Sample records for experiments showed increased

  1. Reducing Defensive Responses to Thoughts of Death: Meditation, Mindfulness, and Buddhism.

    PubMed

    Park, Young Chin; Pyszczynski, Tom

    2017-08-24

    Three studies investigated the effects of meditation on responses to reminders of death. Study 1 took a quasi-experimental approach, comparing defensive responses to mortality salience (MS) of South Korean participants with varying levels of experience with Buddhism and meditation. Whereas non-Buddhists without meditation showed the typical increase in worldview defense after mortality salience (MS), this effect was not found among non-Buddhists immediately after an initial meditation experience, nor among lay Buddhists who meditated regularly or Buddhist monks with intensive meditation experience. Study 2, a fully randomized experiment, showed that MS increased worldview defense among South Koreans at a meditation training who were assessed before meditating but not among participants assessed after their first meditation experience. Study 3 showed that whereas American students without prior meditation experience showed increased worldview defense and suppression of death-related thoughts after MS, these effects were eliminated immediately after an initial meditation experience. Death thought accessibility mediated the effect of MS on worldview defense without meditation, but meditation eliminated this mediation. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. Enhanced Auditory Arousal Increases Intake of Less Palatable and Healthier Foods

    PubMed Central

    Privitera, Gregory J.; Diaz, Melissa; Haas, Meagan C.

    2014-01-01

    Two experiments were conducted to test a prediction of the arousal hypothesis that increased arousal will increase intake of less palatable and healthy foods. In both experiments, arousal was manipulated by adjusting the volume of a movie (soft, loud volume) while participants consumed foods. In Experiment 1, participants ate fresh (palatable) or stale (less palatable) popcorn during a 9-minute movie played at a soft or loud volume. Experiment 2 used the same procedures with healthier foods (carrot sticks and apple slices). Partial support for the arousal hypothesis in Experiment 1 showed that participants consumed more stale but not fresh popcorn in the loud (high arousal) versus soft (low arousal) volume group. These findings suggest that low but not high palatable foods are susceptible to manipulations of arousal. Consistent with this interpretation, Experiment 2 showed that high but not low environmental arousal increased intake of the fruits and vegetables, which are typically rated as lower in palatability compared to high fat foods. These results show that high arousal in an eating-typical environment increases intake of less palatable foods, and healthy foods (i.e., fruits and vegetables). Increasing the availability of healthier foods in a loud food environment can have a positive impact on increasing intake of fruits and vegetables in that environment. PMID:24762340

  3. Enhanced auditory arousal increases intake of less palatable and healthier foods.

    PubMed

    Privitera, Gregory J; Diaz, Melissa; Haas, Meagan C

    2014-01-23

    Two experiments were conducted to test a prediction of the arousal hypothesis that increased arousal will increase intake of less palatable and healthy foods. In both experiments, arousal was manipulated by adjusting the volume of a movie (soft, loud volume) while participants consumed foods. In Experiment 1, participants ate fresh (palatable) or stale (less palatable) popcorn during a 9-minute movie played at a soft or loud volume. Experiment 2 used the same procedures with healthier foods (carrot sticks and apple slices). Partial support for the arousal hypothesis in Experiment 1 showed that participants consumed more stale but not fresh popcorn in the loud (high arousal) versus soft (low arousal) volume group. These findings suggest that low but not high palatable foods are susceptible to manipulations of arousal. Consistent with this interpretation, Experiment 2 showed that high but not low environmental arousal increased intake of the fruits and vegetables, which are typically rated as lower in palatability compared to high fat foods. These results show that high arousal in an eating-typical environment increases intake of less palatable foods, and healthy foods (i.e., fruits and vegetables). Increasing the availability of healthier foods in a loud food environment can have a positive impact on increasing intake of fruits and vegetables in that environment.

  4. Variation of bar-press duration: where do new responses come from?

    PubMed

    Roberts, Seth; Gharib, Afshin

    2006-06-01

    Instrumental learning involves both variation and selection: variation of what the animal does, and selection by reward from among the variation. Four experiments with rats suggested a rule about how variation is controlled by recent events. Experiment 1 used the peak procedure. Measurements of bar-press durations showed a sharp increase in mean duration after the time that food was sometimes given. The increase was triggered by the omission of expected food. Our first explanation of the increase was that it was a frustration effect. Experiment 2 tested this explanation with a procedure in which the first response of a trial usually produced food, ending the trial. In Experiment 2, unlike Experiment 1, omission of expected food did not produce a large increase in bar-press duration, which cast doubt on the frustration explanation. Experiments 3 and 4 tested an alternative explanation: a decrease in expectation of reward increases variation. Both used two signals associated with different probabilities of reward. Bar presses were more variable in duration during the signal with the lower probability of reward, supporting this alternative. These experiments show how variation can be studied with ordinary equipment and responses.

  5. Social stress in early adolescents' daily lives: Associations with affect and loneliness.

    PubMed

    van Roekel, Eeske; Ha, Thao; Verhagen, Maaike; Kuntsche, Emmanuel; Scholte, Ron H J; Engels, Rutger C M E

    2015-12-01

    Adolescence is characterized by increased social stress due to changes in interpersonal relationships, but little is known about daily experiences of social stress. The aim of the present study was to examine daily life predictors of increases in social stress, how these increases affected adolescents' mood, and whether loneliness moderated these relations. The Experience Sampling Method was used to measure positive and negative affect and increases in social stress in 278 early adolescents from the Netherlands. Results showed that adolescents were most likely to experience increases in social stress when they were with classmates, during week days, and in the morning. Lonely adolescents showed higher increases in social stress and responded more negatively to increases in social stress, compared to non-lonely adolescents. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  6. How performance-contingent reward prospect modulates cognitive control: Increased cue maintenance at the cost of decreased flexibility.

    PubMed

    Hefer, Carmen; Dreisbach, Gesine

    2017-10-01

    Growing evidence suggests that reward prospect promotes cognitive stability in terms of increased context or cue maintenance. In 3 Experiments, using different versions of the AX-continuous performance task, we investigated whether this reward effect comes at the cost of decreased cognitive flexibility. Experiment 1 shows that the reward induced increase of cue maintenance perseverates even when reward is no longer available. Experiment 2 shows that this reward effect not only survives the withdrawal of reward but also delays the adaptation to changed task conditions that make cue usage maladaptive. And finally in Experiment 3, it is shown that this reduced flexibility to adapt is observed in a more demanding modified version of the AX-continuous performance task and is even stronger under conditions of sustained reward. Taken together, all 3 Experiments thus speak to the idea that the prospect of reward increases cue maintenance and thereby cognitive stability. This increased cognitive stability however comes at the cost of decreased flexibility in terms of delayed adaptation to new reward and task conditions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Striking the right chord: moving music increases psychological transportation and behavioral intentions.

    PubMed

    Strick, Madelijn; de Bruin, Hanka L; de Ruiter, Linde C; Jonkers, Wouter

    2015-03-01

    Three experiments among university students (N = 372) investigated the persuasive power of moving (i.e., intensely emotional and "chills"-evoking) music in audio-visual advertising. Although advertisers typically aim to increase elaborate processing of the message, these studies illustrate that the persuasive effect of moving music is based on increased narrative transportation ("getting lost" in the ad's story), which reduces critical processing. In Experiment 1, moving music increased transportation and some behavioral intentions (e.g., to donate money). Experiment 2 experimentally increased the salience of manipulative intent of the advertiser, and showed that moving music reduces inferences of manipulative intent, leading in turn to increased behavioral intentions. Experiment 3 tested boundary effects, and showed that moving music fails to increase behavioral intentions when the salience of manipulative intent is either extremely high (which precludes transportation) or extremely low (which precludes reduction of inferences of manipulative intent). Moving music did not increase memory performance, beliefs, and explicit attitudes, suggesting that the influence is affect-based rather cognition-based. Together, these studies illustrate that moving music reduces inferences of manipulation and increases behavioral intentions by transporting viewers into the story of the ad. PsycINFO Database Record (c) 2015 APA, all rights reserved.

  8. Risk attitude in small timesaving decisions.

    PubMed

    Munichor, Nira; Erev, Ido; Lotem, Arnon

    2006-09-01

    Four experiments are presented that explore situations in which a decision maker has to rely on personal experience in an attempt to minimize delays. Experiment 1 shows that risk-attitude in these timesaving decisions is similar to risk-attitude in money-related decisions from experience: A risky prospect is more attractive than a safer prospect with the same expected value only when it leads to a better outcome most of the time. Experiment 2 highlights a boundary condition: It suggests that a difficulty in ranking the relevant delays moves behavior toward random choice. Experiments 3 and 4 show that when actions must be taken during the delay (thereby helping compare delays), this increases the similarity of timesaving decisions to money-related decisions. In these settings the results reflect an increase in risk aversion with experience. The relationship of the results to the study of non-human time-related decisions, human money-related decisions and human time perception is discussed.

  9. A sense of embodiment is reflected in people's signature size.

    PubMed

    Rawal, Adhip; Harmer, Catherine J; Park, Rebecca J; O'Sullivan, Ursula D; Williams, J Mark G

    2014-01-01

    The size of a person's signature may reveal implicit information about how the self is perceived although this has not been closely examined. We conducted three experiments to test whether increases in signature size can be induced. Specifically, the aim of these experiments was to test whether changes in signature size reflect a person's current implicit sense of embodiment. Experiment 1 showed that an implicit affect task (positive subliminal evaluative conditioning) led to increases in signature size relative to an affectively neutral task, showing that implicit affective cues alter signature size. Experiments 2 and 3 demonstrated increases in signature size following experiential self-focus on sensory and affective stimuli relative to both conceptual self-focus and external (non-self-focus) in both healthy participants and patients with anorexia nervosa, a disorder associated with self-evaluation and a sense of disembodiment. In all three experiments, increases in signature size were unrelated to changes in self-reported mood and larger than manipulation unrelated variations. Together, these findings suggest that a person's sense of embodiment is reflected in their signature size.

  10. A Sense of Embodiment Is Reflected in People's Signature Size

    PubMed Central

    Rawal, Adhip; Harmer, Catherine J.; Park, Rebecca J.; O'Sullivan, Ursula D.; Williams, J. Mark G.

    2014-01-01

    Background The size of a person's signature may reveal implicit information about how the self is perceived although this has not been closely examined. Methods/Results We conducted three experiments to test whether increases in signature size can be induced. Specifically, the aim of these experiments was to test whether changes in signature size reflect a person's current implicit sense of embodiment. Experiment 1 showed that an implicit affect task (positive subliminal evaluative conditioning) led to increases in signature size relative to an affectively neutral task, showing that implicit affective cues alter signature size. Experiments 2 and 3 demonstrated increases in signature size following experiential self-focus on sensory and affective stimuli relative to both conceptual self-focus and external (non-self-focus) in both healthy participants and patients with anorexia nervosa, a disorder associated with self-evaluation and a sense of disembodiment. In all three experiments, increases in signature size were unrelated to changes in self-reported mood and larger than manipulation unrelated variations. Conclusions Together, these findings suggest that a person's sense of embodiment is reflected in their signature size. PMID:24533088

  11. Peer effects in unethical behavior: standing or reputation?

    PubMed

    Pascual-Ezama, David; Dunfield, Derek; Gil-Gómez de Liaño, Beatriz; Prelec, Drazen

    2015-01-01

    Recent empirical evidence shows that working in an unsupervised, isolated situation under competition, can increase dishonest behavior to achieve prestige. However, could working in a common space, in the presence of colleagues affect cheating? Here, we examine how familiar-peer influence, supervision and social incentives affect worker performance and dishonest behavior. First, we show that working in the presence of peers is an effective mechanism to constrain honest/dishonest behavior compared to an isolated work situation (experiment 1). Second, we demonstrate that the mere suspicion of dishonesty from another peer is not enough to affect individual cheating behavior (experiment 2), suggesting that reputation holds great importance in a worker's self-image acting as a strong social incentives. Third, we show that when the suspicion of dishonesty increases with multiple peers behaving dishonestly, the desire to increase standing is sufficient to nudge individuals' behavior back to cheating at the same levels as isolated situations (experiment 3).

  12. Peer Effects in Unethical Behavior: Standing or Reputation?

    PubMed Central

    2015-01-01

    Recent empirical evidence shows that working in an unsupervised, isolated situation under competition, can increase dishonest behavior to achieve prestige. However, could working in a common space, in the presence of colleagues affect cheating? Here, we examine how familiar-peer influence, supervision and social incentives affect worker performance and dishonest behavior. First, we show that working in the presence of peers is an effective mechanism to constrain honest/dishonest behavior compared to an isolated work situation (experiment 1). Second, we demonstrate that the mere suspicion of dishonesty from another peer is not enough to affect individual cheating behavior (experiment 2), suggesting that reputation holds great importance in a worker’s self-image acting as a strong social incentives. Third, we show that when the suspicion of dishonesty increases with multiple peers behaving dishonestly, the desire to increase standing is sufficient to nudge individuals’ behavior back to cheating at the same levels as isolated situations (experiment 3). PMID:25853716

  13. Public judgment on science expenditure in the national budget of Japan: An experimental approach to examining the effects of unpacking science.

    PubMed

    Yokoyama, Hiromi M; Nakayachi, Kazuya

    2014-07-01

    How does the public assess an appropriate financial allocation to science promotion? This article empirically examined the subadditivity effect in the judgment of budgetary allocation. Results of the first experiment showed that the ratio of the national budget allocated for science promotion by participants increased when science was decomposed into more specific categories compared to when it was presented as "science promotion" alone. Consistent with these findings, results of the second experiment showed that the allotment ratio to science promotion decreased when the number of other expenditure items increased. Meanwhile, the third experiment revealed that in the case of a budgetary cutback, the total amount taken from science promotion greatly increased when science was decomposed into subcategories. The subadditivity effect and increase in the total allotment ratio by unpacking science promotion was confirmed by these three experiments not only on budgetary allocation but also on budgetary cutback.

  14. Mindfulness meditation and relaxation training increases time sensitivity.

    PubMed

    Droit-Volet, S; Fanget, M; Dambrun, M

    2015-01-01

    Two experiments examined the effect of mindfulness meditation and relaxation on time perception using a temporal bisection task. In Experiment 1, the participants performed a temporal task before and after exercises of mindfulness meditation or relaxation. In Experiment 2, the procedure was similar than that used in Experiment 1, except that the participants were trained to mediate or relax every day over a period of several weeks. The results showed that mindfulness meditation exercises increased sensitivity to time and lengthened perceived time. However, this temporal improvement with meditation exercises was primarily observed in the experienced meditators. Our results also showed the experienced meditators were less anxious than the novice participants, and that the sensitivity to time increased when the level of anxiety decreased. Our results were explained by the practice of mindfulness technique that had developed individuals' abilities in devoting more attention resources to temporal information processing. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Immediate and subsequent effects of matched and unmatched stimuli on targeted vocal stereotypy and untargeted motor stereotypy.

    PubMed

    Rapp, John T; Swanson, Greg; Sheridan, Stephanie M; Enloe, Kimberly A; Maltese, Diana; Sennott, Lisa A; Shrader, Lauren; Carroll, Regina A; Richling, Sarah M; Long, Ethan S; Lanovaz, Marc J

    2013-07-01

    The authors evaluated the effects of matched and unmatched stimuli on immediate and subsequent engagement in targeted vocal stereotypy (Experiment 1) and untargeted motor stereotypy (Experiment 2). Results of Experiment 1 showed that (a) matched stimulation decreased immediate engagement in vocal stereotypy for 8 of 11 participants and increased subsequent engagement in vocal stereotypy for only 1 of the 8 participants and (b) unmatched stimulation decreased immediate engagement in vocal stereotypy for only 1 of 10 participants and did not increase subsequent engagement in vocal stereotypy for this participant. Results of Experiment 2 showed that for 8 of 14 participants, untargeted stereotypy increased when the matched or unmatched stimulus was present, after it was removed, or both. The authors briefly discuss the potential clinical implications of using matched stimulation to decrease vocal stereotypy and limitations of the findings.

  16. Crossing the Hands Increases Illusory Self-Touch

    PubMed Central

    Pozeg, Polona; Rognini, Giulio; Salomon, Roy; Blanke, Olaf

    2014-01-01

    Manipulation of hand posture, such as crossing the hands, has been frequently used to study how the body and its immediately surrounding space are represented in the brain. Abundant data show that crossed arms posture impairs remapping of tactile stimuli from somatotopic to external space reference frame and deteriorates performance on several tactile processing tasks. Here we investigated how impaired tactile remapping affects the illusory self-touch, induced by the non-visual variant of the rubber hand illusion (RHI) paradigm. In this paradigm blindfolded participants (Experiment 1) had their hands either uncrossed or crossed over the body midline. The strength of illusory self-touch was measured with questionnaire ratings and proprioceptive drift. Our results showed that, during synchronous tactile stimulation, the strength of illusory self-touch increased when hands were crossed compared to the uncrossed posture. Follow-up experiments showed that the increase in illusion strength was not related to unfamiliar hand position (Experiment 2) and that it was equally strengthened regardless of where in the peripersonal space the hands were crossed (Experiment 3). However, while the boosting effect of crossing the hands was evident from subjective ratings, the proprioceptive drift was not modulated by crossed posture. Finally, in contrast to the illusion increase in the non-visual RHI, the crossed hand postures did not alter illusory ownership or proprioceptive drift in the classical, visuo-tactile version of RHI (Experiment 4). We argue that the increase in illusory self-touch is related to misalignment of somatotopic and external reference frames and consequently inadequate tactile-proprioceptive integration, leading to re-weighting of the tactile and proprioceptive signals.The present study not only shows that illusory self-touch can be induced by crossing the hands, but importantly, that this posture is associated with a stronger illusion. PMID:24699795

  17. Abscisic Acid Regulation of Root Hydraulic Conductivity and Aquaporin Gene Expression Is Crucial to the Plant Shoot Growth Enhancement Caused by Rhizosphere Humic Acids.

    PubMed

    Olaetxea, Maite; Mora, Verónica; Bacaicoa, Eva; Garnica, María; Fuentes, Marta; Casanova, Esther; Zamarreño, Angel M; Iriarte, Juan C; Etayo, David; Ederra, Iñigo; Gonzalo, Ramón; Baigorri, Roberto; García-Mina, Jose M

    2015-12-01

    The physiological and metabolic mechanisms behind the humic acid-mediated plant growth enhancement are discussed in detail. Experiments using cucumber (Cucumis sativus) plants show that the shoot growth enhancement caused by a structurally well-characterized humic acid with sedimentary origin is functionally associated with significant increases in abscisic acid (ABA) root concentration and root hydraulic conductivity. Complementary experiments involving a blocking agent of cell wall pores and water root transport (polyethylenglycol) show that increases in root hydraulic conductivity are essential in the shoot growth-promoting action of the model humic acid. Further experiments involving an inhibitor of ABA biosynthesis in root and shoot (fluridone) show that the humic acid-mediated enhancement of both root hydraulic conductivity and shoot growth depended on ABA signaling pathways. These experiments also show that a significant increase in the gene expression of the main root plasma membrane aquaporins is associated with the increase of root hydraulic conductivity caused by the model humic acid. Finally, experimental data suggest that all of these actions of model humic acid on root functionality, which are linked to its beneficial action on plant shoot growth, are likely related to the conformational structure of humic acid in solution and its interaction with the cell wall at the root surface. © 2015 American Society of Plant Biologists. All Rights Reserved.

  18. Abscisic Acid Regulation of Root Hydraulic Conductivity and Aquaporin Gene Expression Is Crucial to the Plant Shoot Growth Enhancement Caused by Rhizosphere Humic Acids1

    PubMed Central

    Bacaicoa, Eva; Garnica, María; Fuentes, Marta; Casanova, Esther; Etayo, David; Ederra, Iñigo; Gonzalo, Ramón

    2015-01-01

    The physiological and metabolic mechanisms behind the humic acid-mediated plant growth enhancement are discussed in detail. Experiments using cucumber (Cucumis sativus) plants show that the shoot growth enhancement caused by a structurally well-characterized humic acid with sedimentary origin is functionally associated with significant increases in abscisic acid (ABA) root concentration and root hydraulic conductivity. Complementary experiments involving a blocking agent of cell wall pores and water root transport (polyethylenglycol) show that increases in root hydraulic conductivity are essential in the shoot growth-promoting action of the model humic acid. Further experiments involving an inhibitor of ABA biosynthesis in root and shoot (fluridone) show that the humic acid-mediated enhancement of both root hydraulic conductivity and shoot growth depended on ABA signaling pathways. These experiments also show that a significant increase in the gene expression of the main root plasma membrane aquaporins is associated with the increase of root hydraulic conductivity caused by the model humic acid. Finally, experimental data suggest that all of these actions of model humic acid on root functionality, which are linked to its beneficial action on plant shoot growth, are likely related to the conformational structure of humic acid in solution and its interaction with the cell wall at the root surface. PMID:26450705

  19. Day-to-day mastery and self-efficacy changes during a smoking quit attempt: Two studies.

    PubMed

    Warner, Lisa M; Stadler, Gertraud; Lüscher, Janina; Knoll, Nina; Ochsner, Sibylle; Hornung, Rainer; Scholz, Urte

    2018-05-01

    In social-cognitive theory, it is hypothesized that mastery experiences (successfully implementing behaviour change) are a source of self-efficacy, and self-efficacy increases the opportunity for experiencing mastery. Vicarious experiences (seeing others succeed) are suggested as another source of self-efficacy. However, the hypothesis of this reciprocal relationship has not been tested using a day-to-day design. This article reports findings from two intensive longitudinal studies, testing the reciprocal relationship of self-efficacy and its two main sources within the naturally occurring process of quitting smoking (without intervention). Smokers (Study 1: N = 100 smokers in smoker-non-smoker couples (1,787 observations); Study 2; N = 81 female (1,401 observations) and N = 79 male smokers (1,328 observations) in dual-smoker couples) reported their mastery experiences (not smoking the entire day; in Study 2, mastery experience of partner served as vicarious experience) and smoking-specific self-efficacy for 21 days after a self-set quit date. Time-lagged multilevel analyses were conducted using change-predicting-change models. Increases in mastery experiences predicted changes in self-efficacy, and increases in self-efficacy predicted changes in mastery experiences in Study 1. Study 2 replicated these results and showed contagion effects (partners' mastery on individuals' mastery and partners' self-efficacy on individuals' self-efficacy), but found no evidence for a link between vicarious experiences (partners' mastery experiences) and individuals' self-efficacy. This article demonstrates that mastery experiences and self-efficacy show a reciprocal relationship within smokers during a quit attempt in a day-to-day design, as well as contagion effects in couples when both partners try to quit simultaneously. Statement of Contribution What is already known on this subject? Self-efficacy is one of the strongest correlates of quitting smoking. Despite the assumptions on how self-efficacy is built formulated by Bandura two decades ago, there is only little empirical evidence on the origins of self-efficacy. The open research questions for these two studies were whether mastery experiences (experiencing success with the new behavior) and vicarious experiences (seeing others succeed) facilitate the smoking cessation process, whether mastery experiences and self-efficacy affect one another reciprocally and whether intimate partners serve as role models for each other. What does this study add? Mastery experiences and self-efficacy are mutually depended on a day-to-day basis within the smoking cessation process. Effects of mastery experiences fade rapidly, indicating that constant successes are needed to keep up self-efficacy. Dual-smoker couples show similar changes in a contagious way - if mastery experiences increase in one person, mastery experiences increase in the partner; if self-efficacy increases in one person, self-efficacy increases in the partner, too. No support for vicarious experiences (mastery experiences in one person affecting self-efficacy in the partner and vice versa) as sources of self-efficacy in the quitting process was found. © 2018 The British Psychological Society.

  20. Inhibitory competition in figure-ground perception: context and convexity.

    PubMed

    Peterson, Mary A; Salvagio, Elizabeth

    2008-12-15

    Convexity has long been considered a potent cue as to which of two regions on opposite sides of an edge is the shaped figure. Experiment 1 shows that for a single edge, there is only a weak bias toward seeing the figure on the convex side. Experiments 1-3 show that the bias toward seeing the convex side as figure increases as the number of edges delimiting alternating convex and concave regions increases, provided that the concave regions are homogeneous in color. The results of Experiments 2 and 3 rule out a probability summation explanation for these context effects. Taken together, the results of Experiments 1-3 show that the homogeneity versus heterogeneity of the convex regions is irrelevant. Experiment 4 shows that homogeneity of alternating regions is not sufficient for context effects; a cue that favors the perception of the intervening regions as figures is necessary. Thus homogeneity alone does not alone operate as a background cue. We interpret our results within a model of figure-ground perception in which shape properties on opposite sides of an edge compete for representation and the competitive strength of weak competitors is further reduced when they are homogeneous.

  1. Psychophysiological effects of self-regulation method: EEG frequency analysis and contingent negative variations.

    PubMed

    Ikemi, A

    1988-01-01

    Experiments were conducted to investigate the psychophysiological effects of self-regulation method (SRM), a newly developed method of self-control, using EEG frequency analysis and contingent negative variations (CNV). The results of the EEG frequency analysis showed that there is a significant increase in the percentage (power) of the theta-band and a significant decrease in the percentage (power) of the beta-band during SRM. Moreover, the results of an identical experiment conducted on subjects in a drowsy state showed that the changes in EEG frequencies during SRM can be differentiated from those of a drowsy state. Furthermore, experiments using CNV showed that there is a significant reduction of CNV amplitude during SRM. Despite the reduced amplitude during SRM, the number of errors in a task to evoke the CNV was reduced significantly without significant delay of reaction time. When an identical experiment was conducted in a drowsy state, CNV amplitude was reduced significantly, but reaction time and errors increased. From these experiments, the state of vigilance during SRM was discussed as a state of 'relaxed alertness'.

  2. Studies on penetration of antibiotic in bacterial cells in space conditions (7-IML-1)

    NASA Technical Reports Server (NTRS)

    Tixador, R.

    1992-01-01

    The Cytos 2 experiment was performed aboard Salyut 7 in order to test the antibiotic sensitivity of bacteria cultivated in vitro in space. An increase of the Minimal Inhibitory Concentration (MIC) in the inflight cultures (i.e., an increase of the antibiotic resistance) was observed. Complementary studies of the ultrastructure showed a thickening of the cell envelope. In order to confirm the results of the Cytos 2 experiment, we performed the ANTIBIO experiment during the D1 mission to try to differentiate, by means of the 1 g centrifuge in the Biorack, between the biological effects of cosmic rays and those caused by microgravity conditions. The originality of this experiment was in the fact that it was designed to test the antibiotic sensitivity of bacteria cultivated in vitro during the orbital phase of the flight. The results show an increase in resistance to Colistin in in-flight bacteria. The MIC is practically double in the in-flight cultures. A cell count of living bacteria in the cultures containing the different Colistin concentrations showed a significant difference between the cultures developed during space flight and the ground based cultures. The comparison between the 1 g and 0 g in-flight cultures show similar behavior for the two sets. Nevertheless, a small difference between the two sets of ground based control cultures was noted. The cultures developed on the ground centrifuge (1.4 g) present a slight decrease in comparison with the cultures developed in the static rack (1 g). In order to approach the mechanisms of the increase of antibiotic resistance on bacteria cultivated in vitro in space, we have proposed the study on penetration of antibiotics in bacterial cells in space conditions. This experiment was selected for the International Microgravity Laboratory 1 (IML-1) mission.

  3. [Allocation of attentional resource and monitoring processes under rapid serial visual presentation].

    PubMed

    Nishiura, K

    1998-08-01

    With the use of rapid serial visual presentation (RSVP), the present study investigated the cause of target intrusion errors and functioning of monitoring processes. Eighteen students participated in Experiment 1, and 24 in Experiment 2. In Experiment 1, different target intrusion errors were found depending on different kinds of letters --romaji, hiragana, and kanji. In Experiment 2, stimulus set size and context information were manipulated in an attempt to explore the cause of post-target intrusion errors. Results showed that as stimulus set size increased, the post-target intrusion errors also increased, but contextual information did not affect the errors. Results concerning mean report probability indicated that increased allocation of attentional resource to response-defining dimension was the cause of the errors. In addition, results concerning confidence rating showed that monitoring of temporal and contextual information was extremely accurate, but it was not so for stimulus information. These results suggest that attentional resource is different from monitoring resource.

  4. Modifying mixing and instability growth through the adjustment of initial conditions in a high-energy-density counter-propagating shear experiment on OMEGA

    DOE PAGES

    Merritt, E. C.; Doss, F. W.; Loomis, E. N.; ...

    2015-06-24

    Counter-propagating shear experiments conducted at the OMEGA Laser Facility have been evaluating the effect of target initial conditions, specifically the characteristics of a tracer foil located at the shear boundary, on Kelvin-Helmholtz instability evolution and experiment transition toward nonlinearity and turbulence in the high-energy-density (HED) regime. Experiments are focused on both identifying and uncoupling the dependence of the model initial turbulent length scale in variable-density turbulence models of k-ϵ type on competing physical instability seed lengths as well as developing a path toward fully developed turbulent HED experiments. We present results from a series of experiments controllably and independently varyingmore » two initial types of scale lengths in the experiment: the thickness and surface roughness (surface perturbation scale spectrum) of a tracer layer at the shear interface. We show that decreasing the layer thickness and increasing the surface roughness both have the ability to increase the relative mixing in the system, and thus theoretically decrease the time required to begin transitioning to turbulence in the system. In addition, we also show that we can connect a change in observed mix width growth due to increased foil surface roughness to an analytically predicted change in model initial turbulent scale lengths.« less

  5. Covariation Neglect among Novice Investors

    ERIC Educational Resources Information Center

    Hedesstrom, Ted Martin; Svedsater, Henrik; Garling, Tommy

    2006-01-01

    In 4 experiments, undergraduates made hypothetical investment choices. In Experiment 1, participants paid more attention to the volatility of individual assets than to the volatility of aggregated portfolios. The results of Experiment 2 show that most participants diversified even when this increased risk because of covariation between the returns…

  6. Processes of Overall Similarity Sorting in Free Classification

    ERIC Educational Resources Information Center

    Milton, Fraser; Longmore, Christopher A.; Wills, A. J.

    2008-01-01

    The processes of overall similarity sorting were investigated in 5 free classification experiments. Experiments 1 and 2 demonstrated that increasing time pressure can reduce the likelihood of overall similarity categorization. Experiment 3 showed that a concurrent load also reduced overall similarity sorting. These findings suggest that overall…

  7. How Performance-Contingent Reward Prospect Modulates Cognitive Control: Increased Cue Maintenance at the Cost of Decreased Flexibility

    ERIC Educational Resources Information Center

    Hefer, Carmen; Dreisbach, Gesine

    2017-01-01

    Growing evidence suggests that reward prospect promotes cognitive stability in terms of increased context or cue maintenance. In 3 Experiments, using different versions of the AX-continuous performance task, we investigated whether this reward effect comes at the cost of decreased cognitive flexibility. Experiment 1 shows that the reward induced…

  8. Emotional arousal enhances word repetition priming

    PubMed Central

    Thomas, Laura A.; LaBar, Kevin S.

    2012-01-01

    Three experiments were conducted to determine if emotional content increases repetition priming magnitude. In the study phase of Experiment 1, participants rated high-arousing negative (taboo) words and neutral words for concreteness. In the test phase, they made lexical decision judgements for the studied words intermixed with novel words (half taboo, half neutral) and pseudowords. In Experiment 2, low-arousing negative (LAN) words were substituted for the taboo words, and in Experiment 3 all three word types were used. Results showed significant priming in all experiments, as indicated by faster reaction times for studied words than for novel words. A priming × emotion interaction was found in Experiments 1 and 3, with greater priming for taboo relative to neutral words. The LAN words in Experiments 2 and 3 showed no difference in priming magnitude relative to the other word types. These results show selective enhancement of word repetition priming by emotional arousal. PMID:26321783

  9. Conditioned [corrected] stimulus informativeness governs conditioned stimulus-unconditioned stimulus associability.

    PubMed

    Ward, Ryan D; Gallistel, C R; Jensen, Greg; Richards, Vanessa L; Fairhurst, Stephen; Balsam, Peter D

    2012-07-01

    In a conditioning protocol, the onset of the conditioned stimulus ([CS]) provides information about when to expect reinforcement (unconditioned stimulus [US]). There are two sources of information from the CS in a delay conditioning paradigm in which the CS-US interval is fixed. The first depends on the informativeness, the degree to which CS onset reduces the average expected time to onset of the next US. The second depends only on how precisely a subject can represent a fixed-duration interval (the temporal Weber fraction). In three experiments with mice, we tested the differential impact of these two sources of information on rate of acquisition of conditioned responding (CS-US associability). In Experiment 1, we showed that associability (the inverse of trials to acquisition) increased in proportion to informativeness. In Experiment 2, we showed that fixing the duration of the US-US interval or the CS-US interval or both had no effect on associability. In Experiment 3, we equated the increase in information produced by varying the C/T ratio with the increase produced by fixing the duration of the CS-US interval. Associability increased with increased informativeness, but, as in Experiment 2, fixing the CS-US duration had no effect on associability. These results are consistent with the view that CS-US associability depends on the increased rate of reward signaled by CS onset. The results also provide further evidence that conditioned responding is temporally controlled when it emerges.

  10. CS Informativeness Governs CS-US Associability

    PubMed Central

    Ward, Ryan D.; Gallistel, C. R.; Jensen, Greg; Richards, Vanessa L.; Fairhurst, Stephen; Balsam, Peter D

    2012-01-01

    In a conditioning protocol, the onset of the conditioned stimulus (CS) provides information about when to expect reinforcement (the US). There are two sources of information from the CS in a delay conditioning paradigm in which the CS-US interval is fixed. The first depends on the informativeness, the degree to which CS onset reduces the average expected time to onset of the next US. The second depends only on how precisely a subject can represent a fixed-duration interval (the temporal Weber fraction). In three experiments with mice, we tested the differential impact of these two sources of information on rate of acquisition of conditioned responding (CS-US associability). In Experiment 1, we show that associability (the inverse of trials to acquisition) increases in proportion to informativeness. In Experiment 2, we show that fixing the duration of the US-US interval or the CS-US interval or both has no effect on associability. In Experiment 3, we equated the increase in information produced by varying the C̅/T̅ ratio with the increase produced by fixing the duration of the CS-US interval. Associability increased with increased informativeness, but, as in Experiment 2, fixing the CS-US duration had no effect on associability. These results are consistent with the view that CS-US associability depends on the increased rate of reward signaled by CS onset. The results also provide further evidence that conditioned responding is temporally controlled when it emerges. PMID:22468633

  11. Thinking in Black and White: Conscious thought increases racially biased judgments through biased face memory.

    PubMed

    Strick, Madelijn; Stoeckart, Peter F; Dijksterhuis, Ap

    2015-11-01

    It is a common research finding that conscious thought helps people to avoid racial discrimination. These three experiments, however, illustrate that conscious thought may increase biased face memory, which leads to increased judgment bias (i.e., preferring White to Black individuals). In Experiments 1 and 2, university students formed impressions of Black and White housemate candidates. They judged the candidates either immediately (immediate decision condition), thought about their judgments for a few minutes (conscious thought condition), or performed an unrelated task for a few minutes (unconscious thought condition). Conscious thinkers and immediate decision-makers showed a stronger face memory bias than unconscious thinkers, and this mediated increased judgment bias, although not all results were significant. Experiment 3 used a new, different paradigm and showed that a Black male was remembered as darker after a period of conscious thought than after a period of unconscious thought. Implications for racial prejudice are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Facilitating interest and out-of-school engagement in science in secondary school girls: Increasing the effectiveness of the teaching for transformative experience in science model through parental involvement

    NASA Astrophysics Data System (ADS)

    Heddy, Benjamin Charles

    This study investigated the impact of adding a parental involvement intervention to the Teaching for Transformative Experience in Science (TTES) model in science courses (biology and chemistry) in an all-girl middle and high school (N = 89). Specifically, the goal was to increase out-of-school engagement, interest, parental involvement, and achievement. Analysis showed that TTES with the addition of a parent intervention (TTES+PI) facilitated more out-of-school engagement and parent involvement than a comparison. Furthermore, a high initial level of situational and individual interest was maintained in the TTES+PI condition; whereas both forms of interest decreased in the comparison. A content analysis of transformative experience journal entries suggested that when parents showed value for science concepts, students' experiential value increased. The results provide evidence that the addition of a parent intervention may increase the effectiveness of TTES and maintain girl's interest in science, which has theoretical and practical implications.

  13. Human Infants' Preference for Left-to-Right Oriented Increasing Numerical Sequences

    PubMed Central

    de Hevia, Maria Dolores; Girelli, Luisa; Addabbo, Margaret; Macchi Cassia, Viola

    2014-01-01

    While associations between number and space, in the form of a spatially oriented numerical representation, have been extensively reported in human adults, the origins of this phenomenon are still poorly understood. The commonly accepted view is that this number-space association is a product of human invention, with accounts proposing that culture, symbolic knowledge, and mathematics education are at the roots of this phenomenon. Here we show that preverbal infants aged 7 months, who lack symbolic knowledge and mathematics education, show a preference for increasing magnitude displayed in a left-to-right spatial orientation. Infants habituated to left-to-right oriented increasing or decreasing numerical sequences showed an overall higher looking time to new left-to-right oriented increasing numerical sequences at test (Experiment 1). This pattern did not hold when infants were presented with the same ordinal numerical information displayed from right to left (Experiment 2). The different pattern of results was congruent with the presence of a malleable, context-dependent baseline preference for increasing, left-to-right oriented, numerosities (Experiment 3). These findings are suggestive of an early predisposition in humans to link numerical order with a left-to-right spatial orientation, which precedes the acquisition of symbolic abilities, mathematics education, and the acquisition of reading and writing skills. PMID:24802083

  14. The use of visual and verbal means of communication across psychological distance.

    PubMed

    Amit, Elinor; Wakslak, Cheryl; Trope, Yaacov

    2013-01-01

    The current study investigated the effect of distance on medium preferences in interpersonal communication. Five experiments showed that people's preference for using pictures (vs. words) is increasingly higher when communicating with temporally, socially, or geographically proximal (vs. distal) others. In contrast, preference for words is increasingly higher when communicating with those who were distal. A sixth experiment showed that communication's medium influences distance preferences, such that people's preference for communicating a message to a distant (vs. proximal) target is greater for verbal compared with pictorial communications. A seventh experiment showed that recipients are more likely to heed a sender's suggestions when the medium and distance are congruent. These findings reflect the suitability of pictures for communication with proximal others and words with distal others. Implications of these findings for construal-level theory, perspective taking, embodied cognition, the development of language, and social skills with children are discussed.

  15. Disgust as Embodied Moral Judgment

    PubMed Central

    Schnall, Simone; Haidt, Jonathan; Clore, Gerald L.; Jordan, Alexander H.

    2008-01-01

    How, and for whom, does disgust influence moral judgment? In 4 experiments participants made moral judgments while experiencing extraneous feelings of disgust. Disgust was induced in Experiment 1 by exposure to a bad smell, in Experiment 2 by working in a disgusting room, in Experiment 3 by recalling a physically disgusting experience, and in Experiment 4 through a video induction. In each case, the results showed that disgust can increase the severity of moral judgments relative to controls. Experiment 4 found that disgust had a different effect on moral judgment than did sadness. In addition, Experiments 2-4 showed that the role of disgust in severity of moral judgments depends on participants’ sensitivity to their own bodily sensations. Taken together, these data indicate the importance - and specificity - of gut feelings in moral judgments. PMID:18505801

  16. How power influences moral thinking.

    PubMed

    Lammers, Joris; Stapel, Diederik A

    2009-08-01

    The authors conducted 5 studies to test the idea that both thinking about and having power affects the way in which people resolve moral dilemmas. It is shown that high power increases the use of rule-based (deontological) moral thinking styles, whereas low power increases reliance on outcome-based (consequentialist) moral thinking. Stated differently, in determining whether an act is right or wrong, the powerful focus on whether rules and principles are violated, whereas the powerless focus on the consequences. For this reason, the powerful are also more inclined to stick to the rules, irrespective of whether this has positive or negative effects, whereas the powerless are more inclined to make exceptions. The first 3 experiments show that thinking about power increases rule-based thinking and decreases outcome-based thinking in participants' moral decision making. A 4th experiment shows the mediating role of moral orientation in the effect of power on moral decisions. The 5th experiment demonstrates the role of self-interest by showing that the power-moral link is reversed when rule-based decisions threaten participants' own self-interests.

  17. Convincing Yourself to Care About Others: An Intervention for Enhancing Benevolence Values.

    PubMed

    Arieli, Sharon; Grant, Adam M; Sagiv, Lilach

    2014-02-01

    To study value change, this research presents an intervention with multiple exercises designed to instigate change through both effortful and automatic routes. Aiming to increase the importance attributed to benevolence values, which reflect the motivation to help and care for others, the intervention combines three mechanisms for value change (self-persuasion, consistency-maintenance, and priming). In three experiments, 142 undergraduates (67% male, ages 19-26) participated in an intervention emphasizing the importance of either helping others (benevolence condition) or recognizing flexibility in personality (control condition). We measured the importance of benevolence values before and after the task. In Experiment 1, the intervention increased U.S. participants' benevolence values. In Experiment 2, we replicated these effects in a different culture (Israel) and also showed that by enhancing benevolence values, the intervention increased participants' willingness to volunteer to help others. Experiment 3 showed that the increases in the importance of benevolence values lasted at least 4 weeks. Our results provide evidence that value change does not require fictitious feedback or information about social norms, but can occur through a 30-min intervention that evokes both effortful and automatic processes. © 2013 Wiley Periodicals, Inc.

  18. Responsibility and the sense of agency enhance empathy for pain

    PubMed Central

    Lepron, Evelyne; Causse, Michaël; Farrer, Chlöé

    2015-01-01

    Being held responsible for our actions strongly determines our moral judgements and decisions. This study examined whether responsibility also influences our affective reaction to others' emotions. We conducted two experiments in order to assess the effect of responsibility and of a sense of agency (the conscious feeling of controlling an action) on the empathic response to pain. In both experiments, participants were presented with video clips showing an actor's facial expression of pain of varying intensity. The empathic response was assessed with behavioural (pain intensity estimation from facial expressions and unpleasantness for the observer ratings) and electrophysiological measures (facial electromyography). Experiment 1 showed enhanced empathic response (increased unpleasantness for the observer and facial electromyography responses) as participants' degree of responsibility for the actor's pain increased. This effect was mainly accounted for by the decisional component of responsibility (compared with the execution component). In addition, experiment 2 found that participants' unpleasantness rating also increased when they had a sense of agency over the pain, while controlling for decision and execution processes. The findings suggest that increased empathy induced by responsibility and a sense of agency may play a role in regulating our moral conduct. PMID:25473014

  19. Perceptual expertise: can sensorimotor experience change holistic processing and left-side bias?

    PubMed

    Tso, Ricky Van-yip; Au, Terry Kit-fong; Hsiao, Janet Hui-wen

    2014-09-01

    Holistic processing and left-side bias are both behavioral markers of expert face recognition. By contrast, expert recognition of characters in Chinese orthography involves left-side bias but reduced holistic processing, although faces and Chinese characters share many visual properties. Here, we examined whether this reduction in holistic processing of Chinese characters can be better explained by writing experience than by reading experience. Compared with Chinese nonreaders, Chinese readers who had limited writing experience showed increased holistic processing, whereas Chinese readers who could write characters fluently showed reduced holistic processing. This result suggests that writing and sensorimotor experience can modulate holistic-processing effects and that the reduced holistic processing observed in expert Chinese readers may depend mostly on writing experience. However, both expert writers and writers with limited experience showed similarly stronger left-side bias than novices did in processing mirror-symmetric Chinese characters; left-side bias may therefore be a robust expertise marker for object recognition that is uninfluenced by sensorimotor experience. © The Author(s) 2014.

  20. A Lenz's law experiment revisited

    NASA Astrophysics Data System (ADS)

    Sawicki, Charles A.

    2000-10-01

    A dipole magnet model predicts a terminal velocity VT proportional to 1/n for n attached identical cylindrical magnets dropped down a copper pipe. Experiments show that VT increases approximately linearly with n. The explanation for this difference is presented.

  1. The Escherichia coli regulator of sigma 70 protein, Rsd, can up-regulate some stress-dependent promoters by sequestering sigma 70.

    PubMed

    Mitchell, Jennie E; Oshima, Taku; Piper, Sarah E; Webster, Christine L; Westblade, Lars F; Karimova, Gouzel; Ladant, Daniel; Kolb, Annie; Hobman, Jon L; Busby, Stephen J W; Lee, David J

    2007-05-01

    The Escherichia coli Rsd protein forms complexes with the RNA polymerase sigma(70) factor, but its biological role is not understood. Transcriptome analysis shows that overexpression of Rsd causes increased expression from some promoters whose expression depends on the alternative sigma(38) factor, and this was confirmed by experiments with lac fusions at selected promoters. The LP18 substitution in Rsd increases the Rsd-dependent stimulation of these promoter-lac fusions. Analysis with a bacterial two-hybrid system shows that the LP18 substitution in Rsd increases its interaction with sigma(70). Our experiments support a model in which the role of Rsd is primarily to sequester sigma(70), thereby increasing the levels of RNA polymerase containing the alternative sigma(38) factor.

  2. The storage capacity of fluorine in olivine and pyroxene under upper mantle conditions

    NASA Astrophysics Data System (ADS)

    Grützner, Tobias; Kohn, Simon C.; Bromiley, David W.; Rohrbach, Arno; Berndt, Jasper; Klemme, Stephan

    2017-07-01

    We present new experimental results on the fluorine storage capacity of olivine and orthopyroxene in the Earth's mantle. Experiments were performed in the system MgO-SiO2 + MgF2 at temperatures between 1350 °C and 1700 °C and pressures up to 17 GPa. Electron microprobe measurements show that fluorine concentrations in olivine reach up to 5100 μg/g. The storage capacity of fluorine in olivine shows only a small pressure dependence but a strong temperature dependence with a positive correlation between increasing temperature and fluorine storage capacity. Fluorine concentrations found in enstatite are one order of magnitude smaller and reach up to 670 μg/g. Our data show that concentrations of fluorine in fluorine-saturated olivine are in the same range as water concentrations in olivine. Nevertheless, fluorine and water solubility in olivine show opposing behavior with increasing pressure and temperature. The fluorine solubility in olivine increases with increasing temperature but is not much affected by pressure. In contrast, water solubility in olivine has previously been shown to decrease with increasing temperature and increase with increasing pressure. Our experiments show that nominally fluorine-free minerals like forsterite and enstatite are capable of storing the entire fluorine budget of the upper mantle, without the need to invoke accessory phases such as apatite or amphibole.

  3. Use of Enzymes in Organic Synthesis: Reduction of Ketones by Baker's Yeast Revisited

    ERIC Educational Resources Information Center

    Patterson, James; Sigurdsson, Snorri Th.

    2005-01-01

    The reduction of ethyl acetoacetate using common baker's yeast is a traditional experiment that shows the stereoselective power of a biochemical system. Addition of organic solvents to aqueous reaction system increased the yields and reproducibility of the experiment thus overcoming the two problems associated with the experiment, low yield, and…

  4. The Martyrdom Effect: When Pain and Effort Increase Prosocial Contributions

    PubMed Central

    Olivola, Christopher Y; Shafir, Eldar

    2013-01-01

    Most theories of motivation and behavior (and lay intuitions alike) consider pain and effort to be deterrents. In contrast to this widely held view, we provide evidence that the prospect of enduring pain and exerting effort for a prosocial cause can promote contributions to the cause. Specifically, we show that willingness to contribute to a charitable or collective cause increases when the contribution process is expected to be painful and effortful rather than easy and enjoyable. Across five experiments, we document this “martyrdom effect,” show that the observed patterns defy standard economic and psychological accounts, and identify a mediator and moderator of the effect. Experiment 1 showed that people are willing to donate more to charity when they anticipate having to suffer to raise money. Experiment 2 extended these findings to a non-charity laboratory context that involved real money and actual pain. Experiment 3 demonstrated that the martyrdom effect is not the result of an attribute substitution strategy (whereby people use the amount of pain and effort involved in fundraising to determine donation worthiness). Experiment 4 showed that perceptions of meaningfulness partially mediate the martyrdom effect. Finally, Experiment 5 demonstrated that the nature of the prosocial cause moderates the martyrdom effect: the effect is strongest for causes associated with human suffering. We propose that anticipated pain and effort lead people to ascribe greater meaning to their contributions and to the experience of contributing, thereby motivating higher prosocial contributions. We conclude by considering some implications of this puzzling phenomenon. Copyright © 2011 John Wiley & Sons, Ltd. PMID:23559692

  5. Microbial Community Response during the Iron Fertilization Experiment LOHAFEX

    PubMed Central

    Thiele, Stefan; Ramaiah, Nagappa; Amann, Rudolf

    2012-01-01

    Iron fertilization experiments in high-nutrient, low-chlorophyll areas are known to induce phytoplankton blooms. However, little is known about the response of the microbial community upon iron fertilization. As part of the LOHAFEX experiment in the southern Atlantic Ocean, Bacteria and Archaea were monitored within and outside an induced bloom, dominated by Phaeocystis-like nanoplankton, during the 38 days of the experiment. The microbial production increased 1.6-fold (thymidine uptake) and 2.1-fold (leucine uptake), while total cell numbers increased only slightly over the course of the experiment. 454 tag pyrosequencing of partial 16S rRNA genes and catalyzed reporter deposition fluorescence in situ hybridization (CARD FISH) showed that the composition and abundance of the bacterial and archaeal community in the iron-fertilized water body were remarkably constant without development of typical bloom-related succession patterns. Members of groups usually found in phytoplankton blooms, such as Roseobacter and Gammaproteobacteria, showed no response or only a minor response to the bloom. However, sequence numbers and total cell numbers of the SAR11 and SAR86 clades increased slightly but significantly toward the end of the experiment. It seems that although microbial productivity was enhanced within the fertilized area, a succession-like response of the microbial community upon the algal bloom was averted by highly effective grazing. Only small-celled members like the SAR11 and SAR86 clades could possibly escape the grazing pressure, explaining a net increase of those clades in numbers. PMID:23064339

  6. Social control, social learning, and cheating: Evidence from lab and online experiments on dishonesty.

    PubMed

    Kroher, Martina; Wolbring, Tobias

    2015-09-01

    Varying the conditions of the decision-making environment we offered participants the opportunity to increase their payoff by undetectable lies. In addition to a baseline treatment, in which subjects rolled a die in private and showed a high extent of dishonest behavior, we increased the degree of social control by a novel treatment in which subjects played in randomly assigned pairs of two. The presence of others proved to substantially, but only temporarily reduce dishonest behavior. Furthermore, one treatment group received feedback on unethical behavior of participants in a similar experiment. Knowing that others betrayed in the experiment facilitated social learning and led to a higher prevalence of cheating. Finally, increasing the degree of anonymity by re-running the experiment online increased the extent of norm transgressions slightly. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Adolescent Attachment Trajectories with Mothers and Fathers: The Importance of Parent-Child Relationship Experiences and Gender

    PubMed Central

    Ruhl, Holly; Dolan, Elaine A.; Buhrmester, Duane

    2014-01-01

    This longitudinal study investigated how attachment with mothers and fathers changes during adolescence, and how gender and parent-child relationship experiences are associated with attachment trajectories. The relative importance of specific positive and negative relationship experiences on attachment trajectories was also examined. An initial sample of 223 adolescents reported on relationship experiences and attachment avoidance and anxiety with mothers and fathers in grades 6, 8, 10, and 12 (final N=110; Mage=11.90 years at onset, SD=.43). Mothers and fathers reported on relationship experiences with adolescents. Hierarchical linear modeling showed that security with parents increased during adolescence. Positive relationship experiences (companionship, satisfaction, approval, support) predicted increases in security and negative experiences (pressure, criticism) predicted decreases in security. Females reported less avoidance than males. PMID:26347590

  8. Experience with proactive interference diminishes its effects: mechanisms of change.

    PubMed

    Wahlheim, Christopher N; Jacoby, Larry L

    2011-02-01

    In three experiments, we examined the mechanisms by which prior experience with proactive interference (PI) diminished its effects. Cued recall tasks conforming to an A-B, A-D paradigm were used to induce PI effects. Experiment 1 showed that reduced PI was not due to a reduction in attention to the source of PI. Experiment 2 revealed that participants' awareness of PI effects on memory performance increased with experience, resulting in a shift in encoding processes. Experiment 3 demonstrated that changes in encoding provided additional support for recollection that further enhanced participants' ability to constrain their retrieval processing to the appropriate source of information at the time of test. These results can be interpreted as showing that experience with PI enhances awareness of its effects and allows individuals to adjust their learning and retrieval strategies to compensate for such effects.

  9. Reinforced spatial alternation as an animal model of obsessive-compulsive disorder (OCD): investigation of 5-HT2C and 5-HT1D receptor involvement in OCD pathophysiology.

    PubMed

    Tsaltas, Eleftheria; Kontis, Dimitris; Chrysikakou, Sofia; Giannou, Haralambos; Biba, Angeliki; Pallidi, Stella; Christodoulou, Angeliki; Maillis, Antonis; Rabavilas, Andreas

    2005-05-15

    This study introduces a laboratory model of compulsive behavior based on persistence in the context of rewarded spatial alternation. Rats were screened for spontaneous persistence during T-maze reinforced alternation. Experiment 1: One high and one low spontaneous persistence group (n = 8) received 20 injections of fluoxetine, a matched pair saline, both followed by 4 days of meta-chlorophenylpiperazine (mCPP) challenge. Experiment 2: Five matched groups of rats (n = 9) received pretreatment (20 injections) with fluoxetine, mCPP, desipramine, diazepam or saline, followed by 4 days of mCPP challenge (fluoxetine in mCPP group). After washout, animals received 2 days of naratriptan, followed by another 2-day mCPP challenge. In both experiments mCPP significantly increased persistence in saline controls. Fluoxetine also acutely increased persistence scores: after a gradual return to baseline, these scores showed tolerance to mCPP. Experiment 1: This pattern was significant in high but not low initial persistence groups. Experiment 2: Fluoxetine and mCPP showed cross-tolerance. Neither desipramine nor diazepam protected against mCPP challenge. Persistence scores returned to baseline during washout and naratriptan and were thereafter increased by another mCPP challenge in all but the fluoxetine and mCPP groups, suggesting 5-HT2C receptor mediation. This model is based on spontaneous persistence behavior showing pharmacological responses concordant with those of compulsive symptomatology.

  10. Processing changes across reading encounters.

    PubMed

    Levy, B A; Newell, S; Snyder, J; Timmins, K

    1986-10-01

    Five experiments examined changes in the processing of a text across reading encounters. Experiment 1 showed that reading speed increased systematically across encounters, with no loss in the extensiveness of analyses of the printed text, as indicated by the ability to detect nonword errors embedded within that passage. Experiment 2 replicated this improved reading fluency with experience and showed that it occurred even with typescript changes across trials, thus indicating that a primed visual operations explanation cannot account for the effect. The third and fourth experiments then extended the study of the familiarity effect to higher level processing, as indicated by the detection of word errors. Familiarity facilitated the detection of these violations at the syntactic-semantic levels. Finally, Experiment 5 showed that these higher level violations continued to be well detected over a series of reading encounters with the same text. The results indicate that prior experience improves reading speed, with no attenuation of analysis of the printed words or of the passage's message.

  11. The many lives of experiments: Wilhelm Johannsen, selection, hybridization, and the complex relations of genes and characters.

    PubMed

    Meunier, Robert

    2016-04-01

    In addition to his experiments on selection in pure lines, Wilhelm Johannsen (1857-1927) performed less well-known hybridisation experiments with beans. This article describes these experiments and discusses Johannsen's motivations and interpretations, in the context of developments in early genetics. I will show that Johannsen first presented the hybridisation experiments as an additional control for his selection experiments. The latter were dedicated to investigating heredity with respect to debates concerning the significance of natural selection of continuous variation for evolution. In the course of the establishment of a Mendelian research program after 1900, the study of heredity gained increasing independence from questions of evolution, and focused more on the modes and mechanisms of heredity. Further to their role as control experiments, Johannsen also saw his hybridisation experiments as contributing to the Mendelian program, by extending the scope of the principles of Mendelian inheritance to quantitative characters. Towards the end of the first decade of genetics, Johannsen revisited his experiments to illustrate the many-many relationship between genes and characters, at a time when that relationship appeared increasingly complex, and the unit-character concept, accordingly, became inadequate. For the philosophy of science, the example shows that experiments can have multiple roles in a research programme, and can be interpreted in the light of questions other than those that motivated the experiments in the first place.

  12. Enhanced attention amplifies face adaptation.

    PubMed

    Rhodes, Gillian; Jeffery, Linda; Evangelista, Emma; Ewing, Louise; Peters, Marianne; Taylor, Libby

    2011-08-15

    Perceptual adaptation not only produces striking perceptual aftereffects, but also enhances coding efficiency and discrimination by calibrating coding mechanisms to prevailing inputs. Attention to simple stimuli increases adaptation, potentially enhancing its functional benefits. Here we show that attention also increases adaptation to faces. In Experiment 1, face identity aftereffects increased when attention to adapting faces was increased using a change detection task. In Experiment 2, figural (distortion) face aftereffects increased when attention was increased using a snap game (detecting immediate repeats) during adaptation. Both were large effects. Contributions of low-level adaptation were reduced using free viewing (both experiments) and a size change between adapt and test faces (Experiment 2). We suggest that attention may enhance adaptation throughout the entire cortical visual pathway, with functional benefits well beyond the immediate advantages of selective processing of potentially important stimuli. These results highlight the potential to facilitate adaptive updating of face-coding mechanisms by strategic deployment of attentional resources. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Control deprivation and styles of thinking.

    PubMed

    Zhou, Xinyue; He, Lingnan; Yang, Qing; Lao, Junpeng; Baumeister, Roy F

    2012-03-01

    Westerners habitually think in analytical ways, whereas East Asians tend to favor holistic styles of thinking. We replicated this difference but showed that it disappeared after control deprivation (Experiment 1). Brief experiences of control deprivation, which stimulate increased desire for control, caused Chinese participants to shift toward Western-style analytical thinking in multiple ways (Experiments 2-5). Western Caucasian participants also increased their use of analytical thinking after control deprivation (Experiment 6). Manipulations that required Chinese participants to think in Western, analytical ways caused their sense of personal control to increase (Experiments 7-9). Prolonged experiences of control deprivation, which past work suggested foster an attitude more akin to learned helplessness than striving for control, had the opposite effect of causing Chinese participants to shift back toward a strongly holistic style of thinking (Experiments 10-12). Taken together, the results support the reality of cultural differences in cognition but also the cross-cultural similarity of using analytical thinking when seeking to enhance personal control.

  14. Action video game players and deaf observers have larger Goldmann visual fields.

    PubMed

    Buckley, David; Codina, Charlotte; Bhardwaj, Palvi; Pascalis, Olivier

    2010-03-05

    We used Goldmann kinetic perimetry to compare how training and congenital auditory deprivation may affect the size of the visual field. We measured the ability of action video game players and deaf observers to detect small moving lights at various locations in the central (around 30 degrees from fixation) and peripheral (around 60 degrees ) visual fields. Experiment 1 found that 10 habitual video game players showed significantly larger central and peripheral field areas than 10 controls. In Experiment 2 we found that 13 congenitally deaf observers had significantly larger visual fields than 13 hearing controls for both the peripheral and central fields. Here the greatest differences were found in the lower parts of the fields. Comparison of the two groups showed that whereas VGP players have a more uniform increase in field size in both central and peripheral fields deaf observers show non-uniform increases with greatest increases in lower parts of the visual field.

  15. The Escherichia coli Regulator of Sigma 70 Protein, Rsd, Can Up-Regulate Some Stress-Dependent Promoters by Sequestering Sigma 70▿

    PubMed Central

    Mitchell, Jennie E.; Oshima, Taku; Piper, Sarah E.; Webster, Christine L.; Westblade, Lars F.; Karimova, Gouzel; Ladant, Daniel; Kolb, Annie; Hobman, Jon L.; Busby, Stephen J. W.; Lee, David J.

    2007-01-01

    The Escherichia coli Rsd protein forms complexes with the RNA polymerase σ70 factor, but its biological role is not understood. Transcriptome analysis shows that overexpression of Rsd causes increased expression from some promoters whose expression depends on the alternative σ38 factor, and this was confirmed by experiments with lac fusions at selected promoters. The LP18 substitution in Rsd increases the Rsd-dependent stimulation of these promoter-lac fusions. Analysis with a bacterial two-hybrid system shows that the LP18 substitution in Rsd increases its interaction with σ70. Our experiments support a model in which the role of Rsd is primarily to sequester σ70, thereby increasing the levels of RNA polymerase containing the alternative σ38 factor. PMID:17351046

  16. Secondary analysis of hospital patient experience scores across England's National Health Service - How much has improved since 2005?

    PubMed

    Honeyford, Kate; Greaves, Felix; Aylin, Paul; Bottle, Alex

    2017-01-01

    To examine trends in patient experience and consistency between hospital trusts and settings. Observational study of publicly available patient experience surveys of three hospital settings (inpatients (IP), accident and emergency (A&E) and outpatients (OP)) of 130 acute NHS hospital trusts in England between 2004/05 and 2014/15. Overall patient experience has been good, showing modest improvements over time across the three hospital settings. Individual questions with the biggest improvement across all three settings are cleanliness (IP: +7.1, A&E: +6.5, OP: +4.7) and information about danger signals (IP: +3.8, A&E: +3.9, OP: +4.0). Trust performance has been consistent over time: 71.5% of trusts ranked in the same cluster for more than five years. There is some consistency across settings, especially between outpatients and inpatients. The lowest-scoring questions, regarding information at discharge, are the same in all years and all settings. The greatest improvement across all three settings has been for cleanliness, which has seen national policies and targets. Information about danger signals and medication side-effects showed least consistency across settings and scores have remained low over time, despite information about danger signals showing a big increase in score. Patient experience of aspects of access and waiting have declined, as has experience of discharge delay, likely reflecting known increases in pressure on England's NHS.

  17. The counterfeit self: the deceptive costs of faking it.

    PubMed

    Gino, Francesca; Norton, Michael I; Ariely, Dan

    2010-05-01

    Although people buy counterfeit products to signal positive traits, we show that wearing counterfeit products makes individuals feel less authentic and increases their likelihood of both behaving dishonestly and judging others as unethical. In four experiments, participants wore purportedly fake or authentically branded sunglasses. Those wearing fake sunglasses cheated more across multiple tasks than did participants wearing authentic sunglasses, both when they believed they had a preference for counterfeits (Experiment 1a) and when they were randomly assigned to wear them (Experiment 1b). Experiment 2 shows that the effects of wearing counterfeit sunglasses extend beyond the self, influencing judgments of other people's unethical behavior. Experiment 3 demonstrates that the feelings of inauthenticity that wearing fake products engenders-what we term the counterfeit self-mediate the impact of counterfeits on unethical behavior. Finally, we show that people do not predict the impact of counterfeits on ethicality; thus, the costs of counterfeits are deceptive.

  18. Learning curve for hysteroscopic sterilisation: lessons from the first 80 cases.

    PubMed

    Rosen, David M B

    2004-02-01

    The present report looks at the first 80 patients of Essure sterilisation performed by a surgeon with experience in operative hysteroscopy. The results show that the procedure is well tolerated under local anaesthesia with or without sedation, and that devices can be successfully placed in 90% of cases. Surgical time is reduced with increased experience, and successful placement increased by improving visibility within the endometrial cavity (cycle timing).

  19. Taking the CCDs to the ultimate performance for low threshold experiments

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

    Haro, Miguel; Moroni, Guillermo; Tiffenberg, Javier

    2016-11-14

    Scientific grade CCDs show atractive capabilities for the detection of particles with small energy deposition in matter. Their very low threshold of approximately 40 eV and their good spatial reconstruction of the event are key properties for currently running experiments: CONNIE and DAMIC. Both experiments can benefit from any increase of the detection efficiency of nuclear recoils at low energy. In this work we present two different approaches to increase this efficiency by increasing the SNR of events. The first one is based on the reduction of the readout noise of the device, which is the main contribution of uncertaintymore » to the signal measurement. New studies on the electronic noise from the integrated output amplifier and the readout electronics will be presented together with result of a new configuration showing a lower limit on the readout noise which can be implemented on the current setup of the CCD based experiments. A second approach to increase the SNR of events at low energy that will be presented is the studies of the spatial conformation of nuclear recoil events at different depth in the active volume by studies of new effects that differ from expected models based on not interacting diffusion model of electrons in the semiconductor.« less

  20. Excessive response-repetition costs under task switching: how response inhibition amplifies response conflict.

    PubMed

    Grzyb, Kai Robin; Hübner, Ronald

    2013-01-01

    The size of response-repetition (RR) costs, which are usually observed on task-switch trials, strongly varies between conditions with univalent and bivalent stimuli. To test whether top-down or bottom-up processes can account for this effect, we assessed in Experiment 1 baselines for univalent and bivalent stimulus conditions (i.e., for stimuli that are associated with either 1 or 2 tasks). Experiment 2 examined whether the proportion of these stimulus types affects RR costs. As the size of RR costs was independent of proportion, a top-down explanation could be excluded. However, there was an increase in RR costs if the current stimulus induced a response conflict. To account for this effect, we proposed an amplification of response conflict account. It assumes that the basic mechanism that leads to RR costs amplifies response conflict, which, in turn, increases RR costs. Experiment 3 confirmed this bottom-up explanation by showing that the increase in RR costs varies with previous-trial congruency, which is known to affect RR costs. Experiment 4 showed that the increase can also be found with univalent stimuli that induce response conflict. Altogether, the results are in line with a response inhibition account of RR costs. Implications for alternative accounts are also discussed. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  1. Colocalization of Mating-Induced Fos and D2-Like Dopamine Receptors in the Medial Preoptic Area: Influence of Sexual Experience.

    PubMed

    Nutsch, Victoria L; Will, Ryan G; Robison, Christopher L; Martz, Julia R; Tobiansky, Daniel J; Dominguez, Juan M

    2016-01-01

    Dopamine in the medial preoptic area (mPOA) stimulates sexual activity in males. This is evidenced by microdialysis and microinjection experiments revealing that dopamine receptor antagonists in the mPOA inhibit sexual activity, whereas agonists facilitate behavior. Microdialysis experiments similarly show a facilitative role for dopamine, as levels of dopamine in the mPOA increase with mating. While the majority of evidence suggests an important role for dopamine receptors in the mPOA in the regulation of male sexual behaviors, whether sexual activity or sexual experience influence dopamine receptor function in the mPOA has not been previously shown. Here we used immunohistochemical assays to determine whether varying levels of sexual activity or experience influence the number of cells containing Fos or D2 receptor immunoreactivity. Results show that sexual experience facilitated subsequent behavior, namely experience decreased latencies. Moreover, the number of cells with immunoreactivity for Fos or D2 correlated with levels of sexual experience and sexual activity. Sexual activity increased Fos immunoreactivity. Sexually experienced animals also had significantly more D2-positive cells. Sexually inexperienced animals copulating for the first time had a larger percentage of D2-positive cells containing Fos, when compared to sexually experienced animals. Finally, regardless of experience, animals that had sex prior to sacrifice had significantly more D2-positive cells that contained Fos, vs. animals that did not copulate. These findings are noteworthy because sexually experienced animals display increased sexual efficiency. The differences in activation of D2 and changes in receptor density may play a role in this efficiency and other behavioral changes across sexual experience.

  2. Power Analysis of Artificial Selection Experiments Using Efficient Whole Genome Simulation of Quantitative Traits

    PubMed Central

    Kessner, Darren; Novembre, John

    2015-01-01

    Evolve and resequence studies combine artificial selection experiments with massively parallel sequencing technology to study the genetic basis for complex traits. In these experiments, individuals are selected for extreme values of a trait, causing alleles at quantitative trait loci (QTL) to increase or decrease in frequency in the experimental population. We present a new analysis of the power of artificial selection experiments to detect and localize quantitative trait loci. This analysis uses a simulation framework that explicitly models whole genomes of individuals, quantitative traits, and selection based on individual trait values. We find that explicitly modeling QTL provides qualitatively different insights than considering independent loci with constant selection coefficients. Specifically, we observe how interference between QTL under selection affects the trajectories and lengthens the fixation times of selected alleles. We also show that a substantial portion of the genetic variance of the trait (50–100%) can be explained by detected QTL in as little as 20 generations of selection, depending on the trait architecture and experimental design. Furthermore, we show that power depends crucially on the opportunity for recombination during the experiment. Finally, we show that an increase in power is obtained by leveraging founder haplotype information to obtain allele frequency estimates. PMID:25672748

  3. Fundamental frequency discrimination and speech perception in noise in cochlear implant simulationsa)

    PubMed Central

    Carroll, Jeff; Zeng, Fan-Gang

    2007-01-01

    Increasing the number of channels at low frequencies improves discrimination of fundamental frequency (F0) in cochlear implants [Geurts and Wouters 2004]. We conducted three experiments to test whether improved F0 discrimination can be translated into increased speech intelligibility in noise in a cochlear implant simulation. The first experiment measured F0 discrimination and speech intelligibility in quiet as a function of channel density over different frequency regions. The results from this experiment showed a tradeoff in performance between F0 discrimination and speech intelligibility with a limited number of channels. The second experiment tested whether improved F0 discrimination and optimizing this tradeoff could improve speech performance with a competing talker. However, improved F0 discrimination did not improve speech intelligibility in noise. The third experiment identified the critical number of channels needed at low frequencies to improve speech intelligibility in noise. The result showed that, while 16 channels below 500 Hz were needed to observe any improvement in speech intelligibility in noise, even 32 channels did not achieve normal performance. Theoretically, these results suggest that without accurate spectral coding, F0 discrimination and speech perception in noise are two independent processes. Practically, the present results illustrate the need to increase the number of independent channels in cochlear implants. PMID:17604581

  4. Analysis of sharpness increase by image noise

    NASA Astrophysics Data System (ADS)

    Kurihara, Takehito; Aoki, Naokazu; Kobayashi, Hiroyuki

    2009-02-01

    Motivated by the reported increase in sharpness by image noise, we investigated how noise affects sharpness perception. We first used natural images of tree bark with different amounts of noise to see whether noise enhances sharpness. Although the result showed sharpness decreased as noise amount increased, some observers seemed to perceive more sharpness with increasing noise, while the others did not. We next used 1D and 2D uni-frequency patterns as stimuli in an attempt to reduce such variability in the judgment. The result showed, for higher frequency stimuli, sharpness decreased as the noise amount increased, while sharpness of the lower frequency stimuli increased at a certain noise level. From this result, we thought image noise might reduce sharpness at edges, but be able to improve sharpness of lower frequency component or texture in image. To prove this prediction, we experimented again with the natural image used in the first experiment. Stimuli were made by applying noise separately to edge or to texture part of the image. The result showed noise, when added to edge region, only decreased sharpness, whereas when added to texture, could improve sharpness. We think it is the interaction between noise and texture that sharpens image.

  5. Short-term nutritional treatments grazing legumes or feeding concentrates increase prolificacy in Corriedale ewes.

    PubMed

    Viñoles, C; Meikle, A; Martin, G B

    2009-07-01

    We tested whether short periods of increased nutrition will improve ovulation rate and prolificacy, irrespective of the method used to synchronise the cycles of the ewes. In Experiment 1, we used 138 Corriedale ewes to evaluate two factors: synchronization treatment (sponges versus a single injection of prostaglandin) and type of pasture (native versus improved with Lotus corniculatus). Ewes were mated at the end of the grazing period and prolificacy was evaluated at lambing. Grazing Lotus corniculatus for 12 days tended to increase the number of twin lambs born (P=0.09). The percentage of ewes showing oestrus during a 9-day period was similar among synchronization treatments. Animals in Experiments 2 (n=282) and 3 (n=288) were allocated to a control group or a group fed a supplement of corn grain and soybean meal for 7 days. Ewes received 2 prostaglandin injections and the supplement was fed from Days 11 to 17 after the second prostaglandin. Ovulation rate was measured in 65 (Experiment 2) and 61 (Experiment 3) ewes that were confirmed to have consumed the supplement and showed oestrus in a 4-day period. The supplement increased ovulation rate by 14% in both experiments (P<0.05). We conclude that Corriedale ewes can respond with increases in prolificacy to a 12-day period grazing Lotus corniculatus and in ovulation rate to 7 days feeding with a supplement rich in energy and protein. Moreover, in these studies, prostaglandin was as effective as sponges for synchronising oestrus, an important factor in future decisions about hormonal management of fertility.

  6. Negative Experiences as Learning Trigger: A Play Experience Empirical Research on a Game for Social Change Case Study

    ERIC Educational Resources Information Center

    Mariani, Ilaria; Gandolfi, Enrico

    2016-01-01

    This study shows the results gathered from 141 subjects playing the persuasive urban game "A Hostile World" via a post-game-experience quantitative questionnaire. The aim is to problematize and deepen the role of negative emotions (e.g., frustration, rage)--explicitly fostered by "A Hostile World" to increase empathy toward…

  7. Reduced adaptability, but no fundamental disruption, of norm-based face coding following early visual deprivation from congenital cataracts.

