to thermal stratification, and the scaling necessary to model them in reduced size tests. This is important in determining which of the large body of blowdown to SP data is adequate for application to the stratification problem. The mixing by jets from the main vents is identified as the key phenomena influencing the thermal response of the suppression pool and analytical models are developed to predict the jet influence on thermal stratification. The analytical models are implemented into a system simulation code, TRACG, and used to model thermal stratification behavior in a scaled test facility. The results show good general agreement with the test data

  2. Suppression of Fatigue Crack Propagation of Duralumin by Cavitation Peening

    Directory of Open Access Journals (Sweden)

    Hitoshi Soyama

    2015-08-01

    Full Text Available It was demonstrated in the present paper that cavitation peening which is one of the mechanical surface modification technique can suppress fatigue crack propagation in duralumin. The impacts produced when cavitation bubble collapses can be utilised for the mechanical surface modification technique in the same way as laser peening and shot peening, which is called “cavitation peening”. Cavitation peening employing a cavitating jet in water was used to treat the specimen made of duralumin Japanese Industrial Standards JIS A2017-T3. After introducing a notch, fatigue test was conducted by a load-controlled plate bending fatigue tester, which has been originally developed. The fatigue crack propagation behavior was evaluated and the relationship between the fatigue crack propagation rate versus stress intensity factor range was obtained. From the results, the fatigue crack propagation rate was drastically reduced by cavitation peening and the fatigue life of duralumin plate was extended 4.2 times by cavitation peening. In addition, the fatigue crack propagation can be suppressed by 88% in the stable crack propagation stage by cavitation peening.

  3. Parallel magnetic field suppresses dissipation in superconducting nanostrips

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yong-Lei; Glatz, Andreas; Kimmel, Gregory J.; Aranson, Igor S.; Thoutam, Laxman R.; Xiao, Zhi-Li; Berdiyorov, Golibjon R.; Peeters, François M.; Crabtree, George W.; Kwok, Wai-Kwong

    2017-11-13

    The motion of Abrikosov vortices in type-II superconductors results in a finite resistance in the presence of an applied electric current. Elimination or reduction of the resistance via immobilization of vortices is the "holy grail" of superconductivity research. Common wisdom dictates that an increase in the magnetic field escalates the loss of energy since the number of vortices increases. Here we show that this is no longer true if the magnetic field and the current are applied parallel to each other. Our experimental studies on the resistive behavior of a superconducting Mo0.79Ge0.21 nanostrip reveal the emergence of a dissipative state with increasing magnetic field, followed by a pronounced resistance drop, signifying a reentrance to the superconducting state. Large-scale simulations of the 3D time-dependent Ginzburg-Landau model indicate that the intermediate resistive state is due to an unwinding of twisted vortices. When the magnetic field increases, this instability is suppressed due to a better accommodation of the vortex lattice to the pinning configuration. Our findings show that magnetic field and geometrical confinement can suppress the dissipation induced by vortex motion and thus radically improve the performance of superconducting materials.

  4. Parallel magnetic field suppresses dissipation in superconducting nanostrips.

    Science.gov (United States)

    Wang, Yong-Lei; Glatz, Andreas; Kimmel, Gregory J; Aranson, Igor S; Thoutam, Laxman R; Xiao, Zhi-Li; Berdiyorov, Golibjon R; Peeters, François M; Crabtree, George W; Kwok, Wai-Kwong

    2017-11-28

    The motion of Abrikosov vortices in type-II superconductors results in a finite resistance in the presence of an applied electric current. Elimination or reduction of the resistance via immobilization of vortices is the "holy grail" of superconductivity research. Common wisdom dictates that an increase in the magnetic field escalates the loss of energy since the number of vortices increases. Here we show that this is no longer true if the magnetic field and the current are applied parallel to each other. Our experimental studies on the resistive behavior of a superconducting Mo 0.79 Ge 0.21 nanostrip reveal the emergence of a dissipative state with increasing magnetic field, followed by a pronounced resistance drop, signifying a reentrance to the superconducting state. Large-scale simulations of the 3D time-dependent Ginzburg-Landau model indicate that the intermediate resistive state is due to an unwinding of twisted vortices. When the magnetic field increases, this instability is suppressed due to a better accommodation of the vortex lattice to the pinning configuration. Our findings show that magnetic field and geometrical confinement can suppress the dissipation induced by vortex motion and thus radically improve the performance of superconducting materials.

  5. Behavioral activation and inhibition system's role in predicting addictive behaviors of patients with bipolar disorder of Roozbeh Psychiatric Hospital

    Directory of Open Access Journals (Sweden)

    Moslem Abbasi

    2016-01-01

    Conclusions: It can be said that the patients with bipolar disorder use substance and addictive behaviors for enjoyment and as pleasure stimulants; they also use substances to suppress unpleasant stimulants and negative emotions. These results indicate that behavioral activation and inhibition systems have an important role in the incidence and exacerbation of addictive behaviors. Therefore, preventive interventions in this direction seem to be necessary.

  6. Self Injurious Behavior in Adolescents

    Directory of Open Access Journals (Sweden)

    Evrim Aktepe

    2011-04-01

    Full Text Available Self injury is a kind of behavior which begins in early adolescence and difficult to determine because remains suppressed. Most often forms are to cut and hit own. To be exposed to sexual abuse and stressfully life events are known as risk factors for self injurious behavior. High anxiety, depression and hostility levels, decrease of self esteem, suicidal attempts and thoughts are usually together with self injurious behavior and it may be mediating to emotional regulation. To explain the functions of self injurious behavior automatic and social support theories and social learning theories have suggested. The relation between suicidality and self injurious behavior is complex for adolescents. There is no enough knowledge if self injurious behavior aggravates the risk of completed suicide. Although it’s a frequent behavior there are limited randomized controlled studies which examine specific treatment approaches. Dialectic behavior treatment is the type of treatment which shown as most effective for adults. To determine the needs to stop the behavior, to manage emotional senses and urges and to learn more healthy ways for needs to youth are necessary in treatment of self injurious behavior. Treatment also includes determining suicidal risk and comorbid psychiatric disorders. In self injurious behavior medical treatment is useful for comorbid psychiatric disorders. [TAF Prev Med Bull 2011; 10(2.000: 201-210

  7. Suppression Situations in Multiple Linear Regression

    Science.gov (United States)

    Shieh, Gwowen

    2006-01-01

    This article proposes alternative expressions for the two most prevailing definitions of suppression without resorting to the standardized regression modeling. The formulation provides a simple basis for the examination of their relationship. For the two-predictor regression, the author demonstrates that the previous results in the literature are…

  8. Cortisol suppresses radiation transformation in vitro

    International Nuclear Information System (INIS)

    Kennedy, A.R.

    1985-01-01

    It is reported that 10 -7 M cortisol has a significant suppressive effect on radiation-induced transformation in vitro in C3H10T 1/2 cells. Previously reported data showed a significant enhancing effect for similar experiments performed with cortisone. Thus, these two structurally similar glucocorticoid hormones have opposite effects on transformation induced by ionizing radiation. (author)

  9. Cooling device for reactor suppression pool

    International Nuclear Information System (INIS)

    Togasaki, Susumu; Kato, Kiyoshi.

    1994-01-01

    In a cooling device of a reactor suppression pool, when a temperature of pool water is abnormally increased and a heat absorbing portion is heated by, for example, occurrence of an accident, coolants are sent to the outside of the reactor container to actuates a thermally operating portion by the heat energy of coolants and drive heat exchanging fluids of a secondary cooling system. If the heat exchanging fluids are sent to a cooling portion, the coolants are cooled and returned to the heat absorbing portion of the suppression pool water. If the heat absorbing portion is heat pipes, the coolants are evaporated by heat absorbed from the suppression pool water, steams are sent to the thermally operating portion, then coolants are liquefied and caused to return to the heat absorbing portion. If the thermal operation portion is a gas turbine, the gas turbine is operated by the coolants, and it is converted to a rotational force to drive heat exchanging fluids by pumps. By constituting the cooling portion with a condensator, the coolants are condensed and liquefied and returned to the heat absorbing portion of the suppression pool water. (N.H.)

  10. Efflux inhibitor suppresses Streptococcus mutans virulence properties.

    Science.gov (United States)

    Zeng, Huihui; Liu, Jia; Ling, Junqi

    2017-04-01

    It is well established that efflux pumps play important roles in bacterial pathogenicity and efflux inhibitors (EIs) have been proved to be effective in suppressing bacterial virulence properties. However, little is known regarding the EI of Streptococcus mutans, a well-known caries-inducing bacterium. In this study, we identified the EI of S. mutans through ethidium bromide efflux assay and investigated how EI affected S. mutans virulence regarding the cariogenicity and stress response. Results indicated that reserpine, the identified EI, suppressed acid tolerance, mutacin production and transformation efficiency of S. mutans, and modified biofilm architecture and extracellular polysaccharide distribution. Suppressed glycosyltransferase activity was also noted after reserpine exposure. The data from quantitative real-time-PCR demonstrated that reserpine significantly altered the expression profile of quorum-sensing and virulence-associated genes. These findings suggest that reserpine represents a promising adjunct anticariogenic agent in that it suppresses virulence properties of S. mutans. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Measuring colour rivalry suppression in amblyopia.

    Science.gov (United States)

    Hofeldt, T S; Hofeldt, A J

    1999-11-01

    To determine if the colour rivalry suppression is an index of the visual impairment in amblyopia and if the stereopsis and fusion evaluator (SAFE) instrument is a reliable indicator of the difference in visual input from the two eyes. To test the accuracy of the SAFE instrument for measuring the visual input from the two eyes, colour rivalry suppression was measured in six normal subjects. A test neutral density filter (NDF) was placed before one eye to induce a temporary relative afferent defect and the subject selected the NDF before the fellow eye to neutralise the test NDF. In a non-paediatric private practice, 24 consecutive patients diagnosed with unilateral amblyopia were tested with the SAFE. Of the 24 amblyopes, 14 qualified for the study because they were able to fuse images and had no comorbid disease. The relation between depth of colour rivalry suppression, stereoacuity, and interocular difference in logMAR acuity was analysed. In normal subjects, the SAFE instrument reversed temporary defects of 0.3 to 1. 8 log units to within 0.6 log units. In amblyopes, the NDF to reverse colour rivalry suppression was positively related to interocular difference in logMAR acuity (beta=1.21, psuppression as measured with the SAFE was found to agree closely with the degree of visual acuity impairment in non-paediatric patients with amblyopia.

  12. Pressure suppression facility for reactor container

    International Nuclear Information System (INIS)

    Fujii, Tadashi; Fukui, Toru; Kataoka, Yoshiyuki; Tominaga, Kenji.

    1993-01-01

    In a nuclear reactor comprising heat transfer surfaces from a pressure suppression pool at the inside to the outer circumferential pool at the outside, a means for supplying water from a water supply source at the outside of the container to the pools is disposed. Then, a heat transfer means is disposed between the pressure suppression chamber and the water cooling pool. The water supply means comprises a pressurization means for applying pressure to water of the water supply source and a water supply channel. Water is supplied into the pressure suppression pool and the outer circumferential pool to elevate the water level and extend the region of heat contact with the water cooling heat transfer means. In addition, since dynamic pressure is applied to the feedwater, for example, by pressurizing the water surface of the water supply source, water can be supplied without using dynamic equipments such as pumps. Then, since water-cooling heat transfer surface can be extended after occurrence of accident, enlargement of a reactor container and worsening of earthquake proofness can be avoided as much as possible, to improve function for suppressing the pressure in the container. Further, since water-cooling heat transfer region can be extended, the arrangement of the water source and the place to which water is supplied is made optional without considering the relative height therebetween, to improve earthquake proofness. (N.H.)

  13. Quarkonium suppression: Gluonic dissociation vs. colour screening

    Indian Academy of Sciences (India)

    mechanism comes into play for the initial conditions taken from the self screened parton cascade model in these studies. Keywords. Quark gluon plasma; J ψ; suppression; dissociation; colour screening. PACS No. 12.38.M. 1. Introduction. The last two decades have seen hectic activity towards identifying unique signatures ...

  14. Aralia elata (Miquel) Seemann Suppresses Inflammatory ...

    African Journals Online (AJOL)

    ISSN: 1596-5996 (print); 1596-9827 (electronic) ... The LPS-induced increase in the production of nitric oxide was concentration- dependently suppressed ... Aralia elata ethanol extract (AEE) exhibits protective ... temperature for 72 h and filtered. The filtered .... scavenging activity in a dose-dependent manner showing a ...

  15. Time from HIV infection to virological suppression: dramatic fall from 2007 to 2016.

    Science.gov (United States)

    Medland, Nicholas A; Nicholson, Suellen; Chow, Eric P F; Read, Timothy R H; Bradshaw, Catriona S; Denham, Ian; Fairley, Christopher K

    2017-11-13

    Time from HIV infection to virological suppression: dramatic fall from 2007 to 2016. We examined the time from HIV infection to virological suppression in MSM who were first diagnosed at Melbourne Sexual Health Centre between 2007 and 2016. Retrospective cohort. Date of infection was imputed from the testing history or serological evidence of recent infection (negative or indeterminate western blot) or baseline CD4 cell count. Date of virological suppression was determined using clinical viral load data. We analysed predictors of diagnosis with serological evidence of recent infection (logistic regression) and time from diagnosis to suppression and from infection to suppression (Cox regression) using demographic, clinical, and behavioral covariates. Between 2007 and 2016, the median time from HIV infection to diagnosis fell from 6.8 to 4.3 months (P = 0.001), from diagnosis to suppression fell from 22.7 to 3.2 months (P < 0.0001), and from infection to suppression fell from 49.0 to 9.6 months (P < 0.0001). Serological evidence of recent infection increased from 15.6 to 34.3% (P < 0.0001) of diagnoses. In the multivariate analyses, age, being recently arrived from a non-English speaking country, history of IDU, other sexually transmitted infections, and sexual risk were not associated with any of these measures. The duration of infectiousness in MSM diagnosed with HIV infection at Melbourne Sexual Health Centre in Victoria has fallen dramatically between 2007 and 2016 and the proportion diagnosed with serological evidence of recent infection has increased. This effect is observed across all population subgroups and marks a positive milestone for the treatment as prevention paradigm.

  16. THE POPULATION IMPACT OF ELIMINATING HOMELESSNESS ON HIV VIRAL SUPPRESSION AMONG PEOPLE WHO USE DRUGS

    Science.gov (United States)

    Marshall, Brandon D.L.; Elston, Beth; Dobrer, Sabina; Parashar, Surita; Hogg, Robert S.; Montaner, Julio S.G.; Kerr, Thomas; Wood, Evan; Milloy, M-J

    2015-01-01

    Objective We sought to estimate the change in viral suppression prevalence if homelessness were eliminated from a population of HIV-infected people who use drugs (PWUD). Design Community-recruited prospective cohort of HIV-infected PWUD in Vancouver, Canada. Behavioral information was collected at baseline and linked to a province-wide HIV/AIDS treatment database. The primary outcome was viral suppression (<50 copies/mL) measured during subsequent routine clinical care. Methods We employed an imputation-based marginal modelling approach. First, we used modified Poisson regression to obtain effect estimates (adjusting for sociodemographics, substance use, addiction treatment, and other confounders). Then, we imputed an outcome probability for each individual while manipulating the exposure (homelessness). Population viral suppression prevalence under realized and “housed” scenarios were obtained by averaging these probabilities across the population. Bootstrapping was conducted to calculate 95% confidence limits. Results Of 706 individuals interviewed between January 2005 and December 2015, the majority was male (66.0%), of Caucasian race/ethnicity (55.1%), and had a history of injection (93.6%). At first study visit, 223 (31.6%) reported recent homelessness, and 37.8% were subsequently identified as virally suppressed. Adjusted marginal models estimated a 15.1% relative increase (95%CI: 9.0%, 21.7%) in viral suppression in the entire population—to 43.5% (95%CI: 39.4%, 48.2%)—if all homeless individuals were housed. Among those homeless, eliminating this exposure would increase viral suppression from 22.0% to 40.1% (95%CI: 35.1%, 46.1%), an 82.3% relative increase. Conclusions Interventions to house homeless, HIV-positive individuals who use drugs could significantly increase population viral suppression. Such interventions should be implemented as a part of renewed HIV/AIDS prevention and treatment efforts. PMID:26636924

  17. Theoretical status of J/ψ suppression

    International Nuclear Information System (INIS)

    Gavin, S.

    1993-03-01

    High energy heavy ion collisions are expected to produce hadron densities far beyond the density in nuclei, ρ 0 = 0.16 fm -3 . Remarkably, no single measurement from the AGS and SPS light ion programs with projectiles A ≤ 32 stands out as unambiguous evidence of these extreme densities. To separate the high density signals from the background effects that result, e.g. from scattering with primary nucleons, careful systematic studies of hadron-nucleus, hA, and nucleus-nucleus, AB, data are needed. In this talk the author surveys the ongoing systematic study of the most notorious case in point -- J/ψ suppression. In principle, measurements of J/ψ suppression provide a probe of the densities obtained in AB collisions that is also sensitive to quark gluon plasma production. The latest results from SPS experiment NA38 reported by A. Romana in these proceedings show that the ratio of cross sections in the dimuon channel B μμ σ ψ /σ cont is reduced by a factor 0.50 ± 0.05 in central S+U compared to minimum bias pU collisions at 200 AGeV. This is precisely the sort of suppression that one expects if high densities are obtained. On the other hand, a target-mass dependence suggestive of this suppression is found in hA collisions where high densities are not expected. At 200 GeV, NA38 finds that B μμ σ ψ /σ cont falls to 0.84 ± 0.08 in pU compared to pCu. The hA suppression in this kinematic regime is likely due to a combination of nuclear effects: nucleon absorption and shadowing

  18. Assessing fear following retrieval+extinction through suppression of baseline reward seeking vs. freezing

    Directory of Open Access Journals (Sweden)

    Jason eShumake

    2015-12-01

    Full Text Available Freezing has become the predominant measure used in rodent studies of conditioned fear, but conditioned suppression of reward-seeking behavior may provide a measure that is more relevant to human anxiety disorders; that is, a measure of how fear interferes with the enjoyment of pleasurable activities. Previous work has found that an isolated presentation of a fear conditioned stimulus prior to extinction training (retrieval + extinction results in a more robust and longer-lasting reduction in fear. The objective of this study was to assess whether the retrieval + extinction effect is evident using conditioned suppression of reward seeking, operationalized as a reduction in baseline licking (without prior water deprivation for a 10% sucrose solution. We found that, compared to freezing, conditioned suppression of reward seeking was much more sensitive to fear conditioning and far less responsive to extinction training. As in previous work, we found that retrieval + extinction reduced post-extinction fear reinstatement when measured as freezing, but it did not reduce fear reinstatement when measured as conditioned suppression. This suggests that there is still residual fear following retrieval + extinction, or that this procedure only modifies memory traces in neural circuits relevant to the expression of freezing, but not to the suppression of reward seeking.

  19. The Aversive Agent Lithium Chloride Suppresses Phasic Dopamine Release Through Central GLP-1 Receptors.

    Science.gov (United States)

    Fortin, Samantha M; Chartoff, Elena H; Roitman, Mitchell F

    2016-02-01

    Unconditioned rewarding stimuli evoke phasic increases in dopamine concentration in the nucleus accumbens (NAc) while discrete aversive stimuli elicit pauses in dopamine neuron firing and reductions in NAc dopamine concentration. The unconditioned effects of more prolonged aversive states on dopamine release dynamics are not well understood and are investigated here using the malaise-inducing agent lithium chloride (LiCl). We used fast-scan cyclic voltammetry to measure phasic increases in NAc dopamine resulting from electrical stimulation of dopamine cell bodies in the ventral tegmental area (VTA). Systemic LiCl injection reduced electrically evoked dopamine release in the NAc of both anesthetized and awake rats. As some behavioral effects of LiCl appear to be mediated through glucagon-like peptide-1 receptor (GLP-1R) activation, we hypothesized that the suppression of phasic dopamine by LiCl is GLP-1R dependent. Indeed, peripheral pretreatment with the GLP-1R antagonist exendin-9 (Ex-9) potently attenuated the LiCl-induced suppression of dopamine. Pretreatment with Ex-9 did not, however, affect the suppression of phasic dopamine release by the kappa-opioid receptor agonist, salvinorin A, supporting a selective effect of GLP-1R stimulation in LiCl-induced dopamine suppression. By delivering Ex-9 to either the lateral or fourth ventricle, we highlight a population of central GLP-1 receptors rostral to the hindbrain that are involved in the LiCl-mediated suppression of NAc dopamine release.

  20. Roles for miR-375 in Neuroendocrine Differentiation and Tumor Suppression via Notch Pathway Suppression in Merkel Cell Carcinoma.

    Science.gov (United States)

    Abraham, Karan J; Zhang, Xiao; Vidal, Ricardo; Paré, Geneviève C; Feilotter, Harriet E; Tron, Victor A

    2016-04-01

    Dysfunction of key miRNA pathways regulating basic cellular processes is a common driver of many cancers. However, the biological roles and/or clinical applications of such pathways in Merkel cell carcinoma (MCC), a rare but lethal cutaneous neuroendocrine (NE) malignancy, have yet to be determined. Previous work has established that miR-375 is highly expressed in MCC tumors, but its biological role in MCC remains unknown. Herein, we show that elevated miR-375 expression is a specific feature of well-differentiated MCC cell lines that express NE markers. In contrast, miR-375 is strikingly down-regulated in highly aggressive, undifferentiated MCC cell lines. Enforced miR-375 expression in these cells induced NE differentiation, and opposed cancer cell viability, migration, invasion, and survival, pointing to tumor-suppressive roles for miR-375. Mechanistically, miR-375-driven phenotypes were caused by the direct post-transcriptional repression of multiple Notch pathway proteins (Notch2 and RBPJ) linked to cancer and regulation of cell fate. Thus, we detail a novel molecular axis linking tumor-suppressive miR-375 and Notch with NE differentiation and cancer cell behavior in MCC. Our findings identify miR-375 as a putative regulator of NE differentiation, provide insight into the cell of origin of MCC, and suggest that miR-375 silencing may promote aggressive cancer cell behavior through Notch disinhibition. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  1. Dietary Sodium Suppresses Digestive Efficiency via the Renin-Angiotensin System.

    Science.gov (United States)

    Weidemann, Benjamin J; Voong, Susan; Morales-Santiago, Fabiola I; Kahn, Michael Z; Ni, Jonathan; Littlejohn, Nicole K; Claflin, Kristin E; Burnett, Colin M L; Pearson, Nicole A; Lutter, Michael L; Grobe, Justin L

    2015-06-11

    Dietary fats and sodium are both palatable and are hypothesized to synergistically contribute to ingestive behavior and thereby obesity. Contrary to this hypothesis, C57BL/6J mice fed a 45% high fat diet exhibited weight gain that was inhibited by increased dietary sodium content. This suppressive effect of dietary sodium upon weight gain was mediated specifically through a reduction in digestive efficiency, with no effects on food intake behavior, physical activity, or resting metabolism. Replacement of circulating angiotensin II levels reversed the effects of high dietary sodium to suppress digestive efficiency. While the AT1 receptor antagonist losartan had no effect in mice fed low sodium, the AT2 receptor antagonist PD-123,319 suppressed digestive efficiency. Correspondingly, genetic deletion of the AT2 receptor in FVB/NCrl mice resulted in suppressed digestive efficiency even on a standard chow diet. Together these data underscore the importance of digestive efficiency in the pathogenesis of obesity, and implicate dietary sodium, the renin-angiotensin system, and the AT2 receptor in the control of digestive efficiency regardless of mouse strain or macronutrient composition of the diet. These findings highlight the need for greater understanding of nutrient absorption control physiology, and prompt more uniform assessment of digestive efficiency in animal studies of energy balance.

  2. Suppressed visual looming stimuli are not integrated with auditory looming signals: Evidence from continuous flash suppression.

    Science.gov (United States)

    Moors, Pieter; Huygelier, Hanne; Wagemans, Johan; de-Wit, Lee; van Ee, Raymond

    2015-01-01

    Previous studies using binocular rivalry have shown that signals in a modality other than the visual can bias dominance durations depending on their congruency with the rivaling stimuli. More recently, studies using continuous flash suppression (CFS) have reported that multisensory integration influences how long visual stimuli remain suppressed. In this study, using CFS, we examined whether the contrast thresholds for detecting visual looming stimuli are influenced by a congruent auditory stimulus. In Experiment 1, we show that a looming visual stimulus can result in lower detection thresholds compared to a static concentric grating, but that auditory tone pips congruent with the looming stimulus did not lower suppression thresholds any further. In Experiments 2, 3, and 4, we again observed no advantage for congruent multisensory stimuli. These results add to our understanding of the conditions under which multisensory integration is possible, and suggest that certain forms of multisensory integration are not evident when the visual stimulus is suppressed from awareness using CFS.

  3. Benchmark enclosure fire suppression experiments - phase 1 test report.

    Energy Technology Data Exchange (ETDEWEB)

    Figueroa, Victor G.; Nichols, Robert Thomas; Blanchat, Thomas K.

    2007-06-01

    A series of fire benchmark water suppression tests were performed that may provide guidance for dispersal systems for the protection of high value assets. The test results provide boundary and temporal data necessary for water spray suppression model development and validation. A review of fire suppression in presented for both gaseous suppression and water mist fire suppression. The experimental setup and procedure for gathering water suppression performance data are shown. Characteristics of the nozzles used in the testing are presented. Results of the experiments are discussed.

  4. [The advances of suppression in research of amblyopia].

    Science.gov (United States)

    Liu, S; Liu, H

    2016-04-11

    Suppression that is the result of interocular competition is an important machanism of amblyopia. The imbalance of suppression may lead the consequence to amblyopia. In the early study, researchers had raised the theory of II. Quadratic Summation which had revealed the relationship of interocular interaction and suppression. In some basic researches, other studies had showed the most possible anatomic location of suppression. Recently, researchers found a new method to quantify the interocular suppression named the noise model. Further studies found a novel disinhibition therapy to treat amblyopia. We summarized the research advances in suppression and disinhibition treatment in amblyopia. (Chin J Ophthalmol, 2016, 52: 305-308).

  5. Factor structure and clinical correlates of the Food Thought Suppression Inventory within treatment seeking obese women with binge eating disorder.

    Science.gov (United States)

    Barnes, Rachel D; Sawaoka, Takuya; White, Marney A; Masheb, Robin M; Grilo, Carlos M

    2013-01-01

    Prior research on the relations among eating behaviors and thought suppression is limited to a measure of general thought suppression, the White Bear Suppression Inventory. To address this limitation, researchers recently validated the Food Thought Suppression Inventory (FTSI). Analyses using this measure suggest that food thought suppression is distinct from and is more predictive of eating disorder psychopathology than is general thought suppression. The FTSI, however, has not yet been validated in clinical samples. The purpose of the current study is to examine the factor structure and clinical correlates of the FTSI within treatment seeking obese women with binge eating disorder (BED; N=128). Analyses revealed a valid and reliable one-factor measure of food thought suppression that was related to higher levels of eating and general psychopathology. The findings provide evidence for the use of the FTSI with obese women with BED. Future research should examine the psychometric properties of the FTSI within larger and more diverse samples. Copyright © 2012. Published by Elsevier Ltd.

  6. Proton density-weighted MR imaging of the knee: fat suppression versus without fat suppression

    International Nuclear Information System (INIS)

    Lee, So-Yeon; Kim, Sun Ki; Jee, Won-Hee; Kim, Jung-Man

    2011-01-01

    To prospectively evaluate the diagnostic accuracy of proton density-weighted imaging with and without fat suppression for detecting meniscal tears. The study involved 48 patients who underwent arthroscopy less than 3 months after proton density-weighted imaging with and without fat suppression. Sagittal images were independently reviewed by two radiologists for the presence of meniscal tears. Medial and lateral menisci were separately analyzed in terms of anterior horn, body, and posterior horn. Interobserver agreement was assessed using κ coefficients. The McNemar test was used to determine any differences between the two methods in terms of sensitivity and specificity. Arthroscopy findings were used as the diagnostic reference standard. Arthroscopy revealed 71 tears involving 85 meniscal segments: 34 medial meniscal segments and 51 lateral meniscal segments. The sensitivity, specificity, and accuracy of each radiologist were 95% (81/85), 92% (186/203), and 93% (267/288), and 93% (79/85), 93% (189/203), and 93% (268/288) when using fat-suppressed proton density-weighted imaging, and 91% (77/85), 93% (189/203), and 92% (266/288), and 91% (77/85), 93% (188/203), and 92% (265/288) when using proton density-weighted imaging without fat suppression, respectively. Interobserver agreement for meniscal tears was very high with proton-weighted imaging with (κ = 0.87) or without (κ = 0.86) fat suppression. There were no significant differences for detection of medial meniscal tears when using proton density-weighted imaging with or without fat suppression for both readers (p > 0.05). Fat-suppressed proton density-weighted imaging can replace proton density-weighted imaging without fat suppression for the detection of meniscal tears. (orig.)

  7. Proton density-weighted MR imaging of the knee: fat suppression versus without fat suppression

    Energy Technology Data Exchange (ETDEWEB)

    Lee, So-Yeon; Kim, Sun Ki [Catholic University of Korea, Department of Radiology, Seoul St. Mary' s Hospital, Seoul (Korea, Republic of); Jee, Won-Hee [Catholic University of Korea, Department of Radiology, Seoul St. Mary' s Hospital, Seoul (Korea, Republic of); Catholic University of Korea, Diagnostic Radiology, Seoul St. Mary' s Hospital, School of Medicine, Seoul (Korea, Republic of); Kim, Jung-Man [Catholic University of Korea, Department of Orthopedic Surgery, Seoul St. Mary' s Hospital, Seoul (Korea, Republic of)

    2011-02-15

    To prospectively evaluate the diagnostic accuracy of proton density-weighted imaging with and without fat suppression for detecting meniscal tears. The study involved 48 patients who underwent arthroscopy less than 3 months after proton density-weighted imaging with and without fat suppression. Sagittal images were independently reviewed by two radiologists for the presence of meniscal tears. Medial and lateral menisci were separately analyzed in terms of anterior horn, body, and posterior horn. Interobserver agreement was assessed using {kappa} coefficients. The McNemar test was used to determine any differences between the two methods in terms of sensitivity and specificity. Arthroscopy findings were used as the diagnostic reference standard. Arthroscopy revealed 71 tears involving 85 meniscal segments: 34 medial meniscal segments and 51 lateral meniscal segments. The sensitivity, specificity, and accuracy of each radiologist were 95% (81/85), 92% (186/203), and 93% (267/288), and 93% (79/85), 93% (189/203), and 93% (268/288) when using fat-suppressed proton density-weighted imaging, and 91% (77/85), 93% (189/203), and 92% (266/288), and 91% (77/85), 93% (188/203), and 92% (265/288) when using proton density-weighted imaging without fat suppression, respectively. Interobserver agreement for meniscal tears was very high with proton-weighted imaging with ({kappa} = 0.87) or without ({kappa} = 0.86) fat suppression. There were no significant differences for detection of medial meniscal tears when using proton density-weighted imaging with or without fat suppression for both readers (p > 0.05). Fat-suppressed proton density-weighted imaging can replace proton density-weighted imaging without fat suppression for the detection of meniscal tears. (orig.)

  8. Modeling and analysis of friction clutch at a driveline for suppressing car starting judder

    Science.gov (United States)

    Li, Liping; Lu, Zhaijun; Liu, Xue-Lai; Sun, Tao; Jing, Xingjian; Shangguan, Wen-Bin

    2018-06-01

    Car judder is a kind of back-forth vibration during vehicle starting which caused by the torsional oscillation of the driveline. This paper presents a systematic study on the dynamic response characteristics of the clutch driven disc for suppression of the judder during vehicle starting. Self-excited vibration behavior of the clutch driven disc is analyzed based on the developed 4DOF non-linear multi-body dynamic model of the clutch driving process considering stick-slip characteristics and using Karnopp friction models. Physical parameters of a clutch determining the generations of the judder behaviors are discussed and the revised designs of the driven disc of a clutch for suppression of the judder are consequently investigated and validated with experiments for two real cars.

  9. Metacognition in addictive behaviors.

    Science.gov (United States)

    Spada, Marcantonio M; Caselli, Gabriele; Nikčević, Ana V; Wells, Adrian

    2015-05-01

    Over the last twenty years metacognitive theory has provided a novel framework, in the form of the Self-Regulatory Executive Function (S-REF) model, for conceptualizing psychological distress (Wells & Matthews, 1994, 1996). The S-REF model proposes that psychological distress persists because of unhelpful coping styles (e.g. extended thinking and thought suppression) which are activated and maintained as a result of metacognitive beliefs. This paper describes the S-REF model and its application to addictive behaviors using a triphasic metacognitive formulation. Evidence on the components of the triphasic metacognitive formulation is reviewed and the clinical implications for applying metacognitive therapy to addictive behaviors outlined. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. AgRP Neurons Can Increase Food Intake during Conditions of Appetite Suppression and Inhibit Anorexigenic Parabrachial Neurons.

    Science.gov (United States)

    Essner, Rachel A; Smith, Alison G; Jamnik, Adam A; Ryba, Anna R; Trutner, Zoe D; Carter, Matthew E

    2017-09-06

    To maintain energy homeostasis, orexigenic (appetite-inducing) and anorexigenic (appetite suppressing) brain systems functionally interact to regulate food intake. Within the hypothalamus, neurons that express agouti-related protein (AgRP) sense orexigenic factors and orchestrate an increase in food-seeking behavior. In contrast, calcitonin gene-related peptide (CGRP)-expressing neurons in the parabrachial nucleus (PBN) suppress feeding. PBN CGRP neurons become active in response to anorexigenic hormones released following a meal, including amylin, secreted by the pancreas, and cholecystokinin (CCK), secreted by the small intestine. Additionally, exogenous compounds, such as lithium chloride (LiCl), a salt that creates gastric discomfort, and lipopolysaccharide (LPS), a bacterial cell wall component that induces inflammation, exert appetite-suppressing effects and activate PBN CGRP neurons. The effects of increasing the homeostatic drive to eat on feeding behavior during appetite suppressing conditions are unknown. Here, we show in mice that food deprivation or optogenetic activation of AgRP neurons induces feeding to overcome the appetite suppressing effects of amylin, CCK, and LiCl, but not LPS. AgRP neuron photostimulation can also increase feeding during chemogenetic-mediated stimulation of PBN CGRP neurons. AgRP neuron stimulation reduces Fos expression in PBN CGRP neurons across all conditions. Finally, stimulation of projections from AgRP neurons to the PBN increases feeding following administration of amylin, CCK, and LiCl, but not LPS. These results demonstrate that AgRP neurons are sufficient to increase feeding during noninflammatory-based appetite suppression and to decrease activity in anorexigenic PBN CGRP neurons, thereby increasing food intake during homeostatic need. SIGNIFICANCE STATEMENT The motivation to eat depends on the relative balance of activity in distinct brain regions that induce or suppress appetite. An abnormal amount of activity in

  11. A Compton-suppressed spectrometer for studies of chaos in nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Shriner, J.F. Jr. [Tennessee Technological Univ., Cookeville (United States); Bilpuch, E.G. [Duke University Press, Durham, NC (United States); Bybee, C.R. [Triangle Universities Nuclear Lab., Durham, NC (United States); Mitchell, G.E. [Triangle Universities Nuclear Lab., Durham, NC (United States); Moore, E.F. [Triangle Universities Nuclear Lab., Durham, NC (United States); Shriner, J.D. [Triangle Universities Nuclear Lab., Durham, NC (United States); Westerfeldt, C.R. [Duke University Press, Durham, NC (United States)

    1995-05-01

    One approach to studying chaos in quantum systems utilizes the statistical behavior of eigenvalues. Such analyses require data of very high quality, since both completeness and purity are essential. The design of a Compton-suppressed {gamma}-ray spectrometer for the purpose of establishing a nearly complete level scheme in {sup 30}P via the {sup 29}Si(p, {gamma}) reaction is described. Design criteria and implementation are discussed, and early results from the system are presented. (orig.).

  12. Overcoming fixation with repeated memory suppression.

    Science.gov (United States)

    Angello, Genna; Storm, Benjamin C; Smith, Steven M

    2015-01-01

    Fixation (blocks to memories or ideas) can be alleviated not only by encouraging productive work towards a solution, but, as the present experiments show, by reducing counterproductive work. Two experiments examined relief from fixation in a word-fragment completion task. Blockers, orthographically similar negative primes (e.g., ANALOGY), blocked solutions to word fragments (e.g., A_L_ _GY) in both experiments. After priming, but before the fragment completion test, participants repeatedly suppressed half of the blockers using the Think/No-Think paradigm, which results in memory inhibition. Inhibiting blockers did not alleviate fixation in Experiment 1 when conscious recollection of negative primes was not encouraged on the fragment completion test. In Experiment 2, however, when participants were encouraged to remember negative primes at fragment completion, relief from fixation was observed. Repeated suppression may nullify fixation effects, and promote creative thinking, particularly when fixation is caused by conscious recollection of counterproductive information.

  13. Magnetic fusion development for global warming suppression

    International Nuclear Information System (INIS)

    Li Jiangang; Zhang Jie; Duan Xuru

    2010-01-01

    Energy shortage and environmental pollution are two critical issues for human beings in the 21st century. There is an urgent need for new sustainable energy to meet the fast growing demand for clean energy. Fusion is one of the few options which may be able to satisfy the requirement for large scale sustainable energy generation and global warming suppression and therefore must be developed as quickly as possible. Fusion research has been carried out for the past 50 years. It is too long to wait for another 50 years to generate electricity by fusion. A much more aggressive approach should be taken with international collaboration towards the early use of fusion energy to meet the urgent needs for energy and global warming suppression.

  14. Suppression of Rabi oscillations for moving atoms

    International Nuclear Information System (INIS)

    Navarro, B.; Egusquiza, I. L.; Muga, J. G.; Hegerfeldt, G. C.

    2003-01-01

    The well-known laser-induced Rabi oscillations of a two-level atom are shown to be suppressed under certain conditions when the atom is entering a laser-illuminated region. For temporal Rabi oscillations the effect has two regimes: a first classical-like one, taking place at intermediate atomic velocities, and a second purely quantum case at low velocities. The classical regime is associated with the formation of incoherent internal states of the atom in the laser region, whereas in the quantum, low velocity regime the laser projects the atom onto a pure internal state that can be controlled by detuning. Spatial Rabi oscillations are only suppressed in this low velocity, quantum regime

  15. Suppression of Poxvirus Replication by Resveratrol.

    Science.gov (United States)

    Cao, Shuai; Realegeno, Susan; Pant, Anil; Satheshkumar, Panayampalli S; Yang, Zhilong

    2017-01-01

    Poxviruses continue to cause serious diseases even after eradication of the historically deadly infectious human disease, smallpox. Poxviruses are currently being developed as vaccine vectors and cancer therapeutic agents. Resveratrol is a natural polyphenol stilbenoid found in plants that has been shown to inhibit or enhance replication of a number of viruses, but the effect of resveratrol on poxvirus replication is unknown. In the present study, we found that resveratrol dramatically suppressed the replication of vaccinia virus (VACV), the prototypic member of poxviruses, in various cell types. Resveratrol also significantly reduced the replication of monkeypox virus, a zoonotic virus that is endemic in Western and Central Africa and causes human mortality. The inhibitory effect of resveratrol on poxviruses is independent of VACV N1 protein, a potential resveratrol binding target. Further experiments demonstrated that resveratrol had little effect on VACV early gene expression, while it suppressed VACV DNA synthesis, and subsequently post-replicative gene expression.

  16. Suppression of Poxvirus Replication by Resveratrol

    Directory of Open Access Journals (Sweden)

    Shuai Cao

    2017-11-01

    Full Text Available Poxviruses continue to cause serious diseases even after eradication of the historically deadly infectious human disease, smallpox. Poxviruses are currently being developed as vaccine vectors and cancer therapeutic agents. Resveratrol is a natural polyphenol stilbenoid found in plants that has been shown to inhibit or enhance replication of a number of viruses, but the effect of resveratrol on poxvirus replication is unknown. In the present study, we found that resveratrol dramatically suppressed the replication of vaccinia virus (VACV, the prototypic member of poxviruses, in various cell types. Resveratrol also significantly reduced the replication of monkeypox virus, a zoonotic virus that is endemic in Western and Central Africa and causes human mortality. The inhibitory effect of resveratrol on poxviruses is independent of VACV N1 protein, a potential resveratrol binding target. Further experiments demonstrated that resveratrol had little effect on VACV early gene expression, while it suppressed VACV DNA synthesis, and subsequently post-replicative gene expression.

  17. Managing for soil health can suppress pests

    Directory of Open Access Journals (Sweden)

    Amanda Hodson

    2016-08-01

    Full Text Available A “healthy” soil can be thought of as one that functions well, both agronomically and ecologically, and one in which soil biodiversity and crop management work in synergy to suppress pests and diseases. UC researchers have pioneered many ways of managing soil biology for pest management, including strategies such as soil solarization, steam treatment and anaerobic soil disinfestation, as well as improvements on traditional methods, such as reducing tillage, amending soil with organic materials, and cover cropping. As managing for soil health becomes more of an explicit focus due to restrictions on the use of soil fumigants, integrated soil health tests will be needed that are validated for use in California. Other research needs include breeding crops for disease resistance and pest suppressive microbial communities as well as knowledge of how beneficial organisms influence plant health.

  18. Prevention and suppression of metal packing fires.

    Science.gov (United States)

    Roberts, Mark; Rogers, William J; Sam Mannan, M; Ostrowski, Scott W

    2003-11-14

    Structured packing has been widely used because of large surface area that makes possible columns with high capacity and efficiency. The large surface area also contributes to fire hazards because of hydrocarbon deposits that can easily combust and promote combustion of the thin metal packing materials. Materials of high surface area that can fuel fires include reactive metals, such as titanium, and materials that are not considered combustible, such as stainless steel. Column design and material selection for packing construction is discussed together with employee training and practices for safe column maintenance and operations. Presented also are methods and agents for suppression of metal fires. Guidance for prevention and suppression of metal fires is related to incidents involving packing fires in columns.

  19. Compton suppression through rise-time analysis

    International Nuclear Information System (INIS)

    Selvi, S.; Celiktas, C.

    2007-01-01

    We studied Compton suppression for 60 Co and 137 Cs radioisotopes using a signal selection criterion based on contrasting the fall time of the signals composing the photo peak with those composing the Compton continuum. The fall time criterion is employed by using the pulse shape analysis observing the change in the fall times of the gamma-ray pulses. This change is determined by measuring the changes in the rise times related to the fall time of the scintillator and the timing signals related to the fall time of the input signals. We showed that Compton continuum suppression is achieved best via the precise timing adjustment of an analog rise-time analyzer connected to a NaI(Tl) scintillation spectrometer

  20. Abnormal Grain Growth Suppression in Aluminum Alloys

    Science.gov (United States)

    Hales, Stephen J. (Inventor); Claytor, Harold Dale (Inventor); Alexa, Joel A. (Inventor)

    2015-01-01

    The present invention provides a process for suppressing abnormal grain growth in friction stir welded aluminum alloys by inserting an intermediate annealing treatment ("IAT") after the welding step on the article. The IAT may be followed by a solution heat treatment (SHT) on the article under effectively high solution heat treatment conditions. In at least some embodiments, a deformation step is conducted on the article under effective spin-forming deformation conditions or under effective superplastic deformation conditions. The invention further provides a welded article having suppressed abnormal grain growth, prepared by the process above. Preferably the article is characterized with greater than about 90% reduction in area fraction abnormal grain growth in any friction-stir-welded nugget.

  1. Pressure suppression device for a reactor container

    International Nuclear Information System (INIS)

    Shimizu, Toshiaki

    1982-01-01

    Purpose: To prevent damages in drain pipes or the likes upon the water level increase due to blowing of incompressible gases. Constitution: An exhaust pipe for guiding escaping steams is connected to a main steam releaf valve. The exhaust pipe is guided into pressure-suppression-chamber water through the inside of a dry-well and by way of a vent pipe, a vent header and a drain pipe or a downcomer. Since the exhaust pipe is not exposed to the water surface inside the pressure suppression chamber, even if steams blow out into the dry-well by the rapture of pipeways or the likes to rapidly increase the water level, the water surface does not hit on the exhaust pipe, whereby the damages for the exhaust pipe and support members can be prevented to improve the reliability. (Seki, T.)

  2. Testing tic suppression: comparing the effects of dexmethylphenidate to no medication in children and adolescents with attention-deficit/hyperactivity disorder and Tourette's disorder.

