WorldWideScience

Sample records for strong extrinsic effects

  1. Extrinsic spin Hall effect in graphene

    Science.gov (United States)

    Rappoport, Tatiana

    The intrinsic spin-orbit coupling in graphene is extremely weak, making it a promising spin conductor for spintronic devices. In addition, many applications also require the generation of spin currents in graphene. Theoretical predictions and recent experimental results suggest one can engineer the spin Hall effect in graphene by greatly enhancing the spin-orbit coupling in the vicinity of an impurity. The extrinsic spin Hall effect then results from the spin-dependent skew scattering of electrons by impurities in the presence of spin-orbit interaction. This effect can be used to efficiently convert charge currents into spin-polarized currents. I will discuss recent experimental results on spin Hall effect in graphene decorated with adatoms and metallic cluster and show that a large spin Hall effect can appear due to skew scattering. While this spin-orbit coupling is small if compared with what it is found in metals, the effect is strongly enhanced in the presence of resonant scattering, giving rise to robust spin Hall angles. I will present our single impurity scattering calculations done with exact partial-wave expansions and complement the analysis with numerical results from a novel real-space implementation of the Kubo formalism for tight-binding Hamiltonians. The author acknowledges the Brazilian agencies CNPq, CAPES, FAPERJ and INCT de Nanoestruturas de Carbono for financial support.

  2. The effect of extrinsic motivation on cycle time trial performance

    NARCIS (Netherlands)

    Hulleman, M.; de Koning, J.J.; Hettinga, F.J.; Foster, C.

    2007-01-01

    PURPOSE: Athletes occasionally follow pacing patterns that seem unreasonably aggressive compared with those of prerace performances, potentially because of the motivation provided by competition. This study evaluated the effect of extrinsic motivation on cyclists' time trial performance. METHODS:

  3. The effects of extrinsic rewards on children's intrinsic motivation

    OpenAIRE

    大槻, 千秋

    1981-01-01

    An experiment was conducted with preschool children to test whether a person's intrinsic motivation in an activity may be decreased by extrinsic salient rewards in Japan like in America. Children solved some jigsaw puzzles and received assorted candies, then they were observed how long they did other jigsaw puzzles. The results showed that the effects of extrinsic rewards on intrinsic motivation in an activity varied with the subject's social background. In uptown children's intrinsic motivat...

  4. Effects of empathic paraphrasing - Extrinsic emotion regulation in social conflict

    Directory of Open Access Journals (Sweden)

    Maria eSeehausen

    2012-11-01

    Full Text Available In the present study, we investigated the effects of empathic paraphrasing as an extrinsic emotion regulation technique in social conflict. We hypothesized that negative emotions elicited by social conflict can be regulated extrinsically in a conversation by a listener following the narrator’s perspective and verbally expressing cognitive empathy.20 participants were interviewed on an ongoing or recently self-experienced social conflict. The interviewer utilized ten standardized open questions inviting participants to describe their perception of the conflict. After each of the ten descriptions, the interviewer responded by either paraphrasing or taking notes (control condition. Valence ratings pertaining to the current emotional state were assessed during the interview along with psychophysiological and voice recordings.Participants reported feeling less negative after hearing the interviewer paraphrase what they had said. In addition, we found a lower sound intensity of participants' voices when answering to questions following a paraphrase. At the physiological level, skin conductance response, as well as heart rate, was higher during paraphrasing than during taking notes, while blood volume pulse amplitude was lower during paraphrasing, indicating higher autonomic arousal.The results show that demonstrating cognitive empathy through paraphrasing can extrinsically regulate negative emotion on a short-term basis. Paraphrasing led to enhanced autonomic activation in recipients, while at the same time influencing emotional valence in the direction of feeling better. A possible explanation for these results is that being treated in an empathic manner may stimulate a more intense emotion processing helping to transform and resolve the conflict.

  5. The effect of extrinsic motivation on cycle time trial performance.

    Science.gov (United States)

    Hulleman, Michiel; De Koning, Jos J; Hettinga, Florentina J; Foster, Carl

    2007-04-01

    Athletes occasionally follow pacing patterns that seem unreasonably aggressive compared with those of prerace performances, potentially because of the motivation provided by competition. This study evaluated the effect of extrinsic motivation on cyclists' time trial performance. Well-trained recreational cyclists (N=7) completed four 1500-m laboratory time trials including a practice trial, two self-paced trials, and a trial where a monetary reward was offered. Time, total power output, power output attributable to aerobic and anaerobic metabolic sources, VO2, and HR were measured. The time required for the second, third, and last (extrinsically motivated) time trials was 133.1 +/- 2.1, 134.1 +/- 3.4, and 133.6 +/- 3.0 s, respectively, and was not different (P>0.05). There were no differences for total (396 +/- 19, 397 +/- 23, and 401 +/- 17 W), aerobic (253 +/- 12, 254 +/- 10, and 246 +/- 13 W), and anaerobic (143 +/- 14, 143 +/- 21, and 155 +/- 11 W) power output. The highest VO2 was not different over consecutive time trials (3.76 +/- 0.19, 3.73 +/- 0.16, and 3.71 +/- 0.22 L x min(-1)). When ranked by performance, without reference to the extrinsic motivation (131.9 +/- 2.4, 133.4 +/- 2.4, and 135.4 +/- 2.5 s), there was a significant difference for the first 100 m and from 100 to 300 m in power output, with a larger total power (560 +/- 102, 491 +/- 82, and 493 +/- 93; and 571 +/- 94, 513 +/- 41, and 484 +/- 88 W) and power attributable to anaerobic sources (446 +/- 100, 384 +/- 80, and 324 +/- 43; and 381 +/- 87, 383 +/- 90, and 289 +/- 91 W) for the fastest trial. Extrinsic motivation did not change the time trial performance, suggesting that 1500-m performance is extremely stable and not readily changeable with simple external motivation. The results suggest that spontaneous improvement in performance for time trials of this duration is attributable to greater early power output, which is primarily attributable to anaerobic metabolic sources.

  6. The effect of extrinsic attributes on liking of cottage cheese.

    Science.gov (United States)

    Hubbard, E M; Jervis, S M; Drake, M A

    2016-01-01

    Preference mapping studies with cottage cheese have demonstrated that cottage cheese liking is influenced by flavor, texture, curd size, and dressing content. However, extrinsic factors such as package, label claims, and brand name may also influence liking and have not been studied. The objective of this study was to evaluate the role of package attributes and brand on the liking of cottage cheese. A conjoint survey with Kano analysis (n=460) was conducted to explore the effect of extrinsic attributes (brand, label claim, milkfat content, and price) on liking. Following the survey, 150 consumers evaluated intrinsic attributes of 7 cottage cheeses with and without brand information in a 2-d crossover design. Results were evaluated by 2-way ANOVA and multivariate analyses. Milkfat content and price had the highest influence on liking by conjoint analysis. Cottage cheese with 2% milkfat and a low price was preferred. Specific label claims such as "excellent source of calcium (>10%)" were more attractive to consumers than "low sodium" or "extra creamy." Branding influenced overall liking and purchase intent for cottage cheeses to differing degrees. For national brands, acceptance scores were enhanced in the presence of the brand. An all-natural claim was more appealing than organic by conjoint analysis and this result was also confirmed with consumer acceptance testing. Findings from this study can help manufacturers, as well as food marketers, better target their products and brands with attributes that drive consumer choice. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  7. Effect of extrinsic lactic acid on fermentative hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Baghchehsaraee, Bita; Nakhla, George; Karamanev, Dimitre; Margaritis, Argyrios [Department of Chemical and Biochemical Engineering, The University of Western Ontario, 1151 Richmond Street, London, Ontario, N6A 5B9 (Canada)

    2009-03-15

    In this paper we report the effect of extrinsic lactic acid on hydrogen production from a starch-containing medium by a mixed culture. Study of the effect of addition of four metabolites, namely ethanol, lactic acid, butyric acid and acetic acid illustrated that lactic acid had a positive effect on both the maximum hydrogen production and hydrogen production rate. The addition of 10 mM lactic acid to a batch containing starch increased the hydrogen production rate and hydrogen production yield from 4.31 to 8.23 mL/h and 5.70 to 9.08 mmol H{sub 2}/g starch, respectively. This enhancement in hydrogen production rate and yield was associated with a shift from acetic acid and ethanol formation to formation of butyric acid as the predominant metabolite. The increase in hydrogen production yield was attributed to the increase in the available residual NADH for hydrogen production. When lactic acid was used as the sole carbon source, no significant hydrogen production was observed. (author)

  8. Influential Effects of Intrinsic-Extrinsic Incentive Factors on Management Performance in New Energy Enterprises.

    Science.gov (United States)

    Wang, Ping; Lu, Zhengnan; Sun, Jihong

    2018-02-08

    Background : New energy has become a key trend for global energy industry development. Talent plays a very critical role in the enhancement of new energy enterprise competitiveness. As a key component of talent, managers have been attracting more and more attention. The increase in job performance relies on, to a certain extent, incentive mechanism. Based on the Two-factor Theory, differences in influences and effects of different incentives on management performance have been checked in this paper from an empirical perspective. Methods : This paper selects the middle and low level managers in new energy enterprises as research samples and classifies the managers' performance into task performance, contextual performance and innovation performance. It uses manager performance questionnaires and intrinsic-extrinsic incentive factor questionnaires to investigate and study the effects and then uses Amos software to analyze the inner link between the intrinsic-extrinsic incentives and job performance. Results : Extrinsic incentives affect task performance and innovation performance positively. Intrinsic incentives impose active significant effects on task performance, contextual performance, and innovation performance. The intrinsic incentive plays a more important role than the extrinsic incentive. Conclusions : Both the intrinsic-extrinsic incentives affect manager performance positively and the intrinsic incentive plays a more important role than the extrinsic incentive. Several suggestions to management should be given based on these results.

  9. The effect of an oxygenating agent on chlorhexidine-induced extrinsic tooth staining: a systematic review

    NARCIS (Netherlands)

    van Maanen-Schakel, N.W.D.; Slot, D.E.; Bakker, E.W.P.; van der Weijden, G.A.

    2012-01-01

    BACKGROUND: Although chlorhexidine digluconate (CHX) is currently the most effective mouthwash for reducing plaque and gingivitis, one of its side effects is extrinsic tooth staining. Interestingly, oxygenating agents may reduce this staining. OBJECTIVE: The aim of this review was to systematically

  10. The effect of an oxygenating agent on chlorhexidine-induced extrinsic tooth staining: a systematic review

    NARCIS (Netherlands)

    van Maanen-Schakel, N. W. D.; Slot, D. E.; Bakker, E. W. P.; van der Weijden, G. A.

    2012-01-01

    Background: Although chlorhexidine digluconate (CHX) is currently the most effective mouthwash for reducing plaque and gingivitis, one of its side effects is extrinsic tooth staining. Interestingly, oxygenating agents may reduce this staining. Objective: The aim of this review was to systematically

  11. Effects of intrinsic and extrinsic factors on the diet of Bathyraja macloviana, a benthophagous skate.

    Science.gov (United States)

    Barbini, S A; Scenna, L B; Figueroa, D E; Díaz de Astarloa, J M

    2013-07-01

    The effects of intrinsic (sex, maturity stage and body size) and extrinsic (depth and region) factors on the diet of Bathyraja macloviana, in the south-west Atlantic Ocean, were evaluated using a multiple-hypothesis modelling approach. Bathyraja macloviana fed mainly on polychaetes followed by amphipods, isopods and decapods. Effects of intrinsic and extrinsic factors on diet composition of this species were found. The consumption of polychaetes had a humped relationship with total length (L(T), and isopods and decapods increased with increasing L(T). Immature individuals preyed on amphipods more heavily than mature individuals. Furthermore, region and depth had an important effect on the consumption of isopods, decapods and amphipods. Such ontogenetic changes and spatial patterns may provide insights into understanding the regulatory mechanisms of marine communities. © 2013 The Authors. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.

  12. Effects of a Baking Soda Gum on extrinsic dental stain: results of a longitudinal 4-week assessment.

    Science.gov (United States)

    Soparkar, P; Newman, M B

    2001-07-01

    An evaluation of the effects of ARM & HAMMER DENTAL CARE The Baking Soda Gum (AHDC) on extrinsic dental stain was made in 48 subjects presenting with measurable extrinsic stain. The subjects were randomized to use either the baking soda gum or a non-baking soda placebo gum for 20 minutes twice daily after lunch and dinner while brushing once daily. The procedure of limited brushing was chosen to simulate the level of hygiene normally practiced by participants entering a clinical study. After 4 weeks, the reduction in measurable extrinsic stain in the baking soda gum group was statistically significant (P = .0044) relative to baseline. Statistical analysis of the placebo gum group revealed no significant change in extrinsic stain from baseline. The magnitude of the unadjusted longitudinal reduction in extrinsic stain in the baking soda gum group was 29.7% at 4 weeks.

  13. Effects of intrinsic and extrinsic motivation on attention and memory.

    Science.gov (United States)

    Robinson, Lucy J; Stevens, Lucy H; Threapleton, Christopher J D; Vainiute, Jurgita; McAllister-Williams, R Hamish; Gallagher, Peter

    2012-10-01

    It is well recognised that motivational factors can influence neuropsychological performance. The aim of this study was to explore individual differences in intrinsic motivation and reward-seeking and the effect of these on attentional and mnemonic processes, in the presence or absence of financial incentives. Forty participants (18-35years) completed two testing sessions where the Attentional Network Test (ANT) and the Newcastle Spatial Memory Test (NSMT) were administered. After a baseline assessment, participants were re-tested after randomisation to a non-motivated (control) group or to a motivated group, where payment was contingent upon performance. Performance in the motivated group was significantly improved compared to the control group on the NSMT (condition by session; F(1,33)=4.52, p=0.041) and the ANT, with participants increasing performance to cued presentations within the alerting network (F(1,36)=5.48, p=0.025) and being less distracted by incongruent stimuli in the executive control network (F(1,36)=6.74, p=0.014). There were significant negative correlations between the 'Interest/ Enjoyment' Intrinsic Motivation Inventory subscale and both NSMT between-search errors and ANT(alerting). In the motivated group, those who had higher self-reported internal motivation were less susceptible to- or affected by- the external motivation of financial incentive. The effects of motivational factors should not be overlooked when interpreting absolute levels of performance in neuropsychological processes. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Effects of extrinsic mortality on the evolution of aging: a stochastic modeling approach.

    Directory of Open Access Journals (Sweden)

    Maxim Nikolaievich Shokhirev

    Full Text Available The evolutionary theories of aging are useful for gaining insights into the complex mechanisms underlying senescence. Classical theories argue that high levels of extrinsic mortality should select for the evolution of shorter lifespans and earlier peak fertility. Non-classical theories, in contrast, posit that an increase in extrinsic mortality could select for the evolution of longer lifespans. Although numerous studies support the classical paradigm, recent data challenge classical predictions, finding that high extrinsic mortality can select for the evolution of longer lifespans. To further elucidate the role of extrinsic mortality in the evolution of aging, we implemented a stochastic, agent-based, computational model. We used a simulated annealing optimization approach to predict which model parameters predispose populations to evolve longer or shorter lifespans in response to increased levels of predation. We report that longer lifespans evolved in the presence of rising predation if the cost of mating is relatively high and if energy is available in excess. Conversely, we found that dramatically shorter lifespans evolved when mating costs were relatively low and food was relatively scarce. We also analyzed the effects of increased predation on various parameters related to density dependence and energy allocation. Longer and shorter lifespans were accompanied by increased and decreased investments of energy into somatic maintenance, respectively. Similarly, earlier and later maturation ages were accompanied by increased and decreased energetic investments into early fecundity, respectively. Higher predation significantly decreased the total population size, enlarged the shared resource pool, and redistributed energy reserves for mature individuals. These results both corroborate and refine classical predictions, demonstrating a population-level trade-off between longevity and fecundity and identifying conditions that produce both

  15. Modeling effects of intrinsic and extrinsic rewards on the competition between striatal learning systems.

    Science.gov (United States)

    Boedecker, Joschka; Lampe, Thomas; Riedmiller, Martin

    2013-01-01

    A common assumption in psychology, economics, and other fields holds that higher performance will result if extrinsic rewards (such as money) are offered as an incentive. While this principle seems to work well for tasks that require the execution of the same sequence of steps over and over, with little uncertainty about the process, in other cases, especially where creative problem solving is required due to the difficulty in finding the optimal sequence of actions, external rewards can actually be detrimental to task performance. Furthermore, they have the potential to undermine intrinsic motivation to do an otherwise interesting activity. In this work, we extend a computational model of the dorsomedial and dorsolateral striatal reinforcement learning systems to account for the effects of extrinsic and intrinsic rewards. The model assumes that the brain employs both a goal-directed and a habitual learning system, and competition between both is based on the trade-off between the cost of the reasoning process and value of information. The goal-directed system elicits internal rewards when its models of the environment improve, while the habitual system, being model-free, does not. Our results account for the phenomena that initial extrinsic reward leads to reduced activity after extinction compared to the case without any initial extrinsic rewards, and that performance in complex task settings drops when higher external rewards are promised. We also test the hypothesis that external rewards bias the competition in favor of the computationally efficient, but cruder and less flexible habitual system, which can negatively influence intrinsic motivation and task performance in the class of tasks we consider.

  16. Effects of training in minimalist shoes on the intrinsic and extrinsic foot muscle volume.

    Science.gov (United States)

    Chen, Tony Lin-Wei; Sze, Louis K Y; Davis, Irene S; Cheung, Roy T H

    2016-07-01

    Minimalist shoes have gained popularity recently because it is speculated to strengthen the foot muscles and foot arches, which may help to resist injuries. However, previous studies provided limited evidence supporting the link between changes in muscle size and footwear transition. Therefore, this study sought to examine the effects of minimalist shoes on the intrinsic and extrinsic foot muscle volume in habitual shod runners. The relationship between participants' compliance with the minimalist shoes and changes in muscle õvolume was also evaluated. Twenty habitual shod runners underwent a 6-month self-monitoring training program designed for minimalist shoe transition. Another 18 characteristics-matched shod runners were also introduced with the same program but they maintained running practice with standard shoes. Runners were monitored using an online surveillance platform during the program. We measured overall intrinsic and extrinsic foot muscle volume before and after the program using MRI scans. Runners in the experimental group exhibited significantly larger leg (P=0.01, Cohen's d=0.62) and foot (Pshoes and changes in leg muscle volume (r=0.51; P=0.02). Habitual shod runners who transitioned to minimalist shoes demonstrated significant increase in leg and foot muscle volume. Additionally, the increase in leg muscle volume was significantly correlated associated with the compliance of minimalist shoe use. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Early-warning signals of critical transition: Effect of extrinsic noise

    Science.gov (United States)

    Qin, Shanshan; Tang, Chao

    2018-03-01

    Complex dynamical systems often have tipping points and exhibit catastrophic regime shift. Despite the notorious difficulty of predicting such transitions, accumulating studies have suggested the existence of generic early-warning signals (EWSs) preceding upcoming transitions. However, previous theories and models were based on the effect of the intrinsic noise (IN) when a system is approaching a critical point, and did not consider the pervasive environmental fluctuations or the extrinsic noise (EN). Here, we extend previous theory to investigate how the interplay of EN and IN affects EWSs. Stochastic simulations of model systems subject to both IN and EN have verified our theory and demonstrated that EN can dramatically alter and diminish the EWS. This effect is stronger with increasing amplitude and correlation time scale of the EN. In the presence of EN, the EWS can fail to predict or even give a false alarm of critical transitions.

  18. Effect of toothbrushing on shade and surface roughness of extrinsically stained pressable ceramics.

    Science.gov (United States)

    Garza, Lessly A; Thompson, Geoffrey; Cho, Seok-Hwan; Berzins, David W

    2016-04-01

    The effect of toothbrushing on extrinsically stained pressable ceramic materials is unknown. The purpose of this in vitro study was to investigate the effects of toothbrushing on the shade and surface roughness of extrinsically stained, pressable ceramics. Two materials, leucite-based (IPS Empress Esthetic [EE]; Ivoclar Vivadent AG) and lithium disilicate-based ceramic (IPS e.max Press [EP]; Ivoclar Vivadent AG), were studied. For each material, 24 disk-shaped specimens, 10 mm (diameter)×3 mm (height) were fabricated. Three different methods (n=8) of applying extrinsic stains were performed on each material: glazed only (G, control group); stained then glazed (SG); and stained and glazed together (T). The specimens were brushed with a multistation brushing machine under a load of 1.96 N at a rate of 90 strokes per minute with a soft and straight toothbrush (Oral-B #35) and a 1:1 toothpaste and distilled water slurry. Shade and roughness were measured at baseline and at 72, 144, 216, and 288 hours, which is equivalent to 3, 6, 9, and 12 years of simulated toothbrushing for 2 minutes twice a day. A repeated measures ANOVA with staining technique as a fixed factor was used to evaluate shade and roughness (α=.05). For EE groups, no significant change was found after 12 years of simulated toothbrushing regarding shade and surface roughness, irrespective of staining techniques (P>.05). However, EP groups demonstrated a significant shade change and an increase in surface roughness after 12 years of simulated toothbrushing. Shade change was found to depend on the method of applying stain. For the EP-SG technique, a significant shade change was observed only at the 9- to 12-year interval (P=.047). However, the EP-T technique demonstrated a significant difference in shade between baseline and 3 years (P=.005) and in the 6- to 9-year interval (P=.005). Surface roughness was only significantly affected at baseline and 3 years for the EP-T group (P=.005). For the shade and

  19. Effects of local extrinsic mortality rate, crime and sex ratio on preventable death in Northern Ireland.

    Science.gov (United States)

    Uggla, Caroline; Mace, Ruth

    2015-09-03

    Individual investment in health varies greatly within populations and results in significant differences in the risk of preventable death. Life history theory predicts that individuals should alter their investment in health (somatic maintenance) in response to ecological cues that shift the perceived fitness payoffs to such investments. However, previous research has failed to isolate the effects of different ecological factors on preventable death, and has often relied on macro-level data without individual controls. Here, we test some key predictions concerning the local ecology-that higher extrinsic mortality rate (EMR), crime rate and mate-scarcity (male/female-biased sex ratio) at the ward-level-will be associated with a higher risk of preventable death. We use census-based data from Northern Ireland (n = 927 150) on preventable death during an 8.7-year period from the 2001 Census and run Cox regressions for (i) accident/suicide or alcohol-related death and (ii) deaths from preventable diseases, for men and women separately, controlling for a wide range of individual variables. We find evidence of ward-level EMR and crime rate being positively associated with preventable death among men, particularly men with low socioeconomic position. There was a tentative relationship between male-biased sex ratio and preventable death among women, but not among men. Both behaviours that might lead to 'risky' death and health neglect might be adaptive responses to local ecologies. Efforts to reduce crime might be as effective as those to reduce extrinsic mortality, and both could have positive effects on various health behaviours. © The Author(s) 2015. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

  20. In vitro assessment of the effectiveness of whitening dentifrices for the removal of extrinsic tooth stains

    Directory of Open Access Journals (Sweden)

    Débora Alves Nunes Leite Lima

    2008-06-01

    Full Text Available This in vitro study evaluated the effectiveness of whitening dentifrices for the removal of extrinsic tooth stains. Twenty dental blocks (4 x 4 mm, including enamel and dentine, removed from freshly extracted bovine incisors, were randomly divided into 4 groups: G1 - distilled water, G2 - Colgate, G3 - Crest Extra Whitening and G4 - Rapid White. In all specimens, the dentin was covered with colorless nail polish, and the enamel was left exposed. Next, the specimens were immersed in a solution of black tea, which was changed every 24 h, for a period of 6 days. After this period, a photo-reflectance reading was taken (Time 1 with a spectrometer. The stained specimens were then submitted to linear brushing movements (5,000 cycles using brushes (Oral B-Soft coupled to an automatic toothbrushing machine, under a static axial load of 200 g and with a speed of 4 movements/second, at 37°C, with the dentifrice or water being injected every 60 s. When toothbrushing ended, a second photo-reflectance reading was taken (Time 2. The results were submitted to two-criteria analysis of variance (ANOVA and to the Tukey test ( = 0.05. When the two times for a same group were compared, Time 2 presented the highest reflectance values with statistical difference only for G3 and G4. Among the dentifrices tested, only the Rapid White group differed from the control group, presenting the highest reflectance values. Only the whitening dentifrice Rapid White was effective for the removal of extrinsic stains.

  1. The detrimental effects of extrinsic reinforcement on “Intrinsic motivation”

    OpenAIRE

    Dickinson, Alyce M.

    1989-01-01

    Extrinsic consequences have been criticized on the grounds that they decrease intrinsic motivation or internally initiated behavior. Two popular rationales for this criticism, Lepper's overjustification hypothesis (1981) and Deci's motivational theory (Deci & Ryan, 1985), are reviewed and the criticism is then redefined behaviorally. “Intrinsically controlled” behavior is defined as behavior maintained by response-produced reinforcers, and the question concerning extrinsic consequences is thu...

  2. Negative magnetoresistance in Weyl semimetals NbAs and NbP: Intrinsic chiral anomaly and extrinsic effects

    Science.gov (United States)

    Li, Yupeng; Wang, Zhen; Li, Pengshan; Yang, Xiaojun; Shen, Zhixuan; Sheng, Feng; Li, Xiaodong; Lu, Yunhao; Zheng, Yi; Xu, Zhu-An

    2017-06-01

    Chiral anomaly-induced negative magnetoresistance (NMR) has been widely used as critical transport evidence for the existence of Weyl fermions in topological semimetals. In this mini-review, we discuss the general observation of NMR phenomena in non-centrosymmetric NbP and NbAs. We show that NMR can arise from the intrinsic chiral anomaly of Weyl fermions and/or extrinsic effects, such as the superimposition of Hall signals; field-dependent inhomogeneous current flow in the bulk, i.e., current jetting; and weak localization (WL) of coexistent trivial carriers. The WL-controlled NMR is heavily dependent on sample quality and is characterized by a pronounced crossover from positive to negative MR growth at elevated temperatures, resulting from the competition between the phase coherence time and the spin-orbital scattering constant of the bulk trivial pockets. Thus, the correlation between the NMR and the chiral anomaly need to be scrutinized without the support of complimentary techniques. Because of the lifting of spin degeneracy, the spin orientations of Weyl fermions are either parallel or antiparallel to the momentum, which is a unique physical property known as helicity. The conservation of helicity provides strong protection for the transport of Weyl fermions, which can only be effectively scattered by magnetic impurities. Chemical doping with magnetic and non-magnetic impurities is thus more convincing than the NMR method for detecting the existence of Weyl fermions.

  3. Extrinsic morphology of graphene

    International Nuclear Information System (INIS)

    Li, Teng

    2011-01-01

    Graphene is intrinsically non-flat and corrugates randomly. Since the corrugating physics of atomically thin graphene is strongly tied to its electronics properties, randomly corrugating morphology of graphene poses a significant challenge to its application in nanoelectronic devices for which precise (digital) control is the key. Recent studies revealed that the morphology of substrate-supported graphene is regulated by the graphene–substrate interaction, thus is distinct from the random intrinsic morphology of freestanding graphene. The regulated extrinsic morphology of graphene sheds light on new pathways to fine tune the properties of graphene. To guide further research to explore these fertile opportunities, this paper reviews recent progress on modeling and experimental studies of the extrinsic morphology of graphene under a wide range of external regulation, including two-dimensional and one-dimensional substrate surface features and one-dimensional and zero-dimensional nanoscale scaffolds (e.g. nanowires and nanoparticles)

  4. Effects of extrinsic point defects in phosphorene: B, C, N, O, and F adatoms

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Gaoxue, E-mail: gaoxuew@mtu.edu, E-mail: pandey@mtu.edu, E-mail: shashi.p.karna.civ@mail.mil; Pandey, Ravindra, E-mail: gaoxuew@mtu.edu, E-mail: pandey@mtu.edu, E-mail: shashi.p.karna.civ@mail.mil [Department of Physics, Michigan Technological University, Houghton, Michigan 49931 (United States); Karna, Shashi P., E-mail: gaoxuew@mtu.edu, E-mail: pandey@mtu.edu, E-mail: shashi.p.karna.civ@mail.mil [U.S. Army Research Laboratory, Weapons and Materials Research Directorate, ATTN: RDRL-WM, Aberdeen Proving Ground, Maryland 21005-5069 (United States)

    2015-04-27

    Phosphorene is emerging as a promising 2D semiconducting material with a direct band gap and high carrier mobility. In this paper, we examine the role of the extrinsic point defects including surface adatoms in modifying the electronic properties of phosphorene using density functional theory. The surface adatoms considered are B, C, N, O, and F with a [He] core electronic configuration. Our calculations show that B and C, with electronegativity close to P, prefer to break the sp{sup 3} bonds of phosphorene and reside at the interstitial sites in the 2D lattice by forming sp{sup 2} like bonds with the native atoms. On the other hand, N, O, and F, which are more electronegative than P, prefer the surface sites by attracting the lone pairs of phosphorene. B, N, and F adsorption will also introduce local magnetic moment to the lattice. Moreover, B, C, N, and F adatoms will modify the band gap of phosphorene, yielding metallic transverse tunneling characters. Oxygen does not modify the band gap of phosphorene, and a diode like tunneling behavior is observed. Our results therefore offer a possible route to tailor the electronic and magnetic properties of phosphorene by the adatom functionalization and provide the physical insights of the environmental sensitivity of phosphorene, which will be helpful to experimentalists in evaluating the performance and aging effects of phosphorene-based electronic devices.

  5. Effects of extrinsic point defects in phosphorene: B, C, N, O and F Adatoms

    OpenAIRE

    Wang, Gaoxue; Pandey, Ravindra; Karna, Shashi P.

    2015-01-01

    Phosphorene is emerging as a promising 2D semiconducting material with a direct band gap and high carrier mobility. In this paper, we examine the role of the extrinsic point defects including surface adatoms in modifying the electronic properties of phosphorene using density functional theory. The surface adatoms considered are B, C, N, O and F with a [He] core electronic configuration. Our calculations show that B and C, with electronegativity close to P, prefer to break the sp3 bonds of pho...

  6. The effects of various gate oxidation conditions on intrinsic and radiation-induced extrinsic charged defects and neutral electron traps

    International Nuclear Information System (INIS)

    Walters, M.; Reisman, A.

    1990-01-01

    In this paper the influence of the oxidation temperature, ambient atmosphere, and oxidation rate on intrinsic and Al Kα x-ray radiation-induced extrinsic gate oxide defect levels in insulated-gate field effect transistors (IGFETs) is studied. Using optically assisted electron injection into n-channel polysilicon-gated IGFETs, neutral electron trap and fixed negative charge defect densities were measured, in addition to the fixed positive charge density. The results indicate that radiation-induced defect densities in the gate oxide decrease with increasing oxidation temperature in the 800 degrees C to 1000 degrees C range, and are lower for dry/wet/dry oxides than for dry oxides when the oxidation temperature is below 950 degrees C, but higher when the oxidation temperature is above 950 degrees C. The oxidation rate had no effect on defect levels in dry oxides grown at 1000 degrees CX, while at an oxidation temperature of 800 degrees C, the extrinsic defect densities were observed to increase when the oxidation rate was decreased. In all cases, the radiation-induced fixed positive charge and neutral electron trap defect densities were observed to be dependent upon the gate oxidation conditions in the same fashion

  7. Cold Nuclear Matter Effects on J/psi Production: Intrinsic and Extrinsic Transverse Momentum Effects

    Energy Technology Data Exchange (ETDEWEB)

    Ferreiro, E.G.; /Santiago de Compostela U.; Fleuret, F.; /Ecole Polytechnique; Lansberg, J.P.; /Heidelberg U.; Rakotozafindrabe, A.; /SPhN, DAPNIA, Saclay

    2010-08-26

    Cold nuclear matter effects on J/{psi} production in proton-nucleus and nucleus-nucleus collisions are evaluated taking into account the specific J/{psi}-production kinematics at the partonic level, the shadowing of the initial parton distributions and the absorption in the nuclear matter. We consider two different parton processes for the c{bar c}-pair production: one with collinear gluons and a recoiling gluon in the final state and the other with initial gluons carrying intrinsic transverse momentum. Our results are compared to RHIC observables. The smaller values of the nuclear modification factor R{sub AA} in the forward rapidity region (with respect to the mid rapidity region) are partially explained, therefore potentially reducing the need for recombination effects.

  8. Work Motivation and the Negative Effects of Extrinsic Rewards: A Reward With Implications for Theory and Practice

    Science.gov (United States)

    Notz, William W.

    1975-01-01

    Summarizes and discusses findings on two hypotheses predicting interaction between intrinsic and extrinsic motivation: extrinsic rewards are those which provide satisfaction independent of the actual activity itself and are controlled by someone other than the employee, whereas intrinsic rewards are those over which the employee has a high degree…

  9. Finding quantum effects in strong classical potentials

    Science.gov (United States)

    Hegelich, B. Manuel; Labun, Lance; Labun, Ou Z.

    2017-06-01

    The long-standing challenge to describing charged particle dynamics in strong classical electromagnetic fields is how to incorporate classical radiation, classical radiation reaction and quantized photon emission into a consistent unified framework. The current, semiclassical methods to describe the dynamics of quantum particles in strong classical fields also provide the theoretical framework for fundamental questions in gravity and hadron-hadron collisions, including Hawking radiation, cosmological particle production and thermalization of particles created in heavy-ion collisions. However, as we show, these methods break down for highly relativistic particles propagating in strong fields. They must therefore be improved and adapted for the description of laser-plasma experiments that typically involve the acceleration of electrons. Theory developed from quantum electrodynamics, together with dedicated experimental efforts, offer the best controllable context to establish a robust, experimentally validated foundation for the fundamental theory of quantum effects in strong classical potentials.

  10. Long-term protective effect of surface sealants against erosive wear by intrinsic and extrinsic acids.

    Science.gov (United States)

    Wegehaupt, Florian J; Tauböck, Tobias T; Sener, Beatrice; Attin, Thomas

    2012-05-01

    To test sealants to prevent erosive tooth wear caused by extrinsic and intrinsic acids under long-term exposition. 144 bovine enamel samples were randomly allocated to twelve groups (1-12). Samples of groups 1, 5 and 9 remained unsealed (positive controls), 2, 6 and 10 were sealed with Silicon Seal Nano Mix and 3, 7 and 11 with Seal&Protect. Groups 4, 8 and 12 were sealed with flowable composite (negative controls). Groups 1-4 were immersed in artificial saliva, 5-8 in hydrochloric acid and groups 9-12 in citric acid for 28 days, respectively. After 1, 2, 4, 7, 11, 14, 21 and 28 days, solutions were renewed and enamel wear was quantified by assignation of (32)P in the solutions. In all immersion solutions, lowest mineral loss was observed for the negative controls whilst highest loss was observed for unsealed positive controls. In artificial saliva and citric acid, the loss from samples sealed with Seal&Protect was not significantly different compared with negative controls whilst loss in groups sealed with Silicon Seal Nano Mix was significantly higher. In hydrochloric acid, loss from samples sealed with Seal&Protect was not different compared with that of negative controls up to 4 days. Except day 1, the mineral loss in the Seal&Protect group was significantly lower compared with that of the Silicon Seal Nano Mix group. The tested resin based surface sealant is able to significantly reduce the erosive demineralisation of enamel caused by hydrochloric and citric acid even under long-term exposition. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Beyond Technology, an Analysis of the Perceived Impact of Transformational Leadership and Contingent Rewards as Extrinsic Motivation on Virtual Team Member Satisfaction and Leadership Effectiveness: A Quantitative Study

    Science.gov (United States)

    Mawanda, Haruna Juko

    2012-01-01

    The primary purpose of this nonexperimental, correlational, and descriptive quantitative study research was to gain an empirical understanding of the effects of transformational leadership and contingent reward as extrinsic motivation on employee satisfaction with leadership and leadership effectiveness in virtual team workplace environments.…

  12. Wormhole effect in a strong topological insulator

    Science.gov (United States)

    Rosenberg, G.; Guo, H.-M.; Franz, M.

    2010-07-01

    An infinitely thin solenoid carrying magnetic flux Φ (a “Dirac string”) inserted into an ordinary band insulator has no significant effect on the spectrum of electrons. In a strong topological insulator, remarkably, such a solenoid carries protected gapless one-dimensional fermionic modes when Φ=hc/2e . These modes are spin-filtered and represent a distinct bulk manifestation of the topologically nontrivial insulator. We establish this “wormhole” effect by both general qualitative considerations and by numerical calculations within a minimal lattice model. We also discuss the possibility of experimental observation of a closely related effect in artificially engineered nanostructures.

  13. Reading Amount as a Mediator of the Effects of Intrinsic and Extrinsic Reading Motivation on Reading Comprehension

    Science.gov (United States)

    Schaffner, Ellen; Schiefele, Ulrich; Ulferts, Hannah

    2013-01-01

    This study examined the role of reading amount as a mediator of the effects of intrinsic and extrinsic reading motivation on higher order reading comprehension (comprised of paragraph-and passage-level comprehension) in a sample of 159 fifth-grade elementary students. A positive association between intrinsic reading motivation and reading amount…

  14. Effects of Extrinsic and Intrinsic Proton Activity on The Mechanism of Oxygen Reduction in Ionic Liquids

    Science.gov (United States)

    Zeller, Robert August

    Mechanisms for oxygen reduction are proposed for three distinct cases covering two ionic liquids of fundamentally different archetypes and almost thirty orders of magnitude of proton activity. Proton activity is treated both extrinsically by varying the concentration and intrinsically by selecting proton donors with a wide range of aqueous pKa values. The mechanism of oxygen reduction in ionic liquids is introduced by way of the protic ionic liquid (pIL) triethylammonium triflate (TEATf) which shares some similarities with aqueous acid solutions. Oxygen reduction in TEATf begins as the one electron rate limited step to form superoxide, O2 *-, which is then rapidly protonated by the pIL cation forming the perhydroxyl radical, HO2*. The perhydroxyl radical is further reduced to peroxidate (HO2-) and hydrogen peroxide in proportions in accordance with their pKa. The reaction does not proceed beyond this point due to the adsorption of the conjugate base triethylammine interfering with the disproportionation of hydrogen peroxide. This work demonstrates that this mechanism is consistent across Pt, Au, Pd, and Ag electrodes. Two related sets of experiments were performed in the inherently aprotic ionic liquid 1-butyl-2,3-dimethylimidazolium triflate (C4dMImTf). The first involved the titration of acidic species of varying aqueous pKa into the IL while monitoring the extent of oxygen reduction as a function of pKa and potential on Pt and glassy carbon (GC) electrodes. These experiments confirmed the greater propensity of Pt to reduce oxygen by its immediate and abrupt transition from one electron reduction to four electron reduction, while oxygen reduction on GC gradually approaches four electron reduction as the potentials were driven more cathodic. The potential at which oxygen reduction initiates shows general agreement with the Nernst equation and the acid's tabulated aqueous pKa value, however at the extremely acidic end, a small deviation is observed. The second set

  15. Bridging the gap between extrinsic and intrinsic motivation in the cognitive remediation of schizophrenia.

    Science.gov (United States)

    Silverstein, Steven M

    2010-09-01

    An important development in cognitive remediation of schizophrenia is a focus on motivation. However, following a distinction between the concepts of intrinsic motivation (IM) and extrinsic motivation, discussions of IM-based methods have downplayed or misrepresented the role that extrinsic rewards can, and actually do, serve to promote positive treatment outcomes in cognitive remediation. Therefore, the purpose of this article is to explore the rationale for using techniques incorporating extrinsic rewards into cognitive treatment of people with schizophrenia. To do this, evidence is presented on each of the following points: (1) there is a long history of research demonstrating that delivery of extrinsic reward is associated with positive outcomes in both behavioral and cognitive rehabilitation; (2) basic human brain systems respond strongly to tangible rewards, and this can directly enhance attention, working memory, and other cognitive functions; (3) nearly all data on the negative effects of extrinsic reward on IM have come from studies of healthy children and adults in school or work settings who have adequate IM for target tasks; these findings do not generalize well to cognitive remediation settings for people with schizophrenia, who often have abnormally low levels of IM and low base rates of attentive behaviors; and (4) in real-world situations, cognitive remediation interventions already utilize a combination of intrinsic and extrinsic reinforcers. Future studies are needed to clarify state and trait factors responsible for individual differences in the extent to which extrinsic rewards are necessary to set the conditions under which IM can develop.

  16. Effectiveness of a new dentifrice with baking soda and peroxide in removing extrinsic stain and whitening teeth.

    Science.gov (United States)

    Ghassemi, A; Hooper, W; Vorwerk, L; Domke, T; DeSciscio, P; Nathoo, S

    2012-01-01

    The primary purpose of this randomized, controlled, six-week clinical trial was to determine the effectiveness and safety of a new whitening dentifrice in removing extrinsic tooth stain and whitening teeth. An additional two-week exploratory study was conducted to determine whether the whitening or stain-prevention activity of the dentifrice would persist following cessation of use. In the first study (Phase I), one-hundred and forty-six qualifying subjects were randomly assigned to either a sodium bicarbonate whitening dentifrice group (Arm & Hammer Advance White Extreme Whitening Baking Soda and Peroxide Toothpaste) or a silica-based negative control dentifrice group, and brushed twice daily with their assigned dentifrice for six weeks. Tooth shade on the labial surfaces of the eight incisors was assessed using a Vita Classic shade guide, and extrinsic tooth stain was scored using a Modified Lobene Stain Index (MLSI) at baseline, week 4, and week 6. In Phase II (after the week 6 examination), volunteers from the Arm & Hammer whitening dentifrice group were randomly assigned to continue using the whitening dentifrice or to use the negative control dentifrice twice daily for two weeks. The six-week shade and stain index scores served as the baseline for this exploratory phase and were rescored after two weeks. The whitening dentifrice group had statistically significant (p < 0.0001) mean shade score reductions of 1.82 and 2.57 from baseline to weeks 4 and 6, respectively. For the same periods, the negative control dentifrice group was virtually unchanged from baseline. For tooth stain, the MLSI total mean scores for the whitening dentifrice group showed statistically significant (p < 0.0001) decreases from baseline of 1.42 (41.6%) and 2.11 (61.6%) at weeks 4 and 6, respectively. In contrast, the negative control dentifrice group had a MLSI reduction of 0.07 at week 4 and a 0.06 increase at week 6. Between-group analyses using baseline-adjusted ANCOVA showed the

  17. Strong curvature effects in Neumann wave problems

    DEFF Research Database (Denmark)

    Willatzen, Morten; Pors, A.; Gravesen, Jens

    2012-01-01

    Waveguide phenomena play a major role in basic sciences and engineering. The Helmholtz equation is the governing equation for the electric field in electromagnetic wave propagation and the acoustic pressure in the study of pressure dynamics. The Schro¨dinger equation simplifies to the Helmholtz...... equation for a quantum-mechanical particle confined by infinite barriers relevant in semiconductor physics. With this in mind and the interest to tailor waveguides towards a desired spectrum and modal pattern structure in classical structures and nanostructures, it becomes increasingly important...... to understand the influence of curvature effects in waveguides. In this work, we demonstrate analytically strong curvature effects for the eigenvalue spectrum of the Helmholtz equation with Neumann boundary conditions in cases where the waveguide cross section is a circular sector. It is found that the linear...

  18. Effects of Extrinsic Rewards on Intrinsic Motivation: Improving Learning in the Elementary Classroom.

    Science.gov (United States)

    Zbrzezny, Ruth A.

    A literature review focused on ways for teachers to increase students' motivation. A total of 37 annotations were organized in terms of positive and negative effects of rewards on students' motivation, the issue of whether negative effects of rewards can be manipulated to have a positive effect, and suggestions for the classroom teacher on the use…

  19. Strong curvature effects in Neumann wave problems

    International Nuclear Information System (INIS)

    Willatzen, M.; Pors, A.; Gravesen, J.

    2012-01-01

    Waveguide phenomena play a major role in basic sciences and engineering. The Helmholtz equation is the governing equation for the electric field in electromagnetic wave propagation and the acoustic pressure in the study of pressure dynamics. The Schrödinger equation simplifies to the Helmholtz equation for a quantum-mechanical particle confined by infinite barriers relevant in semiconductor physics. With this in mind and the interest to tailor waveguides towards a desired spectrum and modal pattern structure in classical structures and nanostructures, it becomes increasingly important to understand the influence of curvature effects in waveguides. In this work, we demonstrate analytically strong curvature effects for the eigenvalue spectrum of the Helmholtz equation with Neumann boundary conditions in cases where the waveguide cross section is a circular sector. It is found that the linear-in-curvature contribution originates from parity symmetry breaking of eigenstates in circular-sector tori and hence vanishes in a torus with a complete circular cross section. The same strong curvature effect is not present in waveguides subject to Dirichlet boundary conditions where curvature contributions contribute to second-order in the curvature only. We demonstrate this finding by considering wave propagation in a circular-sector torus corresponding to Neumann and Dirichlet boundary conditions, respectively. Results for relative eigenfrequency shifts and modes are determined and compared with three-dimensional finite element method results. Good agreement is found between the present analytical method using a combination of differential geometry with perturbation theory and finite element results for a large range of curvature ratios.

  20. Effects of Personal Control, Extrinsic Rewards, and Competence on Intrinsic Motivation.

    Science.gov (United States)

    1978-07-01

    This report investigated three of the possible determinants of intrinsic motivation identified by Pritchard and Montagno (1978) in an earlier phase...literature review revealed that the effects of personal control on intrinsic motivation had never been evaluated, that a suggested interaction of... intrinsic motivation had produced conflicting results and conclusions. Further, most of the research reviewed had been conducted under laboratory

  1. Modelling the effect of temperature change on the extrinsic incubation period and reproductive number of Plasmodium falciparum in Malaysia.

    Science.gov (United States)

    Chua, T H

    2012-03-01

    According to the report of the Intergovernmental Panel on Climate Change (IPCC), Malaysia will experience an increase of 3-5°C in the future. As the development of the malaria parasite, Plasmodium falciparum, is sensitive to temperature, we investigated, using computer models, the effect of increase of 3º and 5ºC on the possible changes in the epidemiology of malaria transmission of P. falciparum in Malaysia. Four environmentally different locations were selected: Kuala Lumpur (KL), Cameron Highlands (CH), Kota Kinabalu (KK) and Kinabalu Park (KP). The extrinsic incubation period (EIP) was estimated using hourly temperatures and the mean daily temperatures. The EIP values estimated using the mean daily temperature were lower than those computed from hourly temperatures in warmer areas (KL, KK), but higher in the cooler areas (CH, KP). The computer simulations also indicated that the EIP will be decreased if the temperature was raised by 3º or 5ºC, with the effect more pronounced for the greater temperature increase, and for the cooler places. The vector cohort that is still alive at a time to transmit malaria (s(EIP)) also increased when the temperature was raised, with the increase more pronounced in the cooler areas. This study indicates an increase in temperature will have more significant effect in shortening the EIP in a cooler place (eg CH, KP), resulting in a greater s(EIP), and consequently increasing the transmission intensity and malaria risk. A temperature increase arising from the global climate change will likely affect the epidemiology of malaria in Malaysia, especially in the cooler areas.

  2. Orbital magnetic moment and extrinsic spin Hall effect for iron impurities in gold

    Czech Academy of Sciences Publication Activity Database

    Shick, Alexander; Kolorenč, Jindřich; Janiš, Václav; Lichtenstein, A.I.

    2011-01-01

    Roč. 84, č. 11 (2011), "113112-1"-"113112-4" ISSN 1098-0121 R&D Projects: GA ČR(CZ) GAP204/10/0330; GA AV ČR IAA100100912 Institutional research plan: CEZ:AV0Z10100520 Keywords : spin Hall effect * XMCD Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.691, year: 2011 http://prb.aps.org/abstract/PRB/v84/i11/e113112

  3. Intrinsic and extrinsic mortality reunited

    DEFF Research Database (Denmark)

    Koopman, Jacob J E; Wensink, Maarten J; Rozing, Maarten P

    2015-01-01

    Intrinsic and extrinsic mortality are often separated in order to understand and measure aging. Intrinsic mortality is assumed to be a result of aging and to increase over age, whereas extrinsic mortality is assumed to be a result of environmental hazards and be constant over age. However......, allegedly intrinsic and extrinsic mortality have an exponentially increasing age pattern in common. Theories of aging assert that a combination of intrinsic and extrinsic stressors underlies the increasing risk of death. Epidemiological and biological data support that the control of intrinsic as well...... as extrinsic stressors can alleviate the aging process. We argue that aging and death can be better explained by the interaction of intrinsic and extrinsic stressors than by classifying mortality itself as being either intrinsic or extrinsic. Recognition of the tight interaction between intrinsic and extrinsic...

  4. Effectiveness of a mouthrinse containing active ingredients in addition to chlorhexidine and triclosan compared with chlorhexidine and triclosan rinses on plaque, gingivitis, supragingival calculus and extrinsic staining.

    Science.gov (United States)

    Kumar, S; Patel, S; Tadakamadla, J; Tibdewal, H; Duraiswamy, P; Kulkarni, S

    2013-02-01

    To assess the effectiveness of three different mouthrinses--chlorhexidine, triclosan + sodium fluoride and chlorhexidine + triclosan + sodium fluoride + zinc chloride--on plaque, calculus, gingivitis and stains and to evaluate the occurrence of adverse effects with these three treatments. Forty-eight healthy subjects participated in a double-blind, randomized, parallel experiment and were randomly allocated to any one of the three experimental mouthrinses: group A (0.2% chlorhexidine (CHX) gluconate), group B (0.03% triclosan + 0.025% sodium fluoride (NaF) + 12% ethyl alcohol) or group C (0.2% CHX + 0.3% triclosan + 0.3% NaF + 0.09% Zn chloride (ZnCl(2)). All the subjects were assessed for gingivitis, plaque, supragingival calculus and extrinsic stains at baseline and at the end of the 21-day experimental period. There was a significant difference (P = 0.046) in the effectiveness for the prevention of gingivitis and plaque, with subjects of group A and group C presenting least and highest gingival and plaque scores, respectively. Significant differences (P = 0.03) were observed for the accumulation of supragingival calculus where the deposition of calculus in group A was nearly double that of the group B, and group B was most effective in the prevention of supragingival calculus. Highest deposition of extrinsic stains was in the group A followed by group C and group B. There was no significant difference between the three treatments for adverse events' occurrence. CHX mouthrinse was most effective in controlling plaque and gingivitis but caused greatest deposition of extrinsic stains. Supragingival calculus deposition was least in triclosan + NaF group followed by CHX + triclosan + NaF + ZnCl(2) and CHX. More than half of the subjects reported adverse events during the experimental phase. © 2012 John Wiley & Sons A/S.

  5. Strong crystal size effect on deformation twinning

    DEFF Research Database (Denmark)

    Yu, Qian; Shan, Zhi-Wei; Li, Ju

    2010-01-01

    find that the stress required for deformation twinning increases drastically with decreasing sample size of a titanium alloy single crystal7, 8, until the sample size is reduced to one micrometre, below which the deformation twinning is entirely replaced by less correlated, ordinary dislocation...... plasticity. Accompanying the transition in deformation mechanism, the maximum flow stress of the submicrometre-sized pillars was observed to saturate at a value close to titanium’s ideal strength9, 10. We develop a ‘stimulated slip’ model to explain the strong size dependence of deformation twinning....... The sample size in transition is relatively large and easily accessible in experiments, making our understanding of size dependence11, 12, 13, 14, 15, 16, 17 relevant for applications....

  6. Mode power distribution effect in white-light multimode fiber extrinsic Fabry-Perot interferometric sensor systems.

    Science.gov (United States)

    Han, Ming; Wang, Anbo

    2006-05-01

    Theoretical and experimental results have shown that mode power distribution (MPD) variations could significantly vary the phase of spectral fringes from multimode fiber extrinsic Fabry-Perot interferometric (MMF-EFPI) sensor systems, owing to the fact that different modes introduce different extra phase shifts resulting from the coupling of modes reflected at the second surface to the lead-in fiber end. This dependence of fringe pattern on MPD could cause measurement errors in signal demodulation methods of white-light MMF-EFPI sensors that implement the phase information of the fringes.

  7. Strong coupling effects in hybrid plexitonic systems

    Science.gov (United States)

    Melnikau, Dzmitry; Esteban, Ruben; Govyadinov, Alexander A.; Savateeva, Diana; Simon, Thomas; Sánchez-Iglesias, Ana; Grzelczak, Marek; Schmidt, Mikolaj K.; Urban, Alexander S.; Liz-Marzán, Luis M.; Feldmann, Jochen; Aizpurua, Javier; Rakovich, Yury P.

    2017-08-01

    We investigated the interactions between localized plasmons in gold nanorods and excitons in J-aggregates and were able to track an anticrossing behavior of the hybridized modes both in the extinction and in the photoluminescence spectra of this hybrid system. We identified the nonlinear optical behavior of this system by transient absorption spectroscopy. Finally using magnetic circular dichroism spectroscopy we showed that nonmagnetic organic molecules exhibit magnetooptical response due to binding to a plasmonic nanoparticles. In our experiments we also studied the effect of detuning as well as the effect of off- and on resonance excitation on the hybrid states

  8. Recollection and unitization in associating actors with extrinsic and intrinsic motions.

    Science.gov (United States)

    Kersten, Alan W; Earles, Julie L; Berger, Johanna D

    2015-04-01

    Four experiments provide evidence for a distinction between 2 different kinds of motion representations. Extrinsic motions involve the path of an object with respect to an external frame of reference. Intrinsic motions involve the relative motions of the parts of an object. This research suggests that intrinsic motions are represented conjointly with information about the identities of the actors who perform them, whereas extrinsic motions are represented separately from identity information. Experiment 1 demonstrated that participants remembered which actor had performed a particular intrinsic motion better than they remembered which actor had performed a particular extrinsic motion. Experiment 2 replicated this effect with incidental encoding of actor information, suggesting that encoding intrinsic motions leads one to automatically encode identity information. The results of Experiments 3 and 4 were fit by Yonelinas's (1999) source-memory model to quantify the contributions of familiarity and recollection to memory for the actors who carried out the intrinsic and extrinsic motions. Successful performance with extrinsic motion items in Experiment 3 required participants to remember in which scene contexts an actor had appeared, whereas successful performance in Experiment 4 required participants to remember the exact path taken by an actor in each scene. In both experiments, discrimination of old and new combinations of actors and extrinsic motions relied strongly on recollection, suggesting independent but associated representations of actors and extrinsic motions. In contrast, participants discriminated old and new combinations of actors and intrinsic motions primarily on the basis of familiarity, suggesting unitized representations of actors and intrinsic motions. (c) 2015 APA, all rights reserved).

  9. Disorder effects in strongly correlated uranium compounds

    International Nuclear Information System (INIS)

    Suellow, S.; Maple, M.B.; Tomuta, D.; Nieuwenhuys, G.J.; Menovsky, A.A.; Mydosh, J.A.; Chau, R.

    2001-01-01

    Moderate levels of crystallographic disorder can dramatically affect the ground-state properties of heavy fermion compounds. In particular, the role of disorder close to a quantum critical point has been investigated in detail. However, crystallographic disorder is equally effective in altering the properties of magnetically ordered heavy fermion compounds like URh 2 Ge 2 , where disorder-induced spin-glass behavior has been observed. In this system, moreover, the magnetic ground state can be tuned from a spin-glass to a long-range ordered antiferromagnetic one by means of an annealing treatment. The transformation of the magnetic state is accompanied by a transition in the transport properties from 'quasi-insulating' (dρ/dT 2 Ge 2 will be discussed. Of particular interest is the resistivity of as-grown URh 2 Ge 2 , which resembles the Non-Fermi-liquid system UCu 4 Pd, suggesting that a common mechanism - the crystallographic disorder - controls the transport properties of these materials

  10. Effect of manganese doping on the size effect of lead zirconate titanate thin films and the extrinsic nature of 'dead layers'.

    Science.gov (United States)

    Lou, X J; Wang, J

    2010-02-10

    We have investigated the size effect in lead zirconate titanate (PZT) thin films with a range of manganese (Mn) doping concentrations. We found that the dynamic size effect in the conventional Pt/PZT/Pt thin-film capacitors could be systematically reduced and almost completely eliminated by increasing Mn doping concentration. The interfacial layer at the electrode-film interface appears to disappear almost entirely for the PZT films with ∼ 2% Mn doping levels, confirmed by the fits using the conventional 'in-series capacitor' model. Our work indicates that the dynamic size effect in ferroelectrics is extrinsic in nature, supporting the work by Saad et al. Other implications of our results have also been discussed. By comparing a variety of experimental studies in the literature we propose a scenario that the 'dead layer' between PZT (or barium strontium titanate, BST) and metal electrodes such as Pt and Au might have a defective pyrochlore/fluorite-like structure (possibly with a small portion of ferroelectric perovskite phase). This scenario is then generalized by including the effect of the grain-boundary dead layer on the collapse of the dielectric constant in thinner films.

  11. OBSERVATION OF STRONG - STRONG AND OTHER BEAM - BEAM EFFECTS IN RHIC

    International Nuclear Information System (INIS)

    FISCHER, W.; BLASKIEWICZ, M.; BRENNAN, J.M.; CAMERON, P.; CONNOLLY, R.; MONTAG, C.; PEGGS, S.; PILAT, F.; PTITSYN, V.; TEPIKIAN, S.; TRBOJEVIC, D.; VAN ZEIJTS, J.

    2003-01-01

    RHIC is currently the only hadron collider in which strong-strong beam-beam effects can be seen. For the first time, coherent beam-beam modes were observed in a bunched beam hadron collider. Other beam-beam effects in RHIC were observed in operation and in dedicated experiments with gold ions, deuterons and protons. Observations include measurements of beam-beam induced tune shifts, lifetime and emittance growth measurements with and without beam-beam interaction, and background rates as a function of tunes. During ramps unequal radio frequencies in the two rings cause the crossing points to move longitudinally. Thus bunches experience beam-beam interactions only in intervals and the tunes are modulated. In this article we summarize the most important beam-beam observations made so far

  12. Effect of sucrose availability on wheel-running as an operant and as a reinforcing consequence on a multiple schedule: Additive effects of extrinsic and automatic reinforcement.

    Science.gov (United States)

    Belke, Terry W; Pierce, W David

    2015-07-01

    As a follow up to Belke and Pierce's (2014) study, we assessed the effects of repeated presentation and removal of sucrose solution on the behavior of rats responding on a two-component multiple schedule. Rats completed 15 wheel turns (FR 15) for either 15% or 0% sucrose solution in the manipulated component and lever pressed 10 times on average (VR 10) for an opportunity to complete 15 wheel turns (FR 15) in the other component. In contrast to our earlier study, the components advanced based on time (every 8min) rather than completed responses. Results showed that in the manipulated component wheel-running rates were higher and the latency to initiate running longer when sucrose was present (15%) compared to absent (0% or water); the number of obtained outcomes (sucrose/water), however, did not differ with the presentation and withdrawal of sucrose. For the wheel-running as reinforcement component, rates of wheel turns, overall lever-pressing rates, and obtained wheel-running reinforcements were higher, and postreinforcement pauses shorter, when sucrose was present (15%) than absent (0%) in manipulated component. Overall, our findings suggest that wheel-running rate regardless of its function (operant or reinforcement) is maintained by automatically generated consequences (automatic reinforcement) and is increased as an operant by adding experimentally arranged sucrose reinforcement (extrinsic reinforcement). This additive effect on operant wheel-running generalizes through induction or arousal to the wheel-running as reinforcement component, increasing the rate of responding for opportunities to run and the rate of wheel-running per opportunity. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. The effect of energy and source location on gamma camera intrinsic and extrinsic spatial resolution: an experimental and Monte Carlo study

    Science.gov (United States)

    Holstensson, Maria; Partridge, Mike; Buckley, Susan E.; Flux, Glenn D.

    2010-03-01

    Quantification of nuclear medicine image data is a prerequisite for personalized absorbed dose calculations and quantitative biodistribution studies. The spatial response of a detector is a governing factor affecting the accuracy of image quantification, and the aim of this work was to model this impact. To simulate spatial response, a value for the intrinsic spatial resolution (Rintrinsic) of the gamma camera is needed. Rintrinsic for 99mTc was measured over the field of view (FOV) and an experimental setup was designed to measure Rintrinsic for radioisotopes with higher photon energies. Monte Carlo (MC) simulations, using the codes SIMIND and GATE, were used to investigate the extrinsic effect of Rintrinsic as a function of energy and its variation across the FOV. A method was developed to calculate energy-dependent blurring values for input to MC simulations, by separate consideration of the Compton scatter and photoelectric effect in the crystal and statistical variation in the signal. Inclusion of energy-specific blurring values in simulations showed excellent agreement with experimental measurements. The maximum pixel count rate can change by up to 18% when imaged at two different points in the FOV, and errors in the maximum pixel count rate of up to 11% were shown if a blurring value for 99mTc was used for simulations of 131I. We demonstrate that the accuracy of MC simulations of gamma cameras can be significantly improved by accounting for the effect of energy on intrinsic spatial resolution.

  14. Strong expectations cancel locality effects: evidence from Hindi.

    Directory of Open Access Journals (Sweden)

    Samar Husain

    Full Text Available Expectation-driven facilitation (Hale, 2001; Levy, 2008 and locality-driven retrieval difficulty (Gibson, 1998, 2000; Lewis & Vasishth, 2005 are widely recognized to be two critical factors in incremental sentence processing; there is accumulating evidence that both can influence processing difficulty. However, it is unclear whether and how expectations and memory interact. We first confirm a key prediction of the expectation account: a Hindi self-paced reading study shows that when an expectation for an upcoming part of speech is dashed, building a rarer structure consumes more processing time than building a less rare structure. This is a strong validation of the expectation-based account. In a second study, we show that when expectation is strong, i.e., when a particular verb is predicted, strong facilitation effects are seen when the appearance of the verb is delayed; however, when expectation is weak, i.e., when only the part of speech "verb" is predicted but a particular verb is not predicted, the facilitation disappears and a tendency towards a locality effect is seen. The interaction seen between expectation strength and distance shows that strong expectations cancel locality effects, and that weak expectations allow locality effects to emerge.

  15. Reading: Intrinsic versus Extrinsic Motivation.

    Science.gov (United States)

    Ediger, Marlow

    Much debate centers on motivating student in reading achievement. Should students feel motivated from within (intrinsic motivation), or is it better to have extrinsic motivation whereby external stimuli are used to help learners achieve optimally in reading? This paper aims to analyze the two points of view about motivating students in reading…

  16. Validity of the relativistic phase shift model for the extrinsic spin Hall effect in dilute metal alloys.

    Science.gov (United States)

    Johansson, A; Herschbach, C; Fedorov, D V; Gradhand, M; Mertig, I

    2014-07-09

    Recently, a generalized relativistic phase shift model was proposed (Fedorovet al 2013 Phys. Rev. B 88 085116) for the description of the skew-scattering contribution to the spin Hall effect caused by impurities. Here, we inspect this model by means of a systematic comparison with the results of first-principles calculations performed for several metallic host systems with different substitutional impurities. It is found that for its proper application, the differences between impurity and host phase shifts should be used as input parameters. Generally, the model provides good qualitative agreement with ab initio results for hosts with a free-electron-like Fermi surface and a relatively weak spin-orbit coupling, but fails otherwise.

  17. Modeling the Effects of Intrinsic Motivation, Extrinsic Motivation, Amount of Reading, and Past Reading Achievement on Text Comprehension Between U.S. and Chinese Students

    Science.gov (United States)

    Wang, Judy Huei-yu; Guthrie, John T.

    2004-01-01

    This study examined the extent that motivational processes facilitate the comprehension of texts and the extent of culture's role in children's motivational processes of text comprehension. Relationships between intrinsic and extrinsic motivation, the amount of reading, past reading achievement, and text comprehension were examined by utilizing…

  18. The Effects of Strategy Training and an Extrinsic Incentive on Fourth- and Fifth-Grade Students' Performance, Confidence, and Calibration Accuracy

    Science.gov (United States)

    Gutierrez de Blume, Antonio P.

    2017-01-01

    This study investigated the influence of strategy training instruction and an extrinsic incentive on American fourth- and fifth-grade students' (N = 35) performance, confidence in performance, and calibration accuracy. Using an experimental design, children were randomized to either an experimental group (strategy training and an extrinsic…

  19. Strong Gravity Effects of Rotating Black Holes: Quasiperiodic Oscillations

    OpenAIRE

    Aliev, Alikram N.; Esmer, Göksel Daylan; Talazan, Pamir

    2012-01-01

    We explore strong gravity effects of the geodesic motion in the spacetime of rotating black holes in general relativity and braneworld gravity. We focus on the description of the motion in terms of three fundamental frequencies: The orbital frequency, the radial and vertical epicyclic frequencies. For a Kerr black hole, we perform a detailed numerical analysis of these frequencies at the innermost stable circular orbits and beyond them as well as at the characteristic stable orbits, at which ...

  20. New results on strong-interaction effects in antiprotonic hydrogen

    CERN Document Server

    Gotta, D; Augsburger, M A; Borchert, G L; Castelli, C M; Chatellard, D; El-Khoury, P; Egger, J P; Gorke, H; Hauser, P R; Indelicato, P J; Kirch, K; Lenz, S; Nelms, N; Rashid, K; Schult, O W B; Siems, T; Simons, L M

    1999-01-01

    Lyman and Balmer transitions of antiprotonic hydrogen and deuterium have been measured at the low-energy antiproton ring LEAR at CERN in order to determine the strong interaction effects. The X-rays were detected using charge-coupled devices (CCDs) and a reflection type crystal spectrometer. The results of the measurements support the meson-exchange models describing the medium and long range part of the nucleon-antinucleon interaction. (33 refs).

  1. New results on strong-interaction effects in antiprotonic hydrogen

    International Nuclear Information System (INIS)

    Anagnostopoulos, D. F.; Augsburger, M.; Borchert, G.; Castelli, C.; Chatellard, D.; El-Khoury, P.; Egger, J.-P.; Gorke, H.; Gotta, D.; Hauser, P.; Indelicato, P.; Kirch, K.; Lenz, S.; Nelms, N.; Rashid, K.; Schult, O. W. B.; Siems, Th.; Simons, L. M.