    PubMed

    Rhodes, Gillian; Nishimura, Mayu; de Heering, Adelaide; Jeffery, Linda; Maurer, Daphne

    2017-05-01

    Faces are adaptively coded relative to visual norms that are updated by experience, and this adaptive coding is linked to face recognition ability. Here we investigated whether adaptive coding of faces is disrupted in individuals (adolescents and adults) who experience face recognition difficulties following visual deprivation from congenital cataracts in infancy. We measured adaptive coding using face identity aftereffects, where smaller aftereffects indicate less adaptive updating of face-coding mechanisms by experience. We also examined whether the aftereffects increase with adaptor identity strength, consistent with norm-based coding of identity, as in typical populations, or whether they show a different pattern indicating some more fundamental disruption of face-coding mechanisms. Cataract-reversal patients showed significantly smaller face identity aftereffects than did controls (Experiments 1 and 2). However, their aftereffects increased significantly with adaptor strength, consistent with norm-based coding (Experiment 2). Thus we found reduced adaptability but no fundamental disruption of norm-based face-coding mechanisms in cataract-reversal patients. Our results suggest that early visual experience is important for the normal development of adaptive face-coding mechanisms. © 2016 John Wiley & Sons Ltd.

  8. Surgical Space Suits Increase Particle and Microbiological Emission Rates in a Simulated Surgical Environment.

    PubMed

    Vijaysegaran, Praveen; Knibbs, Luke D; Morawska, Lidia; Crawford, Ross W

    2018-05-01

    The role of space suits in the prevention of orthopedic prosthetic joint infection remains unclear. Recent evidence suggests that space suits may in fact contribute to increased infection rates, with bioaerosol emissions from space suits identified as a potential cause. This study aimed to compare the particle and microbiological emission rates (PER and MER) of space suits and standard surgical clothing. A comparison of emission rates between space suits and standard surgical clothing was performed in a simulated surgical environment during 5 separate experiments. Particle counts were analyzed with 2 separate particle counters capable of detecting particles between 0.1 and 20 μm. An Andersen impactor was used to sample bacteria, with culture counts performed at 24 and 48 hours. Four experiments consistently showed statistically significant increases in both PER and MER when space suits are used compared with standard surgical clothing. One experiment showed inconsistent results, with a trend toward increases in both PER and MER when space suits are used compared with standard surgical clothing. Space suits cause increased PER and MER compared with standard surgical clothing. This finding provides mechanistic evidence to support the increased prosthetic joint infection rates observed in clinical studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Further evaluation of methods to identify matched stimulation.

    PubMed

    Rapp, John T

    2007-01-01

    The effects of preferred stimulation on the vocal stereotypy of 2 individuals were evaluated in two experiments. The results of Experiment 1 showed that (a) the vocal stereotypy of both participants persisted in the absence of social consequences, (b) 1 participant manipulated toys that did and did not produce auditory stimulation, but only sound-producing toys decreased his vocal stereotypy, and (c) only noncontingent music decreased vocal stereotypy for the other participant, but sterotypy paradoxically increased when toys were presented with music. Using a three-component multiple schedule, the results of Experiment 2 showed that the vocal stereotypy of both participants remained below preintervention levels following the removal of auditory stimulation and that 1 participant's vocal stereotypy increased following the removal of contingent reprimands. These patterns suggest that auditory stimulation functioned as an abolishing operation for vocal stereotypy and reprimands functioned as an establishing operation for vocal stereotypy. Together, the two experiments provide a method for identifying alternative stimulation that may substitute for automatically reinforced behavior.

  10. Combined Dextroamphetamine and Transcranial Direct Current Stimulation in Poststroke Aphasia.

    PubMed

    Keser, Zafer; Dehgan, Michelle Weber; Shadravan, Shaparak; Yozbatiran, Nuray; Maher, Lynn M; Francisco, Gerard E

    2017-10-01

    There is a growing need for various effective adjunctive treatment options for speech recovery after stroke. A pharmacological agent combined with noninvasive brain stimulation has not been previously reported for poststroke aphasia recovery. In this "proof of concept" study, we aimed to test the safety of a combined intervention consisting of dextroamphetamine, transcranial direct current stimulation, and speech and language therapy in subjects with nonfluent aphasia. Ten subjects with chronic nonfluent aphasia underwent two experiments where they received dextroamphetamine or placebo along with transcranial direct current stimulation and speech and language therapy on two separate days. The Western Aphasia Battery-Revised was used to monitor changes in speech performance. No serious adverse events were observed. There was no significant increase in blood pressure with amphetamine or deterioration in speech and language performance. Western Aphasia Battery-Revised aphasia quotient and language quotient showed a statistically significant increase in the active experiment. Comparison of proportional changes of aphasia quotient and language quotient in active experiment with those in placebo experiment showed significant difference. We showed that the triple combination therapy is safe and implementable and seems to induce positive changes in speech and language performance in the patients with chronic nonfluent aphasia due to stroke.

  11. Power, propensity to negotiate, and moving first in competitive interactions.

    PubMed

    Magee, Joe C; Galinsky, Adam D; Gruenfeld, Deborah H

    2007-02-01

    Five experiments investigated how the possession and experience of power affects the initiation of competitive interaction. In Experiments 1a and 1b, high-power individuals displayed a greater propensity to initiate a negotiation than did low-power individuals. Three additional experiments showed that power increased the likelihood of making the first move in a variety of competitive interactions. In Experiment 2, participants who were semantically primed with power were nearly 4 times as likely as participants in a control condition to choose to make the opening arguments in a debate competition scenario. In Experiment 3, negotiators with strong alternatives to a negotiation were more than 3 times as likely to spontaneously express an intention to make the first offer compared to participants who lacked any alternatives. Experiment 4 showed that high-power negotiators were more likely than low-power negotiators to actually make the first offer and that making the first offer produced a bargaining advantage.

  12. In Sickness and in Health: The Co-Regulation of Inflammation and Social Behavior

    PubMed Central

    Eisenberger, Naomi I; Moieni, Mona; Inagaki, Tristen K; Muscatell, Keely A; Irwin, Michael R

    2017-01-01

    Although it has commonly been assumed that the immune system and the processes that govern social behavior are separate, non-communicating entities, research over the past several decades suggests otherwise. Considerable evidence now shows that inflammatory processes and social behavior are actually powerful regulators of one another. This review first summarizes evidence that inflammatory processes regulate social behavior, leading to characteristic changes that may help an individual navigate the social environment during times of sickness. Specifically, this review shows that inflammation: (1) increases threat-related neural sensitivity to negative social experiences (eg, rejection, negative social feedback), presumably to enhance sensitivity to threats to well-being or safety in order to avoid them and (2) enhances reward-related neural sensitivity to positive social experiences (eg, viewing close others and receiving positive social feedback), presumably to increase approach-related motivation towards others who might provide support and care during sickness. Next, this review summarizes evidence showing that social behavior also regulates aspects of inflammatory activity, preparing the body for situations in which wounding and infection may be more likely (social isolation). Here, we review research showing: (1) that exposure to social stressors increases proinflammatory activity, (2) that individuals who are more socially isolated (ie, lonely) show increased proinflammatory activity, and (3) that individuals who are more socially isolated show increased proinflammatory activity in response to an inflammatory challenge or social stressor. The implications of the co-regulation of inflammation and social behavior are discussed. PMID:27480575

  13. Adverse childhood experience and asthma onset: a systematic review.

    PubMed

    Exley, Daniel; Norman, Alyson; Hyland, Michael

    2015-06-01

    Adverse childhood experiences such as abuse and neglect are associated with subsequent immune dysregulation. Some studies show an association between adverse childhood experiences and asthma onset, although significant disparity in results exists in the published literature. We aimed to review available studies employing a prospective design that investigates associations between adverse childhood experience and asthma. A search protocol was developed and studies were drawn from four electronic journal databases. Studies were selected in accordance with pre-set inclusion criteria and relevant data were extracted. 12 studies, assessing data from a total of 31 524 individuals, were identified that investigate the impact of a range of adverse childhood experiences on the likelihood of developing asthma. Evidence suggests that chronic stress exposure and maternal distress in pregnancy operate synergistically with known triggers such as traffic-related air pollution to increase asthma risk. Chronic stress in early life is associated with an increased risk of asthma onset. There is evidence that adverse childhood experience increases the impact of traffic-related air pollution and inconsistent evidence that adverse childhood experience has an independent effect on asthma onset. Copyright ©ERS 2015.

  14. Isolation and characterization of chromosome-gain and increase-in-ploidy mutants in yeast.

    PubMed

    Chan, C S; Botstein, D

    1993-11-01

    We have developed a colony papillation assay for monitoring the copy number of genetically marked chromosomes II and III in Saccharomyces cerevisiae. The unique feature of this assay is that it allows detection of a gain of the marked chromosomes even if there is a gain of the entire set of chromosomes (increase-in-ploidy). This assay was used to screen for chromosome-gain or increase-in-ploidy mutants. Five complementation groups have been defined for recessive mutations that confer an increase-in-ploidy (ipl) phenotype, which, in each case, cosegregates with a temperature-sensitive growth phenotype. Four new alleles of CDC31, which is required for spindle pole body duplication, were also recovered from this screen. Temperature-shift experiments with ipl1 cells show that they suffer severe nondisjunction at 37 degrees. Similar experiments with ipl2 cells show that they gain entire sets of chromosomes and become arrested as unbudded cells at 37 degrees. Molecular cloning and genetic mapping show that IPL1 is a newly identified gene, whereas IPL2 is allelic to BEM2, which is required for normal bud growth.

  15. Application of 23Na MRI to Monitor Chemotherapeutic Response in RIF-1 Tumors1

    PubMed Central

    Babsky, Andriy M; Hekmatyar, Shahryar K; Zhang, Hong; Solomon, James L; Bansal, Navin

    2005-01-01

    Abstract Effects of an alkylating anticancer drug, cyclophosphamide (Cp), on 23Na signal intensity (23Na SI) and water apparent diffusion coefficient (ADC) were examined in subcutaneously-implanted radiation-induced fibrosarcoma (RIF-1) tumors by in vivo 23Na and 1H magnetic resonance imaging (MRI). MRI experiments were performed on untreated control (n = 5) and Cp-treated (n = 6) C3H mice, once before Cp injection (300 mg/kg) then daily for 3 days after treatment. Tumor volumes were significantly lower in treated animals 2 and 3 days posttreatment. At the same time points, MRI experiments showed an increase in both 23Na SI and water ADC in treated tumors, whereas control tumors did not show any significant changes. The correlation between 23Na SI and water ADC changes was dramatically increased in the Cp-treated group, suggesting that the observed increases in 23Na SI and water ADC were caused by the same mechanism. Histologic sections showed decreased cell density in the regions of increased 23Na and water ADC SI. Destructive chemical analysis showed that Cp treatment increased the relative extracellular space and tumor [Na+]. We conclude that the changes in water ADC and 23Na SI were largely due to an increase in extracellular space. 23Na MRI and 1H water ADC measurements may provide valuable noninvasive techniques for monitoring chemotherapeutic responses. PMID:16026645

  16. Early social enrichment provided by communal nest increases resilience to depression-like behavior more in female than in male mice.

    PubMed

    D'Andrea, Ivana; Gracci, Fiorenza; Alleva, Enrico; Branchi, Igor

    2010-12-20

    Early experiences produce persistent changes in behavior and brain function. Being reared in a communal nest (CN), consisting of a single nest where three mouse mothers keep their pups together and share care-giving behavior from birth to weaning, provides an highly stimulating social environment to the developing pup since both mother-offspring and peer-to-peer interactions are markedly increased. Here we show that being reared in a CN affects adult behavior of CD-1 mice in a gender-dependent fashion, with reduced depression-like responses in females and increased anxiety-like behavior in males. In particular, CN females showed higher sucrose preference at baseline condition, drinking more sweet solution compared to female mice reared in a standard laboratory condition (SN). In the isolation test, both SN and CN females showed a reduction in sucrose preference after exposure to isolation stress. However, after 24h, only CN females significantly recovered. Finally, in the forced swim test, compared to SN, CN females spent longer time floating, a behavioral response that in the CN model has been inversely associated with display of endophenotypes of depression. With regard to the emotional response, CN males displayed an increased anxiety-like behavior in comparison to SN, spending less time in the open arms and displaying reduced head-dippings in the elevated plus-maze test. No difference was found in females. Overall, our findings show that gender and early experiences interact in modulating adult behavior. In particular, we show that early experiences modified developmental trajectories shaping adult endophenotypes of depression more markedly in females than in males. Copyright 2010 Elsevier B.V. All rights reserved.

  17. Understanding the Role of the ‘Self’ in the Social Priming of Mimicry

    PubMed Central

    Wang, Yin; Hamilton, Antonia F de C

    2013-01-01

    People have a tendency to unconsciously mimic other's actions. This mimicry has been regarded as a prosocial response which increases social affiliation. Previous research on social priming of mimicry demonstrated an assimilative relationship between mimicry and prosociality of the primed construct: prosocial primes elicit stronger mimicry whereas antisocial primes decrease mimicry. The present research extends these findings by showing that assimilative and contrasting prime-to-behavior effect can both happen on mimicry. Specifically, experiment 1 showed a robust contrast priming effect where priming antisocial behaviors induces stronger mimicry than priming prosocial behaviors. In experiment 2, we manipulated the self-relatedness of the pro/antisocial primes and further revealed that prosocial primes increase mimicry only when the social primes are self-related whereas antisocial primes increase mimicry only when the social primes are self-unrelated. In experiment 3, we used a novel cartoon movie paradigm to prime pro/antisocial behaviors and manipulated the perspective-taking when participants were watching these movies. Again, we found that prosocial primes increase mimicry only when participants took a first-person point of view whereas antisocial primes increase mimicry only when participants took a third-person point of view, which replicated the findings in experiment 2. We suggest that these three studies can be best explained by the active-self theory, which claims that the direction of prime-to-behavior effects depends on how primes are processed in relation to the ‘self’. PMID:23565208

  18. Edge wrinkling of a soft ridge with gradient thickness

    NASA Astrophysics Data System (ADS)

    Zhao, Yan; Shao, Zhi-Chun; Li, Guo-Yang; Zheng, Yang; Zhang, Wan-Yu; Li, Bo; Cao, Yanping; Feng, Xi-Qiao

    2017-06-01

    We investigate the edge wrinkling of a soft ridge with gradient thickness under axial compression. Our experiments show that the wrinkling wavelength undergoes a considerable increase with increasing load. Simple scaling laws are derived based on an upper-bound analysis to predict the critical buckling conditions and the evolution of wrinkling wavelength during the post-buckling stage, and the results show good accordance with our finite element simulations and experiments. We also report a pattern transformation triggered by the edge wrinkling of soft ridge arrays. The results and method not only help understand the correlation between the growth and form observed in some natural systems but also inspire a strategy to fabricate advanced functional surfaces.

  19. An MDOE Assessment of Nozzle Vanes for High Bypass Ratio Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Henderson, Brenda; Norum, Thomas; Bridges, James

    2006-01-01

    The effect of airfoil-shaped vanes placed in the fan stream of a BPR 8 coannular nozzle model system on the resulting jet noise was investigated. The experiments used a Modern Design of Experiments approach to investigate the impact of a range of vane parameters on the noise reduction achieved at representative takeoff conditions. The experimental results showed that the installation of the vanes decreased low frequency noise radiation in the downstream peak-noise direction and increased high frequency noise in the upstream direction. Results also showed that improper selection of the vane configuration resulted in increased low frequency noise radiation in the upstream direction. Large angles of attack are shown to reduce noise near the peak jet noise angle and increase noise in the upstream direction. The MDOE analysis yields an optimum design that minimizes perceived noise levels. Limited data taken with a BPR 5 nozzle system showed that the vanes result in better effective perceived noise reduction for lower bypass ratio nozzles than for the BPR 8 model.

  20. Solo status and self-construal: being distinctive influences racial self-construal and performance apprehension in African American women.

    PubMed

    Sekaquaptewa, Denise; Waldman, Andrew; Thompson, Mischa

    2007-10-01

    A preliminary study and main experiment tested the hypothesis that racial solo status (being the only member of one's race in a group) increases racial self-construal among African Americans. The preliminary study showed that African American men and women reported greater collectivist (i.e., group-based) over individualist self-construal under solo compared to nonsolo status, whereas Whites did not. The main experiment showed that the increased collectivism among African American solo women appears to be strongly reflected in racial identity becoming a salient aspect of self-construal. African American participants were also more likely than Whites to perceive that their anticipated performance would be generalized to their race, to feel like representatives of their race, and to show greater performance apprehension (indirectly evidenced by increased self-handicapping) when in racial solo status. The implications of solo status for African Americans in evaluative situations (such as academic testing sessions) are discussed. 2007 APA

  1. Conditions of Practice in Perceptual Skill Learning

    ERIC Educational Resources Information Center

    Memmert, D.; Hagemann, N.; Althoetmar, R.; Geppert, S.; Seiler, D.

    2009-01-01

    This study uses three experiments with different kinds of training conditions to investigate the "easy-to-hard" principle, context interference conditions, and feedback effects for learning anticipatory skills in badminton. Experiment 1 (N = 60) showed that a training program that gradually increases the difficulty level has no advantage over the…

  2. An Intensive Cultural Experience in a Rural Area.

    ERIC Educational Resources Information Center

    Thomas, Mary Durand; Olivares, Sergio A.; Kim, Hyun Jung; Beilke, Cheryle

    2003-01-01

    Discusses how, following an intensive 2-day clinical experience for nursing students in a rural, culturally diverse region, student evaluations and papers showed evidence of cultural learning and increased knowledge of rural health care systems. Includes reflections by a teaching associate and two students. (Contains 33 references.) (SK)

  3. A Lot of Good Physics in the Cartesian Diver

    ERIC Educational Resources Information Center

    De Luca, Roberto; Ganci, Salvatore

    2011-01-01

    The Cartesian diver experiment certainly occupies a place of honour in old physics textbooks as a vivid demonstration of Archimedes' buoyancy. The original experiment, as described in old textbooks, shows Archimedes buoyancy qualitatively: when the increased weight of the diver is not counterbalanced by Archimedes' buoyancy, the diver sinks. When…

  4. Pavlovian Incubation of US Signal Value

    ERIC Educational Resources Information Center

    Goddard, Murray J.

    2013-01-01

    Four experiments with rats examined Pavlovian incubation, in which responding increases when Pavlovian conditioning is followed by a testing delay. In a within-subjects design, Experiment 1 first showed that when a single food pellet unconditioned stimulus (US) signaled the delivery of three additional pellets, responding after the single US was…

  5. Is Perruchet's dissociation between eyeblink conditioned responding and outcome expectancy evidence for two learning systems?

    PubMed

    Weidemann, Gabrielle; Tangen, Jason M; Lovibond, Peter F; Mitchell, Christopher J

    2009-04-01

    P. Perruchet (1985b) showed a double dissociation of conditioned responses (CRs) and expectancy for an airpuff unconditioned stimulus (US) in a 50% partial reinforcement schedule in human eyeblink conditioning. In the Perruchet effect, participants show an increase in CRs and a concurrent decrease in expectancy for the airpuff across runs of reinforced trials; conversely, participants show a decrease in CRs and a concurrent increase in expectancy for the airpuff across runs of nonreinforced trials. Three eyeblink conditioning experiments investigated whether the linear trend in eyeblink CRs in the Perruchet effect is a result of changes in associative strength of the conditioned stimulus (CS), US sensitization, or learning the precise timing of the US. Experiments 1 and 2 demonstrated that the linear trend in eyeblink CRs is not the result of US sensitization. Experiment 3 showed that the linear trend in eyeblink CRs is present with both a fixed and a variable CS-US interval and so is not the result of learning the precise timing of the US. The results are difficult to reconcile with a single learning process model of associative learning in which expectancy mediates CRs. Copyright (c) 2009 APA, all rights reserved.

  6. Land–atmosphere feedbacks amplify aridity increase over land under global warming

    USGS Publications Warehouse

    Berg, Alexis; Findell, Kirsten; Lintner, Benjamin; Giannini, Alessandra; Seneviratne, Sonia I.; van den Hurk, Bart; Lorenz, Ruth; Pitman, Andy; Hagemann, Stefan; Meier, Arndt; Cheruy, Frédérique; Ducharne, Agnès; Malyshev, Sergey; Milly, Paul C. D.

    2016-01-01

    The response of the terrestrial water cycle to global warming is central to issues including water resources, agriculture and ecosystem health. Recent studies indicate that aridity, defined in terms of atmospheric supply (precipitation, P) and demand (potential evapotranspiration, Ep) of water at the land surface, will increase globally in a warmer world. Recently proposed mechanisms for this response emphasize the driving role of oceanic warming and associated atmospheric processes. Here we show that the aridity response is substantially amplified by land–atmosphere feedbacks associated with the land surface’s response to climate and CO2 change. Using simulations from the Global Land Atmosphere Coupling Experiment (GLACE)-CMIP5 experiment, we show that global aridity is enhanced by the feedbacks of projected soil moisture decrease on land surface temperature, relative humidity and precipitation. The physiological impact of increasing atmospheric CO2 on vegetation exerts a qualitatively similar control on aridity. We reconcile these findings with previously proposed mechanisms by showing that the moist enthalpy change over land is unaffected by the land hydrological response. Thus, although oceanic warming constrains the combined moisture and temperature changes over land, land hydrology modulates the partitioning of this enthalpy increase towards increased aridity.

  7. Gibraltar Experiment: Summary of the Field Program and Initial Results of the Gibraltar Experiment

    DTIC Science & Technology

    1988-08-01

    increasing knowledge of straiteffects on the adjacent ocean. Preliminary results show progress toward each of these four goals. 17. Document Analysis s ...derstanding the dynamical balances of the strait flow., developing strategies for long-term monitoring of the Strait, and increasing knowledge of strait...surrounding ocean and of the distinct nature of strait dynamics that is thus implied. An estimate based on data from the 1960’ s by Armi and Farmer (1985

  8. Lipotoxicity in HepG2 cells triggered by free fatty acids

    PubMed Central

    Yao, Hong-Rui; Liu, Jun; Plumeri, Daniel; Cao, Yong-Bing; He, Ting; Lin, Ling; Li, Yu; Jiang, Yuan-Ying; Li, Ji; Shang, Jing

    2011-01-01

    The goal of this study was to investigate the lipid accumulation and lipotoxicity of free fatty acids (FFAs) induced in HepG2 cells. HepG2 cells were co-incubated with various concentrations of FFAs for 24h and the intracellular lipid contents were observed by Oil Red O and Nile Red staining methods. The lipotoxicity of HepG2 cells were then detected by Hoechest 33342/PI, Annexin V-FITC/PI double-staining and 3-(4,5-dimethylthiazol-2-yl)-2,5-di phenyltetrazolium bromide (MTT) experiment tests. The experiments showed a lipid accumulation and lipotoxicity by increasing FFA concentration gradients. Through cell morphological observation and quantitative analysis, FFAs have shown to increase in a dose-dependent manner compared with the control group. The data collected from hoechst 33342/PI, annexin V-FITC/PI double staining and also MTT experiments showed that cell apoptosis and necrosis significantly increased with increasing FFA concentrations. Apoptosis was not obvious in the 1 mM FFAs-treated group compared to the other two groups. In a certain concentration range, FFAs induced intracellular lipid accumulation and lipotoxicity of HepG2 cells in a dose-dependent manner. PMID:21654881

  9. Altered Brain Long-Range Functional Interactions Underlying the Link Between Aberrant Self-experience and Self-other Relationship in First-Episode Schizophrenia

    PubMed Central

    Ebisch, Sjoerd J. H.; Mantini, Dante; Northoff, Georg; Salone, Anatolia; De Berardis, Domenico; Ferri, Francesca; Ferro, Filippo M.; Di Giannantonio, Massimo; Romani, Gian L.; Gallese, Vittorio

    2014-01-01

    Self-experience anomalies are elementary features of schizophrenic pathology. Such deficits can have a profound impact on self-other relationship, but how they are related through aberrant brain function remains poorly understood. In this functional magnetic resonance imaging (fMRI) study, we provide new evidence for a cortical link between aberrant self-experience and social cognition in first-episode schizophrenia (FES). As identified in previous studies, ventral premotor cortex (vPMC) and posterior insula (pIC) are candidate brain regions underlying disturbances in both self-experience and self-other relationship due to their processing of predominantly externally guided (vPMC; goal-oriented behavior) and internally guided (pIC; interoception) stimuli. Results from functional interaction analysis in a sample of 24 FES patients and 22 healthy controls show aberrant functional interactions (background/intrinsic connectivity) of right vPMC and bilateral pIC with posterior cingulate cortex (PCC), a midline region that has been shown central in mediating self-experience. More specifically, our results show increased functional coupling between vPMC and PCC, which positively correlated with basic symptoms (subjective self-experience disturbances). pIC showed reduced functional coupling with PCC and postcentral gyrus and increased functional interactions with anterior insula. Taken together, our results suggest an imbalance in the processing between internally and externally guided information and its abnormal integration with self-referential processing as mediated by PCC. Due to our correlation findings, we suggest this imbalance to be closely related to basic symptoms in FES and thus anomalous self-experience. The findings further disentangle the cortical basis of how self-experience anomalies may pervade the social domain. PMID:24191160

  10. Steroid hormones and maternal experience interact to induce glial plasticity in the cingulate cortex.

    PubMed

    Salmaso, N; Nadeau, J; Woodside, B

    2009-02-01

    Neocortical plasticity is not usually associated with changes in reproductive function. However, we have shown a six to 10-fold increase in the number of astrocytes labeled with glial fibrillary acidic protein (GFAP) and astrocytic basic fibroblast growth factor or FGF-2 (bFGF) in the cingulate cortex area 2 (Cg2) in postpartum rats, indicative of changes in connectivity in this area. In the present studies, we investigated the necessary and sufficient stimuli for these changes to occur. We show that 3 h of maternal experience combined with a hormonal treatment that mimics late pregnancy induces the astrocytic changes in Cg2 in virgin rats. The extent of these changes was similar to those of postpartum females. Sensitized virgin females did not show any astrocytic changes after 3 h of maternal behavior, suggesting that a similar amount of maternal experience alone is not sufficient to increase astrocytic bFGF- and GFAP-immunoreactivity in Cg2. Consistent with these data, eliminating early maternal experience by removing pups immediately postpartum abolishes the increased bFGF and GFAP protein expression in the cingulate cortex. These results suggest that maternal experience and hormonal state interact to produce astrocytic remodeling in the Cg2. The current results are consistent with a role for the cingulate cortex in maternal responsivity as suggested by early lesion studies in rats and more recent imaging studies in humans.

  11. Experiment K-7-23: Effect of Spaceflight on Level and Function of Immune Cells. Part 1; Immunology Studies

    NASA Technical Reports Server (NTRS)

    Sonnenfeld, G.; Mandel, A.; Konstantinova, I. V.; Berry, W. D.; Taylor, G. R.; Lesnyak, A. T.; Fuchs, B. B.; Rakhmilevich, A. L.

    1994-01-01

    Two different experiments were carried out in this segment of the immunology protocol for samples received from rats flown on Cosmos 2044. Control groups included vivarium, synchronous and antiorthostatically suspended rats. In the first experiment, rat bone marrow cells were examined in Moscow for their response to recombinant murine colony stimulating factor-granulocyte / monocyte (CSF-GM). In the second experiment, rat spleen and bone marrow cells were stained in Moscow with a variety of antibodies directed against cell surface antigenic markers. These cells were preserved and shipped to the United States for analysis on a flow cytometer. The results of the studies indicated that bone marrow cells from flown and suspended rats showed a decreased response to CSF-GM as compared to bone marrow cells from control rats. Spleen cells from flown rats showed increased percentages of suppressor-cytotoxic-T and helper-T cells amongst the entire cell population. Bone marrow cells showed an increase in the percentage of helper-T cells in the myelogenous population and increased percentages of anti-asialo GM-1 bearing, interleukin-2 receptor bearing, pan-T and helper-T cells in the lymphocytic population. Cell populations from rats suspended antiorthostatically did not follow the same pattern of distribution of leukocytes as cell populations for flown rats. These results are similar, but not identical to, earlier results from Cosmos 1887, and confirm that space flight can have profound effects on immune system components and activities.

  12. Influence of previous experience on resistance training on reliability of one-repetition maximum test.

    PubMed

    Ritti-Dias, Raphael Mendes; Avelar, Ademar; Salvador, Emanuel Péricles; Cyrino, Edilson Serpeloni

    2011-05-01

    The 1-repetition maximum test (1RM) has been widely used to assess maximal strength. However, to improve accuracy in assessing maximal strength, several sessions of the 1RM test are recommended. The aim of this study was to analyze the influence of previous resistance training experience on the reliability of 1RM test. Thirty men were assigned to the following 2 groups according to their previous resistance training experience: no previous resistance training experience (NOEXP) and more than 24 months of resistance training experience (EXP). All subjects performed the 1RM tests in bench press and squat in 4 sessions on distinct days. There was a significant session × group effect in bench press (F = 3.09; p < 0.03) and squat (F = 2.76; p < 0.05) showing that only the NOEXP increased maximal strength between the sessions. Significant increases (p < 0.05) in maximal strength occurred in the NOEXP between session 1 and the other sessions in bench press (session 1 vs. 2 = +3.8%; session 1 vs. 3 = +7.4%; session 1 vs. 4 = +10.1%), and squat (session 1 vs. 2 = +7.6%; session 1 vs. 3 = +10.1%; session 1 vs. 4 = +11.2%). Moreover, in bench press, maximal strength in sessions 3 and 4 were significantly higher than in session 2. The results of the present study suggest that the reliability of the 1RM test is influenced by the subject's previous experience in resistance training. Subjects without experience in resistance training require more practice and familiarization and show greater increases in maximal strength between sessions than subjects with previous experience in resistance training.

  13. Transient Atmospheric Circulation Changes in a Grand ensemble of Idealized CO2 Increase Experiments

    NASA Astrophysics Data System (ADS)

    Karpechko, A.; Manzini, E.; Kornblueh, L.

    2017-12-01

    The yearly evolution with increasing forcing of the large-scale atmospheric circulation is examined in a 68-member ensemble of 1pctCO2 scenario experiments performed with the MPI-ESM model. Each member of the experiment ensemble is integrated for 155 years, from initial conditions taken from a 2000-yr long pre-industrial control climate experiment. The 1pctCO2 scenario experiments are conducted following the protocol of including as external forcing only a CO2 concentration increase at 1%/year, till quadrupling of CO2 concentrations. MPI-ESM is the Max-Planck-Institute Earth System Model (including coupling between the atmosphere, ocean and seaice). By averaging over the 68 members (ensemble mean), atmospheric variability is greatly reduced. Thus, it is possible to investigate the sensitivity to the climate state of the atmospheric response to CO2 doubling. Indicators of global change show the expected monotonic evolution with increasing CO2 and a weak dependence of the thermodynamical response to CO2 doubling on the climate state. The surface climate response of the atmospheric circulation, diagnosed for instance by the pressure at sea level, and the eddy-driven jet response show instead a marked dependence to the climate state, for the Northern winter season. We find that as the CO2 concentration increases above doubling, Northern winter trends in some indicators of atmospheric circulation changes decrease or even reverse, posing the question on what are the causes of this nonlinear behavior. The investigation of the role of stationary waves, the meridional overturning circulation, the decrease in Arctic sea ice and the stratospheric vortex points to the latter as a plausible cause of such nonlinear response.

  14. Effects of the wood extractive betulinol and 17beta-oestradiol on reproduction in zebrafish, Danio rerio (Hamilton)--complications due to a bacterial infection.

    PubMed

    Christianson-Heiska, I; Wahteristo, P; Kastilan, E-L; Bergelin, E; Bylund, G; Isomaa, B

    2004-05-01

    Zebrafish were exposed to the wood extractive betulinol (5 microg L(-1)) and to 17beta-oestradiol (E2, 0.27 microg L(-1)) for 8 weeks in an attempt to study the possible endocrine-disrupting activity of betulinol. Females exposed to betulinol showed increased spawning intensity, while males exposed to betulinol and E2 had increased incidences of structural alterations in the testes. However, histological examination of the fish revealed that they were infected by acid-fast bacteria suspected to be Mycobacterium sp. despite a careful examination of their health state prior to the onset of the experiment. Fish exposed to betulinol and E2 showed more serious consequences of the bacterial infection than control fish indicating that the test chemicals had weakened the immune defence of the fish. When the exposure was repeated with healthy fish, an increase in the proportion of spermatogonia was seen in the testes of betulinol-treated males. A similar alteration, although not statistically significant, was also seen in the first experiment. However, no increase in the incidences of structural alterations in the testes was seen in betulinol- and E2-treated fish in the second experiment. Our study indicates that betulinol might have an endocrine-disrupting effect in zebrafish, but the increase in incidences of structural alterations in the testes might have been caused by a synergistic action between the test compounds and the bacterial infection. Our study stresses the importance of carefully checking the health of experimental fish, not only prior to the onset of an experiment but also upon termination of the experiment, in order to avoid misinterpretation of the results.

  15. Anatomical knowledge gain through a clay-modeling exercise compared to live and video observations.

    PubMed

    Kooloos, Jan G M; Schepens-Franke, Annelieke N; Bergman, Esther M; Donders, Rogier A R T; Vorstenbosch, Marc A T M

    2014-01-01

    Clay modeling is increasingly used as a teaching method other than dissection. The haptic experience during clay modeling is supposed to correspond to the learning effect of manipulations during exercises in the dissection room involving tissues and organs. We questioned this assumption in two pretest-post-test experiments. In these experiments, the learning effects of clay modeling were compared to either live observations (Experiment I) or video observations (Experiment II) of the clay-modeling exercise. The effects of learning were measured with multiple choice questions, extended matching questions, and recognition of structures on illustrations of cross-sections. Analysis of covariance with pretest scores as the covariate was used to elaborate the results. Experiment I showed a significantly higher post-test score for the observers, whereas Experiment II showed a significantly higher post-test score for the clay modelers. This study shows that (1) students who perform clay-modeling exercises show less gain in anatomical knowledge than students who attentively observe the same exercise being carried out and (2) performing a clay-modeling exercise is better in anatomical knowledge gain compared to the study of a video of the recorded exercise. The most important learning effect seems to be the engagement in the exercise, focusing attention and stimulating time on task. © 2014 American Association of Anatomists.

  16. The demand for physician services. Evidence from a natural experiment.

    PubMed

    Cockx, Bart; Brasseur, Carine

    2003-11-01

    This study exploits a natural experiment in Belgium to estimate the effect of copayment increases on the demand for physician services. It shows how a differences-in-differences (DD) estimator of the price effects can be decomposed into effects induced by the common average proportional price increase (income effects) and by the change in relative prices (substitution effects). The price elasticity of a uniform proportional price increase is relatively small (-0.13 for men and -0.03 for women). Substitution effects are large, especially for women, but imprecisely estimated. Despite the substantial price increases, the efficiency gain of the reform, if any, is modest.

  17. Are Face and Object Recognition Independent? A Neurocomputational Modeling Exploration.

    PubMed

    Wang, Panqu; Gauthier, Isabel; Cottrell, Garrison

    2016-04-01

    Are face and object recognition abilities independent? Although it is commonly believed that they are, Gauthier et al. [Gauthier, I., McGugin, R. W., Richler, J. J., Herzmann, G., Speegle, M., & VanGulick, A. E. Experience moderates overlap between object and face recognition, suggesting a common ability. Journal of Vision, 14, 7, 2014] recently showed that these abilities become more correlated as experience with nonface categories increases. They argued that there is a single underlying visual ability, v, that is expressed in performance with both face and nonface categories as experience grows. Using the Cambridge Face Memory Test and the Vanderbilt Expertise Test, they showed that the shared variance between Cambridge Face Memory Test and Vanderbilt Expertise Test performance increases monotonically as experience increases. Here, we address why a shared resource across different visual domains does not lead to competition and to an inverse correlation in abilities? We explain this conundrum using our neurocomputational model of face and object processing ["The Model", TM, Cottrell, G. W., & Hsiao, J. H. Neurocomputational models of face processing. In A. J. Calder, G. Rhodes, M. Johnson, & J. Haxby (Eds.), The Oxford handbook of face perception. Oxford, UK: Oxford University Press, 2011]. We model the domain general ability v as the available computational resources (number of hidden units) in the mapping from input to label and experience as the frequency of individual exemplars in an object category appearing during network training. Our results show that, as in the behavioral data, the correlation between subordinate level face and object recognition accuracy increases as experience grows. We suggest that different domains do not compete for resources because the relevant features are shared between faces and objects. The essential power of experience is to generate a "spreading transform" for faces (separating them in representational space) that generalizes to objects that must be individuated. Interestingly, when the task of the network is basic level categorization, no increase in the correlation between domains is observed. Hence, our model predicts that it is the type of experience that matters and that the source of the correlation is in the fusiform face area, rather than in cortical areas that subserve basic level categorization. This result is consistent with our previous modeling elucidating why the FFA is recruited for novel domains of expertise [Tong, M. H., Joyce, C. A., & Cottrell, G. W. Why is the fusiform face area recruited for novel categories of expertise? A neurocomputational investigation. Brain Research, 1202, 14-24, 2008].

  18. Understanding the Sensitivity of a GCM Simulation of Amazonian Deforestation to the Specification of Vegetation and Soil Characteristics.

    NASA Astrophysics Data System (ADS)

    Lean, J.; Rowntree, P. R.

    1997-06-01

    The experiment reported on here presents a realistic portrayal of Amazonian deforestation that uses measurements of vegetation characteristics, taken as part of the Anglo-Brazilian Amazonian Climate Observation Study field campaigns, to define the forest and replacement pasture vegetation in the Hadley Centre GCM. The duration of the main experiment (10 yr) leads to greater confidence in assessing regional changes than in previous shorter experiments.Complete removal of the Amazonian forest produced area-mean changes that resemble earlier experiments with decreases in evaporation of 0.76 mm day1 (18%) and rainfall of 0.27 mm day1 (4%) and a rise in surface temperature of 2.3°C. However, the relative changes in magnitude indicate that increased moisture convergence partly compensates for the reduced evaporation, in contrast to many previous deforestation experiments. Results also showed large regional variations in the change in annual mean rainfall over South America, with widespread decreases over most of the deforested area and increases near the Andes.A better understanding of the mechanisms responsible for the final deforested climate has been gained by carrying out additional experiments that examine the response to separate changes in roughness and albedo. Increased albedo resulted in widespread significant decreases in rainfall due to less moisture convergence and ascent. The response to reduced roughness is more complex but of comparable importance; in this experiment it was dominated by an increase in low-level wind speeds resulting in decreased moisture convergence and rainfall near the upwind edge of the area and the opposite near the downwind boundary where the increased flow meets the Andes.In the standard deforestation scenario all vegetation parameters were modified together with one soil parameter-the maximum infiltration rate, which is reduced to represent the observed compaction of soil following deforestation. Results from a further experiment, in which the maximum infiltration rate was left unchanged, showed much smaller reductions in evaporation of 0.3 mm day1 (7%) and indicated that the predicted regional changes in rainfall and evaporation were very sensitive to this parameter.

  19. The role of fear in delusions of the paranormal.

    PubMed

    Lange, R; Houran, J

    1999-03-01

    Based on an extended process model derived from attribution theory, we hypothesized that pervasive and persistent delusions of the paranormal are characterized by the existence of a positive (self-reinforcing), rather than a negative (self-correcting), feedback loop involving paranormal beliefs, fears, and experiences, as moderated by gender and tolerance of ambiguity. A cross-cultural sample of "international" students who reported poltergeist-like experiences showing high fear of the paranormal was identified. As in earlier research, path analysis showed statistically significant and positive effects of belief on experience and/or fear on belief. However, paranormal experience now had a positive effect on fear as well. Thus, as predicted, increased fear removes the option of neutralizing ambiguous events by labeling them as "paranormal." Although female subjects showed significantly greater fear of the paranormal than male subjects, there is no evidence that the nature of the delusional process is gender specific.

  20. Auditory recognition of familiar and unfamiliar subjects with wind turbine noise.

    PubMed

    Maffei, Luigi; Masullo, Massimiliano; Gabriele, Maria Di; Votsi, Nefta-Eleftheria P; Pantis, John D; Senese, Vincenzo Paolo

    2015-04-17

    Considering the wide growth of the wind turbine market over the last decade as well as their increasing power size, more and more potential conflicts have arisen in society due to the noise radiated by these plants. Our goal was to determine whether the annoyance caused by wind farms is related to aspects other than noise. To accomplish this, an auditory experiment on the recognition of wind turbine noise was conducted to people with long experience of wind turbine noise exposure and to people with no previous experience to this type of noise source. Our findings demonstrated that the trend of the auditory recognition is the same for the two examined groups, as far as the increase of the distance and the decrease of the values of sound equivalent levels and loudness are concerned. Significant differences between the two groups were observed as the distance increases. People with wind turbine noise experience showed a higher tendency to report false alarms than people without experience.

  1. Auditory recognition of familiar and unfamiliar subjects with wind turbine noise

    PubMed Central

    Maffei, Luigi; Masullo, Massimiliano; Di Gabriele, Maria; Votsi, Nefta-Eleftheria P.; Pantis, John D.; Senese, Vincenzo Paolo

    2015-01-01

    Considering the wide growth of the wind turbine market over the last decade as well as their increasing power size, more and more potential conflicts have arisen in society due to the noise radiated by these plants. Our goal was to determine whether the annoyance caused by wind farms is related to aspects other than noise. To accomplish this, an auditory experiment on the recognition of wind turbine noise was conducted to people with long experience of wind turbine noise exposure and to people with no previous experience to this type of noise source. Our findings demonstrated that the trend of the auditory recognition is the same for the two examined groups, as far as the increase of the distance and the decrease of the values of sound equivalent levels and loudness are concerned. Significant differences between the two groups were observed as the distance increases. People with wind turbine noise experience showed a higher tendency to report false alarms than people without experience. PMID:25898408

  2. Purification and identification of a polysaccharide from medicinal mushroom Amauroderma rude with immunomodulatory activity and inhibitory effect on tumor growth.

    PubMed

    Pan, Honghui; Han, Yuanyuan; Huang, Jiguo; Yu, Xiongtao; Jiao, Chunwei; Yang, Xiaobing; Dhaliwal, Preet; Xie, Yizhen; Yang, Burton B

    2015-07-10

    Medicinal mushrooms in recent years have been the subject of many experiments searching for anticancer properties. We previously screened thirteen mushrooms for their potential in inhibiting tumor growth, and found that the water extract of Amauroderma rude exerted the highest activity. Previous studies have shown that the polysaccharides contained in the water extract were responsible for the anticancer properties. This study was designed to explore the potential effects of the polysaccharides on immune regulation and tumor growth. Using the crude Amauroderma rude extract, in vitro experiments showed that the capacities of spleen lymphocytes, macrophages, and natural killer cells were all increased. In vivo experiments showed that the extract increased macrophage metabolism, lymphocyte proliferation, and antibody production. In addition, the partially purified product stimulated the secretion of cytokines in vitro, and in vivo. Overall, the extract decreased tumor growth rates. Lastly, the active compound was purified and identified as polysaccharide F212. Most importantly, the purified polysaccharide had the highest activity in increasing lymphocyte proliferation. In summary, this molecule may serve as a lead compound for drug development.

  3. Glucocorticoid exposure alters the pathogenesis of Theiler’s murine encephalomyelitis virus during acute infection

    PubMed Central

    Young, Erin E.; Prentice, Thomas W.; Satterlee, Danielle; McCullough, Heath; Sieve, Amy N.; Johnson, Robin R.; Welsh, Thomas H.; Welsh, C. Jane R.; Meagher, Mary W.

    2008-01-01

    Previous research has shown that chronic restraint stress exacerbates Theiler’s virus infection, a murine model for CNS inflammation and multiple sclerosis. The current set of experiments was designed to evaluate the potential role of glucocorticoids in the deleterious effects of restraint stress on acute CNS inflammatory disease. Exposure to chronic restraint stress resulted in elevated levels of corticosterone as well as increased clinical scores and weight loss (Experiment 1). In addition, corticosterone administration alone exacerbated behavioral signs of TMEV-induced sickness (i.e. decreased body weight, increased symptoms of encephalitis, and increased mortality) and reduced inflammation in the CNS (Experiment 2). Infected subjects receiving exogenous corticosterone showed exacerbation of acute phase measures of sickness and severe mortality as well as decreased viral clearance from CNS (Experiment 3). These findings indicate that corticosterone exposure alone is sufficient to exacerbate acute CNS inflammatory disease. PMID:18538803

  4. Lifelong learning skills: how experienced are students when they enter medical school?

    PubMed

    Whittle, Sue R; Murdoch-Eaton, Deborah G

    2004-09-01

    Widening participation initiatives together with changes in school curricula in England may broaden the range of lifelong learning skills experience of new undergraduates. This project examines the experience levels of current students, as a comparative baseline. First-year medical students completed a questionnaire on arrival, investigating their practice of 31 skills during the previous two years. Responses show that most students have regularly practised transferable skills. However, significant numbers report little experience, particularly in IT skills such as email, using the Internet, spreadsheets and databases. Some remain unfamiliar with word processing. Library research, essay writing and oral presentation are also rarely practised by substantial numbers. One-third of students lack experience of evaluating their own strengths and weaknesses. Current students already show diversity of experience in skills on arrival at medical school. Changes in the near future may increase this range of experience further, and necessitate changes to undergraduate courses.

  5. Sexual Experience Modulates Neuronal Activity in Male Japanese Quail

    PubMed Central

    Can, Adem; Domjan, Michael; Delville, Yvon

    2008-01-01

    After an initial increase, repeated exposure to a particular stimulus or familiarity with an event results in lower immediate early gene expression levels in relevant brain structures. We predicted that similar effects would occur in Japanese quail after repeated sexual experience within brain areas involved in sexual behavior, namely, the medial preoptic nucleus (POM), the bed nucleus of stria terminalis (BST), and the nucleus taeniae of the amygdala (TnA), an avian homolog of medial amygdala. High experience subjects copulated with a female once on each of 16 consecutive days, whereas low experience subjects were allowed to copulate either once or twice. Control subjects were never exposed to a female. High experience subjects were faster to initiate sexual interaction, performed more cloacal contacts, and completed each cloacal contact faster than low experience subjects. Low experience subjects showed an increase in egr-1 (ZENK) expression, an immediate early gene product used as marker of neural activation in birds, in the areas of interest. In contrast, in high experience animals, egr-1 expression in the POM, BST and the periaqueductal gray (PAG) was not different than the level of expression in unmated controls. These results show that experience modulates the level of immediate early gene expression in the case of sexual behavior. Our results also indicate that immediate early gene expression in specific brain areas is not necessarily related to behavioral output, but depends on the behavioral history of the subjects. PMID:17826778

  6. Methylphenidate improves performance on the radial arm maze in periadolescent rats

    PubMed Central

    Dow-Edwards, Diana L.; Weedon, Jeremy C.; Hellmann, Esther

    2008-01-01

    Methylphenidate (Ritalin; MPD) is one of the most commonly prescribed drugs in childhood and adolescence and many clinical studies have documented its efficacy. Due to the limitations of conducting invasive research in humans, animal models can be beneficial for studying drug effects. However, few animal studies have demonstrated the effects of methylphenidate on cognitive processes. The objective of this study was to find a dose of methylphenidate that was effective in improving performance on a spatial working memory cognitive task when administered orally to periadolescent rats. Therefore, we dosed subjects with methylphenidate at 1 or 3 mg/kg/day via gastric intubation from postnatal day 22 to 59 and assessed the effects of the drug on performance on the radial arm maze each day. To enhance performance overall, a second experiment was conducted where the subjects were moderately food restricted (to 90% of the free-feeding weight). Results of Experiment 1 show that during the first week of testing only the 3mg/kg MPD-treated males showed improved performance (entries prior to repeated entry) when ad-lib fed and housed in pairs while the same dose significantly improved performance in both males and females under conditions of food-restriction and individual housing in Experiment 2. MPD also produced a pattern of increased errors and arms entered during the first week, especially in Experiment 2. MPD increased locomotor activity when tested at postnatal day 60 in both experiments. The data suggest that 3mg/kg oral methylphenidate improves performance on a spatial cognitive task only early in treatment in the rat. While males show improvement under conditions of both high and low motivation, females only show MPD effects when highly motivated. Hypothetically, methylphenidate may improve radial arm maze performance through increased attention and improved spatial working memory and/or alterations in locomotion, reactivity to novelty or anxiety. Regardless, the study supports the utility of the rat as a suitable model to examine the effects of low dose oral MPD. PMID:18538539

  7. Active Dentate Granule Cells Encode Experience to Promote the Addition of Adult-Born Hippocampal Neurons

    PubMed Central

    Kirschen, Gregory W.; Shen, Jia; Wang, Jia; Man, Guoming; Wu, Song

    2017-01-01

    The continuous addition of new dentate granule cells (DGCs), which is regulated exquisitely by brain activity, renders the hippocampus plastic. However, how neural circuits encode experiences to affect the addition of adult-born neurons remains unknown. Here, we used endoscopic Ca2+ imaging to track the real-time activity of individual DGCs in freely behaving mice. For the first time, we found that active DGCs responded to a novel experience by increasing their Ca2+ event frequency preferentially. This elevated activity, which we found to be associated with object exploration, returned to baseline by 1 h in the same environment, but could be dishabituated via introduction to a novel environment. To transition seamlessly between environments, we next established a freely controllable virtual reality system for unrestrained mice. We again observed increased firing of active neurons in a virtual enriched environment. Interestingly, multiple novel virtual experiences increased the number of newborn neurons accumulatively compared with a single experience. Finally, optogenetic silencing of existing DGCs during novel environmental exploration perturbed experience-induced neuronal addition. Our study shows that the adult brain conveys novel, enriched experiences to increase the addition of adult-born hippocampal neurons by increasing the firing of active DGCs. SIGNIFICANCE STATEMENT Adult brains are constantly reshaping themselves from synapses to circuits as we encounter novel experiences from moment to moment. Importantly, this reshaping includes the addition of newborn hippocampal neurons. However, it remains largely unknown how our circuits encode experience-induced brain activity to govern the addition of new hippocampal neurons. By coupling in vivo Ca2+ imaging of dentate granule neurons with a novel, unrestrained virtual reality system for rodents, we discovered that a new experience increased firing of active dentate granule neurons rapidly and robustly. Exploration in multiple novel virtual environments, compared with a single environment, promoted dentate activation and enhanced the addition of new hippocampal neurons accumulatively. Finally, silencing this activation optogenetically during novel experiences perturbed experience-induced neuronal addition. PMID:28373391

  8. Role of 5-aminolevulinic acid-conjugated gold nanoparticles for photodynamic therapy of cancer

    NASA Astrophysics Data System (ADS)

    Zhang, Zhenxi; Wang, Sijia; Xu, Hao; Wang, Bo; Yao, Cuiping

    2015-05-01

    There are three possible mechanisms for 5-aminolevulinic acid (5-ALA) conjugated gold nanoparticles (GNPs) through electrostatic bonding for photodynamic therapy (PDT) of cancer: GNPs delivery function, singlet oxygen generation (SOG) by GNPs irradiated by light, and surface resonance enhancement (SRE) of SOG. Figuring out the exact mechanism is important for further clinical treatment. 5-ALA-GNPs and human chronic myeloid leukemia K562 cells were used to study delivery function and SOG by GNPs. The SRE of SOG enabled by GNPs was explored by protoporphyrin IX (PpIX)-GNPs conjugate through electrostatic bonding. Cell experiments show that the GNPs can improve the efficiency of PDT, which is due to the vehicle effect of GNPs. PpIX-GNPs conjugate experiments demonstrated that SOG can be improved about 2.5 times over PpIX alone. The experiments and theoretical results show that the local field enhancement (LFE) via localized surface plasmon resonance (LSPR) of GNPs is the major role; the LFE was dependent on the irradiation wavelength and the GNP's size. The LFE increased with an increase of the GNP size (2R ≤50 nm). However, the LSPR function of the GNPs was not found in cell experiments. Our study shows that in 5-ALA-conjugated GNPs PDT, the delivery function of GNPs is the major role.

  9. Winning agonistic encounters increases testosterone and androgen receptor expression in Syrian Hamsters

    PubMed Central

    Clinard, Catherine T.; Barnes, Abigail K.; Adler, Samuel G.; Cooper, Matthew A.

    2016-01-01

    Winning aggressive disputes is one of several experiences that can alter responses to future stressful events. We have previously tested dominant and subordinate male Syrian hamsters in a conditioned defeat model and found that dominant individuals show less change in behavior following social defeat stress compared to subordinates and controls, indicating a reduced conditioned defeat response. Resistance to the effects of social defeat in dominants is experience-dependent and requires the maintenance of dominance relationships for 14 days. For this study we investigated whether winning aggressive interactions increases plasma testosterone and whether repeatedly winning increases androgen receptor expression. First, male hamsters were paired in daily 10-min aggressive encounters and blood samples were collected immediately before and 15-min and 30-min after the formation of dominance relationships. Dominants showed an increase in plasma testosterone at 15-min post-interaction compared to their pre-interaction baseline, whereas subordinates and controls showed no change in plasma testosterone. Secondly, we investigated whether 14 days of dominant social status increased androgen or estrogen alpha-receptor immunoreactivity in brain regions that regulate the conditioned defeat response. Dominants showed more androgen, but not estrogen alpha, receptor immuno-positive cells in the dorsal medial amygdala (dMeA) and ventral lateral septum (vLS) compared to subordinates and controls. Finally, we showed that one day of dominant social status was insufficient to increase androgen receptor immunoreactivity compared to subordinates. These results suggest that elevated testosterone signaling at androgen receptors in the dMeA and vLS might contribute to the reduced conditioned defeat response exhibited by dominant hamsters. PMID:27619945

  10. An analysis of the Lorenz energy cycle for conditions of low, middle and high CO2 concentrations based on the RCP2.6, RCP4.5 and RCP8.5

    NASA Astrophysics Data System (ADS)

    Veiga, J. A.; Ambrizzi, T.

    2013-05-01

    The energetic analysis in this study takes account the new set of scenarios forcing experiments: RCP85, RCP45, RCP26. The model used in this study pertains to the fifth Coupled Model Intercomparison Project (CMIP5). The results show a decrease in the most of energy terms of the Lorenz energetics for the global domain. The reduction of the values in the energy cycle is clear and is independent of the CO2 emission scenario. However, the strongest reduction is related to the highest radiative forcing experiment the RCP85. As an inverse behavior the results show an increase in CK, KZ and KE components of the energy cycle. Similar reduction in the energetics intensity is observed for the SH domain, with RCP85 emission scenario provoking the most intense decrease in the energy terms. However, for this scenario the energetics projection indicates an increase in KZ of 24.6%, which is higher than for global (21.56%) and for the NH (9.36%) domains. The increase of KZ for all domains is attributed to the increase in CK, which in this case acts as a source of energy for KZ, and to the efficiency factor, which is defined as the rate between conversion and generation. The NH energetics suffer changes in the energy cycle as well. The results showed a reduction in CE for all scenarios, however KE suffer low rate of increase relative for the historical experiment.

  11. Crayfish behavioral changes with CO2

    NASA Astrophysics Data System (ADS)

    Ellis, J.

    2017-12-01

    Changes in carbon dioxide (CO2) could have a major impact on aquatic life. We examined the effects of different levels of CO2 on the behavior of crayfish. The shelter treatments showed that crayfish became less active with increased CO2. The predator treatments showed that crayfish became more aggressive with increased CO2. From these experiments, we conclude that the roles of crayfish in the ecosystem could change.

  12. Monomolecular Silane Coatings on Magnesium/Aluminium Fuels

    DTIC Science & Technology

    1991-07-01

    iii SUMMARY The aim of this project was to investigate the curing reaction between CTBN and magnesium/aluminium ailoy surfaces. A dispersion of...performing rheoloqacai experiments with these coated magnesium particles and CTBN . Surface analysis ot the alloys show a nigh percentage of magnesium...Rheoloq’cai analysis of these alloys dispersed 40% w/w in CTBN show increasing rates of change in viscosity with time for each alloy with increasing nominal

  13. An Analysis of Response-Contingent Learning Experiences for Young Children.

    ERIC Educational Resources Information Center

    Hanson, Marci J.; Hanline, Mary Frances

    1985-01-01

    Three children with severe and multiple disabilities (8-25 months old) were provided contingent learning experiences via electromechanical apparatus. Results indicated that all three children increased the frequency of the target behavior. The data are equivocal as to whether or not children showed an awareness of the response-contingent feedback.…

  14. Colored Overlays Enhance Visual Perceptual Performance in Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Ludlow, A. K.; Wilkins, A. J.; Heaton, P.

    2008-01-01

    Children with autism spectrum disorders (ASD), together with controls matched for age and ability participated in three experiments that assessed the therapeutic benefit of colored overlays. The findings from the first experiment showed that a significantly greater proportion of children with ASD, than controls, increased reading speed when using…

  15. Steps, Stages, and Structure: Finding Compensatory Order in Scientific Theories

    ERIC Educational Resources Information Center

    Rutjens, Bastiaan T.; van Harreveld, Frenk; van der Pligt, Joop; Kreemers, Loes M.; Noordewier, Marret K.

    2013-01-01

    Stage theories are prominent and controversial in science. One possible reason for their appeal is that they provide order and predictability. Participants in Experiment 1 rated stage theories as more orderly and predictable (but less credible) than continuum theories. In Experiments 2-5, we showed that order threats increase the appeal of stage…

  16. Encouraging Students to Engage with Native Speakers during Study Abroad

    ERIC Educational Resources Information Center

    Cadd, Marc

    2012-01-01

    Students, their parents, and educators trust that a study-abroad experience is the best way to increase linguistic proficiency. The professional literature, however, shows a much more complex picture. Gains in linguistic proficiency appear to depend on variables such as whether the students experience a homestay or dormitory, the length of time…

  17. Teaching into the Heart of Knowing in Online Education: Aesthetics & Pragmatics

    ERIC Educational Resources Information Center

    Chapman, Jocelyn Elizabeth

    2012-01-01

    The purpose of this dissertation is to show how aesthetic experiences and nontrivial conversations are at the heart of learning and can be designed for and practiced online. Aesthetic experiences are moments of acute attention, imbued with meaning (Parrish, 2009). Nontrivial conversations are conversations that increase possibilities for learning…

  18. Teachers' generalized use of delay as a stimulus control procedure to increase language use in handicapped children.

    PubMed Central

    Halle, J W; Baer, D M; Spradlin, J E

    1981-01-01

    In Experiment 1, classroom teachers were taught to delay their offers of help in naturally occurring situations, and thereby to provide additional opportunities for language use by six moderately retarded language-delayed children. The teachers introduced this delay technique in a multiple-baseline design across the six children. As delays were used, child verbal initiations increased. Follow-up assessment showed that teachers were maintaining greater than baseline levels of the delay technique after 10 weeks. Experiment 2 replicated the findings of Experiment 1, and included a more thorough maintenance assessment, while focusing on teachers' generalization of the delay technique. Teachers were found to generalize their use of delay to 56% of their monitored untaught opportunities. The two experiments show that (a) the delay technique is quick to teach and simple to implement, (b) delays do provide opportunities for children to initiate, (c) teachers can generalize their use of delay to novel self-selected situations, and (d) teachers can maintain their use of delays over time. PMID:6460019

  19. Embodied Information in Cognitive Tasks: Haptic Weight Sensations Affect Task Performance and Processing Style

    PubMed Central

    Kaspar, Kai; Vennekötter, Alina

    2015-01-01

    Research in the field of embodied cognition showed that incidental weight sensations influence peoples’ judgments about a variety of issues and objects. Most studies found that heaviness compared to lightness increases the perception of importance, seriousness, and potency. In two experiments, we broadened this scope by investigating the impact of weight sensations on cognitive performance. In Experiment 1, we found that the performance in an anagram task was reduced when participants held a heavy versus a light clipboard in their hands. Reduced performance was accompanied by an increase in the perceived effort. In Experiment 2, a heavy clipboard elicited a specific response heuristic in a two-alternative forced-choice task. Participants showed a significant right side bias when holding a heavy clipboard in their hands. After the task, participants in the heavy clipboard condition reported to be more frustrated than participants in the light clipboard condition. In both experiments, we did not find evidence for mediated effects that had been proposed by previous literature. Overall, the results indicate that weight effects go beyond judgment formation and highlight new avenues for future research. PMID:26421084

  20. What we think we learn from watching others: the moderating role of ability on perceptions of learning from observation.

    PubMed

    Hodges, Nicola J; Coppola, Thomas

    2015-07-01

    Despite increased interest in the processes guiding action observation and observational learning, we know little about what people think they learn from watching, how well perceptions of learning marry with actual ability and how ability perceptions develop across multiple observation trials. Based on common coding ideas, we would think that ability and perceptions of ability from watching should be well matched. We conducted two studies to answer these questions that involved repeated observation of a 2-ball juggling task. After each video observation, observers judged if they could perform the skill and gave a confidence score (0-100%). In Experiment 1, an Observe-only group was compared to an Observe + Physical practice and No-practice group. Both observer groups showed a better physical approximation of the juggling action after practice and in retention and their confidence increased in a linear fashion. Confidence showed a small, yet significant relationship to actual success. In Experiment 2, we limited physical practice to 5 attempts (across 50 observation trials). In general, people who had high perceptions of ability following a demonstration were overconfident, whereas those with lower perceptions of ability were accurate in their assessments. Confidence generally increased across practice, particularly for trials following observation rather than physical practice. We conclude that while perceptions of ability and actual ability show congruence across trials and individuals, observational practice increases people's confidence in their ability to perform a skill, even despite physical experiences to the contrary.

  1. Long-term priming of neighbours biases the word recognition process: evidence from a lexical decision task.

    PubMed

    Wagenmakers, Eric-Jan; Raaijmakers, Jeroen G W

    2006-12-01

    The role of orthographically similar words (i.e., neighbours) in the word recognition process has been studied extensively using short-term priming paradigms (e.g., Colombo, 1986). Here we demonstrate that long-term effects of neighbour priming can also be obtained. Experiment 1 showed that prior study of a neighbour (e.g., TANGO) increased later lexical decision performance for similar words (e.g., MANGO), but decreased performance for similar pseudowords (e.g., LANGO). Experiment 2 replicated this bias effect and showed that the increase in lexical decision performance due to neighbour priming is selectively due to words from a relatively sparse neighbourhood. Explanations of the bias effect in terms of lexical activation and episodic memory retrieval are discussed.

  2. [Nutrient use efficiency and yield-increasing effect of single basal application of rice specific controlled release fertilizer].

    PubMed

    Chen, Jiansheng; Xu, Peizhi; Tang, Shuanhu; Zhang, Fabao; Xie, Chunsheng

    2005-10-01

    A series of pot and field experiments and field demonstrations showed that in comparing with the commonly used specific-fertilizers containing same amounts of nutrients, single basal application of rice-specific controlled release fertilizer could increase the use efficiency of N and P by 12.2% - 22.7% and 7.0% - 35.0%, respectively in pot experiment, and the use efficiency of N by 17.1% in field experiment. In 167 field demonstrations successively conducted for 3 years in various rice production areas of Guangdong Province, single basal application of the fertilizer saved the application rate of N and P by 22.1% and 21.8%, respectively, and increased the yield by 8.2%, compared with normal split fertilization.

  3. [Effect of Xinling Wan in treatment of stable angina pectoris: a randomized, double-blinded, placebo parallel-controlled, multicenter trial].

    PubMed

    Gao, Jian-Wei; Gao, Xue-Min; Zou, Ting; Zhao, Tian-Meng; Wang, Dong-Hua; Wu, Zong-Gui; Ren, Chang-Jie; Wang, Xing; Geng, Nai-Zhi; Zhao, Ming-Jun; Liang, Qiu-Ming; Feng, Xing; Yang, Bai-Song; Shi, Jun-Ling; Hua, Qi

    2018-03-01

    To evaluate the effectiveness and safety of Xinling Wan on patients with stable angina pectoris, a randomized, double-blinded, placebo parallel-controlled, multicenter clinical trial was conducted. A total of 232 subjects were enrolled and randomly divided into experiment group and placebo group. The experiment group was treated with Xinling Wan (two pills each time, three times daily) for 4 weeks, and the placebo group was treated with placebo. The effectiveness evaluation showed that Xinling Wan could significantly increase the total duration of treadmill exercise among patients with stable angina pectoris. FAS analysis showed that the difference value of the total exercise duration was between experiment group (72.11±139.32) s and placebo group (31.25±108.32) s. Xinling Wan could remarkably increase the total effective rate of angina pectoris symptom score, and the analysis showed that the total effective rate was 78.95% in experiment group and 42.61% in placebo group. The reduction of nitroglycerin dose was (2.45±2.41) tablets in experiment group and (0.50±2.24) tablets in placebo group on the basis of FAS analysis. The decrease of symptom integral was (4.68±3.49) in experiment group and (3.19±3.31) in placebo group based on FAS analysis. Besides, Xinling Wan could decrease the weekly attack time and the duration of angina pectoris. PPS analysis results were similar to those of FAS analysis. In conclusion, Xinling Wan has an obvious therapeutic effect in treating stable angina pectoris, with a good safety and a low incidence of adverse event and adverse reaction in experiment group. Copyright© by the Chinese Pharmaceutical Association.

  4. Improving Power Density of Free-Piston Stirling Engines

    NASA Technical Reports Server (NTRS)

    Briggs, Maxwell H.; Prahl, Joseph M.; Loparo, Kenneth A.

    2016-01-01

    Analyses and experiments demonstrate the potential benefits of optimizing piston and displacer motion in a free-piston Stirling Engine. Isothermal analysis shows the theoretical limits of power density improvement due to ideal motion in ideal Stirling engines. More realistic models based on nodal analysis show that ideal piston and displacer waveforms are not optimal, often producing less power than engines that use sinusoidal piston and displacer motion. Constrained optimization using nodal analysis predicts that Stirling engine power density can be increased by as much as 58 percent using optimized higher harmonic piston and displacer motion. An experiment is conducted in which an engine designed for sinusoidal motion is forced to operate with both second and third harmonics, resulting in a piston power increase of as much as 14 percent. Analytical predictions are compared to experimental data and show close agreement with indirect thermodynamic power calculations, but poor agreement with direct electrical power measurements.

  5. Improving Power Density of Free-Piston Stirling Engines

    NASA Technical Reports Server (NTRS)

    Briggs, Maxwell H.; Prahl, Joseph; Loparo, Kenneth

    2016-01-01

    Analyses and experiments demonstrate the potential benefits of optimizing piston and displacer motion in a free piston Stirling Engine. Isothermal analysis shows the theoretical limits of power density improvement due to ideal motion in ideal Stirling engines. More realistic models based on nodal analysis show that ideal piston and displacer waveforms are not optimal, often producing less power than engines that use sinusoidal piston and displacer motion. Constrained optimization using nodal analysis predicts that Stirling engine power density can be increased by as much as 58 using optimized higher harmonic piston and displacer motion. An experiment is conducted in which an engine designed for sinusoidal motion is forced to operate with both second and third harmonics, resulting in a maximum piston power increase of 14. Analytical predictions are compared to experimental data showing close agreement with indirect thermodynamic power calculations, but poor agreement with direct electrical power measurements.

  6. Improving Free-Piston Stirling Engine Power Density

    NASA Technical Reports Server (NTRS)

    Briggs, Maxwell H.

    2016-01-01

    Analyses and experiments demonstrate the potential benefits of optimizing piston and displacer motion in a free piston Stirling Engine. Isothermal analysis shows the theoretical limits of power density improvement due to ideal motion in ideal Stirling engines. More realistic models based on nodal analysis show that ideal piston and displacer waveforms are not optimal, often producing less power than engines that use sinusoidal piston and displacer motion. Constrained optimization using nodal analysis predicts that Stirling engine power density can be increased by as much as 58% using optimized higher harmonic piston and displacer motion. An experiment is conducted in which an engine designed for sinusoidal motion is forced to operate with both second and third harmonics, resulting in a maximum piston power increase of 14%. Analytical predictions are compared to experimental data showing close agreement with indirect thermodynamic power calculations, but poor agreement with direct electrical power measurements.

  7. Interacting hands: the role of attention for the joint Simon effect

    PubMed Central

    Liepelt, Roman

    2014-01-01

    Recent research in monkeys and humans has shown that the presence of the hands near an object enhances spatial processing for objects presented near the hand. This study aimed to test the effect of hand position on the joint Simon effect. In Experiment 1, two human co-actors shared a Simon task while placing their response hands either near the objects appearing on the monitor or away from the monitor. Experiment 2 varied each co-actor’s hand position independently. Experiment 3 tested whether enhanced spatial processing for objects presented near the hand is obtained when replacing one of the two co-actors by a non-human event-producing rubber hand. Experiment 1 provided evidence for a Simon effect. Hand position significantly modulated the size of the Simon effect in the joint Simon task showing an increased Simon effect when the hands of both actors were located near the objects on the monitor, than when they were located away from the monitor. Experiment 2 replicated this finding showing an increased Simon effect when the actor’s hand was located near the objects on the monitor, but only when the co-actor also produced action events in spatial reference. A similar hand position effect was observed in Experiment 3 when a non-human rubber hand replaced the human co-actor. These findings suggest that external action events that are produced in spatial reference bias the distribution of attention to the area near the hand. This strengthens the weight of the spatial response codes (referential coding) and hence increases the joint Simon effect. PMID:25566140

  8. Can a near win kindle motivation? The impact of nearly winning on motivation for unrelated rewards.

    PubMed

    Wadhwa, Monica; Kim, JeeHye Christine

    2015-06-01

    Common intuition and research suggest that winning is more motivating than losing. However, we propose that just failing to obtain a reward (i.e., nearly winning it) in one task leads to broader, positive motivational effects on subsequent unrelated tasks relative to clearly losing or actually obtaining the reward. We manipulated a near-win experience using a game app in Experiments 1 through 3 and a lottery in Experiment 4. Our findings showed that nearly winning in one task subsequently led participants to walk faster to get to a chocolate bar (Experiment 1), salivate more for money (Experiment 2), and increase their effort to earn money in a card-sorting task (Experiment 3). A field study (Experiment 4) demonstrated that nearly winning led people to subsequently spend more money on desirable consumer products. Finally, our findings showed that when the activated motivational state was dampened in an intervening task, the nearly-winning effect was attenuated. © The Author(s) 2015.

  9. A comprehensive test of evolutionarily increased competitive ability in a highly invasive plant species

    PubMed Central

    Joshi, Srijana; Gruntman, Michal; Bilton, Mark; Seifan, Merav; Tielbörger, Katja

    2014-01-01

    Background and Aims A common hypothesis to explain plants' invasive success is that release from natural enemies in the introduced range selects for reduced allocation to resistance traits and a subsequent increase in resources available for growth and competitive ability (evolution of increased competitive ability, EICA). However, studies that have investigated this hypothesis have been incomplete as they either did not test for all aspects of competitive ability or did not select appropriate competitors. Methods Here, the prediction of increased competitive ability was examined with the invasive plant Lythrum salicaria (purple loosestrife) in a set of common-garden experiments that addressed these aspects by carefully distinguishing between competitive effect and response of invasive and native plants, and by using both intraspecific and interspecific competition settings with a highly vigorous neighbour, Urtica dioica (stinging nettle), which occurs in both ranges. Key Results While the intraspecific competition results showed no differences in competitive effect or response between native and invasive plants, the interspecific competition experiment revealed greater competitive response and effect of invasive plants in both biomass and seed production. Conclusions The use of both intra- and interspecific competition experiments in this study revealed opposing results. While the first experiment refutes the EICA hypothesis, the second shows strong support for it, suggesting evolutionarily increased competitive ability in invasive populations of L. salicaria. It is suggested that the use of naturally co-occurring heterospecifics, rather than conspecifics, may provide a better evaluation of the possible evolutionary shift towards greater competitive ability. PMID:25301818

  10. Design, synthesis, and characterization of lightly sulfonated multigraft acrylate-based copolymer superelastomers

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

    Misichronis, Konstantinos; Wang, Weiyu; Cheng, Shiwang

    2018-01-29

    Multigraft copolymer superelastomers consisting of a poly(n-butyl acrylate) backbone and polystyrene side chains were synthesized and the viscoelastic properties of the non-sulfonated and sulfonated final materials were investigated using extensional rheology (SER3). The non-linear viscoelastic experiments revealed significantly increased true stresses (up to 10 times higher) after sulfonating only 2–3% of the copolymer while the materials maintained high elongation (<700%). The linear viscoelastic experiments showed that the storage and loss modulus are increased by sulfonation and that the copolymers can be readily tuned and further improved by increasing the number of branching points and the molecular weight of the backbone.more » Here, in this way, we show that by tuning not only the molecular characteristics of the multigraft copolymers but also their architecture and chemical interaction, we can acquire thermoplastic superelastomer materials with desired viscoelastic properties.« less

  11. Persistence of increased adiposity in parenterally fed neonatal pigs

    USDA-ARS?s Scientific Manuscript database

    The nutritional environment during fetal and neonatal life is a key determinant affecting the risk for adult-onset diseases, such as diabetes and obesity. Studies show that preterm infants experience increased risk for glucose intolerance as adolescents and young adults. Preterm infants often receiv...

  12. Direct and Indirect Harassment Experiences and Burnout among Academic Faculty in Japan.

    PubMed

    Takeuchi, Masumi; Nomura, Kyoko; Horie, Saki; Okinaga, Hiroko; Perumalswami, Chithra R; Jagsi, Reshma

    2018-05-01

    The purpose of this study is three-fold: (1) to compare harassment (sexual, gender, and academic harassment both directly and indirectly experienced - i.e. "directly harassed" and "have seen or heard of someone who experienced harassment", respectively) experienced by males and females, (2) to investigate whether such experiences correlate with burnout, and (3) to explore whether social support might mitigate any such relationship between harassment and burnout. This cross-sectional study was conducted at a private university in Japan in February 2014 and is based on a work-life balance survey obtained from 330 academic faculty members. We investigated the association between each of the six subcategories of harassment (direct and indirect forms of each of the three types) and burnout using general linear regression models; we then evaluated interactions between harassment and social support in these models. The prevalence of direct and indirect experiences of harassment was higher in females than in males for all three types of harassment. Males showed higher burnout scores if they had direct experiences of harassment. There were significant interactions between social support and the direct experience of harassment; high social support mitigated the effect size of direct harassment on burnout among males. Females showed higher burnout scores if they had indirect experiences of harassment. However, the same buffering effect of social support on burnout as observed in males was not observed in females. Direct harassment experiences increased the risk of burnout in males, and indirect harassment experiences increased burnout in females.

