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Sample records for pupil size affects

  1. Luminance controlled pupil size affects Landolt C task performance. Revision

    Energy Technology Data Exchange (ETDEWEB)

    Berman, S.M. [Lawrence Berkeley Lab., CA (United States); Fein, G. [Neurobehavioral Lab. Software, San Rafael, CA (United States); Jewett, D.L.; Ashford, F. [ABRATech Corp., Mill Valley, CA (United States)

    1993-02-01

    Subjects judged the orientation of a 2 min. gap Landolt C located at a distance of 2.4 m. The stimuli were presented in central vision on a CRT, at low to medium contrast. The effects of varying the spectrum and luminance of surround lighting were assessed on both pupil size (measured using infrared pupillometry during task performance) and task accuracy. The task display was protected from the surround lighting, so that its luminance and contrast could be varied independently of the changes in the surround lighting. Indirect surround illumination was provided by either two illuminants of very different scotopic spectral content but with the same photopic luminance (Experiments 1 and 3), or by using the same illuminant at two different luminance levels (Experiment 2). In Experiment 3, the effect of changing surround spectrum was compared to the effect of varying task background luminance between 12 cd/m{sup 2} and 73 cd/m{sup 2}. In all experiments, scotopically enhanced surround lighting produced pupil areas which were reduced by almost 50% in comparison with surround lighting with relatively less scotopic luminance. Concomitantly there was improvement in Landolt C task performance with the scotopically enhanced surround lighting at all contrast and luminance levels. In these experiments, smaller pupil sizes were associated with significantly better visual-task performance in spite of lower task retinal illuminance when compared to the condition with larger pupils. These results suggest that changes in surround spectrum can compensate for the effect on task performance of a reduction in task luminance and supports the hypothesis that lighting energy savings could accrue in the workplace by shifting lamp spectra to obtain greater scotopic efficacy.

  2. Luminance controlled pupil size affects Landolt C task performance

    Energy Technology Data Exchange (ETDEWEB)

    Berman, S.M. (Lawrence Berkeley Lab., CA (United States)); Fein, G. (Neurobehavioral Lab. Software, San Rafael, CA (United States)); Jewett, D.L.; Ashford, F. (ABRATech Corp., Mill Valley, CA (United States))

    1993-02-01

    Subjects judged the orientation of a 2 min. gap Landolt C located at a distance of 2.4 m. The stimuli were presented in central vision on a CRT, at low to medium contrast. The effects of varying the spectrum and luminance of surround lighting were assessed on both pupil size (measured using infrared pupillometry during task performance) and task accuracy. The task display was protected from the surround lighting, so that its luminance and contrast could be varied independently of the changes in the surround lighting. Indirect surround illumination was provided by either two illuminants of very different scotopic spectral content but with the same photopic luminance (Experiments 1 and 3), or by using the same illuminant at two different luminance levels (Experiment 2). In Experiment 3, the effect of changing surround spectrum was compared to the effect of varying task background luminance between 12 cd/m[sup 2] and 73 cd/m[sup 2]. In all experiments, scotopically enhanced surround lighting produced pupil areas which were reduced by almost 50% in comparison with surround lighting with relatively less scotopic luminance. Concomitantly there was improvement in Landolt C task performance with the scotopically enhanced surround lighting at all contrast and luminance levels. In these experiments, smaller pupil sizes were associated with significantly better visual-task performance in spite of lower task retinal illuminance when compared to the condition with larger pupils. These results suggest that changes in surround spectrum can compensate for the effect on task performance of a reduction in task luminance and supports the hypothesis that lighting energy savings could accrue in the workplace by shifting lamp spectra to obtain greater scotopic efficacy.

  3. Pupil size influences the eye-tracker signal during saccades.

    Science.gov (United States)

    Nyström, Marcus; Hooge, Ignace; Andersson, Richard

    2016-04-01

    While it is known that scleral search coils-measuring the rotation of the eye globe--and modern, video based eye trackers-tracking the center of the pupil and the corneal reflection (CR)--produce signals with different properties, the mechanisms behind the differences are less investigated. We measure how the size of the pupil affects the eye-tracker signal recorded during saccades with a common pupil-CR eye-tracker. Eye movements were collected from four healthy participants and one person with an aphakic eye while performing self-paced, horizontal saccades at different levels of screen luminance and hence pupil size. Results show that pupil-, and gaze-signals, but not the CR-signal, are affected by the size of the pupil; changes in saccade peak velocities in the gaze signal of more than 30% were found. It is important to be aware of this pupil size dependent change when comparing fine grained oculomotor behavior across participants and conditions.

  4. Pupil size tracks perceptual content and surprise.

    Science.gov (United States)

    Kloosterman, Niels A; Meindertsma, Thomas; van Loon, Anouk M; Lamme, Victor A F; Bonneh, Yoram S; Donner, Tobias H

    2015-04-01

    Changes in pupil size at constant light levels reflect the activity of neuromodulatory brainstem centers that control global brain state. These endogenously driven pupil dynamics can be synchronized with cognitive acts. For example, the pupil dilates during the spontaneous switches of perception of a constant sensory input in bistable perceptual illusions. It is unknown whether this pupil dilation only indicates the occurrence of perceptual switches, or also their content. Here, we measured pupil diameter in human subjects reporting the subjective disappearance and re-appearance of a physically constant visual target surrounded by a moving pattern ('motion-induced blindness' illusion). We show that the pupil dilates during the perceptual switches in the illusion and a stimulus-evoked 'replay' of that illusion. Critically, the switch-related pupil dilation encodes perceptual content, with larger amplitude for disappearance than re-appearance. This difference in pupil response amplitude enables prediction of the type of report (disappearance vs. re-appearance) on individual switches (receiver-operating characteristic: 61%). The amplitude difference is independent of the relative durations of target-visible and target-invisible intervals and subjects' overt behavioral report of the perceptual switches. Further, we show that pupil dilation during the replay also scales with the level of surprise about the timing of switches, but there is no evidence for an interaction between the effects of surprise and perceptual content on the pupil response. Taken together, our results suggest that pupil-linked brain systems track both the content of, and surprise about, perceptual events.

  5. Pupil size reflects the focus of feature-based attention.

    Science.gov (United States)

    Binda, Paola; Pereverzeva, Maria; Murray, Scott O

    2014-12-15

    We measured pupil size in adult human subjects while they selectively attended to one of two surfaces, bright and dark, defined by coherently moving dots. The two surfaces were presented at the same location; therefore, subjects could select the cued surface only on the basis of its features. With no luminance change in the stimulus, we find that pupil size was smaller when the bright surface was attended and larger when the dark surface was attended: an effect of feature-based (or surface-based) attention. With the same surfaces at nonoverlapping locations, we find a similar effect of spatial attention. The pupil size modulation cannot be accounted for by differences in eye position and by other variables known to affect pupil size such as task difficulty, accommodation, or the mere anticipation (imagery) of bright/dark stimuli. We conclude that pupil size reflects not just luminance or cognitive state, but the interaction between the two: it reflects which luminance level in the visual scene is relevant for the task at hand.

  6. Pupil size behavior during online processing of sentences.

    Science.gov (United States)

    Fernández, G; Biondi, J; Castro, S; Agamenonni, O

    2016-12-01

    In the present work we analyzed the pupil size behavior of 40 subjects while they read well-defined sentences with different contextual predictability (i.e., regular sentences and proverbs). In general, pupil size increased when reading regular sentences, but when readers realized that they were reading proverbs their pupils strongly increase until finishing proverbs' reading. Our results suggest that an increased pupil size is not limited to cognitive load (i.e., relative difficulty in processing) because when participants accurately recognized words during reading proverbs, theirs pupil size increased too. Our results show that pupil size dynamics may be a reliable measure to investigate the cognitive processes involved in sentence processing and memory functioning.

  7. A circuit for pupil orienting responses: implications for cognitive modulation of pupil size.

    Science.gov (United States)

    Wang, Chin-An; Munoz, Douglas P

    2015-08-01

    Pupil size, as a component of orienting, changes rapidly in response to local salient events in the environment, in addition to its well-known illumination-dependent modulation. Recent research has shown that visual, auditory, or audiovisual stimuli can elicit transient pupil dilation, and the timing and size of the evoked responses are systematically modulated by stimulus salience. Moreover, weak microstimulation of the superior colliculus (SC), a midbrain structure involved in eye movements and attention, evokes similar transient pupil dilation, suggesting that the SC coordinates the orienting response which includes transient pupil dilation. Projections from the SC to the pupil control circuitry provide a novel neural substrate underlying pupil modulation by various cognitive processes.

  8. Computerized mouse pupil size measurement for pupillary light reflex analysis.

    Science.gov (United States)

    Lu, Wei; Tan, Jinglu; Zhang, Keqing; Lei, Bo

    2008-06-01

    Accurate measurement of pupil size is essential for pupillary light reflex (PLR) analysis in clinical diagnosis and vision research. Low pupil-iris contrast, corneal reflection, artifacts and noises in infrared eye imaging pose challenges for automated pupil detection and measurement. This paper describes a computerized method for pupil detection or identification. After segmentation by a region-growing algorithm, pupils are detected by an iterative randomized Hough transform (IRHT) with an elliptical model. The IRHT iteratively suppresses the effects of extraneous structures and noise, yielding reliable measurements. Experimental results with 72 images showed a mean absolute difference of 3.84% between computerized and manual measurements. The inter-run variation for the computerized method (1.24%) was much smaller than the inter-observer variation for the manual method (7.45%), suggesting a higher level of consistency of the former. The computerized method could facilitate PLR analysis and other non-invasive functional tests that require pupil size measurements.

  9. Pupil size directly modulates the feedforward response in human primary visual cortex independently of attention.

    Science.gov (United States)

    Bombeke, Klaas; Duthoo, Wout; Mueller, Sven C; Hopf, Jens-Max; Boehler, C Nico

    2016-02-15

    Controversy revolves around the question of whether psychological factors like attention and emotion can influence the initial feedforward response in primary visual cortex (V1). Although traditionally, the electrophysiological correlate of this response in humans (the C1 component) has been found to be unaltered by psychological influences, a number of recent studies have described attentional and emotional modulations. Yet, research into psychological effects on the feedforward V1 response has neglected possible direct contributions of concomitant pupil-size modulations, which are known to also occur under various conditions of attentional load and emotional state. Here we tested the hypothesis that such pupil-size differences themselves directly affect the feedforward V1 response. We report data from two complementary experiments, in which we used procedures that modulate pupil size without differences in attentional load or emotion while simultaneously recording pupil-size and EEG data. Our results confirm that pupil size indeed directly influences the feedforward V1 response, showing an inverse relationship between pupil size and early V1 activity. While it is unclear in how far this effect represents a functionally-relevant adaptation, it identifies pupil-size differences as an important modulating factor of the feedforward response of V1 and could hence represent a confounding variable in research investigating the neural influence of psychological factors on early visual processing.

  10. Chimpanzees and humans mimic pupil-size of conspecifics.

    Science.gov (United States)

    Kret, Mariska E; Tomonaga, Masaki; Matsuzawa, Tetsuro

    2014-01-01

    Group-living typically provides benefits to individual group members but also confers costs. To avoid incredulity and betrayal and allow trust and cooperation, individuals must understand the intentions and emotions of their group members. Humans attend to other's eyes and from gaze and pupil-size cues, infer information about the state of mind of the observed. In humans, pupil-size tends to mimic that of the observed. Here we tested whether pupil-mimicry exists in our closest relative, the chimpanzee (P. troglodytes). We conjectured that if pupil-mimicry has adaptive value, e.g. to promote swift communication of inner states and facilitate shared understanding and coordination, pupil-mimicry should emerge within but not across species. Pupillometry data was collected from human and chimpanzee subjects while they observed images of the eyes of both species with dilating/constricting pupils. Both species showed enhanced pupil-mimicry with members of their own species, with effects being strongest in humans and chimpanzee mothers. Pupil-mimicry may be deeply-rooted, but probably gained importance from the point in human evolution where the morphology of our eyes became more prominent. Humans' white sclera surrounding the iris, and the fine muscles around their eyes facilitate non-verbal communication via eye signals.

  11. Chimpanzees and humans mimic pupil-size of conspecifics.

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    Mariska E Kret

    Full Text Available Group-living typically provides benefits to individual group members but also confers costs. To avoid incredulity and betrayal and allow trust and cooperation, individuals must understand the intentions and emotions of their group members. Humans attend to other's eyes and from gaze and pupil-size cues, infer information about the state of mind of the observed. In humans, pupil-size tends to mimic that of the observed. Here we tested whether pupil-mimicry exists in our closest relative, the chimpanzee (P. troglodytes. We conjectured that if pupil-mimicry has adaptive value, e.g. to promote swift communication of inner states and facilitate shared understanding and coordination, pupil-mimicry should emerge within but not across species. Pupillometry data was collected from human and chimpanzee subjects while they observed images of the eyes of both species with dilating/constricting pupils. Both species showed enhanced pupil-mimicry with members of their own species, with effects being strongest in humans and chimpanzee mothers. Pupil-mimicry may be deeply-rooted, but probably gained importance from the point in human evolution where the morphology of our eyes became more prominent. Humans' white sclera surrounding the iris, and the fine muscles around their eyes facilitate non-verbal communication via eye signals.

  12. Eye movement and pupil size constriction under discomfort glare.

    Science.gov (United States)

    Lin, Yandan; Fotios, Steve; Wei, Minchen; Liu, Yihong; Guo, Weihong; Sun, Yaojie

    2015-01-29

    Involuntary physiological responses offer an alternative means to psychophysical procedures for objectively evaluating discomfort glare. This study examined eye movement and pupil size responses to glare discomfort using new approaches to analysis: relative pupil size and speed of eye movement. Participants evaluated glare discomfort using the standard de Boer rating scale under various conditions manipulated to influence glare discomfort. Eye movement was recorded using an electro-oculogram (EOG), and pupil size was recorded using Tobii glasses. Ten young (mean age: 24.5 years old) and 10 senior (mean age: 61 years old) participants were recruited for this experiment. Subjective evaluation of glare discomfort was highly correlated with eye movement (multiple correlation coefficient [R(2)] of >0.94, P < 0.001) and pupil constriction (R(2) = 0.38, P < 0.001). Severe glare discomfort increased the speed of eye movement and caused larger pupil constriction. Larger variations of eye movement were found among seniors. The two physiological responses studied here to characterize discomfort glare under various lighting conditions had significant correlation with the subjective evaluation. The correlation between discomfort glare and physiological responses suggests an objective way to characterize and evaluate discomfort glare that may overcome the problems of conventional subjective evaluation. It also offers an explanation as to why long-term exposure to discomfort glare leads to visual fatigue and eyestrain. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  13. Effect of pupil size on multifocal pattern visual evoked potentials.

    Science.gov (United States)

    Martins, Alessandra; Balachandran, Chandra; Klistorner, Alexander I; Graham, Stuart L; Billson, Francis A

    2003-08-01

    The purpose of this study was to investigate the influence of pupil diameter on the amplitude and latency of multifocal visual evoked potentials (mfVEP). The multifocal objective perimeter (Accumap; Objectivision) was used to stimulate the visual field at 56 sites extending to 32 degrees using a pseudo-random pattern stimulus. The mfVEP were recorded using bipolar occipital electrodes, 7 min/eye. Ten normal subjects were recruited from the community and one eye was randomly selected for testing. The mfVEP were recorded at four different pupil diameters (2 mm, 4 mm, 6 mm, 8 mm), obtained by applying tropicamide (0.5%) or pilocarpine (2%) in different dilutions. Appropriate refractive correction was provided to overcome cycloplegia and achieve a visual acuity of 6/7.5 or better. Analysis revealed that at most pupil diameters the normalized full field amplitude did not show significant variation, except at the most miotic pupil diameter (2 mm), where the amplitude became reduced, based on 2-way anova and Tukey's T method. There was, however, significant correlation between latency and pupil area (correlation coefficient: upper field -0.63, lower field -0.76). The results suggest that even in the presence of mydriatics or miotics, the mfVEP test can be used to assess diseases that affect amplitude, provided near correction is used. The interpretation of latency, however, must be made with caution, as a borderline conduction defect with a dilated pupil may appear normal.

  14. Effect of Pupil Size on Wavefront Refraction during Orthokeratology.

    Science.gov (United States)

    Faria-Ribeiro, Miguel; Navarro, Rafael; González-Méijome, José Manuel

    2016-11-01

    It has been hypothesized that central and peripheral refraction, in eyes treated with myopic overnight orthokeratology, might vary with changes in pupil diameter. The aim of this work was to evaluate the axial and peripheral refraction and optical quality after orthokeratology, using ray tracing software for different pupil sizes. Zemax-EE was used to generate a series of 29 semi-customized model eyes based on the corneal topography changes from 29 patients who had undergone myopic orthokeratology. Wavefront refraction in the central 80 degrees of the visual field was calculated using three different quality metrics criteria: Paraxial curvature matching, minimum root mean square error (minRMS), and the Through Focus Visual Strehl of the Modulation Transfer Function (VSMTF), for 3- and 6-mm pupil diameters. The three metrics predicted significantly different values for foveal and peripheral refractions. Compared with the Paraxial criteria, the other two metrics predicted more myopic refractions on- and off-axis. Interestingly, the VSMTF predicts only a marginal myopic shift in the axial refraction as the pupil changes from 3 to 6 mm. For peripheral refraction, minRMS and VSMTF metric criteria predicted a higher exposure to peripheral defocus as the pupil increases from 3 to 6 mm. The results suggest that the supposed effect of myopic control produced by ortho-k treatments might be dependent on pupil size. Although the foveal refractive error does not seem to change appreciably with the increase in pupil diameter (VSMTF criteria), the high levels of positive spherical aberration will lead to a degradation of lower spatial frequencies, that is more significant under low illumination levels.

  15. Chimpanzees and humans mimic pupil-size of conspecifics

    NARCIS (Netherlands)

    Kret, M.E.; Tomonaga, M.; Matsuzawa, T.

    2014-01-01

    Group-living typically provides benefits to individual group members but also confers costs. To avoid incredulity and betrayal and allow trust and cooperation, individuals must understand the intentions and emotions of their group members. Humans attend to other's eyes and from gaze and pupil-size c

  16. Orienting of attention, pupil size, and the norepinephrine system.

    Science.gov (United States)

    Gabay, Shai; Pertzov, Yoni; Henik, Avishai

    2011-01-01

    This research examined a novel suggestion regarding the involvement of the locus coeruleus-norepinephrine (LC-NE) system in orienting reflexive (exogenous) attention. A common procedure for studying exogenous orienting of attention is Posner's cuing task. Importantly, one can manipulate the required level of target processing by changing task requirements, which, in turn, can elicit a different time course of inhibition of return (IOR). An easy task (responding to target location) produces earlier onset IOR, whereas a demanding task (responding to target identity) produces later onset IOR. Aston-Jones and Cohen (Annual Review of Neuroscience, 28, 403-450, 2005) presented a theory suggesting two different modes of LC activity: tonic and phasic. Accordingly, we suggest that in the more demanding task, the LC-NE system is activated in phasic mode, and in the easier task, it is activated in tonic mode. This, in turn, influences the appearance of IOR. We examined this suggestion by measuring participants' pupil size, which has been demonstrated to correlate with the LC-NE system, while they performed cuing tasks. We found a response-locked phasic dilation of the pupil in the discrimination task, as compared with the localization task, which may reflect different firing modes of the LC-NE system during the two tasks. We also demonstrated a correlation between pupil size at the time of cue presentation and magnitude of IOR.

  17. Effect of the observed pupil size on the amygdala of the beholders

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    Amemiya, Shiori; Ohtomo, Kuni

    2011-01-01

    Among a range of cognitive functions of the amygdala, recent studies suggest its involvement in identification of the pupil size. To further address its role, we investigated the response of the amygdala to human and cat faces with varied pupil size, taking into account the effect of the gender and subjective attractiveness ratings. Twenty-seven subjects underwent functional magnetic resonance imaging while viewing faces with large and small pupils. Large pupil faces induced increased activat...

  18. Examining the Effect of Class Size on Classroom Engagement and Teacher-Pupil Interaction: Differences in Relation to Pupil Prior Attainment and Primary vs. Secondary Schools

    Science.gov (United States)

    Blatchford, Peter; Bassett, Paul; Brown, Penelope

    2011-01-01

    It is widely recognized that we need to know more about effects of class size on classroom interactions and pupil behavior. This paper extends research by comparing effects on pupil classroom engagement and teacher-pupil interaction, and examining if effects vary by pupil attainment level and between primary and secondary schools. Systematic…

  19. Examining the Effect of Class Size on Classroom Engagement and Teacher-Pupil Interaction: Differences in Relation to Pupil Prior Attainment and Primary vs. Secondary Schools

    Science.gov (United States)

    Blatchford, Peter; Bassett, Paul; Brown, Penelope

    2011-01-01

    It is widely recognized that we need to know more about effects of class size on classroom interactions and pupil behavior. This paper extends research by comparing effects on pupil classroom engagement and teacher-pupil interaction, and examining if effects vary by pupil attainment level and between primary and secondary schools. Systematic…

  20. Can pupil size and pupil responses during visual scanning contribute to the diagnosis of autism spectrum disorder in children?

    Science.gov (United States)

    Martineau, Joëlle; Hernandez, Nadia; Hiebel, Lorraine; Roché, Laetitia; Metzger, Aude; Bonnet-Brilhault, Frédérique

    2011-08-01

    The purpose of this study was to determine whether baseline pupil size and pupil responses during visual scanning with eye-tracking technology could discriminate children with autism spectrum disorder (ASD) from mental age-matched and chronological age-matched controls. To this end, we used stimuli consisting in still color photographs presented centrally to the participant's midline on a stimulus monitor. Each child was presented with a series of neutral faces, virtual faces (avatars) and different objects, separated by black slides. We recorded the mean pupil size and pupil size changes over time in each of the three categories of stimuli and during exposure to the black slides. Fifty-seven children participated in study (19 ASD, mean age 118 months; 19 mental age-matched controls, mean age 87 months; and 19 chronological age-matched controls, mean age 118 months). We compared the baseline pupil size and pupil responses during visual scanning among the three diagnostic groups. During the presentation of slides, the mean pupil size in the ASD group was clearly smaller than in the MA-matched and CA-matched groups. Discriminate analysis of pupil size during the presentation of black slides and slides with visual stimuli successfully predicted group membership in 72% of the participants. Group membership was correctly classified in 89% of the participants in the ASD group, in 63% in the MA-matched group and in 63% in the CA-matched group. These potential biomarkers may contribute to our understanding of the differences in neurological development in the brain in autism and could prove useful as indicators of ASD.

  1. Pupil size dynamics during fixation impact the accuracy and precision of video-based gaze estimation.

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    Choe, Kyoung Whan; Blake, Randolph; Lee, Sang-Hun

    2016-01-01

    Video-based eye tracking relies on locating pupil center to measure gaze positions. Although widely used, the technique is known to generate spurious gaze position shifts up to several degrees in visual angle because pupil centration can change without eye movement during pupil constriction or dilation. Since pupil size can fluctuate markedly from moment to moment, reflecting arousal state and cognitive processing during human behavioral and neuroimaging experiments, the pupil size artifact is prevalent and thus weakens the quality of the video-based eye tracking measurements reliant on small fixational eye movements. Moreover, the artifact may lead to erroneous conclusions if the spurious signal is taken as an actual eye movement. Here, we measured pupil size and gaze position from 23 human observers performing a fixation task and examined the relationship between these two measures. Results disclosed that the pupils contracted as fixation was prolonged, at both small (pupil contractions were accompanied by systematic errors in gaze position estimation, in both the ellipse and the centroid methods of pupil tracking. When pupil size was regressed out, the accuracy and reliability of gaze position measurements were substantially improved, enabling differentiation of 0.1° difference in eye position. We confirmed the presence of systematic changes in pupil size, again at both small and large scales, and its tight relationship with gaze position estimates when observers were engaged in a demanding visual discrimination task.

  2. As Far as the Eye Can See: Relationship between Psychopathic Traits and Pupil Response to Affective Stimuli.

    Science.gov (United States)

    Burley, Daniel T; Gray, Nicola S; Snowden, Robert J

    2017-01-01

    Psychopathic individuals show a range of affective processing deficits, typically associated with the interpersonal/affective component of psychopathy. However, previous research has been inconsistent as to whether psychopathy, within both offender and community populations, is associated with deficient autonomic responses to the simple presentation of affective stimuli. Changes in pupil diameter occur in response to emotionally arousing stimuli and can be used as an objective indicator of physiological reactivity to emotion. This study used pupillometry to explore whether psychopathic traits within a community sample were associated with hypo-responsivity to the affective content of stimuli. Pupil activity was recorded for 102 adult (52 female) community participants in response to affective (both negative and positive affect) and affectively neutral stimuli, that included images of scenes, static facial expressions, dynamic facial expressions and sound-clips. Psychopathic traits were measured using the Triarchic Psychopathy Measure. Pupil diameter was larger in response to negative stimuli, but comparable pupil size was demonstrated across pleasant and neutral stimuli. A linear relationship between subjective arousal and pupil diameter was found in response to sound-clips, but was not evident in response to scenes. Contrary to predictions, psychopathy was unrelated to emotional modulation of pupil diameter across all stimuli. The findings were the same when participant gender was considered. This suggests that psychopathy within a community sample is not associated with autonomic hypo-responsivity to affective stimuli, and this effect is discussed in relation to later defensive/appetitive mobilisation deficits.

  3. As Far as the Eye Can See: Relationship between Psychopathic Traits and Pupil Response to Affective Stimuli

    Science.gov (United States)

    Gray, Nicola S.; Snowden, Robert J.

    2017-01-01

    Psychopathic individuals show a range of affective processing deficits, typically associated with the interpersonal/affective component of psychopathy. However, previous research has been inconsistent as to whether psychopathy, within both offender and community populations, is associated with deficient autonomic responses to the simple presentation of affective stimuli. Changes in pupil diameter occur in response to emotionally arousing stimuli and can be used as an objective indicator of physiological reactivity to emotion. This study used pupillometry to explore whether psychopathic traits within a community sample were associated with hypo-responsivity to the affective content of stimuli. Pupil activity was recorded for 102 adult (52 female) community participants in response to affective (both negative and positive affect) and affectively neutral stimuli, that included images of scenes, static facial expressions, dynamic facial expressions and sound-clips. Psychopathic traits were measured using the Triarchic Psychopathy Measure. Pupil diameter was larger in response to negative stimuli, but comparable pupil size was demonstrated across pleasant and neutral stimuli. A linear relationship between subjective arousal and pupil diameter was found in response to sound-clips, but was not evident in response to scenes. Contrary to predictions, psychopathy was unrelated to emotional modulation of pupil diameter across all stimuli. The findings were the same when participant gender was considered. This suggests that psychopathy within a community sample is not associated with autonomic hypo-responsivity to affective stimuli, and this effect is discussed in relation to later defensive/appetitive mobilisation deficits. PMID:28118366

  4. Disruption of pupil size modulation correlates with voluntary motor preparation deficits in Parkinson's disease.

    Science.gov (United States)

    Wang, Chin-An; McInnis, Hailey; Brien, Donald C; Pari, Giovanna; Munoz, Douglas P

    2016-01-08

    Pupil size is an easy-to-measure, non-invasive method to index various cognitive processes. Although a growing number of studies have incorporated measures of pupil size into clinical investigation, there have only been limited studies in Parkinson's disease (PD). Convergent evidence has suggested PD patients exhibit cognitive impairment at or soon after diagnosis. Here, we used an interleaved pro- and anti-saccade paradigm while monitoring pupil size with saccadic eye movements to examine the relationship between executive function deficits and pupil size in PD patients. Subjects initially fixated a central cue, the color of which instructed them to either look at a peripheral stimulus automatically (pro-saccade) or suppress the automatic response and voluntarily look in the opposite direction of the stimulus (anti-saccade). We hypothesized that deficits of voluntary control should be revealed not only on saccadic but also on pupil responses because of the recently suggested link between the saccade and pupil control circuits. In elderly controls, pupil size was modulated by task preparation, showing larger dilation prior to stimulus appearance in preparation for correct anti-saccades, compared to correct pro-saccades, or erroneous pro-saccades made in the anti-saccade condition. Moreover, the size of pupil dilation correlated negatively with anti-saccade reaction times. However, this profile of pupil size modulation was significantly blunted in PD patients, reflecting dysfunctional circuits for anti-saccade preparation. Our results demonstrate disruptions of modulated pupil responses by voluntary movement preparation in PD patients, highlighting the potential of using low-cost pupil size measurement to examine executive function deficits in early PD.

  5. Effect of the observed pupil size on the amygdala of the beholders.

    Science.gov (United States)

    Amemiya, Shiori; Ohtomo, Kuni

    2012-03-01

    Among a range of cognitive functions of the amygdala, recent studies suggest its involvement in identification of the pupil size. To further address its role, we investigated the response of the amygdala to human and cat faces with varied pupil size, taking into account the effect of the gender and subjective attractiveness ratings. Twenty-seven subjects underwent functional magnetic resonance imaging while viewing faces with large and small pupils. Large pupil faces induced increased activation in the amygdala, without interactions with either subject or stimuli gender, although no equivalent activation differences were seen for cat face stimuli. The activation differences were irrespective of the perceived attractiveness, and without explicit knowledge about the manipulation of the pupil size. These data support the idea that the amygdala is responsive not only to explicit or implicit fear, abhorrence or preference, but also to other elements that might suggest heightened vigilance of biologically relevant stimuli, which does not necessarily require subjective awareness.

  6. Pupil size signals novelty and predicts later retrieval success for declarative memories of natural scenes.

    Science.gov (United States)

    Naber, Marnix; Frässle, Stefan; Rutishauser, Ueli; Einhäuser, Wolfgang

    2013-02-08

    Declarative memories of personal experiences are a key factor in defining oneself as an individual, which becomes particularly evident when this capability is impaired. Assessing the physiological mechanisms of human declarative memory is typically restricted to patients with specific lesions and requires invasive brain access or functional imaging. We investigated whether the pupil, an accessible physiological measure, can be utilized to probe memories for complex natural visual scenes. During memory encoding, scenes that were later remembered elicited a stronger pupil constriction compared to scenes that were later forgotten. Thus, pupil size predicts success or failure of memory formation. In contrast, novel scenes elicited stronger pupil constriction than familiar scenes during retrieval. When viewing previously memorized scenes, those that were forgotten (misjudged as novel) still elicited stronger pupil constrictions than those correctly judged as familiar. Furthermore, pupil constriction was influenced more strongly if images were judged with high confidence. Thus, we propose that pupil constriction can serve as a marker of novelty. Since stimulus novelty modulates the efficacy of memory formation, our pupil measurements during learning indicate that the later forgotten images were perceived as less novel than the later remembered pictures. Taken together, our data provide evidence that pupil constriction is a physiological correlate of a neural novelty signal during formation and retrieval of declarative memories for complex, natural scenes.

  7. Pupil size influences the eye-tracker signal during saccades

    NARCIS (Netherlands)

    Nyström, M.; Hooge, I.T.C.; Anderson, R.

    2016-01-01

    While it is known that scleral search coils—measuring the rotation of the eye globe—and modern, video based eye trackers—tracking the center of the pupil and the corneal reflection (CR)—produce signals with different properties, the mechanisms behind the differences are less investigated. We measure

  8. Are Small Classes Better? Understanding Relationships between Class Size, Classroom Processes and Pupils' Learning

    Science.gov (United States)

    Pedder, David

    2006-01-01

    Twelve years ago Blatchford and Mortimore's authoritative review of class size research appeared in this journal. They concluded that a major problem with class size research was the lack of detailed studies of complex classroom processes that might mediate class size effects on pupils' learning. This article reviews two UK class size reviews and…

  9. Permanent alterations in muscarinic receptors and pupil size produced by chronic atropinization in kittens

    Energy Technology Data Exchange (ETDEWEB)

    Smith, E.L.; Redburn, D.A.; Harwerth, R.S.; Maguire, G.W.

    1984-02-01

    Chronic mydriasis was induced in six kittens (four monocular, two binocular) and two adult cats (both monocular) by the daily topical application of atropine. Both the kittens and the adult cats were atropinized for a 13-week period with the treatment regimen beginning at the time of eye opening for the kittens. Pupil size measurements, obtained 1 year after the atropinization were discontinued, revealed that, although the pupils of the adult cats were normal, the pupils of the kittens' treated eyes were consistently smaller than pupils in control eyes. The status of the muscarinic receptors in the kittens' irides was investigated using /sup 3/H-QNB binding assays. In comparison with iris muscle homogenates from the control eyes, those from the treated eyes demonstrated an eightfold increase in the number of receptor binding sites. The results indicate that pupil size can be altered permanently by chronic mydriasis initiated early in the life of a kitten and that the permanent change in pupil size may result, in part, from a type of permanent supersensitivity response in the muscle following chronic blockade of muscarinic transmission by atropine.

  10. Effect of the hypomagnetic field on the size of the eye pupil

    CERN Document Server

    Binhi, Vladimir N

    2013-01-01

    Previously, we reported that the hypomagnetic field obtained by the 100-fold deprivation of the geomagnetic field affected human cognitive processes as estimated in several computer tests. The exposure to the hypomagnetic field caused a statistically significant increase both in the task processing time and in the number of errors. The magnitude of this magnetic effect, averaged over 40 healthy subjects and more than 10^5 separate trials, was about 1.7%. In the present work, the results of a simultaneous study are described, in which the right eye of each subject was video recorded, while the subject performed the tasks. It has appeared that the pupil size grows in the hypomagnetic field. This effect has been calculated based on the treatment of a large data set of about 6.10^6 video frames. Averaged all over the frames, the magnetic effect on the pupil area was about 1.6%, with high statistical confidence. This is the first laboratory study in which the number of separate trials has been large enough to obta...

  11. Fixation duration surpasses pupil size as a measure of memory load in free viewing.

    Science.gov (United States)

    Meghanathan, Radha Nila; van Leeuwen, Cees; Nikolaev, Andrey R

    2014-01-01

    Oculomotor behavior reveals, not only the acquisition of visual information at fixation, but also the accumulation of information in memory across subsequent fixations. Two candidate measures were considered as indicators of such dynamic visual memory load: fixation duration and pupil size. While recording these measures, we displayed an arrangement of 3, 4 or 5 targets among distractors. Both occurred in various orientations. Participants searched for targets and reported whether in a subsequent display one of them had changed orientation. We determined to what extent fixation duration and pupil size indicate dynamic memory load, as a function of the number of targets fixated during the search. We found that fixation duration reflects the number of targets, both when this number is within and above the limit of working memory capacity. Pupil size reflects the number of targets only when it exceeds the capacity limit. Moreover, the duration of fixations on successive targets but not on distractors increases whereas pupil size does not. The increase in fixation duration with number of targets both within and above working memory capacity suggests that in free viewing fixation duration is sensitive to actual memory load as well as to processing load, whereas pupil size is indicative of processing load only. Two alternative models relating visual attention and working memory are considered relevant to these results. We discuss the results as supportive of a model which involves a temporary buffer in the interaction of attention and working memory.

  12. Corneal aberrations in keratoconic eyes: influence of pupil size and centering

    Energy Technology Data Exchange (ETDEWEB)

    Comastri, S A; Perez, G D; Martin, G; Bianchetti, A [Grupo de Optica y Vision, Departamento de Fisica, Facultad de Ingenieria, Universidad de Buenos Aires, P. Colon 850 (C1063ACV) Buenos Aires (Argentina); Perez, L I, E-mail: comastri@fi.uba.ar [Consejo Nacional de Investigaciones CientIficas y Tecnicas, (C1033AAJ) Buenos Aires (Argentina)

    2011-01-01

    Ocular aberrations vary among subjects and under different conditions and are commonly analyzed expanding the wavefront aberration function in Zernike polynomials. In previous articles, explicit analytical formulas to transform Zernike coefficients of up to 7th order corresponding to an original pupil into those related to a contracted displaced new pupil are obtained. In the present paper these formulas are applied to 20 keratoconic corneas of varying severity. Employing the SN CT1000 topographer, aberrations of the anterior corneal surface for a pupil of semi-diameter 3 mm centered on the keratometric axis are evaluated, the relation between the higher-order root mean square wavefront error and the index KISA% characterizing keratoconus is studied and the size and centering of the ocular photopic natural pupil are determined. Using these data and the transformation formulas, new coefficients associated to the photopic pupil size are computed and their variation when coordinates origin is shifted from the keratometric axis to the ocular pupil centre is analyzed.

  13. Pupil size reveals preparatory processes in the generation of pro-saccades and anti-saccades.

    Science.gov (United States)

    Wang, Chin-An; Brien, Donald C; Munoz, Douglas P

    2015-04-01

    The ability to generate flexible behaviors to accommodate changing goals in response to identical sensory stimuli is a signature that is inherited in humans and higher-level animals. In the oculomotor system, this function has often been examined with the anti-saccade task, in which subjects are instructed, prior to stimulus appearance, to either automatically look at the peripheral stimulus (pro-saccade) or to suppress the automatic response and voluntarily look in the opposite direction from the stimulus (anti-saccade). Distinct neural preparatory activity between the pro-saccade and anti-saccade conditions has been well documented, particularly in the superior colliculus (SC) and the frontal eye field (FEF), and this has shown higher inhibition-related fixation activity in preparation for anti-saccades than in preparation for pro-saccades. Moreover, the level of preparatory activity related to motor preparation is negatively correlated with reaction times. We hypothesised that preparatory signals may be reflected in pupil size through a link between the SC and the pupil control circuitry. Here, we examined human pupil dynamics during saccade preparation prior to the execution of pro-saccades and anti-saccades. Pupil size was larger in preparation for correct anti-saccades than in preparation for correct pro-saccades and erroneous pro-saccades made in the anti-saccade condition. Furthermore, larger pupil dilation prior to stimulus appearance accompanied saccades with faster reaction times, with a trial-by-trial correlation between dilation size and anti-saccade reaction times. Overall, our results demonstrate that pupil size is modulated by saccade preparation, and neural activity in the SC, together with the FEF, supports these findings, providing unique insights into the neural substrate coordinating cognitive processing and pupil diameter.

  14. Smaller pupil size and better proofreading performance with positive than with negative polarity displays.

    Science.gov (United States)

    Piepenbrock, Cosima; Mayr, Susanne; Buchner, Axel

    2014-01-01

    The 'positive polarity advantage' describes the fact that reading performance is better for dark text on light background (positive polarity) than for light text on dark background (negative polarity). We investigated the underlying mechanism by assessing pupil size and proofreading performance when reading positive and negative polarity texts. In particular, we tested the display luminance hypothesis which postulates that the typically greater brightness of positive compared to negative polarity displays leads to smaller pupil sizes and, hence, a sharper retinal image and better perception of detail. Indeed, pupil sizes were smaller and proofreading performance was better with positive than with negative polarity displays. The results are compatible with the hypothesis that the positive polarity advantage is an effect of display luminance. Limitations of the study are being discussed.