    1999-01-01

    Lyman and Balmer transitions of antiprotonic hydrogen and deuterium have been measured at the Low-Energy Antiproton Ring LEAR at CERN in order to determine the strong interaction effects. The X-rays were detected using Charge-Coupled Devices (CCDs) and a reflection type crystal spectrometer. The results of the measurements support the meson-exchange models describing the medium and long range part of the nucleon-antinucleon interaction

  2. Wide Bandgap Extrinsic Photoconductive Switches

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, James S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-07-03

    Semi-insulating Gallium Nitride, 4H and 6H Silicon Carbide are attractive materials for compact, high voltage, extrinsic, photoconductive switches due to their wide bandgap, high dark resistance, high critical electric field strength and high electron saturation velocity. These wide bandgap semiconductors are made semi-insulating by the addition of vanadium (4H and 6HSiC) and iron (2H-GaN) impurities that form deep acceptors. These deep acceptors trap electrons donated from shallow donor impurities. The electrons can be optically excited from these deep acceptor levels into the conduction band to transition the wide bandgap semiconductor materials from a semi-insulating to a conducting state. Extrinsic photoconductive switches with opposing electrodes have been constructed using vanadium compensated 6H-SiC and iron compensated 2H-GaN. These extrinsic photoconductive switches were tested at high voltage and high power to determine if they could be successfully used as the closing switch in compact medical accelerators.

  3. Using humour as an extrinsic source of emotion regulation in young and older adults.

    Science.gov (United States)

    Harm, Jonathan; Vieillard, Sandrine; Didierjean, André

    2014-10-01

    It has been suggested that intrinsic abilities for regulating emotions remain stable or improve with ageing, but, to date, no studies have examined age-related differences in extrinsic emotion regulation. Since humour has been found to be an effective form of emotion regulation, we used a paradigm similar to that of Strick and colleagues (2009) with two objectives: to compare extrinsic humorous emotion regulation in young and older adults and to test whether the potential beneficial effect of humour on negative emotion is better explained by the cognitive distraction hypothesis or by the positive affect elicitation hypothesis. To this end, neutral, moderately, and strongly negative pictures followed by humorous, simply positive, or weird cartoons, controlled for both their funniness and cognitive demands, were presented to 26 young and 25 older adults with the instruction to report their negative feelings. When induced to feel moderately negative emotions, both young and older adults reported a lower negative feeling after viewing the humorous cartoons than after the other ones. This indicates that the extrinsic humorous emotion regulation skill remains stable with ageing and suggests that the beneficial effect of humour on emotional feeling cannot be seen as a purely cognitive distraction.

  4. Superconducting proximity effect in the strong-coupling limit

    International Nuclear Information System (INIS)

    Wilvert, W.

    1975-01-01

    A generalization of the theory of the superconducting proximity effect is presented which takes into account strong-coupling in the superconductors. The results are found to agree with a model of weak-coupled superconductors with differing Debye frequencies which are in proximity. It is found that logarithmic averaging of phonon frequencies is an improvement on the original McMillan theory (1968). Comparison of the theory with data on thin films and on eutectic alloys is found to give good agreement. 19 references

  5. Strong dynamical effects during stick-slip adhesive peeling.

    Science.gov (United States)

    Dalbe, Marie-Julie; Santucci, Stéphane; Cortet, Pierre-Philippe; Vanel, Loïc

    2014-01-07

    We consider the classical problem of the stick-slip dynamics observed when peeling a roller adhesive tape at a constant velocity. From fast imaging recordings, we extract the dependence of the stick and slip phase durations on the imposed peeling velocity and peeled ribbon length. Predictions of Maugis and Barquins [in Adhesion 12, edited by K. W. Allen, Elsevier ASP, London, 1988, pp. 205-222] based on a quasistatic assumption succeed to describe quantitatively our measurements of the stick phase duration. Such a model however fails to predict the full stick-slip cycle duration, revealing strong dynamical effects during the slip phase.

  6. Effectiveness of Advanced Stay Strong, Stay Healthy in Community Settings

    Directory of Open Access Journals (Sweden)

    Emily M. Crowe MS

    2015-07-01

    Full Text Available The goal of this research was to investigate the effectiveness of the 10-week, University of Missouri (MU Extension strength training program Advanced Stay Strong, Stay Healthy (ASSSH. It was hypothesized that the program can improve strength, balance, agility, and flexibility—all physical measures of falling among seniors. Matched pair t tests were used to compare differences in five physical measures of health, body composition, and percent body fat (%BF. Two-way ANOVA was conducted to examine the age effects on changes in physical health from the start and finish of the exercise program. Following programming, participants significantly improved strength, flexibility, and balance, and significantly reduced %BF ( p < .05. Our data indicate that ASSSH can improve the physical health of senior citizens and can successfully be translated into community practice by MU Extension professionals.

  7. INTRINSIC AND EXTRINSIC MOTIVATION - AN INVESTIGATION OF PERFORMANCE CORRELATION

    Directory of Open Access Journals (Sweden)

    Abrudan Maria-Madela

    2011-07-01

    Full Text Available A series of research untaken in the last decade have revealed some interesting aspects regarding the effects of different types of motivation on performance. Among the researchers who have shown interest in this field we can number: Richard Ryan, Edward Deci, Sam Glucksberg, Dan Ariely, Robert Eisenhower, Linda Shanock, analysts from London School of Economics, and others. Their findings suggest that extrinsic incentives may have a negative impact on overall performance, but a general agreement in this respect has not been reached. In this paper we intend to shed some light upon the relationship between intrinsic and extrinsic motivation and performance. Experts define intrinsic motivation as being the execution of a task or activity because of the inherent satisfaction arising from it rather than due to some separate outcome. In contrast with intrinsic motivation, we speak of extrinsic motivation whenever an activity is done in order to attain some separable outcome. With the purpose of contributing to the clarification of the links between concepts, we initiated and conducted an explanatory research. The research is based on the analysis of the relations between the results obtained by third year students and their predominant type of motivation. For this, we formulated and tested four work hypotheses using a combination of quantitative methods (investigation and qualitative methods (focus group. After the validation of the questionnaires, the respondents were divided into four categories: intrinsically motivated, extrinsically motivated, both intrinsically and extrinsically motivated and unmotivated. To analyze the collected data, we made use of Excel and SPSS. Some of the primary conclusions of the research are as follows: as the average increases, the percent of individuals having both extrinsic and intrinsic motivation is decreasing; the highest percentage of unmotivated students is concentrated in the highest average category; Female

  8. Wide Bandgap Extrinsic Photoconductive Switches

    Science.gov (United States)

    Sullivan, James Stephen

    Wide Bandgap Extrinsic Photoconductive Switches Semi-insulating Gallium Nitride, 4H and 6H Silicon Carbide are attractive materials for compact, high voltage, extrinsic, photoconductive switches due to their wide bandgap, high dark resistance, high critical electric field strength and high electron saturation velocity. These wide bandgap semiconductors are made semi-insulating by the addition of vanadium (4H and 6H-SiC) and iron (2H-GaN) impurities that form deep acceptors. These deep acceptors trap electrons donated from shallow donor impurities. The electrons can be optically excited from these deep acceptor levels into the conduction band to transition the wide bandgap semiconductor materials from a semi-insulating to a conducting state. Extrinsic photoconductive switches with opposing electrodes have been constructed using vanadium compensated 6H-SiC and iron compensated 2H-GaN. These extrinsic photoconductive switches were tested at high voltage and high power to determine if they could be successfully used as the closing switch in compact medical accelerators. The successful development of a vanadium compensated, 6H-SiC extrinsic photoconductive switch for use as a closing switch for compact accelerator applications was realized by improvements made to the vanadium, nitrogen and boron impurity densities. The changes made to the impurity densities were based on the physical intuition outlined and simple rate equation models. The final 6H-SiC impurity 'recipe' calls for vanadium, nitrogen and boron densities of 2.5 e17 cm-3, 1.25e17 cm-3 and ≤ 1e16 cm-3, respectively. This recipe was originally developed to maximize the quantum efficiency of the vanadium compensated 6H-SiC, while maintaining a thermally stable semi-insulating material. The rate equation models indicate that, besides increasing the quantum efficiency, the impurity recipe should be expected to also increase the carrier recombination time. Three generations of 6H-SiC materials were tested. The

  9. Emotion impairs extrinsic source memory--An ERP study.

    Science.gov (United States)

    Mao, Xinrui; You, Yuqi; Li, Wen; Guo, Chunyan

    2015-09-01

    Substantial advancements in understanding emotional modulation of item memory notwithstanding, controversies remain as to how emotion influences source memory. Using an emotional extrinsic source memory paradigm combined with remember/know judgments and two key event-related potentials (ERPs)-the FN400 (a frontal potential at 300-500 ms related to familiarity) and the LPC (a later parietal potential at 500-700 ms related to recollection), our research investigated the impact of emotion on extrinsic source memory and the underlying processes. We varied a semantic prompt (either "people" or "scene") preceding a study item to manipulate the extrinsic source. Behavioral data indicated a significant effect of emotion on "remember" responses to extrinsic source details, suggesting impaired recollection-based source memory in emotional (both positive and negative) relative to neutral conditions. In parallel, differential FN400 and LPC amplitudes (correctly remembered - incorrectly remembered sources) revealed emotion-related interference, suggesting impaired familiarity and recollection memory of extrinsic sources associated with positive or negative items. These findings thus lend support to the notion of emotion-induced memory trade off: while enhancing memory of central items and intrinsic/integral source details, emotion nevertheless disrupts memory of peripheral contextual details, potentially impairing both familiarity and recollection. Importantly, that positive and negative items result in comparable memory impairment suggests that arousal (vs. affective valence) plays a critical role in modulating dynamic interactions among automatic and elaborate processes involved in memory. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Extrinsic Reinforcement in the Classroom: Bribery or Best Practice

    Science.gov (United States)

    Akin-Little, K. Angeleque; Eckert, Tanya L.; Lovett, Benjamin J.; Little, Steven G.

    2004-01-01

    The debate over the effects of the use of extrinsic reinforcement in classrooms, businesses, and societal settings has been occurring for over 30 years. Some theorists have cautioned against the use of reward, whereas others have found little, if any, detrimental effect. This article examines the debate with an emphasis on data-based findings. The…

  11. Binding of intrinsic and extrinsic features in working memory.

    Science.gov (United States)

    Ecker, Ullrich K H; Maybery, Murray; Zimmer, Hubert D

    2013-02-01

    There is ongoing debate concerning the mechanisms of feature binding in working memory. In particular, there is controversy regarding the extent to which these binding processes are automatic. The present article demonstrates that binding mechanisms differ depending on whether the to-be-integrated features are perceived as forming a coherent object. We presented a series of experiments that investigated the binding of color and shape, whereby color was either an intrinsic feature of the shape or an extrinsic feature of the shape's background. Results show that intrinsic color affected shape recognition, even when it was incidentally studied and irrelevant for the recognition task. In contrast, extrinsic color did not affect shape recognition, even when the association of color and shape was encoded and retrievable on demand. This strongly suggests that binding of intrinsic intra-item information but not extrinsic contextual information is obligatory in visual working memory. We highlight links to perception as well as implicit and explicit long-term memory, which suggest that the intrinsic-extrinsic dimension is a principle relevant to multiple domains of human cognition. 2013 APA, all rights reserved

  12. Effect of random charge fluctuation on strongly coupled dusty Plasma

    Science.gov (United States)

    Issaad, M.; Rouiguia, L.; Djebli, M.

    2008-09-01

    Modeling the interaction between particles is an open issue in dusty plasma. We dealt with strongly coupled dust particles in two dimensional confined system. For small number of clusters, we investigate the effect of random charge fluctuation on background configuration. The study is conducted for a short rang as well as a long rang potential interaction. Numerical simulation is performed using Monte-Carlo simulation in the presence of parabolic confinement and at low temperature. We have studied the background configurations for a dust particles with constant charge and in the presence of random charge fluctuation due to the discrete nature of charge carriers. The latter is studied for a positively charged dust when the dominant charging process is due to photo-emission from the dust surface. It is found, for small classical cluster consisting of small number of particles, short rang potential gives the same result as long rang one. It is also found that the random charge fluctuation affect the background configurations.

  13. Extrinsic Rewards and Intrinsic Motivation in Children. Final Report.

    Science.gov (United States)

    Lepper, Mark R.

    Three experiments were conducted to examine the effects of providing extrinsic rewards for engaging in an activity on children's subsequent intrinsic interest in that activity. In each study, preschool children were asked to engage in an activity of initial intrinsic interest in individual experimental sessions. The children agreed to engage in…

  14. Certain relativistic effects due to strong electromagnetic fields in plasmas

    International Nuclear Information System (INIS)

    Tsintsadze, N.L.

    1974-01-01

    It is shown that the propagation of a strong electromagnetic wave in an electron plasma can lead to a generation of a constant electron current along the direction of propagation and to a large increase in the average electron density. (Auth.)

  15. Effective Field Theories and Strong Interactions. Final Technical Report

    International Nuclear Information System (INIS)

    Fleming, Sean

    2011-01-01

    The framework of Effective Field Theories (EFTs) allows us to describe strong interactions in terms of degrees of freedom relevant to the energy regimes of interest, in the most general way consistent with the symmetries of QCD. Observables are expanded systematically in powers of M lo /M hi , where M lo (M hi ) denotes a low-(high-)energy scale. This organizational principle is referred to as 'power counting'. Terms of increasing powers in the expansion parameter are referred to as leading order (LO), next-to-leading order (NLO), etc. Details of the QCD dynamics not included explicitly are encoded in interaction parameters, or 'low-energy constants' (LECs), which can in principle be calculated from an explicit solution of QCD - for example via lattice simulations- but can also be determined directly from experimental data. QCD has an intrinsic scale M QCD ≅ 1 GeV, at which the QCD coupling constant α s (M QCD ) becomes large and the dynamics becomes non-perturbative. As a consequence M QCD sets the scale for the masses of most hadrons, such as the nucleon mass m N ≅ 940 MeV. EFTs can roughly be divided into two categories: those that can be matched onto QCD in perturbation theory, which we call high-energy EFTs, and those that cannot be matched perturbatively, which we call low-energy EFTs. In high-energy EFTs, M QCD typically sets the low-energy scale, and all the dynamics associated with this scale reside in matrix elements of EFT operators. These non-perturbative matrix elements are the LECs and are also referred to as long-distance contributions. Each matrix element is multiplied by a short-distance coefficient, which contains the dynamics from the high scale M hi . Since M hi >> M QCD , α s (M hi ) hi ∼ M Q , the heavy-quark mass, and in addition to M QCD there are low scales associated with the typical relative momentum ∼ M Q v and energy ∼ M Q v 2 of the heavy quarks. Depending on the sizes of M Q and the heavy-quark velocity v these scales can

  16. How strong and generalisable is the Generation Y effect?

    DEFF Research Database (Denmark)

    Mueller, Simone; Remaud, Hervé; Chabin, Yann

    2011-01-01

    alcoholic beverage consumption. A number of noticeable differences appeared between countries: wine involvement and consumption increases with age in traditional European wine markets, while they decrease in North America; environmental concerns and purchase channel usage hardly differ between generations......Purpose – This study aims to investigate how strongly Generation Y consumers differ in their values, attitudes and wine and alcoholic beverage consumption behaviour from older generations. The comparison spans seven culturally different markets. Design/methodology/approach – Large representative...

  17. Motor memory is encoded as a gain-field combination of intrinsic and extrinsic action representations.

    Science.gov (United States)

    Brayanov, Jordan B; Press, Daniel Z; Smith, Maurice A

    2012-10-24

    Actions can be planned in either an intrinsic (body-based) reference frame or an extrinsic (world-based) frame, and understanding how the internal representations associated with these frames contribute to the learning of motor actions is a key issue in motor control. We studied the internal representation of this learning in human subjects by analyzing generalization patterns across an array of different movement directions and workspaces after training a visuomotor rotation in a single movement direction in one workspace. This provided a dense sampling of the generalization function across intrinsic and extrinsic reference frames, which allowed us to dissociate intrinsic and extrinsic representations and determine the manner in which they contributed to the motor memory for a trained action. A first experiment showed that the generalization pattern reflected a memory that was intermediate between intrinsic and extrinsic representations. A second experiment showed that this intermediate representation could not arise from separate intrinsic and extrinsic learning. Instead, we find that the representation of learning is based on a gain-field combination of local representations in intrinsic and extrinsic coordinates. This gain-field representation generalizes between actions by effectively computing similarity based on the (Mahalanobis) distance across intrinsic and extrinsic coordinates and is in line with neural recordings showing mixed intrinsic-extrinsic representations in motor and parietal cortices.

  18. Spin effects in strong-field laser-electron interactions

    International Nuclear Information System (INIS)

    Ahrens, S; Bauke, H; Müller, T-O; Villalba-Chávez, S; Müller, C

    2013-01-01

    The electron spin degree of freedom can play a significant role in relativistic scattering processes involving intense laser fields. In this contribution we discuss the influence of the electron spin on (i) Kapitza-Dirac scattering in an x-ray laser field of high intensity, (ii) photo-induced electron-positron pair production in a strong laser wave and (iii) multiphoton electron-positron pair production on an atomic nucleus. We show that in all cases under consideration the electron spin can have a characteristic impact on the process properties and their total probabilities. To this end, spin-resolved calculations based on the Dirac equation in the presence of an intense laser field are performed. The predictions from Dirac theory are also compared with the corresponding results from the Klein-Gordon equation.

  19. Fitness, Extrinsic Complexity and Informing Science

    Directory of Open Access Journals (Sweden)

    Grandon Gill

    2017-03-01

    We raise concerns about society’s continuing investment in academic research that discounts the extrinsic complexity of the domains under study. Future Research We highlight a need for research to operationalize the concepts of fitness and complexity in practice.

  20. Adaptive influence of extrinsic and intrinsic factors on variation of incubation periods among tropical and temperate passerines

    Science.gov (United States)

    Martin, Thomas E.; Ton, Riccardo; Oteyza, Juan C.

    2018-01-01

    Understanding intrinsic (physiological) and extrinsic (e.g., temperature) causes of variation in embryonic development time (incubation period) is important because they can have different impacts on individual quality. Robert Ricklefs and colleagues have argued that longer incubation periods result primarily from intrinsic physiological programs that increase individual quality and adult survival. They claim that incubation periods are largely invariant and that extrinsic factors like temperature have little impact. We have argued that adult survival may be a cause rather than a consequence of much of the variation in embryonic development time. A reduction in extrinsic sources of annual adult mortality (e.g., migration, predation, nonbreeding-season mortality) favors reduced parental effort during incubation to minimize costs to future reproduction and survival. Reduced parental effort, in turn, manifests as cooler average egg temperatures that yield longer incubation periods. Ricklefs and colleagues mischaracterized our hypothesis and deconstructed their own incorrect version, while also making some incorrect statements. We show that reevaluation of previous evidence provided by this group actually supports a role of egg temperature for the variation in incubation periods. We also summarize other observational and experimental evidence that incubation periods are not invariant and that egg temperature has a strong causal influence on variation within and among species. In fact, egg temperature explains ∼60% of the difference in incubation periods among species. The remaining ∼40% reflects intrinsic physiological programs and other factors, potentially providing intrinsic benefits. Ultimately, annual adult mortality explains substantial variation in parental effort and egg temperature, and the latter strongly explains variation in incubation periods. Both intrinsic programs and extrinsic temperature effects need to be considered in attempts to understand

  1. Radiation effects on relativistic electrons in strong external fields

    International Nuclear Information System (INIS)

    Iqbal, Khalid

    2013-01-01

    The effects of radiation of high energy electron beams are a major issue in almost all types of charged particle accelerators. The objective of this thesis is both the analytical and numerical study of radiation effects. Due to its many applications the study of the self force has become a very active and productive field of research. The main part of this thesis is devoted to the study of radiation effects in laser-based plasma accelerators. Analytical models predict the existence of radiation effects. The investigation of radiation reaction show that in laser-based plasma accelerators, the self force effects lower the energy gain and emittance for moderate energies electron beams and increase the relative energy spread. However, for relatively high energy electron beams, the self radiation and retardation (radiation effects of one electron on the other electron of the system) effects increase the transverse emittance of the beam. The energy gain decreases to even lower value and relative energy spread increases to even higher value due to high radiation losses. The second part of this thesis investigates with radiation reaction in focused laser beams. Radiation effects are very weak even for high energy electrons. The radiation-free acceleration and the simple practical setup make direct acceleration in a focused laser beam very attractive. The results presented in this thesis can be helpful for the optimization of future electron acceleration experiments, in particular in the case of laser-plasma accelerators.

  2. Effective magnetic moment of neutrinos in strong magnetic fields

    CERN Document Server

    Pérez, A; Masood, S S; Gaitan, R; Rodríguez, S

    2002-01-01

    In this paper we compute the effective magnetic moment of neutrinos propagating in dense high magnetized medium. Taking typical values of magnetic field and densities of astrophysical objects (such as the cores of supernovae and neutron stars) we obtain an effective type of dipole magnetic moment in agreement with astrophysical and cosmological bounds. (Author)

  3. The Connect Effect Building Strong Personal, Professional, and Virtual Networks

    CERN Document Server

    Dulworth, Michael

    2008-01-01

    Entrepreneur and executive development expert Mike Dulworth's THE CONNECT EFFECT provides readers with a simple framework and practical tools for developing that crucial competitive advantage: a high-quality personal, professional/organizational and virtual network.

  4. Effective bounds on strong unicity in L1-approximation

    DEFF Research Database (Denmark)

    Kohlenbach, Ulrich; Oliva, Paulo B.

    In this paper we present another case study in the general project of Proof Mining which means the logical analysis of prima facie non-effective proofs with the aim of extracting new computationally relevant data. We use techniques based on monotone functional interpretation (developed in [17]) t...

  5. Strong delayed interactive effects of metal exposure and warming

    DEFF Research Database (Denmark)

    Debecker, Sara; Dinh, Khuong Van; Stoks, Robby

    2017-01-01

    As contaminants are often more toxic at higher temperatures, predicting their impact under global warming remains a key challenge for ecological risk assessment. Ignoring delayed effects, synergistic interactions between contaminants and warming, and differences in sensitivity across species......’ ranges could lead to an important underestimation of the risks. We addressed all three mechanisms by studying effects of larval exposure to zinc and warming before, during, and after metamorphosis in Ischnura elegans damselflies from high- and lowlatitude populations. By integrating these mechanisms...... was especially remarkable in high-latitude animals, as they appeared almost insensitive to zinc during the larval stage. Second, the well-known synergism between metals and warming was manifested not only during the larval stage but also after metamorphosis, yet notably only in low-latitude damselflies...

  6. Are competition and extrinsic motivation reliable predictors of academic cheating?

    Science.gov (United States)

    Orosz, Gábor; Farkas, Dávid; Roland-Lévy, Christine

    2013-01-01

    Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356). Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes toward self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior.

  7. Are competition and extrinsic motivation reliable predictors of academic cheating?

    Directory of Open Access Journals (Sweden)

    Gábor eOrosz

    2013-02-01

    Full Text Available Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356. Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes towards self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior.

  8. Are Competition and Extrinsic Motivation Reliable Predictors of Academic Cheating?

    Science.gov (United States)

    Orosz, Gábor; Farkas, Dávid; Roland-Lévy, Christine

    2013-01-01

    Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356). Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes toward self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior. PMID:23450676

  9. Intrinsic and extrinsic motivation among adolescent ten-pin bowlers in kuala lumpur, malaysia.

    Science.gov (United States)

    Teo, Eng-Wah; Khoo, Selina; Wong, Rebecca; Wee, Eng-Hoe; Lim, Boon-Hooi; Rengasamy, Shabesan Sit

    2015-03-29

    Motivation has long been associated with sports engagement. However, to date no research has been performed to understand the domain of motivation among ten-pin bowlers. The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic) based on self-determination theory from the perspective of gender and the bowler type (competitive vs. casual). A total of 240 bowlers (104 male, 136 female; 152 competitive, 88 casual) with a mean age of 16.61 ± 0.78 years were recruited in Kuala Lumpur. The Sport Motivation Scale, a 28-item self-report questionnaire measuring seven subscales (i.e., intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, extrinsic motivation to identify regulation, extrinsic motivation for introjection regulation, extrinsic motivation to external regulation, and amotivation) was administered. Results showed significant differences (t=10.43, df=239, p=0.01) between total scores of intrinsic and extrinsic motivation among ten-pin bowlers. There were significant gender differences with respect to intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, and extrinsic motivation to identify regulation. However, no significant bowler type differences were found for either the intrinsic (t=-1.15, df=238, p=0.25) or extrinsic (t=-0.51, df=238, p=0.61) motivation dimensions. In conclusion, our study demonstrated substantial intrinsic motivation for gender effects, but no bowler type effects among adolescent ten-pin bowlers.

  10. Intrinsic and Extrinsic Motivation Among Adolescent Ten-Pin Bowlers in Kuala Lumpur, Malaysia

    Directory of Open Access Journals (Sweden)

    Teo Eng-Wah

    2015-03-01

    Full Text Available Motivation has long been associated with sports engagement. However, to date no research has been performed to understand the domain of motivation among ten-pin bowlers. The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic based on self-determination theory from the perspective of gender and the bowler type (competitive vs. casual. A total of 240 bowlers (104 male, 136 female; 152 competitive, 88 casual with a mean age of 16.61 ± 0.78 years were recruited in Kuala Lumpur. The Sport Motivation Scale, a 28-item self-report questionnaire measuring seven subscales (i.e., intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, extrinsic motivation to identify regulation, extrinsic motivation for introjection regulation, extrinsic motivation to external regulation, and amotivation was administered. Results showed significant differences (t=10.43, df=239, p=0.01 between total scores of intrinsic and extrinsic motivation among tenpin bowlers. There were significant gender differences with respect to intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, and extrinsic motivation to identify regulation. However, no significant bowler type differences were found for either the intrinsic (t=-1.15, df=238, p=0.25 or extrinsic (t=-0.51, df=238, p=0.61 motivation dimensions. In conclusion, our study demonstrated substantial intrinsic motivation for gender effects, but no bowler type effects among adolescent ten-pin bowlers.

  11. Effect of strong fragrance on olfactory detection threshold.

    Science.gov (United States)

    Fasunla, Ayotunde James; Douglas, David Dayo; Adeosun, Aderemi Adeleke; Steinbach, Silke; Nwaorgu, Onyekwere George Benjamin

    2014-09-01

    To assess the olfactory threshold of healthy volunteers at the University College Hospital, Ibadan and to investigate the effect of perfume on their olfactory detection thresholds. A quasi-experimental study on olfactory detection thresholds of healthy volunteers from September 2013 to November 2013. Tertiary health institution. A structured questionniare was administered to the participants in order to obtain information on sociodemographics, occupation, ability to perceive smell, use of perfume, effects of perfume on appetite and self-confidence, history of allergy, and previous nasal surgery. Participants subjectively rated their olfactory performance. Subsequently, they had olfactory detection threshold testing done at baseline and after exposure to perfume with varied concentrations of n-butanol in a forced triple response and staircase fashion. Healthy volunteers, 37 males and 63 females, were evaluated. Their ages ranged from 19 to 59 years with a mean of 31 years ± 8. Subjectively, 94% of the participants had excellent olfactory function. In the pre-exposure forced triple response, 88% were able to detect the odor at ≤.25 mmol/l concentration while in the post-exposure forced triple response, only 66% were able to detect the odor at ≤.25 mmol/l concentration. There is also a statistical significant difference in the olfactory detection threshold score between the pre-exposure and post-exposure period in the participants (P fragrances affects the olfactory detection threshold. Therefore patients and clinicians should be aware of this and its effects on the outcome of test of olfaction. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

  12. Stirling engines using working fluids with strong real gas effects

    International Nuclear Information System (INIS)

    Invernizzi, Costante M.

    2010-01-01

    Real gas effects typical of the critical region of working fluids are a powerful tool to increase the energy performances of Stirling cycles, mainly at low top temperatures. To carry out the compression near the critical region the working fluids must have a critical temperature near environmental conditions and the use of organic working substances (pure or in suitable mixtures) as a matter of fact begins compulsory. The moderate thermal stability of the organic working fluids limits the maximum temperatures to 300-400 deg. C and as a consequence, the achievable cycles efficiencies result rather low. Carbon dioxide, with a critical temperature of 31 deg. C, is, among the traditionally inorganic gases, an exception and is considered here in comparison with organic substances. But the good thermodynamics of the cycles allows, in the considered cases, conversion efficiencies of about 20%, with good specific powers. The good energy performance of real gas Stirling cycles is obtained at the cost of high maximum cycle pressure, in the range of at least 100-300 bar. These high pressures nevertheless have large positive effects on the heat power transferred per unit of pumping mechanical power, and the low top temperatures have a positive influence on the material problems for the hottest engine parts.

  13. Strong surface effect on direct bulk flexoelectric response in solids

    International Nuclear Information System (INIS)

    Yurkov, A. S.; Tagantsev, A. K.

    2016-01-01

    In the framework of a continuum theory, it is shown that the direct bulk flexoelectric response of a finite sample essentially depends on the surface polarization energy, even in the thermodynamic limit where the body size tends to infinity. It is found that a modification of the surface energy can lead to a change in the polarization response by a factor of two. The origin of the effect is an electric field produced by surface dipoles induced by the strain gradient. The unexpected sensitivity of the polarization response to the surface energy in the thermodynamic limit is conditioned by the fact that the moments of the surface dipoles may scale as the body size

  14. Plasma opening switch with extrinsic magnetic field

    CERN Document Server

    Dolgachev, G; Maslennikov, D

    2001-01-01

    Summary form only given, as follows. We have demonstrated in series of experiments that plasma opening switch (POS) switching voltage (UPOS) is defined by energy density (w) deposited in the POS plasma. If we then consider a plasma erosion mainly responsible for the effect of POS switching (the erosion effect could be described by Hall or Child-Langmuir models) the energy density (w) could be measured as a function of a system "macro-parameter" such as the initial charging voltage of the capacity storage system (the Marx pulsed voltage generator) UMarx. The POS voltage in this case could be given by UPOS"aw=aUMarx4/7, where a is a constant. This report demonstrates that for the high-impedance POS which has limited charge density transferred through the POS plasma a"2.5 (MV3/7) with no external magnetic field applied. The use of the extrinsic magnetic field allows to increase a up to 3.6 (MV3/7) and to achieve higher voltages at the opening phase - UPOS=3.6UMarx4/7. To verify this approach set of experimental ...

  15. Consolidation power of extrinsic rewards: reward cues enhance long-term memory for irrelevant past events.

    Science.gov (United States)

    Murayama, Kou; Kitagami, Shinji

    2014-02-01

    Recent research suggests that extrinsic rewards promote memory consolidation through dopaminergic modulation processes. However, no conclusive behavioral evidence exists given that the influence of extrinsic reward on attention and motivation during encoding and consolidation processes are inherently confounded. The present study provides behavioral evidence that extrinsic rewards (i.e., monetary incentives) enhance human memory consolidation independently of attention and motivation. Participants saw neutral pictures, followed by a reward or control cue in an unrelated context. Our results (and a direct replication study) demonstrated that the reward cue predicted a retrograde enhancement of memory for the preceding neutral pictures. This retrograde effect was observed only after a delay, not immediately upon testing. An additional experiment showed that emotional arousal or unconscious resource mobilization cannot explain the retrograde enhancement effect. These results provide support for the notion that the dopaminergic memory consolidation effect can result from extrinsic reward.

  16. Let's stay together? Intrinsic and extrinsic factors involved in pair bond dissolution in a recolonizing wolf population.

    Science.gov (United States)

    Milleret, Cyril; Wabakken, Petter; Liberg, Olof; Åkesson, Mikael; Flagstad, Øystein; Andreassen, Harry Peter; Sand, Håkan

    2017-01-01

    For socially monogamous species, breeder bond dissolution has important consequences for population dynamics, but the extent to which extrinsic or intrinsic population factors causes pair dissolution remain poorly understood, especially among carnivores. Using an extensive life-history data set, a survival analysis and competing risks framework, we examined the fate of 153 different wolf (Canis lupus) pairs in the recolonizing Scandinavian wolf population, during 14 winters of snow tracking and DNA monitoring. Wolf pair dissolution was generally linked to a mortality event and was strongly affected by extrinsic (i.e. anthropogenic) causes. No divorce was observed, and among the pair dissolution where causes have been identified, death of one or both wolves was always involved. Median time from pair formation to pair dissolution was three consecutive winters (i.e. approximately 2 years). Pair dissolution was mostly human-related, primarily caused by legal control actions (36·7%), verified poaching (9·2%) and traffic-related causes (2·1%). Intrinsic factors, such as disease and age, accounted for only 7·7% of pair dissolutions. The remaining 44·3% of dissolution events were from unknown causes, but we argue that a large portion could be explained by an additional source of human-caused mortality, cryptic poaching. Extrinsic population factors, such as variables describing the geographical location of the pair, had a stronger effect on risk of pair dissolution compared to anthropogenic landscape characteristics. Population intrinsic factors, such as the inbreeding coefficient of the male pair member, had a negative effect on pair bond duration. The mechanism behind this result remains unknown, but might be explained by lower survival of inbred males or more complex inbreeding effects mediated by behaviour. Our study provides quantitative estimates of breeder bond duration in a social carnivore and highlights the effect of extrinsic (i.e. anthropogenic) and

  17. Ageing in Escherichia coli requires damage by an extrinsic agent.

    Science.gov (United States)

    Rang, Camilla U; Peng, Annie Y; Poon, Art F; Chao, Lin

    2012-06-01

    Evidence for ageing in symmetrically dividing bacteria such as Escherichia coli has historically been conflicting. Early work found weak or no evidence. More recent studies found convincing evidence, but negative results are still encountered. Because bacterial ageing is believed to result from non-genetic (e.g. oxidative) damage, we tested the possibility that the negative outcomes resulted from the lack of an extrinsic damage agent. We found that streptomycin, which produces mistranslated proteins that are more vulnerable to oxidation, was able to induce both damage and ageing in bacterial populations. A dosage effect relating the level of damage to the concentration of streptomycin was observed. Our results explain the previous inconsistencies, because all studies that failed to find evidence for bacterial ageing did not use a damage agent. However, all studies that succeeded in finding evidence utilized fluorescent proteins as a visual marker. We suggest that ageing in those studies was induced by the harmful effects of an extrinsic factor, such as the proteins themselves or the excitation light. Thus, all of the earlier studies can be reconciled and bacterial ageing is a real phenomenon. However, the study and observation of bacterial ageing require the addition of an extrinsic damage agent.

  18. Intrinsic and extrinsic electrical and thermal transport of bulk black phosphorus

    Science.gov (United States)

    Hu, Sile; Xiang, Junsen; Lv, Meng; Zhang, Jiahao; Zhao, Hengcan; Li, Chunhong; Chen, Genfu; Wang, Wenhong; Sun, Peijie

    2018-01-01

    We report a comprehensive investigation of the electrical, thermal, and thermoelectric transport properties of bulk single-crystalline black phosphorus in wide temperature (2-300 K) and field (0-9 T) ranges. Electrical transport below T ≈ 250 K is found to be dominated by extrinsic hole-type charge carriers with large mobility exceeding 104 cm2/V s at low temperatures. While thermal transport measurements reveal an enhanced in-plane thermal conductivity maximum κ = 180 W/m K at T ≈ 25 K, it appears still to be largely constrained by extrinsic phonon scattering processes, e.g., the electron-phonon process, in addition to intrinsic umklapp scattering. The thermoelectric power and Nernst effect seem to be strongly influenced by ambipolar transport of charge carriers with opposite signs in at least the high-temperature region above 200 K, which diminishes the thermoelectric power factor of this material. Our results provide a timely update to the transport properties of bulk black phosphorus for future fundamental and applied research.

  19. Recovery of colonic transit following extrinsic nerve damage in rats.

    Science.gov (United States)

    Ridolfi, Timothy J; Tong, Wei Dong; Kosinski, Lauren; Takahashi, Toku; Ludwig, Kirk A

    2011-06-01

    Injury to pelvic sympathetic and parasympathetic nerves from surgical and obstetrical trauma has long been cited as a cause for abnormal colorectal motility in humans. Using a rat model, acute transaction of these extrinsic nerves has been shown to effect colorectal motility. The aim of this study is to determine in a rat model how transection of these extrinsic nerves affects colonic transit over time. Eighty-two Sprague-Dawley rats underwent placement of a tunneled catheter into the proximal colon. Bilateral hypogastric, pelvic nerves (HGN and PN) or both were transected in 66 rats. The remaining 16 rats received a sham operation. Colonic transit was evaluated at postoperative days (PODs) 1, 3, and 7 by injecting and calculating the geometric center (GC) of the distribution of (51)Cr after 3 h of propagation. At POD 1, transection of PNs significantly delayed colonic transit (GC = 4.9, p < 0.05), while transection of HGNs (GC = 8.5, p < 0.05) or transection of both nerves (GC = 7.8, p < 0.05) significantly accelerated colonic transit, when compared with sham operation (GC = 6.0). A significant trend toward recovery was noted in both the HGN and PN transection groups at POD 7. Damage to the extrinsic sympathetic and/or parasympathetic PNs affects colonic transit acutely. These changes in large bowel motor function normalize over time implicating a compensatory mechanism within the bowel itself.

  20. INTRINSIC AND EXTRINSIC MOTIVATION IN THE SELECTION ...

    African Journals Online (AJOL)

    A psychological perspective is considered that applies intrinsic and extrinsic motivational concepts to communication phenomena. The paper also tries to develop an analytical understanding of human communication-related behavior with respect to the two types of motives. Proposals are also put forward to communication ...

  1. Intrinsic and Extrinsic Motivation among Collegiate Instrumentalists

    Science.gov (United States)

    Diaz, Frank M.

    2010-01-01

    The purpose of this study was to gather and compare information on measures of intrinsic and extrinsic motivation among instrumentalists enrolled in collegiate ensembles. A survey instrument was developed to gather information concerning demographic data and responses to questions on motivational preference. Participants were undergraduate and…

  2. MODELLING OF EXTRINSIC FIBER OPTIC SAGNAC ...

    African Journals Online (AJOL)

    ABSTRACT. Ultrasonic waves are used extensively in nondestructive testing both for characterization of material properties, in this paper, we describe a fiber optic sensor suitable for detection of ultrasonic waves. This sensor is based on an extrinsic fiber optic sagnac interferometer. The proposed sensor model can act as a ...

  3. the relationship between primary school teachers extrinsic ...

    African Journals Online (AJOL)

    PROF EKWUEME

    find teachers and pupils under tree shades and in uncompleted or open roof buildings during lesson. This situation may lead to teachers' poor output as well as poor academic performance of pupils. PURPOSE OF THE STUDY: The main purpose of this study is to investigate primary school teachers' extrinsic motivation and.

  4. Intrinsic and extrinsic factors influencing large African herbivore movements

    NARCIS (Netherlands)

    Venter, J.A.; Prins, H.H.T.; Mashanova, A.; Boer, de W.F.; Slotow, R.

    2015-01-01

    Understanding environmental as well as anthropogenic factors that influence large herbivore ecological patterns and processes should underpin their conservation and management. We assessed the influence of intrinsic, extrinsic environmental and extrinsic anthropogenic factors on movement behaviour

  5. Intrinsic to extrinsic phonon lifetime transition in a GaAs-AlAs superlattice.

    Science.gov (United States)

    Hofmann, F; Garg, J; Maznev, A A; Jandl, A; Bulsara, M; Fitzgerald, E A; Chen, G; Nelson, K A

    2013-07-24

    We have measured the lifetimes of two zone-center longitudinal acoustic phonon modes, at 320 and 640 GHz, in a 14 nm GaAs/2 nm AlAs superlattice structure. By comparing measurements at 296 and 79 K we separate the intrinsic contribution to phonon lifetime determined by phonon-phonon scattering from the extrinsic contribution due to defects and interface roughness. At 296 K, the 320 GHz phonon lifetime has approximately equal contributions from intrinsic and extrinsic scattering, whilst at 640 GHz it is dominated by extrinsic effects. These measurements are compared with intrinsic and extrinsic scattering rates in the superlattice obtained from first-principles lattice dynamics calculations. The calculated room-temperature intrinsic lifetime of longitudinal phonons at 320 GHz is in agreement with the experimentally measured value of 0.9 ns. The model correctly predicts the transition from predominantly intrinsic to predominantly extrinsic scattering; however the predicted transition occurs at higher frequencies. Our analysis indicates that the 'interfacial atomic disorder' model is not entirely adequate and that the observed frequency dependence of the extrinsic scattering rate is likely to be determined by a finite correlation length of interface roughness.

  6. VOL 6. NO. 1 2015 EXTRINSIC FACTORS THAT AFFECT ...

    African Journals Online (AJOL)

    Frederick Iraki

    Keywords: Job satisfaction, clergy, extrinsic motivation, extrinsic factors. INTRODUCTION. Job satisfaction is ... depict that extrinsic motivation is the motivation to do something to make sure that some external goal is ..... According to Cooper, (2006), reductions in job security leads to lower levels of commitment and therefore ...

  7. Extrinsic doping in silicon revisited

    KAUST Repository

    Schwingenschlögl, Udo

    2010-06-17

    Both n-type and p-type doping of silicon is at odds with the charge transfer predicted by Pauling electronegativities and can only be reconciled if we no longer regarding dopant species as isolated atoms but rather consider them as clusters consisting of the dopant and its four nearest neighbor silicon atoms. The process that gives rise to n-type and p-type effects is the charge redistribution that occurs between the dopant and its neighbors, as we illustrate here using electronic structure calculations. This view point is able to explain why conventional substitutional n-type doping of carbon has been so difficult.

  8. Effect of strong electrolytes on edible oils part III: viscosity of canola ...

    African Journals Online (AJOL)

    Effect of strong electrolytes on the viscosity of canola oil in 1,4 dioxane was undertaken. The viscosity of oil in 1,4 dioxane was found to increase with the concentration of oil and decrease with rise in temperature. Strong electrolytes reduce the rate of flow of oil in 1,4 dioxane. It was noted that amongst these electrolytes, ...

  9. Anomalous Josephson effect in semiconductor nanowire with strong spin-orbit interaction and Zeeman effect

    Science.gov (United States)

    Yokoyama, Tomohiro; Eto, Mikio; Nazarov, Yuli

    2014-03-01

    We theoretically investigate the Josephson junction using quasi-one dimensional semiconductor nanowires with strong spin-orbit (SO) interaction, e.g., InSb. First, we examine a simple model using a single scatterer to describe the elastic scattering due to impurities and SO interaction in the normal region.[1] The Zeeman effect is taken into account by the spin-dependent phase shift of electron and hole through the system. The interplay between SO interaction and Zeeman effect results in a finite supercurrent even when the phase difference between two superconductors is zero. Moreover, the critical current depends on its current direction if more than one conduction channel is present in the nanowire. Next, we perform a numerical simulation by the tight-binding model for the nanowire to confirm our simple model. Then, we show that a spin-dependent Fermi velocity due to the SO interaction causes the anomalous Josephson effect.

  10. Effects of Gold Substrates on the Intrinsic and Extrinsic Activity of High-Loading Nickel-Based Oxyhydroxide Oxygen Evolution Catalysts

    DEFF Research Database (Denmark)

    Chakthranont, Pongkarn; Kibsgaard, Jakob; Gallo, Alessandro

    2017-01-01

    We systematically investigate the effects of Au substrates on the oxygen evolution activities of cathodically electrodeposited nickel oxyhydroxide (NiOOH), nickel–iron oxyhydroxide (NiFeOOH), and nickel–cerium oxyhydroxide (NiCeOOH) at varying loadings from 0 to 2000 nmol of metal/cm2. We determine...

  11. The influence of extrinsic motivation on competition-based selection.

    Science.gov (United States)

    Sänger, Jessica; Wascher, Edmund

    2011-10-10

    The biased competition approach to visuo-spatial attention proposes that the selection of competing information is effected by the saliency of the stimulus as well as by an intention-based bias of attention towards behavioural goals. Wascher and Beste (2010) [32] showed that the detection of relevant information depends on its relative saliency compared to irrelevant conflicting stimuli. Furthermore the N1pc, N2pc and N2 of the EEG varied with the strength of the conflict. However, this system could also be modulated by rather global mechanisms like attentional effort. The present study investigates such modulations by testing the influence of extrinsic motivation on the selection of competing stimuli. Participants had to detect a luminance change in various conditions among others against an irrelevant orientation change. Half of the participants were motivated to maximize their performance by the announcement of a monetary reward for correct responses. Participants who were motivated had lower error rates than participants who were not motivated. The event-related lateralizations of the EEG showed no motivation-related effect on the N1pc, which reflects the initial saliency driven orientation of attention towards the more salient stimulus. The subsequent N2pc was enhanced in the motivation condition. Extrinsic motivation was also accompanied by enhanced fronto-central negativities. Thus, the data provide evidence that the improvement of selection performance when participants were extrinsically motivated by announcing a reward was not due to changes in the initial saliency based processing of information but was foremost mediated by improved higher-level mechanisms. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Strong Effect of Azodye Layer Thickness on RM-Stabilized Photoalignment

    Science.gov (United States)

    2017-05-21

    Strong Effect of Azodye Layer Thickness on RM-Stabilized Photoalignment Colin McGinty*, Valerie Finnemeyer**, Robert Reich**, Harry Clark...vertical alignment on these substrates. For the thinner BY layers, we do not see this strong evidence of out of plane reorientation. The out of...In this report we show the surprising effect that thin azodye layers demonstrate improved stability over those that are thicker. Figure 6

  13. Long-term memory and response generalization in mushroom body extrinsic neurons in the honeybee Apis mellifera.

    Science.gov (United States)

    Haehnel, Melanie; Menzel, Randolf

    2012-02-01

    Honeybees learn to associate an odor with sucrose reward under conditions that allow the monitoring of neural activity by imaging Ca(2+) transients in morphologically identified neurons. Here we report such recordings from mushroom body extrinsic neurons - which belong to a recurrent tract connecting the output of the mushroom body with its input, potentially providing inhibitory feedback - and other extrinsic neurons. The neurons' responses to the learned odor and two novel control odors were measured 24 h after learning. We found that calcium responses to the learned odor and an odor that was strongly generalized with it were enhanced compared with responses to a weakly generalized control. Thus, the physiological responses measured in these extrinsic neurons accurately reflect what is observed in behavior. We conclude that the recorded recurrent neurons feed information back to the mushroom body about the features of learned odor stimuli. Other extrinsic neurons may signal information about learned odors to different brain regions.

  14. Intrinsic motivation and extrinsic incentives jointly predict performance: a 40-year meta-analysis.

    Science.gov (United States)

    Cerasoli, Christopher P; Nicklin, Jessica M; Ford, Michael T

    2014-07-01

    More than 4 decades of research and 9 meta-analyses have focused on the undermining effect: namely, the debate over whether the provision of extrinsic incentives erodes intrinsic motivation. This review and meta-analysis builds on such previous reviews by focusing on the interrelationship among intrinsic motivation, extrinsic incentives, and performance, with reference to 2 moderators: performance type (quality vs. quantity) and incentive contingency (directly performance-salient vs. indirectly performance-salient), which have not been systematically reviewed to date. Based on random-effects meta-analytic methods, findings from school, work, and physical domains (k = 183, N = 212,468) indicate that intrinsic motivation is a medium to strong predictor of performance (ρ = .21-45). The importance of intrinsic motivation to performance remained in place whether incentives were presented. In addition, incentive salience influenced the predictive validity of intrinsic motivation for performance: In a "crowding out" fashion, intrinsic motivation was less important to performance when incentives were directly tied to performance and was more important when incentives were indirectly tied to performance. Considered simultaneously through meta-analytic regression, intrinsic motivation predicted more unique variance in quality of performance, whereas incentives were a better predictor of quantity of performance. With respect to performance, incentives and intrinsic motivation are not necessarily antagonistic and are best considered simultaneously. Future research should consider using nonperformance criteria (e.g., well-being, job satisfaction) as well as applying the percent-of-maximum-possible (POMP) method in meta-analyses. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  15. Nontrivial effects of high-frequency excitation for strongly damped mechanical systems

    DEFF Research Database (Denmark)

    Fidlin, Alexander; Thomsen, Jon Juel

    Some nontrivial effects are investigated, which can occur if strongly damped mechanical systems are subjected to strong high-frequency (HF) excitation. The main result is a theoretical prediction, supported by numerical simulation, that for such systems the (quasi-)equilibrium states can change...... that can be substantial (depending on the strength of the HF excitation) for finite values of the damping. The analysis is focused on the differences between the classic results for weakly damped systems, and new effects for which the strong damping terms are responsible. The analysis is based...... on a slightly modified averaging technique, and includes an elementary example of an elliptically excited pendulum for illustration, alongside with a generalization to a broader class of strongly damped dynamical systems with HF excitation. As an application example, the nontrivial behavior of a classical...

  16. Nontrivial effects of high-frequency excitation for strongly damped mechanical systems

    DEFF Research Database (Denmark)

    Fidlin, Alexander; Thomsen, Jon Juel

    2008-01-01

    Some non-trivial effects are investigated, which can occur if strongly damped mechanical systems are subjected to strong high-frequency (HF) excitation. The main result is a theoretical prediction, supported by numerical simulation, that for such systems the (quasi-)equilibrium states can change...... that can be substantial depending on the strength of the HF excitation) for finite values of the damping. The analysis is focused on the differences between the classic results for weakly damped systems, and new effects for which the strong damping terms are responsible. The analysis is based on a slightly...... modified averaging technique, and includes an elementary example of an elliptically excited pendulum for illustration, alongside with a generalization to a broader class of strongly damped dynamical systems with HF excitation. As an application example, the nontrivial behavior of a classical optimally...

  17. <strong>Effectiveness of Orthoses and Foot Training in patients with Patellofemoral Pain and hyperpronationstrong>

    DEFF Research Database (Denmark)

    Mølgaard, Carsten; Kaalund, Søren; Christensen, Marianne

    of treatment with functional foot orthoses, exercises, or orthoses with exercises. The intrinsic pedal muscles play an important role in support of the medial longitudinal arch. (2) There are however very little information of the effect from specific foot exercise as an imperative part of exercise program...... adolescent females (3). Soft foot orhtoses in addition to an exercise program resulted in significantly greater improvements in pain than treatment with flat insoles and exercises over eight weeks. A study from 2004 by Wiener-Ogilvie & Jones (4) found however no difference in outcome between 8 weeks...... to PFPS patients. The purpose of this prospective single blinded randomised study was to determine the effectiveness of a standardized foot training program combined with foot orthoses in patients with patellofemoral pain. This treatment was additional to a regular conservative patellofemoral regime...

  18. EFFECT OF EXTRINSIC REWARDS ON MOTIVATION.

    Science.gov (United States)

    GLADSTONE, ROY

    THE SPECIFIC PROBLEM WAS WHETHER HUMANS, AFTER HAVING BEEN TRAINED ON A GIVEN REWARD SCHEDULE TO ACT IN A GIVEN WAY IN GIVEN CIRCUMSTANCES, WILL EXHIBIT FIXED EXTINCTION BEHAVIOR REGARDLESS OF THE DIFFERENCES BETWEEN THE TRAINING AND THE EXTINCTION PERIODS. SUBJECTS WERE 360 COLLEGE STUDENTS WHO HAD VOLUNTEERED FOR THE EXPERIMENT. AN APPARATUS WAS…

  19. Intrinsic and extrinsic spin-orbit torques from first principles

    International Nuclear Information System (INIS)

    Geranton, Guillaume

    2017-01-01

    This thesis attempts to shed light on the microscopic mechanisms underlying the current-induced magnetic torques in ferromagnetic heterostructures. We have developed first principles methods aiming at the accurate and effcient calculation of the so-called spin-orbit torques (SOTs) in magnetic thin films. The emphasis of this work is on the impurity-driven extrinsic SOTs. The main part of this thesis is dedicated to the development of a formalism for the calculation of the SOTs within the Korringa-Kohn-Rostoker (KKR) method. The impurity-induced transitions rates are obtained from first principles and their effect on transport properties is treated within the Boltzmann formalism. The developed formalism provides a mean to compute the SOTs beyond the conventional constant relaxation time approximation. We first apply our formalism to the investigation of FePt/Pt and Co/Cu bilayers in the presence of defects and impurities. Our results hint at a crucial dependence of the torque on the type of disorder present in the films, which we explain by a complex interplay of several competing Fermi surface contributions to the SOT. Astonishingly, specific defect distributions or doping elements lead respectively to an increase or a sign change of the torque, which can not be explained on the basis of simple models. We also compute the intrinsic SOT induced by electrical and thermal currents within the full potential linearized augmented plane-wave method. Motivated by recent experimental works, we then investigate the microscopic origin of the SOT in a Ag 2 Bi-terminated Ag film grown on ferromagnetic Fe(110). We find that the torque in that system can not be explained solely by the spin-orbit coupling in the Ag 2 Bi alloy, and instead results from the spin-orbit coupling in all regions of the film.Finally, we predict a large SOT in Fe/Ge bilayers and suggest that semiconductor substrates might be a promising alternative to heavy metals for the development of SOT-based magnetic

  20. Intrinsic and extrinsic spin-orbit torques from first principles

    Energy Technology Data Exchange (ETDEWEB)

    Geranton, Guillaume

    2017-09-01

    This thesis attempts to shed light on the microscopic mechanisms underlying the current-induced magnetic torques in ferromagnetic heterostructures. We have developed first principles methods aiming at the accurate and effcient calculation of the so-called spin-orbit torques (SOTs) in magnetic thin films. The emphasis of this work is on the impurity-driven extrinsic SOTs. The main part of this thesis is dedicated to the development of a formalism for the calculation of the SOTs within the Korringa-Kohn-Rostoker (KKR) method. The impurity-induced transitions rates are obtained from first principles and their effect on transport properties is treated within the Boltzmann formalism. The developed formalism provides a mean to compute the SOTs beyond the conventional constant relaxation time approximation. We first apply our formalism to the investigation of FePt/Pt and Co/Cu bilayers in the presence of defects and impurities. Our results hint at a crucial dependence of the torque on the type of disorder present in the films, which we explain by a complex interplay of several competing Fermi surface contributions to the SOT. Astonishingly, specific defect distributions or doping elements lead respectively to an increase or a sign change of the torque, which can not be explained on the basis of simple models. We also compute the intrinsic SOT induced by electrical and thermal currents within the full potential linearized augmented plane-wave method. Motivated by recent experimental works, we then investigate the microscopic origin of the SOT in a Ag{sub 2}Bi-terminated Ag film grown on ferromagnetic Fe(110). We find that the torque in that system can not be explained solely by the spin-orbit coupling in the Ag{sub 2}Bi alloy, and instead results from the spin-orbit coupling in all regions of the film.Finally, we predict a large SOT in Fe/Ge bilayers and suggest that semiconductor substrates might be a promising alternative to heavy metals for the development of SOT

  1. Computing effective properties of nonlinear structures exposed to strong high-frequency loading at multiple frequencies

    DEFF Research Database (Denmark)

    Thomsen, Jon Juel

    2006-01-01

    Effects of strong high-frequency excitation at multiple frequencies (multi-HFE) are analyzed for a class of generally nonlinear systems. The effects are illustrated for a simple pendulum system with a vibrating support, and for a parametrically excited flexible beam. For the latter, theoretical...

  2. Extrinsic Contribution and Instability Properties in Lead-Based and Lead-Free Piezoceramics

    Directory of Open Access Journals (Sweden)

    José Eduardo García

    2015-11-01

    Full Text Available Piezoceramic materials generally exhibit a notable instability of their functional properties when they work under real external conditions. This undesirable effect, known as nonlinear behavior, is mostly associated with the extrinsic contribution to material response. In this article, the role of the ferroelectric domain walls’ motion in the nonlinear response in the most workable lead-based and lead-free piezoceramics is reviewed. Initially, the extrinsic origin of the nonlinear response is discussed in terms of the temperature dependence of material response. The influence of the crystallographic phase and of the phase boundaries on the material response are then reviewed. Subsequently, the impact of the defects created by doping in order to control the extrinsic contribution is discussed as a way of tuning material properties. Finally, some aspects related to the grain-size effect on the nonlinear response of piezoceramics are surveyed.

  3. Predictors of employment in schizophrenia: The importance of intrinsic and extrinsic motivation.

    Science.gov (United States)

    Reddy, L Felice; Llerena, Katiah; Kern, Robert S

    2016-10-01

    Unemployment is a primary functional deficit for the majority of adults with schizophrenia. Research indicates that over two-thirds of adults living in the community with schizophrenia are unemployed. Despite effective programs to assist with job identification and placement, the ability to attain and maintain employment remains a pressing concern. A contributing factor that may be relevant but has received little attention in the work rehabilitation literature is motivation. People with schizophrenia show marked deficits in both intrinsic and extrinsic motivation but these deficits have not been directly examined in relation to work outcomes. The present study sought to examine the relationship between intrinsic and extrinsic motivation and work outcome among a sample of 65 adults with schizophrenia enrolled in a supported employment program. One-third of the participants in the study obtained work. Intrinsic motivation related to valuing and feeling useful in a work role significantly predicted who would obtain employment. Extrinsic motivation related to gaining rewards and avoiding obstacles showed a non-significant trend-level relationship such that workers had higher extrinsic motivation than nonworkers. These findings highlight the importance of considering both intrinsic and extrinsic motivation in work-related interventions and supported employment for individuals with schizophrenia. The results are discussed in terms of clinical implications for improving rehabilitation and occupational outcomes in schizophrenia. Published by Elsevier B.V.

  4. SUNYAEV-ZEL'DOVICH EFFECT OBSERVATIONS OF STRONG LENSING GALAXY CLUSTERS: PROBING THE OVERCONCENTRATION PROBLEM

    International Nuclear Information System (INIS)

    Gralla, Megan B.; Gladders, Michael D.; Marrone, Daniel P.; Bayliss, Matthew; Carlstrom, John E.; Greer, Christopher; Hennessy, Ryan; Koester, Benjamin; Leitch, Erik; Sharon, Keren; Barrientos, L. Felipe; Bonamente, Massimiliano; Bulbul, Esra; Hasler, Nicole; Culverhouse, Thomas; Hawkins, David; Lamb, James; Gilbank, David G.; Joy, Marshall; Miller, Amber

    2011-01-01

    We have measured the Sunyaev-Zel'dovich (SZ) effect for a sample of 10 strong lensing selected galaxy clusters using the Sunyaev-Zel'dovich Array (SZA). The SZA is sensitive to structures on spatial scales of a few arcminutes, while the strong lensing mass modeling constrains the mass at small scales (typically <30''). Combining the two provides information about the projected concentrations of the strong lensing clusters. The Einstein radii we measure are twice as large as expected given the masses inferred from SZ scaling relations. A Monte Carlo simulation indicates that a sample randomly drawn from the expected distribution would have a larger median Einstein radius than the observed clusters about 3% of the time. The implied overconcentration has been noted in previous studies and persists for this sample, even when we take into account that we are selecting large Einstein radius systems, suggesting that the theoretical models still do not fully describe the observed properties of strong lensing clusters.

  5. Extrinsic labelling of zinc and calcium in bread

    International Nuclear Information System (INIS)

    Fredlund, Kerstin; Rossander-Hulthen, Lena; Isaksson, Mats; Almgren, Annette; Sandberg, A.-S.

    2002-01-01

    This study investigated the effect of different means of extrinsic administration of 65 Zn and 47 Ca in white wheat flour bread on the measured absorption. Eight healthy subjects were served 80 g of labelled bread as a standardized breakfast after an overnight fast on three occasions. Extrinsic labelling of the meals with 65 Zn and 47 Ca was done in three ways: (a) by adding the isotopes to the bread 16 h before it was served, (b) by adding the isotopes shortly before serving or (c) by adding the isotopes to the water used in dough making. Zinc and calcium chloride corresponding to 3.2 mg (49 μmol) zinc and 275 mg (6.9 mmol) calcium in one portion were added to the dough. Whole-body retention was measured by whole-body counting. The fractional absorption of zinc was (a) 0.243±0.122, (b) 0.217±0.101 and (c) 0.178±0.063 (mean±SD), and the fractional absorption of calcium (expressed as calcium retention on day 7) was (a) 0.351±0.108, (b) 0.357±0.131 and (c) 0.334±0.117 (mean±SD). No significant difference (p>0.05) was seen between the different ways for either zinc nor calcium

  6. Do intrinsic and extrinsic motivation relate differently to employee outcomes?

    OpenAIRE

    Kuvaas, Bard; Buch, Robert; Weibel, Antoinette; Dysvik, Anders; Nerstad, Christina

    2017-01-01

    In most theories that address how individual financial incentives affect work performance, researchers have assumed that two types of motivation—intrinsic and extrinsic—mediate the relationship between incentives and performance. Empirically, however, extrinsic motivation is rarely investigated. To explore the predictive validity of these theories of intrinsic and extrinsic motivation in work settings, we tested how both intrinsic and extrinsic motivation affected supervisor-ra...

  7. Using strong nonlinearity and high-frequency vibrations to control effective properties of discrete elastic waveguides

    DEFF Research Database (Denmark)

    Lazarov, Boyan Stefanov; Thomsen, Jon Juel; Snaeland, Sveinn Orri

    2008-01-01

    The aim of this article is to investigate how highfrequency (HF) excitation, combined with strong nonlinear elastic material behavior, influences the effective material or structural properties for low-frequency excitation and wave propagation. The HF effects are demonstrated on discrete linear...... spring-mass chains with non-linear inclusions. The presented analytical and numerical results suggest that the effective material properties can easily be altered by establishing finite amplitude HF standing waves in the non-linear regions of the chain....

  8. Effective hadronic lagrangian in the strong coupling expansion of lattice QCD with Susskind fermions

    International Nuclear Information System (INIS)

    Azakov, S.I.; Aliev, E.S.

    1987-12-01

    The effective hadronic action in lattice QCD with U(N) and SU(N) gauge groups and with Susskind fermions is constructed in the framework of the strong coupling approximation. For arbitrary finite (odd) N (in particular N=3) we find an effective potential, vacuum expectation value of the (χ-barχ) and an effective action for the physical meson field π(x). (author). 19 refs

  9. The Role of Extrinsic Rewards and Cue-Intention Association in Prospective Memory in Young Children

    NARCIS (Netherlands)

    Sheppard, D.P.; Kretschmer, A.; Knispel, E.; Vollert, B.; Altgassen, A.M.

    2015-01-01

    The current study examined, for the first time, the effect of cue-intention association, as well as the effects of promised extrinsic rewards, on prospective memory in young children, aged 5-years-old (n = 39) and 7-years-old (n = 40). Children were asked to name pictures for a toy mole, whilst also

  10. Planning, Instruction, and Assessment: Effective Teaching Practices. James H. Stronge Research-to-Practice Series

    Science.gov (United States)

    Grant, Leslie W.; Hindman, Jennifer; Stronge, James H.

    2010-01-01

    This entry in the James H. Stronge Research-to-Practice Series focuses on specific strategies teachers can use to improve the quality of their instruction. Studies have shown teacher quality to be the top indicator of student achievement, with the effects of good teachers apparent even as students move on to successive grades. In this book, Grant,…

  11. Engineering the Dynamics of Effective Spin-Chain Models for Strongly Interacting Atomic Gases

    DEFF Research Database (Denmark)

    Volosniev, A. G.; Petrosyan, D.; Valiente, M.

    2015-01-01

    We consider a one-dimensional gas of cold atoms with strong contact interactions and construct an effective spin-chain Hamiltonian for a two-component system. The resulting Heisenberg spin model can be engineered by manipulating the shape of the external confining potential of the atomic gas. We...

  12. Effects of interaction imbalance in a strongly repulsive one-dimensional Bose gas

    DEFF Research Database (Denmark)

    Barfknecht, Rafael Emilio; Zinner, Nikolaj Thomas; Foerster, Angela

    2018-01-01

    We calculate the spatial distributions and the dynamics of a few-body two-component strongly interacting Bose gas confined to an effectively one-dimensional trapping potential. We describe the densities for each component in the trap for different interaction and population imbalances. We calculate...

  13. Parity violation effects in the hydrogen atom in the field of a strong electromagnetic wave

    International Nuclear Information System (INIS)

    Labzovsky, L.N.; Mitrushchenkov, A.O.

    1989-01-01

    The parity violation effects in the hydrogen atom in a strong electromagnetic laser field are considered. It is shown that there is the possibility of hyperrate measurements of different constants of the weak interaction in the hydrogen magnetic resonance experiments. (orig.)

  14. Effects of interaction imbalance in a strongly repulsive one-dimensional Bose gas

    DEFF Research Database (Denmark)

    Barfknecht, Rafael Emilio; Zinner, Nikolaj Thomas; Foerster, Angela

    2018-01-01

    We calculate the spatial distributions and the dynamics of a few-body two-component strongly interacting Bose gas confined to an effectively one-dimensional trapping potential. We describe the densities for each component in the trap for different interaction and population imbalances. We calcula...

  15. Non-Oberbeck-Boussinesq effects in strongly turbulent Rayleigh-Bénard convection

    NARCIS (Netherlands)

    Ahlers, Günter; Brown, Eric; Fontenele Araujo Junior, F.; Funfschilling, Denis; Grossmann, Siegfried; Lohse, Detlef

    2006-01-01

    Non-Oberbeck–Boussinesq (NOB) effects on the Nusselt number $Nu$ and Reynolds number $\\hbox{\\it Re}$ in strongly turbulent Rayleigh–Bénard (RB) convection in liquids were investigated both experimentally and theoretically. In the experiments the heat current, the temperature difference, and the

  16. Heavy quark mass effects and improved tests of the flavor independence of strong interactions

    Energy Technology Data Exchange (ETDEWEB)

    Burrows, P.N. [Univ. of Oxford (United Kingdom); SLD Collaboration

    1998-08-01

    A review is given of latest results on tests of the flavor independence of strong interactions. Heavy quark mass effects are evident in the data and are now taken into account at next-to-leading order in QCD perturbation theory. The strong-coupling ratios {alpha}{sub s}{sup b}/{alpha}{sub s}{sup uds} and {alpha}{sub s}{sup c}/{alpha}{sub s}{sup uds} are found to be consistent with unity. Determinations of the b-quark mass m{sub b} (M{sub Z}) are discussed.