  13. Now or later? Understanding the etiologic period of suicide

    PubMed Central

    Vandoros, Sotiris; Kavetsos, Georgios

    2015-01-01

    Previous research shows that the announcement of austerity measures leads to an immediate and short-lived increase in behaviour that demonstrates anxiety, stress, frustration and other mental effects. This paper uses evidence from the same natural experiment to study whether, for a given decision to commit suicide (as documented by the overall increase over the study period), suicides follow immediately after the announcement of austerity measures in Greece; or whether this is an effect that matures in peoples' minds before being transformed into action. We use evidence from a natural experiment and follow an econometric approach. Our findings show that, despite an overall sharp increase in suicides over the study period, the increase does not follow immediately in the first few days after each such negative event. This suggests that suicides are not spontaneous. They are rather decisions that take time to mature. This time lag implies that suicides arguably attributed to recessions are, in principle, preventable and underlines the importance of mental health services. PMID:26844154

  14. Embodying an outgroup: the role of racial bias and the effect of multisensory processing in somatosensory remapping.

    PubMed

    Fini, Chiara; Cardini, Flavia; Tajadura-Jiménez, Ana; Serino, Andrea; Tsakiris, Manos

    2013-01-01

    We come to understand other people's physical and mental states by re-mapping their bodily states onto our sensorimotor system. This process, also called somatosensory resonance, is an essential ability for social cognition and is stronger when observing ingroup than outgroup members. Here we investigated, first, whether implicit racial bias constrains somatosensory resonance, and second, whether increasing the ingroup/outgroup perceived physical similarity results in an increase in the somatosensory resonance for outgroup members. We used the Visual Remapping of Touch effect as an index of individuals' ability in resonating with the others, and the Implicit Association Test to measure racial bias. In Experiment 1, participants were asked to detect near-threshold tactile stimuli delivered to their own face while viewing either an ingroup or an outgroup face receiving a similar stimulation. Our results showed that individuals' tactile accuracy when viewing an outgroup face being touched was negatively correlated to their implicit racial bias. In Experiment 2, participants received the interpersonal multisensory stimulation (IMS) while observing an outgroup member. IMS has been found to increase the perceived physical similarity between the observer's and the observed body. We tested whether such increase in ingroup/outgroup perceived physical similarity increased the remapping ability for outgroup members. We found that after sharing IMS experience with an outgroup member, tactile accuracy when viewing touch on outgroup faces increased. Interestingly, participants with stronger implicit bias against the outgroup showed larger positive change in the remapping. We conclude that shared multisensory experiences might represent one key way to improve our ability to resonate with others by overcoming the boundaries between ingroup and outgroup categories.

  15. Embodying an outgroup: the role of racial bias and the effect of multisensory processing in somatosensory remapping

    PubMed Central

    Fini, Chiara; Cardini, Flavia; Tajadura-Jiménez, Ana; Serino, Andrea; Tsakiris, Manos

    2013-01-01

    We come to understand other people's physical and mental states by re-mapping their bodily states onto our sensorimotor system. This process, also called somatosensory resonance, is an essential ability for social cognition and is stronger when observing ingroup than outgroup members. Here we investigated, first, whether implicit racial bias constrains somatosensory resonance, and second, whether increasing the ingroup/outgroup perceived physical similarity results in an increase in the somatosensory resonance for outgroup members. We used the Visual Remapping of Touch effect as an index of individuals' ability in resonating with the others, and the Implicit Association Test to measure racial bias. In Experiment 1, participants were asked to detect near-threshold tactile stimuli delivered to their own face while viewing either an ingroup or an outgroup face receiving a similar stimulation. Our results showed that individuals' tactile accuracy when viewing an outgroup face being touched was negatively correlated to their implicit racial bias. In Experiment 2, participants received the interpersonal multisensory stimulation (IMS) while observing an outgroup member. IMS has been found to increase the perceived physical similarity between the observer's and the observed body. We tested whether such increase in ingroup/outgroup perceived physical similarity increased the remapping ability for outgroup members. We found that after sharing IMS experience with an outgroup member, tactile accuracy when viewing touch on outgroup faces increased. Interestingly, participants with stronger implicit bias against the outgroup showed larger positive change in the remapping. We conclude that shared multisensory experiences might represent one key way to improve our ability to resonate with others by overcoming the boundaries between ingroup and outgroup categories. PMID:24302900

  16. The impact of instrumental feeding on children's responses to taste exposure.

    PubMed

    Añez, E; Remington, A; Wardle, J; Cooke, L

    2013-10-01

    In a recent study, we showed that nonfood incentives combined with taste exposure increase children's acceptance of vegetables. However, the impact of children's previous experience of receiving food rewards is unknown. The present study investigated whether the experience of food rewards affects responses to an exposure-plus-reward intervention. One hundred and thirty-seven parents of 4-6-year-old children taking part in an exposure-based intervention study completed an instrumental feeding (IF) questionnaire aiming to assess their use of food rewards. Based on these scores, children were categorised as frequently or rarely instrumentally-fed. Intervention groups were given 12 daily tastes of a target vegetable combined with no reward, a tangible reward, (sticker) or a verbal reward (praise). A no-treatment control group received no tastings. Liking and intake of a target vegetable were measured at baseline and post-intervention. Irrespective of experience of IF, children in all intervention groups increased liking compared to controls (all P < 0.001) and both reward groups increased intake compared to controls (both P < 0.05). However, in the nonrewarded exposure group, only children with a limited experience with food rewards increased consumption (P < 0.05). Experience of IF may limit the benefits of 'mere exposure'. However, exposure with nonfood rewards can increase the acceptance of vegetables, regardless of previous experience. © 2012 The Authors Journal of Human Nutrition and Dietetics © 2012 The British Dietetic Association Ltd.

  17. Learning to control an SSVEP-based BCI speller in naïve subjects.

    PubMed

    Zhihua Tang; Yijun Wang; Guoya Dong; Weihua Pei; Hongda Chen

    2017-07-01

    High-speed steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) has been demonstrated in several recent studies. This study aimed to investigate some issues regarding feasibility of learning to control an SSVEP-based BCI speller in naïve subjects. An experiment with new BCI users was designed to answer the following questions: (1) How many people can use the SSVEP-BCI speller? (2) How much time is required to train the user? (3) Does continuous system use lead to user fatigue and deteriorated BCI performance? The experiment consisted of three tasks including a 40-class BCI spelling task, a psychomotor vigilance test (PVT) task, and a test of sleepiness scale. Subjects' reaction time (RT) in the PVT task and the fatigue rank in the sleepiness scale test were used as objective and subjective parameters to evaluate subjects' alertness level. Among 11 naïve subjects, 10 of them fulfilled the 9-block experiment. Four of them showed clear learning effects (i.e., an increasing trend of classification accuracy and information transfer rate (ITR)) over time. The remaining subjects showed stable BCI performance during the whole experiment. The results of RT and fatigue rank showed a gradually increasing trend, which is not significant across blocks. In summary, the results of this study suggest that controlling an SSVEP-based BCI speller is in general feasible to learn by naïve subjects after a short training procedure, showing no clear performance deterioration related to fatigue.

  18. Stimulus-level interference disrupts repetition benefit during task switching in middle childhood

    PubMed Central

    Karayanidis, Frini; Jamadar, Sharna; Sanday, Dearne

    2013-01-01

    The task-switching paradigm provides a powerful tool to measure the development of core cognitive control processes. In this study, we use the alternating runs task-switching paradigm to assess preparatory control processes involved in flexibly preparing for a predictable change in task and stimulus-driven control processes involved in controlling stimulus-level interference. We present three experiments that examine behavioral and event-related potential (ERP) measures of task-switching performance in middle childhood and young adulthood under low and high stimulus interference conditions. Experiment 1 confirms that our new child-friendly tasks produce similar behavioral and electrophysiological findings in young adults as those previously reported. Experiment 2 examines task switching with univalent stimuli across a range of preparation intervals in middle childhood. Experiment 3 compares task switching with bivalent stimuli across the same preparation intervals in children and young adults. Children produced a larger RT switch cost than adults with univalent stimuli and a short preparation interval. Both children and adults showed significant reduction in switch cost with increasing preparation interval, but in children this was caused by greater increase in RT for repeat than switch trials. Response-locked ERPs showed intact preparation for univalent, but less efficient preparation for bivalent stimulus conditions. Stimulus-locked ERPs confirmed that children showed greater stimulus-level interference for repeat trials, especially with bivalent stimuli. We conclude that children show greater stimulus-level interference especially for repeat trials under high interference conditions, suggesting weaker mental representation of the current task set. PMID:24367317

  19. Isolation and Characterization of Chromosome-Gain and Increase-in-Ploidy Mutants in Yeast

    PubMed Central

    Chan, CSM.; Botstein, D.

    1993-01-01

    We have developed a colony papillation assay for monitoring the copy number of genetically marked chromosomes II and III in Saccharomyces cerevisiae. The unique feature of this assay is that it allows detection of a gain of the marked chromosomes even if there is a gain of the entire set of chromosomes (increase-in-ploidy). This assay was used to screen for chromosome-gain or increase-in-ploidy mutants. Five complementation groups have been defined for recessive mutations that confer an increase-in-ploidy (ipl) phenotype, which, in each case, cosegregates with a temperature-sensitive growth phenotype. Four new alleles of CDC31, which is required for spindle pole body duplication, were also recovered from this screen. Temperature-shift experiments with ipl1 cells show that they suffer severe nondisjunction at 37°. Similar experiments with ipl2 cells show that they gain entire sets of chromosomes and become arrested as unbudded cells at 37°. Molecular cloning and genetic mapping show that IPL1 is a newly identified gene, whereas IPL2 is allelic to BEM2, which is required for normal bud growth. PMID:8293973

  20. Reductive Dechlorination of Carbon Tetrachloride by Soil With Ferrous and Bisulfide

    NASA Astrophysics Data System (ADS)

    Choi, K.; Lee, W.

    2008-12-01

    Batch and column experiments were conducted to investigate the effect of concentration of reductants, contact time to activate reductive capacity, and pH on reductive dechlorination by soil with Fe(II) and HS- in this study. Carbon tetrachloride (CT) was used as a representative target organic compound. Sorption kinetic and isotherm tests were performed to investigate the influence of adsorption on the soil surface. Target compound in the soil suspension reached sorption equilibrium in 4 hours and the type of isotherm was well fitted by a linear type isotherm. In batch experiment, kinetic rate constants for the reductive dechlorination of CT increased with increasing the concentration of the reductants (Fe(II) and HS-). However, Fe(II) was a much more effective reductant, producing higher k values than those of HS-. The contact time of one day for the soil with HS- and that of four hours with Fe(II) showed the highest reaction rates. Additionally, the rate constants increased with the increase of pH in soil suspension with Fe(II) (5.2~8) and HS- (8.3~10.3), respectively. In column experiment, the soil column with Fe(II) showed larger bed volumes (13.76) to reach a column breakthrough than that with HS- indicating the treatment of Fe(II) is more effective for the reductive dechlorination of CT. To enhance reductive capacity of soil column under an acidic condition, CaO addition to the column treated with Fe(II) showed better results for the reductive dechlorination of CT than that of HS-. Fe(II) showed better CT dechlorination than HS- in batch and column reactors therefore, it can be used as an effective reducing agent for the treatment of soil contaminated with chlorinated organic compounds.

  1. The Microstructural Evolution of Quartzite During Gradually Increasing Stress.

    NASA Astrophysics Data System (ADS)

    Soleymani, Hamid; Kidder, Steven B.; Hirth, Greg

    2016-12-01

    In settings where rocks are exhumed along shear zones, mylonites are thought to experience a gradual increase in stress and localization as they approach the brittle-ductile transition (Figure 1. left panel). Our aim is to investigate the microstructural characteristics of experimental samples that have experienced such a stress path and make comparisons to natural samples. A common characteristic of recrystallized grains in shear zones is what appears, at least qualitatively, to be a bimodal distribution of grain size (Figure 1. right panel). We hypothesize that such distributions might form as a natural consequence of a gradual stress increase in rocks approaching the brittle-ductile transition. We carried out several general-shear, Griggs rig experiments on Arkansas novaculite ( 10 micron grain size) and Black Hills quartzite synthesized powder (10-20 micron) annealed at 915°C and confining pressure of 1.5 GPa. To simulate exhumation, stress was increased by gradually decreasing the temperature at various constant rates. Experimental design and mechanical data are presented along with a discussion on grain growth and evolution. Initial results show that the technique is able to successfully simulate the exhumation stre­­­­ss path. The experiments also show that novaculite is roughly twice as strong (at similar water concentrations) as Black Hills quartzite powder ( 10-20 microns). We anticipate that detailed, quantitative study of the microstructure and grain statistics of experiments of this type can lead to improved interpretation of the microstructural development of natural samples.

  2. Rainfall simulation experiments: Influence of water temperature, water quality and plot design on soil erosion and runoff

    NASA Astrophysics Data System (ADS)

    Iserloh, Thomas; Pegoraro, Dominique; Schlösser, Angelika; Thesing, Hannah; Seeger, Manuel; Ries, Johannes B.

    2015-04-01

    Field rainfall simulators are designed to study soil erosion processes and provide urgently needed data for various geomorphological, hydrological and pedological issues. Due to the different conditions and technologies applied, there are several methodological aspects under review of the scientific community, particularly concerning design, procedures and conditions of measurement for infiltration, runoff and soil erosion. This study aims at contributing fundamental data for understanding rainfall simulations in depth by studying the effect of the following parameters on the measurement results: 1. Plot design - round or rectangular plot: Can we identify differences in amount of runoff and erosion? 2. Water quality: What is the influence of the water's salt load on interrill erosion and infiltration as measured by rainfall experiments? 3. Water temperature: How much are the results conditioned by the temperature of water, which is subject to changes due to environmental conditions during the experiments? Preliminary results show a moderate increase of soil erosion with the water's salt load while runoff stays almost on the same level. With increasing water temperature, runoff increases continuously. At very high temperatures, soil erosion is clearly increased. A first comparison between round and rectangular plot indicates the rectangular plot to be the most suitable plot shape, but ambiguous results make further research necessary. The analysis of these three factors concerning their influence on runoff and erosion shows that clear methodological standards are necessary in order to make rainfall simulation experiments comparable.

  3. Influence of an Intermediate Option on the Description-Experience Gap and Information Search

    PubMed Central

    Sharma, Neha; Debnath, Shoubhik; Dutt, Varun

    2018-01-01

    Research shows that people tend to overweight small probabilities in description and underweight them in experience, thereby leading to a different pattern of choices between description and experience; a phenomenon known as the Description-Experience (DE) gap. However, little is known on how the addition of an intermediate option and contextual framing influences the DE gap and people’s search strategies. This paper tests the effects of an intermediate option and contextual framing on the DE gap and people’s search strategies, where problems require search for information before a consequential choice. In the first experiment, 120 participants made choice decisions across investment problems that differed in the absence or presence of an intermediate option. Results showed that adding an intermediate option did not reduce the DE gap on the maximizing option across a majority of problems. There were a large majority of choices for the intermediate option. Furthermore, there was an increase in switching between options due to the presence of the intermediate option. In the second experiment, 160 participants made choice decisions in problems like those presented in experiment 1; however, problems lacked the investment framing. Results replicated findings from the first experiment and showed a similar DE gap on the maximizing option in a majority of problems in both the absence and presence of the intermediate option. Again, there were a large majority of choices for the intermediate option. Also, there was an increase in switching between options due to the presence of the intermediate option. Meta-analyses revealed that the absence or presence of the intermediate option created certain differences in the strength of frequency and recency processes. Also, a single natural-mean heuristic model was able to account for the experimental results across both experiments. We discuss implications of our findings to consequential decisions made after information search. PMID:29643821

  4. Influence of an Intermediate Option on the Description-Experience Gap and Information Search.

    PubMed

    Sharma, Neha; Debnath, Shoubhik; Dutt, Varun

    2018-01-01

    Research shows that people tend to overweight small probabilities in description and underweight them in experience, thereby leading to a different pattern of choices between description and experience; a phenomenon known as the Description-Experience (DE) gap. However, little is known on how the addition of an intermediate option and contextual framing influences the DE gap and people's search strategies. This paper tests the effects of an intermediate option and contextual framing on the DE gap and people's search strategies, where problems require search for information before a consequential choice. In the first experiment, 120 participants made choice decisions across investment problems that differed in the absence or presence of an intermediate option. Results showed that adding an intermediate option did not reduce the DE gap on the maximizing option across a majority of problems. There were a large majority of choices for the intermediate option. Furthermore, there was an increase in switching between options due to the presence of the intermediate option. In the second experiment, 160 participants made choice decisions in problems like those presented in experiment 1; however, problems lacked the investment framing. Results replicated findings from the first experiment and showed a similar DE gap on the maximizing option in a majority of problems in both the absence and presence of the intermediate option. Again, there were a large majority of choices for the intermediate option. Also, there was an increase in switching between options due to the presence of the intermediate option. Meta-analyses revealed that the absence or presence of the intermediate option created certain differences in the strength of frequency and recency processes. Also, a single natural-mean heuristic model was able to account for the experimental results across both experiments. We discuss implications of our findings to consequential decisions made after information search.

  5. Zinc allocation and re-allocation in rice.

    PubMed

    Stomph, Tjeerd Jan; Jiang, Wen; Van Der Putten, Peter E L; Struik, Paul C

    2014-01-01

    Agronomy and breeding actively search for options to enhance cereal grain Zn density. Quantifying internal (re-)allocation of Zn as affected by soil and crop management or genotype is crucial. We present experiments supporting the development of a conceptual model of whole plant Zn allocation and re-allocation in rice. Two solution culture experiments using (70)Zn applications at different times during crop development and an experiment on within-grain distribution of Zn are reported. In addition, results from two earlier published experiments are re-analyzed and re-interpreted. A budget analysis showed that plant zinc accumulation during grain filling was larger than zinc allocation to the grains. Isotope data showed that zinc taken up during grain filling was only partly transported directly to the grains and partly allocated to the leaves. Zinc taken up during grain filling and allocated to the leaves replaced zinc re-allocated from leaves to grains. Within the grains, no major transport barrier was observed between vascular tissue and endosperm. At low tissue Zn concentrations, rice plants maintained concentrations of about 20 mg Zn kg(-1) dry matter in leaf blades and reproductive tissues, but let Zn concentrations in stems, sheath, and roots drop below this level. When plant zinc concentrations increased, Zn levels in leaf blades and reproductive tissues only showed a moderate increase while Zn levels in stems, roots, and sheaths increased much more and in that order. In rice, the major barrier to enhanced zinc allocation towards grains is between stem and reproductive tissues. Enhancing root to shoot transfer will not contribute proportionally to grain zinc enhancement.

  6. The Effects of Selected Hot and Cold Temperament Herbs Based on Iranian Traditional Medicine on Some Metabolic Parameters in Normal Rats

    PubMed Central

    Parvinroo, Shirin; Zahediasl, Saleh; Sabetkasaei, Masoumeh; Kamalinejad, Mohammad; Naghibi, Farzaneh

    2014-01-01

    This study was aimed to evaluate the effects of diets containing some hot and cold temperament herb seeds according to Iranian traditional medicine (ITM) on some metabolic parameters in acute (24 h) and sub-acute (7 day) experiments that were performed on rats. For each experiment, effects of diets containing 10% herb seeds in category of hot (anise, fennel, ajowan) and cold (cucumber, watermelon, pumpkin) temperaments were analyzed on body weight gain, food intake, water consumption, urine output, serum glucose (SG) and insulin levels of rats. In the acute experiment, anise or fennel fed groups showed a significant decrease in food intake and there were not any changes in other parameters. The hot temperament groups in comparison with the cold temperament ones showed a significant decrease in food intake and a significant increase in SG level. In the sub-acute experiment, anise and fennel fed groups had a significant decrease in body weight gain on the 4thday. On the 7th day, the anise fed group experienced a significant decrease in body weight gain and a significant increase in SG levels. The groups that were fed hot temperament diets compared to the ones that consumed cold temperament diets showed a significant decrease in body weight gain and food intake rates and a considerable increase in SG levels. Considering the findings of this study, one can conclude that it is possible that hot temperament herbs such as anise and fennel be useful for humans for certain conditions such as weight control. PMID:24711844

  7. Zinc allocation and re-allocation in rice

    PubMed Central

    Stomph, Tjeerd Jan; Jiang, Wen; Van Der Putten, Peter E. L.; Struik, Paul C.

    2014-01-01

    Aims: Agronomy and breeding actively search for options to enhance cereal grain Zn density. Quantifying internal (re-)allocation of Zn as affected by soil and crop management or genotype is crucial. We present experiments supporting the development of a conceptual model of whole plant Zn allocation and re-allocation in rice. Methods: Two solution culture experiments using 70Zn applications at different times during crop development and an experiment on within-grain distribution of Zn are reported. In addition, results from two earlier published experiments are re-analyzed and re-interpreted. Results: A budget analysis showed that plant zinc accumulation during grain filling was larger than zinc allocation to the grains. Isotope data showed that zinc taken up during grain filling was only partly transported directly to the grains and partly allocated to the leaves. Zinc taken up during grain filling and allocated to the leaves replaced zinc re-allocated from leaves to grains. Within the grains, no major transport barrier was observed between vascular tissue and endosperm. At low tissue Zn concentrations, rice plants maintained concentrations of about 20 mg Zn kg−1 dry matter in leaf blades and reproductive tissues, but let Zn concentrations in stems, sheath, and roots drop below this level. When plant zinc concentrations increased, Zn levels in leaf blades and reproductive tissues only showed a moderate increase while Zn levels in stems, roots, and sheaths increased much more and in that order. Conclusions: In rice, the major barrier to enhanced zinc allocation towards grains is between stem and reproductive tissues. Enhancing root to shoot transfer will not contribute proportionally to grain zinc enhancement. PMID:24478788

  8. Mecp2 Mediates Experience-Dependent Transcriptional Upregulation of Ryanodine Receptor Type-3.

    PubMed

    Torres, Rodrigo F; Hidalgo, Cecilia; Kerr, Bredford

    2017-01-01

    Mecp2 is a DNA methylation reader that plays a critical role in experience-dependent plasticity. Increasing evidence supports a role for epigenetic modifications in activity-induced gene expression. Hence, candidate genes related to such phenomena are of great interest. Ryanodine receptors are intracellular calcium channels that contribute to hippocampal synaptic plasticity, dendritic spine remodeling, and participate in learning and memory processes. Here we exposed mice to the enriched environment (EE) paradigm, which through increased stimulation induces experience dependent-plasticity, to explore a role for methyl-cytosines, and Mecp2 in directing Ryanodine receptor 3 ( Ryr3 ) transcriptional activity. EE induced a hippocampal-specific increase in the methylation of discrete cytosines located at a Ryr3 isoform promoter; chromatin immunoprecipitation experiments revealed that EE increased Mecp2 binding to this Ryr3 isoform promoter. Interestingly, the experimental paradigm induced robust Ryr3 upregulation, accompanied by miR132 -dependent suppression of p250GAP , a pathway driving synaptogenesis. In contrast to WT mice, Mecp2-null mice showed diminished levels of Ryr3 and displayed impaired EE-induced Ryr3 upregulation, compromising miR132 dependent suppression of p250GAP and experience-dependent structural plasticity. Based on these results, we propose that Mecp2 acts as a transcriptional activator of Ryr3 , contributing to experience-dependent plasticity.

  9. Mechanisms of impulsive choice: II. Time-based interventions to improve self-control

    PubMed Central

    Smith, Aaron P.; Marshall, Andrew T.; Kirkpatrick, Kimberly

    2014-01-01

    Impulsive choice behavior has been proposed as a primary risk factor for other maladaptive behaviors (e.g., gambling, substance abuse). Recent research has suggested that timing processes may play a key role in impulsive choice behavior, and could provide an avenue for altering impulsive choice. Accordingly, the current experiments assessed a set of time-based behavioral interventions to increase self-control while simultaneously assessing effects on timing processes within the impulsive choice task. Three experiments assessed temporal interventions using a differential reinforcement of low rates task (Experiment 1) and exposure to either a variable or fixed interval schedule (Experiments 2–3). The efficacy of the interventions was assessed in Sprague-Dawley (Experiments 1–2) and Lewis (Experiment 3) rat strains. Impulsive choice behavior was assessed by measuring preferences of a smaller-sooner (SS) versus a larger-later (LL) reward, while timing of the SS and LL durations was measured during peak trials within the impulsive choice procedure. The rats showed an increased preference for the LL following all three time-based interventions and also displayed increased temporal precision. These results add to the increasing evidence that supports a possible role for temporal processing in impulsive choice behavior and supply novel behavioral interventions to decrease impulsive behavior. PMID:25444771

  10. A three-dimensional finite element model of near-field scanning microwave microscopy

    NASA Astrophysics Data System (ADS)

    Balusek, Curtis; Friedman, Barry; Luna, Darwin; Oetiker, Brian; Babajanyan, Arsen; Lee, Kiejin

    2012-10-01

    A three-dimensional finite element model of an experimental near-field scanning microwave microscope (NSMM) has been developed and compared to experiment on non conducting samples. The microwave reflection coefficient S11 is calculated as a function of frequency with no adjustable parameters. There is qualitative agreement with experiment in that the resonant frequency can show a sizable increase with sample dielectric constant; a result that is not obtained with a two-dimensional model. The most realistic model shows a semi-quantitative agreement with experiment. The effect of different sample thicknesses and varying tip sample distances is investigated numerically and shown to effect NSMM performance in a way consistent with experiment. Visualization of the electric field indicates that the field is primarily determined by the shape of the coupling hooks.

  11. Simulation prediction and experiment setup of vacuum laser acceleration at Brookhaven National Lab-Accelerator Test Facility

    NASA Astrophysics Data System (ADS)

    Shao, L.; Cline, D.; Ding, X.; Ho, Y. K.; Kong, Q.; Xu, J. J.; Pogorelsky, I.; Yakimenko, V.; Kusche, K.

    2013-02-01

    This paper presents the pre-experiment plan and prediction of the first stage of vacuum laser acceleration (VLA) collaborating by UCLA, Fudan University and ATF-BNL. This first stage experiment is a proof-of-principle to support our previously posted novel VLA theory. Simulations show that based on ATF's current experimental conditions the electron beam with initial energy of 15 MeV can get net energy gain from an intense CO2 laser beam. The difference in electron beam energy spread is observable by the ATF beam line diagnostics system. Further, this energy spread expansion effect increases along with an increase in laser intensity. The proposal has been approved by the ATF committee and the experiment will be our next project.

  12. Can representational trajectory reveal the nature of an internal model of gravity?

    PubMed

    De Sá Teixeira, Nuno; Hecht, Heiko

    2014-05-01

    The memory for the vanishing location of a horizontally moving target is usually displaced forward in the direction of motion (representational momentum) and downward in the direction of gravity (representational gravity). Moreover, this downward displacement has been shown to increase with time (representational trajectory). However, the degree to which different kinematic events change the temporal profile of these displacements remains to be determined. The present article attempts to fill this gap. In the first experiment, we replicate the finding that representational momentum for downward-moving targets is bigger than for upward motions, showing, moreover, that it increases rapidly during the first 300 ms, stabilizing afterward. This temporal profile, but not the increased error for descending targets, is shown to be disrupted when eye movements are not allowed. In the second experiment, we show that the downward drift with time emerges even for static targets. Finally, in the third experiment, we report an increased error for upward-moving targets, as compared with downward movements, when the display is compatible with a downward ego-motion by including vection cues. Thus, the errors in the direction of gravity are compatible with the perceived event and do not merely reflect a retinotopic bias. Overall, these results provide further evidence for an internal model of gravity in the visual representational system.

  13. 16 CFR 1205.8 - Findings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... and nature of the risk of injury part 1205 is designed to eliminate or reduce. (1) The Commission... increase their utility. In the first place, consumers are likely to experience an increased sense of... (GSA) shows that almost all users appreciated the safety features on brake-clutch mowers. In addition...

  14. An evaluation of the Exer-Genie exerciser and the Collins pedal mode ergometer for developing physical fitness

    NASA Technical Reports Server (NTRS)

    Olree, H. D.

    1973-01-01

    Experiments that were conducted over a 52-month period showed that isometric and isotonic training on the Exer-Genie gave negligible increases in cardiorespiratory fitness whereas training on the ergometer at a programmed pulse rate increased fitness moderately.

  15. The Effects of the Compressed Workweek: A Review of the Evidence.

    ERIC Educational Resources Information Center

    Dawkins, Peter; Tulsi, Narmon

    1990-01-01

    A literature review showed substantial growth in the use of compressed work weeks. Employees benefited from increased leisure but suffered from increased fatigue and work disruption. Organizations might experience enhanced morale and less absenteeism as well as work coordination and communication problems. (SK)

  16. Understanding the Role of Openness to Experience in Study Abroad Students

    ERIC Educational Resources Information Center

    Martin, Daniela; Katz-Buonincontro, Jennifer; Livert, David

    2015-01-01

    In this article, the authors report on a study of 59 undergraduate students who completed a survey assessing aspects of openness to experience, race and cultural understanding, and critical thinking before and after they studied abroad for 3 months. Results showed an increase in students' knowledge of and ability to comprehend new cultures,…

  17. Increasing Performance by Differentiated Teaching? Experimental Evidence of the Student Benefits of Digital Differentiation

    ERIC Educational Resources Information Center

    Haelermans, Carla; Ghysels, Joris; Prince, Fernao

    2015-01-01

    This paper explores the effect of digital differentiation on student performance using a randomized experiment. The experiment is conducted in a second year biology class among 115 prevocational students in the Netherlands. Differentiation allowed students in the treatment group to work at three different levels. The results show that there is a…

  18. Surface tension measurements with a smartphone

    NASA Astrophysics Data System (ADS)

    Goy, Nicolas-Alexandre; Denis, Zakari; Lavaud, Maxime; Grolleau, Adrian; Dufour, Nicolas; Deblais, Antoine; Delabre, Ulysse

    2017-11-01

    Smartphones are increasingly used in higher education and at university in mechanics, acoustics, and even thermodynamics as they offer a unique way to do simple science experiments. In this article, we show how smartphones can be used in fluid mechanics to measure surface tension of various liquids, which could help students understand the concept of surface tension through simple experiments.

  19. Statistical modeling of isoform splicing dynamics from RNA-seq time series data.

    PubMed

    Huang, Yuanhua; Sanguinetti, Guido

    2016-10-01

    Isoform quantification is an important goal of RNA-seq experiments, yet it remains problematic for genes with low expression or several isoforms. These difficulties may in principle be ameliorated by exploiting correlated experimental designs, such as time series or dosage response experiments. Time series RNA-seq experiments, in particular, are becoming increasingly popular, yet there are no methods that explicitly leverage the experimental design to improve isoform quantification. Here, we present DICEseq, the first isoform quantification method tailored to correlated RNA-seq experiments. DICEseq explicitly models the correlations between different RNA-seq experiments to aid the quantification of isoforms across experiments. Numerical experiments on simulated datasets show that DICEseq yields more accurate results than state-of-the-art methods, an advantage that can become considerable at low coverage levels. On real datasets, our results show that DICEseq provides substantially more reproducible and robust quantifications, increasing the correlation of estimates from replicate datasets by up to 10% on genes with low or moderate expression levels (bottom third of all genes). Furthermore, DICEseq permits to quantify the trade-off between temporal sampling of RNA and depth of sequencing, frequently an important choice when planning experiments. Our results have strong implications for the design of RNA-seq experiments, and offer a novel tool for improved analysis of such datasets. Python code is freely available at http://diceseq.sf.net G.Sanguinetti@ed.ac.uk Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Research of energy characteristics of power amplifier containing KNFS Nd:phosphate glass slabs and MIRO Silver foil reflectors at the “Luch” facility

    NASA Astrophysics Data System (ADS)

    Belov, I. A.; Bel'kov, S. A.; Voronich, I. N.; Garanin, S. G.; Derkach, V. N.; Koshechkin, S. V.; Lysov, M. I.; Markov, S. S.; Savkin, S. V.

    2016-09-01

    The amplifier elements upgrade at the “Luch” laser facility was carried out. Measurements showed that the upgrade of the amplifier elements resulted in the amplifier's small signal gain coefficient K0 increase from 12.9% to 14.3% depending on the capacitor charging voltage; the linear gain coefficient increase was about g0 ≈ (6-8)%. Full-scale laser experiments at the facility showed the power amplifier gain coefficient increase consistent with active medium gain coefficient measurement results.

  1. The Role of Simple Semantics in the Process of Artificial Grammar Learning.

    PubMed

    Öttl, Birgit; Jäger, Gerhard; Kaup, Barbara

    2017-10-01

    This study investigated the effect of semantic information on artificial grammar learning (AGL). Recursive grammars of different complexity levels (regular language, mirror language, copy language) were investigated in a series of AGL experiments. In the with-semantics condition, participants acquired semantic information prior to the AGL experiment; in the without-semantics control condition, participants did not receive semantic information. It was hypothesized that semantics would generally facilitate grammar acquisition and that the learning benefit in the with-semantics conditions would increase with increasing grammar complexity. Experiment 1 showed learning effects for all grammars but no performance difference between conditions. Experiment 2 replicated the absence of a semantic benefit for all grammars even though semantic information was more prominent during grammar acquisition as compared to Experiment 1. Thus, we did not find evidence for the idea that semantics facilitates grammar acquisition, which seems to support the view of an independent syntactic processing component.

  2. Non-monotonic relationships between emotional arousal and memory for color and location.

    PubMed

    Boywitt, C Dennis

    2015-01-01

    Recent research points to the decreased diagnostic value of subjective retrieval experience for memory accuracy for emotional stimuli. While for neutral stimuli rich recollective experiences are associated with better context memory than merely familiar memories this association appears questionable for emotional stimuli. The present research tested the implicit assumption that the effect of emotional arousal on memory is monotonic, that is, steadily increasing (or decreasing) with increasing arousal. In two experiments emotional arousal was manipulated in three steps using emotional pictures and subjective retrieval experience as well as context memory were assessed. The results show an inverted U-shape relationship between arousal and recognition memory but for context memory and retrieval experience the relationship was more complex. For frame colour, context memory decreased linearly while for spatial location it followed the inverted U-shape function. The complex, non-monotonic relationships between arousal and memory are discussed as possible explanations for earlier divergent findings.

  3. Investigating three types of continuous auditory feedback in visuo-manual tracking.

    PubMed

    Boyer, Éric O; Bevilacqua, Frédéric; Susini, Patrick; Hanneton, Sylvain

    2017-03-01

    The use of continuous auditory feedback for motor control and learning is still understudied and deserves more attention regarding fundamental mechanisms and applications. This paper presents the results of three experiments studying the contribution of task-, error-, and user-related sonification to visuo-manual tracking and assessing its benefits on sensorimotor learning. First results show that sonification can help decreasing the tracking error, as well as increasing the energy in participant's movement. In the second experiment, when alternating feedback presence, the user-related sonification did not show feedback dependency effects, contrary to the error and task-related feedback. In the third experiment, a reduced exposure of 50% diminished the positive effect of sonification on performance, whereas the increase of the average energy with sound was still significant. In a retention test performed on the next day without auditory feedback, movement energy was still superior for the groups previously trained with the feedback. Although performance was not affected by sound, a learning effect was measurable in both sessions and the user-related group improved its performance also in the retention test. These results confirm that a continuous auditory feedback can be beneficial for movement training and also show an interesting effect of sonification on movement energy. User-related sonification can prevent feedback dependency and increase retention. Consequently, sonification of the user's own motion appears as a promising solution to support movement learning with interactive feedback.

  4. Extreme ultraviolet patterning of tin-oxo cages

    NASA Astrophysics Data System (ADS)

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

    2017-07-01

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

  5. Designing Effective Persuasive Systems Utilizing the Power of Entanglement: Communication Channel, Strategy and Affect

    NASA Astrophysics Data System (ADS)

    Li, Haiqing; Chatterjee, Samir

    With rapid advances in information and communication technology, computer-mediated communication (CMC) technologies are utilizing multiple IT platforms such as email, websites, cell-phones/PDAs, social networking sites, and gaming environments. However, no studies have compared the effectiveness of a persuasive system using such alternative channels and various persuasive techniques. Moreover, how affective computing impacts the effectiveness of persuasive systems is not clear. This study proposes (1) persuasive technology channels in combination with persuasive strategies will have different persuasive effectiveness; (2) Adding positive emotion to a message that leads to a better overall user experience could increase persuasive effectiveness. The affective computing or emotion information was added to the experiment using emoticons. The initial results of a pilot study show that computer-mediated communication channels along with various persuasive strategies can affect the persuasive effectiveness to varying degrees. These results also shows that adding a positive emoticon to a message leads to a better user experience which increases the overall persuasive effectiveness of a system.

  6. Effect of hydrothermal liquefaction aqueous phase recycling on bio-crude yields and composition.

    PubMed

    Biller, Patrick; Madsen, René B; Klemmer, Maika; Becker, Jacob; Iversen, Bo B; Glasius, Marianne

    2016-11-01

    Hydrothermal liquefaction (HTL) is a promising thermo-chemical processing technology for the production of biofuels but produces large amounts of process water. Therefore recirculation of process water from HTL of dried distillers grains with solubles (DDGS) is investigated. Two sets of recirculation on a continuous reactor system using K2CO3 as catalyst were carried out. Following this, the process water was recirculated in batch experiments for a total of 10 rounds. To assess the effect of alkali catalyst, non-catalytic HTL process water recycling was performed with 9 recycle rounds. Both sets of experiments showed a large increase in bio-crude yields from approximately 35 to 55wt%. The water phase and bio-crude samples from all experiments were analysed via quantitative gas chromatography-mass spectrometry (GC-MS) to investigate their composition and build-up of organic compounds. Overall the results show an increase in HTL conversion efficiency and a lower volume, more concentrated aqueous by-product following recycling. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Effects of polluting soil with cassava mill effluent on the bacteria and fungi populations of a soil cultivated with maize.

    PubMed

    Ogboghodo, I A; Oluwafemi, A P; Ekeh, S M

    2006-05-01

    The study was carried out to investigate the effects of application of cassava mill effluent on bacteria and fungi types and population in a soil grown to maize (Zea Mays L.) Microbial populations were determined before pollution of soil with cassava mill effluent, six weeks after pollution with effluent and at the end of the experiment. Results obtained showed that bacteria and fungi populations increased with time as rates of pollution increased. It was also observed that some bacteria present in the soil at the beginning of the experiment and up to the sixth week after pollution with effluent became extinct at the end of the experiment.

  8. Biofilm resilience to desiccation in groundwater aquifers: a laboratory and field study.

    PubMed

    Weaver, L; Webber, J B; Hickson, A C; Abraham, P M; Close, M E

    2015-05-01

    Groundwater is used as a precious resource for drinking water worldwide. Increasing anthropogenic activity is putting increasing pressure on groundwater resources. One impact of increased groundwater abstraction coupled with increasing dry weather events is the lowering of groundwater levels within aquifers. Biofilms within groundwater aquifers offer protection to the groundwater by removing contaminants entering the aquifer systems from land use activities. The study presented investigated the impact of desiccation events on the biofilms present in groundwater aquifers using field and laboratory experiments. In both field and laboratory experiments a reduction in enzyme activity (glucosidase, esterase and phosphatase) was seen during desiccation compared to wet controls. However, comparing all the data together no significant differences were seen between either wet or desiccated samples or between the start and end of the experiments. In both field and laboratory experiments enzyme activity recovered to start levels after return to wet conditions. The study shows that biofilms within groundwater systems are resilient and can withstand periods of desiccation (4 months). Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Origin of temperature plateaus in laser-heated diamond anvil cell experiments

    NASA Astrophysics Data System (ADS)

    Geballe, Zachary M.; Jeanloz, Raymond

    2012-06-01

    Many high-pressure high-temperature studies using laser-heated diamond cells have documented plateaus in the increase of temperature with increasing laser power or with time. By modeling heat transfer in typical laser-heated diamond anvil cell experiments, we demonstrate that latent heat due to melting or other phase transformation is unlikely to be the source of observed plateaus in any previously published studies, regardless of whether pulsed or continuous lasers were used. Rather, large increases (˜10-fold) in thermal conductivity can explain some of the plateaus, and modest increases in reflectivity (tens of percent) can explain any or all of them. Modeling also shows that the sub-microsecond timescale of heating employed in recent pulsed heating experiments is fast enough compared to heat transport into and through typical insulations, but too slow compared to heat transport into metallic laser absorbers themselves to allow the detection of a large plateau due to latent heat of fusion. Four new designs are suggested for future experiments that could use the simple observation of a latent heat-induced plateau to provide reliable high-pressure melting data.

  10. Accelerated dissolution testing for controlled release microspheres using the flow-through dissolution apparatus.

    PubMed

    Collier, Jarrod W; Thakare, Mohan; Garner, Solomon T; Israel, Bridg'ette; Ahmed, Hisham; Granade, Saundra; Strong, Deborah L; Price, James C; Capomacchia, A C

    2009-01-01

    Theophylline controlled release capsules (THEO-24 CR) were used as a model system to evaluate accelerated dissolution tests for process and quality control and formulation development of controlled release formulations. Dissolution test acceleration was provided by increasing temperature, pH, flow rate, or adding surfactant. Electron microscope studies on the theophylline microspheres subsequent to each experiment showed that at pH values of 6.6 and 7.6 the microspheres remained intact, but at pH 8.6 they showed deterioration. As temperature was increased from 37-57 degrees C, no change in microsphere integrity was noted. Increased flow rate also showed no detrimental effect on integrity. The effect of increased temperature was determined to be the statistically significant variable.

  11. Treatment of high salinity organic wastewater by membrane electrolysis

    NASA Astrophysics Data System (ADS)

    Dongfang, Shen; Jinghuan, Ma; Ying, Liu; Chenguang, Zhao

    2018-03-01

    The effects of different operating conditions on the treatment of electrolytic wastewater were investigated by analyzing the removal rate of ammonia and COD before and after wastewater treatment by cation exchange membrane. Experiment shows that as the running time increases the electrolysis effect first increases after the smooth. The removal rate of ammonia will increase with the increase of current density, and the removal rate of COD will increase first and then decrease with the increase of current density. The increase of the temperature of the electrolytic solution will slowly increase the COD removal rate to saturation, but does not affect the removal of ammonia nitrogen. When the flow rate is less than 60L / h, the change of influent flow rate will not affect the removal of ammonia nitrogen, but the effect on COD is small, which will increase and decrease slightly. After the experiment, the surface of the cation exchange membrane was analyzed by cold field scanning electron microscopy and X-ray energy dispersive spectrometer. The surface contamination and the pollutant were determined. The experimental results showed that the aggregates were mainly chlorinated Sodium, calcium and magnesium inorganic salts, which will change the morphology of the film to reduce porosity, reduce the mass transfer efficiency, affecting the electrolysis effect.

  12. The attitudinal consequences of thought suppression: a focus on thinness thoughts.

    PubMed

    Tong, Eddie M W; Ang, Mei-San; Chua, Alvin S Y

    2013-03-01

    Four studies examined whether thought suppression could enhance attitude accessibility and whether behaviours that are consistent with the more accessible attitudes would follow. Thinness was examined as the attitude object. Experiments 1 and 2 showed that suppression of positive thoughts about thinness increased the accessibility of the positive attitudes associated with thinness. Experiments 3 and 4 showed that suppression of positive thinness thoughts also elicited more health-promoting behaviours. The implications of the findings for attitude accessibility and the practical consequences of thought suppression are discussed. © 2011 The British Psychological Society.

  13. Impact of Propene on Secondary Organic Aerosol Formation from m-Xylene

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

    Song, Chen; Na, Kwangsam; Warren, Bethany

    2007-10-15

    Propene is widely used in smog chamber experiments to increase the hydroxyl radical (OH) level based on the assumption that the formation of secondary organic aerosol (SOA) from parent hydrocarbon is unaffected. A series ofm-xylene/NOx photooxidation experiments were conducted in the presence of propene in the University of California CECERT atmospheric chamber facility. The experimental data are compared with previousm-xylene/NOx photooxidation work performed in the same chamber facility in the absence of propene (Song et al. Environ. Sci. Technol. 2005, 39, 3143-3149). The result shows that, for similar initial conditions, experiments with propene have lower reaction rates of m-xylene thanmore » those without propene, which indicates that propene reduces OH in the system. Furthermore, experiments with propene showed more than 15% reduction in SOA yield compared to experiments in the absence of propene. Additional experiments ofm-xylene/NOx with CO showed similar trends of suppressing OH and SOA formation. These results indicate that SOA from m-xylene/NOx photooxidation is strongly dependent on the OH level present, which provides evidence for the critical role of OH in SOA formation from aromatic hydrocarbons.« less

  14. Ants learn to rely on more informative attributes during decision-making.

    PubMed

    Sasaki, Takao; Pratt, Stephen C

    2013-01-01

    Evolutionary theory predicts that animals act to maximize their fitness when choosing among a set of options, such as what to eat or where to live. Making the best choice is challenging when options vary in multiple attributes, and animals have evolved a variety of heuristics to simplify the task. Many of these involve ranking or weighting attributes according to their importance. Because the importance of attributes can vary across time and place, animals might benefit by adjusting weights accordingly. Here, we show that colonies of the ant Temnothorax rugatulus use their experience during nest site selection to increase weights on more informative nest attributes. These ants choose their rock crevice nests on the basis of multiple features. After exposure to an environment where only one attribute differentiated options, colonies increased their reliance on this attribute relative to a second attribute. Although many species show experience-based changes in selectivity based on a single feature, this is the first evidence in animals for adaptive changes in the weighting of multiple attributes. These results show that animal collectives, like individuals, change decision-making strategies according to experience. We discuss how these colony-level changes might emerge from individual behaviour.

  15. Effects of rapeseed oil on the rhizodegradation of polyaromatic hydrocarbons in contaminated soil.

    PubMed

    Gartler, Jorg; Wimmer, Bernhard; Soja, Gerhard; Reichenauer, Thomas G

    2014-01-01

    Plants have the ability to promote degradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil by supporting PAH degrading microorganisms in the rhizosphere (rhizodegradation). The aim of this study was to evaluate if rapeseed oil increases rhizodegradation because various studies have shown that vegetable oils are able to act as extractants for PAHs in contaminated soils and therefore might increase bioavailability of PAHs for microbial degradation. In this study different leguminous and grass species were tested. The results suggested a significant impact of vegetable oil (1 and 3% w/w) on plant growth (decrease of plant height and biomass). The results of the pot experiment showed a decrease in the PAH content of the soil without amendment of rapeseed oil after six months. In soil amended with 1% and 3% of oil, there was no decrease in PAH content within this period. Although no enhancement of PAH degradation by plants could be measured in the bulk soil of the pot experiments, a rhizobox experiment showed a significant reduction of PAH content in the rhizosphere of alfalfa (Medicago sativa cv. Europe). Our investigations also showed significant differences in the degradation behaviour of the 16 individually analysed PAHs.

  16. Cadmium Phytoremediation by Arundo donax L. from Contaminated Soil and Water

    PubMed Central

    Sabeen, Maria; Mahmood, Qaisar; Irshad, Muhammad; Fareed, Iftikhar; Ullah, Farid; Hussain, Jamshaid; Hayat, Yousaf; Tabassum, Sobia

    2013-01-01

    The potential of Arundo donax L. for phytoextraction of cadmium (Cd) from contaminated soil and water was probed. The plants were grown under greenhouse conditions in pots containing a nutrient solution or soil with increasing doses of Cd (0, 50, 100, 250, 500, 750, and 1000 μg L−1) for 21 days. The growth and physiology of plants were evaluated at the end of the experiment. The maximum Cd content in root was 300 μg g−1 during hydroponics experiments over 230 μg g−1 in soil experiment. Cd concentration in stem was 262 μg g−1 at 750 μg L−1 supplied Cd in hydroponics over 191.2 μg g−1 at 1000 in soil experiment. The maximum Cd concentration in leaves from hydroponics was 187 μg g−1. Relatively low Cd uptake occurred during soil experiment with low translocation factor (TF) values. Both Bioaccumulation Factor (BF) and TF values for hydroponics were greater than 1. The IC50 values of ABTS and DPPH showed that both time and increasing Cd concentrations affected the production of antioxidants with lower half maximal inhibitory concentration (IC50) value on the 21st days. A. donax showed better potential for Cd remediation of aquatic environments. PMID:24459667

  17. Raising a School-Ready Child: A Family Guide

    ERIC Educational Resources Information Center

    Fong, G.; Hisatake,T.; Chang, W.; Choy, A.; Nemoto, M.; Yuen, S.

    2010-01-01

    School-ready children are children who are prepared to learn successfully in school. These children show growth over time in their physical, social and emotional, language, and cognitive development. They also show increasing interests in new experiences and in mastering new skills. Getting "school-ready" starts long before the weeks or…

  18. Categorizing document by fuzzy C-Means and K-nearest neighbors approach

    NASA Astrophysics Data System (ADS)

    Priandini, Novita; Zaman, Badrus; Purwanti, Endah

    2017-08-01

    Increasing of technology had made categorizing documents become important. It caused by increasing of number of documents itself. Managing some documents by categorizing is one of Information Retrieval application, because it involve text mining on its process. Whereas, categorization technique could be done both Fuzzy C-Means (FCM) and K-Nearest Neighbors (KNN) method. This experiment would consolidate both methods. The aim of the experiment is increasing performance of document categorize. First, FCM is in order to clustering training documents. Second, KNN is in order to categorize testing document until the output of categorization is shown. Result of the experiment is 14 testing documents retrieve relevantly to its category. Meanwhile 6 of 20 testing documents retrieve irrelevant to its category. Result of system evaluation shows that both precision and recall are 0,7.

  19. Enhanced phytoremediation of arsenic contaminated land.

    PubMed

    Jankong, P; Visoottiviseth, P; Khokiattiwong, S

    2007-08-01

    In an attempt to clean up arsenic (As) contaminated soil, the effects of phosphorus (P) fertilizer and rhizosphere microbes on arsenic accumulation by the silverback fern, Pityrogramma calomelanos, were investigated in both greenhouse and field experiments. Field experiments were conducted in Ron Phibun District, an As-contaminated area in Thailand. Soil (136-269 microg As g(-1)) was collected there and used in the greenhouse experiment. Rhizosphere microbes (bacteria and fungi) were isolated from roots of P. calomelanos growing in Ron Phibun District. The results showed that P-fertilizer significantly increased plant biomass and As accumulation of the experimental P. calomelanos. Rhizobacteria increased significantly the biomass and As content of the test plants. Thus, P-fertilizer and rhizosphere bacteria enhanced As-phytoextraction. In contrast, rhizofungi reduced significantly As concentration in plants but increased plant biomass. Therefore, rhizosphere fungi exerted their effects on phytostabilization.

  20. Prosocial benefits of feeling free: disbelief in free will increases aggression and reduces helpfulness.

    PubMed

    Baumeister, Roy F; Masicampo, E J; Dewall, C Nathan

    2009-02-01

    Laypersons' belief in free will may foster a sense of thoughtful reflection and willingness to exert energy, thereby promoting helpfulness and reducing aggression, and so disbelief in free will may make behavior more reliant on selfish, automatic impulses and therefore less socially desirable. Three studies tested the hypothesis that disbelief in free will would be linked with decreased helping and increased aggression. In Experiment 1, induced disbelief in free will reduced willingness to help others. Experiment 2 showed that chronic disbelief in free will was associated with reduced helping behavior. In Experiment 3, participants induced disbelief in free will caused participants to act more aggressively than others. Although the findings do not speak to the existence of free will, the current results suggest that disbelief in free will reduces helping and increases aggression.

  1. Removal of arsenic from aqueous solutions using waste iron columns inoculated with iron bacteria.

    PubMed

    Azhdarpoor, Abooalfazl; Nikmanesh, Roya; Samaei, Mohammad Reza

    2015-01-01

    Arsenic contamination of water resources is one of the serious risks threatening natural ecosystems and human health. This study investigates arsenic removal using a waste iron column with and without iron bacteria in continuous and batch phases. In batch experiments, the effects of pH, contact time, initial concentration of arsenic and adsorbent dose were investigated. Results indicated that the highest arsenate removal efficiency occurred at pH 7 (96.76%). On increasing the amount of waste iron from 0.25 to 1 g, the removal rate changed from about 42.37%-96.70%. The results of continuous experiments on the column containing waste iron showed that as the empty bed contact time increased from 5 to 60 min, the secondary arsenate concentration changed from 23 to 6 µg/l. In experiments involving a waste iron column with iron bacteria, an increase in residence time from 5 to 60 min decreased the secondary arsenate concentration from 14.97 to 4.86 µg/l. The results of this study showed that waste iron containing iron bacteria is a good adsorbent for removal of arsenic from contaminated water.

  2. Settling velocity and preferential concentration of heavy particles under two-way coupling effects in homogeneous turbulence

    NASA Astrophysics Data System (ADS)

    Monchaux, R.; Dejoan, A.

    2017-10-01

    The settling velocity of inertial particles falling in homogeneous turbulence is investigated by making use of direct numerical simulation (DNS) at moderate Reynolds number that include momentum exchange between both phases (two-way coupling approach). Effects of particle volume fraction, particle inertia, and gravity are presented for flow and particle parameters similar to the experiments of Aliseda et al. [J. Fluid Mech. 468, 77 (2002), 10.1017/S0022112002001593]. A good agreement is obtained between the DNS and the experiments for the settling velocity statistics, when overall averaged, but as well when conditioned on the local particle concentration. Both DNS and experiments show that the settling velocity further increases with increasing volume fraction and local concentration. At the considered particle loading the effects of two-way coupling is negligible on the mean statistics of turbulence. Nevertheless, the DNS results show that fluid quantities are locally altered by the particles. In particular, the conditional average on the local particle concentration of the slip velocity shows that the main contribution to the settling enhancement results from the increase of the fluid velocity surrounding the particles along the gravitational direction induced by the collective particle back-reaction force. Particles and the surrounding fluid are observed to fall together, which in turn results in an amplification of the sampling of particles in the downward fluid motion. Effects of two-way coupling on preferential concentration are also reported. Increase of both volume fraction and gravity is shown to lower preferential concentration of small inertia particles while a reverse tendency is observed for large inertia particles. This behavior is found to be related to an attenuation of the centrifuge effects and to an increase of particle accumulation along gravity direction, as particle loading and gravity become large.

  3. 16 CFR § 1205.8 - Findings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... and nature of the risk of injury part 1205 is designed to eliminate or reduce. (1) The Commission... increase their utility. In the first place, consumers are likely to experience an increased sense of... (GSA) shows that almost all users appreciated the safety features on brake-clutch mowers. In addition...

  4. Is induction produced by upcoming food-pellet reinforcement the outcome of an increase in overall activity or in operant responding?

    PubMed

    Weatherly, Jeffrey N; Arthur, Emily I L; Nurnberger, Jeri T

    2006-01-01

    Researchers have demonstrated that rats reliably increase their rates of pressing a lever for 1% liquid-sucrose reinforcement if they will soon have the opportunity to press a lever for food-pellet reinforcement. In the present experiments, the authors investigated if this increase in response rates occurred because the upcoming food pellets produced an increase in all behaviors (i.e., general arousal) or an increase in only the specific operant response (i.e., lever pressing). The results of Experiments 1 and 2 showed that the appearance of induction in rats' lever pressing for 1% sucrose reinforcement when food-pellet reinforcement was upcoming did not coincide with increases in the frequency of running in a wheel or making a nonreinforced nose-poke response. On the other hand, in Experiment 3, the authors found the appearance of induction coincided with increase nonreinforced lever presses on an adjacent lever. These results shed doubt on the idea that induction is a result of a general increase in all activity, and suggest instead that the increase in responding that occurs during induction is limited to the operant response.

  5. Experience-Dependent Plasticity in Accessory Olfactory Bulb Interneurons following Male-Male Social Interaction.

    PubMed

    Cansler, Hillary L; Maksimova, Marina A; Meeks, Julian P

    2017-07-26

    Chemosensory information processing in the mouse accessory olfactory system guides the expression of social behavior. After salient chemosensory encounters, the accessory olfactory bulb (AOB) experiences changes in the balance of excitation and inhibition at reciprocal synapses between mitral cells (MCs) and local interneurons. The mechanisms underlying these changes remain controversial. Moreover, it remains unclear whether MC-interneuron plasticity is unique to specific behaviors, such as mating, or whether it is a more general feature of the AOB circuit. Here, we describe targeted electrophysiological studies of AOB inhibitory internal granule cells (IGCs), many of which upregulate the immediate-early gene Arc after male-male social experience. Following the resident-intruder paradigm, Arc -expressing IGCs in acute AOB slices from resident males displayed stronger excitation than nonexpressing neighbors when sensory inputs were stimulated. The increased excitability of Arc -expressing IGCs was not correlated with changes in the strength or number of excitatory synapses with MCs but was instead associated with increased intrinsic excitability and decreased HCN channel-mediated I H currents. Consistent with increased inhibition by IGCs, MCs responded to sensory input stimulation with decreased depolarization and spiking following resident-intruder encounters. These results reveal that nonmating behaviors drive AOB inhibitory plasticity and indicate that increased MC inhibition involves intrinsic excitability changes in Arc -expressing interneurons. SIGNIFICANCE STATEMENT The accessory olfactory bulb (AOB) is a site of experience-dependent plasticity between excitatory mitral cells (MCs) and inhibitory internal granule cells (IGCs), but the physiological mechanisms and behavioral conditions driving this plasticity remain unclear. Here, we report studies of AOB neuronal plasticity following male-male social chemosensory encounters. We show that the plasticity-associated immediate-early gene Arc is selectively expressed in IGCs from resident males following the resident-intruder assay. After behavior, Arc -expressing IGCs are more strongly excited by sensory input stimulation and MC activation is suppressed. Arc -expressing IGCs do not show increased excitatory synaptic drive but instead show increased intrinsic excitability. These data indicate that MC-IGC plasticity is induced after male-male social chemosensory encounters, resulting in enhanced MC suppression by Arc -expressing IGCs. Copyright © 2017 the authors 0270-6474/17/377240-13$15.00/0.

  6. Experience-Dependent Plasticity in Accessory Olfactory Bulb Interneurons following Male–Male Social Interaction

    PubMed Central

    Maksimova, Marina A.

    2017-01-01

    Chemosensory information processing in the mouse accessory olfactory system guides the expression of social behavior. After salient chemosensory encounters, the accessory olfactory bulb (AOB) experiences changes in the balance of excitation and inhibition at reciprocal synapses between mitral cells (MCs) and local interneurons. The mechanisms underlying these changes remain controversial. Moreover, it remains unclear whether MC–interneuron plasticity is unique to specific behaviors, such as mating, or whether it is a more general feature of the AOB circuit. Here, we describe targeted electrophysiological studies of AOB inhibitory internal granule cells (IGCs), many of which upregulate the immediate-early gene Arc after male–male social experience. Following the resident–intruder paradigm, Arc-expressing IGCs in acute AOB slices from resident males displayed stronger excitation than nonexpressing neighbors when sensory inputs were stimulated. The increased excitability of Arc-expressing IGCs was not correlated with changes in the strength or number of excitatory synapses with MCs but was instead associated with increased intrinsic excitability and decreased HCN channel-mediated IH currents. Consistent with increased inhibition by IGCs, MCs responded to sensory input stimulation with decreased depolarization and spiking following resident–intruder encounters. These results reveal that nonmating behaviors drive AOB inhibitory plasticity and indicate that increased MC inhibition involves intrinsic excitability changes in Arc-expressing interneurons. SIGNIFICANCE STATEMENT The accessory olfactory bulb (AOB) is a site of experience-dependent plasticity between excitatory mitral cells (MCs) and inhibitory internal granule cells (IGCs), but the physiological mechanisms and behavioral conditions driving this plasticity remain unclear. Here, we report studies of AOB neuronal plasticity following male–male social chemosensory encounters. We show that the plasticity-associated immediate-early gene Arc is selectively expressed in IGCs from resident males following the resident–intruder assay. After behavior, Arc-expressing IGCs are more strongly excited by sensory input stimulation and MC activation is suppressed. Arc-expressing IGCs do not show increased excitatory synaptic drive but instead show increased intrinsic excitability. These data indicate that MC–IGC plasticity is induced after male–male social chemosensory encounters, resulting in enhanced MC suppression by Arc-expressing IGCs. PMID:28659282

  7. Evaluation of Absolute and Relative Reinforcer Value Using Progressive-Ratio Schedules

    PubMed Central

    Francisco, Monica T; Borrero, John C; Sy, Jolene R

    2008-01-01

    We evaluated behavior exhibited by individuals with developmental disabilities using progressive-ratio (PR) schedules. High- and low-preference stimuli were determined based on the results of a paired-stimulus preference assessment and were evaluated in subsequent reinforcer and PR assessments using concurrent and single schedules of presentation. In Experiment 1, results showed that for 2 of 3 participants, stimuli determined to be low-preference functioned as reinforcers when evaluated independent of high-preference stimuli. Further, the results from Experiment 2 showed that low-preference stimuli also functioned as reinforcers under gradually increasing PR requirements. Results suggest that for cases in which a high-preference stimulus is unavailable or impractical, the contingent delivery of relatively less preferred stimuli may maintain appropriate behavior, even as schedule requirements increase. PMID:18595283

  8. Nonword repetition priming in lexical decision reverses as a function of study task and speed stress.

    PubMed

    Zeelenberg, René; Wagenmakers, Eric-Jan; Shiffrin, Richard M

    2004-01-01

    The authors argue that nonword repetition priming in lexical decision is the net result of 2 opposing processes. First, repeating nonwords in the lexical decision task results in the storage of a memory trace containing the interpretation that the letter string is a nonword; retrieval of this trace leads to an increase in performance for repeated nonwords. Second, nonword repetition results in increased familiarity, making the nonword more "wordlike," leading to a decrease in performance. Consistent with this dual-process account, Experiment 1 showed a facilitatory effect for nonwords studied in a lexical decision task but an inhibitory effect for nonwords studied in a letter-height task. Experiment 2 showed inhibitory nonword repetition priming for participants tested under speed-stress instructions. ((c) 2004 APA, all rights reserved)

  9. Grain boundary stability and influence on ionic conductivity in a disordered perovskite -- a first-principles investigation of lithium lanthanum titanate

    DOE PAGES

    Alexander, Kathleen C.; Ganesh, P.; Chi, Miaofang; ...

    2016-12-01

    The origin of ionic conductivity in bulk lithium lanthanum titanate, a promising solid electrolyte for Li-ion batteries, has long been under debate, with experiments showing lower conductivity than predictions. Recent microscopy images show Type I and Type II grain boundaries. Using first-principles based calculations we find that experimentally observed Type I boundaries are more stable compared to the Type II grain boundaries, consistent with their observed relative abundance. Grain boundary stability appears to strongly anti-correlate with the field strength as well as the spatial extent of the space charge region. Ion migration is faster along Type II grain boundaries thanmore » across, consistent with recent experiments of increased conductivity when Type II densities were increased.« less

  10. Operator learning effects in teleoperated rendezvous & docking

    NASA Astrophysics Data System (ADS)

    Wilde, M.; Harder, J.; Purschke, R.

    Teleoperation of spacecraft proximity operations and docking requires delicate timing and coordination of spacecraft maneuvers. Experience has shown that human operators show large performance fluctuations in these areas, which are a major factor to be addressed in operator training. In order to allow the quantification of the impact of these human fluctuations on control system performance and the human perception of this performance, a learning curve study was conducted with teleoperated final approach and docking scenarios. Over a period of ten experiment days, three test participants were tasked with repeatedly completing a set of three training scenarios. The scenarios were designed to contain different combinations of the major elements of any final approach and docking situation, and to feature an increasing difficulty level. The individual difficulty levels for the three operators furthermore differed in the level of operator support functions available in their human-machine interfaces. Operator performance in the test scenarios were evaluated in the fields approach success and precision, docking safety, and approach efficiency by a combination of recorded maneuver data and questionnaires. The results show that operator experience and the associated learning curves increase operator performance substantially, regardless of the support system used. The paper also shows that the fluctuations in operator performance and self-perception are substantial between as well as within experiment days, and must be reckoned with in teleoperation system design and mission planning.

  11. Effect of modified atmosphere packaging and temperature abuse on flavor related volatile compounds of rocket leaves (Diplotaxis tenuifolia L.).

    PubMed

    Mastrandrea, Leonarda; Amodio, Maria Luisa; Pati, Sandra; Colelli, Giancarlo

    2017-07-01

    The effect of storage conditions on flavor-related volatile composition of wild rocket ( Diplotaxis tenuifolia ) was investigated on Modified Atmosphere packed (MAP) leaves stored under isothermal and non-isothermal conditions. In a first experiment the effect of MAP was compared to the storage in air at 5 °C; a second experiment aimed to study the effect of non isothermal conditions, with two temperature abuses (at 13 °C for 24 h) during a 5 °C. Twenty-four volatiles were detected, including C6, C5, isothiocyanate, lipid-derived and sulfur compounds. In the first experiment, MAP-stored rocket showed a slower loss of typical flavour volatiles (thiocyanates and isothiocyanates) and a slower production of off-flavors until 6 days of storage, compared to leaves stored in air. After this time, dimethyl sulfide and acetaldehyde dramatically increased in MAP-stored rocket samples. In the second experiment, samples stored under non-isothermal conditions showed lower O 2 and higher CO 2 concentrations than samples stored under isothermal conditions. Rocket leaves stored under non-isothermal conditions showed an increased production of volatiles responsible of off-flavors (acetaldehyde and dimethyl sulfide) following temperature abuse comparing to storage in isothermal condition. Thus, dimethyl sulfide and acetaldehyde could be effective markers for tracking the effect of temperature fluctuations on rocket during storage.

  12. Transitioning EEG experiments away from the laboratory using a Raspberry Pi 2.

    PubMed

    Kuziek, Jonathan W P; Shienh, Axita; Mathewson, Kyle E

    2017-02-01

    Electroencephalography (EEG) experiments are typically performed in controlled laboratory settings to minimise noise and produce reliable measurements. These controlled conditions also reduce the applicability of the obtained results to more varied environments and may limit their relevance to everyday situations. Advances in computer portability may increase the mobility and applicability of EEG results while decreasing costs. In this experiment we show that stimulus presentation using a Raspberry Pi 2 computer provides a low cost, reliable alternative to a traditional desktop PC in the administration of EEG experimental tasks. Significant and reliable MMN and P3 activity, typical event-related potentials (ERPs) associated with an auditory oddball paradigm, were measured while experiments were administered using the Raspberry Pi 2. While latency differences in ERP triggering were observed between systems, these differences reduced power only marginally, likely due to the reduced processing power of the Raspberry Pi 2. An auditory oddball task administered using the Raspberry Pi 2 produced similar ERPs to those derived from a desktop PC in a laboratory setting. Despite temporal differences and slight increases in trials needed for similar statistical power, the Raspberry Pi 2 can be used to design and present auditory experiments comparable to a PC. Our results show that the Raspberry Pi 2 is a low cost alternative to the desktop PC when administering EEG experiments and, due to its small size and low power consumption, will enable mobile EEG experiments unconstrained by a traditional laboratory setting. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. The malleability of developmental trends in neutral and negative memory illusions.

    PubMed

    Otgaar, Henry; Howe, Mark L; Brackmann, Nathalie; Smeets, Tom

    2016-01-01

    Among many legal professionals and memory researchers there exists the assumption that susceptibility to false memory decreases with age. In 4 misinformation experiments, we show that under conditions that focus on the meaning of experiences, children are not always the most susceptible to suggestion-induced false memories. We begin by presenting a short overview of previous developmental false memory studies, the majority of which have found that the susceptibility to misinformation decreases with age. In Experiment 1, 6/7-year-olds, 11/12-year-olds, and adults received a video and were confronted with misinformation about related but nonpresented details. Older children and adults had higher misinformation acceptance rates than younger children. In Experiment 2, we replicated this finding adding a younger child group (4/6-year-olds). In Experiments 3 and 4, we used new material and again found that susceptibility to misinformation increased with age. Together, these experiments show that children's memory accuracy is not necessarily inferior to that of adults.' (c) 2015 APA, all rights reserved).

  14. The Malleability of Developmental Trends in Neutral and Negative Memory Illusions

    PubMed Central

    2016-01-01

    Among many legal professionals and memory researchers there exists the assumption that susceptibility to false memory decreases with age. In 4 misinformation experiments, we show that under conditions that focus on the meaning of experiences, children are not always the most susceptible to suggestion-induced false memories. We begin by presenting a short overview of previous developmental false memory studies, the majority of which have found that the susceptibility to misinformation decreases with age. In Experiment 1, 6/7-year-olds, 11/12-year-olds, and adults received a video and were confronted with misinformation about related but nonpresented details. Older children and adults had higher misinformation acceptance rates than younger children. In Experiment 2, we replicated this finding adding a younger child group (4/6-year-olds). In Experiments 3 and 4, we used new material and again found that susceptibility to misinformation increased with age. Together, these experiments show that children’s memory accuracy is not necessarily inferior to that of adults.’ PMID:26709588

  15. Neural mechanisms underlying ecstasy-related attentional bias.

    PubMed

    Roberts, Gloria M P; Garavan, Hugh

    2013-08-30

    Conditioned responses to cues associated with drug taking play a pivotal role in a number of theories of drug addiction. This study examined whether attentional biases towards drug-related cues exist in recreational drug users who predominantly used ecstasy (3,4-methylenedioxymethamphetamine). Experiment 1 compared 30 ecstasy users, 25 cannabis users, and 30 controls in an attentional distraction task in which neutral, evocative, and ecstasy-related pictures were presented within a coloured border, requiring participants to respond as quickly as possible to the border colour. Experiment 2 employed functional magnetic resonance imaging (fMRI) and the attentional distraction task and tested 20 ecstasy users and 20 controls. Experiment 1 revealed significant response speed interference by the ecstasy-related pictures in the ecstasy users only. Experiment 2 revealed increased prefrontal and occipital activity in ecstasy users in all conditions. Activations in response to the ecstasy stimuli in these regions showed an apparent antagonism whereby ecstasy users, relative to controls, showed increased occipital but decreased right prefrontal activation. These results are interpreted to reflect increased visual processing of, and decreased prefrontal control over, the irrelevant but salient ecstasy-related stimuli. These results suggest that right inferior frontal cortex may play an important role in controlling drug-related attentional biases and may thus play an important role in mediating control over drug usage. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  16. Impact of water repellency on infiltration of differently concentrated ethanol solutions

    NASA Astrophysics Data System (ADS)

    Dlapa, Pavel; Hrabovský, Andrej; Hriník, Dávid; Kuric, Peter

    2017-04-01

    Infiltration experiments were carried out on an extremely (WDPT > 3600 s) water repellent forest soil in the Little Carpathians Mts (SW Slovakia). Measurements were performed following a long dry warm period using the Mini Disk Infiltrometer (Decagon). Replicated infiltration experiments were conducted with water and five different ethanol solutions. The infiltrometer was set to a capillary pressure head of -2 cm and filled with solutions containing 0, 5, 10, 20, 40, and 95% of ethanol by volume, respectively. Solutions used in infiltration experiments differed in density, viscosity, and surface tension. Combined effect of solution properties on infiltration into soil is strongly dependent on soil surface properties. This may lead to a decrease of infiltration rate with increasing ethanol concentration. Such behaviour should be observable in wettable soils. However, the infiltration experiments revealed a significant increase in the rate of infiltration for increasing concentrations of ethanol. The solutions showed infiltration rates of 10-4, 10-3, and 10-2 cm/s for the 5, 20, and 95% ethanol solutions, respectively. This trend suggests the dominant influence of contact angle (affected by ethanol concentration) on infiltration process. Measurements allow quantifying changes of various infiltration parameters as a function of the solution properties. The obtained results showed that similar approach can be a valuable alternative to other methods used for the evaluation of severity of soil repellency and impacts to hydrological processes.

  17. The financial costs of sadness.

    PubMed

    Lerner, Jennifer S; Li, Ye; Weber, Elke U

    2013-01-01

    We hypothesized a phenomenon that we term myopic misery. According to our hypothesis, sadness increases impatience and creates a myopic focus on obtaining money immediately instead of later. This focus, in turn, increases intertemporal discount rates and thereby produces substantial financial costs. In three experiments, we randomly assigned participants to sad- and neutral-state conditions, and then offered intertemporal choices. Disgust served as a comparison condition in Experiments 1 and 2. Sadness significantly increased impatience: Relative to median neutral-state participants, median sad-state participants accepted 13% to 34% less money immediately to avoid waiting 3 months for payment. In Experiment 2, impatient thoughts mediated the effects. Experiment 3 revealed that sadness made people more present biased (i.e., wanting something immediately), but not globally more impatient. Disgusted participants were not more impatient than neutral participants, and that lack of difference implies that the same financial effects do not arise from all negative emotions. These results show that myopic misery is a robust and potentially harmful phenomenon.