    Science.gov (United States)

    Lyon, Gholson J; Samar, Stephanie M; Conelea, Christine; Trujillo, Marcel R; Lipinski, Christina M; Bauer, Christopher C; Brandt, Bryan C; Kemp, Joshua J; Lawrence, Zoe E; Howard, Jonathan; Castellanos, F Xavier; Woods, Douglas; Coffey, Barbara J

    2010-08-01

    The aim of this study was to conduct a pilot study testing whether single-dose, immediate-release dexmethylphenidate (dMPH) can facilitate tic suppression in children and adolescents with attention-deficit/hyperactivity disorder (ADHD) and Tourette's disorder (TD) or chronic tic disorders. The primary hypothesis is that dMPH will improve behaviorally reinforced tic suppression in a standard tic suppression paradigm (TSP). Ten children with ADHD and TD were given dMPH on one visit and no medication on another, using a random crossover design. On both days, following a baseline period, subjects were reinforced for suppressing tics using a standard TSP. Thirteen subjects were enrolled; 10 subjects (mean age 12.7 +/- 2.6; 90% male) completed all study procedures. Relative to the no-medication condition, tics were reduced when children were given a single dose of dMPH. Behavioral reinforcement of tic suppression resulted in lower rates of tics compared to baseline, but dMPH did not enhance this suppression. Preliminary results indicate replication of prior studies of behavioral tic suppression in youths with TD and without ADHD. In addition, our findings indicate tic reduction (and not tic exacerbation) with acute dMPH challenge in children and adolescents with ADHD and TD.

  3. Myc suppression of Nfkb2 accelerates lymphomagenesis

    International Nuclear Information System (INIS)

    Keller, Ulrich; Huber, Jürgen; Nilsson, Jonas A; Fallahi, Mohammad; Hall, Mark A; Peschel, Christian; Cleveland, John L

    2010-01-01

    Deregulated c-Myc expression is a hallmark of several human cancers where it promotes proliferation and an aggressive tumour phenotype. Myc overexpression is associated with reduced activity of Rel/NF-κB, transcription factors that control the immune response, cell survival, and transformation, and that are frequently altered in cancer. The Rel/NF-κB family member NFKB2 is altered by chromosomal translocations or deletions in lymphoid malignancies and deletion of the C-terminal ankyrin domain of NF-κB2 augments lymphocyte proliferation. Precancerous Eμ-Myc-transgenic B cells, Eμ-Myc lymphomas and human Burkitt lymphoma samples were assessed for Nfkb2 expression. The contribution of Nfkb2 to Myc-driven apoptosis, proliferation, and lymphomagenesis was tested genetically in vivo. Here we report that the Myc oncoprotein suppresses Nfkb2 expression in vitro in primary mouse fibroblasts and B cells, and in vivo in the Eμ-Myc transgenic mouse model of human Burkitt lymphoma (BL). NFKB2 suppression by Myc was also confirmed in primary human BL. Promoter-reporter assays indicate that Myc-mediated suppression of Nfkb2 occurs at the level of transcription. The contribution of Nfkb2 to Myc-driven lymphomagenesis was tested in vivo, where Nfkb2 loss was shown to accelerate lymphoma development in Eμ-Myc transgenic mice, by impairing Myc's apoptotic response. Nfkb2 is suppressed by c-Myc and harnesses Myc-driven lymphomagenesis. These data thus link Myc-driven lymphomagenesis to the non-canonical NF-κB pathway

  4. Hangar Fire Suppression Utilizing Novec 1230

    Science.gov (United States)

    2018-01-01

    fuel fires in aircraft hangars. A 30×30×8-ft concrete-and-steel test structure was constructed for this test series. Four discharge assemblies...that agent concentration in the test structure exceeded the required extinguishing concentration for at least 5 min after discharge. Two fire ...involved suppression of a 4.6-gal, approximately 5-ft diameter, Jet-A pool fire . Both fires were successfully extinguished by the Novec 1230 discharge

  5. Thought Suppression in Patients With Bipolar Disorder

    OpenAIRE

    Miklowitz, David J.; Alatiq, Yousra; Geddes, John R.; Goodwin, Guy M.; Williams, J. Mark G.

    2010-01-01

    Suppression of negative thoughts has been observed under experimental conditions among patients with major depressive disorder (MDD) but has never been examined among patients with bipolar disorder (BD). Patients with BD (n = 36), patients with MDD (n = 20), and healthy controls (n = 20) completed a task that required unscrambling 6-word strings into 5-word sentences, leaving out 1 word. The extra word allowed the sentences to be completed in a negative, neutral, or ?hyperpositive? (manic/goa...

  6. Mechanisms underlying UV-induced immune suppression

    International Nuclear Information System (INIS)

    Ullrich, Stephen E.

    2005-01-01

    Skin cancer is the most prevalent form of human neoplasia. Estimates suggest that in excess of one million new cases of skin cancer will be diagnosed this year alone in the United States (www.cancer.org/statistics). Fortunately, because of their highly visible location, skin cancers are more rapidly diagnosed and more easily treated than other types of cancer. Be that as it may, approximately 10,000 Americans a year die from skin cancer. The cost of treating non-melanoma skin cancer is estimated to be in excess of US$ 650 million a year [J.G. Chen, A.B. Fleischer, E.D. Smith, C. Kancler, N.D. Goldman, P.M. Williford, S.R. Feldman, Cost of non-melanoma skin cancer treatment in the United States, Dermatol. Surg. 27 (2001) 1035-1038], and when melanoma is included, the estimated cost of treating skin cancer in the United States is estimated to rise to US$ 2.9 billion annually (www.cancer.org/statistics). Because the morbidity and mortality associated with skin cancer is a major public health problem, it is important to understand the mechanisms underlying skin cancer development. The primary cause of skin cancer is the ultraviolet (UV) radiation found in sunlight. In addition to its carcinogenic potential, UV radiation is also immune suppressive. In fact, data from studies with both experimental animals and biopsy proven skin cancer patients suggest that there is an association between the immune suppressive effects of UV radiation and its carcinogenic potential. The focus of this manuscript will be to review the mechanisms underlying the induction of immune suppression following UV exposure. Particular attention will be directed to the role of soluble mediators in activating immune suppression

  7. Suppression of radiation excitation in focusing environment

    International Nuclear Information System (INIS)

    Huang, Z.; Ruth, R.D.

    1996-12-01

    Radiation damping and quantum excitation in an electron damping ring and a straight focusing channel are reviewed. They are found to be the two limiting cases in the study of a general bending and focusing combined system. In the intermediate regime where the radiation formation length is comparable to the betatron wavelength, quantum excitation can be exponentially suppressed by focusing field. This new regime may have interesting applications in the generation of ultra-low emittance beams

  8. Focal Suppression of Distractor Sounds by Selective Attention in Auditory Cortex.

    Science.gov (United States)

    Schwartz, Zachary P; David, Stephen V

    2018-01-01

    Auditory selective attention is required for parsing crowded acoustic environments, but cortical systems mediating the influence of behavioral state on auditory perception are not well characterized. Previous neurophysiological studies suggest that attention produces a general enhancement of neural responses to important target sounds versus irrelevant distractors. However, behavioral studies suggest that in the presence of masking noise, attention provides a focal suppression of distractors that compete with targets. Here, we compared effects of attention on cortical responses to masking versus non-masking distractors, controlling for effects of listening effort and general task engagement. We recorded single-unit activity from primary auditory cortex (A1) of ferrets during behavior and found that selective attention decreased responses to distractors masking targets in the same spectral band, compared with spectrally distinct distractors. This suppression enhanced neural target detection thresholds, suggesting that limited attention resources serve to focally suppress responses to distractors that interfere with target detection. Changing effort by manipulating target salience consistently modulated spontaneous but not evoked activity. Task engagement and changing effort tended to affect the same neurons, while attention affected an independent population, suggesting that distinct feedback circuits mediate effects of attention and effort in A1. © The Author 2017. Published by Oxford University Press.

  9. Suppressing bullfrog larvae with carbon dioxide

    Science.gov (United States)

    Gross, Jackson A.; Ray, Andrew; Sepulveda, Adam J.; Watten, Barnaby J.; Densmore, Christine L.; Layhee, Megan J.; Mark Abbey-Lambert,; ,

    2014-01-01

    Current management strategies for the control and suppression of the American Bullfrog (Lithobates catesbeianus = Rana catesbeiana Shaw) and other invasive amphibians have had minimal effect on their abundance and distribution. This study evaluates the effects of carbon dioxide (CO2) on pre- and prometamorphic Bullfrog larvae. Bullfrogs are a model organism for evaluating potential suppression agents because they are a successful invader worldwide. From experimental trials we estimated that the 24-h 50% and 99% lethal concentration (LC50 and LC99) values for Bullfrog larvae were 371 and 549 mg CO2/L, respectively. Overall, larvae that succumbed to experimental conditions had a lower body condition index than those that survived. We also documented sublethal changes in blood chemistry during prolonged exposure to elevated CO2. Specifically, blood pH decreased by more than 0.5 pH units after 9 h of exposure and both blood partial pressure of CO2 (pCO2) and blood glucose increased. These findings suggest that CO2 treatments can be lethal to Bullfrog larvae under controlled laboratory conditions. We believe this work represents the necessary foundation for further consideration of CO2 as a potential suppression agent for one of the most harmful invaders to freshwater ecosystems.

  10. Subjective duration distortions mirror neural repetition suppression.

    Science.gov (United States)

    Pariyadath, Vani; Eagleman, David M

    2012-01-01

    Subjective duration is strongly influenced by repetition and novelty, such that an oddball stimulus in a stream of repeated stimuli appears to last longer in duration in comparison. We hypothesize that this duration illusion, called the temporal oddball effect, is a result of the difference in expectation between the oddball and the repeated stimuli. Specifically, we conjecture that the repeated stimuli contract in duration as a result of increased predictability; these duration contractions, we suggest, result from decreased neural response amplitude with repetition, known as repetition suppression. Participants viewed trials consisting of lines presented at a particular orientation (standard stimuli) followed by a line presented at a different orientation (oddball stimulus). We found that the size of the oddball effect correlates with the number of repetitions of the standard stimulus as well as the amount of deviance from the oddball stimulus; both of these results are consistent with a repetition suppression hypothesis. Further, we find that the temporal oddball effect is sensitive to experimental context--that is, the size of the oddball effect for a particular experimental trial is influenced by the range of duration distortions seen in preceding trials. Our data suggest that the repetition-related duration contractions causing the oddball effect are a result of neural repetition suppression. More generally, subjective duration may reflect the prediction error associated with a stimulus and, consequently, the efficiency of encoding that stimulus. Additionally, we emphasize that experimental context effects need to be taken into consideration when designing duration-related tasks.

  11. Variation in plant defense suppresses herbivore performance

    Science.gov (United States)

    Pearse, Ian; Paul, Ryan; Ode, Paul J.

    2018-01-01

    Defensive variability of crops and natural systems can alter herbivore communities and reduce herbivory. However, it is still unknown how defense variability translates into herbivore suppression. Nonlinear averaging and constraints in physiological tracking (also more generally called time-dependent effects) are the two mechanisms by which defense variability might impact herbivores. We conducted a set of experiments manipulating the mean and variability of a plant defense, showing that defense variability does suppress herbivore performance and that it does so through physiological tracking effects that cannot be explained by nonlinear averaging. While nonlinear averaging predicted higher or the same herbivore performance on a variable defense than on an invariable defense, we show that variability actually decreased herbivore performance and population growth rate. Defense variability reduces herbivore performance in a way that is more than the average of its parts. This is consistent with constraints in physiological matching of detoxification systems for herbivores experiencing variable toxin levels in their diet and represents a more generalizable way of understanding the impacts of variability on herbivory. Increasing defense variability in croplands at a scale encountered by individual herbivores can suppress herbivory, even if that is not anticipated by nonlinear averaging.

  12. Abscopal suppression of bone marrow erythropoiesis

    International Nuclear Information System (INIS)

    Werts, E.D.; Johnson, M.J.; DeGowin, R.L.

    1978-01-01

    Abscopal responses of hemopoietic tissue, which we noted in preliminary studies of mice receiving partial-body irradiation, led us to clarify these effects. In studies reported here, one hind leg of CF-1 female mice received 1000, 5000, or 10,000 rad of x radiation. We found a persistent shift from medullary to splenic erythropoiesis preventing anemia in mice receiving 5000 or 10,000 rad. Splenectomy prior to 5000-rad irradiation resulted in anemia, which was not ameliorated by exposure to intermittent hypoxia. Despite evidence for increased levels of erythropoietin in the animals, namely, a reticulocytosis and increased erythrocyte radioiron incorporation, both 59 Fe uptake and erythroblast counts in shielded marrow remained below normal. We found 50 to 90% suppression of the growth of marrow stromal colonies (MSC) from bone marrow aspirates of the shielded and irradiated femoral marrow at 1 month and at least 20% depression of MSC at 1 year, with each dose. We conclude that: (i) high doses of x radiation to one leg of mice caused prolonged suppression of medullary erythropoiesis with splenic compensation to prevent anemia; (ii) splenectomy, anemia, and hypoxia prevented the severe abscopal depression of medullary erythropoiesis; and (iii) suppressed medullary erythropoiesis with decreased growth of MSC suggested a change in the hemopoietic microenvironment of the bone marrow

  13. Adaptive Filtering for Aeroservoelastic Response Suppression, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — CSA Engineering proposes the design of an adaptive aeroelastic mode suppression for advanced fly-by-wire aircraft, which will partition the modal suppression...

  14. The Suppression of Internal Unrest in South West Africa (Namibia ...

    African Journals Online (AJOL)

    AM Fokkens

    suppression of the Bondelswarts and the actions against Chief Ipumbu. This article .... firepower was an appropriate response to suppress the uprising of local ..... Morris accompanied by Beukes and a commando of 50 men, moved east.

  15. Exploring Genetic Suppression Interactions on a Global Scale

    OpenAIRE

    van Leeuwen, Jolanda; Pons, Carles; Mellor, Joseph C.; Yamaguchi, Takafumi N.; Friesen, Helena; Koschwanez, John; Ušaj, Mojca Mattiazzi; Pechlaner, Maria; Takar, Mehmet; Ušaj, Matej; VanderSluis, Benjamin; Andrusiak, Kerry; Bansal, Pritpal; Baryshnikova, Anastasia; Boone, Claire

    2016-01-01

    Genetic suppression occurs when the phenotypic defects caused by a mutation in a particular gene are rescued by a mutation in a second gene. To explore the principles of genetic suppression, we examined both literature-curated and unbiased experimental data, involving systematic genetic mapping and whole-genome sequencing, to generate a large-scale suppression network among yeast genes. Most suppression pairs identified novel relationships among functionally related genes, providing new insig...

  16. Optogenetic and pharmacological suppression of spatial clusters of face neurons reveal their causal role in face gender discrimination.

    Science.gov (United States)

    Afraz, Arash; Boyden, Edward S; DiCarlo, James J

    2015-05-26

    Neurons that respond more to images of faces over nonface objects were identified in the inferior temporal (IT) cortex of primates three decades ago. Although it is hypothesized that perceptual discrimination between faces depends on the neural activity of IT subregions enriched with "face neurons," such a causal link has not been directly established. Here, using optogenetic and pharmacological methods, we reversibly suppressed the neural activity in small subregions of IT cortex of macaque monkeys performing a facial gender-discrimination task. Each type of intervention independently demonstrated that suppression of IT subregions enriched in face neurons induced a contralateral deficit in face gender-discrimination behavior. The same neural suppression of other IT subregions produced no detectable change in behavior. These results establish a causal link between the neural activity in IT face neuron subregions and face gender-discrimination behavior. Also, the demonstration that brief neural suppression of specific spatial subregions of IT induces behavioral effects opens the door for applying the technical advantages of optogenetics to a systematic attack on the causal relationship between IT cortex and high-level visual perception.

  17. Consensus and experience trump leadership, suppressing individual personality during social foraging.

    Science.gov (United States)

    McDonald, Nicholas D; Rands, Sean A; Hill, Francesca; Elder, Charlotte; Ioannou, Christos C

    2016-09-01

    Whether individual behavior in social settings correlates with behavior when individuals are alone is a fundamental question in collective behavior. However, evidence for whether behavior correlates across asocial and social settings is mixed, and no study has linked observed trends with underlying mechanisms. Consistent differences between individuals in boldness, which describes willingness to accept reward over risk, are likely to be under strong selection pressure. By testing three-spined sticklebacks (Gasterosteus aculeatus) in a risky foraging task alone and repeatedly in shoals, we demonstrate that the expression of boldness in groups is context-specific. Whereas personality is repeatable in a low-risk behavior (leaving a refuge), the collectively made consensus decision to then cross the arena outweighs leadership by bolder individuals, explaining the suppression of personality in this context. However, despite this social coordination, bolder individuals were still more likely to feed. Habituation and satiation over repeated trials degrade the effect of personality on leaving the refuge and also whether crossing the arena is a collective decision. The suppression of personality in groups suggests that individual risk-taking tendency may rarely represent actual risk in social settings, with implications for the evolution and ecology of personality variation.

  18. Consensus and experience trump leadership, suppressing individual personality during social foraging

    Science.gov (United States)

    McDonald, Nicholas D.; Rands, Sean A.; Hill, Francesca; Elder, Charlotte; Ioannou, Christos C.

    2016-01-01

    Whether individual behavior in social settings correlates with behavior when individuals are alone is a fundamental question in collective behavior. However, evidence for whether behavior correlates across asocial and social settings is mixed, and no study has linked observed trends with underlying mechanisms. Consistent differences between individuals in boldness, which describes willingness to accept reward over risk, are likely to be under strong selection pressure. By testing three-spined sticklebacks (Gasterosteus aculeatus) in a risky foraging task alone and repeatedly in shoals, we demonstrate that the expression of boldness in groups is context-specific. Whereas personality is repeatable in a low-risk behavior (leaving a refuge), the collectively made consensus decision to then cross the arena outweighs leadership by bolder individuals, explaining the suppression of personality in this context. However, despite this social coordination, bolder individuals were still more likely to feed. Habituation and satiation over repeated trials degrade the effect of personality on leaving the refuge and also whether crossing the arena is a collective decision. The suppression of personality in groups suggests that individual risk-taking tendency may rarely represent actual risk in social settings, with implications for the evolution and ecology of personality variation. PMID:27652342

  19. Compost made of organic wastes suppresses fusariosis

    Science.gov (United States)

    Kuryntseva, Polina; Galitskaya, Polina; Biktasheva, Liliya; Selivanovkaya, Svetlana

    2017-04-01

    Fungal plant diseases cause dramatic yield losses worldwide. Usually, pesticides are used for soil sanitation, and it results in practically pest-free soils, although pesticides cause a biological vacuum, which present many horticultural disadvantages. Suppressive composts, which possess both fertilizing properties for plants and inhibiting properties for plant pathogens, represent an effective and environmentally friendly alternative to conventional pesticides. In this study, composts obtained from agricultural organic wastes were applied to suppress Fusarium oxysporum of tomato plants in model experiments. Composts were made of mixtures of the widespread organic wastes sampled in Tatarstan (Russia): straw (SW), corn wastes (CW), chicken manure (ChM), cattle manure (CM) and swine manure (SM). 11 two- and three-component mixtures were prepared to obtain the optimal carbon-nitrogen, moisture and pH balances, and composted for 210 days. It was found that the thermophilic phase of composting in all the mixtures lasted from 2 to 35 days, and was characterized by significant fluctuations in temperature, i.e. from 27°C to 59°C. In the initial mixtures, the dissolved organic carbon (DOC) content was between 10 and 62 mg kg-1; it fell significantly on day 13, and then continuously decreased up to day 102, and subsequently remained low. For all the mixtures, maximal respiration activity was observed in the beginning of composting (231.9 mg CO2-C g-1 day-1). After 23 days, this parameter decreased significantly, and fluctuations subsided. The phytotoxicity of the initial compost mixtures varied from 18% (SW+SM) to 100% (CW+ChM+SM, CW+ChM); however, the trends in the dynamics were similar. After 120 days of composting, 5 of 11 samples were not phytotoxic. After 120 days of composting, each mixture was divided into two parts; one was inoculated with a biopreparation consisting of four microbial strains (Trichoderma asperellum, Pseudomonas putida, Pseudomonas fluorescens and

  20. One-tone suppression in the frog auditory nerve

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, J; Jørgensen, M B

    1996-01-01

    Sixty-seven fibers of a sample of 401 in the auditory nerve of grassfrogs (Rana temporaria) showed one-tone suppression, i.e., their spontaneous activity was suppressed by tones. All fibers were afferents from the amphibian papilla with best frequencies between 100 and 400 Hz. Best suppression...

  1. Venture capital: States suffer as suppression expenses climb

    Science.gov (United States)

    Krista Gebert

    2008-01-01

    The high cost of suppressing wildfires is taking a toll on federal and state agencies alike. Large wildland fires are complex, costly events influenced by a vast array of physical, climatic, and social factors. During five of the last eight years, the Forest Services' wildfire suppression expenditures have topped $1 billion, and total federal wildland suppression...

  2. Microbial enrichment to enhance the disease suppressive activity of compost

    NARCIS (Netherlands)

    Postma, J.; Montenari, M.; Boogert, van den P.H.J.F.

    2003-01-01

    Compost amended soil has been found to be suppressive against plant diseases in various cropping systems. The level and reproducibility of disease suppressive properties of compost might be increased by the addition of antagonists. In the present study, the establishment and suppressive activity of

  3. A paradoxical signal intensity increase in fatty livers using opposed-phase gradient echo imaging with fat-suppression pulses

    International Nuclear Information System (INIS)

    Mulkern, Robert V.; Voss, Stephan; Loeb Salsberg, Sandra; Krauel, Marta Ramon; Ludwig, David S.

    2008-01-01

    With the increase in obese and overweight children, nonalcoholic fatty liver disease has become more prevalent in the pediatric population. Appreciating subtleties of magnetic resonance (MR) signal intensity behavior from fatty livers under different imaging conditions thus becomes important to pediatric radiologists. We report an initially confusing signal behavior - increased signal from fatty livers when fat-suppression pulses are applied in an opposed-phase gradient echo imaging sequence - and seek to explain the physical mechanisms for this paradoxical signal intensity behavior. Abdominal MR imaging at 3 T with a 3-D volumetric interpolated breath-hold (VIBE) sequence in the opposed-phase condition (TR/TE 3.3/1.3 ms) was performed in five obese boys (14±2 years of age, body mass index >95th percentile for age and sex) with spectroscopically confirmed fatty livers. Two VIBE acquisitions were performed, one with and one without the use of chemical shift selective (CHESS) pulse fat suppression. The ratios of fat-suppressed over non-fat-suppressed signal intensities were assessed in regions-of-interest (ROIs) in five tissues: subcutaneous fat, liver, vertebral marrow, muscle and spleen. The boys had spectroscopically estimated hepatic fat levels between 17% and 48%. CHESS pulse fat suppression decreased subcutaneous fat signals dramatically, by more than 85% within regions of optimal fat suppression. Fatty liver signals, in contrast, were elevated by an average of 87% with CHESS pulse fat suppression. Vertebral marrow signal was also significantly elevated with CHESS pulse fat suppression, while spleen and muscle signals demonstrated only small signal increases on the order of 10%. We demonstrated that CHESS pulse fat suppression actually increases the signal intensity from fatty livers in opposed-phase gradient echo imaging conditions. The increase can be attributed to suppression of one partner of the opposed-phase pair that normally contributes to the

  4. A paradoxical signal intensity increase in fatty livers using opposed-phase gradient echo imaging with fat-suppression pulses

    Energy Technology Data Exchange (ETDEWEB)

    Mulkern, Robert V.; Voss, Stephan [Harvard Medical School, Department of Radiology, Children' s Hospital Boston, Boston, MA (United States); Loeb Salsberg, Sandra; Krauel, Marta Ramon; Ludwig, David S. [Harvard Medical School, Department of Medicine, Children' s Hospital Boston, Boston, MA (United States)

    2008-10-15

    With the increase in obese and overweight children, nonalcoholic fatty liver disease has become more prevalent in the pediatric population. Appreciating subtleties of magnetic resonance (MR) signal intensity behavior from fatty livers under different imaging conditions thus becomes important to pediatric radiologists. We report an initially confusing signal behavior - increased signal from fatty livers when fat-suppression pulses are applied in an opposed-phase gradient echo imaging sequence - and seek to explain the physical mechanisms for this paradoxical signal intensity behavior. Abdominal MR imaging at 3 T with a 3-D volumetric interpolated breath-hold (VIBE) sequence in the opposed-phase condition (TR/TE 3.3/1.3 ms) was performed in five obese boys (14{+-}2 years of age, body mass index >95th percentile for age and sex) with spectroscopically confirmed fatty livers. Two VIBE acquisitions were performed, one with and one without the use of chemical shift selective (CHESS) pulse fat suppression. The ratios of fat-suppressed over non-fat-suppressed signal intensities were assessed in regions-of-interest (ROIs) in five tissues: subcutaneous fat, liver, vertebral marrow, muscle and spleen. The boys had spectroscopically estimated hepatic fat levels between 17% and 48%. CHESS pulse fat suppression decreased subcutaneous fat signals dramatically, by more than 85% within regions of optimal fat suppression. Fatty liver signals, in contrast, were elevated by an average of 87% with CHESS pulse fat suppression. Vertebral marrow signal was also significantly elevated with CHESS pulse fat suppression, while spleen and muscle signals demonstrated only small signal increases on the order of 10%. We demonstrated that CHESS pulse fat suppression actually increases the signal intensity from fatty livers in opposed-phase gradient echo imaging conditions. The increase can be attributed to suppression of one partner of the opposed-phase pair that normally contributes to the

  5. Behavioral economics

    OpenAIRE

    Camerer, Colin F.

    2014-01-01

    Economics, like behavioral psychology, is a science of behavior, albeit highly organized human behavior. The value of economic concepts for behavioral psychology rests on (1) their empirical validity when tested in the laboratory with individual subjects and (2) their uniqueness when compared to established behavioral concepts. Several fundamental concepts are introduced and illustrated by reference to experimental data: open and closed economies, elastic and inelastic demand, and substitutio...

  6. Why expressive suppression does not pay? Cognitive costs of negative emotion suppression: The mediating role of subjective tense-arousal

    Directory of Open Access Journals (Sweden)

    Szczygieł Dorota

    2015-09-01

    Full Text Available The aim of this paper was to contribute to a broader understanding of the cognitive consequences of expressive suppression. Specifically, we examined whether the deteriorating effect of expressive suppression on cognitive functioning is caused by tense arousal enhanced by suppression. Two experiments were performed in order to test this prediction. In both studies we tested the effect of expressive suppression on working memory, as measured with a backwards digit-span task (Study 1, N = 43 and anagram problem-solving task (Study 2, N = 60. In addition, in Study 2 we tested whether expressive suppression degrades memory of the events that emerged during the period of expressive suppression. Both studies were conducted in a similar design: Participants watched a film clip which evoked negative emotions (i.e. disgust in Study 1 and a combination of sadness and anxiety in Study 2 under the instruction to suppress those negative emotions or (in the control condition to simply watch the film. The results of these experiments lead to three conclusions. First, the results reveal that expressive suppression degrades memory of the events that emerged during the period of expressive suppression and leads to poorer performance on working memory tasks, as measured with a backwards digit-span task and anagram problem-solving task. Second, the results indicate that expressive suppression leads to a significant increase in subjective tense arousal. Third, the results support our prediction that expressive suppression decreases cognitive performance through its effects on subjective tense arousal. The results of the Study 1 show that tense arousal activated during expressive suppression of disgust fully mediates the negative effect of suppression on working memory as measured with a backwards digit-span task. The results of Study 2 reveal that subjective tense arousal elicited while suppressing sadness and anxiety mediates both the effect of suppression on

  7. Interaction Effect of Social Isolation and High Dose Corticosteroid on Neurogenesis and Emotional Behavior

    OpenAIRE

    Chan, Jackie N.-M.; Lee, Jada C.-D.; Lee, Sylvia S. P.; Hui, Katy K. Y.; Chan, Alan H. L.; Fung, Timothy K.-H.; S?nchez-Vida?a, Dalinda I.; Lau, Benson W.-M.; Ngai, Shirley P.-C.

    2017-01-01

    Hypercortisolemia is one of the clinical features found in depressed patients. This clinical feature has been mimicked in animal studies via application of exogenous corticosterone (CORT). Previous studies suggested that CORT can induce behavioral disturbance in anxious-depressive like behavior, which is associated with suppressed neurogenesis. Hippocampal neurogenesis plays an important role in adult cognitive and behavioral regulation. Its suppression may thus lead to neuropsychiatric disor...

  8. Psychophysical research progress of interocular suppression in amblyopic visual system

    Directory of Open Access Journals (Sweden)

    Jing-Jing Li

    2016-03-01

    Full Text Available Some recent animal experiments and psychophysical studies indicate that patients with amblyopia have a structurally intact binocular visual system that is rendered functionally monocular due to suppression, and interocular suppression is a key mechanism in visual deficits experienced by patients with amblyopia. The aim of this review is to provide an overview of recent psychophysical findings that have investigated the important role of interocular suppression in amblyopia, the measurement and modulation of suppression, and new dichoptic treatment intervention that directly target suppression.

  9. Subjective duration distortions mirror neural repetition suppression.

    Directory of Open Access Journals (Sweden)

    Vani Pariyadath

    Full Text Available Subjective duration is strongly influenced by repetition and novelty, such that an oddball stimulus in a stream of repeated stimuli appears to last longer in duration in comparison. We hypothesize that this duration illusion, called the temporal oddball effect, is a result of the difference in expectation between the oddball and the repeated stimuli. Specifically, we conjecture that the repeated stimuli contract in duration as a result of increased predictability; these duration contractions, we suggest, result from decreased neural response amplitude with repetition, known as repetition suppression.Participants viewed trials consisting of lines presented at a particular orientation (standard stimuli followed by a line presented at a different orientation (oddball stimulus. We found that the size of the oddball effect correlates with the number of repetitions of the standard stimulus as well as the amount of deviance from the oddball stimulus; both of these results are consistent with a repetition suppression hypothesis. Further, we find that the temporal oddball effect is sensitive to experimental context--that is, the size of the oddball effect for a particular experimental trial is influenced by the range of duration distortions seen in preceding trials.Our data suggest that the repetition-related duration contractions causing the oddball effect are a result of neural repetition suppression. More generally, subjective duration may reflect the prediction error associated with a stimulus and, consequently, the efficiency of encoding that stimulus. Additionally, we emphasize that experimental context effects need to be taken into consideration when designing duration-related tasks.

  10. Bone-suppressed radiography using machine learning

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jun Beom; Kim, Dae Cheon; Kim, Ho Kyung [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The single-shot dual-energy imaging suffers from reduced contrast-to-noise ratio performance due to poor spectral separation. Tomosynthesis requires more complex motion equipment and may require higher patient dose. An alternative tissue-specific imaging technique was introduced. This alternative technique usually possesses a filter to generate bone-only images for given digital radiographs. Therefore, it provides soft-tissue-enhanced images from the subtraction of given radiographs and filtered bone-only images. Only bone-suppressed imaging capability is a limitation of the method. The filter can be obtained from a machine-learning algorithm, e.g. artificial neural network (ANN), with the dual-energy bone-only images (called 'teaching' images). We suspect the robustness of the filter may be dependent upon the number of teaching images and the number of patients from whose radiographs we obtain the teaching images. In this study, we design an ANN to obtain a bone-extracting filter from a radiograph, and investigate the filter properties with respect to various ANN parameters. Preliminary results are summarized in Fig. 3. We extracted 5,000 subregions in a 21x21 pixel format from the lung region in the bone-enhanced dual-energy image and we used them for teaching images during training the ANN. The resultant bone-enhanced image from the ANN nonlinear filter is shown in Fig. 3 (a). From the weighted logarithmic subtraction between Fig. 2 (a) and Fig. 3 (a), we could obtain the bone-suppressed image as shown in Fig. 3 (b). The quality of the bone-suppressed image is comparable to the ground truth Fig. 2 (c).

  11. Glechoma hederacea Suppresses RANKL-mediated Osteoclastogenesis.

    Science.gov (United States)

    Hwang, J K; Erkhembaatar, M; Gu, D R; Lee, S H; Lee, C H; Shin, D M; Lee, Y R; Kim, M S

    2014-07-01

    Glechoma hederacea (GH), commonly known as ground-ivy or gill-over-the-ground, has been extensively used in folk remedies for relieving symptoms of inflammatory disorders. However, the molecular mechanisms underlying the therapeutic action of GH are poorly understood. Here, we demonstrate that GH constituents inhibit osteoclastogenesis by abrogating receptor activator of nuclear κ-B ligand (RANKL)-induced free cytosolic Ca(2+) ([Ca(2+)]i) oscillations. To evaluate the effect of GH on osteoclastogenesis, we assessed the formation of multi-nucleated cells (MNCs), enzymatic activity of tartrate-resistant acidic phosphatase (TRAP), expression of nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), and [Ca(2+)]i alterations in response to treatment with GH ethanol extract (GHE) in primarily cultured bone marrow-derived macrophages (BMMs). Treatment of RANKL-stimulated or non-stimulated BMMs with GHE markedly suppressed MNC formation, TRAP activity, and NFATc1 expression in a dose-dependent manner. Additionally, GHE treatment induced a large transient elevation in [Ca(2+)]i while suppressing RANKL-induced [Ca(2+)]i oscillations, which are essential for NFATc1 activation. GHE-evoked increase in [Ca(2+)]i was dependent on extracellular Ca(2+) and was inhibited by 1,4-dihydropyridine (DHP), inhibitor of voltage-gated Ca(2+) channels (VGCCs), but was independent of store-operated Ca(2+) channels. Notably, after transient [Ca(2+)] elevation, treatment with GHE desensitized the VGCCs, resulting in an abrogation of RANKL-induced [Ca(2+)]i oscillations and MNC formation. These findings demonstrate that treatment of BMMs with GHE suppresses RANKL-mediated osteoclastogenesis by activating and then desensitizing DHP-sensitive VGCCs, suggesting potential applications of GH in the treatment of bone disorders, such as periodontitis, osteoporosis, and rheumatoid arthritis. © International & American Associations for Dental Research.

  12. Bone-suppressed radiography using machine learning

    International Nuclear Information System (INIS)

    Park, Jun Beom; Kim, Dae Cheon; Kim, Ho Kyung

    2016-01-01

    The single-shot dual-energy imaging suffers from reduced contrast-to-noise ratio performance due to poor spectral separation. Tomosynthesis requires more complex motion equipment and may require higher patient dose. An alternative tissue-specific imaging technique was introduced. This alternative technique usually possesses a filter to generate bone-only images for given digital radiographs. Therefore, it provides soft-tissue-enhanced images from the subtraction of given radiographs and filtered bone-only images. Only bone-suppressed imaging capability is a limitation of the method. The filter can be obtained from a machine-learning algorithm, e.g. artificial neural network (ANN), with the dual-energy bone-only images (called 'teaching' images). We suspect the robustness of the filter may be dependent upon the number of teaching images and the number of patients from whose radiographs we obtain the teaching images. In this study, we design an ANN to obtain a bone-extracting filter from a radiograph, and investigate the filter properties with respect to various ANN parameters. Preliminary results are summarized in Fig. 3. We extracted 5,000 subregions in a 21x21 pixel format from the lung region in the bone-enhanced dual-energy image and we used them for teaching images during training the ANN. The resultant bone-enhanced image from the ANN nonlinear filter is shown in Fig. 3 (a). From the weighted logarithmic subtraction between Fig. 2 (a) and Fig. 3 (a), we could obtain the bone-suppressed image as shown in Fig. 3 (b). The quality of the bone-suppressed image is comparable to the ground truth Fig. 2 (c).

  13. Fire suppression as a thermal implosion

    Science.gov (United States)

    Novozhilov, Vasily

    2017-01-01

    The present paper discusses the possibility of the thermal implosion scenario. This process would be a reverse of the well known thermal explosion (autoignition) phenomenon. The mechanism for thermal implosion scenario is proposed which involves quick suppression of the turbulent diffusion flame. Classical concept of the thermal explosion is discussed first. Then a possible scenario for the reverse process (thermal implosion) is discussed and illustrated by a relevant mathematical model. Based on the arguments presented in the paper, thermal implosion may be observed as an unstable equilibrium point on the generalized Semenov diagram for turbulent flame, however this hypothesis requires ultimate experimental confirmation.

  14. Applications of zero-suppressed decision diagrams

    CERN Document Server

    Sasao, Tsutomu

    2014-01-01

    A zero-suppressed decision diagram (ZDD) is a data structure to represent objects that typically contain many zeros. Applications include combinatorial problems, such as graphs, circuits, faults, and data mining. This book consists of four chapters on the applications of ZDDs. The first chapter by Alan Mishchenko introduces the ZDD. It compares ZDDs to BDDs, showing why a more compact representation is usually achieved in a ZDD. The focus is on sets of subsets and on sum-of-products (SOP) expressions. Methods to generate all the prime implicants (PIs), and to generate irredundant SOPs are show

  15. Experimental Status Of $J/\\psi$ Suppression

    CERN Document Server

    Kluberg, L; Alessandro, B; Alexa, C; Arnaldi, R; Astruc, J; Atayan, M; Baglin, C; Baldit, A; Bedjidian, M; Bellaiche, F; Beolè, S; Boldea, V; Bordalo, P; Bussière, A; Capelli,L; Capony, V; Casagrande, L; Castor, J; Chambon, T; Chaurand, B; Chevrot, I; Cheynis, B; Chiavassa, E; Cicalò, C; Comets, M P; Constans, N; Constantinescu, S; Cruz, J; De Falco, A; De Marco, N; Dellacasa, G; Devaux, A; Dita, S; Drapier, O; Ducroux, L; Espagnon, B; Fargeix, J; Filippov, S N; Fleuret, F; Force, P; Gallio, M; Gavrilov, Y K; Gerschel, C; Giubellino, P; Golubeva, M B; Gonin, M; Grigorian, A A; Grossiord, J Y; Guber, F F; Guichard, A; Gulkanyan, H; Hakobyan, R; Haroutunian, R; Idzik, M; Jouan, D; Karavitcheva, T L; Kurepin, A B; Le Bornec, Y; Lourenrço, C; Macciotta, P; Mac Cormick, M; Marzari- Chiesa, A; Masera, M; Masoni, A; Mehrabyan, S; Monteno, M; Mourgues, S; Musso, A; Ohlsson-Malek, F; Petiau, P; Piccotti, A; Pizzi, J R; Prado da Silva, W L; Puddu, G; Quintans, C; Racca, C; Ramello, L; Ramos, S; Rato-Mendes, P; Riccati, L; Romana, A; Ropotar, I; Saturnini, P; Scomparin, E; Serci, S; Shahoyan, R; Silva, S; Sitta, M; Soave, C; Sonderegger, P; Tarrago, X; Topilskaya, N S; Usai, G L; Vercellin, E; Villatte, L; Willis, N

    2001-01-01

    The most recent results obtained by experiment NA50 show that the $J /\\psi$ cross-section per nucleon-nucleon collision in semi-peripheral Pb-Pb reactions is "normally" suppressed in the sense that it follows the trend already observed from p-p and up to the most central S-U reactions. A clear change of behaviour is observed for more central Pb-Pb collisions which could be due to the transition of normal nuclear matter to its predicted Quark-Gluon Plasma state

  16. Improved attractants for enhancing tsetse fly suppression

    International Nuclear Information System (INIS)

    2003-09-01

    At the initiation of this co-ordinated research project (CRP), the available visually attractant devices and odours for entomological monitoring and for suppression of tsetse fly populations were not equally effective against all economically important tsetse fly species. For species like G. austeni, G. brevipalpis, G. swynnertoni and some species of the PALPALIS-group of tsetse flies no sufficiently effective combinations of visual or odour attractants were available for efficient suppression and standardized monitoring as part of an operational integrated intervention campaign against the tsetse and trypanosomosis (T and T) problem. The Co-ordinated Research Project on Improved Attractants for Enhancing the Efficiency of Tsetse Fly Suppression Operations and Barrier Systems used in Tsetse Control/Eradication Campaigns involved (a) the identification, synthesis and provision of candidate kairomones, their analogues and of dispensers; (b) laboratory screening of synthesised candidate kairomones through electrophysiological studies and wind tunnel experiments; (c) field tests of candidate kairomones alone or as part of odour blends, in combination with available and or new trap designs; and (d) analysis of hydrocarbons that influence tsetse sexual behaviour. The CRP accomplished several main objectives, namely: - The screening of new structurally related compounds, including specific stereoisomers, of known tsetse attractants resulted in the identification of several new candidate odour attractants with promising potential. - An efficient two-step synthetic method was developed for the pilot plant scale production of 3-n-propyphenol, synergistic tsetse kairomone component. - Electrophysiological experiments complemented with wind tunnel studies provided an efficient basis for the laboratory screening of candidate attractants prior to the initiation of laborious field tests. - New traps were identified and modifications of existing traps were tested for some species

  17. Pressure suppression system for a nuclear reactor

    International Nuclear Information System (INIS)

    Jost, N.

    1977-01-01

    The invention pertains to a pressure suppression system for PWR reactors where the parts enclosing the primary coolant are contained in two pressure-tight separate chambers. According to the invention, these chambers are partly filled with water and are connected with each other below the water surface. This way, gases cannot escape from the containment, not even if a valve and a line are damaged at the same time, as the vapours released condensate in the water of at least one of the other chambers. (HP) [de

  18. Fractional order absolute vibration suppression (AVS) controllers

    Science.gov (United States)

    Halevi, Yoram

    2017-04-01

    Absolute vibration suppression (AVS) is a control method for flexible structures. The first step is an accurate, infinite dimension, transfer function (TF), from actuation to measurement. This leads to the collocated, rate feedback AVS controller that in some cases completely eliminates the vibration. In case of the 1D wave equation, the TF consists of pure time delays and low order rational terms, and the AVS controller is rational. In all other cases, the TF and consequently the controller are fractional order in both the delays and the "rational parts". The paper considers stability, performance and actual implementation in such cases.

  19. The relation of weight suppression and BMI to bulimic symptoms.

    Science.gov (United States)

    Butryn, Meghan L; Juarascio, Adrienne; Lowe, Michael R

    2011-11-01

    High levels of weight suppression have been associated with greater binge eating and weight gain as well as poorer treatment outcome in bulimia nervosa. This study examined the relationship between weight suppression and bulimia nervosa symptoms and explored how weight suppression might interact with body mass index (BMI) in accounting for level of symptomatology at presentation for treatment. Participants were 64 women with threshold or sub-threshold bulimia nervosa. A clinical interview assessed binge eating and purging. Weight suppression and the interaction between BMI and weight suppression predicted frequency of binge eating such that participants with low BMI and high weight suppression engaged in the most binge eating. High levels of weight suppression also predicted more frequent purging. Additional research is warranted to examine mediators of these relationships. Copyright © 2010 Wiley Periodicals, Inc.

  20. Emotional Suppression as A Moderator of the Impact of Transgression on Consumers’ Satisfaction

    Directory of Open Access Journals (Sweden)

    Danielle Mantovani

    2013-12-01

    Full Text Available Despite the increasing amount of research about the effects of a seller’s transgression on consumers’ relationship quality evaluation, existing theory still demands more insight into consumer’s capacity to suppress the negative emotions that a transgression might generate. This research proposes that consumers’ are not always equally influenced by a transgression because some individuals demonstrate a higher capacity to suppress the negative emotions that arise from a seller’s transgression. An experimental study in a controlled virtual bookstore was developed, simulating a real website. Participants were randomly allocated into one of the two conditions: transgression vs. non-transgression scenario. We demonstrate that consumers who are better able to suppress the negative emotions experienced a lower decrease in their satisfaction evaluation of the relationship with the seller after a transgression than those who had a lower negative emotion suppression capacity following the behavior. These results shed light into the boundary conditions of the transgressions in the business to consumer marketing relationship. This research is therefore intended to make contributions to the literature of marketing relationship in a transgression context. 

  1. Targeting acceptance in the management of food craving: The mediating roles of eating styles and thought suppression.

    Science.gov (United States)

    Coffino, Jaime A; Heiss, Sydney; Hormes, Julia M

    2018-04-01

    Food craving is now widely considered to be a cognitively motivated state. Acceptance-based treatments are effective in reducing the adverse impact of food cravings on consumption, via a hypothesized decrease in experiential avoidance. The mechanisms that drive the success of acceptance-based management of craving remain to be empirically tested. This study examined the role of eating styles and thought suppression as mediators in the relationship between experiential avoidance and craving. Participants (n = 298, 51.5% female) completed the Food Craving Acceptance and Awareness Questionnaire (FAAQ), the Dutch Eating Behavior Questionnaire (DEBQ), the White Bear Suppression Inventory (WBSI; a measure of thought suppression), and the reduced version of the Food Craving Questionnaire- Trait (FCQ-T-r). Scores on the FAAQ were inversely associated with scores on the FCQ-T-r, DEBQ, and WBSI; FCQ-T-r scores were positively correlated with scores on the DEBQ and WBSI (all p styles and thought suppression, acceptance remained a significant predictor of craving. Results thus provide initial evidence that eating styles and thought suppression mediate the relationship between food-specific experiential avoidance and food craving. Findings lay the foundation for future study of the proximal antecedents of food cravings and lend preliminary support for targeting thought suppression and eating styles in acceptance-based approaches to the management of craving. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Aggressive Behavior

    Science.gov (United States)

    ... It is always more effective to positively reinforce desired behaviors and to teach children alternative behaviors rather ... he is angry, but instead to express his feelings through words. It’s important for him to learn ...