  15. Food aroma affects bite size

    Directory of Open Access Journals (Sweden)

    de Wijk René A

    2012-03-01

    Full Text Available Abstract Background To evaluate the effect of food aroma on bite size, a semisolid vanilla custard dessert was delivered repeatedly into the mouth of test subjects using a pump while various concentrations of cream aroma were presented retronasally to the nose. Termination of the pump, which determined bite size, was controlled by the subject via a push button. Over 30 trials with 10 subjects, the custard was presented randomly either without an aroma, or with aromas presented below or near the detection threshold. Results Results for ten subjects (four females and six males, aged between 26 and 50 years, indicated that aroma intensity affected the size of the corresponding bite as well as that of subsequent bites. Higher aroma intensities resulted in significantly smaller sizes. Conclusions These results suggest that bite size control during eating is a highly dynamic process affected by the sensations experienced during the current and previous bites.

  16. ERP-pupil size correlations reveal how bilingualism enhances cognitive flexibility.

    Science.gov (United States)

    Kuipers, Jan-Rouke; Thierry, Guillaume

    2013-01-01

    A bilingual upbringing has been shown to enhance executive control, but the neural mechanisms underpinning such effect are essentially unknown. Here, we investigated whether monolingual and bilingual toddlers differ in semantic processing efficiency and their allocation of attention to expected and unexpected visual stimuli. We simultaneously recorded event-related brain potentials (ERPs) and pupil size in monolingual and bilingual toddlers presented with (spoken) word-picture pairs. Although ERP effects elicited by semantic relatedness were indistinguishable between the two children groups, pictures unrelated to the preceding word evoked greater pupil dilation than related pictures in bilinguals, but not in monolinguals. Furthermore, increasing pupil dilation to unrelated pictures was associated with decreasing N400 amplitude in bilinguals, whereas the monolingual toddlers showed the opposite association. Hence, attention to unexpected stimuli seems to hamper semantic integration in monolinguals, but to facilitate semantic integration in bilinguals, suggesting that bilingual toddlers are more tolerant to variation in word-referent mappings. Given the link between pupil dilation and norepinephrine-driven cognitive efficiency, correlations between ERP amplitude and concurrent pupil dilation provide new insights into the neural bases of the bilingual cognitive advantage. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Infra-slow oscillation (ISO of the pupil size of urethane-anaesthetised rats.

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    Tomasz Blasiak

    Full Text Available Multiplicity of oscillatory phenomena in a range of infra-slow frequencies (<0.01 Hz has been described in mammalian brains at different levels of organisation. The significance and manifestation in physiology and/or behaviour of many brain infra-slow oscillations (ISO remain unknown. Examples of this phenomenon are two types of ISO observed in the brains of urethane-anaesthetised rats: infra-slow, rhythmic changes in the rate of action potential firing in a few nuclei of the subcortical visual system and a sleep-like cycle of activation/deactivation visible in the EEG signal. Because both of these rhythmic phenomena involve brain networks that can influence autonomic nervous system activity, we hypothesised that these two brain ISOs can be reflected by rhythmic changes of pupil size. Thus, in the present study, we used simultaneous pupillography and ECoG recording to verify the hypothesised existence of infra-slow oscillations in the pupil size of urethane-anaesthetised rats. The obtained results showed rhythmic changes in the size of the pupils and rhythmic eyeball movements in urethane-anaesthetised rats. The observed rhythms were characterised by two different dominant components in a range of infra-slow frequencies. First, the long component had a period of ≈ 29 minutes and was present in both the irises and the eyeball movements. Second, the short component had a period of ≈ 2 minutes and was observed only in the rhythmic constrictions and dilations of the pupils. Both ISOs were simultaneously present in both eyes, and they were synchronised between the left and right eye. The long ISO component was synchronised with the cyclic alternations of the brain state, as revealed by rhythmic changes in the pattern of the ECoG signal. Based on the obtained results, we propose a model of interference of ISO present in different brain systems involved in the control of pupil size.

  18. The pupil's response to affective pictures: Role of image duration, habituation, and viewing mode.

    Science.gov (United States)

    Snowden, Robert J; O'Farrell, Katherine R; Burley, Daniel; Erichsen, Jonathan T; Newton, Naomi V; Gray, Nicola S

    2016-08-01

    The pupil has been shown to be sensitive to the emotional content of stimuli. We examined this phenomenon by comparing fearful and neutral images carefully matched in the domains of luminance, image contrast, image color, and complexity of content. The pupil was more dilated after viewing affective pictures, and this effect was (a) shown to be independent of the presentation time of the images (from 100-3,000 ms), (b) not diminished by repeated presentations of the images, and (c) not affected by actively naming the emotion of the stimuli in comparison to passive viewing. Our results show that the emotional modulation of the pupil is present over a range of variables that typically vary from study to study (image duration, number of trials, free viewing vs. task), and encourages the use of pupillometry as a measure of emotional processing in populations where alternative techniques may not be appropriate.

  19. Vision correction for computer users based on image pre-compensation with changing pupil size.

    Science.gov (United States)

    Huang, Jian; Barreto, Armando; Alonso, Miguel; Adjouadi, Malek

    2011-01-01

    Many computer users suffer varying degrees of visual impairment, which hinder their interaction with computers. In contrast with available methods of vision correction (spectacles, contact lenses, LASIK, etc.), this paper proposes a vision correction method for computer users based on image pre-compensation. The blurring caused by visual aberration is counteracted through the pre-compensation performed on images displayed on the computer screen. The pre-compensation model used is based on the visual aberration of the user's eye, which can be measured by a wavefront analyzer. However, the aberration measured is associated with one specific pupil size. If the pupil has a different size during viewing of the pre-compensated images, the pre-compensation model should also be modified to sustain appropriate performance. In order to solve this problem, an adjustment of the wavefront function used for pre-compensation is implemented to match the viewing pupil size. The efficiency of these adjustments is evaluated with an "artificial eye" (high resolution camera). Results indicate that the adjustment used is successful and significantly improves the images perceived and recorded by the artificial eye.

  20. Games, Game Flow, and Gender as They Affect Mathematics Achievement of Pupils in Nigeria

    Directory of Open Access Journals (Sweden)

    A. Aremu

    2016-08-01

    Full Text Available Game flow experience in the use of games has the potential of determining whether games used for learning would achieve the desired goal of improved achievement. With a subject like Mathematics, it is vital to ensure that if game based strategies are to be used, the games must possess this very important construct. Furthermore, the games must be able to produce the flow experience in both males and females, so that the observed gender gap in the learning of the subject would not be further widened. It is therefore important to investigate the gender differences in a game based learning environment for a subject such as Mathematics. This is the purpose of this research. This research investigated games, game flow, and gender as they affect Mathematics achievement of pupils in Nigeria. Through the use of Achievement of Pupils in Fraction-concepts Test (APFT and Game Flow Questionnaire (GFQ, data were collected. The result was a significant difference in mathematics achievements of pupils exposed to game based strategy and those exposed to modified conventional method of teaching. However, there was no significant difference in game flow experiences, as well as in mathematics achievement of male and female pupils exposed to game based strategy.

  1. Reconstruction and analysis of the pupil dilation signal: Application to a psychophysiological affective protocol.

    Science.gov (United States)

    Onorati, Francesco; Barbieri, Riccardo; Mauri, Maurizio; Russo, Vincenzo; Mainardi, Luca

    2013-01-01

    Pupil dilation (PD) dynamics reflect the interactions of sympathetic and parasympathetic innervations in the iris muscle. Different pupillary responses have been observed with respect to emotionally characterized stimuli. Evidences of the correlation between PD and respiration, heart rate variability (HRV) and blood pressure (BP) are present in literature, making the pupil dilation a candidate for estimating the activity state of the Autonomic Nervous System (ANS), in particular during stressful and/or emotionally characterized stimuli. The aim of this study is to investigate whether both slow and fast PD dynamics can be addressed to characterized different affective states. Two different frequency bands were considered: the classical autonomic band [0-0.45] Hz and a very high frequency (VHF) band [0.45-5] Hz. The pupil dilation signals from 13 normal subjects were recorded during a psychological protocol suitable to evoke particular affective states. An elaborate reconstruction of the missing data (blink events and artifacts) was performed to obtain a more reliable signal, particularly in the VHF band. Results show a high correlation between the arousal of the event and the power characteristics of the signal, in all frequencies. In particular, for the "Anger" condition, we can observe 10 indices out of 13 significantly different with respect to "Baseline" counterparts. These preliminary results suggest that both slow and fast oscillations of the PD can be used to characterize affective states.

  2. Effects of aniseikonia, anisometropia, accommodation, retinal illuminance, and pupil size on stereopsis.

    Science.gov (United States)

    Lovasik, J V; Szymkiw, M

    1985-05-01

    The sensitivity of clinical measures of stereoacuity in the detection of interocular differences in retinal images was examined in 50 adults with normal binocularity. Interocular differences in retinal image size (aniseikonia), clarity (anisometropia) and brightness, as well as differences in absolute and relative pupil size (anisocoria) were created in small steps over a large range to determine their effect on threshold levels of stereopsis. Their effect on stereoacuity was measured in both contour (Titmus test) and random dot (Randot test) stereograms. Stereoacuity measured by both types of stereograms decreased in a curvilinear manner for aniseikonic and anisometropic test conditions. Monocular blur caused a more rapid decrease in stereoacuity than induced aniseikonia. Stereoacuity measured by the contour stereogram decreased about 1.8 times faster than that measured by the random dot stereogram during induced aniseikonia and anisometropia. This differential sensitivity suggests that the Titmus test would detect small interocular differences in retinal images more effectively than the Randot test in clinical screening procedures for vision abnormalities. However, both tests can miss clinically significant amounts of aniseikonia and anisometropia, and fail to differentiate the cause of reduced stereopsis. Interocular differences in retinal image brightness and pupil size within a normal physiologic range did not reduce stereopsis to clinically unacceptable levels.

  3. Eyes wide open: Pupil size as a proxy for inhibition in the masked-priming paradigm.

    Science.gov (United States)

    Geller, Jason; Still, Mary L; Morris, Alison L

    2016-05-01

    A core assumption underlying competitive-network models of word recognition is that in order for a word to be recognized, the representations of competing orthographically similar words must be inhibited. This inhibitory mechanism is revealed in the masked-priming lexical-decision task (LDT) when responses to orthographically similar word prime-target pairs are slower than orthographically different word prime-target pairs (i.e., inhibitory priming). In English, however, behavioral evidence for inhibitory priming has been mixed. In the present study, we utilized a physiological correlate of cognitive effort never before used in the masked-priming LDT, pupil size, to replicate and extend behavioral demonstrations of inhibitory effects (i.e., Nakayama, Sears, & Lupker, Journal of Experimental Psychology: Human Perception and Performance, 34, 1236-1260, 2008, Exp. 1). Previous research had suggested that pupil size is a reliable indicator of cognitive load, making it a promising index of lexical inhibition. Our pupillometric data replicated and extended previous behavioral findings, in that inhibition was obtained for orthographically similar word prime-target pairs. However, our response time data provided only a partial replication of Nakayama et al. Journal of Experimental Psychology: Human Perception and Performance, 34, 1236-1260, 2008. These results provide converging lines of evidence that inhibition operates in word recognition and that pupillometry is a useful addition to word recognition researchers' toolbox.

  4. Emotional signals from faces, bodies and scenes influence observers' face expressions, fixations and pupil-size.

    Science.gov (United States)

    Kret, Mariska E; Roelofs, Karin; Stekelenburg, Jeroen J; de Gelder, Beatrice

    2013-01-01

    We receive emotional signals from different sources, including the face, the whole body, and the natural scene. Previous research has shown the importance of context provided by the whole body and the scene on the recognition of facial expressions. This study measured physiological responses to face-body-scene combinations. Participants freely viewed emotionally congruent and incongruent face-body and body-scene pairs whilst eye fixations, pupil-size, and electromyography (EMG) responses were recorded. Participants attended more to angry and fearful vs. happy or neutral cues, independent of the source and relatively independent from whether the face body and body scene combinations were emotionally congruent or not. Moreover, angry faces combined with angry bodies and angry bodies viewed in aggressive social scenes elicited greatest pupil dilation. Participants' face expressions matched the valence of the stimuli but when face-body compounds were shown, the observed facial expression influenced EMG responses more than the posture. Together, our results show that the perception of emotional signals from faces, bodies and scenes depends on the natural context, but when threatening cues are presented, these threats attract attention, induce arousal, and evoke congruent facial reactions.

  5. Salient cues from faces, bodies and scenes influence observers’ face expressions, fixations and pupil size

    Directory of Open Access Journals (Sweden)

    Mariska Esther Kret

    2013-12-01

    Full Text Available We receive emotional signals from different sources, including the face, the whole body and the natural scene. Previous research has shown the importance of context provided by the whole body and the scene context on the recognition of facial expressions. This study measured physiological responses to face-body-scene combinations. Participants viewed emotionally (incongruent face-body and body-scene pairs whilst eye fixations, pupil-size and electromyography (EMG responses were recorded. Participants focused more on angry and fearful vs. happy or neutral cues, independent of the source and relatively independent from emotional incongruence. Moreover, angry faces combined with angry bodies and angry bodies viewed in an aggressive social scene context elicited greatest pupil dilation. Participants' face expressions matched the valence of the stimuli but when face-body compounds were shown, the observed facial expression influenced EMG responses more than the postures. Our results show that threatening signals from faces, bodies and scenes attract attention, induce arousal, and evoke congruent facial reactions.

  6. Summary of an Analysis of Pupil-Teacher Ratio and Class Size: Differences That Make a Difference and Its Implications on Staffing for Class-Size Reduction.

    Science.gov (United States)

    Sharp, Mark A.

    The purpose of this paper was to share findings from an earlier study and to provide a framework for administrators to use in the implementation of class-size reduction (CSR) in their buildings. The study examined actual and average class size (CS), pupil-teacher ratios (PTR), and their differences. A primary goal was to clarify the ramifications…

  7. The Effects of Multimedia Learning on Thai Primary Pupils' Achievement in Size and Depth of Vocabulary Knowledge

    Science.gov (United States)

    Jingjit, Mathukorn

    2015-01-01

    This study aims to obtain more insight regarding the effect of multimedia learning on third grade of Thai primary pupils' achievement in Size and Depth Vocabulary of English. A quasi-experiment is applied using "one group pretest-posttest design" combined with "time series design," as well as data triangulation. The sample…

  8. Effects of pirenzepine on pupil size and accommodation in rhesus monkeys.

    Science.gov (United States)

    Ostrin, Lisa A; Frishman, Laura J; Glasser, Adrian

    2004-10-01

    Pirenzepine is suggested to be a relatively selective muscarinic (M(1)) antagonist and is currently under investigation for the treatment of myopia. Atropine, a nonselective M-type antagonist, is used in the treatment of myopia, but has undesired ocular and systemic side effects. An M(1)-specific antagonist may decrease side effects and remain effective at reducing the progression of myopia. In the current study, the effects of pirenzepine on pupil diameter, resting refraction, and accommodation were studied in rhesus monkeys. The time course and extent of mydriasis from subconjunctival injection of 2% pirenzepine were determined in five normal rhesus monkeys, and the effects on static and dynamic accommodation were determined in four rhesus monkeys with permanent indwelling electrodes in the Edinger-Westphal (EW) nucleus of the midbrain. Subconjunctival injections of 0.0002% to 0.2% pirenzepine in log unit dilutions were tested in three monkeys to determine the effects on static EW-stimulated accommodation. At 40 to 50 minutes after pirenzepine injection, accommodation was stimulated pharmacologically in both eyes, and the response was measured for 30 minutes. After 2% pirenzepine injection, pupil size increased 2.02 +/- 0.41 mm, there was a hyperopic shift in resting refraction of 1.07 +/- 0.23 D, and nearly complete cycloplegia occurred. Maximum EW-stimulated accommodation was significantly decreased 20 to 40 minutes after 0.02% or greater pirenzepine. Carbachol-stimulated accommodation was significantly decreased after 0.2% or greater pirenzepine. Subconjunctival injections of 0.02% or greater pirenzepine result in a significant decrease in accommodation and are probably acting through nonselective muscarinic antagonism. Subconjunctival injections of 0.002% or less pirenzepine do not decrease EW-stimulated accommodation.

  9. The post illumination pupil response is reduced in seasonal affective disorder

    Science.gov (United States)

    Roecklein, Kathryn; Wong, Patricia; Ernecoff, Natalie; Miller, Megan; Donofry, Shannon; Kamarck, Marissa; Wood-Vasey, W. Michael; Franzen, Peter

    2013-01-01

    Individuals with seasonal affective disorder (SAD) may have a decreased retinal sensitivity in the non-image forming light-input pathway. We examined the post illumination pupil response (PIPR) among individuals with SAD and healthy controls to identify possible differences in the melanopsin signaling pathway. We also investigated whether melanopsin gene (OPN4) variations would predict variability in the PIPR. Fifteen SAD and 15 control participants (80% women, mean age 36.7 years, SD = 14.5) were assessed in the fall/winter. Participants were diagnosed based on DSM-IV-TR criteria. Infrared pupillometry was used to measure pupil diameter prior to, during, and after red and blue stimuli. In response to blue light, the SAD group had a reduced PIPR and a lower PIPR percent change relative to controls. The PIPR after the blue stimulus also varied on the basis of OPN4 I394T genotype, but not OPN4 P10L genotype. These findings may indicate that individuals with SAD have a less sensitive light input pathway as measured by the PIPR, leading to differences in neurobiological and behavioral responses such as alertness, circadian photoentrainment, and melatonin release. In addition, this sensitivity may vary based on sequence variations in OPN4, although a larger sample and replication is needed. PMID:23809464

  10. Effect of Single Administration of Coffee on Pupil Size and Ocular Wavefront Aberration Measurements in Healthy Subjects

    Directory of Open Access Journals (Sweden)

    Handan Bardak

    2016-01-01

    Full Text Available No study has so far evaluated the impact of coffee drinking on ocular wavefront aberration (OWA measurements. This study presents novel findings regarding the OWA of the eye following coffee intake. We aimed to evaluate the acute changes in pupil size and OWA of the eye after single administration of coffee. A total of 30 otherwise healthy participants were included in this prospective study. All subjects drank a cup of coffee containing 57 mg caffeine. Measurements of pupil size, total coma (TC, total trefoil (TF, total spherical aberration (TSA, and total higher order aberration (HOA were performed before and at 5 minutes, at 30 minutes, and at 4 hours after coffee drinking using a wavefront aberrometer device (Irx3, Imagine Eyes, Orsay, France. The mean age of the study population was 20.30 ± 2.74 years. Pupil size did not show a significant change during the measurements (p>0.05. A significant increase was observed in TF and HOA measurements following coffee intake (p=0.029 and p=0.009, resp.. Single administration of coffee results in significant increase in TF and total HOAs in healthy subjects without any effect on pupil diameter. Ultrastructural changes in the cornea following coffee intake might be of relevance to the alterations in ocular aberrations in healthy subjects.

  11. Pupil-size asymmetry is a physiologic trait related to gender, attentional function, and personality.

    Science.gov (United States)

    Poynter, William D

    2016-12-14

    A small difference in the size of the two pupils is common in healthy individuals, a condition termed benign or physiologic anisocoria (BA). Past research indicates that BA is probably caused by asymmetry in sympathetic nervous system (SNS) function [e.g., Rosenberg (2008). Physiologic anisocoria: A manifestation of a physiologic sympathetic asymmetry. Neuro-Ophthalmology, 32, 147-149]. This study is the first to show that BA varies with psychological factors linked to brain asymmetry and autonomic arousal, including gender, attention, and personality. Males exhibited a more directional BA than females, consistent with greater hemispheric lateralization in males. BA also varied with a self-report measure of attentional function, consistent with evidence of hemispheric asymmetry in visuospatial attention networks. Finally, BA varied with personality traits linked to autonomic arousal. Individuals exhibiting higher Meanness and Boldness, and lower Empathy scores tended to show more directional BA. This link between personality traits and BA may be related to brain asymmetries in autonomic arousal and emotion-related processing. If future studies employing direct measures of lateralized brain activity confirm the link between BA and SNS asymmetries, this new metric may prove useful in discovering new relationships between brain organization and psychological function, and how these relationships vary across individuals.

  12. An attempt to understand flicker vertigo: changes in pupil size and choroidal blood flow under flickering conditions

    Science.gov (United States)

    Masi, Maria Gabriella; Peretto, Lorenzo; Rovati, Luigi; Ansari, Rafat R.

    2010-02-01

    Light flickering at a rate of 4- 20 cycles per second can produce unpleasant reactions such as nausea and vertigo. In this paper, the possibility of achieving an objective evaluation/prediction of the physiological effects induced by flicker is investigated using a new imaging method based on the pupil size determination. This method is also compared with the blood flow analysis in the choroid.

  13. Influence of ocular chromatic aberration and pupil size on transverse resolution in ophthalmic adaptive optics optical coherence tomography.

    Science.gov (United States)

    Fernández, Enrique; Drexler, Wolfgang

    2005-10-03

    Optical coherence tomography (OCT) enables visualization of the living human retina with unprecedented high axial resolution. The transverse resolution of existing OCT approaches is relatively modest as compared to other retinal imaging techniques. In this context, the use of adaptive optics (AO) to correct for ocular aberrations in combination with OCT has recently been demonstrated to notably increase the transverse resolution of the retinal OCT tomograms. AO is required when imaging is performed through moderate and large pupil sizes. A fundamental difference of OCT as compared to other imaging techniques is the demand of polychromatic light to accomplish high axial resolution. In ophthalmic OCT applications, the performance is therefore also limited by ocular chromatic aberrations. In the current work, the effects of chromatic and monochromatic ocular aberrations on the quality of retinal OCT tomograms, especially concerning transverse resolution, sensitivity and contrast, are theoretically studied and characterized. The repercussion of the chosen spectral bandwidth and pupil size on the final transverse resolution of OCT tomograms is quantitatively examined. It is found that losses in the intensity of OCT images obtained with monochromatic aberration correction can be up to 80 %, using a pupil size of 8 mm diameter in combination with a spectral bandwidth of 120 nm full width at half maximum for AO ultrahigh resolution OCT. The limits to the performance of AO for correction of monochromatic aberrations in OCT are established. The reduction of the detected signal and the resulting transverse resolution caused by chromatic aberration of the human eye is found to be strongly dependent on the employed bandwidth and pupil size. Comparison of theoretical results with experimental findings obtained in living human eyes is also provided.

  14. Ocular accommodation and cognitive demand: An additional indicator besides pupil size and cardiovascular measures?

    Directory of Open Access Journals (Sweden)

    Jaschinski Wolfgang

    2008-08-01

    Full Text Available Abstract Background The aim of the present study was to assess accommodation as a possible indicator of changes in the autonomic balance caused by altered cognitive demand. Accounting for accommodative responses from a human factors perspective may be motivated by the interest of designing virtual image displays or by establishing an autonomic indicator that allows for remote measurement at the human eye. Heart period, pulse transit time, and the pupillary response were considered as reference for possible closed-loop accommodative effects. Cognitive demand was varied by presenting monocularly numbers at a viewing distance of 5 D (20 cm which had to be read, added or multiplied; further, letters were presented in a "n-back" task. Results Cardiovascular parameters and pupil size indicated a change in autonomic balance, while error rates and reaction time confirmed the increased cognitive demand during task processing. An observed decrease in accommodation could not be attributed to the cognitive demand itself for two reasons: (1 the cognitive demand induced a shift in gaze direction which, for methodological reasons, accounted for a substantial part of the observed accommodative changes. (2 Remaining effects disappeared when the correctness of task processing was taken into account. Conclusion Although the expectation of accommodation as possible autonomic indicator of cognitive demand was not confirmed, the present results are informative for the field of applied psychophysiology noting that it seems not to be worthwhile to include closed-loop accommodation in future studies. From a human factors perspective, expected changes of accommodation due to cognitive demand are of minor importance for design specifications – of, for example, complex visual displays.

  15. Pupil Center as a Function of Pupil Diameter

    DEFF Research Database (Denmark)

    Ahmed, Zaheer; Mardanbegi, Diako; Hansen, Dan Witzner

    2016-01-01

    We investigate the gaze estimation error induced by pupil size changes using simulated data. We investigate the influence of pupil diameter changes on estimated gaze point error obtained by two gaze estimation models. Simulation data show that at wider viewing angles and at small eye......-camera distances, error increases with increasing pupil sizes. The maximum error recorded for refracted pupil images is 2.4° of visual angle and 1.5° for non-refracted pupil projections....

  16. PARAMETERS AFFECTING PARTICLE SIZE OF POLYBUTYLACRYLATE MICROGELS

    Institute of Scientific and Technical Information of China (English)

    WANG Xia; YU Yunzhao

    1989-01-01

    The factors affecting particle size of reactive microgels formed during the self-emulsifying copolymerization of unsaturated polyester (UP )with butyl acrylate (BA)have been studied. The parameters discussed are: the proportion of the UP in the monomer mixture, the molecular weight and the carboxyl value of the UP, the phase ratio, the electrolyte concentration and the polar solvent additive. The seeding emulsion polymerization is discussed as well. It turned out that the particle size of the reactive microgels can be controlled in a definite range by changing the experimental conditions. However the particle size distribution becomes broader as the average diameter increases. It is suggested that the agglomeration of primary particles plays an important role during the growth of microgel particle.

  17. The effect of pupil size on stimulation of the melanopsin containing retinal ganglion cells, as evaluated by monochromatic pupillometry

    DEFF Research Database (Denmark)

    Nissen, Claus Jeppe; Sander, Birgit; Lund-Andersen, Henrik

    2012-01-01

    Purpose: To evaluate the influence of the size of the light exposed pupil in one eye on the pupillary light reflex of the other eye. Method: Using a monochromatic pupillometer, the left eye in each of 10 healthy subjects was exposed to 20¿s of monochromatic light of luminance 300¿cd/m(2), first red...... (660¿nm) and in a following session, blue (470¿nm) light. The consensual pupillary diameter in the right eye was continuously measured before, during, and after light exposure. Subsequently, Tropicamide 1% or Pilocarpine 2% was instilled into the left eye and when the pupil was either maximally dilated...... or contracted, the entire sequence of red and blue light exposure repeated. After at least 3¿days, when the effect of the eye drop had subsided, the entire experiment was repeated, this time employing the other substance. Results: Prior dilatation of the left pupil augmented the post light contraction to blue...

  18. A neural network method for detection of obstructive sleep apnea and narcolepsy based on pupil size and EEG.

    Science.gov (United States)

    Liu, D; Pang, Z; Lloyd, S R

    2008-02-01

    Electroencephalogram (EEG) is able to indicate states of mental activity ranging from concentrated cognitive efforts to sleepiness. Such mental activity can be reflected by EEG energy. In particular, intrusion of EEG theta wave activity into the beta activity of active wakefulness has been interpreted as ensuing sleepiness. Pupil behavior can also provide information regarding alertness. This paper develops an innovative signal classification method that is capable of differentiating subjects with sleep disorders which cause excessive daytime sleepiness (EDS) from normal control subjects who do not have a sleep disorder based on EEG and pupil size. Subjects with sleep disorders include persons with untreated obstructive sleep apnea (OSA) and narcolepsy. The Yoss pupil staging rule is used to scale levels of wakefulness and at the same time theta energy ratios are calculated from the same 2-s sliding windows by Fourier or wavelet transforms. Then, an artificial neural network (NN) of modified adaptive resonance theory (ART2) is utilized to identify the two groups within a combined group of subjects including those with OSA and healthy controls. This grouping from the NN is then compared with the actual diagnostic classification of subjects as OSA or controls and is found to be 91% accurate in differentiating between the two groups. The same algorithm results in 90% correct differentiation between narcoleptic and control subjects.

  19. Factors Affecting Pupils' Noise Annoyance in Schools: The Building and Testing of Models

    Science.gov (United States)

    Boman, Eva; Enmarker, Ingela

    2004-01-01

    This article reports two studies intended to develop and assess conceptual models of how different factors mediate and moderate the annoyance reaction in school environments. In the first, a survey of 207 pupils was conducted where assumptions about mediators and moderators were formulated and tested. In the best model, general sensitivity and…

  20. Interval Size and Affect: An Ethnomusicological Perspective

    Directory of Open Access Journals (Sweden)

    Sarha Moore

    2013-08-01

    Full Text Available This commentary addresses Huron and Davis's question of whether "The Harmonic Minor Provides an Optimum Way of Reducing Average Melodic Interval Size, Consistent with Sad Affect Cues" within any non-Western musical cultures. The harmonic minor scale and other semitone-heavy scales, such as Bhairav raga and Hicaz makam, are featured widely in the musical cultures of North India and the Middle East. Do melodies from these genres also have a preponderance of semitone intervals and low incidence of the augmented second interval, as in Huron and Davis's sample? Does the presence of more semitone intervals in a melody affect its emotional connotations in different cultural settings? Are all semitone intervals equal in their effect? My own ethnographic research within these cultures reveals comparable connotations in melodies that linger on semitone intervals, centered on concepts of tension and metaphors of falling. However, across different musical cultures there may also be neutral or lively interpretations of these same pitch sets, dependent on context, manner of performance, and tradition. Small pitch movement may also be associated with social functions such as prayer or lullabies, and may not be described as "sad." "Sad," moreover may not connote the same affect cross-culturally.

  1. Human place and response learning: navigation strategy selection, pupil size and gaze behavior.

    Science.gov (United States)

    de Condappa, Olivier; Wiener, Jan M

    2016-01-01

    In this study, we examined the cognitive processes and ocular behavior associated with on-going navigation strategy choice using a route learning paradigm that distinguishes between three different wayfinding strategies: an allocentric place strategy, and the egocentric associative cue and beacon response strategies. Participants approached intersections of a known route from a variety of directions, and were asked to indicate the direction in which the original route continued. Their responses in a subset of these test trials allowed the assessment of strategy choice over the course of six experimental blocks. The behavioral data revealed an initial maladaptive bias for a beacon response strategy, with shifts in favor of the optimal configuration place strategy occurring over the course of the experiment. Response time analysis suggests that the configuration strategy relied on spatial transformations applied to a viewpoint-dependent spatial representation, rather than direct access to an allocentric representation. Furthermore, pupillary measures reflected the employment of place and response strategies throughout the experiment, with increasing use of the more cognitively demanding configuration strategy associated with increases in pupil dilation. During test trials in which known intersections were approached from different directions, visual attention was directed to the landmark encoded during learning as well as the intended movement direction. Interestingly, the encoded landmark did not differ between the three navigation strategies, which is discussed in the context of initial strategy choice and the parallel acquisition of place and response knowledge.

  2. How Class Size Reduction Mediates Secondary Students' Learning: Hearing the Pupil Voice

    Science.gov (United States)

    Harfitt, Gary James

    2012-01-01

    This paper discusses the question of why and how class size can make a difference to teaching and learning from the students' perspective. Secondary school contexts and, in particular, the students' own voice on the issue of class size represent an under-researched area for class size studies. This paper draws on data from three case studies that…

  3. Plate size does not affect perception of food portion size.

    Science.gov (United States)

    Penaforte, F R O; Japur, C C; Diez-Garcia, R W; Hernandez, J C; Palmma-Linares, I; Chiarello, P G

    2014-04-01

    Evidences have suggested that larger utensils may provoke 'size-contrast illusions', influencing the perceived volume and food consumption. To analyse the influence of plate size on the visual estimate of food portion size. Two 400 g portions of pasta with tomato sauce were presented on two plates of different diameters (24.0 and 9.0 cm). Each participant visually estimated on an individual basis the quantities of the pasta portions (g) present on each plate. In addition, each subject classified the size of the portions on each plate as 'small', 'medium' and 'large'. The mean estimates of the amount of pasta on each plate were compared by the nonparametric Mann-Whitney. The differences in the frequencies of portion classifications between plates were evaluated by the chi-squared test. Forty-eight students (average 25.8 ± 8.9 years) participated in the study. There was no difference in the median amount of pasta estimated for the large and small plates (150 g; range 50-500 and 115 g; range 40-500 g, respectively). The classification of the portion size as 'large' was reported by a significantly greater number of persons when they evaluated the amount of pasta arranged on the large plate compared to the small plate (47.9 versus 22.9%, respectively; P = 0.018). The size of the plate did not influence the estimate of food portions, even though it did influence the classification of portion size. © 2013 The Authors Journal of Human Nutrition and Dietetics © 2013 The British Dietetic Association Ltd.

  4. Does Sibship Size Affect Educational Attainment?

    DEFF Research Database (Denmark)

    Jæger, Mads Meier

    This paper implements a test of the Resource Dilution Hypothesis (RDH) stating that sibship size has a negative causal effect on educational attainment. Most existing studies using conventional methods support the RDH. This paper implements an Instrumental Variable (IV) approach to testing...... the claim of a negative causal relationship between sibship size and educational attainment. Analyzing data from the Wisconsin Longitudinal Study, the empirical analysis demonstrates, first, that conventional OLS regression estimates sibship size to have a negative effect on educational attainment equal...

  5. Optimal timing of retinal scanning during dark adaptation, in the presence of fixation on a target: the role of pupil size dynamics

    Science.gov (United States)

    Gramatikov, Boris I.; Irsch, Kristina; Guyton, David

    2014-10-01

    While validating our newly developed vision screener based on a double-pass retinal scanning system, we noticed that in all patients the signals from the retina were significantly higher when measurements were performed within a certain time interval referenced to the initial moment when the lights were dimmed and the test subject was asked to fixate on a target. This appeared to be most likely attributable to pupil size dynamics and triggered the present study, whose aim was to assess the pupillary "lights-off" response while fixating on a target in the presence of an accommodative effort. We found that pupil size increases in the first 60 to 70 s after turning off the room lights, and then it decreases toward the baseline in an exponential decay. Our results suggest that there is an optimal time window during which pupil size is expected to be maximal, that is during the second minute after dimming the room lights. During this time, window retinal diagnostic instruments based on double-pass measurement technology should deliver an optimal signal-to-noise ratio. We also propose a mathematical model that can be used to approximate the behavior of the normalized pupil size.

  6. Nevada's Class-Size Reduction Program. Nevada Revised Statutes 388.700-388.730: "Program To Reduce the Pupil-Teacher Ratio." Background Paper 97-7.

    Science.gov (United States)

    Sturm, H. Pepper

    In 1989, the Nevada Legislature enacted the Class-Size Reduction (CSR) Act. The measure was designed to reduce the pupil-teacher ratio in the public schools, particularly in the earliest grades. The program was scheduled to proceed in several phases. The first step reduced the student-teacher ratio in selected kindergartens and first grade classes…

  7. Optimal timing of retinal scanning during dark adaptation, in the presence of fixation on a target: the role of pupil size dynamics.

    Science.gov (United States)

    Gramatikov, Boris I; Irsch, Kristina; Guyton, David

    2014-01-01

    While validating our newly developed vision screener based on a double-pass retinal scanning system, we noticed that in all patients the signals from the retina were significantly higher when measurements were performed within a certain time interval referenced to the initial moment when the lights were dimmed and the test subject was asked to fixate on a target. This appeared to be most likely attributable to pupil size dynamics and triggered the present study, whose aim was to assess the pupillary “lights-off” response while fixating on a target in the presence of an accommodative effort. We found that pupil size increases in the first 60 to 70 s after turning off the room lights, and then it decreases toward the baseline in an exponential decay. Our results suggest that there is an optimal time window during which pupil size is expected to be maximal, that is during the second minute after dimming the room lights. During this time, window retinal diagnostic instruments based on double-pass measurement technology should deliver an optimal signal-to-noise ratio. We also propose a mathematical model that can be used to approximate the behavior of the normalized pupil size.

  8. Time-domain analysis for extracting fast-paced pupil responses

    Science.gov (United States)

    Zénon, Alexandre

    2017-01-01

    The eye pupil reacts to cognitive processes, but its analysis is challenging when luminance varies or when stimulation is fast-paced. Current approaches relying on deconvolution techniques do not account for the strong low-frequency spontaneous changes in pupil size or the large interindividual variability in the shape of the responses. Here a system identification framework is proposed in which the pupil responses to different parameters are extracted by means of an autoregressive model with exogenous inputs. In an example application of this technique, pupil size was shown to respond to the luminance and arousal scores of affective pictures presented in rapid succession. This result was significant in each subject (N = 5), but the pupil response varied between individuals both in amplitude and latency, highlighting the need for determining impulse responses subjectwise. The same method was also used to account for pupil size variations caused by respiration, illustrating the possibility to model the relation between pupil size and other continuous signals. In conclusion, this new framework for the analysis of pupil size data allows us to dissociate the response of the eye pupil from intermingled sources of influence and can be used to study the relation between pupil size and other physiological signals. PMID:28134323

  9. Does Sibship Size Affect Educational Attainment?

    DEFF Research Database (Denmark)

    Jæger, Mads Meier

    This paper implements a test of the Resource Dilution Hypothesis (RDH) stating that sibship size has a negative causal effect on educational attainment. Most existing studies using conventional methods support the RDH. This paper implements an Instrumental Variable (IV) approach to testing the cl...

  10. The effect of intracameral epinephrine on pupil size during phacoemulsification and its postoperative effect on specular findings and macular thickness

    Directory of Open Access Journals (Sweden)

    Hassan Gamal El-Din Farahat

    Full Text Available ABSTRACT Objective: To evaluate pupillary size and vital signs following intraoperative intracameral adrenaline during phacoemulsification and postoperative effect of on co specular microscopy findings and macular thickness by OCT. Methods: A prospective interventional study carried out from December 2014 to December 2015 on 90 eyes. They were divided randomly into further 6 groups (15 each. The inclusion criteria consisted of no history of ocular pathologic conditions, trauma, previous ocular surgery, or recent ocular medication use. All patients were dilated preoperatively by phenylephrine 10% and operated under local peribulbar anesthesia. Then systemic monitoring regarding (pulse rate, blood pressure and measurement of the horizontal pupil diameter by a caliper to the nearest 0.25mm pre and post intracameral adrenaline injection. Results: In our study there were great effect for intracameral epinephrine, with concentrations used, in dilatation and maintainance of papillary dilatation, The mean pre intracameral epinephrine was 4.53± 1.27 mm.The mean post epinephrine papillary diameter was 6.46± 1.00 mm. Three cases from group 1/10000 weren't dilated properly. Also three cases from group 1/9000 weren't dilated properly after intracameral epinephrine. Conclusion: Intracameral epinephrine even in higher concentrations is effective in papillary dilatation especially in cases with long duration and poorly dilated cases by usual topical mydriatics.

  11. Effect of the hypomagnetic field on the size of the eye pupil

    OpenAIRE

    Binhi, Vladimir N.; Sarimov, Ruslan M.