  18. Alpha and gamma band oscillations index differential processing of acoustically reduced and full forms.

    PubMed

    Drijvers, Linda; Mulder, Kimberley; Ernestus, Mirjam

    2016-02-01

    Reduced forms like yeshay for yesterday often occur in conversations. Previous behavioral research reported a processing advantage for full over reduced forms. The present study investigated whether this processing advantage is reflected in a modulation of alpha (8-12Hz) and gamma (30+Hz) band activity. In three electrophysiological experiments, participants listened to full and reduced forms in isolation (Experiment 1), sentence-final position (Experiment 2), or mid-sentence position (Experiment 3). Alpha power was larger in response to reduced forms than to full forms, but only in Experiments 1 and 2. We interpret these increases in alpha power as reflections of higher auditory cognitive load. In all experiments, gamma power only increased in response to full forms, which we interpret as showing that lexical activation spreads more quickly through the semantic network for full than for reduced forms. These results confirm a processing advantage for full forms, especially in non-medial sentence position. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Sensitivity of LES results from turbine rim seals to changes in grid resolution and sector size

    NASA Astrophysics Data System (ADS)

    O'Mahoney, T.; Hills, N.; Chew, J.

    2012-07-01

    Large-Eddy Simulations (LES) were carried out for a turbine rim seal and the sensitivity of the results to changes in grid resolution and the size of the computational domain are investigated. Ingestion of hot annulus gas into the rotor-stator cavity is compared between LES results and against experiments and Unsteady Reynolds-Averaged Navier-Stokes (URANS) calculations. The LES calculations show greater ingestion than the URANS calculation and show better agreement with experiments. Increased grid resolution shows a small improvement in ingestion predictions whereas increasing the sector model size has little effect on the results. The contrast between the different CFD models is most stark in the inner cavity, where the URANS shows almost no ingestion. Particular attention is also paid to the presence of low frequency oscillations in the disc cavity. URANS calculations show such low frequency oscillations at different frequencies than the LES. The oscillations also take a very long time to develop in the LES. The results show that the difficult problem of estimating ingestion through rim seals could be overcome by using LES but that the computational requirements were still restrictive.

  20. Altered brain long-range functional interactions underlying the link between aberrant self-experience and self-other relationship in first-episode schizophrenia.

    PubMed

    Ebisch, Sjoerd J H; Mantini, Dante; Northoff, Georg; Salone, Anatolia; De Berardis, Domenico; Ferri, Francesca; Ferro, Filippo M; Di Giannantonio, Massimo; Romani, Gian L; Gallese, Vittorio

    2014-09-01

    Self-experience anomalies are elementary features of schizophrenic pathology. Such deficits can have a profound impact on self-other relationship, but how they are related through aberrant brain function remains poorly understood. In this functional magnetic resonance imaging (fMRI) study, we provide new evidence for a cortical link between aberrant self-experience and social cognition in first-episode schizophrenia (FES). As identified in previous studies, ventral premotor cortex (vPMC) and posterior insula (pIC) are candidate brain regions underlying disturbances in both self-experience and self-other relationship due to their processing of predominantly externally guided (vPMC; goal-oriented behavior) and internally guided (pIC; interoception) stimuli. Results from functional interaction analysis in a sample of 24 FES patients and 22 healthy controls show aberrant functional interactions (background/intrinsic connectivity) of right vPMC and bilateral pIC with posterior cingulate cortex (PCC), a midline region that has been shown central in mediating self-experience. More specifically, our results show increased functional coupling between vPMC and PCC, which positively correlated with basic symptoms (subjective self-experience disturbances). pIC showed reduced functional coupling with PCC and postcentral gyrus and increased functional interactions with anterior insula. Taken together, our results suggest an imbalance in the processing between internally and externally guided information and its abnormal integration with self-referential processing as mediated by PCC. Due to our correlation findings, we suggest this imbalance to be closely related to basic symptoms in FES and thus anomalous self-experience. The findings further disentangle the cortical basis of how self-experience anomalies may pervade the social domain. © The Author 2013. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  1. Utilization of rice-husk and coconut shell carbons for water disinfection.

    PubMed

    Carmalin Sophia, A; Catherine, D; Bhalambaal, V M

    2013-01-01

    In the present study, experiments were conducted to investigate the feasibility of using carbon derived from rice husk and coconut shell for the decontamination of water containing Escherichia coli (E. coli). The effects of silver impregnation on these agro-waste carbons were also investigated. All the carbons showed >99% removal of E coli. Among the four carbons studied, rice husk based carbon (RHC) showed better removal than the other carbons investigated. However, silver impregnated carbons showed only marginal increase in the decontamination experiments. SEM and BET results reveal that the carbons were mesoporous in nature. FTIR shows the presence of functional groups viz. C=O and -OH that might be responsible.for adsorption of E. coli on the carbon.

  2. Long-term effects of neonatal medial temporal ablations on socioemotional behavior in monkeys (Macaca mulatta).

    PubMed

    Malkova, Ludise; Mishkin, Mortimer; Suomi, Stephen J; Bachevalier, Jocelyne

    2010-12-01

    Socioemotional abnormalities, including decreased social interactions and increased self-directed activity, were reported when rhesus monkeys with neonatal ablations of either the medial temporal lobe (AH) or the inferior temporal cortex (TE) were paired with unoperated peers at two and six months of age, though these abnormalities were more severe in Group AH (Bachevalier et al., 2001). As adults (Experiment 1), the monkeys were re-evaluated in the same dyads and their reactivity to novel toys, social status, and reactions to separation were also assessed. Group TE now showed only few if any of the abnormal behaviors observed in infancy. In contrast, Group AH continued to display decreased social interactions and increased self-directed activity and showed also increased submission and reduced responses to separation, but normal reactivity to novel toys. To determine whether this degree of socioemotional impairment was less severe than that produced by the same damage in adulthood, we assessed dyadic social interactions of monkeys raised until adulthood in laboratory conditions similar to those in Experiment 1 and then given the AH ablations (Experiment 2). Two months postoperatively these monkeys showed a small reduction in social interactions that became more pronounced six months postoperatively, yet remained less severe than that seen in the infant-lesioned monkeys. No other socioemotional effects, except for an increase in food/water consumption, were observed. The finding that neonatal AH lesions produce more severe socioemotional disturbances than the same lesion in adulthood is the reverse of the effect commonly reported for other cognitive functions after cerebral damage. © 2010 APA, all rights reserved.

  3. Use of high metal-containing biogas digestates in cereal production - Mobility of chromium and aluminium.

    PubMed

    Dragicevic, Ivan; Eich-Greatorex, Susanne; Sogn, Trine A; Horn, Svein J; Krogstad, Tore

    2018-07-01

    Biogas digestate use as organic fertilizer has been widely promoted in recent years as a part of the global agenda on recycling waste and new sustainable energy production. Although many studies have confirmed positive effects of digestates on soil fertility, there is still lack of information on the potential adverse effects of digestates on natural soil heavy metal content, metal leaching and leaching of other pollutants. We have investigated the release of aluminium (Al) and chromium (Cr) from different soils treated with commercial digestates high in mentioned potentially problematic metals in a field experiment, while a greenhouse and a laboratory column experiment were used to address mobility of these metals in two other scenarios. Results obtained from the field experiment showed an increase in total concentrations for both investigated metals on plots treated with digestates as well as a significant increase of water-soluble Al concentrations. Factors that were found to be mostly affecting the metal mobility were dissolved organic carbon (DOC), pH and type of soil. Metal binding and free metal concentrations were modelled using the WHAM 7.0 software. Results indicated that the use of digestates with high metal content are comparable to use of animal manure with respect to metal leaching. Data obtained through chemical modelling for the samples from the field experiment suggested that an environmental risk from higher metal mobility has to be considered for Al. In the greenhouse experiment, measured concentrations of leached Cr at the end of the growing season were low for all treatments, while the concentration of leached Al from digestates was higher. The high irrigation column leaching experiment showed an increased leaching rate of Cr with addition of digestates. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Effects of Intoxicating Free-Choice Alcohol Consumption During Adolescence on Drinking and Impulsivity During Adulthood in Selectively Bred High Alcohol Preferring Mice

    PubMed Central

    O’Tousa, David Scott; Matson, Liana Marie; Grahame, Nicholas Joseph

    2014-01-01

    Background Abuse of alcohol during adolescence continues to be a problem, and it has been shown that earlier onset of drinking predicts increased alcohol abuse problems later in life. High levels of impulsivity have been demonstrated to be characteristic of alcoholics, and impulsivity has also been shown to predict later alcohol use in teenage subjects, showing that impulsivity may precede the development of alcohol use disorders. These experiments examined adolescent drinking in a high-drinking, relatively impulsive mouse population, and assessed its effects on adult drinking and adult impulsivity. Methods Experiment 1: Selectively bred High-Alcohol Preferring (HAPII) mice were given either alcohol (free choice access) or water only for two weeks during middle adolescence or adulthood. All mice were given free choice access to alcohol 30 days later, in adulthood. Experiment 2: Adolescent HAPII mice drank alcohol and water, or water alone, for two weeks, and were then trained to perform a delay discounting task as adults to measure impulsivity. In each experiment, effects of volitional ethanol consumption on later behavior were assessed. We expected adolescent alcohol exposure to increase subsequent drinking and impulsivity. Results Mice consumed significant quantities of ethanol, reaching average blood ethanol concentrations (BECs) of 142 mg/dl (adolescent) or 154 mg/dl (adult) in Experiment 1. Adolescent mice in experiment 2 reached an average of 108 mg/dl. Mice exposed to alcohol in either adolescence or adulthood showed a transient increase in ethanol consumption, but we observed no differences in impulsivity in adult mice as a function of whether mice drank alcohol during adolescence. Conclusions These findings indicate that HAPII mice drink intoxicating levels of alcohol during both adolescence and adulthood, and that this volitional intake has long-term effects on subsequent drinking behavior. Nonetheless, this profound exposure to alcohol during adolescence does not increase impulsivity in adulthood, indicating that long-term changes in drinking are mediated by mechanisms other than impulsivity. PMID:22725646

  5. A comprehensive test of evolutionarily increased competitive ability in a highly invasive plant species.

    PubMed

    Joshi, Srijana; Gruntman, Michal; Bilton, Mark; Seifan, Merav; Tielbörger, Katja

    2014-12-01

    A common hypothesis to explain plants' invasive success is that release from natural enemies in the introduced range selects for reduced allocation to resistance traits and a subsequent increase in resources available for growth and competitive ability (evolution of increased competitive ability, EICA). However, studies that have investigated this hypothesis have been incomplete as they either did not test for all aspects of competitive ability or did not select appropriate competitors. Here, the prediction of increased competitive ability was examined with the invasive plant Lythrum salicaria (purple loosestrife) in a set of common-garden experiments that addressed these aspects by carefully distinguishing between competitive effect and response of invasive and native plants, and by using both intraspecific and interspecific competition settings with a highly vigorous neighbour, Urtica dioica (stinging nettle), which occurs in both ranges. While the intraspecific competition results showed no differences in competitive effect or response between native and invasive plants, the interspecific competition experiment revealed greater competitive response and effect of invasive plants in both biomass and seed production. The use of both intra- and interspecific competition experiments in this study revealed opposing results. While the first experiment refutes the EICA hypothesis, the second shows strong support for it, suggesting evolutionarily increased competitive ability in invasive populations of L. salicaria. It is suggested that the use of naturally co-occurring heterospecifics, rather than conspecifics, may provide a better evaluation of the possible evolutionary shift towards greater competitive ability. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Minimal groups increase young children's motivation and learning on group-relevant tasks.

    PubMed

    Master, Allison; Walton, Gregory M

    2013-01-01

    Three experiments (N = 130) used a minimal group manipulation to show that just perceived membership in a social group boosts young children's motivation for and learning from group-relevant tasks. In Experiment 1, 4-year-old children assigned to a minimal "puzzles group" persisted longer on a challenging puzzle than children identified as the "puzzles child" or children in a control condition. Experiment 2 showed that this boost in motivation occurred only when the group was associated with the task. In Experiment 3, children assigned to a minimal group associated with word learning learned more words than children assigned an analogous individual identity. The studies demonstrate that fostering shared motivations may be a powerful means by which to shape young children's academic outcomes. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

  7. What speeds up the internal clock? Effects of clicks and flicker on duration judgements and reaction time.

    PubMed

    Wearden, J H; Williams, Emily A; Jones, Luke A

    2017-03-01

    Four experiments investigated the effect of pre-stimulus events on judgements of the subjective duration of tones that they preceded. Experiments 1 to 4 used click trains, flickering squares, expanding circles, and white noise as pre-stimulus events and showed that (a) periodic clicks appeared to "speed up" the pacemaker of an internal clock but that the effect wore off over a click-free delay, (b) aperiodic click trains, and visual stimuli in the form of flickering squares and expanding circles, also produced similar increases in estimated tone duration, as did white noise, although its effect was weaker. A fifth experiment examined the effects of periodic flicker on reaction time and showed that, as with periodic clicks in a previous experiment, reaction times were shorter when preceded by flicker than without.

  8. How Does Context Play "a Part" in Splitting Words "Apart"? Production and Perception of Word Boundaries in Casual Speech

    ERIC Educational Resources Information Center

    Kim, Dahee; Stephens, Joseph D. W.; Pitt, Mark A.

    2012-01-01

    Four experiments examined listeners' segmentation of ambiguous schwa-initial sequences (e.g., "a long" vs. "along") in casual speech, where acoustic cues can be unclear, possibly increasing reliance on contextual information to resolve the ambiguity. In Experiment 1, acoustic analyses of talkers' productions showed that the one-word and two-word…

  9. Minimal Groups Increase Young Children's Motivation and Learning on Group-Relevant Tasks

    ERIC Educational Resources Information Center

    Master, Allison; Walton, Gregory M.

    2013-01-01

    Three experiments ("N" = 130) used a minimal group manipulation to show that just perceived membership in a social group boosts young children's motivation for and learning from group-relevant tasks. In Experiment 1, 4-year-old children assigned to a minimal "puzzles group" persisted longer on a challenging puzzle than children identified as the…

  10. Are Psychophysical Scales of Intensities the Same or Different when Stimuli Vary on Other Dimensions? Theory with Experiments Varying Loudness and Pitch

    ERIC Educational Resources Information Center

    Luce, R. Duncan; Steingrimsson, Ragnar; Narens, Louis

    2010-01-01

    Most studies concerning psychological measurement scales of intensive attributes have concluded that these scales are of ratio type and that the psychophysical function is closely approximated by a power function. Experiments show, for such cases, that a commutativity property must hold under either successive increases or successive decreases…

  11. Investigating the Effects of Multimodal Feedback through Tracking State in Pen-Based Interfaces

    ERIC Educational Resources Information Center

    Sun, Minghui; Ren, Xiangshi

    2011-01-01

    A tracking state increases the bandwidth of pen-based interfaces. However, this state is difficult to detect with default visual feedback. This paper reports on two experiments that are designed to evaluate multimodal feedback for pointing tasks (both 1D and 2D) in tracking state. In 1D pointing experiments, results show that there is a…

  12. Comparison of Model and Observed Regional Temperature Changes During the Past 40 Years

    NASA Technical Reports Server (NTRS)

    Russell, Gary L.; Miller, James R.; Rind, David; Ruedy, Reto A.; Schmidt, Gavin A.; Sheth, Sukeshi

    1999-01-01

    Results are presented for six simulations of the Goddard Institute for Space Studies (GISS) global atmosphere-ocean model for the years 1950 to 2099. There are two control simulations with constant 1950 atmospheric composition from different initial states, two GHG experiments with observed greenhouse gases up to 1990 and compounded .5% CO2 annual increases thereafter, and two GHG+SO4 experiments with the same varying greenhouse gases plus varying tropospheric sulfate aerosols. Surface air temperature trends in the two GHG experiments are compared between themselves and with the observed temperature record from 1960 and 1998. All comparisons show high positive spatial correlation in the northern hemisphere except in summer when the greenhouse signal is weakest. The GHG+SO4 experiments show weaker correlations. In the southern hemisphere, correlations are either weak or negative which in part are due to the model's unrealistic interannual variability of southern sea ice cover. The model results imply that temperature changes due to forcing by increased greenhouse gases have risen above the level of regional interannual temperature variability in the northern hemisphere over the past 40 years. This period is thus an important test of reliability of coupled climate models.

  13. Practice on improving fattening local cattle production in Vietnam by increasing crude protein level in concentrate and concentrate level.

    PubMed

    Van Dung, Dinh; Ba, Nguyen Xuan; Van, Nguyen Huu; Phung, Le Dinh; Ngoan, Le Duc; Cuong, Vu Chi; Yao, Wen

    2013-10-01

    Two experiments were conducted to determine the effects of crude protein (CP) level in concentrate (experiment 1) and concentrate level (experiment 2) on feed intake, nutrient digestibility, nitrogen (N) retention, ruminal pH and NH3-N concentration and average daily gain (ADG) of Vietnamese local fattening cattle. Animals (24 cattle, initial live weight (LW) 150.3 ± 11.8 kg in experiment 1 and 145.1 ± 9.8 kg in experiment 2) were allotted based on LW to one of four treatments in a randomised complete block design. In experiment 1, concentrate with four levels of CP (10, 13, 16 and 19 %) was fed at 1.5 % of LW. In experiment 2, concentrate was fed at 1.0, 1.4, 1.8 and 2.2 % of LW. In both experiments, roughage was 5 kg/day native grass and ad libitum rice straw (fresh basis). Results showed that the CP level in concentrate significantly affected dry matter (DM) intake (P < 0.05), N retention, ADG and ruminal NH3-N concentration (P < 0.01), but it had no significant effect on DM, organic matter (OM) and neutral detergent fibre (NDF) digestibility (P > 0.05), whereas CP digestibility increased (P < 0.001) along with the CP level. DM intake, N retention and ADG increased (P < 0.001) linearly with concentrate intake. DM and CP digestibility were not significantly affected by concentrate intake (P > 0.05). OM digestibility and NH3-N concentration increased linearly (P < 0.05), whereas NDF digestibility and ruminal pH declined linearly with increased concentrate consumption (P < 0.01). These results indicate that 16 % CP in concentrate and feeding concentrate at the rate of 2.2 % of LW are recommendable for fattening local cattle in Vietnam.

  14. Influence of intramuscular fat content on the quality of pig meat - 2. Consumer acceptability of m. longissimus lumborum.

    PubMed

    Fernandez, X; Monin, G; Talmant, A; Mourot, J; Lebret, B

    1999-09-01

    The present study is part of a project which aimed to examine the influence of intramuscular fat (IMF) content on sensory attributes and consumer acceptability of pork. Two experiments were conducted to evaluate consumer acceptability of pork chops with varying IMF level in muscle Longissimus lumborum (LL). Each experiment used 32 castrated male pigs selected after slaughter either from 125 Duroc × Landrace (Experiment 1) or 102 Tia Meslan × Landrace (Experiment 2) crossbred animals, and showing large variability in LL IMF content: from <1.5 to >3.5% in Experiment 1 and from 1.25 to 3.25% in Experiment 2. A group of 56 consumers evaluated various items on rib-eye (LL muscle trimmed of backfat) (Experiment 1) and on entire chops trimmed of backfat (Experiment 2). Data from Experiment 1 indicate that an increase in IMF level is associated with an increase in visual perception of fat and a corresponding decrease in the willingness to eat and purchase the meat, when expressed before tasting. The latter effect disappeared after the consumers had tasted the meat, probably due to a positive effect of increase IMF, up to 3.5%, on the perception of texture and taste. In Experiment 2, where entire chops were evaluated, the perception of visible fat was not affected by IMF level, probably due to the lack of variation in the level of intermuscular fat between the four IMF groups. The willingness to eat and purchase the meat were unaffected by IMF level, whereas the perception of texture and taste was enhanced with increased IMF levels up to 3.25%. The present data suggest that the acceptability of pork may be improved by increasing IMF level but: (1) this effect disappeared for IMF levels higher than 3.5%, which are associated with a high risk of meat rejection due to visible fat and (2) the positive effect of increased IMF probably holds true as long as it is not associated with an increase in the level of intermuscular fat.

  15. Mecp2 Mediates Experience-Dependent Transcriptional Upregulation of Ryanodine Receptor Type-3

    PubMed Central

    Torres, Rodrigo F.; Hidalgo, Cecilia; Kerr, Bredford

    2017-01-01

    Mecp2 is a DNA methylation reader that plays a critical role in experience-dependent plasticity. Increasing evidence supports a role for epigenetic modifications in activity-induced gene expression. Hence, candidate genes related to such phenomena are of great interest. Ryanodine receptors are intracellular calcium channels that contribute to hippocampal synaptic plasticity, dendritic spine remodeling, and participate in learning and memory processes. Here we exposed mice to the enriched environment (EE) paradigm, which through increased stimulation induces experience dependent-plasticity, to explore a role for methyl-cytosines, and Mecp2 in directing Ryanodine receptor 3 (Ryr3) transcriptional activity. EE induced a hippocampal-specific increase in the methylation of discrete cytosines located at a Ryr3 isoform promoter; chromatin immunoprecipitation experiments revealed that EE increased Mecp2 binding to this Ryr3 isoform promoter. Interestingly, the experimental paradigm induced robust Ryr3 upregulation, accompanied by miR132-dependent suppression of p250GAP, a pathway driving synaptogenesis. In contrast to WT mice, Mecp2-null mice showed diminished levels of Ryr3 and displayed impaired EE-induced Ryr3 upregulation, compromising miR132 dependent suppression of p250GAP and experience-dependent structural plasticity. Based on these results, we propose that Mecp2 acts as a transcriptional activator of Ryr3, contributing to experience-dependent plasticity. PMID:28659760

  16. Trauma-Related Dissociation Is Linked With Maladaptive Personality Functioning

    PubMed Central

    Granieri, Antonella; Guglielmucci, Fanny; Costanzo, Antonino; Caretti, Vincenzo; Schimmenti, Adriano

    2018-01-01

    Background: Extensive research has demonstrated the positive associations among the exposure to traumatic experiences, the levels of dissociation, and the severity of psychiatric symptoms in adults. However, it has been hypothesized in clinical literature that an excessive activation of the dissociative processes following multiple traumatic experiences may jeopardize the psychological and behavioral functioning of the individuals, fostering higher levels of maladaptive personality functioning. Methods: The study involved 322 adult volunteers from Italy. Participants completed measures on traumatic experiences, dissociation, and maladaptive personality traits. Results: The number of traumatic experiences reported by participants were positively associated with dissociation scores and maladaptive personality scores. Mediation analyses showed that dissociation acted as a partial mediator in the relationship between traumatic experiences and overall maladaptive personality functioning. Regression curve analyses showed that the positive association between maladaptive personality functioning and dissociation was stronger among participants with higher exposure to traumatic experiences. Conclusion: Exposure to multiple traumatic experiences may increase the risk for an excessive activation of the dissociative processes, which in turn may generate severe impairments in multiple domains of personality functioning. PMID:29887807

  17. Confinement improvement in the high poloidal beta regime on DIII-D and application to steady-state H-mode on EAST

    DOE PAGES

    Ding, Siye; Garofalo, A. M.; Qian, J.; ...

    2017-05-03

    Systematic experimental and modeling investigations on DIII-D and EAST show attractive transport properties of fully non-inductive high β p plasmas. Experiments on DIII-D show that the large-radius internal transport barrier (ITB), a key feature providing excellent confinement in the high β p regime, is maintained when the scenario is extended from q 95 ~ 12 to 7 and from rapid to near-zero toroidal rotation. The robustness of confinement versus rotation was predicted by gyro fluid modeling showing dominant neoclassical ion energy transport even without E B shear effect. The physics mechanism of turbulence suppression, we found, is the Shafranov shift,more » which is essential and sets a β p threshold for large-radius ITB formation in the high β p scenario on DIII-D. This is confirmed by two different parameter-scan experiments, one for β N scan and the other for q 95 scan. They both give the same p threshold at 1.9 in the experiment. Furthermore, the experiment trend of increasing thermal transport with decreasing β p is consistent with transport modeling. The very first step of extending high β p scenario on DIII-D to long pulse on EAST is to establish long pulse H-mode with ITB on EAST. Our paper shows the first 61 sec fully non-inductive H-mode with stationary ITB feature and actively cooled ITER-like tungsten divertor in the very recent EAST experiment. The successful use of lower hybrid wave (LWH) as a key tool to optimize current profile in EAST experiment is also introduced. Results show that as the electron density is increased, the fully non-inductive current profile broadens on EAST. The improved understanding and modeling capability is also used to develop advanced scenarios for CFETR. These results provide encouragement that the high β p regime can be extended to lower safety factor and very low rotation, providing a potential path to high performance steady state operation in future devices.« less

  18. Confinement improvement in the high poloidal beta regime on DIII-D and application to steady-state H-mode on EAST

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

    Ding, Siye; Garofalo, A. M.; Qian, J.

    Systematic experimental and modeling investigations on DIII-D and EAST show attractive transport properties of fully non-inductive high β p plasmas. Experiments on DIII-D show that the large-radius internal transport barrier (ITB), a key feature providing excellent confinement in the high β p regime, is maintained when the scenario is extended from q 95 ~ 12 to 7 and from rapid to near-zero toroidal rotation. The robustness of confinement versus rotation was predicted by gyro fluid modeling showing dominant neoclassical ion energy transport even without E B shear effect. The physics mechanism of turbulence suppression, we found, is the Shafranov shift,more » which is essential and sets a β p threshold for large-radius ITB formation in the high β p scenario on DIII-D. This is confirmed by two different parameter-scan experiments, one for β N scan and the other for q 95 scan. They both give the same p threshold at 1.9 in the experiment. Furthermore, the experiment trend of increasing thermal transport with decreasing β p is consistent with transport modeling. The very first step of extending high β p scenario on DIII-D to long pulse on EAST is to establish long pulse H-mode with ITB on EAST. Our paper shows the first 61 sec fully non-inductive H-mode with stationary ITB feature and actively cooled ITER-like tungsten divertor in the very recent EAST experiment. The successful use of lower hybrid wave (LWH) as a key tool to optimize current profile in EAST experiment is also introduced. Results show that as the electron density is increased, the fully non-inductive current profile broadens on EAST. The improved understanding and modeling capability is also used to develop advanced scenarios for CFETR. These results provide encouragement that the high β p regime can be extended to lower safety factor and very low rotation, providing a potential path to high performance steady state operation in future devices.« less

  19. Effect of descriptive information and experience on automation reliance.

    PubMed

    Yuviler-Gavish, Nirit; Gopher, Daniel

    2011-06-01

    The present research addresses the issue of reliance on decision support systems for the long-term (DSSLT), which help users develop decision-making strategies and long-term planning. It is argued that providing information about a system's future performance in an experiential manner, as compared with a descriptive manner, encourages users to increase their reliance level. Establishing appropriate reliance on DSSLT is contingent on the system developer's ability to provide users with information about the system's future performance. A sequence of three studies contrasts the effect on automation reliance of providing descriptive information versus experience for DSSLT with two different positive expected values of recommendations. Study I demonstrated that when automation reliance was determined solely on the basis of description, it was relatively low, but it increased significantly when a decision was made after experience with 50 training simulations. Participants were able to learn to increase their automation reliance levels when they encountered the same type of recommendation again. Study 2 showed that the absence of preliminary descriptive information did not affect the automation reliance levels obtained after experience. Study 3 demonstrated that participants were able to generalize their learning about increasing reliance levels to new recommendations. Using experience rather than description to give users information about future performance in DSSLT can help increase automation reliance levels. Implications for designing DSSLT and decision support systems in general are discussed.

  20. Adrenocortical responses in Japanese quail classified by their permanence in proximity to either low or high density of conspecifics.

    PubMed

    Guzmán, D A; Lèche, A; Contarde, C B; Nazar, F N; Marin, R H

    2018-06-19

    The density-related permanence test (DRP) is used to classify young birds (while in groups) according to their individual permanence in proximity to either a high or low density of conspecifics (HD or LD, respectively). The birds' performance in DRP was associated with underlying differences in the social responses of their individuals. Quails in homogeneous groups of LD residents responded with less compact groups and higher levels of agonistic interactions to the presence of an intruder, and showed higher levels of agonistic interactions among cagemates than the homogeneous groups of HD birds. This study deepen the characterization of DRP evaluating whether contrasting behavior during test is associated with birds' stress responses to challenging situations during rearing. Plasma corticosterone responses were individually assessed after submitting DRP categorized birds to a brief (10 min) partial restraint (mechanical stressor; experiment 1), or after introducing them during 5 min as intruders in homogeneous groups of 6 unknown same category (HD or LD) conspecifics (social stressor; experiment 2). Experiment 1 showed that basal corticosterone levels were similar in all groups and the partial mechanical restraint induced an increase in plasma corticosterone concentration also in all groups. However, the increase induced by the stressor was higher in the LD birds than in their HD counterparts. In experiment 2, compared to controls, social stressor showed no plasma corticosterone changes in the intruders that were introduced in an unfamiliar group of HD conspecifics. However, intruders (both HD and LD) that were visiting the LD residents showed an increased corticosterone response compared to their control counterparts. Results suggest that categorization of birds in the DRP test could have relevance for selection programs oriented to obtain birds better suited to intensive rearing conditions that includes high density of animals and exposure to unavoidable stressors.

  1. The effect of positive writing on emotional intelligence and life satisfaction.

    PubMed

    Wing, Joanna F; Schutte, Nicola S; Byrne, Brian

    2006-10-01

    This study explored the effect of writing about positive emotional experiences on emotional intelligence and life satisfaction. One hundred and seventy-five adults wrote about one of the following three topics: positive experiences with a cue for emotion regulation reflection, positive experiences without this cue, or a control writing topic. Multivariate analysis showed a significant time (pretest, posttest, and follow-up) by group effect. Writing about positive emotional experiences with an emotion regulation cue led to significant increases in emotional intelligence and life satisfaction at posttest and the increase in life satisfaction was maintained at 2-week follow-up. Further, participants who were cued to reflect on emotional regulation while writing about positive experiences rated their emotional intelligence significantly higher than the participants in the control writing group both at posttest and at follow-up. There were no significant differences in emotional intelligence or life satisfaction between those who were cued to reflect on emotional regulation while writing about positive experiences and those who wrote about positive experiences without such a cue. 2006 Wiley Periodicals, Inc.

  2. Study on Elastic Helical TDR Sensing Cable for Distributed Deformation Detection

    PubMed Central

    Tong, Renyuan; Li, Ming; Li, Qing

    2012-01-01

    In order to detect distributed ground surface deformation, an elastic helical structure Time Domain Reflectometry (TDR) sensing cable is shown in this paper. This special sensing cable consists of three parts: a silicone rubber rope in the center; a couple of parallel wires coiling around the rope; a silicone rubber pipe covering the sensing cable. By analyzing the relationship between the impedance and the structure of the sensing cable, the impedance model shows that the sensing cable impedance will increase when the cable is stretched. This specific characteristic is verified in the cable stretching experiment which is the base of TDR sensing technology. The TDR experiment shows that a positive reflected signal is created at the stretching deformation point on the sensing cable. The results show that the deformation section length and the stretching elongation will both affect the amplitude of the reflected signal. Finally, the deformation locating experiments show that the sensing cable can accurately detect the deformation point position on the sensing cable. PMID:23012560

  3. Long-term Ecosystem Experiments, Data Assimilation, and Meta-Analysis

    NASA Astrophysics Data System (ADS)

    Hungate, B. A.; Van Groenigen, K. J.; Osenberg, C. W.; van Gestel, N.

    2015-12-01

    Land ecosystems affect climate and the atmosphere, and climate and atmospheric change affects ecosystems. Syntheses of ecosystem experiments investigating their responses to environmental change holds promise for understanding how to model these interactions, and thereby gain insight into Earth's future biosphere, atmosphere, and climate. Long-term experiments examining ecosystem responses are thought to be especially important in this effort, for their potential to reveal cumulative and progressive effects, subtle effects initially undetectable experimentally, but manifest more clearly over time, often with stronger implications for modeled responses than the more dramatic, short-term experimental responses. Here, we present new analyses of long-term experiments manipulating temperature, CO2 concentration, and precipitation, testing the general hypothesis that there are common temporal patterns of responses that reveal general biogeochemical characterizing ecosystem responses to these environmental changes. For example, we show that increased carbon input with elevated CO2 stimulates emissions of nitrous oxide and methane, important greenhouse gases, and that effects show no signs of diminishing over the duration of experiments that have documented responses. At the same time, we show that the temporal resolution for this response is limited, pointing to a potential limitation in the ability of experiments to address clearly long-term hypotheses. We also show that warming tends to have limited cumulative effects on total soil carbon stocks in long-term experiments, and explore the mechanisms underlying this response. Finally, we discuss the implications of these findings for models used to simulate long-term ecosystem responses to these environmental forcings, as well as the implications of these findings for the next generation of terrestrial ecosystem experiments.

  4. Role of masker predictability in the cocktail party problem1

    PubMed Central

    Jones, Gary L.; Litovsky, Ruth Y.

    2008-01-01

    In studies of the cocktail party problem, the number and locations of maskers are typically fixed throughout a block of trials, which leaves out uncertainty that exists in real-world environments. The current experiments examined whether there is (1) improved speech intelligibility and (2) increased spatial release from masking (SRM), as predictability of the number∕locations of speech maskers is increased. In the first experiment, subjects identified a target word presented at a fixed level in the presence of 0, 1, or 2 maskers as predictability of the masker configuration ranged from 10% to 80%. The second experiment examined speech reception thresholds and SRM as (a) predictability of the masker configuration is increased from 20% to 80% and∕or (b) the complexity of the listening environment is decreased. In the third experiment, predictability of the masker configuration was increased from 20% up to 100% while minimizing the onset delay between maskers and the target. All experiments showed no effect of predictability of the masker configuration on speech intelligibility or SRM. These results suggest that knowing the number and location(s) of maskers may not necessarily contribute significantly to solving the cocktail party problem, at least not when the location of the target is known. PMID:19206808

  5. Experiment study of mud to the moving process influent about viscous debris flow along slope

    NASA Astrophysics Data System (ADS)

    Jun, JiXian; Ying, Liang; Li, Pan Hua; Qiang, OuGuo

    2018-01-01

    Mud is the main component of viscous debris flow. The physical model experiments of viscous debris flow were carried out through the mixing mud with different density and fixed components of coarse particles. The width, longitudinal movement distance and motion velocity were recorded by video cameras during experiment. Through viscous debris flow physical model experiments, the influence of mud to transverse width, longitudinal movement distance and motion velocity was discussed. The physical model experiment results show that the motion forms change from inviscid particle flow to viscous debris flow and to the whole mass sliding with the increase of mud density; the width and the length along the slope decrease with mud density increasing; the movement process has classified phenomena about viscous debris flow composed by different mud densities: the velocity increases rapidly with time and the change gradient is steady when the density of mud is lower than 1.413g/cm3; the movement process can be divided into two stages when the density of mud is higher than 1.413g/cm3: the movement velocity is lower and the gradient change is small in the initial stage; but in the second stage, the movement velocity increases quickly, and the gradient is higher than the first stage, and with steady value.

  6. Observation of >400-eV precursor plasmas from low-wire-number copper arrays at the 1-MA zebra facility.

    PubMed

    Coverdale, C A; Safronova, A S; Kantsyrev, V L; Ouart, N D; Esaulov, A A; Deeney, C; Williamson, K M; Osborne, G C; Shrestha, I; Ampleford, D J; Jones, B

    2009-04-17

    Experiments with cylindrical copper wire arrays at the 1-MA Zebra facility show that high temperatures exist in the precursor plasmas formed when ablated wire array material accretes on the axis prior to the stagnation of a z pinch. In these experiments, the precursor radiated approximately 20% of the >1000 eV x-ray output, and time-resolved spectra show substantial emission from Cu L-shell lines. Modeling of the spectra shows an increase in temperature as the precursor forms, up to approximately 450 eV, after which the temperature decreases to approximately 220-320 eV until the main implosion.

  7. Magnetic properties and magnetocaloric effect in Pt doped Ni-Mn-Ga

    NASA Astrophysics Data System (ADS)

    Singh, Sanjay; D'Souza, S. W.; Mukherjee, K.; Kushwaha, P.; Barman, S. R.; Agarwal, Sandeep; Mukhopadhyay, P. K.; Chakrabarti, Aparna; Sampathkumaran, E. V.

    2014-06-01

    Large magnetocaloric effect is observed in Ni1.8Pt0.2MnGa close to room temperature. The entropy change shows a crossover from positive to negative sign at the martensite transition. It is negative above 1.6 T and its magnitude increases linearly with magnetic field. An increase in the saturation magnetic moment is observed with Pt doping in Ni2MnGa. Ab initio theoretical calculations show that the increase in magnetic moment with Pt doping in Ni2MnGa is associated with increase in the Mn and Pt local moments in the ferromagnetic ground state. The Curie temperature calculated from the exchange interaction parameters is in good agreement with experiment, showing the absence of any antiferromagnetic correlation due to Pt doping.

  8. Dental plaque development on a hydroxyapatite disk in young adults observed by using a barcoded pyrosequencing approach

    PubMed Central

    Takeshita, Toru; Yasui, Masaki; Shibata, Yukie; Furuta, Michiko; Saeki, Yoji; Eshima, Nobuoki; Yamashita, Yoshihisa

    2015-01-01

    Dental plaque is a dynamic microbial biofilm ecosystem that comprises hundreds of species including difficult-to-cultivate bacteria. We observed the assembly of a plaque bacterial community through 16S rRNA gene analysis. Plaque samples that accumulated on a hydroxyapatite disk for 1, 2, 3, 4, 5, and 7 days with saliva on day 0 were collected from 19 young adults using a removable resin splint. Quantitative PCR analysis showed that the total bacterial amount gradually increased and reached a plateau on day 4. Barcoded pyrosequencing analysis revealed that the microbial richness and diversity particularly increased between days 5 and 7. A principal coordinate analysis plot based on unweighted UniFrac showed the community assembly in a time-related manner, which became increasingly similar to the salivary microbiota. Facultative anaerobic bacteria such as Streptococcus, Neisseria, Abiotrophia, Gemella, and Rothia were predominant in the plaque bacterial community in the earlier days, whereas obligate anaerobes, such as Porphyromonas, Fusobacterium, Prevotella, and Capnocytophaga showed increased dominance on later days. UniFrac analysis also demonstrated that dental caries experience had a significant effect on the assembly process. Our results reveal the development pattern of the plaque bacterial community as well as the inter-individual differences associated with dental caries experience. PMID:25633431

  9. Dental plaque development on a hydroxyapatite disk in young adults observed by using a barcoded pyrosequencing approach.

    PubMed

    Takeshita, Toru; Yasui, Masaki; Shibata, Yukie; Furuta, Michiko; Saeki, Yoji; Eshima, Nobuoki; Yamashita, Yoshihisa

    2015-01-30

    Dental plaque is a dynamic microbial biofilm ecosystem that comprises hundreds of species including difficult-to-cultivate bacteria. We observed the assembly of a plaque bacterial community through 16S rRNA gene analysis. Plaque samples that accumulated on a hydroxyapatite disk for 1, 2, 3, 4, 5, and 7 days with saliva on day 0 were collected from 19 young adults using a removable resin splint. Quantitative PCR analysis showed that the total bacterial amount gradually increased and reached a plateau on day 4. Barcoded pyrosequencing analysis revealed that the microbial richness and diversity particularly increased between days 5 and 7. A principal coordinate analysis plot based on unweighted UniFrac showed the community assembly in a time-related manner, which became increasingly similar to the salivary microbiota. Facultative anaerobic bacteria such as Streptococcus, Neisseria, Abiotrophia, Gemella, and Rothia were predominant in the plaque bacterial community in the earlier days, whereas obligate anaerobes, such as Porphyromonas, Fusobacterium, Prevotella, and Capnocytophaga showed increased dominance on later days. UniFrac analysis also demonstrated that dental caries experience had a significant effect on the assembly process. Our results reveal the development pattern of the plaque bacterial community as well as the inter-individual differences associated with dental caries experience.

  10. Tobacco Mosaic Virus Infection Results in an Increase in Recombination Frequency and Resistance to Viral, Bacterial, and Fungal Pathogens in the Progeny of Infected Tobacco Plants1[C][W][OA

    PubMed Central

    Kathiria, Palak; Sidler, Corinne; Golubov, Andrey; Kalischuk, Melanie; Kawchuk, Lawrence M.; Kovalchuk, Igor

    2010-01-01

    Our previous experiments showed that infection of tobacco (Nicotiana tabacum) plants with Tobacco mosaic virus (TMV) leads to an increase in homologous recombination frequency (HRF). The progeny of infected plants also had an increased rate of rearrangements in resistance gene-like loci. Here, we report that tobacco plants infected with TMV exhibited an increase in HRF in two consecutive generations. Analysis of global genome methylation showed the hypermethylated genome in both generations of plants, whereas analysis of methylation via 5-methyl cytosine antibodies demonstrated both hypomethylation and hypermethylation. Analysis of the response of the progeny of infected plants to TMV, Pseudomonas syringae, or Phytophthora nicotianae revealed a significant delay in symptom development. Infection of these plants with TMV or P. syringae showed higher levels of induction of PATHOGENESIS-RELATED GENE1 gene expression and higher levels of callose deposition. Our experiments suggest that viral infection triggers specific changes in progeny that promote higher levels of HRF at the transgene and higher resistance to stress as compared with the progeny of unstressed plants. However, data reported in these studies do not establish evidence of a link between recombination frequency and stress resistance. PMID:20498336

  11. International Faculty in American Universities: Experiences of Academic Life, Productivity, and Career Mobility

    ERIC Educational Resources Information Center

    Kim, Dongbin; Twombly, Susan; Wolf-Wendel, Lisa

    2012-01-01

    In the past 20 years, the number of international faculty members at American universities has continued to increase rapidly. This growth is evident in data showing that the proportional representation of foreign-born faculty easily surpasses that of domestic underrepresented racial/ethnic groups. The increasing presence of international faculty…

  12. Increased Exposure to Rigid Routines Can Lead to Increased Challenging Behavior Following Changes to Those Routines

    ERIC Educational Resources Information Center

    Bull, Leah E.; Oliver, Chris; Callaghan, Eleanor; Woodcock, Kate A.

    2015-01-01

    Several neurodevelopmental disorders are associated with preference for routine and challenging behavior following changes to routines. We examine individuals with Prader-Willi syndrome, who show elevated levels of this behavior, to better understand how previous experience of a routine can affect challenging behavior elicited by disruption to…

  13. Effects of Solid Solution Strengthening Elements Mo, Re, Ru, and W on Transition Temperatures in Nickel-Based Superalloys with High γ'-Volume Fraction: Comparison of Experiment and CALPHAD Calculations

    NASA Astrophysics Data System (ADS)

    Ritter, Nils C.; Sowa, Roman; Schauer, Jan C.; Gruber, Daniel; Goehler, Thomas; Rettig, Ralf; Povoden-Karadeniz, Erwin; Koerner, Carolin; Singer, Robert F.

    2018-06-01

    We prepared 41 different superalloy compositions by an arc melting, casting, and heat treatment process. Alloy solid solution strengthening elements were added in graded amounts, and we measured the solidus, liquidus, and γ'-solvus temperatures of the samples by DSC. The γ'-phase fraction increased as the W, Mo, and Re contents were increased, and W showed the most pronounced effect. Ru decreased the γ'-phase fraction. Melting temperatures (i.e., solidus and liquidus) were increased by addition of Re, W, and Ru (the effect increased in that order). Addition of Mo decreased the melting temperature. W was effective as a strengthening element because it acted as a solid solution strengthener and increased the fraction of fine γ'-precipitates, thus improving precipitation strengthening. Experimentally determined values were compared with calculated values based on the CALPHAD software tools Thermo-Calc (databases: TTNI8 and TCNI6) and MatCalc (database ME-NI). The ME-NI database, which was specially adapted to the present investigation, showed good agreement. TTNI8 also showed good results. The TCNI6 database is suitable for computational design of complex nickel-based superalloys. However, a large deviation remained between the experiment results and calculations based on this database. It also erroneously predicted γ'-phase separations and failed to describe the Ru-effect on transition temperatures.

  14. Open Hearts Build Lives: Positive Emotions, Induced Through Loving-Kindness Meditation, Build Consequential Personal Resources

    PubMed Central

    Fredrickson, Barbara L.; Cohn, Michael A.; Coffey, Kimberly A.; Pek, Jolynn; Finkel, Sandra M.

    2011-01-01

    B. L. Fredrickson’s (1998, 2001) broaden-and-build theory of positive emotions asserts that people’s daily experiences of positive emotions compound over time to build a variety of consequential personal resources. The authors tested this build hypothesis in a field experiment with working adults (n = 139), half of whom were randomly-assigned to begin a practice of loving-kindness meditation. Results showed that this meditation practice produced increases over time in daily experiences of positive emotions, which, in turn, produced increases in a wide range of personal resources (e.g., increased mindfulness, purpose in life, social support, decreased illness symptoms). In turn, these increments in personal resources predicted increased life satisfaction and reduced depressive symptoms. Discussion centers on how positive emotions are the mechanism of change for the type of mind-training practice studied here and how loving-kindness meditation is an intervention strategy that produces positive emotions in a way that outpaces the hedonic treadmill effect. PMID:18954193

  15. A comparison of cirrus clouds determined by ISCCP and SAGE-II and their relation to convection in the tropics

    NASA Technical Reports Server (NTRS)

    Christopher, Sundar A.; Vonder Haar, Thomas H.

    1992-01-01

    Results of tropical thin cirrus cloud retrievals using International Satellite Cloud Climatology Project (ISCCP) and Stratospheric Aerosol and Gaseous Experiment (SAGE-II) data from January 1985 are presented. A preliminary analysis of the results shows that thin cirrus increases with increasing height in both data sets, and SAGE-II exhibits a high frequency of occurrence. The thin cirrus extinction coefficient shows maxima around the convective regions of South America and the western Pacific Ocean.

  16. Osmolytic Effect of Sucrose on Thermal Denaturation of Pea Seedling Copper Amine Oxidase.

    PubMed

    Amani, Mojtaba; Barzegar, Aboozar; Mazani, Mohammad

    2017-04-01

    Protein stability is a subject of interest by many researchers. One of the common methods to increase the protein stability is using the osmolytes. Many studies and theories analyzed and explained osmolytic effect by equilibrium thermodynamic while most proteins undergo an irreversible denaturation. In current study we investigated the effect of sucrose as an osmolyte on the thermal denaturation of pea seedlings amine oxidase by the enzyme activity, fluorescence spectroscopy, circular dichroism, and differential scanning calorimetry. All experiments are in agreement that pea seedlings amine oxidase denaturation is controlled kinetically and its kinetic stability is increased in presence of sucrose. Differential scanning calorimetry experiments at different scanning rates showed that pea seedlings amine oxidase unfolding obeys two-state irreversible model. Fitting the differential scanning calorimetry data to two-state irreversible model showed that unfolding enthalpy and T * , temperature at which rate constant equals unit per minute, are increased while activation energy is not affected by increase in sucrose concentration. We concluded that osmolytes decrease the molecular oscillation of irreversible proteins which leads to decline in unfolding rate constant.

  17. [The educational reach of discussion in small groups. The role of the professor's differential experience].

    PubMed

    García-Mangas, José Alberto; Viniegra-Velázquez, Leonardo

    2008-01-01

    The teachers' formation program at IMSS includes the methodological diplomate in teaching level I (DMDI) and level II (DMDII). This program is based in educational strategies that promote the participation (guide towards knowledge elaboration). The importance of discussion in small groups (subgroups) to increase learning has been showed as part of such strategies. To evaluate the influence in learning of the professors' experience in coordinating the subgroup discussion. Three groups of students were included (professors in teaching formation) that had consecutively studied the DMDI: DMDIa, DMDIb, and DMDIc. There was also included a group of DMDII whose students had participated in DMDI as coordinators of the subgroup discussion of DMDIb and DMDIc (DMDIa did not count with coordinators). Two instruments previously validated were used to evaluate the development of a position about education and scientific work (indicator of both: % of consequence). Evaluations were made at the beginning and end of each DMDI. Position in education: at the beginning DMDIa = 36; DMDIb = 30, DMDIc = 31, without differences among them (p 0.65). After the interventions the increases were: DMDIa from 36 to 75 (p < 0.01), DMDIb from 30 to 91 (p < 0.01), DMDIc from 31 to 90 (p < 0.01). When comparing the groups among themselves, differences were found between DMDIa and DMDIb, DMDIa and DMDIc, and no differences were found between DMDIb and DMDIc. Position about scientific work: at the beginning DMDIa = 20; DMDIb = 14; DMDIc = 15 (p. 0.35). After the interventions the increases were: DMDIa from 20 to 35 (p < 0.05); DMDIb from 14 to 53 (p < 0.02), DMDIc from 15 to 79 (p < 0.001). When comparing the groups among themselves, difference was found between DMDIb and DMDIc (p < 0.02) and from these two and DMDIa. The results support the hypothesis that the professor's experience in the coordination of subgroup discussion has a notorious influence in learning. The DMDIa group that did not have this support showed lower advances with both instruments. The DMDIb group that had coordinating professors with little experience had equivalent advances to DMDIc in position about education, and lower advances in the position about scientific work. The DMDIc group whose coordinating professors had a previous experience with the DMDIb group showed the greatest increases. Features of educational strategy promoting the participation are described as well as the importance of the experience of the professor in coordinating the discussion, to increase learning.

  18. Cancer patients' attitudes and experiences of online access to their electronic medical records: A qualitative study.

    PubMed

    Rexhepi, Hanife; Åhlfeldt, Rose-Mharie; Cajander, Åsa; Huvila, Isto

    2018-06-01

    Patients' access to their online medical records serves as one of the cornerstones in the efforts to increase patient engagement and improve healthcare outcomes. The aim of this article is to provide in-depth understanding of cancer patients' attitudes and experiences of online medical records, as well as an increased understanding of the complexities of developing and launching e-Health services. The study result confirms that online access can help patients prepare for doctor visits and to understand their medical issues. In contrast to the fears of many physicians, the study shows that online access to medical records did not generate substantial anxiety, concerns or increased phone calls to the hospital.

  19. Perceived duration decreases with increasing eccentricity.

    PubMed

    Kliegl, Katrin M; Huckauf, Anke

    2014-07-01

    Previous studies examining the influence of stimulus location on temporal perception yield inhomogeneous and contradicting results. Therefore, the aim of the present study is to soundly examine the effect of stimulus eccentricity. In a series of five experiments, subjects compared the duration of foveal disks to disks presented at different retinal eccentricities on the horizontal meridian. The results show that the perceived duration of a visual stimulus declines with increasing eccentricity. The effect was replicated with various stimulus orders (Experiments 1-3), as well as with cortically magnified stimuli (Experiments 4-5), ruling out that the effect was merely caused by different cortical representation sizes. The apparent decreasing duration of stimuli with increasing eccentricity is discussed with respect to current models of time perception, the possible influence of visual attention and respective underlying physiological characteristics of the visual system. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Dopaminergic stimulation enhances confidence and accuracy in seeing rapidly presented words.

    PubMed

    Lou, Hans C; Skewes, Joshua C; Thomsen, Kristine Rømer; Overgaard, Morten; Lau, Hakwan C; Mouridsen, Kim; Roepstorff, Andreas

    2011-02-23

    Liberal acceptance, overconfidence, and increased activity of the neurotransmitter dopamine have been proposed to account for abnormal sensory experiences, for instance, hallucinations in schizophrenia. In normal subjects, increased sensory experience in Yoga Nidra meditation is linked to striatal dopamine release. We therefore hypothesize that the neurotransmitter dopamine may function as a regulator of subjective confidence of visual perception in the normal brain. Although much is known about the effect of stimulation by neurotransmitters on cognitive functions, their effect on subjective confidence of perception has never been recorded experimentally before. In a controlled study of 24 normal, healthy female university students with the dopamine agonist pergolide given orally, we show that dopaminergic activation increases confidence in seeing rapidly presented words. It also improves performance in a forced-choice word recognition task. These results demonstrate neurotransmitter regulation of subjective conscious experience of perception and provide evidence for a crucial role of dopamine.

  1. Strengthened African summer monsoon in the mid-Piacenzian

    NASA Astrophysics Data System (ADS)

    Zhang, Ran; Zhang, Zhongshi; Jiang, Dabang; Yan, Qing; Zhou, Xin; Cheng, Zhigang

    2016-09-01

    Using model results from the first phase of the Pliocene Model Intercomparison Project (PlioMIP) and four experiments with CAM4, the intensified African summer monsoon (ASM) in the mid-Piacenzian and corresponding mechanisms are analyzed. The results from PlioMIP show that the ASM intensified and summer precipitation increased in North Africa during the mid-Piacenzian, which can be explained by the increased net energy in the atmospheric column above North Africa. Further experiments with CAM4 indicated that the combined changes in the mid-Piacenzian of atmospheric CO2 concentration and SST, as well as the vegetation change, could have substantially increased the net energy in the atmospheric column over North Africa and further intensified the ASM. The experiments also demonstrated that topography change had a weak effect. Overall, the combined changes of atmospheric CO2 concentration and SST were the most important factor that brought about the intensified ASM in the mid-Piacenzian.

  2. Mid-Atomic-Number Cylindrical Wire Array Precursor Plasma Studies on Zebra

    DOE PAGES

    Stafford, A; Safronova, A. S.; Kantsyrev, V. L.; ...

    2014-12-30

    The precursor plasmas from low wire number cylindrical wire arrays (CWAs) were previously shown to radiate at temperatures >300 eV for Ni-60 (94% Cu and 6% Ni) wires in experiments on the 1-MA Zebra generator. Continued research into precursor plasmas has studied additional midatomic-number materials including Cu and Alumel (95% Ni, 2% Al, 2% Mn, and 1% Si) to determine if the >300 eV temperatures are common for midatomic-number materials. Additionally, current scaling effects were observed by performing CWA precursor experiments at an increased current of 1.5 MA using a load current multiplier. Our results show an increase in amore » linear radiation yield of ~50% (16 versus 10 kJ/cm) for the experiments at increased current. However, plasma conditions inferred through the modeling of X-ray time-gated spectra are very similar for the precursor plasma in both current conditions.« less

  3. [Effects of long-term fertilization on organic nitrogen fractions in aquic brown soil].

    PubMed

    Ren, Jin Feng; Zhou, Hua; Ma, Qiang; Xu, Yong Gang; Jiang, Chun Ming; Pan, Fei Fei; Yu, Wan Tai

    2017-05-18

    The purpose of present research was to investigate how different fertilization regimes altered soil organic nitrogen fractions and their inter-annual dynamics based on a series of long-term experiment (initiated at 1990), including: CK (non-fertilization); M (recycled pig manure); NPK (chemical fertilizer NPK); NPK + M (recycled pig manure with chemical fertilizer NPK). The results showed that soil organic nitrogen components under the different fertilization treatments presented contrastive patterns from the establishment the experiments to 2015. Generally, acid hydrolysable organic nitrogen content increased year by year. The amino acid nitrogen content under CK and NPK treatments consistently declined, although amino acid nitrogen for M and NPK+M treatments showed a increasing trend. These phenomena were probably ascribed to the utilization of soil amino acids by microbes. From 1990 to 2015, NPK treatment substantially elevated the content of acid-released ammonium nitrogen by 31.1% compared with CK (mean value across the experiment), and for the treatments using organic manure (M and NPK+M), the contents of all fractions of soil organic nitrogen increased. Notably, the increase magnitudes for NPK+M were more dramatic than those of M. These results demonstrated that combined use of organic and inorganic fertilizers could more effectively elevate soil organic nitrogen, subsequently helping to improve the capacity of soil nitrogen supply and enhance the soil fertility.

  4. Achieving ethanol-type fermentation for hydrogen production in a granular sludge system by aeration.

    PubMed

    Zhang, Song; Liu, Min; Chen, Ying; Pan, Yu-Ting

    2017-01-01

    To investigate the effects of aeration on hydrogen-producing granular system, experiments were performed in two laboratory-scale anaerobic internal circulation hydrogen production (AICHP) reactors. The preliminary experiment of Reactor 1 showed that direct aeration was beneficial to enhancing hydrogen production. After the direct aeration was implied in Reactor 2, hydrogen production rate (HPR) and hydrogen content were increased by 100% and 60%, respectively. In addition, mixed-acid fermentation was transformed into typical ethanol-type fermentation (ETF). Illumina MiSeq sequencing shows that the direct aeration did not change the species of hydrogen-producing bacteria but altered their abundance. Hydrogen-producing bacteria and ethanol-type fermentative bacteria were increased by 24.5% and 146.3%, respectively. Ethanoligenens sp. sharply increased by 162.2% and turned into predominant bacteria in the system. These findings indicated that appropriate direct aeration might be a novel and promising way to obtain ETF and enhance hydrogen production in practical use. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Biosorption of metal ions from aqueous solutions

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

    Chen, Jiaping; Yiacoumi, Sotira

    1997-01-01

    Copper biosorption from aqueous solutions by calcium alginate is reported in this paper. The experimental section includes potentiometric titrations of biosorbents, batch equilibrium and kinetic studies of copper biosorption, as well as fixed-bed biosorption experiments. The potentiometric titration results show that the surface charge increases with decreasing pH. The biosorption of copper strongly depends on solution pH; the metal ion binding increases from 0 to 90 percent in pH ranging from 1.5 to 5.0. In addition, a decrease in ionic strength results in an increase of copper ion removal. Kinetic studies indicate that mass transfer plays an important role inmore » the biosorption rate. Furthermore, a fixed-bed biosorption experiment shows that calcium alginate has a significant capacity for copper ion removal. The two-pK Basic Stem model successfully represents the surface charge and equilibrium biosorption experimental data. The calculation results demonstrate that the copper removal may result from the binding of free copper and its hydroxide with surface functional groups of the biosorbents.« less

  6. Multiple P2Y receptor subtypes in the apical membranes of polarized epithelial cells

    PubMed Central

    McAlroy, H L; Ahmed, S; Day, S M; Baines, D L; Wong, H Y; Yip, C Y; Ko, W H; Wilson, S M; Collett, A

    2000-01-01

    Apical ATP, ATP, UTP and UDP evoked transient increases in short circuit current (ISC, a direct measure of transepithelial ion transport) in confluent Caco-2 cells grown on permeable supports. These responses were mediated by a population of at least three pharmacologically distinct receptors. Experiments using cells grown on glass coverslips showed that ATP and UTP consistently increased intracellular free calcium ([Ca2+]i) whilst sensitivity to UDP was variable. Cross desensitization experiments suggested that the responses to UTP and ATP were mediated by a common receptor population. Messenger RNA transcripts corresponding to the P2Y2, P2Y4 and P2Y6 receptors genes were detected in cells grown on Transwell membranes by the reverse transcriptase–polymerase chain reaction. Identical results were obtained for cells grown on glass. Experiments in which ISC and [Ca2+]i were monitored simultaneously in cells on Transwell membranes, confirmed that apical ATP and UTP increased both parameters and showed that the UDP-evoked increase in ISC was accompanied by a [Ca2+]i-signal. Ionomycin consistently increased [Ca2+]i in such polarized cells but caused no discernible change in ISC. However, subsequent application of apical ATP or UTP evoked a small rise in ISC but no rise in [Ca2+]i. UDP evoked no such response. As well as evoking increases in [Ca2+]i, the ATP/UTP-sensitive receptors present in Caco-2 cells thus allow direct control over ion channels in the apical membrane. The UDP-sensitive receptors, however, appear to simply evoke a rise in [Ca2+]i. PMID:11139443

  7. Inhibition of angiotensin-converting enzyme increases oestradiol production in ewes submitted to oestrous synchronization protocol.

    PubMed

    Costa, A s; Junior, A S; Viana, G E N; Muratori, M C S; Reis, A M; Costa, A P R

    2014-10-01

    This study aimed at evaluating the effects of angiotensin-converting enzyme inhibitor (enalapril) and angiotensin II antagonist (valsartan) on the oestradiol and progesterone production in ewes submitted to oestrous synchronization protocol. The animals were weighed and randomly divided into three groups (n = 7). A pre-experiment conducted to verify the effectiveness and toxicity of enalapril (0.5 mg/kg LW) and valsartan (2.2 mg/kg LW) showed that, in the doses used, these drugs were effective in reducing blood pressure without producing toxic effects. In the experiment, all animals were subjected to oestrous synchronization protocol during 12 days. On D10, D11 and D12, animals received saline, enalapril or valsartan (same doses of the pre-experiment), according to the group randomly divided. The hormonal analysis showed an increase in oestradiol on the last day of the protocol (D12) in animals that received enalapril (p < 0.05), but not in other groups, without changing the concentration of progesterone in any of the treatments. It is concluded that valsartan and enalapril are safe and effective subcutaneously for use in sheep and that the angiotensin-converting enzyme (ACE) inhibition with enalapril leads to an increase in oestradiol production near ovulation without changing the concentration of progesterone. This shows that ACE inhibition may be a useful tool in reproductive biotechnologies involving induction and synchronization of oestrus and ovulation in sheep. © 2014 Blackwell Verlag GmbH.

  8. Pore fluid pressure and the seismic cycle

    NASA Astrophysics Data System (ADS)

    French, M. E.; Zhu, W.; Hirth, G.; Belzer, B.

    2017-12-01

    In the brittle crust, the critical shear stress required for fault slip decreases with increasing pore fluid pressures according to the effective stress criterion. As a result, higher pore fluid pressures are thought to promote fault slip and seismogenesis, consistent with observations that increasing fluid pressure as a result of wastewater injection is correlated with increased seismicity. On the other hand, elevated pore fluid pressure is also proposed to promote slow stable failure rather than seismicity along some fault zones, including during slow slip in subduction zones. Here we review recent experimental evidence for the roles that pore fluid pressure and the effective stress play in controlling fault slip behavior. Using two sets of experiments on serpentine fault gouge, we show that increasing fluid pressure does decrease the shear stress for reactivation under brittle conditions. However, under semi-brittle conditions as expected near the base of the seismogenic zone, high pore fluid pressures are much less effective at reducing the shear stress of reactivation even though deformation is localized and frictional. We use an additional study on serpentinite to show that cohesive fault rocks, potentially the product of healing and cementation, experience an increase in fracture energy during faulting as fluid pressures approach lithostatic, which can lead to more stable failure. Structural observations show that the increased fracture energy is associated with a greater intensity of transgranular fracturing and delocalization of deformation. Experiments on several lithologies indicate that the stabilizing effect of fluid pressure occurs independent of rock composition and hydraulic properties. Thus, high pore fluid pressures have the potential to either enhance seismicity or promote stable faulting depending on pressure, temperature, and fluid pressure conditions. Together, the results of these studies indicate that pore fluid pressure promotes seismogenesis in the brittle shallow crust where fluid pressures are elevated but sub-lithostatic and promote slow, stable failure near seismic to aseismic transitions and under near-lithostatic fluid pressures.

  9. Large Diameter, Radiative Extinction Experiments with Decane Droplets in Microgravity

    NASA Technical Reports Server (NTRS)

    Easton, John; Tien, James; Dietrich, Daniel

    1999-01-01

    The extinction of a diffusion flame is of fundamental interest in combustion science. Linan, Law, and Chung and Law analytically and experimentally determined an extinction boundary in terms of droplet diameter and pressure for a single droplet due to Damkohler, or blowoff, extinction. More recently, other researchers demonstrated extinction due to finite rate kinetics in reduced gravity for free droplets of heptane. Chao modeled the effect of radiative heat loss on a quasi-steady spherically symmetric single droplet burning in the absence of buoyancy. They determined that for increasing droplet diameter, a second limit can be reached such that combustion is no longer possible. This second, larger droplet diameter limit arises due to radiative heat loss, which increases with increasing droplet and flame diameter. This increase in radiative heat loss arises due to an increase in the surface area of the flame. Recently, Marchese modeled fuel droplets with detailed chemistry and radiative effects, and compared the results to other work. The modeling also showed the importance of radiative loss and radiative extinction Experiments examined the behavior of a large droplet of decane burning in reduced gravity onboard the NASA Lewis DC-9 aircraft, but did not show a radiative extinction boundary due to g-jitter (Variations in gravitational level and direction) effects. Dietrich conducted experiments in the reduced gravity environment of the Space Shuttle. This work showed that the extinction diameter of methanol droplets increased when the initial diameter of the droplets was large (in this case, approximately 5 mm). Theoretical results agreed with these experimental results only when the theory included radiative effects . Radiative extinction was experimentally verified by Nayagam in a later Shuttle mission. The following work focuses on the combustion and extinction of a single fuel droplet. The goal is to experimentally determine a large droplet diameter limit that arises due to radiative heat loss from the flame to the surroundings.

  10. Soil invertebrate fauna affect N2 O emissions from soil.

    PubMed

    Kuiper, Imke; de Deyn, Gerlinde B; Thakur, Madhav P; van Groenigen, Jan Willem

    2013-09-01

    Nitrous oxide (N2 O) emissions from soils contribute significantly to global warming. Mitigation of N2 O emissions is severely hampered by a lack of understanding of its main controls. Fluxes can only partly be predicted from soil abiotic factors and microbial analyses - a possible role for soil fauna has until now largely been overlooked. We studied the effect of six groups of soil invertebrate fauna and tested the hypothesis that all of them increase N2 O emissions, although to different extents. We conducted three microcosm experiments with sandy soil and hay residue. Faunal groups included in our experiments were as follows: fungal-feeding nematodes, mites, springtails, potworms, earthworms and isopods. In experiment I, involving all six faunal groups, N2 O emissions declined with earthworms and potworms from 78.4 (control) to 37.0 (earthworms) or 53.5 (potworms) mg N2 O-N m(-2) . In experiment II, with a higher soil-to-hay ratio and mites, springtails and potworms as faunal treatments, N2 O emissions increased with potworms from 51.9 (control) to 123.5 mg N2 O-N m(-2) . Experiment III studied the effect of potworm density; we found that higher densities of potworms accelerated the peak of the N2 O emissions by 5 days (P < 0.001), but the cumulative N2 O emissions remained unaffected. We propose that increased soil aeration by the soil fauna reduced N2 O emissions in experiment I, whereas in experiment II N2 O emissions were driven by increased nitrogen and carbon availability. In experiment III, higher densities of potworms accelerated nitrogen and carbon availability and N2 O emissions, but did not increase them. Overall, our data show that soil fauna can suppress, increase, delay or accelerate N2 O emissions from soil and should therefore be an integral part of future N2 O studies. © 2013 John Wiley & Sons Ltd.

  11. How social exclusion modulates social information processing: A behavioural dissociation between facial expressions and gaze direction

    PubMed Central

    Gallucci, Marcello; Ricciardelli, Paola

    2018-01-01

    Social exclusion is a painful experience that is felt as a threat to the human need to belong and can lead to increased aggressive and anti-social behaviours, and results in emotional and cognitive numbness. Excluded individuals also seem to show an automatic tuning to positivity: they tend to increase their selective attention towards social acceptance signals. Despite these effects known in the literature, the consequences of social exclusion on social information processing still need to be explored in depth. The aim of this study was to investigate the effects of social exclusion on processing two features that are strictly bound in the appraisal of the meaning of facial expressions: gaze direction and emotional expression. In two experiments (N = 60, N = 45), participants were asked to identify gaze direction or emotional expressions from facial stimuli, in which both these features were manipulated. They performed these tasks in a four-block crossed design after being socially included or excluded using the Cyberball game. Participants’ empathy and self-reported emotions were recorded using the Empathy Quotient (EQ) and PANAS questionnaires. The Need Threat Scale and three additional questions were also used as manipulation checks in the second experiment. In both experiments, excluded participants showed to be less accurate than included participants in gaze direction discrimination. Modulatory effects of direct gaze (Experiment 1) and sad expression (Experiment 2) on the effects of social exclusion were found on response times (RTs) in the emotion recognition task. Specific differences in the reaction to social exclusion between males and females were also found in Experiment 2: excluded male participants tended to be less accurate and faster than included male participants, while excluded females showed a more accurate and slower performance than included female participants. No influence of social exclusion on PANAS or EQ scores was found. Results are discussed in the context of the importance of identifying gaze direction in appraisal theories. PMID:29617410

  12. Effect of Stepwise Pressure Change on Porosity Evolution during Directional Solidification in Small Cylindrical Channels

    NASA Technical Reports Server (NTRS)

    Grugel, R.N.; Lee, C.P.; Cox, M.C.; Blandford, B.T.; Anilkumar, A.V.

    2008-01-01

    Controlled directional solidification experiments were performed in capillary channels, using nitrogen-saturated succinonitrile, to examine the effect of an in-situ stepwise processing pressure increase on an isolated pore evolution. Two experiments were performed using different processing pressure input profiles. The results indicate that a processing pressure increase has a transient effect on pore growth geometry characterized by an initial phase of decreasing pore diameter, followed by a recovery phase of increasing pore diameter. The experimental results also show that processing pressure can be used as a control parameter to either increase or terminate porosity formation. A theoretical model is introduced which indicates that the pore formation process is limited by the diffusion of solute-gas through the melt, and that the observed response toa pressure increase is attributed to the re-equilibration of solute concentration in the melt associated with the increased melt pressure.

  13. Perirhinal Cortex Lesions in Rats: Novelty Detection and Sensitivity to Interference

    PubMed Central

    2015-01-01

    Rats with perirhinal cortex lesions received multiple object recognition trials within a continuous session to examine whether they show false memories. Experiment 1 focused on exploration patterns during the first object recognition test postsurgery, in which each trial contained 1 novel and 1 familiar object. The perirhinal cortex lesions reduced time spent exploring novel objects, but did not affect overall time spent exploring the test objects (novel plus familiar). Replications with subsequent cohorts of rats (Experiments 2, 3, 4.1) repeated this pattern of results. When all recognition memory data were combined (Experiments 1–4), giving totals of 44 perirhinal lesion rats and 40 surgical sham controls, the perirhinal cortex lesions caused a marginal reduction in total exploration time. That decrease in time with novel objects was often compensated by increased exploration of familiar objects. Experiment 4 also assessed the impact of proactive interference on recognition memory. Evidence emerged that prior object experience could additionally impair recognition performance in rats with perirhinal cortex lesions. Experiment 5 examined exploration levels when rats were just given pairs of novel objects to explore. Despite their perirhinal cortex lesions, exploration levels were comparable with those of control rats. While the results of Experiment 4 support the notion that perirhinal lesions can increase sensitivity to proactive interference, the overall findings question whether rats lacking a perirhinal cortex typically behave as if novel objects are familiar, that is, show false recognition. Rather, the rats retain a signal of novelty but struggle to discriminate the identity of that signal. PMID:26030425

  14. When conflicts are good: nonconscious goal conflicts reduce confirmatory thinking.

    PubMed

    Kleiman, Tali; Hassin, Ran R

    2013-09-01

    In this article, we argue that nonconscious goal conflicts are accompanied by a mindset that has wide-ranging implications for reasoning and thinking in content areas that are not part of the conflict itself. Specifically, we propose that nonconscious goal conflicts induce a mode of processing information that increases the likelihood of approaching an issue from opposing perspectives. This hypothesis is examined by investigating the effects of nonconscious goal conflicts on confirmatory thinking, that is, a way of thinking that narrowly focuses on confirmation rather than on broader examination of information. In 5 experiments, we show that nonconscious goal conflicts significantly reduce confirmatory hypothesis testing (Experiments 1 through 3) and anchoring (Experiments 4 and 5). We further show that these effects result from a goal conflict by rejecting explanations based on priming of semantic opposites, and priming of multiple goals that do not conflict (Experiments 2 and 3), and by examining decision times as a conflict process variable (Experiment 5). Using various probes, we show that these changes in confirmatory judgments are not accompanied by changes in conflict phenomenology. Together, these results suggest that nonconscious goal conflicts attenuate the robust confirmatory thinking strategy that characterizes human thinking in numerous domains.

  15. Perceived beauty of random texture patterns: A preference for complexity.

    PubMed

    Friedenberg, Jay; Liby, Bruce

    2016-07-01

    We report two experiments on the perceived aesthetic quality of random density texture patterns. In each experiment a square grid was filled with a progressively larger number of elements. Grid size in Experiment 1 was 10×10 with elements added to create a variety of textures ranging from 10%-100% fill levels. Participants rated the beauty of the patterns. Average judgments across all observers showed an inverted U-shaped function that peaked near middle densities. In Experiment 2 grid size was increased to 15×15 to see if observers preferred patterns with a fixed density or a fixed number of elements. The results of the second experiment were nearly identical to that of the first showing a preference for density over fixed element number. Ratings in both studies correlated positively with a GIF compression metric of complexity and with edge length. Within the range of stimuli used, observers judge more complex patterns to be more beautiful. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. A recursive Bayesian updating model of haptic stiffness perception.