  17. Strong interaction effects in high-Z K sup minus atoms

    Energy Technology Data Exchange (ETDEWEB)

    Batty, C.J.; Eckhause, M.; Gall, K.P.; Guss, P.P.; Hertzog, D.W.; Kane, J.R.; Kunselman, A.R.; Miller, J.P.; O' Brien, F.; Phillips, W.C.; Powers, R.J.; Roberts, B.L.; Sutton, R.B.; Vulcan, W.F.; Welsh, R.E.; Whyley, R.J.; Winter, R.G. (Rutherford-Appleton Laboratory, Chilton, Didcot OX11 0QX, United Kingdom (GB) College of William and Mary, Williamsburg, Virginia 23185 Boston University, Boston, Massachusetts 02215 University of Wyoming, Laramie, Wyoming 82071 California Institute of Technology, Pasadena, California 91125 Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213)

    1989-11-01

    A systematic experimental study of strong interaction shifts, widths, and yields from high-{ital Z} kaonic atoms is reported. Strong interaction effects for the {ital K}{sup {minus}}(8{r arrow}7) transition were measured in U, Pb, and W, and the {ital K}{sup {minus}}(7{r arrow}6) transition in W was also observed. This is the first observation of two measurably broadened and shifted kaonic transitions in a single target and thus permitted the width of the upper state to be determined directly, rather than being inferred from yield data. The results are compared with optical-model calculations.

  18. Extrinsic and intrinsic determinants of nerve regeneration

    Directory of Open Access Journals (Sweden)

    Toby A. Ferguson

    2011-01-01

    Full Text Available After central nervous system (CNS injury axons fail to regenerate often leading to persistent neurologic deficit although injured peripheral nervous system (PNS axons mount a robust regenerative response that may lead to functional recovery. Some of the failures of CNS regeneration arise from the many glial-based inhibitory molecules found in the injured CNS, whereas the intrinsic regenerative potential of some CNS neurons is actively curtailed during CNS maturation and limited after injury. In this review, the molecular basis for extrinsic and intrinsic modulation of axon regeneration within the nervous system is evaluated. A more complete understanding of the factors limiting axonal regeneration will provide a rational basis, which is used to develop improved treatments for nervous system injury.

  19. Efficacy test of a toothpaste in reducing extrinsic dental stain

    Science.gov (United States)

    Agustanti, A.; Ramadhani, S. A.; Adiatman, M.; Rahardjo, A.; Callea, M.; Yavuz, I.; Maharani, D. A.

    2017-08-01

    This clinical trial compared the external dental stain reduction achieved by tested toothpaste versus placebo in adult patients. In this double-blind, parallel, randomised clinical trial, 45 female volunteers with a mean age of 20 years old were included. All study subjects front teeth were topically applicated with Silver Diamine Fluoride (SDF) to create external dental stains. Subjects were randomized into test (n=22) and control (n=23) groups. Toothpastes were used for two days to analyse the effects of removing external stains on the labial surfaces of all anterior teeth. VITA Easyshade Advance 4.0 was used to measure dental extrinsic stains changes. The analysis showed statistically significant efficacy of the tested toothpaste in reducing external dental stain caused by SDF, comparing to the placebo toothpaste, after one and two days of usage. The tested toothpaste was effective in reducing dental stain.

  20. Auger effect in the presence of strong x-ray pulses

    International Nuclear Information System (INIS)

    Liu Jicai; Sun Yuping; Wang Chuankui; Aagren, Hans; Gel'mukhanov, Faris

    2010-01-01

    We study the role of propagation of strong x-ray free-electron laser pulses on the Auger effect. When the system is exposed to a strong x-ray pulse the stimulated emission starts to compete with the Auger decay. As an illustration we present numerical results for Ar gas with the frequency of the incident x-ray pulse tuned in the 2p 3/2 -4s resonance. It is shown that the pulse propagation is accompanied by two channels of amplified spontaneous emission, 4s-2p 3/2 and 3s-2p 3/2 , which reshape the pulse when the system is inverted. The population inversion is quenched for longer propagation distances where lasing without inversion enhances the Stokes component. The results of simulations show that the propagation of the strong x-ray pulses affect intensively the Auger branching ratio.

  1. The Influence of Extrinsic and Intrinsic Motivation on Employee Perfomance at Bank Sulut Manado

    OpenAIRE

    Mundung, Shintya Ervina Donna; Pangemanan, Sifrid Pangemanan

    2015-01-01

    Motivation is the basic desire why people do job and performance of employee have a strong related with employee's motivation and the purpose of this study was to investigate how two variable of motivation (extrinsic and intrinsic motivation) based on Herzberg (1966) that affect employee performance, A conceptual framework based on Human Resources Management, was utilized to form 2 hypotheses predicting the causality between the different variables. After validating the scale to data gathered...

  2. Intrinsic vs. extrinsic influences on life history expression: metabolism and parentally induced temperature influences on embryo development rate

    Science.gov (United States)

    Martin, Thomas E.; Ton, Riccardo; Nikilson, Alina

    2013-01-01

    Intrinsic processes are assumed to underlie life history expression and trade-offs, but extrinsic inputs are theorised to shift trait expression and mask trade-offs within species. Here, we explore application of this theory across species. We do this based on parentally induced embryo temperature as an extrinsic input, and mass-specific embryo metabolism as an intrinsic process, underlying embryonic development rate. We found that embryonic metabolism followed intrinsic allometry rules among 49 songbird species from temperate and tropical sites. Extrinsic inputs via parentally induced temperatures explained the majority of variation in development rates and masked a relationship with metabolism; metabolism explained a minor proportion of the variation in development rates among species, and only after accounting for temperature effects. We discuss evidence that temperature further obscures the expected interspecific trade-off between development rate and offspring quality. These results demonstrate the importance of considering extrinsic inputs to trait expression and trade-offs across species.

  3. Intrinsic and Extrinsic Motivation: Evaluating Benefits and Drawbacks from College Instructors' Perspectives

    Science.gov (United States)

    Lei, Simon A.

    2010-01-01

    A growing body of literature has been examined and discussed the effects of intrinsic and extrinsic motivation on student learning at the college level. Intrinsically motivated individuals have been able to develop high regards for learning various types of course information without the inclusion of external rewards or reinforcements. In…

  4. Tangible and Intangible Rewards and Employee Creativity: The Mediating Role of Situational Extrinsic Motivation

    Science.gov (United States)

    Yoon, Hye Jung; Sung, Sun Young; Choi, Jin Nam; Lee, Kyungmook; Kim, Seongsu

    2015-01-01

    This study examined the effects of tangible and intangible forms of creativity-contingent rewards on employee creativity. Situation-specific intrinsic and extrinsic motivations were proposed as mediators of the reward-creativity link. Based on data collected from 271 employees and their supervisors, results revealed the following: (a) intangible…

  5. The Parachute Ankle Brace: Entanglements and Injuries After Controlling for Extrinsic Risk Factors

    Science.gov (United States)

    2007-03-10

    Preventive Medicine THE PARACHUTE ANKLE BRACE: ENTANGLEMENTS AND INJURIES AFTER CONTROLLING FOR EXTRINSIC RISK...Amoroso P.J. (2005). Effectiveness of an external ankle brace in reducing parachute-related ankle injuries . Injury Prevention . 11: 163- 168. 25...M. (1994). The efficacy of a semirigid ankle stabilizer to reduce acute ankle injury in basketball . American Journal of Sports Medicine. 22:

  6. Extrinsic doping of CuGaSe2 single crystals

    Science.gov (United States)

    Schön, J. H.

    2000-02-01

    Technological applications of semiconductors depend critically on the ability to dope them. Single crystals of CuGaSe2 were doped during crystal growth either by a post-growth diffusion step or by ion-implantation, in order to study the limits of extrinsic doping. The electrical and optical properties of the doped samples are analysed by Hall effect and photoluminescence (PL) measurements. The carrier concentration at room temperature can be adjusted between 2 × 1019 cm-3 (p-type) and 1017 cm-3 (n-type). Various donor and acceptor levels are identified and ascribed to dopant-induced point defects taking into account the dopant concentration and/or the post-growth treatment of the single crystals.

  7. Strong coupling electrostatics for randomly charged surfaces: antifragility and effective interactions.

    Science.gov (United States)

    Ghodrat, Malihe; Naji, Ali; Komaie-Moghaddam, Haniyeh; Podgornik, Rudolf

    2015-05-07

    We study the effective interaction mediated by strongly coupled Coulomb fluids between dielectric surfaces carrying quenched, random monopolar charges with equal mean and variance, both when the Coulomb fluid consists only of mobile multivalent counterions and when it consists of an asymmetric ionic mixture containing multivalent and monovalent (salt) ions in equilibrium with an aqueous bulk reservoir. We analyze the consequences that follow from the interplay between surface charge disorder, dielectric and salt image effects, and the strong electrostatic coupling that results from multivalent counterions on the distribution of these ions and the effective interaction pressure they mediate between the surfaces. In a dielectrically homogeneous system, we show that the multivalent counterions are attracted towards the surfaces with a singular, disorder-induced potential that diverges logarithmically on approach to the surfaces, creating a singular but integrable counterion density profile that exhibits an algebraic divergence at the surfaces with an exponent that depends on the surface charge (disorder) variance. This effect drives the system towards a state of lower thermal 'disorder', one that can be described by a renormalized temperature, exhibiting thus a remarkable antifragility. In the presence of an interfacial dielectric discontinuity, the singular behavior of counterion density at the surfaces is removed but multivalent counterions are still accumulated much more strongly close to randomly charged surfaces as compared with uniformly charged ones. The interaction pressure acting on the surfaces displays in general a highly non-monotonic behavior as a function of the inter-surface separation with a prominent regime of attraction at small to intermediate separations. This attraction is caused directly by the combined effects from charge disorder and strong coupling electrostatics of multivalent counterions, which dominate the surface-surface repulsion due to

  8. The dark side of monetary incentive: how does extrinsic reward crowd out intrinsic motivation.

    Science.gov (United States)

    Ma, Qingguo; Jin, Jia; Meng, Liang; Shen, Qiang

    2014-02-12

    It was widely believed that incentives could effectively enhance the motivation of both students and employees. However, psychologists reported that extrinsic reward actually could undermine individuals' intrinsic motivation to a given interesting task, which challenged viewpoints from traditional incentive theories. Numerous studies have been carried out to test and explain the undermining effect; however, the neural basis of this effect is still elusive. Here, we carried out an electrophysiological study with a simple but interesting stopwatch task to explore to what extent the performance-based monetary reward undermines individuals' intrinsic motivation toward the task. The electrophysiological data showed that the differentiated feedback-related negativity amplitude toward intrinsic success failure divergence was prominently reduced once the extrinsic reward was imposed beforehand. However, such a difference was not observed in the control group, in which no extrinsic reward was provided throughout the experiment. Furthermore, such a pattern was not observed for P300 amplitude. Therefore, the current results indicate that extrinsic reward demotivates the intrinsic response of individuals toward success-failure outcome, which was reflected in the corresponding reduced motivational-related differentiated feedback-related negativity, but not in amplitude of P300.

  9. Extrinsic grouping factors in motion-induced blindness

    Science.gov (United States)

    2018-01-01

    We investigated how various grouping factors altered subjective disappearances of the individual targets in the motion-induced blindness display. The latter relies on a moving mask to render highly salient static targets temporarily subjectively invisible. Specifically, we employed two extrinsic grouping factors, the connectedness and the common region, and examined whether their presence would make targets more resilient against the suppression. In addition, we investigated whether the presence of an illusory Kanizsa triangle would affect the suppression of the inducing Pac-Man elements. We quantified the perceptual dynamics using the proportion of the disappearance time (this indicates whether targets became more resilient against the suppression), and the proportion of simultaneous disappearance and reappearance events (characterizes the tendency for the targets to disappear or reappear as a group). We report that a single mask that encompassed all targets (a common region grouping) significantly increased the proportion of simultaneous disappearance and reappearance events, but had no effect on the proportion of the disappearance time. In contrast, a line that connected two targets significantly decreased the total invisibility time, but had no impact on the simultaneity of the disappearance and reappearance events. We found no statistically significant effect of the presence of the illusory Kanizsa triangle on either measure. Finally, we found no interaction either between the common region and the connectedness or between the common region and the presence of the illusory Kanizsa triangle. Our results indicate that extrinsic grouping factors might influence the perception differently than the intrinsic ones and highlight the importance of using several measures to characterize the perceptual dynamics, as various grouping factors might affect it differentially. PMID:29381747

  10. Empty creditors and strong shareholders: The real effects of credit risk trading. Second draft

    OpenAIRE

    Colonnello, Stefano; Efing, Matthias; Zucchi, Francesca

    2016-01-01

    Credit derivatives give creditors the possibility to transfer debt cash flow rights to other market participants while retaining control rights. We use the market for credit default swaps (CDSs) as a laboratory to show that the real effects of such debt unbundling crucially hinge on shareholder bargaining power. We find that creditors buy more CDS protection when facing strong shareholders to secure themselves a valuable outside option in distressed renegotiations. After the start of CDS trad...

  11. [Effects of strong reductive approach on remediation of degraded facility vegetable soil].

    Science.gov (United States)

    Zhu, Tong-Bin; Meng, Tian-Zhu; Zhang, Jin-Bo; Cai, Zu-Cong

    2013-09-01

    High application rate of chemical fertilizers and unreasonable rotation in facility vegetable cultivation can easily induce the occurrence of soil acidification, salinization, and serious soil-borne diseases, while to quickly and effectively remediate the degraded facility vegetable soil can considerably increase vegetable yield and farmers' income. In this paper, a degraded facility vegetable soil was amended with 0, 3.75, 7.50, and 11.3 t C x hm(-2) of air-dried alfalfa and flooded for 31 days to establish a strong reductive environment, with the variations of soil physical and chemical properties and the cucumber yield studied. Under the reductive condition, soil Eh dropped quickly below 0 mV, accumulated soil NO3(-) was effectively eliminated, soil pH was significantly raised, and soil EC was lowered, being more evident in higher alfalfa input treatments. After treated with the strong reductive approach, the cucumber yield in the facility vegetable field reached 53.3-57.9 t x hm(-2), being significantly higher than that in un-treated facility vegetable field in last growth season (10.8 t x hm(-2)). It was suggested that strong reductive approach could effectively remediate the degraded facility vegetable soil in a short term.

  12. Strong Stability Preserving Explicit Runge--Kutta Methods of Maximal Effective Order

    KAUST Repository

    Hadjimichael, Yiannis

    2013-07-23

    We apply the concept of effective order to strong stability preserving (SSP) explicit Runge--Kutta methods. Relative to classical Runge--Kutta methods, methods with an effective order of accuracy are designed to satisfy a relaxed set of order conditions but yield higher order accuracy when composed with special starting and stopping methods. We show that this allows the construction of four-stage SSP methods with effective order four (such methods cannot have classical order four). However, we also prove that effective order five methods---like classical order five methods---require the use of nonpositive weights and so cannot be SSP. By numerical optimization, we construct explicit SSP Runge--Kutta methods up to effective order four and establish the optimality of many of them. Numerical experiments demonstrate the validity of these methods in practice.

  13. Using strong nonlinearity and high-frequency vibrations to control effective mechanical stiffness

    DEFF Research Database (Denmark)

    Thomsen, Jon Juel

    2008-01-01

    High-frequency excitation (HFE) can be used to change the effective stiffness of an elastic structure, and related quanti-ties such as resonance frequencies, wave speed, buckling loads, and equilibrium states. There are basically two ways to do this: By using parametrical HFE (with or without non...... the method of direct separation of motions with results of a modified multiple scales ap-proach, valid also for strong nonlinearity, the stiffening ef-fect is predicted for a generic 1-dof system, and results are tested against numerical simulation and ((it is planned)) laboratory experiments....

  14. Three-loop Standard Model effective potential at leading order in strong and top Yukawa couplings

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Stephen P. [Santa Barbara, KITP

    2014-01-08

    I find the three-loop contribution to the effective potential for the Standard Model Higgs field, in the approximation that the strong and top Yukawa couplings are large compared to all other couplings, using dimensional regularization with modified minimal subtraction. Checks follow from gauge invariance and renormalization group invariance. I also briefly comment on the special problems posed by Goldstone boson contributions to the effective potential, and on the numerical impact of the result on the relations between the Higgs vacuum expectation value, mass, and self-interaction coupling.

  15. Attosecond counter-rotating-wave effect in xenon driven by strong fields

    Science.gov (United States)

    Anand, M.; Pabst, Stefan; Kwon, Ojoon; Kim, Dong Eon

    2017-05-01

    We investigate the subfemtosecond dynamics of a highly excited xenon atom coherently driven by a strong control field at which the Rabi frequency of the system is comparable to the frequency of a driving laser. The widely used rotating-wave approximation breaks down at such fields, resulting in features such as the counter-rotating-wave (CRW) effect. We present a time-resolved observation of the CRW effect in the highly excited 4 d-1n p xenon using attosecond transient absorption spectroscopy. Time-dependent many-body theory confirms the observation and explains the various features of the absorption spectrum seen in experiment.

  16. Proprioceptive bimanual test in intrinsic and extrinsic coordinates

    Directory of Open Access Journals (Sweden)

    Riccardo eIandolo

    2015-02-01

    Full Text Available Is there any difference between matching the position of the hands by asking the subjects to move them to the same spatial location or to mirror symmetric locations with respect to the body midline? If the motion of the hands were planned in the extrinsic space, the mirror symmetric task would imply an additional challenge, because we would need to flip the coordinates of the target on the other side of the workspace. Conversely, if the planning were done in intrinsic coordinates, in order to move both hands to the same spot in the workspace, we should compute different joint angles for each arm. Even if both representations were available to the subjects, the two tasks might lead to different results, providing some cue on the organization of the body schema. In order to answer such questions, the middle fingertip of the non-dominant hand of a population of healthy subjects was passively moved by a manipulandum to 20 different target locations. Subjects matched these positions with the middle fingertip of their dominant hand. For most subjects the matching accuracy was higher in the extrinsic modality both in terms of systematic error and variability, even for the target locations in which the configuration of the arms was the same for both modalities. This suggests that the matching performance of the subjects could be determined not only by proprioceptive information, but also by the cognitive representation of the task: expressing the goal as reaching for the physical location of the hand in space is apparently more effective than requiring to match the proprioceptive representation of joint angles.

  17. Interaction effects in a microscopic quantum wire model with strong spin-orbit interaction

    Science.gov (United States)

    Winkler, G. W.; Ganahl, M.; Schuricht, D.; Evertz, H. G.; Andergassen, S.

    2017-06-01

    We investigate the effect of strong interactions on the spectral properties of quantum wires with strong Rashba spin-orbit (SO) interaction in a magnetic field, using a combination of matrix product state and bosonization techniques. Quantum wires with strong Rashba SO interaction and magnetic field exhibit a partial gap in one-half of the conducting modes. Such systems have attracted wide-spread experimental and theoretical attention due to their unusual physical properties, among which are spin-dependent transport, or a topological superconducting phase when under the proximity effect of an s-wave superconductor. As a microscopic model for the quantum wire we study an extended Hubbard model with SO interaction and Zeeman field. We obtain spin resolved spectral densities from the real-time evolution of excitations, and calculate the phase diagram. We find that interactions increase the pseudo gap at k = 0 and thus also enhance the Majorana-supporting phase and stabilize the helical spin order. Furthermore, we calculate the optical conductivity and compare it with the low energy spiral Luttinger liquid result, obtained from field theoretical calculations. With interactions, the optical conductivity is dominated by an excotic excitation of a bound soliton-antisoliton pair known as a breather state. We visualize the oscillating motion of the breather state, which could provide the route to their experimental detection in e.g. cold atom experiments.

  18. Charging-delay effect on longitudinal dust acoustic shock wave in strongly coupled dusty plasma

    International Nuclear Information System (INIS)

    Ghosh, Samiran; Gupta, M.R.

    2005-01-01

    Taking into account the charging-delay effect, the nonlinear propagation characteristics of longitudinal dust acoustic wave in strongly coupled collisional dusty plasma described by generalized hydrodynamic model have been investigated. In the 'hydrodynamic limit', a Korteweg-de Vries Burger (KdVB) equation with a damping term arising due to dust-neutral collision is derived in which the Burger term is proportional to the dissipation due to dust viscosity through dust-dust correlation and charging-delay-induced anomalous dissipation. On the other hand, in the 'kinetic limit', a KdVB equation with a damping term and a nonlocal nonlinear forcing term arising due to memory-dependent strong correlation effect of dust fluid is derived in which the Burger term depends only on the charging-delay-induced dissipation. Numerical solution of integrodifferential equations reveals that (i) dissipation due to dust viscosity and principally due to charging delay causes excitation of the longitudinal dust acoustic shock wave in strongly coupled dusty plasma and (ii) dust-neutral collision does not appear to play any direct role in shock formation. The condition for the generation of shock is also discussed briefly

  19. Challenges in inflationary magnetogenesis: Constraints from strong coupling, backreaction, and the Schwinger effect

    Science.gov (United States)

    Sharma, Ramkishor; Jagannathan, Sandhya; Seshadri, T. R.; Subramanian, Kandaswamy

    2017-10-01

    Models of inflationary magnetogenesis with a coupling to the electromagnetic action of the form f2Fμ νFμ ν , are known to suffer from several problems. These include the strong coupling problem, the backreaction problem and also strong constraints due to the Schwinger effect. We propose a model which resolves all these issues. In our model, the coupling function, f , grows during inflation and transits to a decaying phase post-inflation. This evolutionary behavior is chosen so as to avoid the problem of strong coupling. By assuming a suitable power-law form of the coupling function, we can also neglect backreaction effects during inflation. To avoid backreaction post-inflation, we find that the reheating temperature is restricted to be below ≈1.7 ×104 GeV . The magnetic energy spectrum is predicted to be nonhelical and generically blue. The estimated present day magnetic field strength and the corresponding coherence length taking reheating at the QCD epoch (150 MeV) are 1.4 ×10-12 G and 6.1 ×10-4 Mpc , respectively. This is obtained after taking account of nonlinear processing over and above the flux-freezing evolution after reheating. If we consider also the possibility of a nonhelical inverse transfer, as indicated in direct numerical simulations, the coherence length and the magnetic field strength are even larger. In all cases mentioned above, the magnetic fields generated in our models satisfy the γ -ray bound below a certain reheating temperature.

  20. Are there metallic traces in black extrinsic dental stain?

    Science.gov (United States)

    Parnas, Limor; Chevion, Mordechai; Berenshtein, Eduard; Faibis, Sarit; Moskovitz, Moti

    2013-05-01

    The detection of ferric ions in samples of black extrinsic dental stain led to the idea that it is comprised of insoluble ferric compounds. The present study examined the chemical composition of black extrinsic dental stain. Plaque was collected from 17 children with black extrinsic dental stain (study group A) and from 15 children without black extrinsic stain (control group), using sterile graphite curettes; and from 4 children with black extrinsic stain (study group B), using a standard sterile metal curette. Samples were analyzed with a scanning electron microscope (SEM) and subjected to quantitative chemical analysis (energy dispersive spectrometry). Except for calcium and phosphorus levels, no significant differences were found between the chemical composition of black extrinsic dental stain and dental plaque. Metallic ions were not detected in samples collected with a graphite curette (study group A), but were detected in samples collected with a metal curette (study group B). Metallic ions do not seem to be the origin of black extrinsic dental stain. Previous reports of the presence of metallic ions are probably due to contamination of the samples by the collection method.

  1. Extended Parrondo's game and Brownian ratchets: Strong and weak Parrondo effect

    Science.gov (United States)

    Wu, Degang; Szeto, Kwok Yip

    2014-02-01

    Inspired by the flashing ratchet, Parrondo's game presents an apparently paradoxical situation. Parrondo's game consists of two individual games, game A and game B. Game A is a slightly losing coin-tossing game. Game B has two coins, with an integer parameter M. If the current cumulative capital (in discrete unit) is a multiple of M, an unfavorable coin pb is used, otherwise a favorable pg coin is used. Paradoxically, a combination of game A and game B could lead to a winning game, which is the Parrondo effect. We extend the original Parrondo's game to include the possibility of M being either M1 or M2. Also, we distinguish between strong Parrondo effect, i.e., two losing games combine to form a winning game, and weak Parrondo effect, i.e., two games combine to form a better-performing game. We find that when M2 is not a multiple of M1, the combination of B (M1) and B (M2) has strong and weak Parrondo effect for some subsets in the parameter space (pb,pg), while there is neither strong nor weak effect when M2 is a multiple of M1. Furthermore, when M2 is not a multiple of M1, a stochastic mixture of game A may cancel the strong and weak Parrondo effect. Following a discretization scheme in the literature of Parrondo's game, we establish a link between our extended Parrondo's game with the analysis of discrete Brownian ratchet. We find a relation between the Parrondo effect of our extended model to the macroscopic bias in a discrete ratchet. The slope of a ratchet potential can be mapped to the fair game condition in the extended model, so that under some conditions, the macroscopic bias in a discrete ratchet can provide a good predictor for the game performance of the extended model. On the other hand, our extended model suggests a design of a ratchet in which the potential is a mixture of two periodic potentials.

  2. Strong coupling effects between a meta-atom and MIM nanocavity

    Directory of Open Access Journals (Sweden)

    San Chen

    2012-09-01

    Full Text Available In this paper, we investigate the strong coupling effects between a meta-atom and a metal-insulator-metal (MIM nanocavity. By changing the meta-atom sizes, we achieve the meta-atomic electric dipole, quadrupole or multipole interaction with the plasmonic nanocavity, in which characteristic anticrossing behaviors demonstrate the occurrence of the strong coupling. The various interactions present obviously different splitting values and behaviors of dependence on the meta-atomic position. The largest Rabi-type splittings, about 360.0 meV and 306.1 meV, have been obtained for electric dipole and quadrupole interaction, respectively. We attribute the large splitting to the highly-confined cavity mode and the large transition dipole of the meta-atom. Also the Rabi-type oscillation in time domain is given.

  3. Realization of effective super Tonks-Girardeau gases via strongly attractive one-dimensional Fermi gases

    International Nuclear Information System (INIS)

    Chen Shu; Yin Xiangguo; Guan Liming; Guan Xiwen; Batchelor, M. T.

    2010-01-01

    A significant feature of the one-dimensional super Tonks-Girardeau gas is its metastable gas-like state with a stronger Fermi-like pressure than for free fermions which prevents a collapse of atoms. This naturally suggests a way to search for such strongly correlated behavior in systems of interacting fermions in one dimension. We thus show that the strongly attractive Fermi gas without polarization can be effectively described by a super Tonks-Girardeau gas composed of bosonic Fermi pairs with attractive pair-pair interaction. A natural description of such super Tonks-Girardeau gases is provided by Haldane generalized exclusion statistics. In particular, they are equivalent to ideal particles obeying more exclusive statistics than Fermi-Dirac statistics.

  4. Effects of Strong Correlations on the Disorder-Induced Zero Bias Anomaly

    Science.gov (United States)

    Atkinson, William; Song, Yun; Bulut, Sinan; Wortis, Rachel

    2009-03-01

    In conventional metals and semiconductors, density of states anomalies result from the interplay between disorder and interactions. Motivated by a number of experiments that find zero bias anomalies (ZBA) in transition metal oxides, we have performed calculations to determine the effect of strong correlations on the ZBA in disordered interacting systems. We use a self-consistent mean-field theory that incorporates strong correlations and treats spatial fluctuations of the disorder potential exactly. We discuss both the Anderson-Hubbard model and the extended Anderson-Hubbard model. We find that, even for a zero-range interaction, nonlocal self-energy corrections lead to the formation of an Altshuler-Aronov-like ZBA. In the extended Anderson-Hubbard model, Efros-Shklovskii-like physics dominates at large disorder.

  5. Free Radicals and Extrinsic Skin Aging

    Directory of Open Access Journals (Sweden)

    Borut Poljšak

    2012-01-01

    Full Text Available Human skin is constantly directly exposed to the air, solar radiation, environmental pollutants, or other mechanical and chemical insults, which are capable of inducing the generation of free radicals as well as reactive oxygen species (ROS of our own metabolism. Extrinsic skin damage develops due to several factors: ionizing radiation, severe physical and psychological stress, alcohol intake, poor nutrition, overeating, environmental pollution, and exposure to UV radiation (UVR. It is estimated that among all these environmental factors, UVR contributes up to 80%. UV-induced generation of ROS in the skin develops oxidative stress, when their formation exceeds the antioxidant defence ability of the target cell. The primary mechanism by which UVR initiates molecular responses in human skin is via photochemical generation of ROS mainly formation of superoxide anion (O2−•, hydrogen peroxide (H2O2, hydroxyl radical (OH•, and singlet oxygen (1O2. The only protection of our skin is in its endogenous protection (melanin and enzymatic antioxidants and antioxidants we consume from the food (vitamin A, C, E, etc.. The most important strategy to reduce the risk of sun UVR damage is to avoid the sun exposure and the use of sunscreens. The next step is the use of exogenous antioxidants orally or by topical application and interventions in preventing oxidative stress and in enhanced DNA repair.

  6. Effective action for superfluid Fermi systems in the strong-coupling limit

    International Nuclear Information System (INIS)

    Dupuis, N.

    2005-01-01

    We derive the low-energy effective action for three-dimensional superfluid Fermi systems in the strong-coupling limit, where superfluidity originates from Bose-Einstein condensation of composite bosons. Taking into account density and pairing fluctuations on the same footing, we show that the effective action involves only the fermion density ρ r and its conjugate variable, the phase θ r of the pairing order parameter Δ r . We recover the standard action of a Bose superfluid of density ρ r /2, where the bosons have a mass m B =2m and interact via a repulsive contact potential with amplitude g B =4πa B /m B ,a B =2a (a the s-wave scattering length associated to the fermion-fermion interaction in vacuum). For lattice models, the derivation of the effective action is based on the mapping of the attractive Hubbard model onto the Heisenberg model in a uniform magnetic field, and a coherent state path integral representation of the partition function. The effective description of the Fermi superfluid in the strong-coupling limit is a Bose-Hubbard model with an intersite hopping amplitude t B =J/2 and an on-site repulsive interaction U B =2Jz, where J=4t 2 /U (t and -U are the intersite hopping amplitude and the on-site attraction in the (fermionic) Hubbard model, z the number of nearest-neighbor sites)

  7. Effective action for superfluid Fermi systems in the strong-coupling limit

    Science.gov (United States)

    Dupuis, N.

    2005-07-01

    We derive the low-energy effective action for three-dimensional superfluid Fermi systems in the strong-coupling limit, where superfluidity originates from Bose-Einstein condensation of composite bosons. Taking into account density and pairing fluctuations on the same footing, we show that the effective action involves only the fermion density ρr and its conjugate variable, the phase θr of the pairing order parameter Δr . We recover the standard action of a Bose superfluid of density ρr/2 , where the bosons have a mass mB=2m and interact via a repulsive contact potential with amplitude gB=4πaB/mB,aB=2a ( a the s -wave scattering length associated to the fermion-fermion interaction in vacuum). For lattice models, the derivation of the effective action is based on the mapping of the attractive Hubbard model onto the Heisenberg model in a uniform magnetic field, and a coherent state path integral representation of the partition function. The effective description of the Fermi superfluid in the strong-coupling limit is a Bose-Hubbard model with an intersite hopping amplitude tB=J/2 and an on-site repulsive interaction UB=2Jz , where J=4t2/U ( t and -U are the intersite hopping amplitude and the on-site attraction in the (fermionic) Hubbard model, z the number of nearest-neighbor sites).

  8. Effects of strong radiation reaction and quantum-electrodynamics on relativistic transparency

    Science.gov (United States)

    Zhang, Peng; Thomas, A. G. R.; Ridgers, C. P.

    2013-10-01

    Relativistic transparency is the process that optically switches the overdense plasma from opaque to transparent and enables light propagation through the otherwise opaque plasma, when light of sufficient intensity drives the electrons in the plasma to near light speeds. We study the relativistic transparency in radiation dominant and strong quantum electrodynamic (QED) regime, for the interaction of high-intensity laser pulses with a thin foil solid target. We analytically study the simplified motion of an electron in a circularly polarized plane wave to understand the physics of the transmissivity and absorption in the presence of classical and quantum-corrected, semiclassical radiation-reaction forces and the trapping of particles in nodes of laser standing wave through radiative cooling. These arguments are supported by both one dimensional and two dimensional particle-in-cell calculations including strong field QED effects. Measurement of the transmission of these pulses would be experimentally feasible and a robust test of the strong field QED particle-in-cell framework.

  9. Drag Effect of Kompsat-1 During Strong Solar and Geomagnetic Activity

    Directory of Open Access Journals (Sweden)

    J. Park

    2007-06-01

    Full Text Available In this paper, we analyze the orbital variation of the KOrea Multi-Purpose SATellite-1(KOMPSAT-1 in a strong space environment due to satellite drag by solar and geomagnetic activities. The satellite drag usually occurs slowly, but becomes serious satellite drag when the space environment suddenly changes via strong solar activity like a big flare eruption or coronal mass ejections(CMEs. Especially, KOMPSAT-1 as a low earth orbit satellite has a distinct increase of the drag acceleration by the variations of atmospheric friction. We consider factors of solar activity to have serious effects on the satellite drag from two points of view. One is an effect of high energy radiation when the flare occurs in the Sun. This radiation heats and expands the upper atmosphere of the Earth as the number of neutral particles is suddenly increased. The other is an effect of Joule and precipitating particle heating caused by current of plasma and precipitation of particles during geomagnetic storms by CMEs. It also affects the density of neutral particles by heating the upper atmosphere. We investigate the satellite drag acceleration associated with the two factors for five events selected based on solar and geomagnetic data from 2001 to 2002. The major results can be summarized as follows. First, the drag acceleration started to increase with solar EUV radiation with the best cross-correlation (r = 0.92 for 1 day delayed F10.7. Second, the drag acceleration and Dst index have similar patterns when the geomagnetic storm is dominant and the drag acceleration abruptly increases during the strong geomagnetic storm. Third, the background variation of the drag accelerations is governed by the solar radiation, while their short term (less than a day variations is governed by geomagnetic storms.

  10. Poly-ϵ-caprolactone/chitosan nanoparticles provide strong adjuvant effect for hepatitis B antigen.

    Science.gov (United States)

    Jesus, Sandra; Soares, Edna; Borchard, Gerrit; Borges, Olga

    2017-10-01

    This work aims to investigate the adjuvant effect of poly-ϵ-caprolactone/chitosan nanoparticles (NPs) for hepatitis B surface antigen (HBsAg) and the plasmid DNA encoding HBsAg (pRC/CMV-HBs). Both antigens were adsorbed onto preformed NPs. Vaccination studies were performed in C57BL/6 mice. Transfection efficiency was investigated in A549 cell line. HBsAg-adsorbed NPs generated strong anti-HBsAg IgG titers, mainly of IgG1 isotype, and induced antigen-specific IFN-γ and IL-17 secretion by spleen cells. The addition of pRC/CMV-HBs to the HBsAg-adsorbed NPs inhibited IL-17 secretion but had minor effect on IFN-γ levels. Lastly, pRC/CMV-HBs-loaded NPs generated a weak serum antibody response. Poly-ϵ-caprolactone/chitosan NPs provide a strong humoral adjuvant effect for HBsAg and induce a Th1/Th17-mediated cellular immune responses worth explore for hepatitis B virus vaccination.

  11. Dispersion of Co/CNTs via strong electrostatic adsorption method: Thermal treatment effect

    Energy Technology Data Exchange (ETDEWEB)

    Akbarzadeh, Omid, E-mail: omid.akbarzadeh63@gmail.com; Abdullah, Bawadi, E-mail: bawadi-abdullah@petronas.com.my; Subbarao, Duvvuri, E-mail: duvvuri-subbarao@petronas.com.my [Department of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia); Zabidi, Noor Asmawati Mohd, E-mail: noorasmawati-mzabidi@petronas.com.my [Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2015-07-22

    The effect of different thermal treatment temperature on the structure of multi-walled carbon nanotubes (MWCNTs) and Co particle dispersion on CNTs support is studied using Strong electrostatic adsorption (SEA) method. The samples tested by N{sub 2}-adsorption, field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). N{sub 2}-adsorption results showed BET surface area increased using thermal treatment and TEM images showed that increasing the thermal treatment temperature lead to flaky CNTs and defects introduced on the outer surface and Co particle dispersion increased.

  12. Gain length fitting formula for free-electron lasers with strong space-charge effects

    Directory of Open Access Journals (Sweden)

    G. Marcus

    2011-08-01

    Full Text Available We present a power-fit formula, obtained from a variational analysis using three-dimensional free-electron laser theory, for the gain length of a high-gain free-electron laser’s fundamental mode in the presence of diffraction, uncorrelated energy spread, and longitudinal space-charge effects. The approach is inspired by the work of Xie [Nucl. Instrum. Methods Phys. Res., Sect. A 445, 59 (2000NIMAER0168-900210.1016/S0168-9002(0000114-5], and provides a useful shortcut for calculating the gain length of the fundamental Gaussian mode of a free-electron laser having strong space-charge effects in the 3D regime. The results derived from analytic theory are in good agreement with detailed numerical particle simulations that also include higher-order space-charge effects, supporting the assumptions made in the theoretical treatment and the variational solutions obtained in the single-mode limit.

  13. On the isoperimetric rigidity of extrinsic minimal balls

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, V.

    2003-01-01

    We consider an m-dimensional minimal submanifold P and a metric R-sphere in the Euclidean space R-n. If the sphere has its center p on P, then it will cut out a well defined connected component of P which contains this center point. We call this connected component an extrinsic minimal R-ball of P....... The quotient of the volume of the extrinsic ball and the volume of its boundary is not larger than the corresponding quotient obtained in the space form standard situation, where the minimal submanifold is the totally geodesic linear subspace R-m. Here we show that if the minimal submanifold has dimension...... larger than 3, if P is not too curved along the boundary of an extrinsic minimal R-ball, and if the inequality alluded to above is an equality for the extrinsic minimal ball, then the minimal submanifold is totally geodesic....

  14. CT-semiotics and clinical aspects of extrinsic allergic alveolitis

    International Nuclear Information System (INIS)

    Skrynnikova, I.P.; Momot, N.V.; Vakulenko, I.P.; Tanasichuk-Gazhieva, N.V

    2003-01-01

    Extrinsic allergic alveolitis can be a difficult diagnostic problem. The comparison of the results of CT research with the clinical immunological and morphological data allowed to define the forms and diagnose the characteristic symptoms of the disease

  15. STRONG FIELD EFFECTS ON EMISSION LINE PROFILES: KERR BLACK HOLES AND WARPED ACCRETION DISKS

    International Nuclear Information System (INIS)

    Wang Yan; Li Xiangdong

    2012-01-01

    If an accretion disk around a black hole is illuminated by hard X-rays from non-thermal coronae, fluorescent iron lines will be emitted from the inner region of the accretion disk. The emission line profiles will show a variety of strong field effects, which may be used as a probe of the spin parameter of the black hole and the structure of the accretion disk. In this paper, we generalize the previous relativistic line profile models by including both the black hole spinning effects and the non-axisymmetries of warped accretion disks. Our results show different features from the conventional calculations for either a flat disk around a Kerr black hole or a warped disk around a Schwarzschild black hole by presenting, at the same time, multiple peaks, rather long red tails, and time variations of line profiles with the precession of the disk. We show disk images as seen by a distant observer, which are distorted by the strong gravity. Although we are primarily concerned with the iron K-shell lines in this paper, the calculation is general and is valid for any emission lines produced from a warped accretion disk around a black hole.

  16. Non trivial effect of strong high-frequency excitation on a nonlinear controlled system

    DEFF Research Database (Denmark)

    Fidlin, A.; Thomsen, Jon Juel

    2004-01-01

    due to control is usually high compared to uncontrolled systems. A standard optimal controller for a standard nonlinear system (a movable cart used to balance a pendulum vertically) is shown to exhibit pronounced bias error in presence of HF-excitation. The bias increases with increased excitation......Nontrivial effects of high-frequency excitation on mechanical uncontrolled systems have been investigated intensively in the last decade. Some of these effects are usually used in controlled systems in form of dither to smoothen out undesired friction and hysteresis. However the level of damping...... intensity, but it also increases with the increased control power. Analytic prediction for the bias shows, the interaction between fast excitation and strong damping terms in the control system to be the cause of the permanent control error. A "slow observer" ignoring fast motions is shown...

  17. Trapped in the extinction vortex? Strong genetic effects in a declining vertebrate population

    Directory of Open Access Journals (Sweden)

    Larsson Mikael

    2010-02-01

    Full Text Available Abstract Background Inbreeding and loss of genetic diversity are expected to increase the extinction risk of small populations, but detailed tests in natural populations are scarce. We combine long-term population and fitness data with those from two types of molecular markers to examine the role of genetic effects in a declining metapopulation of southern dunlins Calidris alpina schinzii, an endangered shorebird. Results The decline is associated with increased pairings between related individuals, including close inbreeding (as revealed by both field observations of parentage and molecular markers. Furthermore, reduced genetic diversity seems to affect individual fitness at several life stages. Higher genetic similarity between mates correlates negatively with the pair's hatching success. Moreover, offspring produced by related parents are more homozygous and suffer from increased mortality during embryonic development and possibly also after hatching. Conclusions Our results demonstrate strong genetic effects in a rapidly declining population, emphasizing the importance of genetic factors for the persistence of small populations.

  18. Strong matrix effect in low-energy He+ ion scattering from carbon

    International Nuclear Information System (INIS)

    Mikhailov, S.N.; Van den Oetelaar, L.C.A.; Brongersma, H.H.

    1994-01-01

    In low-energy ion scattering the contribution of neutralization processes to the scattered ion yield is very important in quantification. Neutralization of low-energy (1-3.5 keV) He + ions by carbon is found to be much stronger for graphitic than for carbidic carbon. The ion fraction for graphitic carbon for 2.5 keV 3 He + scattering over 136 is about 60 times lower than that for carbidic carbon. For the 4 He + isotope the effect is even larger. Such a strong matrix effect for one element has not been measured before in low-energy (1-3.5 keV) inert-gas ion scattering. The neutralization behaviour is discussed in terms of a special quasi-resonant neutralization process for graphite. ((orig.))

  19. Strongly correlated Fermi-systems: Non-Fermi liquid behavior, quasiparticle effective mass and their interplay

    Energy Technology Data Exchange (ETDEWEB)

    Shaginyan, V.R. [Petersburg Nuclear Physics Institute, RAS, Gatchina 188300 (Russian Federation); Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel)], E-mail: vrshag@thd.pnpi.spb.ru; Amusia, M.Ya. [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); Popov, K.G. [Komi Science Center, Ural Division, RAS, Syktyvkar 167982 (Russian Federation)

    2009-06-15

    Basing on the density functional theory of fermion condensation, we analyze the non-Fermi liquid behavior of strongly correlated Fermi-systems such as heavy-fermion metals. When deriving equations for the effective mass of quasiparticles, we consider solids with a lattice and homogeneous systems. We show that the low-temperature thermodynamic and transport properties are formed by quasiparticles, while the dependence of the effective mass on temperature, number density, magnetic fields, etc., gives rise to the non-Fermi liquid behavior. Our theoretical study of the heat capacity, magnetization, energy scales, the longitudinal magnetoresistance and magnetic entropy are in good agreement with the remarkable recent facts collected on the heavy-fermion metal YbRh{sub 2}Si{sub 2}.

  20. Strongly correlated Fermi-systems: Non-Fermi liquid behavior, quasiparticle effective mass and their interplay

    International Nuclear Information System (INIS)

    Shaginyan, V.R.; Amusia, M.Ya.; Popov, K.G.

    2009-01-01

    Basing on the density functional theory of fermion condensation, we analyze the non-Fermi liquid behavior of strongly correlated Fermi-systems such as heavy-fermion metals. When deriving equations for the effective mass of quasiparticles, we consider solids with a lattice and homogeneous systems. We show that the low-temperature thermodynamic and transport properties are formed by quasiparticles, while the dependence of the effective mass on temperature, number density, magnetic fields, etc., gives rise to the non-Fermi liquid behavior. Our theoretical study of the heat capacity, magnetization, energy scales, the longitudinal magnetoresistance and magnetic entropy are in good agreement with the remarkable recent facts collected on the heavy-fermion metal YbRh 2 Si 2 .

  1. Bactericidal Effect of Strong Acid Electrolyzed Water against Flow Enterococcus faecalis Biofilms.

    Science.gov (United States)

    Cheng, Xiaogang; Tian, Yu; Zhao, Chunmiao; Qu, Tiejun; Ma, Chi; Liu, Xiaohua; Yu, Qing

    2016-07-01

    This study evaluated the bactericidal effect of strong acid electrolyzed water (SAEW) against flow Enterococcus faecalis biofilm and its potential application as a root canal irrigant. Flow E. faecalis biofilms were generated under a constant shear flow in a microfluidic system. For comparison, static E. faecalis biofilms were generated under a static condition on coverslip surfaces. Both the flow and static E. faecalis biofilms were treated with SAEW. Sodium hypochlorite (NaOCl, 5.25%) and normal saline (0.9%) were included as the controls. Bacterial reductions were evaluated using confocal laser scanning microscopy and the cell count method. Morphological changes of bacterial cells were observed using scanning electron microscopy. The confocal laser scanning microscopic and cell count results showed that SAEW had a bactericidal effect similar to that of 5.25% NaOCl against both the flow and static E. faecalis biofilms. The scanning electron microscopic results showed that smooth, consecutive, and bright bacteria surfaces became rough, shrunken, and even lysed after treated with SAEW, similar to those in the NaOCl group. SAEW had an effective bactericidal effect against both the flow and static E. faecalis biofilms, and it might be qualified as a root canal irrigant for effective root canal disinfection. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. Long-term effects of the strong African American families program on youths' alcohol use.

    Science.gov (United States)

    Brody, Gene H; Chen, Yi-Fu; Kogan, Steven M; Murry, Velma McBride; Brown, Anita C

    2010-04-01

    This report extends earlier accounts by addressing the effects of the Strong African American Families (SAAF) program across 65 months. Two hypotheses were tested: (a) Rural African American youths randomly assigned to participate in SAAF would demonstrate lower rates of alcohol use than would control youths more than 5 years later, and (b) SAAF's effects on deterring the onset of alcohol use in early adolescence would carry forward to mediate the program's long-term effects. African American youths in rural Georgia (mean age at pretest = 10.8 years) were assigned randomly to the SAAF group (n = 369) or to a control group (n = 298). Past-month alcohol use was assessed at pretest and at 9, 18, 29, 53, and 65 months after pretest. SAAF participants increased their alcohol use at a slower rate than did adolescents in the control condition across the follow-up assessments. At the 65-month assessment, SAAF participants reported having drunk alcohol half as often as did youths in the control group. Consistent with the second hypothesis, SAAF's effects on deterring initiation carried forward to account for its effects on alcohol use across time. Training in protective parenting processes and self-regulatory skills during preadolescence may contribute to a self-sustaining trajectory of disinterest in and avoidance of alcohol use during adolescence when peers begin to model and sanction it. (c) 2010 APA, all rights reserved

  3. Fitness is strongly influenced by rare mutations of large effect in a microbial mutation accumulation experiment.

    Science.gov (United States)

    Heilbron, Karl; Toll-Riera, Macarena; Kojadinovic, Mila; MacLean, R Craig

    2014-07-01

    Our understanding of the evolutionary consequences of mutation relies heavily on estimates of the rate and fitness effect of spontaneous mutations generated by mutation accumulation (MA) experiments. We performed a classic MA experiment in which frequent sampling of MA lines was combined with whole genome resequencing to develop a high-resolution picture of the effect of spontaneous mutations in a hypermutator (ΔmutS) strain of the bacterium Pseudomonas aeruginosa. After ∼644 generations of mutation accumulation, MA lines had accumulated an average of 118 mutations, and we found that average fitness across all lines decayed linearly over time. Detailed analyses of the dynamics of fitness change in individual lines revealed that a large fraction of the total decay in fitness (42.3%) was attributable to the fixation of rare, highly deleterious mutations (comprising only 0.5% of fixed mutations). Furthermore, we found that at least 0.64% of mutations were beneficial and probably fixed due to positive selection. The majority of mutations that fixed (82.4%) were base substitutions and we failed to find any signatures of selection on nonsynonymous or intergenic mutations. Short indels made up a much smaller fraction of the mutations that were fixed (17.4%), but we found evidence of strong selection against indels that caused frameshift mutations in coding regions. These results help to quantify the amount of natural selection present in microbial MA experiments and demonstrate that changes in fitness are strongly influenced by rare mutations of large effect. Copyright © 2014 by the Genetics Society of America.

  4. Strong isotope effects on melting dynamics and ice crystallisation processes in cryo vitrification solutions.

    Directory of Open Access Journals (Sweden)

    Oleg Kirichek

    Full Text Available The nucleation and growth of crystalline ice during cooling, and further crystallization processes during re-warming are considered to be key processes determining the success of low temperature storage of biological objects, as used in medical, agricultural and nature conservation applications. To avoid these problems a method, termed vitrification, is being developed to inhibit ice formation by use of high concentration of cryoprotectants and ultra-rapid cooling, but this is only successful across a limited number of biological objects and in small volume applications. This study explores physical processes of ice crystal formation in a model cryoprotective solution used previously in trials on vitrification of complex biological systems, to improve our understanding of the process and identify limiting biophysical factors. Here we present results of neutron scattering experiments which show that even if ice crystal formation has been suppressed during quench cooling, the water molecules, mobilised during warming, can crystallise as detectable ice. The crystallisation happens right after melting of the glass phase formed during quench cooling, whilst the sample is still transiting deep cryogenic temperatures. We also observe strong water isotope effects on ice crystallisation processes in the cryoprotectant mixture. In the neutron scattering experiment with a fully protiated water component, we observe ready crystallisation occurring just after the glass melting transition. On the contrary with a fully deuteriated water component, the process of crystallisation is either completely or substantially supressed. This behaviour might be explained by nuclear quantum effects in water. The strong isotope effect, observed here, may play an important role in development of new cryopreservation strategies.

  5. Effect of Floodplain Inundation on River Pollution in Taiwan's Strong Monsoonal Climate

    Science.gov (United States)

    Hester, E. T.; Lin, A. Y. C.

    2017-12-01

    River-floodplain interaction provides important benefits such as flood mitigation, provision of ecological habitat, and improved water quality. Human actions have historically reduced such interaction and associated benefits by diking, floodplain fill, and river regulation. In response, floodplain restoration has become popular in North America and Europe, but is less practiced in Asia. In Taiwan, unusually strong monsoons and steep terrain alter floodplain dynamics relative to elsewhere around the world, and provide a unique environment for floodplain management. We used numerical models of flow, transport, and reaction in river channels and floodplains to quantify the effect of river-floodplain interaction on water quality in Taiwan's strong monsoon and high topographic relief. We conducted sensitivity analyses of parameters such as river slope, monsoon severity, reservoir operation mode, degree of floodplain reconnection, contaminant reaction rate, and contaminant reaction type on floodplain connectivity and contaminant mitigation. We found significant differences in floodplain hydraulics and residence times in Taiwan's steep monsoonal environment relative to the shallower non-monsoonal environment typical of the eastern USA, with significant implications for water quality. For example, greater flashiness of floodplain inundation in Taiwan provides greater challenges for reconnecting sufficient floodplain volume to handle monsoonal runoff. Yet longer periods when floodplains are reliably dry means that such lands may have greater value for seasonal use such as parks or agriculture. The potential for floodplain restoration in Taiwan is thus significant, but qualitatively different than in the eastern USA.

  6. Mental health care and average happiness: strong effect in developed nations.

    Science.gov (United States)

    Touburg, Giorgio; Veenhoven, Ruut

    2015-07-01

    Mental disorder is a main cause of unhappiness in modern society and investment in mental health care is therefore likely to add to average happiness. This prediction was checked in a comparison of 143 nations around 2005. Absolute investment in mental health care was measured using the per capita number of psychiatrists and psychologists working in mental health care. Relative investment was measured using the share of mental health care in the total health budget. Average happiness in nations was measured with responses to survey questions about life-satisfaction. Average happiness appeared to be higher in countries that invest more in mental health care, both absolutely and relative to investment in somatic medicine. A data split by level of development shows that this difference exists only among developed nations. Among these nations the link between mental health care and happiness is quite strong, both in an absolute sense and compared to other known societal determinants of happiness. The correlation between happiness and share of mental health care in the total health budget is twice as strong as the correlation between happiness and size of the health budget. A causal effect is likely, but cannot be proved in this cross-sectional analysis.

  7. Biodiversity effects in the wild are common and as strong as key drivers of productivity

    Science.gov (United States)

    Duffy, J. Emmett; Godwin, Casey M.; Cardinale, Bradley J.

    2017-09-01

    More than 500 controlled experiments have collectively suggested that biodiversity loss reduces ecosystem productivity and stability. Yet the importance of biodiversity in sustaining the world’s ecosystems remains controversial, largely because of the lack of validation in nature, where strong abiotic forcing and complex interactions are assumed to swamp biodiversity effects. Here we test this assumption by analysing 133 estimates reported in 67 field studies that statistically separated the effects of biodiversity on biomass production from those of abiotic forcing. Contrary to the prevailing opinion of the previous two decades that biodiversity would have rare or weak effects in nature, we show that biomass production increases with species richness in a wide range of wild taxa and ecosystems. In fact, after controlling for environmental covariates, increases in biomass with biodiversity are stronger in nature than has previously been documented in experiments and comparable to or stronger than the effects of other well-known drivers of productivity, including climate and nutrient availability. These results are consistent with the collective experimental evidence that species richness increases community biomass production, and suggest that the role of biodiversity in maintaining productive ecosystems should figure prominently in global change science and policy.

  8. Biodiversity effects in the wild are common and as strong as key drivers of productivity.

    Science.gov (United States)

    Duffy, J Emmett; Godwin, Casey M; Cardinale, Bradley J

    2017-09-14

    More than 500 controlled experiments have collectively suggested that biodiversity loss reduces ecosystem productivity and stability. Yet the importance of biodiversity in sustaining the world's ecosystems remains controversial, largely because of the lack of validation in nature, where strong abiotic forcing and complex interactions are assumed to swamp biodiversity effects. Here we test this assumption by analysing 133 estimates reported in 67 field studies that statistically separated the effects of biodiversity on biomass production from those of abiotic forcing. Contrary to the prevailing opinion of the previous two decades that biodiversity would have rare or weak effects in nature, we show that biomass production increases with species richness in a wide range of wild taxa and ecosystems. In fact, after controlling for environmental covariates, increases in biomass with biodiversity are stronger in nature than has previously been documented in experiments and comparable to or stronger than the effects of other well-known drivers of productivity, including climate and nutrient availability. These results are consistent with the collective experimental evidence that species richness increases community biomass production, and suggest that the role of biodiversity in maintaining productive ecosystems should figure prominently in global change science and policy.

  9. The strong specific effect of coions on micellar growth from molecular-thermodynamic theory.

    Science.gov (United States)

    Koroleva, S V; Victorov, A I

    2014-09-07

    Viscoelastic solutions of ionic surfactants with an added salt exhibit a surprisingly strong dependence of their behavior on the nature of the added coion. We apply a recently proposed molecular-thermodynamic model to elucidate the effect of a coion's specificity on the aggregation of cationic and anionic surfactants. We show that micellar growth and branching are opposed by penetration of coions inside a micelle's corona leading to an increase of the aggregate's preferential curvature. These effects result from hydration/dehydration and dispersion attraction of coions and are only important at high salinity where electrostatic repulsion of coions from the micelle is screened and where branching of micelles and viscosity maxima are observed. At low and medium salinity, the coion plays a minor role; its effect on critical micelle concentration and sphere-to-rod transitions is insignificant. Our molecular-thermodynamic approach describes the specific effects of both counterions and coions and their different roles at different salinity levels based on a unified physical picture.

  10. Room temperature strong coupling effects from single ZnO nanowire microcavity

    KAUST Repository

    Das, Ayan

    2012-05-01

    Strong coupling effects in a dielectric microcavity with a single ZnO nanowire embedded in it have been investigated at room temperature. A large Rabi splitting of ?100 meV is obtained from the polariton dispersion and a non-linearity in the polariton emission characteristics is observed at room temperature with a low threshold of 1.63 ?J/cm2, which corresponds to a polariton density an order of magnitude smaller than that for the Mott transition. The momentum distribution of the lower polaritons shows evidence of dynamic condensation and the absence of a relaxation bottleneck. The polariton relaxation dynamics were investigated by timeresolved measurements, which showed a progressive decrease in the polariton relaxation time with increase in polariton density. © 2012 Optical Society of America.

  11. Global dynamics and bifurcation analysis of a host-parasitoid model with strong Allee effect.

    Science.gov (United States)

    Khan, Abdul Qadeer; Ma, Jiying; Xiao, Dongmei

    2017-12-01

    In this paper, we study the global dynamics and bifurcations of a two-dimensional discrete time host-parasitoid model with strong Allee effect. The existence of fixed points and their stability are analysed in all allowed parametric region. The bifurcation analysis shows that the model can undergo fold bifurcation and Neimark-Sacker bifurcation. As the parameters vary in a small neighbourhood of the Neimark-Sacker bifurcation condition, the unique positive fixed point changes its stability and an invariant closed circle bifurcates from the positive fixed point. From the viewpoint of biology, the invariant closed curve corresponds to the periodic or quasi-periodic oscillations between host and parasitoid populations. Furthermore, it is proved that all solutions of this model are bounded, and there exist some values of the parameters such that the model has a global attractor. These theoretical results reveal the complex dynamics of the present model.

  12. Strong-field effects in Rabi oscillations between a single state and a superposition of states

    International Nuclear Information System (INIS)

    Zhdanovich, S.; Milner, V.; Hepburn, J. W.

    2011-01-01

    Rabi oscillations of quantum population are known to occur in two-level systems driven by spectrally narrow laser fields. In this work we study Rabi oscillations induced by shaped broadband femtosecond laser pulses. Due to the broad spectral width of the driving field, the oscillations are initiated between a ground state and a coherent superposition of excited states, or a ''wave packet,'' rather than a single excited state. Our experiments reveal an intricate dependence of the wave-packet phase on the intensity of the laser field. We confirm numerically that the effect is associated with the strong-field nature of the interaction and provide a qualitative picture by invoking a simple theoretical model.

  13. Channel-closing effects in strong-field ionization by a bicircular field

    Science.gov (United States)

    Milošević, D. B.; Becker, W.

    2018-03-01

    Channel-closing effects, such as threshold anomalies and resonantlike intensity-dependent enhancements in strong-field ionization by a bicircular laser field are analyzed. A bicircular field consists of two coplanar corotating or counter-rotating circularly polarized fields having different frequencies. For the total detachment rate of a negative ion by a bicircular field we observe threshold anomalies and explain them using the Wigner threshold law and energy and angular momentum conservation. For the corotating bicircular case, these effects are negligible, while for the counter-rotating case they are pronounced and their position depends on the magnetic quantum number of the initial state. For high-order above-threshold ionization of rare-gas atoms by a counter-rotating bicircular laser field we observe very pronounced intensity-dependent enhancements. We find all four types of threshold anomalies known from collision theory. Contrary to the case of linear polarization, channel-closing effects for a bicircular field are visible also in the cutoff region of the electron energy spectrum, which is explained using quantum-orbit theory.

  14. Strong quantum-confined stark effect in germanium quantum-well structures on silicon

    International Nuclear Information System (INIS)

    Kuo, Y.; Lee, Y. K.; Gei, Y.; Ren, S; Roth, J. E.; Miller, D. A.; Harris, J. S.

    2006-01-01

    Silicon is the dominant semiconductor for electronics, but there is now a growing need to integrate such component with optoelectronics for telecommunications and computer interconnections. Silicon-based optical modulators have recently been successfully demonstrated but because the light modulation mechanisms in silicon are relatively weak, long (for example, several millimeters) devices or sophisticated high-quality-factor resonators have been necessary. Thin quantum-well structures made from III-V semiconductors such as GaAs, InP and their alloys exhibit the much stronger Quantum-Confined Stark Effect (QCSE) mechanism, which allows modulator structures with only micrometers of optical path length. Such III-V materials are unfortunately difficult to integrate with silicon electronic devices. Germanium is routinely integrated with silicon in electronics, but previous silicon-germanium structures have also not shown strong modulation effects. Here we report the discovery of the QCSE, at room temperature, in thin germanium quantum-well structures grown on silicon. The QCSE here has strengths comparable to that in III-V materials. Its clarity and strength are particularly surprising because germanium is an indirect gap semiconductor, such semiconductors often display much weak optical effects than direct gap materials (such as the III-V materials typically used for optoelectronics). This discovery is very promising for small, high-speed, low-power optical output devices fully compatible with silicon electronics manufacture. (author)

  15. Strong mechanically induced effects in DC current-biased suspended Josephson junctions

    Science.gov (United States)

    McDermott, Thomas; Deng, Hai-Yao; Isacsson, Andreas; Mariani, Eros

    2018-01-01

    Superconductivity is a result of quantum coherence at macroscopic scales. Two superconductors separated by a metallic or insulating weak link exhibit the AC Josephson effect: the conversion of a DC voltage bias into an AC supercurrent. This current may be used to activate mechanical oscillations in a suspended weak link. As the DC-voltage bias condition is remarkably difficult to achieve in experiments, here we analyze theoretically how the Josephson effect can be exploited to activate and detect mechanical oscillations in the experimentally relevant condition with purely DC current bias. We unveil how changing the strength of the electromechanical coupling results in two qualitatively different regimes showing dramatic effects of the oscillations on the DC-voltage characteristic of the device. These include the appearance of Shapiro-type plateaus for weak coupling and a sudden mechanically induced retrapping for strong coupling. Our predictions, measurable in state-of-the-art experimental setups, allow the determination of the frequency and quality factor of the resonator using DC only techniques.

  16. Intrinsic and extrinsic motivation in early adolescents' friendship development: friendship selection, influence, and prospective friendship quality.

    Science.gov (United States)

    Ojanen, Tiina; Sijtsema, Jelle J; Hawley, Patricia H; Little, Todd D

    2010-12-01

    Friendships are essential for adolescent social development. However, they may be pursued for varying motives, which, in turn, may predict similarity in friendships via social selection or social influence processes, and likely help to explain friendship quality. We examined the effect of early adolescents' (N = 374, 12-14 years) intrinsic and extrinsic friendship motivation on friendship selection and social influence by utilizing social network modeling. In addition, longitudinal relations among motivation and friendship quality were estimated with structural equation modeling. Extrinsic motivation predicted activity in making friendship nominations during the sixth grade and lower friendship quality across time. Intrinsic motivation predicted inactivity in making friendship nominations during the sixth, popularity as a friend across the transition to middle school, and higher friendship quality across time. Social influence effects were observed for both motives, but were more pronounced for intrinsic motivation. Copyright © 2010 The Association for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  17. Biological effects of electromagnetic fields and recently updated safety guidelines for strong static magnetic fields

    International Nuclear Information System (INIS)

    Yamaguchi-Sekino, Sachiko; Sekino, Masaki; Ueno, Shoogo

    2011-01-01

    Humans are exposed daily to artificial and naturally occurring magnetic fields that originate from many different sources. We review recent studies that examine the biological effects of and medical applications involving electromagnetic fields, review the properties of static and pulsed electromagnetic fields that affect biological systems, describe the use of a pulsed electromagnetic field in combination with an anticancer agent as an example of a medical application that incorporates an electromagnetic field, and discuss the recently updated safety guidelines for static electromagnetic fields. The most notable modifications to the 2009 International Commission on Non-Ionizing Radiation Protection guidelines are the increased exposure limits, especially for those who work with or near electromagnetic fields (occupational exposure limits). The recommended increases in exposure were determined using recent scientific evidence obtained from animal and human studies. Several studies since the 1994 publication of the guidelines have examined the effects on humans after exposure to high static electromagnetic fields (up to 9.4 tesla), but additional research is needed to ascertain further the safety of strong electromagnetic fields. (author)

  18. Biological effects of electromagnetic fields and recently updated safety guidelines for strong static magnetic fields.

    Science.gov (United States)

    Yamaguchi-Sekino, Sachiko; Sekino, Masaki; Ueno, Shoogo

    2011-01-01

    Humans are exposed daily to artificial and naturally occurring magnetic fields that originate from many different sources. We review recent studies that examine the biological effects of and medical applications involving electromagnetic fields, review the properties of static and pulsed electromagnetic fields that affect biological systems, describe the use of a pulsed electromagnetic field in combination with an anticancer agent as an example of a medical application that incorporates an electromagnetic field, and discuss the recently updated safety guidelines for static electromagnetic fields. The most notable modifications to the 2009 International Commission on Non-Ionizing Radiation Protection guidelines are the increased exposure limits, especially for those who work with or near electromagnetic fields (occupational exposure limits). The recommended increases in exposure were determined using recent scientific evidence obtained from animal and human studies. Several studies since the 1994 publication of the guidelines have examined the effects on humans after exposure to high static electromagnetic fields (up to 9.4 tesla), but additional research is needed to ascertain further the safety of strong electromagnetic fields.

  19. Effect of horizontal strong static magnetic field on swimming behaviour of Paramecium caudatum

    Science.gov (United States)

    Fujiwara, Yoshihisa; Tomishige, Masahiko; Itoh, Yasuhiro; Fujiwara, Masao; Shibata, Naho; Kosaka, Toshikazu; Hosoya, Hiroshi; Tanimoto, Yoshifumi

    2006-05-01

    Effect of horizontal strong static magnetic field on swimming behaviour of Paramecium caudatum was studied by using a superconducting magnet. Around a centre of a round vessel, random swimming at 0 T and aligned swimming parallel to the magnetic field (MF) of 8 T were observed. Near a wall of the vessel, however, swimming round and round along the wall at 0 T and aligned swimming of turning at right angles upon collision with the wall, which was remarkable around 1-4 T, were detected. It was experimentally revealed that the former MF-induced parallel swimming at the vessel centre was caused physicochemically by the parallel magnetic orientation of the cell itself. From magnetic field dependence of the extent of the orientation, the magnetic susceptibility anisotropy (χ ∥-χ ⊥) was first obtained to be 3.4× 10-23 emu cell-1 at 298 K for Paramecium caudatum. The orientation of the cell was considered to result from the magnetic orientation of the cell membrane. On the other hand, although mechanisms of the latter swimming near the vessel wall regardless of the absence and presence of the magnetic field are unclear at present, these experimental results indicate that whether the cell exists near the wall alters the magnetic field effect on the swimming in the horizontal magnetic field.