  3. Behaviorally inadequate

    DEFF Research Database (Denmark)

    Kasperbauer, Tyler Joshua

    2014-01-01

    According to situationism in psychology, behavior is primarily influenced by external situational factors rather than internal traits or motivations such as virtues. Environmental ethicists wish to promote pro-environmental behaviors capable of providing adequate protection for the environment...

  4. Reinstatement of Conditioned Suppression in Mice

    Directory of Open Access Journals (Sweden)

    Trinette Dirikx

    2006-03-01

    Full Text Available Return of fear after successful exposure therapy calls for a better understanding of the mechanisms of relapse. Classical conditioning research provides a useful framework for conceptualising the acquisition, extinction and reappearance of fear. The present paper focuses on reinstatement, the return of extinguished conditioned responses due to the experience of one or more unconditioned stimuli (USs after extinction. This phenomenon illustrates that unpredictable USs can lead to a return of fear after successful exposure. The data we present is one of the first demonstrations that conditioned suppression of instrumental behaviour can be used as an index of classical conditioning in laboratory mice. The procedure proves to be a promising instrument for assessing fear in mice, both in the context of research aimed at unravelling the functional characteristics of learning and memory in healthy mice and in the context of research aimed at unravelling the neurobiological substrate of psychiatric disorders, e.g., in studies with transgenic and knockout mice. Using this procedure, we report the first observation of reinstatement of conditioned suppression in this species.

  5. Suppression of Coronavirus Replication by Cyclophilin Inhibitors

    Directory of Open Access Journals (Sweden)

    Takashi Sasaki

    2013-05-01

    Full Text Available Coronaviruses infect a variety of mammalian and avian species and cause serious diseases in humans, cats, mice, and birds in the form of severe acute respiratory syndrome (SARS, feline infectious peritonitis (FIP, mouse hepatitis, and avian infectious bronchitis, respectively. No effective vaccine or treatment has been developed for SARS-coronavirus or FIP virus, both of which cause lethal diseases. It has been reported that a cyclophilin inhibitor, cyclosporin A (CsA, could inhibit the replication of coronaviruses. CsA is a well-known immunosuppressive drug that binds to cellular cyclophilins to inhibit calcineurin, a calcium-calmodulin-activated serine/threonine-specific phosphatase. The inhibition of calcineurin blocks the translocation of nuclear factor of activated T cells from the cytosol into the nucleus, thus preventing the transcription of genes encoding cytokines such as interleukin-2. Cyclophilins are peptidyl-prolyl isomerases with physiological functions that have been described for many years to include chaperone and foldase activities. Also, many viruses require cyclophilins for replication; these include human immunodeficiency virus, vesicular stomatitis virus, and hepatitis C virus. However, the molecular mechanisms leading to the suppression of viral replication differ for different viruses. This review describes the suppressive effects of CsA on coronavirus replication.

  6. Optimal digital filtering for tremor suppression.

    Science.gov (United States)

    Gonzalez, J G; Heredia, E A; Rahman, T; Barner, K E; Arce, G R

    2000-05-01

    Remote manually operated tasks such as those found in teleoperation, virtual reality, or joystick-based computer access, require the generation of an intermediate electrical signal which is transmitted to the controlled subsystem (robot arm, virtual environment, or a cursor in a computer screen). When human movements are distorted, for instance, by tremor, performance can be improved by digitally filtering the intermediate signal before it reaches the controlled device. This paper introduces a novel tremor filtering framework in which digital equalizers are optimally designed through pursuit tracking task experiments. Due to inherent properties of the man-machine system, the design of tremor suppression equalizers presents two serious problems: 1) performance criteria leading to optimizations that minimize mean-squared error are not efficient for tremor elimination and 2) movement signals show ill-conditioned autocorrelation matrices, which often result in useless or unstable solutions. To address these problems, a new performance indicator in the context of tremor is introduced, and the optimal equalizer according to this new criterion is developed. Ill-conditioning of the autocorrelation matrix is overcome using a novel method which we call pulled-optimization. Experiments performed with artificially induced vibrations and a subject with Parkinson's disease show significant improvement in performance. Additional results, along with MATLAB source code of the algorithms, and a customizable demo for PC joysticks, are available on the Internet at http:¿tremor-suppression.com.

  7. Tagging and suppression of pileup jets

    CERN Document Server

    The ATLAS collaboration

    2014-01-01

    The suppression of pileup jets has been a crucial component of many physics analyses using 2012 LHC proton-proton collisions. In ATLAS, tracking information has been used to calculate a variable called the jet-vertex-fraction, which is the fraction of the total mo- mentum of tracks in the jet which is associated to the primary vertex. Imposing a minimum on this variable rejects the majority of pileup jets, but leads to hard-scatter jet efficiencies that depend on the number of reconstructed primary vertices in the event ($N_{Vtx}$). In this note, new track-based variables to suppress pileup jets are developed in such a way that the resulting hard-scatter jet efficiency is stable as a function of $N_{Vtx}$. A multivariate combina- tion of two such variables called the jet-vertex-tagger is constructed. In addition, it is shown that jet-vertex association can be applied to large-R jets, providing a track-based grooming technique that is as powerful as calorimeter-based trimming but based on complementary trackin...

  8. Wireless Inductive Power Device Suppresses Blade Vibrations

    Science.gov (United States)

    Morrison, Carlos R.; Provenza, Andrew J.; Choi, Benjamin B.; Bakhle, Milind A.; Min, James B.; Stefko, George L.; Duffy, Kirsten P.; Fougers, Alan J.

    2011-01-01

    Vibration in turbomachinery can cause blade failures and leads to the use of heavier, thicker blades that result in lower aerodynamic efficiency and increased noise. Metal and/or composite fatigue in the blades of jet engines has resulted in blade destruction and loss of lives. Techniques for suppressing low-frequency blade vibration, such as gtuned circuit resistive dissipation of vibratory energy, h or simply "passive damping," can require electronics incorporating coils of unwieldy dimensions and adding unwanted weight to the rotor. Other approaches, using vibration-dampening devices or damping material, could add undesirable weight to the blades or hub, making them less efficient. A wireless inductive power device (WIPD) was designed, fabricated, and developed for use in the NASA Glenn's "Dynamic Spin Rig" (DSR) facility. The DSR is used to simulate the functionality of turbomachinery. The relatively small and lightweight device [10 lb (approx.=4.5 kg)] replaces the existing venerable and bulky slip-ring. The goal is the eventual integration of this technology into actual turbomachinery such as jet engines or electric power generators, wherein the device will facilitate the suppression of potentially destructive vibrations in fan blades. This technology obviates slip rings, which require cooling and can prove unreliable or be problematic over time. The WIPD consists of two parts: a remote element, which is positioned on the rotor and provides up to 100 W of electrical power to thin, lightweight piezoelectric patches strategically placed on/in fan blades; and a stationary base unit that wirelessly communicates with the remote unit. The base unit supplies inductive power, and also acts as an input and output corridor for wireless measurement, and active control command to the remote unit. Efficient engine operation necessitates minimal disturbance to the gas flow across the turbine blades in any effort to moderate blade vibration. This innovation makes it

  9. Verbal behavior

    OpenAIRE

    Michael, Jack

    1984-01-01

    The recent history and current status of the area of verbal behavior are considered in terms of three major thematic lines: the operant conditioning of adult verbal behavior, learning to be an effective speaker and listener, and developments directly related to Skinner's Verbal Behavior. Other topics not directly related to the main themes are also considered: the work of Kurt Salzinger, ape-language research, and human operant research related to rule-governed behavior.

  10. Suppression of grasshopper sound production by nitric oxide-releasing neurons of the central complex

    Science.gov (United States)

    Weinrich, Anja; Kunst, Michael; Wirmer, Andrea; Holstein, Gay R.

    2008-01-01

    The central complex of acridid grasshoppers integrates sensory information pertinent to reproduction-related acoustic communication. Activation of nitric oxide (NO)/cyclic GMP-signaling by injection of NO donors into the central complex of restrained Chorthippus biguttulus females suppresses muscarine-stimulated sound production. In contrast, sound production is released by aminoguanidine (AG)-mediated inhibition of nitric oxide synthase (NOS) in the central body, suggesting a basal release of NO that suppresses singing in this situation. Using anti-citrulline immunocytochemistry to detect recent NO production, subtypes of columnar neurons with somata located in the pars intercerebralis and tangential neurons with somata in the ventro-median protocerebrum were distinctly labeled. Their arborizations in the central body upper division overlap with expression patterns for NOS and with the site of injection where NO donors suppress sound production. Systemic application of AG increases the responsiveness of unrestrained females to male calling songs. Identical treatment with the NOS inhibitor that increased male song-stimulated sound production in females induced a marked reduction of citrulline accumulation in central complex columnar and tangential neurons. We conclude that behavioral situations that are unfavorable for sound production (like being restrained) activate NOS-expressing central body neurons to release NO and elevate the behavioral threshold for sound production in female grasshoppers. PMID:18574586

  11. Contribution of suppression difficulty and lessons learned in forecasting fire suppression operations productivity: A methodological approach

    Science.gov (United States)

    Francisco Rodríguez y Silva; Armando González-Cabán

    2016-01-01

    We propose an economic analysis using utility and productivity, and efficiency theories to provide fire managers a decision support tool to determine the most efficient fire management programs levels. By incorporating managers’ accumulated fire suppression experiences (capitalized experience) in the analysis we help fire managers...

  12. Behaviorally Speaking.

    Science.gov (United States)

    Porter, Elias H.; Dutton, Darell W. J.

    1987-01-01

    Consists of two articles focusing on (1) a modern behavioral model that takes cues from Hippocrates' Four Temperaments and (2) use of a behavioral approach to improve the effectiveness of meetings. Lists positive and negative behaviors within the meeting context. (CH)

  13. Bringing social identity to work: the influence of manifestation and suppression on perceived discrimination, job satisfaction, and turnover intentions.

    Science.gov (United States)

    Madera, Juan M; King, Eden B; Hebl, Michelle R

    2012-04-01

    In the current article, we explored whether manifesting or suppressing an identity (race/ethnicity, gender, age, religion, sexual orientation, or disability) at work is related to perceived discrimination, job satisfaction, and turnover intentions. Participants included 211 working adults who completed an online survey. The results showed that efforts to suppress a group identity were positively (and behavioral manifestations of group identity negatively) related to perceived discrimination, which predicted job satisfaction and turnover intentions. These results suggest that diverse employees actively manage their nonwork identities while at work and that these identity management strategies have important consequences. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  14. Acupuncture suppresses intravenous methamphetamine self-administration through GABA receptor's mediation.

    Science.gov (United States)

    Choi, Yi Jeong; Kim, Nam Jun; Zhao, Rong Jie; Kim, Da Hye; Yang, Chae Ha; Kim, Hee Young; Gwak, Young S; Jang, Eun Young; Kim, Jae Su; Lee, Yun Kyu; Lee, Hyun Jong; Lee, Sang Nam; Lim, Sung Chul; Lee, Bong Hyo

    2018-01-01

    Methamphetamine is one of the widely abused drugs. In spite of a number of studies, there is still little successful therapy to suppress the methamphetamine abuse. Acupuncture has shown to attenuate the reinforcing effects of psychostimulant. Based on, the present study investigated if acupuncture could suppress intravenous methamphetamine self-administration behavior. In addition, a possible neuronal mechanism was investigated. Male Sprague-Dawley rats weighing 270-300g were trained to intake food pellet. After catheter implantation, animal was trained to self-administer methamphetamine (0.05mg/kg) intravenously using fixed ratio 1 schedule in daily 2h session during 3 weeks. After training, rats who established baseline (infusion variation less than 20% of the mean for 3 consecutive days) received acupuncture treatment on the next day. Acupuncture was performed at each acupoint manually. In the second experiment, the selective antagonists of GABA A or GABA B receptor were given before acupuncture to investigate the possible neuronal involvement of GABA receptor pathway in the acupuncture effects. C-Fos expression was examined in the nucleus accumbens to support behavioral data. Acupuncture at HT7, but not at control acupoint LI5, reduced the self-administration behavior significantly. Also, the effects of acupuncture were blocked by the GABA receptor antagonists. C-Fos expression was shown to be parallel with the behavioral data. Results of this study have shown that acupuncture at HT7 suppressed methamphetamine self-administration through GABA receptor system, suggesting that acupuncture at HT7 can be a useful therapy for the treatment of methamphetamine abuse. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. A model for the calculation of vent clearing transients in pressure suppression systems

    International Nuclear Information System (INIS)

    Brosche, D.

    1975-01-01

    For the layout of a pressure suppression system of a light water cooled reactor (boiling water reactor) it is important to know the time dependent behavior of the vent clearing transient after a loss-of-coolant accident for two main reasons: time of the end of the vent clearing transient influences strongly the pressure and temperature maxima in the drywell and wetwell. Time-dependent behavior of the vent clearing transient influences pressure loads in the condensation pool of the wetwell and therefore pressure induced stresses to the structure. The time-dependent behavior of the water masses in the vent pipes and wetwell are described by the basic equations for a nonstationary incompressible friction flow: momentum equation, continuity equation and a correlation for the variation of the state of the gas volume in the wetwell above the water level. After many algebraic operations and integrations along the flow path, a single ordinary nonlinear differential equation for the variations of the water levels in the vent pipes and wetwell is obtained. Therefore the time-dependent velocities and accelerations of the water levels and the moment of the end clearing transient are known. The time-dependent pressure behavior in the drywell, geometrical conditions, initial submergence depth of the vent pipes and different friction and pressure loss factors are presented. The theoretical model has been tested at corresponding experiments performed at a full scale 1/48 segment of the Humboldt Bay pressure suppression containment in the USA and at the pressure suppression containment at the Marviken nuclear power station in Sweden. All these comparisons have shown good agreement between theory and experiment

  16. Rapamycin suppresses brain aging in senescence-accelerated OXYS rats.

    Science.gov (United States)

    Kolosova, Nataliya G; Vitovtov, Anton O; Muraleva, Natalia A; Akulov, Andrey E; Stefanova, Natalia A; Blagosklonny, Mikhail V

    2013-06-01

    Cellular and organismal aging are driven in part by the MTOR (mechanistic target of rapamycin) pathway and rapamycin extends life span inC elegans, Drosophila and mice. Herein, we investigated effects of rapamycin on brain aging in OXYS rats. Previously we found, in OXYS rats, an early development of age-associated pathological phenotypes similar to several geriatric disorders in humans, including cerebral dysfunctions. Behavioral alterations as well as learning and memory deficits develop by 3 months. Here we show that rapamycin treatment (0.1 or 0.5 mg/kg as a food mixture daily from the age of 1.5 to 3.5 months) decreased anxiety and improved locomotor and exploratory behavior in OXYS rats. In untreated OXYS rats, MRI revealed an increase of the area of hippocampus, substantial hydrocephalus and 2-fold increased area of the lateral ventricles. Rapamycin treatment prevented these abnormalities, erasing the difference between OXYS and Wister rats (used as control). All untreated OXYS rats showed signs of neurodegeneration, manifested by loci of demyelination. Rapamycin decreased the percentage of animals with demyelination and the number of loci. Levels of Tau and phospho-Tau (T181) were increased in OXYS rats (compared with Wistar). Rapamycin significantly decreased Tau and inhibited its phosphorylation in the hippocampus of OXYS and Wistar rats. Importantly, rapamycin treatment caused a compensatory increase in levels of S6 and correspondingly levels of phospo-S6 in the frontal cortex, indicating that some downstream events were compensatory preserved, explaining the lack of toxicity. We conclude that rapamycin in low chronic doses can suppress brain aging.

  17. Adaptive single-antenna transmit selection with interference suppression

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2011-10-01

    This paper studies the performance of adaptive transmit selection with co-channel interference suppression in multipath fading channels. The adaptive selection algorithms are configured for single-antenna bandwidth-efficient or power-efficient transmission with as low transmit channel estimations as possible. Due to the fact that the number of active co-channel interfering signals and their corresponding powers experience random behavior, the adaptation to channels conditions, assuming uniform buffer and traffic loading, is proposed to be jointly based on the transmit channels instantaneous signal-to-noise ratios (SNRs) and signal-to-interference-plus-noise ratios (SINRs). Two interference cancelation algorithms are considered. The first algorithm assumes that the receiver eliminates the impact of the strongest subset of interferers, whereas the second algorithm suggests random cancelation of interferers to further reduce processing complexity. The impact of outdated ordering of interferers powers on the efficiency of interference cancelation, and the effect of imperfect prediction of transmit channels for desired user adaptation are investigated. Analytical formulations for various performance measures and comparisons between the performance and processing complexity of different adaptation schemes are presented. © 2011 IEEE.

  18. Evidence of ghost suppression in gluon mass scale dynamics

    Science.gov (United States)

    Aguilar, A. C.; Binosi, D.; Figueiredo, C. T.; Papavassiliou, J.

    2018-03-01

    In this work we study the impact that the ghost sector of pure Yang-Mills theories may have on the generation of a dynamical gauge boson mass scale, which hinges on the appearance of massless poles in the fundamental vertices of the theory, and the subsequent realization of the well-known Schwinger mechanism. The process responsible for the formation of such structures is itself dynamical in nature, and is governed by a set of Bethe-Salpeter type of integral equations. While in previous studies the presence of massless poles was assumed to be exclusively associated with the background-gauge three-gluon vertex, in the present analysis we allow them to appear also in the corresponding ghost-gluon vertex. The full analysis of the resulting Bethe-Salpeter system reveals that the contribution of the poles associated with the ghost-gluon vertex are particularly suppressed, their sole discernible effect being a slight modification in the running of the gluon mass scale, for momenta larger than a few GeV. In addition, we examine the behavior of the (background-gauge) ghost-gluon vertex in the limit of vanishing ghost momentum, and derive the corresponding version of Taylor's theorem. These considerations, together with a suitable Ansatz, permit us the full reconstruction of the pole sector of the two vertices involved.

  19. Carnivore fecal chemicals suppress feeding by Alpine goats (Capra hircus).

    Science.gov (United States)

    Weldon, P J; Graham, D P; Mears, L P

    1993-12-01

    The efficacy of carnivore and ungulate fecal chemicals in suppressing the feeding behavior of Alpine goats (Capra hircus) was examined. In the first four experiments, goats were offered food covered with paper strips treated with fecal extracts of the Bengal tiger, Siberian tiger, African lion, and brown bear, respectively; food covered with solvent-treated and untreated (plain) papers served as controls in each experiment. Goats made fewer head entries into, and ate less food from, buckets containing fecal extracts. In the fifth experiment, goats were offered food covered with paper strips treated with fecal extracts of the puma, Dorcas gazelle, white-bearded gnu, and conspecifics; food covered with solvent-treated and plain papers again served as controls. The amounts of food consumed from buckets containing puma, gazelle, gnu, and solvent treatments were statistically indistinguishable, but less food was consumed from them than from buckets containing the goat-scented or plain papers. No significant differences among treatments were detected with respect to head entries. Field experiments are needed on the use of predator-derived chemicals to reduce damage by goats to vegetation.

  20. Incremental learning of perceptual and conceptual representations and the puzzle of neural repetition suppression.

    Science.gov (United States)

    Gotts, Stephen J

    2016-08-01

    Incremental learning models of long-term perceptual and conceptual knowledge hold that neural representations are gradually acquired over many individual experiences via Hebbian-like activity-dependent synaptic plasticity across cortical connections of the brain. In such models, variation in task relevance of information, anatomic constraints, and the statistics of sensory inputs and motor outputs lead to qualitative alterations in the nature of representations that are acquired. Here, the proposal that behavioral repetition priming and neural repetition suppression effects are empirical markers of incremental learning in the cortex is discussed, and research results that both support and challenge this position are reviewed. Discussion is focused on a recent fMRI-adaptation study from our laboratory that shows decoupling of experience-dependent changes in neural tuning, priming, and repetition suppression, with representational changes that appear to work counter to the explicit task demands. Finally, critical experiments that may help to clarify and resolve current challenges are outlined.

  1. Lens oscillations in the human eye. Implications for post-saccadic suppression of vision.

    Directory of Open Access Journals (Sweden)

    Juan Tabernero

    Full Text Available The eye changes gaze continuously from one visual stimulus to another. Using a high speed camera to record eye and lens movements we demonstrate how the crystalline lens sustains an inertial oscillatory decay movement immediately after every change of gaze. This behavior fit precisely with the movement of a classical damped harmonic oscillator. The time course of the oscillations range from 50 to 60 msec with an oscillation frequency of around 20 Hz. That has dramatic implications on the image quality at the retina on the very short times (∼50 msec that follow the movement. However, it is well known that our vision is nearly suppressed on those periods (post-saccadic suppression. Both phenomenon follow similar time courses and therefore might be synchronized to avoid the visual impairment.

  2. The generation and suppression of synchrotron sidebands

    International Nuclear Information System (INIS)

    Warren, R.W.; Goldstein, J.C.

    1987-01-01

    Computer simulations of FEL lasing differ in the degree to which they approximate real experiments. One of the FEL codes used extensively at Los Alamos takes account of the features of each electron micropulse and follows the growth and saturation of the optical micropulse. With no additional adjustments, this code displays the development of sidebands and demonstrates their control when optical filters of various kinds are used. Other codes that do not include a description of the micropulse do not automatically display sidebands but need to have artificial noise of some kind added. This is not unexpected because sidebands are generated by an FEL instability; instabilities, in general, need some kind of initiating disturbance. In this paper we: identify the disturbance that triggers the instability in the pulse code; discuss a practical way to suppress the instability without using filters; compare these results with experiments; and discuss these findings. 22 refs., 9 figs

  3. Probe suppression in conformal phased array

    CERN Document Server

    Singh, Hema; Neethu, P S

    2017-01-01

    This book considers a cylindrical phased array with microstrip patch antenna elements and half-wavelength dipole antenna elements. The effect of platform and mutual coupling effect is included in the analysis. The non-planar geometry is tackled by using Euler's transformation towards the calculation of array manifold. Results are presented for both conducting and dielectric cylinder. The optimal weights obtained are used to generate adapted pattern according to a given signal scenario. It is shown that array along with adaptive algorithm is able to cater to an arbitrary signal environment even when the platform effect and mutual coupling is taken into account. This book provides a step-by-step approach for analyzing the probe suppression in non-planar geometry. Its detailed illustrations and analysis will be a useful text for graduate and research students, scientists and engineers working in the area of phased arrays, low-observables and stealth technology.

  4. Obtuse triangle suppression in anisotropic meshes

    KAUST Repository

    Sun, Feng; Choi, Yi King; Wang, Wen Ping; Yan, Dongming; Liu, Yang; Lé vy, Bruno L.

    2011-01-01

    Anisotropic triangle meshes are used for efficient approximation of surfaces and flow data in finite element analysis, and in these applications it is desirable to have as few obtuse triangles as possible to reduce the discretization error. We present a variational approach to suppressing obtuse triangles in anisotropic meshes. Specifically, we introduce a hexagonal Minkowski metric, which is sensitive to triangle orientation, to give a new formulation of the centroidal Voronoi tessellation (CVT) method. Furthermore, we prove several relevant properties of the CVT method with the newly introduced metric. Experiments show that our algorithm produces anisotropic meshes with much fewer obtuse triangles than using existing methods while maintaining mesh anisotropy. © 2011 Elsevier B.V. All rights reserved.

  5. Void growth suppression by dislocation impurity atmospheres

    International Nuclear Information System (INIS)

    Weertman, J.; Green, W.V.

    1976-01-01

    A detailed calculation is given of the effect of an impurity atmosphere on void growth under irradiation damage conditions. Norris has proposed that such an atmosphere can suppress void growth. The hydrostatic stress field of a dislocation that is surrounded by an impurity atmosphere was found and used to calculate the change in the effective radius of a dislocation line as a sink for interstitials and vacancies. The calculation of the impurity concentration in a Cottrell cloud takes into account the change in hydrostatic pressure produced by the presence of the cloud itself. It is found that void growth is eliminated whenever dislocations are surrounded by a condensed atmosphere of either oversized substitutional impurity atoms or interstitial impurity atoms. A condensed atmosphere will form whenever the average impurity concentration is larger than a critical concentration

  6. In-beam background suppression shield

    DEFF Research Database (Denmark)

    Santoro, V.; Cai, Xiao Xiao; DiJulio, D. D.

    2015-01-01

    The long (3 ms) proton pulse of the European Spallation Source (ESS) gives rise to unique and potentially high backgrounds for the instrument suite. In such a source an instrument's capabilities will be limited by its Signal to Noise (S/N) ratio. The instruments with a direct view of the moderator......, which do not use a bender to help mitigate the fast neutron background, are the most challenging. For these beam lines we propose the innovative shielding of placing blocks of material directly into the guide system, which allow a minimum attenuation of the cold and thermal fluxes relative...... to the background suppression. This shielding configuration has been worked into a beam line model using Geant4. We study particularly the advantages of single crystal sapphire and silicon blocks....

  7. Suppression of fertility in adult cats

    DEFF Research Database (Denmark)

    Goericke-Pesch, Sandra Kathrin; Wehrend, A.; Georgiev, P.

    2014-01-01

    /needed? (iii) sex of the animal? New effective and available methods for hormonal contraception include melatonin implants for short-term post ponement of oestrus in adult queens and slow-release GnRH-agonist implants containing deslorelin (Suprelorin®) for short- and long-term contraception in male and female......Contents: Cats are animals with highly efficient reproduction, clearly pointing to a need for suppression of fertility. Although surgical contraception is highly effective, it is not always the method of choice. This is predominantly because it is cost-intensive, time-consuming and irreversible......, with the latter being of major importance for cat breeders. This article reviews the use of progestins, scleroting agents, immunocontraception, melatonin, GnRH antagonists and finally, GnRH agonists, in adult male and female cats in detail, according to the present state of the art. By now, various scientific...

  8. Suppression of coffee ring: (Particle) size matters

    Science.gov (United States)

    Bansal, Lalit; Seth, Pranjal; Murugappan, Bhubesh; Basu, Saptarshi

    2018-05-01

    Coffee ring patterns in drying sessile droplets are undesirable in various practical applications. Here, we experimentally demonstrate that on hydrophobic substrates, the coffee ring can be suppressed just by increasing the particle diameter. Particles with larger size flocculate within the evaporation timescale, leading to a significant gravimetric settling (for Pe > 1) triggering a uniform deposit. Interestingly, the transition to a uniform deposit is found to be independent of the internal flow field and substrate properties. Flocculation of particles also alters the particle packing at the nanoscale resulting in order to disorder transitions. In this letter, we exhibit a physical exposition on how particle size affects morphodynamics of the droplet drying at macro-nano length scales.

  9. Obtuse triangle suppression in anisotropic meshes

    KAUST Repository

    Sun, Feng

    2011-12-01

    Anisotropic triangle meshes are used for efficient approximation of surfaces and flow data in finite element analysis, and in these applications it is desirable to have as few obtuse triangles as possible to reduce the discretization error. We present a variational approach to suppressing obtuse triangles in anisotropic meshes. Specifically, we introduce a hexagonal Minkowski metric, which is sensitive to triangle orientation, to give a new formulation of the centroidal Voronoi tessellation (CVT) method. Furthermore, we prove several relevant properties of the CVT method with the newly introduced metric. Experiments show that our algorithm produces anisotropic meshes with much fewer obtuse triangles than using existing methods while maintaining mesh anisotropy. © 2011 Elsevier B.V. All rights reserved.

  10. Are Patents used to Suppress Useful Technology?

    DEFF Research Database (Denmark)

    Howells, John

    2006-01-01

    of innovation, other than in the trivial sense of excluding third parties from the right to develop the technology covered by the patent? There are many references to this possibility in the management, economic and legal literatures, but two highly-cited papers stand out for grounding their claims of corporate......This article examines the evidence behind claims that innovation is hindered or blocked (termed technology suppression) by corporations' use of patents. In other words, are there ways in which the exploitation of the exclusive development right of the patent can be shown to retard the process...... and the difference between economic monopoly and an exclusive right. It is argued here that what is at issue in this work is the proper function of the patent institution. It is shown early in this paper that the understanding of the patent institution as a system of development prospects makes better sense...

  11. Active vibration suppression of helicopter horizontal stabilizers

    Science.gov (United States)

    Cinquemani, Simone; Cazzulani, Gabriele; Resta, Ferruccio

    2017-04-01

    Helicopters are among the most complex machines ever made. While ensuring high performance from the aeronautical point of view, they are not very comfortable due to vibration mainly created by the main rotor and by the interaction with the surrounding air. One of the most solicited structural elements of the vehicle are the horizontal stabilizers. These elements are particularly stressed because of their composite structure which, while guaranteeing lightness and strength, is characterized by a low damping. This work makes a preliminary analysis on the dynamics of the structure and proposes different solutions to actively suppress vibrations. Among them, the best in terms of the relationship between performance and weight / complexity of the system is that based on inertial actuators mounted on the inside of the horizontal stabilizers. The work addresses the issue of the design of the device and its use in the stabilizer from both the numerical and the experimental points of view.

  12. Ion suppression from blood collection devices

    DEFF Research Database (Denmark)

    Hasselstrøm, Jørgen Bo; Sejr Gothelf, Aase

    The aim of the study was to examine the variation in ion suppression in ultra high pressure liquid chromatography tandem mass spectrometry (UHPLC-MS-MS) methods when using different blood collection devices. Three different methods measuring 18 antidepressants and antipsychotics in total were...... Terumo, S-monovette from Sarstedt, Vacuette from Greiner Bio-One and three BD Vacutainer serum tubes from BD. These seven different blood collection devices were used to withdraw blood from five healthy drug free donors (n=35) in random order. The samples were centrifuged and serum from each sample...... by UHPLC-MS-MS using three different gradients (Group I, II and III). The analytes in group I was measured on an Agilent 6460 mass spectrometer and group II and III were measured on an Agilent 6410 mass spectrometer both utilizing positive electrospray ionization. The experiments demonstrated significant...

  13. Neutrino wave function and oscillation suppression

    International Nuclear Information System (INIS)

    Dolgov, A.D.; Lychkovskiy, O.V.; Mamonov, A.A.; Okun, L.B.; Schepkin, M.G.

    2005-01-01

    We consider a thought experiment, in which a neutrino is produced by an electron on a nucleus in a crystal. The wave function of the oscillating neutrino is calculated assuming that the electron is described by a wave packet. If the electron is relativistic and the spatial size of its wave packet is much larger than the size of the crystal cell, then the wave packet of the produced neutrino has essentially the same size as the wave packet of the electron. We investigate the suppression of neutrino oscillations at large distances caused by two mechanisms: (1) spatial separation of wave packets corresponding to different neutrino masses; (2) neutrino energy dispersion for given neutrino mass eigenstates. We resolve the contributions of these two mechanisms. (orig.)

  14. Thought Suppression Research Methods: Paradigms, Theories, Methodological Concerns

    Directory of Open Access Journals (Sweden)

    Niczyporuk Aneta

    2016-12-01

    Full Text Available It is hard to provide an unequivocal answer to the question of whether or not thought suppression is effective. Two thought suppression paradigms - the “white bear” paradigm and the think/no-think paradigm - give mixed results. Generally, “white bear” experiments indicate that thought suppression is counterproductive, while experiments in the think/no-think paradigm suggest that it is possible to effectively suppress a thought. There are also alternative methods used to study thought suppression, for instance the directed forgetting paradigm or the Stroop task. In the article, I describe the research methods used to explore thought suppression efficacy. I focus on the “white bear” and the think/no-think paradigms and discuss theories proposed to explain the results obtained. I also consider the internal and external validity of the methods used.

  15. Memory guidance in distractor suppression is governed by the availability of cognitive control.

    Science.gov (United States)

    Wen, Wen; Hou, Yin; Li, Sheng

    2018-03-26

    Information stored in the memory systems can affect visual search. Previous studies have shown that holding the to-be-ignored features of distractors in working memory (WM) could accelerate target selection. However, such facilitation effect was only observed when the cued to-be-ignored features remained unchanged within an experimental block (i.e., the fixed cue condition). No search benefit was obtained if the to-be-ignored features varied from trial to trial (i.e., the varied cue condition). In the present study, we conducted three behavioral experiments to investigate whether the WM and long-term memory (LTM) representations of the to-be-ignored features could facilitate visual search in the fixed cue (Experiment 1) and varied cue (Experiments 2 and 3) conditions. Given the importance of the processing time of cognitive control in distractor suppression, we divided visual search trials into five quintiles based on their reaction times (RTs) and examined the temporal characteristics of the suppression effect. Results showed that both the WM and LTM representations of the to-be-ignored features could facilitate distractor suppression in the fixed cue condition, and the facilitation effects were evident across the quintiles in the RT distribution. However, in the varied cue condition, the RT benefits of the WM-matched distractors occurred only in the trials with the longest RTs, whereas no advantage of the LTM-matched distractors was observed. These results suggest that the effective WM-guided distractor suppression depends on the availability of cognitive control and the LTM-guided suppression occurs only if sufficient WM resource is accessible by LTM reactivation.

  16. Suppressive effects of ketamine on macrophage functions

    International Nuclear Information System (INIS)

    Chang Yi; Chen, T.-L.; Sheu, J.-R.; Chen, R.-M.

    2005-01-01

    Ketamine is an intravenous anesthetic agent. Clinically, induction of anesthesia with ketamine can cause immunosuppression. Macrophages play important roles in host defense. In this study, we attempted to evaluate the effects of ketamine on macrophage functions and its possible mechanism using mouse macrophage-like Raw 264.7 cells as the experimental model. Exposure of macrophages to 10 and 100 μM ketamine, which correspond to 0.1 and 1 times the clinically relevant concentration, for 1, 6, and 24 h had no effect on cell viability or lactate dehydrogenase release. When the administered concentration reached 1000 μM, ketamine caused a release of lactate dehydrogenase and cell death. Ketamine, at 10 and 100 μM, did not affect the chemotactic activity of macrophages. Administration of 1000 μM ketamine in macrophages resulted in a decrease in cell migration. Treatment of macrophages with ketamine reduced phagocytic activities. The oxidative ability of macrophages was suppressed by ketamine. Treatment with lipopolysaccharide induced TNF-α, IL-1β, and IL-6 mRNA in macrophages. Administration of ketamine alone did not influence TNF-α, IL-1β, or IL-6 mRNA production. Meanwhile, cotreatment with ketamine and lipopolysaccharide significantly inhibited lipopolysaccharide-induced TNF-α, IL-1β, and IL-6 mRNA levels. Exposure to ketamine led to a decrease in the mitochondrial membrane potential. However, the activity of mitochondrial complex I NADH dehydrogenase was not affected by ketamine. This study shows that a clinically relevant concentration of ketamine (100 μM) can suppress macrophage function of phagocytosis, its oxidative ability, and inflammatory cytokine production possibly via reduction of the mitochondrial membrane potential instead of direct cellular toxicity

  17. Rituximab selectively suppresses specific islet antibodies.

    Science.gov (United States)

    Yu, Liping; Herold, Kevan; Krause-Steinrauf, Heidi; McGee, Paula L; Bundy, Brian; Pugliese, Alberto; Krischer, Jeff; Eisenbarth, George S

    2011-10-01

    The TrialNet Study Group evaluated rituximab, a B-cell-depleting monoclonal antibody, for its effect in new-onset patients with type 1A diabetes. Rituximab decreased the loss of C-peptide over the first year of follow-up and markedly depleted B lymphocytes for 6 months after administration. This article analyzes the specific effect of rituximab on multiple islet autoantibodies. A total of 87 patients between the ages of 8 and 40 years received either rituximab or a placebo infusion weekly for four doses close to the onset of diabetes. Autoantibodies to insulin (IAAs), GAD65 (GADAs), insulinoma-associated protein 2 (IA2As), and ZnT8 (ZnT8As) were measured with radioimmunoassays. The primary outcome for this autoantibody analysis was the mean level of autoantibodies during follow-up. Rituximab markedly suppressed IAAs compared with the placebo injection but had a much smaller effect on GADAs, IA2As, and ZnT8As. A total of 40% (19 of 48) of rituximab-treated patients who were IAA positive became IAA negative versus 0 of 29 placebo-treated patients (P 1 year in insulin-treated patients. For the patients receiving insulin for >2 weeks prior to rituximab administration, we cannot assess whether rituximab not only blocks the acquisition of insulin antibodies induced by insulin administration and/or also suppresses preformed insulin autoantibodies. Studies in prediabetic non-insulin-treated patients will likely be needed to evaluate the specific effects of rituximab on levels of IAAs.

  18. Suppression of soil nitrification by plants.

    Science.gov (United States)

    Subbarao, Guntur Venkata; Yoshihashi, Tadashi; Worthington, Margaret; Nakahara, Kazuhiko; Ando, Yasuo; Sahrawat, Kanwar Lal; Rao, Idupulapati Madhusudhana; Lata, Jean-Christophe; Kishii, Masahiro; Braun, Hans-Joachim

    2015-04-01

    Nitrification, the biological oxidation of ammonium to nitrate, weakens the soil's ability to retain N and facilitates N-losses from production agriculture through nitrate-leaching and denitrification. This process has a profound influence on what form of mineral-N is absorbed, used by plants, and retained in the soil, or lost to the environment, which in turn affects N-cycling, N-use efficiency (NUE) and ecosystem health and services. As reactive-N is often the most limiting in natural ecosystems, plants have acquired a range of mechanisms that suppress soil-nitrifier activity to limit N-losses via N-leaching and denitrification. Plants' ability to produce and release nitrification inhibitors from roots and suppress soil-nitrifier activity is termed 'biological nitrification inhibition' (BNI). With recent developments in methodology for in-situ measurement of nitrification inhibition, it is now possible to characterize BNI function in plants. This review assesses the current status of our understanding of the production and release of biological nitrification inhibitors (BNIs) and their potential in improving NUE in agriculture. A suite of genetic, soil and environmental factors regulate BNI activity in plants. BNI-function can be genetically exploited to improve the BNI-capacity of major food- and feed-crops to develop next-generation production systems with reduced nitrification and N2O emission rates to benefit both agriculture and the environment. The feasibility of such an approach is discussed based on the progresses made. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Regorafenib suppresses sinusoidal obstruction syndrome in rats.

    Science.gov (United States)

    Okuno, Masayuki; Hatano, Etsuro; Nakamura, Kojiro; Miyagawa-Hayashino, Aya; Kasai, Yosuke; Nishio, Takahiro; Seo, Satoru; Taura, Kojiro; Uemoto, Shinji

    2015-02-01

    Sinusoidal obstruction syndrome (SOS), a form of drug-induced liver injury related to oxaliplatin treatment, is associated with postoperative morbidity after hepatectomy. This study aimed to examine the impact of regorafenib, the first small-molecule kinase inhibitor to show efficacy against metastatic colorectal cancer, on a rat model of SOS. Rats with monocrotaline (MCT)-induced SOS were divided into two groups according to treatment with either regorafenib (6 mg/kg) or vehicle alone, which were administered at 12 and 36 h, respectively, before MCT administration. Histopathologic examination and serum biochemistry tests were performed 48 h after MCT administration. Sinusoidal endothelial cells were evaluated by immunohistochemistry and electron microscopy. To examine whether regorafenib preserved remnant liver function, a 30% hepatectomy was performed in each group. The rats in the vehicle group displayed typical SOS features, whereas these features were suppressed in the regorafenib group. The total SOS scores were significantly lower in the regorafenib group than in the vehicle group. Immunohistochemistry and electron microscopy showed that regorafenib had a protective effect on sinusoidal endothelial cells. The postoperative survival rate after 7 d was significantly better in the regorafenib group than that in the vehicle group (26.7% versus 6.7%, P Regorafenib reduced the phosphorylation of extracellular signal-regulated kinase, which induced matrix metalloproteinase-9 (MMP-9) activation and decreased the activity of MMP-9, one of the crucial mediators of SOS development. Regorafenib suppressed MCT-induced SOS, concomitant with attenuating extracellular signal-regulated kinase phosphorylation, and MMP-9 activation, suggesting that regorafenib may be a favorable agent for use in combination with oxaliplatin-based chemotherapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Are Claims of Global Warming Being Suppressed?

    Science.gov (United States)

    Crowley, Thomas J.

    2006-02-01

    Over the last few years, I have heard many rumors that climate science relevant to the global warming discussion is being suppressed by the Bush Administration. One cannot do much about third-hand information. However, on 29 January, the New York Times published a front page article on NASA efforts to suppress statements about global warming by James Hansen, director of the NASA Goddard Institute for Space Studies. A claim by one government scientist, though, no matter how distinguished, still requires examples from other scientists before a general conclusion can be drawn about the overall scope of the problem. But if the charges are more widespread, then some government scientists might be reluctant to make such claims, because they might feel that their positions were jeopardized. Therefore, an alternate way may be needed to determine the scope of the issue, while still safeguarding government workers from possible retaliation. -On 30 January, Rep. Sherwood Boehlert (R-N.Y.), chairman of the U.S. House of Representatives Committee on Science, wrote a letter to NASA Administrator Michael Griffin addressing many of the concerns Crowley has raised. Boehlert wrote,``It ought to go without saying that government scientists must be free to describe their scientific conclusions and the implications of those conclusions to their fellow scientists, policymakers and the general public.'' He continued,``Good science cannot long persist in an atmosphere of intimidation. Political figures ought to be reviewing their public statements to make sure they are consistent with the best available science; scientists should not be reviewing their statements to make sure they are consistent with the current political orthodoxy.'' I commend Rep. Boehlert for his quick and clear statement of the importance of unfettered communication of science. -FRED SPILHAUS, Editor

  1. SUPPRESSION OF STAR FORMATION IN NGC 1266

    Energy Technology Data Exchange (ETDEWEB)

    Alatalo, Katherine; Lanz, Lauranne; Bitsakis, Theodoros; Appleton, Philip N.; Ogle, Patrick M. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Lacy, Mark; Lonsdale, Carol J. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Nyland, Kristina; Meier, David S. [Physics Department, New Mexico Tech, Socorro, NM 87801 (United States); Cales, Sabrina L. [Department of Astronomy, Faculty of Physical and Mathematical Sciences, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Chang, Philip [Department of Physics, University of Wisconsin—Milwaukee, Milwaukee, WI 53201 (United States); Davis, Timothy A.; De Zeeuw, P. T. [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching (Germany); Martín, Sergio, E-mail: kalatalo@ipac.caltech.edu [Institut de Radioastronomie Millimétrique, 300 Rue de la Piscine, Domaine Universitaire, F-38406 Saint Martin d' Hères (France)

    2015-01-01

    NGC 1266 is a nearby lenticular galaxy that harbors a massive outflow of molecular gas powered by the mechanical energy of an active galactic nucleus (AGN). It has been speculated that such outflows hinder star formation (SF) in their host galaxies, providing a form of feedback to the process of galaxy formation. Previous studies, however, indicated that only jets from extremely rare, high-power quasars or radio galaxies could impart significant feedback on their hosts. Here we present detailed observations of the gas and dust continuum of NGC 1266 at millimeter wavelengths. Our observations show that molecular gas is being driven out of the nuclear region at M-dot {sub out}≈110 M{sub ⊙} yr{sup –1}, of which the vast majority cannot escape the nucleus. Only 2 M {sub ☉} yr{sup –1} is actually capable of escaping the galaxy. Most of the molecular gas that remains is very inefficient at forming stars. The far-infrared emission is dominated by an ultra-compact (≲ 50 pc) source that could either be powered by an AGN or by an ultra-compact starburst. The ratio of the SF surface density (Σ{sub SFR}) to the gas surface density (Σ{sub H{sub 2}}) indicates that SF is suppressed by a factor of ≈50 compared to normal star-forming galaxies if all gas is forming stars, and ≈150 for the outskirt (98%) dense molecular gas if the central region is powered by an ultra-compact starburst. The AGN-driven bulk outflow could account for this extreme suppression by hindering the fragmentation and gravitational collapse necessary to form stars through a process of turbulent injection. This result suggests that even relatively common, low-power AGNs are able to alter the evolution of their host galaxies as their black holes grow onto the M-σ relation.