    PubMed

    Wu, Bing; Klatzky, Roberta L

    2018-06-01

    Stiffness of many materials follows Hooke's Law, but the mechanism underlying the haptic perception of stiffness is not as simple as it seems in the physical definition. The present experiments support a model by which stiffness perception is adaptively updated during dynamic interaction. Participants actively explored virtual springs and estimated their stiffness relative to a reference. The stimuli were simulations of linear springs or nonlinear springs created by modulating a linear counterpart with low-amplitude, half-cycle (Experiment 1) or full-cycle (Experiment 2) sinusoidal force. Experiment 1 showed that subjective stiffness increased (decreased) as a linear spring was positively (negatively) modulated by a half-sinewave force. In Experiment 2, an opposite pattern was observed for full-sinewave modulations. Modeling showed that the results were best described by an adaptive process that sequentially and recursively updated an estimate of stiffness using the force and displacement information sampled over trajectory and time. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  17. False Memories for Suggestions: The Impact of Conceptual Elaboration

    PubMed Central

    Zaragoza, Maria S.; Mitchell, Karen J.; Payment, Kristie; Drivdahl, Sarah

    2010-01-01

    Relatively little attention has been paid to the potential role that reflecting on the meaning and implications of suggested events (i.e., conceptual elaboration) might play in promoting the creation of false memories. Two experiments assessed whether encouraging repeated conceptual elaboration, would, like perceptual elaboration, increase false memory for suggested events. Results showed that conceptual elaboration of suggested events more often resulted in high confidence false memories (Experiment 1) and false memories that were accompanied by the phenomenal experience of remembering them (Experiment 2) than did surface-level processing. Moreover, conceptual elaboration consistently led to higher rates of false memory than did perceptual elaboration. The false memory effects that resulted from conceptual elaboration were highly dependent on the organization of the postevent interview questions, such that conceptual elaboration only increased false memory beyond surface level processing when participants evaluated both true and suggested information in relation to the same theme or dimension. PMID:21103451

  18. Manipulating affective state influences conditioned appetitive responses.

    PubMed

    Arnaudova, Inna; Krypotos, Angelos-Miltiadis; Effting, Marieke; Kindt, Merel; Beckers, Tom

    2017-10-06

    Affective states influence how individuals process information and behave. Some theories predict emotional congruency effects (e.g. preferential processing of negative information in negative affective states). Emotional congruency should theoretically obstruct the learning of reward associations (appetitive learning) and their ability to guide behaviour under negative mood. Two studies tested the effects of the induction of a negative affective state on appetitive Pavlovian learning, in which neutral stimuli were associated with chocolate (Experiment 1) or alcohol (Experiment 2) rewards. In both experiments, participants showed enhanced approach tendencies towards predictors of reward after a negative relative to a positive performance feedback manipulation. This increase was related to a reduction in positive affect in Experiment 1 only. No effects of the manipulation on conditioned reward expectancies, craving, or consumption were observed. Overall, our findings support the idea of counter-regulation, rather than emotional congruency effects. Negative affective states might therefore serve as a vulnerability factor for addiction, through increasing conditioned approach tendencies.

  19. Ultrafast modulation of the plasma frequency of vertically aligned indium tin oxide rods.

    PubMed

    Tice, Daniel B; Li, Shi-Qiang; Tagliazucchi, Mario; Buchholz, D Bruce; Weiss, Emily A; Chang, Robert P H

    2014-03-12

    Light-matter interaction at the nanoscale is of particular interest for future photonic integrated circuits and devices with applications ranging from communication to sensing and imaging. In this Letter a combination of transient absorption (TA) and the use of third harmonic generation as a probe (THG-probe) has been adopted to investigate the response of the localized surface plasmon resonances (LSPRs) of vertically aligned indium tin oxide rods (ITORs) upon ultraviolet light (UV) excitation. TA experiments, which are sensitive to the extinction of the LSPR, show a fluence-dependent increase in the frequency and intensity of the LSPR. The THG-probe experiments show a fluence-dependent decrease of the LSPR-enhanced local electric field intensity within the rod, consistent with a shift of the LSPR to higher frequency. The kinetics from both TA and THG-probe experiments are found to be independent of the fluence of the pump. These results indicate that UV excitation modulates the plasma frequency of ITO on the ultrafast time scale by the injection of electrons into, and their subsequent decay from, the conduction band of the rods. Increases to the electron concentration in the conduction band of ∼13% were achieved in these experiments. Computer simulation and modeling have been used throughout the investigation to guide the design of the experiments and to map the electric field distribution around the rods for interpreting far-field measurement results.

  20. The communication of "pure" group-based anger reduces tendencies toward intergroup conflict because it increases out-group empathy.

    PubMed

    de Vos, Bart; van Zomeren, Martijn; Gordijn, Ernestine H; Postmes, Tom

    2013-08-01

    The communication of group-based anger in intergroup conflict is often associated with destructive conflict behavior. However, we show that communicating group-based anger toward the out-group can evoke empathy and thus reduce intergroup conflict. This is because it stresses the value of maintaining a positive long-term intergroup relationship, thereby increasing understanding for the situation (in contrast to the communication of the closely related emotion of contempt). Three experiments demonstrate that the communication of group-based anger indeed reduces destructive conflict intentions compared with (a) a control condition (Experiments 1-2), (b) the communication of group-based contempt (Experiment 2), and (c) the communication of a combination of group-based anger and contempt (Experiments 2-3). Moreover, results from all three experiments reveal that empathy mediated the positive effect of communicating "pure" group-based anger. We discuss the implications of these findings for the theory and practice of communicating emotions in intergroup conflicts.

  1. Polycyclic aromatic hydrocarbons alter the structure of oceanic and oligotrophic microbial food webs.

    PubMed

    Cerezo, Maria Isabel; Agusti, Susana

    2015-12-30

    One way organic pollutants reach remote oceanic regions is by atmospheric transport. During the Malaspina-2010 expedition, across the Atlantic, Indian, and Pacific Oceans, we analyzed the polycyclic aromatic hydrocarbon (PAH) effects on oceanic microbial food webs. We performed perturbation experiments adding PAHs to classic dilution experiments. The phytoplankton growth rates were reduced by more than 5 times, being Prochlorococcus spp. the most affected. 62% of the experiments showed a reduction in the grazing rates due to the presence of PAHs. For the remaining experiments, grazing usually increased likely due to cascading effects. We identified changes in the slope of the relation between the growth rate and the dilution fraction induced by the pollutants, moving from no grazing to V-shape, or to negative slope, indicative of grazing increase by cascade effects and alterations of the grazers' activity structure. Our perturbation experiments indicate that PAHs could influence the structure oceanic food-webs structure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Mobilization of natural colloids from an iron oxide-coated sand aquifer--Effect of pH and ionic strength

    USGS Publications Warehouse

    Bunn, Rebecca A.; Magelky, Robin D.; Ryan, Joseph N.; Elimelech, Menachem

    2002-01-01

    Field and laboratory column experiments were performed to assess the effect of elevated pH and reduced ionic strength on the mobilization of natural colloids in a ferric oxyhydroxide-coated aquifer sediment. The field experiments were conducted as natural gradient injections of groundwater amended by sodium hydroxide additions. The laboratory experiments were conducted in columns of undisturbed, oriented sediments and disturbed, disoriented sediments. In the field, the breakthrough of released colloids coincided with the pH pulse breakthrough and lagged the bromide tracer breakthrough. The breakthrough behavior suggested that the progress of the elevated pH front controlled the transport of the mobilized colloids. In the laboratory, about twice as much colloid release occurred in the disturbed sediments as in the undisturbed sediments. The field and laboratory experiments both showed that the total mass of colloid release increased with increasing pH until the concurrent increase in ionic strength limited release. A decrease in ionic strength did not mobilize significant amounts of colloids in the field. The amount of colloids released normalized to the mass of the sediments was similar for the field and the undisturbed laboratory experiments.

  3. Effect of vermicompost on growth, yield and nutrition status of tomato (Lycopersicum esculentum).

    PubMed

    Azarmi, Rasool; Ziveh, Parviz Sharifi; Satari, Mohammad Reza

    2008-07-15

    An experiment was conducted to determine the effects of vermicompost on growth, yield and fruit quality of tomato (Lycopersicum esculentum var. Super Beta) in a field condition. The experiment was a randomized complete block design with four replications. The different rates of vermicompost (0, 5, 10 and 15 t ha(-1)) was incorporated into the top 15 cm of soil. During experiment period, fruits were harvested twice in a week and total yield were recorded for two months. At the end of experiment, growth characteristics such as leaf number, leaf area and shoot dry weights were determined. The results revealed that addition of vermicompost at rate of 15 t ha(-1) significantly (at p < 0.05) increased growth and yield compared to control. Vermicompost with rate of 15 t ha(-1) increased EC of fruit juice and percentage of fruit dry matter up to 30 and 24%, respectively. The content of K, P, Fe and Zn in the plant tissue increased 55, 73, 32 and 36% compared to untreated plots respectively. The result of our experiment showed addition of vermicompost had significant (p < 0.05) positive effects on growth, yield and elemental content of plant as compared to control.

  4. Guided-inquiry laboratory experiments to improve students' analytical thinking skills

    NASA Astrophysics Data System (ADS)

    Wahyuni, Tutik S.; Analita, Rizki N.

    2017-12-01

    This study aims to improve the experiment implementation quality and analytical thinking skills of undergraduate students through guided-inquiry laboratory experiments. This study was a classroom action research conducted in three cycles. The study has been carried out with 38 undergraduate students of the second semester of Biology Education Department of State Islamic Institute (SII) of Tulungagung, as a part of Chemistry for Biology course. The research instruments were lesson plans, learning observation sheets and undergraduate students' experimental procedure. Research data were analyzed using quantitative-descriptive method. The increasing of analytical thinking skills could be measured using gain score normalized and statistical paired t-test. The results showed that guided-inquiry laboratory experiments model was able to improve both the experiment implementation quality and the analytical thinking skills. N-gain score of the analytical thinking skills was increased, in spite of just 0.03 with low increase category, indicated by experimental reports. Some of undergraduate students have had the difficulties in detecting the relation of one part to another and to an overall structure. The findings suggested that giving feedback the procedural knowledge and experimental reports were important. Revising the experimental procedure that completed by some scaffolding questions were also needed.

  5. Effects of ferric iron reduction and regeneration on nitrous oxide and methane emissions in a rice soil.

    PubMed

    Huang, Bin; Yu, Kewei; Gambrell, Robert P

    2009-01-01

    A laboratory soil slurry experiment and an outdoor pot experiment were conducted to study effects of ferric iron (Fe(III)) reduction and regeneration on nitrous oxide (N(2)O) and methane (CH(4)) emissions in a rice (Oryza sativa L.) soil. The anoxic slurry experiment showed that enhancing microbial Fe(III) reduction by ferrihydrite amendment (40 mol Fe g(-1)) transitionally stimulated N(2)O production and lowered CH(4) production by 16% during an initial 33-day incubation. Increased regeneration of Fe(III) through a 4-day aeration period in the Fe-amended slurry compared to the control slurry reduced CH(4) emission by 30% in the subsequent 15-day anaerobic incubation. The pot experiment showed that ferrihydrite amendment (63 micromol Fe g(-1)) stimulated N(2)O fluxes in the days following flooding. The Fe amendment suppression on CH(4) emission was obscured in the early season but became significant upon reflooding in the mid- and late-seasons. As a result, seasonal CH(4) emission in Fe-amended pots was 26% lower than the control with a single 2-day drainage and 69% lower with a double 2-day drainage. The reduction in CH(4) emission upon reflooding from the Fe-amended pots was mainly attributed to the increased Fe(III) regeneration during drainage showing a mechanism of Fe(III) regeneration in mitigating CH(4) emission by short-term drainage in flooded soils.

  6. Toluene effects on the motor activity of adolescent, young-adult, middle-age and senescent male Brown Norway rats.

    PubMed

    MacPhail, R C; Farmer, J D; Jarema, K A

    2012-01-01

    Life stage is an important risk factor for toxicity. Children and aging adults, for example, are more susceptible to certain chemicals than are young adults. In comparison to children, relatively little is known about susceptibility in older adults. Additionally, few studies have compared toxicant susceptibility across a broad range of life stages. Results are presented for behavioral evaluations of male Brown Norway rats obtained as adolescents (1 month), or young (4 months), middle-age (12 months) and senescent (24 months) adults. Motor activity was evaluated in photocell devices during 30-min sessions. Age-related baseline characteristics and sensitivity to toluene (0, 300, 650, or 1000mg/kg, p.o.) were determined. In Experiment 1, young-adult, middle-age and senescent rats were treated with corn-oil vehicle before five weekly test sessions. Baselines of horizontal and vertical activity decreased with age, but each age-group's averages remained stable across weeks of testing. Baseline activity of older rats was more variable than that of the young adults; older rats were also more variable individually from week to week. Toluene (1000mg/kg) increased horizontal activity proportionately more in senescent rats (ca. 300% of control) than in middle-age or young-adult rats (ca.145-175% of control). Experiment 2 established toluene dose-effect functions in individual adolescent, young-adult, middle-age and senescent rats; each rat received all treatments, counterbalanced across four weekly sessions. Toluene produced dose-related increases in horizontal activity that increased proportionately with age. Experiment 3 replicated the effects of toluene (1000mg/kg) in Experiment 1, showing that toluene-induced increases in horizontal activity were greatest in the oldest rats. Collectively, the results show that aging increased susceptibility to toluene and also increased variability in toluene response. Given the rapid growth of the aged population, further research is needed on aging-related susceptibility to environmental contaminants. Published by Elsevier B.V.

  7. Land Husbandry: Biochar application to reduce land degradation and erosion on cassava production

    NASA Astrophysics Data System (ADS)

    Yuniwati, E. D.

    2017-12-01

    This field experiment was carried out to examine the effect of increasing crop yield on land degradation and erosion in cassava-based cropping systems. The experiment was also aimed at showing that with proper crop management, the planting of cassava does not result in land degradation, and therefore, a sustainable production system can be obtained. The experiment was done in a farmer's fields in Batu, about 15 km south east of Malang, East Java, Indonesia. The soils are Alfisols with a surface slope of about 8%. There were 8 experimental treatments with two replications. The experiment results show that biochar applications reduce of soil erosion rate of the cassava field were not necessarily higher than those of maize in terms of crop yield and crop management. At low-to-medium yield, also observed the nutrient uptake of cassava was lower than that of maize. At high yield, only the K uptake of cassava was higher than that of maize, whereas the N and P uptake was more or less similar. Soil erosion on the cassava field was significantly higher than that on the maize field; however, this only occurred when there was no suitable crop management. Simple crop managements, such as ridging, biochar application, or manure application could significantly reduce soil erosion. The results also revealed that proper management could prevent land degradation and increase crop yield. In turn, the increase in crop yield could decrease soil erosion and plant nutrient depletion.

  8. Biological studies of swine exposed to 60-Hz electric fields. Volume 7. Neurology. Final report

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

    Not Available

    1985-12-01

    Neurophysiological responses in three generations of miniature swine chronically exposed to a 30-kV/m, 60-Hz electric field have been assessed in a series of screening experiments. Results are presented from experiments on peripheral nerve function in parental (F/sub 0/) female swine at 100 days of gestation, and from experiments on synaptic transmission in first- and second-generation (F/sub 1/ and F/sub 2/) progeny at 6 weeks of age, all following chronic exposure to a 60-Hz electric field. In the several measures of peripheral nerve function examined, only two showed consistent differences between exposed and sham-exposed animals: C-fiber (but not B-fiber) conduction velocitymore » was decreased in nerve preparations from exposed swine, and recovery, as measured by the increase in amplitude of the compound action potential, was consistently, although not statistically, less in B- and C-fibers from exposed animals when compared to values for the sham-exposed controls. Although changes (increases or decreases) in various parameters of synaptic transmission were observed between exposed and sham-exposed groups, the differences were not consistent across experiments or generations. Only one measure of synaptic function showed a consistent difference throughout the studies: the conduction velocities of B and C components of the postsynaptic compound action potential were increased following electric-field exposure (statistically significant only in B-fibers of the F/sub 2/ generations). 7 refs., 60 figs., 17 tabs.« less

  9. Fretting wear of iron, nickel, and titanium under varied environmental conditions

    NASA Technical Reports Server (NTRS)

    Bill, R. C.

    1979-01-01

    Fretting wear experiments were conducted on high-purity iron, nickel and titanium in air under conditions of varied humidity and temperature, and in nitrogen. For iron and titanium, maximum fretting occurred at 10 and 30 percent relative humidity respectively. Nickel showed a minimum in fretting wear at about 10% relative humidity. With increasing temperature, all three metals initially showed reduced fretting wear, with increasing wear observed as temperatures increased beyond 200-300 C. For titanium, dramatically reduced fretting wear was observed at temperatures above 500 C, relatable to a change in oxidation kinetics. All three metals showed much less fretting wear in N2 with the presence of moisture in N2 having a proportionally stronger effect than in air.

  10. Fretting wear of iron, nickel, and titanium under varied environmental conditions

    NASA Technical Reports Server (NTRS)

    Bill, R. C.

    1978-01-01

    Fretting wear experiments were conducted on high purity iron, nickel and titanium in air under conditions of varied humidity and temperature, and in nitrogen. For iron and titanium, maximum fretting occurred at 10 and 30 percent relative humidity respectively. Nickel showed a minimum in fretting wear at about 10 percent relative humidity. With increasing temperature, all three metals initially showed reduced fretting wear, with increasing wear observed as temperatures increased beyond 200-300 C. For titanium, dramatically reduced fretting wear was observed at temperatures above 500 C, relatable to a change in oxidation kinetics. All three metals showed much less fretting wear in N2 with the presence of moisture in N2 having a proportionally stronger effect than in air.

  11. A statewide evaluation of the effectiveness of media literacy training to prevent tobacco use among adolescents.

    PubMed

    Pinkleton, Bruce E; Weintraub Austin, Erica; Cohen, Marilyn; Miller, Autumn; Fitzgerald, Erin

    2007-01-01

    Researchers used a quasi-experiment (N = 723) conducted in the field and using both pretests and posttests to carry out a theory-based evaluation of the effectiveness of a media literacy curriculum implemented in Washington state. Results showed that reflective thinking concerning media message about tobacco increased for all media literacy participants, whether or not they had used tobacco previously. Changes in reflective thinking affected a range of decision-making indicators. Lesson participants who had not used tobacco demonstrated greater change at earlier stages of decision making in ways that suggested a greater understanding of the persuasive techniques used by tobacco manufacturers, on indicators such as perceived realism, desirability, and similarity. Lesson participants who had tried tobacco demonstrated greater change at later stages of decision making on indicators such as perceived peer norms for tobacco use, identification with tobacco-related portrayals, and expectancies for tobacco use. All participants also showed increases in their ability and motivations to resist smoking-related influences. Overall, the results suggest that media literacy has important and somewhat different effects on those who have and those who have not experimented with tobacco use. The results also show the importance of measuring cognitive and affective indicators of decision making that may change gradually as participants gain experience putting lessons learned into action.

  12. Control of information in working memory: Encoding and removal of distractors in the complex-span paradigm.

    PubMed

    Oberauer, Klaus; Lewandowsky, Stephan

    2016-11-01

    The article reports four experiments with complex-span tasks in which encoding of memory items alternates with processing of distractors. The experiments test two assumptions of a computational model of complex span, SOB-CS: (1) distractor processing impairs memory because distractors are encoded into working memory, thereby interfering with memoranda; and (2) free time following distractors is used to remove them from working memory by unbinding their representations from list context. Experiment 1 shows that distractors are erroneously chosen for recall more often than not-presented stimuli, demonstrating that distractors are encoded into memory. Distractor intrusions declined with longer free time, as predicted by distractor removal. Experiment 2 shows these effects even when distractors precede the memory list, ruling out an account based on selective rehearsal of memoranda during free time. Experiments 3 and 4 test the notion that distractors decay over time. Both experiments show that, contrary to the notion of distractor decay, the chance of a distractor intruding at test does not decline with increasing time since encoding of that distractor. Experiment 4 provides additional evidence against the prediction from distractor decay that distractor intrusions decline over an unfilled retention interval. Taken together, the results support SOB-CS and rule out alternative explanations. Data and simulation code are available on Open Science Framework: osf.io/3ewh7. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Breast implants and breast cancer: a review of incidence, detection, mortality, and survival.

    PubMed

    Deapen, Dennis

    2007-12-01

    Soon after breast implants were commercially introduced over 30 years ago, questions about potential carcinogenicity were raised. Animal experiments dating back to the mid-twentieth century demonstrated that foreign body implantation of many materials, including silicone, can induce sarcomas. Indeed, female breast cancer incidence rates in the United States have increased substantially over that period. Of the several published studies from various countries that have formally investigated the risk of breast cancer among augmentation mammaplasty patients, none show any evidence of increased risk. In fact, most find lower than expected risk, some with statistically significant reductions. Similarly, breast cancer mortality among these patients is generally found to be below that expected of other similar women. Delayed detection of breast cancer is a concern for these patients because implants can interfere with mammography. However, using indicators such as stage at diagnosis and tumor size, current research shows that augmentation patients do not experience delayed detection. Furthermore, several comparisons of post-breast cancer survival of augmented versus nonaugmented patients have found no significant differences. In summary, breast implants are not associated with an increased risk of breast cancer incidence or death, and these patients do not experience delayed detection or poorer post-breast cancer survival.

  14. The Effect of an Increased Convective Entrainment Rate on Indian Monsoon Biases in the Met Office Unified Model

    NASA Astrophysics Data System (ADS)

    Bush, Stephanie; Turner, Andrew; Woolnough, Steve; Martin, Gill

    2013-04-01

    Global circulation models (GCMs) are a key tool for understanding and predicting monsoon rainfall, now and under future climate change. However, many GCMs show significant, systematic biases in their simulation of monsoon rainfall and dynamics that spin up over very short time scales and persist in the climate mean state. We describe several of these biases as simulated in the Met Office Unified Model and show they are sensitive to changes in the convective parameterization's entrainment rate. To improve our understanding of the biases and inform efforts to improve convective parameterizations, we explore the reasons for this sensitivity. We show the results of experiments where we increase the entrainment rate in regions of especially large bias: the western equatorial Indian Ocean, western north Pacific and India itself. We use the results to determine whether improvements in biases are due to the local increase in entrainment or are the remote response of the entrainment increase elsewhere in the GCM. We find that feedbacks usually strengthen the local response, but the local response leads to a different mean state change in different regions. We also show results from experiments which demonstrate the spin-up of the local response, which we use to further understand the response in complex regions such as the Western North Pacific. Our work demonstrates that local application of parameterization changes is a powerful tool for understanding their global impact.

  15. Stabilization of molten salt materials using metal chlorides for solar thermal storage.

    PubMed

    Dunlop, T O; Jarvis, D J; Voice, W E; Sullivan, J H

    2018-05-29

    The effect of a variety of metal-chlorides additions on the melting behavior and thermal stability of commercially available salts was investigated. Ternary salts comprised of KNO 3, NaNO 2, and NaNO 3 were produced with additions of a variety of chlorides (KCl, LiCl, CaCl 2 , ZnCl 2 , NaCl and MgCl 2 ). Thermogravimetric analysis and weight loss experiments showed that the quaternary salt containing a 5 wt% addition of LiCl and KCl led to an increase in short term thermal stability compared to the ternary control salts. These additions allowed the salts to remain stable up to a temperature of 630 °C. Long term weight loss experiments showed an upper stability increase of 50 °C. A 5 wt% LiCl addition resulted in a weight loss of only 25% after 30 hours in comparison to a 61% loss for control ternary salts. Calorimetry showed that LiCl additions allow partial melting at 80 °C, in comparison to the 142 °C of ternary salts. This drop in melting point, combined with increased stability, provided a molten working range increase of almost 100 °C in total, in comparison to the control ternary salts. XRD analysis showed the oxidation effect of decomposing salts and the additional phase created with LiCl additions to allow melting point changes to occur.

  16. Increasing the Size of a Piece of Popcorn

    NASA Astrophysics Data System (ADS)

    Quinn, Paul; Hong, Daniel C.; Both, Joseph

    2003-03-01

    Popcorn is an extremely popular snack food in the world today. Thermodynamics can be used to analyze how popcorn is produced. By treating the popping mechanism of the corn as a thermodynamic expansion, a method of increasing the volume or size of a kernel of popcorn can be studied. By lowering the pressure surrounding the unpopped kernel, one can use a thermodynamic argument to show that the expanded volume of the kernel when it pops must increase. In this project, a variety of experiments are run to test the validity of this theory. The results show that there is a significant increase in the average kernel size when the pressure of the surroundings is reduced.

  17. Increasing the size of a piece of popcorn

    NASA Astrophysics Data System (ADS)

    Quinn, Paul V.; Hong, Daniel C.; Both, J. A.

    2005-08-01

    Popcorn is an extremely popular snack food in the world today. Thermodynamics can be used to analyze how popcorn is produced. By treating the popping mechanism of the corn as a thermodynamic expansion, a method of increasing the volume or size of a kernel of popcorn can be studied. By lowering the pressure surrounding the unpopped kernel, one can use a thermodynamic argument to show that the expanded volume of the kernel when it pops must increase. In this project, a variety of experiments are run to test the qualitative validity of this theory. The results show that there is a significant increase in the average kernel size when the pressure of the surroundings is reduced.

  18. Not letting the left leg know what the right leg is doing: limb-specific locomotor adaptation to sensory-cue conflict.

    PubMed

    Durgin, Frank H; Fox, Laura F; Hoon Kim, Dong

    2003-11-01

    We investigated the phenomenon of limb-specific locomotor adaptation in order to adjudicate between sensory-cue-conflict theory and motor-adaptation theory. The results were consistent with cue-conflict theory in demonstrating that two different leg-specific hopping aftereffects are modulated by the presence of conflicting estimates of self-motion from visual and nonvisual sources. Experiment 1 shows that leg-specific increases in forward drift during attempts to hop in place on one leg while blindfolded vary according to the relationship between visual information and motor activity during an adaptation to outdoor forward hopping. Experiment 2 shows that leg-specific changes in performance on a blindfolded hopping-to-target task are similarly modulated by the presence of cue conflict during adaptation to hopping on a treadmill. Experiment 3 shows that leg-specific aftereffects from hopping additionally produce inadvertent turning during running in place while blindfolded. The results of these experiments suggest that these leg-specific locomotor aftereffects are produced by sensory-cue conflict rather than simple motor adaptation.

  19. Problems in Education about Violence: Factors Affecting the Perceived Increase in Violent Crime.

    ERIC Educational Resources Information Center

    Mersky, Rebecca A.; Chambliss, Catherine

    Although most national and regional statistics show that violent crimes have been declining, there is a widespread misperception among the public that such crimes are increasing. The Perception and Experience of Violent Crime survey, based on research on actual rates and perceptions of crime, was administered to subjects enrolled in a college…

  20. Multiscale Design and Manufacturing of Hybrid DWCNT-Polymer Fibers

    DTIC Science & Technology

    2016-02-09

    lower temperatures , but further increase of temperature produced insignificant structural changes. The latter effect shows promise for the control...elevated temperatures . Increase in crystallinity was confirmed by XRD experiments. Such nanofibers exhibited size effects for strength and modulus...Schatz group) study of the effects of higher carbonization temperatures . Some promising initial results are being now analyzed experimentally and

  1. The Southern Timber Market to 2040

    Treesearch

    Jeffrey P. Prestemon; Robert C. Abt

    2002-01-01

    Timber market analysis of the South's predominantly private timberland finds that the 13 southern states produce nearly 60 percent of the nation's timber, an increase from the mid-1900s. Projections with the Subregional Timber Supply model show that, despite a 67 percent increase in the area of pine plantations, the South will experience a 2 percent decline...

  2. Retro-dimension-cue benefit in visual working memory.

    PubMed

    Ye, Chaoxiong; Hu, Zhonghua; Ristaniemi, Tapani; Gendron, Maria; Liu, Qiang

    2016-10-24

    In visual working memory (VWM) tasks, participants' performance can be improved by a retro-object-cue. However, previous studies have not investigated whether participants' performance can also be improved by a retro-dimension-cue. Three experiments investigated this issue. We used a recall task with a retro-dimension-cue in all experiments. In Experiment 1, we found benefits from retro-dimension-cues compared to neutral cues. This retro-dimension-cue benefit is reflected in an increased probability of reporting the target, but not in the probability of reporting the non-target, as well as increased precision with which this item is remembered. Experiment 2 replicated the retro-dimension-cue benefit and showed that the length of the blank interval after the cue disappeared did not influence recall performance. Experiment 3 replicated the results of Experiment 2 with a lower memory load. Our studies provide evidence that there is a robust retro-dimension-cue benefit in VWM. Participants can use internal attention to flexibly allocate cognitive resources to a particular dimension of memory representations. The results also support the feature-based storing hypothesis.

  3. Retro-dimension-cue benefit in visual working memory

    PubMed Central

    Ye, Chaoxiong; Hu, Zhonghua; Ristaniemi, Tapani; Gendron, Maria; Liu, Qiang

    2016-01-01

    In visual working memory (VWM) tasks, participants’ performance can be improved by a retro-object-cue. However, previous studies have not investigated whether participants’ performance can also be improved by a retro-dimension-cue. Three experiments investigated this issue. We used a recall task with a retro-dimension-cue in all experiments. In Experiment 1, we found benefits from retro-dimension-cues compared to neutral cues. This retro-dimension-cue benefit is reflected in an increased probability of reporting the target, but not in the probability of reporting the non-target, as well as increased precision with which this item is remembered. Experiment 2 replicated the retro-dimension-cue benefit and showed that the length of the blank interval after the cue disappeared did not influence recall performance. Experiment 3 replicated the results of Experiment 2 with a lower memory load. Our studies provide evidence that there is a robust retro-dimension-cue benefit in VWM. Participants can use internal attention to flexibly allocate cognitive resources to a particular dimension of memory representations. The results also support the feature-based storing hypothesis. PMID:27774983

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

    Warpinski, N.R.

    Stimulation experiments conducted in anisotropic, naturally fractured, tight, lenticular gas sandstones have shown the existence of a dual-leakoff phenomenon. Below a threshold pressure, the leakoff coefficient is very low and fluids are very efficient. Above the threshold, leakoff increased by a factor of 50, slurries dehydrate rapidly, and screenouts occur in minutes. The leakoff has been shown to be controllable to some extent with 100-mesh sand. Results of three stimulation experiments are presented, including a treatment that screened out, a minifracture experiment that showed the effectiveness of 100-mesh sand, and a final successful stimulation.

  5. Dual leakoff beehavior in hydraulic fracturing of tight, lenticular gas sands

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

    Warpinski, N.R.

    Stimulation experiments conducted in anisotropic, naturally fractured, tight, lenticular, gas sandstones have shown the existence of a dual leakoff phenomenon. Below a threshold, leakoff increases by a factor of 50, slurries dehydrate rapidly, and screenouts occur in minutes. The leakoff has been shown to be controllable to some extent with 100-mesh sand. Results of three stimulation experiments are presented; three include a treatment that screened out, a minifrac experiment that showed the effectiveness of 100-mesh sand, and a final successful stimulation. 30 refs., 14 figs., 6 tabs.

  6. Hurricanes and Climate: The U.S. CLIVAR Working Group on Hurricanes

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

    Walsh, Kevin J. E.; Camargo, Suzana J.; Vecchi, Gabriel A.

    While a quantitative climate theory of tropical cyclone formation remains elusive, considerable progress has been made recently in our ability to simulate tropical cyclone climatologies and to understand the relationship between climate and tropical cyclone formation. Climate models are now able to simulate a realistic rate of global tropical cyclone formation, although simulation of the Atlantic tropical cyclone climatology remains challenging unless horizontal resolutions finer than 50 km are employed. This article summarizes published research from the idealized experiments of the Hurricane Working Group of U.S. Climate and Ocean: Variability, Predictability and Change (CLIVAR). This work, combined with results frommore » other model simulations, has strengthened relationships between tropical cyclone formation rates and climate variables such as midtropospheric vertical velocity, with decreased climatological vertical velocities leading to decreased tropical cyclone formation. Systematic differences are shown between experiments in which only sea surface temperature is increased compared with experiments where only atmospheric carbon dioxide is increased. Experiments where only carbon dioxide is increased are more likely to demonstrate a decrease in tropical cyclone numbers, similar to the decreases simulated by many climate models for a future, warmer climate. Experiments where the two effects are combined also show decreases in numbers, but these tend to be less for models that demonstrate a strong tropical cyclone response to increased sea surface temperatures. Lastly, further experiments are proposed that may improve our understanding of the relationship between climate and tropical cyclone formation, including experiments with two-way interaction between the ocean and the atmosphere and variations in atmospheric aerosols.« less

  7. Hurricanes and Climate: The U.S. CLIVAR Working Group on Hurricanes

    DOE PAGES

    Walsh, Kevin J. E.; Camargo, Suzana J.; Vecchi, Gabriel A.; ...

    2015-06-01

    While a quantitative climate theory of tropical cyclone formation remains elusive, considerable progress has been made recently in our ability to simulate tropical cyclone climatologies and to understand the relationship between climate and tropical cyclone formation. Climate models are now able to simulate a realistic rate of global tropical cyclone formation, although simulation of the Atlantic tropical cyclone climatology remains challenging unless horizontal resolutions finer than 50 km are employed. This article summarizes published research from the idealized experiments of the Hurricane Working Group of U.S. Climate and Ocean: Variability, Predictability and Change (CLIVAR). This work, combined with results frommore » other model simulations, has strengthened relationships between tropical cyclone formation rates and climate variables such as midtropospheric vertical velocity, with decreased climatological vertical velocities leading to decreased tropical cyclone formation. Systematic differences are shown between experiments in which only sea surface temperature is increased compared with experiments where only atmospheric carbon dioxide is increased. Experiments where only carbon dioxide is increased are more likely to demonstrate a decrease in tropical cyclone numbers, similar to the decreases simulated by many climate models for a future, warmer climate. Experiments where the two effects are combined also show decreases in numbers, but these tend to be less for models that demonstrate a strong tropical cyclone response to increased sea surface temperatures. Lastly, further experiments are proposed that may improve our understanding of the relationship between climate and tropical cyclone formation, including experiments with two-way interaction between the ocean and the atmosphere and variations in atmospheric aerosols.« less

  8. Formation and transformation of chloroform during managed aquifer recharge (MAR).

    PubMed

    Liu, Dan; Liang, Xiujuan; Zhang, Wenjing; Wang, Zhuo; Ma, Tianyi; Li, Fulin; Chen, Xuequn

    2018-05-09

    Chlorination is an effective method to protect the safety of groundwater systems during managed aquifer recharge. However, chlorination leads to the formation of disinfection by-products, whose behavior in aquifers remains unclear and has caused public concern. In this study, an in-site test was performed on an anoxic aquifer in Shouguang City, China, to investigate the formation and transformation of chloroform during managed aquifer recharge. The field tests showed that the formation of chloroform in groundwater caused by the recharge of chlorinated water, and that the fate of chloroform was affected by adsorption and biodegradation. The retardation factor was 1.27, and the half-life was 29 days. The formation and transformation of chloroform during continuous recharge under different hydrochemical conditions was further investigated by batch experiments. These experiments showed that the formation of chloroform increased with contact time, tended to be stable after 10 h, and was facilitated by high chloride/TOC ratios, high pH, and low ionic strength (IS) for a given contact time. The adsorption experiments showed that the process accords with the pseudo-second-order kinetic equations and the Freundlich model. The adsorption capacity was pH dependent (1.01-1.66 μg/g at pH 5 and 2.17-3.05 μg/g at pH 9). Increasing the IS promotes adsorption. The results from biodegradation experiments indicated that the biodegradation was well fitted by the Monod equation. The retardation factor in the batch experiments was close to that of the field test, but the half-life was less than the field test. This is mainly due to the difference in the concentration of dissolved oxygen. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Forest litter crickets prefer higher substrate moisture for oviposition: Evidence from field and lab experiments

    PubMed Central

    Sperber, Carlos Frankl; Albeny-Simões, Daniel; Breaux, Jennifer Ann; Fianco, Marcos; Szinwelski, Neucir

    2017-01-01

    For insects, choosing a favorable oviposition site is a type of parental care, as far as it increases the fitness of its offspring. Niche theory predicts that crickets should show a bell-shaped oviposition response to substrate moisture. However, lab experiments with mole crickets showed a linear oviposition response to substrate moisture. Studies with the house cricket Acheta domesticus also showed a linear juvenile body growth response to water availability, thus adult ovipositing females should respond positively to substrate moisture. We used a field experiment to evaluate the relationship between oviposition preference and substrate moisture in forest litter-dwelling cricket species. We also evaluated oviposition responses to substrate moisture level in Ubiquepuella telytokous, the most abundant litter cricket species in our study area, using a laboratory study. We offered cotton substrate for oviposition which varied in substrate moisture level from zero (i.e., dry) to maximum water absorption capacity. We used two complementary metrics to evaluate oviposition preference: (i) presence or absence of eggs in each sampling unit as binary response variable, and (ii) number of eggs oviposited per sampling unit as count response variable. To test for non-linear responses, we adjusted generalized additive models (GAMM) with mixed effects. We found that both cricket oviposition probability and effort (i.e., number of eggs laid) increased linearly with substrate moisture in the field experiment, and for U. telytokous in the lab experiment. We discarded any non-linear responses. Our results demonstrate the importance of substrate moisture as an ecological niche dimension for litter crickets. This work bolsters knowledge of litter cricket life history association with moisture, and suggests that litter crickets may be particularly threatened by changes in climate that favor habitat drying. PMID:28977023

  10. Forest litter crickets prefer higher substrate moisture for oviposition: Evidence from field and lab experiments.

    PubMed

    de Farias-Martins, Fernando; Sperber, Carlos Frankl; Albeny-Simões, Daniel; Breaux, Jennifer Ann; Fianco, Marcos; Szinwelski, Neucir

    2017-01-01

    For insects, choosing a favorable oviposition site is a type of parental care, as far as it increases the fitness of its offspring. Niche theory predicts that crickets should show a bell-shaped oviposition response to substrate moisture. However, lab experiments with mole crickets showed a linear oviposition response to substrate moisture. Studies with the house cricket Acheta domesticus also showed a linear juvenile body growth response to water availability, thus adult ovipositing females should respond positively to substrate moisture. We used a field experiment to evaluate the relationship between oviposition preference and substrate moisture in forest litter-dwelling cricket species. We also evaluated oviposition responses to substrate moisture level in Ubiquepuella telytokous, the most abundant litter cricket species in our study area, using a laboratory study. We offered cotton substrate for oviposition which varied in substrate moisture level from zero (i.e., dry) to maximum water absorption capacity. We used two complementary metrics to evaluate oviposition preference: (i) presence or absence of eggs in each sampling unit as binary response variable, and (ii) number of eggs oviposited per sampling unit as count response variable. To test for non-linear responses, we adjusted generalized additive models (GAMM) with mixed effects. We found that both cricket oviposition probability and effort (i.e., number of eggs laid) increased linearly with substrate moisture in the field experiment, and for U. telytokous in the lab experiment. We discarded any non-linear responses. Our results demonstrate the importance of substrate moisture as an ecological niche dimension for litter crickets. This work bolsters knowledge of litter cricket life history association with moisture, and suggests that litter crickets may be particularly threatened by changes in climate that favor habitat drying.

  11. Oxytocin increases the influence of public service advertisements.

    PubMed

    Lin, Pei-Ying; Grewal, Naomi Sparks; Morin, Christophe; Johnson, Walter D; Zak, Paul J

    2013-01-01

    This paper presents a neurophysiologic model of effective public service advertisements (PSAs) and reports two experiments that test the model. In Experiment 1, we show that after watching 16 PSAs participants who received oxytocin, compared to those given a placebo, donated to 57% more causes, donated 56% more money, and reported 17% greater concern for those in the ads. In Experiment 2, we measured adrenocorticotropin hormone (ACTH) and oxytocin levels in blood before and after participants watched a PSA. As predicted by the model, donations occurred when participants had increases in both ACTH and oxytocin. Our results indicate that PSAs with social content that cause OT release will be more effective than those that do not. Our results also explain why some individuals do not respond to PSAs.

  12. Oxytocin Increases the Influence of Public Service Advertisements

    PubMed Central

    Lin, Pei-Ying; Grewal, Naomi Sparks; Morin, Christophe; Johnson, Walter D.; Zak, Paul J.

    2013-01-01

    This paper presents a neurophysiologic model of effective public service advertisements (PSAs) and reports two experiments that test the model. In Experiment 1, we show that after watching 16 PSAs participants who received oxytocin, compared to those given a placebo, donated to 57% more causes, donated 56% more money, and reported 17% greater concern for those in the ads. In Experiment 2, we measured adrenocorticotropin hormone (ACTH) and oxytocin levels in blood before and after participants watched a PSA. As predicted by the model, donations occurred when participants had increases in both ACTH and oxytocin. Our results indicate that PSAs with social content that cause OT release will be more effective than those that do not. Our results also explain why some individuals do not respond to PSAs. PMID:23460821

  13. Primary healthcare nurses' experiences with motivational interviewing in health promotion practice.

    PubMed

    Brobeck, Elisabeth; Bergh, Håkan; Odencrants, Sigrid; Hildingh, Cathrine

    2011-12-01

    The aim of the study was to describe primary healthcare nurses' experiences with motivational interviewing as a method for health promotion practice. A person's lifestyle has a major effect on his or her health. Motivational interviewing is one way of working with lifestyle changes in health promotion practice. The basic plan of motivational interviewing is to help people understand their lifestyle problems and make positive lifestyle changes. Motivational interviewing has been proven to be more effective than conventional methods in increasing patient motivation. This study has a descriptive design and uses a qualitative method. Twenty nurses who worked in primary health care and actively used motivational interviewing in their work were interviewed. Qualitative content analysis was used to process the data. The primary healthcare nurses' experiences with motivational interviewing as a method of health promotion practice demonstrate that motivational interviewing is a demanding, enriching and useful method that promotes awareness and guidance in the care relationship. The results also show that motivational interviewing is a valuable tool for primary healthcare nurses' health promotion practice. This study shows that motivational interviewing places several different demands on nurses who use this method. Those who work with motivational interviewing must make an effort to incorporate this new method to avoid falling back into the former practice of simply giving advice. Maintaining an open mind while implementing motivational interviewing in real healthcare settings is crucial for nurses to increase this method's effectiveness. The nurses in the study had a positive experience with motivational interviewing, which can contribute to the increased use, adaption and development of motivational interviewing among primary healthcare professionals. Increased motivational interviewing knowledge and skills would also contribute to promotion of health lifestyle practices. © 2011 Blackwell Publishing Ltd.

  14. DNA Repair and the Evolution of Transformation in Bacillus Subtilis. II. Role of Inducible Repair

    PubMed Central

    Wojciechowski, M. F.; Hoelzer, M. A.; Michod, R. E.

    1989-01-01

    In Bacillus subtilis, DNA repair and recombination are intimately associated with competence, the physiological state in which the bacterium can bind, take up and recombine exogenous DNA. Previously, we have shown that the homologous DNA transformation rate (ratio of transformants to total cells) increases with increasing UV dosage if cells are transformed after exposure to UV radiation (UV-DNA), whereas the transformation rate decreases if cells are transformed before exposure to UV (DNA-UV). In this report, by using different DNA repair-deficient mutants, we show that the greater increase in transformation rate in UV-DNA experiments than in DNA-UV experiments does not depend upon excision repair or inducible SOS-like repair, although certain quantitative aspects of the response do depend upon these repair systems. We also show that there is no increase in the transformation rate in a UV-DNA experiment when repair and recombination proficient cells are transformed with nonhomologous plasmid DNA, although the results in a DNA-UV experiment are essentially unchanged by using plasmid DNA. We have used din operon fusions as a sensitive means of assaying for the expression of genes under the control of the SOS-like regulon in both competent and noncompetent cell subpopulations as a consequence of competence development and our subsequent experimental treatments. Results indicate that the SOS-like system is induced in both competent and noncompetent subpopulations in our treatments and so should not be a major factor in the differential response in transformation rate observed in UV-DNA and DNA-UV treatments. These results provide further support to the hypothesis that the evolutionary function of competence is to bring DNA into the cell for use as template in the repair of DNA damage. PMID:2497048

  15. Does the growth response of woody plants to elevated CO2 increase with temperature? A model-oriented meta-analysis.

    PubMed

    Baig, Sofia; Medlyn, Belinda E; Mercado, Lina M; Zaehle, Sönke

    2015-12-01

    The temperature dependence of the reaction kinetics of the Rubisco enzyme implies that, at the level of a chloroplast, the response of photosynthesis to rising atmospheric CO2 concentration (Ca ) will increase with increasing air temperature. Vegetation models incorporating this interaction predict that the response of net primary productivity (NPP) to elevated CO2 (eCa ) will increase with rising temperature and will be substantially larger in warm tropical forests than in cold boreal forests. We tested these model predictions against evidence from eCa experiments by carrying out two meta-analyses. Firstly, we tested for an interaction effect on growth responses in factorial eCa  × temperature experiments. This analysis showed a positive, but nonsignificant interaction effect (95% CI for above-ground biomass response = -0.8, 18.0%) between eCa and temperature. Secondly, we tested field-based eCa experiments on woody plants across the globe for a relationship between the eCa effect on plant biomass and mean annual temperature (MAT). This second analysis showed a positive but nonsignificant correlation between the eCa response and MAT. The magnitude of the interactions between CO2 and temperature found in both meta-analyses were consistent with model predictions, even though both analyses gave nonsignificant results. Thus, we conclude that it is not possible to distinguish between the competing hypotheses of no interaction vs. an interaction based on Rubisco kinetics from the available experimental database. Experiments in a wider range of temperature zones are required. Until such experimental data are available, model predictions should aim to incorporate uncertainty about this interaction. © 2015 John Wiley & Sons Ltd.

  16. Electric analog studies of flow to wells in the Punjab aquifer of West Pakistan

    USGS Publications Warehouse

    Mundorff, Maurice John; Bennett, G.D.; Ahmad, Masood

    1972-01-01

    A series of experiments was performed with a steady-state electric analog simulating a cylindrical segment of the aquifer underlying the plains of the Punjab region of West Pakistan. In most of the experiments recharge was assumed to be from the surface, within a specified radius of influence, and distributed uniformly over the area within this radius. Experiments were made with different anisotropies (ratios of lateral to vertical resistance) so that various possible combinations of aquifer thickness and effective radius or radius of influence and combinations .of lateral and vertical permeability could be included in the models. Flow nets were constructed to show distribution of potential in the vertical section and intersections of stream surfaces with the vertical plane. The series of experiments in which the screened interval is in the upper part of the aquifer shows that flow decreases and stream tubes shift progressively toward the upper part of the aquifer as anisotropy increases. Another series illustrates that total yield increases and yield per foot of screen decreases as screen length increases. The experiments indicate that, under conditions prevalent in the Punjab, the Distance-drawdown method for determining permeability gives results with an error of 10 percent or less provided that at least one piezometer or observation well is within a few feet of the pumped well and that no observation well or piezometer used is more than 100 feet from the pumped well. Relative traveltime for each of 10 stream tubes is given for three models. Relative traveltimes for one-fourth and one-half the effective radius are given for selected stream tubes. By substituting values for the aquifer parameters, actual traveltimes are computed from the relative-traveltime data.

  17. Mary Poppins was right: Adding small amounts of sugar or salt reduces the bitterness of vegetables.

    PubMed

    Bakke, Alyssa J; Stubbs, Cody A; McDowell, Elliott H; Moding, Kameron J; Johnson, Susan L; Hayes, John E

    2018-07-01

    Only a quarter of adults and 7% of children consume recommended amounts of vegetables each day. Often vegetables are not initially palatable due to bitterness, which may lead children and adults to refuse to taste or eat them. The objective of this research was to determine if very small amounts of sugar or salt (common household ingredients) could lead to significant reductions in bitterness intensity and increased hedonic ratings of green vegetable purees. For Experiment 1, three different green vegetable purees (broccoli, spinach, and kale) were prepared with different levels of sugar (0%, 0.6%, 1.2%, and 1.8%) or salt (0 and 0.2%). Samples were evaluated using standard descriptive analysis techniques with nine adults who completed more than 20 h of green vegetable specific training as a group. For Experiment 2, each vegetable puree was prepared with either 0% or 2% sugar, and bitterness was assessed via a forced choice task with 84 adults. For Experiment 3, each vegetable puree was prepared with 0%, 1%, or 2% sugar and rated for liking on standard 9 point hedonic scales by 99 adults. Experiments 1 and 2 showed that addition of small amounts of sugar and salt each reduced the bitterness (and increased sweetness and saltiness) from all three vegetables without altering other sensory properties (e.g. texture or aroma). Experiment 3 showed that adding sugar to vegetable purees increased hedonic ratings for adult consumers. We also found parents had mixed attitudes about the idea of adding sugar to foods intended for infants and toddlers. Further research on the effects of bitterness masking especially for specific populations (e.g., infants and young children or adults who have higher sensitivity to bitter taste) is warranted. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. JPRS Report, Science & Technology, USSR: Life Sciences.

    DTIC Science & Technology

    1987-08-04

    alpha 2 preparation, produced by E. coli cells, is described and discussed. Cytokinin activity was determined by inducement of betacyanin synthesis in...the dark by cytokinin in the presence of thyrosine, used as a substrate. Experiments with A. caudatus sprouts showed that IFN alpha 2 produced...of IFN- alpha 2 appeared at concentration of 0.1 unit/ml but increase of concentration reduced cytokinin activity. In control experiments, induction

  19. Dynamic Experiments and Constitutive Model Performance for Polycarbonate

    DTIC Science & Technology

    2014-07-01

    phase disabled. Note, positive stress is tensile and negative is compressive ....28 Figure 23. Parameter sensitivity showing numerical contours of axial ... compressive . For the no alpha and no beta cases shown in the axial stress plots of figure 23 at 40 s, an increase in radial compression as compared...traditional Taylor cylinder impact experiment, which achieves large strain and high-strain-rate deformation but under hydrostatic compression

  20. An Objective Measurement of the Build-Up of Auditory Streaming and of Its Modulation by Attention

    ERIC Educational Resources Information Center

    Thompson, Sarah K.; Carlyon, Robert P.; Cusack, Rhodri

    2011-01-01

    Three experiments studied auditory streaming using sequences of alternating "ABA" triplets, where "A" and "B" were 50-ms tones differing in frequency by [delta]f semitones and separated by 75-ms gaps. Experiment 1 showed that detection of a short increase in the gap between a B tone and the preceding A tone, imposed on one ABA triplet, was better…

  1. Plasma-assisted oxide removal from ruthenium-coated EUV optics

    NASA Astrophysics Data System (ADS)

    Dolgov, A.; Lee, C. J.; Bijkerk, F.; Abrikosov, A.; Krivtsun, V. M.; Lopaev, D.; Yakushev, O.; van Kampen, M.

    2018-04-01

    An experimental study of oxide reduction at the surface of ruthenium layers on top of multilayer mirrors and thin Ru/Si films is presented. Oxidation and reduction processes were observed under conditions close to those relevant for extreme ultraviolet lithography. The oxidized ruthenium surface was exposed to a low-temperature hydrogen plasma, similar to the plasma induced by extreme ultraviolet radiation. The experiments show that hydrogen ions are the main reducing agent. Furthermore, the addition of hydrogen radicals increases the reduction rate beyond that expected from simple flux calculations. We show that low-temperature hydrogen plasmas can be effective for reducing oxidized top surfaces. Our proof-of-concept experiments show that an in situ, EUV-generated plasma cleaning technology is feasible.

  2. Improving fast-ion confinement in high-performance discharges by suppressing Alfvén eigenmodes

    DOE PAGES

    Kramer, Geritt J.; Podestà, Mario; Holcomb, Christopher; ...

    2017-03-28

    Here, we show that the degradation of fast-ion confinement in steady-state DIII-D discharges is quantitatively consistent with predictions based on the effects of multiple unstable Alfven eigenmodes on beam-ion transport. Simulation and experiment show that increasing the radius where the magnetic safety factor has its minimum is effective in minimizing beam-ion transport. This is favorable for achieving high performance steady-state operation in DIII-D and future reactors. A comparison between the experiments and a critical gradient model, in which only equilibrium profiles were used to predict the most unstable modes, show that in a number of cases this model reproduces themore » measured neutron rate well.« less

  3. Hyperthermal atomic oxygen generator

    NASA Technical Reports Server (NTRS)

    Khandelwal, Govind S.; Wu, Dongchuan

    1990-01-01

    Characterization of the transport properties of oxygen through silver was continued. Specifically, experiments measuring the transport through Ag(111), Ag(110), Ag(100) single crystals and through Ag0.05 Zr alloy were completed. In addition, experiments using glow discharge excitation of oxygen to assist in the transport were completed. It was found that the permeability through the different orientations of single crystal Ag was the same, but significant differences existed in the diffusivity. The experimental ratio of diffusivities, however, was in reasonable agreement with theoretical estimates. Since the solubilities of orientations must be the same, this suggests some problems with the assumption K = DS. The glow discharge experiments show that there is a substantial increase in transport (factor of six) when the upstream pressure is dissociated to some fraction of atoms (which have a much higher sticking coefficient). These results indicate that there is a significant surface limitation because of dissociative adsorption of the molecules. Experiments with the Ag0.05 Zr alloy and its high-grain boundary and defect density show a permeability of greater than a factor of two over ordinary polycrystalline Ag, but it is unclear as to whether this is because of enhanced transport through these defects or whether the Zr and defects on the surface increased the sticking coefficient and therefore the transport.

  4. Evaluative conditioning increases with temporal contiguity. The influence of stimulus order and stimulus interval on evaluative conditioning.

    PubMed

    Gast, Anne; Langer, Sebastian; Sengewald, Marie-Ann

    2016-10-01

    Evaluative conditioning (EC) is a change in valence that is due to pairing a conditioned stimulus (CS) with another, typically valent, unconditioned stimulus (US). This paper investigates how basic presentation parameters moderate EC effects. In two studies we tested the effectiveness of different temporal relations of the CS and the US, that is, the order in which the stimuli were presented and the temporal distance between them. Both studies showed that the size of EC effects was independent of the presentation order of CS and US within a stimulus pair. Contrary to classical conditioning effects, EC effects are thus not most pronounced after CS-first presentations. Furthermore, as shown in Experiment 2, EC effects increased in magnitude as the temporal interval between CS and US presentations decreased. Experiment 1 showed largest EC effects in the condition with simultaneous presentations - which can be seen as the condition with the temporally closest presentation. In this Experiment stimuli were presented in two different modalities, which might have facilitated simultaneous processing. In Experiment 2, in which all stimuli were presented visually, this advantage of simultaneous presentation was not found. We discuss practical and theoretical implications of our findings. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Experiment "Regeneration" Performed Aboard the Russian Spacecraft Foton-M2 in 2005

    NASA Technical Reports Server (NTRS)

    Grigoryan, Elonora; Almeida, Eduardo; Domaratskaya, Elena; Poplinskaya, Valentina; Aleinikova, Karina; Tairbekov, Murad; Mitashov, Victor

    2006-01-01

    The experiments on the newts performed earlier aboard Russian biosate llites showed that the rate of lens and tail regeneration in space wa s greater than on the ground. In parallel it was found that the numbe r of cells in S-phase was greater in space-flown animals than in the ground controls. However, it was unclear whether cell proliferation stimulation was induced by micro-g per se. Molecular mechanisms under lying the change also remained obscure. These issues were addressed b y the joint Russian-American experiment "Regeneration" flown on Foton -M2 in 2005. The method for in-flight delivering DNA precursor BrdU was developed. The experiment showed that during the flight the numbe r of S-phase cells in the regenerating eyes and tails increased. Thes e data together with those obtained earlier suggest that cell prolife ration increases in response to the effects of both micro-g and 1-g a fter return to Earth. The expression of bFGF in regenerating tissues of "flown" newts and ground controls was examined using immuno-histo chemistry. Obtained results suggest that this growth factor is a part icipant of the promotional effect of space flight upon cell prolifera tion in lens and tail regenerates.

  6. Effect of manure and plants spacing on yield and flavonoid content of Elephantopus scaber L.

    NASA Astrophysics Data System (ADS)

    Riyana, D.; Widiyastuti, Y.; Widodo, H.; Purwanto, E.; Samanhudi

    2018-03-01

    This experiment is aimed to observe the growth and flavonoid contain of Tapak Liman (Elephantopus scaber L.) with different manure types and plants spacing treatment. This experiment is conducted at Tegal Gede Village, Karanganyar District on June until August 2016. The analysis of secondary metabolism was done in B2P2TOOT, Tawangamangu. This experiment is conducted with Randomized Complete Block Design (RCBD) with two treatment factors, those are manure and plants spacing. Animal manure treatment had 3 levels, those are without manure, cow manure with 20 ton/ha dose, and chicken manure with 20 ton/ha dose. Plants spacing treatment had 3 phrase, those are 20 cm × 20 cm; 30 × 30 cm; 40 cm × 40 cm. The result of this experiment shows that chicken manure with 20 ton/ha dosage increase the development of leaves’ lengthiness, header’s diameter, plant’s fresh weight, and plant’s dry weight. Plants spacing 40 cm × 40 cm increase for the development of leaves’ lengthiness, header’s diameter, plant’s wet weight, and plant’s dry weight. The combination between chicken manure with 20 ton/ha dose and plants spacing 40 cm × 40cm treatments show the highest amount of tapak liman extract and alleged having the biggest amount of flavonoid substance.

  7. Retention of neodymium by dolomite at variable ionic strength as probed by batch and column experiments.

    PubMed

    Emerson, H P; Zengotita, F; Richmann, M; Katsenovich, Y; Reed, D T; Dittrich, T M

    2018-10-01

    The results presented in this paper highlight the complexity of adsorption and incorporation processes of Nd with dolomite and significantly improve upon previous work investigating trivalent actinide and lanthanide interactions with dolomite. Both batch and mini column experiments were conducted at variable ionic strength. These data highlight the strong chemisorption of Nd to the dolomite surface (equilibrium K d 's > 3000 mL/g) and suggest that equilibrium adsorption processes may not be affected by ionic strength based on similar results at 0.1 and 5.0 M ionic strength in column breakthrough and equilibrium batch (>5 days) results. Mini column experiments conducted over approximately one year also represent a significant development in measurement of sorption of Nd in the presence of flow as previous large-scale column experiments did not achieve breakthrough likely due to the high loading capacity of dolomite for Nd (up to 240 μg/g). Batch experiments in the absence of flow show that the rate of Nd removal increases with increasing ionic strength (up to 5.0 M) with greater removal at greater ionic strength for a 24 h sampling point. We suggest that the increasing ionic strength induces increased mineral dissolution and re-precipitation caused by changes in activity with ionic strength that lead to increased removal of Nd through co-precipitation processes. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Insights about transport mechanisms and fracture flow channeling from multi-scale observations of tracer dispersion in shallow fractured crystalline rock.

    PubMed

    Guihéneuf, N; Bour, O; Boisson, A; Le Borgne, T; Becker, M W; Nigon, B; Wajiduddin, M; Ahmed, S; Maréchal, J-C

    2017-11-01

    In fractured media, solute transport is controlled by advection in open and connected fractures and by matrix diffusion that may be enhanced by chemical weathering of the fracture walls. These phenomena may lead to non-Fickian dispersion characterized by early tracer arrival time, late-time tailing on the breakthrough curves and potential scale effect on transport processes. Here we investigate the scale dependency of these processes by analyzing a series of convergent and push-pull tracer experiments with distance of investigation ranging from 4m to 41m in shallow fractured granite. The small and intermediate distances convergent experiments display a non-Fickian tailing, characterized by a -2 power law slope. However, the largest distance experiment does not display a clear power law behavior and indicates possibly two main pathways. The push-pull experiments show breakthrough curve tailing decreases as the volume of investigation increases, with a power law slope ranging from -3 to -2.3 from the smallest to the largest volume. The multipath model developed by Becker and Shapiro (2003) is used here to evaluate the hypothesis of the independence of flow pathways. The multipath model is found to explain the convergent data, when increasing local dispersivity and reducing the number of pathways with distance which suggest a transition from non-Fickian to Fickian transport at fracture scale. However, this model predicts an increase of tailing with push-pull distance, while the experiments show the opposite trend. This inconsistency may suggest the activation of cross channel mass transfer at larger volume of investigation, which leads to non-reversible heterogeneous advection with scale. This transition from independent channels to connected channels when the volume of investigation increases suggest that both convergent and push-pull breakthrough curves can inform the existence of characteristic length scales. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Insights about transport mechanisms and fracture flow channeling from multi-scale observations of tracer dispersion in shallow fractured crystalline rock

    NASA Astrophysics Data System (ADS)

    Guihéneuf, N.; Bour, O.; Boisson, A.; Le Borgne, T.; Becker, M. W.; Nigon, B.; Wajiduddin, M.; Ahmed, S.; Maréchal, J.-C.

    2017-11-01

    In fractured media, solute transport is controlled by advection in open and connected fractures and by matrix diffusion that may be enhanced by chemical weathering of the fracture walls. These phenomena may lead to non-Fickian dispersion characterized by early tracer arrival time, late-time tailing on the breakthrough curves and potential scale effect on transport processes. Here we investigate the scale dependency of these processes by analyzing a series of convergent and push-pull tracer experiments with distance of investigation ranging from 4 m to 41 m in shallow fractured granite. The small and intermediate distances convergent experiments display a non-Fickian tailing, characterized by a -2 power law slope. However, the largest distance experiment does not display a clear power law behavior and indicates possibly two main pathways. The push-pull experiments show breakthrough curve tailing decreases as the volume of investigation increases, with a power law slope ranging from - 3 to - 2.3 from the smallest to the largest volume. The multipath model developed by Becker and Shapiro (2003) is used here to evaluate the hypothesis of the independence of flow pathways. The multipath model is found to explain the convergent data, when increasing local dispersivity and reducing the number of pathways with distance which suggest a transition from non-Fickian to Fickian transport at fracture scale. However, this model predicts an increase of tailing with push-pull distance, while the experiments show the opposite trend. This inconsistency may suggest the activation of cross channel mass transfer at larger volume of investigation, which leads to non-reversible heterogeneous advection with scale. This transition from independent channels to connected channels when the volume of investigation increases suggest that both convergent and push-pull breakthrough curves can inform the existence of characteristic length scales.

  10. The interactive effect of social pain and executive functioning on aggression: an fMRI experiment.

    PubMed

    Chester, David S; Eisenberger, Naomi I; Pond, Richard S; Richman, Stephanie B; Bushman, Brad J; Dewall, C Nathan

    2014-05-01

    Social rejection often increases aggression, but the neural mechanisms underlying this effect remain unclear. This experiment tested whether neural activity in the dorsal anterior cingulate cortex (dACC) and anterior insula in response to social rejection predicted greater subsequent aggression. Additionally, it tested whether executive functioning moderated this relationship. Participants completed a behavioral measure of executive functioning, experienced social rejection while undergoing functional magnetic resonance imaging and then completed a task in which they could aggress against a person who rejected them using noise blasts . We found that dACC activation and executive functioning interacted to predict aggression. Specifically, participants with low executive functioning showed a positive association between dACC activation and aggression, whereas individuals with high executive functioning showed a negative association. Similar results were found for the left anterior insula. These findings suggest that social pain can increase or decrease aggression, depending on an individual's regulatory capability.

  11. Experimental research on the infrared gas fire detection system

    NASA Astrophysics Data System (ADS)

    Jiang, Yalong; Liu, Yangyang

    2018-02-01

    Open fires and smoldering fires were differentiated using five experiments: wood pyrolysis, polyurethane smoldering, wood fire, polyurethane fire and cotton rope smoldering. At the same time, the distribution of CO2 and CO concentration in combustion products at different heights was studied. Real fire and environmental interference were distinguished using burning cigarettes and sandalwood. The results showed that open fires and smoldering fires produced significantly different ratios of CO2 and CO concentrations. By judging the order of magnitudes of the ratio CO2 and CO concentrations in the combustion products, open fire and smoldering fire could be effectively distinguished. At the same time, the comparison experiment showed that the rate of increase of the concentration of CO in the smoldering fire was higher than that under non-fire conditions. With the criterion of the rate of increase of CO concentration, smoldering fire and non-fire could be distinguished.

  12. Interactions Between Modality of Working Memory Load and Perceptual Load in Distractor Processing.

    PubMed

    Koshino, Hideya; Olid, Pilar

    2015-01-01

    The present study investigated interactions between working memory load and perceptual load. The load theory (Lavie, Hirst, de Fockert, & Viding, 2004 ) claims that perceptual load decreases distractor interference, whereas working memory load increases interference. However, recent studies showed that effects of working memory might depend on the relationship between modalities of working memory and task stimuli. Here, we examined whether the relationship between working memory load and perceptual load would remain the same across modalities. The results of Experiment 1 showed that verbal working memory load did not affect a compatibility effect for low perceptual load, whereas it increased the compatibility effect for high perceptual load. In Experiment 2, the compatibility effect remained the same regardless of visual working memory load. These results suggest that the effects of working memory load and perceptual load depend on the relationship between the modalities of working memory and stimuli.

  13. Effects of perceptual similarity but not semantic association on false recognition in aging

    PubMed Central

    Gill, Emma

    2017-01-01

    This study investigated semantic and perceptual influences on false recognition in older and young adults in a variant on the Deese-Roediger-McDermott paradigm. In two experiments, participants encoded intermixed sets of semantically associated words, and sets of unrelated words. Each set was presented in a shared distinctive font. Older adults were no more likely to falsely recognize semantically associated lure words compared to unrelated lures also presented in studied fonts. However, they showed an increase in false recognition of lures which were related to studied items only by a shared font. This increased false recognition was associated with recollective experience. The data show that older adults do not always rely more on prior knowledge in episodic memory tasks. They converge with other findings suggesting that older adults may also be more prone to perceptually-driven errors. PMID:29302398

  14. Mesocosms Reveal Ecological Surprises from Climate Change.

    PubMed

    Fordham, Damien A

    2015-12-01

    Understanding, predicting, and mitigating the impacts of climate change on biodiversity poses one of the most crucial challenges this century. Currently, we know more about how future climates are likely to shift across the globe than about how species will respond to these changes. Two recent studies show how mesocosm experiments can hasten understanding of the ecological consequences of climate change on species' extinction risk, community structure, and ecosystem functions. Using a large-scale terrestrial warming experiment, Bestion et al. provide the first direct evidence that future global warming can increase extinction risk for temperate ectotherms. Using aquatic mesocosms, Yvon-Durocher et al. show that human-induced climate change could, in some cases, actually enhance the diversity of local communities, increasing productivity. Blending these theoretical and empirical results with computational models will improve forecasts of biodiversity loss and altered ecosystem processes due to climate change.

  15. The Influence of Topic Status on Written and Spoken Sentence Production

    PubMed Central

    Cowles, H. Wind; Ferreira, Victor S.

    2012-01-01

    Four experiments investigate the influence of topic status and givenness on how speakers and writers structure sentences. The results of these experiments show that when a referent is previously given, it is more likely to be produced early in both sentences and word lists, confirming prior work showing that givenness increases the accessibility of given referents. When a referent is previously given and assigned topic status, it is even more likely to be produced early in a sentence, but not in a word list. Thus, there appears to be an early mention advantage for topics that is present in both written and spoken modalities, but is specific to sentence production. These results suggest that information-structure constructs like topic exert an influence that is not based only on increased accessibility, but also reflects mapping to syntactic structure during sentence production. PMID:22408281

  16. Overcoming beneficiary race as an impediment to charitable donations: social dominance orientation, the experience of moral elevation, and donation behavior.

    PubMed

    Freeman, Dan; Aquino, Karl; McFerran, Brent

    2009-01-01

    Three studies examined the relationship between social dominance orientation (SDO), the experience of moral elevation, and Whites' donations to charitable organizations. Study 1 used video clips depicting acts of moral excellence to elicit a state of moral elevation (a distinctive feeling of warmth and expansion, which is accompanied by admiration, affection, and even love for people whose exemplary moral behavior is being observed). Results show that moral elevation increased participants' willingness to donate to a Black-oriented charity and attenuated the negative effect of the group-based dominance (GBD) component of SDO on donation behavior. Studies 2 and 3 replicate and extend these findings by using a written story to elicit a state of moral elevation and examining actual donations to a Black-oriented charity. Results show that moral elevation increased donations to the Black-oriented charity and neutralized the negative influence of GBD.

  17. Freely Chosen Index Finger Tapping Frequency Is Increased in Repeated Bouts of Tapping.

    PubMed

    Hansen, Ernst Albin; Ebbesen, Brian Duborg; Dalsgaard, Ane; Mora-Jensen, Mark Holten; Rasmussen, Jakob

    2015-01-01

    Healthy individuals (n = 40) performed index finger tapping at freely chosen frequency during repeated bouts and before and after near-maximal muscle action consisting of 3 intense flexions of the index finger metacarpal phalangeal joint. One experiment showed, unexpectedly, that a bout of tapping increased the tapping frequency in the subsequent bout. Thus, a cumulating increase of 8.2 ± 5.4% (p < .001) occurred across 4 bouts, which were all separated by 10 min rest periods. Follow-up experiments revealed that tapping frequency was still increased in consecutive bouts when rest periods were extended to 20 min. Besides, near-maximal muscle activation, followed by 5 min rest, did not affect the tapping frequency. In conclusion, freely chosen tapping frequency was increased in repeated bouts of tapping, which were separated by 10-20 min rest periods. The observed phenomenon is suggested to be termed repeated bout rate enhancement.

  18. Three decades of research at Flakaliden advancing whole-tree physiology, forest ecosystem and global change research.

    PubMed

    Ryan, Michael G

    2013-11-01

    Nutrient supply often limits growth in forest ecosystems and may limit the response of growth to an increase in other resources, or to more favorable environmental factors such as temperature and soil water. To explore the consequences and mechanisms of optimum nutrient supply for forest growth, the Flakaliden research site was established in 1986 on a young Norway spruce site with nutrient-poor soil. This special section on research at Flakaliden presents five papers that explore different facets of nutrition, atmospheric CO2 concentration, [CO2], and increased temperature treatments, using the original experiment as a base. Research at Flakaliden shows the dominant role of nutrition in controlling the response of growth to the increased photosynthesis promoted by elevated [CO2] and temperature. Experiments with whole-tree chambers showed that all treatments (air temperature warming, elevated [CO2] and optimum nutrition) increased shoot photosynthesis by 30-50%, but growth only increased with [CO2] when combined with the optimum nutrition treatment. Elevated [CO2] and temperature increased shoot photosynthesis by increasing the slope between light-saturated photosynthesis and foliar nitrogen by 122%, the initial slope of the light response curve by 52% and apparent quantum yield by 10%. Optimum nutrition also decreased photosynthetic capacity by 17%, but increased it by 62% in elevated [CO2], as estimated from wood δ(13)C. Elevated air temperature advanced spring recovery of photosynthesis by 37%, but spring frost events remained the controlling factor for photosynthetic recovery, and elevated [CO2] did not affect this. Increased nutrient availability increased wood growth primarily through a 50% increase in tracheid formation, mostly during the peak growth season. Other notable contributions of research at Flakaliden include exploring the role of optimal nutrition in large-scale field trials with foliar analysis, using an ecosystem approach for multifactor experiments, development of whole-tree chambers allowing inexpensive environmental manipulations, long-term deployment of shoot chambers for continuous measurements of gas exchange and exploring the ecosystem response to soil and aboveground tree warming. The enduring legacy of Flakaliden will be the rich data set of long-term, multifactor experiments that has been and will continue to be used in many modeling and cross-site comparison studies.

  19. Effects of temperature and photoperiod on postponing bermudagrass (Cynodon dactylon [L.] Pers.) turf dormancy.

    PubMed

    Esmaili, Somayeh; Salehi, Hassan

    2012-06-15

    Growth chamber and field experiments were carried out to determine the effects of extended photoperiod under low and freezing temperatures on bermudagrass turf dormancy at Bajgah, in the southern part of Iran. The experiment in the growth chamber was conducted with four temperature regimes (15, 7.5, 0 and -7.5°C) and three light durations (8, 12 and 16h) in a completely randomized design with four replications. The field study was conducted in two consecutive years (2008-2009) with three light durations (8, 12 and 16h) in months with natural short day length and arranged in a randomized complete blocks design with three replications. Results in both experiments showed that decreasing temperature and photoperiod decreased verdure fresh and dry weight, shoot height, tiller density, leaf area and chlorophyll and relative water contents (RWC). However, rooting depth and fresh weight of roots increased in the growth chamber. Decreasing the temperature and light duration increased electrolyte leakage and proline content. Reducing sugars increased with decreasing temperature and declined with lowering light duration in both shoots and roots. Starch content of both shoots and roots showed an adverse trend compared to reducing sugars; starch content increased in both shoots and roots in all treatments by shortening the photoperiod. Practically, the problem of bermudagrass turf's dormancy could be solved via increasing the photoperiod in months with short day lengths. This treatment would be efficient and useful for turfgrass managers to apply in landscapes and stadiums. Copyright © 2012 Elsevier GmbH. All rights reserved.

  20. Reproductive experience modified dendritic spines on cortical pyramidal neurons to enhance sensory perception and spatial learning in rats.

    PubMed

    Chen, Jeng-Rung; Lim, Seh Hong; Chung, Sin-Cun; Lee, Yee-Fun; Wang, Yueh-Jan; Tseng, Guo-Fang; Wang, Tsyr-Jiuan

    2017-01-27

    Behavioral adaptations during motherhood are aimed at increasing reproductive success. Alterations of hormones during motherhood could trigger brain morphological changes to underlie behavioral alterations. Here we investigated whether motherhood changes a rat's sensory perception and spatial memory in conjunction with cortical neuronal structural changes. Female rats of different statuses, including virgin, pregnant, lactating, and primiparous rats were studied. Behavioral test showed that the lactating rats were most sensitive to heat, while rats with motherhood and reproduction experience outperformed virgin rats in a water maze task. By intracellular dye injection and computer-assisted 3-dimensional reconstruction, the dendritic arbors and spines of the layer III and V pyramidal neurons of the somatosensory cortex and CA1 hippocampal pyramidal neurons were revealed for closer analysis. The results showed that motherhood and reproductive experience increased dendritic spines but not arbors or the lengths of the layer III and V pyramidal neurons of the somatosensory cortex and CA1 hippocampal pyramidal neurons. In addition, lactating rats had a higher incidence of spines than pregnant or primiparous rats. The increase of dendritic spines was coupled with increased expression of the glutamatergic postsynaptic marker protein (PSD-95), especially in lactating rats. On the basis of the present results, it is concluded that motherhood enhanced rat sensory perception and spatial memory and was accompanied by increases in dendritic spines on output neurons of the somatosensory cortex and CA1 hippocampus. The effect was sustained for at least 6 weeks after the weaning of the pups.