  20. Detailed site effect estimation in the presence of strong velocity reversals within a small-aperture strong-motion array in Iceland

    KAUST Repository

    Rahpeyma, Sahar

    2016-08-11

    The rock site characterization for earthquake engineering applications in Iceland is common due to the easily exposed older bedrock and more recent volcanic lava rock. The corresponding site amplification is generally assumed to be low but has not been comprehensively quantified, especially for volcanic rock. The earthquake strong-motion of the Mw6.3 Ölfus earthquake on 29 May 2008 and 1705 of its aftershocks recorded on the first small-aperture strong-motion array (ICEARRAY I) in Iceland showed consistent and significant variations in ground motion amplitudes over short distances (<2 km) in an urban area located mostly on lava rock. This study analyses the aftershock recordings to quantify the local site effects using the Horizontal to Vertical Spectral Ratio (HVSR) and Standard Spectral Ratio (SSR) methods. Additionally, microseismic data has been collected at array stations and analyzed using the HVSR method. The results between the methods are consistent and show that while the amplification levels remain relatively low, the predominant frequency varies systematically between stations and is found to correlate with the geological units. In particular, for stations on lava rock the underlying geologic structure is characterized by repeated lava-soil stratigraphy characterized by reversals in the shear wave velocity with depth. As a result, standard modeling of HVSR using vertically incident body waves does not apply. Instead, modeling the soil structure as a two-degree-of-freedom dynamic system is found to capture the observed predominant frequencies of site amplification. The results have important implications for earthquake resistant design of structures on rock sites characterized by velocity reversals. © 2016 Elsevier Ltd

  1. Effective potential in the strong-coupling lattice QCD with next-to-next-to-learning order effects

    International Nuclear Information System (INIS)

    Nakano, Takashi Z.; Miura, Kohtaroh; Ohnishi, Akira

    2010-01-01

    We derive an analytic expression of the effective potential at finite temperature (T) and chemical potential (μ) in the strong-coupling lattice QCD for color SU(3) including next-to-next-to-leading order (NNLO) effects in the strong coupling expansion. NNLO effective action terms are systematically evaluated in the leading order of the large dimensional (1/d) expansion, and are found to come from some types of connected two-plaquette configurations. We apply the extended Hubbard-Stratonovich transformation and a gluonic-dressed fermion technique to the effective action, and obtain the effective potential as a function of T, μ, and two order parameters: chiral condensate and vector potential field. The next-to-leading order (NLO) and NNLO effects result in modifications of the wave function renormalization factor, quark mass, and chemical potential. We find that T c,μ =0 and μ c,T =0 are similar to the NLO results, whereas the position of the critical point is sensitive to NNLO corrections. (author)

  2. Examining the relationship between recreational sport participation and intrinsic and extrinsic motivation and amotivation.

    Science.gov (United States)

    Tsorbatzoudis, Haralambos; Alexandris, Konstantinos; Zahariadis, Panagiotis; Grouios, George

    2006-10-01

    This study aimed at investigating the effect of motivational dimensions proposed by Pelletier, et al. in 1995, both on sport participation levels and on intention for continuing participation among adult recreational sport participants. Two hundred and fifty-seven adult individuals, who reported participation in some type of sport and physical activity, completed the Sport Motivation Scale and a scale measuring intention. The study provided evidence to suggest that increased motivation leads to increased participation. Amotivation significantly decreased from the least to the most frequent participant groups, while both extrinsic and intrinsic motivation followed the reverse pattern. The results also indicated that increased intrinsic motivation to gain knowledge and accomplishment and extrinsic motivation (introjected regulation) are positively correlated with individuals' intentions to continue participation, while amotivation is negatively related. These results provide limited support for the self-determination theory. Implications for sport participation promotion are discussed.

  3. Intrinsic and extrinsic motivation for stereotypic and repetitive behavior.

    Science.gov (United States)

    Joosten, Annette V; Bundy, Anita C; Einfeld, Stewart L

    2009-03-01

    This study provides evidence for intrinsic and extrinsic motivators for stereotypical and repetitive behavior in children with autism and intellectual disability and children with intellectual disability alone. We modified the Motivation Assessment Scale (MAS) (1988b); dividing it into intrinsic and extrinsic measures and adding items to assess anxiety as an intrinsic motivator. Rasch analysis of data from 279 MASs (74 children) revealed that the items formed two unidimensional scales. Anxiety was a more likely intrinsic motivator than sensory seeking for children with dual diagnoses; the reverse was true for children with intellectual disability only. Escape and gaining a tangible object were the most common extrinsic motivators for those with dual diagnoses and attention and escape for children with intellectual disability.

  4. Extrinsic Motivation Index: A New Tool for Managing Labor Productivity

    Directory of Open Access Journals (Sweden)

    Berumen, S.A.

    2016-07-01

    Full Text Available The objective of this paper is to provide a tool of practical significance for HR managers and firm executives. This tool, which is called Extrinsic Motivation Index (EMI, is meant to measure the extrinsic motivation of employees. By measuring employees' extrinsic motivation, managers are able to track job satisfaction and, subsequently, implement measures aiming both to raise job satisfaction and to improve organizational commitment. In order to test the validity of the model, we apply the EMI to Faculty members at Spanish and German universities. We also carry out simulation experiments in order to to address all possible situations an organization most probably will have to deal with. The results point out significant differences in the level of motivation and commitment of Faculty members. Additionally, the analysis shows several ways in which an organization may manage job satisfaction issues according to on its level of resources.

  5. Disorder effects on helical edge transport in graphene under a strong tilted magnetic field

    Science.gov (United States)

    Huang, Chunli; Cazalilla, Miguel A.

    2015-10-01

    In a recent experiment, Young et al. [Nature (London) 505, 528 (2014), 10.1038/nature12800] observed a metal to insulator transition as well as transport through helical edge states in monolayer graphene under a strong, tilted magnetic field. Under such conditions, the bulk is a magnetic insulator which can exhibit metallic conduction through helical edges. It was found that the two-terminal conductance of the helical channels deviates from the expected quantized value (=e2/h per edge, at zero temperature). Motivated by this observation, we study the effect of disorder on the conduction through the edge channels. We show that, unlike for helical edges of topological insulators in semiconducting quantum wells, a disorder Rashba spin-orbit coupling does not lead to backscattering, at least to leading order. Instead, we find that the lack of perfect antialignment of the electron spins in the helical channels to be the most likely cause for backscattering arising from scalar (i.e., spin-independent) impurities. The intrinsic spin-orbit coupling and other time-reversal symmetry-breaking and/or sublattice parity-breaking potentials also lead to (subleading) corrections to the channel conductance.

  6. Effect of dipole polarizability on positron binding by strongly polar molecules

    International Nuclear Information System (INIS)

    Gribakin, G F; Swann, A R

    2015-01-01

    A model for positron binding to polar molecules is considered by combining the dipole potential outside the molecule with a strongly repulsive core of a given radius. Using existing experimental data on binding energies leads to unphysically small core radii for all of the molecules studied. This suggests that electron–positron correlations neglected in the simple model play a large role in determining the binding energy. We account for these by including the polarization potential via perturbation theory and non-perturbatively. The perturbative model makes reliable predictions of binding energies for a range of polar organic molecules and hydrogen cyanide. The model also agrees with the linear dependence of the binding energies on the polarizability inferred from the experimental data (Danielson et al 2009 J. Phys. B: At. Mol. Opt. Phys. 42 235203). The effective core radii, however, remain unphysically small for most molecules. Treating molecular polarization non-perturbatively leads to physically meaningful core radii for all of the molecules studied and enables even more accurate predictions of binding energies to be made for nearly all of the molecules considered. (paper)

  7. Strong gravity effects of rotating black holes: quasi-periodic oscillations

    International Nuclear Information System (INIS)

    Aliev, Alikram N; Esmer, Göksel Daylan; Talazan, Pamir

    2013-01-01

    We explore strong gravity effects of the geodesic motion in the spacetime of rotating black holes in general relativity and braneworld gravity. We focus on the description of the motion in terms of three fundamental frequencies: the orbital frequency, the radial and vertical epicyclic frequencies. For a Kerr black hole, we perform a detailed numerical analysis of these frequencies at the innermost stable circular orbits and beyond them as well as at the characteristic stable orbits, at which the radial epicyclic frequency attains its highest value. We find that the values of the epicyclic frequencies for a class of stable orbits exhibit good qualitative agreement with the observed frequencies of the twin peaks quasi-periodic oscillations (QPOs) in some black hole binaries. We also find that at the characteristic stable circular orbits, where the radial (or the vertical) epicyclic frequency has maxima, the vertical and radial epicyclic frequencies exhibit an approximate 2:1 ratio even in the case of near-extreme rotation of the black hole. Next, we perform a similar analysis of the fundamental frequencies for a rotating braneworld black hole and argue that the existence of such a black hole with a negative tidal charge, whose angular momentum exceeds the Kerr bound in general relativity, does not confront with the observations of high-frequency QPOs. (paper)

  8. Peak ground motions, effective duration of strong motions and frequency content of Iranian earthquakes

    International Nuclear Information System (INIS)

    Tehranizadeh, M.; Hamedi, F.

    2002-01-01

    The characteristics of earthquake ground motion have great influences on the response of structures to the earthquakes. Peak ground motions, duration of strong motions and frequency content are important characteristics of earthquakes, which are studied in this paper. The relation between peak ground acceleration, velocity and displacement have been taken into account and the effects of magnitude, epicentral distance and recorded duration of earthquakes on peak ground acceleration have been presented as graphs. The frequency content of ground motion can be examined by power spectral density of accel ero grams. In this study the power spectral density of the records have been determined and normalized power spectral densities are compared. There are different formulas for the smoothed power spectral density function such as Kanai-Tajimi's model. In this study, comparing with Kanai-Tajim's formula, the extreme value model is suggested for the spectral density function. This model is evaluated for accel ero grams on different soil conditions and the smoothed mean power spectral density function are determined for each soil groups. The central frequency and predominant period of earthquakes are also estimated

  9. Exploring Intrinsic and Extrinsic Motivations to Participate in a Crowdsourcing Project to Support Blind and Partially Sighted Students.

    Science.gov (United States)

    Layas, Fatma; Petrie, Helen

    2016-01-01

    There have been a number of crowdsourcing projects to support people with disabilities. However, there is little exploration of what motivates people to participate in such crowdsourcing projects. In this study we investigated how different motivational factors can affect the participation of people in a crowdsourcing project to support visually disabled students. We are developing "DescribeIT", a crowdsourcing project to support blind and partially students by having sighted people describe images in digital learning resources. We investigated participants' behavior of the DescribeIT project using three conditions: one intrinsic motivation condition and two extrinsic motivation conditions. The results showed that participants were significantly intrinsically motivated to participate in the DescribeIT project. In addition, participants' intrinsic motivation dominated the effect of the two extrinsic motivational factors in the extrinsic conditions.

  10. Strong mutagenic effects of diesel engine emissions using vegetable oil as fuel.

    Science.gov (United States)

    Bünger, Jürgen; Krahl, Jürgen; Munack, Axel; Ruschel, Yvonne; Schröder, Olaf; Emmert, Birgit; Westphal, Götz; Müller, Michael; Hallier, Ernst; Brüning, Thomas

    2007-08-01

    Diesel engine emissions (DEE) are classified as probably carcinogenic to humans. In recent years every effort was made to reduce DEE and their content of carcinogenic and mutagenic polycyclic aromatic compounds. Since 1995 we observed an appreciable reduction of mutagenicity of DEE driven by reformulated or newly designed fuels in several studies. Recently, the use of rapeseed oil as fuel for diesel engines is rapidly growing among German transportation businesses and agriculture due to economic reasons. We compared the mutagenic effects of DEE from two different batches of rapeseed oil (RSO) with rapeseed methyl ester (RME, biodiesel), natural gas derived synthetic fuel (gas-to-liquid, GTL), and a reference diesel fuel (DF). The test engine was a heavy-duty truck diesel running the European Stationary Cycle. Particulate matter from the exhaust was sampled onto PTFE-coated glass fibre filters and extracted with dichloromethane in a soxhlet apparatus. The gas phase constituents were sampled as condensates. The mutagenicity of the particle extracts and the condensates was tested using the Salmonella typhimurium/mammalian microsome assay with tester strains TA98 and TA100. Compared to DF the two RSO qualities significantly increased the mutagenic effects of the particle extracts by factors of 9.7 up to 59 in tester strain TA98 and of 5.4 up to 22.3 in tester strain TA100, respectively. The condensates of the RSO fuels caused an up to factor 13.5 stronger mutagenicity than the reference fuel. RME extracts had a moderate but significant higher mutagenic response in assays of TA98 with metabolic activation and TA100 without metabolic activation. GTL samples did not differ significantly from DF. In conclusion, the strong increase of mutagenicity using RSO as diesel fuel compared to the reference DF and other fuels causes deep concern on future usage of this biologic resource as a replacement of established diesel fuels.

  11. Autler-Townes effect in a strongly driven electromagnetically induced transparency resonance

    International Nuclear Information System (INIS)

    Yang Lijun; Zhang Lianshui; Li Xiaoli; Han Li; Fu Guangsheng; Manson, Neil B.; Suter, Dieter; Wei Changjiang

    2005-01-01

    In this paper we study the nonlinear behavior of an electromagnetically induced transparency (EIT) resonance subject to a coherent driving field. The EIT is associated with a Λ three-level system where two hyperfine levels within an electronic ground state are coupled to a common excited state level by a coupling field and a probe field. In addition there is an radio-frequency (rf) field driving a hyperfine transition within the ground state. The paper contrasts two different situations. In one case the rf-driven transition shares a common level with the probed transition and in the second case it shares a common level with the coupled transition. In both cases the EIT resonance is split into a doublet and the characteristics of the EIT doublet are determined by the strength and frequency of the rf-driving field. The doublet splitting originates from the rf-field induced dynamic Stark effect and has close analogy with the Autler-Townes effect observed in three-level pump-probe spectroscopy study. The situation changes when the rf field is strong and the two cases are very different. One is analogous to two Λ three-level systems with EIT resonance associated with each. The other corresponds to a doubly driven three-level system with rf-field-induced electromagnetically induced absorption resonance. The two situations are modeled using numerical solutions of the relevant equation of motion of density matrix. In addition a physical account of their behaviors is given in terms of a dressed state picture

  12. Effects of the Coulomb potential in interference patterns of strong-field holography with photoelectrons

    Science.gov (United States)

    Shvetsov-Shilovski, N. I.; Lein, M.

    2018-01-01

    Using the semiclassical two-step model for strong-field ionization we investigate the interference structures emerging in strong-field photoelectron holography, taking into account the Coulomb potential of the atomic core. For every kind of the interference pattern predicted by the three-step model, we calculate the corresponding structure in the presence of the Coulomb field, showing that the Coulomb potential modifies the interference patterns significantly.

  13. Modeling consequences of prolonged strong unpredictable stress in zebrafish: Complex effects on behavior and physiology.

    Science.gov (United States)

    Song, Cai; Liu, Bai-Ping; Zhang, Yong-Ping; Peng, Zhilan; Wang, JiaJia; Collier, Adam D; Echevarria, David J; Savelieva, Katerina V; Lawrence, Robert F; Rex, Christopher S; Meshalkina, Darya A; Kalueff, Allan V

    2018-02-02

    Chronic stress is the major pathogenetic factor of human anxiety and depression. Zebrafish (Danio rerio) have become a novel popular model species for neuroscience research and CNS drug discovery. The utility of zebrafish for mimicking human affective disorders is also rapidly growing. Here, we present a new zebrafish model of clinically relevant, prolonged unpredictable strong chronic stress (PUCS). The 5-week PUCS induced overt anxiety-like and motor retardation-like behaviors in adult zebrafish, also elevating whole-body cortisol and proinflammatory cytokines - interleukins IL-1β and IL-6. PUCS also elevated whole-body levels of the anti-inflammatory cytokine IL-10 and increased the density of dendritic spines in zebrafish telencephalic neurons. Chronic treatment of fish with an antidepressant fluoxetine (0.1mg/L for 8days) normalized their behavioral and endocrine phenotypes, as well as corrected stress-elevated IL-1β and IL-6 levels, similar to clinical and rodent data. The CNS expression of the bdnf gene, the two genes of its receptors (trkB, p75), and the gfap gene of glia biomarker, the glial fibrillary acidic protein, was unaltered in all three groups. However, PUCS elevated whole-body BDNF levels and the telencephalic dendritic spine density (which were corrected by fluoxetine), thereby somewhat differing from the effects of chronic stress in rodents. Together, these findings support zebrafish as a useful in-vivo model of chronic stress, also calling for further cross-species studies of both shared/overlapping and distinct neurobiological responses to chronic stress. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Effects of strong bite force on the facial vertical dimension of pembarong performers

    Directory of Open Access Journals (Sweden)

    C. Christina

    2017-06-01

    Full Text Available Background: A pembarong performer is a reog dancer who bites on a piece of wood inserted into his/her mouth in order to support a 60 kg Barongan or Dadak Merak mask. The teeth supporting this large and heavy mask are directly affected, as the strong bite force exerted during a dance could affect their vertical and sagital facial dimensions. Purpose: This study aimed to examine the influence of the bite force of pembarong performers due to their vertical and sagital facial dimensions. Methods: The study reported here involved fifteen pembarong performers and thirteen individuals with normal occlusion (with specific criteria. The bite force of these subjects was measured with a dental prescale sensor during its centric occlusion. A cephalometric variation measurement was subsequently performed on all subjects with its effects on their vertical and sagital facial dimensions being measured. Results: The bite force value of the pembarong performers was 394.3816 ± 7.68787 Newtons, while the normal occlusion was 371.7784 ± 4.77791 Newtons. There was no correlation between the bite force and the facial sagital dimension of these subjects. However, a significant correlation did exist between bite force and lower facial height/total facial height (LFH/TFH ratio (p = 0.013. Conversely, no significant correlation between bite force and posterior facial height/total facial height (PFH/TFH ratio (p = 0.785 was detected. There was an inverse correlation between bite force and LFH/TFH ratio (r = -.464. Conclusion: Bite force is directly related to the decrease in LFH/TFH ratio. Occlusal pressure exerted by the posterior teeth on the alveolar bone may increase bone density at the endosteal surface of cortical bone.

  15. Strong and nonlinear effects of fragmentation on ecosystem service provision at multiple scales

    Science.gov (United States)

    Mitchell, Matthew G. E.; Bennett, Elena M.; Gonzalez, Andrew

    2015-09-01

    Human actions, such as converting natural land cover to agricultural or urban land, result in the loss and fragmentation of natural habitat, with important consequences for the provision of ecosystem services. Such habitat loss is especially important for services that are supplied by fragments of natural land cover and that depend on flows of organisms, matter, or people across the landscape to produce benefits, such as pollination, pest regulation, recreation and cultural services. However, our quantitative knowledge about precisely how different patterns of landscape fragmentation might affect the provision of these types of services is limited. We used a simple, spatially explicit model to evaluate the potential impact of natural land cover loss and fragmentation on the provision of hypothetical ecosystem services. Based on current literature, we assumed that fragments of natural land cover provide ecosystem services to the area surrounding them in a distance-dependent manner such that ecosystem service flow depended on proximity to fragments. We modeled seven different patterns of natural land cover loss across landscapes that varied in the overall level of landscape fragmentation. Our model predicts that natural land cover loss will have strong and unimodal effects on ecosystem service provision, with clear thresholds indicating rapid loss of service provision beyond critical levels of natural land cover loss. It also predicts the presence of a tradeoff between maximizing ecosystem service provision and conserving natural land cover, and a mismatch between ecosystem service provision at landscape versus finer spatial scales. Importantly, the pattern of landscape fragmentation mitigated or intensified these tradeoffs and mismatches. Our model suggests that managing patterns of natural land cover loss and fragmentation could help influence the provision of multiple ecosystem services and manage tradeoffs and synergies between services across different human

  16. Extrinsic photoresponse enhancement under additional intrinsic photoexcitation in organic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Kounavis, P., E-mail: pkounavis@upatras.gr [Department of Electrical and Computer Engineering, School of Engineering, University of Patras, 26504 Patras (Greece)

    2016-06-28

    Dual light beam photoresponse experiments are employed to explore the photoresponse under simultaneous extrinsic and intrinsic photoexcitation of organic semiconductors. The photoresponse of a red modulated light extrinsic photoexcitation is found that can be significantly enhanced under an additional blue bias-light intrinsic photoexcitation in two terminal pentacene films on glass substrates. From the frequency resolved photoresponse, it is deduced that the phenomenon of photoresponse enhancement can be attributed to an increase in the extrinsic photogeneration rate of the red modulated light and/or an improvement of the drift velocity of carriers under an additional blue light intrinsic photoexcitation. The possible predominant extrinsic photogeneration mechanism, which can be compatible with the observed dependence of the photoresponse enhancement on the frequency and on the light intensities of the red and blue light excitation, is the singlet exciton dissociation through electron transfer to acceptor-like traps. Moreover, an improvement in the drift velocity of carriers traversing grain boundaries with potential energy barriers, which may be reduced by trapping of minority carriers created from the intrinsic photoexcitation, may partly contribute to the photoresponse enhancement.

  17. Extrinsic motivation and job satisfaction of teachers' in public post ...

    African Journals Online (AJOL)

    Extrinsic motivation and job satisfaction of teachers' in public post primary schools in Cross River State, Nigeria. ... grossly dissatisfied and uncommitted to their jobs. It was recommended that government should improve the salary of teachers, promote them regularly and make policies that will ensure their job security.

  18. Impact of Mentoring on Perceived Adequacy of Extrinsic ...

    African Journals Online (AJOL)

    This study examined the impact of informal mentoring on perceived adequacy of extrinsic organizational rewards such as pay, promotion and fringe benefit. Data were obtained from 161 employees through a survey of a public health organisation in south-western Nigeria. Hierarchical regression analysis revealed that ...

  19. Distinct molecular signatures of mild extrinsic and intrinsic atopic dermatitis

    DEFF Research Database (Denmark)

    Martel, Britta Cathrina; Litman, Thomas; Hald, Andreas

    2016-01-01

    Atopic dermatitis (AD) is a common inflammatory skin disease with underlying defects in epidermal function and immune responses. In this study, we used microarray analysis to investigate differences in gene expression in lesional skin from patients with mild extrinsic or intrinsic AD compared...

  20. The Impact of Extrinsic Demographic Factors on Cantonese Speech Acquisition

    Science.gov (United States)

    To, Carol K. S.; Cheung, Pamela S. P.; McLeod, Sharynne

    2013-01-01

    This study modeled the associations between extrinsic demographic factors and children's speech acquisition in Hong Kong Cantonese. The speech of 937 Cantonese-speaking children aged 2;4 to 6;7 in Hong Kong was assessed using a standardized speech test. Demographic information regarding household income, paternal education, maternal education,…

  1. extrinsic factors that affect employee job satisfaction in faith based ...

    African Journals Online (AJOL)

    The general objective of this study was to identify the extrinsic factors affect employee job satisfaction at the Faith based organizations. For the research methodology, the study used the descriptive research design. The population for the study was the 161 employees of the Nairobi Chapel. Stratified random sampling ...

  2. Modelling of Extrinsic Fiber Optic Sagnac Ultrasound Interferometer ...

    African Journals Online (AJOL)

    Ultrasonic waves are used extensively in nondestructive testing both for characterization of material properties, in this paper, we describe a fiber optic sensor suitable for detection of ultrasonic waves. This sensor is based on an extrinsic fiber optic sagnac interferometer. The proposed sensor model can act as a conventional ...

  3. Observation of strong magnetic effects in visible-infrared sum frequency generation from magnetic structures

    NARCIS (Netherlands)

    Kirilyuk, A.; Knippels, G.M.H.; van der Meer, A. F. G.; Renard, S.; Rasing, T.; Heskamp, I. R.; Lodder, J. C.

    2000-01-01

    We have observed very strong magnetization-induced changes of the infrared-visible sum-frequency generation (SFG) intensity from thin magnetic films using a free electron laser as a tunable infrared source. With the help of a magnetic grating a clear resonance is observed due to the excitation of

  4. Flavor changing strong interaction effects on top quark physics at the CERN LHC

    International Nuclear Information System (INIS)

    Ferreira, P.M.; Santos, R.; Oliveira, O.

    2006-01-01

    We perform a model independent analysis of the flavor changing strong interaction vertices relevant to the LHC. In particular, the contribution of dimension six operators to single top production in various production processes is discussed, together with possible hints for identifying signals and setting bounds on physics beyond the standard model

  5. The effect of packaging, branding and labeling on the experience of unhealthy food and drink: A review.

    Science.gov (United States)

    Skaczkowski, Gemma; Durkin, Sarah; Kashima, Yoshihisa; Wakefield, Melanie

    2016-04-01

    Extrinsic information, such as packaging, branding and labeling, can significantly alter our experience of food and drink through a process of 'sensation transfer', in which extrinsic attributes are transferred to our sensory perception of a product. The aim of this review was to summarize the literature on sensation transfer for unhealthy food and drink and to investigate personal factors that may influence its occurrence. Seventy-eight studies in 69 articles, published between 1966 and 2014 were identified which evaluated sensation transfer. Sixty-five of the 78 studies found an effect of extrinsic information on taste and/or hedonic outcomes, providing strong evidence for sensation transfer. The majority of studies identified that specific extrinsic information influenced particular products or specific sensory outcomes. Study designs incorporating a measure of expectation allowed a tighter assessment of sensation transfer. The results of such studies confirm the hypothesis that these effects occur when extrinsic information elicits an expectation of product taste, which then forms a framework to guide sensory perception. These studies also support the hypothesis that where sensation transfer does not occur, this is likely due to a mismatch between the expectations elicited by the extrinsic information and the sensory characteristics being measured, or the failure of the extrinsic information to elicit an expectation of taste for that product. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability

    NARCIS (Netherlands)

    Frielink, N.; Schuengel, C.; Embregts, P.J.C.M.

    Background According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and

  7. Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability

    NARCIS (Netherlands)

    Frielink, N.; Schuengel, C.; Embregts, P.J.C.M.

    2017-01-01

    Background: According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and

  8. Interference effects at photoionization of Rydberg atoms by a strong electromagnetic field

    International Nuclear Information System (INIS)

    Movsesyan, A.M.; Fedorov, M.V.

    1989-01-01

    The photoionization of Rydberg atoms in a strong electromagnetic field is considered. Degeneration of the levels with respect to the orbital moment, their Stark splitting and the possibility of resonant interaction with levels of lower energy are taken into account. The complex quasi-energies of the system, photoelectron spectrum in the limit of an infinite duration of interaction and the time dependence of the total ionization probability are found. It is shown that a narrowing of the quasi-energy levels occurs in a strong field. Against a background of the quasi- continuum the quasi-energy spectrum consists of more or less narrow levels. In this case the photoelectron spectrum acquires a multi-peak form. With increasing field strength the height of the peaks increases, whereas their width decreases. The ionization rate decreases with increasing field strength. The presence of a quasi-continuum is the cause of the partially non-exponential nature of the atomic disintegration

  9. Carrier envelope phase effects in molecular dissociation by few-cycle strong laser fields

    Energy Technology Data Exchange (ETDEWEB)

    Dimitriou, K I [Hellenic Army Academy, Department of Natural Science and Applications, Vari (Greece); Constantoudis, V [Institute of Microelectronics, NCSR ' Demokritos' , Athens (Greece); Mercouris, Th [Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, Athens (Greece); Nicolaides, C A, E-mail: dimi@eie.g [Physics Department, National Technical University, Athens (Greece)

    2009-11-01

    Multiphoton molecular dissociation produced by few-cycle strong laser fields of mid-infrared wave lengths is studied theoretically. The dependence of the carrier envelope phase (CEP) on the photodissociation dynamics is investigated using both quantum and classical nonperturbative approaches. Our results show that dissociation is affected by the changes of the CEP. A detailed analysis shows that this dependence is sensitive to the duration and to the shape of the pulse.

  10. Effects of strong cathodic polarization of the Ni-YSZ interface

    DEFF Research Database (Denmark)

    Hansen, Karin Vels; Chen, Ming; Jacobsen, Torben

    2016-01-01

    Long-term strong cathodic polarization experiments of down to -2.4 V vs. E°(O2) of the Ni-YSZ interface were performed at 900°C in 97% H2/3% H2O on model electrodes. The Ni-YSZ interface underwent extensive changes and a large affected volume with a complex microstructure and phase distribution r...

  11. Extrinsic versus Intrinsic Motivation in Faculty Development.

    Science.gov (United States)

    Sloan, E. Dendy

    1989-01-01

    Discusses the motivation of faculty for effective teaching. Describes five stages in faculty growth and development. Suggests some implications of career phases and motivational studies. Lists 22 references. (YP)

  12. Effect of a strong, DC-induced magnetic field on circadian singing activity of the house cricket (orthoptera:gryllidae)

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, K.C.; Bitzer, R.J.; Galliart, L. [Iowa State Univ., Ames, IA (United States)] [and others

    1995-05-01

    We investigated the effect of a strong, DC-induced electromagnetic field (EMF) on the circadian singing activity of the house cricket, Acheta domesticus (L.). Groups of 10 crickets were exposed to strong, DC-induced EMFs under two light regimes, 12:12 (L:D) h and 0:24 (L:D) h. Exposure to the strong EMF resulted in an increase in mean time per hour during which one or more crickets were singing and in number of crickets singing per hour. Correcting for phase shift during O:24 (L:D) h, the daily pattern of singing was apparently unaffected by any treatment. The greatest percentage of singing and number of crickets singing per hour occurred during actual or expected scotophase. This is the first report of an increase in insect activity during exposure to a strong DC-induced EMF.

  13. Engagement in Classroom Learning: Creating Temporal Participation Incentives for Extrinsically Motivated Students through Bonus Credits

    Science.gov (United States)

    Rassuli, Ali

    2012-01-01

    Extrinsic inducements to adjust students' learning motivations have evolved within 2 opposing paradigms. Cognitive evaluation theories claim that controlling factors embedded in extrinsic rewards dissipate intrinsic aspirations. Behavioral theorists contend that if engagement is voluntary, extrinsic reinforcements enhance learning without ill…

  14. The effect of regional variation of seismic wave attenuation on the strong ground motion from earthquakes

    International Nuclear Information System (INIS)

    Chung, D.H.; Bernreuter, D.L.

    1981-10-01

    Attenuation is caused by geometric spreading and absorption. Geometric spreading is almost independent of crustal geology and physiographic region, but absorption depends strongly on crustal geology and the state of the earth's upper mantle. Except for very high frequency waves, absorption does not affect ground motion at distances less than about 25 to 50 km. Thus, in the near-field zone, the attenuation in the eastern United States is similar to that in the western United States. Beyond the near field, differences in ground motion can best be accounted for by differences in attenuation caused by differences in absorption. The stress drop of eastern earthquakes may be higher than for western earthquakes of the same seismic moment, which would affect the high-frequency spectral content. But we believe this factor is of much less significance than differences in absorption in explaining the differences in ground motion between the East and the West. The characteristics of strong ground motion in the conterminous United States are discussed in light of these considerations, and estimates are made of the epicentral ground motions in the central and eastern United States. (author)

  15. Involvement of the Extrinsic and Intrinsic Pathways in Ultraviolet B-Induced Apoptosis of Corneal Epithelial Cells

    Science.gov (United States)

    Ubels, John L.; Glupker, Courtney D.; Schotanus, Mark P.; Haarsma, Loren D.

    2015-01-01

    The goal of this study was to elucidate the pathway by which UVB initiates efflux of K+ and subsequently apoptosis in human corneal limbal epithelial (HCLE) cells. The initial focus of the study was on the extrinsic pathway involving Fas. HCLE cells transfected with Fas siRNA were exposed to 80–150 mJ/cm2 UVB and incubated in culture medium with 5.5 mM K+. Knock down of Fas resulted in limited reduction in UVB-induced caspase-8 and -3 activity. Patch-clamp recordings showed no difference in UVB-induced normalized K+ currents between Fas transfected and control cells. Knockdown of caspase-8 had no effect on the activation of caspase-3 following UVB exposure, while a caspase-8 inhibitor completely eliminated UVB activation of caspase-3. This suggests that caspase-8 is a robust enzyme, able to activate caspase-3 via residual caspase-8 present after knockdown, and that caspase-8 is directly involved in the UVB activation of caspase-3. Inhibition of caspase-9 significantly decreased the activation of caspases-8 and -3 in response to UVB. Knockdown of Apaf-1, required for activation of caspase-9, resulted in a significant reduction in UVB-induced activation of caspases-9, -8, and -3. Knockdown of Apaf-1 also inhibited intrinsic and UVB-induced levels of apoptosis, as determined by DNA fragmentation measured by TUNEL assay. In UVB exposed cultures treated with caspase-3 inhibitor, the percentage of apoptotic cells was reduced to control levels, confirming the necessity of caspase-3 activation in DNA fragmentation. The lack of effect of Fas knockdown on K+ channel activation, as well as the limited effect on activation of caspases-8 and -3, strongly suggest that Fas and the extrinsic pathway is not of primary importance in the initiation of apoptosis in response to UVB in HCLE cells. Inhibition of caspase-8 and -3 activation following inhibition of caspase-9, as well as reduction in activation of caspases-9, -8, and -3 and DNA fragmentation in response to Apaf-1

  16. Resolution of strong singularities and geodesic completeness in loop quantum Bianchi-II spacetimes

    Science.gov (United States)

    Saini, Sahil; Singh, Parampreet

    2017-12-01

    Generic resolution of singularities and geodesic completeness in the loop quantization of Bianchi-II spacetimes with arbitrary minimally coupled matter is investigated. Using the effective Hamiltonian approach, we examine two available quantizations: one based on the connection operator and second by treating extrinsic curvature as connection via gauge fixing. It turns out that for the connection based quantization, either the inverse triad modifications or imposition of weak energy condition is necessary to obtain a resolution of all strong singularities and geodesic completeness. In contrast, the extrinsic curvature based quantization generically resolves all strong curvature singularities and results in a geodesically complete effective spacetime without inverse triad modifications or energy conditions. In both the quantizations, weak curvature singularities can occur resulting from divergences in pressure and its derivatives at finite densities. These are harmless events beyond which geodesics can be extended. Our work generalizes previous results on the generic resolution of strong singularities in the loop quantization of isotropic, Bianchi-I and Kantowski–Sachs spacetimes.

  17. Near-UV laser treatment of extrinsic dental enamel stains.

    Science.gov (United States)

    Schoenly, J E; Seka, W; Featherstone, J D B; Rechmann, P

    2012-04-01

    The selective ablation of extrinsic dental enamel stains using a 400-nm laser is evaluated at several fluences for completely removing stains with minimal damage to the underlying enamel. A frequency-doubled Ti:sapphire laser (400-nm wavelength, 60-nanosecond pulse duration, 10-Hz repetition rate) was used to treat 10 extracted human teeth with extrinsic enamel staining. Each tooth was irradiated perpendicular to the surface in a back-and-forth motion over a 1-mm length using an ∼300-µm-diam 10th-order super-Gaussian beam with fluences ranging from 0.8 to 6.4 J/cm(2) . Laser triangulation determined stain depth and volume removed by measuring 3D surface images before and after irradiation. Scanning electron microscopy evaluated the surface roughness of enamel following stain removal. Fluorescence spectroscopy measured spectra of unbleached and photobleached stains in the spectral range of 600-800 nm. Extrinsic enamel stains are removed with laser fluences between 0.8 and 6.4 J/cm(2) . Stains removed on sound enamel leave behind a smooth enamel surface. Stain removal in areas with signs of earlier cariogenic acid attacks resulted in isolated and randomly located laser-induced, 50-µm-diam enamel pits. These pits contain 0.5-µm diam, smooth craters indicative of heat transfer from the stain to the enamel and subsequent melting and water droplet ejection. Ablation stalling of enamel stains is typically observed at low fluences (<3 J/cm(2) ) and is accompanied by a drastic reduction in porphyrin fluorescence from the Soret band. Laser ablation of extrinsic enamel stains at 400 nm is observed to be most efficient above 3 J/cm(2) with minimal damage to the underlying enamel. Unsound underlying enamel is also observed to be selectively removed after irradiation. Copyright © 2012 Wiley Periodicals, Inc.

  18. arXiv Strong reduction of the effective radiation length in an oriented PWO scintillator crystal

    CERN Document Server

    Bandiera, L.; Romagnoni, M.; Argiolas, N.; Bagli, E.; Ballerini, G.; Berra, A.; Brizzolani, C.; Camattari, R.; De Salvador, D.; Haurylavets, V.; Mascagna, V.; Mazzolari, A.; Prest, M.; Soldani, M.; Sytov, A.; Vallazza, E.

    We measured a considerable increase of the emitted radiation by 120 GeV/c electrons in an axially oriented lead tungstate scintillator crystal, if compared to the case in which the sample was not aligned with the beam direction. This enhancement resulted from the interaction of particles with the strong crystalline field. The data collected at the external lines of CERN SPS were critically compared to Monte Carlo simulations based on the Baier Katkov quasiclassical method, highlighting a reduction of the scintillator radiation length by a factor of five in case of beam alignment with the [001] crystal axes. As a consequence, oriented scintillator crystals may be profitably exploited to reduce the amount of material in electromagnetic calorimeters/detectors for fixed-target experiments in high-energy physics, as well as for satellite-borne gamma-telescopes in astrophysics.

  19. Effects of weak and strong localization in tunnel characteristics of contacts on HTSC base

    International Nuclear Information System (INIS)

    Revenko, Yu.V.; Svistunov, V.M.; Grigut', O.V.; Belogolovskij, M.A.; Khachaturov, A.I.

    1992-01-01

    It is found that a phenomena governed by the electronic processes in the disordered surface normal layer of material are observed in the tunnel contatcs bases on metal oxide superconductors of 1-2-3 group. Measured characteristics σ(U)=dI/dU ore determined both by contact's barrier properties and conductivity in the disordered region of metal oxides in the vicinity of a barrier. As regards high-temperature contacts σ(U) value at high temperatures us determined by the Schottky barrier and at low temperatures - by activation processes of charge transfer over strongly localized states in near-the-barrier region of the contact. Crossing over towards logarithmic dependence in the tunnel conductuvity σ(U) of low-Ohmic transitions are attributed to the occurrence of 2D state density conditions in the tunnel surface layers of metal oxides

  20. Mechanisms of rotator cuff tendinopathy: intrinsic, extrinsic, or both?

    Science.gov (United States)

    Seitz, Amee L; McClure, Philip W; Finucane, Sheryl; Boardman, N Douglas; Michener, Lori A

    2011-01-01

    The etiology of rotator cuff tendinopathy is multi-factorial, and has been attributed to both extrinsic and intrinsic mechanisms. Extrinsic factors that encroach upon the subacromial space and contribute to bursal side compression of the rotator cuff tendons include anatomical variants of the acromion, alterations in scapular or humeral kinematics, postural abnormalities, rotator cuff and scapular muscle performance deficits, and decreased extensibility of pectoralis minor or posterior shoulder. A unique extrinsic mechanism, internal impingement, is attributed to compression of the posterior articular surface of the tendons between the humeral head and glenoid and is not related to subacromial space narrowing. Intrinsic factors that contribute to rotator cuff tendon degradation with tensile/shear overload include alterations in biology, mechanical properties, morphology, and vascularity. The varied nature of these mechanisms indicates that rotator cuff tendinopathy is not a homogenous entity, and thus may require different treatment interventions. Treatment aimed at addressing mechanistic factors appears to be beneficial for patients with rotator cuff tendinopathy, however, not for all patients. Classification of rotator cuff tendinopathy into subgroups based on underlying mechanism may improve treatment outcomes. 2010 Elsevier Ltd. All rights reserved.

  1. Stochastic synchronization of neuronal populations with intrinsic and extrinsic noise.

    KAUST Repository

    Bressloff, Paul C

    2011-05-03

    We extend the theory of noise-induced phase synchronization to the case of a neural master equation describing the stochastic dynamics of an ensemble of uncoupled neuronal population oscillators with intrinsic and extrinsic noise. The master equation formulation of stochastic neurodynamics represents the state of each population by the number of currently active neurons, and the state transitions are chosen so that deterministic Wilson-Cowan rate equations are recovered in the mean-field limit. We apply phase reduction and averaging methods to a corresponding Langevin approximation of the master equation in order to determine how intrinsic noise disrupts synchronization of the population oscillators driven by a common extrinsic noise source. We illustrate our analysis by considering one of the simplest networks known to generate limit cycle oscillations at the population level, namely, a pair of mutually coupled excitatory (E) and inhibitory (I) subpopulations. We show how the combination of intrinsic independent noise and extrinsic common noise can lead to clustering of the population oscillators due to the multiplicative nature of both noise sources under the Langevin approximation. Finally, we show how a similar analysis can be carried out for another simple population model that exhibits limit cycle oscillations in the deterministic limit, namely, a recurrent excitatory network with synaptic depression; inclusion of synaptic depression into the neural master equation now generates a stochastic hybrid system.

  2. Strong control and squeezing effects of radiation states in a slab waveguide sandwiched between two omnidirectional mirrors

    NARCIS (Netherlands)

    van Driel, H.M.; Hoekstra, Hugo; Stoffer, Remco; Yudistira, D.

    The effect of sandwiching a slab waveguide in air between two omnidirectional mirrors on the local density of modes is investigated theoretically. Design aspects of such a structure are considered, and it is shown that the local density of modes other than the slab-guided mode can be strongly

  3. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition.

    Science.gov (United States)

    Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

    2016-01-01

    Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

  4. Survey of strong motion earthquake effects on thermal power plants in California with emphasis on piping systems. Volume 2, Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, J.D. [Stevenson and Associates, Cleveland, OH (United States)

    1995-11-01

    Volume 2 of the ``Survey of Strong Motion Earthquake Effects on Thermal Power Plants in California with Emphasis on Piping Systems`` contains Appendices which detail the detail design and seismic response of several power plants subjected to strong motion earthquakes. The particular plants considered include the Ormond Beach, Long Beach and Seal Beach, Burbank, El Centro, Glendale, Humboldt Bay, Kem Valley, Pasadena and Valley power plants. Included is a typical power plant piping specification and photographs of typical power plant piping specification and photographs of typical piping and support installations for the plants surveyed. Detailed piping support spacing data are also included.

  5. Photogeneration of neutrino and axions under stimulating effect of strong magnetic field

    CERN Document Server

    Skobelev, V V

    2001-01-01

    The processes of the neutrino and axions photoproduction on the gamma(Ze) -> gamma(nu nu-bar), gamma alpha nuclei, as well as the photon inelastic scattering on the gamma gamma -> gamma(nu nu-bar), gamma alpha photon are considered within the frames of the developed two-dimensional co-variant theory for calculating the matrix of the Feynman diagrams in the strong magnetic field. The contribution of the neutrino radiative photoproduction on the nuclei to the luminosity of the magnetic neutron stars on the early stages of their evolution may compete with the URCA-processes, because the matrix elements in the four-pole diagram depend linearly on the induction of B magnetic field by the B values approx 10 sup 3 -10 sup 4 B sub 0 (B sub 0 = m sub e sup 2 /|e| = 4.41 x 10 sup 1 sup 3 Gs). The evaluation of the axion mass upper boundary, compatible with other independent results, is obtained from the condition of the neutrino luminosity prevailing over the axion one at supposed temperature and magnetic field inducti...

  6. Transgenerational effects of mild heat in Arabidopsis thaliana show strong genotype specificity that is explained by climate at origin.

    Science.gov (United States)

    Groot, Maartje P; Kubisch, Alexander; Ouborg, N Joop; Pagel, Jörn; Schmid, Karl J; Vergeer, Philippine; Lampei, Christian

    2017-08-01

    Transgenerational environmental effects can trigger strong phenotypic variation. However, it is unclear how cues from different preceding generations interact. Also, little is known about the genetic variation for these life history traits. Here, we present the effects of grandparental and parental mild heat, and their combination, on four traits of the third-generation phenotype of 14 Arabidopsis thaliana genotypes. We tested for correlations of these effects with climate and constructed a conceptual model to identify the environmental conditions that favour the parental effect on flowering time. We observed strong evidence for genotype-specific transgenerational effects. On average, A. thaliana accustomed to mild heat produced more seeds after two generations. Parental effects overruled grandparental effects in all traits except reproductive biomass. Flowering was generally accelerated by all transgenerational effects. Notably, the parental effect triggered earliest flowering in genotypes adapted to dry summers. Accordingly, this parental effect was favoured in the model when early summer heat terminated the growing season and environments were correlated across generations. Our results suggest that A. thaliana can partly accustom to mild heat over two generations and genotype-specific parental effects show non-random evolutionary divergence across populations that may support climate change adaptation in the Mediterranean. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  7. The effect of whole body irradiation on the action of strong analgesics of mice

    International Nuclear Information System (INIS)

    Cvetkovicj, M.; Milovanovicj, A.; Tanasijevicj, D.

    1987-01-01

    The effect of whole body irradiation of male mice with single doses of 3 and 7 Gy ( 60 Co source) on analgesic action of three morphine-like drugs was studied. Over the first 6 days after irradiation, the analgesic effect of alfentanil and fentanyl was significantly less pronounced in irradiated animals than in control ones. During the subsequent period of 24 days till the end of experiment, the analgesic effect in irradiated animals gradually increased reaching and exceeding the control values. On the contrary, the analgesic effect of butorphanole was less pronounced in irradiated animals than in control ones, although the difference was not significantly. The difference between butorphanole and other two drugs are probably due to chemical structure and the metabolic fate in the body. (author) 8 refs.; 2 figs

  8. Color and context: an ERP study on intrinsic and extrinsic feature binding in episodic memory.

    Science.gov (United States)

    Ecker, Ullrich K H; Zimmer, Hubert D; Groh-Bordin, Christian

    2007-09-01

    Episodic memory for intrinsic item and extrinsic context information is postulated to rely on two distinct types of representation: object and episodic tokens. These provide the basis for familiarity and recollection, respectively. Electrophysiological indices of these processes (ERP old-new effects) were used together with behavioral data to test these assumptions. We manipulated an intrinsic object feature (color; Experiment 1) and a contextual feature (background; Experiments 1 and 2). In an inclusion task (Experiment 1), the study-test manipulation of color affected object recognition performance and modulated ERP old-new effects associated with both familiarity and recollection. In contrast, a contextual manipulation had no effect, although both intrinsic and extrinsic information was available in a direct feature (source memory) test. When made task relevant (exclusion task; Experiment 2), however, context affected the ERP recollection effect, while still leaving the ERP familiarity effect uninfluenced. We conclude that intrinsic features bound in object tokens are involuntarily processed during object recognition, thus influencing familiarity, whereas context features bound in episodic tokens are voluntarily accessed, exclusively influencing recollection. Figures depicting all the electrodes analyzed are available in an online supplement at www.psychonomic.org/archive.

  9. Strong-field ionization of xenon dimers: The effect of two-equivalent-center interference and of driving ionic transitions

    Science.gov (United States)

    Zhang, C.; Feng, T.; Raabe, N.; Rottke, H.

    2018-02-01

    Strong-field ionization (SFI) of the homonuclear noble gas dimer Xe2 is investigated and compared with SFI of the Xe atom and of the ArXe heteronuclear dimer by using ultrashort Ti:sapphire laser pulses and photoelectron momentum spectroscopy. The large separation of the two nuclei of the dimer allows the study of two-equivalent-center interference effects on the photoelectron momentum distribution. Comparing the experimental results with a new model calculation, which is based on the strong-field approximation, actually reveals the influence of interference. Moreover, the comparison indicates that the presence of closely spaced gerade and ungerade electronic state pairs of the Xe2 + ion at the Xe2 ionization threshold, which are strongly dipole coupled, affects the photoelectron momentum distribution.

  10. Impact of the strong electromagnetic field on the QCD effective potential for homogeneous Abelian gluon field configurations

    International Nuclear Information System (INIS)

    Galilo, Bogdan V.; Nedelko, Sergei N.

    2011-01-01

    The one-loop quark contribution to the QCD effective potential for the homogeneous Abelian gluon field in the presence of an external strong electromagnetic field is evaluated. The structure of extrema of the potential as a function of the angles between chromoelectric, chromomagnetic, and electromagnetic fields is analyzed. In this setup, the electromagnetic field is considered as an external one while the gluon field represents domain structured nonperturbative gluon configurations related to the QCD vacuum in the confinement phase. Two particularly interesting gluon configurations, (anti-)self-dual and crossed orthogonal chromomagnetic and chromoelectric fields, are discussed specifically. Within this simplified framework it is shown that the strong electromagnetic fields can play a catalyzing role for a deconfinement transition. At the qualitative level, the present consideration can be seen as a highly simplified study of an impact of the electromagnetic fields generated in relativistic heavy ion collisions on the strongly interacting hadronic matter.

  11. Perspective has a strong effect on the calculation of historical contributions to global warming

    Science.gov (United States)

    Skeie, Ragnhild B.; Fuglestvedt, Jan; Berntsen, Terje; Peters, Glen P.; Andrew, Robbie; Allen, Myles; Kallbekken, Steffen

    2017-02-01

    The politically contentious issue of calculating countries’ contributions to climate change is strongly dependent on methodological choices. Different principles can be applied for distributing efforts for reducing human-induced global warming. According to the ‘Brazilian Proposal’, industrialized countries would reduce emissions proportional to their historical contributions to warming. This proposal was based on the assumption that the political process would lead to a global top-down agreement. The Paris Agreement changed the role of historical responsibilities. Whereas the agreement refers to equity principles, differentiation of mitigation efforts is delegated to each country, as countries will submit new national contributions every five years without any international negotiation. It is likely that considerations of historical contributions and distributive fairness will continue to play a key role, but increasingly so in a national setting. Contributions to warming can be used as a background for negotiations to inform and justify positions, and may also be useful for countries’ own assessment of what constitutes reasonable and fair contributions to limiting warming. Despite the fact that the decision from COP21 explicitly rules out compensation in the context of loss and damage, it is likely that considerations of historical responsibility will also play a role in future discussions. However, methodological choices have substantial impacts on calculated contributions to warming, including rank-ordering of contributions, and thus support the view that there is no single correct answer to the question of how much each country has contributed. There are fundamental value-related and ethical questions that cannot be answered through a single set of calculated contributions. Thus, analyses of historical contributions should not present just one set of results, but rather present a spectrum of results showing how the calculated contributions vary with a

  12. Strong synergistic effects in PLA/PCL blends: Impact of PLA matrix viscosity.

    Science.gov (United States)

    Ostafinska, Aleksandra; Fortelný, Ivan; Hodan, Jiří; Krejčíková, Sabina; Nevoralová, Martina; Kredatusová, Jana; Kruliš, Zdeněk; Kotek, Jiří; Šlouf, Miroslav

    2017-05-01

    Blends of two biodegradable polymers, poly(lactic acid) (PLA) and poly(ϵ-caprolactone) (PCL), with strong synergistic improvement in mechanical performance were prepared by melt-mixing using the optimized composition (80/20) and the optimized preparation procedure (a melt-mixing followed by a compression molding) according to our previous study. Three different PLA polymers were employed, whose viscosity decreased in the following order: PLC ≈ PLA1 > PLA2 > PLA3. The blends with the highest viscosity matrix (PLA1/PCL) exhibited the smallest PCL particles (d∼0.6μm), an elastic-plastic stable fracture (as determined from instrumented impact testing) and the strongest synergistic improvement in toughness (>16× with respect to pure PLA, exceeding even the toughness of pure PCL). According to the available literature, this was the highest toughness improvement in non-compatiblized PLA/PCL blends ever achieved. The decrease in the matrix viscosity resulted in an increase in the average PCL particle size and a dramatic decrease in the overall toughness: the completely stable fracture (for PLA1/PCL) changed to the stable fracture followed by unstable crack propagation (for PLA2/PCL) and finally to the completely brittle fracture (for PLA3/PCL). The stiffness of all blends remained at well acceptable level, slightly above the theoretical predictions based on the equivalent box model. Despite several previous studies, the results confirmed that PLA and PCL could behave as compatible polymers, but the final PLA/PCL toughness is extremely sensitive to the PCL particle size distribution, which is influenced by both processing conditions and PLA viscosity. PLA/PCL blends with high stiffness (due to PLA) and toughness (due to PCL) are very promising materials for medical applications, namely for the bone tissue engineering. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Effects of a parental program for preventing underage drinking - The NGO program strong and clear

    Directory of Open Access Journals (Sweden)

    Eriksson Charli

    2011-04-01

    Full Text Available Abstract Background The present study is an evaluation of a 3-year parental program aiming to prevent underage drinking. The intervention was implemented by a non-governmental organization and targeted parents with children aged 13-16 years old and included recurrent activities during the entire period of secondary school. The program consisted of four different types of group and self-administered activities: parent meetings, family dialogues, friend meetings, and family meetings. Methods A quasi-experimental design was used following parents and children with questionnaires during the three years of secondary school. The analytic sample consisted of 509 dyads of parents and children. Measures of parental attitudes and behaviour concerning underage drinking and adolescents' lifetime alcohol consumption and drunkenness were used. Three socio-demographic factors were included: parental education, school, and gender of the child. A Latent Growth Modelling (LGM approach was used to examine changes in parental behaviour regarding youth drinking and in young people's drinking behaviour. To test for the pre-post test differences in parental attitudes repeated measures ANOVA were used. Results The results showed that parents in the program maintained their restrictive attitude toward underage drinking to a higher degree than non-participating parents. Adolescents of participants were on average one year older than adolescents with non-participating parents when they made their alcohol debut. They were also less likely to have ever been drunk in school year 9. Conclusion The results of the study suggested that Strong and Clear contributed to maintaining parents' restrictive attitude toward underage drinking during secondary school, postponing alcohol debut among the adolescents, and significantly reducing their drunkenness.

  14. Extrinsic tooth stain removal efficacy of a sodium bicarbonate dual-phase dentifrice containing calcium and phosphate in a six-week clinical trial.

    Science.gov (United States)

    Putt, Mark S; Milleman, Jeffery L; Ghassemi, Annahita

    2004-01-01

    The objective of this clinical investigation was to evaluate the effectiveness in removing existing extrinsic tooth stains of a sodium bicarbonate (baking soda), dual-phase dentifrice containing calcium and phosphate (Test Dentifrice), when compared to a commercial hydrated silica dentifrice (Control Dentifrice), during a six-week period of normal, unsupervised use. This investigation was a double-blind comparison of two equivalent, parallel groups of subjects assigned to use different dentifrices for six weeks. A total of 108 adult male and female subjects qualified for the trial based on the presence of existing extrinsic tooth stains and other inclusion/exclusion criteria. The two groups were balanced for gender, tobacco use, and extrinsic tooth stain scores, and randomly assigned the Test or Control dentifrices. All subjects were instructed to brush their teeth twice daily using only the dentifrice and toothbrush provided, and to refrain from using any other oral hygiene products for the duration of the study. Although product usage was unsupervised after the baseline visit, subjects maintained a treatment diary, and product consumption was monitored to estimate compliance. Oral soft and hard tissue and extrinsic stain assessments (Modified Lobene Stain Index) for each subject were conducted at baseline and after two, four, and six weeks of product use. A total of 107 subjects complied with the protocol and completed the six-week study. Compared to baseline, at the two-, four-, and six-week examinations the Test Dentifrice group had statistically significant reductions in extrinsic tooth stain. In contrast, the Control Dentifrice group did not attain significant reductions from baseline at any of the exams. At both the four-week and six-week examinations, the Test Dentifrice group had significantly lower levels of extrinsic tooth stain than the Control Dentifrice group. A sodium bicarbonate, dual-phase dentifrice containing calcium and phosphate demonstrated

  15. How strong is the edge effect in the adsorption of anticancer drugs on a graphene cluster?

    Science.gov (United States)

    Rungnim, Chompoonut; Chanajaree, Rungroj; Rungrotmongkol, Thanyada; Hannongbua, Supot; Kungwan, Nawee; Wolschann, Peter; Karpfen, Alfred; Parasuk, Vudhichai

    2016-04-01

    The adsorption of nucleobase-analog anticancer drugs (fluorouracil, thioguanine, and mercaptopurine) on a graphene flake (C54H18) was investigated by shifting the site at which adsorption occurs from one end of the sheet to the other end. The counterpoise-corrected M06-2X/cc-pVDZ binding energies revealed that the binding stability decreases in the sequence thioguanine > mercaptopurine > fluorouracil. We found that adsorption near the middle of the sheet is more favorable than adsorption near the edge due to the edge effect. This edge effect is stronger for the adsorption of thioguanine or mercaptopurine than for fluorouracil adsorption. However, the edge effect reduces the binding energy of the drug to the flake by only a small amount, <5 kcal/mol, depending on the adsorption site and the alignment of the drug at this site.

  16. Castanea sativa Mill. bark extract exhibits chemopreventive properties triggering extrinsic apoptotic pathway in Jurkat cells.

    Science.gov (United States)

    Lenzi, Monia; Malaguti, Marco; Cocchi, Veronica; Hrelia, Silvana; Hrelia, Patrizia

    2017-05-05

    Chemoprevention represents the possibility to prevent, stop or reverse the cancerogenetic process. In this context the interest towards natural extracts and botanical drugs has constantly grown due to their phytochemical content. Castanea sativa Mill. (CSM) extracts showed to exert positive effect in the prevention/counteraction of chronic/degenerative diseases, therefore, we evaluated the potential chemopreventive effect of CSM bark extract. Flow cytometry (FCM) analyses of Jurkat cells treated with CSM bark extract (0-500 μg·mL -1 ) for 24-72 h allowed evaluating its cytotoxicity and ability to induce apoptosis through the intrinsic or extrinsic pathways. Moreover, to evaluate CSM bark extract selectivity towards cancer cells, its cytotoxic and pro-apoptotic effect was also evaluated in human peripheral blood lymphocytes (PBL). CSM bark extract induced apoptosis in Jurkat cells in a dose- and time- dependent manner activating the extrinsic pathways as evidenced by the increase of activated caspase-8 positive cells. Moreover, IC 50 calculated after 24 h treatment resulted 304 and 128 μg·mL -1 in PBL and Jurkat cells respectively. Our data suggest that CSM bark extract might be considered an interesting potential anti-cancer agent, since it induces apoptosis in cancer cells without appreciable cytotoxic effects on non-transformed cells.

  17. Strong excitonic effects in CuAlO2 delafossite transparent conductive oxides

    DEFF Research Database (Denmark)

    Laskowski, Robert; Christensen, Niels Egede; Blaha, Peter

    2009-01-01

    The imaginary part of the dielectric function of CuAlO2 has been calculated including the electron-hole correlation effects within Bethe-Salpeter formalism (BSE). In the initial step of the BSE solver the band structure was calculated within density-functional theory plus an orbital field (LDA/GG...

  18. Rapid Transition of the Hole Rashba Effect from Strong Field Dependence to Saturation in Semiconductor Nanowires.

    Science.gov (United States)

    Luo, Jun-Wei; Li, Shu-Shen; Zunger, Alex

    2017-09-22

    The electric field manipulation of the Rashba spin-orbit coupling effects provides a route to electrically control spins, constituting the foundation of the field of semiconductor spintronics. In general, the strength of the Rashba effects depends linearly on the applied electric field and is significant only for heavy-atom materials with large intrinsic spin-orbit interaction under high electric fields. Here, we illustrate in 1D semiconductor nanowires an anomalous field dependence of the hole (but not electron) Rashba effect (HRE). (i) At low fields, the strength of the HRE exhibits a steep increase with the field so that even low fields can be used for device switching. (ii) At higher fields, the HRE undergoes a rapid transition to saturation with a giant strength even for light-atom materials such as Si (exceeding 100 meV Å). (iii) The nanowire-size dependence of the saturation HRE is rather weak for light-atom Si, so size fluctuations would have a limited effect; this is a key requirement for scalability of Rashba-field-based spintronic devices. These three features offer Si nanowires as a promising platform for the realization of scalable complementary metal-oxide-semiconductor compatible spintronic devices.

  19. Effect of strong electrolytes on edible oils part 1: viscosity of ...

    African Journals Online (AJOL)

    The energy of activation (ΔEv), latent heat of vapourization (ΔLv) and molar volume of oil (Vm) were also calculated. Effect of electrolytes show that, the concentration of electrolytes increases the value of (ΔEv) and (ΔLv) whereas the value of molar volume (Vm) decrease with the concentration of oil and electrolytes. In brief ...

  20. Effect of strong electrolytes on edible oils part II: vViscosity of maize ...

    African Journals Online (AJOL)

    The electrolytes behave as structure breaker. The effect of temperature was also determined in terms of fluidity parameters, energy of activation, latent heat of vaporization, molar volume of oil and free energy change of activation for viscous flow. Journal of Applied Sciences and Environmental Management Vol. 10 (3) 2006: ...

  1. Faraday effect in rare-earth ferrite garnets located in strong magnetic fields

    International Nuclear Information System (INIS)

    Valiev, U.V.; Zvezdin, A.K.; Krinchik, G.S.; Levitin, R.Z.; Mukimov, K.M.; Popov, A.I.

    1983-01-01

    The Faraday effect is investigated experimentally in single crystal specimens of rare earth iron garnets (REIG) R 3 Fe 5 O 12 (R=Y, Gd, Tb, Dy, Er, Tm, Yb, Eu, Sm and Ho) and also in mixed iron garnets Rsub(x)Ysub(3-x)Fesub(5)Osub(12) (R=Tb, Dy). The m.easurements are carried out in pulsed magnetic fields of intensity up to 200 kOe, in a temperature range from 4.2 to 300 K and at a wavelength of the light lambda=1.15 μm. The field dependence of the Faraday effect observed in the REIG cannot be explained if only the usually considered ''paramagnetic'' contribution to the Faraday effect is taken into account. A theory is developed which, besides the paramagnetic mechanism, takes into account a diamagnetic mechanism and also the mixing of the wave functions of the ground and excited multiplets. The contributions of each of these three mechanisms to the angle of rotation of the plane of polarization by the rare earth sublattice of the iron garnet are estimated theoretically. It is concluded that the mixing mechanism contributes significantly to the field and temperature dependences of the Faraday effect in REIG

  2. Effect of inter-fibre bonding on the fracture of fibrous networks with strong interactions

    DEFF Research Database (Denmark)

    Goutianos, Stergios; Mao, Rui; Peijs, Ton

    2017-01-01

    Abstract The mechanical response of cellulose nanopaper composites is investigated using a three-dimensional (3D) finite element fibrous network model with focus on the effect of inter-fibre bonds. It is found that the Young’s modulus and strength, for fixed fibre properties, are mainly controlle...

  3. Fourier heat conduction as a strong kinetic effect in one-dimensional hard-core gases

    Science.gov (United States)

    Zhao, Hanqing; Wang, Wen-ge

    2018-01-01

    For a one-dimensional (1D) momentum conserving system, intensive studies have shown that generally its heat current autocorrelation function (HCAF) tends to decay in a power-law manner and results in the breakdown of the Fourier heat conduction law in the thermodynamic limit. This has been recognized to be a dominant hydrodynamic effect. Here we show that, instead, the kinetic effect can be dominant in some cases and leads to the Fourier law for finite-size systems. Usually the HCAF undergoes a fast decaying kinetic stage followed by a long slowly decaying hydrodynamic tail. In a finite range of the system size, we find that whether the system follows the Fourier law depends on whether the kinetic stage dominates. Our Rapid Communication is illustrated by the 1D hard-core gas models with which the HCAF is derived analytically and verified numerically by molecular dynamics simulations.

  4. A temporo-spatial analysis of the neural correlates of extrinsic perceptual grouping in vision.

    Science.gov (United States)

    Montoro, Pedro R; Luna, Dolores; Albert, Jacobo; Santaniello, Gerardo; López-Martín, Sara; Pozo, Miguel A; Hinojosa, José A

    2015-03-01

    Principles of perceptual grouping can be divided into intrinsic grouping cues, which are based on built-in properties of the grouped elements (e.g., their shape, position, colour, etc.) like most of the classical Gestalt laws, and extrinsic grouping principles, based on relations between the discrete elements and other external stimuli that induce them to group (e.g., common region, connectedness). Several studies have explored the neural correlates of intrinsic grouping factors but, to our knowledge, no previous study has studied the neural correlates of extrinsic principles. The present study aimed to shed light on this issue by exploiting the high temporal resolution of event-related potentials (ERPs) and recent advances in source localization. Specifically, grouping by common region was compared with two comparison conditions, an intrinsic grouping (luminance similarity) and a uniform stimulus condition, in a perceptual discrimination task. We reported three main neural effects associated with grouping by common region. First, a posterior N210 component with a neural origin in the left extrastriate cortex was related to perceptual analysis of extrinsic elements inducing grouping and the formation of a visual group. Second, an enhanced posterior P280, which presumably reflects higher confidence decisions during response selection. Finally, a P550 originated in the right superior parietal cortex that seems to be associated with top-down suppression activity connected with the termination of the processing of the current trial. Overall, our results suggest that common region cues belong to the category of long latency grouping principles that mainly involve activity in extrastriate cortices. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Biological Maturity Status Strongly Intensifies the Relative Age Effect in Alpine Ski Racing.

    Directory of Open Access Journals (Sweden)

    Lisa Müller

    Full Text Available The relative age effect (RAE is a well-documented phenomenon in youth sports. This effect exists when the relative age quarter distribution of selected athletes shows a biased distribution with an over-representation of relatively older athletes. In alpine ski racing, it exists in all age categories (national youth levels up to World Cup. Studies so far could demonstrate that selected ski racers are relatively older, taller and heavier. It could be hypothesized that relatively younger athletes nearly only have a chance for selection if they are early maturing. However, surprisingly this influence of the biological maturity status on the RAE could not be proven, yet. Therefore, the aim of the present study was to investigate the influence of the biological maturity status on the RAE in dependence of the level of competition. The study investigated 372 elite youth ski racers: 234 provincial ski racers (P-SR; high level of competition and 137 national ski racers (N-SR; very high level of competition. Anthropometric characteristics were measured to calculate the age at peak height velocity (APHV as an indicator of the biological maturity status. A significant RAE was present among both P-SR and N-SR, with a larger effect size among the latter group. The N-SR significantly differed in APHV from the P-SR. The distribution of normal, early and late maturing athletes significantly differed from the expected normal distribution among the N-SR, not among the P-SR. Hardly any late maturing N-SR were present; 41.7% of the male and 34% of the female N-SR of the last relative age quarter were early maturing. These findings clearly demonstrate the significant influence of the biological maturity status on the selection process of youth alpine ski racing in dependence of the level of competition. Relatively younger athletes seem to have a chance of selection only if they are early maturing.