  2. Sunspot Light Walls Suppressed by Nearby Brightenings

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Shuhong; Zhang, Jun; Hou, Yijun; Li, Xiaohong [CAS Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Erdélyi, Robertus [Solar Physics and Space Plasma Research Centre, School of Mathematics and Statistics, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Yan, Limei, E-mail: shuhongyang@nao.cas.cn [Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029 (China)

    2017-07-01

    Light walls, as ensembles of oscillating bright structures rooted in sunspot light bridges, have not been well studied, although they are important for understanding sunspot properties. Using the Interface Region Imaging Spectrograph and Solar Dynamics Observatory observations, here we study the evolution of two oscillating light walls each within its own active region (AR). The emission of each light wall decays greatly after the appearance of adjacent brightenings. For the first light wall, rooted within AR 12565, the average height, amplitude, and oscillation period significantly decrease from 3.5 Mm, 1.7 Mm, and 8.5 minutes to 1.6 Mm, 0.4 Mm, and 3.0 minutes, respectively. For the second light wall, rooted within AR 12597, the mean height, amplitude, and oscillation period of the light wall decrease from 2.1 Mm, 0.5 Mm, and 3.0 minutes to 1.5 Mm, 0.2 Mm, and 2.1 minutes, respectively. Particularly, a part of the second light wall even becomes invisible after the influence of a nearby brightening. These results reveal that the light walls are suppressed by nearby brightenings. Considering the complex magnetic topology in light bridges, we conjecture that the fading of light walls may be caused by a drop in the magnetic pressure, where the flux is canceled by magnetic reconnection at the site of the nearby brightening. Another hypothesis is that the wall fading is due to the suppression of driver source ( p -mode oscillation), resulting from the nearby avalanche of downward particles along reconnected brightening loops.

  3. Perceptual Color Space Representations in the Oculomotor System Are Modulated by Surround Suppression and Biased Selection

    Directory of Open Access Journals (Sweden)

    Devin H. Kehoe

    2018-01-01

    Full Text Available The oculomotor system utilizes color extensively for planning saccades. Therefore, we examined how the oculomotor system actually encodes color and several factors that modulate these representations: attention-based surround suppression and inherent biases in selecting and encoding color categories. We measured saccade trajectories while human participants performed a memory-guided saccade task with color targets and distractors and examined whether oculomotor target selection processing was functionally related to the CIE (x,y color space distances between color stimuli and whether there were hierarchical differences between color categories in the strength and speed of encoding potential saccade goals. We observed that saccade planning was modulated by the CIE (x,y distances between stimuli thus demonstrating that color is encoded in perceptual color space by the oculomotor system. Furthermore, these representations were modulated by (1 cueing attention to a particular color thereby eliciting surround suppression in oculomotor color space and (2 inherent selection and encoding biases based on color category independent of cueing and perceptual discriminability. Since surround suppression emerges from recurrent feedback attenuation of sensory projections, observing oculomotor surround suppression suggested that oculomotor encoding of behavioral relevance results from integrating sensory and cognitive signals that are pre-attenuated based on task demands and that the oculomotor system therefore does not functionally contribute to this process. Second, although perceptual discriminability did partially account for oculomotor processing differences between color categories, we also observed preferential processing of the red color category across various behavioral metrics. This is consistent with numerous previous studies and could not be simply explained by perceptual discriminability. Since we utilized a memory-guided saccade task, this

  4. Perceptual Color Space Representations in the Oculomotor System Are Modulated by Surround Suppression and Biased Selection.

    Science.gov (United States)

    Kehoe, Devin H; Rahimi, Maryam; Fallah, Mazyar

    2018-01-01

    The oculomotor system utilizes color extensively for planning saccades. Therefore, we examined how the oculomotor system actually encodes color and several factors that modulate these representations: attention-based surround suppression and inherent biases in selecting and encoding color categories. We measured saccade trajectories while human participants performed a memory-guided saccade task with color targets and distractors and examined whether oculomotor target selection processing was functionally related to the CIE ( x , y ) color space distances between color stimuli and whether there were hierarchical differences between color categories in the strength and speed of encoding potential saccade goals. We observed that saccade planning was modulated by the CIE ( x , y ) distances between stimuli thus demonstrating that color is encoded in perceptual color space by the oculomotor system. Furthermore, these representations were modulated by (1) cueing attention to a particular color thereby eliciting surround suppression in oculomotor color space and (2) inherent selection and encoding biases based on color category independent of cueing and perceptual discriminability. Since surround suppression emerges from recurrent feedback attenuation of sensory projections, observing oculomotor surround suppression suggested that oculomotor encoding of behavioral relevance results from integrating sensory and cognitive signals that are pre-attenuated based on task demands and that the oculomotor system therefore does not functionally contribute to this process. Second, although perceptual discriminability did partially account for oculomotor processing differences between color categories, we also observed preferential processing of the red color category across various behavioral metrics. This is consistent with numerous previous studies and could not be simply explained by perceptual discriminability. Since we utilized a memory-guided saccade task, this indicates that

  5. Temporal suppression and augmentation of click-evoked otoacoustic emissions

    DEFF Research Database (Denmark)

    Verhulst, Sarah; Harte, James; Dau, Torsten

    2008-01-01

    This study investigates temporal suppression of click-evoked otoacoustic emissions (CEOAEs), occurring when a suppressor-click is presented close in time to a test-click (e.g. 0-8ms). Various temporal suppression methods for examining temporal changes in cochlear compression were evaluated and me...... under test. Temporal suppression was shown to be comparable for CEOAEs and SSOAEs, indicating similar underlying cochlear nonlinear mechanisms. This study contributes to a better understanding of the temporal properties of cochlear dynamics....

  6. Social Hierarchy and Depression: The Role of Emotion Suppression

    OpenAIRE

    Langner, Carrie A.; Epel, Elissa; Matthews, Karen; Moskowitz, Judith T.; Adler, Nancy

    2012-01-01

    Position in the social hierarchy is a major determinant of health outcomes. We examined the associations between aspects of social hierarchy and depressive symptoms with a specific focus on one potential psychological mechanism: emotion suppression. Suppressing negative emotion has mental health costs, but individuals with low social power and low social status may use these strategies to avoid conflict. Study 1 assessed perceived social power, tendency to suppress negative emotion, and depre...

  7. Psychophysical research progress of interocular suppression in amblyopic visual system

    OpenAIRE

    Jing-Jing Li; Yi Huang

    2016-01-01

    Some recent animal experiments and psychophysical studies indicate that patients with amblyopia have a structurally intact binocular visual system that is rendered functionally monocular due to suppression, and interocular suppression is a key mechanism in visual deficits experienced by patients with amblyopia. The aim of this review is to provide an overview of recent psychophysical findings that have investigated the important role of interocular suppression in amblyopia, the measurement an...

  8. Binocular vision in amblyopia : structure, suppression and plasticity

    OpenAIRE

    Hess, Robert F; Thompson, Benjamin; Baker, Daniel Hart

    2014-01-01

    The amblyopic visual system was once considered to be structurally monocular. However, it now evident that the capacity for binocular vision is present in many observers with amblyopia. This has led to new techniques for quantifying suppression that have provided insights into the relationship between suppression and the monocular and binocular visual deficits experienced by amblyopes. Furthermore, new treatments are emerging that directly target suppressive interactions within the visual cor...

  9. Acute Stress Suppresses Synaptic Inhibition and Increases Anxiety via Endocannabinoid Release in the Basolateral Amygdala.

    Science.gov (United States)

    Di, Shi; Itoga, Christy A; Fisher, Marc O; Solomonow, Jonathan; Roltsch, Emily A; Gilpin, Nicholas W; Tasker, Jeffrey G

    2016-08-10

    Stress and glucocorticoids stimulate the rapid mobilization of endocannabinoids in the basolateral amygdala (BLA). Cannabinoid receptors in the BLA contribute to anxiogenesis and fear-memory formation. We tested for rapid glucocorticoid-induced endocannabinoid regulation of synaptic inhibition in the rat BLA. Glucocorticoid application to amygdala slices elicited a rapid, nonreversible suppression of spontaneous, but not evoked, GABAergic synaptic currents in BLA principal neurons; the effect was also seen with a membrane-impermeant glucocorticoid, but not with intracellular glucocorticoid application, implicating a membrane-associated glucocorticoid receptor. The glucocorticoid suppression of GABA currents was not blocked by antagonists of nuclear corticosteroid receptors, or by inhibitors of gene transcription or protein synthesis, but was blocked by inhibiting postsynaptic G-protein activity, suggesting a postsynaptic nongenomic steroid signaling mechanism that stimulates the release of a retrograde messenger. The rapid glucocorticoid-induced suppression of inhibition was prevented by blocking CB1 receptors and 2-arachidonoylglycerol (2-AG) synthesis, and it was mimicked and occluded by CB1 receptor agonists, indicating it was mediated by the retrograde release of the endocannabinoid 2-AG. The rapid glucocorticoid effect in BLA neurons in vitro was occluded by prior in vivo acute stress-induced, or prior in vitro glucocorticoid-induced, release of endocannabinoid. Acute stress also caused an increase in anxiety-like behavior that was attenuated by blocking CB1 receptor activation and inhibiting 2-AG synthesis in the BLA. Together, these findings suggest that acute stress causes a long-lasting suppression of synaptic inhibition in BLA neurons via a membrane glucocorticoid receptor-induced release of 2-AG at GABA synapses, which contributes to stress-induced anxiogenesis. We provide a cellular mechanism in the basolateral amygdala (BLA) for the rapid stress

  10. Psychological behaviorism and behaviorizing psychology

    Science.gov (United States)

    Staats, Arthur W.

    1994-01-01

    Paradigmatic or psychological behaviorism (PB), in a four-decade history of development, has been shaped by its goal, the establishment of a behaviorism that can also serve as the approach in psychology (Watson's original goal). In the process, PB has become a new generation of behaviorism with abundant heuristic avenues for development in theory, philosophy, methodology, and research. Psychology has resources, purview and problem areas, and nascent developments of many kinds, gathered in chaotic diversity, needing unification (and other things) that cognitivism cannot provide. Behaviorism can, within PB's multilevel framework for connecting and advancing both psychology and behaviorism. PMID:22478175

  11. Temporal suppression and augmentation of click-evoked otoacoustic emissions

    DEFF Research Database (Denmark)

    Verhulst, Sarah; Harte, James; Dau, Torsten

    2008-01-01

    This study investigates and models temporal suppression of click-evoked otoacoustic emissions (CEOAEs). This suppression-effect is created when a suppressor-click is presented close in time to a test-click. The analysis was carried out for short time-frames of short- and long-latency CEOAEs...... suppression is present in all CEOAEs for inter-click intervals (ICIs) less than 8 ms. The long-latency CEOAEs showed augmentation (i.e., negative suppression) for ICIs of 6-7 ms which was not reported for the short-latency CEOAE at these ICIs. A phenomenological approach is adopted here to explain both...

  12. Electronic Warfare: Comprehensive Strategy Needed for Suppressing Enemy Air Defenses

    National Research Council Canada - National Science Library

    2001-01-01

    .... To achieve this suppression, the services use specialized aircraft designed to neutralize, destroy, or temporarily degrade enemy air defense systems through either physical attack or electronic warfare...

  13. Disease Suppressive Soils: New Insights from the Soil Microbiome.

    Science.gov (United States)

    Schlatter, Daniel; Kinkel, Linda; Thomashow, Linda; Weller, David; Paulitz, Timothy

    2017-11-01

    Soils suppressive to soilborne pathogens have been identified worldwide for almost 60 years and attributed mainly to suppressive or antagonistic microorganisms. Rather than identifying, testing and applying potential biocontrol agents in an inundative fashion, research into suppressive soils has attempted to understand how indigenous microbiomes can reduce disease, even in the presence of the pathogen, susceptible host, and favorable environment. Recent advances in next-generation sequencing of microbiomes have provided new tools to reexamine and further characterize the nature of these soils. Two general types of suppression have been described: specific and general suppression, and theories have been developed around these two models. In this review, we will present three examples of currently-studied model systems with features representative of specific and general suppressiveness: suppression to take-all (Gaeumannomyces graminis var. tritici), Rhizoctonia bare patch of wheat (Rhizoctonia solani AG-8), and Streptomyces. To compare and contrast the two models of general versus specific suppression, we propose a number of hypotheses about the nature and ecology of microbial populations and communities of suppressive soils. We outline the potential and limitations of new molecular techniques that can provide novel ways of testing these hypotheses. Finally, we consider how this greater understanding of the phytobiome can facilitate sustainable disease management in agriculture by harnessing the potential of indigenous soil microbes.

  14. Double suppression of FCNCs in a supersymmetric model

    International Nuclear Information System (INIS)

    Kajiyama, Yuji

    2004-01-01

    A concrete model which can suppress FCNCs and CP violating phenomena is suggested. It is S 3 symmetric extension of MSSM in extra dimensions where only SU(2) and SU(3) gauge multiplet are assumed to propagate in the bulk. They are suppressed due to S 3 flavor symmetry at M SUSY , and the infrared attractive force of gauge interaction in extra dimensions are used to suppress them at the compactification scale. We find that O(1) disorders of the soft parameters are allowed at the cut-off scale to suppress FCNCs and CP violating phenomena. (author)

  15. Double suppression of FCNCs in a supersymmetric model

    Energy Technology Data Exchange (ETDEWEB)

    Kajiyama, Yuji [Kanazawa Univ., Dept. of Physics, Kanazawa, Ishikawa (Japan)

    2004-12-01

    A concrete model which can suppress FCNCs and CP violating phenomena is suggested. It is S{sub 3} symmetric extension of MSSM in extra dimensions where only SU(2) and SU(3) gauge multiplet are assumed to propagate in the bulk. They are suppressed due to S{sub 3} flavor symmetry at M{sub SUSY}, and the infrared attractive force of gauge interaction in extra dimensions are used to suppress them at the compactification scale. We find that O(1) disorders of the soft parameters are allowed at the cut-off scale to suppress FCNCs and CP violating phenomena. (author)

  16. The regional extent of suppression: strabismics versus nonstrabismics.

    Science.gov (United States)

    Babu, Raiju Jacob; Clavagnier, Simon R; Bobier, William; Thompson, Benjamin; Hess, Robert F

    2013-10-09

    Evidence is accumulating that suppression may be the cause of amblyopia rather than a secondary consequence of mismatched retinal images. For example, treatment interventions that target suppression may lead to better binocular and monocular outcomes. Furthermore, it has recently been demonstrated that the measurement of suppression may have prognostic value for patching therapy. For these reasons, the measurement of suppression in the clinic needs to be improved beyond the methods that are currently available, which provide a binary outcome. We describe a novel quantitative method for measuring the regional extent of suppression that is suitable for clinical use. The method involves a dichoptic perceptual matching procedure at multiple visual field locations. We compare a group of normal controls (mean age: 28 ± 5 years); a group with strabismic amblyopia (four with microesotropia, five with esotropia, and one with exotropia; mean age: 35 ± 10 years); and a group with nonstrabismic anisometropic amblyopia (mean age: 33 ± 12 years). The extent and magnitude of suppression was similar for observers with strabismic and nonstrabismic amblyopia. Suppression was strongest within the central field and extended throughout the 20° field that we measured. Suppression extends throughout the central visual field in both strabismic and anisometropic forms of amblyopia. The strongest suppression occurs within the region of the visual field corresponding to the fovea of the fixing eye.

  17. Sal-like 4 (SALL4) suppresses CDH1 expression and maintains cell dispersion in basal-like breast cancer.

    Science.gov (United States)

    Itou, Junji; Matsumoto, Yoshiaki; Yoshikawa, Kiyotsugu; Toi, Masakazu

    2013-09-17

    In cell cultures, the dispersed phenotype is indicative of the migratory ability. Here we characterized Sal-like 4 (SALL4) as a dispersion factor in basal-like breast cancer. Our shRNA-mediated SALL4 knockdown system and SALL4 overexpression system revealed that SALL4 suppresses the expression of adhesion gene CDH1, and positively regulates the CDH1 suppressor ZEB1. Cell behavior analyses showed that SALL4 suppresses intercellular adhesion and maintains cell motility after cell-cell interaction and cell division, which results in the dispersed phenotype. Our findings indicate that SALL4 functions to suppress CDH1 expression and to maintain cell dispersion in basal-like breast cancer. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  18. Breaking continuous flash suppression: A new measure of unconscious processing during interocular suppression?

    Directory of Open Access Journals (Sweden)

    Timo eStein

    2011-12-01

    Full Text Available Until recently, it has been thought that under interocular suppression high-level visual processing is strongly inhibited if not abolished. With the development of continuous flash suppression (CFS, a variant of binocular rivalry, this notion has now been challenged by a number of reports showing that even high-level aspects of visual stimuli, such as familiarity, affect the time stimuli need to overcome CFS and emerge into awareness. In this breaking CFS (b-CFS paradigm, differential unconscious processing during suppression is inferred when (a speeded detection responses to initially invisible stimuli differ, and (b no comparable differences are found in non-rivalrous control conditions supposed to measure general threshold differences between stimuli. To critically evaluate these assumptions was the aim of the present study. In six experiments we compared the time upright and inverted faces needed to be detected. We found that not only under CFS, but also in control conditions upright faces were detected faster and more accurately than inverted faces, although the effect was larger during CFS. However, reaction time (RT distributions indicated critical differences between the CFS and the control condition. When RT distributions were matched, similar effect sizes were obtained in both conditions. Moreover, subjective ratings revealed that CFS and control conditions are not perceptually comparable. These findings cast doubt on the usefulness of non-rivalrous control conditions to rule out mere detection threshold differences as a cause of shorter detection latencies during CFS. In conclusion, we acknowledge that the b-CFS paradigm can be fruitfully applied as a highly sensitive device to probe differences between stimuli in their potency to gain access to awareness. However, our current findings suggest that such differences can not unequivocally be attributed to differential unconscious processing under interocular suppression.

  19. Electrocorticography and the early maturation of high-frequency suppression within the default mode network.

    Science.gov (United States)

    Weaver, Kurt E; Poliakov, Andrew; Novotny, Edward J; Olson, Jared D; Grabowski, Thomas J; Ojemann, Jeffrey G

    2018-02-01

    OBJECTIVE The acquisition and refinement of cognitive and behavioral skills during development is associated with the maturation of various brain oscillatory activities. Most developmental investigations have identified distinct patterns of low-frequency electrophysiological activity that are characteristic of various behavioral milestones. In this investigation, the authors focused on the cross-sectional developmental properties of high-frequency spectral power from the brain's default mode network (DMN) during goal-directed behavior. METHODS The authors contrasted regionally specific, time-evolving high gamma power (HGP) in the lateral DMN cortex between 3 young children (age range 3-6 years) and 3 adults by use of electrocorticography (ECoG) recordings over the left perisylvian cortex during a picture-naming task. RESULTS Across all participants, a nearly identical and consistent response suppression of HGP, which is a functional signature of the DMN, was observed during task performance recordings acquired from ECoG electrodes placed over the lateral DMN cortex. This finding provides evidence of relatively early maturation of the DMN. Furthermore, only HGP relative to evoked alpha and beta band power showed this level of consistency across all participants. CONCLUSIONS Regionally specific, task-evoked suppression of the high-frequency components of the cortical power spectrum is established early in brain development, and this response may reflect the early maturation of specific cognitive and/or computational mechanisms.

  20. Patterned changes in urge ratings with tic suppression in youth with chronic tic disorders.

    Science.gov (United States)

    Brabson, Laurel A; Brown, Jessica L; Capriotti, Matthew R; Ramanujam, Krishnapriya; Himle, Michael B; Nicotra, Cassandra M; Ostrander, Rick; Kelly, Laura M; Grados, Marco A; Walkup, John T; Perry-Parrish, Carisa; Reynolds, Elizabeth K; Hankinson, Jessica C; Specht, Matt W

    2016-03-01

    Premonitory urges are central to emerging behavioral models of chronic tic disorders (CTD). Urge reduction has been proposed as a behavioral explanation for tic maintenance and exacerbation as well as the efficacy of behavioral treatments. Prior investigations have produced inconsistent findings despite common methodologies. The current study evaluated the possibility that data aggregation obscures distinct and meaningful patterns of change in urge ratings when tics are freely expressed versus suppressed. Participants (n = 12) included children with moderate-to-marked tic severity and noticeable premonitory urges. Tic frequencies and urge ratings were obtained at 15 s and 10-s intervals, respectively, across an alternating sequence of 10-min tic freely and 40-min tic suppression conditions. Patterns were established using a two step approach. Five distinct patterns of urge rating change emerged, suggesting data aggregation may obscure meaningful patterns in the urge-tic relationship when tics are completed versus suppressed. Eligibility criteria may have unintentionally excluded younger affected children and included older participants with more severe tic disorders than commonly seen. Additional research with less stringent eligibility criteria and a larger sample size will help validate the results. The relationship between urges and tics is much more complex than previously theorized. Investigations that rely on global assessments of urge and tic severity and/or assume uniformity when aggregating participant data may obscure meaningful differences in the urge-tic relationship. Future investigations should examine the possibility that individual differences and/or developmental considerations modulate the functional urge-tic relationship. Copyright © 2015. Published by Elsevier Ltd.

  1. Recreating the Scene: An Effective Way to Provide Delayed Punishment for Inappropriate Motor Behavior.

    Science.gov (United States)

    Van Houten, Ron; Rolider, Ahmos

    1988-01-01

    A mediated punishment procedure that involved recreating a behavioral sequence by guiding the subject through the behavior in the situation in which it occurred was used to suppress several severe behavior problems in two severely handicapped children (ages 4 and 17). (Author/DB)

  2. Instructions to suppress semantic memory enhances or has no effect on P300 in a concealed information test (CIT).

    Science.gov (United States)

    Rosenfeld, J Peter; Ward, Anne; Drapekin, Jesse; Labkovsky, Elena; Tullman, Samuel

    2017-03-01

    The present study investigated the extent to which people can suppress semantic memory as indexed with the P300 ERP and the autobiographical implicit association test (aIAT). In EXP 1, participants (22) were run in a counterbalanced repeated measures study in both simply knowledgeable (SK) and knowledgeable with suppression (SP) conditions. A P300-based, concealed information test ("Complex Trial Protocol"; CTP) with a 50/50 Target/Nontarget (T/NT) ratio was given both with and without instructions to suppress semantic memories. The results showed increased P300s to probe name stimuli, reduced (but still high positive) aIAT d-scores, and increased simple reaction times to all stimuli used in ERP tests in the SP condition. EXP 2 was similar, but with SP and SK in two separate groups, and a 20/80 T/NT ratio. Again, ERP and aIAT results failed to show a suppression effect for semantic memory. The behavioral data suggest some task demand effects under suppression instructions, and that EXP 1 was more demanding than EXP 2. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Aggressive behavior

    NARCIS (Netherlands)

    Didden, H.C.M.; Lindsay, W.R.; Lang, R.B.; Sigafoos, J.; Deb, S.; Wiersma, J.; Peters-Scheffer, N.C.; Marschik, P.B.; O'Reilly, M.F.; Lancioni, G.E.; Singh, N.N.

    2016-01-01

    Aggressive behavior is common in individuals with intellectual and developmental disabilities (IDDs), and it is most often targeted for intervention. Psychological, contextual, and biological risk factors may contribute to the risk of aggressive behavior. Risk factors are gender (males), level of

  4. Suppression of tunnel modes of hydrogen in α-Mn by elastic stresses

    International Nuclear Information System (INIS)

    Antonov, V.E.; Fedotov, V.K.; Glazkov, V.P.; Somenkov, V.A.; Kozlenko, D.P.; Savenko, B.N.

    2002-01-01

    By means of inelastic incoherent scattering of neutrons one investigated into behavior of hydrogen tunnel mode in MnH 0.04 and MnH 0.07 under high pressure values in sapphire anvils. Peak of inelastic scattering relevant to hydrogen tunnelling in a two-hole potential was determined to vanish at 0.8 GPa pressure under quasi-hydrostatic mode and to survive with no visible changes under standard hydrostatics. The detected effect of suppression of tunnel modes by inhomogeneous elastic stresses is explained by interruption of levels in neighboring holes by static shifts [ru

  5. High rate of virological re-suppression among patients failing ...

    African Journals Online (AJOL)

    Results. Of 69 patients enrolled in the programme, 40 had at least one follow-up VL and no known drug resistance at enrolment; 27 (68%) of these re-suppressed while remaining on second-line ART following enhanced adherence support. The majority (18/27; 67%) achieved re-suppression within the first 3 months in the ...

  6. Thought Suppression and Meaning in Life: A Longitudinal Investigation

    Science.gov (United States)

    Krause, Neal

    2007-01-01

    The purpose of this study is to see if older adults who experience problems with thought suppression tend to encounter greater difficulty deriving a sense of meaning in life. Data from a longitudinal nationwide survey of older people (N = 988) indicate that greater difficulty with thought suppression is associated with a decline in meaning over…

  7. Burst-Suppression Ratio on Electrocorticography Depends on Interelectrode Distance

    DEFF Research Database (Denmark)

    Moldovan, Mihai; Calin, Alexandru; Kumaraswamy, Vishakhadatta M.

    2016-01-01

    Introduction: With deepening of anesthesia-induced comatose states, the EEG becomes fragmented by increasing periods of suppression. When measured from conventional EEG recordings, the binary burst-suppression signal (BS) appears similar across the scalp. As such, the BS ratio (BSR), quantifying...

  8. Regularized Adaptive Notch Filters for Acoustic Howling Suppression

    DEFF Research Database (Denmark)

    Gil-Cacho, Pepe; van Waterschoot, Toon; Moonen, Marc

    2009-01-01

    In this paper, a method for the suppression of acoustic howling is developed, based on adaptive notch filters (ANF) with regularization (RANF). The method features three RANFs working in parallel to achieve frequency tracking, howling detection and suppression. The ANF-based approach to howling...

  9. Social hierarchy and depression: the role of emotion suppression.

    Science.gov (United States)

    Langner, Carrie A; Epel, Elissa S; Matthews, Karen A; Moskowitz, Judith T; Adler, Nancy E

    2012-01-01

    Position in the social hierarchy is a major determinant of health outcomes. We examined the associations between aspects of social hierarchy and depressive symptoms with a specific focus on one potential psychological mechanism: emotion suppression. Suppressing negative emotion has mental health costs, but individuals with low social power and low social status may use these strategies to avoid conflict. Study 1 assessed perceived social power, tendency to suppress negative emotion, and depressive symptoms in a community sample of women. Low social power was related to greater depressive symptoms, and this relationship was partially mediated by emotion suppression. Study 2 examined education as a proxy for social hierarchy position, anger suppression, and depressive symptoms in a national, longitudinal cohort study (The coronary artery risk development in young adults [CARDIA] study; Cutter et al., 1991). Much as in study 1, low education levels were correlated with greater depressive symptoms, and this relationship was partially mediated by anger suppression. Further, suppression mediated the relationship between low education and subsequent depression up to 15 years later. These findings support the theory that social hierarchy affects mental health in part through a process of emotion suppression.

  10. Suppression of mouse-killing in rats following irradiation

    International Nuclear Information System (INIS)

    O'Boyle, M.

    1976-01-01

    Suppression of mouse-killing was produced following pairings of mouse-presentations (CS) with 96 roentgens of ionizing radiation (US) at 0 (less than 2 min.) and 30 min. US-CS interstimulus intervals. No suppression was found at CS-US intervals of 30 min., 1 hr., and 2 hr., or at US-CS intervals of 1 hr. and 2 hr

  11. How best to assess suppression in patients with high anisometropia.

    Science.gov (United States)

    Li, Jinrong; Hess, Robert F; Chan, Lily Y L; Deng, Daming; Chen, Xiang; Yu, Minbin; Thompson, Benjamin S

    2013-02-01

    We have recently described a rapid technique for measuring suppression using a dichoptic signal/noise task. Here, we report a modification of this technique that allows for accurate measurements to be made in amblyopic patients with high levels of anisometropia. This was necessary because aniseikonic image size differences between the two eyes can provide a cue for signal/noise segregation and, therefore, influence suppression measurement in these patients. Suppression was measured using our original technique and with a modified technique whereby the size of the signal and noise elements was randomized across the stimulus to eliminate size differences as a cue for task performance. Eleven patients with anisometropic amblyopia, five with more than 5 diopters (D) spherical equivalent difference (SED), six with less than 5 D SED between the eyes, and 10 control observers completed suppression measurements using both techniques. Suppression measurements in controls and patients with less than 5 D SED were constant across the two techniques; however, patients with more than 5 D SED showed significantly stronger suppression on the modified technique with randomized element size. Measurements made with the modified technique correlated with the loss of visual acuity in the amblyopic eye and were in good agreement with previous reports using detailed psychophysical measurements. The signal/noise technique for measuring suppression can be applied to patients with high levels of anisometropia and aniseikonia if element size is randomized. In addition, deeper suppression is associated with a greater loss of visual acuity in patients with anisometropic amblyopia.

  12. Improved fat suppression of the breast using discretized frequency shimming

    NARCIS (Netherlands)

    van der Velden, Tijl A.; Luijten, Peter R.; Klomp, DWJ

    2018-01-01

    Purpose: Robust fat suppression is essential in bilateral breast MRI at 7 Tesla. The lack of good fat suppression can result in errors when calculating the enhancement curve from dynamic contrast-enhanced acquisitions. In this work we propose discretized frequency shimming to improve the quality of

  13. Continuous Flash Suppression: Stimulus Fractionation rather than Integration.

    Science.gov (United States)

    Moors, Pieter; Hesselmann, Guido; Wagemans, Johan; van Ee, Raymond

    2017-10-01

    Recent studies using continuous flash suppression suggest that invisible stimuli are processed as integrated, semantic entities. We challenge the viability of this account, given recent findings on the neural basis of interocular suppression and replication failures of high-profile CFS studies. We conclude that CFS reveals stimulus fractionation in visual cortex. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Eye Contact Facilitates Awareness of Faces during Interocular Suppression

    Science.gov (United States)

    Stein, Timo; Senju, Atsushi; Peelen, Marius V.; Sterzer, Philipp

    2011-01-01

    Eye contact captures attention and receives prioritized visual processing. Here we asked whether eye contact might be processed outside conscious awareness. Faces with direct and averted gaze were rendered invisible using interocular suppression. In two experiments we found that faces with direct gaze overcame such suppression more rapidly than…

  15. Nature of dynamical suppressions in the generalized Veneziano model

    International Nuclear Information System (INIS)

    Odorico, R.

    1976-05-01

    It is shown by explicit numerical calculations that of a class of coupling suppressions existing in the generalized Veneziano model, which have been recently used to interpret the psi data and other related phenomena, only a part can be attributed to the exponential growth with energy of the number of levels in the model. The remaining suppressions have a more direct dual origin

  16. A dual purpose Compton suppression spectrometer

    CERN Document Server

    Parus, J; Raab, W; Donohue, D

    2003-01-01

    A gamma-ray spectrometer with a passive and an active shield is described. It consists of a HPGe coaxial detector of 42% efficiency and 4 NaI(Tl) detectors. The energy output pulses of the Ge detector are delivered into the 3 spectrometry chains giving the normal, anti- and coincidence spectra. From the spectra of a number of sup 1 sup 3 sup 7 Cs and sup 6 sup 0 Co sources a Compton suppression factor, SF and a Compton reduction factor, RF, as the parameters characterizing the system performance, were calculated as a function of energy and source activity and compared with those given in literature. The natural background is reduced about 8 times in the anticoincidence mode of operation, compared to the normal spectrum which results in decreasing the detection limits for non-coincident gamma-rays up to a factor of 3. In the presence of other gamma-ray activities, in the range from 5 to 11 kBq, non- and coincident, the detection limits can be decreased for some nuclides by a factor of 3 to 5.7.

  17. Is neutrinoless double beta decay suppressed

    International Nuclear Information System (INIS)

    Tomoda, T.

    1989-01-01

    Much effort has been devoted to the study of nuclear double beta decay, since the observation of a neutrinoless double beta (OνΒΒ) decay would be clear evidence that the electron neutrino is a Majorana particle. The OνΒΒ decay is caused by a finite Majorana neutrino mass and/or an admixture of right-handed leptonic currents. In order to relate these quantities to OνΒΒ decay rates, we need nuclear matrix elements, which are model dependent. One of the possibilities of testing nuclear models employed in such analysis is to calculate the experimentally known rates of ΒΒ decay with emission of two neutrinos (2νΒΒ decay) which occurs independently of the nature of the neutrino. There was a long-standing difficulty in such attempts that the calculated 2νΒΒ decay rates turned out to be always too large by one to two orders of magnitude. Trying to overcome such difficulty, Klapdor and Grotz as well as Vogel and Zirnbauer showed in their calculation using schematic effective interactions such that 2νΒΒ decay rates can get reduced considerably due to the nuclear ground state correlations. This paper reports that the suppression is ascribed to that of the virtual Gamow-Teller transitions from the excited 1 + states of the intermediate odd-odd -even nucleus

  18. Myeloma cells suppress osteoblasts through sclerostin secretion

    Energy Technology Data Exchange (ETDEWEB)

    Colucci, S; Brunetti, G; Oranger, A [Department of Human Anatomy and Histology, University of Bari Medical School, Bari (Italy); Mori, G [Department of Biomedical Science, University of Foggia, Foggia (Italy); Sardone, F [Department of Human Anatomy and Histology, University of Bari Medical School, Bari (Italy); Specchia, G; Rinaldi, E; Curci, P; Liso, V [Department of Emergency and Organ Transplantation, Hematology Section, Bari University Medical School, Bari (Italy); Passeri, G [Department of Internal Medicine and Biomedical Sciences, Center for Metabolic Bone Diseases, University of Parma, Parma (Italy); Zallone, A [Department of Human Anatomy and Histology, University of Bari Medical School, Bari (Italy); Rizzi, R [Department of Emergency and Organ Transplantation, Hematology Section, Bari University Medical School, Bari (Italy); Grano, M [Department of Human Anatomy and Histology, University of Bari Medical School, Bari (Italy)

    2011-06-01

    Wingless-type (Wnt) signaling through the secretion of Wnt inhibitors Dickkopf1, soluble frizzled-related protein-2 and -3 has a key role in the decreased osteoblast (OB) activity associated with multiple myeloma (MM) bone disease. We provide evidence that another Wnt antagonist, sclerostin, an osteocyte-expressed negative regulator of bone formation, is expressed by myeloma cells, that is, human myeloma cell lines (HMCLs) and plasma cells (CD138+ cells) obtained from the bone marrow (BM) of a large number of MM patients with bone disease. We demonstrated that BM stromal cells (BMSCs), differentiated into OBs and co-cultured with HMCLs showed, compared with BMSCs alone, reduced expression of major osteoblastic-specific proteins, decreased mineralized nodule formation and attenuated the expression of members of the activator protein 1 transcription factor family (Fra-1, Fra-2 and Jun-D). Moreover, in the same co-culture system, the addition of neutralizing anti-sclerostin antibodies restored OB functions by inducing nuclear accumulation of β-catenin. We further demonstrated that the upregulation of receptor activator of nuclear factor κ-B ligand and the downregulation of osteoprotegerin in OBs were also sclerostin mediated. Our data indicated that sclerostin secretion by myeloma cells contribute to the suppression of bone formation in the osteolytic bone disease associated to MM.

  19. Glutamine supplementation suppresses herpes simplex virus reactivation.

    Science.gov (United States)

    Wang, Kening; Hoshino, Yo; Dowdell, Kennichi; Bosch-Marce, Marta; Myers, Timothy G; Sarmiento, Mayra; Pesnicak, Lesley; Krause, Philip R; Cohen, Jeffrey I

    2017-06-30

    Chronic viral infections are difficult to treat, and new approaches are needed, particularly those aimed at reducing reactivation by enhancing immune responses. Herpes simplex virus (HSV) establishes latency and reactivates frequently, and breakthrough reactivation can occur despite suppressive antiviral therapy. Virus-specific T cells are important to control HSV, and proliferation of activated T cells requires increased metabolism of glutamine. Here, we found that supplementation with oral glutamine reduced virus reactivation in latently HSV-1-infected mice and HSV-2-infected guinea pigs. Transcriptome analysis of trigeminal ganglia from latently HSV-1-infected, glutamine-treated WT mice showed upregulation of several IFN-γ-inducible genes. In contrast to WT mice, supplemental glutamine was ineffective in reducing the rate of HSV-1 reactivation in latently HSV-1-infected IFN-γ-KO mice. Mice treated with glutamine also had higher numbers of HSV-specific IFN-γ-producing CD8 T cells in latently infected ganglia. Thus, glutamine may enhance the IFN-γ-associated immune response and reduce the rate of reactivation of latent virus infection.

  20. Installation for the suppression of sodium fires

    International Nuclear Information System (INIS)

    Newman, R.N.; Payne, J.F.B.; Lee, C.J.; Rowe, D.M.J.

    1979-01-01

    The basic operating principles are discussed of a passive baffle-catch tray fire suppression system for sodium fires. A new design is described incorporating increased compartmentalization of the collecting and drainage parts of the device. The burning and smoke generation rates from trays with varying aperture sizes were measured. From the experiments it was found that the burning rate and smoke generation rates could be related satisfactorily to the aperture areas. For the smallest aperture size ( 2 ) it was found that the smoke release was considerably less than that from a fire of the same area, because the smoke deposited on the underside of the baffle. A re-ignition problem was found, where pillars of sodium oxide (wicks) grow upward from the surface of the drained sodium and begin to burn when level with the baffle aperature. From a knowledge of the rate of growth of the wicks, trays may be made sufficiently deep to avoid the problem. Self acting valves were developed which allow the passage of sodium through the aperture and close when drainage is complete. These devices were shown to effect complete extinction of the drained sodium. Using the designs proposed it is possible to construct a system that will reduce the smoke emission from the drained sodium by a factor approaching 10 3 , without the use of valves, or with the self acting valves developed, reduce the emission from the drained sodium to approximately zero. (author)

  1. Rotator cuff injury: fat suppression MR image

    International Nuclear Information System (INIS)

    Won, Jong Yoon; Suh, Jin Suck; Park, Chang Yun; Lee, Yeon Hee; Kim, Yong Soo

    1994-01-01

    We performed the study prospectively to evaluate the advantage of fat suppression MR in the diagnosis of rotator cuff injury. Ten symptomatic patients were studied with both conventional T2WI and FST2WI using chemical shift technique. Each image was analyzed for the assessment of injuries, conspicuity of the lesion, the presence of effusion in subacromical bursae and joint space, and presence of humeral head injury. Arthroscopy was done in 4 patients following MRI. We could made presumptive diagnoses on FSMR as identical as on conventional MR in six cases(1 normal, 2 tendinitis, 2 partial thickness tear, 1 full thickness tear), two of them were confirmed by arthroscopic procedures. Two cases of partial thickness tear proved by arthroscopy were detected on FST2WI, whereas they were considered tendinitis on conventional T2WI. There were another 2 cases who showed tendinitis on FSMR, but normal on conventional T2WI. They, however, were not confirmed by either arthroscopy or surgical procedure. We found the FSMR were superior to conventional T2WI in the conspicuity of lesions and detection of joint effusion and abnormalities on the humeral head. We think FSMR of the shoulder could have significant diagnostic advantages over the conventional spin-echo MR imaging

  2. Probiotics-mediated suppression of cancer.

    Science.gov (United States)

    So, Stephanie S Y; Wan, Murphy L Y; El-Nezami, Hani

    2017-01-01

    Probiotics can be used as an adjuvant for cancer prevention or/and treatment through their abilities to modulate intestinal microbiota and host immune response. Although most of the recent reviews have focused on the potential role of probiotics against colon cancer, only few of them include the probiotic effect on extraintestinal cancers. The present review covers the most important findings from the literature published during the past 20 months (from January 2015 to August 2016) regarding the probiotics-mediated suppression of both gastrointestinal and extraintestinal cancers and the underlying mechanisms. A comprehensive literature search in Pubmed, Science direct and Google scholar databases was conducted to locate all relevant articles that investigated the effect of probiotics on prevention/treatment of both gastrointestinal and extraintestinal cancers. Different mechanisms for the beneficial effects of probiotics against cancer were also discussed, mainly via modulation of gut microbiota which thereby influences host metabolism and immunity. Despite laboratory-based studies having demonstrated encouraging outcomes that probiotics possess antitumor effects, the benefits should not be exaggerated before we get more results from human clinical trials. These are very important before the medical community can accept the use of probiotics as an alternative therapy for cancer control.

  3. Rotator cuff injury: fat suppression MR image

    Energy Technology Data Exchange (ETDEWEB)

    Won, Jong Yoon; Suh, Jin Suck; Park, Chang Yun; Lee, Yeon Hee [Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Yong Soo [Inje University College of Medicine, Busan (Korea, Republic of)

    1994-04-15

    We performed the study prospectively to evaluate the advantage of fat suppression MR in the diagnosis of rotator cuff injury. Ten symptomatic patients were studied with both conventional T2WI and FST2WI using chemical shift technique. Each image was analyzed for the assessment of injuries, conspicuity of the lesion, the presence of effusion in subacromical bursae and joint space, and presence of humeral head injury. Arthroscopy was done in 4 patients following MRI. We could made presumptive diagnoses on FSMR as identical as on conventional MR in six cases(1 normal, 2 tendinitis, 2 partial thickness tear, 1 full thickness tear), two of them were confirmed by arthroscopic procedures. Two cases of partial thickness tear proved by arthroscopy were detected on FST2WI, whereas they were considered tendinitis on conventional T2WI. There were another 2 cases who showed tendinitis on FSMR, but normal on conventional T2WI. They, however, were not confirmed by either arthroscopy or surgical procedure. We found the FSMR were superior to conventional T2WI in the conspicuity of lesions and detection of joint effusion and abnormalities on the humeral head. We think FSMR of the shoulder could have significant diagnostic advantages over the conventional spin-echo MR imaging.

  4. Suppression of PTEN transcription by UVA

    Science.gov (United States)

    Zhao, Baozhong; Ming, Mei; He, Yu-Ying

    2012-01-01

    Although UVA has different physical and biological targets than UVB, the contribution of UVA to skin cancer susceptibility and its molecular basis remain largely unknown. Here we show that chronic UVA radiation suppresses PTEN expression at the mRNA level. Subchronic and acute UVA radiation also down-regulated PTEN in normal human epidermal keratinocytes, skin culture and mouse skin. At the molecular level, chronic UVA radiation decreased the transcriptional activity of the PTEN promoter in a methylation-independent manner, while it had no effect on the protein stability or mRNA stability of PTEN. In contrast, we found that UVA-induced activation of the Ras/ERK/AKT and NF-κB pathways plays an important role in UV-induced PTEN down-regulation. Inhibiting ERK or AKT increases PTEN expression. Our findings may provide unique insights into PTEN down-regulation as a critical component of UVA’s molecular impact during keratinocyte transformation. PMID:23129115

  5. Pressure suppression device for nuclear reactor building

    International Nuclear Information System (INIS)

    Ikegame, Noboru.

    1992-01-01

    In a nuclear reactor building, there are disposed cooling coils connected to an air supply duct at the outside of the building, an air supply blower, an air supply duct having the top end opened, an exhaustion duct having the top end opened and a bypassing pipeline interposed between the exhaustion duct and the air supply duct on the side of the inlet of the cooling coils. In the reactor building, when a radioactive material leakage accident should occur, an isolation valve is closed to isolate the building from the outside. Further, bypassing isolation valve is opened to form a closed cooling circuit by the cooling coils, the air supply blower and the air supply duct, the exhaustion duct and the bypassing pipeline in the reactor building. With such a constitution, since air as the atmosphere in the building is circulated through the closed cooling circuit and cooled by the cooling coils, the temperature is not elevated. Accordingly, since the pressure elevation of the atmosphere in the building is suppressed, the atmosphere containing radioactive materials do not flow out of the building. (I.N.)

  6. Exploring genetic suppression interactions on a global scale.

    Science.gov (United States)

    van Leeuwen, Jolanda; Pons, Carles; Mellor, Joseph C; Yamaguchi, Takafumi N; Friesen, Helena; Koschwanez, John; Ušaj, Mojca Mattiazzi; Pechlaner, Maria; Takar, Mehmet; Ušaj, Matej; VanderSluis, Benjamin; Andrusiak, Kerry; Bansal, Pritpal; Baryshnikova, Anastasia; Boone, Claire E; Cao, Jessica; Cote, Atina; Gebbia, Marinella; Horecka, Gene; Horecka, Ira; Kuzmin, Elena; Legro, Nicole; Liang, Wendy; van Lieshout, Natascha; McNee, Margaret; San Luis, Bryan-Joseph; Shaeri, Fatemeh; Shuteriqi, Ermira; Sun, Song; Yang, Lu; Youn, Ji-Young; Yuen, Michael; Costanzo, Michael; Gingras, Anne-Claude; Aloy, Patrick; Oostenbrink, Chris; Murray, Andrew; Graham, Todd R; Myers, Chad L; Andrews, Brenda J; Roth, Frederick P; Boone, Charles

    2016-11-04

    Genetic suppression occurs when the phenotypic defects caused by a mutation in a particular gene are rescued by a mutation in a second gene. To explore the principles of genetic suppression, we examined both literature-curated and unbiased experimental data, involving systematic genetic mapping and whole-genome sequencing, to generate a large-scale suppression network among yeast genes. Most suppression pairs identified novel relationships among functionally related genes, providing new insights into the functional wiring diagram of the cell. In addition to suppressor mutations, we identified frequent secondary mutations,in a subset of genes, that likely cause a delay in the onset of stationary phase, which appears to promote their enrichment within a propagating population. These findings allow us to formulate and quantify general mechanisms of genetic suppression. Copyright © 2016, American Association for the Advancement of Science.