    2013-01-01

    Previously, we reported that the hypomagnetic field obtained by the 100-fold deprivation of the geomagnetic field affected human cognitive processes as estimated in several computer tests. The exposure to the hypomagnetic field caused a statistically significant increase both in the task processing time and in the number of errors. The magnitude of this magnetic effect, averaged over 40 healthy subjects and more than 10^5 separate trials, was about 1.7%. In the present work, the results of a ...

  12. Pupil size signals mental effort deployed during multiple object tracking and predicts brain activity in the dorsal attention network and the locus coeruleus.

    Science.gov (United States)

    Alnæs, Dag; Sneve, Markus Handal; Espeseth, Thomas; Endestad, Tor; van de Pavert, Steven Harry Pieter; Laeng, Bruno

    2014-04-01

    Attentional effort relates to the allocation of limited-capacity attentional resources to meet current task demands and involves the activation of top-down attentional systems in the brain. Pupillometry is a sensitive measure of this intensity aspect of top-down attentional control. Studies relate pupillary changes in response to cognitive processing to activity in the locus coeruleus (LC), which is the main hub of the brain's noradrenergic system and it is thought to modulate the operations of the brain's attentional systems. In the present study, participants performed a visual divided attention task known as multiple object tracking (MOT) while their pupil sizes were recorded by use of an infrared eye tracker and then were tested again with the same paradigm while brain activity was recorded using fMRI. We hypothesized that the individual pupil dilations, as an index of individual differences in mental effort, as originally proposed by Kahneman (1973), would be a better predictor of LC activity than the number of tracked objects during MOT. The current results support our hypothesis, since we observed pupil-related activity in the LC. Moreover, the changes in the pupil correlated with activity in the superior colliculus and the right thalamus, as well as cortical activity in the dorsal attention network, which previous studies have shown to be strongly activated during visual tracking of multiple targets. Follow-up pupillometric analyses of the MOT task in the same individuals also revealed that individual differences to cognitive load can be remarkably stable over a lag of several years. To our knowledge this is the first study using pupil dilations as an index of attentional effort in the MOT task and also relating these to functional changes in the brain that directly implicate the LC-NE system in the allocation of processing resources.

  13. Tonic pupil in leprosy

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Lana-Peixoto

    2014-12-01

    Full Text Available Pupil abnormalities in leprosy usually result from chronic iritis with loss of stroma, iris miosis, a sluggish reaction to light, and poor dilation in response to anticholinergic mydriatics. We report two patients with long-standing lepromatous leprosy who developed tonic pupils characterized by mydriasis, absence of reaction to light and hypersensitivity to weak cholinergic solution. Examination revealed iritis and iris atrophy. In both cases, instillation of dilute 0.1% pilocarpine caused miosis in the affected eyes. Tonic pupil occurs in many conditions, but its association with leprosy had not been previously reported.

  14. Decision-related pupil dilation reflects upcoming choice and individual bias.

    Science.gov (United States)

    de Gee, Jan Willem; Knapen, Tomas; Donner, Tobias H

    2014-02-04

    A number of studies have shown that pupil size increases transiently during effortful decisions. These decision-related changes in pupil size are mediated by central neuromodulatory systems, which also influence the internal state of brain regions engaged in decision making. It has been proposed that pupil-linked neuromodulatory systems are activated by the termination of decision processes, and, consequently, that these systems primarily affect the postdecisional brain state. Here, we present pupil results that run contrary to this proposal, suggesting an important intradecisional role. We measured pupil size while subjects formed protracted decisions about the presence or absence ("yes" vs. "no") of a visual contrast signal embedded in dynamic noise. Linear systems analysis revealed that the pupil was significantly driven by a sustained input throughout the course of the decision formation. This sustained component was larger than the transient component during the final choice (indicated by button press). The overall amplitude of pupil dilation during decision formation was bigger before yes than no choices, irrespective of the physical presence of the target signal. Remarkably, the magnitude of this pupil choice effect (yes > no) reflected the individual criterion: it was strongest in conservative subjects choosing yes against their bias. We conclude that the central neuromodulatory systems controlling pupil size are continuously engaged during decision formation in a way that reveals how the upcoming choice relates to the decision maker's attitude. Changes in brain state seem to interact with biased decision making in the face of uncertainty.

  15. Evaluation of Factors Affecting Size and Size Distribution of Chitosan-Electrosprayed Nanoparticles.

    Science.gov (United States)

    Abyadeh, Morteza; Karimi Zarchi, Ali Akbar; Faramarzi, Mohammad Ali; Amani, Amir

    2017-01-01

    Size and size distribution of polymeric nanoparticles have important effect on their properties for pharmaceutical application. In this study, Chitosan nanoparticles were prepared by electrospray method (electrohydrodynamic atomization) and parameters that simultaneously affect size and/or size distribution of chitosan nanoparticles were optimized. Effect of formulation/processing three independent formulation/processing parameters, namely concentration, flow rate and applied voltage was investigated on particle size and size distribution of generated nanoparticles using a Box-Behnken experimental design. All the studied factors showed important effects on average size and size distribution of nanoparticles. A decrease in size and size distribution was obtainable with decreasing flow rate and concentration and increasing applied voltage. Eventually, a sample with minimum size and polydispersity was obtained with polymer concentration, flow rate and applied voltage values of 0.5 %w/v, 0.05 ml/hr and 15 kV, respectively. The experimentally prepared nanoparticles, expected having lowest size and size distribution values had a size of 105 nm, size distribution of 36 and Zeta potential of 59.3 mV. Results showed that optimum condition for production of chitosan nanoparticles with the minimum size and narrow size distribution was a minimum value for flow rate and highest value for applied voltage along with an optimum chitosan concentration.

  16. Appropriate Pupilness

    DEFF Research Database (Denmark)

    Kofoed, Jette

    2008-01-01

    The analytical focus in this article is on how social categories intersect in daily school life and how intersections intertwine with other empirically relevant categories such as normality, pupilness and (in)appropriatedness. The point of empirical departure is a daily ritual where teams...... for football are selected. The article opens up for a microanalysis of everyday practices at the margins and at the core of what this article terms `pupilness'. The concept of intersectionality is suggested as a useful analytical tool to understand the multiple activities of pupils in everyday school life...

  17. Does pupil constriction under blue and green monochromatic light exposure change with age?

    Science.gov (United States)

    Daneault, Véronique; Vandewalle, Gilles; Hébert, Marc; Teikari, Petteri; Mure, Ludovic S; Doyon, Julien; Gronfier, Claude; Cooper, Howard M; Dumont, Marie; Carrier, Julie

    2012-06-01

    Many nonvisual functions are regulated by light through a photoreceptive system involving melanopsin-expressing retinal ganglion cells that are maximally sensitive to blue light. Several studies have suggested that the ability of light to modulate circadian entrainment and to induce acute effects on melatonin secretion, subjective alertness, and gene expression decreases during aging, particularly for blue light. This could contribute to the documented changes in sleep and circadian regulatory processes with aging. However, age-related modification in the impact of light on steady-state pupil constriction, which regulates the amount of light reaching the retina, is not demonstrated. We measured pupil size in 16 young (22.8±4 years) and 14 older (61±4.4 years) healthy subjects during 45-second exposures to blue (480 nm) and green (550 nm) monochromatic lights at low (7×10(12) photons/cm2/s), medium (3×10(13) photons/cm2/s), and high (10(14) photons/cm2/s) irradiance levels. Results showed that young subjects had consistently larger pupils than older subjects for dark adaptation and during all light exposures. Steady-state pupil constriction was greater under blue than green light exposure in both age groups and increased with increasing irradiance. Surprisingly, when expressed in relation to baseline pupil size, no significant age-related differences were observed in pupil constriction. The observed reduction in pupil size in older individuals, both in darkness and during light exposure, may reduce retinal illumination and consequently affect nonvisual responses to light. The absence of a significant difference between age groups for relative steady-state pupil constriction suggests that other factors such as tonic, sympathetic control of pupil dilation, rather than light sensitivity per se, account for the observed age difference in pupil size regulation. Compared to other nonvisual functions, the light sensitivity of steady-state pupil constriction appears to

  18. Does pupil constriction under blue and green monochromatic light exposure change with age?

    Science.gov (United States)

    Daneault, Véronique; Vandewalle, Gilles; Hébert, Marc; Teikari, Petteri; Mure, Ludovic S.; Doyon, Julien; Gronfier, Claude; Cooper, Howard M.; Dumont, Marie; Carrier, Julie

    2017-01-01

    Many non-visual functions are regulated by light through a photoreceptive system involving melanopsin-expressing retinal ganglion cells that are maximally sensitive to blue light. Several studies have suggested that the ability of light to modulate circadian entrainment and to induce acute effects on melatonin secretion, subjective alertness and gene expression, decreases during aging, particularly for blue light. This could contribute to the documented changes in sleep and circadian regulatory processes with aging. However, age-related modification in the impact of light on steady-state pupil constriction, which regulates the amount of light reaching the retina, is not demonstrated. We measured pupil size in 16 young (22.8±4y) and 14 older (61±4.4y) healthy subjects during 45s exposures to blue (480nm) and green (550nm) monochromatic lights at low (7×1012 photons/cm2/s), medium (3×1013 photons/cm2/s), and high (1014 photons/cm2/s) irradiance levels. Results showed that young subjects had consistently larger pupils than older subjects, for dark adaptation and during all light exposures. Steady-state pupil constriction was greater under blue than green light exposure in both age groups and increased with increasing irradiance. Surprisingly, when expressed in relation to baseline pupil size, no significant age-related differences were observed in pupil constriction. The observed reduction in pupil size in older individuals, both in darkness and during light exposure, may reduce retinal illumination and consequently affect non-visual responses to light. The absence of a significant difference between age groups for relative steady-state pupil constriction suggests that other factors such as tonic, sympathetic control of pupil dilation, rather than light sensitivity per se, account for the observed age difference in pupil size regulation. Compared to other nonvisual functions, the light sensitivity of steady-state pupil constriction appears to remain relatively

  19. Sneaker Males Affect Fighter Male Body Size and Sexual Size Dimorphism in Salmon.

    Science.gov (United States)

    Weir, Laura K; Kindsvater, Holly K; Young, Kyle A; Reynolds, John D

    2016-08-01

    Large male body size is typically favored by directional sexual selection through competition for mates. However, alternative male life-history phenotypes, such as "sneakers," should decrease the strength of sexual selection acting on body size of large "fighter" males. We tested this prediction with salmon species; in southern populations, where sneakers are common, fighter males should be smaller than in northern populations, where sneakers are rare, leading to geographical clines in sexual size dimorphism (SSD). Consistent with our prediction, fighter male body size and SSD (fighter male∶female size) increase with latitude in species with sneaker males (Atlantic salmon Salmo salar and masu salmon Oncorhynchus masou) but not in species without sneakers (chum salmon Oncorhynchus keta and pink salmon Oncorhynchus gorbuscha). This is the first evidence that sneaker males affect SSD across populations and species, and it suggests that alternative male mating strategies may shape the evolution of body size.

  20. Teachers' and Pupils' Behavior in Large and Small Classes: A Systematic Observation Study of Pupils Aged 10 and 11 Years

    Science.gov (United States)

    Blatchford, Peter; Bassett, Paul; Brown, Penelope

    2005-01-01

    The authors examined class size effects on teacher-pupil interactions, pupil engagement, and pupil-pupil interaction. They extended previous research by recognizing the hierarchical nature of observation data and the possible influence of other variables. The study used a time sampling method involving 257 children (aged 10-11 years) in 16 small…

  1. 驾车接近隧道过程中驾驶员瞳孔大小变化规律%Changing rule of drivers’pupil size as driving into tunnels

    Institute of Scientific and Technical Information of China (English)

    胡英奎; 陈仲林; 张青文; 翁季; 黄珂

    2015-01-01

    为了解驾驶员驾车进入隧道过程中的瞳孔变化过程,让8位驾驶员分别驾车进入4座隧道,在此过程中用眼动仪记录驾驶员的瞳孔大小。分析眼动仪记录得到的驾驶员瞳孔大小数据的特征,通过小波变换进行数据处理,得到了驾驶员驾车进入隧道过程中瞳孔大小变化曲线。分析驾驶员瞳孔大小变化曲线发现,不同驾驶员的瞳孔大小存在个体差异;同一驾驶员多次测试的瞳孔大小存在一定的随机性;在接近隧道过程中驾驶员瞳孔逐渐变大,并在隧道洞口附近急剧变大;不同驾驶员的瞳孔变化趋势存在一定的差异;驾驶员瞳孔大小除受适应亮度的影响外,还受驾驶员的心理等因素的影响。%To reveal the changing process of drivers’pupil size during driving were carried out into of tunnels, experiments eight drivers drived into four tunnels at different time.And their pupil size were recorded with eye tracker in the driving process.The recorded raw data by eye tracker was analyzed,wavelet transforms method was taken to process the data,and the pupil size changing curves of drivers when they drive into tunnels.From the curves analysis,it has been found that the individual difference exist on different drivers’pupil size;There was a degree of randomness of pupil sizes amone repeated test of the same driver;the drivers’pupil enlarged gradually when they driving into tunnels,and enlarged violently nearby tunnel’s threshold;the pupil size changing tendency of different driver exists some difference;drivers’pupil size was influence not only by adaptation luminance,but also by their psychological factors.

  2. Methodology significantly affects genome size estimates: quantitative evidence using bryophytes.

    Science.gov (United States)

    Bainard, Jillian D; Fazekas, Aron J; Newmaster, Steven G

    2010-08-01

    Flow cytometry (FCM) is commonly used to determine plant genome size estimates. Methodology has improved and changed during the past three decades, and researchers are encouraged to optimize protocols for their specific application. However, this step is typically omitted or undescribed in the current plant genome size literature, and this omission could have serious consequences for the genome size estimates obtained. Using four bryophyte species (Brachythecium velutinum, Fissidens taxifolius, Hedwigia ciliata, and Thuidium minutulum), three methodological approaches to the use of FCM in plant genome size estimation were tested. These included nine different buffers (Baranyi's, de Laat's, Galbraith's, General Purpose, LB01, MgSO(4), Otto's, Tris.MgCl(2), and Woody Plant), seven propidium iodide (PI) staining periods (5, 10, 15, 20, 45, 60, and 120 min), and six PI concentrations (10, 25, 50, 100, 150, and 200 microg ml(-1)). Buffer, staining period and staining concentration all had a statistically significant effect (P = 0.05) on the genome size estimates obtained for all four species. Buffer choice and PI concentration had the greatest effect, altering the 1C-values by as much as 8% and 14%, respectively. As well, the quality of the data varied with the different methodology used. Using the methodology determined to be the most accurate in this study (LB01 buffer and PI staining for 20 min at 150 microg ml(-1)), three new genome size estimates were obtained: B. velutinum: 0.46 pg, H. ciliata: 0.30 pg, and T. minutulum: 0.46 pg. While the peak quality of flow cytometry histograms is important, researchers must consider that changes in methodology can also affect the relative peak positions and therefore the genome size estimates obtained for plants using FCM.

  3. Quantitative assessment of the impact of blood pulsation on images of the pupil in infrared light.

    Science.gov (United States)

    Koprowski, Robert; Szmigiel, Marta; Kasprzak, Henryk; Wróbel, Zygmunt; Wilczyński, Sławomir

    2015-08-01

    Pulsation in the blood vessels of the eye has a big impact on the dynamics of the entire eyeball and its individual elements. Blood pulsation in the retina can be recorded by the pupil, whose size is also subject to dynamic changes. The study involved synchronous measurements of pupil size using a high-speed camera, and blood pulsation using a pulse oximeter placed on the ear lobe. In addition, there were no metrologically significant differences in the phase shift between the average brightness of the individual pupil quadrants. Blood pulsation in other ocular tissues can affect the dynamics of the optical properties of the eye. As demonstrated in this paper, it affects the pupil behavior and its parameters to a considerable extent.

  4. The Effects of Large Class Size on Effective EFL Teaching and Learning--A Study of Grade 10 Teachers and Pupils at "Instituto Médio Politécnico do Namibe?

    Science.gov (United States)

    Sangangula, Londaka Amasio

    2016-01-01

    The purpose of this study was to provide views of teachers and pupils on large class size and its effects on teaching and English learning, at "Instituto Médio Politécnico do Namibe", and by showing that the large class scenario at IMP-Namibe may be attributed to various factors of which the most pertinent is the imbalance between the…

  5. Time Course of Pupil Center Location after Ocular Drug Application.

    Science.gov (United States)

    Hoang, Tony A; Macdonnell, Jacqueline E; Mangan, Michelle C; Monsour, Cindy S; Polwattage, Buddhika L; Wilson, Sarah F; Suheimat, Marwan; Atchison, David A

    2016-06-01

    To investigate the time course of pupil centration after application of common topical ocular drugs. Single drops of 2.5% phenylephrine hydrochloride, 1% tropicamide, and 2% pilocarpine hydrochloride were applied on different days to the right eyes of 12 participants. Anterior eye images were captured, at 5-min intervals for an hour, using an infrared-sensitive camera. The images were analyzed to determine pupil diameter and pupil center, the latter with respect to the limbal center. As a control, natural pupil size and pupil center were determined under different illuminances. Pupil centers of natural pupils shifted temporally as pupils dilated. At common pupil sizes, drug-induced pupil centers were different from natural pupil centers. Phenylephrine produced a center shift in the nasal and inferior directions that peaked after a mean of 30 min, whereas dilation was continuing up to 60 min. Tropicamide produced transient center shifts in the nasal and inferior directions that peaked at about 10 min before reducing toward baseline values, whereas dilation reached a peak at about 25 min. Pilocarpine produced a small sustained superior shift that, like constriction, reached a peak after about 25 min. Application of topical ophthalmic drugs cause shifts in pupil center that do not match those produced by natural changes in pupil size and that, in the cases of phenylephrine and tropicamide, follow a different time course than the pupil size changes.

  6. Pupil Mimicry Correlates With Trust in In-Group Partners With Dilating Pupils.

    Science.gov (United States)

    Kret, M E; Fischer, A H; De Dreu, C K W

    2015-09-01

    During close interactions with fellow group members, humans look into one another's eyes, follow gaze, and quickly grasp emotion signals. The eye-catching morphology of human eyes, with unique eye whites, draws attention to the middle part, to the pupils, and their autonomic changes, which signal arousal, cognitive load, and interest (including social interest). Here, we examined whether and how these changes in a partner's pupils are processed and how they affect the partner's trustworthiness. Participants played incentivized trust games with virtual partners, whose pupils dilated, remained static, or constricted. Results showed that (a) participants trusted partners with dilating pupils and withheld trust from partners with constricting pupils, (b) participants' pupils mimicked changes in their partners' pupils, and (c) dilation mimicry predicted trust in in-group partners, whereas constriction mimicry did not. We suggest that pupil-contingent trust is in-group bounded and possibly evolved in and because of group life.

  7. Cognitive and Ocular Factors Jointly Determine Pupil Responses under Equiluminance.

    Directory of Open Access Journals (Sweden)

    Tomas Knapen

    Full Text Available Changes in pupil diameter can reflect high-level cognitive signals that depend on central neuromodulatory mechanisms. However, brain mechanisms that adjust pupil size are also exquisitely sensitive to changes in luminance and other events that would be considered a nuisance in cognitive experiments recording pupil size. We implemented a simple auditory experiment involving no changes in visual stimulation. Using finite impulse-response fitting we found pupil responses triggered by different types of events. Among these are pupil responses to auditory events and associated surprise: cognitive effects. However, these cognitive responses were overshadowed by pupil responses associated with blinks and eye movements, both inevitable nuisance factors that lead to changes in effective luminance. Of note, these latter pupil responses were not recording artifacts caused by blinks and eye movements, but endogenous pupil responses that occurred in the wake of these events. Furthermore, we identified slow (tonic changes in pupil size that differentially influenced faster (phasic pupil responses. Fitting all pupil responses using gamma functions, we provide accurate characterisations of cognitive and non-cognitive response shapes, and quantify each response's dependence on tonic pupil size. These results allow us to create a set of recommendations for pupil size analysis in cognitive neuroscience, which we have implemented in freely available software.

  8. Information and Communication Technologies (ICT) and Pupils with Attention Deficit Hyperactivity Disorder (ADHD) Symptoms: Do the Software and the Instruction Method Affect Their Behavior?

    Science.gov (United States)

    Solomonidou, Christina; Garagouni-Areou, Fotina; Zafiropoulou, Maria

    2004-01-01

    The study investigated the effects of Information and Communication Technologies (ICT) use on pupils with Attention Deficit Hyperactivity Disorder (ADHD) symptoms. Nine Greek primary school pupils with ADHD symptoms and four others with no such deficit worked on a computer, either individually or collaboratively, once a week for a six-week period.…

  9. The structure and size of sensory bursts encode stimulus information but only size affects behavior.

    Science.gov (United States)

    Marsat, Gary; Pollack, Gerald S

    2010-04-01

    Cricket ultrasound avoidance is a classic model system for neuroethology. Avoidance steering is triggered by high-firing-rate bursts of spikes in the auditory command neuron AN2. Although bursting is common among sensory neurons, and although the detailed structure of bursts may encode information about the stimulus, it is as yet unclear whether this information is decoded. We address this question in two ways: from an information coding point of view, by showing the relationship between stimulus and burst structure; and also from a functional point of view by showing the relationship between burst structure and behavior. We conclude that the burst structure carries detailed temporal information about the stimulus but that this has little impact on the behavioral response, which is affected mainly by burst size.

  10. Implant Size Availability Affects Reproduction of Distal Femoral Anatomy.

    Science.gov (United States)

    Morris, William Z; Gebhart, Jeremy J; Goldberg, Victor M; Wera, Glenn D

    2016-07-01

    A total knee arthroplasty system offers more distal femoral implant anterior-posterior (AP) sizes than its predecessor. The purpose of this study is to investigate the impact of increased size availability on an implant system's ability to reproduce the AP dimension of the native distal femur. We measured 200 cadaveric femora with the AP-sizing guides of Zimmer (Warsaw, IN) NexGen (8 sizes) and Zimmer Persona (12 sizes) total knee arthroplasty systems. We defined "size deviation" as the difference in the AP dimension between the anatomic size of the native femur and the closest implant size. We defined satisfactory reproduction of distal femoral dimensions as Persona (p Persona. Only 1/200 specimens (0.5%) was a poor fit by Persona, but a satisfactory fit by NexGen (p < 0.001). The novel knee system with 12 versus 8 sizes reproduces the AP dimension of the native distal femur more closely than its predecessor. Further study is needed to determine the clinical impact of these differences.

  11. Does Instructor's Image Size in Video Lectures Affect Learning Outcomes?

    Science.gov (United States)

    Pi, Z.; Hong, J.; Yang, J.

    2017-01-01

    One of the most commonly used forms of video lectures is a combination of an instructor's image and accompanying lecture slides as a picture-in-picture. As the image size of the instructor varies significantly across video lectures, and so do the learning outcomes associated with this technology, the influence of the instructor's image size should…

  12. Challenging the Western Approach to Cultural Comparisons: Young Pupils' Affective Structures Regarding Mathematics in Finland and Chile

    Science.gov (United States)

    Tuohilampi, Laura; Hannula, Markku S.; Varas, Leonor; Giaconi, Valentina; Laine, Anu; Näveri, Liisa; i Nevado, Laia Saló

    2015-01-01

    Large-scale studies measure mathematics-related affect using questionnaires developed by researchers in primarily English-based countries and according to Western-based theories. Influential comparative conclusions about different cultures and countries are drawn based on such measurements. However, there are certain premises involved in these…

  13. Social network size affects neural circuits in macaques.

    Science.gov (United States)

    Sallet, J; Mars, R B; Noonan, M P; Andersson, J L; O'Reilly, J X; Jbabdi, S; Croxson, P L; Jenkinson, M; Miller, K L; Rushworth, M F S

    2011-11-04

    It has been suggested that variation in brain structure correlates with the sizes of individuals' social networks. Whether variation in social network size causes variation in brain structure, however, is unknown. To address this question, we neuroimaged 23 monkeys that had been living in social groups set to different sizes. Subject comparison revealed that living in larger groups caused increases in gray matter in mid-superior temporal sulcus and rostral prefrontal cortex and increased coupling of activity in frontal and temporal cortex. Social network size, therefore, contributes to changes both in brain structure and function. The changes have potential implications for an animal's success in a social context; gray matter differences in similar areas were also correlated with each animal's dominance within its social network.

  14. Pupil responses to task requirement in goal-directed movements

    OpenAIRE

    Jiang, Xianta

    2014-01-01

    Objectively measuring the operators’ task workload in goal-directed motor tasks such as surgical operations, is important for performance and safety. This thesis presents an approach for objectively measuring task workload in goal-directed movements using an important eye response: the pupil diameter. We demonstrate how to capture movement-related pupil size changes during motor tasks, investigate how the pupil responds to task requirement, and show that the pupil diameter can be employed a...

  15. The eye as a window to the listening brain: neural correlates of pupil size as a measure of cognitive listening load.

    Science.gov (United States)

    Zekveld, Adriana A; Heslenfeld, Dirk J; Johnsrude, Ingrid S; Versfeld, Niek J; Kramer, Sophia E

    2014-11-01

    An important aspect of hearing is the degree to which listeners have to deploy effort to understand speech. One promising measure of listening effort is task-evoked pupil dilation. Here, we use functional magnetic resonance imaging (fMRI) to identify the neural correlates of pupil dilation during comprehension of degraded spoken sentences in 17 normal-hearing listeners. Subjects listened to sentences degraded in three different ways: the target female speech was masked by fluctuating noise, by speech from a single male speaker, or the target speech was noise-vocoded. The degree of degradation was individually adapted such that 50% or 84% of the sentences were intelligible. Control conditions included clear speech in quiet, and silent trials. The peak pupil dilation was larger for the 50% compared to the 84% intelligibility condition, and largest for speech masked by the single-talker masker, followed by speech masked by fluctuating noise, and smallest for noise-vocoded speech. Activation in the bilateral superior temporal gyrus (STG) showed the same pattern, with most extensive activation for speech masked by the single-talker masker. Larger peak pupil dilation was associated with more activation in the bilateral STG, bilateral ventral and dorsal anterior cingulate cortex and several frontal brain areas. A subset of the temporal region sensitive to pupil dilation was also sensitive to speech intelligibility and degradation type. These results show that pupil dilation during speech perception in challenging conditions reflects both auditory and cognitive processes that are recruited to cope with degraded speech and the need to segregate target speech from interfering sounds.

  16. Social context effects on pupils' perception of school

    NARCIS (Netherlands)

    Hofman, R.H.; Hofman, W.H.A.; Guldemond, H

    In this study we test the effects of three social contexts of learning on the affective outcomes of schooling, in this case pupils' perception of their primary school. The concept of pupils' school perception is measured using a reliable scale. This scale contains items to measure pupils' perception

  17. How pupils percieve the teacher's motivational techniques?

    Directory of Open Access Journals (Sweden)

    Bodroža Bojana

    2015-01-01

    Full Text Available Current research in the field of education indicates that the behaviour of the teacher affects significantly the quality and level of the pupil's motivation. The aim of our research was to determine the structure of the motivational style of teachers seen from the pupils' perspective, and to find out whether the pupils' perceptions of the teacher's motivational style depend upon cultural-educational influences of the family, and some characteristics of the students (academic achievements, gender. The sample included 856 pupils from 40 elementary schools in Serbia. We used the questionnaire with Likert's scale to obtain the evaluation of the teachers' behaviours. By the factor analysis we extracted three components of the teacher' behaviour: stimulating pupils' interest and competences, de-motivational teachers' behaviours and stimulating freedom of thinking and expression. The results show that the pupils whose parents have lower levels of education think that the behaviour of the teachers is directed to stimulating interest and competencies, as well as freedom of thinking and speech than the pupils of the parents of higher educational status. The control of the influence of the education of parents showed that the pupils of lower academic achievement perceive the teacher's behaviour as de-motivational. Compared to girls boys estimate more highly that teachers stimulate their interests and competencies. A suggestion is offered how a teacher should develop a behavioural style which would positively influence the quality of the pupils' motivation.

  18. Radish (Raphanus sativus) seed size affects germination response to coumarin

    Science.gov (United States)

    The inhibition of seed germination by an allelochemical is generally greater in small seeds than in large seeds. Studies reporting these results used a large number of plant species that varied in seed size, which might have introduced differences in germination characteristics or various parameter...

  19. Olanzapine affects locomotor activity and meal size in male rats

    NARCIS (Netherlands)

    van der Zwaal, Esther M.; Luijendijk, Mieneke C. M.; Evers, Simon S.; la Fleur, Susanne E.; Adan, Roger A. H.

    2010-01-01

    Olanzapine is an antipsychotic drug that frequently induces weight gain accompanied by increased fat deposition as a side effect To investigate how olanzapine affects different aspects of energy balance we used male rats to determine effects on meal patterns food preference locomotor activity and

  20. How does cell size regulation affect population growth?

    CERN Document Server

    Lin, Jie

    2016-01-01

    The proliferation of a growing microbial colony is well characterized by the population growth rate. However, at the single-cell level, isogenic cells often exhibit different cell-cycle durations. For evolutionary dynamics, it is thus important to establish the connection between the population growth rate and the heterogeneous single-cell generation time. Existing theories often make the assumption that the generation times of mother and daughter cells are independent. However, it has been shown that to maintain a bounded cell size distribution, cells that grow exponentially at the single-cell level need to adopt cell size regulation, leading to a negative correlation of mother-daughter generation time. In this work, we construct a general framework to describe the population growth in the presence of size regulation. We derive a formula for the population growth rate, which only depends on the variability of single-cell growth rate, independent of other sources of noises. Our work shows that a population ca...

  1. A mathematical model to predict the size of the pellets formed in freeze pelletization techniques: parameters affecting pellet size.

    Science.gov (United States)

    Cheboyina, Sreekhar; O'Haver, John; Wyandt, Christy M

    2006-01-01

    A mathematical model was developed based on the theory of drop formation to predict the size of the pellets formed in the freeze pelletization process. Further the model was validated by studying the effect of various parameters on the pellet size such as viscosity of the pellet forming and column liquids, surface/interfacial tension, density difference between pellet forming and column liquids; size, shape, and material of construction of the needle tips and temperatures maintained in the columns. In this study, pellets were prepared from different matrices including polyethylene glycols and waxes. The column liquids studied were silicone oils and aqueous glycerol solutions. The surface/interfacial tension, density difference between pellet forming and column liquids and needle tip size were found to be the most important factors affecting pellet size. The viscosity of the column liquid was not found to significantly affect the size of the pellets. The size of the pellets was also not affected by the pellet forming liquids of low viscosities. An increase in the initial column temperature slightly decreased the pellet size. The mathematical model developed was found to successfully predict the size of the pellets with an average error of 3.32% for different matrices that were studied.

  2. Factors affecting coke size and fissuring during cokemaking part 2

    Energy Technology Data Exchange (ETDEWEB)

    Merrick Mahoney; Jeff Keating; Susan Woodhouse [BHP Billiton Newcastle Technology Centre (Australia)

    2007-12-15

    This work addressed the mechanism of fissuring during metallurgical cokemaking and extends on a previous ACARP project. Considerable progress has been made in understanding the mechanism by an integrated modelling work; experimental program. The work points to opportunities for controlling the carbonisation process to achieve required outcomes in terms of coke lump size and distribution. Key outcomes of the work included: A methodology for determination of the minimum spacing between fissures, and the time at which period doublings (i.e. every second fissure stopping) occur, has been developed and implemented. Implementation of the methodology allows the determination of the complete fissure pattern (at least those perpendicular to the oven walls) for a given coke oven/charge configuration. A plausible mechanistic explanation of the formation of lateral fissures (those that are parallel to the oven walls) has been developed. Knowledge of the fissure pattern, combined with the lateral fissuring explanation, enables the determination of typical size and shape of lumps after stabilisation of the coke.

  3. Detection of Changes in Surgical Difficulty: Evidence From Pupil Responses.

    Science.gov (United States)

    Zheng, Bin; Jiang, Xianta; Atkins, M Stella

    2015-12-01

    Assessing the workload of surgeons requires technology to continuously monitor surgeons' behaviors without interfering with their performance. We investigated the feasibility of using eye-tracking to reveal surgeons' response to increasing task difficulty. A controlled study was conducted in a simulated operating room, where 14 subjects were required to perform a laparoscopic procedure that includes 9 subtasks. The subtasks could be divided into 3 types with different levels of task difficulty, calculated by the index of task difficulty (ID) proposed by Fitts in 1954. Pupillary responses of subjects in performing the procedure were recorded using Tobii eye-tracking equipment. Peak pupil dilation and movement time were compared between subtasks with different IDs as well as between fast moving and slow aiming phases within each subtask. When the task difficulty was increased, task completion time increased. Meanwhile, the subjects' peak pupil size also increased. As the entire procedure was performed continuously, we found that pupil responses were not only affected by the ID in the current subtask but also influenced by subtasks before and after. Decomposing a surgical procedure into meaningful subtasks and examining the surgeon's pupil response to each subtask enables us to identify the challenging steps within a continuous surgical procedure. Psychomotor evidence on surgeon's performance may lead to an innovation for designing a task-specific training curriculum. © The Author(s) 2015.

  4. How does poaching affect the size of national parks?

    Science.gov (United States)

    Dobson, Andy; Lynes, Laura

    2008-04-01

    A variety of human activities have detrimental impacts on populations of species the park is designed to protect. These impacts range from direct hunting for trophy or subsistence needs, through vehicular collisions, to the direct loss of habitat due to forestry and agricultural activity. These impacts reduce the effective size of the parks and require changes in management policy that deal both with the direct cause of the problem and the underlying social conflicts that the presence of parks can place on humans in the surrounding communities. Recent studies from the Serengeti illustrate that increases in anti-poaching patrols increase the risk of poacher detection and lead to dramatic declines in levels of poaching. The economic arguments that support investment in anti-poaching patrols, rather than increased sentences for poachers who are caught, can be generalized to examine the costs and benefits of other changes in natural resource management that arise when attempting to manage the impact of anthropogenic activities in and around national parks.

  5. Modulation of stimulus contrast on the human pupil orienting response.

    Science.gov (United States)

    Wang, Chin-An; Munoz, Douglas P

    2014-09-01

    The sudden appearance of a novel stimulus initiates a series of responses to orient the body for appropriate actions, including not only shifts of gaze and attention, but also transient pupil dilation. Modulation of pupil dynamics by stimulus properties is less understood, although its effects on other components of orienting have been extensively explored. Microstimulation of the superior colliculus evoked transient pupil dilation, and the initial component of pupil dilation evoked by microstimulation was similar to that elicited by the presentation of salient sensory stimuli, suggesting a coordinated role of the superior colliculus on this behavior, although evidence in humans is yet to be established. To examine pupil orienting responses in humans, we presented visual stimuli while participants fixated on a central visual spot. Transient pupil dilation in humans was elicited after presentation of a visual stimulus in the periphery. The evoked pupil responses were modulated systematically by stimulus contrast, with faster and larger pupil responses triggered by higher contrast stimuli. The pupil response onset latencies for high contrast stimuli were similar to those produced by the light reflex and significantly faster than the darkness reflex, suggesting that the initial component of pupil dilation is probably mediated by inhibition of the parasympathetic pathway. The contrast modulation was pronounced under different levels of baseline pupil size. Together, our results demonstrate visual contrast modulation on the orienting pupil response in humans.

  6. The Pupil Premium: Next Steps

    Science.gov (United States)

    Sutton Trust, 2015

    2015-01-01

    The pupil premium was introduced by the Coalition government in April 2011 to provide additional funding for disadvantaged pupils. The main difference between the premium and previous funding for disadvantaged pupils is that the premium is linked to individual pupils. On July 1, 2015, The Pupil Premium Summit organized by the Education Endowment…

  7. Transient pupil response is modulated by contrast-based saliency.

    Science.gov (United States)

    Wang, Chin-An; Boehnke, Susan E; Itti, Laurent; Munoz, Douglas P

    2014-01-08

    The sudden appearance of a novel stimulus in the environment initiates a series of orienting responses that include coordinated shifts of gaze and attention, and also transient changes in pupil size. Although numerous studies have identified a significant effect of stimulus saliency on shifts of gaze and attention, saliency effects on pupil size are less understood. To examine salience-evoked pupil responses, we presented visual, auditory, or audiovisual stimuli while monkeys fixated a central visual spot. Transient pupil dilation was elicited after visual stimulus presentation regardless of target luminance relative to background, and auditory stimuli also evoked similar pupil responses. Importantly, the evoked pupil response was modulated by contrast-based saliency, with faster and larger pupil responses following the presentation of more salient stimuli. The initial transient component of pupil dilation was qualitatively similar to that evoked by weak microstimulation of the midbrain superior colliculus. The pupil responses elicited by audiovisual stimuli were well predicted by a linear summation of each modality response. Together, the results suggest that the transient pupil response, as one component of orienting, is modulated by contrast-based saliency, and the superior colliculus is likely involved in its coordination.

  8. Brain size affects female but not male survival under predation threat.

    Science.gov (United States)

    Kotrschal, Alexander; Buechel, Séverine D; Zala, Sarah M; Corral-Lopez, Alberto; Penn, Dustin J; Kolm, Niclas

    2015-07-01

    There is remarkable diversity in brain size among vertebrates, but surprisingly little is known about how ecological species interactions impact the evolution of brain size. Using guppies, artificially selected for large and small brains, we determined how brain size affects survival under predation threat in a naturalistic environment. We cohoused mixed groups of small- and large-brained individuals in six semi-natural streams with their natural predator, the pike cichlid, and monitored survival in weekly censuses over 5 months. We found that large-brained females had 13.5% higher survival compared to small-brained females, whereas the brain size had no discernible effect on male survival. We suggest that large-brained females have a cognitive advantage that allows them to better evade predation, whereas large-brained males are more colourful, which may counteract any potential benefits of brain size. Our study provides the first experimental evidence that trophic interactions can affect the evolution of brain size.