  6. Biological Maturity Status Strongly Intensifies the Relative Age Effect in Alpine Ski Racing.

    Science.gov (United States)

    Müller, Lisa; Müller, Erich; Hildebrandt, Carolin; Raschner, Christian

    2016-01-01

    The relative age effect (RAE) is a well-documented phenomenon in youth sports. This effect exists when the relative age quarter distribution of selected athletes shows a biased distribution with an over-representation of relatively older athletes. In alpine ski racing, it exists in all age categories (national youth levels up to World Cup). Studies so far could demonstrate that selected ski racers are relatively older, taller and heavier. It could be hypothesized that relatively younger athletes nearly only have a chance for selection if they are early maturing. However, surprisingly this influence of the biological maturity status on the RAE could not be proven, yet. Therefore, the aim of the present study was to investigate the influence of the biological maturity status on the RAE in dependence of the level of competition. The study investigated 372 elite youth ski racers: 234 provincial ski racers (P-SR; high level of competition) and 137 national ski racers (N-SR; very high level of competition). Anthropometric characteristics were measured to calculate the age at peak height velocity (APHV) as an indicator of the biological maturity status. A significant RAE was present among both P-SR and N-SR, with a larger effect size among the latter group. The N-SR significantly differed in APHV from the P-SR. The distribution of normal, early and late maturing athletes significantly differed from the expected normal distribution among the N-SR, not among the P-SR. Hardly any late maturing N-SR were present; 41.7% of the male and 34% of the female N-SR of the last relative age quarter were early maturing. These findings clearly demonstrate the significant influence of the biological maturity status on the selection process of youth alpine ski racing in dependence of the level of competition. Relatively younger athletes seem to have a chance of selection only if they are early maturing.

  7. Foraging strategy of a Neotropical primate: how intrinsic and extrinsic factors influence destination and residence time

    DEFF Research Database (Denmark)

    Plante, Sabrina; Colchero, Fernando; Calmé, Sophie

    2014-01-01

    accounting for intrinsic and extrinsic factors, which are often overlooked when modelling foraging behaviour. 2.We identified the decision rules for foraging in black howler monkeys (Alouatta pigra), according to food preferences, locations of high quality patches and previously eaten trees, phenology...... of food resources and hunger state. We depicted foraging in two stages: 1) the choice of the immediate next tree and 2) the time spent on this tree. We used a recently developed model for inference of movement processes, incorporating resource selection functions into a Markov Chain framework. 3.We found....... Time spent on a tree was positively and strongly affected by the presence of preferred food items, but not by its species. We also showed that time spent on trees increased as a function of satiation state. We suggest that the strategy adopted by black howlers tends to be efficient because choosing...

  8. A systematic review of drug treatment of vulvodynia: evidence of a strong placebo effect.

    Science.gov (United States)

    Varella Pereira, Glaucia Miranda; Marcolino, Milena Soriano; Nogueira Reis, Zilma Silveira; de Castro Monteiro, Marilene Vale

    2018-03-23

    Vulvodynia is the most common type of chronic pelvic pain and dyspareunia in premenopausal women. The effect of drugs for the treatment of vulvodynia remains poorly discussed. To conduct a systematic review of randomised controlled studies which assess medications used to treat vulvar pain in vulvodynia. Web of Science, Cochrane Library, EBSCO Academic, LILACS and MEDLINE were searched from 1985 to September 2016. Randomised controlled trials comparing any kind of medication for vulvodynia treatment with placebo or with another medication in adult patients were included. The two investigators independently conducted data extraction. The synthesis was provided by the pain reduction index. Study quality assessment was performed using the Cochrane Handbook for Systematic Reviews of Intervention and analysis of publication bias was conducted. Five studies were included in qualitative synthesis with a number of the participants varied from 30 to 133 among the eligible studies resulting 297. The pain reduction rates of patients with vulvodynia assessed by Q-tipped Cotton Test and visual analogue scale varied between studies. Placebo was shown to be as effective as any medication. There is a need for further studies evaluating topical monotherapy for the treatment of vulvodynia, since they are the main drugs used in clinical practice. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. <strong>Dimensional asymptotics of effective actions on S^n, and proof of Bär-Schopka's conjecturestrong>

    DEFF Research Database (Denmark)

    Møller, Niels Martin

    We study the dimensional asymptotics of the effective actions, or functional determinants, for the Dirac operator D and Laplacians \\Delta +\\beta R on round S^n. For Laplacians the behavior depends on ``the coupling strength'' \\beta, and one cannot in general expect a finite limit of \\zeta'(0), an...... spheres to unit volume, since \\lim_{k\\to\\infty}\\det(\\Delta, S_\\mathrm{rescaled}^{2k+1})=\\frac{1}{2\\pi e}....

  10. Effects of strong network modifiers on Fe3+/Fe2+ in silicate melts: an experimental study

    Science.gov (United States)

    Borisov, Alexander; Behrens, Harald; Holtz, Francois

    2017-05-01

    The effect of CaO, Na2O, and K2O on ferric/ferrous ratio in model multicomponent silicate melts was investigated in the temperature range 1450-1550 °C at 1-atm total pressure in air. It is demonstrated that the addition of these network modifier cations results in an increase of Fe3+/Fe2+ ratio. The influence of network modifier cations on the ferric/ferrous ratio increases in the order Ca SiO2-TiO2-Al2O3-FeO-Fe2O3-MgO-CaO-Na2O-K2O-P2O5 melts at air conditions.

  11. In-medium covariant propagator of baryons under a strong magnetic field: Effect of the intrinsic magnetic moments

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre, R.M.; Paoli, A.L. de [Universidad Nacional de La Plata, and IFLP, Departamento de Fisica, Facultad de Ciencias Exactas, La Plata (Argentina)

    2016-11-15

    We obtain the covariant propagator at finite temperature for interacting baryons immersed in a strong magnetic field. The effect of the intrinsic magnetic moments on the Green function are fully taken into account. We make an expansion in terms of eigenfunctions of a Dirac field, which leads us to a compact form of its propagator. We present some simple applications of these propagators, where the statistical averages of nuclear currents and energy density are evaluated. (orig.)

  12. Absence of strong strain effects in behavioral analyses of Shank3-deficient mice

    Directory of Open Access Journals (Sweden)

    Elodie Drapeau

    2014-06-01

    Full Text Available Haploinsufficiency of SHANK3, caused by chromosomal abnormalities or mutations that disrupt one copy of the gene, leads to a neurodevelopmental syndrome called Phelan-McDermid syndrome, symptoms of which can include absent or delayed speech, intellectual disability, neurological changes and autism spectrum disorders. The SHANK3 protein forms a key structural part of the post-synaptic density. We previously generated and characterized mice with a targeted disruption of Shank3 in which exons coding for the ankyrin-repeat domain were deleted and expression of full-length Shank3 was disrupted. We documented specific deficits in synaptic function and plasticity, along with reduced reciprocal social interactions, in Shank3 heterozygous mice. Changes in phenotype owing to a mutation at a single locus are quite frequently modulated by other loci, most dramatically when the entire genetic background is changed. In mice, each strain of laboratory mouse represents a distinct genetic background and alterations in phenotype owing to gene knockout or transgenesis are frequently different across strains, which can lead to the identification of important modifier loci. We have investigated the effect of genetic background on phenotypes of Shank3 heterozygous, knockout and wild-type mice, using C57BL/6, 129SVE and FVB/Ntac strain backgrounds. We focused on observable behaviors with the goal of carrying out subsequent analyses to identify modifier loci. Surprisingly, there were very modest strain effects over a large battery of analyses. These results indicate that behavioral phenotypes associated with Shank3 haploinsufficiency are largely strain-independent.

  13. Extrinsic coefficient charcterisation of PZT ceramics near the morphotropic phase boundary

    Directory of Open Access Journals (Sweden)

    Albareda, A.

    2006-06-01

    Full Text Available PZT ceramics with high piezoelectric coefficients have high extrinsic contributions. This extrinsic behaviour, which is related to the domain wall movement, produces high non-linear effects that are sometimes inconvenient, for example when it increases the losses in power devices. The relation between extrinsic behaviour and non-linearities could be used to provide a good extrinsic characterization of materials in order to optimise the piezoelectric devices. In all cases the physical explanation of the behaviour is sought. The aim of this work is to study the dependence of the linear and non-linear dielectric, piezoelectric and mechanical coefficients on the Ti fraction in PZT ceramic compositions near the morphotropic phase boundary (MPB. The dependence of these coefficients on the defect concentration is also analysed. Hard ceramics belonging to Ferroperm Piezoceramics, with two different acceptor dopant levels, high and low, have been measured.

    Las cerámicas PZT con coeficientes piezoeléctricos elevados poseen contribuciones extrínsecas grandes. Este comportamiento extrínseco, relacionado con el movimiento de las paredes de los dominios, comporta efectos no lineales grandes que no siempre son deseables, por ejemplo, al incrementar las pérdidas de los dispositivos piezoeléctricos. Esta correspondencia entre efectos extrínsecos y no linealidades puede ser utilizada para caracterizar las cerámicas con el fin de optimizar sus propiedades piezoeléctricas. En todos los casos se busca una interpretación física de los resultados obtenidos. El objetivo de este trabajo es el estudio de la dependencia de los coeficientes lineales y no lineales dieléctricos, piezoeléctricos y elásticos con la fracción de Ti en cerámicas PZT con composiciones de Zr-Ti cerca de la transición de fase morfotrópica (MPB. También se analiza la dependencia de estos coeficientes con la concentración de impurezas, utilizando para ello cerámicas de

  14. Effects of strong electron correlations in Ti8C12 Met-Car

    International Nuclear Information System (INIS)

    Varganov, Sergey A.; Gordon, Mark S.

    2006-01-01

    The results of multireference configuration interaction (MRCI) with single and double excitations and single reference coupled cluster (CCSD(T)) calculations on Ti 8 C 12 metallocarbohedryne (Met-Car) are reported. The distortions of the T d structure to D 2d and C 3v structures due to the Jahn-Teller effect are studied. It is shown that the Ti 8 C 12 wave function has significant multireference character. The choice of the active space for multireference self-consistent field (MCSCF) calculations is discussed. The failure of multireference perturbation theory with a small active space is attributed to multiple intruder states. A new, novel type of MCSCF calculation, ORMAS (occupation restricted multiple active spaces) with a large active space are carried out for several electronic states of Ti 8 C 12 . The Jahn-Teller distorted D 2d 1 A 1 (nearly T d ) structure is predicted to be the Ti 8 C 12 ground state. Predictions of the Ti 8 C 12 ionization potential with different ab initio methods are presented

  15. Noise-induced effects on multicellular biopacemaker spontaneous activity: Differences between weak and strong pacemaker cells

    Science.gov (United States)

    Aghighi, Alireza; Comtois, Philippe

    2017-09-01

    Self-organization of spontaneous activity of a network of active elements is important to the general theory of reaction-diffusion systems as well as for pacemaking activity to initiate beating of the heart. Monolayer cultures of neonatal rat ventricular myocytes, consisting of resting and pacemaker cells, exhibit spontaneous activation of their electrical activity. Similarly, one proposed approach to the development of biopacemakers as an alternative to electronic pacemakers for cardiac therapy is based on heterogeneous cardiac cells with resting and spontaneously beating phenotypes. However, the combined effect of pacemaker characteristics, density, and spatial distribution of the pacemaker cells on spontaneous activity is unknown. Using a simple stochastic pattern formation algorithm, we previously showed a clear nonlinear dependency of spontaneous activity (occurrence and amplitude of spontaneous period) on the spatial patterns of pacemaker cells. In this study, we show that this behavior is dependent on the pacemaker cell characteristics, with weaker pacemaker cells requiring higher density and larger clusters to sustain multicellular activity. These multicellular structures also demonstrated an increased sensitivity to voltage noise that favored spontaneous activity at lower density while increasing temporal variation in the period of activity. This information will help researchers overcome the current limitations of biopacemakers.

  16. Theory of extrinsic and intrinsic heterojunctions in thermal equilibrium

    Science.gov (United States)

    Von Ross, O.

    1980-01-01

    A careful analysis of an abrupt heterojunction consisting of two distinct semiconductors either intrinsic or extrinsic is presented. The calculations apply to a one-dimensional, nondegenerate structure. Taking into account all appropriate boundary conditions, it is shown that the intrinsic Fermi level shows a discontinuity at the interface between the two materials which leads to a discontinuity of the valence band edge equal to the difference in the band gap energies of the two materials. The conduction band edge stays continuous however. This result is independent of possible charged interface states and in sharp contrast to the Anderson model. The reasons for this discrepancy are discussed.

  17. Alberta Consumers' Valuation of Extrinsic and Intrinsic Red Meat Attributes

    DEFF Research Database (Denmark)

    Steiner, Bodo; Gao, Fei; Unterschultz, Jim

    2010-01-01

    This paper analyzes Alberta consumers’ perceptions toward extrinsic and intrinsic attributes of bison and beef steaks. In contrast to published Canadian consumer studies on bison meat that were undertaken prior to May 2003, before the first BSE case of Canadian origin was identified in beef cattle......, this study provides a “post-BSE” assessment of consumer perceptions toward selected bison meat attributes. The results from an attribute-based choice experiment provide little support that simple traceability assurance schemes have value to consumers of bison and beef steaks, thus confirming similar findings...

  18. Older adults' intrinsic and extrinsic motivation toward physical activity.

    Science.gov (United States)

    Dacey, Marie; Baltzell, Amy; Zaichkowsky, Len

    2008-01-01

    To examine how motives discriminate 3 physical activity levels of inactive, active, and sustained maintainers. Six hundred forty-five adults (M age = 63.8) completed stage-of-change and Exercise Motivations Inventory (EMI-2) scales. Exploratory factor analysis established psychometric properties of the EMI-2 suitable for older adults. Six factors emerged in the EMI-2: health and fitness, social/emotional benefits, weight management, stress management, enjoyment, and appearance. Enjoyment contributed most to differentiating activity levels. Moderators of age and gender were delineated. Intrinsic motivation and self-determined extrinsic motivation distinguish older adults' activity levels.

  19. Intrinsic and extrinsic magnetic properties of the naturally layered manganites

    International Nuclear Information System (INIS)

    Berger, A.; Mitchell, J. F.; Miller, D. J.; Jiang, J. S.; Bader, S. D.

    1999-01-01

    Structural and magnetic properties of the two-layered Ruddlesden-Popper phase SrO(La 1-x Sr x MnO 3 ) 2 with x = 0.3--0.5 are highlighted. Intrinsic properties of these naturally layered manganites include a colossal magnetoresistance, a composition-dependent magnetic anisotropy, and almost no remanence. Above the Curie temperature there is a non-vanishing extrinsic magnetization attributed to intergrowths (stacking faults in the layered structure). These lattice imperfections consist of additional or missing manganite layers, as observed in transmission electron microscopy. Their role in influencing the properties of the host material is highlighted

  20. <strong>EFFECTS OF HYALURONAN ON THREE-DIMENSIONAL MICROARCHITECTURE OF SUBCHONDRAL BONE TISSUES IN GUINEA PIG PRIMARY OSTEOARTHROSISstrong>

    DEFF Research Database (Denmark)

    Ding, Ming

    ; and the control groups received vehicle. After sacrifice, the left tibiae were harvested and micro-CT scanned, followed by mechanical testing and collagen and mineral determination. Results: The HA-treated groups had almost normal cartilage, whereas the control groups had typical osteoarthrosis (OA......-term study, these latter changes were more pronounced, with an additionally significant decrease in connectivity and bone surface density. HA groups had greater bone mineral concentration and mineral density, lower collagen to mineral ratio, and preserved the mechanical properties of cancellous bone...... level, and effectively changes the subchondral bone tissue microarchitecture, collagen and mineral content and density without altering the mechanical properties of cancellous bone. The most striking features are the microarchitectural changes in the subchondral cancellous bone that lead to lower bone...

  1. A Solar Eruption from a Weak Magnetic Field Region with Relatively Strong Geo-Effectiveness

    Science.gov (United States)

    Wang, R.

    2017-12-01

    A moderate flare eruption giving rise to a series of geo-effectiveness on 2015 November 4 caught our attentions, which originated from a relatively weak magnetic field region. The associated characteristics near the Earth are presented, which indicates that the southward magnetic field in the sheath and the ICME induced a geomagnetic storm sequence with a Dst global minimum of 90 nT. The ICME is indicated to have a small inclination angle by using a Grad-Shafranov technique, and corresponds to the flux rope (FR) structure horizontally lying on the solar surface. A small-scale magnetic cancelling feature was detected which is beneath the FR and is co-aligned with the Atmospheric Imaging Assembly (AIA) EUV brightening prior to the eruption. Various magnetic features for space-weather forecasting are computed by using a data product from the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) called Space-weather HMI Active Region Patches (SHARPs), which help us identify the changes of the photospheric magnetic fields during the magnetic cancellation process and prove that the magnetic reconnection associated with the flux cancellation is driven by the magnetic shearing motion on the photosphere. An analysis on the distributions at different heights of decay index is carried out. Combining with a filament height estimation method, the configurations of the FR is identified and a decay index critical value n = 1 is considered to be more appropriate for such a weak magnetic field region. Through a comprehensive analysis to the trigger mechanisms and conditions of the eruption, a clearer scenario of a CME from a relatively weak region is presented.

  2. Maturity Status Strongly Influences the Relative Age Effect in International Elite Under-9 Soccer

    Directory of Open Access Journals (Sweden)

    Lisa Müller, Josef Gehmaier, Christoph Gonaus, Christian Raschner, Erich Müller

    2018-06-01

    Full Text Available The aim of the study was to assess the role of the relative age effect (RAE and to investigate the influence of the biological maturity status on the RAE in international under-9 soccer. The birth dates of 222 male participants of the U9 Eurochampionship Soccer Tournament in Vienna in 2016 were analyzed and divided into four relative age quarters (Q1-Q4 and the biological maturity status was assessed with the age at peak height velocity (APHV method. Based on the mean±standard deviation of the APHV, the athletes were divided into three groups of maturity: early, normal and late maturing. Chi-Square-tests were used to assess the difference between the observed and the expected even relative age quarter distribution and to evaluate the difference between the observed distribution of early, normal and late maturing athletes and the expected normal distribution. A univariate analysis of variance was performed to assess differences in the APHV between the relative age quarters. A RAE was present (χ2 = 23.87; p < 0.001; ω = 0.33. A significant difference was found in APHV between the four relative age quarters (F = 9.906; p < 0.001; relatively older athletes were significantly less mature. A significant difference was found between the distribution of early, normal and late maturing athletes and the expected normal distribution for athletes of Q1 (high percentage of late maturing athletes: 27%; χ2 = 17.69; p < 0.001; ω = 0.46 and of Q4 (high percentage of early maturing soccer players: 31%; χ2 = 12.08; p = 0.002; ω = 0.58. These findings demonstrated that the selection process in international soccer, with athletes younger than 9 years, seems to be associated with the biological maturity status and the relative age. Relatively younger soccer players seem to have a better chance for selection for international tournaments, if they enter puberty at an earlier age, whereas relatively older athletes seem to have an increased likelihood for

  3. Self-assembly of a novel beta-In2S3 nanostructure exhibiting strong quantum confinement effects.

    Science.gov (United States)

    Zhang, Wu; Ma, Dekun; Huang, Zhen; Tang, Qun; Xie, Qin; Qian, Yitai

    2005-05-01

    The 3D beta-In2S3 flowerlike architecture assembled from nanoflakes was prepared via a novel complex-precursor assisted (CPA) solvothermal route. The as-prepared beta-In2S3 powder was characterized by X-ray diffraction pattern (XRD), X-ray photoelectron spectra (XPS), transition electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), ultraviolet-visible light (UV-vis) spectra, and photoluminescence spectrum. The novel 3D beta-In2S3 nanostructure exhibit a strong quantum confinement effect. FT-IR spectra were used to investigate the coordinative chemical effect in the complex. A possible mechanism was discussed.

  4. Hall effect in a strong magnetic field: Direct comparisons of compressible magnetohydrodynamics and the reduced Hall magnetohydrodynamic equations

    International Nuclear Information System (INIS)

    Martin, L. N.; Dmitruk, P.; Gomez, D. O.

    2010-01-01

    In this work we numerically test a model of Hall magnetohydrodynamics in the presence of a strong mean magnetic field: the reduced Hall magnetohydrodynamic model (RHMHD) derived by [Gomez et al., Phys. Plasmas 15, 102303 (2008)] with the addition of weak compressible effects. The main advantage of this model lies in the reduction of computational cost. Nevertheless, up until now the degree of agreement with the original Hall MHD system and the range of validity in a regime of turbulence were not established. In this work direct numerical simulations of three-dimensional Hall MHD turbulence in the presence of a strong mean magnetic field are compared with simulations of the weak compressible RHMHD model. The results show that the degree of agreement is very high (when the different assumptions of RHMHD, such as spectral anisotropy, are satisfied). Nevertheless, when the initial conditions are isotropic but the mean magnetic field is maintained strong, the results differ at the beginning but asymptotically reach a good agreement at relatively short times. We also found evidence that the compressibility still plays a role in the dynamics of these systems, and the weak compressible RHMHD model is able to capture these effects. In conclusion the weak compressible RHMHD model is a valid approximation of the Hall MHD turbulence in the relevant physical context.

  5. Examining extrinsic factors that influence product acceptance: a review.

    Science.gov (United States)

    Li, X E; Jervis, S M; Drake, M A

    2015-05-01

    Drivers of liking (DOL) studies are useful for product development to formulate acceptable products; however, DOL alone are insufficient for understanding why a product is purchased and repurchased, which is ultimately the indication of a successful product. Ultimately sensory attributes drive product success (that is, repeat and continued purchase). However, ignoring the importance of extrinsic factors may neglect the vital product attributes responsible for the initial purchase, which may in turn, affect repeat purchase. The perception of sensory attributes assessed by DOL is mitigated by external perceptions of quality. If the sensory attributes do not deliver based upon the quality cues, the product will not be acceptable. Four key extrinsic factors that affect DOL are the perceived satiety, brand and labeling, price, and the emotional impact to decision making. In order to more thoroughly understand what the DOL for a product is, these 4 product cues should be considered in conjunction with sensory attribute perception to gain a holistic understanding of product acceptance. © 2015 Institute of Food Technologists®

  6. Extrinsic stretching narrowing and anterior indentation of the rectosigmoid junction

    International Nuclear Information System (INIS)

    Schulman, A.; Fataar, S.

    1979-01-01

    Thirty-five cases of extrinsic narrowing or anterior indentation of the rectosigmoid junction (RSJ) have been studied. The RSJ lies directly behind the pouch of Douglas which is a favoured site for peritoneal metastasis, abscess and endometriosis. Any space-occupying lesion of sufficient size at this site will indent the anterior aspects of the RSJ. Causes include distension or tumour of the ileum or sigmoid colon, gross ascites (when the patient is erect), and tumours below the pelvic peritonium, such as gynaecological neoplasm and internal iliac artery aneurysm. When a desmoplastic metastasis in the pouch of Douglas infiltrates the outer layers of the RSJ, the fibrosis produces an eccentric shortening on its anterior aspect, which in turn causes a pleating of the mucosa with the folds radiating towards the shortened area. This is also seen with primary pelvic carcinomas directly adherent to the rectum, endometriosis with repeated bleeding and increasing eccentric, submucosal fibrosis, and chronic abscess in the pouch of Douglas. Not all extrinsic narrowing of the RSJ are pathological. One case of anterior indentation followed operation for rectal prolapse. Ten additional cases showed narrowing due to a technical artefact air-distended colon rising into the upper abdomen to cause stretching at the RSJ. As with ascites, this narrowing due to 'high-rise sigmoid' disappeared when the patients became recumbent and the colonic air redistributed. (author)

  7. Efficient simulation of intrinsic, extrinsic and external noise in biochemical systems.

    Science.gov (United States)

    Pischel, Dennis; Sundmacher, Kai; Flassig, Robert J

    2017-07-15

    Biological cells operate in a noisy regime influenced by intrinsic, extrinsic and external noise, which leads to large differences of individual cell states. Stochastic effects must be taken into account to characterize biochemical kinetics accurately. Since the exact solution of the chemical master equation, which governs the underlying stochastic process, cannot be derived for most biochemical systems, approximate methods are used to obtain a solution. In this study, a method to efficiently simulate the various sources of noise simultaneously is proposed and benchmarked on several examples. The method relies on the combination of the sigma point approach to describe extrinsic and external variability and the τ -leaping algorithm to account for the stochasticity due to probabilistic reactions. The comparison of our method to extensive Monte Carlo calculations demonstrates an immense computational advantage while losing an acceptable amount of accuracy. Additionally, the application to parameter optimization problems in stochastic biochemical reaction networks is shown, which is rarely applied due to its huge computational burden. To give further insight, a MATLAB script is provided including the proposed method applied to a simple toy example of gene expression. MATLAB code is available at Bioinformatics online. flassig@mpi-magdeburg.mpg.de. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  8. Intrinsic – Extrinsic – Transcendent. A triarchic model of goal contents: introduction and validation

    Directory of Open Access Journals (Sweden)

    Małgorzata Ewa Górnik-Durose

    2017-04-01

    Full Text Available Background The article refers to an 11-factor circumplex model of goal contents introduced by Grouzet et al., which suggested a consistent structure of goals allocated within two dimensions: extrinsic–intrinsic and self-transcendent–physical. A previous study showed a rather poor fit of this model in a Polish context. Therefore using data from the aforementioned replication project in Study I we re-examined the structure and found a triarchic configuration more adequately fitting existing data. This new model was further tested in Study II. Participants and procedure To find an adequate factor structure of life goals measured by the Polish version of the Aspiration Index in Study I we ran exploratory and confirmatory factor analyses in three groups of 1,762 people in total. To check psychometric characteristics of the developed AI-23 questionnaire we conducted Study II on a group of 319 students. Results The analyses revealed a new structure of the Aspiration Index consisting of scales related to seven life goals connected with three general groups of goals: intrinsic, extrinsic and transcendent. Results of confirmatory factor analysis, convergent and divergent validation, internal consistency and test–retest reliability allowed AI-23 to be treated as an effective tool to measure life goals. Conclusions The results suggest a triarchic organization of goal contents, with self-transcendent goals supplementing well-established theoretical categories of intrinsic and extrinsic goals.

  9. Effect of Non Submerged Vanes on Separation Zone at Strongly-curved Channel Bends, a Laboratory Scale Study

    Directory of Open Access Journals (Sweden)

    Ali Akbar Akhtari

    2010-03-01

    Full Text Available Bends along open channels always pose difficulties for water transfer systems. One undesirable effect of bends in such channels, i.e. separation of water from inner banks, was studied. For the purposes of this study, the literature on the subject was first reviewed, and a strongly-curved open channel was designed and constructed on the laboratory scale. Several tests were performed to evaluate the accuracy of the lab model, data homogeneity, and systematic errors. The model was then calibrated and the influence of curvature on flow pattern past the curve was investigated. Also, for the first time, the influence of separation walls on flow pattern was investigated. Experimental results on three strongly-curved open channels with a curvature radius to channel width ratio of 1.5 and curvature angles of 30°, 60°, and 90° showed that, in all the cases studied, the effect of flow separation could be observed immediately after the curve. In addition, the greatest effect of flow separation was seen at a distance equal to channel width from the bend end. In the presence of middle walls and flow separation, the effect of water separation reduced at the bend, especially for a curvature of 90°.

  10. Dynamic high-resolution ultrasound of intrinsic and extrinsic ligaments of the wrist: How to make it simple

    International Nuclear Information System (INIS)

    Gitto, Salvatore; Messina, Carmelo; Mauri, Giovanni; Aliprandi, Alberto; Sardanelli, Francesco; Sconfienza, Luca Maria

    2017-01-01

    Highlights: • US allows for rapid, cost-effective, and non-invasive assessment of wrist ligaments. • Knowledge of landmarks and dynamic manoeuvres is basic for a systematic examination. • A sequential approach is effective, timesaving and feasible in clinical practice. - Abstract: Wrist ligaments are crucial structures for the maintenance of carpal stability. They are classified into extrinsic ligaments, connecting the carpus with the forearm bones or distal radioulnar ligaments, and intrinsic ligaments, entirely situated within the carpus. Lesions of intrinsic and extrinsic ligaments of the wrist have been demonstrated to occur largely, mostly in patients with history of trauma and carpal instability, or rheumatoid arthritis. Ultrasound allows for rapid, cost-effective, non-invasive and dynamic evaluation of the wrist, and may represent a valuable diagnostic tool. Although promising results have been published, ultrasound of wrist ligaments is not performed in routine clinical practice, maybe due to its technical feasibility regarded as quite complex. This review article aims to enlighten readers about the normal sonographic appearance of intrinsic and extrinsic carpal ligaments, and describe a systematic approach for their sonographic assessment with detailed anatomic landmarks, dynamic manoeuvres and scanning technique.

  11. Dynamic high-resolution ultrasound of intrinsic and extrinsic ligaments of the wrist: How to make it simple

    Energy Technology Data Exchange (ETDEWEB)

    Gitto, Salvatore, E-mail: sal.gitto@gmail.com [Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, Via Festa del Perdono 7, 20122 Milano (Italy); Messina, Carmelo [Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, Via Festa del Perdono 7, 20122 Milano (Italy); Mauri, Giovanni [Servizio di Radiologia, IRCCS Policlinico San Donato, Via Morandi 30, 20097 San Donato Milanese (Italy); Dipartimento di Radiologia Interventistica, Istituto Europeo di Oncologia, Via Ripamonti 435, 20141 Milano (Italy); Aliprandi, Alberto [Servizio di Radiologia, IRCCS Policlinico San Donato, Via Morandi 30, 20097 San Donato Milanese (Italy); Sardanelli, Francesco [Servizio di Radiologia, IRCCS Policlinico San Donato, Via Morandi 30, 20097 San Donato Milanese (Italy); Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Via Pascal 36, 20133 Milano (Italy); Sconfienza, Luca Maria [Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Via Pascal 36, 20133 Milano (Italy); Unità Operativa di Radiologia/Diagnostica per Immagini con Servizio di Radiologia Interventistica, IRCCS Istituto Ortopedico Galeazzi, Via Riccardo Galeazzi 4, 20161 Milano (Italy)

    2017-02-15

    Highlights: • US allows for rapid, cost-effective, and non-invasive assessment of wrist ligaments. • Knowledge of landmarks and dynamic manoeuvres is basic for a systematic examination. • A sequential approach is effective, timesaving and feasible in clinical practice. - Abstract: Wrist ligaments are crucial structures for the maintenance of carpal stability. They are classified into extrinsic ligaments, connecting the carpus with the forearm bones or distal radioulnar ligaments, and intrinsic ligaments, entirely situated within the carpus. Lesions of intrinsic and extrinsic ligaments of the wrist have been demonstrated to occur largely, mostly in patients with history of trauma and carpal instability, or rheumatoid arthritis. Ultrasound allows for rapid, cost-effective, non-invasive and dynamic evaluation of the wrist, and may represent a valuable diagnostic tool. Although promising results have been published, ultrasound of wrist ligaments is not performed in routine clinical practice, maybe due to its technical feasibility regarded as quite complex. This review article aims to enlighten readers about the normal sonographic appearance of intrinsic and extrinsic carpal ligaments, and describe a systematic approach for their sonographic assessment with detailed anatomic landmarks, dynamic manoeuvres and scanning technique.

  12. Poncirin Induces Apoptosis in AGS Human Gastric Cancer Cells through Extrinsic Apoptotic Pathway by up-Regulation of Fas Ligand

    Directory of Open Access Journals (Sweden)

    Venu Venkatarame Gowda Saralamma

    2015-09-01

    Full Text Available Poncirin, a natural bitter flavanone glycoside abundantly present in many species of citrus fruits, has various biological benefits such as anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer activities. The anti-cancer mechanism of Poncirin remains elusive to date. In this study, we investigated the anti-cancer effects of Poncirin in AGS human gastric cancer cells (gastric adenocarcinoma. The results revealed that Poncirin could inhibit the proliferation of AGS cells in a dose-dependent manner. It was observed Poncirin induced accumulation of sub-G1 DNA content, apoptotic cell population, apoptotic bodies, chromatin condensation, and DNA fragmentation in a dose-dependent manner in AGS cells. The expression of Fas Ligand (FasL protein was up-regulated dose dependently in Poncirin-treated AGS cells Moreover, Poncirin in AGS cells induced activation of Caspase-8 and -3, and subsequent cleavage of poly(ADP-ribose polymerase (PARP. Inhibitor studies’ results confirm that the induction of caspase-dependent apoptotic cell death in Poncirin-treated AGS cells was led by the Fas death receptor. Interestingly, Poncirin did not show any effect on mitochondrial membrane potential (ΔΨm, pro-apoptotic proteins (Bax and Bak and anti-apoptotic protein (Bcl-xL in AGS-treated cells followed by no activation in the mitochondrial apoptotic protein caspase-9. This result suggests that the mitochondrial-mediated pathway is not involved in Poncirin-induced cell death in gastric cancer. These findings suggest that Poncirin has a potential anti-cancer effect via extrinsic pathway-mediated apoptosis, possibly making it a strong therapeutic agent for human gastric cancer.

  13. Text Summarization Evaluation: Correlating Human Performance on an Extrinsic Task with Automatic Intrinsic Metrics

    National Research Council Canada - National Science Library

    President, Stacy F; Dorr, Bonnie J

    2006-01-01

    This research describes two types of summarization evaluation methods, intrinsic and extrinsic, and concentrates on determining the level of correlation between automatic intrinsic methods and human...

  14. The social costs of extrinsic relative to intrinsic goal pursuits: their relation with social dominance and racial and ethnic prejudice.

    Science.gov (United States)

    Duriez, Bart; Vansteenkiste, Maarten; Soenens, Bart; De Witte, Hans

    2007-08-01

    Self-determination theory's distinction between extrinsic and intrinsic goal pursuits offers a possible explanation for ethnic and racial prejudice. Because extrinsic relative to intrinsic goal pursuits (E/I) stimulate interpersonal competition, they were expected to predict social dominance orientation (SDO), which, in turn, would predict racial and ethnic prejudice. Results of a first cross-sectional study showed that E/I goal pursuits are positively associated with prejudice and that SDO partially mediates this association. In a second longitudinal study, we replicated these results. In addition, however, we found evidence for a reciprocal relationship between E/I goal pursuit and SDO. Moreover, both E/I goal pursuit and SDO had an independent effect on increases in prejudice. Implications of these findings are discussed.

  15. The influence that Albanian parents extrinsic versus intrinsic goal promotion has on the increase of adolescents’ prejudice

    Directory of Open Access Journals (Sweden)

    Mimoza Çarka

    2015-07-01

    Full Text Available The aim of this article and more precisely of the research is to examine the emphasis parents put on extrinsic or intrinsic goal promotion during childrearing. Further more in the following article is, as well, examined the co-relation between the above E/I goal promotion with the increased racial prejudice. the above effect is accounted for by adolescents’ RWA (right-wing authoritarianism and SDO (social dominance orientation levels, which, in turn represent two individual difference dimensions identified as independent predictors of prejudice. To fulfill the research we have focused on high school students’ parents and we have asked them to complete a questionnaire. the study confirmed what we really feared that both maternal and paternal questionnaires put a great importance on the promotion of extrinsic versus intrinsic goals, generalizing the fact that we are raising materialistic children.

  16. Finite-size effect of η-deformed AdS5×S5 at strong coupling

    Directory of Open Access Journals (Sweden)

    Changrim Ahn

    2017-04-01

    Full Text Available We compute Lüscher corrections for a giant magnon in the η-deformed (AdS5×S5η using the su(2|2q-invariant S-matrix at strong coupling and compare with the finite-size effect of the corresponding string state, derived previously. We find that these two results match and confirm that the su(2|2q-invariant S-matrix is describing world-sheet excitations of the η-deformed background.

  17. Finite-size effect of η-deformed AdS5 × S5 at strong coupling

    Science.gov (United States)

    Ahn, Changrim

    2017-04-01

    We compute Lüscher corrections for a giant magnon in the η-deformed (AdS5×S5)η using the su(2 | 2) q-invariant S-matrix at strong coupling and compare with the finite-size effect of the corresponding string state, derived previously. We find that these two results match and confirm that the su(2 | 2) q-invariant S-matrix is describing world-sheet excitations of the η-deformed background.

  18. Strong diffusion effect of charm quarks on J/ψ production in Pb-Pb collisions at the LHC

    Science.gov (United States)

    Zhao, Jiaxing; Chen, Baoyi

    2018-01-01

    We study the J / ψ production based on coalescence model at √{sNN } = 2.76 and 5.02 TeV Pb-Pb collisions. With the colliding energy increasing from 2.76 TeV to 5.02 TeV, the number of charm pairs is enhanced by more than 50%. However, the ratio of J / ψ inclusive nuclear modification factors RAA5.02 TeV / RAA2.76 TeV is only about 1.1 ∼ 1.2. We find that the regeneration of J / ψ is proportional to the densities of charm and anti-charm quarks, instead of their total numbers. The charm quark density is diluted by the strong expansion of quark gluon plasma, which suppresses the combination probability of heavy quarks and J / ψ regeneration. This effect is more important in higher colliding energies where QGP expansion is strong. We also propose the ratio NJ/ψ /(Nc) 2 as a measurement of c and c bar coalescence probability, which is only affected by the heavy quark diffusions in QGP, and does not depend on the inputs such as cold nuclear matter effects and cross sections of charm quark production. Further more, we give the predictions at the energy of Future Circular Collider (√{sNN } = 39 TeV).

  19. Strong and Nonspecific Synergistic Antibacterial Efficiency of Antibiotics Combined with Silver Nanoparticles at Very Low Concentrations Showing No Cytotoxic Effect.

    Science.gov (United States)

    Panáček, Aleš; Smékalová, Monika; Kilianová, Martina; Prucek, Robert; Bogdanová, Kateřina; Večeřová, Renata; Kolář, Milan; Havrdová, Markéta; Płaza, Grażyna Anna; Chojniak, Joanna; Zbořil, Radek; Kvítek, Libor

    2015-12-28

    The resistance of bacteria towards traditional antibiotics currently constitutes one of the most important health care issues with serious negative impacts in practice. Overcoming this issue can be achieved by using antibacterial agents with multimode antibacterial action. Silver nano-particles (AgNPs) are one of the well-known antibacterial substances showing such multimode antibacterial action. Therefore, AgNPs are suitable candidates for use in combinations with traditional antibiotics in order to improve their antibacterial action. In this work, a systematic study quantifying the synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus was performed. Employing the microdilution method as more suitable and reliable than the disc diffusion method, strong synergistic effects were shown for all tested antibiotics combined with AgNPs at very low concentrations of both antibiotics and AgNPs. No trends were observed for synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs, indicating non-specific synergistic effects. Moreover, a very low amount of silver is needed for effective antibacterial action of the antibiotics, which represents an important finding for potential medical applications due to the negligible cytotoxic effect of AgNPs towards human cells at these concentration levels.

  20. Strong and Nonspecific Synergistic Antibacterial Efficiency of Antibiotics Combined with Silver Nanoparticles at Very Low Concentrations Showing No Cytotoxic Effect

    Directory of Open Access Journals (Sweden)

    Aleš Panáček

    2015-12-01

    Full Text Available The resistance of bacteria towards traditional antibiotics currently constitutes one of the most important health care issues with serious negative impacts in practice. Overcoming this issue can be achieved by using antibacterial agents with multimode antibacterial action. Silver nano-particles (AgNPs are one of the well-known antibacterial substances showing such multimode antibacterial action. Therefore, AgNPs are suitable candidates for use in combinations with traditional antibiotics in order to improve their antibacterial action. In this work, a systematic study quantifying the synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus was performed. Employing the microdilution method as more suitable and reliable than the disc diffusion method, strong synergistic effects were shown for all tested antibiotics combined with AgNPs at very low concentrations of both antibiotics and AgNPs. No trends were observed for synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs, indicating non-specific synergistic effects. Moreover, a very low amount of silver is needed for effective antibacterial action of the antibiotics, which represents an important finding for potential medical applications due to the negligible cytotoxic effect of AgNPs towards human cells at these concentration levels.

  1. Novel siRNA delivery system using a ternary polymer complex with strong silencing effect and no cytotoxicity.

    Science.gov (United States)

    Kodama, Yukinobu; Shiokawa, Yumi; Nakamura, Tadahiro; Kurosaki, Tomoaki; Aki, Keisei; Nakagawa, Hiroo; Muro, Takahiro; Kitahara, Takashi; Higuchi, Norihide; Sasaki, Hitoshi

    2014-01-01

    We developed a novel small interfering RNA (siRNA) delivery system using a ternary complex with polyethyleneimine (PEI) and γ-polyglutamic acid (γ-PGA), which showed silencing effect and no cytotoxicity. The binary complexes of siRNA with PEI were approximately 73-102 nm in particle size and 45-52 mV in ζ-potential. The silencing effect of siRNA/PEI complexes increased with an increase of PEI, and siRNA/PEI complexes with a charge ratio greater than 16 showed significant luciferase knockdown in a mouse colon carcinoma cell line regularly expressing luciferase (Colon26/Luc cells). However, strong cytotoxicity and blood agglutination were observed in the siRNA/Lipofectamine complex and siRNA/PEI16 complex. Recharging cationic complexes with an anionic compound was reported to be a promising method for overcoming these toxicities. We therefore prepared ternary complexes of siRNA with PEI (charge ratio 16) by the addition of γ-PGA to reduce cytotoxicity and deliver siRNA. As expected, the cytotoxicity of the ternary complexes decreased with an increase of γ-PGA content, which decreased the ζ-potential of the complexes. A strong silencing effect comparable to siRNA/Lipofectamine complex was discovered in ternary complexes including γ-PGA with an anionic surface charge. The high incorporation of ternary complexes into Colon26/Luc cells was confirmed with fluorescence microcopy. Having achieved knockdown of an exogenously transfected gene, the ability of the complex to mediate knockdown of an endogenous housekeeping gene, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), was assessed in B16-F10 cells. The ternary complex (siRNA/PEI16/γ-PGA12 complex) exhibited a significant GAPDH knockdown effect. Thus, we developed a useful siRNA delivery system.

  2. Extrinsic factors affecting accuracy of ultrasonic flowmeters for LMFBRs

    International Nuclear Information System (INIS)

    Managan, W.W.

    1976-08-01

    Assuming that ultrasonic flowmeters of suitable intrinsic accuracy are feasible, this report explores factors extrinsic to the flowmeter which affect the accuracy such as asymmetric flow profile, regions of high turbulence and thermal stratification. By integrating isovelocity flow profile maps, the predicted performance of various flowmeter configurations may be compared to experimental data. For the two pipe arrangements analyzed, the single diametral path flowmeter results were within 5 percent of true flow rate. Theoretical correction factors could reduce the error for the straight pipe but increased the error for asymmetrical flow. On the same pipe arrangements a four path ultrasonic flowmeter spaced for Gaussian integration gave less than 1 percent error. For more general conclusions a range of flow profiles produced by typical LMFBR piping arrangements must be analyzed

  3. Comparison of exit time moment spectra for extrinsic metric balls

    DEFF Research Database (Denmark)

    Hurtado, Ana; Markvorsen, Steen; Palmer, Vicente

    2012-01-01

    We prove explicit upper and lower bounds for the $L^1$-moment spectra for the Brownian motion exit time from extrinsic metric balls of submanifolds $P^m$ in ambient Riemannian spaces $N^n$. We assume that $P$ and $N$ both have controlled radial curvatures (mean curvature and sectional curvature......, respectively) as viewed from a pole in $N$. The bounds for the exit moment spectra are given in terms of the corresponding spectra for geodesic metric balls in suitably warped product model spaces. The bounds are sharp in the sense that equalities are obtained in characteristic cases. As a corollary we also...... obtain new intrinsic comparison results for the exit time spectra for metric balls in the ambient manifolds $N^n$ themselves....

  4. Covariant extrinsic gravity and the geometric origin of dark energy

    Science.gov (United States)

    Jalalzadeh, S.; Rostami, T.

    2015-01-01

    In this paper, we construct the covariant or model independent induced Einstein-Yang-Mills field equations on a four-dimensional brane embedded isometrically in an D-dimensional bulk space, assuming the matter fields are confined to the brane. Applying this formalism to cosmology, we derive the generalized Friedmann equations. We derive the density parameter of dark energy in terms of width of the brane, normal curvature radii and the number of extra large dimensions. We show that dark energy could actually be the manifestation of the local extrinsic shape of the brane. It is shown that the predictions of this model are in good agreement with observation if we consider an 11-dimensional bulk space.

  5. Extrinsic gate capacitance compact model for UTBB MOSFETs

    Science.gov (United States)

    Martinez-Lopez, Andrea G.; Tinoco, Julio C.; Lezama, Gamaliel; Conde, Jorge E.; Kazemi Esfeh, Babak; Raskin, Jean-Pierre

    2018-01-01

    Ultra-thin body and buried oxide transistors have gained attention as candidates for near future CMOS technology nodes. Recent studies have pointed out that the total parasitic gate capacitance becomes an important concern for very-high frequency performance. In this paper a semi-analytical model to describe the total extrinsic gate capacitance for ultrathin silicon body and buried oxide transistors is presented. The developed model considers the main technological parameters and has been verified by finite-element numerical simulations as well as by comparison with experimental measurements. The relative weight of the main parasitic components is addressed as well as their impact over the current gain cut-off frequency. Finally, the possibility to improve the cut-off frequency by about 35% due to the reduction of the parasitic gate capacitance is highlighted.

  6. Magnetotransport properties of Cr1−δTe thin films with strong perpendicular magnetic anisotropy

    Directory of Open Access Journals (Sweden)

    L. Zhou

    2017-12-01

    Full Text Available P-type ferromagnetic Cr1-δTe thin films with the Curie temperature of 170K were epitaxially grown on GaAs substrate. Low-temperature magnetotransport study reveals that the film has a strong perpendicular magnetic anisotropy (PMA and an anisotropic magnetoresistance (AMR ratio up to 8.1%. Furthermore, reduced anomalous Hall effect is observed at low temperatures in Cr1-δTe, suggesting the possible crossover of the contribution to AHE from the intrinsic mechanism to extrinsic skew scattering. Distinctive from conventional transition metal ferromagnets, the AMR ratio is also greatly suppressed at low temperatures. Our work demonstrates that epitaxial Cr1-δTe films are interesting platforms for studying the physics underlying the strong PMA and large AMR.

  7. Extrinsic functions of lectin domains in O-N-acetylgalactosamine glycan biosynthesis

    DEFF Research Database (Denmark)

    Lorenz, Virginia; Ditamo, Yanina; Cejas, Romina B

    2016-01-01

    Glycan biosynthesis occurs mainly in Golgi. Molecular organization and functional regulation of this process are not well understood. We evaluated the extrinsic effect of lectin domains (β-trefoil fold) of polypeptide GalNAc-transferases (ppGalNAc-Ts) on catalytic activity of glycosyltransferases...... during O-GalNAc glycan biosynthesis. The presence of lectin domain T3lec or T4lec during ppGalNAc-T2 and ppGalNAc-T3 catalytic reaction had a clear inhibitory effect on GalNAc-T activity. Interaction of T3lec or T4lec with ppGalNAc-T2 catalytic domain was not mediated by carbohydrate. T3lec, but not T2...

  8. Fit and Strong! Plus: design of a comparative effectiveness evaluation of a weight management program for older adults with osteoarthritis.

    Science.gov (United States)

    Smith-Ray, Renae L; Fitzgibbon, Marian L; Tussing-Humphreys, Lisa; Schiffer, Linda; Shah, Amy; Huber, Gail M; Braunschweig, Carol; Campbell, Richard T; Hughes, Susan L

    2014-03-01

    Osteoarthritis (OA) is the most common chronic condition and principal cause of disability among older adults. The current obesity epidemic has contributed to this high prevalence rate. Fortunately both OA symptoms and obesity can be ameliorated through lifestyle modifications. Physical activity (PA) combined with weight management improves physical function among obese persons with knee OA but evidence-based interventions that combine PA and weight management are limited for this population. This paper describes a comparative effectiveness trial testing an evidence-based PA program for adults with lower extremity (LE) OA, Fit and Strong!, against an enhanced version that also addresses weight management based on the evidence-based Obesity Reduction Black Intervention Trial (ORBIT). Adult participants (n=400) with LE OA, age 60+, overweight/obese, and not meeting PA requirements of ≥ 150 min per week, are randomized to one of the two programs. Both 8-week interventions meet 3 times per week and include 60 min of strength, flexibility, and aerobic exercise instruction followed by 30 min of education/group discussion. The Fit and Strong! education sessions focus on using PA to manage OA; whereas Fit and Strong! Plus addresses PA and weight loss management strategies. Maintenance of behavior change is reinforced in both groups during months 3-24 through telephone calls and mailed newsletters. Outcomes are assessed at baseline, and 2, 6, 12, 18, and 24 months. Primary outcomes are dietary change at 2 months followed by weight loss at 6 months that is maintained at 24 months. Secondary outcomes assess PA, physical performance, and anxiety/depression. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Intrinsic and Extrinsic School Motivation as a Function of Age: The Mediating Role of Autonomy Support

    Science.gov (United States)

    Gillet, Nicolas; Vallerand, Robert J.; Lafreniere, Marc-Andre K.

    2012-01-01

    The main purpose of the present research was to investigate school intrinsic and extrinsic motivation, and amotivation as a function of age in a sample of 1,600 elementary and high school students aged 9-17 years. First, results revealed a systematic decrease in intrinsic motivation and self-determined extrinsic motivation from age 9 to 12 years,…

  10. Do people differentiate between intrinsic and extrinsic goals for physical activity?

    Science.gov (United States)

    McLachlan, Sarah; Hagger, Martin S

    2011-04-01

    The distinction between intrinsic and extrinsic goals, and between goal pursuit for intrinsically and extrinsically motivated reasons, is a central premise of self-determination theory. Proponents of the theory have proposed that the pursuit of intrinsic goals and intrinsically motivated goal striving each predict adaptive psychological and behavioral outcomes relative to the pursuit of extrinsic goals and extrinsically motivated goal striving. Despite evidence to support these predictions, research has not explored whether individuals naturally differentiate between intrinsic and extrinsic goals. Two studies tested whether people make this differentiation when recalling goals for leisure-time physical activity. Using memory-recall methods, participants in Study 1 were asked to freely generate physical activity goals. A subsample (N = 43) was asked to code their freely generated goals as intrinsic or extrinsic. In Study 2, participants were asked to recall intrinsic and extrinsic goals after making a decision regarding their future physical activity. Results of these studies revealed that individuals' goal generation and recall exhibited significant clustering by goal type. Participants encountered some difficulties when explicitly coding goals. Findings support self-determination theory and indicate that individuals discriminate between intrinsic and extrinsic goals.

  11. Creating Rich Portraits: A Mixed-Methods Approach to Understanding Profiles of Intrinsic and Extrinsic Motivations

    Science.gov (United States)

    Corpus, Jennifer Henderlong; Wormington, Stephanie V.; Haimovitz, Kyla

    2016-01-01

    A person-centered, mixed-methods approach (self-report surveys, semistructured interviews, school records) was used to characterize and evaluate profiles of intrinsic and extrinsic motivations among 243 third- through eighth-grade students. Cluster analysis suggested four distinct profiles: high quantity (high intrinsic, high extrinsic), primarily…

  12. The Role of Extrinsic Feedback in Interlanguage Fossilization: A Discussion of "Rule Fossilization: A Tentative Model."

    Science.gov (United States)

    Lamendella, John T.; Selinker, Larry

    1979-01-01

    Six tentative conclusions about the role of extrinsic feedback in interlanguage fossilization are presented and discussed in light of hypotheses made by Virgil and Oller regarding this phenomenon. Extrinsic factors are those characteristics of the learner which are oriented toward the environment and which act as the interface between the learner…

  13. Extrinsic Motivators Affecting Fourth-Grade Students' Interest and Enrollment in an Instrumental Music Program

    Science.gov (United States)

    Vasil, Martina

    2013-01-01

    The purpose of this study was to investigate fourth-grade students' extrinsic motivators for joining and continuing in a school instrumental music program. Three research questions were investigated: (a) What extrinsic motivators have influenced fourth-grade students' initial interest and continuing participation in an instrumental music program?…

  14. Intrinsic, Extrinsic, and Integrative Orientations of French Canadian Learners of English.

    Science.gov (United States)

    Noels, Kimberly A.; Clement, Richard; Pelletier, Luc G.

    2001-01-01

    Replicates previous research on intrinsic and extrinsic motivation for language learning in French Canadian students of English and considers the relations between intrinsic and extrinsic motivation and integrative orientation. Quebecois university students completed a questionnaire addressing their reasons for learning English. (Author/VWL)

  15. The Relationship between Counselor Satisfaction and Extrinsic Job Factors in State Rehabilitation Agencies.

    Science.gov (United States)

    Andrew, Jason D.; Faubion, Clayton W.; Palmer, Charles D.

    2002-01-01

    Researchers collected survey data from 315 state rehabilitation agency counselors in 16 states to examine job satisfaction and extrinsic job factors. This report provides statistical analyses and extensive descriptive data characteristics. Counselor job satisfaction correlated significantly with six extrinsic job factors, and gender differences…

  16. [Effects of post-anthesis irrigation frequency on the grain quality of strong gluten winter wheat cultivars].

    Science.gov (United States)

    Yao, Feng-juan; He, Ming-rong; Li, Fei; Xu, Liang-liang; Huang, Chuan-hua; Qu, Mu

    2008-12-01

    In order to investigate the effects of post-anthesis irrigation frequency on the grain quality of strong gluten winter wheat, two cultivars Jimai 20 and Gaocheng 8901 were subjected to a series of irrigation frequencies under rainfall proof conditions, with their grain yield and grain quality (farinograph parameters and loaf volume) and protein composition evaluated. The results indicated that with increasing irrigation frequency, the grain yield of the two cultivars, their wheat flour dough development time, dough stability time, and loaf volume were noted to be increased first but decreased then. The grain yield and quality of Gaocheng 8901 were the highest when irrigated once after anthesis, while those of Jimai 20 were the best when irrigated twice after anthesis, respectively. The contents of monomeric protein, soluble glutenin, insoluble glutenin, total glutenin, flour protein, and wet gluten in the grains displayed the similar trends. Stepwise regression analysis showed that under the test post-anthesis irrigation frequencies, the key factor affecting dough stability time was insoluble glutenin content, and loaf volume was significantly correlated with total glutenin content. It was suggested that to maintain the quality stability of high grade strong gluten winter wheat, irrigation management should take the improvement of grain protein composition, and glutenin in particular, as the target.

  17. Psychobehavioural Factors Are More Strongly Associated with Successful Weight Management Than Predetermined Satiety Effect or Other Characteristics of Diet

    Directory of Open Access Journals (Sweden)

    Leila Karhunen

    2012-01-01

    Full Text Available This study aimed to investigate factors associated with weight management, especially whether satiety value of food as a part of a weight-maintenance diet would affect self-regulation of food intake and weight management. Altogether 82 obese subjects completed the study consisting of weight-loss and weight-maintenance (WM periods. During the WM, subjects were randomized into higher- and lower-satiety food groups. No differences were observed in the changes in body weight, energy intake, or eating behaviour between the groups, even despite the different macronutrient compositions of the diets. However, when regarding all study subjects, success in WM was most strongly associated with a greater increase in the flexible control of eating and experience of greater easiness of WM and control of food intake and a greater decrease in uncontrollable eating and psychological distress. Psychobehavioural factors seem to be more strongly associated with successful weight management than the predetermined satiety effect or other characteristics of the diet.

  18. A device to measure the effects of strong magnetic fields on the image resolution of PET scanners

    CERN Document Server

    Burdette, D; Chesi, E; Clinthorne, N H; Cochran, E; Honscheid, K; Huh, S S; Kagan, H; Knopp, M; Lacasta, C; Mikuz, M; Schmalbrock, P; Studen, A; Weilhammer, P

    2009-01-01

    Very high resolution images can be achieved in small animal PET systems utilizing solid state silicon pad detectors. As these systems approach sub-millimeter resolutions, the range of the positron is becoming the dominant contribution to image blur. The size of the positron range effect depends on the initial positron energy and hence the radioactive tracer used. For higher energy positron emitters, such as and , which are gaining importance in small animal studies, the width of the annihilation point distribution dominates the spatial resolution. This positron range effect can be reduced by embedding the field of view of the PET scanner in a strong magnetic field. In order to confirm this effect experimentally, we developed a high resolution PET instrument based on silicon pad detectors that can operate in a 7 T magnetic field. In this paper, we describe the instrument and present initial results of a study of the effects of magnetic fields up to 7 T on PET image resolution for and point sources.

  19. Integrated Theory of Planned Behavior with Extrinsic Motivation to Predict Intention Not to Use Illicit Drugs by Fifth-Grade Students in Taiwan

    Science.gov (United States)

    Liao, Jung-Yu; Chang, Li-Chun; Hsu, Hsiao-Pei; Huang, Chiu-Mieh; Huang, Su-Fei; Guo, Jong-Long

    2017-01-01

    This study assessed the effects of a model that integrated the theory of planned behavior (TPB) with extrinsic motivation (EM) in predicting the intentions of fifth-grade students to not use illicit drugs. A cluster-sampling design was adopted in a cross-sectional survey (N = 571). The structural equation modeling results showed that the model…

  20. Colonization of a territory by a stochastic population under a strong Allee effect and a low immigration pressure.

    Science.gov (United States)

    Be'er, Shay; Assaf, Michael; Meerson, Baruch

    2015-06-01

    We study the dynamics of colonization of a territory by a stochastic population at low immigration pressure. We assume a sufficiently strong Allee effect that introduces, in deterministic theory, a large critical population size for colonization. At low immigration rates, the average precolonization population size is small, thus invalidating the WKB approximation to the master equation. We circumvent this difficulty by deriving an exact zero-flux solution of the master equation and matching it with an approximate nonzero-flux solution of the pertinent Fokker-Planck equation in a small region around the critical population size. This procedure provides an accurate evaluation of the quasistationary probability distribution of population sizes in the precolonization state and of the mean time to colonization, for a wide range of immigration rates. At sufficiently high immigration rates our results agree with WKB results obtained previously. At low immigration rates the results can be very different.

  1. Colonization of a territory by a stochastic population under a strong Allee effect and a low immigration pressure

    Science.gov (United States)

    Be'er, Shay; Assaf, Michael; Meerson, Baruch

    2015-06-01

    We study the dynamics of colonization of a territory by a stochastic population at low immigration pressure. We assume a sufficiently strong Allee effect that introduces, in deterministic theory, a large critical population size for colonization. At low immigration rates, the average precolonization population size is small, thus invalidating the WKB approximation to the master equation. We circumvent this difficulty by deriving an exact zero-flux solution of the master equation and matching it with an approximate nonzero-flux solution of the pertinent Fokker-Planck equation in a small region around the critical population size. This procedure provides an accurate evaluation of the quasistationary probability distribution of population sizes in the precolonization state and of the mean time to colonization, for a wide range of immigration rates. At sufficiently high immigration rates our results agree with WKB results obtained previously. At low immigration rates the results can be very different.

  2. Strong spin-filtering and spin-valve effects in a molecular V–C60–V contact

    Directory of Open Access Journals (Sweden)

    Mohammad Koleini

    2012-08-01

    Full Text Available Motivated by the recent achievements in the manipulation of C60 molecules in STM experiments, we study theoretically the structure and electronic properties of a C60 molecule in an STM tunneljunction with a magnetic tip and magnetic adatom on a Cu(111 surface using first-principles calculations. For the case of a vanadium tip/adatom, we demonstrate how spin coupling between the magnetic V atoms, mediated by the C60, can be observed in the electronic transport, which display a strong spin-filtering effect, allowing mainly majority-spin electrons to pass (>95%. Moreover, we find a significant change in the conductance between parallel and anti-parallel spin polarizations in the junction (86% which suggests that STM experiments should be able to characterize the magnetism and spin coupling for these systems.

  3. Noise-induced extinction for a ratio-dependent predator-prey model with strong Allee effect in prey

    Science.gov (United States)

    Mandal, Partha Sarathi

    2018-04-01

    In this paper, we study a stochastically forced ratio-dependent predator-prey model with strong Allee effect in prey population. In the deterministic case, we show that the model exhibits the stable interior equilibrium point or limit cycle corresponding to the co-existence of both species. We investigate a probabilistic mechanism of the noise-induced extinction in a zone of stable interior equilibrium point. Computational methods based on the stochastic sensitivity function technique are applied for the analysis of the dispersion of random states near stable interior equilibrium point. This method allows to construct a confidence domain and estimate the threshold value of the noise intensity for a transition from the coexistence to the extinction.

  4. Field emission properties and strong localization effect in conduction mechanism of nanostructured perovskite LaNiO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Kamble, Ramesh B., E-mail: rbk.physics@coep.ac.in [Department of Physics, Indian Institute of Science, Bangalore 560012, Karnataka (India); Department of Physics, College of Engineering, Pune 411005, Maharashtra (India); Tanty, Narendra; Patra, Ananya; Prasad, V. [Department of Physics, Indian Institute of Science, Bangalore 560012, Karnataka (India)

    2016-08-22

    We report the potential field emission of highly conducting metallic perovskite lanthanum nickelate (LaNiO{sub 3}) from the nanostructured pyramidal and whisker shaped tips as electron emitters. Nano particles of lanthanum nickelate (LNO) were prepared by sol-gel route. Structural and morphological studies have been carried out. Field emission of LNO exhibited high emission current density, J = 3.37 mA/cm{sup 2} at a low threshold electric field, E{sub th} = 16.91 V/μm, obeying Fowler–Nordheim tunneling. The DC electrical resistivity exhibited upturn at 11.6 K indicating localization of electron at low temperature. Magnetoresistance measurement at different temperatures confirmed strong localization in nanostructured LNO obeying Anderson localization effect at low temperature.

  5. Strong Photonic-Band-Gap Effect on the Spontaneous Emission in 3D Lead Halide Perovskite Photonic Crystals.

    Science.gov (United States)

    Zhou, Xue; Li, Mingzhu; Wang, Kang; Li, Huizeng; Li, Yanan; Li, Chang; Yan, Yongli; Zhao, Yongsheng; Song, Yanlin

    2018-03-25

    Stimulated emission in perovskite-embedded polymer opal structures is investigated. A polymer opal structure is filled with a perovskite, and perovskite photonic crystals are prepared. The spontaneous emission of the perovskite embedded in the polymer opal structures exhibits clear signatures of amplified spontaneous emission (ASE) via gain modulation. The difference in refractive-index contrast between the perovskite and the polymer opal is large enough for retaining photonic-crystals properties. The photonic band gap has a strong effect on the fluorescence emission intensity and lifetime. The stimulated emission spectrum exhibits a narrow ASE rather than a wide fluorescence peak in the thin film. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Psychobehavioural Factors Are More Strongly Associated with Successful Weight Management Than Predetermined Satiety Effect or Other Characteristics of Diet

    DEFF Research Database (Denmark)

    Karhunen, Leila; Lyly, Marika; Lapveteläinen, Anja

    2012-01-01

    This study aimed to investigate factors associated with weight management, especially whether satiety value of food as a part of a weight-maintenance diet would affect self-regulation of food intake and weight management. Altogether 82 obese subjects completed the study consisting of weight...... factors seem to be more strongly associated with successful weight management than the predetermined satiety effect or other characteristics of the diet.......-loss and weight-maintenance (WM) periods. During theWM, subjects were randomized into higher- and lower-satiety food groups. No differences were observed in the changes in body weight, energy intake, or eating behaviour between the groups, even despite the different macronutrient compositions of the diets...

  7. Strong spin-filtering and spin-valve effects in a molecular V-C-60-V contact

    DEFF Research Database (Denmark)

    Koleini, Mohammad; Brandbyge, Mads

    2012-01-01

    Motivated by the recent achievements in the manipulation of C-60 molecules in STM experiments, we study theoretically the structure and electronic properties of a C-60 molecule in an STM tunneljunction with a magnetic tip and magnetic adatom on a Cu(111) surface using first-principles calculations....... For the case of a vanadium tip/adatom, we demonstrate how spin coupling between the magnetic V atoms, mediated by the C-60, can be observed in the electronic transport, which display a strong spin-filtering effect, allowing mainly majority-spin electrons to pass (>95%). Moreover, we find a significant change...... in the conductance between parallel and anti-parallel spin polarizations in the junction (86%) which suggests that STM experiments should be able to characterize the magnetism and spin coupling for these systems....

  8. Compressibility effects on a shear flow in strongly coupled dusty plasma. I. A study using computational fluid dynamics

    Science.gov (United States)

    Gupta, Akanksha; Ganesh, Rajaraman

    2018-01-01

    We study compressibility effects on the two-dimensional strongly coupled dusty plasma by means of computational fluid dynamics (CFD) with the Kolmogorov flow as an initial shear flow profile. Nonlinear compressible vortex flow dynamics and other linear and nonlinear properties of such flow in the presence of variable density, pressure, and electrostatic potential are addressed using a generalised compressible hydrodynamic model. The stabilizing effect of compressibility on the unstable shear flows in the presence of strong correlation ( τm>0 ) is presented. Increasing the Mach number relatively reduces the growth-rate of perturbation. On the other hand, strong correlation makes the medium to be more unstable and increases the growth rate. Using an eigen value solver, various linear properties of compressible Kolmogorov flow have been investigated for a range of variable parameters, for example, Mach number, Reynolds number, and viscoelastic coefficient (τm). Compressible Kolmogorov flow becomes unstable above a critical value of the Reynolds number (Rc), and below Rc, the shear flow is found to be neutrally stable. In this study, it is found that the viscoelasticity reduces the value of Rc. For our choice of parameters, at τm=τmc , the compressible Kolmogorov flow becomes unconditionally unstable and no Rc exists for values of τm higher than τmc . To address the nonlinear properties, for example, mode-mode interaction due to the presence of nonlinearity in the fluid, vortex formation, etc., a massively parallelized Advanced Generalized SPECTral Code (AG-Spect) has been developed. AG-Spect, a newly developed code, is an efficient tool to solve any set of nonlinear fluid dynamic equations. A good agreement in linear growth rates obtained from the eigen value solver and time dependent simulation (AG-Spect) is found. In our CFD study, the suppression of instability, elongated vortex structures, pattern formation, nonlinear saturation, and visco

  9. Extrinsic Factors Involved in the Differentiation of Stem Cells into Insulin-Producing Cells: An Overview

    Directory of Open Access Journals (Sweden)

    Rebecca S. Y. Wong

    2011-01-01

    Full Text Available Diabetes mellitus is a chronic disease with many debilitating complications. Treatment of diabetes mellitus mainly revolves around conventional oral hypoglycaemic agents and insulin replacement therapy. Recently, scientists have turned their attention to the generation of insulin-producing cells (IPCs from stem cells of various sources. To date, many types of stem cells of human and animal origins have been successfully turned into IPCs in vitro and have been shown to exert glucose-lowering effect in vivo. However, scientists are still faced with the challenge of producing a sufficient number of IPCs that can in turn produce sufficient insulin for clinical use. A careful choice of stem cells, methods, and extrinsic factors for induction may all be contributing factors to successful production of functional beta-islet like IPCs. It is also important that the mechanism of differentiation and mechanism by which IPCs correct hyperglycaemia are carefully studied before they are used in human subjects.