  1. The emotional power of music: how music enhances the feeling of affective pictures.

    PubMed

    Baumgartner, Thomas; Lutz, Kai; Schmidt, Conny F; Jäncke, Lutz

    2006-02-23

    Music is an intriguing stimulus widely used in movies to increase the emotional experience. However, no brain imaging study has to date examined this enhancement effect using emotional pictures (the modality mostly used in emotion research) and musical excerpts. Therefore, we designed this functional magnetic resonance imaging study to explore how musical stimuli enhance the feeling of affective pictures. In a classical block design carefully controlling for habituation and order effects, we presented fearful and sad pictures (mostly taken from the IAPS) either alone or combined with congruent emotional musical excerpts (classical pieces). Subjective ratings clearly indicated that the emotional experience was markedly increased in the combined relative to the picture condition. Furthermore, using a second-level analysis and regions of interest approach, we observed a clear functional and structural dissociation between the combined and the picture condition. Besides increased activation in brain areas known to be involved in auditory as well as in neutral and emotional visual-auditory integration processes, the combined condition showed increased activation in many structures known to be involved in emotion processing (including for example amygdala, hippocampus, parahippocampus, insula, striatum, medial ventral frontal cortex, cerebellum, fusiform gyrus). In contrast, the picture condition only showed an activation increase in the cognitive part of the prefrontal cortex, mainly in the right dorsolateral prefrontal cortex. Based on these findings, we suggest that emotional pictures evoke a more cognitive mode of emotion perception, whereas congruent presentations of emotional visual and musical stimuli rather automatically evoke strong emotional feelings and experiences.

  2. Cortical activation changes underlying stimulation-induced behavioural gains in chronic stroke

    PubMed Central

    Bachtiar, Velicia; O'Shea, Jacinta; Allman, Claire; Bosnell, Rosemary Ann; Kischka, Udo; Matthews, Paul McMahan; Johansen-Berg, Heidi

    2012-01-01

    Transcranial direct current stimulation, a form of non-invasive brain stimulation, is showing increasing promise as an adjunct therapy in rehabilitation following stroke. However, although significant behavioural improvements have been reported in proof-of-principle studies, the underlying mechanisms are poorly understood. The rationale for transcranial direct current stimulation as therapy for stroke is that therapeutic stimulation paradigms increase activity in ipsilesional motor cortical areas, but this has not previously been directly tested for conventional electrode placements. This study was performed to test directly whether increases in ipsilesional cortical activation with transcranial direct current stimulation are associated with behavioural improvements in chronic stroke patients. Patients at least 6 months post-first stroke participated in a behavioural experiment (n = 13) or a functional magnetic resonance imaging experiment (n = 11), each investigating the effects of three stimulation conditions in separate sessions: anodal stimulation to the ipsilesional hemisphere; cathodal stimulation to the contralesional hemisphere; and sham stimulation. Anodal (facilitatory) stimulation to the ipsilesional hemisphere led to significant improvements (5–10%) in response times with the affected hand in both experiments. This improvement was associated with an increase in movement-related cortical activity in the stimulated primary motor cortex and functionally interconnected regions. Cathodal (inhibitory) stimulation to the contralesional hemisphere led to a functional improvement only when compared with sham stimulation. We show for the first time that the significant behavioural improvements produced by anodal stimulation to the ipsilesional hemisphere are associated with a functionally relevant increase in activity within the ipsilesional primary motor cortex in patients with a wide range of disabilities following stroke. PMID:22155982

  3. Dissipative Dynamics of Enzymes

    NASA Astrophysics Data System (ADS)

    Ariyaratne, Amila; Wu, Chenhao; Tseng, Chiao-Yu; Zocchi, Giovanni

    2014-11-01

    We explore enzyme conformational dynamics at sub-Å resolution, specifically, temperature effects. The ensemble-averaged mechanical response of the folded enzyme is viscoelastic in the whole temperature range between the warm and cold denaturation transitions. The dissipation parameter γ of the viscoelastic description decreases by a factor of 2 as the temperature is raised from 10 to 45 °C ; the elastic parameter K shows a similar decrease. Thus, when probed dynamically, the enzyme softens for increasing temperature. Equilibrium mechanical experiments with the DNA spring (and a different enzyme) also show, qualitatively, a small softening for increasing temperature.

  4. Dissipative Dynamics of Enzymes

    NASA Astrophysics Data System (ADS)

    Ariyaratne, Amila; Wu, Chenhao; Tseng, Chiao-Yu; Zocchi, Giovanni; Zocchi LabMolecular Biophysics Team

    2015-03-01

    We explore enzyme conformational dynamics at sub - Å resolution, specifically temperature effects. The ensemble averaged mechanical response of the folded enzyme is viscoelastic in the whole temperature range between the warm and cold denaturation transitions. The dissipation parameter γ of the viscoelastic description decreases by a factor 2 as the temperature is raised from 10 C to 45 C; the elastic parameter K shows a similar decrease. Thus when probed dynamically, the enzyme softens for increasing temperature. Equilibrium mechanical experiments with the DNA spring (and a different enzyme) also show, qualitatively, a small softening for increasing temperature.

  5. Dissipative dynamics of enzymes.

    PubMed

    Ariyaratne, Amila; Wu, Chenhao; Tseng, Chiao-Yu; Zocchi, Giovanni

    2014-11-07

    We explore enzyme conformational dynamics at sub-Å resolution, specifically, temperature effects. The ensemble-averaged mechanical response of the folded enzyme is viscoelastic in the whole temperature range between the warm and cold denaturation transitions. The dissipation parameter γ of the viscoelastic description decreases by a factor of 2 as the temperature is raised from 10 to 45 °C; the elastic parameter K shows a similar decrease. Thus, when probed dynamically, the enzyme softens for increasing temperature. Equilibrium mechanical experiments with the DNA spring (and a different enzyme) also show, qualitatively, a small softening for increasing temperature.

  6. Concentrations of the carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in sidestream cigarette smoke increase after release into indoor air: results from unpublished tobacco industry research.

    PubMed

    Schick, Suzaynn F; Glantz, Stanton

    2007-08-01

    Research has shown that the toxicity of sidestream cigarette smoke, the primary constituent of secondhand smoke, increases over time. To find potential mechanisms that would explain the increase in sidestream smoke toxicity over time, we analyzed unpublished research reports from Philip Morris Co. using the internal tobacco industry documents now available at the University of California San Francisco Legacy Tobacco Documents Library and other Web sites. Unpublished research from Philip Morris Tobacco Company shows that 4-(methylnitrosamino)-I-(3-pyridyl)-1-butanone (NNK), a highly carcinogenic tobacco-specific nitrosamine, can form in sidestream cigarette smoke after it has been released into ambient air. In experiments done between 1983 and 1997, Philip Morris scientists measured the concentration of NNK in sidestream smoke in a sealed stainless steel test chamber at initial particle concentrations of 24 mg/m(3) over the course of 6 to 18 h. They repeatedly showed that airborne NNK concentrations in sidestream cigarette smoke can increase by 50% to 200% per hour during the first 6 h after cigarettes are extinguished. Two experiments done in a real office showed that NNK concentrations increase for the first 2 h after cigarettes are extinguished. If NNK formation also occurs in the lower smoke concentrations observed in real smoking environments, these results suggest that nitrosation of nicotine and/or nicotine breakdown products in aging secondhand smoke is a significant contributor to nitrosamine exposure in humans.

  7. In situ NMR spectroscopy of supercapacitors: insight into the charge storage mechanism.

    PubMed

    Wang, Hao; Forse, Alexander C; Griffin, John M; Trease, Nicole M; Trognko, Lorie; Taberna, Pierre-Louis; Simon, Patrice; Grey, Clare P

    2013-12-18

    Electrochemical capacitors, commonly known as supercapacitors, are important energy storage devices with high power capabilities and long cycle lives. Here we report the development and application of in situ nuclear magnetic resonance (NMR) methodologies to study changes at the electrode-electrolyte interface in working devices as they charge and discharge. For a supercapacitor comprising activated carbon electrodes and an organic electrolyte, NMR experiments carried out at different charge states allow quantification of the number of charge storing species and show that there are at least two distinct charge storage regimes. At cell voltages below 0.75 V, electrolyte anions are increasingly desorbed from the carbon micropores at the negative electrode, while at the positive electrode there is little change in the number of anions that are adsorbed as the voltage is increased. However, above a cell voltage of 0.75 V, dramatic increases in the amount of adsorbed anions in the positive electrode are observed while anions continue to be desorbed at the negative electrode. NMR experiments with simultaneous cyclic voltammetry show that supercapacitor charging causes marked changes to the local environments of charge storing species, with periodic changes of their chemical shift observed. NMR calculations on a model carbon fragment show that the addition and removal of electrons from a delocalized system should lead to considerable increases in the nucleus-independent chemical shift of nearby species, in agreement with our experimental observations.

  8. In Situ NMR Spectroscopy of Supercapacitors: Insight into the Charge Storage Mechanism

    PubMed Central

    2013-01-01

    Electrochemical capacitors, commonly known as supercapacitors, are important energy storage devices with high power capabilities and long cycle lives. Here we report the development and application of in situ nuclear magnetic resonance (NMR) methodologies to study changes at the electrode–electrolyte interface in working devices as they charge and discharge. For a supercapacitor comprising activated carbon electrodes and an organic electrolyte, NMR experiments carried out at different charge states allow quantification of the number of charge storing species and show that there are at least two distinct charge storage regimes. At cell voltages below 0.75 V, electrolyte anions are increasingly desorbed from the carbon micropores at the negative electrode, while at the positive electrode there is little change in the number of anions that are adsorbed as the voltage is increased. However, above a cell voltage of 0.75 V, dramatic increases in the amount of adsorbed anions in the positive electrode are observed while anions continue to be desorbed at the negative electrode. NMR experiments with simultaneous cyclic voltammetry show that supercapacitor charging causes marked changes to the local environments of charge storing species, with periodic changes of their chemical shift observed. NMR calculations on a model carbon fragment show that the addition and removal of electrons from a delocalized system should lead to considerable increases in the nucleus-independent chemical shift of nearby species, in agreement with our experimental observations. PMID:24274637

  9. Resident operative experience in general surgery, plastic surgery, and urology 5 years after implementation of the ACGME duty hour policy.

    PubMed

    Simien, Christopher; Holt, Kathleen D; Richter, Thomas H; Whalen, Thomas V; Coburn, Michael; Havlik, Robert J; Miller, Rebecca S

    2010-08-01

    Resident duty hour restrictions were implemented in 2002-2003. This study examines changes in resident surgical experience since these restrictions were put into place. Operative log data for 3 specialties were examined: general surgery, urology, and plastic surgery. The academic year immediately preceding the duty hour restrictions, 2002-2003, was used as a baseline for comparison to subsequent academic years. Operative log data for graduating residents through 2007-2008 were the primary focus of the analysis. Examination of associated variables that may moderate the relationship between fewer duty hours and surgical volume was also included. Plastic surgery showed no changes in operative volume following duty hour restrictions. Operative volume increased in urology programs. General surgery showed a decrease in volume in some operative categories but an increase in others. Specifically the procedures in vascular, plastic, and thoracic areas showed a consistent decrease. There was no increase in the percentage of programs' graduates falling below minimum requirements. Procedures in pancreas, endocrine, and laparoscopic areas demonstrated an increase in volume. Graduates in larger surgical programs performed fewer procedures than graduates in smaller programs; this was not the case for urology or plastic surgery programs. The reduction of duty hours has not resulted in an across the board decrease in operative volume. Factors other than duty hour reforms may be responsible for some of the observed findings.

  10. A nonpathogenic Fusarium oxysporum strain enhances phytoextraction of heavy metals by the hyperaccumulator Sedum alfredii Hance.

    PubMed

    Zhang, Xincheng; Lin, Li; Chen, Mingyue; Zhu, Zhiqiang; Yang, Weidong; Chen, Bao; Yang, Xiaoe; An, Qianli

    2012-08-30

    Low biomass and shallow root systems limit the application of heavy metal phytoextraction by hyperaccumulators. Plant growth-promoting microbes may enhance hyperaccumulators'phytoextraction. A heavy metal-resistant fungus belonged to the Fusarium oxysporum complex was isolated from the Zn/Cd co-hyperaccumulator Sedum alfredii Hance grown in a Pb/Zn mined area. This Fusarium fungus was not pathogenic to plants but promoted host growth. Hydroponic experiments showed that 500 μM Zn(2+) or 50 μM Cd(2+) combined with the fungus increased root length, branches, and surface areas, enhanced nutrient uptake and chlorophyll synthesis, leading to more vigorous hyperaccumulators with greater root systems. Soil experiments showed that the fungus increased root and shoot biomass and S. alfredii-mediated heavy metal availabilities, uptake, translocation or concentrations, and thus increased phytoextraction of Zn (144% and 44%), Cd (139% and 55%), Pb (84% and 85%) and Cu (63% and 77%) from the original Pb/Zn mined soil and a multi-metal contaminated paddy soil. Together, the nonpathogenic Fusarium fungus was able to increase S. alfredii root systems and function, metal availability and accumulation, plant biomass, and thus phytoextraction efficiency. This study showed a great application potential for culturable indigenous fungi other than symbiotic mycorrhizas to enhance the phytoextraction by hyperaccumulators. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Who gets afraid in the MRI-scanner? Neurogenetics of state-anxiety changes during an fMRI experiment.

    PubMed

    Mutschler, Isabella; Wieckhorst, Birgit; Meyer, Andrea H; Schweizer, Tina; Klarhöfer, Markus; Wilhelm, Frank H; Seifritz, Erich; Ball, Tonio

    2014-11-07

    Experiments using functional magnetic resonance imaging (fMRI) play a fundamental role in affective neuroscience. When placed in an MR scanner, some volunteers feel safe and relaxed in this situation, while others experience uneasiness and fear. Little is known about the basis and consequences of such inter-individually different responses to the general experimental fMRI setting. In this study emotional stimuli were presented during fMRI and subjects' state-anxiety was assessed at the onset and end of the experiment while they were within the scanner. We show that Val/Val but neither Met/Met nor Val/Met carriers of the catechol-O-methyltransferase (COMT) Val(158)Met polymorphism-a prime candidate for anxiety vulnerability-became significantly more anxious during the fMRI experiment (N=97 females: 24 Val/Val, 51 Val/Met, and 22 Met/Met). Met carriers demonstrated brain responses with increased stability over time in the right parietal cortex and significantly better cognitive performances likely mediated by lower levels of anxiety. Val/Val, Val/Met and Met/Met did not significantly differ in state-anxiety at the beginning of the experiment. The exposure of a control group (N=56 females) to the same experiment outside the scanner did not cause a significant increase in state-anxiety, suggesting that the increase we observe in the fMRI experiment may be specific to the fMRI setting. Our findings reveal that genetics may play an important role in shaping inter-individual different emotional, cognitive and neuronal responses during fMRI experiments. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. High glucose condition increases NADPH oxidase activity in endothelial microparticles that promote vascular inflammation.

    PubMed

    Jansen, Felix; Yang, Xiaoyan; Franklin, Bernardo S; Hoelscher, Marion; Schmitz, Theresa; Bedorf, Jörg; Nickenig, Georg; Werner, Nikos

    2013-04-01

    Diabetes is a major risk factor for cardiovascular diseases. Circulating endothelial microparticles (EMP) are increased in diabetic patients, but their potential contribution in atherogenesis is unclear. We sought to determine the role of EMP derived under high glucose conditions in the development of atherosclerosis. EMP were generated from human coronary endothelial cells (HCAEC) exposed to high glucose concentrations in order to mimic diabetic conditions. These EMP were defined as 'injured' EMP (iEMP) and their effects were compared with EMP generated from 'healthy' untreated HCAEC. iEMP injection significantly impaired endothelial function in ApoE(-/-) mice compared with EMP and vehicle treatment. Immunofluorescent experiments showed increased macrophage infiltration and adhesion protein expression in atherosclerotic lesions of iEMP-treated ApoE(-/-) mice compared with controls. To further investigate the underlying mechanism of iEMP-induced vascular inflammation, additional in vitro experiments were performed. iEMP, but not EMP, induced activation of HCAEC in a time- and dose-dependent manner and increased monocyte adhesion. Further experiments demonstrated that iEMP induced activation of HCAEC by phosphorylation of p38 into its biologically active form phospho-p38. Inhibition of p38 activation abrogated iEMP-dependent induction of adhesion proteins and monocyte adhesion on HCAEC. Moreover, we could demonstrate that iEMP show increased NADPH oxidase activity and contain significantly higher level of reactive oxygen species (ROS) than EMP. iEMP triggered ROS production in HCAEC and thereby activate p38 in an ROS-dependent manner. High glucose condition increases NADPH oxidase activity in endothelial microparticles that amplify endothelial inflammation and impair endothelial function by promoting activation of the endothelium. These findings provide new insights into the pathogenesis of diabetes-associated atherosclerosis.

  13. Response of the larger protozooplankton to an iron-induced phytoplankton bloom in the Polar Frontal Zone of the Southern Ocean (EisenEx)

    NASA Astrophysics Data System (ADS)

    Henjes, Joachim; Assmy, Philipp; Klaas, Christine; Smetacek, Victor

    2007-05-01

    The responses of larger (>50 μm in diameter) protozooplankton groups to a phytoplankton bloom induced by in situ iron fertilization (EisenEx) in the Polar Frontal Zone (PFZ) of the Southern Ocean in austral spring are presented. During the 21 days of the experiment, samples were collected from seven discrete depths in the upper 150 m inside and outside the fertilized patch for the enumeration of acantharia, foraminifera, radiolaria, heliozoa, tintinnid ciliates and aplastidic thecate dinoflagellates. Inside the patch, acantharian numbers increased twofold, but only negligibly in surrounding waters. This finding is of major interest, since acantharia are suggested to be involved in the formation of barite (BaSO 4), a palaeoindicator of both ancient and modern high-productivity regimes. Foraminifera increased significantly in abundance inside and outside the fertilized patch. However, the marked increase of juveniles after a full-moon event suggests a lunar periodicity in the reproduction cycle of some foraminiferan species rather than a reproductive response to enhanced food availability. In contrast, adult radiolaria showed no clear trend during the experiment, but juveniles increased threefold, indicating elevated reproduction. Aplastidic thecate dinoflagellates almost doubled in numbers and biomass but also increased outside the patch. Tintinnid numbers decreased twofold, although biomass remained constant because of a shift in the size spectrum. Empty tintinnid loricae, however, increased by a factor of two, indicating that grazing pressure on this group mainly by copepods, intensified during EisenEx. The results show that iron-fertilization experiments can shed light on the biology and the role of these larger protists in pelagic ecosystem, which will improve their use as proxies in paleoceanography.

  14. People living on the street from the health point of view.

    PubMed

    Hino, Paula; Santos, Jaqueline de Oliveira; Rosa, Anderson da Silva

    2018-01-01

    To know the Brazilian scientific production of the last ten years (2007 to 2016) about people who experience street situations under the health gaze. Integrative literature review using the descriptors: street people, health policy and public health. We analyzed 21 articles available in the Virtual Health Library. Four categories of analysis emerged. There was an increase in the frequency of published work on the subject, showing that the experience of living on the street makes people vulnerable to various diseases and health problems and, in addition, increases the difficulties of access to health services. There was an increase in the discussion of this topic due to the increase in the number of published studies. Despite the existence of public health policies directed to this social group, much still needs to be done to guarantee the health of this population.

  15. Baroreceptors mask sympathetic responses to high intraocular pressure in dogs.

    PubMed

    Yahagi, Toru; Koyama, Shozo; Osaka, Kazumasa; Koyama, Haruhide

    2008-05-30

    These experiments were designed to investigate whether increasing intraocular pressure (IOP) in anesthetized dogs produces differential control of sympathetic nerve activities to various organs (heart, kidney, liver, and spleen) and if these sympathetic responses are modified by baroreceptors. We performed simultaneous multi-recordings of cardiac, renal, hepatic and splenic sympathetic nerve activities (CNA, RNA, HNA and SpNA, respectively) during 2 min of increasing IOP to a mean pressure of 30 mmHg. After increasing IOP in dogs with the intact baroreceptors, all of measured nerve activities did not change significantly throughout the experiment. In dogs with denervation of baroreceptors (cervical vagotomy with denervation of the carotid sinus and aortic nerves), only RNA and CNA showed significant increases in response to the increased IOP. However, time course changes in HNA and SpNA did not show any significant differences as compared with the baseline or that of the control group. These results indicate that systemic sympathetic nerve responses to increasing IOP are masked by systemic baroreceptors. As animals were denervated of their systemic baroreceptors, the unidirectional sympathoexcitatory responses to increased IOP were observed on CNA and RNA, but not on HNA and SpNA. These sympathetic outflow, when systemic baroreceptors are impaired as observed in old age, may play an important role in management of glaucoma attack with the use of adrenolytic drugs.

  16. Confinement improvement in the high poloidal beta regime on DIII-D and application to steady-state H-mode on EAST

    NASA Astrophysics Data System (ADS)

    Ding, S.; Garofalo, A. M.; Qian, J.; Cui, L.; McClenaghan, J. T.; Pan, C.; Chen, J.; Zhai, X.; McKee, G.; Ren, Q.; Gong, X.; Holcomb, C. T.; Guo, W.; Lao, L.; Ferron, J.; Hyatt, A.; Staebler, G.; Solomon, W.; Du, H.; Zang, Q.; Huang, J.; Wan, B.

    2017-05-01

    Systematic experimental and modeling investigations on DIII-D show attractive transport properties of fully non-inductive high βp plasmas. Experiments on DIII-D show that the large-radius internal transport barrier (ITB), a key feature providing excellent confinement in the high βp regime, is maintained when the scenario is extended from q95 ˜ 12 to 7 and from rapid to near-zero toroidal rotation. The robustness of confinement versus rotation was predicted by gyrofluid modeling showing dominant neoclassical ion energy transport even without the E × B shear effect. The physics mechanism of turbulence suppression, we found, is the Shafranov shift, which is essential and sets a βp threshold for large-radius ITB formation in the high βp scenario on DIII-D. This is confirmed by two different parameter-scan experiments, one for a βN scan and the other for a q95 scan. They both give the same βp threshold at 1.9 in the experiment. The experimental trend of increasing thermal transport with decreasing βp is consistent with transport modeling. The progress toward the high βp scenario on Experimental Advanced Superconducting Tokamak (EAST) is reported. The very first step of extending the high βp scenario on DIII-D to long pulse on EAST is to establish a long pulse H-mode with ITB on EAST. This paper shows the first 61 s fully non-inductive H-mode with stationary ITB feature and actively cooled ITER-like tungsten divertor in the very recent EAST experiment. The successful use of lower hybrid wave as a key tool to optimize the current profile in the EAST experiment is also introduced. Results show that as the electron density is increased, the fully non-inductive current profile broadens on EAST. The improved understanding and modeling capability are also used to develop advanced scenarios for the China Fusion Engineering Test Reactor. Overall, these results provide encouragement that the high βp regime can be extended to a lower safety factor and very low rotation, providing a potential path to high performance steady state operation in future devices.

  17. Proline-containing dipeptide GVS-111 retains nootropic activity after oral administration.

    PubMed

    Ostrovskaya, R U; Mirsoev, T K; Romanova, G A; Gudasheva, T A; Kravchenko, E V; Trofimov, C C; Voronina, T A; Seredenin, S B

    2001-10-01

    Experiments on rats trained passive avoidance task showed that N-phenyl-acetyl-L-prolyl-glycyl ethyl ester, peptide analog of piracetam (GVS-111, Noopept) after oral administration retained antiamnesic activity previously observed after its parenteral administration. Effective doses were 0.5-10 mg/kg. Experiments on a specially-developed model of active avoidance (massive one-session learning schedule) showed that GVS-111 stimulated one-session learning after single administration, while after repeated administration it increased the number of successful learners among those animals who failed after initial training. In this respect, GVS-111 principally differs from its main metabolite cycloprolylglycine and standard nootropic piracetam.

  18. Long term fault system reorganization of convergent and strike-slip systems

    NASA Astrophysics Data System (ADS)

    Cooke, M. L.; McBeck, J.; Hatem, A. E.; Toeneboehn, K.; Beyer, J. L.

    2017-12-01

    Laboratory and numerical experiments representing deformation over many earthquake cycles demonstrate that fault evolution includes episodes of fault reorganization that optimize work on the fault system. Consequently, the mechanical and kinematic efficiencies of fault systems do not increase monotonically through their evolution. New fault configurations can optimize the external work required to accommodate deformation, suggesting that changes in system efficiency can drive fault reorganization. Laboratory evidence and numerical results show that fault reorganization within accretion, strike-slip and oblique convergent systems is associated with increasing efficiency due to increased fault slip (frictional work and seismic energy) and commensurate decreased off-fault deformation (internal work and work against gravity). Between episodes of fault reorganization, fault systems may become less efficient as they produce increasing off fault deformation. For example, laboratory and numerical experiments show that the interference and interaction between different fault segments may increase local internal work or that increasing convergence can increase work against gravity produced by a fault system. This accumulation of work triggers fault reorganization as stored work provides the energy required to grow new faults that reorganize the system to a more efficient configuration. The results of laboratory and numerical experiments reveal that we should expect crustal fault systems to reorganize following periods of increasing inefficiency, even in the absence of changes to the tectonic regime. In other words, fault reorganization doesn't require a change in tectonic loading. The time frame of fault reorganization depends on fault system configuration, strain rate and processes that relax stresses within the crust. For example, stress relaxation may keep pace with stress accumulation, which would limit the increase in the internal work and gravitational work so that irregularities can persist along active fault systems without reorganization of the fault system. Consequently, steady state behavior, for example with constant fault slip rates, may arise either in systems with high degree of stress-relaxation or occur only within the intervals between episodes of fault reorganization.

  19. The Predicting Model of E-commerce Site Based on the Ideas of Curve Fitting

    NASA Astrophysics Data System (ADS)

    Tao, Zhang; Li, Zhang; Dingjun, Chen

    On the basis of the idea of the second multiplication curve fitting, the number and scale of Chinese E-commerce site is analyzed. A preventing increase model is introduced in this paper, and the model parameters are solved by the software of Matlab. The validity of the preventing increase model is confirmed though the numerical experiment. The experimental results show that the precision of preventing increase model is ideal.

  20. Bubble-Induced Color Doppler Feedback for Histotripsy Tissue Fractionation.

    PubMed

    Miller, Ryan M; Zhang, Xi; Maxwell, Adam D; Cain, Charles A; Xu, Zhen

    2016-03-01

    Histotripsy therapy produces cavitating bubble clouds to increasingly fractionate and eventually liquefy tissue using high-intensity ultrasound pulses. Following cavitation generated by each pulse, coherent motion of the cavitation residual nuclei can be detected using metrics formed from ultrasound color Doppler acquisitions. In this paper, three experiments were performed to investigate the characteristics of this motion as real-time feedback on histotripsy tissue fractionation. In the first experiment, bubble-induced color Doppler (BCD) and particle image velocimetry (PIV) analysis monitored the residual cavitation nuclei in the treatment region in an agarose tissue phantom treated with two-cycle histotripsy pulses at [Formula: see text] using a 500-kHz transducer. Both BCD and PIV results showed brief chaotic motion of the residual nuclei followed by coherent motion first moving away from the transducer and then rebounding back. Velocity measurements from both PIV and BCD agreed well, showing a monotonic increase in rebound time up to a saturation point for increased therapy dose. In a second experiment, a thin layer of red blood cells (RBC) was added to the phantom to allow quantification of the fractionation of the RBC layer to compare with BCD metrics. A strong linear correlation was observed between the fractionation level and the time to BCD peak rebound velocity over histotripsy treatment. Finally, the correlation between BCD feedback and histotripsy tissue fractionation was validated in ex vivo porcine liver evaluated histologically. BCD metrics showed strong linear correlation with fractionation progression, suggesting that BCD provides useful quantitative real-time feedback on histotripsy treatment progression.

  1. Bubble-induced Color Doppler Feedback for Histotripsy Tissue Fractionation

    PubMed Central

    Miller, Ryan M.; Zhang, Xi; Maxwell, Adam; Cain, Charles; Xu, Zhen

    2016-01-01

    Histotripsy therapy produces cavitating bubble clouds to increasingly fractionate and eventually liquefy tissue using high intensity ultrasound pulses. Following cavitation generated by each pulse, coherent motion of the cavitation residual nuclei can be detected using metrics formed from ultrasound color Doppler acquisitions. In this paper, three experiments were performed to investigate the characteristics of this motion as real-time feedback on histotripsy tissue fractionation. In the first experiment, bubble-induced color Doppler (BCD) and particle image velocimetry (PIV) analysis monitored the residual cavitation nuclei in the treatment region in an agarose tissue phantom treated with 2-cycle histotripsy pulses at > 30 MPa using a 500 kHz transducer. Both BCD and PIV results showed brief chaotic motion of the residual nuclei followed by coherent motion first moving away from the transducer and then rebounding back. Velocity measurements from both PIV and BCD agreed well, showing a monotonic increase in rebound time up to a saturation point for increased therapy dose. In a second experiment, a thin layer of red blood cells (RBC) was added to the phantom to allow quantification of the fractionation of the RBC layer to compare with BCD metrics. A strong linear correlation was observed between the fractionation level and the time to BCD peak rebound velocity over histotripsy treatment. Finally, the correlation between BCD feedback and histotripsy tissue fractionation was validated in ex vivo porcine liver evaluated histologically. BCD metrics showed strong linear correlation with fractionation progression, suggesting that BCD provides useful quantitative real-time feedback on histotripsy treatment progression. PMID:26863659

  2. Phosphorus vertical migration in aquic brown soil and light chernozem under different phosphorous application rate: a soil column leaching experiment.

    PubMed

    Zhao, Muqiu; Chen, Xin; Shi, Yi; Zhou, Quanlai; Lu, Caiyan

    2009-01-01

    A soil column leaching experiment was conducted to study the vertical migration of phosphorus in aquic brown soil and light chernozem under different phosphorus fertilization rates. The results showed that total dissolved phosphorus concentration in the leachates from the two soils was nearly the same, but dissolved inorganic phosphorus concentration was obviously different. In all fertilization treatments, aquic brown soil had a higher content of phosphorus in calcium chloride extracts compared with light chernozem. But Olsen phosphorus content was higher at the soil depth beneath 0-20 cm, and increased with increasing phosphorus application rate.

  3. Simulation and measurement of total ionizing dose radiation induced image lag increase in pinned photodiode CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Liu, Jing; Chen, Wei; Wang, Zujun; Xue, Yuanyuan; Yao, Zhibin; He, Baoping; Ma, Wuying; Jin, Junshan; Sheng, Jiangkun; Dong, Guantao

    2017-06-01

    This paper presents an investigation of total ionizing dose (TID) induced image lag sources in pinned photodiodes (PPD) CMOS image sensors based on radiation experiments and TCAD simulation. The radiation experiments have been carried out at the Cobalt -60 gamma-ray source. The experimental results show the image lag degradation is more and more serious with increasing TID. Combining with the TCAD simulation results, we can confirm that the junction of PPD and transfer gate (TG) is an important region forming image lag during irradiation. These simulations demonstrate that TID can generate a potential pocket leading to incomplete transfer.

  4. Interfacial Bubble Deformations

    NASA Astrophysics Data System (ADS)

    Seymour, Brian; Shabane, Parvis; Cypull, Olivia; Cheng, Shengfeng; Feitosa, Klebert

    Soap bubbles floating at an air-water experience deformations as a result of surface tension and hydrostatic forces. In this experiment, we investigate the nature of such deformations by taking cross-sectional images of bubbles of different volumes. The results show that as their volume increases, bubbles transition from spherical to hemispherical shape. The deformation of the interface also changes with bubble volume with the capillary rise converging to the capillary length as volume increases. The profile of the top and bottom of the bubble and the capillary rise are completely determined by the volume and pressure differences. James Madison University Department of Physics and Astronomy, 4VA Consortium, Research Corporation for Advancement of Science.

  5. The impact of sensorimotor experience on affective evaluation of dance

    PubMed Central

    Kirsch, Louise P.; Drommelschmidt, Kim A.; Cross, Emily S.

    2013-01-01

    Past research demonstrates that we are more likely to positively evaluate a stimulus if we have had previous experience with that stimulus. This has been shown for judgment of faces, architecture, artworks and body movements. In contrast, other evidence suggests that this relationship can also work in the inverse direction, at least in the domain of watching dance. Specifically, it has been shown that in certain contexts, people derive greater pleasure from watching unfamiliar movements they would not be able to physically reproduce compared to simpler, familiar actions they could physically reproduce. It remains unknown, however, how different kinds of experience with complex actions, such as dance, might change observers' affective judgments of these movements. Our aim was to clarify the relationship between experience and affective evaluation of whole body movements. In a between-subjects design, participants received either physical dance training with a video game system, visual and auditory experience or auditory experience only. Participants' aesthetic preferences for dance stimuli were measured before and after the training sessions. Results show that participants from the physical training group not only improved their physical performance of the dance sequences, but also reported higher enjoyment and interest in the stimuli after training. This suggests that physically learning particular movements leads to greater enjoyment while observing them. These effects are not simply due to increased familiarity with audio or visual elements of the stimuli, as the other two training groups showed no increase in aesthetic ratings post-training. We suggest these results support an embodied simulation account of aesthetics, and discuss how the present findings contribute to a better understanding of the shaping of preferences by sensorimotor experience. PMID:24027511

  6. Deposition and transport of Pseudomonas aeruginosa in porous media: lab-scale experiments and model analysis.

    PubMed

    Kwon, Kyu-Sang; Kim, Song-Bae; Choi, Nag-Choul; Kim, Dong-Ju; Lee, Soonjae; Lee, Sang-Hyup; Choi, Jae-Woo

    2013-01-01

    In this study, the deposition and transport of Pseudomonas aeruginosa on sandy porous materials have been investigated under static and dynamic flow conditions. For the static experiments, both equilibrium and kinetic batch tests were performed at a 1:3 and 3:1 soil:solution ratio. The batch data were analysed to quantify the deposition parameters under static conditions. Column tests were performed for dynamic flow experiments with KCl solution and bacteria suspended in (1) deionized water, (2) mineral salt medium (MSM) and (3) surfactant + MSM. The equilibrium distribution coefficient (K(d)) was larger at a 1:3 (2.43 mL g(-1)) than that at a 3:1 (0.28 mL g(-1)) soil:solution ratio. Kinetic batch experiments showed that the reversible deposition rate coefficient (k(att)) and the release rate coefficient (k(det)) at a soil:solution ratio of 3:1 were larger than those at a 1:3 ratio. Column experiments showed that an increase in ionic strength resulted in a decrease in peak concentration of bacteria, mass recovery and tailing of the bacterial breakthrough curve (BTC) and that the presence of surfactant enhanced the movement of bacteria through quartz sand, giving increased mass recovery and tailing. Deposition parameters under dynamic condition were determined by fitting BTCs to four different transport models, (1) kinetic reversible, (2) two-site, (3) kinetic irreversible and (4) kinetic reversible and irreversible models. Among these models, Model 4 was more suitable than the others since it includes the irreversible sorption term directly related to the mass loss of bacteria observed in the column experiment. Applicability of the parameters obtained from the batch experiments to simulate the column breakthrough data is evaluated.

  7. Cognition and balance control: does processing of explicit contextual cues of impending perturbations modulate automatic postural responses?

    PubMed

    Coelho, Daniel Boari; Teixeira, Luis Augusto

    2017-08-01

    Processing of predictive contextual cues of an impending perturbation is thought to induce adaptive postural responses. Cueing in previous research has been provided through repeated perturbations with a constant foreperiod. This experimental strategy confounds explicit predictive cueing with adaptation and non-specific properties of temporal cueing. Two experiments were performed to assess those factors separately. To perturb upright balance, the base of support was suddenly displaced backwards in three amplitudes: 5, 10 and 15 cm. In Experiment 1, we tested the effect of cueing the amplitude of the impending postural perturbation by means of visual signals, and the effect of adaptation to repeated exposures by comparing block versus random sequences of perturbation. In Experiment 2, we evaluated separately the effects of cueing the characteristics of an impending balance perturbation and cueing the timing of perturbation onset. Results from Experiment 1 showed that the block sequence of perturbations led to increased stability of automatic postural responses, and modulation of magnitude and onset latency of muscular responses. Results from Experiment 2 showed that only the condition cueing timing of platform translation onset led to increased balance stability and modulation of onset latency of muscular responses. Conversely, cueing platform displacement amplitude failed to induce any effects on automatic postural responses in both experiments. Our findings support the interpretation of improved postural responses via optimized sensorimotor processes, at the same time that cast doubt on the notion that cognitive processing of explicit contextual cues advancing the magnitude of an impending perturbation can preset adaptive postural responses.

  8. Modification of fecundity and fertility during oogenesis by. gamma. radiation and/or ozone with a cytological analysis in the ectoparasitic wasp, Habrobracon juglandis (Ashmead)

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

    Ofuoku, E.E.

    1984-01-01

    In Experiment I, adult female wasps were exposed to ozone for 0, 2, 4, 6, 8, 10, 12, 16, 24, and 27 h. The results indicated that the 27 h of ozone exposure produced 100% lethality on the first day. Exposures below 27 h progressively decreased life span with increasing length of exposure. In Experiment II A, adult virgin Habrobracon females were exposed to ozone for 0, 2, 4, 6, 8, 10, 12, 16, and 24 h to determine the effects of ozone on fecundity (egg laying ability) and fertility (egg hatching ability). The results showed that ozone significantly decreasedmore » fecundity and fertility in all meiotic stages except metaphase I. In Experiment II B, adult virgin Habrobracon females were exposed to Co-60 ..gamma.. radiation. All treated wasps showed significant progressive decreases in fecundity and fertility with increases in radiation dose. In Experiment II C, adult virgin Habrobracon females were exposed to Co-60 ..gamma.. radiation, to ozone, or to combinations thereof to determine the effects of these insults on fecundity and fertility. Together or singly ozone and radiation reduced fecundity and fertility. In Experiment III, adult virgin Habrobracon females were exposed to the conditions of Experiment II C to correlate by cytological examination of the ovarioles the effects of ionizing radiation and/or ozone on the germ cells at specific meiotic stages. Results obtained from the cytological study explain the fecundity and fertility observations.« less

  9. Servo-control of water and sodium homeostasis during renal clearance measurements in conscious rats.

    PubMed

    Thomsen, Klaus; Shirley, David G

    2007-01-01

    Servo-controlled fluid and sodium replacement during clearance studies is used in order to prevent loss of body fluid and sodium following diuretic/natriuretic procedures. However, even under control conditions, the use of this technique is sometimes associated with increases in proximal tubular fluid output (assessed by lithium clearance) and excretion rates. The present study examined the reason for these increases. The first series of experiments showed that one cause is volume overloading. This can occur if the servo system is activated from the start, i.e., during the establishment of a suitably high urine flow rate by constant infusion of hypotonic glucose solution. The second series of experiments showed that replacement of blood samples with donor blood can also lead to increases in fractional lithium excretion and accompanying increases in water and sodium excretion, a problem not seen when blood samples are replaced with the animal's own red blood cells resuspended in isotonic saline. When these pitfalls are avoided, servo-controlled sodium and fluid replacement is a reliable technique that makes it possible to study the effects of natriuretic and/or diuretic stimuli without interference from unwanted changes in extracellular volume. 2007 S. Karger AG, Basel

  10. The brain of opera singers: experience-dependent changes in functional activation.

    PubMed

    Kleber, B; Veit, R; Birbaumer, N; Gruzelier, J; Lotze, M

    2010-05-01

    Several studies have shown that motor-skill training over extended time periods results in reorganization of neural networks and changes in brain morphology. Yet, little is known about training-induced adaptive changes in the vocal system, which is largely subserved by intrinsic reflex mechanisms. We investigated highly accomplished opera singers, conservatory level vocal students, and laymen during overt singing of an Italian aria in a neuroimaging experiment. We provide the first evidence that the training of vocal skills is accompanied by increased functional activation of bilateral primary somatosensory cortex representing articulators and larynx. Opera singers showed additional activation in right primary sensorimotor cortex. Further training-related activation comprised the inferior parietal lobe and bilateral dorsolateral prefrontal cortex. At the subcortical level, expert singers showed increased activation in the basal ganglia, the thalamus, and the cerebellum. A regression analysis of functional activation with accumulated singing practice confirmed that vocal skills training correlates with increased activity of a cortical network for enhanced kinesthetic motor control and sensorimotor guidance together with increased involvement of implicit motor memory areas at the subcortical and cerebellar level. Our findings may have ramifications for both voice rehabilitation and deliberate practice of other implicit motor skills that require interoception.

  11. Inhibition effect of fatty amides with secondary compound on carbon steel corrosion in hydrodynamic condition

    NASA Astrophysics Data System (ADS)

    Ibrahim, I. M.; Jai, J.; Daud, M.; Hashim, Md A.

    2018-03-01

    The inhibition effect demonstrates an increase in the inhibition performance in presence of a secondary compound in the inhibited solution. This study introduces fatty amides as corrosion inhibitor and oxygen scavenger, namely, sodium sulphite as a secondary compound. The main objective is to determine the synergistic inhibition effect of a system by using fatty amides together with sodium sulphite in hydrodynamic condition. The synergistic inhibition of fatty amides and sodium sulphite on corrosion of carbon steel in 3.5 wt% sodium chloride solution had been studied using linear polarization resistance method and scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDX). Electrochemical measurement was carried out using rotating cylinder electrode at different flow regimes (static, laminar, transition and turbulent). Linear polarization resistance experiments showed the changes in polarization resistance when the rotation speed increased. It found that, by addition of fatty amides together with sodium sulphite in test solution, the inhibition efficiency increased when rotation speed increased. The results collected from LPR experiment correlated with results from SEM-EDX. The results showed inhibition efficiency of system was enhanced when fatty amides and oxygen scavengers were present together.

  12. Evaluation of transcutol as a clonazepam transdermal permeation enhancer from hydrophilic gel formulations.

    PubMed

    Mura, P; Faucci, M T; Bramanti, G; Corti, P

    2000-02-01

    The influence of diethyleneglycol monoethyl ether (transcutol), alone or in combination with propylene glycol, on clonazepam permeation through an artificial membrane and excised rabbit ear skin from Carbopol hydrogels was investigated. Drug kinetic permeation parameters were determined for both series of experiments and compared. Rheological characteristics, drug solubility and membrane/vehicle partition coefficient for each gel formulation were also determined, and their role in the formulation performance was investigated. Both series of experiments showed an increase of drug permeation as a function of transcutol content in the formulation. The combination of transcutol and propylene glycol resulted in a synergistic enhancement of clonazepam flux. A different trend was found in experiments with gels containing mixtures of the two enhancers, where an increase (in the case of artificial membrane) or a decrease (in the case of rabbit ear skin) of drug permeation was found by increasing the transcutol/propylene glycol ratio in the mixture. Such a result is explained on the basis of the particular mechanism of action demonstrated for transcutol which associates the increase of drug solubility to the potent effect of a depot in the skin.

  13. Do lab-derived distribution coefficient values of pesticides match distribution coefficient values determined from column and field-scale experiments? A critical analysis of relevant literature.

    PubMed

    Vereecken, H; Vanderborght, J; Kasteel, R; Spiteller, M; Schäffer, A; Close, M

    2011-01-01

    In this study, we analyzed sorption parameters for pesticides that were derived from batch and column or batch and field experiments. The batch experiments analyzed in this study were run with the same pesticide and soil as in the column and field experiments. We analyzed the relationship between the pore water velocity of the column and field experiments, solute residence times, and sorption parameters, such as the organic carbon normalized distribution coefficient ( ) and the mass exchange coefficient in kinetic models, as well as the predictability of sorption parameters from basic soil properties. The batch/column analysis included 38 studies with a total of 139 observations. The batch/field analysis included five studies, resulting in a dataset of 24 observations. For the batch/column data, power law relationships between pore water velocity, residence time, and sorption constants were derived. The unexplained variability in these equations was reduced, taking into account the saturation status and the packing status (disturbed-undisturbed) of the soil sample. A new regression equation was derived that allows estimating the values derived from column experiments using organic matter and bulk density with an value of 0.56. Regression analysis of the batch/column data showed that the relationship between batch- and column-derived values depends on the saturation status and packing of the soil column. Analysis of the batch/field data showed that as the batch-derived value becomes larger, field-derived values tend to be lower than the corresponding batch-derived values, and vice versa. The present dataset also showed that the variability in the ratio of batch- to column-derived value increases with increasing pore water velocity, with a maximum value approaching 3.5. American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.

  14. When seeing outweighs feeling: a role for prefrontal cortex in passive control of negative affect in blindsight.

    PubMed

    Anders, Silke; Eippert, Falk; Wiens, Stefan; Birbaumer, Niels; Lotze, Martin; Wildgruber, Dirk

    2009-11-01

    Affective neuroscience has been strongly influenced by the view that a 'feeling' is the perception of somatic changes and has consequently often neglected the neural mechanisms that underlie the integration of somatic and other information in affective experience. Here, we investigate affective processing by means of functional magnetic resonance imaging in nine cortically blind patients. In these patients, unilateral postgeniculate lesions prevent primary cortical visual processing in part of the visual field which, as a result, becomes subjectively blind. Residual subcortical processing of visual information, however, is assumed to occur in the entire visual field. As we have reported earlier, these patients show significant startle reflex potentiation when a threat-related visual stimulus is shown in their blind visual field. Critically, this was associated with an increase of brain activity in somatosensory-related areas, and an increase in experienced negative affect. Here, we investigated the patients' response when the visual stimulus was shown in the sighted visual field, that is, when it was visible and cortically processed. Despite the fact that startle reflex potentiation was similar in the blind and sighted visual field, patients reported significantly less negative affect during stimulation of the sighted visual field. In other words, when the visual stimulus was visible and received full cortical processing, the patients' phenomenal experience of affect did not closely reflect somatic changes. This decoupling of phenomenal affective experience and somatic changes was associated with an increase of activity in the left ventrolateral prefrontal cortex and a decrease of affect-related somatosensory activity. Moreover, patients who showed stronger left ventrolateral prefrontal cortex activity tended to show a stronger decrease of affect-related somatosensory activity. Our findings show that similar affective somatic changes can be associated with different phenomenal experiences of affect, depending on the depth of cortical processing. They are in line with a model in which the left ventrolateral prefrontal cortex is a relay station that integrates information about subcortically triggered somatic responses and information resulting from in-depth cortical stimulus processing. Tentatively, we suggest that the observed decoupling of somatic responses and experienced affect, and the reduction of negative phenomenal experience, can be explained by a left ventrolateral prefrontal cortex-mediated inhibition of affect-related somatosensory activity.

  15. When seeing outweighs feeling: a role for prefrontal cortex in passive control of negative affect in blindsight

    PubMed Central

    Eippert, Falk; Wiens, Stefan; Birbaumer, Niels; Lotze, Martin; Wildgruber, Dirk

    2009-01-01

    Affective neuroscience has been strongly influenced by the view that a ‘feeling’ is the perception of somatic changes and has consequently often neglected the neural mechanisms that underlie the integration of somatic and other information in affective experience. Here, we investigate affective processing by means of functional magnetic resonance imaging in nine cortically blind patients. In these patients, unilateral postgeniculate lesions prevent primary cortical visual processing in part of the visual field which, as a result, becomes subjectively blind. Residual subcortical processing of visual information, however, is assumed to occur in the entire visual field. As we have reported earlier, these patients show significant startle reflex potentiation when a threat-related visual stimulus is shown in their blind visual field. Critically, this was associated with an increase of brain activity in somatosensory-related areas, and an increase in experienced negative affect. Here, we investigated the patients’ response when the visual stimulus was shown in the sighted visual field, that is, when it was visible and cortically processed. Despite the fact that startle reflex potentiation was similar in the blind and sighted visual field, patients reported significantly less negative affect during stimulation of the sighted visual field. In other words, when the visual stimulus was visible and received full cortical processing, the patients’ phenomenal experience of affect did not closely reflect somatic changes. This decoupling of phenomenal affective experience and somatic changes was associated with an increase of activity in the left ventrolateral prefrontal cortex and a decrease of affect-related somatosensory activity. Moreover, patients who showed stronger left ventrolateral prefrontal cortex activity tended to show a stronger decrease of affect-related somatosensory activity. Our findings show that similar affective somatic changes can be associated with different phenomenal experiences of affect, depending on the depth of cortical processing. They are in line with a model in which the left ventrolateral prefrontal cortex is a relay station that integrates information about subcortically triggered somatic responses and information resulting from in-depth cortical stimulus processing. Tentatively, we suggest that the observed decoupling of somatic responses and experienced affect, and the reduction of negative phenomenal experience, can be explained by a left ventrolateral prefrontal cortex-mediated inhibition of affect-related somatosensory activity. PMID:19767414

  16. Behavior of Epoxy-Coated Textured Reinforcing Bars

    DOT National Transportation Integrated Search

    2018-04-01

    Cracking in bridge decks is a common but difficult problem to control. Both research and experience show that the use of epoxy-coated reinforcement, which is mandated by most state departments of transportation (DOTs) for bridge decks, increases c...

  17. A Discordant Monozygotic Twin Design Shows Blunted Cortisol Reactivity Among Bullied Children

    PubMed Central

    Ouellet-Morin, Isabelle; Danese, Andrea; Bowes, Lucy; Shakoor, Sania; Ambler, Antony; Pariante, Carmine M.; Papadopoulos, Andrew S.; Caspi, Avshalom; Moffitt, Terrie E.; Arseneault, Louise

    2013-01-01

    Objective Childhood adverse experiences are known to engender persistent changes in stress-related systems and brain structures involved in mood, cognition, and behavior in animal models. Uncertainty remains about the causal effect of early stressful experiences on physiological response to stress in human beings, as the impact of these experiences has rarely been investigated while controlling for both genetic and shared environmental influences. Method We tested whether bullying victimization, a repeated adverse experience in childhood, influences cortisol responses to a psychosocial stress test (PST) using a discordant monozygotic (MZ) twin design. Thirty pairs (43.3% males) of 12-year-old MZ twins discordant for bullying victimization were identified in the Environmental Risk (E-Risk) Longitudinal Twin Study, a nationally representative 1994–1995 cohort of families with twins. Results Bullied and nonbullied MZ twins showed distinct patterns of cortisol secretion after the PST. Specifically, bullied twins exhibited a blunted cortisol response compared with their nonbullied MZ co-twins, who showed the expected increase. This difference in cortisol response to stress could not be attributed to children's genetic makeup, their familial environments, pre-existing and concomitant individual factors, or the perception of stress and emotional response to the PST. Conclusion Results from this natural experiment provide support for a causal effect of adverse childhood experiences on the neuroendocrine response to stress. PMID:21621141

  18. A Simon effect for depth in three-dimensional displays.

    PubMed

    Rigon, Jessica; Massaccesi, Stefano; Umiltà, Carlo

    2011-01-01

    We investigated whether the Simon effect occurs for the depth dimension in a 3-dimensional display. In Experiment 1, participants executed discriminative responses to 2 stimuli, a cross and a sphere, both 3-dimensional, which were perceived to be located near or far with respect to the participant's body. The response keys were located near and far along the participant's midline. Apparent stimulus spatial location (near or far) was irrelevant to the task. Results showed a depth Simon effect, attributable to the apparent stimulus spatial location. Experiment 2 replicated Experiment 1 with a different procedure. The 2 stimuli, a triangle and a rectangle, were 2-dimensional and were perceived as being located near or far from the participant's midline; the response keys were located near and far along the participant's midline. Results showed again the depth Simon effect. Experiment 3 was a control condition in which the 2 stimuli, drawings of a lamp and of a chair, had the same size, regardless of whether they appeared to be near or far. The depth Simon effect was replicated. A distribution analysis on data of Experiment 3 showed that the Simon effect increased as reaction times became longer. In Experiment 4, the position of the 2 stimuli, a circle and a cross, varied on the horizontal (right or left) dimension, whereas the position of the 2 responses varied along the depth (near or far) dimension. No Simon effect was found.

  19. Erythritol reduces small intestinal glucose absorption, increases muscle glucose uptake, improves glucose metabolic enzymes activities and increases expression of Glut-4 and IRS-1 in type 2 diabetic rats.

    PubMed

    Chukwuma, Chika Ifeanyi; Mopuri, Ramgopal; Nagiah, Savania; Chuturgoon, Anil Amichund; Islam, Md Shahidul

    2017-08-02

    Studies have reported that erythritol, a low or non-glycemic sugar alcohol possesses anti-hyperglycemic and anti-diabetic potentials but the underlying mode of actions is not clear. This study investigated the underlying mode of actions behind the anti-hyperglycemic and anti-diabetic potentials of erythritol using different experimental models (experiment 1, 2 and 3). Experiment 1 examined the effects of increasing concentrations (2.5-20%) of erythritol on glucose absorption and uptake in isolated rat jejunum and psoas muscle, respectively. Experiments 2 and 3 examined the effects of a single oral dose of erythritol (1 g/kg bw) on intestinal glucose absorption, gastric emptying and postprandial blood glucose increase, glucose tolerance, serum insulin level, muscle/liver hexokinase and liver glucose-6 phosphatase activities, liver and muscle glycogen contents and mRNA and protein expression of muscle Glut-4 and IRS-1 in normal and type 2 diabetic animals. Experiment 1 revealed that erythritol dose dependently enhanced muscle glucose ex vivo. Experiment 2 demonstrated that erythritol feeding delayed gastric emptying and reduced small intestinal glucose absorption as well as postprandial blood glucose rise, especially in diabetic animals. Experiment 3 showed that erythritol feeding improved glucose tolerance, muscle/liver hexokinase and liver glucose-6 phosphatase activities, glycogen storage and also modulated expression of muscle Glut-4 and IRS-1 in diabetic animals. Data suggest that erythritol may exert anti-hyperglycemic effects not only via reducing small intestinal glucose absorption, but also by increasing muscle glucose uptake, improving glucose metabolic enzymes activity and modulating muscle Glut-4 and IRS-1 mRNA and protein expression. Hence, erythritol may be a useful dietary supplement for managing hyperglycemia, particularly for T2D.

  20. Sensitivity of southern hemisphere westerly wind to boundary conditions for the last glacial maximum

    NASA Astrophysics Data System (ADS)

    Jun, S. Y.; Kim, S. J.; Kim, B. M.

    2017-12-01

    To examine the change in SH westerly wind in the LGM, we performed LGM simulation with sensitivity experiments by specifying the LGM sea ice in the Southern Ocean (SO), ice sheet over Antarctica, and tropical pacific sea surface temperature to CAM5 atmosphere general circulation model (GCM). The SH westerly response to LGM boundary conditions in the CAM5 was compared with those from CMIP5 LGM simulations. In the CAM5 LGM simulation, the SH westerly wind substantially increases between 40°S and 65°S, while the zonal-mean zonal wind decreases at latitudes higher than 65°S. The position of the SH maximum westerly wind moves poleward by about 8° in the LGM simulation. Sensitivity experiments suggest that the increase in SH westerly winds is mainly due to the increase in sea ice in the SO that accounts for 60% of total wind change. In the CMIP5-PMIP3 LGM experiments, most of the models show the slight increase and poleward shift of the SH westerly wind as in the CAM5 experiment. The increased and poleward shifted westerly wind in the LGM obtained in the current model result is consistent with previous model results and some lines of proxy evidence, though opposite model responses and proxy evidence exist for the SH westerly wind change.

  1. Long-term field phytoextraction of zinc/cadmium contaminated soil by Sedum plumbizincicola under different agronomic strategies.

    PubMed

    Deng, Lin; Li, Zhu; Wang, Jie; Liu, Hongyan; Li, Na; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Christie, Peter

    2016-01-01

    In two long-term field experiments the zinc (Zn)/cadmium (Cd) hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) was examined to optimize the phytoextraction of metal contaminated soil by two agronomic strategies of intercropping with maize (Zea mays) and plant densities. Soil total Zn and Cd concentrations decreased markedly after long-term phytoextraction. But shoot biomass and Cd and Zn concentrations showed no significant difference with increasing remediation time. In the intercropping experiment the phytoremediation efficiency in the treatment "S. plumbizincicola intercropped with maize" was higher than in S. plumbizincicola monocropping, and Cd concentrations of corn were below the maximum national limit. In the plant density experiment the phytoremediation efficiency increased with increasing plant density and 440,000 plants ha(-1) gave the maximum rate. These results indicated that S. plumbizincicola at an appropriate planting density and intercropped with maize can achieve high remediation efficiency to contaminated soil without affecting the cereal crop productivity. This cropping system combines adequate agricultural production with soil heavy metal phytoextraction.

  2. On Reminder Effects, Drop-Outs and Dominance: Evidence from an Online Experiment on Charitable Giving

    PubMed Central

    Sonntag, Axel; Zizzo, Daniel John

    2015-01-01

    We present the results of an experiment that (a) shows the usefulness of screening out drop-outs and (b) tests whether different methods of payment and reminder intervals affect charitable giving. Following a lab session, participants could make online donations to charity for a total duration of three months. Our procedure justifying the exclusion of drop-outs consists in requiring participants to collect payments in person flexibly and as known in advance and as highlighted to them later. Our interpretation is that participants who failed to collect their positive payments under these circumstances are likely not to satisfy dominance. If we restrict the sample to subjects who did not drop out, but not otherwise, reminders significantly increase the overall amount of charitable giving. We also find that weekly reminders are no more effective than monthly reminders in increasing charitable giving, and that, in our three months duration experiment, standing orders do not increase giving relative to one-off donations. PMID:26252524

  3. Short-Term Compassion Training Increases Prosocial Behavior in a Newly Developed Prosocial Game

    PubMed Central

    Leiberg, Susanne; Klimecki, Olga; Singer, Tania

    2011-01-01

    Compassion has been suggested to be a strong motivator for prosocial behavior. While research has demonstrated that compassion training has positive effects on mood and health, we do not know whether it also leads to increases in prosocial behavior. We addressed this question in two experiments. In Experiment 1, we introduce a new prosocial game, the Zurich Prosocial Game (ZPG), which allows for repeated, ecologically valid assessment of prosocial behavior and is sensitive to the influence of reciprocity, helping cost, and distress cues on helping behavior. Experiment 2 shows that helping behavior in the ZPG increased in participants who had received short-term compassion training, but not in participants who had received short-term memory training. Interindividual differences in practice duration were specifically related to changes in the amount of helping under no-reciprocity conditions. Our results provide first evidence for the positive impact of short-term compassion training on prosocial behavior towards strangers in a training-unrelated task. PMID:21408020

  4. Feature Migration in Time: Reflection of Selective Attention on Speech Errors

    PubMed Central

    Nozari, Nazbanou; Dell, Gary S.

    2012-01-01

    This paper describes an initial study of the effect of focused attention on phonological speech errors. In three experiments, participants recited four-word tongue-twisters, and focused attention on one (or none) of the words. The attended word was singled out differently in each experiment; participants were under instructions to either avoid errors on the attended word, to stress it, or to say it silently. The experiments showed that all methods of attending to a word decreased errors on that word, while increasing errors on the surrounding words. However, this error increase did not result from a relative increase in phonemic migrations originating from the attended word. This pattern is inconsistent with conceptualizing attention either as higher activation of the attended word or greater inhibition of the unattended words throughout the production of the sequence. Instead, it is consistent with a model which presumes that attention exerts its effect at the time of production of the attended word, without lingering effects on the past or the future. PMID:22268910

  5. [Effects of the recipient's response on the emotions and cognitions of female undergraduates disclosing negative emotional experiences in interpersonal relationships].

    PubMed

    Endo, Hiroko; Yukawa, Shintaro

    2013-04-01

    The relationship between a recipient's response to a disclosure of negative emotional experiences, and the resulting negative emotions, hesitation in self-disclosure (interpersonal and intra-personal hesitation), and negatively-confused thoughts of the person making the disclosure were investigated. Female undergraduates (N=271) were asked to write about angry or sad events in their interpersonal relationships that they had disclosed to someone. Then they completed a questionnaire assessing the recipient's responses, negative emotions such as anger and depression caused by the recipient's responses, hesitation in self-disclosure about the events, and negatively-confused thoughts about the events. The results of covariance structure analysis indicated that a recipient's rejection in response to the disclosure of negative emotional experiences resulted in negative thoughts caused by an increase of negative emotions and hesitation in self-disclosure. The results also showed that a recipient's acceptance also increased depression in the person making the self-disclosure, which intensified the intra-personal hesitation, and increased negatively-confused thoughts.

  6. Measuring the continuum of literacy skills among adults: educational testing and the LAMP experience

    NASA Astrophysics Data System (ADS)

    Guadalupe, Cesar; Cardoso, Manuel

    2011-08-01

    The field of educational testing has become increasingly important for providing different stakeholders and decision-makers with information. This paper discusses basic standards for methodological approaches used in measuring literacy skills among adults. The authors address the increasing interest in skills measurement, the discourses on how this should be done with scientific integrity and UNESCO's experience regarding the Literacy Assessment and Monitoring Programme (LAMP). The increase in interest is due to the evolving notion of literacy as a continuum. Its recognition in surveys and data collection is ensured in the first commitment in section 11 of the Belém Framework for Action. The discourse on how measurements should be carried out concerns the need to find valid parsimonious approaches, also their relevance in different institutional, cultural and linguistic contexts as well as issues of ownership and sustainability. Finally, UNESCO's experience with LAMP shows how important addressing these different issues is in order to equip countries with an approach that is fit for purpose.

  7. Does a Culture of Happiness Increase Rumination Over Failure?

    PubMed

    McGuirk, Lucy; Kuppens, Peter; Kingston, Rosemary; Bastian, Brock

    2017-07-17

    Promoting happiness within society is good for health, but could the overpromotion of happiness have a downside? Across 2 studies, we investigate 2 emotion norms associated with an emphasis on happiness-the importance of (a) seeking positive emotion, and (b) avoiding negative emotion-and whether these norms have implications for how people respond to, and seek to regulate, their negative emotional experiences. In Study 1, we used an experimental design to show that emphasizing the importance of happiness increased rumination in response to failure. In Study 2, we drew on cross-sectional evidence to investigate the other side of this equation, finding that emphasizing the importance of not experiencing negative emotional states (e.g., depression and anxiety) was also associated with increased rumination, and that this had downstream consequences for well-being. Together, the findings suggest that the overpromotion of happiness, and, in turn, the felt social pressure not to experience negative emotional states, has implications for maladaptive responses to negative emotional experiences. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. Modern anti-Semitism and anti-Israeli attitudes.

    PubMed

    Cohen, Florette; Jussim, Lee; Harber, Kent D; Bhasin, Gautam

    2009-08-01

    Anti-Semitism is resurgent throughout much of the world. A new theoretical model of anti-Semitism is presented and tested in 3 experiments. The model proposes that mortality salience increases anti-Semitism and that anti-Semitism often manifests as hostility toward Israel. Study 1 showed that mortality salience led to greater levels of anti-Semitism and lowered support for Israel. This effect occurred only in a bogus pipeline condition, indicating that social desirability masks hostility toward Jews and Israel. Study 2 showed that mortality salience caused Israel, but no other country, to perceptually loom large. Study 3 showed that mortality salience increased punitiveness toward Israel's human rights violations more than it increased hostility toward the identical human rights violations committed by Russia or India. Collectively, results suggest that Jews constitute a unique cultural threat to many people's worldviews, that anti-Semitism causes hostility to Israel, and that hostility to Israel may feed back to increase anti-Semitism.

  9. Marine CDOM accumulation during a coastal Arctic mesocosm experiment: No response to elevated pCO2 levels

    NASA Astrophysics Data System (ADS)

    Pavlov, Alexey K.; Silyakova, Anna; Granskog, Mats A.; Bellerby, Richard G. J.; Engel, Anja; Schulz, Kai G.; Brussaard, Corina P. D.

    2014-06-01

    A large-scale multidisciplinary mesocosm experiment in an Arctic fjord (Kongsfjorden, Svalbard; 78°56.2'N) was used to study Arctic marine food webs and biogeochemical elements cycling at natural and elevated future carbon dioxide (CO2) levels. At the start of the experiment, marine-derived chromophoric dissolved organic matter (CDOM) dominated the CDOM pool. Thus, this experiment constituted a convenient case to study production of autochthonous CDOM, which is typically masked by high levels of CDOM of terrestrial origin in the Arctic Ocean proper. CDOM accumulated during the experiment in line with an increase in bacterial abundance; however, no response was observed to increased pCO2 levels. Changes in CDOM absorption spectral slopes indicate that bacteria were most likely responsible for the observed CDOM dynamics. Distinct absorption peaks (at 330 and 360 nm) were likely associated with mycosporine-like amino acids (MAAs). Due to the experimental setup, MAAs were produced in absence of ultraviolet exposure providing evidence for MAAs to be considered as multipurpose metabolites rather than simple photoprotective compounds. We showed that a small increase in CDOM during the experiment made it a major contributor to total absorption in a range of photosynthetically active radiation (PAR, 400-700 nm) and, therefore, is important for spectral light availability and may be important for photosynthesis and phytoplankton groups composition in a rapidly changing Arctic marine ecosystem.

  10. Realistic Free-Spins Features Increase Preference for Slot Machines.

    PubMed

    Taylor, Lorance F; Macaskill, Anne C; Hunt, Maree J

    2017-06-01

    Despite increasing research into how the structural characteristics of slot machines influence gambling behaviour there have been no experimental investigations into the effect of free-spins bonus features-a structural characteristic that is commonly central to the design of slot machines. This series of three experiments investigated the free-spins feature using slot machine simulations to determine whether participants allocate more wagers to a machine with free spins, and, which components of free-spins features drive this preference. In each experiment, participants were exposed to two computer-simulated slot machines-one with a free-spins feature or similar bonus feature and one without. Participants then completed a testing phase where they could freely switch between the two machines. In Experiment 1, participants did not prefer the machine with a simple free-spins feature. In Experiment 2 the free-spins feature incorporated additional elements such as sounds, animations, and an increased win frequency; participants preferred to gamble on this machine. The Experiment 3 "bonus feature" machine resembled the free spins machine in Experiment 2 except spins were not free; participants showed a clear preference for this machine also. These findings indicate that (1) free-spins features have a major influence over machine choice and (2) the "freeness" of the free-spins bonus features is not an important driver of preference, contrary to self-report and interview research with gamblers.

  11. [Removal of volatile organic compounds in soils by soil vapor extraction (SVE)].

    PubMed

    Yin, Fu-xiang; Zhang, Sheng-tian; Zhao, Xin; Feng, Ke; Lin, Yu-suo

    2011-05-01

    An experiment study has been carried out to investigate effects of the diameter of soil columns, the size of soil particulate and different contaminants on efficiency of simulated soil vapor extraction (SVE). Experiments with benzene, toluene, ethylbenzene and n-propylbenzene contaminated soils showed that larger bottom area/soil height (S/H) of the columns led to higher efficiency on removal of contaminants. Experiments with contaminated soils of different particulate size showed that the efficiency of SVE decreased with increases in soil particulate size, from 10 mesh to between 20 mesh and 40 mesh and removal of contaminants in soils became more difficult. Experiments with contaminated soils under different ventilation rates suggested that soil vapor extraction at a ventilation rate of 0.10 L x min(-1) can roughly remove most contaminants from the soils. Decreasing of contaminants in soils entered tailing stages after 12 h, 18 h and 48 h for benzene, toluene and ethylbenzene, respectively. Removal rate of TVOCs (Total VOCs) reached a level as high as 99.52%. The results of the experiment have indicated that molecule structure and properties of the VOCs are also important factors which have effects on removal rates of the contaminants. Increases in carbon number on the benzene ring, decreases in vapor pressure and volatile capability resulted in higher difficulties in soil decontamination. n-propylbenzene has a lower vapor pressure than toluene and ethylbenzene which led to a significant retard effect on desorption and volatilization of benzene and ethylbenzene.

  12. Learning the names of people: the role of image mediators.

    PubMed

    Groninger, L D; Groninger, D H; Stiens, J

    1995-06-01

    Four experiments are reported involving the effects of bizarre and common imagery mediation techniques on the learning and 1-week retention of surnames, given videotaped faces as cues. The videotapes contained 24 undergraduates who were photographed from about the chest up, and who introduced themselves at a 20-second rate. Experiment 1 showed that for both concrete and abstract names, immediate recall of the list was better under imagery mediation instructions than under control instructions. Experiment 2 studied the same conditions using immediate recognition memory of the list as a retrieval measure for the names, and found, despite ceiling effects, that bizarre imagery instructions facilitated recognition for concrete names. Experiment 3 showed that immediate recall could be improved if subjects were given an image mediator for every face-name pair as opposed to generating their own image mediators. Experiment 4 yielded three important findings: (a) 84% of the variance in the 1-week retention of initially recalled names was explained by the presence of absence of the original mediator during 1-week recall; (b) instructions to form image mediators facilitate recall not because image mediators are more effective than other types of mediators, but because they increase the likelihood that a mediator will be formed; (c) 1-week retention could be enhanced with an increased focus during encoding on the points where the mediation process is most likely to fail. The results of these studies are discussed within the context of mediation model wherein recall can fail at any of four stages.

  13. Microgravity and bone cell mechanosensitivity: FLOW experiment during the DELTA mission

    NASA Astrophysics Data System (ADS)

    Bacabac, Rommel G.; Van Loon, Jack J. W. A.; de Blieck-Hogervorst, Jolanda M. A.; Semeins, Cor M.; Zandieh-Doulabi, Behrouz; Helder, Marco N.; Smit, Theo H.; Klein-Nulend, Jenneke

    2007-09-01

    The catabolic effects of microgravity on mineral metabolism in bone organ cultures might be explained as resulting from an exceptional form of disuse. It is possible that the mechanosensitivity of bone cells is altered under near weightlessness conditions, which likely contributes to disturbed bone metabolism observed in astronauts. In the experiment "FLOW", we tested whether the production of early signaling molecules that are involved in the mechanical load-induced osteogenic response by bone cells is changed under microgravity conditions. FLOW was one of the Biological experiment entries to the Dutch Soyuz Mission "DELTA" (Dutch Expedition for Life Science, Technology and Atmospheric Research). FLOW was flown by the Soyuz craft, launched on April 19, 2004, on its way to the International Space Station. Primary osteocytes, osteoblasts, and periosteal fibroblasts were incubated in plunger boxes, developed by Centre for Concepts in Mechatronics, using plunger activation events for single pulse fluid shear stress stimulations. Due to unforeseen hardware complications, results from in-flight cultures are considered lost. Ground control experiments showed an accumulative increase of NO in medium for osteocytes (as well as for osteoblasts and periosteal fibroblasts). Data from the online-NO sensor showed that the NO produced in medium by osteocytes increased sharply after pulse shear stress stimulations. COX-2 mRNA expression revealed high levels in osteoblasts compared to the other cell types tested. In conclusion, preparations for the FLOW experiment and preliminary ground results indicate that the FLOW setup is viable for a future flight opportunity.

  14. [Development and evaluation of fertilizers cemented and coated with organic-inorganic materials].

    PubMed

    Xiao, Qiang; Wang, Jia-Chen; Zuo, Qiang; Zhang, Lin; Liu, Bao-Cun; Zhao, Tong-Ke; Zou, Guo-Yuan; Xu, Qiu-Ming

    2010-01-01

    Four kinds of organic-inorganic cementing and coating materials were prepared by a coating method using water as the solvent, and the corresponding cemented and coated fertilizers (B2, PS, F2, and F2F) were produced by disc pelletizer. The tests on the properties of these fertilizers showed that the granulation rate, compression strength, and film-forming rate were B2 > PS > F2 > F2F. Soil column leaching experiment showed that the curve of accumulated nitrogen-dissolving rate was the gentlest for B2. In 48 days, the accumulated nitrogen-dissolving rate was in the order of B2, 54.65% < PS, 56.16% < F2, 59.47%, < F2F, 63.12%. Field experiment showed that compared with the same application amount of NPK, all the test fertilizers had better effects on corn yield, among which, B2 was the best, with the corn yield and fertilizer use efficiency increased by 19.72% and 20.30%, respectively. The yield-increasing effect of other test fertilizers was in the order of PS > F2 > F2F.

  15. A Theory of Age-Dependent Mutation and Senescence

    PubMed Central

    Moorad, Jacob A.; Promislow, Daniel E. L.

    2008-01-01

    Laboratory experiments show us that the deleterious character of accumulated novel age-specific mutations is reduced and made less variable with increased age. While theories of aging predict that the frequency of deleterious mutations at mutation–selection equilibrium will increase with the mutation's age of effect, they do not account for these age-related changes in the distribution of de novo mutational effects. Furthermore, no model predicts why this dependence of mutational effects upon age exists. Because the nature of mutational distributions plays a critical role in shaping patterns of senescence, we need to develop aging theory that explains and incorporates these effects. Here we propose a model that explains the age dependency of mutational effects by extending Fisher's geometrical model of adaptation to include a temporal dimension. Using a combination of simple analytical arguments and simulations, we show that our model predicts age-specific mutational distributions that are consistent with observations from mutation-accumulation experiments. Simulations show us that these age-specific mutational effects may generate patterns of senescence at mutation–selection equilibrium that are consistent with observed demographic patterns that are otherwise difficult to explain. PMID:18660535

  16. [Ambulatory pediatric surgery: 25 years of experience].

    PubMed

    González Landa, G; Sánchez-Ruiz, I; Prado, C; Azcona, I; Sánchez, C

    2000-10-01

    The objectives of this study are: collect 25 years of experience with ambulatory pediatric surgery in The Pediatric Surgery Service of Hospital de Cruces, present the results of a parents-patient satisfaction survey and show the estimated money savings in the last five years. In the period 1973-1997, 19,934 children (56% of the total surgical cases) were operated with ambulatory surgery, and have been grouped in five quinquenia, showing a constant increase of the percentage of ambulatory surgery. General surgery and ENT are the specialities that more frequently uses this type of surgery (72.4% and 68.6% of the surgical cases of each speciality, respectively, in the last ten years). In general surgery inguinal hernia is the most frequent diagnosis with an increase of orchidopexy in the last five years. ENT is doing ambulatory tonsilectomies in the last ten years. The prolonged recovery stay and unanticipated admissions are rare, usually due to vomiting. The parents satisfaction survey shows great acceptancy, although 13% preferred an overnight postoperative stay. The estimated money saved in the last quinquenia has been important.