  9. Assessing Pupils' Progress

    Science.gov (United States)

    Ollerton, Mike

    2010-01-01

    In this article, the author explores what Assessing Pupils' Progress (APP) is about. He contends that the predilection for testing is a catastrophe as far as the teaching and learning of mathematics is concerned; it is an outcome of the drive for collecting so-called "data" on pupils. What those people, who should know better, either choose to…

  10. Creating Pupils' Internet Magazine

    Science.gov (United States)

    Bognar, Branko; Šimic, Vesna

    2014-01-01

    This article presents an action research, which aimed to improve pupils' literary creativity and enable them to use computers connected to the internet. The study was conducted in a small district village school in Croatia. Creating a pupils' internet magazine appeared to be an excellent way for achieving the educational aims of almost all…

  11. Accommodation and pupil responses to random-dot stereograms.

    Science.gov (United States)

    Suryakumar, Rajaraman; Allison, Robert

    2016-01-01

    We investigated the dynamics of accommodative and pupillary responses to random-dot stereograms presented in crossed and uncrossed disparity in six visually normal young adult subjects (mean age=25.8±3.1 years). Accommodation and pupil measures were monitored monocularly with a custom built photorefraction system while subjects fixated at the center of a random-dot stereogram. On each trial, the stereogram initially depicted a flat plane and then changed to depict a sinusoidal corrugation in depth while fixation remained constant. Increase in disparity specified depth resulted in pupil constriction during both crossed and uncrossed disparity presentations. The change in pupil size between crossed and uncrossed disparity conditions was not significantly different (p>0.05). The change in pupil size was also accompanied by a small concomitant increase in accommodation. In addition, the dynamic properties of pupil responses varied as a function of their initial (starting) diameter. The finding that accommodation and pupil responses increased with disparity regardless of the sign of retinal disparity suggests that these responses were driven by apparent depth rather than shifts in mean simulated distance of the stimulus. Presumably the need for the increased depth of focus when viewing stimuli extended in depth results in pupil constriction which also results in a concomitant change in accommodation. Starting position effects in pupil response confirm the non-linearity in the operating range of the pupil.

  12. Cognitive and Ocular Factors Jointly Determine Pupil Responses under Equiluminance

    NARCIS (Netherlands)

    Knapen, T.; de Gee, J.W.; Brascamp, J.; Nuiten, S.; Hoppenbrouwers, S.; Theeuwes, J.

    2016-01-01

    Changes in pupil diameter can reflect high-level cognitive signals that depend on central neuromodulatory mechanisms. However, brain mechanisms that adjust pupil size are also exquisitely sensitive to changes in luminance and other events that would be considered a nuisance in cognitive experiments

  13. Pupils' Understanding of Air Pollution

    Science.gov (United States)

    Dimitriou, Anastasia; Christidou, Vasilia

    2007-01-01

    This paper reports on a study of pupils' knowledge and understanding of atmospheric pollution. Specifically, the study is aimed at identifying: 1) the extent to which pupils conceptualise the term "air pollution" in a scientifically appropriate way; 2) pupils' knowledge of air pollution sources and air pollutants; and 3) pupils' knowledge of air…

  14. 屈光手术前个体眼高阶像差与中间视觉状态下瞳孔大小%Ocular higher-order aberrations and mesopic pupil size in individuals screened for refractive surgery

    Institute of Scientific and Technical Information of China (English)

    Seyed Javad Hashemian; Mohammad Soleimani; Alireza Foroutan; Mahmood Joshaghani; Mohammad Jafar Ghaempanah; Mohammad Ebrahim Jafari; Mehdi Yaseri

    2012-01-01

    目的:研究眼高阶像差的分布(HOAs)和mesopic瞳孔的大小在个体中筛选的屈光手术.方法:我们采用Zywave像差分析仪(博士伦)分别对患有近视、近视散光和复性近视散光患者1 240例2 458眼和患有远视、远视散光和复性远视散光患者110例215眼的高阶像差和瞳孔大小进行检测.所有患者屈光不正均可矫正,无屈光手术史或潜在疾病.HOAs的均方根值、总球面像差、总斜射球面像差和中间视觉状态下瞳孔的大小进行了分析,眼高阶像差测量均在瞳孔≥6.0mm,且瞳孔大小的测量均为在中间视觉状态下进行.结果:HOAs均方根值、总球面像差和总斜射球面像差在近视眼组与远视眼组分别为0.369±0.233μm、0.133±0.112μm、0.330±0.188μm;0.418±0.214μm、0.202±0.209μm、0.343±0.201μm.与近视患者相比,远视患者的总HOAs和总球面像差更大(P均<0.01).年龄匹配分析显示在远视眼组只有总球面像差较高(P=0.05).近视眼组的中间视觉状态下瞳孔大小较大(P≤0.05).结论:实验结果表明两组的HOAs的水平有显著差异,这对于将行屈光手术的伊朗人很重要.远视眼组的总球面像差显著高于近视眼组,中间视觉状态下瞳孔大小在近视眼组较大.%AIM: To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery.patients with myopia, myopic astigmatism and compound myopic astigmatism and 215 eyes of 110 patients with hyperopia, hyperopic astigmatism and compound hyperopic astigmatism using the Zywave aberrometer (Busch& Lomb). All patients had correctable refractive errors without a history of refractive surgery or underlying diseases. Root-mean-square values of HOAs, total spherical aberration, total coma and mesopic pupil size were analyzed. Ocular HOAs were measured across a ≥6.0mm pupil, and pupil size measurements were performed under the mesopic condition. the

  15. Nano-sized polystyrene affects feeding, behavior and physiology of brine shrimp Artemia franciscana larvae

    NARCIS (Netherlands)

    Bergami, Elisa; Bocci, Elena; Vannuccini, Maria Luisa; Monopoli, Marco; Salvati, Anna; Dawson, Kenneth A; Corsi, Ilaria

    2016-01-01

    Nano-sized polymers as polystyrene (PS) constitute one of the main challenges for marine ecosystems, since they can distribute along the whole water column affecting planktonic species and consequently disrupting the energy flow of marine ecosystems. Nowadays very little knowledge is available on th

  16. Nano-sized polystyrene affects feeding, behavior and physiology of brine shrimp Artemia franciscana larvae

    NARCIS (Netherlands)

    Bergami, Elisa; Bocci, Elena; Vannuccini, Maria Luisa; Monopoli, Marco; Salvati, Anna; Dawson, Kenneth A; Corsi, Ilaria

    Nano-sized polymers as polystyrene (PS) constitute one of the main challenges for marine ecosystems, since they can distribute along the whole water column affecting planktonic species and consequently disrupting the energy flow of marine ecosystems. Nowadays very little knowledge is available on

  17. Optimal pupil apodizations for arbitrary apertures

    CERN Document Server

    Carlotti, A; Kasdin, N J

    2011-01-01

    We present here fully optimized two-dimensional pupil apodizations for which no specific geometric constraints are put on the pupil plane apodization, apart from the shape of the aperture itself. Masks for circular and segmented apertures are displayed, with and without central obstruction and spiders. Examples of optimal masks are shown for Subaru, SPICA and JWST. Several high-contrast regions are considered with different sizes, positions, shapes and contrasts. It is interesting to note that all the masks that result from these optimizations tend to have a binary transmission profile.

  18. Pupil-linked arousal determines variability in perceptual decision making

    National Research Council Canada - National Science Library

    Murphy, Peter R; Vandekerckhove, Joachim; Nieuwenhuis, Sander

    2014-01-01

    .... We measured pupil size, a highly sensitive index of arousal, while human subjects performed a motion-discrimination task, and decomposed task behavior into latent decision making parameters using...

  19. Pupil-mimicry conditions trust in partners: moderation by oxytocin and group membership.

    Science.gov (United States)

    Kret, Mariska E; De Dreu, Carsten K W

    2017-03-15

    Across species, oxytocin, an evolutionarily ancient neuropeptide, facilitates social communication by attuning individuals to conspecifics' social signals, fostering trust and bonding. The eyes have an important signalling function; and humans use their salient and communicative eyes to intentionally and unintentionally send social signals to others, by contracting the muscles around their eyes and pupils. In our earlier research, we observed that interaction partners with dilating pupils are trusted more than partners with constricting pupils. But over and beyond this effect, we found that the pupil sizes of partners synchronize and that when pupils synchronously dilate, trust is further boosted. Critically, this linkage between mimicry and trust was bound to interactions between ingroup members. The current study investigates whether these findings are modulated by oxytocin and sex of participant and partner. Using incentivized trust games with partners from ingroup and outgroup whose pupils dilated, remained static or constricted, this study replicates our earlier findings. It further reveals that (i) male participants withhold trust from partners with constricting pupils and extend trust to partners with dilating pupils, especially when given oxytocin rather than placebo; (ii) female participants trust partners with dilating pupils most, but this effect is blunted under oxytocin; (iii) under oxytocin rather than placebo, pupil dilation mimicry is weaker and pupil constriction mimicry stronger; and (iv) the link between pupil constriction mimicry and distrust observed under placebo disappears under oxytocin. We suggest that pupil-contingent trust is parochial and evolved in social species in and because of group life.

  20. Class composition influences on pupils' cognitive development

    NARCIS (Netherlands)

    Peetsma, T.; van der Veen, I.; Koopman, P.; van Schooten, E.

    2006-01-01

    The proportion of low-achieving children in a class can affect the progress of individual pupils in that class. Having a large proportion of low achievers in a class could slow down growth in cognitive achievement but, might also boost such growth, due to the effects of specialist teaching geared to

  1. Class composition influences on pupils' cognitive development

    NARCIS (Netherlands)

    Peetsma, T.; van der Veen, I.; Koopman, P.; van Schooten, E.

    2006-01-01

    The proportion of low-achieving children in a class can affect the progress of individual pupils in that class. Having a large proportion of low achievers in a class could slow down growth in cognitive achievement but, might also boost such growth, due to the effects of specialist teaching geared to

  2. How Finland Serves Gifted and Talented Pupils

    Science.gov (United States)

    Tirri, Kirsi; Kuusisto, Elina

    2013-01-01

    The purpose of this article is to provide an overview of the ways gifted and talented pupils are served in Finland. The trend toward individualism and freedom of choice as well as national policy affecting gifted education are discussed. Empirical research on Finnish teachers' attitudes toward gifted education with respect to the national…

  3. Foraging arena size and structural complexity affect the dynamics of food distribution in ant colonies.

    Science.gov (United States)

    Buczkowski, Grzegorz; VanWeelden, Matthew

    2010-12-01

    Food acquisition by ant colonies is a complex process that starts with acquiring food at the source (i.e., foraging) and culminates with food exchange in or around the nest (i.e., feeding). While ant foraging behavior is relatively well understood, the process of food distribution has received little attention, largely because of the lack of methodology that allows for accurate monitoring of food flow. In this study, we used the odorous house ant, Tapinoma sessile (Say) to investigate the effect of foraging arena size and structural complexity on the rate and the extent of spread of liquid carbohydrate food (sucrose solution) throughout a colony. To track the movement of food, we used protein marking and double-antibody sandwich enzyme-linked immunosorbent assay, DAS-ELISA. Variation in arena size, in conjunction with different colony sizes, allowed us to test the effect of different worker densities on food distribution. Results demonstrate that both arena size and colony size have a significant effect on the spread of the food and the number of workers receiving food decreased as arena size and colony size increased. When colony size was kept constant and arena size increased, the percentage of workers testing positive for the marker decreased, most likely because of fewer trophallactic interactions resulting from lower worker density. When arena size was kept constant and colony size increased, the percentage of workers testing positive decreased. Nonrandom (clustered) worker dispersion and a limited supply of food may have contributed to this result. Overall, results suggest that food distribution is more complete is smaller colonies regardless of the size of the foraging arena and that colony size, rather than worker density, is the primary factor affecting food distribution. The structural complexity of foraging arenas ranged from simple, two-dimensional space (empty arenas) to complex, three-dimensional space (arenas filled with mulch). The structural

  4. Pupil diameter reflects uncertainty in attentional selection during visual search

    Directory of Open Access Journals (Sweden)

    Joy J. Geng

    2015-08-01

    Full Text Available Pupil diameter has long been used as a metric of cognitive processing. However, recent advances suggest that the cognitive sources of change in pupil size may reflect LC-NE function and the calculation of unexpected uncertainty in decision processes (Aston-Jones & Cohen, 2005b; Yu & Dayan, 2005. In the current experiments, we explored the role of uncertainty in attentional selection on task-evoked changes in pupil diameter during visual search. We found that task-evoked changes in pupil diameter were related to uncertainty during attentional selection as measured by reaction time and performance accuracy (Experiments 1-2. Control analyses demonstrated that the results are unlikely to be due to error monitoring or response uncertainty. Our results suggest that pupil diameter can be used as an implicit metric of uncertainty in ongoing attentional selection requiring effortful control processes.

  5. High School Pupils' Understanding of Peer Counselling and Willingness to Use it for Different Types of Bullying

    Science.gov (United States)

    Boulton, Michael John

    2014-01-01

    Bullying affects a substantial proportion of school pupils, and peer counselling services have been established to help tackle this problem. The present study aimed to further the understanding of why affected pupils do or do not choose to utilise this form of social support. Pupils ("N" = 99, aged 12-16 years) from the UK were asked…

  6. [Pupil and melanopsin photoreception].

    Science.gov (United States)

    Ishikawa, Hitoshi

    2013-03-01

    The iris is the most anterior portion of the uveal tract. The pupil is round opening near the center of the iris; it is displaced slightly downward and nasally with respect to the center of the cornea. The mammalian iris sphincter is considered to be innervated by cholinergic, and the dilator muscle by adrenergic excitatory nerve fibers, and both miosis and mydriasis are the result of contraction of the iris sphincter and the dilator muscles due to activation of these excitatory nerve fibers. Pharmacological and histological investigations also reveal that the sphincter muscle is innervated in part by inhibitory adrenergic nerve fibers, and that the dilator muscle is also innervated by inhibitory cholinergic nerve fibers. In addition to the release of acetylcholine and norepinephrine by these nerves, the peripheral nerves to the mammalian iris contain various neuropeptides, although the functional role of these pepetides is not clear. It has been known for more than 100 years that two types of photosensitive cells exist in man. However, some totally blind individuals maintain a normal circadian rhythm. Such a phenomenon cannot be explained by the rod and cone functions. Recently, a new photosensitive pigment, melanopsin, was found in the dermal melanophore cells of the frog. In 2002, melanopsin-containing retinal ganglion cells (mRGCs) were discovered and revealed that mRGCs would depolarize without input from the photoreceptors, meaning that these cells are photosensitive. In the human retina, mRGCs comprise only 0.2% of all ganglion cells. Electrophysiological studies show that light slowly depolarizes mRGCs but rapidly hyperpolarizes rods and cones. The mRGCs innervate the suprachiasmatic nucleus, which is the master circadian pacemaker in mammals, and the olivary pretectal nucleus of the midbrain. In addition to their role in circadian entrainment, the mRGCs mediate the pupillary light reflex. We investigated the mechanism of photoreception by retinal

  7. Separability Filter for Localizing Abnormal Pupil: Identification Criteria of Input Image

    Directory of Open Access Journals (Sweden)

    Tutik Ida Rosanti

    2013-11-01

    Full Text Available Separability filter method is a reliable method for pupil detection. However, so far this method is implemented for detecting pupil of normal eye, while for abnormal eye such as cataract and glaucoma patients; they have different characteristics of pupil such as color, shape and radius size of pupil. In this paper we propose to use separability filter for detecting pupil of abnormal patients with different characteristics. We faced a problem about radius size, shape and color of pupil; therefore we implemented Hough Transform, Blob area and Brightness for identifying input images before applying separability filter. The experiment results show that we can increase performance of pupil detection for abnormal eye to be 95.65%.

  8. Cigarette access and pupil smoking rates: a circular relationship?

    Science.gov (United States)

    Turner, Katrina M; Gordon, Jacki; Young, Robert

    2004-12-01

    Adolescents obtain cigarettes from both commercial and social sources. While the relationship between commercial access and adolescent smoking has been researched, no one has considered in detail whether rates of peer smoking affect cigarette availability. In two relatively deprived Scottish schools that differed in their pupil smoking rates, we assess pupil access to cigarettes. 896 13 and 15 year olds were surveyed, and 25 single-sex discussion groups held with a sub-sample of the 13 year olds. Smokers in both schools obtained cigarettes from shops, food vans and other pupils. However, pupils in the 'high' smoking school perceived greater access to both commercial and social sources, and had access to an active 'peer market'. These findings suggest that variations in cigarette access may contribute to school differences in pupil smoking rates, and that the relationship between access and adolescent smoking is circular, with greater availability increasing rates, and higher rates enhancing access.

  9. Particle size distribution of rice flour affecting the starch enzymatic hydrolysis and hydration properties.

    Science.gov (United States)

    de la Hera, Esther; Gomez, Manuel; Rosell, Cristina M

    2013-10-15

    Rice flour is becoming very attractive as raw material, but there is lack of information about the influence of particle size on its functional properties and starch digestibility. This study evaluates the degree of dependence of the rice flour functional properties, mainly derived from starch behavior, with the particle size distribution. Hydration properties of flours and gels and starch enzymatic hydrolysis of individual fractions were assessed. Particle size heterogeneity on rice flour significantly affected functional properties and starch features, at room temperature and also after gelatinization; and the extent of that effect was grain type dependent. Particle size heterogeneity on rice flour induces different pattern in starch enzymatic hydrolysis, with the long grain having slower hydrolysis as indicated the rate constant (k). No correlation between starch digestibility and hydration properties or the protein content was observed. It seems that in intact granules interactions with other grain components must be taken into account. Overall, particle size fractionation of rice flour might be advisable for selecting specific physico-chemical properties.

  10. Infant pupil diameter changes in response to others' positive and negative emotions.

    Directory of Open Access Journals (Sweden)

    Elena Geangu

    Full Text Available It has been suggested that infants resonate emotionally to others' positive and negative affect displays, and that these responses become stronger towards emotions with negative valence around the age of 12-months. In this study we measured 6- and 12-month-old infants' changes in pupil diameter when presented with the image and sound of peers experiencing happiness, distress and an emotionally neutral state. For all participants the perception of another's distress triggered larger pupil diameters. Perceiving other's happiness also induced larger pupil diameters but for shorter time intervals. Importantly, we also found evidence for an asymmetry in autonomous arousal towards positive versus negative emotional displays. Larger pupil sizes for another's distress compared to another's happiness were recorded shortly after stimulus onset for the older infants, and in a later time window for the 6-month-olds. These findings suggest that arousal responses for negative as well as for positive emotions are present in the second half of the first postnatal year. Importantly, an asymmetry with stronger responses for negative emotions seems to be already present at this age.

  11. Cryogenic Pupil Alignment Test Architecture for Aberrated Pupil Images

    Science.gov (United States)

    Bos, Brent; Kubalak, David A.; Antonille, Scott; Ohl, Raymond; Hagopian, John G.

    2009-01-01

    A document describes cryogenic test architecture for the James Webb Space Telescope (JWST) integrated science instrument module (ISIM). The ISIM element primarily consists of a mechanical metering structure, three science instruments, and a fine guidance sensor. One of the critical optomechanical alignments is the co-registration of the optical telescope element (OTE) exit pupil with the entrance pupils of the ISIM instruments. The test architecture has been developed to verify that the ISIM element will be properly aligned with the nominal OTE exit pupil when the two elements come together. The architecture measures three of the most critical pupil degrees-of-freedom during optical testing of the ISIM element. The pupil measurement scheme makes use of specularly reflective pupil alignment references located inside the JWST instruments, ground support equipment that contains a pupil imaging module, an OTE simulator, and pupil viewing channels in two of the JWST flight instruments. Pupil alignment references (PARs) are introduced into the instrument, and their reflections are checked using the instrument's mirrors. After the pupil imaging module (PIM) captures a reflected PAR image, the image will be analyzed to determine the relative alignment offset. The instrument pupil alignment preferences are specularly reflective mirrors with non-reflective fiducials, which makes the test architecture feasible. The instrument channels have fairly large fields of view, allowing PAR tip/tilt tolerances on the order of 0.5deg.

  12. Dynamic exit pupil trackers for autostereoscopic displays.

    Science.gov (United States)

    Akşit, Kaan; Baghsiahi, Hadi; Surman, Phil; Ölçer, Selim; Willman, Eero; Selviah, David R; Day, Sally; Urey, Hakan

    2013-06-17

    This paper describes the first demonstrations of two dynamic exit pupil (DEP) tracker techniques for autostereoscopic displays. The first DEP tracker forms an exit pupil pair for a single viewer in a defined space with low intraocular crosstalk using a pair of moving shutter glasses located within the optical system. A display prototype using the first DEP tracker is constructed from a pair of laser projectors, pupil-forming optics, moving shutter glasses at an intermediate pupil plane, an image relay lens, and a Gabor superlens based viewing screen. The left and right eye images are presented time-sequentially to a single viewer and seen as a 3D image without wearing glasses and allows the viewer to move within a region of 40 cm × 20 cm in the lateral plane, and 30 cm along the axial axis. The second DEP optics can move the exit pupil location dynamically in a much larger 3D space by using a custom spatial light modulator (SLM) forming an array of shutters. Simultaneous control of multiple exit pupils in both lateral and axial axes is demonstrated for the first time and provides a viewing volume with an axial extent of 0.6-3 m from the screen and within a lateral viewing angle of ± 20° for multiple viewers. This system has acceptable crosstalk (< 5%) between the stereo image pairs. In this novel version of the display the optical system is used as an advanced dynamic backlight for a liquid crystal display (LCD). This has advantages in terms of overall display size as there is no requirement for an intermediate image, and in image quality. This system has acceptable crosstalk (< 5%) between the stereo image pairs.

  13. Effects of Pupil Diameter on Light Detection and Temporal Modulation

    Institute of Scientific and Technical Information of China (English)

    Rachel S Li; Andrew W Siu; Johnny C Liyu; Elice C Chan

    2003-01-01

    Purpose: This study compared the effects of pupil variation on light detection and temporal modulation across the central visual field.Methods:Light detection sensitivity (LDS) and low flickering frequency (6Hz) temporal modulation sensitivity (TMS) of 20 young subjects were measured from the central visual field of the right eyes using an automated perimeter (Medmont M600). The measurements were taken under 3 artificial pupils, I.e. 3 mm, 4.3 mm and 6 mm diameters.The sensitivities were grouped and averaged for different retinal eccentricities(3°, 6°, 10° and 15°).Results:TMS and LDS were reduced with increasing retinal eccentricities( P < 0.001)and decreasing pupil diameters( P < 0.001). TMS collected from all pupil diameters were significantly different from each other( P < 0.001). Similarly, LDS under 3 mm pupil was statistically different from those of 4.3 mm and 6 mm(P < 0.003). Comparison of the hills of vision showed that pupil variation resulted in significantly different slopes (P=0.001).The slopes were also found to be significantly different between TMS and LDS (P=0.012).Conclusions: The data showed that dilated pupil resulted in significantly higher sensitivities than those of smaller pupil for both visual functions. The difference in the slopes of hills of vision also suggested that the variation in retinal illumination affected the visual responses differently at various retinal eccentricitities for TMS and LDS.

  14. [Development of sociopsychological adaptation of schoolchildren and vocational school pupils].

    Science.gov (United States)

    Goncharov, G A; Nadezhdin, D S

    2009-01-01

    The purpose of this study was to comparatively analyze the influence of family factors on social and psychological adaptation and achievement motivation in pupils from general education schools and in their coevals from vocational educational schools (VES). An experimental study was conducted in 10th-form pupils from a number of Moscow schools and persons of the same age who were one-year course pupils from a Moscow VES. A total of 242 pupils, including 130 schoolchildren and 112 one-year course pupils from the VES, were examined. The social and psychological adaptation questionnaire developed by K. Rodgers and R. Diamond was used to estimate achievement motivation by the Mehrabian test. The performed study confirmed the negative impact of poor family relations on pupils' sociological and psychological adaptation independently of the type of a general educational establishment. The high maternal educational level had a good effect on the adaptability of schoolchildren, that of boys in particular, whereas the paternal educational status is of the same value to VES pupils. Family relations and maternal and paternal education levels significantly affect the formation of achievement motive in pupils and their social and psychological adaptation as a whole.

  15. Relationships for Learning: Using Pupil Voice to Define Teacher-Pupil Relationships that Enhance Pupil Engagement

    Science.gov (United States)

    Marsh, Helena

    2012-01-01

    This paper is a summary of a pupil voice research project conducted to investigate the influence that teacher-pupil relationships have on pupils' feelings of engagement with their school. The study involved two year groups (12-13 and 14-15 year olds) in a rural secondary school in Cambridgeshire. Data sources were collected through a questionnaire…

  16. The impact of affect on willingness-to-pay and desired-set-size.

    Science.gov (United States)

    Hafenbrädl, Sebastian; Hoffrage, Ulrich; White, Chris M

    2013-01-01

    What role does affect play in economic decision making? Previous research showed that the number of items had a linear effect on the willingness-to-pay for those items when participants were computationally primed, whereas participants' willingness-to-pay was insensitive to the amount when they were affectively primed. We extend this research by also studying the impact of affect on nonmonetary costs of waiting for items to be displayed and of screening them in a computer task. We assessed these costs by asking participants how many items they desired to see before making their selection. In our experiment, the effect of priming on desired-set-size was even larger than on willingness-to-pay, which can be explained by the fact that the nonmonetary costs, waiting time, were real, whereas willingness-to-pay was hypothetical. Participants also reported their satisfaction with the choosing process and the chosen items; no linear or nonlinear relationship was found between the self-determined desired-set-size and satisfaction.

  17. Prognostic Factors Affecting Rotator Cuff Healing After Arthroscopic Repair in Small to Medium-sized Tears.

    Science.gov (United States)

    Park, Ji Soon; Park, Hyung Jun; Kim, Sae Hoon; Oh, Joo Han

    2015-10-01

    Small and medium-sized rotator cuff tears usually have good clinical and anatomic outcomes. However, healing failure still occurs in some cases. To evaluate prognostic factors for rotator cuff healing in patients with only small to medium-sized rotator cuff tears. Case-control study; Level of evidence, 3. Data were prospectively collected from 339 patients with small to medium-sized rotator cuff tears who underwent arthroscopic repair by a single surgeon between March 2004 and August 2012 and who underwent magnetic resonance imaging or computed tomographic arthrography at least 1 year after surgery. The mean age of the patients was 59.8 years (range, 39-80 years), and the mean follow-up time was 20.8 months (range, 12-66 months). The functional evaluation included the visual analog scale (VAS) for pain, American Shoulder and Elbow Surgeons score, Constant-Murley score, and Simple Shoulder Test. Postoperative VAS for pain and functional scores improved significantly compared with preoperative values (P infraspinatus muscle, tear size (anteroposterior dimension), and age were significant factors affecting rotator cuff healing (P infraspinatus fatty degeneration correlated with a higher failure rate. The failure rate was also significantly higher in patients with a tear >2 cm in size (34.2%) compared with patients with a tear ≤2 cm (10.6%) (P infraspinatus muscle according to the Goutallier classification could be a reference point for successful healing, and anatomic outcomes might be better if repair is performed before the patient is 69 years old and the tear size exceeds 2 cm. © 2015 The Author(s).

  18. Factors affecting ground-water exchange and catchment size for Florida lakes in mantled karst terrain

    Science.gov (United States)

    Lee, Terrie Mackin

    2002-01-01

    In the mantled karst terrain of Florida, the size of the catchment delivering ground-water inflow to lakes is often considerably smaller than the topographically defined drainage basin. The size is determined by a balance of factors that act individually to enhance or diminish the hydraulic connection between the lake and the adjacent surficial aquifer, as well as the hydraulic connection between the surficial aquifer and the deeper limestone aquifer. Factors affecting ground-water exchange and the size of the ground-water catchment for lakes in mantled karst terrain were examined by: (1) reviewing the physical and hydrogeological characteristics of 14 Florida lake basins with available ground-water inflow estimates, and (2) simulating ground-water flow in hypothetical lake basins. Variably-saturated flow modeling was used to simulate a range of physical and hydrogeologic factors observed at the 14 lake basins. These factors included: recharge rate to the surficial aquifer, thickness of the unsaturated zone, size of the topographically defined basin, depth of the lake, thickness of the surficial aquifer, hydraulic conductivity of the geologic units, the location and size of karst subsidence features beneath and onshore of the lake, and the head in the Upper Floridan aquifer. Catchment size and the magnitude of ground-water inflow increased with increases in recharge rate to the surficial aquifer, the size of the topographically defined basin, hydraulic conductivity in the surficial aquifer, the degree of confinement of the deeper Upper Floridan aquifer, and the head in the Upper Floridan aquifer. The catchment size and magnitude of ground-water inflow increased with decreases in the number and size of karst subsidence features in the basin, and the thickness of the unsaturated zone near the lake. Model results, although qualitative, provided insights into: (1) the types of lake basins in mantled karst terrain that have the potential to generate small and large

  19. Female brain size affects the assessment of male attractiveness during mate choice

    Science.gov (United States)

    Corral-López, Alberto; Bloch, Natasha I.; Kotrschal, Alexander; van der Bijl, Wouter; Buechel, Severine D.; Mank, Judith E.; Kolm, Niclas

    2017-01-01

    Mate choice decisions are central in sexual selection theory aimed to understand how sexual traits evolve and their role in evolutionary diversification. We test the hypothesis that brain size and cognitive ability are important for accurate assessment of partner quality and that variation in brain size and cognitive ability underlies variation in mate choice. We compared sexual preference in guppy female lines selected for divergence in relative brain size, which we have previously shown to have substantial differences in cognitive ability. In a dichotomous choice test, large-brained and wild-type females showed strong preference for males with color traits that predict attractiveness in this species. In contrast, small-brained females showed no preference for males with these traits. In-depth analysis of optomotor response to color cues and gene expression of key opsins in the eye revealed that the observed differences were not due to differences in visual perception of color, indicating that differences in the ability to process indicators of attractiveness are responsible. We thus provide the first experimental support that individual variation in brain size affects mate choice decisions and conclude that differences in cognitive ability may be an important underlying mechanism behind variation in female mate choice. PMID:28345039

  20. Brain size affects the behavioural response to predators in female guppies (Poecilia reticulata).

    Science.gov (United States)

    van der Bijl, Wouter; Thyselius, Malin; Kotrschal, Alexander; Kolm, Niclas

    2015-08-07

    Large brains are thought to result from selection for cognitive benefits, but how enhanced cognition leads to increased fitness remains poorly understood. One explanation is that increased cognitive ability results in improved monitoring and assessment of predator threats. Here, we use male and female guppies (Poecilia reticulata), artificially selected for large and small brain size, to provide an experimental evaluation of this hypothesis. We examined their behavioural response as singletons, pairs or shoals of four towards a model predator. Large-brained females, but not males, spent less time performing predator inspections, an inherently risky behaviour. Video analysis revealed that large-brained females were further away from the model predator when in pairs but that they habituated quickly towards the model when in shoals of four. Males stayed further away from the predator model than females but again we found no brain size effect in males. We conclude that differences in brain size affect the female predator response. Large-brained females might be able to assess risk better or need less sensory information to reach an accurate conclusion. Our results provide experimental support for the general idea that predation pressure is likely to be important for the evolution of brain size in prey species.

  1. Size, but not experience, affects the ontogeny of constriction performance in ball pythons (Python regius).

    Science.gov (United States)

    Penning, David A; Dartez, Schuyler F

    2016-03-01

    Constriction is a prey-immobilization technique used by many snakes and is hypothesized to have been important to the evolution and diversification of snakes. However, very few studies have examined the factors that affect constriction performance. We investigated constriction performance in ball pythons (Python regius) by evaluating how peak constriction pressure is affected by snake size, sex, and experience. In one experiment, we tested the ontogenetic scaling of constriction performance and found that snake diameter was the only significant factor determining peak constriction pressure. The number of loops applied in a coil and its interaction with snake diameter did not significantly affect constriction performance. Constriction performance in ball pythons scaled differently than in other snakes that have been studied, and medium to large ball pythons are capable of exerting significantly higher pressures than those shown to cause circulatory arrest in prey. In a second experiment, we tested the effects of experience on constriction performance in hatchling ball pythons over 10 feeding events. By allowing snakes in one test group to gain constriction experience, and manually feeding snakes under sedation in another test group, we showed that experience did not affect constriction performance. During their final (10th) feedings, all pythons constricted similarly and with sufficiently high pressures to kill prey rapidly. At the end of the 10 feeding trials, snakes that were allowed to constrict were significantly smaller than their non-constricting counterparts.

  2. Make pupils young researchers!

    Science.gov (United States)

    Gouhier, Armelle

    2015-04-01

    With the 2011 educational reform in France, a new course has been created in secondary schools : Methods & Practices in Science (MPS). The main goal was to improve the pupils working methods in science, including laboratory and field works. In addition, the pedagogy develops pupils autonomy and creativity, a key factor in a research process. Three teachers are working together (Mathematics, Physics and Geology-Biology), showing how different disciplines complement one another. Eventually, this is aimed at attracting more students in scientific sections. This course is optional, in the "seconde" class in French secondary schools (i.e., for 15 years old students). For the next class, they will have to choose between scientific, economic and literature sections : it is a useful option for them to decide which section has their preference. In my high-school in Clermont-Ferrand, we have chosen a research subject on hydrogeology & water quality improvement in region "Auvergne". The pupils will have to develop and set up appropriate tools to check and improve the water quality, related to different disciplines : - Geology & Biology: hydrogeology, effects of different pollutants on aquatic life, solutions to improve water quality (example of the natural water treatment zone in the lake of "Aydat, Auvergne, France"). - Physics & Chemistry: water potability criteria, pollution tests in water, water treatment plants working. - Mathematics: algorithm development, modeling on excel of the dispersion of pollutants The pedagogy of this course is new in French high-schools : pupils work in groups of three, so as to develop cooperation and autonomy. The teachers give the guidelines at the beginning of each working session, and answer the students questions when necessary. The evaluation is competence-based : instead of a mark, which is the main evaluation method in France, the pupils have to evaluate their own skills. Then, the teachers make an evaluation, and the global process is

  3. Sorting it out: bedding particle size and nesting material processing method affect nest complexity.

    Science.gov (United States)

    Robinson-Junker, Amy; Morin, Amelia; Pritchett-Corning, Kathleen; Gaskill, Brianna N

    2017-04-01

    As part of routine husbandry, an increasing number of laboratory mice receive nesting material in addition to standard bedding material in their cages. Nesting material improves health outcomes and physiological performance in mice that receive it. Providing usable nesting material uniformly and efficiently to various strains of mice remains a challenge. The aim of this study was to determine how bedding particle size, method of nesting material delivery, and processing of the nesting material before delivery affected nest building in mice of strong (BALB/cAnNCrl) and weak (C3H/HeNCrl) gathering abilities. Our data suggest that processing nesting material through a grinder in conjunction with bedding material, although convenient for provision of bedding with nesting material 'built-in', negatively affects the integrity of the nesting material and subsequent nest-building outcomes. We also found that C3H mice, previously thought to be poor nest builders, built similarly scored nests to those of BALB/c mice when provided with unprocessed nesting material. This was true even when nesting material was mixed into the bedding substrate. We also observed that when nesting material was mixed into the bedding substrate, mice of both strains would sort their bedding by particle size more often than if it were not mixed in. Our findings support the utility of the practice of distributing nesting material mixed in with bedding substrate, but not that of processing the nesting material with the bedding in order to mix them.

  4. Atrazine exposure affects longevity, development time and body size in Drosophila melanogaster.

    Science.gov (United States)

    Marcus, Sarah R; Fiumera, Anthony C

    2016-01-01

    Atrazine is the one of the most widely used herbicides in the United States and non-target organisms may encounter it in the environment. Atrazine is known to affect male reproduction in both vertebrates and invertebrates but less is known about its effects on other fitness traits. Here we assessed the effects of five different chronic exposure levels on a variety of fitness traits in Drosophila melanogaster. We measured male and female longevity, development time, proportion pupated, proportion emerged, body size, female mating rate, fertility and fecundity. Atrazine exposure decreased the proportion pupated, the proportion emerged and adult survival. Development time was also affected by atrazine and exposed flies pupated and emerged earlier than controls. Although development time was accelerated, body size was actually larger in some of the exposures. Atrazine exposure had no effect on female mating rate and the effects on female fertility and fecundity were only observed in one of the two independent experimental blocks. Many of the traits showed non-monotonic dose response curves, where the intermediate concentrations showed the largest effects. Overall this study shows that atrazine influences a variety of life history traits in the model genetic system, D. melanogaster, and future studies should aim to identify the molecular mechanisms of toxicity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Do class size effects differ across grades?

    DEFF Research Database (Denmark)

    Nandrup, Anne Brink

    This paper contributes to the class size literature by analyzing whether short-run class size effects are constant across grade levels in compulsory school. Results are based on administrative data on all pupils enroled in Danish public schools. Identification is based on a government-imposed class...... size cap that creates exogenous variation in class sizes. Significant (albeit modest) negative effects of class size increases are found for children on primary school levels. The effects on math abilities are statistically different across primary and secondary school. Larger classes do not affect...

  6. Fruit size QTLs affect in a major proportion the yield in tomato

    Directory of Open Access Journals (Sweden)

    Aurelio Hernández-Bautista

    2015-12-01

    Full Text Available Yield is a complex trait that is affected by several genetic and environmental factors. Yield is defined as the amount of the part of interest that is harvested from a crop plant in a given area. We investigated the genetic basis of yield in an F2 population derived from a cross between Solatium lycopersicum L. and its most closely related wild species S. pimpinellifolium L. We found that average fruit weight, fruit diameter, and fruit length had a strong effect on yield. In addition, small effects on yield due to soluble solids content and locule number were also observed. A total of 25 different significant quantitative trait locus (QTLs were detected for six traits (fruit length and diameter, fruit weight, yield, locule number, and Brix degrees. The percentage of phenotypic variation associated with single QTLs ranged from 4.19% to 12.67%. A strong co-location of QTLs among yield and fruit size traits was observed, suggesting that these QTLs play a role in the same expression process controlling yield. We also realized that the effects of soluble solids content on yield could be due to direct effects of fruit size QTLs linked to genes controlling soluble solids content. This result then may suggest that yield in tomato is mainly formed by fruit size QTLs, whereas the remaining factors may play a complementary role in the expression of tomato yield.

  7. Pupil Masks for Spectrophotometry of Transiting Exoplanets

    Science.gov (United States)

    Itoh, Satoshi; Matsuo, Taro; Goda, Shohei; Shibai, Hiroshi; Sumi, Takahiro

    2017-09-01

    Spectrophotometric stability, which is crucial in the spectral characterization of transiting exoplanets, is affected by photometric variations arising from field-stop loss in space telescopes with pointing jitter or primary mirror deformation. This paper focuses on a new method for removing slit-loss or field-stop-loss photometric variation through the use of a pupil mask. Two types of pupil function are introduced: the first uses conventional (e.g., Gaussian or hyper-Gaussian) apodizing patterns; whereas the second, which we call a block-shaped mask, employs a new type of pupil mask designed for high photometric stability. A methodology for the optimization of a pupil mask for transit observations is also developed. The block-shaped mask can achieve a photometric stability of 10-5 for a nearly arbitrary field-stop radius when the pointing jitter is smaller than approximately 0.7λ /D and a photometric stability of 10-6 at a pointing jitter smaller than approximately 0.5λ /D. The impact of optical aberrations and mask imperfections upon mask performance is also discussed.