  10. An international survey to identify the intrinsic and extrinsic factors of research studies most likely to change orthopaedic practice.

    Science.gov (United States)

    Thornley, P; de Sa, D; Evaniew, N; Farrokhyar, F; Bhandari, M; Ghert, M

    2016-04-01

    Evidence -based medicine (EBM) is designed to inform clinical decision-making within all medical specialties, including orthopaedic surgery. We recently published a pilot survey of the Canadian Orthopaedic Association (COA) membership and demonstrated that the adoption of EBM principles is variable among Canadian orthopaedic surgeons. The objective of this study was to conduct a broader international survey of orthopaedic surgeons to identify characteristics of research studies perceived as being most influential in informing clinical decision-making. A 29-question electronic survey was distributed to the readership of an established orthopaedic journal with international readership. The survey aimed to analyse the influence of both extrinsic (journal quality, investigator profiles, etc.) and intrinsic characteristics (study design, sample size, etc.) of research studies in relation to their influence on practice patterns. A total of 353 surgeons completed the survey. Surgeons achieved consensus on the 'importance' of three key designs on their practices: randomised controlled trials (94%), meta-analyses (75%) and systematic reviews (66%). The vast majority of respondents support the use of current evidence over historical clinical training; however subjective factors such as journal reputation (72%) and investigator profile (68%) continue to influence clinical decision-making strongly. Although intrinsic factors such as study design and sample size have some influence on clinical decision-making, surgeon respondents are equally influenced by extrinsic factors such as investigator reputation and perceived journal quality.Cite this article: Dr M. Ghert. An international survey to identify the intrinsic and extrinsic factors of research studies most likely to change orthopaedic practice. Bone Joint Res 2016;5:130-136. DOI: 10.1302/2046-3758.54.2000578. © 2016 Ghert et al.

  11. Drug susceptibility testing in microaerophilic parasites: Cysteine strongly affects the effectivities of metronidazole and auranofin, a novel and promising antimicrobial

    Directory of Open Access Journals (Sweden)

    David Leitsch

    2017-12-01

    Full Text Available The microaerophilic parasites Entamoeba histolytica, Trichomonas vaginalis, and Giardia lamblia annually cause hundreds of millions of human infections which are treated with antiparasitic drugs. Metronidazole is the most often prescribed drug but also other drugs are in use, and novel drugs with improved characteristics are constantly being developed. One of these novel drugs is auranofin, originally an antirheumatic which has been relabelled for the treatment of parasitic infections. Drug effectivity is arguably the most important criterion for its applicability and is commonly assessed in susceptibility assays using in vitro cultures of a given pathogen. However, drug susceptibility assays can be strongly affected by certain compounds in the growth media. In the case of microaerophilic parasites, cysteine which is added in large amounts as an antioxidant is an obvious candidate because it is highly reactive and known to modulate the toxicity of metronidazole in several microaerophilic parasites.In this study, it was attempted to reduce cysteine concentrations as far as possible without affecting parasite viability by performing drug susceptibility assays under strictly anaerobic conditions in an anaerobic cabinet. Indeed, T. vaginalis and E. histolytica could be grown without any cysteine added and the cysteine concentration necessary to maintain G. lamblia could be reduced to 20%. Susceptibilities to metronidazole were found to be clearly reduced in the presence of cysteine. With auranofin the protective effect of cysteine was extreme, providing protection to concentrations up to 100-fold higher as observed in the absence of cysteine. With three other drugs tested, albendazole, furazolidone and nitazoxanide, all in use against G. lamblia, the effect of cysteine was less pronounced. Oxygen was found to have a less marked impact on metronidazole and auranofin than cysteine but bovine bile which is standardly used in growth media for G

  12. Strong Quantum Confinement Effects and Chiral Excitons in Bio-Inspired ZnO–Amino Acid Cocrystals

    KAUST Repository

    Muhammed, Madathumpady Abubaker Habeeb

    2018-02-20

    Elucidating the underlying principles behind band gap engineering is paramount for the successful implementation of semiconductors in photonic and optoelectronic devices. Recently it has been shown that the band gap of a wide and direct band gap semiconductor, such as ZnO, can be modified upon cocrystallization with amino acids, with the role of the biomolecules remaining unclear. Here, by probing and modeling the light-emitting properties of ZnO-amino acid cocrystals, we identify the amino acids\\' role on this band gap modulation and demonstrate their effective chirality transfer to the interband excitations in ZnO. Our 3D quantum model suggests that the strong band edge emission blue-shift in the cocrystals can be explained by a quasi-periodic distribution of amino acid potential barriers within the ZnO crystal lattice. Overall, our findings indicate that biomolecule cocrystallization can be used as a truly bio-inspired means to induce chiral quantum confinement effects in quasi-bulk semiconductors.

  13. Naegleria fowleri lysate induces strong cytopathic effects and pro-inflammatory cytokine release in rat microglial cells.

    Science.gov (United States)

    Lee, Yang-Jin; Park, Chang-Eun; Kim, Jong-Hyun; Sohn, Hae-Jin; Lee, Jinyoung; Jung, Suk-Yul; Shin, Ho-Joon

    2011-09-01

    Naegleria fowleri, a ubiquitous free-living ameba, causes fatal primary amebic meningoencephalitis in humans. N. fowleri trophozoites are known to induce cytopathic changes upon contact with microglial cells, including necrotic and apoptotic cell death and pro-inflammatory cytokine release. In this study, we treated rat microglial cells with amebic lysate to probe contact-independent mechanisms for cytotoxicity, determining through a combination of light microscopy and scanning and transmission electron microscopy whether N. fowleri lysate could effect on both necrosis and apoptosis on microglia in a time- as well as dose-dependent fashion. A (51)Cr release assay demonstrated pronounced lysate induction of cytotoxicity (71.5%) toward microglial cells by 24 hr after its addition to cultures. In an assay of pro-inflammatory cytokine release, microglial cells treated with N. fowleri lysate produced TNF-α, IL-6, and IL-1β, though generation of the former 2 cytokines was reduced with time, and that of the last increased throughout the experimental period. In summary, N. fowleri lysate exerted strong cytopathic effects on microglial cells, and elicited pro-inflammatory cytokine release as a primary immune response.

  14. Synergistic effect between strongly coupled CoAl layered double hydroxides and graphene for the electrocatalytic reduction of oxygen

    International Nuclear Information System (INIS)

    Wang, Yinling; Wang, Zhangcui; Wu, Xiaoqin; Liu, Xiaowang; Li, Maoguo

    2016-01-01

    Highlights: • CoAl-LDHs were synthesized on the surface of graphene oxide in situ. • The oxygen reduction reaction activity of the catalyst was investigated. • The synergistic effect between CoAl-LDHs and rGO is discussed in detail. • The roles of Co 2+ in the LDHs were clarified. - Abstract: Precious metal-free electrocatalysts with high efficiency and durability for the oxygen reduction reaction (ORR) are strongly desired in the field of energy technology. Herein, the CoAl layered double hydroxides (CoAl-LDHs)/reduced graphene oxide (rGO) composites were successfully prepared by growing CoAl-LDHs on the surface of GO in situ via coprecipitation and subsequently hydrothermal treatment. The structure, composition, morphology and ORR catalytic activity of the CoAl-LDHs/rGO composites were investigated as a function of mass ratios of CoAl-LDHs and GO. The results show that there is an optimum mass ratio of CoAl-LDHs and GO (w CoAl-LDHs :w GO = 1:5) for the ORR catalytic activity, where the electron transfer number for ORR at the CoAl-LDHs/rGO composites reaches to 3.5, closing to the full four-electron process. The synergistic effect between CoAl-LDHs and rGO is discussed in detail and the discussion is instructive for the construction of the better transition metal oxides/carbon composite-based ORR catalysts.

  15. Absence of cue-recruitment for extrinsic signals: sounds, spots, and swirling dots fail to influence perceived 3D rotation direction after training.

    Directory of Open Access Journals (Sweden)

    Anshul Jain

    2010-10-01

    Full Text Available The visual system can learn to use information in new ways to construct appearance. Thus, signals such as the location or translation direction of an ambiguously rotating wire frame cube, which are normally uninformative, can be learned as cues to determine the rotation direction. This perceptual learning occurs when the formerly uninformative signal is statistically associated with long-trusted visual cues (such as binocular disparity that disambiguate appearance during training. In previous demonstrations, the newly learned cue was intrinsic to the perceived object, in that the signal was conveyed by the same image elements as the object itself. Here we used extrinsic new signals and observed no learning. We correlated three new signals with long-trusted cues in the rotating cube paradigm: one crossmodal (an auditory signal and two within modality (visual. Cue recruitment did not occur in any of these conditions, either in single sessions or in ten sessions across as many days. These results suggest that the intrinsic/extrinsic distinction is important for the perceptual system in determining whether it can learn and use new information from the environment to construct appearance. Extrinsic cues do have perceptual effects (e.g. the "bounce-pass" illusion and McGurk effect, so we speculate that extrinsic signals must be recruited for perception, but only if certain conditions are met. These conditions might specify the age of the observer, the strength of the long-trusted cues, or the amount of exposure to the correlation.

  16. Accurate and automatic extrinsic calibration method for blade measurement system integrated by different optical sensors

    Science.gov (United States)

    He, Wantao; Li, Zhongwei; Zhong, Kai; Shi, Yusheng; Zhao, Can; Cheng, Xu

    2014-11-01

    Fast and precise 3D inspection system is in great demand in modern manufacturing processes. At present, the available sensors have their own pros and cons, and hardly exist an omnipotent sensor to handle the complex inspection task in an accurate and effective way. The prevailing solution is integrating multiple sensors and taking advantages of their strengths. For obtaining a holistic 3D profile, the data from different sensors should be registrated into a coherent coordinate system. However, some complex shape objects own thin wall feather such as blades, the ICP registration method would become unstable. Therefore, it is very important to calibrate the extrinsic parameters of each sensor in the integrated measurement system. This paper proposed an accurate and automatic extrinsic parameter calibration method for blade measurement system integrated by different optical sensors. In this system, fringe projection sensor (FPS) and conoscopic holography sensor (CHS) is integrated into a multi-axis motion platform, and the sensors can be optimally move to any desired position at the object's surface. In order to simple the calibration process, a special calibration artifact is designed according to the characteristics of the two sensors. An automatic registration procedure based on correlation and segmentation is used to realize the artifact datasets obtaining by FPS and CHS rough alignment without any manual operation and data pro-processing, and then the Generalized Gauss-Markoff model is used to estimate the optimization transformation parameters. The experiments show the measurement result of a blade, where several sampled patches are merged into one point cloud, and it verifies the performance of the proposed method.

  17. Simultaneous modulation of the intrinsic and extrinsic pathways by simvastatin in mediating prostate cancer cell apoptosis

    International Nuclear Information System (INIS)

    Goc, Anna; Kochuparambil, Samith T; Al-Husein, Belal; Al-Azayzih, Ahmad; Mohammad, Shuaib; Somanath, Payaningal R

    2012-01-01

    Recent studies suggest the potential benefits of statins as anti-cancer agents. Mechanisms by which statins induce apoptosis in cancer cells are not clear. We previously showed that simvastatin inhibit prostate cancer cell functions and tumor growth. Molecular mechanisms by which simvastatin induce apoptosis in prostate cancer cells is not completely understood. Effect of simvastatin on PC3 cell apoptosis was compared with docetaxel using apoptosis, TUNEL and trypan blue viability assays. Protein expression of major candidates of the intrinsic pathway downstream of simvastatin-mediated Akt inactivation was analyzed. Gene arrays and western analysis of PC3 cells and tumor lysates were performed to identify the candidate genes mediating extrinsic apoptosis pathway by simvastatin. Data indicated that simvastatin inhibited intrinsic cell survival pathway in PC3 cells by enhancing phosphorylation of Bad, reducing the protein expression of Bcl-2, Bcl-xL and cleaved caspases 9/3. Over-expression of PC3 cells with Bcl-2 or DN-caspase 9 did not rescue the simvastatin-induced apoptosis. Simvastatin treatment resulted in increased mRNA and protein expression of molecules such as TNF, Fas-L, Traf1 and cleaved caspase 8, major mediators of intrinsic apoptosis pathway and reduced protein levels of pro-survival genes Lhx4 and Nme5. Our study provides the first report that simvastatin simultaneously modulates intrinsic and extrinsic pathways in the regulation of prostate cancer cell apoptosis in vitro and in vivo, and render reasonable optimism that statins could become an attractive anti-cancer agent

  18. Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability.

    Science.gov (United States)

    Frielink, N; Schuengel, C; Embregts, P

    2017-07-01

    According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and integrated motivation. Although it has been argued theoretically that the different types of motivation are universally applicable, Reid et al. () proposed a dichotomy of broad subtypes of extrinsic motivation for people with intellectual disability (ID) due to their cognitive limitations. The current study challenges this proposal by testing whether the four subtypes of extrinsic motivation can be differentiated among people with ID as well. The subtypes of extrinsic motivation were measured using two adapted versions of the Self-Regulation Questionnaire, one regarding exercise and one regarding support. In total, 186 adults with mild to borderline ID participated in the study. Results supported the distinction between the four subtypes of extrinsic motivation regarding both exercise and support. In addition, the correlation coefficients supported a quasi-simplex pattern of correlations among the subtypes, indicating that adjacent subtypes were more closely related than non-adjacent subtypes. Moreover, the study showed sufficient Cronbach's alphas and test-retest reliabilities for early stage research. Overall, the results of the current study provide initial evidence for the universality of the four subtypes of extrinsic motivation across populations with and without ID. © 2017 The Authors. Journal of Intellectual Disability Research published by MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disibilities and John Wiley & Sons Ltd.

  19. Effects of strong interactions between Ti and ceria on the structures of Ti/CeO2.

    Science.gov (United States)

    Yao, Xiao-Dan; Zhu, Kong-Jie; Teng, Bo-Tao; Yu, Cao-Ming; Zhang, Yun-Lei; Liu, Ya; Fan, Maohong; Wen, Xiao-Dong

    2016-11-30

    The effects of strong interactions between Ti and ceria on the structures of Ti/CeO 2 (111) are systematically investigated by density functional theory calculation. To our best knowledge, the adsorption energy of a Ti atom at the hollow site of CeO 2 is the highest value (-7.99 eV) reported in the literature compared with those of Au (-0.88--1.26 eV), Ag (-1.42 eV), Cu (-2.69 eV), Pd (-1.75 eV), Pt (-2.62 eV) and Sn (-3.68 eV). It is very interesting to find that Ti adatoms disperse at the hollow site of CeO 2 (111) to form surface TiO x species, instead of aggregating to form Ti metal clusters for the Ti-CeO 2 interactions that are much stronger than those of Ti-Ti ones. Ti adatoms are completely oxidized to Ti 4+ ions if they are monatomically dispersed on the next near hollow sites of CeO 2 (111) (xTi-NN-hollow); while Ti 3+ ions are observed when they locate at the near hollow sites (xTi-N-hollow). Due to the electronic repulsive effects among Ti 3+ ions, the adsorption energies of xTi-N-hollow are slightly weaker than those of xTi-NN-hollow. Simultaneously, the existence of unstable Ti 3+ ions on xTi-N-hollow also leads to the restructuring of xTi-N-hollow by surface O atoms of ceria transferring to the top of Ti 3+ ions, or oxidation by O 2 adsorption and dissociation. Both processes improve the stability of the xTi/CeO 2 system by Ti 3+ oxidation. Correspondingly, surface TiO 2 -like species form. This work sheds light into the structures of metal/CeO 2 catalysts with strong interactions between the metal and the ceria support.

  20. Fitness Effects of Chlorpyrifos in the Damselfly Enallagma cyathigerum Strongly Depend upon Temperature and Food Level and Can Bridge Metamorphosis.

    Directory of Open Access Journals (Sweden)

    Lizanne Janssens

    Full Text Available Interactions between pollutants and suboptimal environmental conditions can have severe consequences for the toxicity of pollutants, yet are still poorly understood. To identify patterns across environmental conditions and across fitness-related variables we exposed Enallagma cyathigerum damselfly larvae to the pesticide chlorpyrifos at two food levels or at two temperatures and quantified four fitness-related variables (larval survival, development time, mass at emergence and adult cold resistance. Food level and temperature did not affect survival in the absence of the pesticide, yet the pesticide reduced survival only at the high temperature. Animals reacted to the pesticide by accelerating their development but only at the high food level and at the low temperature; at the low food level, however, pesticide exposure resulted in a slower development. Chlorpyrifos exposure resulted in smaller adults except in animals reared at the high food level. Animals reared at the low food level and at the low temperature had a higher cold resistance which was not affected by the pesticide. In summary our study highlight that combined effects of exposure to chlorpyrifos and the two environmental conditions (i were mostly interactive and sometimes even reversed in comparison with the effect of the environmental condition in isolation, (ii strongly differed depending on the fitness-related variable under study, (iii were not always predictable based on the effect of the environmental condition in isolation, and (iv bridged metamorphosis depending on which environmental condition was combined with the pesticide thereby potentially carrying over from aquatic to terrestrial ecosystems. These findings are relevant when extrapolating results of laboratory tests done under ideal environmental conditions to natural communities.

  1. Intrinsic and extrinsic rewards in a nonformal environmental education program.

    Science.gov (United States)

    Price, Emily A; Vining, Joanne; Saunders, Carol D

    2009-09-01

    Humans are surrounded by threats to the environment, many of their own making. The severity of environmental problems will not decrease unless action is taken to develop and encourage greater environmentally responsible behavior (ERB) in the general populace. Environmental education (EE) is one method for strengthening precursors to ERB such as knowledge and attitudes, but research on the connection is currently unclear. In this paper we present the results of a study investigating the role played by rewards in encouraging ERB precursors for adults and children involved in a zoo-based Nature Swap program. We used semistructured interviews to question 91 participants, including 38 children, 38 adult guardians, and 15 staff members regarding the importance of rewards in the program. We content analyzed the interviews to identify and describe major themes and then coded them. We found that adult guardians and Play Partners perceived intrinsic and extrinsic rewards as aiding in maintaining motivation and interest in the nonformal Nature Swap program. In addition, both children and adult companion participants in the program mentioned strengthened precursors to ERB. Overall we found that adult companions perceived that children who participated in the program spent more quality time outdoors and had a heightened awareness of their surroundings as a result of program-based rewards. Implications for other EE and conservation education programs are discussed.

  2. Rethinking the extrinsic incubation period of malaria parasites.

    Science.gov (United States)

    Ohm, Johanna R; Baldini, Francesco; Barreaux, Priscille; Lefevre, Thierry; Lynch, Penelope A; Suh, Eunho; Whitehead, Shelley A; Thomas, Matthew B

    2018-03-12

    The time it takes for malaria parasites to develop within a mosquito, and become transmissible, is known as the extrinsic incubation period, or EIP. EIP is a key parameter influencing transmission intensity as it combines with mosquito mortality rate and competence to determine the number of mosquitoes that ultimately become infectious. In spite of its epidemiological significance, data on EIP are scant. Current approaches to estimate EIP are largely based on temperature-dependent models developed from data collected on parasite development within a single mosquito species in the 1930s. These models assume that the only factor affecting EIP is mean environmental temperature. Here, we review evidence to suggest that in addition to mean temperature, EIP is likely influenced by genetic diversity of the vector, diversity of the parasite, and variation in a range of biotic and abiotic factors that affect mosquito condition. We further demonstrate that the classic approach of measuring EIP as the time at which mosquitoes first become infectious likely misrepresents EIP for a mosquito population. We argue for a better understanding of EIP to improve models of transmission, refine predictions of the possible impacts of climate change, and determine the potential evolutionary responses of malaria parasites to current and future mosquito control tools.

  3. Giant extrinsic negative thermal expansion in vanadium pentoxide nanocrystalline films

    Energy Technology Data Exchange (ETDEWEB)

    Bahgat, A.A. [Department of Physics, Faculty of Science, King Khaled University, P.O. Box 9004, Abha (Saudi Arabia); Department of Physics, Faculty of Science, Al-Azhar University, Nasr City 11884, Cairo (Egypt); Al-Hajry, A. [Department of Physics, Faculty of Science, King Khaled University, P.O. Box 9004, Abha (Saudi Arabia); El-Desoky, M.M. [Department of Physics, Faculty of Science, King Khaled University, P.O. Box 9004, Abha (Saudi Arabia); Department of Physics, Faculty of Education, Suez Canal University, Al-Arish (Egypt)

    2006-06-15

    Vanadium pentoxide gels, V{sub 2}O{sub 5}.1.6H{sub 2}O, give rise to xerogel layers that exhibit a preferred orientation. X-ray diffraction of this xerogel displays the 00l peaks typical of a turbostratic stacking of the V{sub 2}O{sub 5} ribbons along a direction parallel to the substrate. The distance along the c-axis is observed from the interlayer spacing to decrease continuously with increasing temperature up to 180 C, as observed by high-temperature X-ray diffraction. This contraction may be described by an extrinsic mechanism of negative thermal expansion (NTE). The coefficient of NTE as large as -1.5 x 10{sup -3} K{sup -1} was observed. Full recovery of the interlayer spacing is obtained after cooling the sample to room temperature in open air, where water molecules are reabsorbed, indicating that the process is reversible and the heating process can be repeated without losing NTE. The structure of the xerogel was explored further using differential scanning calorimetry as well as infrared spectroscopy. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Effects of Joint Interpretation of the Strong Interest Inventory and the Myers-Briggs Type Indicator in Career Choice.

    Science.gov (United States)

    Katz, Louise; Joyner, John W.; Seaman, Nancy

    1999-01-01

    Students completed either the Strong Interest Inventory (n=114) or Myers-Briggs Type Indicator (n=108), both (n=99), or none (n=106). Twelve weeks after interpretation, those who completed both showed more change, specificity, or certainty in their career goal. The Myers-Briggs proved as helpful as Strong in career decision making. (SK)

  5. A PHYSICAL MODEL OF THE EFFECT OF A SHALLOW WEAK LAYER ON STRONG GROUND MOTION FOR STRIKE-SLIP RUPTURES

    Energy Technology Data Exchange (ETDEWEB)

    JAMES N. BRUNE AND ABDOLRASOOL ANOOSHEHPOOR

    1998-02-23

    We report results of foam-rubber modeling of the effect of a shallow weak layer on ground motion from strike-slip ruptures. Computer modeling of strong ground motion from strike-slip earthquakes has involved somewhat arbitrary assumptions about the nature of slip along the shallow part of the fault (e.g., fixing the slip to be zero along the upper 2 kilometers of the fault plane) in order to match certain strong motion accelerograms. Most modeling studies of earthquake strong ground motion have used what is termed kinematic dislocation modeling. In kinematic modeling the time function for slip on the fault is prescribed, and the response of the layered medium is calculated. Unfortunately, there is no guarantee that the model and the prescribed slip are physically reasonable unless the true nature of the medium and its motions are known ahead of time. There is good reason to believe that in many cases faults are weak along the upper few kilometers of the fault zone and may not be able to maintain high levels of shear strain required for high dynamic energy release during earthquakes. Physical models of faulting, as distinct from numerical or mathematical models, are guaranteed to obey static and dynamic mechanical laws. Foam-rubber modeling studies have been reported in a number of publications. The object of this paper is to present results of physical modeling using a shallow weak layer, in order to verify the physical basis for assuming a long rise time and a reduced high frequency pulse for the slip on the shallow part of faults. It appears a 2-kilometer deep, weak zone along strike-slip faults could indeed reduce the high frequency energy radiated from shallow slip, and that this effect can best be represented by superimposing a small amplitude, short rise-time pulse at the onset of a much longer rise-time slip. A weak zone was modeled by inserting weak plastic layers of a few inches in thickness into the foam rubber model. For the 15 cm weak zone the average

  6. Intrinsic and extrinsic motivational orientations in the competitive context: an examination of person-situation interactions.

    Science.gov (United States)

    Abuhamdeh, Sami; Csikszentmihalyi, Mihaly

    2009-10-01

    The current study examined Intrinsic Motivation Orientation and Extrinsic Motivation Orientation (Work Preference Inventory; Amabile, Hill, Hennessey, & Tighe, 1994) as potential trait-level moderators of the way Internet chess players responded to the intrinsic and extrinsic rewards of the chess games they played. On the basis of the defining characteristics of these 2 types of motivational orientations, we predicted that (a) Intrinsic Motivation Orientation would be associated with a stronger curvilinear relationship between challenge and enjoyment and (b) Extrinsic Motivation Orientation would be associated with a heightened affective responsivity to competitive outcome (i.e., winning vs. losing). Results supported the predictions. Implications of the findings are discussed.

  7. Characterization of weak, fair and strong neutron absorbing materials by means of neutron transmission: Beam hardening effect

    International Nuclear Information System (INIS)

    Kharfi, F.; Bastuerk, M.; Boucenna, A.

    2006-01-01

    The characterization of neutron absorbing materials as well as quantification of neutron attenuation through matter is very essential in various fields, namely in shielding calculation. The objective of this work is to describe an experimental procedure to be used for the determination of neutron transmission through different materials. The proposed method is based on the relation between the gray value measured on neutron radiography image and the corresponding inducing neutron beam. For such a purpose, three kinds of materials (in shape of plate) were investigated using thermal neutrons: (1) boron-alloyed stainless steel as strong absorber; (2) copper and steel as fair absorbers and (3) aluminum as weak absorber. This work is not limited to the determination of neutron transmission through matters; it is also spread out to the measure of the surface density of the neutron absorbing elements (ρ s ) as a function of thickness of neutron absorbing material such as boron-alloyed stainless steel. The beam hardening effect depending on material thickness was also studied using the neutron transmission measurements. A theoretical approach was used to interpret the experimental results. The neutron transmission measurements were performed at the Neutron Radiography and Tomography facility of the Atomic Institute of the Austrian Universities in Vienna. Finally, a Maxwellian neutron distribution of incident neutron beam was used in the theoretical calculations of neutron energy shift in order to compare with experiments results. The obtained experimental results are in a good agreement with the developed theoretical approach

  8. Characterization of weak, fair and strong neutron absorbing materials by means of neutron transmission: Beam hardening effect

    Science.gov (United States)

    Kharfi, F.; Bastuerk, M.; Boucenna, A.

    2006-09-01

    The characterization of neutron absorbing materials as well as quantification of neutron attenuation through matter is very essential in various fields, namely in shielding calculation. The objective of this work is to describe an experimental procedure to be used for the determination of neutron transmission through different materials. The proposed method is based on the relation between the gray value measured on neutron radiography image and the corresponding inducing neutron beam. For such a purpose, three kinds of materials (in shape of plate) were investigated using thermal neutrons: (1) boron-alloyed stainless steel as strong absorber; (2) copper and steel as fair absorbers and (3) aluminum as weak absorber. This work is not limited to the determination of neutron transmission through matters; it is also spread out to the measure of the surface density of the neutron absorbing elements (ρs) as a function of thickness of neutron absorbing material such as boron-alloyed stainless steel. The beam hardening effect depending on material thickness was also studied using the neutron transmission measurements. A theoretical approach was used to interpret the experimental results. The neutron transmission measurements were performed at the Neutron Radiography and Tomography facility of the Atomic Institute of the Austrian Universities in Vienna. Finally, a Maxwellian neutron distribution of incident neutron beam was used in the theoretical calculations of neutron energy shift in order to compare with experiments results. The obtained experimental results are in a good agreement with the developed theoretical approach.

  9. Associations of Extrinsic and Intrinsic Components of Work Stress with Health: A Systematic Review of Evidence on the Effort-Reward Imbalance Model.

    Science.gov (United States)

    Siegrist, Johannes; Li, Jian

    2016-04-19

    Mainstream psychological stress theory claims that it is important to include information on people's ways of coping with work stress when assessing the impact of stressful psychosocial work environments on health. Yet, some widely used respective theoretical models focus exclusively on extrinsic factors. The model of effort-reward imbalance (ERI) differs from them as it explicitly combines information on extrinsic and intrinsic factors in studying workers' health. As a growing number of studies used the ERI model in recent past, we conducted a systematic review of available evidence, with a special focus on the distinct contribution of its intrinsic component, the coping pattern "over-commitment", towards explaining health. Moreover, we explore whether the interaction of intrinsic and extrinsic components exceeds the size of effects on health attributable to single components. Results based on 51 reports document an independent explanatory role of "over-commitment" in explaining workers' health in a majority of studies. However, support in favour of the interaction hypothesis is limited and requires further exploration. In conclusion, the findings of this review support the usefulness of a work stress model that combines extrinsic and intrinsic components in terms of scientific explanation and of designing more comprehensive worksite stress prevention programs.

  10. Integrating extrinsic and intrinsic cues into a minimal model of lineage commitment for hematopoietic progenitors.

    Directory of Open Access Journals (Sweden)

    Santhosh Palani

    2009-09-01

    Full Text Available Autoregulation of transcription factors and cross-antagonism between lineage-specific transcription factors are a recurrent theme in cell differentiation. An equally prevalent event that is frequently overlooked in lineage commitment models is the upregulation of lineage-specific receptors, often through lineage-specific transcription factors. Here, we use a minimal model that combines cell-extrinsic and cell-intrinsic elements of regulation in order to understand how both instructive and stochastic events can inform cell commitment decisions in hematopoiesis. Our results suggest that cytokine-mediated positive receptor feedback can induce a "switch-like" response to external stimuli during multilineage differentiation by providing robustness to both bipotent and committed states while protecting progenitors from noise-induced differentiation or decommitment. Our model provides support to both the instructive and stochastic theories of commitment: cell fates are ultimately driven by lineage-specific transcription factors, but cytokine signaling can strongly bias lineage commitment by regulating these inherently noisy cell-fate decisions with complex, pertinent behaviors such as ligand-mediated ultrasensitivity and robust multistability. The simulations further suggest that the kinetics of differentiation to a mature cell state can depend on the starting progenitor state as well as on the route of commitment that is chosen. Lastly, our model shows good agreement with lineage-specific receptor expression kinetics from microarray experiments and provides a computational framework that can integrate both classical and alternative commitment paths in hematopoiesis that have been observed experimentally.

  11. The Role of Extrinsic Rewards and Cue-Intention Association in Prospective Memory in Young Children.

    Directory of Open Access Journals (Sweden)

    Daniel Patrick Sheppard

    Full Text Available The current study examined, for the first time, the effect of cue-intention association, as well as the effects of promised extrinsic rewards, on prospective memory in young children, aged 5-years-old (n = 39 and 7-years-old (n = 40. Children were asked to name pictures for a toy mole, whilst also having to remember to respond differently to certain target pictures (prospective memory task. The level to which the target picture was associated with the intention was manipulated across two conditions (low- or high-association for all participants, whilst half of the participants were promised a reward for good prospective memory performance. Results showed a main effect of age, with the 7-year-olds outperforming the 5-year-olds. Furthermore, there was a main effect of reward, with those promised a reward performing better than those who were not. No effect was found for cue-association, with the participants of both age groups performing equally well in both association conditions. No significant interactions were found between any of the variables. The potentially important role of reward in young children's everyday prospective memory tasks, and possible reasons for the lack of a reflexive-associative effect, are discussed.

  12. The Role of Extrinsic Rewards and Cue-Intention Association in Prospective Memory in Young Children.

    Science.gov (United States)

    Sheppard, Daniel Patrick; Kretschmer, Anett; Knispel, Elisa; Vollert, Bianka; Altgassen, Mareike

    2015-01-01

    The current study examined, for the first time, the effect of cue-intention association, as well as the effects of promised extrinsic rewards, on prospective memory in young children, aged 5-years-old (n = 39) and 7-years-old (n = 40). Children were asked to name pictures for a toy mole, whilst also having to remember to respond differently to certain target pictures (prospective memory task). The level to which the target picture was associated with the intention was manipulated across two conditions (low- or high-association) for all participants, whilst half of the participants were promised a reward for good prospective memory performance. Results showed a main effect of age, with the 7-year-olds outperforming the 5-year-olds. Furthermore, there was a main effect of reward, with those promised a reward performing better than those who were not. No effect was found for cue-association, with the participants of both age groups performing equally well in both association conditions. No significant interactions were found between any of the variables. The potentially important role of reward in young children's everyday prospective memory tasks, and possible reasons for the lack of a reflexive-associative effect, are discussed.

  13. Extrinsic Calibration for Vehicle-based Mobile Mapping System

    Directory of Open Access Journals (Sweden)

    SHI Limei

    2015-01-01

    Full Text Available Having the advantage of 360° imaging and rotation invariance, panoramic camera has gradually been used in mobile mapping systems(MMS. Calibration is an essential requirement to make sure that MMS can get high quality geo-information. This paper presents a way to address the extrinsic calibration for vehicle-based MMS composed of panoramic camera and Position and Orientation System (POS. Firstly, control points in the natural scene are set up, whose spatial coordinates are measured with high precision. Secondly, a panoramic spherical model is constructed and panoramic image can be projected to this model by means of spherical reverse transformation projection. Then, localize and select the control points in 3D spherical panoramic view but not in panoramic distorted image directly, the spherical coordinates of control points in panoramic image are gotten. After points correspondence is established, make use of direct geo-reference positioning equation and coordinate transformation, the translation and rotation parameters of panoramic camera relative to POS are computed. Experiments are conducted separately in space city calibration site located in Beijing and the Binhai New Area in Tianjin using our approach. Test results are listed as follows. When the GPS signal are of good quality, absolute positioning mean square error of a point is 10.3 cm in two-dimension plane and 16.5 cm in height direction; Otherwise, it is 35.4 cm in two-dimension plane and 54.8 cm in height direction. The max relative error of distance measurement is about 5 cm over a short distance (distance<3 km, which is not obviously affected by the GPS signal quality.

  14. The dual effect of vegetation green-up date and strong wind on the return period of spring dust storms.

    Science.gov (United States)

    Feng, Jieling; Li, Ning; Zhang, Zhengtao; Chen, Xi

    2017-08-15

    Vegetation phenology changes have been widely applied in the disaster risk assessments of the spring dust storms, and vegetation green-up date shifts have a strong influence on dust storms. However, the effect of earlier vegetation green-up dates due to climate warming on the evaluation of dust storms return periods remains an important, but poorly understood issue. In this study, we evaluate the spring dust storm return period (February to June) in Inner Mongolia, Northern China, using 165 observations of severe spring dust storm events from 16 weather stations, and regional vegetation green-up dates as an integrated factor from NDVI (Normalized Difference Vegetation Index), covering a period from 1982 to 2007, by building the bivariate Copula model. We found that the joint return period showed better fitting results than without considering the integrated factor when the actual dust storm return period is longer than 2years. Also, for extremely severe dust storm events, the gap between simulation result and actual return period can be narrowed up to 0.4888years by using integrated factor. Furthermore, the risk map based on the return period results shows that the Mandula, Zhurihe, Sunitezuoqi, Narenbaolige stations are identified as high risk areas. In this study area, land surface is extensively covered by grasses and shrubs, vegetation green-up date can play a significant role in restraining spring dust storm outbreaks. Therefore, we suggest that Copula method can become a useful tool for joint return period evaluation and risk analysis of severe dust storms. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Strong enhancement of Penning ionization for asymmetric atom pairs in cold Rydberg gases: the Tom and Jerry effect

    KAUST Repository

    Efimov, D K

    2016-05-18

    We consider Penning ionization of Rydberg atom pairs as an Auger-type process induced by the dipole-dipole interaction and employ semiclassical formulae for dipole transitions to calculate the autoionization width as a function of the principal quantum numbers, n d, n i, of both atoms. While for symmetric atom pairs with the well-known increase of the autoionization width with increasing n 0 is obtained, the result for asymmetric pairs is counterintuitive - for a fixed n i of the ionizing atom of the pair, the autoionization width strongly increases with decreasing n d of the de-excited atom. For H Rydberg atoms this increase reaches two orders of magnitude at the maximum of the n d dependence, and the same type of counterintuitive behavior is exhibited also by Na, Rb and Cs atoms. This is a purely quantum-mechanical effect, which points towards existence of optimal (we call them \\'Tom\\' and \\'Jerry\\' for \\'big\\' and \\'small\\') pairs of Rydberg atoms with respect to autoionization efficiency. Building on the model of population redistribution in cold Rydberg gases proposed in [1], we demonstrate that population evolution following the initial laser excitation of Rydberg atoms in state n 0 would eventually lead to the formation of such Tom-Jerry pairs with which feature autoionization widths that are enhanced by several orders of magnitude compared to that of two atoms in the initial laser-excited state n 0. We also show that in the high-density regime of cold Rydberg gas experiments the ionization rate of Tom-Jerry pairs can be substantially larger than the blackbody radiation-induced photoionization rate. © 2016 IOP Publishing Ltd.

  16. Experimental investigation of effect of surface gravity waves and spray on heat and momentum flux at strong wind conditions

    Science.gov (United States)

    Troitskaya, Yuliya; Sergeev, Daniil; Vdovin, Maxim; Kandaurov, Alexander; Ermakova, Olga; Kazakov, Vassily

    2015-04-01

    The most important characteristics that determine the interaction between atmosphere and ocean are fluxes of momentum, heat and moisture. For their parameterization the dimensionless exchange coefficients (the surface drag coefficient CD and the heat transfer coefficient or the Stanton number CT) are used. Numerous field and laboratory experiments show that CD increases with increasing wind speed at moderate and strong wind, and as it was shows recently CD decreases at hurricane wind speed. Waves are known to increase the sea surface resistance due to enhanced form drag, the sea spray is considered as a possible mechanism of the 'drag reduction' at hurricane conditions. The dependence of heat transfer coefficient CD on the wind speed is not so certain and the role of the mechanism associated with the wave disturbances in the mass transfer is not completely understood. Observations and laboratory data show that this dependence is weaker than for the CD, and there are differences in the character of the dependence in different data sets. The purpose of this paper is investigation of the effect of surface waves on the turbulent exchange of momentum and heat within the laboratory experiment, when wind and wave parameters are maintained and controlled. The effect of spray on turbulent exchange at strong winds is also estimated. A series of experiments to study the processes of turbulent exchange of momentum and heat in a stably stratified temperature turbulent boundary layer air flow over waved water surface were carried out at the Wind - wave stratified flume of IAP RAS, the peculiarity of this experiment was the option to change the surface wave parameters regardless of the speed of the wind flow in the channel. For this purpose a polyethylene net with the variable depth (0.25 mm thick and a cell of 1.6 mm × 1.6mm) has been stretched along the channel. The waves were absent when the net was located at the level of the undisturbed water surface, and had maximum

  17. A validity generalization procedure to test relations between intrinsic and extrinsic motivation and influence tactics.

    Science.gov (United States)

    Barbuto, John E; Moss, Jennifer A

    2006-08-01

    The relations of intrinsic and extrinsic motivation with use of consultative, legitimating, and pressure influence tactics were examined using validity generalization procedures. 5 to 7 field studies with cumulative samples exceeding 800 were used to test each relationship. Significance was found for relation between agents' intrinsic motivation and their use of consultative influence tactics and agents' extrinsic motivation and their use of legitimating influence tactics.

  18. Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability

    OpenAIRE

    Frielink, N.; Schuengel, C.; Embregts, P.J.C.M.

    2017-01-01

    Background According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and integrated motivation. Although it has been argued theoretically that the different types of motivation are universally applicable, Reid et al. (2009) proposed a dichotomy of broad subtypes of extrins...

  19. A comparison of South African and German extrinsic and intrinsic motivation

    OpenAIRE

    Robin Snelgar; Stacy A. Shelton; Anne Giesser

    2017-01-01

    Background: Various researchers have identified a trend of individuals shifting their preference from extrinsic to intrinsic motivation. The authors aimed to research this phenomenon specifically within the context of two different cultures as to date, this had not been done. This research explored the differing levels of extrinsic and intrinsic motivation in Germans and South Africans. Aim: The main objective of this study was to investigate similarities and differences concerning extrins...

  20. The relationship between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation

    OpenAIRE

    Chengedzai Mafini; Nobukhosi Dlodlo

    2014-01-01

    Orientation: There is much research on extrinsic motivation, job satisfaction and life satisfaction in organisations. However, empirical evidence on how such factors affect employees in public organisations in developing countries is lacking. Research purpose: To examine the relationships between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation. Motivation for the study: Labour strife is an endemic phenomenon in South Africa’s publ...

  1. Extrinsic electromagnetic chirality in all-photodesigned one-dimensional THz metamaterials

    OpenAIRE

    Rizza, Carlo; Columbo, Lorenzo; Brambilla, Massimo; Prati, Franco; Ciattoni, Alessandro

    2016-01-01

    We suggest that all-photodesigned metamaterials, sub-wavelength custom patterns of photo-excited carriers on a semiconductor, can display an exotic extrinsic electromagnetic chirality in terahertz (THz) frequency range. We consider a photo-induced pattern exhibiting 1D geometrical chirality, i.e. its mirror image can not be superposed onto itself by translations without rotations and, in the long wavelength limit, we evaluate its bianisotropic response. The photo-induced extrinsic chirality t...

  2. The interplay of intrinsic and extrinsic bounded noises in biomolecular networks.

    Science.gov (United States)

    Caravagna, Giulio; Mauri, Giancarlo; d'Onofrio, Alberto

    2013-01-01

    After being considered as a nuisance to be filtered out, it became recently clear that biochemical noise plays a complex role, often fully functional, for a biomolecular network. The influence of intrinsic and extrinsic noises on biomolecular networks has intensively been investigated in last ten years, though contributions on the co-presence of both are sparse. Extrinsic noise is usually modeled as an unbounded white or colored gaussian stochastic process, even though realistic stochastic perturbations are clearly bounded. In this paper we consider Gillespie-like stochastic models of nonlinear networks, i.e. the intrinsic noise, where the model jump rates are affected by colored bounded extrinsic noises synthesized by a suitable biochemical state-dependent Langevin system. These systems are described by a master equation, and a simulation algorithm to analyze them is derived. This new modeling paradigm should enlarge the class of systems amenable at modeling. We investigated the influence of both amplitude and autocorrelation time of a extrinsic Sine-Wiener noise on: (i) the Michaelis-Menten approximation of noisy enzymatic reactions, which we show to be applicable also in co-presence of both intrinsic and extrinsic noise, (ii) a model of enzymatic futile cycle and (iii) a genetic toggle switch. In (ii) and (iii) we show that the presence of a bounded extrinsic noise induces qualitative modifications in the probability densities of the involved chemicals, where new modes emerge, thus suggesting the possible functional role of bounded noises.

  3. The interplay of intrinsic and extrinsic bounded noises in biomolecular networks.

    Directory of Open Access Journals (Sweden)

    Giulio Caravagna

    Full Text Available After being considered as a nuisance to be filtered out, it became recently clear that biochemical noise plays a complex role, often fully functional, for a biomolecular network. The influence of intrinsic and extrinsic noises on biomolecular networks has intensively been investigated in last ten years, though contributions on the co-presence of both are sparse. Extrinsic noise is usually modeled as an unbounded white or colored gaussian stochastic process, even though realistic stochastic perturbations are clearly bounded. In this paper we consider Gillespie-like stochastic models of nonlinear networks, i.e. the intrinsic noise, where the model jump rates are affected by colored bounded extrinsic noises synthesized by a suitable biochemical state-dependent Langevin system. These systems are described by a master equation, and a simulation algorithm to analyze them is derived. This new modeling paradigm should enlarge the class of systems amenable at modeling. We investigated the influence of both amplitude and autocorrelation time of a extrinsic Sine-Wiener noise on: (i the Michaelis-Menten approximation of noisy enzymatic reactions, which we show to be applicable also in co-presence of both intrinsic and extrinsic noise, (ii a model of enzymatic futile cycle and (iii a genetic toggle switch. In (ii and (iii we show that the presence of a bounded extrinsic noise induces qualitative modifications in the probability densities of the involved chemicals, where new modes emerge, thus suggesting the possible functional role of bounded noises.

  4. Fabrication of Ge Nanocrystals Doped Silica-on-Silicon Waveguides and Observation of Their Strong Quantum Confinement Effect

    DEFF Research Database (Denmark)

    Ou, Haiyan; Rottwitt, Karsten

    2008-01-01

    Standard silica-on-silicon waveguides with a core doped by Ge nanocrystals were fabricated using PECVD and RIE. Transmission of the waveguide was measured, and strong absorption peaks at 1056.8 nm, 1406 nm and 1263.2 nm were observed.......Standard silica-on-silicon waveguides with a core doped by Ge nanocrystals were fabricated using PECVD and RIE. Transmission of the waveguide was measured, and strong absorption peaks at 1056.8 nm, 1406 nm and 1263.2 nm were observed....

  5. Intrinsic or Extrinsic? Using Videogames to Motivate Stroke Survivors: A Systematic Review.

    Science.gov (United States)

    Swanson, LaTasha R; Whittinghill, David M

    2015-06-01

    The main objective of this study was to explore, via a systematic review of available literature, the effectiveness of videogame-based rehabilitation interventions on the motivation and health outcomes of stroke patients. Using a systematic literature review of 18 articles, we sought to address three key research questions: (1) Do videogames improve function or health outcomes among stroke survivors? (2) Do videogames increase stroke patients' motivation to engage in rehabilitation exercise and activities? (3) Which motivational techniques, principles, and theoretical frameworks have been applied in the reviewed studies? A key word search was conducted, and articles were coded for inclusion of motivational theories or principles, intervention effectiveness, and participants' motivation to perform tasks. Three motivational frameworks and principles were used (self-determination theory [SDT], flow theory, and operant conditioning) to investigate intrinsic and extrinsic approaches. Past research suggests videogame-based interventions are effective at improving and increasing a variety of health-related outcomes, including motor functioning, energy expenditure, muscle strength, and recovery times in stroke patients. Past evidence shows videogame-based interventions are a promising tool to motivate stroke patients' engagement in effective rehabilitation activities. This study also identifies an opportunity for future research to apply motivational theories from SDT to studies on stroke rehabilitation and videogames.

  6. Effects of obesity and body fat distribution on lipids and lipoproteins in nondiabetic American Indians: The Strong Heart Study.

    Science.gov (United States)

    Hu, D; Hannah, J; Gray, R S; Jablonski, K A; Henderson, J A; Robbins, D C; Lee, E T; Welty, T K; Howard, B V

    2000-09-01

    To examine the relationship between obesity and lipoprotein profiles and compare the effects of total obesity and central adiposity on lipids/lipoproteins in American Indians. Participants were 773 nondiabetic American Indian women and 739 men aged 45 to 74 years participating in the Strong Heart Study. Total obesity was estimated using body mass index (BMI). Central obesity was measured as waist circumference. Lipoprotein measures included triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, apolipoprotein AI (apoAI), and apolipoprotein B (apoB). Partial and canonical correlation analyses were used to examine the associations between obesity and lipids/ lipoproteins. Women were more obese than men in Arizona (median BMI 32.1 vs. 29.2 kg/m2) and South Dakota and North Dakota (28.3 vs. 28.0 kg/m2), but there was no sex difference in waist circumference. Men had higher apoB and lower apoAI levels than did women. In women, when adjusted for center, gender, and age, BMI was significantly related to HDL cholesterol (r = -0.24, p HDL cholesterol (r = -0.23, p correlated with triglycerides (r = 0.30, p correlated with HDL cholesterol (r = -0.35, p HDL cholesterol decreased with waist circumference (r = -0.36, p correlation analysis, waist circumference received a greater weight (0.86) than did BMI (0.17) in women. However, the canonical weights were similar for waist (0.46) and BMI (0.56) in men. Only HDL cholesterol (-1.02) carried greater weight in women, whereas in men, triglycerides (0.50), and HDL cholesterol (-0.64) carried a large amount of weight. All the correlation coefficients between BMI, waist circumference, and the first canonical variable of lipids/lipoproteins or between the individual lipid/lipoprotein variables and the first canonical variable of obesity were smaller in women than in men. Triglycerides and HDL cholesterol showed clinically meaningful changes with BMI and waist circumference in men. All

  7. SOLVENT EFFECTS IN THE LIQUID-PHASE HYDRATION OF CYCLOHEXENE CATALYZED BY A MACROPOROUS STRONG ACID ION-EXCHANGE RESIN

    NARCIS (Netherlands)

    PANNEMAN, HJ; BEENACKERS, AACM

    1992-01-01

    The liquid-phase hydration of cyclohexene, a pseudo first order reversible reaction catalyzed by a strong acid ion exchange resin, macroporous Amberlite XE 307, was investigated in solvent mixtures of water and sulfolane. A decrease by a factor of 3 and 6 is observed in the experimentally measured

  8. The Effects of Building Strong Families: A Healthy Marriage and Relationship Skills Education Program for Unmarried Parents

    Science.gov (United States)

    Wood, Robert G.; McConnell, Sheena; Moore, Quinn; Clarkwest, Andrew; Hsueh, JoAnn

    2012-01-01

    This article examines the impacts of Building Strong Families, a healthy marriage and relationship skills education program serving unmarried parents who were expecting or had recently had a baby. Based on a random assignment research design, the analysis uses survey data from more than 4,700 couples across eight research sites to estimate program…

  9. Photo-Acoustic Spectroscopy Reveals Extrinsic Optical Chirality in GaAs-Based Nanowires Partially Covered with Gold

    Science.gov (United States)

    Petronijevic, E.; Leahu, G.; Belardini, A.; Centini, M.; Li Voti, R.; Hakkarainen, T.; Koivusalo, E.; Rizzo Piton, M.; Suomalainen, S.; Guina, M.; Sibilia, C.

    2018-04-01

    We report on the extrinsic chirality behavior of GaAs-based NWs asymmetrically hybridized with Au. The samples are fabricated by a recently developed, lithography-free self-organized GaAs growth, with the addition of AlGaAs shell and GaAs supershell. The angled Au flux is then used to cover three-out-of-six sidewalls with a thin layer of Au. Oblique incidence and proper sample orientation can lead to circular dichroism. We characterize this chiral behavior at 532 {nm} and 980 {nm} by means of photo-acoustic spectroscopy, which directly measures the difference in absorption for the circularly polarized light of the opposite headedness. For the first time to our knowledge, circular dichroism is observed in both the amplitude and the phase of the photo-acoustic signal. We strongly believe that such samples can be used for chiral applications, spanning from circularly polarized light emission, to the enantioselectivity applications.

  10. Intrinsic and extrinsic factors affecting patient engagement in diabetes self-management: perspectives of a certified diabetes educator.

    Science.gov (United States)

    Rodriguez, Kellie M

    2013-02-01

    Patients with diabetes are responsible for the vast majority of management requirements of their condition. However, their ability and motivation to engage in required self-management behaviors may be mitigated by multiple intrinsic and extrinsic factors. Intrinsic barriers include attitudes and health beliefs, limited diabetes knowledge and technical skill, reduced functional health literacy, and inadequate self-efficacy to promote positive behavior change. Extrinsic barriers include financial considerations, inadequate family and community support systems, ineffective clinical relationships, and limited access to effective diabetes health care delivery. Diabetes providers have opportunities for enhancing patient engagement with clinical recommendations and diabetes self-management through effective communication, including efforts to contextually assess patients' perceptions of diabetes and how the condition fits within the context of their changing lives. This article provides a conceptual framework for establishing and building an effective clinical alliance with patients with the goal of empowering them to take more control of their diabetes and reduce their risks for poor diabetes outcomes. Copyright © 2013 Elsevier HS Journals, Inc. All rights reserved.

  11. Intrinsic and extrinsic motivations in primary care: an explanatory study among French general practitioners.

    Science.gov (United States)

    Sicsic, Jonathan; Le Vaillant, Marc; Franc, Carine

    2012-12-01

    Like many other OECD nations, France has implemented a pay-for-performance (P4P) model in primary care. However, the benefits have been debated, particularly regarding the possibly undesirable effects of extrinsic motivation (EM) on intrinsic motivation (IM). To examine the relationship between French GPs' IM and EM based on an intrinsic motivation composite score (IMCS) developed for this purpose. If a negative relationship is found, P4P schemes could have side effects on GPs' IM that is a key determinant of quality of care. From data on 423 GPs practicing in a region of France, IM indicators are selected using a multiple correspondence analysis and aggregated from a multilevel model. Several doctors' characteristics have significant impacts on IMCS variability, especially group practice and salaried practice. Qualitative EM variables are negatively correlated with the IMCS: GPs who report not being satisfied with their income or feeling "often" constrained by patients' requests in terms of consultations length and office appointments obtain a lower mean IMCS than other GPs. Our results provide a cautionary message to regulators who should take into account the potential side effects of increasing EM through policies such as P4P. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  12. Iron bioavailability studies as assessed by intrinsic and extrinsic labeling techniques

    International Nuclear Information System (INIS)

    Johnson, C.D.

    1985-01-01

    Although soybeans are a rich source of iron and incorporation of soy protein into diets is increasing, the presence of phytate or fiber endogenous to the seeds may inhibit total iron absorption from diets including soy protein. Four studies on iron bioavailability as assessed by intrinsic and extrinsic labeling techniques in rats were completed. The effect of previous dietary protein on the absorption of intrinsically 59 Fe labeled defatted soy flour was determined in rats. The results indicated that the type of dietary protein (animal vs. plant) in pre-test diets would have little influence on iron absorption from a single soy protein test meal. Therefore, adaptation of soy protein does not improve bioavailability of iron. Soybean hulls were investigated as a source of iron fortification in bread. The results indicated that retention of 59 Fe from white bread baked with soy hulls did not differ from white bread fortified with bakery grade ferrous sulfate. The effect of endogenous soybean phytate on iron absorption in rats was measured using seeds of varying phytate content and intrinsically labeled with 59 Fe. Increasing concentration of phytate in whole soybean flour had no significant effect on iron absorption

  13. Iron bioavailability studies as assessed by intrinsic and extrinsic labeling techniques

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, C.D.

    1985-01-01

    Although soybeans are a rich source of iron and incorporation of soy protein into diets is increasing, the presence of phytate or fiber endogenous to the seeds may inhibit total iron absorption from diets including soy protein. Four studies on iron bioavailability as assessed by intrinsic and extrinsic labeling techniques in rats were completed. The effect of previous dietary protein on the absorption of intrinsically /sup 59/Fe labeled defatted soy flour was determined in rats. The results indicated that the type of dietary protein (animal vs. plant) in pre-test diets would have little influence on iron absorption from a single soy protein test meal. Therefore, adaptation of soy protein does not improve bioavailability of iron. Soybean hulls were investigated as a source of iron fortification in bread. The results indicated that retention of /sup 59/Fe from white bread baked with soy hulls did not differ from white bread fortified with bakery grade ferrous sulfate. The effect of endogenous soybean phytate on iron absorption in rats was measured using seeds of varying phytate content and intrinsically labeled with /sup 59/Fe. Increasing concentration of phytate in whole soybean flour had no significant effect on iron absorption.

  14. Surfactant protein D delays Fas- and TRAIL-mediated extrinsic pathway of apoptosis in T cells.

    Science.gov (United States)

    Djiadeu, Pascal; Kotra, Lakshmi P; Sweezey, Neil; Palaniyar, Nades

    2017-05-01

    Only a few extracellular soluble proteins are known to modulate apoptosis. We considered that surfactant-associated protein D (SP-D), an innate immune collectin present on many mucosal surfaces, could regulate apoptosis. Although SP-D is known to be important for immune cell homeostasis, whether SP-D affects apoptosis is unknown. In this study we aimed to determine the effects of SP-D on Jurkat T cells and human T cells dying by apoptosis. Here we show that SP-D binds to Jurkat T cells and delays the progression of Fas (CD95)-Fas ligand and TRAIL-TRAIL receptor induced, but not TNF-TNF receptor-mediated apoptosis. SP-D exerts its effects by reducing the activation of initiator caspase-8 and executioner caspase-3. SP-D also delays the surface exposure of phosphatidylserine. The effect of SP-D was ablated by the presence of caspase-8 inhibitor, but not by intrinsic pathway inhibitors. The binding ability of SP-D to dying cells decreases during the early stages of apoptosis, suggesting the release of apoptotic cell surface targets during apoptosis. SP-D also delays FasL-induced death of primary human T cells. SP-D delaying the progression of the extrinsic pathway of apoptosis could have important implications in regulating immune cell homeostasis at mucosal surfaces.

  15. Strong coupling effects during X-pulse CPMG experiments recorded on heteronuclear ABX spin systems: artifacts and a simple solution

    International Nuclear Information System (INIS)

    Vallurupalli, Pramodh; Scott, Lincoln; Williamson, James R.; Kay, Lewis E.

    2007-01-01

    Simulation and experiment have been used to establish that significant artifacts can be generated in X-pulse CPMG relaxation dispersion experiments recorded on heteronuclear ABX spin-systems, such as 13 C i - 13 C j - 1 H, where 13 C i and 13 C j are strongly coupled. A qualitative explanation of the origin of these artifacts is presented along with a simple method to significantly reduce them. An application to the measurement of 1 H CPMG relaxation dispersion profiles in an HIV-2 TAR RNA molecule where all ribose sugars are protonated at the 2' position, deuterated at all other sugar positions and 13 C labeled at all sugar carbons is presented to illustrate the problems that strong 13 C- 13 C coupling introduces and a simple solution is proposed

  16. Calculations of the one-body electronic structure of the strongly correlated systems including self-energy effects

    Energy Technology Data Exchange (ETDEWEB)

    Costa-Quintana, J.; Sanchez-Lopez, M.M.; Lopez-Aguilar, F. [Grup d`Electromagnetisme, Edifici Cn, Universitat Autonoma de Barcelona 08193, Bellaterra, Barcelona (Spain)

    1996-10-01

    We give a method to obtain the quasiparticle band structure and renormalized density of states by diagonalizing the interacting system Green function. This method operates for any self-energy approximation appropriated to strongly correlated systems. Application to CeSi{sub 2} and YBa{sub 2}Cu{sub 3}O{sub 7} is analyzed as a probe for this band calculation method. {copyright} {ital 1996 The American Physical Society.}

  17. Effect of Strong Acid Functional Groups on Electrode Rise Potential in Capacitive Mixing by Double Layer Expansion

    KAUST Repository

    Hatzell, Marta C.

    2014-12-02

    © 2014 American Chemical Society. The amount of salinity-gradient energy that can be obtained through capacitive mixing based on double layer expansion depends on the extent the electric double layer (EDL) is altered in a low salt concentration (LC) electrolyte (e.g., river water). We show that the electrode-rise potential, which is a measure of the EDL perturbation process, was significantly (P = 10-5) correlated to the concentration of strong acid surface functional groups using five types of activated carbon. Electrodes with the lowest concentration of strong acids (0.05 mmol g-1) had a positive rise potential of 59 ± 4 mV in the LC solution, whereas the carbon with the highest concentration (0.36 mmol g-1) had a negative rise potential (-31 ± 5 mV). Chemical oxidation of a carbon (YP50) using nitric acid decreased the electrode rise potential from 46 ± 2 mV (unaltered) to -6 ± 0.5 mV (oxidized), producing a whole cell potential (53 ± 1.7 mV) that was 4.4 times larger than that obtained with identical electrode materials (from 12 ± 1 mV). Changes in the EDL were linked to the behavior of specific ions in a LC solution using molecular dynamics and metadynamics simulations. The EDL expanded in the LC solution when a carbon surface (pristine graphene) lacked strong acid functional groups, producing a positive-rise potential at the electrode. In contrast, the EDL was compressed for an oxidized surface (graphene oxide), producing a negative-rise electrode potential. These results established the linkage between rise potentials and specific surface functional groups (strong acids) and demonstrated on a molecular scale changes in the EDL using oxidized or pristine carbons.

  18. Strong anisotropic anomalous Hall effect and spin Hall effect in the chiral antiferromagnetic compounds Mn3X (X =Ge , Sn, Ga, Ir, Rh, and Pt)

    Science.gov (United States)

    Zhang, Yang; Sun, Yan; Yang, Hao; Železný, Jakub; Parkin, Stuart P. P.; Felser, Claudia; Yan, Binghai

    2017-02-01

    We have carried out a comprehensive study of the intrinsic anomalous Hall effect and spin Hall effect of several chiral antiferromagnetic compounds Mn3X (X = Ge, Sn, Ga, Ir, Rh and Pt) by ab initio band structure and Berry phase calculations. These studies reveal large and anisotropic values of both the intrinsic anomalous Hall effect and spin Hall effect. The Mn3X materials exhibit a noncollinear antiferromagnetic order which, to avoid geometrical frustration, forms planes of Mn moments that are arranged in a Kagome-type lattice. With respect to these Kagome planes, we find that both the anomalous Hall conductivity (AHC) and the spin Hall conductivity (SHC) are quite anisotropic for any of these materials. Based on our calculations, we propose how to maximize AHC and SHC for different materials. The band structures and corresponding electron filling, that we show are essential to determine the AHC and SHC, are compared for these different compounds. We point out that Mn3Ga shows a large SHC of about 600 (ℏ /e ) (Ωcm) -1 . Our work provides insights into the realization of strong anomalous Hall effects and spin Hall effects in chiral antiferromagnetic materials.

  19. Extrinsic innervation of ileum and pelvic flexure of foals with ileocolonic aganglionosis.

    Science.gov (United States)

    Giancola, F; Gentilini, F; Romagnoli, N; Spadari, A; Turba, M E; Giunta, M; Sadeghinezhad, J; Sorteni, C; Chiocchetti, R

    2016-10-01

    Equine ileocolonic aganglionosis, which is also called lethal white foal syndrome (LWFS), is a severe congenital condition characterized by the unsuccessful colonization of neural crest progenitors in the caudal part of the small intestine and the entire large intestine. LWFS, which is attributable to a mutation in the endothelin receptor B gene, is the horse equivalent of Hirschsprung's disease in humans. Affected foals suffer from aganglionosis or hypoganglionosis of the enteric ganglia resulting in intestinal akinesia and colic. In other species with aganglionosis, fibers of extrinsic origin show an abnormal distribution pattern within the gut wall, but we have no information to date regarding this occurrence in horses. Our present aim is to investigate the distribution of extrinsic sympathetic and sensory neural fibers in LWFS, focusing on ileum and the pelvic flexure of the colon of two LWFS foals compared with a control subject. The sympathetic fibers were immunohistochemically identified with the markers tyrosine hydroxylase and dopamine beta-hydroxylase. The extrinsic sensory fibers were identified with the markers Substance P (SP) and calcitonin gene-related peptide (CGRP). Since SP and CGRP are also synthesized by subclasses of horse intramural neurons, LWFS represents a good model for the selective study of extrinsic fiber distribution. Affected foals showed large bundles of extrinsic fibers, compared with the control, as observed in Hirschsprung's disease. Furthermore, altered adrenergic pathways were observed, prominently in the pelvic flexure. The numbers of SP- and CGRP-immunoreactive fibers in the muscle, a target of enteric neurons, were dramatically reduced, whereas fibers deduced to be extrinsic sensory axons persisted around submucosal blood vessels. Fiber numbers in the mucosa were reduced. Thus, extrinsic innervation, contributing to modulate enteric functions, might also be affected during LWFS.

  20. Intrinsic and Extrinsic Aspects on Campylobacter jejuni Biofilms

    Directory of Open Access Journals (Sweden)

    Roberta T. Melo

    2017-07-01

    Full Text Available Biofilm represents a way of life that allows greater survival of microorganisms in hostile habitats. Campylobacter jejuni is able to form biofilms in vitro and on surfaces at several points in the poultry production chain. Genetic determinants related to their formation are expressed differently between strains and external conditions are decisive in this respect. Our approach combines phylogenetic analysis and the presence of seven specific genes linked to biofilm formation in association with traditional microbiology techniques, using Mueller Hinton and chicken juice as substrates in order to quantify, classify, determine the composition and morphology of the biomass of simple and mixed biofilms of 30 C. jejuni strains. It also evaluates the inhibition of its formation by biocides commonly used in industry and also by zinc oxide nanoparticles. Genetic analysis showed high heterogeneity with the identification of 23 pulsotypes. Despite the diversity, the presence of flaA, cadF, luxS, dnaJ, htrA, cbrA, and sodB genes in all strains shows the high potential for biofilm formation. This ability was only expressed in chicken juice, where they presented phenotype of a strong biofilm producer, with a mean count of 7.37 log CFU/mL and an ultrastructure characteristic of mature biofilm. The composition of simple and mixed biofilms was predominantly composed by proteins. The exceptions were found in mixed biofilms with Pseudomonas aeruginosa, which includes a carbohydrate-rich matrix, lower ability to sessile form in chicken juice and compact architecture of the biofilm, this aspects are intrinsic to this species. Hypochlorite, chlorhexidine, and peracetic acid were more effective in controlling viable cells of C. jejuni in biofilm, but the existence of tolerant strains indicates exposure to sublethal concentrations and development of adaptation mechanisms. This study shows that in chicken juice C. jejuni presents greater potential in producing mature

  1. Energy Approach to Nuclei and Atoms in a Strong Laser Field: Stark Effect and Multi-photon Resonances

    International Nuclear Information System (INIS)

    Glushkov, A. V.; Khetselius, O. Yu.; Svinarenko, A. A.; Lovett, L.

    2010-01-01

    A consistent energy approach to nuclei and atoms in a strong electromagnetic (laser) field is presented. The photon emission and absorption lines are described by the moments of different orders, which are calculated with the use of the Gell-Mann and Low S-matrix adiabatic formalism. In relativistic version the Gell-Mann and Low formulae expresses an imaginary part of the energy shift ImE through the scattering matrix, including interaction of quantum system as with laser field as with a field of photon vacuum.

  2. Effect of Strongly Alkaline Electrolyzed Water on Silk Degumming and the Physical Properties of the Fibroin Fiber

    OpenAIRE

    Cao, Ting-Ting; Wang, Yuan-Jing; Zhang, Yu-Qing

    2013-01-01

    Strongly alkaline electrolyzed water (SAEW) was prepared by electrolysis of tap water in a laboratory-made water electrolyzer. The pH of stored SAEW was stable for more than one month. The hardness of the electrolyzed water was 30% lower and the Na(+) concentration was 18% higher than those of the tap water. Silkworm cocoon shells were boiled in pH 11.50 SAEW at a ratio of 1∶40∼80 (W/V) for 20 min and the sericin layers around the silk fibroin fibers were removed completely. The tensile prope...