  7. Alcohol disinhibition of behaviors in C. elegans.

    Directory of Open Access Journals (Sweden)

    Stephen M Topper

    Full Text Available Alcohol has a wide variety of effects on physiology and behavior. One of the most well-recognized behavioral effects is disinhibition, where behaviors that are normally suppressed are displayed following intoxication. A large body of evidence has shown that alcohol-induced disinhibition in humans affects attention, verbal, sexual, and locomotor behaviors. Similar behavioral disinhibition is also seen in many animal models of ethanol response, from invertebrates to mammals and primates. Here we describe several examples of disinhibition in the nematode C. elegans. The nematode displays distinct behavioral states associated with locomotion (crawling on land and swimming in water that are mediated by dopamine. On land, animals crawl and feed freely, but these behaviors are inhibited in water. We found that additional behaviors, including a variety of escape responses are also inhibited in water. Whereas alcohol non-specifically impaired locomotion, feeding, and escape responses in worms on land, alcohol specifically disinhibited these behaviors in worms immersed in water. Loss of dopamine signaling relieved disinhibition of feeding behavior, while loss of the D1-like dopamine receptor DOP-4 impaired the ethanol-induced disinhibition of crawling. The powerful genetics and simple nervous system of C. elegans may help uncover conserved molecular mechanisms that underlie alcohol-induced disinhibition of behaviors in higher animals.

  8. Analysis and suppression of passive noise in surface microseismic data

    Science.gov (United States)

    Forghani-Arani, Farnoush

    the surface-wave arrivals. Interferometry is a powerful tool to extract waves (including body-wave and surface-waves) that propagate from any receiver in the array (called a pseudo source) to the other receivers across the array. Since most of the noise sources in surface microseismic data lie on the surface, seismic interferometry yields pseudo source gathers dominated by surface-wave energy. The dispersive characteristics of these surface-waves are important properties that can be used to extract information necessary for suppressing these waves. I demonstrate the application of interferometry to surface passive data recorded during the hydraulic fracturing operation of a tight gas reservoir and extract the dispersion properties of surface-waves corresponding to a pseudo-shot gather. Comparison of the dispersion characteristics of the surface waves from the pseudo-shot gather with that of an active shot-gather shows interesting similarities and differences. The dispersion character (e.g. velocity change with frequency) of the fundamental mode was observed to have the same behavior for both the active and passive data. However, for the higher mode surface-waves, the dispersion properties are extracted at different frequency ranges. Conventional noise suppression techniques in passive data are mostly stacking-based that rely on enforcing the amplitude of the signal by stacking the waveforms at the receivers and are unable to preserve the waveforms at the individual receivers necessary for estimating the microseismic source location and source mechanism. Here, I introduce a technique based on the tau - p transform, that effectively identifies and separates microseismic events from surface-wave noise in the tau -p domain. This technique is superior to conventional stacking-based noise suppression techniques, because it preserves the waveforms at individual receivers. Application of this methodology to microseismic events with isotropic and double-couple source mechanism

  9. A Counterregulatory Mechanism Impacting Androgen Suppression Therapy

    Science.gov (United States)

    2016-03-01

    improving public knowledge, attitudes , skills, and abilities; • changing behavior, practices, decision making, policies (including regulatory policies), or...colytic capacity of tumor cells in the presence of oxygen (69). Consequently, caution must be exercised in extrap- olating metabolic findings in...increased proliferation or enlargement in response to hypocalce- mia induced by a low calcium/vitamin D diet . These studies iden- tified Gcm2, a gene

  10. Influence of Particle Size in Talc Suppression by a Galactomannan Depressant

    Directory of Open Access Journals (Sweden)

    Zhixiang Chen

    2018-03-01

    Full Text Available Flotation behavior of different sizes of particles may follow different trends. The influence of particle size in talc suppression by a depressant galactomannan was studied in this research. The flotation response and mechanism were examined by flotation tests, modified flotation rate constant and entrainment recovery calculation, laser particle size experiments, adsorption tests, and advancing contact angle measurement as well as scanning electron microscopy (SEM and energy dispersive X-ray spectrometry (EDS. The maximum recovery increased with particle size increases in the absence of galactomannan FPY (Fenugreek polysaccharide. The obviously suppressed effect was observed for the size fraction of −74 + 38 μm after reacting with FPY, but low efficiency was received for −38 μm and −10 μm, respectively. Laser particle size analysis indicated that the FPY has a certain function for the flocculation of fine particles. It is beneficial for reducing recovery by entrainment. EDS and advancing contact angle test results showed that the difference in contact angles probably is a result of genuine differences in the quantity of O and Mg bearing surface species, while the contact angle varied with particle size fraction in the absence of FPY. Adsorption and SEM test results demonstrated that in the case of −74 + 38 μm, the depressant adsorption density on the mineral surface is higher than the other two size fractions. On the whole, FPY probably is not enough of a depressant for talc suppression.

  11. Suppression of the Polar Tongue of Ionization During the 21 August 2017 Solar Eclipse

    Science.gov (United States)

    Dang, Tong; Lei, Jiuhou; Wang, Wenbin; Burns, Alan; Zhang, Binzheng; Zhang, Shun-Rong

    2018-04-01

    It has long been recognized that during solar eclipses, the ionosphere-thermosphere system changes greatly within the eclipse shadow, due to the rapid reduction of solar irradiation. However, the concept that a solar eclipse impacts polar ionosphere behavior and dynamics as well as magnetosphere-ionosphere coupling has not been appreciated. In this study, we investigate the potential impact of the 21 August 2017 solar eclipse on the polar tongue of ionization (TOI) using a high-resolution, coupled ionosphere-thermosphere-electrodynamics model. The reduction of electron densities by the eclipse in the middle latitude TOI source region leads to a suppressed TOI in the polar region. The TOI suppression occurred when the solar eclipse moved into the afternoon sector. The Global Positioning System total electron content observations show similar tendency of polar region total electron content suppression. This study reveals that a solar eclipse occurring at middle latitudes may have significant influences on the polar ionosphere and magnetosphere-ionosphere coupling.

  12. Bandwidth-limited control and ringdown suppression in high-Q resonators.

    Science.gov (United States)

    Borneman, Troy W; Cory, David G

    2012-12-01

    We describe how the transient behavior of a tuned and matched resonator circuit and a ringdown suppression pulse may be integrated into an optimal control theory (OCT) pulse-design algorithm to derive control sequences with limited ringdown that perform a desired quantum operation in the presence of resonator distortions of the ideal waveform. Inclusion of ringdown suppression in numerical pulse optimizations significantly reduces spectrometer deadtime when using high quality factor (high-Q) resonators, leading to increased signal-to-noise ratio (SNR) and sensitivity of inductive measurements. To demonstrate the method, we experimentally measure the free-induction decay of an inhomogeneously broadened solid-state free radical spin system at high Q. The measurement is enabled by using a numerically optimized bandwidth-limited OCT pulse, including ringdown suppression, robust to variations in static and microwave field strengths. We also discuss the applications of pulse design in high-Q resonators to universal control of anisotropic-hyperfine coupled electron-nuclear spin systems via electron-only modulation even when the bandwidth of the resonator is significantly smaller than the hyperfine coupling strength. These results demonstrate how limitations imposed by linear response theory may be vastly exceeded when using a sufficiently accurate system model to optimize pulses of high complexity. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Flutter suppression and stability analysis for a variable-span wing via morphing technology

    Science.gov (United States)

    Li, Wencheng; Jin, Dongping

    2018-01-01

    A morphing wing can enhance aerodynamic characteristics and control authority as an alternative to using ailerons. To use morphing technology for flutter suppression, the dynamical behavior and stability of a variable-span wing subjected to the supersonic aerodynamic loads are investigated numerically in this paper. An axially moving cantilever plate is employed to model the variable-span wing, in which the governing equations of motion are established via the Kane method and piston theory. A morphing strategy based on axially moving rates is proposed to suppress the flutter that occurs beyond the critical span length, and the flutter stability is verified by Floquet theory. Furthermore, the transient stability during the morphing motion is analyzed and the upper bound of the morphing rate is obtained. The simulation results indicate that the proposed morphing law, which is varying periodically with a proper amplitude, could accomplish the flutter suppression. Further, the upper bound of the morphing speed decreases rapidly once the span length is close to its critical span length.

  14. Task-irrelevant memory load induces inattentional blindness without temporo-parietal suppression.

    Science.gov (United States)

    Matsuyoshi, Daisuke; Ikeda, Takashi; Sawamoto, Nobukatsu; Kakigi, Ryusuke; Fukuyama, Hidenao; Osaka, Naoyuki

    2010-08-01

    We often fail to consciously detect an unexpected object when we are engaged in an attention-demanding task (inattentional blindness). The inattentional blindness which is induced by visual short-term memory (VSTM) load has been proposed to result from a suppression of temporo-parietal junction (TPJ) activity that involves stimulus-driven attention. However, the fact that, inversely proportional to TPJ activity, intraparietal sulcus (IPS) activity correlates with VSTM load renders questionable the account of inattentional blindness based only on TPJ activity. Here, we investigated whether the TPJ is solely responsible for inattentional blindness by decoupling IPS and TPJ responses to VSTM load and then using the same manipulation to test the behavioral inattentional blindness performance. Experiment 1 showed that TPJ activity was not suppressed by task-irrelevant load while the IPS responded to both task-relevant and task-irrelevant load. Although the TPJ account of inattentional blindness predicts that the degree of inattentional blindness should track TPJ activity, we found in Experiment 2 that inattentional blindness was induced not only by task-relevant load but also by task-irrelevant load, showing inconsistency between the extent of inattentional blindness and TPJ response. These findings suggest that inattentional blindness can be induced without suppression of TPJ activity and seem to offer the possibility that the IPS contributes to conscious perception. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  15. The person within: memory codes for persons and traits using fMRI repetition suppression.

    Science.gov (United States)

    Heleven, Elien; Van Overwalle, Frank

    2016-01-01

    Neuroimaging studies on trait inference demonstrated that the ventral medial prefrontal cortex (mPFC) houses neural representations of memory codes for traits . In this study, we investigate the neural code not only of traits, but also of persons who exemplify these traits. We used repetition suppression, which is a rapid suppression of the neuroimaging signal upon repeated presentation of the same stimulus or core stimulus characteristics-in this case, the implied trait and person. Participants inferred familiar person's traits. At each trial, a critical (target) sentence described a behavior that implied a trait, and was preceded by a (prime) sentence that implied the same trait and portrayed the same person, the same trait but portrayed a different person or did not imply a trait and portrayed a different person. As predicted, we found partly overlapping repetition suppression areas in the ventral mPFC when persons and traits were repeated, indicating that not only traits but also familiar persons have a neural code in the ventral mPFC. We also found a negative correlation between activation when reading about a new person and participants' social network size, indicating that experience with larger social groups results in less recruitment of a person code. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  16. Using Correlated Photons to Suppress Background Noise

    Science.gov (United States)

    Jackson, Deborah; Hockney, George; Dowling, Jonathan

    2003-01-01

    A proposed method of suppressing the effect of background noise in an optical communication system would exploit the transmission and reception of correlated photons at the receiver. The method would not afford any advantage in a system in which performance is limited by shot noise. However, if the performance of the system is limited by background noise (e.g., sunlight in the case of a free-space optical communication system or incoherently scattered in-band photons in the case of a fiber-optic communication system), then the proposed method could offer an advantage: the proposed method would make it possible to achieve a signal-to-noise ratio (S/N) significantly greater than that of an otherwise equivalent background- noise-limited optical communication system based on the classical transmission and reception of uncorrelated photons. The figure schematically depicts a classical optical-communication system and a system according to the proposed method. In the classical system, a modulated laser beam is transmitted along an optical path to a receiver, the optics of which include a narrow-band-pass filter that suppresses some of the background noise. A photodetector in the receiver detects the laser-beam and background photons, most or all of which are uncorrelated. In the proposed system, correlated photons would be generated at the transmitter by making a modulated laser beam pass through a nonlinear parametric down-conversion crystal. The sum of frequencies of the correlated photons in each pair would equal the frequency of the incident photon from which they were generated. As in the classical system, the correlated photons would travel along an optical path to a receiver, where they would be band-pass filtered and detected. Unlike in the classical system, the photodetector in the receiver in this system would be one that intrinsically favors the detection of pairs of correlated photons over the detection of uncorrelated photons. Even though there would be no

  17. Suitable level of suppression in Pinus sylvestris

    Energy Technology Data Exchange (ETDEWEB)

    Hagner, Mats

    1999-10-01

    It is `well known` among Swedish foresters that pine trees need light and cannot grow suppressed. It is also `well known` that old trees that have grown slowly are unable to react with good growth. However, these facts can be questioned in the light of new research as it has been found that thinning reaction is not correlated with age. It is also well known that the commercial value of a pine is closely related to the growth at young age. If the first 20 annual rings close to pith are wide (>3 mm) the log cannot be accepted as first class. This is related to number and size of branches on the young tree and to the features of the juvenile wood. This is to say that a pine must not grow fast when it is small and if this has happened it cannot be cured by artificial debranching or by growing the tree slowly at higher age. Accordingly, young pines should be grown under bigger trees that in their young age were grown under big trees, and so on. Today, when clear cutting is the dominating forest management system, the only way to obtain high quality pine trees is to start the rotation age with stands of very high density. This is of course a very expensive way as dense planting, followed by intensive thinning requires a lot of input. However, if pine is a pioneer species and cannot be grown in multistoried stands, then the economic solution is not present. This was the reason why the annual increment of three pines was measured. They were selected because their different growth pattern showed that old `well known facts` should be revised Working papers 139. 3 refs, 7 figs, 1 tab

  18. Pocket Proteins Suppress Head and Neck Cancer

    Science.gov (United States)

    Shin, Myeong-Kyun; Pitot, Henry C.; Lambert, Paul F.

    2012-01-01

    Head and neck squamous cell carcinomas (HNSCC) is a common cancer in humans long known to be caused by tobacco and alcohol use, but now an increasing percentage of HNSCC is recognized to be caused by the same human papillomaviruses (HPVs) that cause cervical and other anogenital cancers. HPV-positive HNSCCs differ remarkably from HPV-negative HNSCCs in their clinical response and molecular properties. From studies in mice, we know that E7 is the dominant HPV oncoprotein in head and neck cancer. E7 is best known for its ability to inactivate pRb, the product of the retinoblastoma tumor susceptibility gene. However loss of pRb function does not fully account for E7’s potency in causing head and neck cancer. In this study, we characterized the cancer susceptibility of mice deficient in the expression of pRb and either of two related “pocket” proteins, p107 and p130, that are also inactivated by E7. pRb/p107 deficient mice developed head and neck cancer as frequently as do HPV16 E7 transgenic mice. The head and neck epithelia of the pRb/p107 deficient mice also displayed the same acute phenotypes and biomarker readouts as observed in the epithelia of E7 transgenic mice. Mice deficient for pRb and p130 in their head and neck epithelia showed intermediate acute and tumor phenotypes. We conclude that pRb and p107 act together to efficiently suppress head and neck cancer, and are therefore highly relevant targets of HPV16 E7 in its contribution to HPV-positive HNSCC. PMID:22237625

  19. Suppression of in vitro cell-mediated lympholysis generation by alloactivated lymphocytes. Examination of radioresistant suppressive activity

    International Nuclear Information System (INIS)

    Orosz, C.G.; Ferguson, R.M.

    1986-01-01

    We investigated the radioresistant (1000 rads) suppression of CML generation mediated by alloactivated murine splenocytes. Suppressive cells were generated in MLCs by stimulation of (A X 6R)F1 splenocytes with irradiated C57BL/10 splenocytes. Suppressive cells could lyse targets bearing H-2b alloantigens, but would not lyse parental B10.T(6R) or B10.A targets. Suppressive activity was detected by including the alloactivated (A X 6R)F1 cells in B10.T(6R) anti-B10.A(1R) MLCs. Relative to the suppressive (A X 6R)F1 cells, the B10.A(1R) lymphocytes display both parental and suppressor-inducing alloantigens. In the absence of a suppressive population, B10.A(1R) stimulators cause B10.T(6R) splenocytes to generate cytolytic activity specific for both H-2Db (suppressor-inducing) and H-2Kk (suppressor-borne) target determinants. The irradiated, alloactivated (A X 6R)F1 cells decrease the H-2Db-specific CML generated in this system, thus mediating apparent antigen-specific suppression. However, cytolytic activity concomitantly generated in the same culture against the unrelated H-2Kk target determinants is similarly reduced by the (A X 6R)F1 cells. Thus, radioresistant suppression by alloactivated splenocytes is not necessarily antigen-specific. The irradiated (A X 6R)F1 cells would not suppress the generation of H-2Kk-specific CTL in B10.T(6R) anti-B10.A MLCs. Hence, the irradiated (A X 6R)F1 cells can impede CML generation against third-party alloantigens if, and only if, those alloantigens are coexpressed with suppressor-inducing alloantigens on the stimulator cells in suppressed MLCs. Similar results were also obtained using a different histoincompatible lymphocyte combination

  20. Behavioral finance

    Directory of Open Access Journals (Sweden)

    Kapor Predrag

    2014-01-01

    Full Text Available This paper discuss some general principles of behavioral finance Behavioral finance is the dynamic and promising field of research that mergers concepts from financial economics and cognitive psychology in attempt to better understand systematic biases in decision-making process of financial agents. While the standard academic finance emphasizes theories such as modern portfolio theory and the efficient market hypothesis, the behavioral finance investigates the psychological and sociological issues that impact the decision-making process of individuals, groups and organizations. Most of the research behind behavioral finance has been empirical in nature, concentrating on what people do and why. The research has shown that people do not always act rationally, nor they fully utilise all information available to them.

  1. Behavior change

    Science.gov (United States)

    This brief entry presents the mediating-moderating variable model as a conceptual framework for understanding behavior change in regard to physical activity/exercise and adiposity. The ideas are applied to real world situations....

  2. When passion makes the heart grow colder: the role of passion in alternative goal suppression.

    Science.gov (United States)

    Bélanger, Jocelyn J; Lafrenière, Marc-André K; Vallerand, Robert J; Kruglanski, Arie W

    2013-01-01

    Quality of goal engagement and alternative goal suppression were investigated in this research. Integrating the dualistic model of passion (Vallerand et al., 2003) with goal-systems theory (Kruglanski et al., 2002), we hypothesized that obsessive passion--associated with recurrent goal-conflicts--would predict greater alternative goal suppression (i.e., goal-shielding) than would harmonious passion--characterized by effective synthesis of the passionate activity with other life domains. Results from 5 laboratory studies supported these hypotheses. In Study 1, participants' dispositional measures of harmonious and obsessive passion were correlated with an implicit measure of goal-shielding. Obsessive (but not harmonious) passion predicted the suppression of alternative goals and the progressive inhibition of unfamiliar goals. In Study 2, we extended these findings by demonstrating the interrelation between quality of goal engagement and goal-commitment such that goal-shielding effects were enhanced, but only for goals in conflict with other life domains (vs. well-integrated goals). In Study 3, the causal influence of passion on goal-shielding was supported via an experimental manipulation of passion. In Study 4, we replicated and extended Studies 1 and 3 by experimentally demonstrating that obsessive (but not harmonious) passion is a mindset conducive to the development of inhibitory links with alternative goals. Study 5 explored the psychological costs associated with repeated unconscious goal suppression by examining its effects on the depletion of self-regulatory resources. Collectively, the present results suggest that the qualitative distinction between obsessive and harmonious passion has implications for the goal-shielding effect and for subsequent self-regulatory behavior.

  3. Cross-cultural differences in emotion suppression in everyday interactions.

    Science.gov (United States)

    Huwaë, Sylvia; Schaafsma, Juliette

    2016-05-11

    Previous research suggests that in collectivistic cultures, people tend to suppress their emotions more than in individualistic cultures. Little research, however, has explored cross-cultural differences in emotion regulation in everyday interactions. Using a daily social interaction method, we examined whether people from collectivistic backgrounds (Chinese exchange students and immigrants from the Moluccas, Indonesia) living in the Netherlands differed from those from individualistic backgrounds (Dutch natives) in emotion suppression during everyday interactions. We also examined whether this depended on their relationship with the interaction partner(s). We found that Chinese participants suppressed positive and negative emotions more than Dutch and Moluccan participants and that this was related to differences in interdependent and independent self-construal across the samples. We also found that Chinese participants suppressed positive emotions less in interactions with close others, whereas Dutch participants suppressed negative emotions more with non-close others. No such differences were found for Moluccans. Our findings support the idea that people from collectivistic cultures suppress emotions more than those from individualistic cultures, but they also suggest that this depends on who the interaction partner is. Furthermore, they suggest that emotion suppression may change when people with collectivistic backgrounds have been raised in individualistic cultures. © 2016 International Union of Psychological Science.

  4. Quantum suppression of superconductivity in nanowires

    International Nuclear Information System (INIS)

    Bezryadin, Alexey

    2008-01-01

    It is of fundamental importance to establish whether there is a limit to how thin a superconducting wire can be, while retaining its superconducting character-and if there is such limit, to understand what determines it. This issue may be of practical importance in defining the limit to miniaturization of superconducting electronic circuits. Recently, a new fabrication method, called molecular templating, was developed and used to answer such questions. In this approach, a suspended carbon nanotube is coated with a thin superconducting metal film, thus forming a superconducting nanowire. The wire obtained is automatically attached to the two leads formed by the sides of the trench. The usual material for such wires is the amorphous alloy of MoGe (Graybeal 1985 PhD Thesis Stanford University; Graybeal and Beasley 1984 Phys. Rev. B 29 4167; Yazdani and Kapitulnik 1995 Phys. Rev. Lett. 74 3037; Turneaure et al 2000 Phys. Rev. Lett. 84 987). Such wires typically exhibit a high degree of homogeneity and can be made very small: as thin as ∼5 nm in diameter and as short as ∼40 nm in length. The results of transport measurements on such homogeneous wires can be summarized as follows. Short wires, shorter than some empirical length, ∼200 nm for MoGe, exhibit a clear dichotomy. They show either a superconducting behavior, with the resistance controlled by thermal fluctuations, or a weakly insulating behavior, with the resistance controlled by the weak Coulomb blockade. Thus a quantum superconductor-insulator transition (SIT) is indicated. Longer wires exhibit a gradual crossover behavior, from almost perfectly superconducting to normal or weakly insulating behavior, as their diameter is reduced. Measurements of wires, which are made inhomogeneous (granular) on purpose, show that such wires, even if they are short in the sense stated above, do not show a clear dichotomy, which could be identified as an SIT (Bollinger et al 2004 Phys. Rev. B 69 180503(R)). Thus

  5. Investigation of the suppression effect of polyethylene glycol on copper electroplating by electrochemical impedance spectroscopy

    International Nuclear Information System (INIS)

    Hung, C.-C.; Lee, W.-H.; Wang, Y.-L.; Chan, D.-Y.; Hwang, G.-J.

    2008-01-01

    Polyethylene glycol (PEG) is an additive that is commonly used as a suppressor in the semiconductor copper (Cu)-electroplating process. In this study, electrochemical impedance spectroscopy (EIS) was used to analyze the electrochemical behavior of PEG in the Cu-electroplating process. Polarization analysis, cyclic-voltammetry stripping, and cell voltage versus plating time were examined to clarify the suppression behavior of PEG. The equivalent circuit simulated from the EIS data shows that PEG inhibited the Cu-electroplating rate by increasing the charge-transfer resistance as well as the resistance of the adsorption layer. The presence of a large inductance demonstrated the strong adsorption of cuprous-PEG-chloride complexes on the Cu surface during the Cu-electroplating process. Increasing the PEG concentration appears to increase the resistances of charge transfer, the adsorption layer, and the inductance of the electroplating system

  6. Comparative Metatranscriptomics of Wheat Rhizosphere Microbiomes in Disease Suppressive and Non-suppressive Soils for Rhizoctonia solani AG8

    Directory of Open Access Journals (Sweden)

    Helen L. Hayden

    2018-05-01

    Full Text Available The soilborne fungus Rhizoctonia solani anastomosis group (AG 8 is a major pathogen of grain crops resulting in substantial production losses. In the absence of resistant cultivars of wheat or barley, a sustainable and enduring method for disease control may lie in the enhancement of biological disease suppression. Evidence of effective biological control of R. solani AG8 through disease suppression has been well documented at our study site in Avon, South Australia. A comparative metatranscriptomic approach was applied to assess the taxonomic and functional characteristics of the rhizosphere microbiome of wheat plants grown in adjacent fields which are suppressive and non-suppressive to the plant pathogen R. solani AG8. Analysis of 12 rhizosphere metatranscriptomes (six per field was undertaken using two bioinformatic approaches involving unassembled and assembled reads. Differential expression analysis showed the dominant taxa in the rhizosphere based on mRNA annotation were Arthrobacter spp. and Pseudomonas spp. for non-suppressive samples and Stenotrophomonas spp. and Buttiauxella spp. for the suppressive samples. The assembled metatranscriptome analysis identified more differentially expressed genes than the unassembled analysis in the comparison of suppressive and non-suppressive samples. Suppressive samples showed greater expression of a polyketide cyclase, a terpenoid biosynthesis backbone gene (dxs and many cold shock proteins (csp. Non-suppressive samples were characterised by greater expression of antibiotic genes such as non-heme chloroperoxidase (cpo which is involved in pyrrolnitrin synthesis, and phenazine biosynthesis family protein F (phzF and its transcriptional activator protein (phzR. A large number of genes involved in detoxifying reactive oxygen species (ROS and superoxide radicals (sod, cat, ahp, bcp, gpx1, trx were also expressed in the non-suppressive rhizosphere samples most likely in response to the infection of wheat

  7. Suppression of ion conductance by electro-osmotic flow in nano-channels with weakly overlapping electrical double layers

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2016-08-01

    Full Text Available This theoretical study investigates the nonlinear ionic current-voltage characteristics of nano-channels that have weakly overlapping electrical double layers. Numerical simulations as well as a 1-D mathematical model are developed to reveal that the electro-osmotic flow (EOF interplays with the concentration-polarization process and depletes the ion concentration inside the channels, thus significantly suppressing the channel conductance. The conductance may be restored at high electrical biases in the presence of recirculating vortices within the channels. As a result of the EOF-driven ion depletion, a limiting-conductance behavior is identified, which is intrinsically different from the classical limiting-current behavior.

  8. Suppressing voltage transients in high voltage power supplies

    International Nuclear Information System (INIS)

    Lickel, K.F.; Stonebank, R.

    1979-01-01

    A high voltage power supply for an X-ray tubes includes voltage adjusting means, a high voltage transformer, switch means connected to make and interrupt the primary current of the transformer, and over-voltage suppression means to suppress the voltage transient produced when the current is switched on. In order to reduce the power losses in the suppression means, an impedance is connected in the transformer primary circuit on operation of the switch means and is subsequently short-circuited by a switch controlled by a timer after a period which is automatically adjusted to the duration of the transient overvoltage. (U.K.)

  9. Suppression of persistent photo-conductance in solution-processed amorphous oxide thin-film transistors

    Science.gov (United States)

    Lee, Minkyung; Kim, Minho; Jo, Jeong-Wan; Park, Sung Kyu; Kim, Yong-Hoon

    2018-01-01

    This study offers a combinatorial approach for suppressing the persistent photo-conductance (PPC) characteristic in solution-processed amorphous oxide semiconductor (AOS) thin-film transistors (TFTs) in order to achieve rapid photo-recovery. Various analyses were used to examine the photo-instability of indium-gallium-zinc-oxide (IGZO) TFTs including negative-bias-illumination-stress (NBIS) and transient photo-response behaviors. It was found that the indium ratio in metallic components had a significant impact on their PPC and photo-recovery characteristics. In particular, when the indium ratio was low (51.5%), the PPC characteristic was significantly suppressed and achieving rapid photo-recovery was possible without significantly affecting the electrical performance of AOSs. These results imply that the optimization of the indium composition ratio may allow achieving highly photo-stable and near PPC-free characteristics while maintaining high electrical performance of AOSs. It is considered that the negligible PPC behavior and rapid photo-recovery observed in IGZO TFTs with a lower indium composition are attributed to the less activation energy required for the neutralization of ionized oxygen vacancies.

  10. Social exclusion impairs distractor suppression but not target enhancement in selective attention.

    Science.gov (United States)

    Xu, Mengsi; Li, Zhiai; Diao, Liuting; Fan, Lingxia; Zhang, Lijie; Yuan, Shuge; Yang, Dong

    2017-11-01

    Social exclusion has been thought to weaken one's ability to exert inhibitory control. Existing studies have primarily focused on the relationship between exclusion and behavioral inhibition, and have reported that exclusion impairs behavioral inhibition. However, whether exclusion also affects selective attention, another important aspect of inhibitory control, remains unknown. Therefore, the current study aimed to explore whether social exclusion impairs selective attention, and to specifically examine its effect on two hypothesized mechanisms of selective attention: target enhancement and distractor suppression. The Cyberball game was used to manipulate social exclusion. Participants then performed a visual search task while event-related potentials were recorded. In the visual search task, target and salient distractor were either both presented laterally or one was presented on the vertical midline and the other laterally. Results showed that social exclusion differentially affected target and distractor processing. While exclusion impaired distractor suppression, reflected as smaller distractor-positivity (Pd) amplitudes for the exclusion group compared to the inclusion group, it did not affect target enhancement, reflected as similar target-negativity (Nt) amplitudes for both the exclusion and inclusion groups. Together, these results extend our understanding of the relationship between exclusion and inhibitory control, and suggest that social exclusion affects selective attention in a more complex manner than previously thought. Copyright © 2017. Published by Elsevier B.V.

  11. Cloud Processed CCN Suppress Stratus Cloud Drizzle

    Science.gov (United States)

    Hudson, J. G.; Noble, S. R., Jr.

    2017-12-01

    Conversion of sulfur dioxide to sulfate within cloud droplets increases the sizes and decreases the critical supersaturation, Sc, of cloud residual particles that had nucleated the droplets. Since other particles remain at the same sizes and Sc a size and Sc gap is often observed. Hudson et al. (2015) showed higher cloud droplet concentrations (Nc) in stratus clouds associated with bimodal high-resolution CCN spectra from the DRI CCN spectrometer compared to clouds associated with unimodal CCN spectra (not cloud processed). Here we show that CCN spectral shape (bimodal or unimodal) affects all aspects of stratus cloud microphysics and drizzle. Panel A shows mean differential cloud droplet spectra that have been divided according to traditional slopes, k, of the 131 measured CCN spectra in the Marine Stratus/Stratocumulus Experiment (MASE) off the Central California coast. K is generally high within the supersaturation, S, range of stratus clouds (< 0.5%). Because cloud processing decreases Sc of some particles, it reduces k. Panel A shows higher concentrations of small cloud droplets apparently grown on lower k CCN than clouds grown on higher k CCN. At small droplet sizes the concentrations follow the k order of the legend, black, red, green, blue (lowest to highest k). Above 13 µm diameter the lines cross and the hierarchy reverses so that blue (highest k) has the highest concentrations followed by green, red and black (lowest k). This reversed hierarchy continues into the drizzle size range (panel B) where the most drizzle drops, Nd, are in clouds grown on the least cloud-processed CCN (blue), while clouds grown on the most processed CCN (black) have the lowest Nd. Suppression of stratus cloud drizzle by cloud processing is an additional 2nd indirect aerosol effect (IAE) that along with the enhancement of 1st IAE by higher Nc (panel A) are above and beyond original IAE. However, further similar analysis is needed in other cloud regimes to determine if MASE was

  12. Suppression of the dayside magnetopause surface modes

    Directory of Open Access Journals (Sweden)

    Pilipenko V.A.

    2017-12-01

    Full Text Available Magnetopause surface eigenmodes were suggested as a potential source of dayside high-latitude broadband pulsations in the Pc5-6 band (frequency about 1–2 mHz. However, the search for a ground signature of these modes has not provided encouraging results. The comparison of multi-instrument data from Svalbard with the latitudinal structure of Pc5-6 pulsations, recorded by magnetometers covering near-cusp latitudes, has shown that often the latitudinal maximum of pulsation power occurs about 2–3° deeper in the magnetosphere than the dayside open-closed field line boundary (OCB. The OCB proxy was determined from SuperDARN radar data as the equatorward boundary of enhanced width of a return radio signal. The OCB-ULF correspondence is further examined by comparing the latitudinal profile of the near-noon pulsation power with the equatorward edge of the auroral red emission from the meridian scanning photometer. In most analyzed events, the “epicenter” of Pc5-6 power is at 1–2° lower latitude than the optical OCB proxy. Therefore, the dayside Pc5-6 pulsations cannot be associated with the ground image of the magnetopause surface modes or with oscillations of the last field line. A lack of ground response to these modes beneath the ionospheric projection of OCB seems puzzling. As a possible explanation, we suggest that a high variability of the outer magnetosphere near the magnetopause region may suppress the excitation efficiency. To quantify this hypothesis, we consider a driven field line resonator terminated by conjugate ionospheres with stochastic fluctuations of its eigenfrequency. A solution of this problem predicts a substantial deterioration of resonant properties of MHD resonator even under a relatively low level of background fluctuations. This effect may explain why there is no ground response to magnetopause surface modes or oscillations of the last field line at the OCB latitude, but it can be seen at somewhat lower latitudes

  13. Suppressive effects of a polymer sodium silicate solution on ...

    African Journals Online (AJOL)

    Mohsen

    2015-10-21

    Oct 21, 2015 ... suppressive effects of sodium silicate in the polymer form were confirmed against powdery mildew and ... crops (such as rice) controls diseases and could reduce ... negative charge and sodium ions with a positive charge.

  14. Nonlinear Suppression of Range Ambiguity in Pulse Doppler Radar

    National Research Council Canada - National Science Library

    Anderson, Jon

    2001-01-01

    ... ambiguities in Doppler and range. First introduced by Palermo in 1962 using two conjugate LFM pulses, the primary nonlinear suppression objective involves reducing range ambiguity, given the waveform is nominally unambiguous...

  15. Suppression of magnetic islands by rf-driven currents

    International Nuclear Information System (INIS)

    Reiman, A.H.

    1982-06-01

    The quasilinear theory for the saturation of nonlinear tearing modes is modified to include rf driven currents. It is shown that the presence of lower hybrid driven currents can strongly suppress the growth of magnetic islands

  16. New fat suppression RF pulse with shorter duration

    International Nuclear Information System (INIS)

    Yamaguchi, Kojiro; Ukai, Hiroyuki

    2010-01-01

    The fat suppression radio frequency pulse currently employed for MRI, which selectively saturates the frequency of the fat, has the narrow-band frequency characteristics. Therefore, the application duration for the pulse employed tends to be prolonged. In the present study, we designed a new fat suppression radiofrequency (RF) pulse using the Laguerre function in order to shorten the duration for fat suppression RF pulse and conducted an evaluation with the clinical equipment. The length of the RF pulse that we created allowed to reduce the duration by 47.3% compared with that employed for the clinical equipment. In addition, in the MR imaging evaluation, the new pulse was confirmed to have the fat suppression effect equivalent to that employed for the clinical equipment. (author)

  17. Suppression of multiphoton excitation in resonance ionization measurements

    International Nuclear Information System (INIS)

    Garrett, W.R.; Moore, M.A.; Wunderlich, R.K.; Payne, M.G.

    1988-04-01

    We describe experimental confirmation of strong suppressions of laser-driven nonlinear absorption processes by electromagnetic fields through other nonlinear processes within a given atomic or molecular medium. (AR)

  18. Cross-cultural differences in emotion suppression in everyday interactions

    NARCIS (Netherlands)

    Huwae, Sylvia; Schaafsma, Juliëtte

    Previous research suggests that in collectivistic cultures, people tend to suppress their emotions more than in individualistic cultures. Little research, however, has explored cross-cultural differences in emotion regulation in everyday interactions. Using a daily social interaction method, we

  19. Acetonitrile Ion Suppression in Atmospheric Pressure Ionization Mass Spectrometry

    Science.gov (United States)

    Colizza, Kevin; Mahoney, Keira E.; Yevdokimov, Alexander V.; Smith, James L.; Oxley, Jimmie C.

    2016-11-01

    Efforts to analyze trace levels of cyclic peroxides by liquid chromatography/mass spectrometry gave evidence that acetonitrile suppressed ion formation. Further investigations extended this discovery to ketones, linear peroxides, esters, and possibly many other types of compounds, including triazole and menadione. Direct ionization suppression caused by acetonitrile was observed for multiple adduct types in both electrospray ionization and atmospheric pressure chemical ionization. The addition of only 2% acetonitrile significantly decreased the sensitivity of analyte response. Efforts to identify the mechanism were made using various nitriles. The ion suppression was reduced by substitution of an acetonitrile hydrogen with an electron-withdrawing group, but was exacerbated by electron-donating or steric groups adjacent to the nitrile. Although current theory does not explain this phenomenon, we propose that polar interactions between the various functionalities and the nitrile may be forming neutral aggregates that manifest as ionization suppression.

  20. Central nervous system stimulants and drugs that suppress appetite

    DEFF Research Database (Denmark)

    Aagaard, Lise

    2014-01-01

    of the January 2012 to June 2013 publications on central nervous system stimulants and drugs that suppress appetite covers amphetamines (including metamfetamine, paramethoxyamfetamine and paramethoxymetamfetamine), fenfluramine and benfluorex, atomoxetine, methylphenidate, modafinil and armodafinil...

  1. Suppression of vortex shedding around a square cylinder using ...

    Indian Academy of Sciences (India)

    control of vortex shedding of square cylinders using blowing or suction. ... also showed complete suppression of vortex shedding if suction velocity falls between 0.40 .... equations such that mass balance (continuity) is satisfied simultaneously.

  2. Charmonium suppression in a quark exchange model

    International Nuclear Information System (INIS)

    Martins, K.

    1995-01-01

    A diagrammatic approach to quark exchange processes in meson-meson scattering is applied to the case of inelastic reactions of the type (Q anti Q)+(q anti q)→(Q anti q)+(q anti Q), where Q and q refer to heavy and light quarks, respectively. This string-flip process is discussed as a microscopic mechanism for charmonium dissociation (absorption) in hadronic matter. The cross section for the reaction J/ψ+π→D+ anti D is calculated using a potential model. The behavior of a formed charmonium state in hadronic matter are discussed and consequences for ultrarelativistic hadron-nucleus and nucleus-nucleus collisions are discussed. (orig.)

  3. Adaptive transmit selection with interference suppression

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2010-01-01

    This paper studies the performance of adaptive transmit channel selection in multipath fading channels. The adaptive selection algorithms are configured for single-antenna bandwidth-efficient or power-efficient transmission with as low transmit channel estimations as possible. Due to the fact that the number of active co-channel interfering signals and their corresponding powers experience random behavior, the adaptation to channels conditions, assuming uniform buffer and traffic loading, is proposed to be jointly based on the transmit channels instantaneous signal-to-noise ratios (SNRs) and signal-to- interference-plus- noise ratios (SINRs). Two interference cancelation algorithms, which are the dominant cancelation and the less complex arbitrary cancelation, are considered, for which the receive antenna array is assumed to have small angular spread. Analytical formulation for some performance measures in addition to several processing complexity and numerical comparisons between various adaptation schemes are presented. ©2010 IEEE.

  4. Behavioral addictions.

    Science.gov (United States)

    Robbins, T W; Clark, L

    2015-02-01

    Behavioral addictions are slowly becoming recognized as a valid category of psychiatric disorder as shown by the recent allocation of pathological gambling to this category in DSM-5. However, several other types of psychiatric disorder proposed to be examples of behavioral addictions have yet to be accorded this formal acknowledgment and are dispersed across other sections of the DSM-5. This brief review marks this important point in the evolution of this concept and looks to future investigation of behavioral addictions with the theoretical frameworks currently being used successfully to investigate substance addiction and obsessive-compulsive disorder, in a potentially new spectrum of impulsive-compulsive disorders. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Cost Behavior

    DEFF Research Database (Denmark)

    Hoffmann, Kira

    The objective of this dissertation is to investigate determinants and consequences of asymmetric cost behavior. Asymmetric cost behavior arises if the change in costs is different for increases in activity compared to equivalent decreases in activity. In this case, costs are termed “sticky......” if the change is less when activity falls than when activity rises, whereas costs are termed “anti-sticky” if the change is more when activity falls than when activity rises. Understanding such cost behavior is especially relevant for decision-makers and financial analysts that rely on accurate cost information...... to facilitate resource planning and earnings forecasting. As such, this dissertation relates to the topic of firm profitability and the interpretation of cost variability. The dissertation consists of three parts that are written in the form of separate academic papers. The following section briefly summarizes...

  6. Neural Correlates of Direct and Indirect Suppression of Autobiographical Memories.

    Science.gov (United States)

    Noreen, Saima; O'Connor, Akira R; MacLeod, Malcolm D

    2016-01-01

    Research indicates that there are two possible mechanisms by which particular target memories can be intentionally forgotten. Direct suppression, which involves the suppression of the unwanted memory directly, and is dependent on a fronto-hippocampal modulatory process, and, memory substitution, which includes directing one's attention to an alternative memory in order to prevent the unwanted memory from coming to mind, and involves engaging the caudal prefrontal cortex (cPFC) and the mid-ventrolateral prefrontal cortex (VLPFC) regions. Research to date, however, has investigated the neural basis of memory suppression of relatively simple information. The aim of the current study was to use fMRI to identify the neural mechanisms associated with the suppression of autobiographical memories. In the present study, 22 participants generated memories in response to a series of cue words. In a second session, participants learnt these cue-memory pairings, and were subsequently presented with a cue word and asked either to recall (think) or to suppress (no-think) the associated memory, or to think of an alternative memory in order to suppress the original memory (memory-substitution). Our findings demonstrated successful forgetting effects in the no-think and memory substitution conditions. Although we found no activation in the dorsolateral prefrontal cortex, there was reduced hippocampal activation during direct suppression. In the memory substitution condition, however, we failed to find increased activation in the cPFC and VLPFC regions. Our findings suggest that the suppression of autobiographical memories may rely on different neural mechanisms to those established for other types of material in memory.

  7. Neural Correlates of Direct and Indirect Suppression of Autobiographical Memories

    Directory of Open Access Journals (Sweden)

    Saima eNoreen

    2016-03-01

    Full Text Available Research indicates that there are two possible mechanisms by which particular target memories can be intentionally forgotten. Direct suppression, which involves the suppression of the unwanted memory directly, and is dependent on a fronto-hippocampal modulatory process, and, memory substitution, which includes directing one's attention to an alternative memory in order to prevent the unwanted memory from coming to mind, and involves engaging the caudal prefrontal cortex (cPFC and the mid-ventrolateral prefrontal cortex (VLPFC regions. Research to date, however, has investigated the neural basis of memory suppression of relatively simple information. The aim of the current study was to use fMRI to identify the neural mechanisms associated with the suppression of autobiographical memories. In the present study, 22 participants generated memories in response to a series of cue words. In a second session, participants learnt these cue-memory pairings, and were subsequently presented with a cue word and asked either to recall (think or to suppress (no-think the associated memory, or to think of an alternative memory in order to suppress the original memory (memory-substitution. Our findings demonstrated successful forgetting effects in the no-think and memory substitution conditions. Although we found no activation in the dorsolateral prefrontal cortex there was reduced hippocampal activation during direct suppression. In the memory substitution condition, however, we failed to find increased activation in the cPFC and VLPFC regions. Our findings suggest that the suppression of autobiographical memories may rely on different neural mechanisms to those established for other types of material in memory.

  8. Interferometric crosstalk suppression using polarization multiplexing technique and an SOA

    DEFF Research Database (Denmark)

    Liu, Fenghai; Xueyan, Zheng; Pedersen, Rune Johan Skullerud

    2000-01-01

    Interferometric crosstalk can be greatly suppressed at 10Gb/s and 20Gb/s by using a gain saturated SOA and a polarization multiplexing technique that eliminates impairments like waveform and extinction ratio degradation from the SOA.......Interferometric crosstalk can be greatly suppressed at 10Gb/s and 20Gb/s by using a gain saturated SOA and a polarization multiplexing technique that eliminates impairments like waveform and extinction ratio degradation from the SOA....