  8. Fathers matter: male body mass affects life-history traits in a size-dimorphic seabird.

    Science.gov (United States)

    Cornioley, Tina; Jenouvrier, Stéphanie; Börger, Luca; Weimerskirch, Henri; Ozgul, Arpat

    2017-05-17

    One of the predicted consequences of climate change is a shift in body mass distributions within animal populations. Yet body mass, an important component of the physiological state of an organism, can affect key life-history traits and consequently population dynamics. Over the past decades, the wandering albatross-a pelagic seabird providing bi-parental care with marked sexual size dimorphism-has exhibited an increase in average body mass and breeding success in parallel with experiencing increasing wind speeds. To assess the impact of these changes, we examined how body mass affects five key life-history traits at the individual level: adult survival, breeding probability, breeding success, chick mass and juvenile survival. We found that male mass impacted all traits examined except breeding probability, whereas female mass affected none. Adult male survival increased with increasing mass. Increasing adult male mass increased breeding success and mass of sons but not of daughters. Juvenile male survival increased with their chick mass. These results suggest that a higher investment in sons by fathers can increase their inclusive fitness, which is not the case for daughters. Our study highlights sex-specific differences in the effect of body mass on the life history of a monogamous species with bi-parental care. © 2017 The Authors.

  9. Nano-sized polystyrene affects feeding, behavior and physiology of brine shrimp Artemia franciscana larvae.

    Science.gov (United States)

    Bergami, Elisa; Bocci, Elena; Vannuccini, Maria Luisa; Monopoli, Marco; Salvati, Anna; Dawson, Kenneth A; Corsi, Ilaria

    2016-01-01

    Nano-sized polymers as polystyrene (PS) constitute one of the main challenges for marine ecosystems, since they can distribute along the whole water column affecting planktonic species and consequently disrupting the energy flow of marine ecosystems. Nowadays very little knowledge is available on the impact of nano-sized plastics on marine organisms. Therefore, the present study aims to evaluate the effects of 40nm anionic carboxylated (PS-COOH) and 50nm cationic amino (PS-NH2) polystyrene nanoparticles (PS NPs) on brine shrimp Artemia franciscana larvae. No signs of mortality were observed at 48h of exposure for both PS NPs at naplius stage but several sub-lethal effects were evident. PS-COOH (5-100μg/ml) resulted massively sequestered inside the gut lumen of larvae (48h) probably limiting food intake. Some of them were lately excreted as fecal pellets but not a full release was observed. Likewise, PS-NH2 (5-100µg/ml) accumulated in larvae (48h) but also adsorbed at the surface of sensorial antennules and appendages probably hampering larvae motility. In addition, larvae exposed to PS-NH2 undergo multiple molting events during 48h of exposure compared to controls. The activation of a defense mechanism based on a physiological process able to release toxic cationic NPs (PS-NH2) from the body can be hypothesized. The general observed accumulation of PS NPs within the gut during the 48h of exposure indicates a continuous bioavailability of nano-sized PS for planktonic species as well as a potential transfer along the trophic web. Therefore, nano-sized PS might be able to impair food uptake (feeding), behavior (motility) and physiology (multiple molting) of brine shrimp larvae with consequences not only at organism and population level but on the overall ecosystem based on the key role of zooplankton on marine food webs.

  10. Genetic variations in FSH action affect sex hormone levels and breast tissue size in infant girls

    DEFF Research Database (Denmark)

    Henriksen, Louise Scheutz; Hagen, Casper P; Assens, Maria

    2016-01-01

    , especially FSHR -29G>A and FSHR 2039A>G, affect female hormone profile and glandular breast tissue development already during minipuberty. Thus, genetic variations of FSH signaling appear to determine the individual set point of the hypothalamic-pituitary-gonadal axis already early in life.......Context: Single nucleotide polymorphisms altering FSH action (FSHB -211G>T, FSHR -29G>A, and FSHR 2039A>G) are associated with peripubertal and adult levels of reproductive hormones and age at pubertal onset in girls. Objective: To investigate whether genetic polymorphisms altering FSH action...... present in homozygotes. FSHB -211T carriers had smaller breast tissue size than girls who without a minor allele; GT+TT 10.5 (confidence interval 9.4 -11.5) mm vs GG 12.1 (confidence interval 11.4-12.8) mm, P = .014. Conclusions: Our study indicates that 3 genetic polymorphisms altering FSH action...

  11. Selective Rapid Eye Movement Sleep Deprivation Affects Cell Size and Number in Kitten Locus Coeruleus

    Directory of Open Access Journals (Sweden)

    James P Shaffery

    2012-05-01

    Full Text Available Cells in the locus coeruleus (LC constitute the sole source of norepinephrine (NE in the brain, and change their discharge rates according to vigilance state. In addition to its well established role in vigilance, NE affects synaptic plasticity in the postnatal critical period (CP of development. One form of CP synaptic plasticity affected by NE results from monocular occlusion, which leads to physiological and cytoarchitectural alterations in central visual areas. Selective suppression of rapid eye movement sleep (REMS in the CP kitten enhances the central effects of monocular occlusion. The mechanisms responsible for heightened cortical plasticity following REMS deprivation (REMSD remain undetermined. One possible mediator of an increase in plasticity is continuous NE outflow, which presumably persists during extended periods of REMSD. Tyrosine hydroxylase (TH is the rate-limiting enzyme in the synthesis of NE and serves as a marker for NE-producing cells. We selectively suppressed REMS in kittens for one week during the CP. The number and size of LC cells expressing immunoreactivity to tyrosine hydroxylase (TH-ir was assessed in age-matched REMS-deprived (RD-, treatment-control (TXC-, and home cage-reared (HCC animals. Sleep amounts and slow wave activity (SWA were also examined relative to baseline. Time spent in REMS during the study was lower in RD compared to TXC animals, and RD kittens increased SWA delta power in the latter half of the REMSD period. The estimated total number of TH-ir cells in LC was significantly lower in the RD- than in the TXC kittens and numerically lower than in HCC animals. The size of LC cells expressing TH-ir was greatest in the HCC group. They were significantly larger than the cells in the RD kittens. These data are consistent with a possible reduction in NE in forebrain areas, including visual cortex, caused by one week of REMSD.

  12. Group size and nest spacing affect Buggy Creek virus (Togaviridae: Alphavirus infection in nestling house sparrows.

    Directory of Open Access Journals (Sweden)

    Valerie A O'Brien

    Full Text Available The transmission of parasites and pathogens among vertebrates often depends on host population size, host species diversity, and the extent of crowding among potential hosts, but little is known about how these variables apply to most vector-borne pathogens such as the arboviruses (arthropod-borne viruses. Buggy Creek virus (BCRV; Togaviridae: Alphavirus is an RNA arbovirus transmitted by the swallow bug (Oeciacus vicarius to the cliff swallow (Petrochelidon pyrrhonota and the introduced house sparrow (Passer domesticus that has recently invaded swallow nesting colonies. The virus has little impact on cliff swallows, but house sparrows are seriously affected by BCRV. For house sparrows occupying swallow nesting colonies in western Nebraska, USA, the prevalence of BCRV in nestling sparrows increased with sparrow colony size at a site but decreased with the number of cliff swallows present. If one nestling in a nest was infected with the virus, there was a greater likelihood that one or more of its nest-mates would also be infected than nestlings chosen at random. The closer a nest was to another nest containing infected nestlings, the greater the likelihood that some of the nestlings in the focal nest would be BCRV-positive. These results illustrate that BCRV represents a cost of coloniality for a vertebrate host (the house sparrow, perhaps the first such demonstration for an arbovirus, and that virus infection is spatially clustered within nests and within colonies. The decreased incidence of BCRV in sparrows as cliff swallows at a site increased reflects the "dilution effect," in which virus transmission is reduced when a vector switches to feeding on a less competent vertebrate host.

  13. Group size and nest spacing affect Buggy Creek virus (Togaviridae: Alphavirus) infection in nestling house sparrows.

    Science.gov (United States)

    O'Brien, Valerie A; Brown, Charles R

    2011-01-01

    The transmission of parasites and pathogens among vertebrates often depends on host population size, host species diversity, and the extent of crowding among potential hosts, but little is known about how these variables apply to most vector-borne pathogens such as the arboviruses (arthropod-borne viruses). Buggy Creek virus (BCRV; Togaviridae: Alphavirus) is an RNA arbovirus transmitted by the swallow bug (Oeciacus vicarius) to the cliff swallow (Petrochelidon pyrrhonota) and the introduced house sparrow (Passer domesticus) that has recently invaded swallow nesting colonies. The virus has little impact on cliff swallows, but house sparrows are seriously affected by BCRV. For house sparrows occupying swallow nesting colonies in western Nebraska, USA, the prevalence of BCRV in nestling sparrows increased with sparrow colony size at a site but decreased with the number of cliff swallows present. If one nestling in a nest was infected with the virus, there was a greater likelihood that one or more of its nest-mates would also be infected than nestlings chosen at random. The closer a nest was to another nest containing infected nestlings, the greater the likelihood that some of the nestlings in the focal nest would be BCRV-positive. These results illustrate that BCRV represents a cost of coloniality for a vertebrate host (the house sparrow), perhaps the first such demonstration for an arbovirus, and that virus infection is spatially clustered within nests and within colonies. The decreased incidence of BCRV in sparrows as cliff swallows at a site increased reflects the "dilution effect," in which virus transmission is reduced when a vector switches to feeding on a less competent vertebrate host.

  14. Xanthine dehydrogenase and aldehyde oxidase impact plant hormone homeostasis and affect fruit size in 'Hass' avocado.

    Science.gov (United States)

    Taylor, Nicky J; Cowan, A Keith

    2004-04-01

    The contribution of xanthine dehydrogenase (XDH, EC 1.1.1.204) to fruit size was investigated using the normal and small-fruit variants of Persea americana Mill. cv. 'Hass'. Inhibition of XDH by treatment of normal fruit, in the linear phase of growth (phase II), with allopurinol (Allo) arrested fruit growth. Adenine (Ade), a less effective inhibitor of this enzyme, also arrested fruit growth when applied in phase II and slowed fruit growth when applied in phase III. A time-course study on the activity of XDH in mesocarp tissue from normal and small fruit showed that maximum activity occurred late in phase II and that the peak in activity was absent in mesocarp of the small fruit. Feeding Ade to growing fruit in phase III caused a transient decline in fruit growth (measured as change in fruit length). Thereafter, growth resumed although fruit size was irreversibly affected. Treatment of fruit with Ade and Ade-containing cytokinins altered activity of another molybdenum enzyme, aldehyde oxidase (EC 1.2.3.1). Cytokinin oxidase was induced by cytokinin and auxin. Purine catabolism via hypoxanthine/xanthine was operative in normal fruit and in mesocarp from the small-fruit variant and as expected, Allo treatment caused accumulation of xanthine and adenine. In the absence of an increase in XDH during growth of the small-fruit phenotype, low levels of Ade were interpreted as resulting from respiration-enhanced adenylate depletion. Stress and/or pathogen induction of the alternative oxidase pathway is proposed as a possible cause.

  15. Emulsion oil droplet size significantly affects satiety: A pre-ingestive approach.

    Science.gov (United States)

    Lett, Aaron M; Norton, Jennifer E; Yeomans, Martin R

    2016-01-01

    Previous research has demonstrated that the manipulation of oil droplet size within oil-in-water emulsions significantly affects sensory characteristics, hedonics and expectations of food intake, independently of energy content. Smaller oil droplets enhanced perceived creaminess, increased Liking and generated greater expectations of satiation and satiety, indicating that creaminess is a satiety-relevant sensory cue within these systems. This paper extends these findings by investigating the effect of oil droplet size (d4,3: 2 and 50 μm) on food intake and appetite. Male participants (n = 34 aged 18-37; BMI of 22.7 ± 1.6 kg/m(2); DEBQ restricted eating score of 1.8 ± 0.1.) completed two test days, where they visited the laboratory to consume a fixed-portion breakfast, returning 3 h later for a "drink", which was the emulsion preload containing either 2 or 50 μm oil droplets. This was followed 20 min later with an ad libitum pasta lunch. Participants consumed significantly less at the ad libitum lunch after the preload containing 2 μm oil droplets than after the 50 μm preload, with an average reduction of 12% (62.4 kcal). Despite the significant differences in intake, no significant differences in sensory characteristics were noted. The findings show that the impact that an emulsion has on satiety can be enhanced without producing significantly perceivable differences in sensory properties. Therefore, by introducing a processing step which results in a smaller droplets, emulsion based liquid food products can be produced that enhance satiety, allowing covert functional redesign. Future work should consider the mechanism responsible for this effect.

  16. Container size and growing media affects water use efficiency in a Gerbera jamesonii cut flower crop

    Directory of Open Access Journals (Sweden)

    Libertad Mascarini

    2012-10-01

    Full Text Available Two containers (4 and 8 L plastic pots and three growing media mixture types (0/100, 25/75 and 50/50 % of peat/perlite were used, with the aim of determining the optimum combination for gerbera cut flower crop, considering both commercial productivity (yield and quality of cut flowers and environmental impact, (water and fertilizer use efficiency. The best combination in the first year of production was 8 L and 0/100, followed of 4 and 8 L with the 25/75, with a yield of 53.4, 30.5 and 29.7 flowers m-2 respectively. The yield of the rest of the treatments were similar, around 20 flowers m-2. Commercial cut flower quality was aceptable in all treatments. Considering the efficiency measured as the ratio water used per flower harvested, 8L 0/100 was clearly superior with a value of 1.23 L/flower, the rest of the treatments were between 2.17 y 4.14 L/flower, keeping relation as much with container size like with growing media mixture. The importance of these results is the simultaneous consideration of many factors which affect both comercial profitability and development of sustainable technology for intensive crops.

  17. Researchers' choice of the number and range of levels in experiments affects the resultant variance-accounted-for effect size.

    Science.gov (United States)

    Okada, Kensuke; Hoshino, Takahiro

    2016-08-08

    In psychology, the reporting of variance-accounted-for effect size indices has been recommended and widely accepted through the movement away from null hypothesis significance testing. However, most researchers have paid insufficient attention to the fact that effect sizes depend on the choice of the number of levels and their ranges in experiments. Moreover, the functional form of how and how much this choice affects the resultant effect size has not thus far been studied. We show that the relationship between the population effect size and number and range of levels is given as an explicit function under reasonable assumptions. Counterintuitively, it is found that researchers may affect the resultant effect size to be either double or half simply by suitably choosing the number of levels and their ranges. Through a simulation study, we confirm that this relation also applies to sample effect size indices in much the same way. Therefore, the variance-accounted-for effect size would be substantially affected by the basic research design such as the number of levels. Simple cross-study comparisons and a meta-analysis of variance-accounted-for effect sizes would generally be irrational unless differences in research designs are explicitly considered.

  18. Speckle imaging through turbulent atmosphere based on adaptable pupil segmentation.

    Science.gov (United States)

    Loktev, Mikhail; Soloviev, Oleg; Savenko, Svyatoslav; Vdovin, Gleb

    2011-07-15

    We report on the first results to our knowledge obtained with adaptable multiaperture imaging through turbulence on a horizontal atmospheric path. We show that the resolution can be improved by adaptively matching the size of the subaperture to the characteristic size of the turbulence. Further improvement is achieved by the deconvolution of a number of subimages registered simultaneously through multiple subapertures. Different implementations of multiaperture geometry, including pupil multiplication, pupil image sampling, and a plenoptic telescope, are considered. Resolution improvement has been demonstrated on a ∼550 m horizontal turbulent path, using a combination of aperture sampling, speckle image processing, and, optionally, frame selection. © 2011 Optical Society of America

  19. Illusory Shrinkage and Growth: Body-Based Rescaling Affects the Perception of Size

    NARCIS (Netherlands)

    Linkenauger, S.A.; Ramenzoni, V.C.; Proffitt, D.R.

    2010-01-01

    The notion that apparent sizes are perceived relative to the size of one's body is supported through the discovery of a new visual illusion. When graspable objects are magnified by magnifying goggles, they appear to shrink back to near-normal size when one's hand (also magnified) is placed next to t

  20. [Tonic pupil caused by ischemia].

    Science.gov (United States)

    Wilhelm, H

    1989-01-01

    Tonic pupil is usually an idiopathic condition. In some cases, the cause of the ciliary ganglion lesion leading to tonic pupils is obvious. Rarely ischemia causes a lesion of the ciliary ganglion or the short ciliary nerves due to the good blood supply of the ciliary ganglion. Only two cases of tonic pupils in the course of giant cell arteritis are mentioned in the literature, but tonic pupils are probably much more common with this disease. Five cases are demonstrated here. All had associated ischemic optic neuropathy, and stagnation of the blood flow in the supratrochlear artery could be demonstrated in two cases by Doppler sonography. Tonic pupils may also occur when an oclusion of the internal carotid artery resolves, probably because of transient stasis of the orbital blood flow. In another case, tonic pupils were associated with choroidal ischemia (proved by video fluorescent angiography) of unknown origin. The diagnosis of tonic pupils was made by pharmacological testing for cholinergic hypersensitivity with 0.1% pilocarpine.

  1. Pupils have rights too

    Directory of Open Access Journals (Sweden)

    Banjanin-Đuričić Nada

    2010-01-01

    Full Text Available The text points out the delicate problem of inadequate treatment of pupils by teachers. Such treatment may include insults, verbal aggression, sarcasm, but also the double meaning of the message in which it is hard to prove violation of pupils’ personality. Although characteristics of desirable relationship of teachers toward children are specified by the Convention on the Rights of the Child, Law on Foundations of the Education and Upbringing System, as well as by the Protocol for Protection of Children and Students from Violence, Abuse and Neglect in Educational Institutions, verbal aggression is still present, but often unrecognized as a form of violation of pupils’ rights - right to respect of personality and right to development. The text describes an attempt, almost an experiment, in the form of workshop model that can contribute to recognition of this problem and help in finding constructive ways to overcome it.

  2. PRAGMATIC ABILITIES OF PUPILS WITH MILD INTELLECTUAL DISABILITIES

    Directory of Open Access Journals (Sweden)

    Mateja SHILC

    2017-03-01

    Full Text Available The research analyses characteristics of pragmatic abilities of storytelling of pupils with mild intellectual disabilities (MID, in the light of vocabulary characteristics, grammar structure and substantive structure of a story, considering their age and gender. The sample consists of 60 pupils with MID, aged 7 to 9, who attend special school. Child’s pragmatic abilities are assessed with The Storytelling Test. The research results reveal considerable progress of the older group in vocabulary, whereas the progress in grammatical and substantive structure was less substantial. When comparing achievements of pupils with MID according to the vocabulary, grammatical and substantive story structure, no gender differences are determined. A comparison of pragmatic abilities of younger and older groups of pupils with MID with the norms for peers with typical development shows minor deviation of the younger group. The research results reveal characteristics of pragmatic abilities of pupils with MID and can provide insights to speech therapists, teachers, special education teachers and counsellors when considering profiles of individuals that are taken as a basis for designing intervention programs. By implementing such program, we would encourage development of pragmatic abilities of pupils, thus affecting their academic achievements, communication competency and social skills.

  3. The effect of pupil dilation on AL-Scan biometric parameters.

    Science.gov (United States)

    Can, Ertuğrul; Duran, Mustafa; Çetinkaya, Tuğba; Arıtürk, Nurşen

    2016-04-01

    The purpose of this study was to investigate the effects of pupil dilation on the parameters of the AL-Scan (Nidek Co., Ltd, Gamagori, Japan). We compared the measurements of axial length (AL), anterior chamber depth (ACD), central corneal keratometry reading, pupil diameter, and intraocular lens (IOL) power of 72 eyes of 72 healthy volunteers and patients scheduled for cataract surgery before and 45 min after instillation of cyclopentolate hydrochloride 1 % using the AL-Scan. Intraobserver repeatability was assessed by taking three consecutive recordings of ACD and AL. Only ACD readings were significantly different between predilation and postdilation (P  0.001). Only two cases in the study demonstrated changes in IOL power higher than 0.5 D. The intraobserver repeatability of both devices was good (CV values for ACD and AL were 0.16 and 0.20 %, respectively). Dilated pupil size did not affect the measurement of IOL power using the A-Scan optical biometer, but increase in ACD after dilation should be taken into account when performing refractive surgeries in which ACD is very important such as phakic anterior chamber IOL implantation.

  4. Pupil geometry and pupil re-imaging in telescope arrays

    Science.gov (United States)

    Traub, Wesley A.

    1990-01-01

    This paper considers the issues of lateral and longitudinal pupil geometry in ground-based telescope arrays, such as IOTA. In particular, it is considered whether or not pupil re-imaging is required before beam combination. By considering the paths of rays through the system, an expression is derived for the optical path errors in the combined wavefront as a function of array dimensions, telescope magnification factor, viewing angle, and field-of-view. By examining this expression for the two cases of pupil-plane and image-plane combination, operational limits can be found for any array. As a particular example, it is shown that for IOTA no pupil re-imaging optics will be needed.

  5. Pupil dilation in the Simon task as a marker of conflict processing.

    Science.gov (United States)

    van Steenbergen, Henk; Band, Guido P H

    2013-01-01

    Cognitive demands in response conflict paradigms trigger negative affect and avoidance behavior. However, not all response conflict studies show increases in physiological indices of emotional arousal, such as pupil diameter. In contrast to earlier null-results, this study shows for the first time that small (about 0.02 mm) conflict-related pupil dilation can be observed in a Simon task when stimuli do not introduce a light reflex. Results show that response-conflict in Simon trials induces both pupil dilation and reaction-time costs. Moreover, sequential analyses reveal that pupil dilation mirrors the conflict-adaptation pattern observed in reaction time (RT). Although single-trial regression analyses indicated that pupil dilation is likely to reflect more than one process at the same time, in general our findings imply that pupil dilation can be used as an indirect marker of conflict processing.

  6. Pupil Dilation in the Simon Task as a Marker of Conflict Processing

    Directory of Open Access Journals (Sweden)

    Henk eVan Steenbergen

    2013-05-01

    Full Text Available Cognitive demands in response conflict paradigms trigger negative affect and avoidance behavior. However, not all response conflict studies show increases in physiological indices of emotional arousal, such as pupil diameter. In contrast to earlier null-results, this study shows for the first time that small (about 0.02 mm conflict-related pupil dilation can be observed in a Simon task when stimuli do not introduce a light reflex. Results show that response-conflict in Simon trials induces both pupil dilation and reaction-time costs. Moreover, sequential analyses reveal that pupil dilation mirrors the conflict-adaptation pattern observed in reaction time. Although single-trial regression analyses indicated that pupil dilation is likely to reflect more than one process at the same time, in general our findings imply that pupil dilation can be used as an indirect marker of conflict processing.

  7. Changes in pollinator fauna affect altitudinal variation of floral size in a bumblebee-pollinated herb.

    Science.gov (United States)

    Nagano, Yusuke; Abe, Kota; Kitazawa, Tomoaki; Hattori, Mitsuru; Hirao, Akira S; Itino, Takao

    2014-09-01

    Geographic trait variations are often caused by locally different selection regimes. As a steep environmental cline along altitude strongly influences adaptive traits, mountain ecosystems are ideal for exploring adaptive differentiation over short distances. We investigated altitudinal floral size variation of Campanula punctata var. hondoensis in 12 populations in three mountain regions of central Japan to test whether the altitudinal floral size variation was correlated with the size of the local bumblebee pollinator and to assess whether floral size was selected for by pollinator size. We found apparent geographic variations in pollinator assemblages along altitude, which consequently produced a geographic change in pollinator size. Similarly, we found altitudinal changes in floral size, which proved to be correlated with the local pollinator size, but not with altitude itself. Furthermore, pollen removal from flower styles onto bees (plant's male fitness) was strongly influenced by the size match between flower style length and pollinator mouthpart length. These results strongly suggest that C. punctata floral size is under pollinator-mediated selection and that a geographic mosaic of locally adapted C. punctata exists at fine spatial scale.

  8. Infant and adult pupil dilation in response to unexpected sounds.

    Science.gov (United States)

    Wetzel, Nicole; Buttelmann, David; Schieler, Andy; Widmann, Andreas

    2016-04-01

    Surprisingly occurring sounds outside the focus of attention can involuntarily capture attention. This study focuses on the impact of deviant sounds on the pupil size as a marker of auditory involuntary attention in infants. We presented an oddball paradigm including four types of deviant sounds within a sequence of repeated standard sounds to 14-month-old infants and to adults. Environmental and noise deviant sounds elicited a strong pupil dilation response (PDR) in both age groups. In contrast, moderate frequency deviants elicited a significant PDR in adults only. Moreover, a principal component analysis revealed two components underlying the PDR. Component scores differ, depending on deviant types, between age groups. Results indicate age effects of parasympathetic inhibition and sympathetic activation of the pupil size caused by deviant sounds with a high arousing potential. Results demonstrate that the PDR is a sensitive tool for the investigation of involuntary attention to sounds in preverbal children.

  9. Does Market Size Structure Affect Competition? The Case of Small Business Lending

    OpenAIRE

    Allen N. Berger; Richard J. Rosen; Udell, Gregory F.

    2005-01-01

    Market size structure refers to the distribution of shares of different size classes of local market participants, where the sizes are inclusive of assets both within and outside the local market. We apply this new measure of market structure in two empirical analyses of the U.S. banking industry to address concerns regarding the effects of the consolidation in banking. Our quantity analysis of the likelihood that small businesses borrow from large versus small banks and our small business lo...

  10. Teaching Styles and Pupil Progress

    Science.gov (United States)

    Rogers, Vincent; Baron, Joan

    1977-01-01

    Critically analyzes Neville Bennett's book "Teaching Styles and Pupil Progress," which found that formal teaching styles are more closely associated with student achievement in "basic skills" than are informal styles. (IRT)

  11. Sexual selection in cane toads Rhinella marina: A male’s body size affects his success and his tactics

    Directory of Open Access Journals (Sweden)

    Haley BOWCOCK, Gregory P. BROWN, Richard SHINE

    2013-12-01

    Full Text Available Male body size can play an important role in the mating systems of anuran amphibians. We conducted laboratory-based trials with cane toads Rhinella (Bufo marina from an invasive population in the wet-dry tropics of northern Australia, to clarify the effects of a male's body size on his reproductive success and behavior (mate choice. Males were stimulated with a synthetic hormone to induce reproductive readiness. Larger body size enhanced a male toad's ability to displace a smaller rival from amplexus, apparently because of physical strength: more force was required to dislodge a larger than a smaller amplectant male. A male’s body size also affected his mate-choice criteria. Males of all body sizes were as likely to attempt amplexus with another male as with a female of the same size, and preferred larger rather than smaller sexual targets. However, this size preference was stronger in larger males and hence, amplexus was size-assortative. This pattern broke down when males were given access to already-amplectant male-female pairs: males of all body sizes readily attempted amplexus with the pair, with no size discrimination. An amplectant pair provides a larger visual stimulus, and prolonged amplexus provides a strong cue for sex identification (one of the individuals involved is almost certainly a female. Thus, a male cane toad’s body size affects both his ability to defeat rivals in physical struggles over females, and the criteria he uses when selecting potential mates, but the impacts of that selectivity depend upon the context in which mating occurs [Current Zoology 59 (6: 747–753, 2013].

  12. Pupil-linked arousal determines variability in perceptual decision making.

    Science.gov (United States)

    Murphy, Peter R; Vandekerckhove, Joachim; Nieuwenhuis, Sander

    2014-09-01

    Decision making between several alternatives is thought to involve the gradual accumulation of evidence in favor of each available choice. This process is profoundly variable even for nominally identical stimuli, yet the neuro-cognitive substrates that determine the magnitude of this variability are poorly understood. Here, we demonstrate that arousal state is a powerful determinant of variability in perceptual decision making. We measured pupil size, a highly sensitive index of arousal, while human subjects performed a motion-discrimination task, and decomposed task behavior into latent decision making parameters using an established computational model of the decision process. In direct contrast to previous theoretical accounts specifying a role for arousal in several discrete aspects of decision making, we found that pupil diameter was uniquely related to a model parameter representing variability in the rate of decision evidence accumulation: Periods of increased pupil size, reflecting heightened arousal, were characterized by greater variability in accumulation rate. Pupil diameter also correlated trial-by-trial with specific patterns of behavior that collectively are diagnostic of changing accumulation rate variability, and explained substantial individual differences in this computational quantity. These findings provide a uniquely clear account of how arousal state impacts decision making, and may point to a relationship between pupil-linked neuromodulation and behavioral variability. They also pave the way for future studies aimed at augmenting the precision with which people make decisions.

  13. Large pupils predict goal-driven eye movements.

    Science.gov (United States)

    Mathôt, Sebastiaan; Siebold, Alisha; Donk, Mieke; Vitu, Françoise

    2015-06-01

    Here we report that large pupils predict fixations of the eye on low-salient, inconspicuous parts of a visual scene. We interpret this as showing that mental effort, reflected by a dilation of the pupil, is required to guide gaze toward objects that are relevant to current goals, but that may not be very salient. When mental effort is low, reflected by a constriction of the pupil, the eyes tend to be captured by high-salient parts of the image, irrespective of top-down goals. The relationship between pupil size and visual saliency was not driven by luminance or a range of other factors that we considered. Crucially, the relationship was strongest when mental effort was invested exclusively in eye-movement control (i.e., reduced in a dual-task setting), which suggests that it is not due to general effort or arousal. Our finding illustrates that goal-driven control during scene viewing requires mental effort, and that pupil size can be used as an online measure to track the goal-drivenness of behavior. (c) 2015 APA, all rights reserved).

  14. Pupil Control Ideology and Behavior and the Quality of School Life.

    Science.gov (United States)

    Lunenburg, Frederick C.; Schmidt, Linda J.

    More information is needed about the quality of school life, especially as it affects students' attitudes toward school. This paper contrasts pupil control ideologies and the types of school climates they engender in order to determine their effects on the quality of school life. Pupil control ideology and teacher behavior are conceptualized along…

  15. Climate change affects low trophic level marine consumers: warming decreases copepod size and abundance.

    Science.gov (United States)

    Garzke, Jessica; Ismar, Stefanie M H; Sommer, Ulrich

    2015-03-01

    Concern about climate change has re-ignited interest in universal ecological responses to temperature variations: (1) biogeographical shifts, (2) phenology changes, and (3) size shifts. In this study we used copepods as model organisms to study size responses to temperature because of their central role in the pelagic food web and because of the ontogenetic length constancy between molts, which facilitates the definition of size of distinct developmental stages. In order to test the expected temperature-induced shifts towards smaller body size and lower abundances under warming conditions, a mesocosm experiment using plankton from the Baltic Sea at three temperature levels (ambient, ambient +4 °C, ambient -4 °C) was performed in summer 2010. Overall copepod and copepodit abundances, copepod size at all life stages, and adult copepod size in particular, showed significant temperature effects. As expected, zooplankton peak abundance was lower in warm than in ambient treatments. Copepod size-at-immature stage significantly increased in cold treatments, while adult size significantly decreased in warm treatments.

  16. Calibration of radiographs by a reference metal ball affects preoperative selection of implant size.

    Science.gov (United States)

    Schropp, Lars; Stavropoulos, Andreas; Gotfredsen, Erik; Wenzel, Ann

    2009-12-01

    The aim was to evaluate the impact of a reference ball for calibration of periapical and panoramic radiographs on preoperative selection of implant size for three implant systems. Presurgical digital radiographs (70 panoramic, 43 periapical) from 70 patients scheduled for single-tooth implant treatment, recorded with a metal ball placed in the edentulous area, were evaluated by three observers with the intent to select the appropriate implant size. Four reference marks corresponding to the margins of the metal ball were manually placed on the digital image by means of computer software. Additionally, an implant with proper dimensions for the respective site was outlined by manually placing four reference marks. The diameter of the metal ball and the unadjusted length and width of the implant were calculated. Implant size was adjusted according to a "standard" calibration method (SCM; magnification factor 1.25 in panoramic images and 1.05 in periapical images) and according to a reference ball calibration method (RCM; true magnification). Based on the unadjusted as well as the adjusted implant dimensions, the implant size was selected among those available in a given implant system. For periapical radiographs, when comparing SCM and RCM with unadjusted implant dimensions, implant size changed in 42% and 58%, respectively. When comparing SCM and RCM, implant size changed in 24%. For panoramic radiographs, comparing SCM and RCM changed implant size in 48%. The use of a reference metal ball for calibration of periapical and panoramic radiographs when selecting implant size during treatment planning might be advantageous.

  17. Population size and habitat quality affect genetic diversity and fitness in the clonal herb Cirsium dissectum

    NARCIS (Netherlands)

    Vere, de N.; Jongejans, E.; Plowman, A.; Williams, E.

    2009-01-01

    Remaining populations of plant species in fragmented landscapes are threatened by declining habitat quality and reduced genetic diversity, but the interactions of these major factors are rarely studied together for species conservation. In this study, the interactions between population size,

  18. Male size composition affects male reproductive variance in Atlantic cod Gadus morhua L. spawning aggregations

    DEFF Research Database (Denmark)

    Bekkevold, Dorte

    2006-01-01

    Estimates of Atlantic cod Gadus morhua reproductive success, determined using experimental spawning groups and genetic paternity assignment of offspring, showed that within-group variance in male size correlated positively with the degree of male mating skew, predicting a decrease in male...... reproductive skew with decreasing size variation among males under natural conditions. (c) 2006 The Author Journal compilation (c) 2006 The Fisheries Society of the British Isles...

  19. Particulate size of microalgal biomass affects hydrolysate properties and bioethanol concentration.

    Science.gov (United States)

    Harun, Razif; Danquah, Michael K; Thiruvenkadam, Selvakumar

    2014-01-01

    Effective optimization of microalgae-to-bioethanol process systems hinges on an in-depth characterization of key process parameters relevant to the overall bioprocess engineering. One of the such important variables is the biomass particle size distribution and the effects on saccharification levels and bioethanol titres. This study examined the effects of three different microalgal biomass particle size ranges, 35 μm ≤ x ≤ 90 μm, 125 μm ≤ x ≤ 180 μm, and 295 μm ≤ x ≤ 425 μm, on the degree of enzymatic hydrolysis and bioethanol production. Two scenarios were investigated: single enzyme hydrolysis (cellulase) and double enzyme hydrolysis (cellulase and cellobiase). The glucose yield from biomass in the smallest particle size range (35 μm ≤ x ≤ 90 μm) was the highest, 134.73 mg glucose/g algae, while the yield from biomass in the larger particle size range (295 μm ≤ x ≤ 425 μm) was 75.45 mg glucose/g algae. A similar trend was observed for bioethanol yield, with the highest yield of 0.47 g EtOH/g glucose obtained from biomass in the smallest particle size range. The results have shown that the microalgal biomass particle size has a significant effect on enzymatic hydrolysis and bioethanol yield.

  20. Does litter size variation affect models of terrestrial carnivore extinction risk and management?

    Directory of Open Access Journals (Sweden)

    Eleanor S Devenish-Nelson

    Full Text Available BACKGROUND: Individual variation in both survival and reproduction has the potential to influence extinction risk. Especially for rare or threatened species, reliable population models should adequately incorporate demographic uncertainty. Here, we focus on an important form of demographic stochasticity: variation in litter sizes. We use terrestrial carnivores as an example taxon, as they are frequently threatened or of economic importance. Since data on intraspecific litter size variation are often sparse, it is unclear what probability distribution should be used to describe the pattern of litter size variation for multiparous carnivores. METHODOLOGY/PRINCIPAL FINDINGS: We used litter size data on 32 terrestrial carnivore species to test the fit of 12 probability distributions. The influence of these distributions on quasi-extinction probabilities and the probability of successful disease control was then examined for three canid species - the island fox Urocyon littoralis, the red fox Vulpes vulpes, and the African wild dog Lycaon pictus. Best fitting probability distributions differed among the carnivores examined. However, the discretised normal distribution provided the best fit for the majority of species, because variation among litter-sizes was often small. Importantly, however, the outcomes of demographic models were generally robust to the distribution used. CONCLUSION/SIGNIFICANCE: These results provide reassurance for those using demographic modelling for the management of less studied carnivores in which litter size variation is estimated using data from species with similar reproductive attributes.

  1. Pupil constriction can alter the accuracy of dark room provocative test

    Institute of Scientific and Technical Information of China (English)

    WANG Bing-song; WANG Ning-li; Nathan Cong-don; LEI Kun; Baskaran Mani

    2009-01-01

    Background Primary angle-closure glaucoma(PACG)is a major cause of visual morbidity in East Asia.Dark-room provocative test(DRPT)has been used to determine which narrow angles have the risk to develop angle closure.However,the accuracy of DRPT might be altered because that after emerging from the dark room,the configuration of the angle is affected by the light of the slit-lamp and the appositionally closed angle reopens.The aim of this study was to examine the pupillary diameter in different light conditions and use it as a parameter to assess the accuracy of dark-room provocative test.Methods Patients with suspected primary angle-closure glaucoma undergoing DRPT were recruited.The anterior chamber angle was examined by anterior segment optical coherence tomography under the following conditions:(1)in standard room illumination;(2)after short-term dark-adaptation and(3)after DRPT.Mean values of pupil size and numbers of appositionally closed angle under different conditions were compared.Results A total of 47 eyes of 47 patients were analyzed.The pupil size after DRPT was smaller than that after short-term dark-adaptation(P<0.001)and smaller than that in standard room illumination(P=0.026).The numbers of appositionally closed angles after short-term dark-adaptation were significantly larger than those after DRPT(P<0.001).There was no significant difference between the numbers of appositionally closed angles in standard room illumination and after DRPT(P=0.157).Conclusions Constriction of pupil size immediately after prolonged dark room provocative test may lead to change in the angle configuration,which may lead to false negative results.We suggest a modified protocol of recording intraocular pressure immediately after DRPT and performing gonioscopy following short-term dark adaptation to improve the accuracy of angle closure assessment.

  2. Manipulation of Auxin Response Factor 19 affects seed size in the woody perennial Jatropha curcas

    Science.gov (United States)

    Sun, Yanwei; Wang, Chunming; Wang, Ning; Jiang, Xiyuan; Mao, Huizhu; Zhu, Changxiang; Wen, Fujiang; Wang, Xianghua; Lu, Zhijun; Yue, Genhua; Xu, Zengfu; Ye, Jian

    2017-01-01

    Seed size is a major determinant of seed yield but few is known about the genetics controlling of seed size in plants. Phytohormones cytokinin and brassinosteroid were known to be involved in the regulation of herbaceous plant seed development. Here we identified a homolog of Auxin Response Factor 19 (JcARF19) from a woody plant Jatropha curcas and genetically demonstrated its functions in controlling seed size and seed yield. Through Virus Induced Gene Silencing (VIGS), we found that JcARF19 was a positive upstream modulator in auxin signaling and may control plant organ size in J. curcas. Importantly, transgenic overexpression of JcARF19 significantly increased seed size and seed yield in plants Arabidopsis thaliana and J. curcas, indicating the importance of auxin pathway in seed yield controlling in dicot plants. Transcripts analysis indicated that ectopic expression of JcARF19 in J. curcas upregulated auxin responsive genes encoding essential regulators in cell differentiation and cytoskeletal dynamics of seed development. Our data suggested the potential of improving seed traits by precisely engineering auxin signaling in woody perennial plants. PMID:28102350

  3. Sexual selection affects the sizes of the mammalian prostate gland and seminal vesicles

    Institute of Scientific and Technical Information of China (English)

    Matthew J.ANDERSON; Alan F.DIXSON

    2009-01-01

    The accessory reproductive glands of male mammals contribute the bulk of the secretions in which spermatozoa are transported to the female tract during copulation. Despite their morphological diversity,and the chemical complexity of their products,little is known about the possible effects of sexual selection upon these glands in mammals. Here we consider the seminal vesicles and prostate glands in a sample of 89 species and 60 genera representing 8 Orders of mammals. The sizes of the accessory glands are analysed in relation to body weight and testes weight. Both the seminal vesicles size and prostate size (corrected for body weight) correlate positively with relative testes size in this sample; this finding remains highly significant after application of procedures to correct for possible phylogenetic biases in the data set. The accessory reproductive glands are also significantly larger in those mammals which have large relative testes sizes,and in which the likelihood of sperm competition is greatest. These results support the hypothesis that sexual selection has played an important role in the evolution of the mammalian prostate gland and seminal vesicles.