  3. Vector chirality for effective total momentum Jeff in a nonfrustrated Mott insulator: Effects of strong spin-orbit coupling and broken inversion symmetry

    Science.gov (United States)

    Arakawa, Naoya

    2016-11-01

    I propose the emergence of the spin-orbital-coupled vector chirality in a nonfrustrated Mott insulator with the strong spin-orbit coupling due to a b -plane's inversion-symmetry (IS) breaking. I derive the superexchange interactions for a t2 g-orbital Hubbard model on a square lattice with the strong spin-orbit coupling and the IS-breaking-induced hopping integrals, and explain the microscopic origins of the Dzyaloshinsky-Moriya (DM) -type and the Kitaev-type interactions. Then, by adopting the mean-field approximation to a minimal model including only the Heisenberg-type and the DM-type nearest-neighbor interactions, I show that the IS breaking causes the spin-orbital-coupled chirality as a result of stabilizing the screw state. I also highlight the limit of the hard-pseudospin approximation in discussing the stability of the screw states in the presence of both the DM-type and the Kitaev-type interactions, and discuss its meaning. I finally discuss the effects of tetragonal crystal field and Jeff=3/2 states, and the application to the iridates near the [001 ] surface of Sr2IrO4 and the interface between Sr2IrO4 and Sr3Ir2O7 .

  4. Copper-65-absorption by men fed intrinsically and extrinsically labeled whole wheat bread

    International Nuclear Information System (INIS)

    Johnson, P.E.; Lykken, G.I.

    1988-01-01

    Six men were fed a diet composed of conventional foods with all bread as whole wheat bread. Intrinsically labeled 65 Cu bread (containing 6.5 ppm Cu and 48 atom % 65 Cu) was substituted for unlabeled bread for 3 days, and stools were collected for 24 days. Extrinsically labeled bread was then substituted for 3 days and another 24-day stool collection made. 65 Cu excretion was measured by mass spectrometry. Mean Cu intake was 1.10 mg of Cu/day. Average Cu balance was /minus/0.06 /+-/ 0.08 mg/day. Average absorption of the intrinsic copper was 72.2 /+-/ 9.3% and of extrinsic Cu 64.2 /+-/ 5.8%. The ratio of extrinsic to intrinsic absorption was 0.906 /+-/ 0.164. Absorption of intrinsic and extrinsic tracers did not differ significantly (p > 0.05) by a paired t-test, and the ratio (E/I) was not significantly different from 1. Use of extrinsic Cu tracers to assess Cu absorption is supported by these results

  5. The relationship between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation

    Directory of Open Access Journals (Sweden)

    Chengedzai Mafini

    2014-04-01

    Research purpose: To examine the relationships between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation. Motivation for the study: Labour strife is an endemic phenomenon in South Africa’s public sector as evidenced by the high incidences of industrial action and labour turnover. This study contributes to this subject by identifying the extrinsic factors that could be optimised with a view to enhancing job and life satisfaction amongst government employees. Research approach, design and method: The study used the quantitative research survey approach: a questionnaire was administered to 246 employees in a South African public organisation. Extrinsic motivation factors were identified using principal components analysis. Mean score ranking was used to compare the relative importance of all factors. The conceptual framework was tested using Spearman’s rank correlation analysis and linear regression analysis. Main findings: Statistically significant relationships were observed between job satisfaction and four extrinsic motivation factors: remuneration, quality of work life, supervision and teamwork. The relationship with promotion was insignificant, but a statistically significant relationship was established with life satisfaction. Practical/managerial implications: The findings may be used to implement strategies for enhancing employee performance and industrial relations within public organisations. Contribution/value-add: The study provides evidence of the interplay between extrinsic motivation, job satisfaction and life satisfaction for public servants in developing countries.

  6. Generic absence of strong singularities in loop quantum Bianchi-IX spacetimes

    Science.gov (United States)

    Saini, Sahil; Singh, Parampreet

    2018-03-01

    We study the generic resolution of strong singularities in loop quantized effective Bianchi-IX spacetime in two different quantizations—the connection operator based ‘A’ quantization and the extrinsic curvature based ‘K’ quantization. We show that in the effective spacetime description with arbitrary matter content, it is necessary to include inverse triad corrections to resolve all the strong singularities in the ‘A’ quantization. Whereas in the ‘K’ quantization these results can be obtained without including inverse triad corrections. Under these conditions, the energy density, expansion and shear scalars for both of the quantization prescriptions are bounded. Notably, both the quantizations can result in potentially curvature divergent events if matter content allows divergences in the partial derivatives of the energy density with respect to the triad variables at a finite energy density. Such events are found to be weak curvature singularities beyond which geodesics can be extended in the effective spacetime. Our results show that all potential strong curvature singularities of the classical theory are forbidden in Bianchi-IX spacetime in loop quantum cosmology and geodesic evolution never breaks down for such events.

  7. Seasonal climate manipulations have only minor effects on litter decomposition rates and N dynamics but strong effects on litter P dynamics of sub-arctic bog species.

    Science.gov (United States)

    Aerts, R; Callaghan, T V; Dorrepaal, E; van Logtestijn, R S P; Cornelissen, J H C

    2012-11-01

    Litter decomposition and nutrient mineralization in high-latitude peatlands are constrained by low temperatures. So far, little is known about the effects of seasonal components of climate change (higher spring and summer temperatures, more snow which leads to higher winter soil temperatures) on these processes. In a 4-year field experiment, we manipulated these seasonal components in a sub-arctic bog and studied the effects on the decomposition and N and P dynamics of leaf litter of Calamagrostis lapponica, Betula nana, and Rubus chamaemorus, incubated both in a common ambient environment and in the treatment plots. Mass loss in the controls increased in the order Calamagrostis Litter chemistry showed within each incubation environment only a few and species-specific responses. Compared to the interspecific differences, they resulted in only moderate climate treatment effects on mass loss and these differed among seasons and species. Neither N nor P mineralization in the litter were affected by the incubation environment. Remarkably, for all species, no net N mineralization had occurred in any of the treatments during 4 years. Species differed in P-release patterns, and summer warming strongly stimulated P release for all species. Thus, moderate changes in summer temperatures and/or winter snow addition have limited effects on litter decomposition rates and N dynamics, but summer warming does stimulate litter P release. As a result, N-limitation of plant growth in this sub-arctic bog may be sustained or even further promoted.

  8. Regorafenib induces extrinsic and intrinsic apoptosis through inhibition of ERK/NF-κB activation in hepatocellular carcinoma cells.

    Science.gov (United States)

    Tsai, Jai-Jen; Pan, Po-Jung; Hsu, Fei-Ting

    2017-02-01

    The aim of the present study was to investigate the role of NF-κB inactivation in regorafenib-induced apoptosis in human hepatocellular carcinoma SK-HEP-1 cells. SK-HEP-1 cells were treated with different concentrations of the NF-κB inhibitor 4-N-[2-(4-phenoxyphenyl)ethyl]quinazoline-4,6-diamine (QNZ) or regorafenib for different periods. The effects of QNZ and regorafenib on cell viability, expression of NF-κB-modulated anti-apoptotic proteins and apoptotic pathways were analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, western blotting, DNA gel electrophoresis, flow cytometry and NF-κB reporter gene assay. Inhibitors of various kinases including AKT, c-Jun N-terminal kinase (JNK), P38 and extracellular signal-regulated kinase (ERK) were used to evaluate the mechanism of regorafenib-induced NF-κB inactivation. The results demonstrated that both QNZ and regorafenib significantly inhibited the expression of anti-apoptotic proteins and triggered extrinsic and intrinsic apoptosis. We also demonstrated that regorafenib inhibited NF-κB activation through ERK dephosphorylation. Taken all together, our findings indicate that regorafenib triggers extrinsic and intrinsic apoptosis through suppression of ERK/NF-κB activation in SK-HEP-1 cells.

  9. Active hexose-correlated compound enhances extrinsic-pathway-mediated apoptosis of Acute Myeloid Leukemic cells.

    Directory of Open Access Journals (Sweden)

    Kavin Fatehchand

    Full Text Available Active Hexose Correlated Compound (AHCC has been shown to have many immunostimulatory and anti-cancer activities in mice and in humans. As a natural product, AHCC has potential to create safer adjuvant therapies in cancer patients. Acute Myeloid Leukemia (AML is the least curable and second-most common leukemia in adults. AML is especially terminal to those over 60 years old, where median survival is only 5 to 10 months, due to inability to receive intensive chemotherapy. Hence, the purpose of this study was to investigate the effects of AHCC on AML cells both in vitro and in vivo. Results showed that AHCC induced Caspase-3-dependent apoptosis in AML cell lines as well as in primary AML leukopheresis samples. Additionally, AHCC induced Caspase-8 cleavage as well as Fas and TRAIL upregulation, suggesting involvement of the extrinsic apoptotic pathway. In contrast, monocytes from healthy donors showed suppressed Caspase-3 cleavage and lower cell death. When tested in a murine engraftment model of AML, AHCC led to significantly increased survival time and decreased blast counts. These results uncover a mechanism by which AHCC leads to AML-cell specific death, and also lend support for the further investigation of AHCC as a potential adjuvant for the treatment of AML.

  10. The extrinsic cell death pathway and the élan mortel.

    Science.gov (United States)

    Wallach, D; Kang, T-B; Kovalenko, A

    2008-10-01

    Early in the exploration of the chemical nature of life, it was widely believed that the molecules of living organisms, by their very nature, differ from those of inorganic material molecules and possess a vital force ('élan vital'). Similarly, early scientific thinking on the subject of cell death and its induction by cytotoxic cells of the immune system was pervaded by a sense that the molecules mediating these functions possess intrinsic deadly activity and are dedicated exclusively to death-related tasks. This impression was also reflected in the initial notions of the mode of action of intracellular proteins that signal for death. It is now gradually becoming clear, however, that proteins participating in death induction also have functions unrelated to death. Nevertheless, as exemplified by studies of the function of caspase-8 (an enzyme that signals both for activation of the extrinsic cell-death pathway and for non-death-related effects), analysis of the mechanistic basis for such heterogeneity might allow identification of distinct structural determinants in the proteins participating in death induction that do bear death specificity.

  11. Strong Coupling Holography

    CERN Document Server

    Dvali, Gia

    2009-01-01

    We show that whenever a 4-dimensional theory with N particle species emerges as a consistent low energy description of a 3-brane embedded in an asymptotically-flat (4+d)-dimensional space, the holographic scale of high-dimensional gravity sets the strong coupling scale of the 4D theory. This connection persists in the limit in which gravity can be consistently decoupled. We demonstrate this effect for orbifold planes, as well as for the solitonic branes and string theoretic D-branes. In all cases the emergence of a 4D strong coupling scale from bulk holography is a persistent phenomenon. The effect turns out to be insensitive even to such extreme deformations of the brane action that seemingly shield 4D theory from the bulk gravity effects. A well understood example of such deformation is given by large 4D Einstein term in the 3-brane action, which is known to suppress the strength of 5D gravity at short distances and change the 5D Newton's law into the four-dimensional one. Nevertheless, we observe that the ...

  12. Strong-coupling approximations

    International Nuclear Information System (INIS)

    Abbott, R.B.

    1984-03-01

    Standard path-integral techniques such as instanton calculations give good answers for weak-coupling problems, but become unreliable for strong-coupling. Here we consider a method of replacing the original potential by a suitably chosen harmonic oscillator potential. Physically this is motivated by the fact that potential barriers below the level of the ground-state energy of a quantum-mechanical system have little effect. Numerically, results are good, both for quantum-mechanical problems and for massive phi 4 field theory in 1 + 1 dimensions. 9 references, 6 figures

  13. Strong interaction and QFD

    International Nuclear Information System (INIS)

    Ebata, T.

    1981-01-01

    With an assumed weak multiplet structure for bosonic hadrons, which is consistent with the ΔI = 1/2 rule, it is shown that the strong interaction effective hamiltonian is compatible with the weak SU(2) x U(1) gauge transformation. Especially the rho-meson transforms as a triplet under SU(2)sub(w), and this is the origin of the rho-photon analogy. It is also shown that the existence of the non-vanishing Cabibbo angle is a necessary condition for the absence of the exotic hadrons. (orig.)

  14. Multiorbital effects in strong-field ionization and dissociation of aligned polar molecules CH3I and CH3Br

    Science.gov (United States)

    Luo, Sizuo; Zhou, Shushan; Hu, Wenhui; Li, Xiaokai; Ma, Pan; Yu, Jiaqi; Zhu, Ruihan; Wang, Chuncheng; Liu, Fuchun; Yan, Bing; Liu, Aihua; Yang, Yujun; Guo, Fuming; Ding, Dajun

    2017-12-01

    Controlling the molecular axis offers additional ways to study molecular ionization and dissociation in strong laser fields. We measure the ionization and dissociation yields of aligned polar CH3X (X =I , Br) molecules in a linearly polarized femtosecond laser field. The current data show that maximum ionization occurs when the laser polarization is perpendicular to the molecular C -X axis, and dissociation prefers to occur at the laser polarization parallel to the C -X axis. The observed angular distributions suggest that the parent ions are generated by ionization from the HOMO. The angular distribution of fragment ions indicates that dissociation occurs mainly from an ionic excited state produced by ionization from the HOMO-1.

  15. Effect of the strong coupling on the exchange bias field in IrMn/Py/Ru/Co spin valves

    Science.gov (United States)

    Tarazona, H. S.; Alayo, W.; Landauro, C. V.; Quispe-Marcatoma, J.

    2018-01-01

    The IrMn/Py/Ru/Co (Py = Ni81Fe19) spin valves have been produced by sputtering deposition and analyzed by magnetization measurements and a theoretical modelling of their exchange interactions, based on the macro-spin model. The Ru thickness was grown between 6 and 22 Å, which is small enough to promote strong indirect coupling between Py and Co. Results of measurements showed a large and gradual change in the shape of hysteresis loops when the Ru thickness was varied. The theoretical analysis, using numerical calculations based on the gradient conjugate method, provides the exchange coupling constants (bilinear and biquadratic), the exchange anisotropy fields and the magnetic anisotropy fields (uniaxial and rotatable). The exchange bias fields of spin valves were compared to that of a IrMn/Py bilayer. We found that the difference between these fields oscillates with Ru thickness in the same manner as the bilinear coupling constants.

  16. Effects of a strong magnetic field on internal gravity waves: trapping, phase mixing, reflection and dynamical chaos

    Science.gov (United States)

    Loi, Shyeh Tjing; Papaloizou, John C. B.

    2018-04-01

    The spectrum of oscillation modes of a star provides information not only about its material properties (e.g. mean density), but also its symmetries. Spherical symmetry can be broken by rotation and/or magnetic fields. It has been postulated that strong magnetic fields in the cores of some red giants are responsible for their anomalously weak dipole mode amplitudes (the "dipole dichotomy" problem), but a detailed understanding of how gravity waves interact with strong fields is thus far lacking. In this work, we attack the problem through a variety of analytical and numerical techniques, applied to a localised region centred on a null line of a confined axisymmetric magnetic field which is approximated as being cylindrically symmetric. We uncover a rich variety of phenomena that manifest when the field strength exceeds a critical value, beyond which the symmetry is drastically broken by the Lorentz force. When this threshold is reached, the spatial structure of the g-modes becomes heavily altered. The dynamics of wave packet propagation transitions from regular to chaotic, which is expected to fundamentally change the organisation of the mode spectrum. In addition, depending on their frequency and the orientation of field lines with respect to the stratification, waves impinging on different parts of the magnetised region are found to undergo either reflection or trapping. Trapping regions provide an avenue for energy loss through Alfvén wave phase mixing. Our results may find application in various astrophysical contexts, including the dipole dichotomy problem, the solar interior, and compact star oscillations.

  17. Incorporating extrinsic noise into the stochastic simulation of biochemical reactions: A comparison of approaches

    Science.gov (United States)

    Thanh, Vo Hong; Marchetti, Luca; Reali, Federico; Priami, Corrado

    2018-02-01

    The stochastic simulation algorithm (SSA) has been widely used for simulating biochemical reaction networks. SSA is able to capture the inherently intrinsic noise of the biological system, which is due to the discreteness of species population and to the randomness of their reciprocal interactions. However, SSA does not consider other sources of heterogeneity in biochemical reaction systems, which are referred to as extrinsic noise. Here, we extend two simulation approaches, namely, the integration-based method and the rejection-based method, to take extrinsic noise into account by allowing the reaction propensities to vary in time and state dependent manner. For both methods, new efficient implementations are introduced and their efficiency and applicability to biological models are investigated. Our numerical results suggest that the rejection-based method performs better than the integration-based method when the extrinsic noise is considered.

  18. The relationship between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation

    Directory of Open Access Journals (Sweden)

    Chengedzai Mafini

    2014-02-01

    Full Text Available Orientation: There is much research on extrinsic motivation, job satisfaction and life satisfaction in organisations. However, empirical evidence on how such factors affect employees in public organisations in developing countries is lacking.Research purpose: To examine the relationships between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation.Motivation for the study: Labour strife is an endemic phenomenon in South Africa’s public sector as evidenced by the high incidences of industrial action and labour turnover. This study contributes to this subject by identifying the extrinsic factors that could be optimised with a view to enhancing job and life satisfaction amongst government employees.Research approach, design and method: The study used the quantitative research survey approach: a questionnaire was administered to 246 employees in a South African public organisation. Extrinsic motivation factors were identified using principal components analysis. Mean score ranking was used to compare the relative importance of all factors. The conceptual framework was tested using Spearman’s rank correlation analysis and linear regression analysis.Main findings: Statistically significant relationships were observed between job satisfaction and four extrinsic motivation factors: remuneration, quality of work life, supervision and teamwork. The relationship with promotion was insignificant, but a statistically significant relationship was established with life satisfaction.Practical/managerial implications: The findings may be used to implement strategies for enhancing employee performance and industrial relations within public organisations.Contribution/value-add: The study provides evidence of the interplay between extrinsic motivation, job satisfaction and life satisfaction for public servants in developing countries.

  19. Quantitative Trait Loci and Maternal Effects Affecting the Strong Grain Dormancy of Wild Barley (Hordeum vulgare ssp. spontaneum

    Directory of Open Access Journals (Sweden)

    Shingo Nakamura

    2017-10-01

    Full Text Available Wild barley (Hordeum vulgare ssp. spontaneum has strong grain dormancy, a trait that may enhance its survival in non-cultivated environments; by contrast, cultivated barley (Hordeum vulgare ssp. vulgare has weaker dormancy, allowing uniform germination in cultivation. Malting barley cultivars have been bred for especially weak dormancy to optimize their use in malt production. Here, we analyzed the genetic mechanism of this difference in seed dormancy, using recombinant inbred lines (RILs derived from a cross between the wild barley accession ‘H602’ and the malting barley cultivar ‘Kanto Nakate Gold (KNG’. Grains of H602 and KNG harvested at physiological maturity and dried at 30°C for 7 days had germination of approximately 0 and 100%, respectively. Analysis of quantitative trait loci (QTL affecting grain dormancy identified the well-known major dormancy QTL SD1 and SD2 (located near the centromeric region and at the distal end of the long arm of chromosome 5H, respectively, and QTL at the end of the long arm of chromosome 4H and in the middle of the long arm of chromosome 5H. We designated these four QTL Qsd1-OK, Qsd2-OK, Qsdw-4H, and Qsdw-5H, and they explained approximately 6, 38, 3, and 13% of the total phenotypic variation, respectively. RILs carrying H602 alleles showed increased dormancy levels for all QTL. The QTL acted additively and did not show epistasis or QTL–environment interactions. Comparison of QTL locations indicated that all QTL except Qsdw-5H are likely the same as the QTL previously detected in the doubled haploid population from a cross between the malting cultivar ‘Haruna Nijo’ and ‘H602.’ We further examined Qsd2-OK and Qsdw-5H by analyzing the segregation of phenotypes and genotypes of F2 progenies derived from crosses between RILs carrying specific segments of chromosome 5H from H602 in the KNG background. This analysis confirmed that the two genomic regions corresponding to these QTL are involved in

  20. Quantitative Trait Loci and Maternal Effects Affecting the Strong Grain Dormancy of Wild Barley (Hordeum vulgaressp.spontaneum).

    Science.gov (United States)

    Nakamura, Shingo; Pourkheirandish, Mohammad; Morishige, Hiromi; Sameri, Mohammad; Sato, Kazuhiro; Komatsuda, Takao

    2017-01-01

    Wild barley ( Hordeum vulgare ssp. spontaneum ) has strong grain dormancy, a trait that may enhance its survival in non-cultivated environments; by contrast, cultivated barley ( Hordeum vulgare ssp. vulgare ) has weaker dormancy, allowing uniform germination in cultivation. Malting barley cultivars have been bred for especially weak dormancy to optimize their use in malt production. Here, we analyzed the genetic mechanism of this difference in seed dormancy, using recombinant inbred lines (RILs) derived from a cross between the wild barley accession 'H602' and the malting barley cultivar 'Kanto Nakate Gold (KNG)'. Grains of H602 and KNG harvested at physiological maturity and dried at 30°C for 7 days had germination of approximately 0 and 100%, respectively. Analysis of quantitative trait loci (QTL) affecting grain dormancy identified the well-known major dormancy QTL SD1 and SD2 (located near the centromeric region and at the distal end of the long arm of chromosome 5H, respectively), and QTL at the end of the long arm of chromosome 4H and in the middle of the long arm of chromosome 5H. We designated these four QTL Qsd1-OK , Qsd2-OK , Qsdw-4H , and Qsdw-5H , and they explained approximately 6, 38, 3, and 13% of the total phenotypic variation, respectively. RILs carrying H602 alleles showed increased dormancy levels for all QTL. The QTL acted additively and did not show epistasis or QTL-environment interactions. Comparison of QTL locations indicated that all QTL except Qsdw-5H are likely the same as the QTL previously detected in the doubled haploid population from a cross between the malting cultivar 'Haruna Nijo' and 'H602.' We further examined Qsd2-OK and Qsdw-5H by analyzing the segregation of phenotypes and genotypes of F 2 progenies derived from crosses between RILs carrying specific segments of chromosome 5H from H602 in the KNG background. This analysis confirmed that the two genomic regions corresponding to these QTL are involved in the regulation of

  1. Computer tomographic patterns in extrinsic allergic alveolitis - a comparison with conventional radiological findings

    Energy Technology Data Exchange (ETDEWEB)

    Hieckel, H.G.; Mueller, S.; Luening, M.

    1986-10-01

    Seventeen patients with extrinsic allergic alveolitis or bird-fancier's lung were examined by standard radiological techniques and classified after Hapke's classification. In addition, the patients were examined by CT. The CT patterns have been analysed and compared with standard radiological findings. The methodological advantages of CT are discussed. Radiological investigation is of limited value in the diagnosis of extrinsic allergic alveolitis. Conventional radiography remains the standard of initial X-ray examination. In early cases, however, CT may be a valuable addition within the diagnostic strategy of a diagnostic imaging department.

  2. Substance use by college students: the role of intrinsic versus extrinsic motivation for athletic involvement.

    Science.gov (United States)

    Rockafellow, Bradley D; Saules, Karen K

    2006-09-01

    Certain types of athletic involvement may confer risk for substance use by college students. This study investigated whether motivational factors play a role in the relationship between athletic involvement and substance use. Intercollegiate athletes (n=98) and exercisers (n=120) were surveyed about substance use and motivation for athletic involvement. Athletes and exercisers who were extrinsically motivated had significantly higher rates of alcohol use than their intrinsically motivated counterparts. Results suggest that college students who are extrinsically motivated for involvement in physical activity/athletics--particularly those involved in team sports--may be in need of targeted prevention efforts. ((c) 2006 APA, all rights reserved).

  3. Ends, fundamental tones and capacity of minimal submanifolds via extrinsic comparison theory

    DEFF Research Database (Denmark)

    Gimeno, Vicent; Markvorsen, Steen

    2015-01-01

    We study the volume of extrinsic balls and the capacity of extrinsic annuli in minimal submanifolds which are properly immersed with controlled radial sectional curvatures into an ambient manifold with a pole. The key results are concerned with the comparison of those volumes and capacities with ...... with the corresponding entities in a rotationally symmetric model manifold. Using the asymptotic behavior of the volumes and capacities we then obtain upper bounds for the number of ends as well as estimates for the fundamental tone of the submanifolds in question....

  4. On the possible effect of round-the-world surface seismic waves in the dynamics of repeated shocks after strong earthquakes

    Science.gov (United States)

    Zotov, O. D.; Zavyalov, A. D.; Guglielmi, A. V.; Lavrov, I. P.

    2018-01-01

    Based on the observation data for hundreds of the main shocks and thousands of aftershocks, the existence of effect of round-the-world surface seismic waves is demonstrated (let us conditionally refer to them as a round-the-world seismic echo) and the manifestations of this effect in the dynamics of the repeated shocks of strong earthquakes are analyzed. At the same time, we by no means believe this effect has been fully proven. We only present a version of our own understanding of the physical causes of the observed phenomenon and analyze the regularities in its manifestation. The effect is that the surface waves excited in the Earth by the main shock make a full revolution around the Earth and excite a strong aftershock in the epicentral zone of the main shock. In our opinion, the physical nature of this phenomenon consists in the fact that the superposition leads to a concentration of wave energy when the convergent surface waves reach the epicentral zone (cumulative effect). The effect of the first seismic echo is most manifest. Thus, the present work supports our hypothesis of the activation of rock failure under the cumulative impact of an round-the-world seismic echo on the source area which is releasing ("cooling") after the main shock. The spatial regularities in the manifestations of this effect are established, and the independence of the probability of its occurrence on the main shock magnitude is revealed. The effect of a round-the-world seismic echo can be used to improve the reliability of the forecasts of strong aftershocks in determining the scenario for the seismic process developing in the epicentral zone of a strong earthquake that has taken place.

  5. Development of a Newtron-Krylov Iterative Method to Address Strong Non-Linear Feedback Effect in BWR Core Simulators

    International Nuclear Information System (INIS)

    Doddy Kastanya; Paul Turinsky

    2002-01-01

    A Newton-BICGSTAB solver has been developed to reduce the CPU execution time of BWR core simulators. The new solver treats the strong non-linearities in the problem explicitly using the Newton's method, replacing the traditionally used nested iterative approach. The Newton's method provides the solver with a higher-than-linear convergence rate, assuming that a good initial estimate of the unknowns is provided. Within each Newton iteration, an appropriately preconditioned BICGSTAB method is utilized for solving the linearized system of equations. Taking advantage of the higher convergence rate provided by the Newton's method and utilizing an efficient preconditioned BICGSTAB solver, we have developed a computationally efficient Newton-BICGSTAB solver to evaluate the three-dimensional, two-group neutron diffusion equations coupled with a two-phase flow model within a BWR core simulator. The robustness of the solver has been tested against numerous BWR core configurations and consistent results have been observed each time. The Newton-BICGSTAB solver provides an overall speedup of around 1.7 to the core simulator, with reference to the traditional approach. Isolating the solver portion of the core simulator, one can see that the new algorithm actually provides a speedup of around 1.9, of which 48% can be attributed to the BICGSTAB solver and the remaining 52% to Newton's method

  6. Comparing the epidermal growth factor interaction with four different cell lines: intriguing effects imply strong dependency of cellular context.

    Directory of Open Access Journals (Sweden)

    Hanna Björkelund

    Full Text Available The interaction of the epidermal growth factor (EGF with its receptor (EGFR is known to be complex, and the common over-expression of EGF receptor family members in a multitude of tumors makes it important to decipher this interaction and the following signaling pathways. We have investigated the affinity and kinetics of (125I-EGF binding to EGFR in four human tumor cell lines, each using four culturing conditions, in real time by use of LigandTracer®.Highly repeatable and precise measurements show that the overall apparent affinity of the (125I-EGF - EGFR interaction is greatly dependent on cell line at normal culturing conditions, ranging from K(D ≈ 200 pM on SKBR3 cells to K(D≈8 nM on A431 cells. The (125I-EGF - EGFR binding curves (irrespective of cell line have strong signs of multiple simultaneous interactions. Furthermore, for the cell lines A431 and SKOV3, gefitinib treatment increases the (125I-EGF - EGFR affinity, in particular when the cells are starved. The (125I-EGF - EGFR interaction on cell line U343 is sensitive to starvation while as on SKBR3 it is insensitive to gefitinib and starvation.The intriguing pattern of the binding characteristics proves that the cellular context is important when deciphering how EGF interacts with EGFR. From a general perspective, care is advisable when generalizing ligand-receptor interaction results across multiple cell-lines.

  7. Effects of strong earthquakes in variations of electrical and meteorological parameters of the near-surface atmosphere in Kamchatka region

    Science.gov (United States)

    Smirnov, S. E.; Mikhailova, G. A.; Mikhailov, Yu. M.; Kapustina, O. V.

    2017-09-01

    The diurnal variations in electrical (quasistatic electric field and electrical conductivity) and meteorological (temperature, pressure, relative humidity of the atmosphere, and wind speed) parameters, measured simultaneously before strong earthquakes in Kamchatka region (November 15, 2006, M = 8.3; January 13, 2007, M = 8.1; January 30, 2016, M = 7.2), are studied for the first time in detail. It is found that a successively anomalous increase in temperature, despite the negative regular trend in these winter months, was observed in the period of six-seven days before the occurrences of earthquakes. An anomalous temperature increase led to the formation of "winter thunderstorm" conditions in the near-surface atmosphere of Kamchatka region, which was manifested in the appearance of an anomalous, type 2 electrical signal, the amplification of and intensive variations in electrical conductivity, heavy precipitation (snow showers), high relative humidity of air, storm winds, and pressure changes. With the weak flow of natural heat radiation in this season, the observed dynamics of electric and meteorological processes can likely be explained by the appearance of an additional heat source of seismic nature.

  8. Effect of Strongly Alkaline Electrolyzed Water on Silk Degumming and the Physical Properties of the Fibroin Fiber.

    Directory of Open Access Journals (Sweden)

    Ting-Ting Cao

    Full Text Available Strongly alkaline electrolyzed water (SAEW was prepared by electrolysis of tap water in a laboratory-made water electrolyzer. The pH of stored SAEW was stable for more than one month. The hardness of the electrolyzed water was 30% lower and the Na(+ concentration was 18% higher than those of the tap water. Silkworm cocoon shells were boiled in pH 11.50 SAEW at a ratio of 1∶40∼80 (W/V for 20 min and the sericin layers around the silk fibroin fibers were removed completely. The tensile properties and thermal decomposition temperature of a single filament of silk fibroin obtained by the SAEW method were almost the same as those for the fiber obtained by the neutral soap, and much higher than those for the fiber obtained by Na2CO3 degumming. The results demonstrate that SAEW is an environmentally friendly and pollution-free silk degumming agent that allows highly efficient, low cost recovery of sericin.

  9. Effect of Strongly Alkaline Electrolyzed Water on Silk Degumming and the Physical Properties of the Fibroin Fiber.

    Science.gov (United States)

    Cao, Ting-Ting; Wang, Yuan-Jing; Zhang, Yu-Qing

    2013-01-01

    Strongly alkaline electrolyzed water (SAEW) was prepared by electrolysis of tap water in a laboratory-made water electrolyzer. The pH of stored SAEW was stable for more than one month. The hardness of the electrolyzed water was 30% lower and the Na(+) concentration was 18% higher than those of the tap water. Silkworm cocoon shells were boiled in pH 11.50 SAEW at a ratio of 1∶40∼80 (W/V) for 20 min and the sericin layers around the silk fibroin fibers were removed completely. The tensile properties and thermal decomposition temperature of a single filament of silk fibroin obtained by the SAEW method were almost the same as those for the fiber obtained by the neutral soap, and much higher than those for the fiber obtained by Na2CO3 degumming. The results demonstrate that SAEW is an environmentally friendly and pollution-free silk degumming agent that allows highly efficient, low cost recovery of sericin.

  10. Cost-effectiveness of the strong African American families-teen program: 1-year follow-up.

    Science.gov (United States)

    Ingels, Justin B; Corso, Phaedra S; Kogan, Steve M; Brody, Gene H

    2013-12-01

    Alcohol use poses a major threat to the health and well being of rural African American adolescents by negatively impacting academic performance, health, and safety. However, rigorous economic evaluations of prevention programs targeting this population are scarce. Cost-effectiveness analyses were conducted of SAAF-T relative to an attention-control intervention (ACI), as part of a randomized prevention trial. Outcomes of interest were the number of alcohol use and binge drinking episodes prevented, one year following the intervention. Incremental cost-effectiveness ratios (ICERs) and cost-effectiveness acceptability curves (CEACs) were used to determine the cost-effectiveness of SAAF-T compared to the ACI intervention. For the 473 participating youth completing baseline and follow-up assessments, the incremental per participant costs were $168, while the incremental per participant effects were 3.39 episodes of alcohol use prevented and 1.36 episodes of binge drinking prevented. Compared to the ACI intervention, the SAAF-T program cost $50 per reduction in an alcohol use episode and $123 per reduced episode of binge drinking. For the CEACs, at thresholds of $100 and $440, SAAF-T has at least a 90% probability of being cost-effective, relative to the ACI, for reductions in alcohol use and binge drinking episodes, respectively. The SAAF-T intervention provides a potentially cost-effective means for reducing the African American youths' alcohol use and binge drinking episodes. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  11. EXAMINING THE EFFECTS OF ORGANIZATIONAL COMMITMENT ON MOTIVATION VIA STRUCTURAL EQUATION MODELLING: TURKISH ACADEMICIANS CASE

    OpenAIRE

    Saraçlı, Sinan; KESKINTURK, Timur; CİCEK, Mukades; GAZELOGLU, Cengiz

    2014-01-01

    Earlier studies on motivation have all showed that there is a strong correlation between the organizational commitments and motivations of the workers. The purpose of this study is to investigate the effects of organizational commitment on individual’s extrinsic and intrinsic motivation which are effective factors of job motivation. With this purpose Explanatory Factor Analysis and Structural Equation Modelling (SEM) used to determine the effects of three sub factors of organizational commitm...

  12. The Effects of Chronic Nitrate Supplementation and the Use of Strong and Weak Antibacterial Agents on Plasma Nitrite Concentration and Exercise Blood Pressure.

    Science.gov (United States)

    McDonagh, S T J; Wylie, L J; Winyard, P G; Vanhatalo, A; Jones, A M

    2015-12-01

    Chlorhexidine-containing mouthwash (STRONG), which disturbs oral microflora, has been shown to diminish the rise in plasma nitrite concentration ([NO2-]) and attenuate the reduction in resting blood pressure (BP) typically seen after acute nitrate (NO3-) ingestion. We aimed to determine whether STRONG and weaker antiseptic agents attenuate the physiological effects of chronic NO3- supplementation using beetroot juice (BR). 12 healthy volunteers mouth-rinsed with STRONG, non-chlorhexidine mouthwash (WEAK) and deionised water (CON) 3 times a day, and ingested 70 mL BR (6.2 mmol NO3-), twice a day, for 6 days. BP (at rest and during 10 min of treadmill walking) and plasma and salivary [NO3-] and [NO2-] were measured prior to and on day 6 of supplementation. The change in salivary [NO3-] 4 h post final ingestion was higher (P0.05). However, during treadmill walking, the increase in systolic and mean arterial BP was higher 4 h after the final nitrate bolus in STRONG compared with CON (P<0.05) but not WEAK. The results indicate that both strong and weak antibacterial agents suppress the rise in plasma [NO2-] observed following the consumption of a high NO3- diet and the former can influence the BP response during low-intensity exercise. © Georg Thieme Verlag KG Stuttgart · New York.

  13. A model for the training effects in swimming demonstrates a strong relationship between parasympathetic activity, performance and index of fatigue.

    Directory of Open Access Journals (Sweden)

    Sébastien Chalencon

    Full Text Available Competitive swimming as a physical activity results in changes to the activity level of the autonomic nervous system (ANS. However, the precise relationship between ANS activity, fatigue and sports performance remains contentious. To address this problem and build a model to support a consistent relationship, data were gathered from national and regional swimmers during two 30 consecutive-week training periods. Nocturnal ANS activity was measured weekly and quantified through wavelet transform analysis of the recorded heart rate variability. Performance was then measured through a subsequent morning 400 meters freestyle time-trial. A model was proposed where indices of fatigue were computed using Banister's two antagonistic component model of fatigue and adaptation applied to both the ANS activity and the performance. This demonstrated that a logarithmic relationship existed between performance and ANS activity for each subject. There was a high degree of model fit between the measured and calculated performance (R(2=0.84±0.14,p<0.01 and the measured and calculated High Frequency (HF power of the ANS activity (R(2=0.79±0.07, p<0.01. During the taper periods, improvements in measured performance and measured HF were strongly related. In the model, variations in performance were related to significant reductions in the level of 'Negative Influences' rather than increases in 'Positive Influences'. Furthermore, the delay needed to return to the initial performance level was highly correlated to the delay required to return to the initial HF power level (p<0.01. The delay required to reach peak performance was highly correlated to the delay required to reach the maximal level of HF power (p=0.02. Building the ANS/performance identity of a subject, including the time to peak HF, may help predict the maximal performance that could be obtained at a given time.

  14. Strong Erosion-Driven Nongravitational Effects in Orbital Motions of the Kreutz Sungrazing System’s Dwarf Comets

    Science.gov (United States)

    Sekanina, Zdenek; Kracht, Rainer

    2015-03-01

    We investigate the relationships among the angular orbital elements—the longitude of the ascending node Ω, the inclination i, and the argument of perihelion ω—of the Kreutz system’s faint, dwarf sungrazers observed only with the Solar and Heliospheric Observatory/STEREO coronagraphs; their published orbits were derived using a parabolic, purely gravitational approximation. In a plot of i against Ω the bright Kreutz sungrazers (such as C/1843 D1, C/1882 R1, C/1963 R1, etc.) fit a curve of fixed apsidal orientation, whereas the dwarf members are distributed along a curve that makes with the apsidal curve an angle of 15°. The dwarf sungrazers’ perihelion longitude is statistically invariable, but their perihelion latitude increases systematically with Ω. We find that this trend can be explained by a strong erosion-driven nongravitational acceleration normal to the orbit plane, confirmed for several test dwarf Kreutz sungrazers by orbital solutions with nongravitational terms incorporated directly in the equations of motion on a condition of fixed apsidal orientation. Proceeding in three steps, we first apply Marsden et al.'s standard formalism, solving for the normal acceleration only, and eventually relax additional constraints on the nongravitational law and the acceleration’s radial and transverse components. The resulting nongravitational accelerations on the dwarf sungrazers exceed the maximum for cataloged comets in nearly parabolic orbits by up to three orders of magnitude, topping in exceptional cases the Sun’s gravitational acceleration! A mass-loss model suggests that the dwarf sungrazers’ nuclei fragment copiously and their dimensions diminish rapidly near the Sun, implying the objects’ imminent demise shortly before they reach perihelion.

  15. Strong WW Interaction at LHC

    Energy Technology Data Exchange (ETDEWEB)

    Pelaez, Jose R

    1998-12-14

    We present a brief pedagogical introduction to the Effective Electroweak Chiral Lagrangians, which provide a model independent description of the WW interactions in the strong regime. When it is complemented with some unitarization or a dispersive approach, this formalism allows the study of the general strong scenario expected at the LHC, including resonances.

  16. Effects of strong inter-hydrogen bond dynamical couplings in the polarized IR spectra of adipic acid crystals

    Energy Technology Data Exchange (ETDEWEB)

    Flakus, Henryk T., E-mail: flakus@ich.us.edu.pl [Institute of Chemistry, University of Silesia, 9 Szkolna Street, Pl-40-006 Katowice (Poland); Tyl, Aleksandra; Jablonska, Magdalena [Institute of Chemistry, University of Silesia, 9 Szkolna Street, Pl-40-006 Katowice (Poland)

    2009-10-16

    This paper presents the results of the re-investigation of polarized IR spectra of adipic acid and of its d{sub 2}, d{sub 8} and d{sub 10} deuterium derivative crystals. The spectra were measured at 77 K by a transmission method using polarized light for two different crystalline faces. Theoretical analysis concerned linear dichroic effects and H/D isotopic effects observed in the spectra of the hydrogen and deuterium bonds in adipic acid crystals at the frequency ranges of the {nu}{sub O-H} and the {nu}{sub O-D} bands. The two-branch fine structure pattern of the {nu}{sub O-H} and {nu}{sub O-D} bands and the basic linear dichroic effects characterizing them were ascribed to the vibronic mechanism of vibrational dipole selection rule breaking for IR transitions in centrosymmetric hydrogen bond dimers. It was proved that for isotopically diluted crystalline samples of adipic acid, a non-random distribution of protons and deuterons occurs in the dimers (H/D isotopic 'self-organization' effect). This effect results from the dynamical co-operative interactions involving the dimeric hydrogen bonds.

  17. Effects of strong inter-hydrogen bond dynamical couplings in the polarized IR spectra of adipic acid crystals

    Science.gov (United States)

    Flakus, Henryk T.; Tyl, Aleksandra; Jablońska, Magdalena

    2009-10-01

    This paper presents the results of the re-investigation of polarized IR spectra of adipic acid and of its d2, d8 and d10 deuterium derivative crystals. The spectra were measured at 77 K by a transmission method using polarized light for two different crystalline faces. Theoretical analysis concerned linear dichroic effects and H/D isotopic effects observed in the spectra of the hydrogen and deuterium bonds in adipic acid crystals at the frequency ranges of the νO-H and the νO-D bands. The two-branch fine structure pattern of the νO-H and νO-D bands and the basic linear dichroic effects characterizing them were ascribed to the vibronic mechanism of vibrational dipole selection rule breaking for IR transitions in centrosymmetric hydrogen bond dimers. It was proved that for isotopically diluted crystalline samples of adipic acid, a non-random distribution of protons and deuterons occurs in the dimers (H/D isotopic " self-organization" effect). This effect results from the dynamical co-operative interactions involving the dimeric hydrogen bonds.

  18. Complex interplay between intrinsic and extrinsic drivers of long-term survival trends in southern elephant seals

    Directory of Open Access Journals (Sweden)

    McMahon Clive R

    2007-03-01

    Full Text Available Abstract Background Determining the relative contribution of intrinsic and extrinsic factors to fluctuations in population size, trends and demographic composition is analytically complex. It is often only possible to examine the combined effects of these factors through measurements made over long periods, spanning an array of population densities or levels of food availability. Using age-structured mark-recapture models and datasets spanning five decades (1950–1999, and two periods of differing relative population density, we estimated age-specific probabilities of survival and examined the combined effects of population density and environmental conditions on juvenile survival of southern elephant seals at Macquarie Island. Results First-year survival decreased with density during the period of highest population size, and survival increased during years when the Southern Oscillation Index (SOI anomaly (deviation from a 50-year mean during the mother's previous foraging trip to sea was positive (i.e., El Niño. However, when environmental stochasticity and density were considered together, the effect of density on first-year survival effectively disappeared. Ignoring density effects also leads to models placing too much emphasis on the environmental conditions prevailing during the naïve pup's first year at sea. Conclusion Our analyses revealed that both the state of the environment and population density combine to modify juvenile survival, but that the degree to which these processes contributed to the variation observed was interactive and complex. This underlines the importance of evaluating the relative contribution of both the intrinsic and extrinsic factors that regulate animal populations because false conclusions regarding the importance of population regulation may be reached if they are examined in isolation.

  19. Downstream modulation of extrinsic apoptotic pathway in streptozotocin-induced Alzheimer's dementia in rats: Erythropoietin versus curcumin.

    Science.gov (United States)

    Samy, Doaa M; Ismail, Cherine A; Nassra, Rasha A; Zeitoun, Teshreen M; Nomair, Azhar M

    2016-01-05

    Erythropoietin and curcumin showed promising neuroprotective effects in various models of Alzheimer's dementia. This study was designed to compare the beneficial effects of erythropoietin and/or curcumin in intracerebro-ventricular (ICV) streptozotocin-induced Alzheimer's like disease in rats. Rats received ICV injection of either saline (control, n=8 rats), or streptozotocin. Three weeks following surgery, streptozotocin-injected rats were assigned into 4 groups (8 rats each); vehicle, curcumin (80mg/kg/day, orally), erythropoietin (500 IU/kg every other day, intraperitoneally) and combined (curcumin and erythropoietin)-treated groups. After 3 months of treatment, rats were subjected to neurobehavioral testing, and then killed for biochemical and histological assessment of hippocampus. Fas ligand protein and caspase-8 activity as mediators of extrinsic apoptotic pathway, oxidative stress markers (malondialdehyde and reduced glutathione) and β-amyloid (1-40 and 1-42) peptides were measured. The results showed that administration of erythropoietin suppressed extrinsic apoptosis better than curcumin, while curcumin was more effective in combating oxidative stress in ICV-streptozotocin injected rats. Both erythropoietin and curcumin treatments (individually or combined) equally reduced the hippocampal β-amyloid accumulation and improved cognitive impairment in Morris water maze and passive avoidance tasks. The combined treatment was the most effective in ameliorating apoptosis and oxidative stress rather than behavioral responses or β-amyloid burden. In conclusion, ICV-streptozotocin-induced Alzheimer's dementia activates hippocampal Fas ligand-mediated apoptosis, which could be reduced by erythropoietin and/or curcumin treatment. Curcumin supplementation alone could ameliorate cognitive deficits and reverse biochemical alterations in ICV-streptozotocin Alzheimer's rat model without the hazardous polycythemic effect of long-term erythropoietin injection. Copyright

  20. The SNARC effect in the processing of second-language number words: further evidence for strong lexico-semantic connections.

    Science.gov (United States)

    De Brauwer, Jolien; Duyck, Wouter; Brysbaert, Marc

    2008-03-01

    We present new evidence that word translation involves semantic mediation. It has been shown that participants react faster to small numbers with their left hand and to large numbers with their right hand. This SNARC (spatial-numerical association of response codes) effect is due to the fact that in Western cultures the semantic number line is oriented from left (small) to right (large). We obtained a SNARC effect when participants had to indicate the parity of second-language (L2) number words, but not when they had to indicate whether L2 number words contained a particular sound. Crucially, the SNARC effect was also obtained in a translation verification task, indicating that this task involved the activation of number magnitude.

  1. Concentration and timing of application reveal strong fungistatic effect of tebuconazole in a Daphnia-microparasitic yeast model.

    Science.gov (United States)

    Cuco, Ana P; Santos, Joana I; Abrantes, Nelson; Gonçalves, Fernando; Wolinska, Justyna; Castro, Bruno B

    2017-12-01

    Given the importance of pollutant effects on host-parasite relationships and disease spread, the main goal of this study was to assess the influence of different exposure scenarios for the fungicide tebuconazole (concentration×timing of application) on a Daphnia-microparasitic yeast experimental system. Previous results had demonstrated that tebuconazole is able to suppress Metschnikowia bicuspidata infection at ecologically-relevant concentrations; here, we aimed to obtain an understanding of the mechanism underlying the anti-parasitic (fungicidal or fungistatic) action of tebuconazole. We exposed the Daphnia-yeast system to four nominal tebuconazole concentrations at four timings of application (according to the predicted stage of parasite development), replicated on two Daphnia genotypes, in a fully crossed experiment. An "all-or-nothing" effect was observed, with tebuconazole completely suppressing infection from 13.5μgl -1 upwards, independent of the timing of tebuconazole application. A follow-up experiment confirmed that the suppression of infection occurred within a narrow range of tebuconazole concentrations (3.65-13.5μgl -1 ), although a later application of the fungicide had to be compensated for by a slight increase in concentration to elicit the same anti-parasitic effect. The mechanism behind this anti-parasitic effect seems to be the inhibition of M. bicuspidata sporulation, since tebuconazole was effective in preventing ascospore production even when applied at a later time. However, this fungicide also seemed to affect the vegetative growth of the yeast, as demonstrated by the enhanced negative effect of the parasite (increasing mortality in one of the host genotypes) at a later time of application of tebuconazole, when no signs of infection were observed. Fungicide contamination can thus affect the severity and spread of disease in natural populations, as well as the inherent co-evolutionary dynamics in host-parasite systems. Copyright © 2017

  2. Aharonov-Casher and spin Hall effects in mesoscopic ring structures with strong spin-orbit interaction

    Czech Academy of Sciences Publication Activity Database

    Borunda, M.F.; Liu, X.; Kovalev, A.A.; Liu, X.-J.; Jungwirth, Tomáš; Sinova, J.

    2008-01-01

    Roč. 78, č. 24 (2008), 245315/1-245315/9 ISSN 1098-0121 R&D Projects: GA MŠk LC510; GA AV ČR KAN400100652; GA ČR GEFON/06/E002 EU Projects: European Commission(XE) 015728 - NANOSPIN Institutional research plan: CEZ:AV0Z10100521 Keywords : Aharonov-Casher effect * spin Hall effect * spin-orbit interaction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.322, year: 2008

  3. Distinctive activation patterns under intrinsically versus extrinsically driven cognitive loads in prefrontal cortex: a near-infrared spectroscopy study using a driving video game.

    Science.gov (United States)

    Liu, Tao; Saito, Hirofumi; Oi, Misato

    2012-01-11

    To investigate the neural bases of intrinsically and extrinsically driven cognitive loads in daily life, we measured repetitively prefrontal activation in three (one control and two experimental) groups during a driving video game using near-infrared spectroscopy. The control group drove to goal four times with distinct route-maps illustrating default turning points. In contrast, the memory group drove the memorized default route without a route-map, and the emergency group drove with a route-map, but was instructed to change the default route by an extrinsically given verbal command (turn left or right) as an envisioned emergency. The predictability of a turning point in the route in each group was relatively different: due to extrinsic dictate of others in the emergency group, intrinsic memory in the memory group, and route-map aid in the control group. We analyzed concentration changes of oxygenated hemoglobin (CoxyHb) in the three critical periods (pre-turning, actual-turning, and post-turning). The emergency group showed a significantly increasing pattern of CoxyHb throughout the three periods, and a significant reduction in CoxyHb throughout the repetitive trials, but the memory group did not, even though both experimental groups showed higher activation than the control group in the pre-turning period. These results suggest that the prefrontal cortex differentiates the intrinsically (memory) and the extrinsically (dictate of others) driven cognitive loads according to the predictability of turning behavior, although the two types of cognitive loads commonly show increasing activation in the pre-turning period as the preparation effect. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  4. Selective accumulation and strong photodynamic effects of a new photosensitizer, ATX-S10.Na (II), in experimental malignant glioma.

    Science.gov (United States)

    Yamamoto, Junkoh; Hirano, Toru; Li, Shaoyi; Koide, Masayo; Kohno, Eiji; Inenaga, Chikanori; Tokuyama, Tsutomu; Yokota, Naoki; Yamamoto, Seiji; Terakawa, Susumu; Namba, Hiroki

    2005-11-01

    We investigated the feasibility of a novel photosensitizer, ATX-S10.Na (II), in photodynamic therapy (PDT) for glioma. First, PDT was performed in various brain tumor cell lines in vitro. Cytotoxicity depended upon both drug concentration and laser energy and the 50% inhibitory concentration ranged from 3.5 to 20 microg/ml. Next, PDT was performed in the subcutaneous and intracranial 9L tumor models in Fischer rats using ATX-S10.Na (II) and light from a 670-nm diode laser delivered by intratumoral insertion of an optical fiber. The effect of PDT on brain tumors was evaluated using magnetic resonance imaging. Sequential changes of the ATX-S10.Na (II) concentrations were also measured quantitatively by fluorospectrometry up to 12 h after intravenous administration in rats with intracranial and subcutaneous tumors. The concentration of ATX-S10.Na (II) in the brain tumor reached a maximum at 2 h after administration and the tumor/normal brain concentration ratio was as high as 131 at 8 h. Intratumoral PDT for intracranial tumors irradiated at this timing showed an obvious anti-tumor effect without severe side effects. The present study demonstrated the highly selective accumulation of ATX-S10.Na (II) in tumor tissue and its potent photodynamic effect in an experimental malignant glioma model.

  5. Strong Geometrical Effects in Submillimeter Selective Area Growth and Light Extraction of GaN Light Emitting Diodes on Sapphire

    Science.gov (United States)

    Tanaka, Atsunori; Chen, Renjie; Jungjohann, Katherine L.; Dayeh, Shadi A.

    2015-11-01

    Advanced semiconductor devices often utilize structural and geometrical effects to tailor their characteristics and improve their performance. We report here detailed understanding of such geometrical effects in the epitaxial selective area growth of GaN on sapphire substrates and utilize them to enhance light extraction from GaN light emitting diodes. Systematic size and spacing effects were performed side-by-side on a single 2” sapphire substrate to minimize experimental sampling errors for a set of 144 pattern arrays with circular mask opening windows in SiO2. We show that the mask opening diameter leads to as much as 4 times increase in the thickness of the grown layers for 20 μm spacings and that spacing effects can lead to as much as 3 times increase in thickness for a 350 μm dot diameter. We observed that the facet evolution in comparison with extracted Ga adatom diffusion lengths directly influences the vertical and lateral overgrowth rates and can be controlled with pattern geometry. Such control over the facet development led to 2.5 times stronger electroluminescence characteristics from well-faceted GaN/InGaN multiple quantum well LEDs compared to non-faceted structures.

  6. The ecological effects of water level fluctuation and phosphate enrichment in mesotrophic peatlands are strongly mediated by soil chemistry

    NARCIS (Netherlands)

    Mettrop, I.S.; Rutte, M.D.; Kooijman, A.M.; Lamers, L.P.M.

    2015-01-01

    Since the re-establishment of a more natural water regime is considered by water management in wetlands with artificially stable water levels, the biogeochemical and ecological effects of water level fluctuation with different nutrient loads should be investigated. This is particularly important for

  7. What makes coaches tick? The impact of coaches' intrinsic and extrinsic motives on their own satisfaction and that of their athletes.

    Science.gov (United States)

    Jowett, S

    2008-10-01

    This study aims to investigate the influence of two types of motivational forces on coach and athlete satisfaction. The focus is on intrinsic and extrinsic motives that initiate coach-related behavior. A questionnaire that measures both types of motivation and three facets of satisfaction (i.e., satisfaction with performance, with instruction, and with the coach-athlete relationship) was completed by 138 coaches. One athlete from each of the coaches who participated in the study was also asked to complete a questionnaire that measures their satisfaction with performance, instruction, and the coach-athlete relationship. Results from a series of regression analyses indicated that while intrinsic motivation was moderately and positively related to all facets of coach satisfaction, extrinsic motivation was only related to coach satisfaction with the coach-athlete relationship. Athletes' satisfaction with the coach-athlete relationship was only associated with the coach's intrinsic motivation. Interaction effects among the two types of motivation were significant suggesting that extrinsic motivation can potentially undermine intrinsic motivation when intrinsic motivation is low. The findings are discussed based on assumptions put forward by self-determination theory.

  8. <strong>Relative Biological Effect of Antiprotonsstrong>> strong>

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael

    purpose/objective The AD-4/ACE collaboration has recently performed experiments to directly measure the RBE of antiprotons. Antiprotons have very similar stopping power compared to protons, but when they come to rest, antiprotons will annihilate on a target nucleus and thereby release almost 2 Ge......V of energy. About 30 MeV of this energy is deposited in the vicinity of the Bragg-peak, thereby significantly enhancing it. It is furthermore expected that this additional energy is deposited by radiation which carries a high-LET component. This will have a significant influence on the radiobiological...... nuclear research facility CERN. A beam of 126 MeV antiprotons, corresponding to about 12 cm range in water, was spread out to a SOBP with a width of 1 cm. Dosimetry experiments were carried out with ionization chambers, alanine pellets and radiochromic film, and the results were used for benchmarking...

  9. Pesticide interactions with soil affected by olive mill wastewater (OMW): how strong and long-lasting is the OMW effect?

    Science.gov (United States)

    Keren, Yonatan; Borisover, Mikhail; Schaumann, Gabriele E.; Diehl, Dörte; Tamimi, Nisreen; Bukhanovsky, Nadezhda

    2017-04-01

    Sorption interactions with soils are well known to control the environmental fate of multiple organic compounds including pesticides. Pesticide-soil interactions may be affected by organic amendments or organic matter (OM)-containing wastewater brought to the field. Specifically, land spreading of olive mill wastewater (OMW), occurring intentionally or not, may also influence pesticide-soil interactions. The effects of the OMW disposed in the field on soil properties, including their ability to interact with pesticides, become of great interest due to the increasing demand for olive oil and a constant growth of world oil production. This paper summarizes some recent findings related to the effect of prior OMW land application on the ability of soils to interact with the organic compounds including pesticides, diuron and simazine. The major findings are as following: (1) bringing OMW to the field increases the potential of soils to sorb non-ionized pesticides; (2) this sorption increase may not be related solely to the increase in soil organic carbon content but it can reflect also the changes in the soil sorption mechanisms; (3) increased pesticide interactions with OMW-affected soils may become irreversible, due, assumedly, to the swelling of some components of the OMW-treated soil; (4) enhanced pesticide-soil interactions mitigate with the time passed after the OMW application, however, in the case of diuron, the remaining effect could be envisioned at least 600 days after the normal OMW application; (5) the enhancement effect of OMW application on soil sorption may increase with soil depth, in the 0-10 cm interval; (6) at higher pesticide (diuron) concentrations, larger extents of sorption enhancement, following the prior OMW-soil interactions, may be expected; (7) disposal of OMW in the field may be seasonal-dependent, and, in the case studied, it led to more distinct impacts on sorption when carried out in spring and winter, as compared with summer. It appears

  10. Testing strong interaction theories

    International Nuclear Information System (INIS)

    Ellis, J.

    1979-01-01

    The author discusses possible tests of the current theories of the strong interaction, in particular, quantum chromodynamics. High energy e + e - interactions should provide an excellent means of studying the strong force. (W.D.L.)

  11. Strong influence of long-distance edge effect on herb-layer vegetation in forest fragments in an agricultural landscape

    Czech Academy of Sciences Publication Activity Database

    Hofmeister, J.; Hošek, J.; Brabec, Marek; Hédl, Radim; Modrý, M.

    2013-01-01

    Roč. 15, č. 6 (2013), s. 293-303 ISSN 1433-8319 Grant - others:GA MŽP(CZ) SM/6/69/05; GA MŽP(CZ) SP/2D3/139/07 Institutional support: RVO:67985807 ; RVO:67985939 Keywords : ancient forest * edge effect * habitat fragmentation * light condition * soil nutrients * species richness Subject RIV: BB - Applied Statistics, Operational Research; EH - Ecology, Behaviour (BU-J) Impact factor: 3.324, year: 2013

  12. Concentration and timing of application reveal strong fungistatic effect of tebuconazole in a Daphnia-microparasitic yeast model

    OpenAIRE

    Cuco, A. P.; Santos, J. I.; Abrantes, N.; Gonçalves, F.; Castro, Bruno B.

    2017-01-01

    Given the importance of pollutant effects on host-parasite relationships and disease spread, the main goal of this study was to assess the influence of different exposure scenarios for the fungicide tebuconazole (concentration × timing of application) on a Daphnia-microparasitic yeast experimental system. Previous results had demonstrated that tebuconazole is able to suppress Metschnikowia bicuspidata infection at ecologically-relevant concentrations; here, we aimed to obtain an understanding...

  13. Strong positive effects of termites on savanna bird abundance and diversity are amplified by large herbivore exclusion

    OpenAIRE

    Moe, Stein R.; Eldegard, Katrine; Rannestad, Ole Tobias; Okullo, Paul; Lindtjørn, Ommund; Støen, Ole Gunnar; Dale, Svein

    2017-01-01

    Abstract Vast areas of the African savanna landscapes are characterized by tree‐covered Macrotermes termite mounds embedded within a relatively open savanna matrix. In concert with termites, large herbivores are important determinants of savanna woody vegetation cover. The relative cover of woody species has considerable effects on savanna function. Despite the potentially important ecological relationships between termite mounds, woody plants, large herbivores, and birds, these associations ...

  14. Neuromodulation to the Rescue: Compensation of Temperature-Induced Breakdown of Rhythmic Motor Patterns via Extrinsic Neuromodulatory Input.

    Directory of Open Access Journals (Sweden)

    Carola Städele

    Full Text Available Stable rhythmic neural activity depends on the well-coordinated interplay of synaptic and cell-intrinsic conductances. Since all biophysical processes are temperature dependent, this interplay is challenged during temperature fluctuations. How the nervous system remains functional during temperature perturbations remains mostly unknown. We present a hitherto unknown mechanism of how temperature-induced changes in neural networks are compensated by changing their neuromodulatory state: activation of neuromodulatory pathways establishes a dynamic coregulation of synaptic and intrinsic conductances with opposing effects on neuronal activity when temperature changes, hence rescuing neuronal activity. Using the well-studied gastric mill pattern generator of the crab, we show that modest temperature increase can abolish rhythmic activity in isolated neural circuits due to increased leak currents in rhythm-generating neurons. Dynamic clamp-mediated addition of leak currents was sufficient to stop neuronal oscillations at low temperatures, and subtraction of additional leak currents at elevated temperatures was sufficient to rescue the rhythm. Despite the apparent sensitivity of the isolated nervous system to temperature fluctuations, the rhythm could be stabilized by activating extrinsic neuromodulatory inputs from descending projection neurons, a strategy that we indeed found to be implemented in intact animals. In the isolated nervous system, temperature compensation was achieved by stronger extrinsic neuromodulatory input from projection neurons or by augmenting projection neuron influence via bath application of the peptide cotransmitter Cancer borealis tachykinin-related peptide Ia (CabTRP Ia. CabTRP Ia activates the modulator-induced current IMI (a nonlinear voltage-gated inward current that effectively acted as a negative leak current and counterbalanced the temperature-induced leak to rescue neuronal oscillations. Computational modelling

  15. Beyond the Big Five: the role of extrinsic life aspirations in compulsive buying.

    Science.gov (United States)

    Otero-López, José M; Villardefrancos Pol, Estíbaliz; Castro Bolaño, Cristina

    2017-11-01

    The integration of units of differing natures which are found in different parts of some multilevel personality models is one of the most thought-provoking paths in contemporary research. In the field of compulsive buying, little is known about the interrelationships between the comparative and stable units such as personality traits (basic tendencies or Level I units) and goals (a kind of middle-level unit) which are more related to motivational processes and intentions governing people’s behavior. Self-reporting measures of compulsive buying, Big Five personality traits, and extrinsic life aspirations were administered to a general population sample consisting of 2,159 participants aged 15 to 65 (48.1% males; Mage= 35.4, SD= 13.24). Our results confirmed statistically significant associations with compulsive buying for the traits as well as the extrinsic goals. Furthermore, an important relationship between both levels in personality – traits vs . extrinsic life aspirations – was found. Finally, extrinsic life aspirations (specially, image, popularity, and conformity) contribute to the potentiation of the prediction of compulsive buying beyond the Five Factor Model. Current findings emphasize the advisability of considering both levels in personality, traits and middle-level units like life aspirations, not only in the prediction of compulsive buying, but also as potential targets for preventive and treatment programs.

  16. The fragmented self : imbalance between intrinsic and extrinsic self-networks in psychotic disorders

    NARCIS (Netherlands)

    Ebisch, Sjoerd J. H.; Aleman, Andre

    Self-disturbances are among the core features of schizophrenia and related psychotic disorders. The basic structure of the self could depend on the balance between intrinsic and extrinsic self-processing. We discuss studies on self-related processing in psychotic disorders that provide converging

  17. A family with extrinsic allergic alveolitis caused by wild city pigeons: A case report

    NARCIS (Netherlands)

    G.J. du Marchie Sarvaas; P.J.F.M. Merkus (Peter); J.C. de Jongste (Johan)

    2000-01-01

    textabstractWe describe a family in which the mother died of unresolved lung disease and whose 5 children, some of whom had previous signs of asthma, were subsequently affected by extrinsic allergic alveolitis caused by contact with wild city pigeon antigens. The children

  18. Extrinsic vs intrinsic labeling of the calcium in whole-wheat flour.

    Science.gov (United States)

    Weaver, C M; Heaney, R P; Martin, B R; Fitzsimmons, M L

    1992-02-01

    Fractional absorption of calcium from bread made either from intrinsically or extrinsically labeled whole-wheat flour was compared in 11 healthy adult women. The intrinsic label was provided by 45Ca injected individually into stems of wheat plants during growth. The extrinsic tag was introduced by adding 45Ca to unlabeled flour via the water used in dough making. The two labeled breads were tested in a randomized crossover design using a standardized breakfast administered after an overnight fast. Approximately 80 g labeled bread was consumed by each subject, providing a total calcium load of 13.3 mg. Fractional absorption from the intrinsically labeled bread averaged 0.812 +/- 0.130 (mean +/- SE) and from the extrinsically labeled bread 0.792 +/- 0.113. The mean difference, within subject, was only 0.025 +/- 0.016 and was not significantly different from zero. Extrinsic labeling of the calcium of whole-wheat flour results in a degree of labeling homogeneity equivalent to that of intrinsic labeling, at least for a leavened bread product.

  19. Zooming in and out: scale dependence of extrinsic and intrinsic factors affecting salt marsh erosion

    NARCIS (Netherlands)

    Wang, H.; van der Wal, D.; Li, X.; van Belzen, J.; Herman, P.M.J.; Hu, Z.; Ge, Z.; Zhang, L.; Bouma, T.J.

    2017-01-01

    Salt marshes are valuable ecosystems that provide important ecosystem services. Given the global scale of marsh loss due to climate change and coastal squeeze, there is a pressing need to identify the critical extrinsic (wind exposure and foreshore morphology) and intrinsic factors (soil and

  20. Students' Extrinsic and Intrinsic Motivation Level and Its Relationship with Their Mathematics Achievement

    Science.gov (United States)

    Acar Güvendir, Meltem

    2016-01-01

    This study focused on the extrinsic and intrinsic motivation levels of eighth grade students and its relationship with their mathematical achievement. The participants of the study included 6,829 students who took TIMSS in 2011 and 239 mathematics teachers. The data obtained from the student and teacher questionnaires that are included in the…

  1. Intrinsic and Extrinsic Reading Motivation as Predictors of Reading Literacy: A Longitudinal Study

    Science.gov (United States)

    Becker, Michael; McElvany, Nele; Kortenbruck, Marthe

    2010-01-01

    The purpose in this study was to examine the longitudinal relationships of intrinsic and extrinsic motivation with reading literacy development. In particular, the authors (a) investigated reading amount as mediator between motivation and reading literacy and (b) probed for bidirectional relationships between reading motivation and reading…

  2. Promoting Intrinsic and Extrinsic Motivation among Chemistry Students Using Computer-Assisted Instruction

    Science.gov (United States)

    Gambari, Isiaka A.; Gbodi, Bimpe E.; Olakanmi, Eyitao U.; Abalaka, Eneojo N.

    2016-01-01

    The role of computer-assisted instruction in promoting intrinsic and extrinsic motivation among Nigerian secondary school chemistry students was investigated in this study. The study employed two modes of computer-assisted instruction (computer simulation instruction and computer tutorial instructional packages) and two levels of gender (male and…

  3. Intrinsic and Extrinsic Motivation and Attitudes toward Professional Continuing Education: Implications for the Counselors.