  9. Strangeness suppression in e+e- light flavour jets

    International Nuclear Information System (INIS)

    Liu Ximing; Sun Xubin

    2007-01-01

    From the simple physical picture of quark combination model, the authors obtain the generate probabilities of various particles and relative ration in e + e - →q 0 (q 0 )-bar→h's process, and find that the relationship between the ration of strange hadron to unstrange hadron γ and the strangeness suppression factor λ. Our results can be used to explain particle ration enhancement observed in experiments without assumption of strangeness suppression factor enhancement. (authors)

  10. Mode of ATM-dependent suppression of chromosome translocation

    Energy Technology Data Exchange (ETDEWEB)

    Yamauchi, Motohiro, E-mail: motoyama@nagasaki-u.ac.jp [Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Suzuki, Keiji; Oka, Yasuyoshi; Suzuki, Masatoshi; Kondo, Hisayoshi; Yamashita, Shunichi [Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan)

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer We addressed how ATM suppresses frequency of chromosome translocation. Black-Right-Pointing-Pointer We found ATM/p53-dependent G1 checkpoint suppresses translocation frequency. Black-Right-Pointing-Pointer We found ATM and DNA-PKcs function in a common pathway to suppress translocation. -- Abstract: It is well documented that deficiency in ataxia telangiectasia mutated (ATM) protein leads to elevated frequency of chromosome translocation, however, it remains poorly understood how ATM suppresses translocation frequency. In the present study, we addressed the mechanism of ATM-dependent suppression of translocation frequency. To know frequency of translocation events in a whole genome at once, we performed centromere/telomere FISH and scored dicentric chromosomes, because dicentric and translocation occur with equal frequency and by identical mechanism. By centromere/telomere FISH analysis, we confirmed that chemical inhibition or RNAi-mediated knockdown of ATM causes 2 to 2.5-fold increase in dicentric frequency at first mitosis after 2 Gy of gamma-irradiation in G0/G1. The FISH analysis revealed that ATM/p53-dependent G1 checkpoint suppresses dicentric frequency, since RNAi-mediated knockdown of p53 elevated dicentric frequency by 1.5-fold. We found ATM also suppresses dicentric occurrence independently of its checkpoint role, as ATM inhibitor showed additional effect on dicentric frequency in the context of p53 depletion and Chk1/2 inactivation. Epistasis analysis using chemical inhibitors revealed that ATM kinase functions in the same pathway that requires kinase activity of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to suppress dicentric frequency. From the results in the present study, we conclude that ATM minimizes translocation frequency through its commitment to G1 checkpoint and DNA double-strand break repair pathway that requires kinase activity of DNA-PKcs.

  11. Application of phase coherent transform to cloud clutter suppression

    Energy Technology Data Exchange (ETDEWEB)

    Ng, L.C. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    This paper describes a tracking algorithm using frame-to-frame correlation with frequency domain clutter suppression. Clutter suppression was mechanized via a `Phase Coherent Transform` (PCT) approach. This approach was applied to explore the feasibility of tracking a post-boost rocket from a low earth orbit satellite with real cloud background data. Simulation results show that the PCT/correlation tracking algorithm can perform satisfactorily at signal-to-clutter ratio (SCR) as low as 5 or 7 dB.

  12. Hearing aid noise suppression and working memory function

    OpenAIRE

    Fischer, Rosa-Linde; Neher, Tobias; Wagener, Kirsten C.

    2017-01-01

    OBJECTIVE: Research findings concerning the relation between benefit from hearing aid (HA) noise suppression and working memory function are inconsistent. The current study thus investigated the effects of three noise suppression algorithms on auditory working memory and the relation with reading span.DESIGN: Using a computer simulation of bilaterally fitted HAs, four settings were tested: (1) unprocessed, (2) directional microphones, (3) single-channel noise reduction and (4) binaural cohere...

  13. Enhanced J/psi suppression due to gluon depletion

    OpenAIRE

    Hwa, R. C.; Pisut, J.; Pisutova, N.

    1997-01-01

    The nonlinear effect of gluon depletion in the collision of large nuclei can be large. It is due to multiple scatterings among comoving partons initiated by primary scattering of partons in the colliding nuclei. The effect can give rise to substantial suppression of $J/\\psi$ production in very large nuclei, even if the linear depletion effect is insignificant for the collisions of nuclei of smaller sizes. This mechanism offers a natural explanation of the enhanced suppression in the Pb-Pb dat...

  14. Effects of cigarette smoking on human aggressive behavior.

    Science.gov (United States)

    Cherek, D R

    1984-01-01

    Nicotine administered by smoking experimental cigarettes produced decreases in two types of aggressive responses elicited by low and high frequency subtractions of money which were attributed to another "person". The suppressing effects of smoking different doses of nicotine on aggressive responses was dose-dependent, in that smoking the high dose of nicotine produced more suppression than smoking the low dose. The ostensible subtraction of money from another "person", the more aggressive response option available to research subjects, was generally more sensitive to the suppressing effects of nicotine than aggressive noise delivery responses. Although this effect could be attributed to another constituent of tobacco, the dose-dependent effect observed with these cigarettes which contained the same amount of tar suggest the effects are due to nicotine. The relatively selective suppression of aggressive behavior observed in humans in the present study is highly consistent with the effects of nicotine observed in a number of infrahuman species. Nicotine has been found to suppress aggressive behavior in ants (Kostowski 1968), rats (Silverman 1971), and cats (Berntson et. al. 1976). In addition, nicotine has been observed to suppress shock elicited fighting in rats (Driscoll, Baettig 1981; Rodgers 1979; Waldbillig 1980) as well as shock elicited biting in monkeys (Hutchinson, Emley 1973). The importance of determining specificity of drug action on aggressive behavior has been repeatedly emphasized in the field of behavioral pharmacology (Sidman 1959; Cook, Kelleher 1963; Thompson, Boren 1977; Miczek, Krsiak 1979). One method employed to evaluate drug specificity and identify a general non-specific excitatory or depressant drug effect is to determine the drug effect on more than one response option which is available to the subject (Sidman 1959). In this study, the same doses of nicotine which suppressed aggressive responding increased nonaggressive monetary

  15. [Punish or cherish: p53, metabolism and tumor suppression].

    Science.gov (United States)

    Albagli, Olivier

    2015-10-01

    The p53 gene is essential for tumor suppression, but how it does so remains unclear. Upon genotoxic or oncogenic stresses, increased p53 activity induces transient cell cycle arrest, senescence or apoptosis, the three cornerstones of the so-called triumvirate. Accordingly, it has long been thought that p53 suppresses tumorigenesis by somehow counteracting cell proliferation or survival. However, several recently described genetically modified mice indicate that p53 can suppress tumorigenesis without triggering these three responses. Rather, as an important mechanism for tumor suppression, these mutant mice point to the ability of p53 to prevent the Warburg effect, that is to dampen glycolysis and foster mitochondrial respiration. Interestingly, these metabolic functions of p53 rely, in part, on its "unstressed" (basal) expression, a feature shared by its mechanistically linked anti-oxydant function. Together, these "conservative" activities of p53 may prevent tumor initiation by promoting and maintaining a normal oxidative metabolism and hence underly the "daily" tumor suppression by p53 in most cells. Conversely, destructive activities elicited by high p53 levels and leading to senescence or apoptosis provide a shield against partially or overtly transformed cells. This last situation, although relatively infrequent throughout life, is usual in experimental settings, which could explain the disproportionally high number of data implicating the triumvirate in tumor suppression by p53. © 2015 médecine/sciences – Inserm.

  16. Context shapes social judgments of positive emotion suppression and expression.

    Science.gov (United States)

    Kalokerinos, Elise K; Greenaway, Katharine H; Casey, James P

    2017-02-01

    It is generally considered socially undesirable to suppress the expression of positive emotion. However, previous research has not considered the role that social context plays in governing appropriate emotion regulation. We investigated a context in which it may be more appropriate to suppress than express positive emotion, hypothesizing that positive emotion expressions would be considered inappropriate when the valence of the expressed emotion (i.e., positive) did not match the valence of the context (i.e., negative). Six experiments (N = 1,621) supported this hypothesis: when there was a positive emotion-context mismatch, participants rated targets who suppressed positive emotion as more appropriate, and evaluated them more positively than targets who expressed positive emotion. This effect occurred even when participants were explicitly made aware that suppressing targets were experiencing mismatched emotion for the context (e.g., feeling positive in a negative context), suggesting that appropriate emotional expression is key to these effects. These studies are among the first to provide empirical evidence that social costs to suppression are not inevitable, but instead are dependent on context. Expressive suppression can be a socially useful emotion regulation strategy in situations that call for it. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  17. Fat suppression applied to MR imaging of the pathologic orbit

    International Nuclear Information System (INIS)

    Simon, J.H.; Kido, D.K.; Ekholm, S.E.; Totterman, S.; Szumowski, J.; Manzione, J.V. Jr.; Joy, S.E.

    1987-01-01

    Previous MR studies of the normal orbit have shown that fat suppression sequences applied at the proper T1-T2 weighting will decrease artifacts from chemical shift, and can be used to enhance contrast in selected anatomic regions. The purpose of this study was to evaluate the clinical application of fat suppression to studies of the pathologic orbit. The studies included conventional imaging sequences and comparative fat suppression sequences through a range of T1-T2 weighting (repetition time [TR] 400 msec, echo time [TE]20 msec, to TR 2,000 msec, TE 90 msec), using the chopper fat suppression technique developed by J. Szumowski and D. Plewes, which requires no postprocessing and no increased scan time to achieve relatively linear fat suppression. Fat suppression was advantageous in determining tumor margins (extension through sclera); increasing diagnostic specificity (fat vs. water content); detailing anatomic relationships along bony margins (particularly in the orbital apex); and for demonstrating true thickness of optic nerve separate from adjacent cerebrospinal fluid and fibrous sheath. Disadvantages included susceptibility to motion artifact and a perception of lower quality due to lower overall orbital signal

  18. The neural basis of suppression and amblyopia in strabismus.

    Science.gov (United States)

    Sengpiel, F; Blakemore, C

    1996-01-01

    The neurophysiological consequences of artificial strabismus in cats and monkeys have been studied for 30 years. However, until very recently no clear picture has emerged of neural deficits that might account for the powerful interocular suppression that strabismic humans experience, nor for the severe amblyopia that is often associated with convergent strabismus. Here we review the effects of squint on the integrative capacities of the primary visual cortex and propose a hypothesis about the relationship between suppression and amblyopia. Most neurons in the visual cortex of normal cats and monkeys can be excited through either eye and show strong facilitation during binocular stimulation with contours of similar orientation in the two eyes. But in strabismic animals, cortical neurons tend to fall into two populations of monocularly excitable cells and exhibit suppressive binocular interactions that share key properties with perceptual suppression in strabismic humans. Such interocular suppression, if prolonged and asymmetric (with input from the squinting eye habitually suppressed by that from the fixating eye), might lead to neural defects in the representation of the deviating eye and hence to amblyopia.

  19. High-Frequency Stimulation at the Subthalamic Nucleus Suppresses Excessive Self-Grooming in Autism-Like Mouse Models.

    Science.gov (United States)

    Chang, Andrew D; Berges, Victoria A; Chung, Sunho J; Fridman, Gene Y; Baraban, Jay M; Reti, Irving M

    2016-06-01

    Approximately one quarter of individuals with an autism spectrum disorder (ASD) display self-injurious behavior (SIB) ranging from head banging to self-directed biting and punching. Sometimes, these behaviors are extreme and unresponsive to pharmacological and behavioral therapies. We have found electroconvulsive therapy (ECT) can produce life-changing results, with more than 90% suppression of SIB frequency. However, these patients typically require frequent maintenance ECT (mECT), as often as every 5 days, to sustain the improvement gained during the acute course. Long-term consequences of such frequent mECT started as early as childhood in some cases are unknown. Accordingly, there is a need for alternative forms of chronic stimulation for these patients. To explore the feasibility of deep brain stimulation (DBS) for intractable SIB seen in some patients with an ASD, we utilized two genetically distinct mouse models demonstrating excessive self-grooming, namely the Viaat-Mecp2(-/y) and Shank3B(-/-) lines, and administered high-frequency stimulation (HFS) via implanted electrodes at the subthalamic nucleus (STN-HFS). We found that STN-HFS significantly suppressed excessive self-grooming in both genetic lines. Suppression occurs both acutely when stimulation is switched on, and persists for several days after HFS is stopped. This effect was not explained by a change in locomotor activity, which was unaffected by STN-HFS. Likewise, social interaction deficits were not corrected by STN-HFS. Our data show STN-HFS suppresses excessive self-grooming in two autism-like mouse models, raising the possibility DBS might be used to treat intractable SIB associated with ASDs. Further studies are required to explore the circuitry engaged by STN-HFS, as well as other potential stimulation sites. Such studies might also yield clues about pathways, which could be modulated by non-invasive stimulatory techniques.

  20. Gender-typical olfactory regulation of sexual behavior in goldfish

    Directory of Open Access Journals (Sweden)

    Makito eKobayashi

    2014-04-01

    Full Text Available It is known that olfaction is essential for the occurrence of sexual behavior in male goldfish. Sex pheromones from ovulatory females elicit male sexual behavior, chasing and sperm releasing act. In female goldfish, ovarian prostaglandin F2α (PGF elicits female sexual behavior, egg releasing act. It has been considered that olfaction does not affect sexual behavior in female goldfish. In the present study, we reexamined the involvement of olfaction in sexual behavior of female goldfish. Olfaction was blocked in male and female goldfish by two methods: nasal occlusion (NO which blocks the reception of olfactants, and olfactory tract section (OTX which blocks transmission of olfactory information from the olfactory bulb to the telencephalon. Sexual behavior of goldfish was induced by administration of PGF to females, an established method for inducing goldfish sexual behavior in both sexes. Sexual behavior in males was suppressed by NO and OTX as previously reported because of lack of pheromone stimulation. In females, NO suppressed sexual behavior but OTX did not affect the occurrence of sexual behavior. Females treated with both NO and OTX performed sexual behavior normally. These results indicate that olfaction is essential in female goldfish to perform sexual behavior as in males but in a different manner. The lack of olfaction in males causes lack of pheromonal stimulation, resulting in no behavior elicited. Whereas the results of female experiments suggest that lack of olfaction in females causes strong inhibition of sexual behavior mediated by the olfactory pathway. Olfactory tract section is considered to block the pathway and remove this inhibition, resulting in the resumption of the behavior. By subtract sectioning of the olfactory tract, it was found that this inhibition was mediated by the medial olfactory tracts, not the lateral olfactory tracts. Thus, it is concluded that goldfish has gender-typical olfactory regulation for sexual

  1. Suppression of pool fires with HRC-125 in a simulated engine nacelle.

    Energy Technology Data Exchange (ETDEWEB)

    Keyser, David R. (INS, Inc., Lexington Park, MD); Hewson, John C.

    2007-06-01

    CFD simulations are conducted to predict the distribution of fire suppressant in an engine nacelle and to predict the suppression of pool fires by the application of this suppressant. In the baseline configuration, which is based on an installed system, suppressant is injected through four nozzles at a rate fast enough to suppress all simulated pool fires. Variations that reduce the mass of the suppression system (reducing the impact of the suppression system on meeting mission needs) are considered, including a reduction in the rate of suppressant injection, a reduction in the mass of suppressant and a reduction in the number of nozzles. In general, these variations should work to reduce the effectiveness of the suppression system, but the CFD results point out certain changes that have negligible impact, at least for the range of phenomena considered here. The results are compared with measurements where available. Comparisons with suppressant measurements are reasonable. A series of twenty-three fire suppression tests were conducted to check the predictions. The pre-test predictions were generally successful in identifying the range of successful suppression tests. In two separate cases, each where one nozzle of the suppression system was capped, the simulation results did indicate a failure to suppress for a condition where the tests indicated successful suppression. When the test-suppressant discharge rate was reduced by roughly 25%, the tests were in agreement with the predictions. That is, the simulations predict a failure to suppress slightly before observed in these cases.

  2. Recreating the scene: an effective way to provide delayed punishment for inappropriate motor behavior.

    OpenAIRE

    Van Houten, R; Rolider, A

    1988-01-01

    A mediated punishment procedure that involved recreating a behavioral sequence by guiding the subject through the behavior in the situation in which it occurred was used to suppress several severe problem behaviors in two developmentally delayed children. The mediational procedure was first used with a 4-year-old autistic boy for biting and then for foot stomping. Next the procedure was used for stealing and hoarding behavior with a multiply handicapped 17-year-old girl. Results indicated tha...

  3. Discounting Behavior

    DEFF Research Database (Denmark)

    Andersen, Steffen; Harrison, Glenn W.; Lau, Morten

    2014-01-01

    We re-evaluate the theory, experimental design and econometrics behind claims that individuals exhibit non-constant discounting behavior. Theory points to the importance of controlling for the non-linearity of the utility function of individuals, since the discount rate is defined over time-dated...

  4. Consumer Behavior

    NARCIS (Netherlands)

    Hoyer, W.D.; MacInnis, D.J.; Pieters, R.

    2013-01-01

    CONSUMER BEHAVIOR combines a foundation in key concepts from marketing, psychology, sociology, and anthropology with a highly practical focus on real-world applications for today's business environment. The new edition of this popular, pioneering text incorporates the latest cutting-edge research

  5. Behavior Modification

    Science.gov (United States)

    Boardman, Randolph M.

    2010-01-01

    In a perfect world, students would never talk back to school staff and never argue or fight with each other. They would complete all their assigned tasks, and disciplinary actions never would be needed. Unfortunately, people don't live in a perfect world. Student behavior is a daily concern. Teachers continue to refer students to the office as a…

  6. Bee venom suppresses methamphetamine-induced conditioned place preference in mice.

    Science.gov (United States)

    Kwon, Young Bae; Li, Jing; Kook, Ji Ae; Kim, Tae Wan; Jeong, Young Chan; Son, Ji Seon; Lee, Hyejung; Kim, Kee Won; Lee, Jang Hern

    2010-02-01

    Although acupuncture is most commonly used for its analgesic effect, it has also been used to treat various drug addictions including cocaine and morphine in humans. This study was designed to investigate the effect of bee venom injection on methamphetamine-induced addictive behaviors including conditioned place preference and hyperlocomotion in mice. Methamphetamine (1 mg/kg) was subcutaneously treated on days 1, 3 and 5 and the acquisition of addictive behaviors was assessed on day 7. After confirming extinction of addictive behaviors on day 17, addictive behaviors reinstated by priming dose of methamphetamine (0.1 mg/kg) was evaluated on day 18. Bee venom (20 microl of 1 mg/ml in saline) was injected to the acupuncture point ST36 on days 1, 3 and 5. Repeated bee venom injections completely blocked development of methamphetamine-induced acquisition and subsequent reinstatement. Single bee venom acupuncture 30 minutes before acquisition and reinstatement test completely inhibited methamphetamine-induced acquisition and reinstatement. Repeated bee venom acupunctures from day 8 to day 12 after methamphetamine-induced acquisition partially but significantly suppressed reinstatement. These findings suggest that bee venom acupuncture has a preventive and therapeutic effect on methamphetamine-induced addiction.

  7. Physical model of lean suppression pressure oscillation phenomena: steam condensation in the light water reactor pressure suppression system (PSS)

    International Nuclear Information System (INIS)

    McCauley, E.W.; Holman, G.S.; Aust, E.; Schwan, H.; Vollbrandt, J.

    1980-01-01

    Using the results of large scale multivent tests conducted by GKSS, a physical model of chugging is developed. The unique combination of accurate digital data and cinematic data has provided the derivation of a detailed, quantified correlation between the dynamic physical variables and the associated two-phase thermo-hydraulic phenomena occurring during lean suppression (chugging) phases of the loss-of-coolant accident in a boiling water reactor pressure suppression system

  8. Neural Substrates of Social Emotion Regulation: A fMRI Study on Imitation and Expressive Suppression to Dynamic Facial Signals

    Directory of Open Access Journals (Sweden)

    Pascal eVrticka

    2013-02-01

    Full Text Available Emotion regulation is crucial for successfully engaging in social interactions. Yet, little is known about the neural mechanisms controlling behavioral responses to emotional expressions perceived in the face of other people, which constitute a key element of interpersonal communication. Here, we investigated brain systems involved in social emotion perception and regulation, using functional magnetic resonance imaging (fMRI in 20 healthy participants who saw dynamic facial expressions of either happiness or sadness, and were asked to either imitate the expression or to suppress any expression on their own face (in addition to a gender judgment control task. fMRI results revealed higher activity in regions associated with emotion (e.g., the insula, motor function (e.g., motor cortex, and theory of mind during imitation. Activity in dorsal cingulate cortex was also increased during imitation, possibly reflecting greater action monitoring or conflict with own feeling states. In addition, premotor regions were more strongly activated during both imitation and suppression, suggesting a recruitment of motor control for both the production and inhibition of emotion expressions. Expressive suppression produced increases in dorsolateral and lateral prefrontal cortex typically related to cognitive control. These results suggest that voluntary imitation and expressive suppression modulate brain responses to emotional signals perceived from faces, by up- and down-regulating activity in distributed subcortical and cortical networks that are particularly involved in emotion, action monitoring, and cognitive control.

  9. Evaporation and condensation heat transfer in a suppression chamber of the water wall type passive containment cooling system

    International Nuclear Information System (INIS)

    Fujii, Tadashi; Kataoka, Yoshiyuki; Murase, Michio

    1996-01-01

    To evaluate the system pressure response of a water wall type containment cooling system, which is one of the passive safety systems, the evaporation and condensation behaviors in a suppression chamber have been experimentally examined. In the system, the suppression pool water evaporates from the pool surface, passing into the wetwell due to pool temperature rise, while steam in the wetwell condenses on the steel containment vessel wall due to the heat release through the wall. The wetwell is a gas phase region in the suppression chamber and its pressure, which is expressed as the sum of the noncondensable gas pressure and saturated steam pressure, is strongly affected by the evaporation heat transfer from the suppression pool surface and condensation heat transfer on the containment vessel wall. Based on the measured temperature profiles near the heat transfer surface and the wetwell pressure using two apparatuses, evaporation and condensation heat transfer coefficients were evaluated. The following results were obtained. (1) Both heat transfer coefficients increased as the ratio of the steam partial pressure to the total pressure increased. (2) Comparison of the results from two types of test apparatuses confirmed that the size of the heat transfer surface did not affect the heat transfer characteristics within these tests. (3) The heat transfer coefficients were expressed by the ratio of the steam to noncondensable gas logarithmic mean concentration, which considered the steam and gas concentration gradient from the heat transfer surface to the wetwell bulk. (author)

  10. Investigating category- and shape-selective neural processing in ventral and dorsal visual stream under interocular suppression.

    Science.gov (United States)

    Ludwig, Karin; Kathmann, Norbert; Sterzer, Philipp; Hesselmann, Guido

    2015-01-01

    Recent behavioral and neuroimaging studies using continuous flash suppression (CFS) have suggested that action-related processing in the dorsal visual stream might be independent of perceptual awareness, in line with the "vision-for-perception" versus "vision-for-action" distinction of the influential dual-stream theory. It remains controversial if evidence suggesting exclusive dorsal stream processing of tool stimuli under CFS can be explained by their elongated shape alone or by action-relevant category representations in dorsal visual cortex. To approach this question, we investigated category- and shape-selective functional magnetic resonance imaging-blood-oxygen level-dependent responses in both visual streams using images of faces and tools. Multivariate pattern analysis showed enhanced decoding of elongated relative to non-elongated tools, both in the ventral and dorsal visual stream. The second aim of our study was to investigate whether the depth of interocular suppression might differentially affect processing in dorsal and ventral areas. However, parametric modulation of suppression depth by varying the CFS mask contrast did not yield any evidence for differential modulation of category-selective activity. Together, our data provide evidence for shape-selective processing under CFS in both dorsal and ventral stream areas and, therefore, do not support the notion that dorsal "vision-for-action" processing is exclusively preserved under interocular suppression. © 2014 Wiley Periodicals, Inc.

  11. The measurement and treatment of suppression in amblyopia.

    Science.gov (United States)

    Black, Joanna M; Hess, Robert F; Cooperstock, Jeremy R; To, Long; Thompson, Benjamin

    2012-12-14

    Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current estimates put the prevalence of amblyopia at approximately 1-3%(1-3), the majority of cases being monocular(2). Amblyopia is most frequently caused by ocular misalignment (strabismus), blur induced by unequal refractive error (anisometropia), and in some cases by form deprivation. Although amblyopia is initially caused by abnormal visual input in infancy, once established, the visual deficit often remains when normal visual input has been restored using surgery and/or refractive correction. This is because amblyopia is the result of abnormal visual cortex development rather than a problem with the amblyopic eye itself(4,5) . Amblyopia is characterized by both monocular and binocular deficits(6,7) which include impaired visual acuity and poor or absent stereopsis respectively. The visual dysfunction in amblyopia is often associated with a strong suppression of the inputs from the amblyopic eye under binocular viewing conditions(8). Recent work has indicated that suppression may play a central role in both the monocular and binocular deficits associated with amblyopia(9,10) . Current clinical tests for suppression tend to verify the presence or absence of suppression rather than giving a quantitative measurement of the degree of suppression. Here we describe a technique for measuring amblyopic suppression with a compact, portable device(11,12) . The device consists of a laptop computer connected to a pair of virtual reality goggles. The novelty of the technique lies in the way we present visual stimuli to measure suppression. Stimuli are shown to the amblyopic eye at high contrast while the contrast of the stimuli shown to the non-amblyopic eye are varied. Patients perform a simple signal/noise task that allows for a precise measurement of the strength of excitatory binocular interactions. The contrast offset at which

  12. Buoyancy suppression in gases at high temperatures

    International Nuclear Information System (INIS)

    Kuczmarski, Maria A.; Gokoglu, Suleyman A.

    2007-01-01

    The computational fluid dynamics code FLUENT was used to study Rayleigh instability at large temperature differences in a sealed gas-filled enclosure with a cold top wall and a heated bottom wall (Benard problem). Both steady state and transient calculations were performed. Instability boundaries depending on the geometry, temperature, and pressure were defined that showed the system tended to become more unstable when the hot-wall temperature increased beyond a certain level, a result of the dampening effect of gas viscosity at higher temperatures. Results also showed that the eventual system stability depended on the final pressure reached at steady state, regardless of how fast the bottom-wall temperature was ramped up to minimize time spent in the unstable region of fluid motion. It was shown that the final system state can differ depending on whether results are obtained via a steady-state or transient calculation, demonstrating that the history of the flow structure development and corresponding temperature fields in this type of system has a profound effect on the final state. Finally, changes in the slope of the pressure-versus-time curve were found to be good indicators of flow pattern changes, and can be a convenient experimental tool for diagnosing the expected changes in flow behavior in such systems

  13. Suppression of asparaginyl endopeptidase attenuates breast cancer-induced bone pain through inhibition of neurotrophin receptors.

    Science.gov (United States)

    Yao, Peng; Ding, Yuanyuan; Han, Zhenkai; Mu, Ying; Hong, Tao; Zhu, Yongqiang; Li, Hongxi

    2017-01-01

    Objective Cancer-induced bone pain is a common clinical problem in breast cancer patients with bone metastasis. However, the mechanisms driving cancer-induced bone pain are poorly known. Recent studies show that a novel protease, asparaginyl endopeptidase (AEP) plays crucial roles in breast cancer metastasis and progression. We aim to determine the functions and targeted suppress of AEP in a mouse model of breast cancer-induced bone pain. Methods Breast cancer cells with AEP knocked-down or overexpression were constructed and implanted into the intramedullary space of the femur to induce pain-like behavior in mice. AEP-specific inhibitors or purified AEP proteins were further used in animal model. The histological characters of femur and pain ethological changes were measured. The expressions of AEP and neurotrophin receptors (p75NTR and TrkA) in dorsal root ganglion and spinal cord were examined. Results Femur radiographs and histological analysis revealed that cells with AEP knocked-down reduced bone destruction and pain behaviors. However, cells with AEP overexpression elevated bone damage and pain behaviors. Further, Western blot results found that the expressions of p75NTR and TrkA in dorsal root ganglions and spinal cords were reduced in mice inoculated with AEP knocked-down cells. Targeted suppression of AEP with specific small compounds significantly reduced the bone pain while purified recombinant AEP proteins increased bone pain. Conclusions AEP aggravate the development of breast cancer bone metastasis and bone pain by increasing the expression of neurotrophin receptors. AEP might be an effective target for treatment of breast cancerinduced bone pain.

  14. Protective effect of Lycium Barbarum polysaccharides on dextromethorphan-induced mood impairment and neurogenesis suppression.

    Science.gov (United States)

    Po, Kevin Kai-Ting; Leung, Joseph Wai-Hin; Chan, Jackie Ngai-Man; Fung, Timothy Kai-Hang; Sánchez-Vidaña, Dalinda Isabel; Sin, Emily Lok-Lam; So, Kwok-Fai; Lau, Benson Wui-Man; Siu, Andrew Man-Hong

    2017-09-01

    Dextromethorphan (DXM) is one of the common drugs abused by adolescents. It is the active ingredient found in cough medicine which is used for suppressing cough. High dosage of DXM can induce euphoria, dissociative effects and even hallucinations. Chronic use of DXM may also lead to depressive-related symptoms. Lycium barbarum, commonly known as wolfberry, has been used as a traditional Chinese medicine for the treatment of ageing-related neurodegenerative diseases. A recent study has shown the potential beneficial effect of Lycium barbarum to reduce depression-like behavior. In the present study, we investigated the role of Lycium barbarum polysaccharide (LBP) to alleviate DXM-induced emotional distress. Sprague Dawley rats were divided into 4 groups (n=6 per group), including the normal control (vehicles only), DXM-treated group (40 mg/kg DXM), LBP-treated group (1 mg/kg LBP) and DXM+ LBP-treated group (40 mg/kg DXM and 1 mg/kg LBP). After two-week treatment, the DXM-treated group showed increased depression-like and social anxiety-like behaviors in the forced swim test and social interaction test respectively. On the other hand, the adverse behavioral effects induced by DXM were reduced by LBP treatment. Histological results showed that LBP treatment alone did not promote hippocampal neurogenesis when compared to the normal control, but LBP could lessen the suppression of hippocampal neurogenesis induced by DXM. The findings provide insights for the potential use of wolfberry as an adjunct treatment option for alleviating mood disturbances during rehabilitation of cough syrup abusers. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. GLP-2 receptor in POMC neurons suppresses feeding behavior and gastric motility

    OpenAIRE

    Guan, Xinfu; Shi, Xuemei; Li, Xiaojie; Chang, Benny; Wang, Yi; Li, Depei; Chan, Lawrence

    2012-01-01

    Glucagon-like peptides (GLP-1/2) are cosecreted from endocrine L cells in the gut and preproglucagonergic neurons in the brain. Peripheral GLP-2 action is essential for maintaining intestinal homeostasis, improving absorption efficiency and blood flow, promoting immune defense, and producing efficacy in treatment of gastrointestinal diseases. However, it is unknown if CNS GLP-2 plays a physiological role in the control of energy homeostasis. Since GLP-1/2 are cotranslated from preproglucagong...

  16. GLP-2 receptor in POMC neurons suppresses feeding behavior and gastric motility

    Science.gov (United States)

    Glucagon-like peptides (GLP-1/2) are cosecreted from endocrine L cells in the gut and preproglucagonergic neurons in the brain. Peripheral GLP-2 action is essential for maintaining intestinal homeostasis, improving absorption efficiency and blood flow, promoting immune defense, and producing efficac...

  17. Persistence and Suppressiveness of Pasteuria penetrans to Meloidogyne arenaria Race.

    Science.gov (United States)

    Cetintas, R; Dickson, D W

    2004-12-01

    The long-term persistence and suppressiveness of Pasteuria penetrans against Meloidogyne arenaria race 1 were investigated in a formerly root-knot nematode suppressive site following 9 years of continuous cultivation of three treatments and 4 years of continuous peanut. The three treatments were two M. arenaria race 1 nonhost crops, bahiagrass (Paspalum notatum cv. Pensacola var. Tifton 9), rhizomal peanut (Arachis glabrata cv. Florigraze), and weed fallow. Two root-knot nematode susceptible weeds commonly observed in weed fallow plots were hairy indigo (Indigofera hirsuta) and alyce clover (Alysicarpus vaginalis). The percentage of J2 with endospores attached reached the highest level of 87% in 2000 in weed fallow, and 63% and 53% in 2002 in bahiagrass and rhizomal peanut, respectively. The percentage of endospore-filled females extracted from peanut roots grown in weed fallow plots increased from nondetectable in 1999 to 56% in 2002, whereas the percentages in bahiagrass and rhizomal peanut plots were 41% and 16%, respectively. Over 4 years, however, there was no strong evidence that endospores densities reached suppressive levels because peanut roots, pods, and pegs were heavily galled, and yields were suppressed. This might be attributed to the discovery of M. javanica infecting peanut in this field in early autumn 2001. A laboratory test confirmed that although the P. penetrans isolate specific to M. arenaria attached to M. javanica J2, no development occurred. In summary, P. penetrans increased on M. arenaria over a 4-year period, but apparently because of infection of M. javanica on peanut at the field site root-knot disease was not suppressed. This was confirmed by a suppressive soil test that showed a higher level of soil suppressiveness than occurred in the field (P

  18. Chromatic induction from surrounding stimuli under perceptual suppression.

    Science.gov (United States)

    Horiuchi, Koji; Kuriki, Ichiro; Tokunaga, Rumi; Matsumiya, Kazumichi; Shioiri, Satoshi

    2014-11-01

    The appearance of colors can be affected by their spatiotemporal context. The shift in color appearance according to the surrounding colors is called color induction or chromatic induction; in particular, the shift in opponent color of the surround is called chromatic contrast. To investigate whether chromatic induction occurs even when the chromatic surround is imperceptible, we measured chromatic induction during interocular suppression. A multicolor or uniform color field was presented as the surround stimulus, and a colored continuous flash suppression (CFS) stimulus was presented to the dominant eye of each subject. The subjects were asked to report the appearance of the test field only when the stationary surround stimulus is invisible by interocular suppression with CFS. The resulting shifts in color appearance due to chromatic induction were significant even under the conditions of interocular suppression for all surround stimuli. The magnitude of chromatic induction differed with the surround conditions, and this difference was preserved regardless of the viewing conditions. The chromatic induction effect was reduced by CFS, in proportion to the magnitude of chromatic induction under natural (i.e., no-CFS) viewing conditions. According to an analysis with linear model fitting, we revealed the presence of at least two kinds of subprocesses for chromatic induction that reside at higher and lower levels than the site of interocular suppression. One mechanism yields different degrees of chromatic induction based on the complexity of the surround, which is unaffected by interocular suppression, while the other mechanism changes its output with interocular suppression acting as a gain control. Our results imply that the total chromatic induction effect is achieved via a linear summation of outputs from mechanisms that reside at different levels of visual processing.

  19. A pilot study examining density of suppression measurement in strabismus.

    Science.gov (United States)

    Piano, Marianne; Newsham, David

    2015-01-01

    Establish whether the Sbisa bar, Bagolini filter (BF) bar, and neutral density filter (NDF) bar, used to measure density of suppression, are equivalent and possess test-retest reliability. Determine whether density of suppression is altered when measurement equipment/testing conditions are changed. Our pilot study had 10 subjects aged ≥18 years with childhood-onset strabismus, no ocular pathologies, and no binocular vision when manifest. Density of suppression upon repeated testing, with clinic lights on/off, and using a full/reduced intensity light source, was investigated. Results were analysed for test-retest reliability, equivalence, and changes with alteration of testing conditions. Test-retest reliability issues were present for the BF bar (median 6 filter change from first to final test, p = 0.021) and NDF bar (median 5 filter change from first to final test, p = 0.002). Density of suppression was unaffected by environmental illumination or fixation light intensity variations. Density of suppression measurements were higher when measured with the NDF bar (e.g. NDF bar = 1.5, medium suppression, vs BF bar = 6.5, light suppression). Test-retest reliability issues may be present for the two filter bars currently still under manufacture. Changes in testing conditions do not significantly affect test results, provided the same filter bar is used consistently for testing. Further studies in children with strabismus having active amblyopia treatment would be of benefit. Despite extensive use of these tests in the UK, this is to our knowledge the first study evaluating filter bar equivalence/reliability.

  20. Depth of suppression in anisometropic amblyopia (with or without microtropia).

    Science.gov (United States)

    Firth, Alison Y; Stevenson, Clare

    2012-01-01

    There are conflicting reports concerning the relationship between depth of suppression and level of amblyopia in strabismics. Little attention has been given to anisometropes. This study examines the density of suppression in anisometropic amblyopes, with or without microtropia, and investigates whether there is a relationship with level of amblyopia. Patients with anisometropia (defined as a difference of 1D or 0.5 D cyl), binocular single vision and a difference in corrected visual acuity of at least 0.1 logMAR between eyes were recalled. The degree of amblyopia was expressed as the interocular difference using the Bailey-Lovie logMAR chart. Stereoacuity (Titmus test), binocular alignment and fixation were recorded. The depth of suppression was measured using the neutral density filter bar together with the Worth four dot test at 4.5m (subtending an angle of 0.5 degrees). Best spherical equivalent (BSE) was calculated to represent anisometropia. Thirteen participants aged 8.3 years to 12.1 years (mean 9.7 years) completed the study. No significant correlation was present (r=0.10, p=0.74) between the depth of suppression and degree of amblyopia. However, there was a correlation between depth of suppression and level of stereoacuity (r=0.59, p=0.03). Six participants had microtropia and showed stronger suppression (p=0.03) and worse stereoacuity (p=0.001) than the pure anisometropes. No evidence was found of a relationship between density of suppression and amblyopia in this cohort of anisometropic amblyopes.

  1. Fire behavior in Mediterranean shrub species (Maquis) | Saglam ...

    African Journals Online (AJOL)

    The prediction of fire behavior in fire prone ecosystems is of vital importance in all phases of fire management including fire prevention, presuppression, suppression and fire use. This paper deals with an experimental burning exercise conducted in the Mediterranean region in Turkey. A series of 18 experimental fires were ...

  2. Optimization of L-shaped tunneling field-effect transistor for ambipolar current suppression and Analog/RF performance enhancement

    Science.gov (United States)

    Li, Cong; Zhao, Xiaolong; Zhuang, Yiqi; Yan, Zhirui; Guo, Jiaming; Han, Ru

    2018-03-01

    L-shaped tunneling field-effect transistor (LTFET) has larger tunnel area than planar TFET, which leads to enhanced on-current ION . However, LTFET suffers from severe ambipolar behavior, which needs to be further optimized for low power and high-frequency applications. In this paper, both hetero-gate-dielectric (HGD) and lightly doped drain (LDD) structures are introduced into LTFET for suppression of ambipolarity and improvement of analog/RF performance of LTFET. Current-voltage characteristics, the variation of energy band diagrams, distribution of band-to-band tunneling (BTBT) generation and distribution of electric field are analyzed for our proposed HGD-LDD-LTFET. In addition, the effect of LDD on the ambipolar behavior of LTFET is investigated, the length and doping concentration of LDD is also optimized for better suppression of ambipolar current. Finally, analog/RF performance of HGD-LDD-LTFET are studied in terms of gate-source capacitance, gate-drain capacitance, cut-off frequency, and gain bandwidth production. TCAD simulation results show that HGD-LDD-LTFET not only drastically suppresses ambipolar current but also improves analog/RF performance compared with conventional LTFET.

  3. β-endorphin modulates the effect of stress on novelty-suppressed feeding

    Directory of Open Access Journals (Sweden)

    Elizabeth T. Barfield

    2013-03-01

    Full Text Available Although stress is implicated in the pathophysiology of mood and anxiety disorders, not all individuals who suffer stressful life events develop psychopathology. Differential susceptibility to stress may be influenced by genetically-mediated differences in hypothalamic-pituitary-adrenal (HPA axis activity and moderation of the stress response by the opioid peptide β-endorphin (β-E. The present study investigated genetic contributions to coping behavior by examining anxious behavior of transgenic mice with varying capacities to synthesize β-E (B6.129S2-Pomctm1Low/J; regulated by insertion of a premature stop codon into one or both copies of the proopiomelanocortin gene, both under normal conditions and following 3 minutes of forced swim. Ten minutes after this stress exposure or a control manipulation, acutely food-deprived female and male transgenic mice were subjected to a novelty-suppressed feeding (NSF test, during which their interaction with an almond slice located in the center of an open field box was measured. There was an interaction between genotype and stress for latency to approach the almond and whether or not the almond was approached, such that mice with low or absent β-E displayed a stronger aversion to novelty-feeding after stress exposure than did mice with normal levels. These data provide evidence for a moderating effect of β-E on the behavioral response to stress. Genotypic differences in anxious behavior emerged when mice were stressed prior to behavioral assessment, suggesting that β-E plays a role in coping behavior. These findings indicate that genetic variability in sensitivity of the β-E system to stress may contribute, at least in part, to heritable differences in stress reactivity as well as vulnerability to stress-related psychopathology.

  4. Behavioral Economics

    OpenAIRE

    Sendhil Mullainathan; Richard H. Thaler

    2000-01-01

    Behavioral Economics is the combination of psychology and economics that investigates what happens in markets in which some of the agents display human limitations and complications. We begin with a preliminary question about relevance. Does some combination of market forces, learning and evolution render these human qualities irrelevant? No. Because of limits of arbitrage less than perfect agents survive and influence market outcomes. We then discuss three important ways in which humans devi...

  5. CONSUMER BEHAVIOR

    OpenAIRE

    Ilie BUDICA; Silvia PUIU; Bogdan Andrei BUDICA

    2010-01-01

    The study of consumers helps firms and organizations improve their marketing strategies by understanding issues such as: the psychology of how consumers think, feel, reason, and select between different alternatives; the psychology of how the consumer is influenced by his or her environment; the behavior of consumers while shopping or making other marketing decisions; limitations in consumer knowledge or information processing abilities influence decisions and marke...

  6. OPEC behavior

    Science.gov (United States)

    Yang, Bo

    This thesis aims to contribute to a further understanding of the real dynamics of OPEC production behavior and its impacts on the world oil market. A literature review in this area shows that the existing studies on OPEC still have some major deficiencies in theoretical interpretation and empirical estimation technique. After a brief background review in chapter 1, chapter 2 tests Griffin's market-sharing cartel model on the post-Griffin time horizon with a simultaneous system of equations, and an innovative hypothesis of OPEC's behavior (Saudi Arabia in particular) is then proposed based on the estimation results. Chapter 3 first provides a conceptual analysis of OPEC behavior under the framework of non-cooperative collusion with imperfect information. An empirical model is then constructed and estimated. The results of the empirical studies in this thesis strongly support the hypothesis that OPEC has operated as a market-sharing cartel since the early 1980s. In addition, the results also provide some support of the theory of non-cooperative collusion under imperfect information. OPEC members collude under normal circumstances and behave competitively at times in response to imperfect market signals of cartel compliance and some internal attributes. Periodic joint competition conduct plays an important role in sustaining the collusion in the long run. Saudi Arabia acts as the leader of the cartel, accommodating intermediate unfavorable market development and punishing others with a tit-for-tat strategy in extreme circumstances.

  7. Behavioral epigenetics.

    Science.gov (United States)

    Moore, David S

    2017-01-01

    Why do we grow up to have the traits we do? Most 20th century scientists answered this question by referring only to our genes and our environments. But recent discoveries in the emerging field of behavioral epigenetics have revealed factors at the interface between genes and environments that also play crucial roles in development. These factors affect how genes work; scientists now know that what matters as much as which genes you have (and what environments you encounter) is how your genes are affected by their contexts. The discovery that what our genes do depends in part on our experiences has shed light on how Nature and Nurture interact at the molecular level inside of our bodies. Data emerging from the world's behavioral epigenetics laboratories support the idea that a person's genes alone cannot determine if, for example, he or she will end up shy, suffering from cardiovascular disease, or extremely smart. Among the environmental factors that can influence genetic activity are parenting styles, diets, and social statuses. In addition to influencing how doctors treat diseases, discoveries about behavioral epigenetics are likely to alter how biologists think about evolution, because some epigenetic effects of experience appear to be transmissible from generation to generation. This domain of research will likely change how we think about the origins of human nature. WIREs Syst Biol Med 2017, 9:e1333. doi: 10.1002/wsbm.1333 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.

  8. Large scale power suppression in a multifield landscape

    International Nuclear Information System (INIS)

    Blanco-Pillado, Jose J.; Frazer, Jonathan; Sousa, Kepa; Dias, Mafalda

    2015-01-01

    Power suppression of the cosmic microwave background on the largest observable scales could provide valuable clues about the particle physics underlying inflation. Here we consider the prospect of power suppression in the context of the multifield landscape. Based on the assumption that our observable universe emerges from a tunnelling event and that the relevant features originate purely from inflationary dynamics, we find that the power spectrum not only contains information on single-field dynamics, but also places strong constraints on all scalar fields present in the theory. We find that the simplest single-field models giving rise to power suppression do not generalise to multifield models in a straightforward way, as the resulting superhorizon evolution of the curvature perturbation tends to erase any power suppression present at horizon crossing. On the other hand, multifield effects do present a means of generating power suppression which to our knowledge has so far not been considered. We propose a mechanism to illustrate this, which we dub flume inflation

  9. Assessing Suppression in Amblyopic Children With a Dichoptic Eye Chart.

    Science.gov (United States)

    Birch, Eileen E; Morale, Sarah E; Jost, Reed M; De La Cruz, Angie; Kelly, Krista R; Wang, Yi-Zhong; Bex, Peter J

    2016-10-01

    Suppression has a key role in the etiology of amblyopia, and contrast-balanced binocular treatment can overcome suppression and improve visual acuity. Quantitative assessment of suppression could have a role in managing amblyopia. We describe a novel eye chart to assess suppression in children. We enrolled 100 children (7-12 years; 63 amblyopic, 25 nonamblyopic with strabismus or anisometropia, 12 controls) in the primary cohort and 22 children (3-6 years; 13 amblyopic, 9 nonamblyopic) in a secondary cohort. Letters were presented on a dichoptic display (5 letters per line). Children wore polarized glasses so that each eye saw a different letter chart. At each position, the identity of the letter and its contrast on each eye's chart differed. Children read 8 lines of letters for each of 3 letter sizes. The contrast balance ratio was the ratio at which 50% of letters seen by the amblyopic eye were reported. Amblyopic children had significantly higher contrast balance ratios for all letter sizes compared to nonamblyopic children and controls, requiring 4.6 to 5.6 times more contrast in the amblyopic eye compared to the fellow eye (P amblyopia treatment was correlated with change in contrast balance ratio (r ranged from 0.43-0.62 for the 3 letter sizes). Severity of suppression can be monitored as part of a routine clinical exam in the management of amblyopia in children.