  17. Complex regional pain syndrome (CRPS) or continuous unilateral distal experimental pain stimulation in healthy subjects does not bias visual attention towards one hemifield.

    PubMed

    Filippopulos, Filipp M; Grafenstein, Jessica; Straube, Andreas; Eggert, Thomas

    2015-11-01

    In natural life pain automatically draws attention towards the painful body part suggesting that it interacts with different attentional mechanisms such as visual attention. Complex regional pain syndrome (CRPS) patients who typically report on chronic distally located pain of one extremity may suffer from so-called neglect-like symptoms, which have also been linked to attentional mechanisms. The purpose of the study was to further evaluate how continuous pain conditions influence visual attention. Saccade latencies were recorded in two experiments using a common visual attention paradigm whereby orientating saccades to cued or uncued lateral visual targets had to be performed. In the first experiment saccade latencies of healthy subjects were measured under two conditions: one in which continuous experimental pain stimulation was applied to the index finger to imitate a continuous pain situation, and one without pain stimulation. In the second experiment saccade latencies of patients suffering from CRPS were compared to controls. The results showed that neither the continuous experimental pain stimulation during the experiment nor the chronic pain in CRPS led to an unilateral increase of saccade latencies or to a unilateral increase of the cue effect on latency. The results show that unilateral, continuously applied pain stimuli or chronic pain have no or only very limited influence on visual attention. Differently from patients with visual neglect, patients with CRPS did not show strong side asymmetries of saccade latencies or of cue effects on saccade latencies. Thus, neglect-like clinical symptoms of CRPS patients do not involve the allocation of visual attention.

  18. Effects of syllable-initial voicing and speaking rate on the temporal characteristics of monosyllabic words.

    PubMed

    Allen, J S; Miller, J L

    1999-10-01

    Two speech production experiments tested the validity of the traditional method of creating voice-onset-time (VOT) continua for perceptual studies in which the systematic increase in VOT across the continuum is accompanied by a concomitant decrease in the duration of the following vowel. In experiment 1, segmental durations were measured for matched monosyllabic words beginning with either a voiced stop (e.g., big, duck, gap) or a voiceless stop (e.g., pig, tuck, cap). Results from four talkers showed that the change from voiced to voiceless stop produced not only an increase in VOT, but also a decrease in vowel duration. However, the decrease in vowel duration was consistently less than the increase in VOT. In experiment 2, results from four new talkers replicated these findings at two rates of speech, as well as highlighted the contrasting temporal effects on vowel duration of an increase in VOT due to a change in syllable-initial voicing versus a change in speaking rate. It was concluded that the traditional method of creating VOT continua for perceptual experiments, although not perfect, approximates natural speech by capturing the basic trade-off between VOT and vowel duration in syllable-initial voiced versus voiceless stop consonants.

  19. Elevated body temperature and increased blood vessel sensitivity in spontaneously hypertensive rats.

    PubMed

    Price, J M; Wilmoth, F R

    1990-04-01

    Body temperature (BT) was significantly greater in spontaneously hypertensive rats (SHR) than in Wistar-Kyoto (WKY) rats regardless of the time of day, length of rectal probe, sex, age, or commercial vendor. Bath temperature (theta) for excised aortic rings was controlled by a thermoelectric Peltier module with an accuracy of 0.1 degree C. At peak force in individual contractions of norepinephrine (NE) dose-response experiments, theta was changed from 37 to 39 degrees C. Active and resting wall tension (Tw) were increased, and the mean effective dose (ED50) was decreased in the SHR aorta with and without endothelium. For the WKY aorta, active and resting Tw were increased, but ED50 was the same with and without endothelium. These results were supported by experiments where theta was decreased from 39 to 37 degrees C and by experiments on Sprague-Dawley rats. Potassium dose-response experiments with aorta from SHR and WKY rats show an increase in sensitivity at 39 degrees C, but active Tw is the same at 39 and 37 degrees C. When compared at the BT of each rat, the NE ED50 was lower and resting Tw was higher in the SHR aorta than in the WKY aorta, but active Tw was the same.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Valence and the development of immediate and long-term false memory illusions.

    PubMed

    Howe, Mark L; Candel, Ingrid; Otgaar, Henry; Malone, Catherine; Wimmer, Marina C

    2010-01-01

    Across five experiments we examined the role of valence in children's and adults' true and false memories. Using the Deese/Roediger-McDermott paradigm and either neutral or negative-emotional lists, both adults' (Experiment 1) and children's (Experiment 2) true recall and recognition was better for neutral than negative items, and although false recall was also higher for neutral items, false recognition was higher for negative items. The last three experiments examined adults' (Experiment 3) and children's (Experiments 4 and 5) 1-week long-term recognition of neutral and negative-emotional information. The results replicated the immediate recall and recognition findings from the first two experiments. More important, these experiments showed that although true recognition decreased over the 1-week interval, false recognition of neutral items remained unchanged whereas false recognition of negative-emotional items increased. These findings are discussed in terms of theories of emotion and memory as well as their forensic implications.

  1. Implicit self-esteem compensation: automatic threat defense.

    PubMed

    Rudman, Laurie A; Dohn, Matthew C; Fairchild, Kimberly

    2007-11-01

    Four experiments demonstrated implicit self-esteem compensation (ISEC) in response to threats involving gender identity (Experiment 1), implicit racism (Experiment 2), and social rejection (Experiments 3-4). Under conditions in which people might be expected to suffer a blow to self-worth, they instead showed high scores on 2 implicit self-esteem measures. There was no comparable effect on explicit self-esteem. However, ISEC was eliminated following self-affirmation (Experiment 3). Furthermore, threat manipulations increased automatic intergroup bias, but ISEC mediated these relationships (Experiments 2-3). Thus, a process that serves as damage control for the self may have negative social consequences. Finally, pretest anxiety mediated the relationship between threat and ISEC (Experiment 3), whereas ISEC negatively predicted anxiety among high-threat participants (Experiment 4), suggesting that ISEC may function to regulate anxiety. The implications of these findings for automatic emotion regulation, intergroup bias, and implicit self-esteem measures are discussed. (c) 2007 APA, all rights reserved.

  2. Investigation of flame structure and burning intensity of partially premixed methane enrichment of syngas using OH-PLIF and kinetic simulation

    NASA Astrophysics Data System (ADS)

    Pu, Ge; Huang, Beibei; Zhang, Xun; Du, Jiantai; Zhu, Tuanhui; Chen, Bei

    2018-05-01

    Various experiments were conducted to study the combustion characteristics of partially premixed methane enrichment of syngas by using the OH-PLIF technique. Experiments were conducted on a co-flow burner, and the methane concentration (XCH4 = CH4/(H2+CO+CH4)) was varied from 0 to 20%, the overall equivalence ratio was varied from 0.4 to 1.2 and the inner equivalence ratio was varied from 1.5 to 3.5. Kinetic simulation was conducted by using OPPDIF module of CHEMKIN-Pro software. Results show that an increase in XCH4 and ϕoverall weakens the OH signal intensity. Adding methane into the fuel greatly increases the height of the inner flame front, and the increase of methane concentration has a negative effect on flame propagation speed. Meanwhile, simulation results remain consistent with the experiments. The main OH radical production reaction changes from R46: H+HO2 = 2OH to R38: H+O2 = O+OH when methane concentration contained in the fuel mixture increases. Sensitivity analysis also indicates that reaction which plays a dominant effect on temperature changes with the increase of methane concentration.

  3. The Impact of a Postgraduate Learning Experience on the Confidence of General Dental Practitioners.

    PubMed

    Fine, Peter; Louca, Chris; Leung, Albert

    2017-04-26

    This study aimed to explore the relationship between participating in a learning experience and the ensuing changes in confidence. A self-selected group of General Dental Practitioners (GDPs) entered a five-year, part-time postgraduate master's training programme in restorative dentistry. Confidence in communication with patients and technical skills were measured at the start of the programme by questionnaire and at the conclusion of the programme by questionnaire and personal interview. A total of 72 clinicians started the programme; 27% ( n = 20) completed the master's degree. Assessment of confidence revealed a spread from 4/10 to 10/10 for communication with patients and clinical skills in restorative dentistry before the programme started. A total of 15% ( n = 11) volunteered for interview. Analysis of qualitative data revealed (i) a perceived increase in confidence from all clinicians; (ii) a perceived greater ability to treat patients; (iii) an increase in treatment options being offered to patients; (iv) a perceived increase in treatment uptake by patients; and (v) greater job opportunities. The study showed a positive relationship between the learning experience and the perceived increase in confidence of clinicians. The increase in confidence manifested itself in better communication and clinical skills.

  4. The Impact of a Postgraduate Learning Experience on the Confidence of General Dental Practitioners

    PubMed Central

    Fine, Peter; Louca, Chris; Leung, Albert

    2017-01-01

    This study aimed to explore the relationship between participating in a learning experience and the ensuing changes in confidence. A self-selected group of General Dental Practitioners (GDPs) entered a five-year, part-time postgraduate master’s training programme in restorative dentistry. Confidence in communication with patients and technical skills were measured at the start of the programme by questionnaire and at the conclusion of the programme by questionnaire and personal interview. A total of 72 clinicians started the programme; 27% (n = 20) completed the master’s degree. Assessment of confidence revealed a spread from 4/10 to 10/10 for communication with patients and clinical skills in restorative dentistry before the programme started. A total of 15% (n = 11) volunteered for interview. Analysis of qualitative data revealed (i) a perceived increase in confidence from all clinicians; (ii) a perceived greater ability to treat patients; (iii) an increase in treatment options being offered to patients; (iv) a perceived increase in treatment uptake by patients; and (v) greater job opportunities. The study showed a positive relationship between the learning experience and the perceived increase in confidence of clinicians. The increase in confidence manifested itself in better communication and clinical skills. PMID:29563422

  5. Predicting Insulin Absorption and Glucose Uptake during Exercise in Type 1 Diabetes

    NASA Astrophysics Data System (ADS)

    Frank, Spencer; Hinshaw, Ling; Basu, Rita; Szeri, Andrew; Basu, Ananda

    2017-11-01

    A dose of insulin infused into subcutaneous tissue has been shown to absorb more quickly during exercise, potentially causing hypoglycemia in persons with type 1 diabetes. We develop a model that relates exercise-induced physiological changes to enhanced insulin-absorption (k) and glucose uptake (GU). Drawing on concepts of the microcirculation we derive a relationship that reveals that k and GU are mainly determined by two physiological parameters that characterize the tissue: the tissue perfusion rate (Q) and the capillary permeability surface area (PS). Independently measured values of Q and PS from the literature are used in the model to make predictions of k and GU. We compare these predictions to experimental observations of healthy and diabetic patients that are given a meal followed by rest or exercise. The experiments show that during exercise insulin concentrations significantly increase and that glucose levels fall rapidly. The model predictions are consistent with the experiments and show that increases in Q and PS directly increase k and GU. This mechanistic understanding provides a basis for handling exercise in control algorithms for an artificial pancreas. Now at University of British Columbia.

  6. Elaborations on sexual assault on dates among Israeli students: risk, detrimental effect, and resilience factors.

    PubMed

    Shechory Bitton, Mally; Ben-David, Sarah

    2014-12-01

    The current study of 668 Israeli male and female students examines the prevalence of gendered risk factors for sexual assault (SA) on dates, posttraumatic stress disorder (PTSD) as a detrimental effect of SA, and self-efficacy as resiliency to refuse unwanted sex following SA. Two different sets of risk factors that increased the likelihood of SA on dates emerged from the hierarchical regression. Sexual experience, use of drugs, and private location increased the risk of being SA victims among males, whereas sexual experience, perceived provocative behavior, and alcohol use increased the risk among females. In addition, PTSD and self-efficacy to refuse unwanted sex following SA on dates were predicted by the extent of coercive sexual victimization. PTSD was also predicted by subjective perception of sexual behavior and rape myths, whereas efficacy was predicted by private location. The findings contribute to the literature by showing the contribution of various risk factors to experiencing SA, and by showing SA effect on PTSD and self-efficacy. © The Author(s) 2013.

  7. “Ductile to brittle” transition in thermally stable antigorite gouge at mantle pressures

    USGS Publications Warehouse

    Proctor, Brooks; Hirth, Greg

    2016-01-01

    General shear experiments on antigorite-rich serpentinite show a transition from ductile (distributed) to brittle (localized) deformation with increasing temperature from 300°C to 500°C at confining pressures from 1 to 2 GPa. The coefficient of friction associated with slip along fractures decreases from 0.23 to 0.07 with an increase in temperature from 300°C to 500°C. Velocity stepping experiments exhibit a positive rate dependence, as parameterized by a-b values, that decrease modestly with increasing temperature from ~0.015 at 300°C to ~0.01 at 500°C. Fractures contain fine-grained foliated antigorite, and there is no evidence of dehydration. All samples have a moderate foliation and show microstructural evidence for both plastic and brittle deformation mechanisms. Under certain conditions the transition to brittle deformation, at high pressures and temperatures in antigorite, might generate earthquakes, which could explain the occurrence of some intermediate-depth seismicity within subduction zones in serpentinized regions that are too cold to induce dehydration.

  8. Kinetics of Cd(ii) adsorption and desorption on ferrihydrite: experiments and modeling.

    PubMed

    Liang, Yuzhen; Tian, Lei; Lu, Yang; Peng, Lanfang; Wang, Pei; Lin, Jingyi; Cheng, Tao; Dang, Zhi; Shi, Zhenqing

    2018-05-15

    The kinetics of Cd(ii) adsorption/desorption on ferrihydrite is an important process affecting the fate, transport, and bioavailability of Cd(ii) in the environment, which was rarely systematically studied and understood at quantitative levels. In this work, a combination of stirred-flow kinetic experiments, batch adsorption equilibrium experiments, high-resolution transmission electron microscopy (HR-TEM), and mechanistic kinetic modeling were used to study the kinetic behaviors of Cd(ii) adsorption/desorption on ferrihydrite. HR-TEM images showed the open, loose, and sponge-like structure of ferrihydrite. The batch adsorption equilibrium experiments revealed that higher pH and initial metal concentration increased Cd(ii) adsorption on ferrihydrite. The stirred-flow kinetic results demonstrated the increased adsorption rate and capacity as a result of the increased pH, influent concentration, and ferrihydrite concentration. The mechanistic kinetic model successfully described the kinetic behaviors of Cd(ii) during the adsorption and desorption stages under various chemistry conditions. The model calculations showed that the adsorption rate coefficients varied as a function of solution chemistry, and the relative contributions of the weak and strong ferrihydrite sites for Cd(ii) binding varied with time at different pH and initial metal concentrations. Our model is able to quantitatively assess the contributions of each individual ferrihydrite binding site to the overall Cd(ii) adsorption/desorption kinetics. This study provided insights into the dynamic behavior of Cd(ii) and a predictive modeling tool for Cd(ii) adsorption/desorption kinetics when ferrihydrite is present, which may be helpful for the risk assessment and management of Cd contaminated sites.

  9. Inhibition of return is not impaired but masked by increased facilitation in schizophrenia patients.

    PubMed

    Kalogeropoulou, Fenia; Woodruff, Peter W R; Vivas, Ana B

    2015-01-01

    When attention is attracted to an irrelevant location, performance on a subsequent target is hindered at that location in relation to novel, not previously attended, locations. This phenomenon is known as inhibition of return (IOR). Previous research has shown that IOR is not observed, or its onset is delayed, in schizophrenia patients. In the present study, the authors tested the hypothesis that IOR may be intact but masked by increased facilitation in schizophrenia patients. To test this hypothesis, they used a procedure that usually reduces or eliminates the early facilitation. In the first experiment, the authors used the typical single-cue IOR task in the group of healthy adults (N = 28) and in a group of schizophrenia patients (N = 32). In the second experiment, they manipulated cue-target discriminability by presenting spatially overlapping cues and targets where the cues were more intense than the targets. In Experiment 1, they did not find significant IOR effects in the group of schizophrenia patients, even with cue-target intervals as long as 3,200 ms. However, in Experiment 2, IOR effects were significant at the 350- and 450-ms cue-target intervals for healthy and patients, respectively. This is the first study that shows that schizophrenia patients can actually show inhibitory effects very similar to healthy controls, even when no help is provided to shift their attention away from the irrelevant location. The authors suggest that inhibition is intact in schizophrenia patients, but it is usually masked by increased facilitation. PsycINFO Database Record (c) 2015 APA, all rights reserved.

  10. Collaboration can improve individual recognition memory: evidence from immediate and delayed tests.

    PubMed

    Rajaram, Suparna; Pereira-Pasarin, Luciane P

    2007-02-01

    In two experiments, we tested the effects of collaboration on individual recognition memory. In Experiment 1, participants studied pictures and words either for meaning or for surface properties and made recognition memory judgments individually either following group discussion among 3 members (collaborative condition) or in the absence of discussion (noncollaborative condition). Levels of processing and picture superiority effects were replicated, and collaboration significantly increased individual recognition memory. Experiment 2 replicated this positive effect and showed that even though memory sensitivity declined at longer delays (48 h and 1 week), collaboration continued to exert a positive influence. These findings show that (1) consensus is not necessary for producing benefits of collaboration on individual recognition, (2) collaborative facilitation on individual memory is robust, and (3) collaboration enhances individual memory further if conditions predispose individual accuracy in the absence of collaboration.

  11. Short- and Mid-Term Effects of Violent Victimization on Delinquency: A Multilevel Growth-Curve Modeling Approach.

    PubMed

    Kim, Young S; Lo, Celia C

    2016-10-01

    The present study investigates how adolescents' experiences of violent victimization exert short- and mid-term effects on their involvement in delinquency. The study compares and contrasts delinquency trajectories of youths whose experiences of violent victimization differ. A multilevel growth-curve modeling approach is applied to analyze data from five waves of the National Youth Survey. The results show that, although delinquency involvement increases as youths experience violent victimization, delinquency trajectories differ with the type of violent victimization, specifically, parental versus non-parental victimization. Violent victimization by parents produced a sharp initial decline in delinquency (short-term effect) followed by a rapid acceleration (mid-term effect). In turn, non-parental violence showed a stable trend over time. The findings have important implications for prevention and treatment services. © The Author(s) 2015.

  12. Hydraulic parameters in eroding rills and their influence on detachment processes

    NASA Astrophysics Data System (ADS)

    Wirtz, Stefan; Seeger, Manuel; Zell, Andreas; Wagner, Christian; Wengel, René; Ries, Johannes B.

    2010-05-01

    In many experiments as well in laboratory as in field experiments the correlations between the detachment rate and different hydraulic parameters are calculated. The used parameters are water depth, runoff, shear stress, unit length shear force, stream power, Reynolds- and Froude number. The investigations show even contradictory results. In most soil erosion models like the WEPP model, the shear stress is used to predict soil detachment rates. But in none of the WEPP datasets, the shear stress showed the best correlation to the detachment rate. In this poster we present the results of several rill experiments in Andalusia from 2008 and 2009. With the used method, it is possible to measure the needed factors to calculate the mentioned parameters. Water depth is measured by an ultrasonic sensor, the runoff values are calculated by combining flow velocity and flow diameter. The parameters wetted perimeter, flow diameter and hydraulic radius can be calculated from the measured rill cross sections and the measured water levels. In the sample density values, needed for calculation of shear stress, unit length shear force and stream power, the sediment concentration and the grain density are are considered. The viscosity of the samples was measured with a rheometer. The result of this measurements shows, that there is a very high linear correlation (R² = 0.92) between sediment concentration and the dynamic viscosity. The viscosity seems to be an important factor but it is only used in the Reynolds-number-equation, in other equations it is neglected. But the viscosity value increases with increasing sediment concentration and hence the influence also increases and the in multiclications negiligible viscosity value of 1 only counts for clear water. The correlations between shear stress, unit length shear force and stream power at the x-axis and the detachment rate at the ordinate show, that there is not one fixed parameter that always displays the best correlation to the detachment rate. The best hit does not change from one experiment to another, it changes from one measuring point to another. Different processes in rill erosion are responsible for the changing correlations. In some cases no one of the parameters shows an acceptable correlation to the soil detachment, because these factors describe fluvial processes. Our experiments show, that not the fluvial processes cause the main sediment procduction in the rills, but bank failure or knickpoint and headcut retreat and these processes are more gravitative than fluvial. Another sediment producing process is the abrupt spill over of plunge pools, a process not realy fluvial and not realy gravitativ. In some experiments, the highest sediment concentrations were measured at the slowly flowing waterfront that only transports the loose material. But all these processes are not considered in soil erosion models. Hence, hydraulic parameters alone are not sufficient to predict detachment rates. They cover the fluvial incising in the rill's bottom, but the main sediment sources are not considered satisying in its equations.

  13. From discrimination to internalized mental illness stigma: The mediating roles of anticipated discrimination and anticipated stigma.

    PubMed

    Quinn, Diane M; Williams, Michelle K; Weisz, Bradley M

    2015-06-01

    Internalizing mental illness stigma is related to poorer well-being, but less is known about the factors that predict levels of internalized stigma. This study explored how experiences of discrimination relate to greater anticipation of discrimination and devaluation in the future and how anticipation of stigma in turn predicts greater stigma internalization. Participants were 105 adults with mental illness who self-reported their experiences of discrimination based on their mental illness, their anticipation of discrimination and social devaluation from others in the future, and their level of internalized stigma. Participants were approached in several locations and completed surveys on laptop computers. Correlational analyses indicated that more experiences of discrimination due to one's mental illness were related to increased anticipated discrimination in the future, increased anticipated social stigma from others, and greater internalized stigma. Multiple serial mediator analyses showed that the effect of experiences of discrimination on internalized stigma was fully mediated by increased anticipated discrimination and anticipated stigma. Experiences of discrimination over one's lifetime may influence not only how much future discrimination people with mental illness are concerned with but also how much they internalize negative feelings about the self. Mental health professionals may need to address concerns with future discrimination and devaluation in order to decrease internalized stigma. (c) 2015 APA, all rights reserved).

  14. Tapping in synchrony with a perturbed metronome: the phase correction response to small and large phase shifts as a function of tempo.

    PubMed

    Repp, Bruno H

    2011-01-01

    When tapping is paced by an auditory sequence containing small phase shift (PS) perturbations, the phase correction response (PCR) of the tap following a PS increases with the baseline interonset interval (IOI), leading eventually to overcorrection (B. H. Repp, 2008). Experiment 1 shows that this holds even for fixed-size PSs that become imperceptible as the IOI increases (here, from 400 to 1200 ms). Earlier research has also shown (but only for IOI=500 ms) that the PCR is proportionally smaller for large than for small PSs (B. H. Repp, 2002a, 2002b). Experiment 2 introduced large PSs and found smaller PCRs than in Experiment 1, at all of the same IOIs. In Experiments 3A and 3B, the author investigated whether the change in slope of the sigmoid function relating PCR and PS magnitudes occurs at a fixed absolute or relative PS magnitude across different IOIs (600, 1000, 1400 ms). The results suggest no clear answer; the exact shape of the function may depend on the range of PSs used in an experiment. Experiment 4 examined the PCR in the IOI range from 1000 to 2000 ms and found overcorrection throughout, but with the PCR increasing much more gradually than in Experiment 1. These results provide important new information about the phase correction process and pose challenges for models of sensorimotor synchronization, which presently cannot explain nonlinear PCR functions and overcorrection. Copyright © Taylor & Francis Group, LLC

  15. Evaluation of Gastrointestinal Leakage in Multiple Enteric Inflammation Models in Chickens.

    PubMed

    Kuttappan, Vivek A; Vicuña, Eduardo A; Latorre, Juan D; Wolfenden, Amanda D; Téllez, Guillermo I; Hargis, Billy M; Bielke, Lisa R

    2015-01-01

    Enteric inflammation models can help researchers' study methods to improve health and performance and evaluate various growth promoters and dietary formulations targeted to improve performance in poultry. Oral administration of fluorescein isothiocyanate-dextran (FITC-d; 3-5 kDa) and its pericellular mucosal epithelial leakage are an established marker to evaluate enteric inflammation in multiple species. The present study evaluated different methods to induce gut inflammation in poultry based on FITC-d leakage. Four independent experiments were completed with different inflammation treatment groups, and serum FITC-d and/or retention of FITC-d in GI tract were determined. In experiment 1 (n = 10 birds/treatment, broilers, processed at 14 days), groups included control (CON), dextran sodium sulfate (DSS; drinking water at 0.75%) and feed restriction (FRS; 24 h before processing). Experiment 2 (n = 14 birds/treatment, leghorns, processed at 7 days) included CON, DSS, FRS, and rye-based diet (RBD). In experiments 3 and 4 (n = 15 birds/treatment, broilers, processed at 7 days), groups were CON, DSS, high fat diet (HFD), FRS, and RBD. In all experiments, FRS and RBD treatments showed significantly higher serum FITC-d levels compared to the respective CON. This indicates that FRS and RBD results in disruption of the intact barrier of the gastrointestinal tract (GIT), resulting in increased gut permeability. DSS and HFD groups showed elevation of serum FITC-d levels although the magnitude of difference from respective CON was inconsistent between experiments. FRS was the only treatment which consistently showed elevated retention of FITC-d in GIT in all experiments. The results from present studies showed that FRS and RBD, based on serum FITC-d levels, can be robust models to induce gut leakage in birds in different age and species/strains.

  16. Energy-dense diets increase FGF23, lead to phosphorus retention and promote vascular calcifications in rats

    PubMed Central

    Raya, Ana I.; Rios, Rafael; Pineda, Carmen; Rodriguez-Ortiz, Maria E.; Diez, Elisa; Almaden, Yolanda; Muñoz-Castañeda, Juan R.; Rodriguez, Mariano; Aguilera-Tejero, Escolastico; Lopez, Ignacio

    2016-01-01

    Rats with normal renal function (Experiment 1, n = 12) and uninephrectomized (1/2Nx) rats (Experiment 2, n = 12) were fed diets with normal P (NP) and either normal (NF) or high fat (HF). Rats with intact renal function (Experiment 3, n = 12) were also fed NF or HF diets with high P (HP). Additionally, uremic (5/6Nx) rats (n = 16) were fed HP diets with NF or HF. Feeding the HF diets resulted in significant elevation of plasma FGF23 vs rats fed NF diets: Experiment 1, 593 ± 126 vs 157 ± 28 pg/ml (p < 0.01); Experiment 2, 538 ± 105 vs 250 ± 18 pg/ml (p < 0.05); Experiment 3, 971 ± 118 vs 534 ± 40 pg/ml (p < 0.01). Rats fed HF diets showed P retention and decreased renal klotho (ratio klotho/actin) vs rats fed NF diets: Experiment 1, 0.75 ± 0.06 vs 0.97 ± 0.02 (p < 0.01); Experiment 2, 0.69 ± 0.07 vs 1.12 ± 0.08 (p < 0.01); Experiment 3, 0.57 ± 0.19 vs 1.16 ± 0.15 (p < 0.05). Uremic rats fed HF diet showed more severe vascular calcification (VC) than rats fed NF diet (aortic Ca = 6.3 ± 1.4 vs 1.4 ± 0.1 mg/g tissue, p < 0.001). In conclusion, energy-rich diets increased plasma levels of FGF23, a known risk factor of cardiovascular morbidity and mortality. Even though FGF23 has major phosphaturic actions, feeding HF diets resulted in P retention, likely secondary to decreased renal klotho, and aggravated uremic VC. PMID:27841294

  17. Energy-dense diets increase FGF23, lead to phosphorus retention and promote vascular calcifications in rats.

    PubMed

    Raya, Ana I; Rios, Rafael; Pineda, Carmen; Rodriguez-Ortiz, Maria E; Diez, Elisa; Almaden, Yolanda; Muñoz-Castañeda, Juan R; Rodriguez, Mariano; Aguilera-Tejero, Escolastico; Lopez, Ignacio

    2016-11-14

    Rats with normal renal function (Experiment 1, n = 12) and uninephrectomized (1/2Nx) rats (Experiment 2, n = 12) were fed diets with normal P (NP) and either normal (NF) or high fat (HF). Rats with intact renal function (Experiment 3, n = 12) were also fed NF or HF diets with high P (HP). Additionally, uremic (5/6Nx) rats (n = 16) were fed HP diets with NF or HF. Feeding the HF diets resulted in significant elevation of plasma FGF23 vs rats fed NF diets: Experiment 1, 593 ± 126 vs 157 ± 28 pg/ml (p < 0.01); Experiment 2, 538 ± 105 vs 250 ± 18 pg/ml (p < 0.05); Experiment 3, 971 ± 118 vs 534 ± 40 pg/ml (p < 0.01). Rats fed HF diets showed P retention and decreased renal klotho (ratio klotho/actin) vs rats fed NF diets: Experiment 1, 0.75 ± 0.06 vs 0.97 ± 0.02 (p < 0.01); Experiment 2, 0.69 ± 0.07 vs 1.12 ± 0.08 (p < 0.01); Experiment 3, 0.57 ± 0.19 vs 1.16 ± 0.15 (p < 0.05). Uremic rats fed HF diet showed more severe vascular calcification (VC) than rats fed NF diet (aortic Ca = 6.3 ± 1.4 vs 1.4 ± 0.1 mg/g tissue, p < 0.001). In conclusion, energy-rich diets increased plasma levels of FGF23, a known risk factor of cardiovascular morbidity and mortality. Even though FGF23 has major phosphaturic actions, feeding HF diets resulted in P retention, likely secondary to decreased renal klotho, and aggravated uremic VC.

  18. Narrative event boundaries, reading times, and expectation.

    PubMed

    Pettijohn, Kyle A; Radvansky, Gabriel A

    2016-10-01

    During text comprehension, readers create mental representations of the described events, called situation models. When new information is encountered, these models must be updated or new ones created. Consistent with the event indexing model, previous studies have shown that when readers encounter an event shift, reading times often increase. However, such increases are not consistently observed. This paper addresses this inconsistency by examining the extent to which reading-time differences observed at event shifts reflect an unexpectedness in the narrative rather than processes involved in model updating. In two reassessments of prior work, event shifts known to increase reading time were rated as less expected, and expectedness ratings significantly predicted reading time. In three new experiments, participants read stories in which an event shift was or was not foreshadowed, thereby influencing expectedness of the shift. Experiment 1 revealed that readers do not expect event shifts, but foreshadowing eliminates this. Experiment 2 showed that foreshadowing does not affect identification of event shifts. Finally, Experiment 3 found that, although reading times increased when an event shift was not foreshadowed, they were not different from controls when it was. Moreover, responses to memory probes were slower following an event shift regardless of foreshadowing, suggesting that situation model updating had taken place. Overall, the results support the idea that previously observed reading time increases at event shifts reflect, at least in part, a reader's unexpected encounter with a shift rather than an increase in processing effort required to update a situation model.

  19. Effects on Inter-Personal Memory of Dancing in Time with Others.

    PubMed

    Woolhouse, Matthew H; Tidhar, Dan; Cross, Ian

    2016-01-01

    We report an experiment investigating whether dancing to the same music enhances recall of person-related memory targets. The experiment used 40 dancers (all of whom were unaware of the experiment's aim), two-channel silent-disco radio headphones, a marked-up dance floor, two types of music, and memory targets (sash colors and symbols). In each trial, 10 dancers wore radio headphones and one of four different colored sashes, half of which carried cat symbols. Using silent-disco technology, one type of music was surreptitiously transmitted to half the dancers, while music at a different tempo was transmitted to the remaining dancers. Pre-experiment, the dancers' faces were photographed. Post-experiment, each dancer was presented with the photographs of the other dancers and asked to recall their memory targets. Results showed that same-music dancing significantly enhanced memory for sash color and sash symbol. Our findings are discussed in light of recent eye-movement research that showed significantly increased gaze durations for people observing music-dance synchrony versus music-dance asynchrony, and in relation to current literature on interpersonal entrainment, group cohesion, and social bonding.

  20. Adult age differences in unconscious transference: source confusion or identity blending?

    PubMed

    Perfect, Timothy J; Harris, Lucy J

    2003-06-01

    Eyewitnesses are known often to falsely identify a familiar but innocent bystander when asked to pick out a perpetrator from a lineup. Such unconscious transference errors have been attributed to either identity confusions at encoding or source retrieval errors. Three experiments contrasted younger and older adults in their susceptibility to such misidentifications. Participants saw photographs of perpetrators, then a series of mug shots of innocent bystanders. A week later, they saw lineups containing bystanders (and others containing perpetrators in Experiment 3) and were asked whether any of the perpetrators were present. When younger faces were used as stimuli (Experiments 1 and 3), older adults showed higher rates of transference errors. When older faces were used as stimuli (Experiments 2 and 3), no such age effects in rates of unconscious transference were apparent. In addition, older adults in Experiment 3 showed an own-age bias effect for correct identification of targets. Unconscious transference errors were found to be due to both source retrieval errors and identity confusions, but age-related increases were found only in the latter.

  1. Relative expertise affects N170 during selective attention to superimposed face-character images.

    PubMed

    Ip, Chengteng; Wang, Hailing; Fu, Shimin

    2017-07-01

    It remains unclear whether the N170 of ERPs reflects domain-specific or domain-general visual object processing. In this study, we used superimposed images of a face and a Chinese character such that participants' relative expertise for the two object types was either similar (Experiment 1 and 2) or different (Experiment 3). Experiment 1 showed that N170 amplitude was larger when participants attended to the character instead of the face of a face-character combination. This result was unchanged in Experiment 2, in which task difficulty was selectively increased for the face component of the combined stimuli. Experiment 3 showed that, although this N170 enhancement for attending to characters relative to faces persisted for false characters with recognizable parts, it disappeared for unrecognizable characters. Therefore, N170 amplitude was significantly greater for Chinese characters than for faces presented within a combined image, independent of the relative task difficulty. This result strongly calls N170 face selectivity into question, demonstrating that, contrary to the expectations established by a domain-specific account, N170 is modulated by expertise. © 2017 Society for Psychophysiological Research.

  2. The world can look better: enhancing beauty experience with brain stimulation.

    PubMed

    Cattaneo, Zaira; Lega, Carlotta; Flexas, Albert; Nadal, Marcos; Munar, Enric; Cela-Conde, Camilo J

    2014-11-01

    Aesthetic appreciation is part of our everyday life: it is a subjective judgment we make when looking at a painting, a landscape, or--in fact--at another person. Neuroimaging and electrophysiological evidence suggests that the left dorsolateral prefrontal cortex (DLPFC) plays a critical role in aesthetic judgments. Here, we show that the experience of beauty can be artificially enhanced with brain stimulation. Specifically, we show that aesthetic appreciation of representational paintings and photographs can be increased by applying anodal (excitatory) transcranial direct current stimulation on the left DLPFC. Our results thus show that beauty is in the brain of the beholder, and offer a novel view on the neural networks underlying aesthetic appreciation. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  3. Bayesian inference to identify parameters in viscoelasticity

    NASA Astrophysics Data System (ADS)

    Rappel, Hussein; Beex, Lars A. A.; Bordas, Stéphane P. A.

    2017-08-01

    This contribution discusses Bayesian inference (BI) as an approach to identify parameters in viscoelasticity. The aims are: (i) to show that the prior has a substantial influence for viscoelasticity, (ii) to show that this influence decreases for an increasing number of measurements and (iii) to show how different types of experiments influence the identified parameters and their uncertainties. The standard linear solid model is the material description of interest and a relaxation test, a constant strain-rate test and a creep test are the tensile experiments focused on. The experimental data are artificially created, allowing us to make a one-to-one comparison between the input parameters and the identified parameter values. Besides dealing with the aforementioned issues, we believe that this contribution forms a comprehensible start for those interested in applying BI in viscoelasticity.

  4. Building metamemorial knowledge over time: insights from eye tracking about the bases of feeling-of-knowing and confidence judgments.

    PubMed

    Chua, Elizabeth F; Solinger, Lisa A

    2015-01-01

    Metamemory processes depend on different factors across the learning and memory time-scale. In the laboratory, subjects are often asked to make prospective feeling-of-knowing (FOK) judgments about target retrievability, or are asked to make retrospective confidence judgments (RCJs) about the retrieved target. We examined distinct and shared contributors to metamemory judgments, and how they were built over time. Eye movements were monitored during a face-scene associative memory task. At test, participants viewed a studied scene, then rated their FOK that they would remember the associated face. This was followed by a forced choice recognition test and RCJs. FOK judgments were less accurate than RCJ judgments, showing that the addition of mnemonic experience can increase metacognitive accuracy over time. However, there was also evidence that the given FOK rating influenced RCJs. Turning to eye movements, initial analyses showed that higher cue fluency was related to both higher FOKs and higher RCJs. However, further analyses revealed that the effects of the scene cue on RCJs were mediated by FOKs. Turning to the target, increased viewing time and faster viewing of the correct associate related to higher FOKs, consistent with the idea that target accessibility is a basis of FOKs. In contrast, the amount of viewing directed to the chosen face, regardless of whether it was correct, predicted higher RCJs, suggesting that choice experience is a significant contributor RCJs. We also examined covariates of the change in RCJ rating from the FOK rating, and showed that increased and faster viewing of the chosen face predicted raising one's confidence above one's FOK. Taken together these results suggest that metamemory judgments should not be thought of only as distinct subjective experiences, but complex processes that interact and evolve as new psychological bases for subjective experience become available.

  5. Dysregulated responses to emotions among abstinent heroin users: correlation with childhood neglect and addiction severity.

    PubMed

    Gerra, G; Somaini, L; Manfredini, M; Raggi, M A; Saracino, M A; Amore, M; Leonardi, C; Cortese, E; Donnini, C

    2014-01-03

    The aim of this paper was to investigate the subjective responses of abstinent heroin users to both neutral and negative stimuli and the related hypothalamus-pituitary-adrenal reactions to emotional experience in relationship to their perception of childhood adverse experiences. Thirty male abstinent heroin dependents were included in the study. Emotional responses and childhood neglect perception were measured utilizing the State-Trait Anxiety Inventory Y-1 and the Child Experience of Care and Abuse Questionnaire. Neutral and unpleasant pictures selected from the International Affective Picture System and the Self-Assessment Manikin procedure have been used to determine ratings of pleasure and arousal. These ratings were compared with normative values obtained from healthy volunteers used as control. Blood samples were collected before and after the experimental sessions to determine both adrenocorticotropic hormone and cortisol plasma levels. Basal anxiety scores, cortisol and adrenocorticotropic hormone levels were higher in abstinent heroin users than in controls. Tests showed that anxiety scores did not change in controls after the vision of neutral slides, whilst they did in abstinent heroin addicts, increasing significantly; and increased less significantly after the unpleasant task, in comparison to controls. Abstinent heroin users showed significantly higher levels of parent antipathy and childhood emotional neglect perception than controls for both the father and the mother. Plasma adrenocorticotropic hormone and cortisol levels did not significantly increase after unpleasant slide set viewing among addicted individuals, because of the significantly higher basal levels characterizing the addicted subjects in comparison with controls. Multiple regression correlation showed a significant relationship between childhood neglect perception, arousal reaction, impaired hypothalamus-pituitary-adrenal axis response and addiction severity. Early adverse experiences seem to affect the entire interaction between hyper-arousal, reduced hormonal response to stress and addiction severity. Our findings, although obtained in a small number of subjects, indicate a significant link between the perception of parental style/care/support during childhood and the ability to cope with stressful emotional stimuli in adulthood and addiction severity. © 2013.

  6. Purchases of food in youth. Influence of price and income.

    PubMed

    Epstein, Leonard H; Handley, Elizabeth A; Dearing, Kelly K; Cho, David D; Roemmich, James N; Paluch, Rocco A; Raja, Samina; Pak, Youngju; Spring, Bonnie

    2006-01-01

    One way to increase choice of healthy over unhealthy behaviors is to increase the cost of less healthy alternatives or reduce the cost of healthier alternatives. The influence of price on purchases of healthy and unhealthy foods was evaluated in two laboratory experiments. In Experiment 1, thirty-two 10- to 12-year-old youth were given $5.00 and allowed to purchase multiple portions of a healthy food (fruit or vegetable) and a less healthy food (higher-fat snack). The price of one type of food varied from $0.50 to $2.50, while the price of the other type was held at $1.00. Increasing the price of a type of food reduced purchases of that type of food, but did not lead to substitution with the alternative type of food. In Experiment 2, twenty 10- to 14-year-old youth were given $1.00, $3.00, and $5.00 to purchase healthy and unhealthy foods. The price of each food was raised and lowered by 25% and 50%. Raising the price of healthy or unhealthy foods resulted in decreased purchases of those foods, and income available interacted with price to predict the pattern of substitution of alternative foods. These results show the potential for controlled laboratory studies of price and food purchases, and show that the substitution of healthier for unhealthy food is related to available money.

  7. The Study of Micro-Pressure Inner-Loop Bioreactor Oxygen Mass Transfer Characteristics

    NASA Astrophysics Data System (ADS)

    Wan, L. G.; Lin, Q.; Bian, D. J.; Ren, Q. K.; Xiao, Y. B.; Lu, W. X.

    2018-03-01

    The oxygen mass transfer characteristics in a Micro-Pressure Inner-Loop bioreactor (MPR) were studied by clean water oxygenation experiment, the results show that when the aeration adopt by 0.1, 0.2, 0.4, 0.6 m3·h-1, respectively, the oxygen mass transfer coefficient KLa(20) in the reactor increases with the increase of the aeration. KLa(20) shows a good linear correlation with the aeration. The rate is 0.2128 h·m-3·min-1 and the correlation coefficient R=0.993. However, the trend of EO2 increases first and then decreases with the increase of aeration. When the aeration increased to 0.4 m3·h-1, the EO2 reaches the maximum. If aeration increases constantly, EO2 begin to decrease excessive aeration may lead to an increase in energy waste during reactor operation.

  8. Experience moderates overlap between object and face recognition, suggesting a common ability

    PubMed Central

    Gauthier, Isabel; McGugin, Rankin W.; Richler, Jennifer J.; Herzmann, Grit; Speegle, Magen; Van Gulick, Ana E.

    2014-01-01

    Some research finds that face recognition is largely independent from the recognition of other objects; a specialized and innate ability to recognize faces could therefore have little or nothing to do with our ability to recognize objects. We propose a new framework in which recognition performance for any category is the product of domain-general ability and category-specific experience. In Experiment 1, we show that the overlap between face and object recognition depends on experience with objects. In 256 subjects we measured face recognition, object recognition for eight categories, and self-reported experience with these categories. Experience predicted neither face recognition nor object recognition but moderated their relationship: Face recognition performance is increasingly similar to object recognition performance with increasing object experience. If a subject has a lot of experience with objects and is found to perform poorly, they also prove to have a low ability with faces. In a follow-up survey, we explored the dimensions of experience with objects that may have contributed to self-reported experience in Experiment 1. Different dimensions of experience appear to be more salient for different categories, with general self-reports of expertise reflecting judgments of verbal knowledge about a category more than judgments of visual performance. The complexity of experience and current limitations in its measurement support the importance of aggregating across multiple categories. Our findings imply that both face and object recognition are supported by a common, domain-general ability expressed through experience with a category and best measured when accounting for experience. PMID:24993021

  9. Experience moderates overlap between object and face recognition, suggesting a common ability.

    PubMed

    Gauthier, Isabel; McGugin, Rankin W; Richler, Jennifer J; Herzmann, Grit; Speegle, Magen; Van Gulick, Ana E

    2014-07-03

    Some research finds that face recognition is largely independent from the recognition of other objects; a specialized and innate ability to recognize faces could therefore have little or nothing to do with our ability to recognize objects. We propose a new framework in which recognition performance for any category is the product of domain-general ability and category-specific experience. In Experiment 1, we show that the overlap between face and object recognition depends on experience with objects. In 256 subjects we measured face recognition, object recognition for eight categories, and self-reported experience with these categories. Experience predicted neither face recognition nor object recognition but moderated their relationship: Face recognition performance is increasingly similar to object recognition performance with increasing object experience. If a subject has a lot of experience with objects and is found to perform poorly, they also prove to have a low ability with faces. In a follow-up survey, we explored the dimensions of experience with objects that may have contributed to self-reported experience in Experiment 1. Different dimensions of experience appear to be more salient for different categories, with general self-reports of expertise reflecting judgments of verbal knowledge about a category more than judgments of visual performance. The complexity of experience and current limitations in its measurement support the importance of aggregating across multiple categories. Our findings imply that both face and object recognition are supported by a common, domain-general ability expressed through experience with a category and best measured when accounting for experience. © 2014 ARVO.

  10. Study on Adsorption of Chromium (VI) by Activated Carbon from Cassava Sludge

    NASA Astrophysics Data System (ADS)

    Yang, Jinhui; Li, Chuanshu; Yang, Bin; Kang, Sijun; Zhang, Zhen

    2018-03-01

    In this paper, a new type of adsorbent prepared by waste sludge from alcohol production industry was used to adsorb Cr (VI) in activated carbon from cassava sludge. A series of static adsorption experiments were carried out on the initial concentration of solution Cr (VI), pH value of solution, adsorption time and dosage of adsorbent. The results of single factor experiments show that the removal rate of Cr (VI) increases with the initial concentration of Cr(VI), while the adsorption amount is opposite. When the pH value of the solution is low, the adsorption effect of activated carbon is better.The adsorption time should be controlled within 40-60min. When the activated carbon dosage is increased, the removal rate increases but the adsorption capacity decreases.

  11. Sociology: Drivers of climate change beliefs

    NASA Astrophysics Data System (ADS)

    Givens, Jennifer E.

    2014-12-01

    Direct experience of global warming is expected to increase the number of people who accept that it is real and human-caused. A study now shows that people's perceptions about abnormal temperatures mostly match actual measurements but do not affect climate change beliefs.

  12. Effects of air pollutants on lemons and naval oranges

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

    Thompson, C.R.

    1968-01-01

    The effects of photochemical oxidant and fluoride air pollutants on lemon and orange trees were evaluated in a series of greenhouse experiments. Trees exposed to the pollutants show increased lead drop and decreased fruit yield in comparison to controls.

  13. High body mass index is associated with impaired cognitive control.

    PubMed

    Sellaro, Roberta; Colzato, Lorenza S

    2017-06-01

    The prevalence of weight problems is increasing worldwide. There is growing evidence that high body mass index (BMI) is associated with frontal lobe dysfunction and cognitive deficits concerning mental flexibility and inhibitory control efficiency. The present study aims at replicating and extending these observations. We compared cognitive control performance of normal weight (BMI < 25) and overweight (BMI ≥ 25) university students on a task tapping either inhibitory control (Experiment 1) or interference control (Experiment 2). Experiment 1 replicated previous findings that found less efficient inhibitory control in overweight individuals. Experiment 2 complemented these findings by showing that cognitive control impairments associated with high BMI also extend to the ability to resolve stimulus-induced response conflict and to engage in conflict-driven control adaptation. The present results are consistent with and extend previous literature showing that high BMI in young, otherwise healthy individuals is associated with less efficient cognitive control functioning. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Mariner Venus Mercury 1973 S/X-band experiment

    NASA Technical Reports Server (NTRS)

    Levy, G. S.

    1977-01-01

    The S/X-band experiment on the Mariner Venus/Mercury 1973 spacecraft constituted a unique opportunity to demonstrate the capability of an X-band downlink coherent with the normal S-band downlink. This was both a technological and scientific experiment, and the results indicated that it was successful in both cases. Analysis of the tracking data shows that the new S/X data type was capable of reducing the miss distance at the planet Mercury by 80% (post-processed data). The use of S/X electron content was demonstrated by comparison with Faraday rotation data. An X-band turnaround telemetry experiment showed the feasibility of a planetary X-band link. In the science area, the model atmospheric environment of Venus was refined. The ionosphere of the planet was measured to a higher accuracy than before, and the value of the dual-frequency link for measuring the scale size of turbulence was demonstrated. The estimate of the scale size was increased from 100 m to above 5 km.

  15. Audio-visual speech experience with age influences perceived audio-visual asynchrony in speech.

    PubMed

    Alm, Magnus; Behne, Dawn

    2013-10-01

    Previous research indicates that perception of audio-visual (AV) synchrony changes in adulthood. Possible explanations for these age differences include a decline in hearing acuity, a decline in cognitive processing speed, and increased experience with AV binding. The current study aims to isolate the effect of AV experience by comparing synchrony judgments from 20 young adults (20 to 30 yrs) and 20 normal-hearing middle-aged adults (50 to 60 yrs), an age range for which a decline of cognitive processing speed is expected to be minimal. When presented with AV stop consonant syllables with asynchronies ranging from 440 ms audio-lead to 440 ms visual-lead, middle-aged adults showed significantly less tolerance for audio-lead than young adults. Middle-aged adults also showed a greater shift in their point of subjective simultaneity than young adults. Natural audio-lead asynchronies are arguably more predictable than natural visual-lead asynchronies, and this predictability may render audio-lead thresholds more prone to experience-related fine-tuning.

  16. Active elimination of radio frequency interference for improved signal-to-noise ratio for in-situ NMR experiments in strong magnetic field gradients

    NASA Astrophysics Data System (ADS)

    Ibrahim, M.; Pardi, C. I.; Brown, T. W. C.; McDonald, P. J.

    2018-02-01

    Improvement in the signal-to-noise ratio of Nuclear Magnetic Resonance (NMR) systems may be achieved either by increasing the signal amplitude or by decreasing the noise. The noise has multiple origins - not all of which are strictly "noise": incoherent thermal noise originating in the probe and pre-amplifiers, probe ring down or acoustic noise and coherent externally broadcast radio frequency transmissions. The last cannot always be shielded in open access experiments. In this paper, we show that pulsed, low radio-frequency data communications are a significant source of broadcast interference. We explore two signal processing methods of de-noising short T2∗ NMR experiments corrupted by these communications: Linear Predictive Coding (LPC) and the Discrete Wavelet Transform (DWT). Results are shown for numerical simulations and experiments conducted under controlled conditions with pseudo radio frequency interference. We show that both the LPC and DWT methods have merit.

  17. Evaluation of pretreatment methods on mixed inoculum for both batch and continuous thermophilic biohydrogen production from cassava stillage.

    PubMed

    Luo, Gang; Xie, Li; Zou, Zhonghai; Wang, Wen; Zhou, Qi

    2010-02-01

    Anaerobic sludges, pretreated by chloroform, base, acid, heat and loading-shock, as well as untreated sludge were evaluated for their thermophilic fermentative hydrogen-producing characters from cassava stillage in both batch and continuous experiments. Results showed that the highest hydrogen production was obtained by untreated sludge and there were significant differences (p<0.05) in hydrogen yields (varied from 32.9 to 65.3mlH(2)/gVS) among the tested pretreatment methods in batch experiments. However, the differences in hydrogen yields disappeared in continuous experiments, which indicated the pretreatment methods had only short-term effects on the hydrogen production. Further study showed that alkalinity was a crucial parameter influencing the fermentation process. When the influent was adjusted to pH 6 by NaHCO(3) instead of NaOH, the hydrogen yield increased from about 40 to 52mlH(2)/gVS in all the experiments. Therefore, pretreatment of anaerobic sludge is unnecessary for practical thermophilic fermentative hydrogen production from cassava stillage.

  18. Multiplexed single-molecule force spectroscopy using a centrifuge.

    PubMed

    Yang, Darren; Ward, Andrew; Halvorsen, Ken; Wong, Wesley P

    2016-03-17

    We present a miniature centrifuge force microscope (CFM) that repurposes a benchtop centrifuge for high-throughput single-molecule experiments with high-resolution particle tracking, a large force range, temperature control and simple push-button operation. Incorporating DNA nanoswitches to enable repeated interrogation by force of single molecular pairs, we demonstrate increased throughput, reliability and the ability to characterize population heterogeneity. We perform spatiotemporally multiplexed experiments to collect 1,863 bond rupture statistics from 538 traceable molecular pairs in a single experiment, and show that 2 populations of DNA zippers can be distinguished using per-molecule statistics to reduce noise.

  19. Multiplexed single-molecule force spectroscopy using a centrifuge

    PubMed Central

    Yang, Darren; Ward, Andrew; Halvorsen, Ken; Wong, Wesley P.

    2016-01-01

    We present a miniature centrifuge force microscope (CFM) that repurposes a benchtop centrifuge for high-throughput single-molecule experiments with high-resolution particle tracking, a large force range, temperature control and simple push-button operation. Incorporating DNA nanoswitches to enable repeated interrogation by force of single molecular pairs, we demonstrate increased throughput, reliability and the ability to characterize population heterogeneity. We perform spatiotemporally multiplexed experiments to collect 1,863 bond rupture statistics from 538 traceable molecular pairs in a single experiment, and show that 2 populations of DNA zippers can be distinguished using per-molecule statistics to reduce noise. PMID:26984516

  20. Reinforcement Learning and Savings Behavior.

    PubMed

    Choi, James J; Laibson, David; Madrian, Brigitte C; Metrick, Andrew

    2009-12-01

    We show that individual investors over-extrapolate from their personal experience when making savings decisions. Investors who experience particularly rewarding outcomes from saving in their 401(k)-a high average and/or low variance return-increase their 401(k) savings rate more than investors who have less rewarding experiences with saving. This finding is not driven by aggregate time-series shocks, income effects, rational learning about investing skill, investor fixed effects, or time-varying investor-level heterogeneity that is correlated with portfolio allocations to stock, bond, and cash asset classes. We discuss implications for the equity premium puzzle and interventions aimed at improving household financial outcomes.

  1. Calculation of Energetic Ion Tail from Ion Cyclotron Resonance Frequency Heating

    NASA Astrophysics Data System (ADS)

    Wang, Jianguo; Li, Youyi; Li, Jiangang

    1994-04-01

    The second harmonic frequency of hydrogen ion cyclotron resonance heating experiment on HT-6M tokamak was studied by adding the quasi-linear wave-ion interaction term in the two-dimensional (velocity space), time-dependent, nonlinear and multispecies Fokker-Planck equation. The temporal evolution of ion distribution function and relevant parameters were calculated and compared with experiment data. The calculation shows that the ion temperature increases, high-energy ion tail (above 5 keV) and anisotropy appear when the wave is injected to plasma. The simulations are in reasonable agreement with experiment data.

  2. Exploring the Mechanisms of Exercise-Induced Hypoalgesia Using Somatosensory and Laser Evoked Potentials.

    PubMed

    Jones, Matthew D; Taylor, Janet L; Booth, John; Barry, Benjamin K

    2016-01-01

    Exercise-induced hypoalgesia is well described, but the underlying mechanisms are unclear. The aim of this study was to examine the effect of exercise on somatosensory evoked potentials, laser evoked potentials, pressure pain thresholds and heat pain thresholds. These were recorded before and after 3-min of isometric elbow flexion exercise at 40% of the participant's maximal voluntary force, or an equivalent period of rest. Exercise-induced hypoalgesia was confirmed in two experiments (Experiment 1-SEPs; Experiment 2-LEPs) by increased pressure pain thresholds at biceps brachii (24.3 and 20.6% increase in Experiment 1 and 2, respectively; both d > 0.84 and p < 0.001) and first dorsal interosseous (18.8 and 21.5% increase in Experiment 1 and 2, respectively; both d > 0.57 and p < 0.001). In contrast, heat pain thresholds were not significantly different after exercise (forearm: 10.8% increase, d = 0.35, p = 0.10; hand: 3.6% increase, d = 0.06, p = 0.74). Contrasting effects of exercise on the amplitude of laser evoked potentials (14.6% decrease, d = -0.42, p = 0.004) and somatosensory evoked potentials (10.9% increase, d = -0.02, p = 1) were also observed, while an equivalent period of rest showed similar habituation (laser evoked potential: 7.3% decrease, d = -0.25, p = 0.14; somatosensory evoked potential: 20.7% decrease, d = -0.32, p = 0.006). The differential response of pressure pain thresholds and heat pain thresholds to exercise is consistent with relative insensitivity of thermal nociception to the acute hypoalgesic effects of exercise. Conflicting effects of exercise on somatosensory evoked potentials and laser evoked potentials were observed. This may reflect non-nociceptive contributions to the somatosensory evoked potential, but could also indicate that peripheral nociceptors contribute to exercise-induced hypoalgesia.

  3. Retrieval attempts enhance learning regardless of time spent trying to retrieve.

    PubMed

    Vaughn, Kalif E; Hausman, Hannah; Kornell, Nate

    2017-03-01

    Attempting to retrieve information from memory is an engaging cognitive activity. We predicted that people would learn more when they had spent more time attempting to retrieve. In experiments 1a and 1b, participants were shown trivia questions for 0, 5, 10, or 30 seconds and then the answer was revealed. They took a final test immediately or after 48 hours. Retrieval enhanced learning, but the length of the retrieval attempt had no effect (i.e., final test performance was equivalent in the 5-, 10-, and 30-second conditions and worse in the 0-second condition). During the initial retrieval attempt, more time did increase recall, suggesting that participants continued to engage in productive retrieval activities when given more time. Showing the answer for longer (7 versus 2 seconds) increased learning in Experiments 2a and 2b. Experiment 3 examined the effect of retrieval success and Experiment 4 replicated the results using different materials. These results have direct implications for current theories of retrieval.

  4. Is masked priming modulated by memory load? A test of the automaticity of masked identity priming in lexical decision.

    PubMed

    Perea, Manuel; Marcet, Ana; Lozano, Mario; Gomez, Pablo

    2018-05-29

    One of the key assumptions of the masked priming lexical decision task (LDT) is that primes are processed without requiring attentional resources. Here, we tested this assumption by presenting a dual-task manipulation to increase memory load and measure the change in masked identity priming on the targets in the LDT. If masked priming does not require attentional resources, increased memory load should have no influence on the magnitude of the observed identity priming effects. We conducted two LDT experiments, using a within-subjects design, to investigate the effect of memory load (via a concurrent matching task Experiment 1 and a concurrent search task in Experiment 2) on masked identity priming. Results showed that the magnitude of masked identity priming on word targets was remarkably similar under high and low memory load. Thus, these experiments provide empirical evidence for the automaticity assumption of masked identity priming in the LDT.

  5. Retention, Incentives, and DoD Experience Under the 40-Year Military Pay Table

    DTIC Science & Technology

    2016-01-01

    year table, effective April 2007, added longevity increases after YOS 26 for officers in O-6 and above, warrant officers in W- 4 and W-5, and enlisted...realized basic pay increases after YOS 30, while both O-8s and O-9s received pay increases after YOS 28. Figure 2.2 shows basic pay for officers in O- 4 ...8 2.2. Basic Pay, Officers, O- 4 to O-6

  6. Seeing the big picture: Broadening attention relieves sadness and depressed mood.

    PubMed

    Gu, Li; Yang, Xueling; Li, Liman Man Wai; Zhou, Xinyue; Gao, Ding-Guo

    2017-08-01

    We examined whether the broadened attentional scope would affect people's sad or depressed mood with two experiments, enlightened by the meaning of "seeing the big picture" and the broaden-and-build model. Experiment 1 (n = 164) is a laboratory-based experiment, in which we manipulated the attentional scope by showing participants zoomed-out or zoomed-in scenes. In Experiment 2 (n = 44), we studied how depressed mood and positive and negative emotions were affected when participants watched distant versus proximal scenes for eight weeks in real life. Healthy participants in Experiment 1, who were induced to feel sad, could return to the baseline mood after having the broadened attention task but not after having the narrowed attention task, which indicated that immediate attention broadening manipulation could function as antidotes for the lingering effects of induced negative emotions. Participants with depressed mood in Experiment 2 showed reduced depressed mood, increased positive affect, and decreased negative affect after receiving attention broadening training compared to those receiving attention narrowing training. Our findings suggest a robust role of broadened attentional scope in relieving negative emotions and even mildly depressed mood in the long run. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  7. A cocktail-party listening experiment with children

    NASA Astrophysics Data System (ADS)

    Wightman, Frederic; Callahan, Michael; Kistler, Doris

    2003-04-01

    In an experiment modeled after one reported recently by Brungart and Simpson [J. Acoust. Soc. Am. 112, 2985-2995 (2002)], 38 children (ages 4-16) and 10 adults responded to a monaural target speech signal in the presence of one or two distracter speech signals. The target speaker was a male and the distracter speakers were females. When two distracters were present they were in different ears. Performance at several different target ear S/N was measured and psychometric functions were fitted to estimate threshold, or the 50% performance level. The youngest children required approximately 20 dB higher S/N than adults to achieve threshold with a single distracter. This difference disappeared by age 16. The impact of adding the contralateral distracter, which is thought to contribute only informational masking, was roughly constant across age, however. Adult thresholds increased about 11 dB and the thresholds for the youngest children increased about 10 dB. This was surprising given previous experiments that showed much larger informational masking effects in young children. Also inconsistent with previous results is the lack of individual differences. Nearly all listeners showed almost the same contralateral distracter effect. [Work supported by NICHD.

  8. Image analysis of single event transient effects on charge coupled devices irradiated by protons

    NASA Astrophysics Data System (ADS)

    Wang, Zujun; Xue, Yuanyuan; Liu, Jing; He, Baoping; Yao, Zhibin; Ma, Wuying

    2016-10-01

    The experiments of single event transient (SET) effects on charge coupled devices (CCDs) irradiated by protons are presented. The radiation experiments have been carried out at the accelerator protons with the energy of 200 MeV and 60 MeV.The incident angles of the protons are at 30°and 90° to the plane of the CCDs to obtain the images induced by the perpendicularity and incline incident angles. The experimental results show that the typical characteristics of the SET effects on a CCD induced by protons are the generation of a large number of dark signal spikes (hot pixels) which are randomly distributed in the "pepper" images. The characteristics of SET effects are investigated by observing the same imaging area at different time during proton radiation to verify the transient effects. The experiment results also show that the number of dark signal spikes increases with increasing integration time during proton radiation. The CCDs were tested at on-line and off-line to distinguish the radiation damage induced by the SET effects or DD effects. The mechanisms of the dark signal spike generation induced by the SET effects and the DD effects are demonstrated respectively.

  9. Revisiting the rise and fall of false recall: presentation rate effects depend on retention interval.

    PubMed

    Smith, Troy A; Kimball, Daniel R

    2012-01-01

    Leading theories of false memory predict that veridical and false recall of lists of semantically associated words can be dissociated by varying the presentation speed during study. Specifically, as presentation rate increases from milliseconds to seconds, veridical recall is predicted to increase monotonically while false recall is predicted to show a rapid rise and then a slow decrease--a pattern shown by McDermott and Watson (2001) in a study using immediate recall tests. In three experiments we tested the generality of the effects of rapid presentation rates on veridical and false memory. In Experiments 1 and 2 participants exhibited high levels of false recall on a delayed recall test, even for very fast stimulus onset asynchronies (SOA)--contrary to predictions from leading theories of false memory. When we switched to an immediate recall test in Experiment 3 we replicated the pattern predicted by the theories and observed by McDermott and Watson. Follow-up analyses further showed that the relative output position of false recalls is not affected by presentation rate, contrary to predictions from fuzzy trace theory. Implications for theories of false memory, including activation monitoring theory and fuzzy trace theory, are discussed.

  10. Selective incivility: immigrant groups experience subtle workplace discrimination at different rates.

    PubMed

    Krings, Franciska; Johnston, Claire; Binggeli, Steve; Maggiori, Christian

    2014-10-01

    Immigrants play an increasingly important role in local labor markets. Not only do they grow steadily in number but also in cultural, educational, and skill diversity, underlining the necessity to distinguish between immigrant groups when studying discrimination against immigrants. We examined immigrant employees' subtle discrimination experiences in a representative sample in Switzerland, controlling for dispositional influences. Results showed that mainly members of highly competitive immigrant groups, from immediate neighbor countries, experienced workplace incivility and that these incivility experiences were related to higher likelihoods of perceived discrimination at work. This research confirms recent accounts that successful but disliked groups are particularly likely to experience subtle interpersonal discrimination. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  11. Experiment on search for neutron-antineutron oscillations using a projected UCN source at the WWR-M reactor

    NASA Astrophysics Data System (ADS)

    Fomin, A. K.; Serebrov, A. P.; Zherebtsov, O. M.; Leonova, E. N.; Chaikovskii, M. E.

    2017-01-01

    We propose an experiment on search for neutron-antineutron oscillations based on the storage of ultracold neutrons (UCN) in a material trap. The sensitivity of the experiment mostly depends on the trap size and the amount of UCN in it. In Petersburg Nuclear Physics Institute (PNPI) a high-intensity UCN source is projected at the WWR-M reactor, which must provide UCN density 2-3 orders of magnitude higher than existing sources. The results of simulations of the designed experimental scheme show that the sensitivity can be increased by ˜ 10-40 times compared to sensitivity of previous experiment depending on the model of neutron reflection from walls.

  12. The Greenland Ice Sheet's surface mass balance in a seasonally sea ice-free Arctic

    NASA Astrophysics Data System (ADS)

    Day, J. J.; Bamber, J. L.; Valdes, P. J.

    2013-09-01

    General circulation models predict a rapid decrease in sea ice extent with concurrent increases in near-surface air temperature and precipitation in the Arctic over the 21st century. This has led to suggestions that some Arctic land ice masses may experience an increase in accumulation due to enhanced evaporation from a seasonally sea ice-free Arctic Ocean. To investigate the impact of this phenomenon on Greenland Ice Sheet climate and surface mass balance (SMB), a regional climate model, HadRM3, was used to force an insolation-temperature melt SMB model. A set of experiments designed to investigate the role of sea ice independently from sea surface temperature (SST) forcing are described. In the warmer and wetter SI + SST simulation, Greenland experiences a 23% increase in winter SMB but 65% reduced summer SMB, resulting in a net decrease in the annual value. This study shows that sea ice decline contributes to the increased winter balance, causing 25% of the increase in winter accumulation; this is largest in eastern Greenland as the result of increased evaporation in the Greenland Sea. These results indicate that the seasonal cycle of Greenland's SMB will increase dramatically as global temperatures increase, with the largest changes in temperature and precipitation occurring in winter. This demonstrates that the accurate prediction of changes in sea ice cover is important for predicting Greenland SMB and ice sheet evolution.

  13. Reversing the mere exposure effect in spider fearfuls: Preliminary evidence of sensitization.

    PubMed

    Becker, Eni S; Rinck, Mike

    2016-12-01

    A mere exposure effect (MEE) is said to occur when individuals' liking of a suboptimally and repeatedly presented stimulus increases compared to never-presented stimuli, while they are unable to indicate which stimuli were previously presented and which were not. In two experiments, we used the MEE to study automatic evaluative processes in highly spider-fearful individuals (SFs). Pictures of spiders and butterflies were repeatedly presented suboptimally to SFs and to non-anxious controls (NACs). In Experiment 1, both groups showed the MEE for butterflies, preferring previously presented butterfly pictures over new ones. For spider pictures, only NACs showed an MEE, whereas SFs showed no preference. Experiment 2 involved a more unpleasant presentation situation, because for each picture, participants had the difficult task to indicate what had been presented to them. This led to a reversed MEE for spiders in SFs: They preferred new spider pictures over previously presented ones. In both experiments, no evidence was observed for the ability to differentiate between old an new pictures. The results are tentatively explained within Zajonc' theory of the MEE, and they are related to the concept of sensitization in anxiety disorders. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Effect of diet change on the behavior of chicks of an egg-laying strain.

    PubMed

    Dixon, Greg; Green, Laura E; Nicol, Christine J

    2006-01-01

    Injurious pecking has serious welfare consequences in flocks of hens kept for egg laying, especially when loose-housed. Frequent diet change is a significant risk for injurious pecking; how the mechanics of diet change influence pecking behavior is unknown. This study investigated the effect of diet change on the behavior of chicks from a laying strain. The study included a 3-week familiarity phase: 18 chick pairs received unflavored feed (Experiment 1); 18 pairs received orange oil-flavored (Experiment 2). All chicks participated in a dietary preference test (P); a diet change (DC); or a control group (C), 6 scenarios. All P chicks preferred unflavored feed. In Experiment 1, DC involved change from unflavored to orange-flavored; Experiment 2, orange- flavored to unflavored. Compared with controls, Experiment 2 DC chicks exhibited few behavioral differences; Experiment 1 DC chicks exhibited increased behavioral event rates on Days 1 and 7. They pecked significantly longer at their environment; by Day 7, they showed significantly more beak activity. There was little evidence of dietary neophobia. Change from more preferred to less preferred feed led to increased activity and redirected pecking behavior.

  15. Study on structural characteristics of pillared clay modified phosphate fertilizers and its increase efficiency mechanism*

    PubMed Central

    Wu, Ping-xiao; Liao, Zong-wen

    2005-01-01

    Three types of new high-efficiency phosphate fertilizers were made when pillared clays at certain proportions were added into ground phosphate rock. Chemical analyses showed that their soluble phosphorus content decreased more than that of superphosphate. Pot experiment showed that, under equal weights, the new fertilizers increased their efficiency by a large margin over that of superphosphate. Researches on their structures by means of XRD, IR and EPR spectrum revealed that their crystal structures changed considerably, improving their activity and preventing the fixation of available phosphorus in the soil, and consequently, greatly improved the bioavailability and became the main cause of the increase of biomass. PMID:15682504

  16. A 10-Day Developmental Voyage: Converging Evidence from Three Studies Showing that Self-Esteem May Be Elevated and Maintained without Negative Outcomes

    ERIC Educational Resources Information Center

    Kafka, S.; Hunter, J. A.; Hayhurst, J.; Boyes, M.; Thomson, R. L.; Clarke, H.; Grocott, A. M.; Stringer, M.; O'Brien, K. S.

    2012-01-01

    Empirical evidence shows that educational experiences in the context of the outdoors lead to elevated self-esteem. Although elevated self-esteem is widely assumed to promote beneficial outcomes, recent evidence suggests that elevated self-esteem may also facilitate a variety of negative outcomes (i.e., increased prejudice, aggression, drug and…

  17. Hepatic betaine-homocysteine methyltransferase activity in the chicken is influenced by dietary intake of sulfur amino acids, choline and betaine.

    PubMed

    Emmert, J L; Garrow, T A; Baker, D H

    1996-08-01

    There is much interest in the metabolism of homocysteine, because elevated plasma homocysteine [hyperhomocyst(e)inemia] is an independent risk factor for the development of cardiovascular disease. Four chick assays were conducted to determine the effects of varying dietary sulfur amino acids, choline and betaine on the activity of hepatic betaine-homocysteine methyltransferase (BHMT), an enzyme likely to be important in modulating plasma homocysteine. In Experiment 1, chicks were fed a purified crystalline amino acid diet containing adequate sulfur amino acids and choline. Excess dietary methionine, or the combination of excess cystine with choline or betaine, caused a small increase (P < 0.05) in BHMT activity. In Experiment 2, use of a methionine-deficient purified diet resulted in a threefold increase (P < 0.05) in BHMT activity, and addition of choline or betaine further increased (P < 0.05) BHMT activity. In Experiment 3, use of a methionine-deficient corn-peanut meal diet increased BHMT (P < 0.05) relative to that of chicks supplemented with adequate methionine, and addition of surfeit choline to the methionine-deficient basal diet caused a further increase (P < 0.05). In Experiment 4, addition of both surfeit choline and surfeit betaine to the methionine-deficient corn-peanut meal diet caused an increase (P < 0.05) in BHMT activity relative to that observed in chicks fed the methionine-deficient basal diet. These assays show that large increases in BHMT activity can be produced under methionine-deficient conditions, especially in the presence of excess choline or betaine.

  18. Growth curves and age-related changes in carcass characteristics, organs, serum parameters, and intestinal transporter gene expression in domestic pigeon (Columba livia).

    PubMed

    Gao, C Q; Yang, J X; Chen, M X; Yan, H C; Wang, X Q

    2016-04-01

    Two experiments were conducted to fit growth curves, and determine age-related changes in carcass characteristics, organs, serum biochemical parameters, and gene expression of intestinal nutrient transporters in domestic pigeon (Columba livia). In experiment 1, body weight (BW) of 30 pigeons was respectively determined at 1, 3, 7, 14, 21, 28, and 35 days old to fit growth curves and to describe the growth of pigeons. In experiment 2, eighty-four 1-day-old squabs were grouped by weight into 7 groups. On d 1, 3, 7, 14, 21, 28, and 35, twelve birds from each group were randomly selected for slaughter and post-slaughter analysis. The results showed that BW of pigeons increased rapidly from d 1 to d 28 (a 25.7-fold increase), and then had little change until d 35. The Logistic, Gompertz, and Von Bertalanffy functions can all be well fitted with the growth curve of domestic pigeons (R2>0.90) and the Gompertz model showed the highest R2value among the models (R2=0.9997). The equation of Gompertz model was Y=507.72×e-(3.76exp(-0.17t))(Y=BW of pigeon (g); t=time (day)). In addition, breast meat yield (%) increased with age throughout the experiment, whereas the leg meat yield (%) reached to the peak on d 14. Serum total protein, albumin, globulin, and glucose concentration were increased with age, whereas serum uric acid concentration was decreased (P<0.05). Furthermore, the gene expressions of nutrient transporters (y+LAT2, LAT1, B0AT1, PepT1, and NHE2) in jejunum of pigeon were increased with age. The results of correlation analysis showed the gene expressions of B0AT1, PepT1, and NHE2 had positive correlations with BW (0.73

  19. Effect of Surface Tension Anisotropy and Welding Parameters on Initial Instability Dynamics During Solidification: A Phase-Field Study

    NASA Astrophysics Data System (ADS)

    Yu, Fengyi; Wei, Yanhong

    2018-05-01

    The effects of surface tension anisotropy and welding parameters on initial instability dynamics during gas tungsten arc welding of an Al-alloy are investigated by a quantitative phase-field model. The results show that the surface tension anisotropy and welding parameters affect the initial instability dynamics in different ways during welding. The surface tension anisotropy does not influence the solute diffusion process but does affect the stability of the solid/liquid interface during solidification. The welding parameters affect the initial instability dynamics by varying the growth rate and thermal gradient. The incubation time decreases, and the initial wavelength remains stable as the welding speed increases. When welding power increases, the incubation time increases and the initial wavelength slightly increases. Experiments were performed for the same set of welding parameters used in modeling, and the results of the experiments and simulations were in good agreement.