    Science.gov (United States)

    Drummond, Robert J.; Croll, James C.

    1983-01-01

    Surveyed 3,266 bankers enrolled in a continuing education program to examine differences in motivation. Results showed the largest group listed future advancement as an intrinsic motivational factor. Those in the extrinsic group listed personal growth as a motivator. Counseling strategies to increase employee self-confidence were also discussed.…

  4. How Does Intrinsic and Extrinsic Motivation Drive Performance Culture in Organizations?

    Science.gov (United States)

    Turner, Arielle

    2017-01-01

    The performance culture of an organization is impacted by the motivation of an organization's employee. Determining whether or not an employee's motivation is intrinsic or extrinsic is helpful for organizations to see what is more of a drive in their performance. The following article reviews literature on the subject of employee motivation to…

  5. Profiles of Intrinsic and Extrinsic Motivations in Elementary School: A Longitudinal Analysis

    Science.gov (United States)

    Corpus, Jennifer Henderlong; Wormington, Stephanie V.

    2014-01-01

    The authors used a person-centered, longitudinal approach to identify and evaluate naturally occurring combinations of intrinsic and extrinsic motivations among 490 third- through fifth-grade students. Cluster analysis revealed 3 groups, characterized by high levels of both motivations ("high quantity"): high intrinsic motivation but low…

  6. Intrinsic Motivation, Extrinsic Motivation, and Academic Achievement among Indian Adolescents in Canada and India

    Science.gov (United States)

    Areepattamannil, Shaljan; Freeman, John G.; Klinger, Don A.

    2011-01-01

    The purpose of the present study was to examine the relationships among intrinsic motivation, extrinsic motivation, and academic achievement for the Indian immigrant adolescents in Canada in comparison to their counterparts in India. Descriptive discriminant analysis indicated that the Indian immigrant adolescents in Canada had higher intrinsic…

  7. First principles studies of extrinsic and intrinsic defects in boron nitride nanotubes

    CSIR Research Space (South Africa)

    Mashapa, MG

    2012-10-01

    Full Text Available -1 Journal of Nanoscience and Nanotechnology 2012/ Vol. 12, 7807?7814 First Principles Studies of Extrinsic and Intrinsic Defects in Boron Nitride Nanotubes M. G. Mashapa 1, 2, ?, N. Chetty1, and S. Sinha Ray2, 3 1Physics Department, University...

  8. Detection of in-plane displacements of acoustic wave fields using extrinsic Fizeau fiber interferometric sensors

    Science.gov (United States)

    Dhawan, R.; Gunther, M. F.; Claus, R. O.

    1991-01-01

    Quantitative measurements of the in-plane particle displacement components of ultrasonic surface acoustic wave fields using extrinsic Fizeau fiber interferometric (EFFI) sensors are reported. Wave propagation in materials and the fiber sensor elements are briefly discussed. Calibrated experimental results obtained for simulated acoustic emission events on homogeneous metal test specimens are reported and compared to previous results obtained using piezoelectric transducers.

  9. The fragmented self: imbalance between intrinsic and extrinsic self-networks in psychotic disorders.

    Science.gov (United States)

    Ebisch, Sjoerd J H; Aleman, André

    2016-08-01

    Self-disturbances are among the core features of schizophrenia and related psychotic disorders. The basic structure of the self could depend on the balance between intrinsic and extrinsic self-processing. We discuss studies on self-related processing in psychotic disorders that provide converging evidence for disrupted communication between neural networks subserving the so-called intrinsic self and extrinsic self. This disruption might be mainly caused by impaired integrity of key brain hubs. The intrinsic self has been associated with cortical midline structures involved in self-referential processing, autobiographical memory, and emotional evaluation. Additionally, we highlight central aspects of the extrinsic self in its interaction with the environment using sensorimotor networks, including self-experience in sensation and actions. A deficient relationship between these self-aspects because of disrupted between-network interactions offers a framework to explain core clinical features of psychotic disorders. In particular, we show how relative isolation and reduced modularity of networks subserving intrinsic and extrinsic self-processing might trigger the emergence of hallucinations and delusions, and why patients with psychosis typically have difficulties with self-other relationships and do not recognise mental problems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Further Examining the American Dream: Differential Correlates of Intrinsic and Extrinsic Goals.

    Science.gov (United States)

    Kasser, Tim; Ryan, Richard M.

    1996-01-01

    In a sample of adult subjects (Study One), the relative importance and efficacy of extrinsic aspirations for financial success, an appealing appearance, and social recognition were associated with lower vitality and self-actualization and more physical symptoms. Study Two replicated these findings in a sample of college students. (JPS)

  11. The extrinsic affective Simon task as an instrument for indirect assessment of prejudice

    NARCIS (Netherlands)

    Degner, J.; Wentura, D.

    2008-01-01

    We report one study that explored the applicability of the Extrinsic Affective Simon Task (EAST) as an indirect measure of prejudice. The EAST detected known differences in reactions revealing that a Turkish outgroup was spontaneously evaluated more negatively than the German ingroup. More

  12. Extrinsic Motivation as Correlates of Work Attitude of the Nigerian Police Force: Implications for Counselling

    Science.gov (United States)

    Igun, Sylvester Nosakhare

    2008-01-01

    The study examined Extrinsic motivation as correlates of work attitude of the Nigeria Police Force and its implications for counselling. 300 Police personnel were selected by random sampling technique from six departments that make up police force Headquarters, Abuja. The personnel were selected from each department using simple sampling…

  13. The efficacy of two prototype chewing gums for the removal of extrinsic tooth stain

    NARCIS (Netherlands)

    Ozcan, M; Kulak, Y; Kazazoglu, E

    Aim: To compare the potential efficacy of two prototype chewing gums in extrinsic stain removal on natural teeth. Setting: Dental school clinics. Design: Double-blind, two groups, parallel design. Participants: 76 adult volunteers (32m, 44f, mean age: 20.6 years old). Methods: Oral hard and soft

  14. Indirect Correspondence-Based Robust Extrinsic Calibration of LiDAR and Camera

    Directory of Open Access Journals (Sweden)

    Sungdae Sim

    2016-06-01

    Full Text Available LiDAR and cameras have been broadly utilized in computer vision and autonomous vehicle applications. However, in order to convert data between the local coordinate systems, we must estimate the rigid body transformation between the sensors. In this paper, we propose a robust extrinsic calibration algorithm that can be implemented easily and has small calibration error. The extrinsic calibration parameters are estimated by minimizing the distance between corresponding features projected onto the image plane. The features are edge and centerline features on a v-shaped calibration target. The proposed algorithm contributes two ways to improve the calibration accuracy. First, we use different weights to distance between a point and a line feature according to the correspondence accuracy of the features. Second, we apply a penalizing function to exclude the influence of outliers in the calibration datasets. Additionally, based on our robust calibration approach for a single LiDAR-camera pair, we introduce a joint calibration that estimates the extrinsic parameters of multiple sensors at once by minimizing one objective function with loop closing constraints. We conduct several experiments to evaluate the performance of our extrinsic calibration algorithm. The experimental results show that our calibration method has better performance than the other approaches.

  15. ESTIMATION OF INTRINSIC AND EXTRINSIC ENVIRONMENT FACTORS OF AGE-RELATED TOOTH COLOUR CHANGES

    Czech Academy of Sciences Publication Activity Database

    Hyšpler, P.; Jezbera, D.; Fürst, T.; Mikšík, Ivan; Waclawek, M.

    2010-01-01

    Roč. 17, č. 4 (2010), s. 515-525 ISSN 1898-6196 Institutional research plan: CEZ:AV0Z50110509 Keywords : age-related colour changes of teeth * intrinsic and extrinsic factors * 3D mathematical regression models * estimation of real age Subject RIV: ED - Physiology Impact factor: 0.294, year: 2010

  16. Scaling up the extrinsic curvature in asymptotically flat gravitational initial data: generating trapped surfaces

    International Nuclear Information System (INIS)

    Bai, Shan; Murchadha, Niall Ó

    2013-01-01

    The existence of the initial value constraints means that specifying initial data for the Einstein equations is non-trivial. The standard method of constructing initial data in the asymptotically flat case is to choose an asymptotically flat 3-metric and a transverse-tracefree (TT) tensor on it. One can find a conformal transformation that maps these data into solutions of the constraints. In particular, the TT tensor becomes the extrinsic curvature of the 3-slice. We wish to understand how the physical solution changes as the free data is changed. In this paper we investigate an especially simple change: we multiply the TT tensor by a large constant. One might assume that this corresponds to pumping up the extrinsic curvature in the physical initial data. Unexpectedly, we show that, while the conformal factor monotonically increases, the physical extrinsic curvature decreases. The increase in the conformal factor however means that the physical volume increases in such a way that the ADM mass become unboundedly large. In turn, the blow-up of the mass combined with the control we have on the extrinsic curvature allows us to show that trapped surfaces, i.e. surfaces that are simultaneously future and past trapped, appear in the physical initial data. (paper)

  17. Strong room-temperature negative transconductance in an axial Si/Ge hetero-nanowire tunneling field-effect transistor

    Science.gov (United States)

    Zhang, Peng; Le, Son T.; Hou, Xiaoxiao; Zaslavsky, A.; Perea, Daniel E.; Dayeh, Shadi A.; Picraux, S. T.

    2014-08-01

    We report on room-temperature negative transconductance (NTC) in axial Si/Ge hetero-nanowire tunneling field-effect transistors. The NTC produces a current peak-to-valley ratio >45, a high value for a Si-based device. We characterize the NTC over a range of gate VG and drain VD voltages, finding that NTC persists down to VD = -50 mV. The physical mechanism responsible for the NTC is the VG-induced depletion in the p-Ge section that eventually reduces the maximum electric field that triggers the tunneling ID, as confirmed via three-dimensional (3D) technology computer-aided design simulations.

  18. Strong Rashba-Edelstein Effect-Induced Spin–Orbit Torques in Monolayer Transition Metal Dichalcogenide/Ferromagnet Bilayers

    KAUST Repository

    Shao, Qiming

    2016-11-18

    The electronic and optoelectronic properties of two-dimensional materials have been extensively explored in graphene and layered transition metal dichalcogenides (TMDs). Spintronics in these two-dimensional materials could provide novel opportunities for future electronics, for example, efficient generation of spin current, which should enable the efficient manipulation of magnetic elements. So far, the quantitative determination of charge current-induced spin current and spin-orbit torques (SOTs) on the magnetic layer adjacent to two-dimensional materials is still lacking. Here, we report a large SOT generated by current-induced spin accumulation through the Rashba-Edelstein effect in the composites of monolayer TMD (MoS or WSe)/CoFeB bilayer. The effective spin conductivity corresponding to the SOT turns out to be almost temperature-independent. Our results suggest that the charge-spin conversion in the chemical vapor deposition-grown large-scale monolayer TMDs could potentially lead to high energy efficiency for magnetization reversal and convenient device integration for future spintronics based on two-dimensional materials.

  19. Re-evaluation of the macroseismic effects produced by the March 4, 1977, strong Vrancea earthquake in Romanian territory

    Directory of Open Access Journals (Sweden)

    Aurelian Pantea

    2013-04-01

    Full Text Available In this paper, the macroseismic effects of the subcrustal earthquake in Vrancea (Romania that occurred on March 4, 1977, have been re-evaluated. This was the second strongest seismic event that occurred in this area during the twentieth century, following the event that happened on November 10, 1940. It is thus of importance for our understanding of the seismicity of the Vrancea zone. The earthquake was felt over a large area, which included the territories of the neighboring states, and it produced major damage. Due to its effects, macroseismic studies were developed by Romanian researchers soon after its occurrence, with foreign scientists also involved, such as Medvedev, the founder of the Medvedev-Sponheuer-Karnik (MSK seismic intensity scale. The original macroseismic questionnaires were re-examined, to take into account the recommendations for intensity assessments according to the MSK-64 macroseismic scale used in Romania. After the re-evaluation of the macroseismic field of this earthquake, the intensity dataset was obtained for 1,620 sites in Romanian territory. The re-evaluation was necessary as it has confirmed that the previous macroseismic map was underestimated. On this new map, only the intensity data points are plotted, without tracing the isoseismals.

  20. Differential Contributions of Intrinsic and Extrinsic Pathways to Thrombin Generation in Adult, Maternal and Cord Plasma Samples.

    Directory of Open Access Journals (Sweden)

    Nicklaus T Rice

    Full Text Available Thrombin generation (TG is a pivotal process in achieving hemostasis. Coagulation profiles during pregnancy and early neonatal period are different from that of normal (non-pregnant adults. In this ex vivo study, the differences in TG in maternal and cord plasma relative to normal adult plasma were studied.Twenty consented pregnant women and ten consented healthy adults were included in the study. Maternal and cord blood samples were collected at the time of delivery. Platelet-poor plasma was isolated for the measurement of TG. In some samples, anti-FIXa aptamer, RB006, or a TFPI inhibitor, BAX499 were added to elucidate the contribution of intrinsic and extrinsic pathway to TG. Additionally, procoagulant and inhibitor levels were measured in maternal and cord plasma, and these values were used to mathematically simulate TG.Peak TG was increased in maternal plasma (393.6±57.9 nM compared to adult and cord samples (323.2±38.9 nM and 209.9±29.5 nM, respectively. Inhibitory effects of RB006 on TG were less robust in maternal or cord plasma (52% vs. 12% respectively than in adult plasma (81%. Likewise the effectiveness of BAX499 as represented by the increase in peak TG was much greater in adult (21% than in maternal (10% or cord plasma (12%. Further, BAX499 was more effective in reversing RB006 in adult plasma than in maternal or cord plasma. Ex vivo data were reproducible with the results of the mathematical simulation of TG.Normal parturient plasma shows a large intrinsic pathway reserve for TG compared to adult and cord plasma, while TG in cord plasma is sustained by extrinsic pathway, and low levels of TFPI and AT.

  1. Roles of the quadrupole interaction and of the quadratic stark effect in spectral lines from plasmas interacting with a strong quasimonochromatic electric field

    Czech Academy of Sciences Publication Activity Database

    Sauvan, P.; Dalimier, E.; Riconda, C.; Oks, E.; Renner, Oldřich; Weber, S.

    2010-01-01

    Roč. 1, č. 2 (2010), s. 123-128 ISSN 2229-3159 R&D Projects: GA MŠk(CZ) LC528 Institutional research plan: CEZ:AV0Z10100523 Keywords : laser-plasma interaction * PIC plasma model ing * strong quasimonochromatic electric fields * x-ray line broadening * stark effect * floquet theory Subject RIV: BH - Optics, Masers, Lasers http://www.auburn.edu/academic/cosam/departments/physics/iramp/1_2/sauvan_et_al.pdf

  2. CO J = 6-5 IN Arp 220: STRONG EFFECTS OF DUST ON HIGH-J CO LINES

    International Nuclear Information System (INIS)

    Papadopoulos, Padeli P.; Isaak, Kate; Van der Werf, Paul

    2010-01-01

    We report new single dish CO J = 6-5 line observations for the archetypal Ultra Luminous Infrared Galaxy (ULIRG) Arp 220 with the James Clerk Maxwell Telescope atop Mauna Kea in Hawaii. The J = 6-5 line is found to be faint, with brightness temperature ratios (6-5)/(1-0), (6-5)/(3-2) of R 65/10 = 0.080 ± 0.017 and R 65/32 = 0.082 ± 0.019, suggesting very low excitation conditions that cannot be reconciled with the warm and very dense molecular gas present in one of the most extreme starbursts in the local universe. We find that an optically thick dust continuum, with τ(ν ∼> 350 GHz) ∼> 1 for the bulk of the warm dust and gas in Arp 220, submerges this line to an almost black body curve, reducing its flux, and affecting its CO spectral line energy distribution at high frequencies. This also resolves the C + line deficiency in this object, first observed by Infrared Space Observatory: the near absence of that line is a dust optical depth effect, not a dense photodissociation region phenomenon. Finally, we briefly comment on the possibility of such extreme interstellar medium (ISM) states in other ULIRGs in the distant universe, and their consequences for the diagnostic utility of high frequency molecular and atomic ISM lines in such systems. In the case of Arp 220, we anticipate that the now spaceborne Herschel Space Observatory will find faint high-J CO lines at ν ∼> 690 GHz that would appear as sub-thermally excited with respect to the low-J ones as a result of the effects of dust absorption.

  3. Strong positive effects of termites on savanna bird abundance and diversity are amplified by large herbivore exclusion.

    Science.gov (United States)

    Moe, Stein R; Eldegard, Katrine; Rannestad, Ole Tobias; Okullo, Paul; Lindtjørn, Ommund; Støen, Ole Gunnar; Dale, Svein

    2017-12-01

    Vast areas of the African savanna landscapes are characterized by tree-covered Macrotermes termite mounds embedded within a relatively open savanna matrix. In concert with termites, large herbivores are important determinants of savanna woody vegetation cover. The relative cover of woody species has considerable effects on savanna function. Despite the potentially important ecological relationships between termite mounds, woody plants, large herbivores, and birds, these associations have previously received surprisingly little attention. We experimentally studied the effects of termites and large herbivores on the avian community in Lake Mburo National Park, Uganda, where woody vegetation is essentially limited to termite mounds. Our experiment comprised of four treatments in nine replicates; unfenced termite mounds, fenced mounds (excluding large mammals), unfenced adjacent savanna, and fenced savanna. We recorded species identity, abundance, and behavior of all birds observed on these plots over a two-month period, from late dry until wet season. Birds used termite mounds almost exclusively, with only 3.5% of observations occurring in the treeless intermound savanna matrix. Mean abundance and species richness of birds doubled on fenced (large herbivores excluded) compared to unfenced mounds. Feeding behavior increased when large mammals were excluded from mounds, both in absolute number of observed individuals, and relative to other behaviors. This study documents the fundamental positive impact of Macrotermes termites on bird abundance and diversity in an African savanna. Birds play crucial functional roles in savanna ecosystems, for example, by dispersing fruits or regulating herbivorous insect populations. Thus, the role of birds in savanna dynamics depends on the distribution and abundance of termite mounds.

  4. Survey of strong motion earthquake effects on thermal power plants in California with emphasis on piping systems. Volume 1, Main report

    International Nuclear Information System (INIS)

    Stevenson, J.D.

    1995-11-01

    Since 1982, there has been a major effort expended to evaluate the susceptibility of nuclear Power plant equipment to failure and significant damage during seismic events. This was done by making use of data on the performance of electrical and mechanical equipment in conventional power plants and other similar industrial facilities during strong motion earthquakes. This report is intended as an extension of the seismic experience data collection effort and a compilation of experience data specific to power plant piping and supports designed and constructed US power piping code requirements which have experienced strong motion earthquakes. Eight damaging (Richter Magnitude 7.7 to 5.5) California earthquakes and their effects on 8 power generating facilities in use natural gas and California were reviewed. All of these facilities were visited and evaluated. Seven fossel-fueled (dual use natural gas and oil) and one nuclear fueled plants consisting of a total of 36 individual boiler or reactor units were investigated. Peak horizontal ground accelerations that either had been recorded on site at these facilities or were considered applicable to these power plants on the basis of nearby recordings ranged between 0.20g and 0.5lg with strong motion durations which varied from 3.5 to 15 seconds. Most US nuclear power plants are designed for a safe shutdown earthquake peak ground acceleration equal to 0.20g or less with strong motion durations which vary from 10 to 15 seconds

  5. Propranolol–induced Impairment of Contextual Fear Memory Reconsolidation in Rats: A Similar Effect on Weak and Strong Recent and Remote Memories

    Directory of Open Access Journals (Sweden)

    Fatemeh Taherian

    2014-07-01

    Full Text Available Introduction: Previous studies have demonstrated that the &beta-adrenergic receptor antagonist propranolol impairs fear memory reconsolidation in experimental animals. There are experimental parameters such as the age and the strength of memory that can interact with pharmacological manipulations of memory reconsolidation. In this study, we investigated the ability of the age and the strength of memory to influence the disrupting effects of propranolol on fear memory reconsolidation in rats. Methods: The rats were trained in a contextual fear conditioning using two (weak training or five (strong training footshocks (1mA. Propranolol (10mg/kg injection was immediately followed retrieval of either a one-day recent (weak or strong or 36-day remote (weak or strong contextual fear memories. Results: We found that propranolol induced a long-lasting impairment of subsequent expression of recent and remote memories with either weak or strong strength. We also found no memory recovery after a weak reminder shock. Furthermore, no significant differences were found on the amount of memory deficit induced by propranolol among memories with different age and strength. Discussion: Our data suggest that the efficacy of propranolol in impairing fear memory reconsolidation is not limited to the age or strength of the memory.

  6. Novel experimental methods for investigating high speed friction of titanium-aluminum-vanadium/tool steel interface and dynamic failure of extrinsically toughened DRA composites

    Science.gov (United States)

    Irfan, Mohammad Abdulaziz

    effects the sliding resistance of the interface. The experimental results deduced from the response of the sliding interface to step changes in normal pressure and the applied shear stress reinforce the importance of including frictional memory in the development of rate dependent state variable friction models. The second part of the thesis presents an investigation into the dynamic deformation and failure of extrinsically toughened DRA composites. Experiments were conducted using the split Hopkinson pressure bar to investigate the deformation and flow behavior under dynamic compression loading. A modified Hopkinson bar apparatus was used to explore the dynamic fracture behavior of three different extrinsically toughened DRA composites. The study was paralleled by systematic exploration of the failure modes in each composite. For all the composites evaluated the dynamic crack propagation characteristics of the composites are observed to be strongly dependent on the volume fraction of the ductile phase reinforcement in the composite, the yield stress of the ductile phase reinforcement, the micro-structural arrangement of the ductile phase reinforcements with respect to the notch, and the impact velocity employed in the particular experiment.

  7. 1-Benzyl-2-Phenylbenzimidazole (BPB, a Benzimidazole Derivative, Induces Cell Apoptosis in Human Chondrosarcoma through Intrinsic and Extrinsic Pathways

    Directory of Open Access Journals (Sweden)

    Ju-Fang Liu

    2012-12-01

    Full Text Available In this study, we investigated the anticancer effects of a new benzimidazole derivative, 1-benzyl-2-phenyl -benzimidazole (BPB, in human chondrosarcoma cells. BPB-mediated apoptosis was assessed by the MTT assay and flow cytometry analysis. The in vivo efficacy was examined in a JJ012 xenograft model. Here we found that BPB induced apoptosis in human chondrosarcoma cell lines (JJ012 and SW1353 but not in primary chondrocytes. BPB induced upregulation of Bax, Bad and Bak, downregulation of Bcl-2, Bid and Bcl-XL and dysfunction of mitochondria in chondrosarcoma. In addition, BPB also promoted cytosolic releases AIF and Endo G. Furthermore, it triggered extrinsic death receptor-dependent pathway, which was characterized by activating Fas, FADD and caspase-8. Most importantly, animal studies revealed a dramatic 40% reduction in tumor volume after 21 days of treatment. Thus, BPB may be a novel anticancer agent for the treatment of chondrosarcoma.

  8. Designer thermal switches: the effect of the contact material on instantaneous thermoelectric transport through a strongly interacting quantum dot

    Science.gov (United States)

    Goker, A.; Gedik, E.

    2013-09-01

    We investigate the effect of contact material on the instantaneous thermoelectric response of a quantum dot pushed suddenly into the Kondo regime via a gate voltage using time dependent non-crossing approximation and linear response Onsager relations. We utilize graphene and metal contacts for this purpose. Instantaneous thermopower displays sinusoidal oscillations whose frequency is proportional to the energy separation between the van Hove singularity in the contact density of states and the Fermi level for both cases, regardless of the asymmetry factor at the onset of the Kondo timescale. The amplitude of the oscillations increases with decreasing temperature, saturating around the Kondo temperature. We also calculate the instantaneous figure of merit and show that the oscillations taking place at temperatures above the Kondo temperature are enhanced more than the ones occurring at lower temperatures due to the violation of the Wiedemann-Franz law. Graphene emerges as a more promising electrode candidate than ordinary metals in single electron devices since it can minimize these oscillations.

  9. Intrinsic and extrinsic influences on standard metabolic rates of three species of Australian otariid.

    Science.gov (United States)

    Ladds, Monique A; Slip, David J; Harcourt, Robert G

    2017-01-01

    The study of marine mammal energetics can shed light on how these animals might adapt to changing environments. Their physiological potential to adapt will be influenced by extrinsic factors, such as temperature, and by intrinsic factors, such as sex and reproduction. We measured the standard metabolic rate (SMR) of males and females of three Australian otariid species (two Australian fur seals, three New Zealand fur seals and seven Australian sea lions). Mean SMR ranged from 0.47 to 1.05 l O 2 min -1 , which when adjusted for mass was from 5.33 to 7.44 ml O 2 min -1 kg -1 . We found that Australian sea lion mass-specific SMR (sSMR; in millilitres of oxygen per minute per kilogram) varied little in response to time of year or moult, but was significantly influenced by sex and water temperature. Likewise, sSMR of Australian and New Zealand fur seals was also influenced by sex and water temperature, but also by time of year (pre-moult, moult or post-moult). During the moult, fur seals had significantly higher sSMR than at other times of the year, whereas there was no discernible effect of moult for sea lions. For both groups, females had higher sSMR than males, but sea lions and fur seals showed different responses to changes in water temperature. The sSMR of fur seals increased with increasing water temperature, whereas sSMR of sea lions decreased with increasing water temperature. There were no species differences when comparing animals of the same sex. Our study suggests that fur seals have more flexibility in their physiology than sea lions, perhaps implying that they will be more resilient in a changing environment.

  10. Genetic Modifiers of Cardiovascular Phenotype Caused by Elastin Haploinsufficiency Act by Extrinsic Noncomplementation*

    Science.gov (United States)

    Kozel, Beth A.; Knutsen, Russell H.; Ye, Li; Ciliberto, Christopher H.; Broekelmann, Thomas J.; Mecham, Robert P.

    2011-01-01

    Elastin haploinsufficiency causes the cardiovascular complications associated with Williams-Beuren syndrome and isolated supravalvular aortic stenosis. Significant variability exists in the vascular pathology in these individuals. Using the Eln+/− mouse, we sought to identify the source of this variability. Following outcrossing of C57Bl/6J Eln+/−, two backgrounds were identified whose cardiovascular parameters deviated significantly from the parental strain. F1 progeny of the C57Bl/6J; Eln+/−x129X1/SvJ were more hypertensive and their arteries less compliant. In contrast, Eln+/− animals crossed to DBA/2J were protected from the pathologic changes associated with elastin insufficiency. Among the crosses, aortic elastin and collagen content did not correlate with quantitative vasculopathy traits. Quantitative trait locus analysis performed on F2 C57; Eln+/−x129 intercrosses identified highly significant peaks on chromosome 1 (LOD 9.7) for systolic blood pressure and on chromosome 9 (LOD 8.7) for aortic diameter. Additional peaks were identified that affect only Eln+/−, including a region upstream of Eln on chromosome 5 (LOD 4.5). Bioinformatic analysis of the quantitative trait locus peaks revealed several interesting candidates, including Ren1, Ncf1, and Nos1; genes whose functions are unrelated to elastic fiber assembly, but whose effects may synergize with elastin insufficiency to predispose to hypertension and stiffer blood vessels. Real time RT-PCR studies show background-specific increased expression of Ncf1 (a subunit of the NOX2 NAPDH oxidase) that parallel the presence of increased oxidative stress in Eln+/− aortas. This finding raises the possibility that polymorphisms in genes affecting the generation of reactive oxygen species alter cardiovascular function in individuals with elastin haploinsufficiency through extrinsic noncomplementation. PMID:22049077

  11. Genetic modifiers of cardiovascular phenotype caused by elastin haploinsufficiency act by extrinsic noncomplementation.

    Science.gov (United States)

    Kozel, Beth A; Knutsen, Russell H; Ye, Li; Ciliberto, Christopher H; Broekelmann, Thomas J; Mecham, Robert P

    2011-12-30

    Elastin haploinsufficiency causes the cardiovascular complications associated with Williams-Beuren syndrome and isolated supravalvular aortic stenosis. Significant variability exists in the vascular pathology in these individuals. Using the Eln(+/-) mouse, we sought to identify the source of this variability. Following outcrossing of C57Bl/6J Eln(+/-), two backgrounds were identified whose cardiovascular parameters deviated significantly from the parental strain. F1 progeny of the C57Bl/6J; Eln(+/-)x129X1/SvJ were more hypertensive and their arteries less compliant. In contrast, Eln(+/-) animals crossed to DBA/2J were protected from the pathologic changes associated with elastin insufficiency. Among the crosses, aortic elastin and collagen content did not correlate with quantitative vasculopathy traits. Quantitative trait locus analysis performed on F2 C57; Eln(+/-)x129 intercrosses identified highly significant peaks on chromosome 1 (LOD 9.7) for systolic blood pressure and on chromosome 9 (LOD 8.7) for aortic diameter. Additional peaks were identified that affect only Eln(+/-), including a region upstream of Eln on chromosome 5 (LOD 4.5). Bioinformatic analysis of the quantitative trait locus peaks revealed several interesting candidates, including Ren1, Ncf1, and Nos1; genes whose functions are unrelated to elastic fiber assembly, but whose effects may synergize with elastin insufficiency to predispose to hypertension and stiffer blood vessels. Real time RT-PCR studies show background-specific increased expression of Ncf1 (a subunit of the NOX2 NAPDH oxidase) that parallel the presence of increased oxidative stress in Eln(+/-) aortas. This finding raises the possibility that polymorphisms in genes affecting the generation of reactive oxygen species alter cardiovascular function in individuals with elastin haploinsufficiency through extrinsic noncomplementation.

  12. Self-expanding oesophageal metal stents for the palliation of dysphagia due to extrinsic compression

    International Nuclear Information System (INIS)

    Gupta, N.K.; Boylan, C.E.; Razzaq, R.; England, R.E.; Mirra, L.; Martin, D.F.

    1999-01-01

    The role of self-expanding metallic stents is well established in the palliation of oesophageal stenosis and dysphagia due to primary oesophageal malignancy. However, their role in palliation of dysphagia due to external compressive mediastinal malignancies is not well established. The purpose of this study was to assess the efficacy of self-expanding metallic stents in the palliation of dysphagia due to extrinsic oesophageal compression by mediastinal malignancy. Between January 1995 and January 1998, 21 patients with oesophageal compression due to malignant mediastinal tumours underwent oesophageal stent placement for palliation of dysphagia. Complete data were available in 17 patients (10 men and 7 women). The mean age was 63.5 years (range 46-89 years). A total of 19 stents were placed successfully. The dysphagia grade prior to and after oesophageal stent placement was assessed and the complications documented. Of the 17 patients, 16 reported an improvement in dysphagia. The mean dysphagia score improved from 3.1 prior to treatment to 1.3 after treatment. In 1 patient the stent slipped during placement and another stent was placed satisfactorily. Early complications (within 48 h) in the form of mild to moderate retrosternal chest pain occurred in 5 patients. This was treated symptomatically. Late complications (after 48 h) in the form of bolus impaction occurred in 2 patients. This was successfully treated with oesophagoscopy and removal of bolus. In 2 patients the stent was overgrown by tumour and in one of these an additional stent was placed. In 1 patient incomplete closure of a tracheo-oesophageal fistula was observed. There was no procedure- or stent-related mortality. The mean survival time of this group was 2.1 months. Self-expanding metallic stents can be safely and effectively used in the palliation of dysphagia due to external mediastinal malignancies. (orig.)

  13. Broad-Spectrum Antimicrobial Effects of Photocatalysis Using Titanium Dioxide Nanoparticles Are Strongly Potentiated by Addition of Potassium Iodide.

    Science.gov (United States)

    Huang, Ying-Ying; Choi, Hwanjun; Kushida, Yu; Bhayana, Brijesh; Wang, Yuguang; Hamblin, Michael R

    2016-09-01

    Photocatalysis describes the excitation of titanium dioxide nanoparticles (a wide-band gap semiconductor) by UVA light to produce reactive oxygen species (ROS) that can destroy many organic molecules. This photocatalysis process is used for environmental remediation, while antimicrobial photocatalysis can kill many classes of microorganisms and can be used to sterilize water and surfaces and possibly to treat infections. Here we show that addition of the nontoxic inorganic salt potassium iodide to TiO2 (P25) excited by UVA potentiated the killing of Gram-positive bacteria, Gram-negative bacteria, and fungi by up to 6 logs. The microbial killing depended on the concentration of TiO2, the fluence of UVA light, and the concentration of KI (the best effect was at 100 mM). There was formation of long-lived antimicrobial species (probably hypoiodite and iodine) in the reaction mixture (detected by adding bacteria after light), but short-lived antibacterial reactive species (bacteria present during light) produced more killing. Fluorescent probes for ROS (hydroxyl radical and singlet oxygen) were quenched by iodide. Tri-iodide (which has a peak at 350 nm and a blue product with starch) was produced by TiO2-UVA-KI but was much reduced when methicillin-resistant Staphylococcus aureus (MRSA) cells were also present. The model tyrosine substrate N-acetyl tyrosine ethyl ester was iodinated in a light dose-dependent manner. We conclude that UVA-excited TiO2 in the presence of iodide produces reactive iodine intermediates during illumination that kill microbial cells and long-lived oxidized iodine products that kill after light has ended. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  14. Strong and persistent effect on liver fat with a Paleolithic diet during a two-year intervention.

    Science.gov (United States)

    Otten, J; Mellberg, C; Ryberg, M; Sandberg, S; Kullberg, J; Lindahl, B; Larsson, C; Hauksson, J; Olsson, T

    2016-05-01

    Our objective was to investigate changes in liver fat and insulin sensitivity during a 2-year diet intervention. An ad libitum Paleolithic diet (PD) was compared with a conventional low-fat diet (LFD). Seventy healthy, obese, postmenopausal women were randomized to either a PD or a conventional LFD. Diet intakes were ad libitum. Liver fat was measured with proton magnetic resonance spectroscopy. Insulin sensitivity was evaluated with oral glucose tolerance tests and calculated as homeostasis model assessment-insulin resistance (HOMA-IR)/liver insulin resistance (Liver IR) index for hepatic insulin sensitivity and oral glucose insulin sensitivity (OGIS)/Matsuda for peripheral insulin sensitivity. All measurements were performed at 0, 6 and 24 months. Forty-one women completed the examinations for liver fat and were included. Liver fat decreased after 6 months by 64% (95% confidence interval: 54-74%) in the PD group and by 43% (27-59%) in the LFD group (P<0.01 for difference between groups). After 24 months, liver fat decreased 50% (25-75%) in the PD group and 49% (27-71%) in the LFD group. Weight reduction between baseline and 6 months was correlated to liver fat improvement in the LFD group (rs=0.66, P<0.01) but not in the PD group (rs=0.07, P=0.75). Hepatic insulin sensitivity improved during the first 6 months in the PD group (P<0.001 for Liver IR index and HOMA-IR), but deteriorated between 6 and 24 months without association with liver fat changes. A PD with ad libitum intake had a significant and persistent effect on liver fat and differed significantly from a conventional LFD at 6 months. This difference may be due to food quality, for example, a higher content of mono- and polyunsaturated fatty acids in the PD. Changes in liver fat did not associate with alterations in insulin sensitivity.

  15. Preoperative low muscle mass has a strong negative effect on pulmonary function in patients undergoing living donor liver transplantation.

    Science.gov (United States)

    Shirai, Hisaya; Kaido, Toshimi; Hamaguchi, Yuhei; Yao, Siyuan; Kobayashi, Atsushi; Okumura, Shinya; Kamo, Naoko; Yagi, Shintaro; Okajima, Hideaki; Uemoto, Shinji

    2018-01-01

    This study investigated the effect of preoperative sarcopenia on cardiopulmonary function in patients undergoing living donor liver transplantation (LDLT). A retrospective analysis was performed of 207 patients who underwent LDLT between January 2008 and April 2015. The quantity and quality of skeletal muscle were evaluated by the psoas muscle mass index (PMI) and intramuscular adipose tissue content (IMAC), respectively, using preoperative computed tomography imaging. The correlations between preoperative cardiopulmonary function and sarcopenic factors (PMI, IMAC, and grip strength [GS]) were examined. Moreover, overall survival (OS) rates according to preoperative pulmonary function and risk factors were analyzed. No significant differences were found between ejection fraction (EF) and these sarcopenic factors. In contrast, preoperative vital capacity (VC) and forced expiratory volume (FEV) 1.0 were significantly correlated with PMI (P < 0.001, P < 0.001), IMAC (P = 0.024, P = 0.013), and GS (P = 0.006, P = 0.033) in males. Preoperative VC and FEV1.0 were significantly correlated with IMAC (P = 0.002, P = 0.001) and GS (P = 0.002, P = 0.001) in females. Moreover, %VC, VC, and FEV1.0 in the preoperative low muscle mass group were significantly lower than in the normal muscle mass group (P = 0.004, P < 0.001, P < 0.001, respectively) in males. Multivariate analysis revealed that preoperative low PMI and preoperative restrictive ventilatory impairment were independent risk factors (P = 0.046 and P = 0.014, respectively). Preoperative low muscle mass was closely involved with pulmonary dysfunction in patients undergoing LDLT. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Strong effect of SNP rs4988300 of the LRP5 gene on bone phenotype of Caucasian postmenopausal women.

    Science.gov (United States)

    Horváth, Péter; Balla, Bernadett; Kósa, János P; Tóbiás, Bálint; Szili, Balázs; Kirschner, Gyöngyi; Győri, Gabriella; Kató, Karina; Lakatos, Péter; Takács, István

    2016-01-01

    The purpose of this study was to identify relationships between single nucleotide polymorphisms (SNPs) in the genes of the Wnt pathway and bone mineral density (BMD) of postmenopausal women. We chose this pathway due to its importance in bone metabolism that was underlined in several studies. DNA samples of 932 Hungarian postmenopausal women were studied. First, their BMD values at different sites (spine, total hip) were measured, using a Lunar Prodigy DXA scanner. Thereafter, T-score values and the patients' body mass indices (BMIs) were calculated, while information about the fracture history of the sample population was also collected. We genotyped nine SNPs of the following three genes: LRP5, GPR177, and SP7, using a Sequenom MassARRAY Analyzer 4 instrument. The genomic DNA samples used for genotyping were extracted from the buccal mucosa of the subjects. Statistical analyses were carried out using the SPSS 21 and R package. The results of this analysis showed a significant association between SNP rs4988300 of the LRP5 gene and total hip BMD values. We could not reveal any associations between the markers of GPR177, SP7, and bone phenotypes. We found no effect of these genotypes on fracture risk. We could demonstrate a significant gene-gene interaction between two SNPs of LRP5 (rs4988300 and rs634008, p = 0.009) which was lost after Bonferroni correction. We could firmly demonstrate a significant association between rs4988300 of the LRP5 gene and bone density of the hip on the largest homogeneous postmenopausal study group analyzed to date. Our finding corroborates the relationship between LRP5 genotype and bone phenotype in postmenopausal women, however, the complete mechanism of this relationship requires further investigations.

  17. Strong effect of copper(II) coordination on antiproliferative activity of thiosemicarbazone-piperazine and thiosemicarbazone-morpholine hybrids.

    Science.gov (United States)

    Bacher, Felix; Dömötör, Orsolya; Chugunova, Anastasia; Nagy, Nóra V; Filipović, Lana; Radulović, Siniša; Enyedy, Éva A; Arion, Vladimir B

    2015-05-21

    In this study, 2-formylpyridine thiosemicarbazones and three different heterocyclic pharmacophores were combined to prepare thiosemicarbazone–piperazine mPip-FTSC (HL1) and mPip-dm-FTSC (HL2), thiosemicarbazone–morpholine Morph-FTSC (HL3) and Morph-dm-FTSC (HL4), thiosemicarbazone–methylpyrrole-2-carboxylate hybrids mPyrr-FTSC (HL5) and mPyrr-dm-FTSC (HL6) as well as their copper(II) complexes [CuCl(mPipH-FTSC-H)]Cl (1 + H)Cl, [CuCl(mPipH-dm-FTSC-H)]Cl (2 + H)Cl, [CuCl(Morph-FTSC-H)] (3), [CuCl(Morph-dm-FTSC-H)] (4), [CuCl(mPyrr-FTSC-H)(H2O)] (5) and [CuCl(mPyrr-dm-FTSC-H)(H2O)] (6). The substances were characterized by elemental analysis, one- and two-dimensional NMR spectroscopy (HL1–HL6), ESI mass spectrometry, IR and UV–vis spectroscopy and single crystal X-ray diffraction (1–5). All compounds were prepared in an effort to generate potential antitumor agents with an improved therapeutic index. In addition, the effect of structural alterations with organic hybrids on aqueous solubility and copper(II) coordination ability was investigated. Complexation of ligands HL2 and HL4 with copper(II) was studied in aqueous solution by pH-potentiometry, UV–vis spectrophotometry and EPR spectroscopy. Proton dissociation processes of HL2 and HL4 were also characterized in detail and microscopic constants for the Z/E isomers were determined. While the hybrids HL5, HL6 and their copper(II) complexes 5 and 6 proved to be insoluble in aqueous solution, precluding antiproliferative activity studies, the thiosemicarbazone–piperazine and thiosemicarbazone–morpholine hybrids HL1–HL4, as well as copper(II) complexes 1–4 were soluble in water enabling cytotoxicity assays. Interestingly, the metal-free hybrids showed very low or even a lack of cytotoxicity (IC50 values > 300 μM) in two human cancer cell lines HeLa (cervical carcinoma) and A549 (alveolar basal adenocarcinoma), whereas their copper(II) complexes were cytotoxic showing IC50 values from 25.5 to 65.1

  18. Electric quadrupole moments and strong interaction effects in pionic atoms of 165Ho, 175Lu, 176Lu, 179Hf and 181Ta

    International Nuclear Information System (INIS)

    Olaniyi, B.; Shor, A.; Cheng, S.C.; Dugan, G.; Wu, C.S.

    1981-05-01

    The effective quadrupole moments Q sub(eff) of the nuclei of 165 Ho, 175 Lu, 176 Lu, 179 Hf and 181 Ta were accurately measured by detecting the pionic atom 5g-4f x-rays of the elements. The spectroscopic quadrupole moments, Q sub(spec), were obtained by correcting Q sub(eff) for nuclear finite size effect, distortion of the pion wave function by the pion-nucleus strong interaction, and contribution to the energy level splittings by the strong interaction. The intrinsic quadrupole moments, Q 0 , were obtained by projecting Q sub(spec) into the frame of reference fixed on the nucleus. The shift, epsilon 0 , and broadening, GAMMA 0 , of the 4f energy level due to the strong interactions between the pion and the nucleons for all the elements were also measured. Theoretical values of epsilon 0 and GAMMA 0 were calculated and compared to the experimental values. The measured values of Q 0 were compared with the existing results in muonic and pionic atoms. The measured values of epsilon 0 and GAMMA 0 were also compared with existing values. (auth)

  19. Work-related pain in extrinsic finger extensor musculature of instrumentalists is associated with intracellular pH compartmentation during exercise.

    Directory of Open Access Journals (Sweden)

    Angel Moreno-Torres

    Full Text Available BACKGROUND: Although non-specific pain in the upper limb muscles of workers engaged in mild repetitive tasks is a common occupational health problem, much is unknown about the associated structural and biochemical changes. In this study, we compared the muscle energy metabolism of the extrinsic finger extensor musculature in instrumentalists suffering from work-related pain with that of healthy control instrumentalists using non-invasive phosphorus magnetic resonance spectroscopy ((31P-MRS. We hypothesize that the affected muscles will show alterations related with an impaired energy metabolism. METHODOLOGY/PRINCIPAL FINDINGS: We studied 19 volunteer instrumentalists (11 subjects with work-related pain affecting the extrinsic finger extensor musculature and 8 healthy controls. We used (31P-MRS to find deviations from the expected metabolic response to exercise in phosphocreatine (PCr, inorganic phosphate (Pi, Pi/PCr ratio and intracellular pH kinetics. We observed a reduced finger extensor exercise tolerance in instrumentalists with myalgia, an intracellular pH compartmentation in the form of neutral and acid compartments, as detected by Pi peak splitting in (31P-MRS spectra, predominantly in myalgic muscles, and a strong association of this pattern with the condition. CONCLUSIONS/SIGNIFICANCE: Work-related pain in the finger extrinsic extensor muscles is associated with intracellular pH compartmentation during exercise, non-invasively detectable by (31P-MRS and consistent with the simultaneous energy production by oxidative metabolism and glycolysis. We speculate that a deficit in energy production by oxidative pathways may exist in the affected muscles. Two possible explanations for this would be the partial and/or local reduction of blood supply and the reduction of the muscle oxidative capacity itself.

  20. <strong>Neuroeconomics and Human Resource Developmentstrong>/>

    DEFF Research Database (Denmark)

    Larsen, Torben

    2009-01-01

    threats and personal stress. So far, the evidence-based findings on human resource development (HRD) seem not to match these huge challenges. The aim of this study is to identify cost-effective means of mental training to recover sufficiently from the present bias to enable more sustainable decisions...... making as required to meet the global challenges in study as confirmed by an intercultural neuroeconomic comparative study between Asian and Western cultures. However, a cultural barrier in the Western cultural tradition against meditative introversion has to be overcome to improve the time horizon...... meditation, Harvard relaxation procedure, ACEM meditation and Autogenic training. IV. Broad health effects of regular medical meditation are evidenced by RCT and even reviews/meta-analysis in more medical meditation settings: Recovery from basal anxiety Stabilization of plasma cortisol Independence...

  1. Static potential in a string model with extrinsic curvatures

    International Nuclear Information System (INIS)

    Olesen, P.; Yang, S.K.

    1987-01-01

    The static quark potential in a string model including extrinsix curvature effects is studied in the large d limit, where d is the dimensionality of euclidean space. At large distances it is explicitly shown that the physical string tension is dynamically generated. Examining the large-distance ''Coulomb'' term in the potential, we show that the non-perturbative effects in general generate non-gaussian efective theories in the infrared regime. At large distances the d → ∞ saddle point is stable for a large range of parameters. (orig.)

  2. Raising trophy kids: The role of mothers' contingent self-esteem in maternal promotion of extrinsic goals.

    Science.gov (United States)

    Soenens, Bart; Wuyts, Dorien; Vansteenkiste, Maarten; Mageau, Geneviève A; Brenning, Katrijn

    2015-07-01

    This study examined the role of mothers' child-invested contingent self-esteem, that is, their tendency to hinge their self-worth on their child's achievements, in maternal promotion of extrinsic goals, as perceived by adolescents. It was also examined whether maternal promotion of extrinsic goals would, in turn, relate to adolescents' Social Dominance Orientation (SDO). Participants were 184 mothers and their adolescent children (66% female). Maternal child-invested contingent self-esteem predicted adolescent-perceived maternal promotion of extrinsic goals, even when taking into account the variance shared between the promotion of extrinsic goals and mothers' use of a controlling parenting style. Maternal child-invested contingent self-esteem also moderated associations between mothers' personal pursuit of extrinsic goals and their promotion of those goals, such that the association between mothers' own extrinsic goals and their promotion of those goals was significant only among mothers high on child-invested contingent self-esteem. Maternal promotion of extrinsic goals was, in turn, related to adolescent SDO, suggesting that the dynamics examined in this study ultimately relate to adolescents' social and ideological development. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  3. Generational differences in American students' reasons for going to college, 1971-2014: The rise of extrinsic motives.

    Science.gov (United States)

    Twenge, Jean M; Donnelly, Kristin

    2016-01-01

    We examined generational differences in reasons for attending college among a nationally representative sample of college students (N = 8 million) entering college between 1971-2014. We validated the items on reasons for attending college against an established measure of extrinsic and intrinsic values among college students in 2014 (n = 189). Millennials (in college 2000s-2010s) and Generation X (1980s-1990s) valued extrinsic reasons for going to college ("to make more money") more, and anti-extrinsic reasons ("to gain a general education and appreciation of ideas") less than Boomers when they were the same age in the 1960s-1970s. Extrinsic reasons for going to college were higher in years with more income inequality, college enrollment, and extrinsic values. These results mirror previous research finding generational increases in extrinsic values begun by GenX and continued by Millennials, suggesting that more recent generations are more likely to favor extrinsic values in their decision-making.

  4. <strong>Neuroeconomics and Health Economicsstrong>/>

    DEFF Research Database (Denmark)

    Larsen, Torben

    2009-01-01

    activation of Amygdala - a key center in our emotional arousal (limbic system) - as shaped in the elder stone-age with many acute threats. II. In general, the Hawthorne-effect of management is explained as the result of supportive job-relations reinforcing the homeostatic properties of the limbic system...... with de-stressing benefits as reduced anxiety, less use of stimulants and a reduction of blood pressure which in all increase life-expectancy. Conclusion: Neuroeconomics helps economists to identify dominant health economic interventions that may be overlooked by traditional discipålines   [i] This part...

  5. SOLVENT EFFECTS ON THE HYDRATION OF CYCLOHEXENE CATALYZED BY A STRONG ACID ION-EXCHANGE RESIN .3. EFFECT OF SULFOLANE ON THE EQUILIBRIUM CONVERSION

    NARCIS (Netherlands)

    PANNEMAN, HJ; BEENACKERS, AACM

    The liquid-phase hydration of cyclohexene, a pseudo-first-order reversible reaction catalyzed by a strong acid ion-exchange resin, was investigated in solvent mixtures of water and sulfolane. Macroporous Amberlite XE 307 was used because of its superior catalytic activity. Chemical equilibrium

  6. <strong>Neuroeconomics and behavioral health economicsstrong>/>

    DEFF Research Database (Denmark)

    Larsen, Torben

    2009-01-01

    dissemination of relaxation procedures is evident in industrialized countries since about 1970 both inside the medical healthcare system and as NGO-settings in a market-alike competition. However, a serious barrier to the dissemination of meditative de-stressing is the lack of general knowledge of the action...... for explanation of the neural dynamics of normal decision making. Secondly, the literature is reviewed for evidence on hypothesized applications of NeM in behavioral health. Results I. The present bias as documented by neuroeconomic game-trials is explained by NeM as rooted in the basal activation of Amygdala...... - a key center in our emotional arousal (limbic system) - as shaped in the elder stone-age with many acute threats. II. In general, the Hawthorne-effect of human-relations management is explained as the result of supportive job-relations relaxing Amygdala for better emotional integration...

  7. <strong>Neuroeconomics and behavioral health economicsstrong>/>

    DEFF Research Database (Denmark)

    Larsen, Torben

    2009-01-01

    - a key center in our emotional arousal (limbic system) - as shaped in the elder stone-age with many acute threats. II. In general, the Hawthorne-effect of human-relations management is explained as the result of supportive job-relations relaxing Amygdala for better emotional integration...... some are rooted in the religious tradition while other aim to be post-religious. Medical meditation across settings combines savings on health care costs with de-stressing benefits as reduced anxiety, less use of stimulants and a reduction of blood pressure which in all increase life...... is met by a meso-strategy aiming the formation of an international, multidisciplinary network which might organize regional workshops for representatives for all involved parties in order to prepare local implementation projects.   Regarding de-stressing by medical meditation a relatively fast...

  8. Effects of strong CYP2D6 and 3A4 inhibitors, paroxetine and ketoconazole, on the pharmacokinetics and cardiovascular safety of tamsulosin

    Science.gov (United States)

    Troost, Joachim; Tatami, Shinji; Tsuda, Yasuhiro; Mattheus, Michaela; Mehlburger, Ludwig; Wein, Martina; Michel, Martin C

    2011-01-01

    AIM To determine the effect of the strong CYP2D6 inhibitor paroxetine and strong CYP3A4 inhibitor ketoconazole on the pharmacokinetics and safety (orthostatic challenge) of tamsulosin. METHODS Two open-label, randomized, two-way crossover studies were conducted in healthy male volunteers (extensive CYP2D6 metabolizers). RESULTS Co-administration of multiple oral doses of 20 mg paroxetine once daily with a single oral dose of the 0.4 mg tamsulosin HCl capsule increased the adjusted geometric mean (gMean) values of Cmax and AUC(0,∞) of tamsulosin by factors of 1.34 (90% CI 1.21, 1.49) and 1.64 (90% CI 1.44, 1.85), respectively, and increased the terminal half-life (t1/2) of tamsulosin HCl from 11.4 h to 15.3 h. Co-administration of multiple oral doses of 400 mg ketoconazole once dailywith a single oral dose of the 0.4 mg tamsulosin increased the gMean values of Cmax and AUC(0,∞) of tamsulosin by a factor of 2.20 (90% CI 1.96, 2.45) and 2.80 (90% CI 2.56, 3.07), respectively. The terminal half-life was slightly increased from 10.5 h to 11.8 h. These pharmacokinetic changes were not accompanied by clinically significant alterations of haemodynamic responses during orthostatic stress testing. CONCLUSION The exposure to tamsulosin is increased upon co-administration of strong CYP2D6 inhibitors and even more so of strong 3A4 inhibitors, but neither PK alteration was accompanied by clinically significant haemodynamic changes during orthostatic stress testing. PMID:21496064

  9. PARP Inhibition Restores Extrinsic Apoptotic Sensitivity in Glioblastoma

    Science.gov (United States)

    Karpel-Massler, Georg; Pareja, Fresia; Aimé, Pascaline; Shu, Chang; Chau, Lily; Westhoff, Mike-Andrew; Halatsch, Marc-Eric; Crary, John F.; Canoll, Peter; Siegelin, Markus D.

    2014-01-01

    Background Resistance to apoptosis is a paramount issue in the treatment of Glioblastoma (GBM). We show that targeting PARP by the small molecule inhibitors, Olaparib (AZD-2281) or PJ34, reduces proliferation and lowers the apoptotic threshold of GBM cells in vitro and in vivo. Methods The sensitizing effects of PARP inhibition on TRAIL-mediated apoptosis and potential toxicity were analyzed using viability assays and flow cytometry in established GBM cell lines, low-passage neurospheres and astrocytes in vitro. Molecular analyses included western blots and gene silencing. In vivo, effects on tumor growth were examined in a murine subcutaneous xenograft model. Results The combination treatment of PARP inhibitors and TRAIL led to an increased cell death with activation of caspases and inhibition of formation of neurospheres when compared to single-agent treatment. Mechanistically, pharmacological PARP inhibition elicited a nuclear stress response with up-regulation of down-stream DNA-stress response proteins, e.g., CCAAT enhancer binding protein (C/EBP) homology protein (CHOP). Furthermore, Olaparib and PJ34 increased protein levels of DR5 in a concentration and time-dependent manner. In turn, siRNA-mediated suppression of DR5 mitigated the effects of TRAIL/PARP inhibitor-mediated apoptosis. In addition, suppression of PARP-1 levels enhanced TRAIL-mediated apoptosis in malignant glioma cells. Treatment of human astrocytes with the combination of TRAIL/PARP inhibitors did not cause toxicity. Finally, the combination treatment of TRAIL and PJ34 significantly reduced tumor growth in vivo when compared to treatment with each agent alone. Conclusions PARP inhibition represents a promising avenue to overcome apoptotic resistance in GBM. PMID:25531448

  10. "Coveting thy neighbour's legs": a qualitative study of exercisers' experiences of intrinsic and extrinsic goal pursuit.

    Science.gov (United States)

    Sebire, Simon J; Standage, Martyn; Gillison, Fiona B; Vansteenkiste, Maarten

    2013-06-01

    Goals are central to exercise motivation, although not all goals (e.g., health vs. appearance goals) are equally psychologically or behaviorally adaptive. Within goal content theory (Vansteenkiste, Niemiec, & Soenens, 2010), goals are adaptive to the extent to which they satisfy psychological needs for autonomy, competence, and relatedness. However, little is known about what exercisers pursuing different goals are feeling, doing, thinking, and paying attention to that may help to explain the association between goal contents and need satisfaction. Using semistructured interviews and interpretative phenomenological analysis, we explored experiences of exercise among 11 adult exercisers who reported pursuing either predominantly intrinsic or extrinsic goals. Four themes emerged: (a) observation of others and resulting emotions, (b) goal expectations and time perspective, (c) markers of progress and (d) reactions to (lack of) goal achievement. Intrinsic and extrinsic goal pursuers reported divergent experiences within these four domains. The findings illuminate potential mechanisms by which different goals may influence psychological and behavioral outcomes in the exercise context.

  11. Bioavailability of iron to rats from processed soybean fractions determined by intrinsic and extrinsic labeling techniques

    International Nuclear Information System (INIS)

    Weaver, C.M.; Nelson, N.; Elliott, J.G.

    1984-01-01

    Intrinsic and extrinsic labeling techniques were used to measure iron bioavailability from soybean fractions (isolated soy protein, defatted flour, soy hulls, insoluble material and whey) by iron-depleted and non-iron-depleted rats. As expected, absorption of iron was higher in the iron-depleted than in the non-iron-depleted rats. In the iron-depleted group, significantly more iron was absorbed from soy whey than from other fractions. No other significant difference in iron absorption associated with iron source was observed. The higher absorption rate of iron from whey by the iron-depleted rats probably was related to a lower quantity of food consumed during the test meal by this group. Intrinsic and extrinsic labeling techniques produced similar assessments of bioavailability of iron

  12. Analysis of extrinsic and intrinsic factors that predispose elderly individuals to fall.

    Science.gov (United States)

    Almeida, Sionara Tamanini de; Soldera, Cristina Loureiro Chaves; Carli, Geraldo Attilio de; Gomes, Irênio; Resende, Thais de Lima

    2012-01-01

    In a sample of elderly individuals from Porto Alegre - RS, Brazil, to analyze the intrinsic and extrinsic factors that predispose them to the risk of falls and fractures. The study included a random sample of 267 elderly individuals, to whom two balance tests were applied: the Functional Reach Test (FRT) and the Timed Up and Go Test (TUG). The elderly also answered a questionnaire (13 questions divided into four categories) on sociodemographic and health factors. Elderly individuals from both genders (76.8% women), aged between 60 and 90 years (mean = 70.22 years, SD = ± 7.30 years) participated in the study. A statistically significant association (p factors that predispose to the risk of falls and fractures are older age, poor self-perception of eyesight, and poor selfrated health; the extrinsic factors are type of dwelling (living in a house) and a monthly income < one minimum wage.

  13. Intrinsic motivation, extrinsic motivation, and learning English as a foreign language.

    Science.gov (United States)

    Shaikholeslami, Razieh; Khayyer, Mohammad

    2006-12-01

    The objective of this study was to examine the relationships of amotivation, extrinsic motivation, and intrinsic motivation with learning the English language. The 230 Iranian students at Shiraz University were tested using the Language Learning Orientations Scales to measure Amotivation, Extrinsic Motivation, and Intrinsic Motivation as explanatory variables. Grade point average in English exams was selected as a measure of English learning Achievement. Multiple regression analysis revealed that learning Achievement scores were predicted by scores on the Amotivation subscale, Introjected Regulation subscale, Knowledge subscale, and Stimulation subscale, whereas, the External and Identified Regulation and Accomplishment subscales did not have a significant relationship with Achievement. The results are discussed in terms of differences in Iranian context and culture.

  14. Estimating consumer preferences for extrinsic and intrinsic attributes of vegetables. A study of German consumers

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez-Guerrero, J. F.; Gazquez-Abad, J. C.; Huertas-Garcia, R.; Mondejar-Jimenez, J. A.

    2012-11-01

    Preference formation developed during the consumers evaluation of alternatives is one of the most important stages in models of consumer purchasing behaviour. This is especially true for the purchase of vegetables. The purpose of this paper is to analyze the role of extrinsic versus intrinsic attributes in the behaviour of consumer when purchasing cucumbers, considering four attributes; price, country of origin and production method (extrinsic), and freshness (intrinsic). Utilizing a sample of German tourists visiting the city of Almeria (Spain), conjoint analysis methodology is used. The results suggest that an intrinsic aspect (freshness) is the most important attribute for consumers. Therefore, marketers are advised to consider the importance of this attribute to the consumer and try to position the product in the destination markets on the basis of product freshness. (Author) 91 refs.

  15. Integrating species traits with extrinsic threats: closing the gap between predicting and preventing species declines

    Science.gov (United States)

    Murray, Kris A.; Rosauer, Dan; McCallum, Hamish; Skerratt, Lee F.

    2011-01-01

    In studies of extinction risk, it is often insufficient to conclude that species with narrow ranges or small clutch sizes require prioritized protection. To improve conservation outcomes, we also need to know which threats interact with these traits to endanger some species but not others. In this study, we integrated the spatial patterns of key threats to Australian amphibians with species' ecological/life-history traits to both predict declining species and identify their likely threats. In addition to confirming the importance of previously identified traits (e.g. narrow range size), we find that extrinsic threats (primarily the disease chytridiomycosis and invasive mosquitofish) are equally important and interact with intrinsic traits (primarily ecological group) to create guild-specific pathways to decline in our model system. Integrating the spatial patterns of extrinsic threats in extinction risk analyses will improve our ability to detect and manage endangered species in the future, particularly where data deficiency is a problem. PMID:20980304

  16. Multiple-geographic-scale genetic structure of two mangrove tree species: the roles of mating system, hybridization, limited dispersal and extrinsic factors.

    Directory of Open Access Journals (Sweden)

    Gustavo M Mori

    Full Text Available Mangrove plants comprise a unique group of organisms that grow within the intertidal zones of tropical and subtropical regions and whose distributions are influenced by both biotic and abiotic factors. To understand how these extrinsic and intrinsic processes influence a more fundamental level of the biological hierarchy of mangroves, we studied the genetic diversity of two Neotropical mangrove trees, Avicenniagerminans and A. schaueriana, using microsatellites markers. As reported for other sea-dispersed species, there was a strong differentiation between A. germinans and A. schaueriana populations sampled north and south of the northeastern extremity of South America, likely due to the influence of marine superficial currents. Moreover, we observed fine-scale genetic structures even when no obvious physical barriers were present, indicating pollen and propagule dispersal limitation, which could be explained by isolation-by-distance coupled with mating system differences. We report the first evidence of ongoing hybridization between Avicennia species and that these hybrids are fertile, although this interspecific crossing has not contributed to an increase in the genetic diversity the populations where A. germinans and A. schaueriana hybridize. These findings highlight the complex interplay between intrinsic and extrinsic factors that shape the distribution of the genetic diversity in these sea-dispersed colonizer species.

  17. Multiple-Geographic-Scale Genetic Structure of Two Mangrove Tree Species: The Roles of Mating System, Hybridization, Limited Dispersal and Extrinsic Factors

    Science.gov (United States)

    Mori, Gustavo M.; Zucchi, Maria I.; Souza, Anete P.

    2015-01-01

    Mangrove plants comprise a unique group of organisms that grow within the intertidal zones of tropical and subtropical regions and whose distributions are influenced by both biotic and abiotic factors. To understand how these extrinsic and intrinsic processes influence a more fundamental level of the biological hierarchy of mangroves, we studied the genetic diversity of two Neotropical mangrove trees, Avicenniagerminans and A. schaueriana, using microsatellites markers. As reported for other sea-dispersed species, there was a strong differentiation between A. germinans and A. schaueriana populations sampled north and south of the northeastern extremity of South America, likely due to the influence of marine superficial currents. Moreover, we observed fine-scale genetic structures even when no obvious physical barriers were present, indicating pollen and propagule dispersal limitation, which could be explained by isolation-by-distance coupled with mating system differences. We report the first evidence of ongoing hybridization between Avicennia species and that these hybrids are fertile, although this interspecific crossing has not contributed to an increase in the genetic diversity the populations where A. germinans and A. schaueriana hybridize. These findings highlight the complex interplay between intrinsic and extrinsic factors that shape the distribution of the genetic diversity in these sea-dispersed colonizer species. PMID:25723532

  18. A Randomized Controlled Clinical Trial to Evaluate Extrinsic Stain Removal of a Whitening Dentifrice.

    Science.gov (United States)

    Terézhalmy, Géza; He, Tao; Anastasia, Mary Kay; Eusebio, Rachelle

    2016-12-01

    To evaluate the extrinsic stain removal efficacy of a new whitening dentifrice containing sodium hexametaphosphate (SHMP) over a two-week period. This study used a controlled and randomized, examiner-blind, single-center, two-treatment, parallel group design. Subjects with visible extrinsic dental stain on facial surfaces of their anterior teeth, and meeting all study criteria, were entered into the trial. The test group received the whitening dentifrice with sodium fluoride and SHMP and an ADA reference soft manual toothbrush. Subjects in the control group received a dental prophylaxis after the initial examination at Baseline and were instructed to use their usual oral hygiene products at home. Subjects returned at Day 3 and Week 2 for re-evaluation of extrinsic dental stain. Extrinsic stain was measured using the Interproximal Modified Lobene (IML) Stain Index; safety was assessed based on clinical examination. Fifty subjects (mean age 32.0 years) completed the study, with 25 in each group. Statistically significant reductions in composite stain for whole tooth, as well as interproximal, gingival, and body surfaces were observed for both groups at Day 3 and Week 2 (p 0.3). At Day 3, median percent reductions in composite IML stain from Baseline were 98% for the prophylaxis group and 100% for the test dentifrice group. At Week 2, median percent reductions in composite IML stain were 100% compared to Baseline for both groups. No adverse events were reported for either group. The whitening dentifrice demonstrated a statistically significant reduction in IML stain after three days and two weeks of use relative to baseline. Stain reduction with the toothpaste was comparable to a dental prophylaxis.

  19. Iron absorption studies from Philippine meals using isotope techniques. 1. Double isotope extrinsic tag method

    International Nuclear Information System (INIS)

    Marzan, A.M.; Morck, T.A.; Cook, J.D.

    1980-01-01

    Two different complete test meals extrinsically tagged with Fe-55 and Fe-59 together with a reference dose of iron were administered to 17 normal American volunteers. Serial iron absorption was determined from the whole blood levels of individual subjects as well as to the nutrient composition of the test meal. The results of the study indicate the presence of an optimum proportion of nutrients favouring high iron absorption. (author)

  20. When are Rewards Bad for Creativity? Examining the Role of Leadership and Integrated Extrinsic Motivation

    OpenAIRE

    Gupta, Vishal

    2014-01-01

    The relationship between common creativity antecedents and creative performance is seldom clarified and the assertion that employee attitudinal and work environment factors spur creative performance has rarely been tested. The present study adopts an individual level of analysis and investigates the association between leader behaviors, employee extrinsic motivation, creative performance behaviors and creative performance in the Indian R&D context. Data were collected using a survey questionn...