  4. Nectar foraging behaviour is affected by ant body size in Camponotus mus.

    Science.gov (United States)

    Medan, Violeta; Josens, Roxana B

    2005-08-01

    The nectivorous ant Camponotus mus shows a broad size variation within the worker caste. Large ants can ingest faster and larger loads than small ones. Differences in physiological abilities in fluid ingestion due to the insect size could be related to differences in decision-making according to ant size during nectar foraging. Sucrose solutions of different levels of sugar concentration (30% or 60%w/w), viscosity (high or low) or flow rate (ad libitum or 1microl/min) were offered in combination to analyse the behavioural responses to each of these properties separately. Differences were found depending on ant body size and the property compared. A regulated flow produced smaller crop loads for medium and large ants compared to the same solution given ad libitum. All foragers remained longer times feeding at the regulated flow source but larger ants often made longer interruptions. When sugar concentration was constant but viscosity was high, only large ants increased feeding time. Constant viscosity with different sugar concentration determined longer feeding time and bigger loads for the most concentrated solution for small but not for large ants. Small ants reached similar crop loads in a variety of conditions while large ants did not. These differences could be evidence of a possible specialization for nectar foraging based on ant body size.

  5. How molecular internal-geometric parameters affect PB-PEO polymersome size in aqueous solution

    DEFF Research Database (Denmark)

    Habel, Joachim Erich Otto; Ogbonna, Anayo; Larsen, Nanna

    2016-01-01

    is the ratio between the hydrophilic block volume and the entire diblock volume. However the polymersome size distribution also depends on molecular weight (Mn) and in order to gain insight on how f and Mn together determine polymersome size, we prepared PB-PEO diblock copolymers with different block lengths...... and analyzed vesicle morphology via Dynamic light scattering (DLS) and Freeze-fracture transmission electron microscopy (FF-TEM). We found three main regimes: high f / low Mn with polymersomes of mixed diameter, high f / high Mn with mainly large polymersomes and low f, with mainly small polymersomes...

  6. Perturbation of nucleo-cytoplasmic transport affects size of nucleus and nucleolus in human cells.

    Science.gov (United States)

    Ganguly, Abira; Bhattacharjee, Chumki; Bhave, Madhura; Kailaje, Vaishali; Jain, Bhawik K; Sengupta, Isha; Rangarajan, Annapoorni; Bhattacharyya, Dibyendu

    2016-03-01

    Size regulation of human cell nucleus and nucleolus are poorly understood subjects. 3D reconstruction of live image shows that the karyoplasmic ratio (KR) increases by 30-80% in transformed cell lines compared to their immortalized counterpart. The attenuation of nucleo-cytoplasmic transport causes the KR value to increase by 30-50% in immortalized cell lines. Nucleolus volumes are significantly increased in transformed cell lines and the attenuation of nucleo-cytoplasmic transport causes a significant increase in the nucleolus volume of immortalized cell lines. A cytosol and nuclear fraction swapping experiment emphasizes the potential role of unknown cytosolic factors in nuclear and nucleolar size regulation.

  7. The Mind-Writing Pupil: A Human-Computer Interface Based on Decoding of Covert Attention through Pupillometry.

    Directory of Open Access Journals (Sweden)

    Sebastiaan Mathôt

    Full Text Available We present a new human-computer interface that is based on decoding of attention through pupillometry. Our method builds on the recent finding that covert visual attention affects the pupillary light response: Your pupil constricts when you covertly (without looking at it attend to a bright, compared to a dark, stimulus. In our method, participants covertly attend to one of several letters with oscillating brightness. Pupil size reflects the brightness of the selected letter, which allows us-with high accuracy and in real time-to determine which letter the participant intends to select. The performance of our method is comparable to the best covert-attention brain-computer interfaces to date, and has several advantages: no movement other than pupil-size change is required; no physical contact is required (i.e. no electrodes; it is easy to use; and it is reliable. Potential applications include: communication with totally locked-in patients, training of sustained attention, and ultra-secure password input.

  8. The Mind-Writing Pupil: A Human-Computer Interface Based on Decoding of Covert Attention through Pupillometry.

    Science.gov (United States)

    Mathôt, Sebastiaan; Melmi, Jean-Baptiste; van der Linden, Lotje; Van der Stigchel, Stefan

    2016-01-01

    We present a new human-computer interface that is based on decoding of attention through pupillometry. Our method builds on the recent finding that covert visual attention affects the pupillary light response: Your pupil constricts when you covertly (without looking at it) attend to a bright, compared to a dark, stimulus. In our method, participants covertly attend to one of several letters with oscillating brightness. Pupil size reflects the brightness of the selected letter, which allows us-with high accuracy and in real time-to determine which letter the participant intends to select. The performance of our method is comparable to the best covert-attention brain-computer interfaces to date, and has several advantages: no movement other than pupil-size change is required; no physical contact is required (i.e. no electrodes); it is easy to use; and it is reliable. Potential applications include: communication with totally locked-in patients, training of sustained attention, and ultra-secure password input.

  9. Pupil-Linked Arousal Determines Variability in Perceptual Decision Making: e1003854

    National Research Council Canada - National Science Library

    Peter R Murphy; Joachim Vandekerckhove; Sander Nieuwenhuis

    2014-01-01

    .... We measured pupil size, a highly sensitive index of arousal, while human subjects performed a motion-discrimination task, and decomposed task behavior into latent decision making parameters using...

  10. Factors Affecting Teachers' Adoption of Technology in Classrooms: Does School Size Matter?

    Science.gov (United States)

    Wu, Hsin-Kai; Hsu, Ying-Shao; Hwang, Fu-Kwun

    2008-01-01

    Researchers in educational technology have searched for factors to explain teachers' acceptance and resistance to using technology for instruction. Among the many identified factors, however, organizational and school factors have not yet been explored and discussed. This study investigates the effects of school size on science and mathematics…

  11. Foraging mode affects the evolution of egg size in generalist predators embedded in complex food webs.

    Science.gov (United States)

    Verdeny-Vilalta, O; Fox, C W; Wise, D H; Moya-Laraño, J

    2015-06-01

    Ecological networks incorporate myriad biotic interactions that determine the selection pressures experienced by the embedded populations. We argue that within food webs, the negative scaling of abundance with body mass and foraging theory predict that the selective advantages of larger egg size should be smaller for sit-and-wait than active-hunting generalist predators, leading to the evolution of a difference in egg size between them. Because body mass usually scales negatively with predator abundance and constrains predation rate, slightly increasing egg mass should simultaneously allow offspring to feed on more prey and escape from more predators. However, the benefits of larger offspring would be relatively smaller for sit-and-wait predators because (i) due to their lower mobility, encounters with other predators are less common, and (ii) they usually employ a set of alternative hunting strategies that help to subdue relatively larger prey. On the other hand, for active predators, which need to confront prey as they find them, body-size differences may be more important in subduing prey. This difference in benefits should lead to the evolution of larger egg sizes in active-hunting relative to sit-and-wait predators. This prediction was confirmed by a phylogenetically controlled analysis of 268 spider species, supporting the view that the structure of ecological networks may serve to predict relevant selective pressures acting on key life history traits.

  12. Why does offspring size affect performance? Integrating metabolic scaling with life-history theory.

    Science.gov (United States)

    Pettersen, Amanda K; White, Craig R; Marshall, Dustin J

    2015-11-22

    Within species, larger offspring typically outperform smaller offspring. While the relationship between offspring size and performance is ubiquitous, the cause of this relationship remains elusive. By linking metabolic and life-history theory, we provide a general explanation for why larger offspring perform better than smaller offspring. Using high-throughput respirometry arrays, we link metabolic rate to offspring size in two species of marine bryozoan. We found that metabolism scales allometrically with offspring size in both species: while larger offspring use absolutely more energy than smaller offspring, larger offspring use proportionally less of their maternally derived energy throughout the dependent, non-feeding phase. The increased metabolic efficiency of larger offspring while dependent on maternal investment may explain offspring size effects-larger offspring reach nutritional independence (feed for themselves) with a higher proportion of energy relative to structure than smaller offspring. These findings offer a potentially universal explanation for why larger offspring tend to perform better than smaller offspring but studies on other taxa are needed.

  13. How the Assumed Size Distribution of Dust Minerals Affects the Predicted Ice Forming Nuclei

    Science.gov (United States)

    Perlwitz, Jan P.; Fridlind, Ann M.; Garcia-Pando, Carlos Perez; Miller, Ron L.; Knopf, Daniel A.

    2015-01-01

    The formation of ice in clouds depends on the availability of ice forming nuclei (IFN). Dust aerosol particles are considered the most important source of IFN at a global scale. Recent laboratory studies have demonstrated that the mineral feldspar provides the most efficient dust IFN for immersion freezing and together with kaolinite for deposition ice nucleation, and that the phyllosilicates illite and montmorillonite (a member of the smectite group) are of secondary importance.A few studies have applied global models that simulate mineral specific dust to predict the number and geographical distribution of IFN. These studies have been based on the simple assumption that the mineral composition of soil as provided in data sets from the literature translates directly into the mineral composition of the dust aerosols. However, these tables are based on measurements of wet-sieved soil where dust aggregates are destroyed to a large degree. In consequence, the size distribution of dust is shifted to smaller sizes, and phyllosilicates like illite, kaolinite, and smectite are only found in the size range 2 m. In contrast, in measurements of the mineral composition of dust aerosols, the largest mass fraction of these phyllosilicates is found in the size range 2 m as part of dust aggregates. Conversely, the mass fraction of feldspar is smaller in this size range, varying with the geographical location. This may have a significant effect on the predicted IFN number and its geographical distribution.An improved mineral specific dust aerosol module has been recently implemented in the NASA GISS Earth System ModelE2. The dust module takes into consideration the disaggregated state of wet-sieved soil, on which the tables of soil mineral fractions are based. To simulate the atmospheric cycle of the minerals, the mass size distribution of each mineral in aggregates that are emitted from undispersed parent soil is reconstructed. In the current study, we test the null

  14. Complex interactions among temporal variables affect the plasticity of clutch size in a multi-brooded bird.

    Science.gov (United States)

    Westneat, David F; Stewart, Ian R K; Hatch, Margret I

    2009-05-01

    Phenotypic plasticity is a widespread phenomenon and may have important influences on evolutionary processes. Multidimensional plasticity, in which multiple environmental variables affect a phenotype, is especially interesting if there are interactions among these variables. We used a long-term data set from House Sparrows (Passer domesticus), a multi-brooded passerine bird, to test several predictions from life-history theory regarding the shape of optimal reaction norms for clutch size. The best-fit model for variation in clutch size included three temporal variables (the order of attempt within a season, the date of those attempts, and the age of the female). Clutch size was also sensitive to the quadratics of date and female age, both of which had negative coefficients. Finally, we found that the relationship between date and clutch size became more negative as attempt order increased. These results suggest that female sparrows have a multidimensional reaction norm for clutch size that matches predictions of life-history theory but also implicates more complexity than can be captured by any single model. Analysis of the sources of variation in reaction norm height and slope was complicated by the additional environmental dimensions. We found significant individual variation in mean clutch size in all analyses, indicating that individuals differed in the height of their clutch size reaction norm. By contrast, we found no evidence of significant individual heterogeneity in the slopes of several dimensions. We assess the possible mechanisms producing this reaction norm and discuss their implications for understanding complex plasticity.

  15. Pupil Participation in Scottish Schools: How Far Have We Come?

    Science.gov (United States)

    Hulme, Moira; McKinney, Stephen; Hall, Stuart; Cross, Beth

    2011-01-01

    The United Nations Convention on the Rights of the Child (UN, 1989), which applies to all children under the age of 18, established the overarching principles guiding pupil participation. In most European states, signatories to the Convention have enacted policies to promote the voice of the child or young person in decisions that affect them. In…

  16. Investigation of Nonlinear Pupil Dynamics by Recurrence Quantification Analysis

    Directory of Open Access Journals (Sweden)

    L. Mesin

    2013-01-01

    Full Text Available Pupil is controlled by the autonomous nervous system (ANS. It shows complex movements and changes of size even in conditions of constant stimulation. The possibility of extracting information on ANS by processing data recorded during a short experiment using a low cost system for pupil investigation is studied. Moreover, the significance of nonlinear information contained in the pupillogram is investigated. We examined 13 healthy subjects in different stationary conditions, considering habitual dental occlusion (HDO as a weak stimulation of the ANS with respect to the maintenance of the rest position (RP of the jaw. Images of pupil captured by infrared cameras were processed to estimate position and size on each frame. From such time series, we extracted linear indexes (e.g., average size, average displacement, and spectral parameters and nonlinear information using recurrence quantification analysis (RQA. Data were classified using multilayer perceptrons and support vector machines trained using different sets of input indexes: the best performance in classification was obtained including nonlinear indexes in the input features. These results indicate that RQA nonlinear indexes provide additional information on pupil dynamics with respect to linear descriptors, allowing the discrimination of even a slight stimulation of the ANS. Their use in the investigation of pathology is suggested.

  17. Organoleptic and chemical quality of farmed meagre (Argyrosomus regius) as affected by size.

    Science.gov (United States)

    Giogios, Ioannis; Grigorakis, Kriton; Kalogeropoulos, Nick

    2013-12-01

    Two fish groups differing in size (average weighing 830±220 and 1600±350 g, respectively) were evaluated for their sensory, somatometric and chemical quality characteristics. No differences were found in the yields and fillet proximate composition of the two groups. Although taste panels indicated high acceptability for both groups, the large fish received significantly better hedonic rates for their overall acceptance. Differences were also observed in the fatty acid profiles of the two groups with the large fish having significantly higher 18:2n-6 and total n-6 contents. Their volatile compounds also differed, with small fish containing higher total amount, as well as more total aldehydes, furans and pyrazines. All these findings indicate size-dependent quality alterations, but also sufficient quality for small fish to be commercialised. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Does size and buoyancy affect the long-distance transport of floating debris?

    Science.gov (United States)

    Ryan, Peter G.

    2015-08-01

    Floating persistent debris, primarily made from plastic, disperses long distances from source areas and accumulates in oceanic gyres. However, biofouling can increase the density of debris items to the point where they sink. Buoyancy is related to item volume, whereas fouling is related to surface area, so small items (which have high surface area to volume ratios) should start to sink sooner than large items. Empirical observations off South Africa support this prediction: moving offshore from coastal source areas there is an increase in the size of floating debris, an increase in the proportion of highly buoyant items (e.g. sealed bottles, floats and foamed plastics), and a decrease in the proportion of thin items such as plastic bags and flexible packaging which have high surface area to volume ratios. Size-specific sedimentation rates may be one reason for the apparent paucity of small plastic items floating in the world’s oceans.

  19. Orthographic Consistency Affects Spoken Word Recognition at Different Grain-Sizes

    Science.gov (United States)

    Dich, Nadya

    2014-01-01

    A number of previous studies found that the consistency of sound-to-spelling mappings (feedback consistency) affects spoken word recognition. In auditory lexical decision experiments, words that can only be spelled one way are recognized faster than words with multiple potential spellings. Previous studies demonstrated this by manipulating…

  20. Orthographic Consistency Affects Spoken Word Recognition at Different Grain-Sizes

    Science.gov (United States)

    Dich, Nadya

    2014-01-01

    A number of previous studies found that the consistency of sound-to-spelling mappings (feedback consistency) affects spoken word recognition. In auditory lexical decision experiments, words that can only be spelled one way are recognized faster than words with multiple potential spellings. Previous studies demonstrated this by manipulating…

  1. Indoor environment and pupils' health in primary schools

    DEFF Research Database (Denmark)

    van Dijken, F.; van Bronswijk, J.E.M.H.; Sundell, Jan

    2006-01-01

    the associations between indoor environmental quality in Dutch schools and pupils' health, also taking into account the children's home environment and personal factors. A cross-sectional study was performed in 11 classrooms in 11 different schools in the Netherlands. The study included exposure measurements......Dutch children are legally bound to spend 15% of their time in a school setting. The indoor environment in Dutch primary schools is known to be substandard. However, it is unclear to what extent the health of pupils is affected by the indoor school environment. The paper aims to assess......, building inspections, and a questionnaire survey on pupils' health and domestic exposure. Principal Component Analysis (PCA) and non-parametric tests were performed to assess relationships. None of the schools complied with all indoor environmental quality standards. The importance of both the school...

  2. Does Cation Size Affect Occupancy and Electrostatic Screening of the Nucleic Acid Ion Atmosphere?

    Science.gov (United States)

    Gebala, Magdalena; Bonilla, Steve; Bisaria, Namita; Herschlag, Daniel

    2016-08-31

    Electrostatics are central to all aspects of nucleic acid behavior, including their folding, condensation, and binding to other molecules, and the energetics of these processes are profoundly influenced by the ion atmosphere that surrounds nucleic acids. Given the highly complex and dynamic nature of the ion atmosphere, understanding its properties and effects will require synergy between computational modeling and experiment. Prior computational models and experiments suggest that cation occupancy in the ion atmosphere depends on the size of the cation. However, the computational models have not been independently tested, and the experimentally observed effects were small. Here, we evaluate a computational model of ion size effects by experimentally testing a blind prediction made from that model, and we present additional experimental results that extend our understanding of the ion atmosphere. Giambasu et al. developed and implemented a three-dimensional reference interaction site (3D-RISM) model for monovalent cations surrounding DNA and RNA helices, and this model predicts that Na(+) would outcompete Cs(+) by 1.8-2.1-fold; i.e., with Cs(+) in 2-fold excess of Na(+) the ion atmosphere would contain an equal number of each cation (Nucleic Acids Res. 2015, 43, 8405). However, our ion counting experiments indicate that there is no significant preference for Na(+) over Cs(+). There is an ∼25% preferential occupancy of Li(+) over larger cations in the ion atmosphere but, counter to general expectations from existing models, no size dependence for the other alkali metal ions. Further, we followed the folding of the P4-P6 RNA and showed that differences in folding with different alkali metal ions observed at high concentration arise from cation-anion interactions and not cation size effects. Overall, our results provide a critical test of a computational prediction, fundamental information about ion atmosphere properties, and parameters that will aid in the

  3. Reduced Particle size of plant material does not stimulate decomposition but affects the microbivorous microfauna

    DEFF Research Database (Denmark)

    Vestergaard, Peter; Rønn, Regin; Christensen, Søren

    2001-01-01

    in soils amended with the large pieces on nine out of 10 occasions. Microbial biomass measured as SIR was significantly higher in soils with maize than in those amended with barley, but no effect of particle size was observed (three-way ANOVA, P... material, but significantly higher numbers were found in soil with finely-ground maize than in soil with large pieces (two-way ANOVA, P... barley (three-way ANOVA, P

  4. Microclimatic Divergence in a Mediterranean Canyon Affects Richness, Composition, and Body Size in Saproxylic Beetle Assemblages.

    Science.gov (United States)

    Buse, Jörn; Fassbender, Samuel; Entling, Martin H; Pavlicek, Tomas

    2015-01-01

    Large valleys with opposing slopes may act as a model system with which the effects of strong climatic gradients on biodiversity can be evaluated. The advantage of such comparisons is that the impact of a change of climate can be studied on the same species pool without the need to consider regional differences. The aim of this study was to compare the assemblage of saproxylic beetles on such opposing slopes at Lower Nahal Oren, Mt. Carmel, Israel (also known as "Evolution Canyon") with a 200-800% higher solar radiation on the south-facing (SFS) compared to the north-facing slope (NFS). We tested specific hypotheses of species richness patterns, assemblage structure, and body size resulting from interslope differences in microclimate. Fifteen flight-interception traps per slope were distributed over three elevation levels ranging from 50 to 100 m a.s.l. Richness of saproxylic beetles was on average 34% higher on the SFS compared with the NFS, with no detected influence of elevation levels. Both assemblage structure and average body size were determined by slope aspect, with more small-bodied beetles found on the SFS. Both the increase in species richness and the higher prevalence of small species on the SFS reflect ecological rules present on larger spatial grain (species-energy hypothesis and community body size shift hypothesis), and both can be explained by the metabolic theory of ecology. This is encouraging for the complementary use of micro- and macroclimatic gradients to study impacts of climate warming on biodiversity.

  5. The Creation of Small and Medium-Sized Sport Enterprises and the Environmental Factors Affecting It

    Directory of Open Access Journals (Sweden)

    Seyed Morteza Azimzadeh

    2013-05-01

    Full Text Available Small and medium-sized enterprises are very basic solutions for the development of a country; therefore, it is important to understand the factors involved in their creation. Hence, this study sought to examine the relationship between environmental factors and creation of Small and medium-sized sport enterprises. The research population was small and medium-sized sport enterprises (1500 companies; their owners / managers were selected as the research sample (n = 258 by simple random sampling. Data were gathered using environmental factors (α=0.77 and enterprises creation qualification (α=0.81 questionnaires. Descriptive and inferential statistics (Pearson correlation coefficient, Kolmogrof - Smirnov test, and multivariate regression analysis with SPSS16 software was used for data analysis. The results showed that in addition to positive and significant relationship with business, environmental factors could predict 6% of the creation variance; Also, except for the political dimension, all environmental aspects established a significant relationship with enterprise creation( p<0.01. Regression analysis showed that of environmental dimensions, economics and technology dimensions could explain 7 percent of Sports enterprise creation variance. According to path analysis method, this prediction ability is presented in a model. The findings suggested a diminished role of environment and its dimensions in explaining the process of SMEs creation.

  6. Acute sleep deprivation increases portion size and affects food choice in young men.

    Science.gov (United States)

    Hogenkamp, Pleunie S; Nilsson, Emil; Nilsson, Victor C; Chapman, Colin D; Vogel, Heike; Lundberg, Lina S; Zarei, Sanaz; Cedernaes, Jonathan; Rångtell, Frida H; Broman, Jan-Erik; Dickson, Suzanne L; Brunstrom, Jeffrey M; Benedict, Christian; Schiöth, Helgi B

    2013-09-01

    Acute sleep loss increases food intake in adults. However, little is known about the influence of acute sleep loss on portion size choice, and whether this depends on both hunger state and the type of food (snack or meal item) offered to an individual. The aim of the current study was to compare portion size choice after a night of sleep and a period of nocturnal wakefulness (a condition experienced by night-shift workers, e.g. physicians and nurses). Sixteen men (age: 23 ± 0.9 years, BMI: 23.6 ± 0.6 kg/m(2)) participated in a randomized within-subject design with two conditions, 8-h of sleep and total sleep deprivation (TSD). In the morning following sleep interventions, portion size, comprising meal and snack items, was measured using a computer-based task, in both fasted and sated state. In addition, hunger as well as plasma levels of ghrelin were measured. In the morning after TSD, subjects had increased plasma ghrelin levels (13%, p=0.04), and chose larger portions (14%, p=0.02), irrespective of the type of food, as compared to the sleep condition. Self-reported hunger was also enhanced (pchoice after sleep loss depend on both an individual's hunger status, and the type of food offered. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Temperature affects the size-structure of phytoplankton communities in the ocean

    KAUST Repository

    López-Urrutia, Ángel

    2015-03-05

    The strong inverse correlation between resource availability and temperature in the ocean poses a challenge to determine the relative effect of these two variables on the size-structure of natural phytoplankton communities. Maranon et al (2012) compiled a dataset of concurrent temperature and resource level proxies that they claim disentangled the effect of temperature from that of resource supply. They concluded that the hypothesis that temperature per se plays a direct role in controlling phytoplankton size structure should be rejected. But our reanalysis of their data reaches a very different conclusion and suggests that they failed to separate the effects of temperature from the effects of resources. Although we obviously concur with Maranon et al (2012) in the long-known predominance of small phytoplankton cells under oligotrophic conditions, from our point of view this should not deter us from considering temperature as an important explanatory variable at a global scale since we show that, for the vast oligotrophic areas of the world\\'s oceans where chlorophyll concentrations are below <1 g L-1 temperature explains a high proportion of the variability in the size distribution of phytoplankton communities, a variability that can not be explained on the basis of the resource level proxies advocated by Maranon et al. (2012).

  8. Does the "Pupil Enterprise Programme" Influence Grades among Pupils with Special Needs?

    Science.gov (United States)

    Johansen, Vegard; Somby, Hege M.

    2016-01-01

    This paper asks whether the Pupil Enterprise Programme (PEP) is a suitable working method for improving academic performance among pupils with special needs. Overall, 20% of pupils participate in PEP at some point during lower secondary school. Results from multilevel regression modelling indicate that pupils with special needs who have…

  9. Relationships among Teacher Personality, Pupil Control Attidues, and Pupil Control Behavior.

    Science.gov (United States)

    Bush, Doris W.

    This research examined the relationships among three variables--teacher personality, teacher pupil control attitudes, and teacher pupil control behavior--to determine whether teacher personality or pupil control attitudes were the better predictor of pupil control behavior. Subjects were 102 junior high school teachers. The major finding of the…

  10. The "subjective" pupil old/new effect: is the truth plain to see?

    Science.gov (United States)

    Montefinese, Maria; Ambrosini, Ettore; Fairfield, Beth; Mammarella, Nicola

    2013-07-01

    Human memory is an imperfect process, prone to distortion and errors that range from minor disturbances to major errors that can have serious consequences on everyday life. In this study, we investigated false remembering of manipulatory verbs using an explicit recognition task and pupillometry. Our results replicated the "classical" pupil old/new effect as well as data in false remembering literature that show how items must be recognize as old in order for the pupil size to increase (e.g., "subjective" pupil old/new effect), even though these items do not necessarily have to be truly old. These findings support the strength-of-memory trace account that affirms that pupil dilation is related to experience rather than to the accuracy of recognition. Moreover, behavioral results showed higher rates of true and false recognitions for manipulatory verbs and a consequent larger pupil diameter, supporting the embodied view of language.

  11. Sample Size Calculation: Inaccurate A Priori Assumptions for Nuisance Parameters Can Greatly Affect the Power of a Randomized Controlled Trial.

    Directory of Open Access Journals (Sweden)

    Elsa Tavernier

    Full Text Available We aimed to examine the extent to which inaccurate assumptions for nuisance parameters used to calculate sample size can affect the power of a randomized controlled trial (RCT. In a simulation study, we separately considered an RCT with continuous, dichotomous or time-to-event outcomes, with associated nuisance parameters of standard deviation, success rate in the control group and survival rate in the control group at some time point, respectively. For each type of outcome, we calculated a required sample size N for a hypothesized treatment effect, an assumed nuisance parameter and a nominal power of 80%. We then assumed a nuisance parameter associated with a relative error at the design stage. For each type of outcome, we randomly drew 10,000 relative errors of the associated nuisance parameter (from empirical distributions derived from a previously published review. Then, retro-fitting the sample size formula, we derived, for the pre-calculated sample size N, the real power of the RCT, taking into account the relative error for the nuisance parameter. In total, 23%, 0% and 18% of RCTs with continuous, binary and time-to-event outcomes, respectively, were underpowered (i.e., the real power was 90%. Even with proper calculation of sample size, a substantial number of trials are underpowered or overpowered because of imprecise knowledge of nuisance parameters. Such findings raise questions about how sample size for RCTs should be determined.

  12. Microclimatic Divergence in a Mediterranean Canyon Affects Richness, Composition, and Body Size in Saproxylic Beetle Assemblages.

    Directory of Open Access Journals (Sweden)

    Jörn Buse

    Full Text Available Large valleys with opposing slopes may act as a model system with which the effects of strong climatic gradients on biodiversity can be evaluated. The advantage of such comparisons is that the impact of a change of climate can be studied on the same species pool without the need to consider regional differences. The aim of this study was to compare the assemblage of saproxylic beetles on such opposing slopes at Lower Nahal Oren, Mt. Carmel, Israel (also known as "Evolution Canyon" with a 200-800% higher solar radiation on the south-facing (SFS compared to the north-facing slope (NFS. We tested specific hypotheses of species richness patterns, assemblage structure, and body size resulting from interslope differences in microclimate. Fifteen flight-interception traps per slope were distributed over three elevation levels ranging from 50 to 100 m a.s.l. Richness of saproxylic beetles was on average 34% higher on the SFS compared with the NFS, with no detected influence of elevation levels. Both assemblage structure and average body size were determined by slope aspect, with more small-bodied beetles found on the SFS. Both the increase in species richness and the higher prevalence of small species on the SFS reflect ecological rules present on larger spatial grain (species-energy hypothesis and community body size shift hypothesis, and both can be explained by the metabolic theory of ecology. This is encouraging for the complementary use of micro- and macroclimatic gradients to study impacts of climate warming on biodiversity.

  13. Smaller is better: drift in gaze measurements due to pupil dynamics.

    Science.gov (United States)

    Drewes, Jan; Zhu, Weina; Hu, Yingzhou; Hu, Xintian

    2014-01-01

    Camera-based eye trackers are the mainstay of eye movement research and countless practical applications of eye tracking. Recently, a significant impact of changes in pupil size on gaze position as measured by camera-based eye trackers has been reported. In an attempt to improve the understanding of the magnitude and population-wise distribution of the pupil-size dependent shift in reported gaze position, we present the first collection of binocular pupil drift measurements recorded from 39 subjects. The pupil-size dependent shift varied greatly between subjects (from 0.3 to 5.2 deg of deviation, mean 2.6 deg), but also between the eyes of individual subjects (0.1 to 3.0 deg difference, mean difference 1.0 deg). We observed a wide range of drift direction, mostly downward and nasal. We demonstrate two methods to partially compensate the pupil-based shift using separate calibrations in pupil-constricted and pupil-dilated conditions, and evaluate an improved method of compensation based on individual look-up-tables, achieving up to 74% of compensation.

  14. Rheological quality of pearl millet porridge as affected by grits size.

    Science.gov (United States)

    Yadav, Deep N; Chhikara, Navnidhi; Anand, Tanupriya; Sharma, Monika; Singh, Ashish K

    2014-09-01

    Study was conducted to optimize pearl millet grits size for the preparation of acceptable porridge with skimmed milk powder (SMP). Pearl millet porridge was prepared with different grits size (1.410, 0.841, 0.595, and 0.420 mm). A positive (r = 0.904) correlation was observed between water absorption index and grits size. Porridge showed shear thinning behavior as, initially shear stress increased with increase in shear rate and later on decreased. Porridge prepared with larger grits (1.410 mm) exhibited higher firmness (38.4 ± 1.27 N) and viscosity (446 ± 3.9 cP), whereas smaller grits (0.420 mm) resulted in less viscous (118.8 ± 1.74 cP) and firm (20.4 ± 1.85 N) porridge. The medium grits (0.841 mm) produced porridge with acceptable firmness (30.7 ± 1.56 N) and viscosity (298.1 ± 8.81 cP) with moderate (6.0 ± 0.10) acceptability. To improve sensory quality of porridge (grits size 0.841 mm); skimmed milk powder at different levels (0, 5, 10 and 15 %) was added and its effect on various quality parameters was studied. SMP addition significantly (P ≤ 0.05) modified the gelatinization and gelling behavior of grits and decreased (P ≤ 0.05) all the pasting characteristics except pasting temperature, which increased from 77.1 ± 1.85 to 85.9 ± 3.46 °C. The peak (499 ± 6.6 cP) and final viscosity (450 ± 11.9 cP) of porridge (0.841 mm) prepared with 15 % SMP are quite similar. Hence, it maintains viscosity on cooling, similar to maximum viscosity attained during cooking. Keeping in view the rheological, firmness and sensory quality, 0.841 mm grits of pearl millet with 15 % SMP was found optimum for preparation of acceptable porridge.

  15. Is Chemistry Attractive for Pupils? Czech Pupils' Perception of Chemistry

    Science.gov (United States)

    Kubiatko, Milan

    2015-01-01

    Chemistry is an important subject due to understanding the composition and structure of the things around us. The main aim of the study was to find out the perception of chemistry by lower secondary school pupils. The partial aims were to find out the influence of gender, year of study and favorite subject on the perception of chemistry. The…

  16. Putting Up a Big Front: Car Design and Size Affect Road-Crossing Behaviour.

    Directory of Open Access Journals (Sweden)

    Wilhelm K Klatt

    Full Text Available Previous research suggests that people tend to see faces in car fronts and that they attribute personality characteristics to car faces. In the present study we investigated whether car design influences pedestrian road-crossing behaviour. An immersive virtual reality environment with a zebra crossing scenario was used to determine a whether the minimum accepted distance for crossing the street is larger for cars with a dominant appearance than for cars with a friendly appearance and b whether the speed of dominant-looking cars is overestimated as compared to friendly-looking cars. Participants completed both tasks while either standing on the pavement or on the centre island. We found that people started to cross the road later in front of friendly-looking low-power cars compared to dominant-looking high-power cars, but only if the cars were relatively large in size. For small cars we found no effect of power. The speed of smaller cars was estimated to be higher compared to large cars (size-speed bias. Furthermore, there was an effect of starting position: From the centre island, participants entered the road significantly later (i. e. closer to the approaching car and left the road later than when starting from the pavement. Similarly, the speed of the cars was estimated significantly lower when standing on the centre island compared to the pavement. To our knowledge, this is the first study to show that car fronts elicit responses on a behavioural level.

  17. Putting Up a Big Front: Car Design and Size Affect Road-Crossing Behaviour.

    Science.gov (United States)

    Klatt, Wilhelm K; Chesham, Alvin; Lobmaier, Janek S

    2016-01-01

    Previous research suggests that people tend to see faces in car fronts and that they attribute personality characteristics to car faces. In the present study we investigated whether car design influences pedestrian road-crossing behaviour. An immersive virtual reality environment with a zebra crossing scenario was used to determine a) whether the minimum accepted distance for crossing the street is larger for cars with a dominant appearance than for cars with a friendly appearance and b) whether the speed of dominant-looking cars is overestimated as compared to friendly-looking cars. Participants completed both tasks while either standing on the pavement or on the centre island. We found that people started to cross the road later in front of friendly-looking low-power cars compared to dominant-looking high-power cars, but only if the cars were relatively large in size. For small cars we found no effect of power. The speed of smaller cars was estimated to be higher compared to large cars (size-speed bias). Furthermore, there was an effect of starting position: From the centre island, participants entered the road significantly later (i. e. closer to the approaching car) and left the road later than when starting from the pavement. Similarly, the speed of the cars was estimated significantly lower when standing on the centre island compared to the pavement. To our knowledge, this is the first study to show that car fronts elicit responses on a behavioural level.

  18. Size of food bowl and scoop affects amount of food owners feed their dogs.

    Science.gov (United States)

    Murphy, M; Lusby, A L; Bartges, J W; Kirk, C A

    2012-04-01

    The incidence of canine obesity appears to be increasing dramatically and understanding factors impacting the amount of food pet owners provide their dogs may improve weight management. Human research has shown the size of food bowls, plates and utensils can significantly impact the amount of food portioned and consumed. This effect can be attributed to both the Delboeuf optical illusion and the Ebbinghaus-Titchener size-contrast illusion. To investigate the existence of a similar effect with dog owners, 54 dogs and their owners were recruited for a four treatment randomized prospective trial. Owners scooped out a normal kibble-based meal using a small bowl and small scoop, small bowl and large scoop, large bowl and small scoop or a large bowl and large scoop. Each treatment was used once per owner over four visits. Repeated measures anova revealed the mean amount of food portioned using the small bowl and small scoop was significantly less than all other bowl and scoop combinations (150.7 g vs. 171.5 g vs. 172.7 g vs. 184.5 g, p 0.05). Owners were more likely to portion a larger amount of food with a large bowl and large scoop. Results are consistent with human data and emphasize the need for owners to use standard measuring cups. Results also suggest owner compliance during weight loss programs may be improved with smaller bowls and serving scoops. © 2011 Blackwell Verlag GmbH.

  19. Alterations in seed development gene expression affect size and oil content of Arabidopsis seeds.

    Science.gov (United States)

    Fatihi, Abdelhak; Zbierzak, Anna Maria; Dörmann, Peter

    2013-10-01

    Seed endosperm development in Arabidopsis (Arabidopsis thaliana) is under control of the polycomb group complex, which includes Fertilization Independent Endosperm (FIE). The polycomb group complex regulates downstream factors, e.g. Pheres1 (PHE1), by genomic imprinting. In heterozygous fie mutants, an endosperm develops in ovules carrying a maternal fie allele without fertilization, finally leading to abortion. Another endosperm development pathway depends on MINISEED3 (a WRKY10 transcription factor) and HAIKU2 (a leucine-rich repeat kinase). While the role of seed development genes in the embryo and endosperm establishment has been studied in detail, their impact on metabolism and oil accumulation remained unclear. Analysis of oil, protein, and sucrose accumulation in mutants and overexpression plants of the four seed development genes revealed that (1) seeds carrying a maternal fie allele accumulate low oil with an altered composition of triacylglycerol molecular species; (2) homozygous mutant seeds of phe1, mini3, and iku2, which are smaller, accumulate less oil and slightly less protein, and starch, which accumulates early during seed development, remains elevated in mutant seeds; (3) embryo-specific overexpression of FIE, PHE1, and MINI3 has no influence on seed size and weight, nor on oil, protein, or sucrose content; and (4) overexpression of IKU2 results in seeds with increased size and weight, and oil content of overexpressed IKU2 seeds is increased by 35%. Thus, IKU2 overexpression represents a novel strategy for the genetic manipulation of the oil content in seeds.