  20. Litterfall dynamics and nutrient decomposition of arid mangroves in the Gulf of California: Their role sustaining ecosystem heterotrophy

    NASA Astrophysics Data System (ADS)

    Sánchez-Andrés, R.; Sánchez-Carrillo, S.; Alatorre, L. C.; Cirujano, S.; Álvarez-Cobelas, M.

    2010-10-01

    This study shows results on litterfall dynamics and decay in mangrove stands of Avicennia germinans distributed along a latitudinal gradient (three forest sites) in the Gulf of California, in order to assess whether internal sources could support the observed mangrove ecosystem organic deficit in this arid tropic. Total mean annual litterfall production increased southward (712.6 ± 53.3, 1501.3 ± 145.1 and 1506.2 ± 280.5 g DW m -2 y -1, in the Yaqui, Mayo and Fuerte areas respectively), leaves being the main component of litter in all locations during the entire year, followed by fruits. The wet season (June-September) showed the highest litterfall rates through fruits. The temporal trend of litterfall production was significantly explained through mean air temperature ( R2 = 68%) whilst total annual litter production in the entire region showed a statistically significant relationship with total soil phosphorus, salinity, total nitrogen, organic matter and tree height ( R2 = 0.67). Throughout 117 days of the decomposition experiment, the litter lost 50% of its original dry weight in 5.8 days (average decay rate of 0.032 ± 0.04 g DW d -1) and there were not significant differences in the remaining mass after 6 days. The percentage of both C and P released from the litter correlated significantly with the ratio of tidal inundated days to total experiment days ( R2 = 0.62, p = 0.03 and R2 = 0.67, p = 0.02, respectively); however, the frequency of tidal inundation only showed a significant increase in C release from Avicennia litter after 6 and above 48 days of decomposition. Whereas the total C content of litter bags decreased linearly over the decomposition to (% Total C = 5.52 - 0.46 days, R2 = 0.81, p = 0.0005), N content displayed an irregular pattern with a significant increase of decay between 48 and 76 days from the beginning of the experiment. The pattern for relative P content of litter revealed reductions of up to 99% of the original (%tot- P = -9.77 to 1.004 days, R2 = 0.72, p = 0.01) although most of the P reduction occurred between 17 and 34 days after the experiment started. Soil N and P contents, which exhibited significant differences in the course of the decomposition experiment, appeared to show significant differences between sampling sites, although they were not related to tidal influence, nor by leaf and nutrient leaching. In a global basis, C/ N litter ratios decreased linearly ( C/ N = 32.86 - 0.1006 days, R2 = 0.62, p = 0.02), showing a strong and significant correlation with meteorological variables ( R2 = 0.99, p = 0.01). C/ P ratios of litter increased through an exponential function ( C/ P = 119.35e 0.04day, R2 = 0.89, p < 0.001). Changes in the remaining percentage of litter mass during the experiment were significantly correlated with soil C/ N ratio ( R2 = 0.56, p = 0.03) as well as with the soil C/ P ratio ( R2 = 0.98, p < 0.001). Our results of litter decomposition dynamics in this mangrove support the fact of null net primary productivity of the arid mangrove wetlands: fast litter decomposition compensates the ecosystem organic deficit in order to sustain the mangrove productivity. Litter decomposition plays a key role in the ecosystem metabolism in mangroves of arid tropics.

  1. Final Report “Physiological, demographic, competitive and biogeochemical controls on the response of California’s ecosystems to environmental change”

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

    Goulden, Michael L.

    2016-02-08

    The Loma Ridge Global Change Experiment is a large, well-replicated water and nitrogen input manipulation in the Santa Ana Mountain foothills that operated with DOE support from 2006 to 2015. The experiment considers the effects of increased and decreased water input and increased N input on two adjacent ecosystem types: California Annual Grassland (GL), which is dominated by exotic, Eurasian grasses and forbs, and Coastal Sage Shrubland (CSS), which is dominated by native, drought deciduous, perennial shrubs. The experiment proceeded in two phases: "Phase I Severe treatment", and "Phase II Return to ambient". Phase I showed very rapid change inmore » species composition or ANPP with altered water or N input (low resistance), whereas Phase II showed a very rapid return to initial conditions once ambient water or N input were restored (high resilience). The severe drought treatment killed most of the shrubs in the dry plots and opened the canopy to herbaceous species, but this damage was ephemeral, and the shrubland community is recovering through the mechanisms and patterns that more typically mediate recovery from crown fire. The pattern of low resistance and high resilience carries implications for other "global change experiments", which have often also seen large and rapid treatment effects (low resistance), but have less frequently considered the subsequent recovery or resilience of the system.« less

  2. Daily Stressors as Antecedents, Correlates, and Consequences of Alcohol and Drug Use and Cravings in Community-Based Offenders

    PubMed Central

    Neupert, Shevaun D.; Desmarais, Sarah L.; Gray, Julie S.; Cohn, Amy M.; Doherty, Stephen; Knight, Kevin

    2017-01-01

    Justice-involved individuals with alcohol and drug use problems reoffend at higher rates than their non-using counterparts, with alcohol and drug use serving as an important vector to recidivism. At the daily level, exposure to stressors may exacerbate problematic alcohol and drug use; at the individual-level, prior treatment experiences may mitigate substance use as individuals adapt to and learn new coping mechanisms. We conducted a daily diary study using Interactive Voice Response (IVR) technology over 14 consecutive days with 117 men on probation or parole participating in a community-based treatment program (n = 860 calls) and referred to medication-assisted treatment. Participants reported daily stressors, craving for alcohol and illegal drugs, and use of alcohol and illegal drugs one time each day. Results of multilevel models showed significant day-to-day fluctuation in alcohol and drug craving and use. In concurrent models, increases in daily stressors were associated with increases in cravings and use of illegal drugs. Prior treatment experience modified many of these relationships, and additional lagged models revealed that those with less treatment experience reported an increase in next-day alcohol craving when they experienced increases in stressors on the previous day compared to those with more treatment experience. Collectively, these findings highlight the importance of tailoring treatment as a function of individual differences, including prior treatment experiences, and targeting daily stressors and subsequent cravings among justice-involved adults with alcohol and drug use problems. PMID:28383933

  3. The effects of whole grains on nutrient digestibilities, growth performance, and cecal short-chain fatty acid concentrations in young chicks fed ground corn-soybean meal diets.

    PubMed

    Biggs, P; Parsons, C M

    2009-09-01

    Five experiments were conducted to evaluate the effects of whole wheat, whole sorghum, or whole barley on nutrient digestibility, growth performance, and cecal short-chain fatty acid concentrations when supplemented primarily at the expense of corn in ground corn-soybean meal control diets. The first 4 experiments utilized New Hampshire x Columbian male chicks. In the first 2 experiments, feeding 5, 10, 15, or 20% whole wheat had no effect on growth performance at 21 d when compared with chicks fed the control diet. The third experiment tested 20, 35, and 50% whole wheat fed from 0 to 21 d of age and showed that a 50% whole wheat diet decreased (P<0.05) 21-d growth and feed efficiency when compared with chicks fed the control diet. In experiment 4, 10 and 20% whole sorghum reduced (P<0.05) growth at 21 d, whereas chicks fed 10 and 20% whole barley had similar weight gains to chicks fed a ground corn-soybean meal diet. The fifth experiment with commercial Ross x Ross male broiler chicks evaluated 10 and 20% whole sorghum or whole barley and 20 and 35% whole wheat. Growth at 21 d was unaffected by any dietary treatment. Feed efficiency was decreased (P<0.05) at 21 d with 20% whole wheat and improved (P<0.05) with 10% whole barley. Feeding whole grains to chicks resulted in an increase in gizzard weight, even as early as 7 d, in all experiments. Chicks fed diets containing 10 to 20% whole wheat generally had increased MEn values at 3 to 4, 7, 14, and 21 d and also had increased amino acid digestibility at 21 d in one experiment. At 21 d, cecal pH and short-chain fatty acid concentrations in all experiments were unaffected by feeding whole grains to chicks. The results of this study indicated that feeding whole wheat, sorghum, or barley increased gizzard weight, and feeding 10 to 20% whole wheat may increase ME and amino acid digestibility.

  4. Prefrontal Cortex Activation and Young Driver Behaviour: A fNIRS Study

    PubMed Central

    Foy, Hannah J.; Runham, Patrick; Chapman, Peter

    2016-01-01

    Road traffic accidents consistently show a significant over-representation for young, novice and particularly male drivers. This research examines the prefrontal cortex activation of young drivers and the changes in activation associated with manipulations of mental workload and inhibitory control. It also considers the explanation that a lack of prefrontal cortex maturation is a contributing factor to the higher accident risk in this young driver population. The prefrontal cortex is associated with a number of factors including mental workload and inhibitory control, both of which are also related to road traffic accidents. This experiment used functional near infrared spectroscopy to measure prefrontal cortex activity during five simulated driving tasks: one following task and four overtaking tasks at varying traffic densities which aimed to dissociate workload and inhibitory control. Age, experience and gender were controlled for throughout the experiment. The results showed that younger drivers had reduced prefrontal cortex activity compared to older drivers. When both mental workload and inhibitory control increased prefrontal cortex activity also increased, however when inhibitory control alone increased there were no changes in activity. Along with an increase in activity during overtaking manoeuvres, these results suggest that prefrontal cortex activation is more indicative of workload in the current task. There were no differences in the number of overtakes completed by younger and older drivers but males overtook significantly more than females. We conclude that prefrontal cortex activity is associated with the mental workload required for overtaking. We additionally suggest that the reduced activation in younger drivers may be related to a lack of prefrontal maturation which could contribute to the increased crash risk seen in this population. PMID:27227990

  5. Vicariously touching products through observing others' hand actions increases purchasing intention, and the effect of visual perspective in this process: An fMRI study.

    PubMed

    Liu, Yi; Zang, Xuelian; Chen, Lihan; Assumpção, Leonardo; Li, Hong

    2018-01-01

    The growth of online shopping increases consumers' dependence on vicarious sensory experiences, such as observing others touching products in commercials. However, empirical evidence on whether observing others' sensory experiences increases purchasing intention is still scarce. In the present study, participants observed others interacting with products in the first- or third-person perspective in video clips, and their neural responses were measured with functional magnetic resonance imaging (fMRI). We investigated (1) whether and how vicariously touching certain products affected purchasing intention, and the neural correlates of this process; and (2) how visual perspective interacts with vicarious tactility. Vicarious tactile experiences were manipulated by hand actions touching or not touching the products, while the visual perspective was manipulated by showing the hand actions either in first- or third-person perspective. During the fMRI scanning, participants watched the video clips and rated their purchasing intention for each product. The results showed that, observing others touching (vs. not touching) the products increased purchasing intention, with vicarious neural responses found in mirror neuron systems (MNS) and lateral occipital complex (LOC). Moreover, the stronger neural activities in MNS was associated with higher purchasing intention. The effects of visual perspectives were found in left superior parietal lobule (SPL), while the interaction of tactility and visual perspective was shown in precuneus and precuneus-LOC connectivity. The present study provides the first evidence that vicariously touching a given product increased purchasing intention and the neural activities in bilateral MNS, LOC, left SPL and precuneus are involved in this process. Hum Brain Mapp 39:332-343, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  6. Eutrophication and macroalgal blooms in temperate and tropical coastal waters: nutrient enrichment experiments with Ulva spp.

    PubMed Central

    Teichberg, Mirta; Fox, Sophia E; Olsen, Ylva S; Valiela, Ivan; Martinetto, Paulina; Iribarne, Oscar; Muto, Elizabeti Yuriko; Petti, Monica A V; Corbisier, Thaïs N; Soto-Jiménez, Martín; Páez-Osuna, Federico; Castro, Paula; Freitas, Helena; Zitelli, Andreina; Cardinaletti, Massimo; Tagliapietra, Davide

    2010-01-01

    Receiving coastal waters and estuaries are among the most nutrient-enriched environments on earth, and one of the symptoms of the resulting eutrophication is the proliferation of opportunistic, fast-growing marine seaweeds. Here, we used a widespread macroalga often involved in blooms, Ulva spp., to investigate how supply of nitrogen (N) and phosphorus (P), the two main potential growth-limiting nutrients, influence macroalgal growth in temperate and tropical coastal waters ranging from low- to high-nutrient supplies. We carried out N and P enrichment field experiments on Ulva spp. in seven coastal systems, with one of these systems represented by three different subestuaries, for a total of nine sites. We showed that rate of growth of Ulva spp. was directly correlated to annual dissolved inorganic nitrogen (DIN) concentrations, where growth increased with increasing DIN concentration. Internal N pools of macroalgal fronds were also linked to increased DIN supply, and algal growth rates were tightly coupled to these internal N pools. The increases in DIN appeared to be related to greater inputs of wastewater to these coastal waters as indicated by high δ15N signatures of the algae as DIN increased. N and P enrichment experiments showed that rate of macroalgal growth was controlled by supply of DIN where ambient DIN concentrations were low, and by P where DIN concentrations were higher, regardless of latitude or geographic setting. These results suggest that understanding the basis for macroalgal blooms, and management of these harmful phenomena, will require information as to nutrient sources, and actions to reduce supply of N and P in coastal waters concerned.

  7. Effects of dietary supplementation of organic acids and phytase on performance and intestinal histomorphology of broilers.

    PubMed

    Mohammadagheri, Nasibeh; Najafi, Ramin; Najafi, Gholamreza

    2016-01-01

    The present experiment was conducted to evaluate the effects of organic acids and phytase enzyme supplementation on performance and intestinal histomorphology of broilers. The experiment was done in a factorial arrangement 2 × 2 × 2 based on completely randomized design with eight treatments, five replicates with 12 chicks in each until 42 days of age. Diets included natural vinegar (0 and 2%), citric acid (CA; 0.00 and 1.00%) and phytase enzyme (PHY; 0.00 and 500 FTU phytase per kg of feed). One bird from each treatment replicate was randomly selected and slaughtered to evaluate the small intestinal morphology on 42 days of age. Analysis of results showed that vinegar increased feed consumption and body weight gain in total experimental period ( p ˂ 0.05), while CA significantly decreased feed consumption on 0-14 days of age ( p ˂ 0.05). No effect was observed on performance in interaction of organic acids together and with PHY group ( p > 0.05). In duodenum CA increased the villus height and width ( p ˂ 0.05) and PHY enzyme increased villus width ( p ˂ 0.05) and decreased crypt depth ( p ˂ 0.05). On the other hand, CA along with PHY significantly decreased crypt depth ( p ˂ 0.05). In jejunum PHY alone and in combination with vinegar increased the goblet cells numbers ( p ˂ 0.05), whereas vinegar significantly increased the goblet cells numbers in ileum ( p ˂ 0.05). The muscular thickness in duodenum, jejunum, and ileum was not affected among different treatment groups. The results showed that supplementation of organic acids and phytase together in this experiment, with no negative effects on each other, improved their effects on some parameters.

  8. Balancing past and present: how experience influences boldness over time in Eurasian perch

    PubMed Central

    Magnhagen, Carin

    2017-01-01

    Abstract Adapting to fluctuating predation conditions is a challenge for prey. By learning through experience, animals may adjust their anti-predator behavior to better reflect current predation risk. Although many studies show experience of predation to alter prey behavior, little is known about how prey rely on such experience over time. By comparing boldness over different temporal scales between individuals of Eurasian perch, either experienced or naïve of predators, we examine how risk is traded based on past and present experience. Differences in predator exposure during the first year of life were found to lead to differences in risk-taking behavior, even after the perch been kept in a predator-free environment for 9 months. However, the response to a potential predator was quickly readjusted after increased experience of current conditions. The results highlight how prey have to balance past experiences of predators against current threat levels. PMID:29491973

  9. Balancing past and present: how experience influences boldness over time in Eurasian perch.

    PubMed

    Hellström, Gustav; Magnhagen, Carin

    2017-04-01

    Adapting to fluctuating predation conditions is a challenge for prey. By learning through experience, animals may adjust their anti-predator behavior to better reflect current predation risk. Although many studies show experience of predation to alter prey behavior, little is known about how prey rely on such experience over time. By comparing boldness over different temporal scales between individuals of Eurasian perch, either experienced or naïve of predators, we examine how risk is traded based on past and present experience. Differences in predator exposure during the first year of life were found to lead to differences in risk-taking behavior, even after the perch been kept in a predator-free environment for 9 months. However, the response to a potential predator was quickly readjusted after increased experience of current conditions. The results highlight how prey have to balance past experiences of predators against current threat levels.

  10. STS-41 crewmembers conduct DSO 0474 Retinal Photography on OV-103's middeck

    NASA Image and Video Library

    1990-10-10

    STS041-02-015 (6-10 Oct. 1990) --- A 35mm scene showing astronauts Robert D. Cabana (right), STS-41 pilot, and Bruce E. Melnick, mission specialist, participating in a detailed supplemental objective for STS-41 involving retinal photography. The hypothesis of this experiment is that retinal photographs taken on orbit will show evidence of increased intracranial pressure (ICP) and the evidence of increased ICP and the development of Space Adaptation Syndrome (SAS) will be correlated. SAS has been a subject of on-orbit analysis since the early days of space shuttle.

  11. The Effect of Global and Local Damping on the Perception of Hardness.

    PubMed

    van Beek, Femke Elise; Heck, Dennis J F; Nijmeijer, Henk; Bergmann Tiest, Wouter M; Kappers, Astrid M L

    2016-01-01

    In tele-operation systems, damping is often injected to guarantee system stability during contact with hard objects. In this study, we used psychophysical experiments to assess the effect of adding damping on the user's perception of object hardness. In Experiments 1 and 2, combinations of stiffness and damping were tested to assess their effect on perceived hardness. In both experiments, two tasks were used: an in-contact task, starting at the object's surface, and a contact-transition task, including a free-air movement. In Experiment 3, the difference between inserting damping globally (equally throughout the workspace) and locally (inside the object only) was tested. In all experiments, the correlation between the participant's perceptual decision and force and position data was also investigated. Experiments 1 and 2 show that when injecting damping globally, perceived hardness slightly increased for an in-contact task, while it decreased considerably for a contact-transition task. Experiment 3 shows that this effect was mainly due to inserting damping globally, since there was a large perceptual difference between inserting damping globally and locally. The force and position parameters suggest that participants used the same force profile during the two movements of one trial and assessed the system's reaction to this force to perceive hardness.

  12. White mulberry (Morus alba) foliage methanolic extract can alleviate Aeromonas hydrophila infection in African catfish (Clarias gariepinus).

    PubMed

    Sheikhlar, Atefeh; Alimon, Abd Razk; Daud, Hassan; Saad, Chee R; Webster, Carl D; Meng, Goh Yong; Ebrahimi, Mahdi

    2014-01-01

    Two experiments were simultaneously conducted with Morus alba (white mulberry) foliage extract (MFE) as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp.) in African catfish (Clarias gariepinus). In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM) of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC), albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM). Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish.

  13. White Mulberry (Morus alba) Foliage Methanolic Extract Can Alleviate Aeromonas hydrophila Infection in African Catfish (Clarias gariepinus)

    PubMed Central

    Sheikhlar, Atefeh; Alimon, Abd Razk; Daud, Hassan; Saad, Chee R.; Webster, Carl D.; Meng, Goh Yong

    2014-01-01

    Two experiments were simultaneously conducted with Morus alba (white mulberry) foliage extract (MFE) as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp.) in African catfish (Clarias gariepinus). In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM) of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC), albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM). Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish. PMID:25574488

  14. Improving the Science Excursion: An Educational Technologist's View

    ERIC Educational Resources Information Center

    Balson, M.

    1973-01-01

    Analyzes the nature of the learning process and attempts to show how the three components of a reinforcement contingency, the stimulus, the response and the reinforcement can be utilized to increase the efficiency of a typical science learning experience, the excursion. (JR)

  15. Principal Mentoring.

    ERIC Educational Resources Information Center

    Malone, Robert

    2001-01-01

    Increasing evidence shows that school leaders, throughout all stages of their careers, can benefit from a mentoring system in which a seasoned leader helps the protege combine theory and practice with experience. This research roundup reviews works that provide support for principal mentoring and share strategies for establishing mentoring…

  16. Survey study of challenging experiences after ingesting psilocybin mushrooms: Acute and enduring positive and negative consequences

    PubMed Central

    Carbonaro, Theresa M; Bradstreet, Matthew P; Barrett, Frederick S; MacLean, Katherine A; Jesse, Robert; Johnson, Matthew W; Griffiths, Roland R

    2017-01-01

    Acute and enduring adverse effects of psilocybin have been reported anecdotally, but have not been well characterized. For this study, 1993 individuals (mean age 30 yrs; 78% male) completed an online survey about their single most psychologically difficult or challenging experience (worst “bad trip”) after consuming psilocybin mushrooms. Thirty-nine percent rated it among the top five most challenging experiences of his/her lifetime. Eleven percent put self or others at risk of physical harm; factors increasing the likelihood of risk included estimated dose, duration and difficulty of the experience, and absence of physical comfort and social support. Of the respondents, 2.6% behaved in a physically aggressive or violent manner and 2.7% received medical help. Of those whose experience occurred >1 year before, 7.6% sought treatment for enduring psychological symptoms. Three cases appeared associated with onset of enduring psychotic symptoms and three cases with attempted suicide. Multiple regression analysis showed degree of difficulty was positively associated, and duration was negatively associated, with enduring increases in well-being. Difficulty of experience was positively associated with dose. Despite difficulties, 84% endorsed benefiting from the experience. The incidence of risky behavior or enduring psychological distress is extremely low when psilocybin is given in laboratory studies to screened, prepared, and supported participants. PMID:27578767

  17. Commercialization of Micro-fabrication of Antenna-Coupled Transition Edge Sensor Bolometer Detectors for Studies of the Cosmic Microwave Background

    NASA Astrophysics Data System (ADS)

    Suzuki, Aritoki; Bebek, Chris; Garcia-Sciveres, Maurice; Holland, Stephen; Kusaka, Akito; Lee, Adrian T.; Palaio, Nicholas; Roe, Natalie; Steinmetz, Leo

    2018-04-01

    We report on the development of commercially fabricated multichroic antenna-coupled transition edge sensor (TES) bolometer arrays for cosmic microwave background (CMB) polarimetry experiments. CMB polarimetry experiments have deployed instruments in stages. Stage II experiments deployed with O(1000) detectors and reported successful detection of B-mode (divergence-free) polarization pattern in the CMB. Stage III experiments have recently started observing with O(10,000) detectors with wider frequency coverage. A concept for a stage IV experiment, CMB-S4, is emerging to make a definitive measurement of CMB polarization from the ground with O(400,000) detectors. The orders of magnitude increase in detector count for CMB-S4 require a new approach in detector fabrication to increase fabrication throughput and reduce the cost. We report on collaborative efforts with two commercial micro-fabrication foundries to fabricate antenna-coupled TES bolometer detectors. The detector design is based on the sinuous antenna-coupled dichroic detector from the POLARBEAR-2 experiment. The TES bolometers showed the expected I-V response, and the RF performance agrees with the simulation. We will discuss the motivation, design consideration, fabrication processes, test results, and how industrial detector fabrication could be a path to fabricate hundreds of detector wafers for future CMB polarimetry experiments.

  18. Theory versus experiment for the rotordynamic coefficients of labyrinth gas seals. II - A comparison to experiment

    NASA Technical Reports Server (NTRS)

    Childs, D. W.; Scharrer, J. K.

    1987-01-01

    An experimental test facility is used to measure the leakage and rotordynamic coefficients of teeth-on-rotor and teeth-on-stator labyrinth gas seals. The test results are presented along with the theoretically predicted values for the two seal configurations at three different radial clearances and shaft speeds to 16,000 cpm. The test results show that the theory accurately predicts the cross-coupled stiffness for both seal configurations and shows improvement in the prediction of the direct damping for the teeth-on-rotor seal. The theory fails to predict a decrease in the direct damping coefficient for an increase in the radial clearance for the teeth-on-stator seal.

  19. Experimental violation of multipartite Bell inequalities with trapped ions.

    PubMed

    Lanyon, B P; Zwerger, M; Jurcevic, P; Hempel, C; Dür, W; Briegel, H J; Blatt, R; Roos, C F

    2014-03-14

    We report on the experimental violation of multipartite Bell inequalities by entangled states of trapped ions. First, we consider resource states for measurement-based quantum computation of between 3 and 7 ions and show that all strongly violate a Bell-type inequality for graph states, where the criterion for violation is a sufficiently high fidelity. Second, we analyze Greenberger-Horne-Zeilinger states of up to 14 ions generated in a previous experiment using stronger Mermin-Klyshko inequalities, and show that in this case the violation of local realism increases exponentially with system size. These experiments represent a violation of multipartite Bell-type inequalities of deterministically prepared entangled states. In addition, the detection loophole is closed.

  20. Prosocial Bonuses Increase Employee Satisfaction and Team Performance

    PubMed Central

    Anik, Lalin; Aknin, Lara B.; Norton, Michael I.; Dunn, Elizabeth W.; Quoidbach, Jordi

    2013-01-01

    In three field studies, we explore the impact of providing employees and teammates with prosocial bonuses, a novel type of bonus spent on others rather than on oneself. In Experiment 1, we show that prosocial bonuses in the form of donations to charity lead to happier and more satisfied employees at an Australian bank. In Experiments 2a and 2b, we show that prosocial bonuses in the form of expenditures on teammates lead to better performance in both sports teams in Canada and pharmaceutical sales teams in Belgium. These results suggest that a minor adjustment to employee bonuses – shifting the focus from the self to others – can produce measurable benefits for employees and organizations. PMID:24058691

  1. Prosocial bonuses increase employee satisfaction and team performance.

    PubMed

    Anik, Lalin; Aknin, Lara B; Norton, Michael I; Dunn, Elizabeth W; Quoidbach, Jordi

    2013-01-01

    In three field studies, we explore the impact of providing employees and teammates with prosocial bonuses, a novel type of bonus spent on others rather than on oneself. In Experiment 1, we show that prosocial bonuses in the form of donations to charity lead to happier and more satisfied employees at an Australian bank. In Experiments 2a and 2b, we show that prosocial bonuses in the form of expenditures on teammates lead to better performance in both sports teams in Canada and pharmaceutical sales teams in Belgium. These results suggest that a minor adjustment to employee bonuses--shifting the focus from the self to others--can produce measurable benefits for employees and organizations.

  2. [The cariogenicity of xylitol in the animal experiment].

    PubMed

    Karle, E J

    1977-01-01

    After programmed feeding of rats in a six and eight-week long conventional experiment with increasing concentrations of xylitol, compared to sorbitol, fructose and saccharose, the non-cariogenic nature of xylitol was confirmed. The increasing amounts of xylitol after sorbitol in chocolate diets (up to 30 g/day/rat) led to serious dilatation of the cecum and to changes in the mucosa of cecum and colon when sorbitol was given. Examination of plaques of the germ-free rats monoassociated with S. mutans showed that xylitol had no bacteriostatic effect on this type of germ. Since xylitol is not broken down by these germs with acid being formed, careis did not continue to extend.

  3. Brain-computer interface for alertness estimation and improving

    NASA Astrophysics Data System (ADS)

    Hramov, Alexander; Maksimenko, Vladimir; Hramova, Marina

    2018-02-01

    Using wavelet analysis of the signals of electrical brain activity (EEG), we study the processes of neural activity, associated with perception of visual stimuli. We demonstrate that the brain can process visual stimuli in two scenarios: (i) perception is characterized by destruction of the alpha-waves and increase in the high-frequency (beta) activity, (ii) the beta-rhythm is not well pronounced, while the alpha-wave energy remains unchanged. The special experiments show that the motivation factor initiates the first scenario, explained by the increasing alertness. Based on the obtained results we build the brain-computer interface and demonstrate how the degree of the alertness can be estimated and controlled in real experiment.

  4. Haloperidol increases false recognition memory of thematically related pictures in healthy volunteers.

    PubMed

    Guarnieri, Regina V; Buratto, Luciano G; Gomes, Carlos F A; Ribeiro, Rafaela L; de Souza, Altay A Lino; Stein, Lilian M; Galduróz, José C; Bueno, Orlando F A

    2017-01-01

    Dopamine can modulate long-term episodic memory. Its potential role on the generation of false memories, however, is less well known. In a randomized, double-blind, placebo-controlled experiment, 24 young healthy volunteers ingested a 4-mg oral dose of haloperidol, a dopamine D 2 -receptor antagonist, or placebo, before taking part in a recognition memory task. Haloperidol was active during both study and test phases of the experiment. Participants in the haloperidol group produced more false recognition responses than those in the placebo group, despite similar levels of correct recognition. These findings show that dopamine blockade in healthy volunteers can specifically increase false recognition memory. Copyright © 2016 John Wiley & Sons, Ltd.

  5. Body heating induced by sub-resonant (350 MHz) microwave irradiation: cardiovascular and respiratory responses in anesthetized rats.

    PubMed

    Jauchem, J R; Frei, M R

    1997-01-01

    These experiments were designed to investigate the effects of sub-resonant microwave (MW) exposure (350 MHz, E orientation, average power density 38 mW/cm2, average whole-body specific absorption rate 13.2 W/kg) on selected physiological parameters. The increase in peripheral body temperature during 350 MHz exposure was greater than that in earlier experiments performed at 700 MHz (resonance). Heart rate and mean arterial blood pressure were significantly elevated during a 1 degree C increase in colonic temperature due to 350 MHz exposure; respiratory rate showed no significant change. The results are consistent with other investigators' reports comparing sub-resonance exposures with those at resonance and above.

  6. Supersonic combustion ramjet propulsion experiments in a shock tunnel

    NASA Technical Reports Server (NTRS)

    Paull, A.; Stalker, R. J.; Mee, D. J.

    1995-01-01

    Measurements have been made of the propulsive effect of supersonic combustion ramjets incorporated into a simple axisymmetric model in a free piston shock tunnel. The nominal Mach number was 6, and the stagnation enthalpy varied from 2.8 MJ kg(exp -1) to 8.5 MJ kg(exp -1). A mixture of 13 percent silane and 87 percent hydrogen was used as fuel, and experiments were conducted at equivalence ratios up to approximately 0.8. The measurements involved the axial force on the model, and were made using a stress wave force balance, which is a recently developed technique for measuring forces in shock tunnels. A net thrust was experienced up to a stagnation enthalpy of 3.7 MJ kg(exp -1), but as the stagnation enthalpy increased, an increasing net drag was recorded. pitot and static pressure measurements showed that the combustion was supersonic. The results were found to compare satisfactorily with predictions based on established theoretical models, used with some simplifying approximations. The rapid reduction of net thrust with increasing stagnation enthalpy was seen to arise from increasing precombustion temperature, showing the need to control this variable if thrust performance was to be maintained over a range of stagnation enthalpies. Both the inviscid and viscous drag were seen to be relatively insensitive to stagnation enthalpy, with the combustion chambers making a particularly significant contribution to drag. The maximum fuel specific impulse achieved in the experiments was only 175 sec., but the theory indicates that there is considerable scope for improvement on this through aerodynamic design.

  7. The ugliness-in-averageness effect: Tempering the warm glow of familiarity.

    PubMed

    Carr, Evan W; Huber, David E; Pecher, Diane; Zeelenberg, Rene; Halberstadt, Jamin; Winkielman, Piotr

    2017-06-01

    Mere exposure (i.e., stimulus repetition) and blending (i.e., stimulus averaging) are classic ways to increase social preferences, including facial attractiveness. In both effects, increases in preference involve enhanced familiarity. Prominent memory theories assume that familiarity depends on a match between the target and similar items in memory. These theories predict that when individual items are weakly learned, their blends (morphs) should be relatively familiar, and thus liked-a beauty-in-averageness effect ( BiA ). However, when individual items are strongly learned, they are also more distinguishable. This "differentiation" hypothesis predicts that with strongly encoded items, familiarity (and thus, preference) for the blend will be relatively lower than individual items-an ugliness-in-averageness effect ( UiA ). We tested this novel theoretical prediction in 5 experiments. Experiment 1 showed that with weak learning, facial morphs were more attractive than contributing individuals (BiA effect). Experiments 2A and 2B demonstrated that when participants first strongly learned a subset of individual faces (either in a face-name memory task or perceptual-tracking task), morphs of trained individuals were less attractive than the trained individuals (UiA effect). Experiment 3 showed that changes in familiarity for the trained morph (rather than interstimulus conflict) drove the UiA effect. Using a within-subjects design, Experiment 4 mapped out the transition from BiA to UiA solely as a function of memory training. Finally, computational modeling using a well-known memory framework (REM) illustrated the familiarity transition observed in Experiment 4. Overall, these results highlight how memory processes illuminate classic and modern social preference phenomena. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. Clinopyroxene dissolution in basaltic melt

    NASA Astrophysics Data System (ADS)

    Chen, Yang; Zhang, Youxue

    2009-10-01

    The history of magmatic systems may be inferred from reactions between mantle xenoliths and host basalt if the thermodynamics and kinetics of the reactions are quantified. To study diffusive and convective clinopyroxene dissolution in silicate melts, diffusive clinopyroxene dissolution experiments were conducted at 0.47-1.90 GPa and 1509-1790 K in a piston-cylinder apparatus. Clinopyroxene saturation is found to be roughly determined by MgO and CaO content. The effective binary diffusivities, DMgO and DCaO, and the interface melt saturation condition, C0MgO×C0CaO, are extracted from the experiments. DMgO and DCaO show Arrhenian dependence on temperature. The pressure dependence is small and not resolved within 0.47-1.90 GPa. C0MgO×C0CaO in the interface melt increases with increasing temperature, but decreases with increasing pressure. Convective clinopyroxene dissolution, where the convection is driven by the density difference between the crystal and melt, is modeled using the diffusivities and interface melt saturation condition. Previous studies showed that the convective dissolution rate depends on the thermodynamics, kinetics and fluid dynamics of the system. Comparing our results for clinopyroxene dissolution to results from a previous study on convective olivine dissolution shows that the kinetic and fluid dynamic aspects of the two minerals are quite similar. However, the thermodynamics of clinopyroxene dissolution depends more strongly on the degree of superheating and composition of the host melt than that of olivine dissolution. The models for clinopyroxene and olivine dissolution are tested against literature experiments on mineral-melt interaction. They are then applied to previously proposed reactions between Hawaii basalts and mantle minerals, mid-ocean ridge basalts and mantle minerals, and xenoliths digestion in a basalt at Kuandian, Northeast China.

  9. Existence of consistent hypo- and hyperresponders to dietary cholesterol in man.

    PubMed

    Katan, M B; Beynen, A C; de Vries, J H; Nobels, A

    1986-02-01

    Hyper- and hyporesponsiveness of serum cholesterol to dietary cholesterol is an established concept in animals but not in man. The authors studied the stability of the individual response of serum cholesterol to dietary cholesterol in three controlled experiments in 1982. The subjects were volunteers from the general population living in or near Wageningen, the Netherlands. Each experiment had a low-cholesterol baseline period (121, 106, and 129 mg/day in experiments 1, 2, and 3, respectively) and a high-cholesterol test period (625, 673, and 989 mg/day). Duplicate portion analysis showed that dietary cholesterol was the only variable. The 94 healthy men and women who completed experiment 1 showed an increase (mean +/- standard deviation (SD] in serum cholesterol of 0.50 +/- 0.39 mmol/liter (19 +/- 15 mg/dl). Seventeen putative hyperresponders, defined by their response in experiment 1, were retested in experiments 2 and 3; they showed responses of 0.28 +/- 0.38 mmol/liter (11 +/- 15 mg/dl) and 0.82 +/- 0.35 mmol/liter (32 +/- 14 mg/dl), respectively. Fifteen hyporesponders, selected in experiment 1, showed responses in experiments 2 and 3 of 0.06 +/- 0.35 mmol/liter (2 +/- 14 mg/dl) and 0.47 +/- 0.26 mmol/liter (18 +/- 10 mg/dl), significantly lower than the corresponding values for hyperresponders. The standardized regression coefficient for individual responses in experiment 2 on those in experiment 1 was beta = 0.34 (p = 0.03, n = 32); the corresponding regression coefficient for experiment 3 and experiment 1 was 0.53 (p less than 0.01). After correction for intraindividual fluctuations the true responsiveness distribution was found to have a between-subject standard deviation of about 0.29 mmol/liter (11 mg/dl). This implies that if the mean response to a certain dietary cholesterol load amounts to e.g., 0.58 mmol/liter (22 mg/dl), then the 16% of subjects least susceptible to diet will experience a rise of only 0.29 mmol/liter (11 mg/dl) or less, while in the 16% of subjects most susceptible to diet, serum cholesterol will rise by 0.87 mmol/liter (34 mg/dl) or more. The authors conclude that modest differences in responsiveness of serum cholesterol to dietary cholesterol do exist in man, and that the wide scatter of responses observed in single experiments is largely due to chance fluctuations.

  10. Resource Availability Alters Biodiversity Effects in Experimental Grass-Forb Mixtures.

    PubMed

    Siebenkäs, Alrun; Schumacher, Jens; Roscher, Christiane

    2016-01-01

    Numerous experiments, mostly performed in particular environments, have shown positive diversity-productivity relationships. Although the complementary use of resources is discussed as an important mechanism explaining diversity effects, less is known about how resource availability controls the strength of diversity effects and how this response depends on the functional composition of plant communities. We studied aboveground biomass production in experimental monocultures, two- and four-species mixtures assembled from two independent pools of four perennial grassland species, each representing two functional groups (grasses, forbs) and two growth statures (small, tall), and exposed to different combinations of light and nutrient availability. On average, shade led to a decrease in aboveground biomass production of 24% while fertilization increased biomass production by 36%. Mixtures were on average more productive than expected from their monocultures (relative yield total, RYT>1) and showed positive net diversity effects (NE: +34% biomass increase; mixture minus mean monoculture biomass). Both trait-independent complementarity effects (TICE: +21%) and dominance effects (DE: +12%) positively contributed to net diversity effects, while trait-dependent complementarity effects were minor (TDCE: +1%). Shading did not alter diversity effects and overyielding. Fertilization decreased RYT and the proportion of biomass gain through TICE and TDCE, while DE increased. Diversity effects did not increase with species richness and were independent of functional group or growth stature composition. Trait-based analyses showed that the dominance of species with root and leaf traits related to resource conservation increased TICE. Traits indicating the tolerance of shade showed positive relationships with TDCE. Large DE were associated with the dominance of species with tall growth and low diversity in leaf nitrogen concentrations. Our field experiment shows that positive diversity effects are possible in grass-forb mixtures irrespective of differences in light availability, but that the chance for the complementary use of resources increases when nutrients are not available at excess.

  11. Resource Availability Alters Biodiversity Effects in Experimental Grass-Forb Mixtures

    PubMed Central

    Siebenkäs, Alrun; Schumacher, Jens; Roscher, Christiane

    2016-01-01

    Numerous experiments, mostly performed in particular environments, have shown positive diversity-productivity relationships. Although the complementary use of resources is discussed as an important mechanism explaining diversity effects, less is known about how resource availability controls the strength of diversity effects and how this response depends on the functional composition of plant communities. We studied aboveground biomass production in experimental monocultures, two- and four-species mixtures assembled from two independent pools of four perennial grassland species, each representing two functional groups (grasses, forbs) and two growth statures (small, tall), and exposed to different combinations of light and nutrient availability. On average, shade led to a decrease in aboveground biomass production of 24% while fertilization increased biomass production by 36%. Mixtures were on average more productive than expected from their monocultures (relative yield total, RYT>1) and showed positive net diversity effects (NE: +34% biomass increase; mixture minus mean monoculture biomass). Both trait-independent complementarity effects (TICE: +21%) and dominance effects (DE: +12%) positively contributed to net diversity effects, while trait-dependent complementarity effects were minor (TDCE: +1%). Shading did not alter diversity effects and overyielding. Fertilization decreased RYT and the proportion of biomass gain through TICE and TDCE, while DE increased. Diversity effects did not increase with species richness and were independent of functional group or growth stature composition. Trait-based analyses showed that the dominance of species with root and leaf traits related to resource conservation increased TICE. Traits indicating the tolerance of shade showed positive relationships with TDCE. Large DE were associated with the dominance of species with tall growth and low diversity in leaf nitrogen concentrations. Our field experiment shows that positive diversity effects are possible in grass-forb mixtures irrespective of differences in light availability, but that the chance for the complementary use of resources increases when nutrients are not available at excess. PMID:27341495

  12. Déjà vu experiences in schizophrenia: relations with psychopathology and antipsychotic medication.

    PubMed

    Adachi, Naoto; Adachi, Takuya; Akanuma, Nozomi; Matsubara, Ryouji; Ito, Masumi; Takekawa, Yoshikazu; Ikeda, Hiroshi; Arai, Heii

    2007-01-01

    To clarify why patients with schizophrenia show déjà vu experiences less frequently, we studied déjà vu experiences in 113 schizophrenic patients in relation to psychopathologies and antipsychotic medication. Déjà vu experiences were observed in 53.1% of the schizophrenic patients. Patients with increased negative symptoms (blunted affect, motor retardation, emotional withdrawal, conceptual disorganization, and mannerisms) had déjà vu experiences less frequently. The other psychopathologies were not significantly associated with presence of déjà vu experiences. The dosage of antipsychotic drugs was significantly correlated with the frequency of déjà vu experiences. This correlation was not affected by their psychopathologies at the time of examination. The decreased frequency of déjà vu experiences in patients with schizophrenia may be mainly due to the negative symptoms. The positive relation between frequency of déjà vu experiences and the dosage of neuroleptics remains uncertain.

  13. Do prevailing societal models influence reports of near-death experiences?: a comparison of accounts reported before and after 1975.

    PubMed

    Athappilly, Geena K; Greyson, Bruce; Stevenson, Ian

    2006-03-01

    Transcendental near-death experiences show some cross-cultural variation that suggests they may be influenced by societal beliefs. The prevailing Western model of near-death experiences was defined by Moody's description of the phenomenon in 1975. To explore the influence of this cultural model, we compared near-death experience accounts collected before and after 1975. We compared the frequency of 15 phenomenological features Moody defined as characteristic of near-death experiences in 24 accounts collected before 1975 and in 24 more recent accounts matched on relevant demographic and situational variables. Near-death experience accounts collected after 1975 differed from those collected earlier only in increased frequency of tunnel phenomena, which other research has suggested may not be integral to the experience, and not in any of the remaining 14 features defined by Moody as characteristic of near-death experiences. These data challenge the hypothesis that near-death experience accounts are substantially influenced by prevailing cultural models.

  14. Emotion computing using Word Mover's Distance features based on Ren_CECps.

    PubMed

    Ren, Fuji; Liu, Ning

    2018-01-01

    In this paper, we propose an emotion separated method(SeTF·IDF) to assign the emotion labels of sentences with different values, which has a better visual effect compared with the values represented by TF·IDF in the visualization of a multi-label Chinese emotional corpus Ren_CECps. Inspired by the enormous improvement of the visualization map propelled by the changed distances among the sentences, we being the first group utilizes the Word Mover's Distance(WMD) algorithm as a way of feature representation in Chinese text emotion classification. Our experiments show that both in 80% for training, 20% for testing and 50% for training, 50% for testing experiments of Ren_CECps, WMD features get the best f1 scores and have a greater increase compared with the same dimension feature vectors obtained by dimension reduction TF·IDF method. Compared experiments in English corpus also show the efficiency of WMD features in the cross-language field.

  15. Task conflict effect in task switching.

    PubMed

    Braverman, Ami; Meiran, Nachshon

    2010-11-01

    A part of action preparation is deciding what the relevant task is. This task-decision process is conceptually separate from response selection. To show this, the authors manipulated task conflict in a spatial task-switching paradigm, using conflict stimuli that appeared during trials with univalent targets (affording 1 task). The conflict stimuli afforded task identity because they were used as task cues with bivalent targets (affording 2 tasks) that were intermixed with the univalent targets. Thus, for univalent targets, irrelevant stimuli either caused low task conflict or high task conflict. In three experiments, the authors found poorer performance in high task conflict trials than in low task conflict trials. Task conflict was introduced during target appearance (Experiment 1) or task preparation (Experiments 2 and 3). In the latter case, the task conflict effect decreased with increasing task preparation time showing that task preparation involves task decision.

  16. Retinal changes in rats flown on Cosmos 936 - A cosmic ray experiment

    NASA Technical Reports Server (NTRS)

    Philpott, D. E.; Corbett, R.; Turnbill, C.; Black, S.; Dayhoff, D.; Mcgourty, J.; Lee, R.; Harrison, G.; Savik, L.

    1980-01-01

    Ten rats, five centrifuged during flight to simulate gravity and five stationary in flight and experiencing hypogravity, orbited the Earth. No differences were noted between flight-stationary and flight-centrifuged animals, but changes were seen between these two groups and ground controls. Morphological alterations were observed comparable to those in the experiment flown on Cosmos 782 and to the retinal cells exposed to high-energy particles at Berkeley. Affected cells in the outer nuclear layer showed swelling, clearing of cytoplasm, and disruption of the membranes. Tissue channels were again found, similar to those seen on 782. After space flight, preliminary data indicated an increase in cell size in montages of the nuclear layer of both groups of flight animals. This experiment shows that weightlessness and environmental conditions other than cosmic radiation do not contribute to the observed damage of retinal cells.

  17. Analogical transfer as guided by an abstraction process: the case of learning by doing in text editing.

    PubMed

    Sander, E; Richard, J F

    1997-11-01

    The authors proposed that not only are the first attempts to solve a problem made by analogy but also that progress in learning can be guided by referring to more abstract knowledge, which affords new possibilities. Two experiments investigated this view in a situation of learning how to use a text editor. Experiments 1A to 1C identified the knowledge associated with 3 domains hypothesized as sources of transfer at increasing levels of abstraction (typewriting, writing in general, manipulating objects). Experiment 2 tested whether participants first use their knowledge about typewriting, then about writing in general, and then about manipulating objects. The data showed that the order of acquisition of text editor functions appeared to be strongly related to this hierarchy, supporting the idea that part of learning consists of discovering properties of objects by accessing increasingly general domains.

  18. Implementation of 7e learning cycle model using technology based constructivist teaching (TBCT) approach to improve students' understanding achievment in mechanical wave material

    NASA Astrophysics Data System (ADS)

    Warliani, Resti; Muslim, Setiawan, Wawan

    2017-05-01

    This study aims to determine the increase in the understanding achievement in senior high school students through the Learning Cycle 7E with technology based constructivist teaching approach (TBCT). This study uses a pretest-posttest control group design. The participants were 67 high school students of eleventh grade in Garut city with two class in control and experiment class. Experiment class applying the Learning Cycle 7E through TBCT approach and control class applying the 7E Learning Cycle through Constructivist Teaching approach (CT). Data collection tools from mechanical wave concept test with totally 22 questions with reability coefficient was found 0,86. The findings show the increase of the understanding achievement of the experiment class is in the amount of 0.51 was higher than the control class that is in the amount of 0.33.

  19. The Developmental Dynamics of Terrorist Organizations

    PubMed Central

    Clauset, Aaron; Gleditsch, Kristian Skrede

    2012-01-01

    We identify robust statistical patterns in the frequency and severity of violent attacks by terrorist organizations as they grow and age. Using group-level static and dynamic analyses of terrorist events worldwide from 1968–2008 and a simulation model of organizational dynamics, we show that the production of violent events tends to accelerate with increasing size and experience. This coupling of frequency, experience and size arises from a fundamental positive feedback loop in which attacks lead to growth which leads to increased production of new attacks. In contrast, event severity is independent of both size and experience. Thus larger, more experienced organizations are more deadly because they attack more frequently, not because their attacks are more deadly, and large events are equally likely to come from large and small organizations. These results hold across political ideologies and time, suggesting that the frequency and severity of terrorism may be constrained by fundamental processes. PMID:23185267

  20. Chronic exposure to neonicotinoids reduces honey bee health near corn crops.

    PubMed

    Tsvetkov, N; Samson-Robert, O; Sood, K; Patel, H S; Malena, D A; Gajiwala, P H; Maciukiewicz, P; Fournier, V; Zayed, A

    2017-06-30

    Experiments linking neonicotinoids and declining bee health have been criticized for not simulating realistic exposure. Here we quantified the duration and magnitude of neonicotinoid exposure in Canada's corn-growing regions and used these data to design realistic experiments to investigate the effect of such insecticides on honey bees. Colonies near corn were naturally exposed to neonicotinoids for up to 4 months-the majority of the honey bee's active season. Realistic experiments showed that neonicotinoids increased worker mortality and were associated with declines in social immunity and increased queenlessness over time. We also discovered that the acute toxicity of neonicotinoids to honey bees doubles in the presence of a commonly encountered fungicide. Our work demonstrates that field-realistic exposure to neonicotinoids can reduce honey bee health in corn-growing regions. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  1. Updating representations of learned scenes.

    PubMed

    Finlay, Cory A; Motes, Michael A; Kozhevnikov, Maria

    2007-05-01

    Two experiments were designed to compare scene recognition reaction time (RT) and accuracy patterns following observer versus scene movement. In Experiment 1, participants memorized a scene from a single perspective. Then, either the scene was rotated or the participants moved (0 degrees -360 degrees in 36 degrees increments) around the scene, and participants judged whether the objects' positions had changed. Regardless of whether the scene was rotated or the observer moved, RT increased with greater angular distance between judged and encoded views. In Experiment 2, we varied the delay (0, 6, or 12 s) between scene encoding and locomotion. Regardless of the delay, however, accuracy decreased and RT increased with angular distance. Thus, our data show that observer movement does not necessarily update representations of spatial layouts and raise questions about the effects of duration limitations and encoding points of view on the automatic spatial updating of representations of scenes.

  2. Evaluating transition-metal catalysis in gas generation from the Permian Kupferschiefer by hydrous pyrolysis

    USGS Publications Warehouse

    Lewan, M.D.; Kotarba, M.J.; Wieclaw, D.; Piestrzynski, A.

    2008-01-01

    Transition metals in source rocks have been advocated as catalysts in determining extent, composition, and timing of natural gas generation (Mango, F. D. (1996) Transition metal catalysis in the generation of natural gas. Org. Geochem.24, 977–984). This controversial hypothesis may have important implications concerning gas generation in unconventional shale-gas accumulations. Although experiments have been conducted to test the metal-catalysis hypothesis, their approach and results remain equivocal in evaluating natural assemblages of transition metals and organic matter in shale. The Permian Kupferschiefer of Poland offers an excellent opportunity to test the hypothesis with immature to marginally mature shale rich in both transition metals and organic matter. Twelve subsurface samples containing similar Type-II kerogen with different amounts and types of transition metals were subjected to hydrous pyrolysis at 330° and 355 °C for 72 h. The gases generated in these experiments were quantitatively collected and analyzed for molecular composition and stable isotopes. Expelled immiscible oils, reacted waters, and spent rock were also quantitatively collected. The results show that transition metals have no effect on methane yields or enrichment. δ13C values of generated methane, ethane, propane and butanes show no systematic changes with increasing transition metals. The potential for transition metals to enhance gas generation and oil cracking was examined by looking at the ratio of the generated hydrocarbon gases to generated expelled immiscible oil (i.e., GOR), which showed no systematic change with increasing transition metals. Assuming maximum yields at 355 °C for 72 h and first-order reaction rates, pseudo-rate constants for methane generation at 330 °C were calculated. These rate constants showed no increase with increasing transition metals. The lack of a significant catalytic effect of transition metals on the extent, composition, and timing of natural gas generation in these experiments is attributed to the metals not occurring in the proper form or the poisoning of potential catalytic microcosms by polar-rich bitumen, which impregnates the rock matrix during the early stages of petroleum formation.

  3. Dissolution kinetics of volatile organic compound vapors in water: An integrated experimental and computational study

    NASA Astrophysics Data System (ADS)

    Mahmoodlu, Mojtaba G.; Pontedeiro, Elizabeth M.; Pérez Guerrero, Jesús S.; Raoof, Amir; Majid Hassanizadeh, S.; van Genuchten, Martinus Th.

    2017-01-01

    In this study we performed batch experiments to investigate the dissolution kinetics of trichloroethylene (TCE) and toluene vapors in water at room temperature and atmospheric pressure. The batch systems consisted of a water reservoir and a connected headspace, the latter containing a small glass cylinder filled with pure volatile organic compound (VOC). Results showed that air phase concentrations of both TCE and toluene increased relatively quickly to their maximum values and then became constant. We considered subsequent dissolution into both stirred and unstirred water reservoirs. Results of the stirred experiments showed a quick increase in the VOC concentrations with time up to their solubility limit in water. VOC vapor dissolution was found to be independent of pH. In contrast, salinity had a significant effect on the solubility of TCE and toluene vapors. VOC evaporation and vapor dissolution in the stirred water reservoirs followed first-order rate processes. Observed data could be described well using both simplified analytical solutions, which decoupled the VOC dynamics in the air and water phases, as well as using more complete coupled solutions. However, the estimated evaporation (ke) and dissolution (kd) rate constants differed by up to 70% between the coupled and uncoupled formulations. We also numerically investigated the effects of fluid withdrawal from the small water reservoir due to sampling. While decoupling the VOC air and water phase mass transfer processes produced unreliable estimates of kd, the effects of fluid withdrawal on the estimated rate constants were found to be less important. The unstirred experiments showed a much slower increase in the dissolved VOC concentrations versus time. Molecular diffusion of the VOCs within the aqueous phase became then the limiting factor for mass transfer from air to water. Fluid withdrawal during sampling likely caused some minor convection within the reservoir, which was simulated by increasing the apparent liquid diffusion coefficient.

  4. Concentration-Dependent Inhibitory Effect of Baicalin on the Plasma Protein Binding and Metabolism of Chlorzoxazone, a CYP2E1 Probe Substrate, in Rats In Vitro and In Vivo

    PubMed Central

    Gao, Na; Zou, Dan; Qiao, Hai-Ling

    2013-01-01

    Some of the components found in herbs may be inhibitors or inducers of cytochrome P450 enzymes, which may therefore result in undesired herb-drug interactions. As a component extracted from Radix Scutellariae, the direct effect of baicalin on cytochrome P450 has not been investigated sufficiently. In this study, we investigated concentration-dependent inhibitory effect of baicalin on the plasma protein binding and metabolism of chlorzoxazone (CZN), a model CYP2E1 probe substrate, in rats in vitro and in vivo. Animal experiment was a randomized, three-period crossover design. Significant changes in pharmacokinetic parameters of CZN such as Cmax, t1/2 and Vd were observed after treatment with baicalin in vivo (P<0.05). Cmax decreased by 25% and 33%, whereas t1/2 increased by 34% and 53%, Vd increased by 37% and 50% in 225 mg/kg and 450 mg/kg baicalin-treated rats, respectively. The AUC and CL of CZN were not affected (P>0.05). Correlation analysis showed that the changes in CZN concentrations and baicalin concentrations were in good correlation (r>0.99). In vitro experiments, baicalin decreased the formation of 6-OH-chlorzoxazone in a concentration-dependent manner and exhibited a competitive inhibition in rat liver microsomes, with a Ki value of 145.8 µM. The values of Cmax/Ki were 20 and 39 after treatment with baicalin (225 and 450 mg/kg), respectively. Protein binding experiments in vivo showed that the plasma free-fraction (fu) of CZN increased 2.6-fold immediately after baicalin treatment (450 mg/kg) and in vitro showed that baicalin (125–2500 mg/L) increased the unbound CZN from 1.63% to 3.58%. The results indicate that pharmacokinetic changes in CZN are induced by inhibitory effect of baicalin on the plasma protein binding of CZN and CYP2E1 activity. PMID:23301016

  5. Word length, set size, and lexical factors: Re-examining what causes the word length effect.

    PubMed

    Guitard, Dominic; Gabel, Andrew J; Saint-Aubin, Jean; Surprenant, Aimée M; Neath, Ian

    2018-04-19

    The word length effect, better recall of lists of short (fewer syllables) than long (more syllables) words has been termed a benchmark effect of working memory. Despite this, experiments on the word length effect can yield quite different results depending on set size and stimulus properties. Seven experiments are reported that address these 2 issues. Experiment 1 replicated the finding of a preserved word length effect under concurrent articulation for large stimulus sets, which contrasts with the abolition of the word length effect by concurrent articulation for small stimulus sets. Experiment 2, however, demonstrated that when the short and long words are equated on more dimensions, concurrent articulation abolishes the word length effect for large stimulus sets. Experiment 3 shows a standard word length effect when output time is equated, but Experiments 4-6 show no word length effect when short and long words are equated on increasingly more dimensions that previous demonstrations have overlooked. Finally, Experiment 7 compared recall of a small and large neighborhood words that were equated on all the dimensions used in Experiment 6 (except for those directly related to neighborhood size) and a neighborhood size effect was still observed. We conclude that lexical factors, rather than word length per se, are better predictors of when the word length effect will occur. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  6. The effect of seawater on thermoregulator centers

    NASA Technical Reports Server (NTRS)

    Dontas, S.; Phocas, E.

    1978-01-01

    Experiments were done on dogs to determine the mechanism of thermoregulation. Results show that natural seawater, injected intravenously (150, 200, and 300 cc ), causes narcosis of the thermic centers and increases temperature. Diluted seawater injection causes an excitation of the thermic centers and an antipyretic effect.

  7. ELECTROSTATIC ENHANCEMENT OF FABRIC FILTRATION OF FLY ASH AND SPRAY DRYER BY-PRODUCT

    EPA Science Inventory

    The paper describes small pilot-scale experiments, showing that the pressure drop increase during the fabric filtration of redispersed spray dryer by-product (chiefly calcium salts and fly ash) is significantly reduced by electrostatic enhancement of the filtration. The pressure ...

  8. Effect of syrepar and oxaphenamide on liver function in experimental hypokinesia

    NASA Technical Reports Server (NTRS)

    Skakun, L. N.

    1980-01-01

    Experiments on albino rats showed that 30 day hypokinesia changes the reaction of the liver to cholagogues. The choleretic action of oxaphenamide as well as its inhibitory effect on synthesis of bile acids diminishes, while the influence of bilirubin secretion increases.

  9. Addressing Achievement Gaps with Psychological Interventions

    ERIC Educational Resources Information Center

    Yeager, David; Walton, Gregory; Cohen, Geoffrey L.

    2013-01-01

    Student psychology--how the classroom looks and feels from the perspective of the student--can powerfully affect motivation and learning, and experiments are increasingly showing that even brief interventions to change psychology can boost achievement over months or years. When paired with other structural reforms, social-psychological…

  10. Laboratory photochemical processing of aqueous aerosols: formation and degradation of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls

    NASA Astrophysics Data System (ADS)

    Pavuluri, C. M.; Kawamura, K.; Mihalopoulos, N.; Swaminathan, T.

    2015-01-01

    To better understand the photochemical processing of dicarboxylic acids and related polar compounds, we conducted batch UV irradiation experiments on two types of aerosol samples collected from India, which represent anthropogenic (AA) and biogenic aerosols (BA), for time periods of 0.5 to 120 h. The irradiated samples were analyzed for molecular compositions of diacids, oxoacids and α-dicarbonyls. The results show that photochemical degradation of oxalic (C2) and malonic (C3) and other C8-C12 diacids overwhelmed their production in aqueous aerosols whereas succinic acid (C4) and C5-C7 diacids showed a significant increase (ca. 10 times) during the course of irradiation experiments. The photochemical formation of oxoacids and α-dicarbonyls overwhelmed their degradation during the early stages of experiment, except for ω-oxooctanoic acid (ωC8) that showed a similar pattern to that of C4. We also found a gradual decrease in the relative abundance of C2 to total diacids and an increase in the relative abundance of C4 during prolonged experiment. Based on the changes in concentrations and mass ratios of selected species with the irradiation time, we hypothesize that iron-catalyzed photolysis of C2 and C3 diacids dominates their concentrations in Fe-rich atmospheric waters, whereas photochemical formation of C4 diacid (via ωC8) is enhanced with photochemical processing of aqueous aerosols in the atmosphere. This study demonstrates that the ambient aerosols contain abundant precursors that produce diacids, oxoacids and α-dicarbonyls, although some species such as oxalic acid decompose extensively during an early stage of photochemical processing.

  11. Laboratory photochemical processing of aqueous aerosols: formation and degradation of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls

    NASA Astrophysics Data System (ADS)

    Pavuluri, C. M.; Kawamura, K.; Mihalopoulos, N.; Swaminathan, T.

    2015-07-01

    To better understand the photochemical processing of dicarboxylic acids and related polar compounds, we conducted batch UV irradiation experiments on two types of aerosol samples collected from India, which represent anthropogenic (AA) and biogenic (BA) aerosols, for time periods of 0.5 to 120 h. The irradiated samples were analyzed for molecular compositions of diacids, oxoacids and α-dicarbonyls. The results show that photochemical degradation of oxalic (C2), malonic (C3) and other C8-C12 diacids overwhelmed their production in aqueous aerosols, whereas succinic acid (C4) and C5-C7 diacids showed a significant increase (ca. 10 times) during the course of irradiation experiments. The photochemical formation of oxoacids and α-dicarbonyls overwhelmed their degradation during the early stages of experiment except for ω-oxooctanoic acid (ωC8), which showed a similar pattern to that of C4. We also found a gradual decrease in the relative abundance of C2 to total diacids and an increase in the relative abundance of C4 during prolonged experiment. Based on the changes in concentrations and mass ratios of selected species with the irradiation time, we hypothesize that iron-catalyzed photolysis of C2 and C3 diacids controls their concentrations in Fe-rich atmospheric waters, whereas photochemical formation of C4 diacid (via ωC8) is enhanced with photochemical processing of aqueous aerosols in the atmosphere. This study demonstrates that the ambient aerosols contain abundant precursors that produce diacids, oxoacids and α-dicarbonyls, although some species such as oxalic acid decompose extensively during an early stage of photochemical processing.

  12. The interactive effect of social pain and executive functioning on aggression: an fMRI experiment

    PubMed Central

    Eisenberger, Naomi I.; Pond, Richard S.; Richman, Stephanie B.; Bushman, Brad J.; DeWall, C. Nathan

    2014-01-01

    Social rejection often increases aggression, but the neural mechanisms underlying this effect remain unclear. This experiment tested whether neural activity in the dorsal anterior cingulate cortex (dACC) and anterior insula in response to social rejection predicted greater subsequent aggression. Additionally, it tested whether executive functioning moderated this relationship. Participants completed a behavioral measure of executive functioning, experienced social rejection while undergoing functional magnetic resonance imaging and then completed a task in which they could aggress against a person who rejected them using noise blasts . We found that dACC activation and executive functioning interacted to predict aggression. Specifically, participants with low executive functioning showed a positive association between dACC activation and aggression, whereas individuals with high executive functioning showed a negative association. Similar results were found for the left anterior insula. These findings suggest that social pain can increase or decrease aggression, depending on an individual’s regulatory capability. PMID:23482622

  13. [Correlation of substrate structure and hydraulic characteristics in subsurface flow constructed wetlands].

    PubMed

    Bai, Shao-Yuan; Song, Zhi-Xin; Ding, Yan-Li; You, Shao-Hong; He, Shan

    2014-02-01

    The correlation of substrate structure and hydraulic characteristics was studied by numerical simulation combined with experimental method. The numerical simulation results showed that the permeability coefficient of matrix had a great influence on hydraulic efficiency in subsurface flow constructed wetlands. The filler with a high permeability coefficient had a worse flow field distribution in the constructed wetland with single layer structure. The layered substrate structure with the filler permeability coefficient increased from surface to bottom could avoid the short-circuited flow and dead-zones, and thus, increased the hydraulic efficiency. Two parallel pilot-scale constructed wetlands were built according to the numerical simulation results, and tracer experiments were conducted to validate the simulation results. The tracer experiment result showed that hydraulic characteristics in the layered constructed wetland were obviously better than that in the single layer system, and the substrate effective utilization rates were 0.87 and 0.49, respectively. It was appeared that numerical simulation would be favorable for substrate structure optimization in subsurface flow constructed wetlands.

  14. S-Duct Engine Inlet Flow Control Using SDBD Plasma Streamwise Vortex Generators

    NASA Astrophysics Data System (ADS)

    Kelley, Christopher; He, Chuan; Corke, Thomas

    2009-11-01

    The results of a numerical simulation and experiment characterizing the performance of plasma streamwise vortex generators in controlling separation and secondary flow within a serpentine, diffusing duct are presented. A no flow control case is first run to check agreement of location of separation, development of secondary flow, and total pressure recovery between the experiment and numerical results. Upon validation, passive vane-type vortex generators and plasma streamwise vortex generators are implemented to increase total pressure recovery and reduce flow distortion at the aerodynamic interface plane: the exit of the S-duct. Total pressure recovery is found experimentally with a pitot probe rake assembly at the aerodynamic interface plane. Stagnation pressure distortion descriptors are also presented to show the performance increase with plasma streamwise vortex generators in comparison to the baseline no flow control case. These performance parameters show that streamwise plasma vortex generators are an effective alternative to vane-type vortex generators in total pressure recovery and total pressure distortion reduction in S-duct inlets.

  15. Chronic pain induces generalized enhancement of aversion

    PubMed Central

    Zhang, Qiaosheng; Manders, Toby; Tong, Ai Phuong; Yang, Runtao; Garg, Arpan; Martinez, Erik; Zhou, Haocheng; Dale, Jahrane; Goyal, Abhinav; Urien, Louise; Yang, Guang; Chen, Zhe; Wang, Jing

    2017-01-01

    A hallmark feature of chronic pain is its ability to impact other sensory and affective experiences. It is notably associated with hypersensitivity at the site of tissue injury. It is less clear, however, if chronic pain can also induce a generalized site-nonspecific enhancement in the aversive response to nociceptive inputs. Here, we showed that chronic pain in one limb in rats increased the aversive response to acute pain stimuli in the opposite limb, as assessed by conditioned place aversion. Interestingly, neural activities in the anterior cingulate cortex (ACC) correlated with noxious intensities, and optogenetic modulation of ACC neurons showed bidirectional control of the aversive response to acute pain. Chronic pain, however, altered acute pain intensity representation in the ACC to increase the aversive response to noxious stimuli at anatomically unrelated sites. Thus, chronic pain can disrupt cortical circuitry to enhance the aversive experience in a generalized anatomically nonspecific manner. DOI: http://dx.doi.org/10.7554/eLife.25302.001 PMID:28524819

  16. The adsorption of amino acids and cations onto goethite: a prebiotic chemistry experiment.

    PubMed

    Farias, Ana Paula S F; Carneiro, Cristine E A; de Batista Fonseca, Inês C; Zaia, Cássia T B V; Zaia, Dimas A M

    2016-06-01

    Few prebiotic chemistry experiments have assessed the adsorption of biomolecules by iron oxide-hydroxides. The present work investigated the effects of cations in artificial seawaters on the adsorption of Gly, α-Ala and β-Ala onto goethite, and vice versa. Goethite served to concentrate K and Mg cations from solution; these effects could have played important roles in peptide nucleoside formation. Goethite showed low adsorption of Gly and α-Ala. On the other hand, β-Ala (a non-protein amino acid) was highly adsorbed by goethite. Because Gly and α-Ala are the most common amino acids in living beings, and iron oxide-hydroxides are widespread on Earth, additional iron oxides should be studied. Increased ionic strength in artificial seawaters decreased the adsorption of amino acids by goethite. Because Na was highly abundant in the artificial seawater, it showed the highest effect on amino acid adsorption. β-Ala increased the adsorption of K and Ca by goethite, this effect could have been important for peptide synthesis.

  17. Experimental study of the condensation heat transfer characteristics of CO2 in a horizontal microfin tube with a diameter of 4.95 mm

    NASA Astrophysics Data System (ADS)

    Son, Chang-Hyo; Oh, Hoo-Kyu

    2012-11-01

    The condensation heat transfer characteristics for CO2 flowing in a horizontal microfin tube were investigated by experiment with respect to condensation temperature and mass flux. The test section consists of a 2,400 mm long horizontal copper tube of 4.6 mm inner diameter. The experiments were conducted at refrigerant mass flux of 400-800 kg/m2s, and saturation temperature of 20-30 °C. The main experimental results showed that annular flow was highly dominated the majority of condensation flow in the horizontal microfin tube. The condensation heat transfer coefficient increases with decreasing saturation temperature and increasing mass flux. The experimental data were compared against previous heat transfer correlations. Most correlations failed to predict the experimental data. However, the correlation by Cavallini et al. showed relatively good agreement with experimental data in the microfin tube. Therefore, a new condensation heat transfer correlation is proposed with mean and average deviations of 3.14 and -7.6 %, respectively.

  18. Locomotive Recalibration and Prism Adaptation of Children and Teens in Immersive Virtual Environments.

    PubMed

    Adams, Haley; Narasimham, Gayathri; Rieser, John; Creem-Regehr, Sarah; Stefanucci, Jeanine; Bodenheimer, Bobby

    2018-04-01

    As virtual reality expands in popularity, an increasingly diverse audience is gaining exposure to immersive virtual environments (IVEs). A significant body of research has demonstrated how perception and action work in such environments, but most of this work has been done studying adults. Less is known about how physical and cognitive development affect perception and action in IVEs, particularly as applied to preteen and teenage children. Accordingly, in the current study we assess how preteens (children aged 8-12 years) and teenagers (children aged 15-18 years) respond to mismatches between their motor behavior and the visual information presented by an IVE. Over two experiments, we evaluate how these individuals recalibrate their actions across functionally distinct systems of movement. The first experiment analyzed forward walking recalibration after exposure to an IVE with either increased or decreased visual flow. Visual flow during normal bipedal locomotion was manipulated to be either twice or half as fast as the physical gait. The second experiment leveraged a prism throwing adaptation paradigm to test the effect of recalibration on throwing movement. In the first experiment, our results show no differences across age groups, although subjects generally experienced a post-exposure effect of shortened distance estimation after experiencing visually faster flow and longer distance estimation after experiencing visually slower flow. In the second experiment, subjects generally showed the typical prism adaptation behavior of a throwing after-effect error. The error lasted longer for preteens than older children. Our results have implications for the design of virtual systems with children as a target audience.

  19. Modification of a prey catching response and the development of behavioral persistence in the fire-bellied toad (Bombina orientalis).

    PubMed

    Ramsay, Zachary J; Ikura, Juntaro; Laberge, Frédéric

    2013-11-01

    The present report investigated how fire-bellied toads (Bombina orientalis) modified their response in a prey catching task in which the attribution of food reward was contingent on snapping toward a visual stimulus of moving prey displayed on a computer screen. Two experiments investigated modification of the snapping response, with different intervals between the opportunity to snap at the visual stimulus and reward administration. The snapping response of unpaired controls was decreased compared with the conditioned toads when hour or day intervals were used, but intervals of 5 min produced only minimal change in snapping. The determinants of extinction of the response toward the visual stimulus were then investigated in 3 experiments. The results of the first experiment suggested that increased resistance to extinction depended mostly on the number of training trials, not on partial reinforcement or the magnitude of reinforcement during training. This was confirmed in a second experiment showing that overtraining resulted in resistance to extinction, and that the pairing of the reward with a response toward the stimulus was necessary for that effect, as opposed to pairing reward solely with the experimental context. The last experiment showed that the time elapsed between training trials also influenced extinction, but only in toads that received few training trials. Overall, the results suggest that toads learning about a prey stimulus progress from an early flexible phase, when an action can be modified by its consequences, to an acquired habit characterized by an increasingly inflexible and automatic response.

  20. Adolescents' use of sexually explicit Internet material and their sexual attitudes and behavior: Parallel development and directional effects.

    PubMed

    Doornwaard, Suzan M; Bickham, David S; Rich, Michael; ter Bogt, Tom F M; van den Eijnden, Regina J J M

    2015-10-01

    Although research has repeatedly demonstrated that adolescents' use of sexually explicit Internet material (SEIM) is related to their endorsement of permissive sexual attitudes and their experience with sexual behavior, it is not clear how linkages between these constructs unfold over time. This study combined 2 types of longitudinal modeling, mean-level development and cross-lagged panel modeling, to examine (a) developmental patterns in adolescents' SEIM use, permissive sexual attitudes, and experience with sexual behavior, as well as whether these developments are related; and (b) longitudinal directionality of associations between SEIM use on the 1 hand and permissive sexual attitudes and sexual behavior on the other hand. We used 4-wave longitudinal data from 1,132 7th through 10th grade Dutch adolescents (M(age) T1 = 13.95; 52.7% boys) and estimated multigroup models to test for moderation by gender. Mean-level developmental trajectories showed that boys occasionally and increasingly used SEIM over the 18-month study period, which co-occurred with increases in their permissive attitudes and their experience with sexual behavior. Cross-lagged panel models revealed unidirectional effects from boys' SEIM use on their subsequent endorsement of permissive attitudes, but no consistent directional effects between their SEIM use and sexual behavior. Girls showed a similar pattern of increases in experience with sexual behavior, but their SEIM use was consistently low and their endorsement of permissive sexual attitudes decreased over the 18-month study period. In contrast to boys, girls' SEIM use was not longitudinally related to their sexual attitudes and behavior. Theoretical and practical implications of these gender-specific findings are discussed. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

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