  10. The perceptual consequences of interocular suppression in amblyopia.

    Science.gov (United States)

    Maehara, Goro; Thompson, Benjamin; Mansouri, Behzad; Farivar, Reza; Hess, Robert F

    2011-11-21

    It is known that information from an amblyopic eye can be strongly suppressed when both eyes are open. The authors investigated the way in which suppression influences the relative perception of suprathreshold contrast and luminance between a person's eyes under dichoptic viewing conditions. Stimuli consisted of four patches of luminance or four patches containing gratings. Two patches were presented to each eye. Ten amblyopes with mild suppression (six strabismic, three anisometropic and strabismic, and one deprivation; mean age, 34.5 years) and three control observers with normal vision (mean age, 33.0 years) matched the appearance of the stimuli presented to each eye. The match involved manipulation of either luminance or contrast. Amblyopes with mild suppression decreased stimulus luminance in the fellow fixing eye or increased luminance in the amblyopic eye to achieve a match (mean matching luminance, 21.1 and 39.6 cd/m(2) for the fellow fixing eye and the amblyopic eye, respectively; standard luminance, 30 cd/m(2)). This interocular mismatch was also observed when luminance was variable and contrast was kept constant (mean matching luminance, 22.8 cd/m(2) for the fellow fixing eye). On the other hand, the amblyopic eye showed no loss of perceived contrast. There was little or no mismatch between the two eyes of control participants with normal binocular vision. Amblyopes have monocular deficits in contrast perception but dichoptic deficits in luminance perception, suggesting that suppression in its mild form involves luminance processing.

  11. Large scale power suppression in a multifield landscape

    Energy Technology Data Exchange (ETDEWEB)

    Blanco-Pillado, Jose J.; Frazer, Jonathan; Sousa, Kepa [Department of Theoretical Physics, Bizkaiako Campusa/Campus de Bizkaia, Posta Kodea 48940, Leioa, Bizkaia (Spain); Dias, Mafalda, E-mail: josejuan.blanco@ehu.es, E-mail: m.dias@sussex.ac.uk, E-mail: j.frazer@ucl.ac.uk, E-mail: kepa.sousa@ehu.es [Astronomy Centre, Department of Physics and Astronomy, School of Maths and Physical Sciences, University of Sussex, Pevensey II Building, Falmer, Brighton, BN1 9QH (United Kingdom)

    2015-08-01

    Power suppression of the cosmic microwave background on the largest observable scales could provide valuable clues about the particle physics underlying inflation. Here we consider the prospect of power suppression in the context of the multifield landscape. Based on the assumption that our observable universe emerges from a tunnelling event and that the relevant features originate purely from inflationary dynamics, we find that the power spectrum not only contains information on single-field dynamics, but also places strong constraints on all scalar fields present in the theory. We find that the simplest single-field models giving rise to power suppression do not generalise to multifield models in a straightforward way, as the resulting superhorizon evolution of the curvature perturbation tends to erase any power suppression present at horizon crossing. On the other hand, multifield effects do present a means of generating power suppression which to our knowledge has so far not been considered. We propose a mechanism to illustrate this, which we dub flume inflation.

  12. Thymoquinone Suppresses IRF-3-Mediated Expression of Type I Interferons via Suppression of TBK1

    Directory of Open Access Journals (Sweden)

    Nur Aziz

    2018-05-01

    Full Text Available Interferon regulatory factor (IRF-3 is known to have a critical role in viral and bacterial innate immune responses by regulating the production of type I interferon (IFN. Thymoquinone (TQ is a compound derived from black cumin (Nigella sativa L. and is known to regulate immune responses by affecting transcription factors associated with inflammation, including nuclear factor-κB (NF-κB and activator protein-1 (AP-1. However, the role of TQ in the IRF-3 signaling pathway has not been elucidated. In this study, we explored the molecular mechanism of TQ-dependent regulation of enzymes in IRF-3 signaling pathways using the lipopolysaccharide (LPS-stimulated murine macrophage-like RAW264.7 cell line. TQ decreased mRNA expression of the interferon genes IFN-α and IFN-β in these cells. This inhibition was due to its suppression of the transcriptional activation of IRF-3, as shown by inhibition of IRF-3 PRD (III-I luciferase activity as well as the phosphorylation pattern of IRF-3 in the immunoblotting experiment. Moreover, TQ targeted the autophosphorylation of TANK-binding kinase 1 (TBK1, an upstream key enzyme responsible for IRF-3 activation. Taken together, these findings suggest that TQ can downregulate IRF-3 activation via inhibition of TBK1, which would subsequently decrease the production of type I IFN. TQ also regulated IRF-3, one of the inflammatory transcription factors, providing a novel insight into its anti-inflammatory activities.

  13. Suppression of immune surveillance in melanoma [Immunotherapy of metastatic melanoma by reversal of immune suppression

    Energy Technology Data Exchange (ETDEWEB)

    Biggs, M. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Eiselein, J. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2001-06-01

    In this paper we develop the hypothesis that a significant fraction of patients with advanced melanoma can be successfully treated with immunotherapy. Reversal of antigen-specific immune suppression to melanoma polypeptide antigens is an essential, first step. We postulate the key regulation of CTL responses resides within the CD4+ T-lymphocytes and macrophage/dendritic cells. There is a pluri-potential cell within this regulatory arm that functions either as a Th1 cell or as a suppressor T-cell, Ths, depending on how antigen is presented. We have shown that poliovirus 1 Sabin will lyse human melanoma cells in tissue culture, and a special "vaccine" prepared from this lysis actively stimulates Ths cell function. The Ths arm of the regulatory system can be down-regulated with cyclophosphamide given 24 hours after the vaccine. The capacity to generate a CTL response is retained. The summary conclusion is that a phase 1 clinical trial in advanced melanoma using the special viral-tumor-lysate followed by cyclophosphamide, plus expanded autologous dendritic cells sensitized with the polypeptide epitopes captained in the viral-lysate will produce beneficial results.

  14. Groups of bats improve sonar efficiency through mutual suppression of pulse emissions.

    Directory of Open Access Journals (Sweden)

    Jenna eJarvis

    2013-06-01

    Full Text Available How bats adapt their sonar behavior to accommodate the noisiness of a crowded day roost is a mystery. Some bats change their pulse acoustics to enhance the distinction between theirs and another bat’s echoes, but additional mechanisms are needed to explain the bat sonar system’s exceptional resilience to jamming by conspecifics. Variable pulse repetition rate strategies offer one potential solution to this dynamic problem, but precisely how changes in pulse rate could improve sonar performance in social settings is unclear. Here we show that bats decrease their emission rates as population density increases, following a pattern that reflects a cumulative mutual suppression of each other’s pulse emissions. Playback of artificially-generated echolocation pulses similarly slowed emission rates, demonstrating that suppression was mediated by hearing the pulses of other bats. Slower emission rates did not support an antiphonal emission strategy but did reduce the relative proportion of emitted pulses that overlapped with another bat’s emissions, reducing the relative rate of mutual interference. The prevalence of acoustic interferences occurring amongst bats was empirically determined to be a linear function of population density and mean emission rates. Consequently as group size increased, small reductions in emission rates spread across the group partially mitigated the increase in interference rate. Drawing on lessons learned from communications networking theory we show how modest decreases in pulse emission rates can significantly increase the net information throughput of the shared acoustic space, thereby improving sonar efficiency for all individuals in a group. We propose that an automated acoustic suppression of pulse emissions triggered by bats hearing each other's emissions dynamically optimizes sonar efficiency for the entire group.

  15. Dissociating the influence of response selection and task anticipation on corticospinal suppression during response preparation.

    Science.gov (United States)

    Duque, Julie; Labruna, Ludovica; Cazares, Christian; Ivry, Richard B

    2014-12-01

    Motor behavior requires selecting between potential actions. The role of inhibition in response selection has frequently been examined in tasks in which participants are engaged in some advance preparation prior to the presentation of an imperative signal. Under such conditions, inhibition could be related to processes associated with response selection, or to more general inhibitory processes that are engaged in high states of anticipation. In Experiment 1, we manipulated the degree of anticipatory preparation. Participants performed a choice reaction time task that required choosing between a movement of the left or right index finger, and used transcranial magnetic stimulation (TMS) to elicit motor evoked potentials (MEPs) in the left hand agonist. In high anticipation blocks, a non-informative cue (e.g., fixation marker) preceded the imperative; in low anticipation blocks, there was no cue and participants were required to divide their attention between two tasks to further reduce anticipation. MEPs were substantially reduced before the imperative signal in high anticipation blocks. In contrast, in low anticipation blocks, MEPs remained unchanged before the imperative signal but showed a marked suppression right after the onset of the imperative. This effect occurred regardless of whether the imperative had signalled a left or right hand response. After this initial inhibition, left MEPs increased when the left hand was selected and remained suppressed when the right hand was selected. We obtained similar results in Experiment 2 except that the persistent left MEP suppression when the left hand was not selected was attenuated when the alternative response involved a non-homologous effector (right foot). These results indicate that, even in the absence of an anticipatory period, inhibitory mechanisms are engaged during response selection, possibly to prevent the occurrence of premature and inappropriate responses during a competitive selection process. Copyright

  16. Dissociating the Influence of Response Selection and Task Anticipation on Corticospinal Suppression During Response Preparation

    Science.gov (United States)

    Duque, Julie; Labruna, Ludovica; Cazares, Christian; Ivry, Richard B.

    2014-01-01

    Motor behavior requires selecting between potential actions. The role of inhibition in response selection has frequently been examined in tasks in which participants are engaged in some advance preparation prior to the presentation of an imperative signal. Under such conditions, inhibition could be related to processes associated with response selection, or to more general inhibitory processes that are engaged in high states of anticipation. In Experiment 1, we manipulated the degree of anticipatory preparation. Participants performed a choice reaction time task that required choosing between a movement of the left or right index finger, and used transcranial magnetic stimulation (TMS) to elicit motor evoked potentials (MEPs) in the left hand agonist. In high anticipation blocks, a non-informative cue (e.g., fixation marker) preceded the imperative; in low anticipation blocks, there was no cue and participants were required to divide their attention between two tasks to further reduce anticipation. MEPs were substantially reduced before the imperative signal in high anticipation blocks. In contrast, in low anticipation blocks, MEPs remained unchanged before the imperative signal but showed a marked suppression right after the onset of the imperative. This effect occurred regardless of whether the imperative had signaled a left or right hand response. After this initial inhibition, left MEPs increased when the left hand was selected and remained suppressed when the right hand was selected. We obtained similar results in Experiment 2 except that the persistent left MEP suppression when the left hand was not selected was attenuated when the alternative response involved a non-homologous effector (right foot). These results indicate that, even in the absence of an anticipatory period, inhibitory mechanisms are engaged during response selection, possibly to prevent the occurrence of premature and inappropriate responses during a competitive selection process. PMID

  17. Dominant Suppression of β1 Integrin by Ectopic CD98-ICD Inhibits Hepatocellular Carcinoma Progression

    Directory of Open Access Journals (Sweden)

    Bo Wu

    2016-11-01

    Full Text Available Hepatocellular carcinoma (HCC is currently the third most common cause of cancer-related death in the Asia-Pacific region. Our previous work showed that knockdown of CD98 significantly inhibits malignant HCC cell phenotypes in vitro and in vivo. The level of CD98 in the membrane is tightly regulated to mediate complex processes associated with cell–cell communication and intracellular signaling. In addition, the intracellular domain of CD98 (CD98-ICD seems to be of vital importance for recycling CD98 to the membrane after it is endocytosed. The intracellular and transmembrane domains of CD98 associate with β-integrins (primarily β1 but also β3, and this association is essential for CD98 mediation of integrin-like signaling and complements dominant suppression of β1-integrin. We speculated that isolated CD98-ICD would similarly suppress β1-integrin activation and inhibit the malignant behaviors of cancer cells. In particular, the exact role of CD98-ICD has not been studied independently in HCC. In this study, we found that ectopic expression of CD98-ICD inhibited the malignant phenotypes of HCC cells, and the mechanism possibly involves β1-integrin suppression. Moreover, the expression levels of CD98, β1-integrin-A (the activated form of β1-integrin and Ki-67 were significantly increased in HCC tissues relative to those of normal liver tissues. Therefore, our preliminary study indicates that ectopic CD98-ICD has an inhibitory role in the malignant development of HCC, and shows that CD98-ICD acts as a dominant negative mutant of CD98 that attenuates β1-integrin activation. CD98-ICD may emerge as a promising candidate for antitumor treatment.

  18. Transboundary Collaborations to Enhance Wildfire Suppression in Protected Areas of the Black Sea Region

    Directory of Open Access Journals (Sweden)

    G. N. Zaimes

    2016-05-01

    Full Text Available For the most effective and efficient management of certain natural resources (e.g. protected areas and disasters (e.g. wildfires transboundary approaches are needed. In addition in the management of protected areas, the role of wildfire should be incorporated, something that was ignored in the past and led to catastrophic wildfires. The Black Sea is a region that wildfires in the protected areas are expected to increase. This has to do with the abandonment of rural areas and the higher temperatures, especially during summer, due to climate change. Interesting is also the fact that some countries of the region have extensive experience while other do not have neither the experience nor the necessary infrastructures to face large wildfires. A transboundary collaboration would be very beneficial to the countries with limited experiences and capacities to suppress wildfires. The objective of this study is to be proactive by developing innovative tools to help suppress wildfires and enhancing the knowledge on wildfires and protected areas. The innovative tools included 4 different research activities and products. Firstly, an online Digital Geodatabase for the six pilot areas was developed. Next forest fire fuels and maps were developed while a forest fire behavior model was run to create the overall fire risk maps for the pilot areas. To estimate water resources and watershed streamflows the hydrologic model SWAT was validated and calibrated for the pilot areas. The final activities included a multi-criteria decision analysis to select the optimal location of the water reservoirs and the use of spatial analyst to provide the optimal routes to reach reservoirs by the fire vehicles. To enhance the responsible agency personnel along with stakeholders knowledge of the region, a Neighborhood Network with regular quarterly meetings was established. Participants for all six project countries were present in the meetings. Overall, new tool that will enhance

  19. Quests for justice and mechanisms of suppression in Flint, Michigan

    DEFF Research Database (Denmark)

    Rutt, Rebecca Leigh; Bluwstein, Jevgeniy

    2017-01-01

    There is widespread acknowledgment of the crisis nature and injustices around water quality and access in Flint since mid-2014. This crisis led to different forms of grassroots activism demanding political accountability, transparency, and redress. However, residents' experiences and their needs...... and demands in response to the crisis have been largely ignored. This article explores the mechanisms of suppression at work in obscuring these needs and demands. Specifically, it sheds light on the role of the public sector, the media, and the academic institutions in reproducing these mechanisms...... of suppression. The article situates the struggles over political accountability within the neoliberalization of public administration and government through emergency management. Capital accumulation can continue and intensifies, whereas emergency management further contributes to suppressing public dissent...

  20. Suppression induction in vivo by a T helper clone?

    DEFF Research Database (Denmark)

    Crispe, I N; Owens, T

    1985-01-01

    We have previously described a helper T cell clone which augments in vivo cytotoxic T cell responses when injected at 10(4) cells per mouse, but not at 10(5) per mouse (Crispe, I. N. et al., Immunology 1984. 52:55). To test whether this dose-response relationship was due to the induction...... of suppression, naive syngeneic mice were injected with 10(5) cloned T helper cells, and their spleen cells were subsequently assayed for suppressive activity in adoptive transfer experiments. Lymphocytes from such mice indeed suppressed an antigen-specific cytotoxic response, but only in the presence...... of the same T helper cell clone freshly added at the time of adoptive transfer. On this basis we argue that the distinction between T helper cell activity and T suppressor-inducer activity corresponds to differences in cell numbers, rather than to two separate cell lineages....

  1. Evaluation of Circulating Current Suppression Methods for Parallel Interleaved Inverters

    DEFF Research Database (Denmark)

    Gohil, Ghanshyamsinh Vijaysinh; Bede, Lorand; Teodorescu, Remus

    2016-01-01

    Two-level Voltage Source Converters (VSCs) are often connected in parallel to achieve desired current rating in multi-megawatt Wind Energy Conversion System (WECS). A multi-level converter can be realized by interleaving the carrier signals of the parallel VSCs. As a result, the harmonic perfor......-mance of the WECS can be significantly improved. However, the interleaving of the carrier signals may lead to the flow of circulating current between parallel VSCs and it is highly desirable to avoid/suppress this unwanted circulating current. A comparative evaluation of the different methods to avoid....../suppress the circulating current between the parallel interleaved VSCs is presented in this paper. The losses and the volume of the inductive components and the semiconductor losses are evaluated for the WECS with different circulating current suppression methods. Multi-objective optimizations of the inductive components...

  2. Azimuth Phase Coding for Range Ambiguity Suppression in SAR

    DEFF Research Database (Denmark)

    Dall, Jørgen; Kusk, Anders

    2004-01-01

    A novel ambiguity suppression technique is proposed. Range ambiguities in synthetic aperture radar (SAR) images are eliminated with an azimuth filter after having applied an azimuth phase modulation to the transmitted pulses and a corresponding demodulation to the received pulses. The technique...... excels by actually eliminating the ambiguities rather than just defocusing them as most other techniques do. This makes the proposed technique applicable to distributed targets. The range ambiguity suppression permits the pulse repetition frequency (PRF) to exceed the upper limit otherwise defined...... by the antenna elevation dimension. The fundamental antenna area constraint still applies, but the PRF can be chosen with more freedom. In addition to ambiguity suppression, potential applications include nadir return elimination and signal-to-noise ratio improvement....

  3. Suppression of radiation mutagenesis by dactinomycin in Chinese hamster cells

    International Nuclear Information System (INIS)

    Tokita, N.; Capenter, S.G.; Chen, D.J.; MacInnes, M.A.; Raju, M.R.

    1985-01-01

    Dactinomycin (AMD) suppression of radiation mutagenesis was investigated using an in vitro mutation assay (6-thioguanine resistance) in Chinese hamster ovary cells. Cells were exposed to acute single doses of x rays followed by 1 hr-treatment with 0.1 or 1 μg/ml AMD. The cell survival curves plotted as a function of x-ray doses were similar for radiation alone and radiation plus AMD. The results suggest that AMD treatment was only slightly mutagenic, however, when given immediately after irradiation, it suppressed radiatiion mutagenesis at higher x-ray dose regions (below 10% survival levels). Higher AMD concentrations appeared more suppressive than lower concentrations. Dose-response data analyzed based on Poisson distribution models suggest the stochastic dependence of x-ray mutagenesis and AMD cytotoxity

  4. Ion energy recovery experiment based on magnetic electro suppression

    International Nuclear Information System (INIS)

    Kim, J.; Stirling, W.L.; Dagenhart, W.K.; Barber, G.C.; Ponte, N.S.

    1980-05-01

    A proof-of-principle experiment on direct recovery of residual hydrogen ions based on a magnetic electron suppression scheme is described. Ions extracted from a source plasma a few kilovolts above the ground potential (approx. 20 A) are accelerated to 40 keV by a negative potential maintained on a neutralizer gas cell. As the residual ions exit the gas cell, they are deflected from the neutral beam by a magnetic field that also suppresses gas cell electrons and then recovered on a ground-potential surface. Under optimum conditions, a recovery efficiency (the ratio of the net recovered current to the available full-energy ion current) of 80% +- 20% has been obtained. Magnetic suppression of the beam plasma electrons was rather easily achieved; however, handling the fractional-energy ions originating from molecular species (H 2 + and H 3 + ) proved to be extremely important to recovery efficiency

  5. Experience with IBS-suppression lattice in RHIC

    International Nuclear Information System (INIS)

    Litvinenko, V.N.; Luo, Y.; Ptitsyn, V.; Satogata, T.; Tepikian, S.; Bai, M.; Bruno, D.; Cameron, P.; Connolly, R.; Della Penna, A.; Drees, A.; Fedotov, A.; Ganetis, G.; Hoff, L.; Louie, W.; Malitsky, N.; Marr, G.; Marusic, A.; Montag, C.; Pilat, F.; Roser, T.; Trbojevic, D.; Tsoupas, N.

    2008-01-01

    An intra-beam scattering (IBS) is the limiting factor of the luminosity lifetime for RHIC operating with heavy ions. In order to suppress the IBS we designed and implemented new lattice with higher betatron tunes. This lattice had been developed during last three years and had been used for gold ions in yellow ring of the RHIC during d-Au part of the RHIC Run-8. The use of this lattice allowed both significant increases in the luminosity lifetime and the luminosity levels via reduction of beta-stars in the IPS. In this paper we report on the development, the tests and the performance of IBS-suppression lattice in RHIC, including the resulting increases in the peak and the average luminosity. We also report on our plans for future steps with the IBS suppression

  6. Stimulus-dependent suppression of chaos in recurrent neural networks

    International Nuclear Information System (INIS)

    Rajan, Kanaka; Abbott, L. F.; Sompolinsky, Haim

    2010-01-01

    Neuronal activity arises from an interaction between ongoing firing generated spontaneously by neural circuits and responses driven by external stimuli. Using mean-field analysis, we ask how a neural network that intrinsically generates chaotic patterns of activity can remain sensitive to extrinsic input. We find that inputs not only drive network responses, but they also actively suppress ongoing activity, ultimately leading to a phase transition in which chaos is completely eliminated. The critical input intensity at the phase transition is a nonmonotonic function of stimulus frequency, revealing a 'resonant' frequency at which the input is most effective at suppressing chaos even though the power spectrum of the spontaneous activity peaks at zero and falls exponentially. A prediction of our analysis is that the variance of neural responses should be most strongly suppressed at frequencies matching the range over which many sensory systems operate.

  7. Adaptive suppression of passive intermodulation in digital satellite transceivers

    Directory of Open Access Journals (Sweden)

    Lu TIAN

    2017-06-01

    Full Text Available For the performance issues of satellite transceivers suffering passive intermodulation interference, a novel and effective digital suppression algorithm is presented in this paper. In contrast to analog approaches, digital passive intermodulation (PIM suppression approaches can be easily reconfigured and therefore are highly attractive for future satellite communication systems. A simplified model of nonlinear distortion from passive microwave devices is established in consideration of the memory effect. The multiple high-order PIM products falling into the receiving band can be described as a bilinear predictor function. A suppression algorithm based on a bilinear polynomial decorrelated adaptive filter is proposed for baseband digital signal processing. In consideration of the time-varying characteristics of passive intermodulation, this algorithm can achieve the rapidness of online interference estimation and low complexity with less consumption of resources. Numerical simulation results show that the algorithm can effectively compensate the passive intermodulation interference, and achieve a high signal-to-interference ratio gain.

  8. A practical dexamethasone suppression test to evaluate hirsute women

    International Nuclear Information System (INIS)

    Wu, C.H.

    1982-01-01

    Fifty-five hirsute women were subjected to a 2-week dexamethasone (DXM) suppression test. The pre- and post-DXM plasma dehydroepiandrosteronesulfate (DS) and testosterone (T) were measured by radioimmunoassay to define the source of androgen excess in hirsute women. Four patients (7%) failed to have adequate adrenal suppression due to failure in medication. Among the 51 patients with adequate adrenal suppression, the source of androgen excess was clearly defined in 48 patients (94%). Seventeen patients (33%) showed ovarian source, 13 patients (26%) had adrenal source, while 18 patients (35%) revealed a mixed adrenal and ovarian source. Normal baseline DS and T levels were noted in 22% of hirsute women and more than half (55%) of them had ovarian androgen excess. Even in 17 patients with normal DS and elevated T, 6 patients (36%) suggested adrenal androgen excess. The source of androgen excess in hirsute women seems evenly distributed among the ovarian, the adrenal, and the mixed group. (author)

  9. Habitat Management to Suppress Pest Populations: Progress and Prospects.

    Science.gov (United States)

    Gurr, Geoff M; Wratten, Steve D; Landis, Douglas A; You, Minsheng

    2017-01-31

    Habitat management involving manipulation of farmland vegetation can exert direct suppressive effects on pests and promote natural enemies. Advances in theory and practical techniques have allowed habitat management to become an important subdiscipline of pest management. Improved understanding of biodiversity-ecosystem function relationships means that researchers now have a firmer theoretical foundation on which to design habitat management strategies for pest suppression in agricultural systems, including landscape-scale effects. Supporting natural enemies with shelter, nectar, alternative prey/hosts, and pollen (SNAP) has emerged as a major research topic and applied tactic with field tests and adoption often preceded by rigorous laboratory experimentation. As a result, the promise of habitat management is increasingly being realized in the form of practical worldwide implementation. Uptake is facilitated by farmer participation in research and is made more likely by the simultaneous delivery of ecosystem services other than pest suppression.

  10. Hearing aid noise suppression and working memory function

    DEFF Research Database (Denmark)

    Neher, Tobias; Wagener, Kirsten C.; Fischer, Rosa-Linde

    2018-01-01

    OBJECTIVE: Research findings concerning the relation between benefit from hearing aid (HA) noise suppression and working memory function are inconsistent. The current study thus investigated the effects of three noise suppression algorithms on auditory working memory and the relation with reading......-to-noise ratio (SNR) improvement. Auditory working memory was assessed at +6 dB SNR using listening span and N-back paradigms. STUDY SAMPLE: Twenty experienced HA users ages 55-80 with large differences in reading span. RESULTS: For the listening span measurements, there was an influence of HA setting....... CONCLUSIONS: HA noise suppression may affect the recognition and recall of speech at positive SNRs, irrespective of individual reading span. Future work should improve the reliability of the auditory working memory measurements....

  11. Vent clearing analysis of a Mark III pressure suppression containment

    International Nuclear Information System (INIS)

    Quintana, R.

    1979-01-01

    An analysis of the vent clearing transient in a Mark III pressure suppression containment after a hypothetical LOCA is carried out. A two-dimensional numerical model solving the transient fluid dynamic equations is used. The geometry of the pressure suppression pool is represented and the pressure and velocity fields in the pool are obtained from the moment the LOCA occurs until the first vent in the drywell wall clears. The results are compared to those obtained with the one-diemensional model used for containment design, with special interest on two-dimensional effects. Some conclusions concerning the effect of the water discharged into the suppression pool through the vents on submerged structures are obtained. Future improvements to the model are suggested. (orig.)

  12. Desensitization of delayed-type hypersensitivity in mice: suppressive environment

    Directory of Open Access Journals (Sweden)

    Takashi Katsura

    1993-01-01

    Full Text Available The systemic injection of high doses of antigen into a preimmunized animal results in transient unresponsiveness of cell-mediated immune responses. This phenomenon is known as desensitization. Serum interleukin 2 (IL-2 activity was found transiently in desensitized mice at 3 h after the antigen challenge. These mice could not reveal antigen nonspecific delayed-type hypersensitivity (DTH 1 d after the challenge. Specific suppression of DTH was observed at later stages. Sera from 3 h desensitized mice showed suppressive effects on DTH in preo immunized mice. Administration of recombinant IL-2 into preimmunized mice led to the failure of development of DTH to antigens. These observations suggest that IL-2 plays an important role in the suppressive environment.

  13. Binocular vision in amblyopia: structure, suppression and plasticity.

    Science.gov (United States)

    Hess, Robert F; Thompson, Benjamin; Baker, Daniel H

    2014-03-01

    The amblyopic visual system was once considered to be structurally monocular. However, it now evident that the capacity for binocular vision is present in many observers with amblyopia. This has led to new techniques for quantifying suppression that have provided insights into the relationship between suppression and the monocular and binocular visual deficits experienced by amblyopes. Furthermore, new treatments are emerging that directly target suppressive interactions within the visual cortex and, on the basis of initial data, appear to improve both binocular and monocular visual function, even in adults with amblyopia. The aim of this review is to provide an overview of recent studies that have investigated the structure, measurement and treatment of binocular vision in observers with strabismic, anisometropic and mixed amblyopia. © 2014 The Authors Ophthalmic & Physiological Optics © 2014 The College of Optometrists.

  14. RISC-Target Interaction: Cleavage and Translational Suppression

    Science.gov (United States)

    van den Berg, Arjen; Mols, Johann; Han, Jiahuai

    2008-01-01

    Summary Small RNA molecules have been known and utilized to suppress gene expression for more than a decade. The discovery that these small RNA molecules are endogenously expressed in many organisms and have a critical role in controlling gene expression have led to the arising of a whole new field of research. Termed small interfering RNA (siRNA) or microRNA (miRNA) these ~22 nt RNA molecules have the capability to suppress gene expression through various mechanisms once they are incorporated in the multi-protein RNA-Induced Silencing Complex (RISC) and interact with their target mRNA. This review introduces siRNAs and microRNAs in a historical perspective and focuses on the key molecules in RISC, structural properties and mechanisms underlying the process of small RNA regulated post-transcriptional suppression of gene expression. PMID:18692607

  15. CAREM 25: Suppression pool cooling and purification system

    International Nuclear Information System (INIS)

    Carlevaris, Rodolfo; Patrignani, Alberto; Vindrola, Carlos; Palmerio, Hector D.; Quiroz, Horacio; Ramilo, Lucia B.

    2000-01-01

    The suppression pool cooling and purification system has the following main functions: purify and cool water from the suppression pool, cool and send water to the residual heat extraction system, and transfer water to the fuel element transference channel. In case of Loss of Coolant Accident (LOCA), the system sends water from the suppression pool to the spray network, thus cooling and reducing pressure in the primary containment. The system has been designed in accordance with the requirements of the following standards: ANSI/ANS 52.1; ANSI/ANS 57.2; ANSI/ANS 56.2; ANSI/ANS 59.1; ANSI/ANS 58.3; ANSI/ANS 58.9; and ANSI/ANS 56.5. The design of the system fulfils all the assigned functions. (author)

  16. CAREM-25. Suppression Pool Cooling and Purification System

    International Nuclear Information System (INIS)

    Carlevaris, Rodolfo; Palmerio, D.; Patrignani, A.; Quiroz, H.; Ramilo, L.; Vindrola, C.

    2000-01-01

    The Suppression Pool Cooling and Purification System has the following main functions: purify and cool water from the Suppression Pool, cool and send water to the Residual Heat Extraction System, and transfer water to the Fuel Element Transference Channel. In case of Loss of Coolant Accident (LOCA), the system sends water from the Suppression Pool to the spray network, thus cooling and reducing pressure in the primary containment.The system has been designed in accordance with the requirements of the following standards ANSI/ANS 52.1 [1], ANSI/ANS 57.2 [2], ANSI/ANS 56.2 [3], ANSI/ANS 59.1 [4] ANSI/ANS 58.3 [5], ANSI/ANS 58.9 [6], and ANSI/ANS 56.5 [7]. The design of the system fulfils all the assigned functions

  17. Suppression of phase synchronisation in network based on cat's brain.

    Science.gov (United States)

    Lameu, Ewandson L; Borges, Fernando S; Borges, Rafael R; Iarosz, Kelly C; Caldas, Iberê L; Batista, Antonio M; Viana, Ricardo L; Kurths, Jürgen

    2016-04-01

    We have studied the effects of perturbations on the cat's cerebral cortex. According to the literature, this cortex structure can be described by a clustered network. This way, we construct a clustered network with the same number of areas as in the cat matrix, where each area is described as a sub-network with a small-world property. We focus on the suppression of neuronal phase synchronisation considering different kinds of perturbations. Among the various controlling interventions, we choose three methods: delayed feedback control, external time-periodic driving, and activation of selected neurons. We simulate these interventions to provide a procedure to suppress undesired and pathological abnormal rhythms that can be associated with many forms of synchronisation. In our simulations, we have verified that the efficiency of synchronisation suppression by delayed feedback control is higher than external time-periodic driving and activation of selected neurons of the cat's cerebral cortex with the same coupling strengths.

  18. Variability in the Geographic Distribution of Fires in Interior Alaska Considering Cause, Human Proximity, and Level of Suppression

    Science.gov (United States)

    Calef, M. P.; Varvak, A.; McGuire, A. D.; Chapin, T.

    2015-12-01

    The boreal forest of Interior Alaska is characterized by frequent extensive wildfires that have been mapped for the past 70 years. Simple predictions based on this record indicate that area burned will increase as a response to climate warming in Alaska. However, two additional factors have affected the area burned in this time record: the Pacific Decadal Oscillation (PDO) switched from cool and moist to warm and dry in the late 1970s and the Alaska Fire Service instituted a fire suppression policy in the late 1980s. Using Geographic Information Systems (GIS) and statistics, this presentation evaluates the variability in area burned and fire ignitions in Interior Alaska in space and time with particular emphasis on the human influence via ignition and suppression. Our analysis shows that while area burned has been increasing by 2.4% per year, the number of lightning ignitions has decreased by 1.9 ignitions per year. Human ignitions account for 50% of all fire ignitions in Interior Alaska and are clearly influenced by human proximity: human fires mostly occur close to settlements, highways and in intense fire suppression zones (which are in turn close to human settlements and roads); fires close to settlements, highways and in intense fire suppression zones burn much shorter than fires further away from this sphere of human influence; and 60% of all human fire ignitions in Interior Alaska are concentrated in the Fairbanks area and thereby strongly influence regional analyses. Fire suppression has effectively reduced area burned since it was implemented but the PDO change has also had some influence. Finally, we found that human fires start earlier in the year and burn for a shorter duration than lightning fires. This study provides insights into the importance of human behavior as well as regional climate patterns as large-scale controls on fires over time and across the Alaskan boreal forest.

  19. Fat suppression failure artifacts at the susceptibility interface on frequency selective fat suppression MR imaging in the head and neck

    International Nuclear Information System (INIS)

    Anzai, Yoshimi; Minoshima, Satoshi; Uno, Kimiichi; Arimizu, Noboru; Lufkin, R.B.; Ishihara, Makiko; Yui, Nobuharu.

    1994-01-01

    Fat suppression MR imaging is a valuable technique mainly used for the orbit, head and neck, and spine, where the high signal from fat can often obscure adjacent pathology. Fat suppression failure artifact manifested as a high signal area without geographic disortion. The purpose of this study was to investigate the frequency and common location of these artifacts in clinical MR imaging and to caution against their misinterpretation. Fat suppression MR imaging of the head and neck was performed in 30 consecutive patients. The artifact was found in the orbital floor (57%), the skull base (10%), and subcutaneous fat (10%), where the air-fat interface is parallel to the static magnetic field direction. The fat signal in the air-fat interface perpendicular to the static magnetic field was well suppressed. This artifact was independent of the duration of TE, frequency/phase encoding direction, and the strength of gradient amplitude, and appeared to be related to the amount of surrounding air. This may simulate pathology if fat suppression is only performed following Gd-DTPA administration. The radiologist should be aware of the presence of artifact by considering the geographic relation to the static magnetic field. (author)

  20. Analysis of Tospovirus NSs Proteins in Suppression of Systemic Silencing.

    Science.gov (United States)

    Hedil, Marcio; Sterken, Mark G; de Ronde, Dryas; Lohuis, Dick; Kormelink, Richard

    2015-01-01

    RNA silencing is a sequence-specific gene regulation mechanism that in plants also acts antiviral. In order to counteract antiviral RNA silencing, viruses have evolved RNA silencing suppressors (RSS). In the case of tospoviruses, the non-structural NSs protein has been identified as the RSS. Although the tomato spotted wilt virus (TSWV) tospovirus NSs protein has been shown to exhibit affinity to long and small dsRNA molecules, its ability to suppress the non-cell autonomous part of RNA silencing has only been studied to a limited extent. Here, the NSs proteins of TSWV, groundnut ringspot virus (GRSV) and tomato yellow ring virus (TYRV), representatives for three distinct tospovirus species, have been studied on their ability and strength to suppress local and systemic silencing. A system has been developed to quantify suppression of GFP silencing in Nicotiana benthamiana 16C lines, to allow a comparison of relative RNA silencing suppressor strength. It is shown that NSs of all three tospoviruses are suppressors of local and systemic silencing. Unexpectedly, suppression of systemic RNA silencing by NSsTYRV was just as strong as those by NSsTSWV and NSsGRSV, even though NSsTYRV was expressed in lower amounts. Using the system established, a set of selected NSsTSWV gene constructs mutated in predicted RNA binding domains, as well as NSs from TSWV isolates 160 and 171 (resistance breakers of the Tsw resistance gene), were analyzed for their ability to suppress systemic GFP silencing. The results indicate another mode of RNA silencing suppression by NSs that acts further downstream the biogenesis of siRNAs and their sequestration. The findings are discussed in light of the affinity of NSs for small and long dsRNA, and recent mutant screen of NSsTSWV to map domains required for RSS activity and triggering of Tsw-governed resistance.

  1. Suppression background device in neutron detection by a scintillation detector

    International Nuclear Information System (INIS)

    Degtyarev, A.P.; Kozyr', Yu.E.; Prokopets, G.A.

    1980-01-01

    A pulse shape discriminator for suppression of cosmic and gamma background as well as for suppression of intrinsic noises of a photomultiplier is described. Identification of signals of background and neutrons is performed by means of comparison of relative intensity of fast and slow components of scintillator luminescence. Basic discriminator flowsheet which contains integrating and differential RC circuits and time-to-amplitude converter is given. The discriminator provides minimum energy of detected neutrons equal to 500 keV when using a FEhU-36 neutron detector with a stilbene crystal [ru

  2. Suppressing proton decay in theories with localised fermions

    International Nuclear Information System (INIS)

    Acharya, B.S.; Valandro, R.

    2005-12-01

    We calculate the contribution to the proton decay amplitude from Kaluza-Klein lepto-quarks in theories with extra dimensions, localised fermions and gauge fields which propagate in the bulk. Such models naturally occur within the context of M theory. In SU(5) models we show that carefully including all such modes gives a distinctive pattern of decays through various channels including a strong suppression of decays into neutrinos or right handed positrons. By contrast there is no such suppression for SO(10). (author)

  3. Effectors from Wheat Rust Fungi Suppress Multiple Plant Defense Responses.

    Science.gov (United States)

    Ramachandran, Sowmya R; Yin, Chuntao; Kud, Joanna; Tanaka, Kiwamu; Mahoney, Aaron K; Xiao, Fangming; Hulbert, Scot H

    2017-01-01

    Fungi that cause cereal rust diseases (genus Puccinia) are important pathogens of wheat globally. Upon infection, the fungus secretes a number of effector proteins. Although a large repository of putative effectors has been predicted using bioinformatic pipelines, the lack of available high-throughput effector screening systems has limited functional studies on these proteins. In this study, we mined the available transcriptomes of Puccinia graminis and P. striiformis to look for potential effectors that suppress host hypersensitive response (HR). Twenty small (wheat, confirming its activity in a homologous system. Overall, this study provides the first evidence for the presence of effectors in Puccinia species suppressing multiple plant defense responses.

  4. Overnight Dexamethasone Suppression Test in the Diagnosis of Cushing's Disease

    Directory of Open Access Journals (Sweden)

    Fatemeh Esfahanian

    2010-08-01

    Full Text Available Realizing the cause of Cushing's Syndrome (CS is one of the most challenging processes in clinical endocrinology. The long high dose dexamethasone suppression test (standard test is costly and need an extended inpatient stay. In this study we want to show the clinical utility of the overnight 8 mg dexamethasone suppression test (DST for differential diagnosis of CS in a referral center. Retrospectively from 2002-2005 we selected the patients of endocrinology ward in Imam hospital who were admitted with the diagnosis of Cushing syndrome and had 8 mg DST (modified test along with classic DST. In modified test a decrease in an 8 AM serum cortisol level of 50% or more is thought to indicate suppression and we compared the results of modified test with standard test. This test had been done on 42 patients: 10 male (23% and 32 female (76%. The mean age of patients was 31.39 (15-63, 32 with proven pituitary Cushing's disease, 7 with primary adrnal tumors and 3 with ectopic ACTH syndrome. The standard test according to 50% suppression of UFC had 90.62% sensitivity, and according to 90% suppression had 43.75% sensitivity. The sensitivity of this test was 71.85% for serum cortisol suppression. The modified test (8 mg overnight DST had 78% sensitivity. All of these tests had 100% specificity for the diagnosis of Cushing's disease. The positive predictive vale (PPV of all of these tests was 100%. The negative predictive value (NPV of modified test for the diagnosis of Cushing's disease was 58.82%. In standard test the NPV of serum cortisol was 52.6%, UFC 50% had 76.9% NPV and UFC 90% had 35.7% NPV. The results of serum cortisol suppression in modified test is better than standard test. Although 50% suppression of UFC in standard test had greater sensitivity than modified test, collecting of urine is difficult, time consuming and needing hospitalization, so we advice modified test that is much simpler and more convenient instead of standard test in the first

  5. Pilot-Induced Oscillation Suppression by Using 1 Adaptive Control

    Directory of Open Access Journals (Sweden)

    Chuan Wang

    2012-01-01

    research activities that aim to alleviate this problem. In this paper, the L1 adaptive controller has been introduced to suppress the PIO, which is caused by rate limiting and pure time delay. Due to its architecture, the L1 adaptive controller will achieve a desired response with fast adaptation. The analysis of PIO and its suppression by L1 adaptive controller are presented in detail in the paper. The simulation results indicate that the L1 adaptive control is efficient in solving this kind of problem.

  6. Suppressing the QCD axion abundance by hidden monopoles

    International Nuclear Information System (INIS)

    Kawasaki, Masahiro

    2015-11-01

    We study the Witten effect of hidden monopoles on the QCD axion dynamics, and show that its abundance as well as isocurvature perturbations can be significantly suppressed if there is a sufficient amount of hidden monopoles. When the hidden monopoles make up a significant fraction of dark matter, the Witten effect suppresses the abundance of axion with the decay constant smaller than 10 12 GeV. The cosmological domain wall problem of the QCD axion can also be avoided, relaxing the upper bound on the decay constant when the Peccei-Quinn symmetry is spontaneously broken after inflation.

  7. Chaos Suppression in Fractional order Permanent Magnet Synchronous Generator in Wind Turbine Systems

    Science.gov (United States)

    Rajagopal, Karthikeyan; Karthikeyan, Anitha; Duraisamy, Prakash

    2017-06-01

    In this paper we investigate the control of three-dimensional non-autonomous fractional-order uncertain model of a permanent magnet synchronous generator (PMSG) via a adaptive control technique. We derive a dimensionless fractional order model of the PMSM from the integer order presented in the literatures. Various dynamic properties of the fractional order model like eigen values, Lyapunov exponents, bifurcation and bicoherence are investigated. The system chaotic behavior for various orders of fractional calculus are presented. An adaptive controller is derived to suppress the chaotic oscillations of the fractional order model. As the direct Lyapunov stability analysis of the robust controller is difficult for a fractional order first derivative, we have derived a new lemma to analyze the stability of the system. Numerical simulations of the proposed chaos suppression methodology are given to prove the analytical results derived through which we show that for the derived adaptive controller and the parameter update law, the origin of the system for any bounded initial conditions is asymptotically stable.

  8. Attentional deployment is not necessary for successful emotion regulation via cognitive reappraisal or expressive suppression.

    Science.gov (United States)

    Bebko, Genna M; Franconeri, Steven L; Ochsner, Kevin N; Chiao, Joan Y

    2014-06-01

    According to appraisal theories of emotion, cognitive reappraisal is a successful emotion regulation strategy because it involves cognitively changing our thoughts, which, in turn, change our emotions. However, recent evidence has challenged the importance of cognitive change and, instead, has suggested that attentional deployment may at least partly explain the emotion regulation success of cognitive reappraisal. The purpose of the current study was to examine the causal relationship between attentional deployment and emotion regulation success. We examined 2 commonly used emotion regulation strategies--cognitive reappraisal and expressive suppression-because both depend on attention but have divergent behavioral, experiential, and physiological outcomes. Participants were either instructed to regulate emotions during free-viewing (unrestricted image viewing) or gaze-controlled (restricted image viewing) conditions and to self-report negative emotional experience. For both emotion regulation strategies, emotion regulation success was not altered by changes in participant control over the (a) direction of attention (free-viewing vs. gaze-controlled) during image viewing and (b) valence (negative vs. neutral) of visual stimuli viewed when gaze was controlled. Taken together, these findings provide convergent evidence that attentional deployment does not alter subjective negative emotional experience during either cognitive reappraisal or expressive suppression, suggesting that strategy-specific processes, such as cognitive appraisal and response modulation, respectively, may have a greater impact on emotional regulation success than processes common to both strategies, such as attention.