  20. Perceptions of portion size and energy content: implications for strategies to affect behaviour change.

    Science.gov (United States)

    Brindal, Emily; Wilson, Carlene; Mohr, Philip; Wittert, Gary

    2012-02-01

    To assess Australian consumers' perception of portion size of fast-food items and their ability to estimate energy content. Cross-sectional computer-based survey. Australia. Fast-food consumers (168 male, 324 female) were asked to recall the items eaten at the most recent visit to a fast-food restaurant, rate the prospective satiety and estimate the energy content of seven fast-food or 'standard' meals relative to a 9000 kJ Guideline Daily Amount. Nine dietitians also completed the energy estimation task. Ratings of prospective satiety generally aligned with the actual size of the meals and indicated that consumers perceived all meals to provide an adequate amount of food, although this differed by gender. The magnitude of the error in energy estimation by consumers was three to ten times that of the dietitians. In both males and females, the average error in energy estimation for the fast-food meals (females: mean 3911 (sd 1998) kJ; males: mean 3382 (sd 1957) kJ) was significantly (P fast-food items predicted actual energy intake from fast-food items (β = 0·16, P fast-food meals in fast-food consumers in Australia is poor. Awareness of dietary energy should be a focus of health promotion if nutrition information, in its current format, is going to alter behaviour.

  1. Understanding Pupils' Hiding Techniques in Physical Education

    Science.gov (United States)

    Lyngstad, Idar; Hagen, Per-Magnus; Aune, Ola

    2016-01-01

    Previous research shows that some pupils find physical education (PE) demanding and difficult. Some pupils use strategies to avoid participation in PE when it is demanding and difficult. The present study aims to illuminate and describe strategies used by pupils to avoid negative self-perception in difficult situations and activities in PE…

  2. The reconstruction of choice value in the brain: a look into the size of consideration sets and their affective consequences.

    Science.gov (United States)

    Kim, Hye-Young; Shin, Yeonsoon; Han, Sanghoon

    2014-04-01

    It has been proposed that choice utility exhibits an inverted U-shape as a function of the number of options in the choice set. However, most researchers have so far only focused on the "physically extant" number of options in the set while disregarding the more important psychological factor, the "subjective" number of options worth considering to choose-that is, the size of the consideration set. To explore this previously ignored aspect, we examined how variations in the size of a consideration set can produce different affective consequences after making choices and investigated the underlying neural mechanism using fMRI. After rating their preferences for art posters, participants made a choice from a presented set and then reported on their level of satisfaction with their choice and the level of difficulty experienced in choosing it. Our behavioral results demonstrated that enlarged assortment set can lead to greater choice satisfaction only when increases in both consideration set size and preference contrast are involved. Moreover, choice difficulty is determined based on the size of an individual's consideration set rather than on the size of the assortment set, and it decreases linearly as a function of the level of contrast among alternatives. The neuroimaging analysis of choice-making revealed that subjective consideration set size was encoded in the striatum, the dACC, and the insula. In addition, the striatum also represented variations in choice satisfaction resulting from alterations in the size of consideration sets, whereas a common neural specificity for choice difficulty and consideration set size was shown in the dACC. These results have theoretical and practical importance in that it is one of the first studies investigating the influence of the psychological attributes of choice sets on the value-based decision-making process.

  3. Unilateral Adie's tonic pupil and viral hepatitis: Report of two cases

    Directory of Open Access Journals (Sweden)

    Karadžić Jelena

    2015-01-01

    Full Text Available Introduction. Adie’s (tonic pupil is a neuro-ophthalmological disorder characterized by a tonically dilated pupil, which is unresponsive to light. It is caused by damage to postganglionic fibers of the parasympathetic innervation of the eye, usually by a viral or bacterial infection. Adie’s syndrome includes diminished deep tendon reflexes. Outline of Cases. We report data of a 59-year-old female with unequal pupil sizes. She complained of blurred vision and headache mainly while reading. She had a 35-year history of hepatitis B and liver cirrhosis. On exam, left pupil was mydriatic and there was no response to light and at slit lamp we saw segments of the sphincter constrict. We performed 0.125% pilocarpine test and there was a remarkable reduction of size in the left pupil. The second case is a 55-year-old female who was referred to the University Eye Clinic because of a headache and mydriatic left pupil. She had diabetes mellitus type 2, as well as hepatitis A virus 20 years earlier. On exam, the left pupil was mydriatic, with no response to light. Test with diluted pilocarpine was positive. Neurological examinations revealed no abnormality in either case so we excluded Adie’s syndrome. Conclusion. Adie’s tonic pupil is benign neuro-ophthalmological disorder of unknown etiology. Most patients commonly present no symptoms and anisocoria is noticed accidentally. Although the etiology is unknown, there are some conditions that cause tonic pupil. It may be a part of a syndrome in which tonic pupil is associated with absent deep tendon reflexes.

  4. Neural Correlates of Fast Pupil Dilation in Nonhuman Primates: Relation to Behavioral Performance and Cognitive Workload

    Science.gov (United States)

    Hampson, R.E.; Opris, Ioan; Deadwyler, S.A.

    2010-01-01

    Pupil dilation in humans has been previously shown to correlate with cognitive workload, whereby increased frequency of dilation is associated with increased degree of difficulty of a task. It has been suggested that frontal oculomotor brain areas control cognitively-related pupil dilations, but this has not been confirmed due to lack of animal models of cognitive workload and task-related pupil dilation. This is the first report of a wavelet analysis applied to continuous measures of pupil size used to detect the onset of abrupt pupil dilations and the frequency of those dilations in nonhuman primates (NHPs) performing a trial-unique delayed match to sample (DMS) task. An additional unique finding shows that electrophysiological recordings in the same animals revealed correlated firing of neurons in frontal cortex with different components of pupil dilation during task performance. It is further demonstrated that the frequency of fast pupil dilations (but not rate of eye movements) correlated with cognitive workload during task performance. Such correlations suggest that frontal neuron encoding of pupil dilation provides critical feedback to other brain areas involved in the processing of complex visual information. PMID:20226215

  5. Orthographic consistency affects spoken word recognition at different grain-sizes

    DEFF Research Database (Denmark)

    Dich, Nadya

    2014-01-01

    A number of previous studies found that the consistency of sound-to-spelling mappings (feedback consistency) affects spoken word recognition. In auditory lexical decision experiments, words that can only be spelled one way are recognized faster than words with multiple potential spellings. Previous...... studies demonstrated this by manipulating feedback consistency of rhymes. The present lexical decision study, done in English, manipulated the spelling of individual vowels within consistent rhymes. Participants recognized words with consistent rhymes where the vowel has the most typical spelling (e...... and spelling. The theoretical and methodological implications for future research in spoken word recognition are discussed....

  6. Interrill erosion, runoff and sediment size distribution as affected by slope steepness and antecedent moisture content

    Directory of Open Access Journals (Sweden)

    M. B. Defersha

    2010-08-01

    Full Text Available Soil erosion is a two-phase process consisting of the detachment of individual particles and their transport by erosive agents such as flowing water. The rate at which erosion occurs depends upon the individual as well as interactive effects of different parameters responsible for soil erosion. The study discusses results of a laboratory analysis and evaluates the effect of slope steepness and antecedent moisture content on sediment yield (wash and runoff rate. Interrill sediment yield, splash detachment, runoff, and sediment size distribution were measured in laboratory erosion pans under simulated total duration of 90 min. Rainfall intensity at 120 mm/hr, 70 mm/hr, and 55 mm/hr were applied sequentially at 9, 25, and 45% slope steepness for three soils (Alemaya Black soil, Regosols, and Cambisols varied from clay to sandy clay loam in texture with wet and dry antecedent water contents. As slope steepness increased from 9 to 25% splash increased for five treatments and decreased for the remaining treatment; washed sediment increased for all treatments. As slope increased from 25 to 45% splash decreased for five treatments but increased for one treatment, and washed sediment increased for three treatments but decreased for the other three treatments. Pre-wetting decreased splash detachment for all soil treatments and rate of reduction was high for the highly aggregated soil, Alemaya Black soil and low for the less aggregated soil Regosols. Splash sediment and sediment yield was not correlated. Change in splash with increase in slope steepness was also not correlated with change in sediment yield. Change in runoff rate with increase in slope steepness was correlated (r=0.66 with change in sediment yield. For Alemaya Black soil and Regosols, splashed sediment size distribution was correlated with washed sediment size distribution. Interrill erosion models that include runoff and rainfall intensity parameters were a better fit for these data

  7. The modelling of the influence of a corneal geometry on the pupil image of the human eye

    Science.gov (United States)

    Szczesna, D. H.; Kasprzak, H. T.

    2006-07-01

    In normal conditions, a pupil of the eye is observed through the optical system of the cornea. The cornea is the anterior surface of the eye and is the major refractive element of the human eye. The influence of the corneal shape should not be neglected in measurements of the pupil size. The purpose of this study was to estimate the influence of the corneal geometry, the diameter of the pupil and its position in the anterior chamber on the magnification and position of the image of the pupil. The numerical calculations presented in the paper assume infinitely thin cornea, and the corneal topography was approximated by the elongated ellipsoid. The ray tracing procedure was used in our numerical modelling. The magnification of the pupil image amounted to about 10% and increases with decrease of radius of curvature and eccentricity of the corneal profile and decreases for the largest pupil. The results show also that the pupil image is placed nearer the corneal apex than the real pupil. The image of the pupil is always blurred, which limits the sharp observation of the pupil.

  8. Does intruder group size and orientation affect flight initiation distance in birds?

    Directory of Open Access Journals (Sweden)

    Geist, C.

    2005-06-01

    Full Text Available Wildlife managers use flight initiation distance (FID, the distance animals flee an approaching predator, to determine set back distances to minimize human impacts on wildlife. FID is typically estimated by a single person; this study examined the effects of intruder number and orientation on FID. Three different group size treatments (solitary person, two people side-by-side, two people one-behind-the-other were applied to Pied Currawongs (Strepera graculina and to Crimson Rosellas (Platycerus elegans. Rosellas flushed at significantly greater distances when approached by two people compared to a single person. This effect was not seen in currawongs. Intruder orientation did not influence the FID of either species. Results suggest that intruder number should be better integrated into estimates of set back distance to manage human visitation around sensitive species.

  9. [Sizes of soil macropores and related main affecting factors on a vegetated basalt slope].

    Science.gov (United States)

    Guan, Qi; Xu, Ze-Min; Tian, Lin

    2013-10-01

    The landslide on vegetated slopes caused by extreme weather has being increased steadily, and the preferential flow in soil macropores plays an important role in the landslide. By using water breakthrough curve and Poiseuille equation, this paper estimated the radius range, amount, and average volume of soil macropores on a vegetated basalt slope of Maka Mountain, Southwest China, and analyzed the distribution of the soil macropores and the main affecting factors. In the study area, the radius of soil macropores ranged from 0.3 to 1.8 mm, mainly between 0.5 and 1.2 mm. The large-radius macropores (1.4-1.8 mm) were lesser, while the small-radius macropores (< 1.4 mm) were more. With the development of soil profile, soil macropores were more in upper layers and lesser in deeper layers. The average volume of the macropores contributed 84.7% to the variance of steady effluent rate. Among the factors affecting the average volume of the large macropores, vegetations root mass had a linear relationship, with the correlation coefficient being 0.70, and soil organic matter content also had a linear relationship, with the correlation coefficient being 0.64.

  10. Does school size affect interest for purchasing local foods in the midwest?

    Science.gov (United States)

    Smith, Sylvia; Wleklinski, Danielle; Roth, Sara Long; Tragoudas, Ulrike

    2013-04-01

    Due to the recent surge in environmental consciousness and the need to address childhood obesity, Farm to School programs have gained momentum. Even though Farm to School programs have increased in popularity, many schools still fail to take advantage of the benefits from such programs. School food service employees' lack of familiarity with the benefits of Farm to School programs or the means to overcome obstacles to implement such programs, along with school size, may represent key variables that serve to explain why more schools do not purchase more local foods for their schools. This study used a convenience sampling methodology to gather information regarding food service employees' perceptions of the benefits and obstacles and their attitudes to purchasing and serving local foods in their schools. A self-administered questionnaire was used to collect data from school food service employees in southern Illinois. Data (n=151) were collected from 60 schools, representing 16 counties during the month of December, 2009. Purchasers from large- and medium-size schools perceived the "ability to know product sources" as a greater benefit to purchasing local food and perceived "cost of food," "adequate volume," "reliable supply of food quantity," "payment arrangement," and "packing material" as greater obstacles (p<0.05) compared to small schools. In addition, results indicated that food service employees were interested in receiving training to prepare and serve more local foods. Findings from this study indicate a need for continued education, development, and training to better prepare school food service purchasers in southern Illinois for how to buy more local foods to meet the 2020 legislation requiring schools to purchase at least 10% locally.

  11. Bacterial Respiration and Growth Rates Affect the Feeding Preferences, Brood Size and Lifespan of Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Li Yu

    Full Text Available Bacteria serve as live food and nutrients for bacterial-feeding nematodes (BFNs in soils, and influence nematodes behavior and physiology through their metabolism. Five bacterial taxa (Bacillus amyloliquefaciens JX1, Variovorax sp. JX14, Bacillus megaterium JX15, Pseudomonas fluorescens Y1 and Escherichia coli OP50 and the typical BFN Caenorhabditis elegans were selected to study the effects of bacterial respiration and growth rates on the feeding preferences, brood size and lifespan of nematodes. P. fluorescens Y1 and E. coli OP50 were found to be more active, with high respiration and rapid growth, whereas B. amyloliquefaciens JX1 and B. megaterium JX15 were inactive. The nematode C. elegans preferred active P. fluorescens Y1 and E. coli OP50 obviously. Furthermore, worms that fed on these two active bacteria produced more offspring but had shorter lifespan, while inactive and less preferred bacteria had increased nematodes lifespan and decreased the brood size. Based on these results, we propose that the bacterial activity may influence the behavior and life traits of C. elegans in the following ways: (1 active bacteria reproduce rapidly and emit high levels of CO2 attracting C. elegans; (2 these active bacteria use more resources in the nematodes' gut to sustain their survival and reproduction, thereby reducing the worm's lifespan; (3 inactive bacteria may provide less food for worms than active bacteria, thus increasing nematodes lifespan but decreasing their fertility. Nematodes generally require a balance between their preferred foods and beneficial foods, only preferred food may not be beneficial for nematodes.

  12. Bacterial Respiration and Growth Rates Affect the Feeding Preferences, Brood Size and Lifespan of Caenorhabditis elegans.

    Science.gov (United States)

    Yu, Li; Yan, Xiaomei; Ye, Chenglong; Zhao, Haiyan; Chen, Xiaoyun; Hu, Feng; Li, Huixin

    2015-01-01

    Bacteria serve as live food and nutrients for bacterial-feeding nematodes (BFNs) in soils, and influence nematodes behavior and physiology through their metabolism. Five bacterial taxa (Bacillus amyloliquefaciens JX1, Variovorax sp. JX14, Bacillus megaterium JX15, Pseudomonas fluorescens Y1 and Escherichia coli OP50) and the typical BFN Caenorhabditis elegans were selected to study the effects of bacterial respiration and growth rates on the feeding preferences, brood size and lifespan of nematodes. P. fluorescens Y1 and E. coli OP50 were found to be more active, with high respiration and rapid growth, whereas B. amyloliquefaciens JX1 and B. megaterium JX15 were inactive. The nematode C. elegans preferred active P. fluorescens Y1 and E. coli OP50 obviously. Furthermore, worms that fed on these two active bacteria produced more offspring but had shorter lifespan, while inactive and less preferred bacteria had increased nematodes lifespan and decreased the brood size. Based on these results, we propose that the bacterial activity may influence the behavior and life traits of C. elegans in the following ways: (1) active bacteria reproduce rapidly and emit high levels of CO2 attracting C. elegans; (2) these active bacteria use more resources in the nematodes' gut to sustain their survival and reproduction, thereby reducing the worm's lifespan; (3) inactive bacteria may provide less food for worms than active bacteria, thus increasing nematodes lifespan but decreasing their fertility. Nematodes generally require a balance between their preferred foods and beneficial foods, only preferred food may not be beneficial for nematodes.

  13. Social acceptance of gifted pupils and pupils with additional professional help in elementary school

    Directory of Open Access Journals (Sweden)

    Marina Horvat

    2014-02-01

    Full Text Available Studies of peer relations in school settings are typically conducted on normative samples of pupils. Less is known about subgroups of pupils with some exceptionalities who may be more vulnerable to developing peer problems in school and are subsequently at risk for later maladjustment. The purpose of present study was therefore to examine social acceptance of gifted pupils and pupils with additional professional help in 6th and 8th-grade of regular elementary school. 194 pupils (50.5% girls from 12 classes participated in the study; 16 of them (8.3% were pupils with additional professional help (APH, 39 gifted pupils (20.1% and one gifted pupil with APH. A composite positive and negative nomination sociometric procedure was employed. Most of the pupils with APH were in rejected and average sociometric group. Pupils with APH received the lowest number of positive and reciprocal nominations and the highest number of negative nominations. Compared to gifted pupils they were less accepted, although no difference in acceptance was found compared to the non-APH pupils. Results showed no significant differences in acceptance of pupils with APH in regard to grade level or gender. Gifted children received the highest number of positive and reciprocal and the lowest number of negative nominations. They were more likely to be average and popular, although no differences in acceptance was found compared to non-gifted pupils. Results suggest the importance of investigating subgroups of pupils with APH in future research.

  14. Portion size variably affects food intake of 6-year-old and 4-year-old children in Kunming, China.

    Science.gov (United States)

    Smith, Lindsey; Conroy, Katharine; Wen, Hongmei; Rui, Li; Humphries, Debbie

    2013-10-01

    Age and portion size have been found to influence food intake in American children but have not been examined in an international context. This study evaluated the association between age and the effects of portion size on the food intake of kindergarteners in Kunming, China. Using a within-subjects crossover design in a classroom setting, 173 children in two age groups, mean age 4.2 years and 6.1 years, were served a predefined reference, small (-30%) and large (+30%) portion of rice, vegetables, and a protein source during lunchtime over three consecutive days. Each portion was weighed before and after the meal to determine amount of food consumed. Linear mixed modeling, controlling for repeated measures and clustering by classroom, was used to compare food intake under small and large portion size conditions to the reference portion. Children ate significantly less food when served small portions. When served a large portion, 6-year-old children increased food intake while 4-year-old children decreased food intake in comparison to the reference portion. Findings indicate that portion size affects food intake in Chinese children 4-6-years old. Older children show larger increases in food intake with increased portion size than do younger children.

  15. Fully Optimized Shaped Pupils for Arbitrary Apertures

    Science.gov (United States)

    Carlotti, Alexis; Vanderbei, R.; Kasdin, N. J.; Che, G.

    2012-01-01

    Optimal apodization masks for monolithic and segmented apertures are presented, with and without central obstruction and spider vanes. Examples of optimal masks are shown for several ground-based telescopes (The Subaru, Keck, Gemini, Palomar and Very Large telescopes). We also discuss the case of extremely large telescopes. Various high-contrast regions are considered with different inner and outer working angles, shapes and contrasts. These parameters are chosen to fit the specific constraints of each instrument, in particular those set by the dedicated coronagraphic adaptive optics system. Because of the limited size of the high-contrast regions, all the masks that result from these optimizations tend to have binary transmissions, and are thus as achromatic as previous shaped pupils. Effort is put on obtaining structurally connected masks. We intend to test these new shaped pupils in Princeton's high-contrast imaging laboratory, and to this end we explore different techniques to make the masks, such as cutting them in a metal layer, laying them on a glass substrate, or using a MOEMS device.

  16. Personality and Pupil Control Behavior.

    Science.gov (United States)

    Helsel, A. Ray

    Pupil control behavior is conceptualized as a continuum ranging from custodialism, which views students as irresponsible and undisciplined and needing strictness and punishment, to humanism, which emphasizes a democratic atmosphere in which students are capable of self-discipline and are treated accordingly. The theoretical framework for this…

  17. Adaptive instruction and pupil achievement

    NARCIS (Netherlands)

    Houtveen, A.A M; Booy, N; de Jong, Robert (Rob); van de Grift, W.J C M

    1999-01-01

    In this article the results are reported of a quasi-experiment on effects of adaptive instruction on reading results of children in the first year of reading instruction in Dutch primary schools. The research involved 456 pupils from 23 schools (12 experimental and 11 control group schools). Teacher

  18. The Texas Weighted Pupil Study.

    Science.gov (United States)

    Busselle, Tish Newman

    According to the weighted pupil philosophy, the essence of equal educational opportunity is not in providing equal amounts of funds for the education of each child, but in providing the varying amounts of funds needed to insure a financial basis for giving each child an equal opportunity to obtain an education which meets his needs. This paper…

  19. Three-zone pupil filters

    Science.gov (United States)

    Sheppard, Colin J. R.; Campos, Juan; Escalera, Juan C.; Ledesma, Silvia

    2008-07-01

    The performance of pupil filters consisting of three zones each of constant complex amplitude transmittance is investigated. For filters where the transmittance is real, different classes of potentially useful filter are identified. These include leaky filters with an inner zone of low amplitude transmittance, pure phase filters with phase change of π, and equal area filters.

  20. Middle School Pupils Write Haiku.

    Science.gov (United States)

    Ediger, Marlow

    Pupils in the middle school can be motivated to enjoy and write haiku poetry. A student teacher taught two lessons to a sixth grade class in haiku writing. First, the student teacher read three haikus aloud to students. After discovering the characteristics of a haiku from two models, the class as a whole wrote a haiku based on slides from their…

  1. Personality and Pupil Control Behavior.

    Science.gov (United States)

    Helsel, A. Ray

    Pupil control behavior is conceptualized as a continuum ranging from custodialism, which views students as irresponsible and undisciplined and needing strictness and punishment, to humanism, which emphasizes a democratic atmosphere in which students are capable of self-discipline and are treated accordingly. The theoretical framework for this…

  2. Fractal images induce fractal pupil dilations and constrictions.

    Science.gov (United States)

    Moon, P; Muday, J; Raynor, S; Schirillo, J; Boydston, C; Fairbanks, M S; Taylor, R P

    2014-09-01

    Fractals are self-similar structures or patterns that repeat at increasingly fine magnifications. Research has revealed fractal patterns in many natural and physiological processes. This article investigates pupillary size over time to determine if their oscillations demonstrate a fractal pattern. We predict that pupil size over time will fluctuate in a fractal manner and this may be due to either the fractal neuronal structure or fractal properties of the image viewed. We present evidence that low complexity fractal patterns underlie pupillary oscillations as subjects view spatial fractal patterns. We also present evidence implicating the autonomic nervous system's importance in these patterns. Using the variational method of the box-counting procedure we demonstrate that low complexity fractal patterns are found in changes within pupil size over time in millimeters (mm) and our data suggest that these pupillary oscillation patterns do not depend on the fractal properties of the image viewed.

  3. Pupils teach to pupils about genetics or global warming

    Science.gov (United States)

    Cuny, Delphine

    2013-04-01

    The idea of this project is to put pupils in a teaching situation. Classes of teenagers go to primary schools and animate a science workshop. Junior pupils are separated in small groups and they attend two different sessions in the same half-day. The whole workshop consists of 4 sessions. Each session is organized with an activity (microscope observation, counting of chromosomes, drawing of a curve, etc.) in which senior pupils coach the younger, and ends with a debate or an assessment. The first experiment of this type of project was realized with a class of 14 to 15 year old pupils on the theme: How do your parents transmit your characteristics? The four sessions are attended in disorder but when knowledge of other sessions are necessary, senior pupils explain them at the beginning of the session. Junior pupils have a notebook to write their activities and to note their conclusions. Session 1: What did my father give to make me? Drawing and measuring microscopic observations of human spermatozoons. Conclusion: my father gave a spermatozoon which measures less than one mm long, this spermatozoon met my mother's egg and it made my first cell. Session 2: What does the program that made me look like? Microscope observation of blood cells, identification of chromosomes in the core. On microscope pictures, counting of chromosomes. Conclusion: My program is in each cell of my body, inside the core. Sometimes, in this core, we can observe short sticks that are called chromosomes. All human beings have the same number of chromosomes in their cells: 46. Session 3: Where do my chromosomes come from? Counting of chromosomes in spermatozoons or ovums and playing with sets of chromosomes to deduct sex of a baby. Conclusion: Daddy gave me 23 chromosomes and mummy gave me 23 chromosomes too. My program is then constituted from half of daddy's program and half of mummy's program. My brothers and sisters also have half and half, but not the same halves! Session 4: Where is the

  4. Navy Bean Flour Particle Size and Protein Content Affect Cake Baking and Batter Quality(1).

    Science.gov (United States)

    Singh, Mukti; Byars, Jeffrey A; Liu, Sean X

    2015-06-01

    Whole navy bean flour and its fine and coarse particle size fractions were used to completely replace wheat flour in cakes. Replacement of wheat flour with whole bean flour significantly increased the protein content. The protein content was adjusted to 3 levels with navy bean starch. The effect of navy bean flour and its fractions at 3 levels of protein on cake batter rheology and cake quality was studied and compared with wheat flour samples. Batters prepared from navy bean flour and its fractions had higher viscosity than the cake flour. Reducing the protein content by addition of starch significantly lowered the viscosity of cake batters. The whole navy bean flour and coarse bean fraction cakes were softer than cakes made with wheat flour but had reduced springiness. Principal component analysis showed a clear discrimination of cakes according to protein. It also showed that low protein navy bean flour cakes were similar to wheat flour cakes. Navy bean flour with protein content adjusted to the level of cake (wheat) flour has potential as a healthy alternative in gluten-free cakes. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  5. Granular size of potato starch affects structural properties, octenylsuccinic anhydride modification and flowability.

    Science.gov (United States)

    Wang, Chan; Tang, Chuan-He; Fu, Xiong; Huang, Qiang; Zhang, Bin

    2016-12-01

    Native potato starch (PS) granules were separated into three size fractions: larger than 30μm (P-L), 15-30μm (P-M), and smaller than 15μm (P-S). The morphological and crystalline structure of fractionated potato starches were investigated by light and scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The P-L fraction showed ellipsoidal shape and B-type X-ray pattern, whereas the P-S fraction had spherical shape and A-type pattern. The fluorophore-assisted capillary electrophoresis data showed that the P-L fraction had more B2 chains and less short A and B1 chains than the P-S counterparts. Smaller granules with larger specific surface area had higher degree of substitution when reacted with octenylsuccinic anhydride (OSA), and showed more uniform distribution of octenylsuccinate substituents. Both OSA modified and unmodified P-S samples showed higher flowability compared with the P-L counterparts.

  6. Urban bat communities are affected by wetland size, quality, and pollution levels.

    Science.gov (United States)

    Straka, Tanja Maria; Lentini, Pia Eloise; Lumsden, Linda Faye; Wintle, Brendan Anthony; van der Ree, Rodney

    2016-07-01

    Wetlands support unique biota and provide important ecosystem services. These services are highly threatened due to the rate of loss and relative rarity of wetlands in most landscapes, an issue that is exacerbated in highly modified urban environments. Despite this, critical ecological knowledge is currently lacking for many wetland-dependent taxa, such as insectivorous bats, which can persist in urban areas if their habitats are managed appropriately. Here, we use a novel paired landscape approach to investigate the role of wetlands in urban bat conservation and examine local and landscape factors driving bat species richness and activity. We acoustically monitored bat activity at 58 urban wetlands and 35 nonwetland sites (ecologically similar sites without free-standing water) in the greater Melbourne area, southeastern Australia. We analyzed bat species richness and activity patterns using generalized linear mixed-effects models. We found that the presence of water in urban Melbourne was an important driver of bat species richness and activity at a landscape scale. Increasing distance to bushland and increasing levels of heavy metal pollution within the waterbody also negatively influenced bat richness and individual species activity. Areas with high levels of artificial night light had reduced bat species richness, and reduced activity for all species except those adapted to urban areas, such as the White-striped free-tailed bat (Austronomus australis). Increased surrounding tree cover and wetland size had a positive effect on bat species richness. Our findings indicate that wetlands form critical habitats for insectivorous bats in urban environments. Large, unlit, and unpolluted wetlands flanked by high tree cover in close proximity to bushland contribute most to the richness of the bat community. Our findings clarify the role of wetlands for insectivorous bats in urban areas and will also allow for the preservation, construction, and management of wetlands

  7. Maternal immune activation affects litter success, size and neuroendocrine responses related to behavior in adult offspring.

    Science.gov (United States)

    French, Susannah S; Chester, Emily M; Demas, Gregory E

    2013-07-02

    It is increasingly evident that influences other than genetics can contribute to offspring phenotype. In particular, maternal influences are an important contributing factor to offspring survival, development, physiology and behavior. Common environmental pathogens such as viral or bacterial microorganisms can induce maternal immune responses, which have the potential to alter the prenatal environment via multiple independent pathways. The effects of maternal immune activation on endocrine responses and behavior are less well studied and provide the basis for the current study. Our approach in the current study was two-pronged: 1) quantify sickness responses during pregnancy in adult female hamsters experiencing varying severity of immune responsiveness (i.e., differing doses of lipopolysaccharide [LPS]), and 2) assess the effects of maternal immune activation on offspring development, immunocompetence, hormone profiles, and social behavior during adulthood. Pregnancy success decreased with increasing doses of LPS, and litter size was reduced in LPS dams that managed to successfully reproduce. Unexpectedly, pregnant females treated with LPS showed a hypothermic response in addition to the more typical anorexic and body mass changes associated with sickness. Significant endocrine changes related to behavior were observed in the offspring of LPS-treated dams; these effects were apparent in adulthood. Specifically, offspring from LPS treated dams showed significantly greater cortisol responses to stressful resident-intruder encounters compared with offspring from control dams. Post-behavior cortisol was elevated in male LPS offspring relative to the offspring of control dams, and was positively correlated with the frequency of bites during agonistic interactions, and cortisol levels in both sexes were related to defensive behaviors, suggesting that changes in hypothalamo-pituitary-adrenal axis responsiveness may play a regulatory role in the observed behavioral

  8. Fire affects size and shape of Fabiana imbricata Shurblands in northwestern Patagonia

    Science.gov (United States)

    Oddi, Facundo; Ghermandi, Luciana

    2010-05-01

    Fire is a major environmental ecological agent acting in the landscape configuration and a factor that models vegetation in Mediterranean environments. Fire impacts differently in the landscape due to the intrinsic heterogeneity of the environments and the characteristics associated with each fire event. After fire, density of patches may be increased and the size of them may be reduced because fire generates areas of different successional stages. Landscape ecology seems to be the ideal theoretical approach to study the fire impact in fire prone environments. Landscape ecology has been greatly favoured by a significant progress in the last years of geographic information technologies (GIT) (remote sensing, GIS, GPS). The study area of this work is the San Ramon ranch (22,000 ha) located in Northwester Patagonia in the ecotone between the sub Antarctic forest in the West and the Patagonian steppe in the East. We studied sectors of the ranch with different fire recurrence in the last 40 years and we mapped Fabiana imbricata shrubland with GPS. This specie is a native shrub characteristic of Northwester Patagonia grasslands and its dynamic is not very known. Shrublands compete for the space with palatable grasses that are used for forage and livestock production, the main economic resource of the region. We analysed the mapped patches with GIS software, and we assessed landscape metrics to determine differences between sites with different fire recurrence. In the future we foresee the integrated use of satellite imagery with different resolution to add to GIS other important spatial variables (topography, hydrography, aspect, soil) to develop models that can explain landscape metrics, spatial configuration and the potential shrub invasion in the grassland.

  9. 苏州市小学生焦虑情绪及其影响因素调查%Survey on Pupils' Anxiety and Its Affecting Factors in Suzhou City

    Institute of Scientific and Technical Information of China (English)

    袁媛; 祁宁

    2013-01-01

    Children's anxiety symptom has been a general concern of psychologists, educators and other social workers. In order to investigate the rate and risk factors of children's anxiety symp-toms, Revised Children's Manifest Anxiety Scale was used to sur-vey children's anxiety symptoms in Suzhou. The result revealed that the rate of anxiety symptoms was high in pupils. And the risk factors of anxiety symptoms included gender, achievements, do-mestic violence, playing computer games and study pressure. This research indicated anxiety symptom is an obvious problem in pupils , and educators must pay much attention to this point.%  青少年焦虑症状已逐渐成为心理、教育及其他社会工作者普遍关心的重要问题之一。为探讨儿童的焦虑症状发生率及其影响因素,本研究采用儿童焦虑量表修订版对苏州地区小学生进行了焦虑情绪和影响因素调查。研究结果表明目前小学生的焦虑情绪发生率较高,焦虑情绪的影响因素有:性别、成绩、家庭暴力、玩电脑和网络游戏、学习压力。此研究表明焦虑情绪是困扰小学生的一个较明显的心理问题,值得广大心理和教育工作者重视。

  10. Factors affecting size and swelling of poly(ethylene glycol) microspheres formed in aqueous sodium sulfate solutions without surfactants.

    Science.gov (United States)

    Nichols, Michael D; Scott, Evan A; Elbert, Donald L

    2009-10-01

    The LCST behavior of poly(ethylene glycol) (PEG) in aqueous sodium sulfate solutions was exploited to fabricate microspheres without the use of other monomers, polymers, surfactants or organic solvents. Reactive PEG derivatives underwent thermally induced phase separation to produce spherical PEG-rich domains that coarsened in size pending gelation, resulting in stable hydrogel microspheres between approximately 1 and 100 microns in size. The time required to reach the gel point during the coarsening process and the extent of crosslinking after gelation both affected the final microsphere size and swelling ratio. The gel point could be varied by pre-reaction of the PEG derivatives below the cloud point, or by controlling pH and temperature above the cloud point. Pre-reaction brought the PEG derivatives closer to the gel point prior to phase separation, while the pH and temperature influenced the rate of reaction. Dynamic light scattering indicated a percolation-to-cluster transition about 3-5 min following phase separation. The mean radius of PEG-rich droplets subsequently increased with time to the 1/4th power until gelation. PEG microspheres produced by these methods with controlled sizes and densities may be useful for the production of modular scaffolds for tissue engineering.

  11. Diet calcium level but not calcium supplement particle size affects bone density and mechanical properties in ovariectomized rats.

    Science.gov (United States)

    Shahnazari, Mohammad; Martin, Berdine R; Legette, Leecole L; Lachcik, Pamela J; Welch, Jo; Weaver, Connie M

    2009-07-01

    Calcium (Ca) supplements, especially Ca carbonate (CaCO3), are the main alternative sources of dietary Ca and an important part of a treatment regimen for osteoporosis, the most common metabolic bone disorder of aging and menopause. In a female ovariectomized (OVX) rat model for studying postmenopausal osteoporosis, we tested the hypothesis that a small compared with a large particle size of CaCO3 (13.0- vs. 18.5-mum geometric diameter) would result in increased Ca balance and subsequently bone mass and that this would be affected by dietary Ca level. We used 6-mo-old rats that were OVX either at 6 or 3 mo of age as models of early or stable menopausal status, respectively. The rats received semipurified diets that contained either 0.4 or 0.2% dietary Ca provided from CaCO3 of 2 particle sizes. A group of Sham-operated rats with intact ovaries served as control and were fed 0.4% dietary Ca from large particles. Estrogen deficiency as a result of ovariectomy had an adverse effect on bone density, mineral content, and bone mechanical properties (P < 0.001). Reducing dietary Ca from 0.4 to 0.2% resulted in significant adverse effects on bone density and mechanical properties (P < 0.001). The particle size of CaCO3 did not affect total Ca balance, bone dual energy X-ray absorptiometry and peripheral quantitative computed tomography indices, bone ash and Ca content, or the mechanical determinants of bone strength. We conclude that a decrease in particle size of CaCO3 to 70% of that typically found in Ca supplements does not provide a benefit to overall Ca metabolism or bone characteristics and that the amount of Ca consumed is of greater influence in enhancing Ca nutrition and skeletal strength.

  12. 78 FR 45969 - Trade Barriers That U.S. Small and Medium-Sized Enterprises Perceive as Affecting Exports to the...

    Science.gov (United States)

    2013-07-30

    ... COMMISSION Trade Barriers That U.S. Small and Medium-Sized Enterprises Perceive as Affecting Exports to the... and Medium- sized Enterprises Perceive as Affecting Exports to the European Union. DATES: September 13... ). Persons with mobility impairments who will need special assistance in gaining access to the...

  13. 78 FR 51746 - Trade Barriers That U.S. Small and Medium-sized Enterprises Perceive as Affecting Exports to the...

    Science.gov (United States)

    2013-08-21

    ... COMMISSION Trade Barriers That U.S. Small and Medium-sized Enterprises Perceive as Affecting Exports to the... Barriers that U.S. Small and Medium-sized Enterprises Perceive as Affecting Exports to the European Union... ). Persons with mobility impairments who will need special assistance in gaining access to the...

  14. Effects of Different Teaching Styles on the Teacher Behaviours that Influence Motivational Climate and Pupils' Motivation in Physical Education

    Science.gov (United States)

    Morgan, Kevin; Kingston, Kieran; Sproule, John

    2005-01-01

    This study investigated the effects of different teaching styles on the teaching behaviours that influence motivational climate and pupils' cognitive and affective responses in physical education. Four (two male, two female) initial teacher education (ITE) students and 92 pupils (47 boys, 45 girls), from two schools in the UK, participated in the…

  15. Circadian and wake-dependent effects on the pupil light reflex in response to narrow-bandwidth light pulses.

    Science.gov (United States)

    Münch, Mirjam; Léon, Lorette; Crippa, Sylvain V; Kawasaki, Aki

    2012-07-03

    Nonvisual light-dependent functions in humans are conveyed mainly by intrinsically photosensitive retinal ganglion cells, which express melanopsin as photopigment. We aimed to identify the effects of circadian phase and sleepiness across 24 hours on various aspects of the pupil response to light stimulation. We tested 10 healthy adults hourly in two 12-hour sessions covering a 24-hour period. Pupil responses to narrow bandwidth red (635 ± 18 nm) and blue (463 ± 24 nm) light (duration of 1 and 30 seconds) at equal photon fluxes were recorded, and correlated with salivary melatonin concentrations at the same circadian phases and to subjective sleepiness ratings. The magnitude of pupil constriction was determined from minimal pupil size. The post-stimulus pupil response was assessed from the pupil size at 6 seconds following light offset, the area within the redilation curve, and the exponential rate of redilation. Among the measured parameters, the pupil size 6 seconds after light offset correlated with melatonin concentrations (P light stimulation correlated with subjective sleepiness (P light as a marker of intrinsic melanopsin activity demonstrated a circadian modulation. In contrast, the effect of sleepiness was more apparent in the cone contribution to the pupil response. Thus, pupillary responsiveness to light is under influence of the endogenous circadian clock and subjective sleepiness.