  9. In vitro suppression of fungi caused by combinations of apparently non-antagonistic soil bacteria.

    Science.gov (United States)

    de Boer, Wietse; Wagenaar, Anne-Marieke; Klein Gunnewiek, Paulien J A; van Veen, Johannes A

    2007-01-01

    We hypothesized that apparently non-antagonistic soil bacteria may contribute to suppression of fungi during competitive interactions with other bacteria. Four soil bacteria (Brevundimonas sp., Luteibacter sp., Pedobacter sp. and Pseudomonas sp.) that exhibited little or no visible antifungal activity on different agar media were prescribed. Single and mixed strains of these species were tested for antagonism on a nutrient-poor agar medium against the plant pathogenic fungi Fusarium culmorum and Rhizoctonia solani and the saprotrophic fungus Trichoderma harzianum. Single bacterial strains caused little to moderate growth reduction of fungi (quantified as ergosterol), most probably due to nutrient withdrawal from the media. Growth reduction of fungi by the bacterial mixture was much stronger than that by the single strains. This appeared to be mostly due to competitive interactions between the Pseudomonas and Pedobacter strains. We argue that cohabitation of these strains triggered antibiotic production via interspecific interactions and that the growth reduction of fungi was a side-effect caused by the sensitivity of the fungi to bacterial secondary metabolites. Induction of gliding behavior in the Pedobacter strain by other strains was also observed. Our results indicate that apparently non-antagonistic soil bacteria may be important contributors to soil suppressiveness and fungistasis when in a community context.

  10. Suppression and expression of emotion in social and interpersonal outcomes: A meta-analysis.

    Science.gov (United States)

    Chervonsky, Elizabeth; Hunt, Caroline

    2017-06-01

    Emotion expression is critical for the communication of important social information, such as emotional states and behavioral intentions. However, people tend to vary in their level of emotional expression. This meta-analysis investigated the relationships between levels of emotion expression and suppression, and social and interpersonal outcomes. PsycINFO databases, as well as reference lists were searched. Forty-three papers from a total of 3,200 papers met inclusion criteria, allowing for 105 effect sizes to be calculated. Meta-analyses revealed that greater suppression of emotion was significantly associated with poorer social wellbeing, including more negative first impressions, lower social support, lower social satisfaction and quality, and poorer romantic relationship quality. Furthermore, the expression of positive and general/nonspecific emotion was related to better social outcomes, while the expression of anger was associated with poorer social wellbeing. Expression of negative emotion generally was also associated with poorer social outcomes, although this effect size was very small and consisted of mixed results. These findings highlight the importance of considering the role that regulation of emotional expression can play in the development of social dysfunction and interpersonal problems. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  11. Suppression and revival of oscillation in indirectly coupled limit cycle oscillators

    International Nuclear Information System (INIS)

    Sharma, P.R.; Kamal, N.K.; Verma, U.K.; Suresh, K.; Thamilmaran, K.; Shrimali, M.D.

    2016-01-01

    Highlights: • The phenomena of suppression and revival of oscillations are studied in indirectly coupled nonlinear oscillators. • The decay parameter and a feedback factor play a crucial role in emergent dynamical behavior of oscillators. • The critical curves for different dynamical regions are obtained analytically using linear stability analysis. • Electronic circuit experiments demonstrate these emergent dynamical states. - Abstract: We study the phenomena of suppression and revival of oscillations in a system of limit cycle oscillators coupled indirectly via a dynamic local environment. The dynamics of the environment is assumed to decay exponentially with time. We show that for appropriate coupling strength, the decay parameter of the environment plays a crucial role in the emergent dynamics such as amplitude death (AD) and oscillation death (OD). We also show that introducing a feedback factor in the diffusion term revives the oscillations in this system. The critical curves for the regions of different emergent states as a function of coupling strength, decay parameter of the environment and feedback factor in the coupling are obtained analytically using linear stability analysis. These results are found to be consistent with the numerics and are also observed experimentally.

  12. Modeling the suppression of boron transient enhanced diffusion in silicon by substitutional carbon incorporation

    Science.gov (United States)

    Ngau, Julie L.; Griffin, Peter B.; Plummer, James D.

    2001-08-01

    Recent work has indicated that the suppression of boron transient enhanced diffusion (TED) in carbon-rich Si is caused by nonequilibrium Si point defect concentrations, specifically the undersaturation of Si self-interstitials, that result from the coupled out-diffusion of carbon interstitials via the kick-out and Frank-Turnbull reactions. This study of boron TED reduction in Si1-x-yGexCy during 750 °C inert anneals has revealed that the use of an additional reaction that further reduces the Si self-interstitial concentration is necessary to describe accurately the time evolved diffusion behavior of boron. In this article, we present a comprehensive model which includes {311} defects, boron-interstitial clusters, a carbon kick-out reaction, a carbon Frank-Turnbull reaction, and a carbon interstitial-carbon substitutional (CiCs) pairing reaction that successfully simulates carbon suppression of boron TED at 750 °C for anneal times ranging from 10 s to 60 min.

  13. Modeling the suppression of boron transient enhanced diffusion in silicon by substitutional carbon incorporation

    International Nuclear Information System (INIS)

    Ngau, Julie L.; Griffin, Peter B.; Plummer, James D.

    2001-01-01

    Recent work has indicated that the suppression of boron transient enhanced diffusion (TED) in carbon-rich Si is caused by nonequilibrium Si point defect concentrations, specifically the undersaturation of Si self-interstitials, that result from the coupled out-diffusion of carbon interstitials via the kick-out and Frank--Turnbull reactions. This study of boron TED reduction in Si 1-x-y Ge x C y during 750 o C inert anneals has revealed that the use of an additional reaction that further reduces the Si self-interstitial concentration is necessary to describe accurately the time evolved diffusion behavior of boron. In this article, we present a comprehensive model which includes {311} defects, boron-interstitial clusters, a carbon kick-out reaction, a carbon Frank--Turnbull reaction, and a carbon interstitial-carbon substitutional (C i C s ) pairing reaction that successfully simulates carbon suppression of boron TED at 750 o C for anneal times ranging from 10 s to 60 min. copyright 2001 American Institute of Physics

  14. Breast MRI at 7 Tesla with a bilateral coil and robust fat suppression.

    Science.gov (United States)

    Brown, Ryan; Storey, Pippa; Geppert, Christian; McGorty, KellyAnne; Klautau Leite, Ana Paula; Babb, James; Sodickson, Daniel K; Wiggins, Graham C; Moy, Linda

    2014-03-01

    To develop a bilateral coil and fat suppressed T1-weighted sequence for 7 Tesla (T) breast MRI. A dual-solenoid coil and three-dimensional (3D) T1w gradient echo sequence with B1+ insensitive fat suppression (FS) were developed. T1w FS image quality was characterized through image uniformity and fat-water contrast measurements in 11 subjects. Signal-to-noise ratio (SNR) and flip angle maps were acquired to assess the coil performance. Bilateral contrast-enhanced and unilateral high resolution (0.6 mm isotropic, 6.5 min acquisition time) imaging highlighted the 7T SNR advantage. Reliable and effective FS and high image quality was observed in all subjects at 7T, indicating that the custom coil and pulse sequence were insensitive to high-field obstacles such as variable tissue loading. 7T and 3T image uniformity was similar (P=0.24), indicating adequate 7T B1+ uniformity. High 7T SNR and fat-water contrast enabled 0.6 mm isotropic imaging and visualization of a high level of fibroglandular tissue detail. 7T T1w FS bilateral breast imaging is feasible with a custom radiofrequency (RF) coil and pulse sequence. Similar image uniformity was achieved at 7T and 3T, despite different RF field behavior and variable coil-tissue interaction due to anatomic differences that might be expected to alter magnetic field patterns. Copyright © 2013 Wiley Periodicals, Inc.

  15. Promotion or suppression of glucose isomerization in subcritical aqueous straight- and branched-chain alcohols.

    Science.gov (United States)

    Gao, Da-Ming; Kobayashi, Takashi; Adachi, Shuji

    2015-01-01

    The influence of water-miscible alcohols (methanol, 1-propanol, 2-propanol, and t-butyl alcohol) on the isomerization of glucose to fructose and mannose was investigated under subcritical aqueous conditions (180-200 °C). Primary and secondary alcohols promoted the conversion and isomerization of glucose to afford fructose and mannose with high and low selectivity, respectively. On the other hand, the decomposition (side-reaction) of glucose was suppressed in the presence of the primary and secondary alcohols compared with that in subcritical water. The yield of fructose increased with increasing concentration of the primary and secondary alcohols, and the species of the primary and secondary alcohols tested had little effect on the isomerization behavior of glucose. In contrast, the isomerization of glucose was suppressed in subcritical aqueous t-butyl alcohol. Both the conversion of glucose and the yield of fructose decreased with increasing concentration of t-butyl alcohol. In addition, mannose was not detected in reactions using subcritical aqueous t-butyl alcohol.

  16. Active unsteady aerodynamic suppression of rotating stall in an incompressible flow centrifugal compressor with vaned diffuser

    Science.gov (United States)

    Lawless, Patrick B.; Fleeter, Sanford

    1991-01-01

    A mathematical model is developed to analyze the suppression of rotating stall in an incompressible flow centrifugal compressor with a vaned diffuser, thereby addressing the important need for centrifugal compressor rotating stall and surge control. In this model, the precursor to to instability is a weak rotating potential velocity perturbation in the inlet flow field that eventually develops into a finite disturbance. To suppress the growth of this potential disturbance, a rotating control vortical velocity disturbance is introduced into the impeller inlet flow. The effectiveness of this control is analyzed by matching the perturbation pressure in the compressor inlet and exit flow fields with a model for the unsteady behavior of the compressor. To demonstrate instability control, this model is then used to predict the control effectiveness for centrifugal compressor geometries based on a low speed research centrifugal compressor. These results indicate that reductions of 10 to 15 percent in the mean inlet flow coefficient at instability are possible with control waveforms of half the magnitude of the total disturbance at the inlet.

  17. CONSUMER BEHAVIOR

    Directory of Open Access Journals (Sweden)

    Ilie BUDICA

    2010-03-01

    Full Text Available The study of consumers helps firms and organizations improve their marketing strategies by understanding issues such as: the psychology of how consumers think, feel, reason, and select between different alternatives; the psychology of how the consumer is influenced by his or her environment; the behavior of consumers while shopping or making other marketing decisions; limitations in consumer knowledge or information processing abilities influence decisions and marketing outcome; how consumer motivation and decision strategies differ between products that differ in their level of importance or interest that they entail for the consumer; and how marketers can adapt and improve their marketing campaigns and marketing strategies to more effectively reach the consumer.

  18. Reproductive bribing and policing as evolutionary mechanisms for the suppression of within-group selfishness.

    Science.gov (United States)

    Reeve, H K; Keller, L

    1997-07-01

    We show that a new, simple, and robust general mechanism for the social suppression of within-group selfishness follows from Hamilton's rule applied in a multilevel selection approach to asymmetrical, two-person groups: If it pays a group member to behave selfishly (i.e., increase its share of the group's reproduction, at the expense of group productivity), then its partner will virtually always be favored to provide a reproductive "bribe" sufficient to remove the incentive for the selfish behavior. The magnitude of the bribe will vary directly with the number of offspring (or other close kin) potentially gained by the selfish individual and inversely with both the relatedness r between the interactants and the loss in group productivity because of selfishness. This bribe principle greatly extends the scope for cooperation within groups. Reproductive bribing is more likely to be favored over social policing for dominants rather than subordinates and as intragroup relatedness increases. Finally, analysis of the difference between the group optimum for an individual's behavior and the individual's inclusive fitness optimum reveals a paradoxical feedback loop by which bribing and policing, while nullifying particular selfish acts, automatically widen the separation of individual and group optima for other behaviors (i.e., resolution of one conflict intensifies others).

  19. Memory-induced resonancelike suppression of spike generation in a resonate-and-fire neuron model

    Science.gov (United States)

    Mankin, Romi; Paekivi, Sander

    2018-01-01

    The behavior of a stochastic resonate-and-fire neuron model based on a reduction of a fractional noise-driven generalized Langevin equation (GLE) with a power-law memory kernel is considered. The effect of temporally correlated random activity of synaptic inputs, which arise from other neurons forming local and distant networks, is modeled as an additive fractional Gaussian noise in the GLE. Using a first-passage-time formulation, in certain system parameter domains exact expressions for the output interspike interval (ISI) density and for the survival probability (the probability that a spike is not generated) are derived and their dependence on input parameters, especially on the memory exponent, is analyzed. In the case of external white noise, it is shown that at intermediate values of the memory exponent the survival probability is significantly enhanced in comparison with the cases of strong and weak memory, which causes a resonancelike suppression of the probability of spike generation as a function of the memory exponent. Moreover, an examination of the dependence of multimodality in the ISI distribution on input parameters shows that there exists a critical memory exponent αc≈0.402 , which marks a dynamical transition in the behavior of the system. That phenomenon is illustrated by a phase diagram describing the emergence of three qualitatively different structures of the ISI distribution. Similarities and differences between the behavior of the model at internal and external noises are also discussed.

  20. Functional role for suppression of the insular-striatal circuit in modulating interoceptive effects of alcohol.

    Science.gov (United States)

    Jaramillo, Anel A; Agan, Verda E; Makhijani, Viren H; Pedroza, Stephen; McElligott, Zoe A; Besheer, Joyce

    2017-09-27

    The insular cortex (IC) is a region proposed to modulate, in part, interoceptive states and motivated behavior. Interestingly, IC dysfunction and deficits in interoceptive processing are often found among individuals with substance-use disorders. Furthermore, the IC projects to the nucleus accumbens core (AcbC), a region known to modulate the discriminative stimulus/interoceptive effects of alcohol and other drug-related behaviors. Therefore, the goal of the present work was to investigate the possible role of the IC ➔ AcbC circuit in modulating the interoceptive effects of alcohol. Thus, we utilized a chemogenetic technique (hM4D i designer receptor activation by designer drugs) to silence neuronal activity in the IC of rats trained to discriminate alcohol (1 g/kg, IG) versus water using an operant or Pavlovian alcohol discrimination procedure. Chemogenetic silencing of the IC or IC ➔ AcbC neuronal projections resulted in potentiated sensitivity to the interoceptive effects of alcohol in both the operant and Pavlovian tasks. Together, these data provide critical evidence for the nature of the complex IC circuitry and, specifically, suppression of the insular-striatal circuit in modulating behavior under a drug stimulus control. © 2017 Society for the Study of Addiction.

  1. Suppression of metabolic activity caused by infantile strabismus and strabismic amblyopia in striate visual cortex of macaque monkeys.

    Science.gov (United States)

    Wong, Agnes M F; Burkhalter, Andreas; Tychsen, Lawrence

    2005-02-01

    Suppression is a major sensorial abnormality in humans and monkeys with infantile strabismus. We previously reported evidence of metabolic suppression in the visual cortex of strabismic macaques, using the mitochondrial enzyme cytochrome oxidase as an anatomic label. The purpose of this study was to further elucidate alterations in cortical metabolic activity, with or without amblyopia. Six macaque monkeys were used in the experiments (four strabismic and two control). Three of the strabismic monkeys had naturally occurring, infantile strabismus (two esotropic, one exotropic). The fourth strabismic monkey had infantile microesotropia induced by alternating monocular occlusion in the first months of life. Ocular motor behaviors and visual acuity were tested after infancy in each animal, and development of stereopsis was recorded during infancy in one strabismic and one control monkey. Ocular dominance columns (ODCs) of the striate visual cortex (area V1) were labeled using cytochrome oxidase (CO) histochemistry alone, or CO in conjunction with an anterograde tracer ([H 3 ]proline or WGA-HRP) injected into one eye. Each of the strabismic monkeys showed inequalities of metabolic activity in ODCs of opposite ocularity, visible as rows of lighter CO staining, corresponding to ODCs of lower metabolic activity, alternating with rows of darker CO staining, corresponding to ODCs of higher metabolic activity. In monkeys who had infantile strabismus and unilateral amblyopia, lower metabolic activity was found in (suppressed) ODCs driven by the nondominant eye in each hemisphere. In monkeys who had infantile esotropia and alternating fixation (no amblyopia), metabolic activity was lower in ODCs driven by the ipsilateral eye in each hemisphere. The suppression included a monocular core zone at the center of ODCs and binocular border zones at the boundaries of ODCs. This suppression was not evident in the monocular lamina of the LGN, indicating an intracortical rather than

  2. Exploring gender differences in the link between weight suppression and eating pathology.

    Science.gov (United States)

    Burnette, C Blair; Simpson, Courtney C; Mazzeo, Suzanne E

    2017-12-01

    Weight suppression (WS), the difference in one's highest weight (excluding pregnancy) and current weight at current height, is associated with the onset of eating disorders. Previous research has explored the influence of WS in predominantly clinical, female samples. However, the transition to college is a particularly high-risk time for weight gain and the development of eating pathology and men with eating disorders often have higher premorbid weights. This study investigated the associations of WS and dimensions of eating pathology in an undergraduate sample (N=859) and examined the effect of gender. Results demonstrated that higher levels of WS were associated with more dietary restraint (p=0.004) and more frequent purging behaviors (peating through dietary restraint for both men and women (peating. This approach might be particularly beneficial with college students due to their heightened risk of eating and weight disturbances. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. An efficient approach to suppress the negative role of contrarian oscillators in synchronization

    Science.gov (United States)

    Zhang, Xiyun; Ruan, Zhongyuan; Liu, Zonghua

    2013-09-01

    It has been found that contrarian oscillators usually take a negative role in the collective behaviors formed by conformist oscillators. However, experiments revealed that it is also possible to achieve a strong coherence even when there are contrarians in the system such as neuron networks with both excitable and inhibitory neurons. To understand the underlying mechanism of this abnormal phenomenon, we here consider a complex network of coupled Kuramoto oscillators with mixed positive and negative couplings and present an efficient approach, i.e., tit-for-tat strategy, to suppress the negative role of contrarian oscillators in synchronization and thus increase the order parameter of synchronization. Two classes of contrarian oscillators are numerically studied and a brief theoretical analysis is provided to explain the numerical results.

  4. Patterns and Predictors of Tic Suppressibility in Youth With Tic Disorders.

    Science.gov (United States)

    Conelea, Christine A; Wellen, Brianna; Woods, Douglas W; Greene, Deanna J; Black, Kevin J; Specht, Matthew; Himle, Michael B; Lee, Han-Joo; Capriotti, Matthew

    2018-01-01

    Tic suppression is the primary target of tic disorder treatment, but factors that influence voluntary tic inhibition are not well understood. Several studies using the Tic Suppression Task have demonstrated significant inter-individual variability in tic suppressibility but have individually been underpowered to address correlates of tic suppression. The present study explored patterns and clinical correlates of reward-enhanced tic suppression in youth with tic disorders using a large, pooled dataset. Individual-level data from nine studies using the Tic Suppression Task were pooled, yielding a sample of 99 youth with tic disorders. Analyses examined patterns of tic suppressibility and the relationship between tic suppressibility and demographic and clinical characteristics. A large majority of youth demonstrated a high degree of tic suppression, but heterogeneous patterns of tic suppressibility were also observed. Better tic suppressibility was related to older age and more frequent tics but unrelated to other clinical variables, including presence of psychiatric comorbidity, psychotropic medication status, tic and premonitory urge severity, and self-rated tic suppressibility. The mechanisms underlying the observed heterogeneity in reward-enhanced tic suppressibility warrant further investigation. The Tic Suppression Task is a promising method for testing mechanistic hypotheses related to tic suppression.

  5. Expressive Suppression and Enhancement During Music-Elicited Emotions in Younger and Older Adults

    Directory of Open Access Journals (Sweden)

    Sandrine eVieillard

    2015-02-01

    Full Text Available When presented with emotional visual scenes, older adults have been found to be equally capable to regulate emotion expression as younger adults, corroborating the view that emotion regulation skills are maintained or even improved in later adulthood. However, the possibility that gaze direction might help achieve an emotion control goal has not been taken into account, raising the question whether the effortful processing of expressive regulation is really spared from the general age-related decline. Since it does not allow perceptual attention to be redirected away from the emotional source, music provides a useful way to address this question. In the present study, affective, behavioral and physiological consequences of free expression of emotion, expressive suppression and expressive enhancement were measured in 31 younger and 30 older adults while they listened to positive and negative musical excerpts. The main results indicated that compared to younger adults, older adults reported experiencing less emotional intensity in response to negative music during the free expression of emotion condition. No age difference was found in the ability to amplify or reduce emotional expressions. However, an age-related decline in the ability to reduce the intensity of emotional state and an age-related increase in physiological reactivity were found when participants were instructed to suppress negative expression. Taken together, the current data support previous findings suggesting an age-related change in response to music. They also corroborate the observation that older adults are as efficient as younger adults at controlling behavioral expression. But most importantly, they suggest that when faced with auditory sources of negative emotion, older age does not always confer a better ability to regulate emotions.

  6. Weight Suppression Predicts Time to Remission from Bulimia Nervosa

    Science.gov (United States)

    Lowe, Michael R.; Berner, Laura A.; Swanson, Sonja A.; Clark, Vicki L.; Eddy, Kamryn T.; Franko, Debra L.; Shaw, Jena A.; Ross, Stephanie; Herzog, David B.

    2011-01-01

    Objective: To investigate whether, at study entry, (a) weight suppression (WS), the difference between highest past adult weight and current weight, prospectively predicts time to first full remission from bulimia nervosa (BN) over a follow-up period of 8 years, and (b) weight change over time mediates the relationship between WS and time to first…

  7. Suppression of developmental anomalies by maternal macrophages in mice

    International Nuclear Information System (INIS)

    Nomura, T.; Hata, S.; Kusafuka, T.

    1990-01-01

    We tested whether nonspecific tumoricidal immune cells can suppress congenital malformations by killing precursor cells destined to cause such defects. Pretreatment of pregnant ICR mice with synthetic (Pyran copolymer) and biological (Bacillus Calmette-Guerin) agents significantly suppressed radiation- and chemical-induced congenital malformations (cleft palate, digit anomalies, tail anomalies, etc.). Such suppressive effects were associated with the activation of maternal macrophages by these agents, but were lost either after the disruption of activated macrophages by supersonic waves or by inhibition of their lysosomal enzyme activity with trypan blue. These results indicate that a live activated macrophage with active lysosomal enzymes can be an effector cell to suppress maldevelopment. A similar reduction by activated macrophages was observed in strain CL/Fr, which has a high spontaneous frequency of cleft lips and palates. Furthermore, Pyran-activated maternal macrophages could pass through the placenta, and enhanced urethane-induced cell killing (but not somatic mutation) in the embryo. It is likely that a maternal immunosurveillance system eliminating preteratogenic cells allows for the replacement with normal totipotent blast cells during the pregnancy to protect abnormal development

  8. Differences in xylogenesis between dominant and suppressed trees.

    Science.gov (United States)

    Liu, Shushan; Li, Xiaoxia; Rossi, Sergio; Wang, Lily; Li, Wei; Liang, Eryuan; Leavitt, Steven W

    2018-05-01

    Most dendroecological studies focus on dominant trees, but little is known about the growing season of trees belonging to different size classes and their sensitivity to biotic factors. The objective of this study was to compare the dynamics of xylem formation between dominant and suppressed trees of Abies fabri of similar age growing in the Gongga Mountains, southeastern Tibetan Plateau, and to identify the association between xylem growth and climate. The timing and duration of xylogenesis in histological sections were investigated weekly during the 2013-2015 growing seasons. Our investigation found that timing and duration of xylogenesis varied with canopy position and its associated tree size. Xylogenesis started 6-14 days earlier, and ended 5-11 days later in dominant trees than in suppressed trees, resulting in a significantly longer growing season. Dominant trees also exhibited higher temperature sensitivity of tracheid production rate than suppressed trees. The observed differences in xylogenesis among trees suggested that competition affects tree growth by reducing the growing period in suppressed trees. Representative climate-growth relationships should involve trees of all size classes when evaluating the effects of the environment on forest dynamics. © 2018 Botanical Society of America.

  9. Mastication suppresses initial gastric emptying by modulating gastric activity.

    Science.gov (United States)

    Ohmure, H; Takada, H; Nagayama, K; Sakiyama, T; Tsubouchi, H; Miyawaki, S

    2012-03-01

    Because various mastication-related factors influence gastric activity, the functional relationship between mastication and gastric function has not been fully elucidated. To investigate the influence of mastication on gastric emptying and motility, we conducted a randomized trial to compare the effects of mastication on gastric emptying and gastric myoelectrical activity under conditions that excluded the influences of food comminution, taste, and olfaction. A (13)C-acetate breath test with electrogastrography and electrocardiography was performed in 14 healthy men who ingested a test meal with or without chewing gum. Autonomic nerve activity was evaluated by fluctuation analysis of heart rate. Gastric emptying was significantly delayed in the 'ingestion with mastication' group. Gastric myoelectrical activity was significantly suppressed during mastication and increased gradually in the post-mastication phase. A decrease in the high-frequency power of heart rate variability was observed coincidentally with gastric myoelectrical activity suppression. These findings suggest that initial gastric emptying is suppressed by mastication, and that the suppression is caused by mastication-induced inhibition of gastric activity (UMIN Clinical Trial Registration no. UMIN000005351).

  10. Natural suppression of Meloidogyne incognita by Pasteuria penetrans in cotton

    Science.gov (United States)

    The endospore-forming bacterium Pasteuria penetrans is an obligate parasite of root-knot nematodes (Meloidogyne spp.). This bacterium is commonly found in agricultural soils and has been associated with suppression of Meloidogyne spp. In a field site naturally infested with both P. penetrans and M...

  11. Young Adult Psychological Outcome After Puberty Suppression and Gender Reassignment

    NARCIS (Netherlands)

    de Vries, A.L.C.; McGuire, J.K.; Steensma, T.D.; Wagenaar, E.C.F.; Doreleijers, T.A.H.; Cohen-Kettenis, P.T.

    2014-01-01

    BACKGROUND: In recent years, puberty suppression by means of gonadotropin-releasing hormone analogs has become accepted in clinical management of adolescents who have gender dysphoria (GD). The current study is the first longer-term longitudinal evaluation of the effectiveness of this approach.

  12. Hazardous fuel treatments, suppression cost impacts, and risk mitigation

    Science.gov (United States)

    Matthew P. Thompson; Michael S. Hand; Julie W. Gilbertson-Day; Nicole M. Vaillant; Darek J. Nalle

    2013-01-01

    Land management agencies face uncertain tradeoffs regarding investments in preparedness and fuels management versus future suppression costs and impacts to valued resources and assets. Prospective evaluation of fuel treatments allows for comparison of alternative treatment strategies in terms of socioeconomic and ecological impacts, and can facilitate tradeoff analysis...

  13. Baicalein and U0126 suppress bladder cancer proliferation via ...

    African Journals Online (AJOL)

    RT-PCR) and western blot. Results: Baicalein and U0126 suppressed bladder cancer cell T24 proliferation by blocking cell cycle in G0~G1 phase. TUNEL and Annexin V/PI detection showed both baicalein and U0126 induced T24 cell ...

  14. Seeding method and rate influence on weed suppression in aerobic ...

    African Journals Online (AJOL)

    High weed pressure is amongst the major constraints to the extensive adoption of aerobic rice system as a water-wise technique. Towards developing a sustainable weed management strategy, seeding method and rate may substantially contribute to weed suppression and reduce herbicide use and weeding cost. A trough ...

  15. Aqueous Extract of Oldenlandia diffusa Suppresses LPS-Induced ...

    African Journals Online (AJOL)

    ... potential transcriptional factor for regulating the expression of iNOS, COX-2 and TNF-α. As expected, AEOD suppressed the LPS-induced degradation and phosphorylation of IκBα and sustained the expression of p65 in the cytosol. Furthermore, AEOD substantially inhibited the LPS-induced DNA binding activity of NF-κB.

  16. Engineered Surfaces to Control Secondary Electron Yield for Multipactor Suppression

    Science.gov (United States)

    2017-09-14

    Air Force Institute of Technology AFIT Scholar Theses and Dissertations 9-14-2017 Engineered Surfaces to Control Secondary Electron Yield for...Multipactor Suppression James M. Sattler Follow this and additional works at: https://scholar.afit.edu/etd Part of the Electrical and Electronics Commons... TECHNOLOGY Wright-Patterson Air Force Base, Ohio DISTRIBUTION STATEMENT A. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED

  17. Suppressing the Morning Rise in Cortisol Impairs Free Recall

    Science.gov (United States)

    Rimmele, Ulrike; Meier, Flurina; Lange, Tanja; Born, Jan

    2010-01-01

    Elevated glucocorticoid levels impair memory retrieval. We investigated whether retrieval under naturally elevated glucocorticoid levels, i.e., during the morning rise in cortisol can be improved by suppressing cortisol. In a crossover study 16 men retrieved emotional and neutral texts and pictures (learned 3 d earlier) 30 min after morning…

  18. Maturation of cognitive control: delineating response inhibition and interference suppression.

    Directory of Open Access Journals (Sweden)

    Christopher R Brydges

    Full Text Available Cognitive control is integral to the ability to attend to a relevant task whilst suppressing distracting information or inhibiting prepotent responses. The current study examined the development of these two subprocesses by examining electrophysiological indices elicited during each process. Thirteen 18 year-old adults and thirteen children aged 8-11 years (mean=9.77 years completed a hybrid Go/Nogo flanker task while continuous EEG data were recorded. The N2 topography for both response inhibition and interference suppression changed with increasing age. The neural activation associated with response inhibition became increasingly frontally distributed with age, and showed decreases of both amplitude and peak latency from childhood to adulthood, possibly due to reduced cognitive demands and myelination respectively occurring during this period. Interestingly, a significant N2 effect was apparent in adults, but not observed in children during trials requiring interference suppression. This could be due to more diffuse activation in children, which would require smaller levels of activation over a larger region of the brain than is reported in adults. Overall, these results provide evidence of distinct maturational processes occurring throughout late childhood and adolescence, highlighting the separability of response inhibition and interference suppression.

  19. Puberty suppression in gender identity disorder: the Amsterdam experience

    NARCIS (Netherlands)

    Kreukels, B.P.C.; Cohen-Kettenis, P.T.

    2011-01-01

    The use of gonadotropin-releasing hormone analogs (GnRHa) to suppress puberty in adolescents with gender dysphoria is a fairly new intervention in the field of gender identity disorders or transsexualism. GnRHa are used to give adolescents time to make balanced decisions on any further treatment

  20. Height suppression of tomato plug seedlings by an environment ...

    African Journals Online (AJOL)

    Experiments were conducted to investigate appropriate concentrations of plant growth retardants (PGRs) and duration of seed soaking in order to suppress hypocotyl length and plug seedling height of 2 tomato cultivars ( Lycopersicum esculentum Mill. cv. Seogeon and Seokwang). Daminozide (B-9), uniconazole ...

  1. Managing Abiotic Factors of Compost to Increase Soilborne Disease Suppression

    Science.gov (United States)

    Griffin, Deirdre E.

    2012-01-01

    Soilborne pathogens can devastate crops, causing economic losses for farmers due to reduced yields and expensive management practices. Fumigants and fungicides have harmful impacts on the surrounding environment and can be toxic to humans. Therefore, alternative methods of disease management are important. The disease suppressive abilities of…

  2. Matairesinol inhibits angiogenesis via suppression of mitochondrial reactive oxygen species

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Boram; Kim, Ki Hyun; Jung, Hye Jin [Chemical Genomics National Research Laboratory, Department of Biotechnology, Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Kwon, Ho Jeong, E-mail: kwonhj@yonsei.ac.kr [Chemical Genomics National Research Laboratory, Department of Biotechnology, Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2012-04-27

    Highlights: Black-Right-Pointing-Pointer Matairesinol suppresses mitochondrial ROS generation during hypoxia. Black-Right-Pointing-Pointer Matairesinol exhibits potent anti-angiogenic activity both in vitro and in vivo. Black-Right-Pointing-Pointer Matairesinol could be a basis for the development of novel anti-angiogenic agents. -- Abstract: Mitochondrial reactive oxygen species (mROS) are involved in cancer initiation and progression and function as signaling molecules in many aspects of hypoxia and growth factor-mediated signaling. Here we report that matairesinol, a natural small molecule identified from the cell-based screening of 200 natural plants, suppresses mROS generation resulting in anti-angiogenic activity. A non-toxic concentration of matairesinol inhibited the proliferation of human umbilical vein endothelial cells. The compound also suppressed in vitro angiogenesis of tube formation and chemoinvasion, as well as in vivo angiogenesis of the chorioallantoic membrane at non-toxic doses. Furthermore, matairesinol decreased hypoxia-inducible factor-1{alpha} in hypoxic HeLa cells. These results demonstrate that matairesinol could function as a novel angiogenesis inhibitor by suppressing mROS signaling.

  3. Fast, fat-suppressed diagnostic imaging of the breast

    International Nuclear Information System (INIS)

    Metzger, G.J.; Weatherall, P.

    1999-01-01

    Maximum sensitivity and diagnostic precision of MR imaging of the breast can be achieved only with fat-suppressed diagnostic scans with high resolution. Optimal results were obtained with a 3D-FFE sequence and excitation by a binomial pulse and an amplitude-modulated binomial pulse. (orig./CB) [de

  4. Feedback control for magnetic island suppression in tokamaks

    NARCIS (Netherlands)

    Hennen, B.A.

    2011-01-01

    A real-time feedback control system has been developed that finds, tracks, suppresses and/or stabilizes resistive magnetic instabilities in a nuclear fusion plasma. In a tokamak, magnetic fields confine a fusion plasma in a topology of toroidally nested magnetic surfaces. The power produced by the

  5. Eye contact facilitates awareness of faces during interocular suppression

    NARCIS (Netherlands)

    Stein, T.; Senju, A.; Peelen, M.V.; Sterzer, P.

    Eye contact captures attention and receives prioritized visual processing. Here we asked whether eye contact might be processed outside conscious awareness. Faces with direct and averted gaze were rendered invisible using interocular suppression. In two experiments we found that faces with direct

  6. Suppression of the two-neutrino double β decay

    International Nuclear Information System (INIS)

    Civitarese, O.; Faessler, A.; Tomoda, T.

    1988-01-01

    Two-neutrino ββ decay rates of 76 Ge, 82 Se, 128,130 Te are calculated in the quasi-particle random phase approximation using a realistic effective NN interaction. The decays are strongly suppressed, in agreement with the experimental data, when a reasonable amount of particle-particle interaction is taken into account. (orig.)

  7. HIV Care Saves Lives: Viral Suppression is Key PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    This 60 second Public Service Announcement is based on the December 2014 Vital Signs. For people living with HIV, Viral suppression is critical. By getting tested and taking HIV medicines, individuals living with HIV can achieve very low levels of HIV in the body.

  8. Interocular suppression in amblyopia for global orientation processing.

    Science.gov (United States)

    Zhou, Jiawei; Huang, Pi-Chun; Hess, Robert F

    2013-04-22

    We developed a dichoptic global orientation coherence paradigm to quantify interocular suppression in amblyopia. This task is biased towards ventral processing and allows comparison with two other techniques-global motion processing, which is more dorsally biased, and binocular phase combination, which most likely reflects striate function. We found a similar pattern for the relationship between coherence threshold and interocular contrast curves (thresholds vs. interocular contrast ratios or TvRs) in our new paradigm compared with those of the previous dichoptic global motion coherence paradigm. The effective contrast ratios at balance point (where the signals from the two eyes have equal weighting) in our new paradigm were larger than those of the dichoptic global motion coherence paradigm but less than those of the binocular phase combination paradigm. The measured effective contrast ratios in the three paradigms were also positively correlated with each other, with the two global coherence paradigms having the highest correlation. We concluded that: (a) The dichoptic global orientation coherence paradigm is effective in quantifying interocular suppression in amblyopia; and (b) Interocular suppression, while sharing a common suppression mechanism at the early stage in the pathway (e.g., striate cortex), may have additional extra-striate contributions that affect both dorsal and ventral streams differentially.

  9. A weed suppressive index for spring barley (Hordeum vulgare) varieties

    DEFF Research Database (Denmark)

    Hansen, P K; Kristensen, K; Willas, J

    2008-01-01

    A screening programme for crop variety competitiveness would ideally be based on only a few, non-destructive measurements of key growth traits. In this study we measured the weed suppressive ability of 79 varieties of spring barley in two ways: (i) directly, by weed coverage assessments under wee...

  10. Fission-suppressed hybrid reactor: the fusion breeder

    International Nuclear Information System (INIS)

    Moir, R.W.; Lee, J.D.; Coops, M.S.

    1982-12-01

    Results of a conceptual design study of a 233 U-producing fusion breeder are presented. The majority of the study was devoted to conceptual design and evaluation of a fission-suppressed blanket and to fuel cycle issues such as fuel reprocessing, fuel handling, and fuel management. Studies in the areas of fusion engineering, reactor safety, and economics were also performed

  11. Suppression device for the reactor water level lowering

    International Nuclear Information System (INIS)

    Kasuga, Hajime; Kasuga, Hiroshi.

    1984-01-01

    Purpose: To suppress the lowering in the reactor water level so as to avoid unnecessary actuation of ECCS upon generation of transient changes which forecasts the lowering of the reactor water level in a BWR type reactor. Constitution: There are provided a water level suppression signal generator for generating a water level suppression signal upon generation of a transient change signal which forecasts the water level lowering in a nuclear reactor and a recycling flow rate controller that applies a recycling flow rate control signal to a recycling pump drive motor by the water level lowering suppression signal. The velocity of the recycling pump is controlled by a reactor scram signal by way of the water level lowering suppresion signal generator and a recycling flow rate controller. Then, the recycling reactor core flow rate is decreased and the void amount in the reactor is transiently increased where the water level tends to increase. Accordingly, the water level lowering by the scram is moderated by the increasing tendency of the water level. (Ikeda, J.)

  12. On the suppression of chaos in quantum and classical physics

    International Nuclear Information System (INIS)

    Fried, H.M.; Gabellini, Y.

    1997-01-01

    A brief outline is presented of an example of potential-theory quantum chaos, which is suppressed by the full radiative corrections of quantum field theory. A similar mechanism may be devised and applied to classically chaotic systems, and provides an example in which an explicit diminution of the original chaos becomes apparent. (author)

  13. SUPPRESSION OF DIELECTRONIC RECOMBINATION DUE TO FINITE DENSITY EFFECTS

    International Nuclear Information System (INIS)

    Nikolić, D.; Gorczyca, T. W.; Korista, K. T.; Ferland, G. J.; Badnell, N. R.

    2013-01-01

    We have developed a general model for determining density-dependent effective dielectronic recombination (DR) rate coefficients in order to explore finite-density effects on the ionization balance of plasmas. Our model consists of multiplying by a suppression factor those highly-accurate total zero-density DR rate coefficients which have been produced from state-of-the-art theoretical calculations and which have been benchmarked by experiment. The suppression factor is based upon earlier detailed collision-radiative calculations which were made for a wide range of ions at various densities and temperatures, but used a simplified treatment of DR. A general suppression formula is then developed as a function of isoelectronic sequence, charge, density, and temperature. These density-dependent effective DR rate coefficients are then used in the plasma simulation code Cloudy to compute ionization balance curves for both collisionally ionized and photoionized plasmas at very low (n e = 1 cm –3 ) and finite (n e = 10 10 cm –3 ) densities. We find that the denser case is significantly more ionized due to suppression of DR, warranting further studies of density effects on DR by detailed collisional-radiative calculations which utilize state-of-the-art partial DR rate coefficients. This is expected to impact the predictions of the ionization balance in denser cosmic gases such as those found in nova and supernova shells, accretion disks, and the broad emission line regions in active galactic nuclei.

  14. Contralateral Suppression of DPOAEs in Mice after Ouabain Treatment

    Directory of Open Access Journals (Sweden)

    Jieying Li

    2018-01-01

    Full Text Available Medial olivocochlear (MOC efferent feedback is suggested to protect the ear from acoustic injury and to increase its ability to discriminate sounds against a noisy background. We investigated whether type II spiral ganglion neurons participate in the contralateral suppression of the MOC reflex. The application of ouabain to the round window of the mouse cochlea selectively induced the apoptosis of the type I spiral ganglion neurons, left the peripherin-immunopositive type II spiral ganglion neurons intact, and did not affect outer hairs, as evidenced by the maintenance of the distorted product otoacoustic emissions (DPOAEs. With the ouabain treatment, the threshold of the auditory brainstem response increased significantly and the amplitude of wave I decreased significantly in the ouabain-treated ears, consistent with the loss of type I neurons. Contralateral suppression was measured as reduction in the amplitude of the 2f1−f2 DPOAEs when noise was presented to the opposite ear. Despite the loss of all the type I spiral ganglion neurons, virtually, the amplitude of the contralateral suppression was not significantly different from the control when the suppressor noise was delivered to the treated cochlea. These results are consistent with the type II spiral ganglion neurons providing the sensory input driving contralateral suppression of the MOC reflex.

  15. Gamma-spectrometry with Compton suppressed detectors arrays

    International Nuclear Information System (INIS)

    Schueck, C.; Hannachi, F.; Chapman, R.

    1985-01-01

    Recent results of experiments performed with two different Compton-suppressed detectors arrays in Daresbury and Berkeley (/sup 163,164/Yb and 154 Er, respectively), are presented together with a brief description of the national French array presently under construction in Strasbourg. 25 refs., 15 figs

  16. Oligotrophic bacteria and root disease suppression in organically managed soils

    NARCIS (Netherlands)

    Senechkin, I.V.

    2013-01-01

    The objective of this thesis was to obtain a better understanding of soil health in terms of microbial and chemical characteristics as well as suppression of soil borne plant pathogens. Organic soils were chosen as an appropriate model for studying soil health. Four different organic

  17. Malaria in immuno-suppressed individuals on antiretroviral therapy ...

    African Journals Online (AJOL)

    Malaria in immuno-suppressed individuals on antiretroviral therapy (ART) in north-central Nigeria. C.R. Pam, B.T. Abubakar, G.O. Inwang, G.A. Amuga. Abstract. The immune deficiency caused by HIV infection reduces the immune response to malaria parasitaemia and therefore leads to an increased frequency of clinical ...

  18. Antisense-induced suppression of taxoid 14β- hydroxylase gene ...

    African Journals Online (AJOL)

    Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that the 14OH mRNA level in transgenic cells dropped dramatically, suggesting that the expression of endogenous14OH gene was significantly suppressed by the exogenous as14OH gene. Correspondingly, the total yield of three major C-14 ...

  19. Suppressing non-periodically repeating disturbances in mechanical servo systems

    NARCIS (Netherlands)

    Tousain, R.L.; Boissy, J.C.; Norg, M.L.; Steinbuch, M.; Bosgra, O.H.

    1998-01-01

    Non-periodically repeating (NPR) disturbances are fixed-shape disturbances that occur randomly in time. We can provide a control system with the capability to suppress this type of disturbance by adding in parallel to the input of the nominal feedback controller a learning look-up-table based

  20. Interaction of tinnitus suppression and hearing ability after cochlear implantation.

    Science.gov (United States)

    Wang, Qian; Li, Jia-Nan; Lei, Guan-Xiong; Chen, Dai-Shi; Wang, Wei-Ze; Chen, Ai-Ting; Mong, Meng-Di; Li, Sun; Jiao, Qing-Shan; Yang, Shi-Ming

    2017-10-01

    To study the postoperative impact of cochlear implants (CIs) on tinnitus, as well as the impact of tinnitus on speech recognition with CI switched on. Fifty-two postlingual deafened CI recipients (21 males and 31 females) were assessed using an established Tinnitus Characteristics Questionnaire and Tinnitus Handicap Inventory (THI) before and after cochlear implantation. The tinnitus loudness was investigated when CI was switched on and off in CI recipients with persistent tinnitus. The relation between tinnitus loudness and recipients' satisfaction of cochlear implantation was analyzed by the visual analogue scale (VAS) score. With CI 'OFF', 42 CI recipients experienced tinnitus postimplant ipsilaterally and 44 contralaterally. Tinnitus was totally suppressed ipsilateral to the CI with CI 'ON' in 42.9%, partially suppressed in 42.9%, unchanged in 11.9% and aggravated in 2.4%. Tinnitus was totally suppressed contralaterally with CI 'ON' in 31.8% of CI recipients, partially suppressed in 47.7%, unchanged in 20.5%. Pearson correlation analysis showed that tinnitus loudness and the results of cochlear implant patients satisfaction was negatively correlated (r = .674, p tinnitus. The tinnitus loudness may affect patients' satisfaction with the use of CI.