  16. On written expression of primary school pupils

    Directory of Open Access Journals (Sweden)

    Stevanović Jelena

    2009-01-01

    Full Text Available Normative rules of standard Serbian language are acquired during primary and secondary education through curriculum demands of Serbian language instruction, which takes place in three fields: grammar, orthography and culture of expression. Topic of interest in this paper is the quality of written expression of 6th and 7th grade pupils, in the context of all three fields specified to be mastered by the curriculum of Serbian language. Research comprised 148 primary school pupils from Belgrade. Linguistic analysis of spontaneously created written text was performed, in the conditions where it was not explicitly demanded form the pupil to write correctly. The results indicate that the majority of pupils make spelling and grammatical errors, meeting the condition for the basic level of mastering the knowledge in Serbian language according to the standards specified for the end of compulsory education. In addition to this, a considerable majority of pupils has a satisfactory level of culture of written expression. Pupils more often make spelling than grammatical errors. Seventh grade pupils are better than sixth grade pupils with respect to adhering to grammar rules and according to culture of written expression, while the mark in Serbian language and general school achievement of pupils correlate only with the degree of adhering to the orthographic rules. It was concluded that not only individual programs of support for pupils who make more errors are necessary, but also launching national projects for the development of linguistic competence of the young in Serbia.

  17. Factors Associated With Pupil Toilet Use in Kenyan Primary Schools

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    Joshua V. Garn

    2014-09-01

    Full Text Available The purpose of this study was to quantify how school sanitation conditions are associated with pupils’ use of sanitation facilities. We conducted a longitudinal assessment in 60 primary schools in Nyanza Province, Kenya, using structured observations to measure facility conditions and pupils’ use at specific facilities. We used multivariable mixed regression models to characterize how pupil to toilet ratio was associated with toilet use at the school-level and also how facility conditions were associated with pupils’ use at specific facilities. We found a piecewise linear relationship between decreasing pupil to toilet ratio and increasing pupil toilet use (p < 0.01. Our data also revealed significant associations between toilet use and newer facility age (p < 0.01, facility type (p < 0.01, and the number of toilets in a facility (p < 0.01. We found some evidence suggesting facility dirtiness may deter girls from use (p = 0.06, but not boys (p = 0.98. Our study is the first to rigorously quantify many of these relationships, and provides insight into the complexity of factors affecting pupil toilet use patterns, potentially leading to a better allocation of resources for school sanitation, and to improved health and educational outcomes for children.

  18. How group size affects vigilance dynamics and time allocation patterns: the key role of imitation and tempo.

    Directory of Open Access Journals (Sweden)

    Pablo Michelena

    Full Text Available In the context of social foraging, predator detection has been the subject of numerous studies, which acknowledge the adaptive response of the individual to the trade-off between feeding and vigilance. Typically, animals gain energy by increasing their feeding time and decreasing their vigilance effort with increasing group size, without increasing their risk of predation ('group size effect'. Research on the biological utility of vigilance has prevailed over considerations of the mechanistic rules that link individual decisions to group behavior. With sheep as a model species, we identified how the behaviors of conspecifics affect the individual decisions to switch activity. We highlight a simple mechanism whereby the group size effect on collective vigilance dynamics is shaped by two key features: the magnitude of social amplification and intrinsic differences between foraging and scanning bout durations. Our results highlight a positive correlation between the duration of scanning and foraging bouts at the level of the group. This finding reveals the existence of groups with high and low rates of transition between activities, suggesting individual variations in the transition rate, or 'tempo'. We present a mathematical model based on behavioral rules derived from experiments. Our theoretical predictions show that the system is robust in respect to variations in the propensity to imitate scanning and foraging, yet flexible in respect to differences in the duration of activity bouts. The model shows how individual decisions contribute to collective behavior patterns and how the group, in turn, facilitates individual-level adaptive responses.

  19. Planting densities and bird and rodent absence affect size distributions of four dicots in synthetic tallgrass communities.

    Science.gov (United States)

    Martínez-Garza, Cristina; Saha, Sonali; Torres, Veronica; Brown, Joel S; Howe, Henry F

    2004-05-01

    Variability in the size distributions of populations is usually studied in monocultures or in mixed plantings of two species. Variability of size distributions of populations in more complex communities has been neglected. The effects of seeding density (35 or 350 seeds/species/m2) and presence of small vertebrates on the variability of size distributions were studied for a total of 1,920 individuals of 4 species in replicated synthetic communities of 18 species in northern Illinois. End-of season height and above-ground biomass were measured for prairie perennials Dalea purpurea (purple prairie clover), Echinacea purpurea (purple coneflower), Desmanthus illinoensis (Illinois bundleflower) and Heliopsis helianthoides (early sunflower). Variability in biomass distribution of the four target species was twice as great at low than at high densities when small vertebrates were excluded. Our results suggest that inter- and intraspecific competition may affect all individuals more under high-density conditions, thereby reducing the variability in their biomass distributions within this community. This result, a consequence of plant-plant interaction, is obscured when small birds or mammals are present, presumably because either or both add variance that overwhelms the pattern.

  20. The Langerhans islet cells of female rabbits are differentially affected by hypothyroidism depending on the islet size.

    Science.gov (United States)

    Rodríguez-Castelán, J; Nicolás, L; Morimoto, S; Cuevas, E

    2015-04-01

    Effects of hypothyroidism on the glucose and insulin levels are controversial, and its impact on the Langerhans islet morphology of adult subjects has been poorly addressed. In spite of hypothyroidism and diabetes mellitus are more frequent in females than in males, most studies using animal models have been done in males. The effect of hypothyroidism on the immunolabeling of thyroid hormone receptors (TRs) and thyrotropin receptor (TSHR) of islet cells is unknown. The aim of this study was to determine the effect of hypothyroidism on the glucose and insulin concentrations, morphometry of islets, and immunostaining of TRs α1-2 and β1 and TSHR of islet cells in female rabbits. Control and hypothyroid (0.02% of methimazole for 30 days) animals were used to quantify blood levels of glucose and insulin, density of islets, cross-sectional area (CSA) of islets, number of cells per islet, cell proliferation, and the immunolabeling of TRs α1-2, TRβ1, and TSHR. Student's t or Mann-Whitney-U tests, two-way ANOVAs, and Fischer's tests were applied. Concentrations of glucose and insulin, as well as the insulin resistance were similar between groups. Hypothyroidism did not affect the density or the CSA of islets. The analysis of islets by size showed that hypothyroidism reduced the cell number in large and medium islets, but not in small ones. In small islets, cell proliferation was increased. The immunoreactivity of TRα1-2, TRβ1, and TSHR was increased by hypothyroidism in all islet sizes. Our results show that hypothyroidism affects differentially the islet cells depending on the size of islets.

  1. The relationship between pupil diameter and pain by the administration of morphine and antidepressant drugs in mice.

    Science.gov (United States)

    Onal, A; Tuğlular, I

    1999-07-01

    Because the pain sensation is subjective, it is difficult to evaluate the responses to analgesic drugs. Some analgesics that affect the central nervous system are known to change the pupil diameter. The pupil diameter is a more objective criterion that shows the drug effect. We studied the relation between the pupil diameter and analgesia responses to morphine and antidepressants by using the selective micro-receptor agonist morphine (2 and 4 mg/kg), the noradrenaline reuptake inhibitor desipramine (7.5 and 10 mg/kg), the mixed serotonergic and noradrenergic uptake inhibitor and cholinergic receptor antagonist amitriptyline (2.5 and 5 mg/kg), and the selective serotonin reuptake inhibitor sertraline (2.5 and 5 mg/kg) in mice. Both monocular microscopy to assess pupil measurement and the hot-plate test to assess nociceptive thresholds were used in the same animals. We found that morphine played an important role in both mydriasis and analgesia, whereas amitriptyline and desipramine had a greater effect on pupil response than on nociception. Sertraline produced antinociception without causing a change in pupil diameter. As a result, although the pupil response is an important criterion in evaluating the analgesic effect of morphine, it is not possible to put forward the same criterion for the antidepressant drugs. Because different neurotransmitters are involved in pupil and pain mechanisms of antidepressant drugs, it is difficult to evaluate the analgesic response with the pupil diameter.

  2. Pupils as Active Participants: Diamond Ranking as a Tool to Investigate Pupils' Experiences of Classroom Practices

    Science.gov (United States)

    Niemi, Reetta; Kumpulainen, Kristiina; Lipponen, Lasse

    2015-01-01

    This article is based on a pedagogical action research initiative carried out in a Finnish primary school. Twenty-four 5th grade pupils and their teacher participated in the study. The research initiative was guided by two questions: (1) How do pupils experience their classroom practices? (2) How can pupils participate in the process of developing…

  3. Linking Electrical Stimulation of Human Primary Visual Cortex, Size of Affected Cortical Area, Neuronal Responses, and Subjective Experience.

    Science.gov (United States)

    Winawer, Jonathan; Parvizi, Josef

    2016-12-21

    Electrical brain stimulation (EBS) complements neural measurements by probing the causal relationship between brain and perception, cognition, and action. Many fundamental questions about EBS remain unanswered, including the spatial extent of cortex responsive to stimulation, and the relationship between the circuitry engaged by EBS and the types of neural responses elicited by sensory stimulation. Here, we measured neural responses and the effects of EBS in primary visual cortex in four patients implanted with intracranial electrodes. Using stimulation, behavior, and retinotopic mapping, we show the relationship between the size of affected cortical area and the magnitude of electrical charge. Furthermore, we show that the spatial location of electrically induced visual sensations is matched to the receptive field of the cortical site measured with broadband field potentials, and less so with event related potentials. Together, these findings broaden our knowledge about the mechanism of EBS and the neuromodulation of the human brain. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Glyoxalase 1 overexpression does not affect atherosclerotic lesion size and severity in ApoE-/- mice with or without diabetes

    DEFF Research Database (Denmark)

    Hanssen, Nordin M J; Brouwers, Olaf; Gijbels, Marion J

    2014-01-01

    AIMS: Advanced glycation end-products (AGEs) and their precursors have been associated with the development of atherosclerosis. We recently discovered that glyoxalase 1 (GLO1), the major detoxifying enzyme for AGE precursors, is decreased in ruptured human plaques, and that levels of AGEs......E(-/-) huGLO1(+/-) (n = 20) mice. To induce diabetes, we injected a subset with streptozotocin (STZ) to generate diabetic ApoE(-/-) (n = 8) and ApoE(-/-) huGLO1(+/-) (n = 13) mice. All mice were fed chow and sacrificed at 25 weeks of age. The GLO1 activity was three-fold increased in huGLO1(+/-) aorta......(+/-) overexpression. Although diabetic mice showed decreased GLO1 expression (P diabetic mice, GLO1 overexpression also did not affect the aortic root lesion size or inflammation in diabetic mice. CONCLUSION: In ApoE(-/-) mice with or without...

  5. The tale of the shrinking weapon: seasonal changes in nutrition affect weapon size and sexual dimorphism, but not contemporary evolution.

    Science.gov (United States)

    Miller, C W; McDonald, G C; Moore, A J

    2016-11-01

    Sexually selected traits are often highly variable in size within populations due to their close link with the physical condition of individuals. Nutrition has a large impact on physical condition, and thus, any seasonal changes in nutritional quality are predicted to alter the average size of sexually selected traits as well as the degree of sexual dimorphism in populations. However, although traits affected by mate choice are well studied, we have a surprising lack of knowledge of how natural variation in nutrition affects the expression of sexually selected weapons and sexual dimorphism. Further, few studies explicitly test for differences in the heritability and mean-scaled evolvability of sexually selected traits across conditions. We studied Narnia femorata (Hemiptera: Coreidae), an insect where males use their hind legs as weapons and the femurs are enlarged, to understand the extent to which weapon expression, sexual dimorphism and evolvability change across the actual range of nutrition available in the wild. We found that insects raised on a poor diet (cactus without fruit) are nearly monomorphic, whereas those raised on a high-quality diet (cactus with ripe fruit) are distinctly sexually dimorphic via the expression of large hind leg weapons in males. Contrary to our expectations, we found little evidence of a potential for evolutionary change for any trait measured. Thus, although we show weapons are highly condition dependent, and changes in weapon expression and dimorphism could alter evolutionary dynamics, our populations are unlikely to experience further evolutionary changes under current conditions. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  6. Pupil Control Ideology in Predicting Teacher Discipline Referrals.

    Science.gov (United States)

    Foley, Walter J.; Brooks, Robert

    1978-01-01

    Concludes that humanism in teachers is related to reporting fewer unresolvable conflicts with pupils and that pupil control ideology and subsequent teacher control behavior (the referring of pupils to the administration for disciplinary action) are related. (Author/IRT)

  7. Organizational Pressure, Personal Ideology and Teacher Pupil Control Behaviour.

    Science.gov (United States)

    Blust, Ross S.; Willower, Donald J.

    1979-01-01

    It was found that teachers' own views on pupil control predicted their pupil control behavior, while organizational pressures, represented by teacher perceptions of the pupil control views of colleagues and the principal, failed to do so. (Author/IRT)

  8. Toward Definition and Measurement of Pupil Control Behaviour

    Science.gov (United States)

    Helsel, A. Ray; Willower, Donald J.

    1974-01-01

    Pupil control is regarded as an integrative theme to explain the collection of extensive observations made in schools. This report attempts to define and measure pupil control behavior, a companion concept to pupil control ideology. (Author/WM)

  9. When size matters: differences in demineralized bone matrix particles affect collagen structure, mesenchymal stem cell behavior, and osteogenic potential.

    Science.gov (United States)

    Dozza, B; Lesci, I G; Duchi, S; Della Bella, E; Martini, L; Salamanna, F; Falconi, M; Cinotti, S; Fini, M; Lucarelli, E; Donati, D

    2017-04-01

    Demineralized bone matrix (DBM) is a natural, collagen-based, osteoinductive biomaterial. Nevertheless, there are conflicting reports on the efficacy of this product. The purpose of this study was to evaluate whether DBM collagen structure is affected by particle size and can influence DBM cytocompatibility and osteoinductivity. Sheep cortical bone was ground and particles were divided in three fractions with different sizes, defined as large (L, 1-2 mm), medium (M, 0.5-1 mm), and small (S, structure, with DBM-M being altered but not as much as DBM-S. DBM-M displayed a preferable trend in almost all biological characteristics tested, although all DBM particles revealed an optimal cytocompatibility. Subcutaneous implantation of DBM particles into immunocompromised mice resulted in bone induction only for DBM-M. When sheep MSC were seeded onto particles before implantation, all DBM particles were able to induce new bone formation with the best incidence for DBM-M and DBM-S. In conclusion, the collagen alteration in DBM-M is likely the best condition to promote bone induction in vivo. Furthermore, the choice of 0.5-1 mm particles may enable to obtain more efficient and consistent results among different research groups in bone tissue-engineering applications. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1019-1033, 2017.

  10. Aortopulmonary collateral flow is related to pulmonary artery size and affects ventricular dimensions in patients after the fontan procedure.

    Directory of Open Access Journals (Sweden)

    Heiner Latus

    Full Text Available BACKGROUND: Aortopulmonary collaterals (APCs are frequently found in patients with a single-ventricle (SV circulation. However, knowledge about the clinical significance of the systemic-to-pulmonary shunt flow in patients after the modified Fontan procedure and its potential causes is limited. Accordingly, the aim of our study was to detect and quantify APC flow using cardiovascular magnetic resonance (CMR and assess its impact on SV volume and function as well as to evaluate the role of the size of the pulmonary arteries in regard to the development of APCs. METHODS: 60 patients (mean age 13.3 ± 6.8 years after the Fontan procedure without patent tunnel fenestration underwent CMR as part of their routine clinical assessment that included ventricular functional analysis and flow measurements in the inferior vena cava (IVC, superior vena cava (SVC and ascending aorta (Ao. APC flow was quantified using the systemic flow estimator: (Ao - (IVC + SVC. Pulmonary artery index (Nakata index was calculated as RPA + LPA area/body surface area using contrast enhanced MR angiography. The patient cohort was divided into two groups according to the median APC flow: group 1 0.495 l/min/m(2. RESULTS: Group 1 patients had significant smaller SV enddiastolic (71 ± 16 vs 87 ± 25 ml/m(2; p=0.004 and endsystolic volumes (29 ± 11 vs 40 ± 21 ml/m(2; p=0.02 whereas ejection fraction (59 ± 9 vs 56 ± 13%; p=0.38 differed not significantly. Interestingly, pulmonary artery size showed a significant inverse correlation with APC flow (r=-0.50, p=0.002. CONCLUSIONS: Volume load due to APC flow in Fontan patients affected SV dimensions, but did not result in an impairment of SV function. APC flow was related to small pulmonary artery size, suggesting that small pulmonary arteries represent a potential stimulus for the development of APCs.

  11. Glyoxalase 1 overexpression does not affect atherosclerotic lesion size and severity in ApoE-/- mice with or without diabetes.

    Science.gov (United States)

    Hanssen, Nordin M J; Brouwers, Olaf; Gijbels, Marion J; Wouters, Kristiaan; Wijnands, Erwin; Cleutjens, Jack P M; De Mey, Jo G; Miyata, Toshio; Biessen, Erik A; Stehouwer, Coen D A; Schalkwijk, Casper G

    2014-10-01

    Advanced glycation end-products (AGEs) and their precursors have been associated with the development of atherosclerosis. We recently discovered that glyoxalase 1 (GLO1), the major detoxifying enzyme for AGE precursors, is decreased in ruptured human plaques, and that levels of AGEs are higher in rupture-prone plaques. We here investigated whether overexpression of human GLO1 in ApoE(-/-) mice could reduce the development of atherosclerosis. We crossed C57BL/6 ApoE(-/-) mice with C57BL/6 GLO1 overexpressing mice (huGLO1(+/-)) to generate ApoE(-/-) (n = 16) and ApoE(-/-) huGLO1(+/-) (n = 20) mice. To induce diabetes, we injected a subset with streptozotocin (STZ) to generate diabetic ApoE(-/-) (n = 8) and ApoE(-/-) huGLO1(+/-) (n = 13) mice. All mice were fed chow and sacrificed at 25 weeks of age. The GLO1 activity was three-fold increased in huGLO1(+/-) aorta, but aortic root lesion size and phenotype did not differ between mice with and without huGLO1(+/-) overexpression. We detected no differences in gene expression in aortic arches, in AGE levels and cytokines, in circulating cells, and endothelial function between ApoE(-/-) mice with and without huGLO1(+/-) overexpression. Although diabetic mice showed decreased GLO1 expression (P diabetic mice, GLO1 overexpression also did not affect the aortic root lesion size or inflammation in diabetic mice. In ApoE(-/-) mice with or without diabetes, GLO1 overexpression did not lead to decreased atherosclerotic lesion size or systemic inflammation. Increasing GLO1 levels does not seem to be an effective strategy to reduce glycation in atherosclerotic lesions, likely due to increased AGE formation through GLO1-independent mechanisms. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  12. THE ESTROGENIC AND ANTIANDROGENIC PESTICIDE METHOXYCHLOR ALTERS THE REPRODUCTIVE TRACT AND BEHAVIOR WITHOUT AFFECTING PITUITARY SIZE OR LH AND PROLACTIN SECRETION IN MALE RATS

    Science.gov (United States)

    The estrogenic and antiandrogenic pesticide methoxychlor alters the reproductive tract and behavior without affecting pituitary size or LH and prolactin secretion in male rats.Gray LE Jr, Ostby J, Cooper RL, Kelce WR.Endocrinology Branch, United States Environment...

  13. Heterosis in the second and third generation affects litter size in a crossbreed mink (Neovison vison) population

    DEFF Research Database (Denmark)

    Thirstrup, Janne Pia; Pertoldi, Cino; Larsen, Peter Foged

    2014-01-01

    and F3) after crossing. Thereafter, in the following generations, litter size dropped to a level comparable to the mean litter size of the midparent. Increased litter size in F2 compared to F1 indicated that maternal effects influenced litter size more than non-maternal effects. The heterosis was mainly...... caused by an increase in litter size compared to the Black parental line. This indicates that the Black line was affected by inbreeding depression prior to crossing. We also found that two-year old F1 females had significantly more offspring compared to one-year old F1 females...

  14. Pathophysiology of dilatation of pupils due to scorpion and snake envenomation and its therapeutic value: Clinical observations

    Science.gov (United States)

    Bawaskar, Himmatrao S; Bawaskar, Parag H; Bawaskar, Pramodini H

    2017-01-01

    Dilated nonreacting pupils are routinely taken as a sign of irreversible brain damage. Alpha-receptor stimulation (scorpion sting) and presynaptic acetylcholine receptor blocker (krait bite) may result in dilation of pupils without involvement of the brain. This study was aimed to clinically evaluate the response of pupils in scorpion sting and krait bite. Victims of scorpion sting and krait bite were chosen from Raigad district. Scorpion sting and krait bite cases were admitted to hospital and were clinically evaluated in detail regarding neurological manifestations. Both cases had nonreacting dilation of pupils, complete neurological recovery accompanied with reverse of pupillary size and its response to light. In scorpion sting and krait bite poisoning, dilated nonreacting pupils are not the signs of irreversible brain damage. PMID:28300747

  15. Pattern of ocular trauma among primary school pupils in Ilorin, Nigeria.

    Science.gov (United States)

    Ayanniyi, A A; Mahmoud, O A; Olatunji, F O; Ayanniyi, R O

    2009-06-01

    To report the pattern of ocular trauma among school pupils in Ilorin, Nigeria, a cross sectional survey of primary school children in 10 randomly selected primary schools within Ilorin, Nigeria was carried out between July 2005 and January 2006. Relevant ocular history and basic ocular examinations were carried out on the children that were selected from a multi-stage sampling process. Diagnosis of ocular trauma was based on historical recollection together with corroborating ocular signs among affected pupils. Ocular trauma was found among 11 (8 boys and 3 girls) out of 1393 (0.8%) pupils and their ages ranged from 5 to 13 years. The trauma related ocular pathology found among the 11 pupils included unilateral phthisis bulbi (2, 0.14%), couching (1, 0.07%) and retinal detachment (1, 0.07%) all leading to blindness in the affected eyes. There was also a unilateral visual impairment caused by traumatic optic atrophy. Others included eyelid bruises (2, 0.14%) and one pupil (0.07%) each with hyphema, eyelid ecchymosis, eyelid laceration, and subconjunctival haemorrhage. The ocular trauma occurred following unsupervised play (4, 36.40%), corporal punishment at school and at home (3, 27.30%), fight (2, 18.20%), home accident (1, 9.10%) and couching (1, 9.10%). School pupils can lose vision to preventable traumatic eye injuries both at school and at home. Measures to minimize ocular trauma both in the home and at school are advocated.

  16. Pupil Absenteeism and the Educational Psychologist

    Science.gov (United States)

    Carroll, H. C. M.

    2015-01-01

    From a review of the literature, it is concluded that (i) each form of pupil absenteeism relates to a heterogeneous group of children; (ii) because of such heterogeneity, those who are involved in assessment and intervention in relation to pupil absenteeism are faced with a demanding task; (iii) as a consequence of their education and training,…

  17. Ability of Slovakian Pupils to Identify Birds

    Science.gov (United States)

    Prokop, Pavol; Rodak, Rastislav

    2009-01-01

    A pupil's ability to identify common organisms is necessary for acquiring further knowledge of biology. We investigated how pupils were able to identify 25 bird species following their song, growth habits, or both features presented simultaneously. Just about 19% of birds were successfully identified by song, about 39% by growth habit, and 45% of…

  18. Principals' Pupil Control Behavior and School Robustness.

    Science.gov (United States)

    Smedley, Stanley R.; Willower, Donald J.

    1981-01-01

    A survey of 3,100 students, teachers, and principals in 47 elementary and secondary schools in the Middle Atlantic region, using the Pupil Control Behavior Form, revealed a positive association between principals' humanistic pupil control behavior and schools'"robustness" (the degree of meaning and excitement students find in school).…

  19. Turkish Primary School Pupils' Views on Punishment

    Science.gov (United States)

    Aydin, Bahri

    2010-01-01

    Teachers meet with unwanted behavior when they are acting as facilitators of the learning process and they resort to certain tactics to deal with them. One of these tactics is punishment. This study aimed to identify the views held by Turkish primary school pupils on punishment. According to the results of the study, pupils were punished for…

  20. Pupils' involvement in ecological activities in school

    Directory of Open Access Journals (Sweden)

    Stanišić Jelena

    2009-01-01

    Full Text Available Ecological education gains an increasing importance in the moment when ecological crisis acquires increasingly larger proportions. Education is one of the most powerful social means in fighting problems and challenges of the future. This paper presents the results of the research referring to pupils' attitudes with respect to the activities they prefer to be involved in, the independent variables their readiness for involvement depends on, as well as the relation between the knowledge possessed by pupils and their readiness to be involved in ecological activities. Research was conducted on the sample of 284 pupils in the eighth grade of primary school in urban and rural area and polluted and unpolluted environment. The results indicate that pupils find more interesting the activities taking place in nature, those where they are immediate participants and those where they have a subjective feeling that they are doing something to protect the environment. Besides, the results show that girls from both samples and pupils from rural area are more ready to get involved in ecological activities. Living in polluted or unpolluted environment is not a statistically significant variable which would influence the readiness of pupils to get involved in these activities. As the most interesting result of this research, we consider the finding that a higher level of pupils' ecological knowledge and living in polluted environment do not guarantee higher readiness of pupils to get involved in the activities of environment protection.

  1. Analysis of pupil and corneal wave aberration data supplied by the SN CT 1000 topography system

    Science.gov (United States)

    Comastri, S. A.; Martin, G.; Pfortner, T.

    2006-11-01

    Ocular aberrations depend on pupil size and centring and the retinal image quality under natural conditions differs from that corresponding to laboratory ones. In the present article, pupil and wave aberration data supplied by the Shin Nippon CT 1000 (SN CT 1000) topography system are analysed. Two groups of eyes under natural viewing conditions are considered ((260+/-20) lux at the eye under study). The first group consists of 10 normal eyes (-1.25 to 3 D sphere; 0 to -1.75 D cylinder) of five young subjects (age between 18 and 33 years). For this group, five determinations per eye are performed and the repeatability of results is analysed. Pupil centre is displaced from corneal vertex towards the temporal region, the largest displacement being (0.5+/-0.1) mm. The variation of pupil diameter in each eye is less than 21% while the inter-subject variability is large since diameters are between (3+/-0.3) and (5.3+/-0.6) mm. Aberrations are evaluated for two different pupil sizes, the natural one and a fictitious one of 6 mm. The corneal higher-order root-mean square wavefront error (RMSHO) for a 6 mm pupil centred in the corneal vertex, averaged across all eyes, is (0.37+/-0.06) [mu]m while, considering the natural pupil diameter, the average in each eye is significantly lower, up to eight times smaller. The fourth-order spherical aberration is an important aberration in the considered eyes, its maximum value for a 6 mm pupil being (0.38+/-0.02) [mu]m. The second group consists of 24 eyes of 12 subjects (age between 25 and 68 years) such that four eyes are of normal adults (1.25 to +6 D sphere; 0 to -0.5 D cylinder), eight have astigmatisms (-5.5 to +3.25 D sphere; -1.5 to -4.5 D cylinder), six have post-refractive surgery (+0.5 to +3.5 D sphere; -0.5 to -4 D cylinder) and six have keratoconus (-9.5 to +1 D sphere; -1 to -4.5 D cylinder). For this group only one determination per eye is performed. Pupil centre is displaced from corneal vertex towards the temporal

  2. Tonic Pupil Following Traumatic Hyphema: Case Report

    Directory of Open Access Journals (Sweden)

    Şaban Gönül

    2013-04-01

    Full Text Available A 7-year-old girl was admitted to our clinic after crash injury with air gun pellet in her right eye. There was an intense anterior chamber reaction and hyphema on the biomicroscopic examination. During the control examination after treatment of hyphema including cyclopentolate 1%, prednisolone acetate 1% and lomefloxacin 0.3%, anisocoria and mydriasis in the right eye were observed and the difference between both pupils was less in darkness. The case was diagnosed as tonic pupil following trauma, and diluted pilocarpine 0.125% test was performed. On diluted pilocarpine test, right pupil responded excessively to pilocarpine compared with the other pupil. As in our case, in cases with anisocoria following blunt trauma to orbit, tonic pupil should be keep in mind. (Turk J Ophthalmol 2013; 43: 132-4

  3. 78 FR 66950 - Trade Barriers That U.S. Small and Medium-Sized Enterprises Perceive as Affecting Exports to the...

    Science.gov (United States)

    2013-11-07

    ... COMMISSION Trade Barriers That U.S. Small and Medium-Sized Enterprises Perceive as Affecting Exports to the... ). Persons with mobility impairments who will need special assistance in gaining access to the Commission... prepare a report that catalogs trade barriers that U.S. small and medium-sized enterprises (SMEs)...

  4. Estimation of mental effort in learning visual search by measuring pupil response.

    Directory of Open Access Journals (Sweden)

    Tatsuto Takeuchi

    Full Text Available Perceptual learning refers to the improvement of perceptual sensitivity and performance with training. In this study, we examined whether learning is accompanied by a release from mental effort on the task, leading to automatization of the learned task. For this purpose, we had subjects conduct a visual search for a target, defined by a combination of orientation and spatial frequency, while we monitored their pupil size. It is well known that pupil size reflects the strength of mental effort invested in a task. We found that pupil size increased rapidly as the learning proceeded in the early phase of training and decreased at the later phase to a level half of its maximum value. This result does not support the simple automatization hypothesis. Instead, it suggests that the mental effort and behavioral performance reflect different aspects of perceptual learning. Further, mental effort would be continued to be invested to maintain good performance at a later stage of training.

  5. Size Matters a Lot: Drought-Affected Italian Oaks Are Smaller and Show Lower Growth Prior to Tree Death

    Science.gov (United States)

    Colangelo, Michele; Camarero, Jesús J.; Borghetti, Marco; Gazol, Antonio; Gentilesca, Tiziana; Ripullone, Francesco

    2017-01-01

    Hydraulic theory suggests that tall trees are at greater risk of drought-triggered death caused by hydraulic failure than small trees. In addition the drop in growth, observed in several tree species prior to death, is often interpreted as an early-warning signal of impending death. We test these hypotheses by comparing size, growth, and wood-anatomy patterns of living and now-dead trees in two Italian oak forests showing recent mortality episodes. The mortality probability of trees is modeled as a function of recent growth and tree size. Drift-diffusion-jump (DDJ) metrics are used to detect early-warning signals. We found that the tallest trees of the anisohydric Italian oak better survived drought contrary to what was predicted by the theory. Dead trees were characterized by a lower height and radial-growth trend than living trees in both study sites. The growth reduction of now-dead trees started about 10 years prior to their death and after two severe spring droughts during the early 2000s. This critical transition in growth was detected by DDJ metrics in the most affected site. Dead trees were also more sensitive to drought stress in this site indicating different susceptibility to water shortage between trees. Dead trees did not form earlywood vessels with smaller lumen diameter than surviving trees but tended to form wider latewood vessels with a higher percentage of vessel area. Since living and dead trees showed similar competition we did not expect that moderate thinning and a reduction in tree density would increase the short-term survival probability of trees. PMID:28270816

  6. Modeling the transmission and thermal emission in a pupil image behind the Keck II adaptive optics system

    Science.gov (United States)

    Arriaga, Pauline; Fitzgerald, Michael P.; Lyke, James E.; Campbell, Randall D.; Wizinowich, Peter L.; Adkins, Sean M.; Matthews, Keith Y.

    2016-08-01

    The design and performance of astronomical instruments depend critically on the total system throughput as well as the background emission from the sky and instrumental sources. In designing a pupil stop for background- limited imaging, one seeks to balance throughput and background rejection to optimize measurement signal-to-noise ratios. Many sources affect transmission and emission in infrared imaging behind the Keck Observatory's adaptive optics systems, such as telescope segments, segment gaps, secondary support structure, and AO bench optics. Here we describe an experiment, using the pupil-viewing mode of NIRC2, to image the pupil plane as a function of wavelength. We are developing an empirical model of throughput and background emission as a function of position in the pupil plane. This model will be used in part to inform the optimal design of cold pupils in future instruments, such as the new imaging camera for OSIRIS.

  7. Study on the Availability Opening Size of Throttle and Affection to the Velocity Characteristic of Shock Absorber

    Institute of Scientific and Technical Information of China (English)

    ZHOU Chang-cheng; ZHENG Zhi-yun; GU Liang; CHEN Yi-jie

    2007-01-01

    Based on the solution of the governing differential equation for deformation of throttle slice while satisfying required boundary conditions,the coefficient (Gr) and an analytical formula for computing the deformation of throttle slice is presented through equivalency transformation,which is a concise,accurate and practical method for throttle slice design and characteristic analysis.Researched the deformation at any radius,compared with ANSYS FEA software by the simulation analysis,the availability opening size of throttle that was defined by the deformation at the valve mouth radius is studied. The affection of valve mouth radius to the damper characteristic is analyzed.Tests are made for the damper characteristic,compared with simulation results,it is shown that Gr method is an accurate computation method for computing the deformation of throttle slice at valve mouth radius,suitible to use in the damper design,analysis,and verification.The deformation at mouth radius could not be replaced with the outside radius.

  8. Reducing resin content and board density without adversely affecting the mechanical properties of particleboard through controlling particle size

    Institute of Scientific and Technical Information of China (English)

    Mohammad Arabi; Mehdi Faezipour; Heydar Gholizadeh

    2011-01-01

    Density and resin content are two factors that have a significant effect on the production cost of wood composite.However,particle size affects resin content and density,which suggests that the interaction of these three factors can be manipulated to reduce the board density and resin content of particleboard without adversely influencing its mechai cal properties.Some mathematical functional forms based on resin content,board density and slenderness ratio were regressed and an appropriate form was chosen.According to analysis of the results using SHAZAM 9 software,the exponential function best fit the experimental data.Finally,"indifference curves" of mechanical properties were illustrated and analyzed.The results indicated that negative effects of density or resin content reduction on mechanical properties could be compensated for by controlling particles' slenderness ratio.Interestingly,increases in slenderness ratio compensated for the negative effects of decreases in resin content or board density on module of rupture (MOR) and module of elasticity (MOE).Moreover,this "compensation ratio" intensified as resin content or density decreased and/or as the MOR or MOE increased.On the other hand,reduction in slenderness ratio indicated a complementary effect on reducing internal bond (IB) strength,a result of decresses in resin content or density.Moreover,this "complementary ratio" was intensified as resin content or density decreased and/or as IB strength increased.

  9. Big wigs and small wigs: Time, sex, size and shelter affect cohabitation in the maritime earwig (Anisolabis maritima).

    Science.gov (United States)

    Hack, Nicole L; Iyengar, Vikram K

    2017-01-01

    Animal aggregations can occur for a variety of abiotic factors, such as resource limitation, or biotic factors, including group foraging and protection from predators. In our study, we examined whether time, sex, body size or shelter availability affected aggregation behavior of the maritime earwig, Anisolabis maritima (Order Dermaptera), an insect found globally at high densities under driftwood. Specifically, we monitored the distribution of two individuals in arenas with either two shelters (no habitat limitation) or one shelter (habitat limitation) to determine their propensity for cohabitation at times of peak activity and times of quiescence. Females, whose high levels of aggression are often associated with maternal care, were particularly averse to cohabitation, whereas males were generally more tolerant of other earwigs. Females initially preferred not to cohabitate when placed with a male, but were more tolerant of cohabitation later, regardless of the number of shelters. Same-sex pairs, on the other hand, were less likely to cohabitate with only one shelter present, but males were again more tolerant of conspecifics than females regardless of habitat limitation. When competition for one shelter did not lead to cohabitation, the lone occupant was more likely to be the larger individual in same-sex trials and females in mixed-sex trials. Understanding the tolerance for close proximity under these varying conditions may provide insight into aggregative behavior and spatial distribution patterns in the maritime earwig.

  10. Music chills: The eye pupil as a mirror to music's soul.

    Science.gov (United States)

    Laeng, Bruno; Eidet, Lise Mette; Sulutvedt, Unni; Panksepp, Jaak

    2016-08-01

    This study evaluated whether music-induced aesthetic "chill" responses, which typically correspond to peak emotional experiences, can be objectively monitored by degree of pupillary dilation. Participants listened to self-chosen songs versus control songs chosen by other participants. The experiment included an active condition where participants made key presses to indicate when experiencing chills and a passive condition (without key presses). Chills were reported more frequently for self-selected songs than control songs. Pupil diameter was concurrently measured by an eye-tracker while participants listened to each of the songs. Pupil size was larger within specific time-windows around the chill events, as monitored by key responses, than in comparison to pupil size observed during 'passive' song listening. In addition, there was a clear relationship between pupil diameter within the chills-related time-windows during both active and passive conditions, thus ruling out the possibility that chills-related pupil dilations were an artifact of making a manual response. These findings strongly suggest that music chills can be visible in the moment-to-moment changes in the size of pupillary responses and that a neuromodulatory role of the central norepinephrine system is thereby implicated in this phenomenon.

  11. Change in efficiency of aspheric intraocular lenses based on pupil diameter.

    Science.gov (United States)

    Eom, Youngsub; Yoo, Eunjoo; Kang, Su-Yeon; Kim, Hyo-Myung; Song, Jong-Suk

    2013-03-01

    To measure the effect of spherical aberration correction by aspheric intraocular lenses (IOLs) based on pupil diameter, and to determine the minimum pupil diameter for each aspheric IOL. Retrospective cross-sectional study. Eight-six patients (169 eyes) who were implanted with a HOYA AF-1 NY-60 (HOYA Corporation) or Tecnis ZCB00 1-piece IOL (Abbott Medical Optics Inc) were enrolled. Ocular, corneal, and internal spherical aberrations were measured at the 1-month postoperative visit using the Wavefront Analyzer KR-1W (Topcon). Minimum pupil diameter, which is required for each aspheric IOL to be effective, was calculated using a regression equation. The mean value of internal spherical aberration of the Tecnis ZCB00 group (-0.09 ± 0.094 μm) was lower than that of the HOYA NY-60 group (-0.05 ± 0.072 μm) (P = .005). The original negative spherical aberrations of the HOYA NY-60 (-0.18 μm) were measured at a pupil diameter of 5.6 mm, and for the Tecnis ZCB00 (-0.27 μm) at a pupil diameter of 6.1 mm. The aspheric IOL efficiency dropped to 0% when the pupil diameter was 3.47 mm for the Tecnis ZCB00 group and 3.71 mm for the HOYA NY-60 group. When the pupil diameters of patients are smaller than 3.4 mm for the Tecnis ZCB00 and 3.7 mm for the HOYA NY-60, the spherical aberration correction using these aspheric IOLs seems to be ineffective. Approximately 10% of the eyes showed smaller pupil size than the minimum effective diameter under mesopic conditions. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Assessing Visual Delays using Pupil Oscillations

    Science.gov (United States)

    Mulligan, Jeffrey B.

    2012-01-01

    Stark (1962) demonstrated vigorous pupil oscillations by illuminating the retina with a beam of light focussed to a small spot near the edge of the pupil. Small constrictions of the pupil then are sufficient to completely block the beam, amplifying the normal relationship between pupil area and retinal illuminance. In addition to this simple and elegant method, Stark also investigated more complex feedback systems using an electronic "clamping box" which provided arbitrary gain and phase delay between a measurement of pupil area and an electronically controlled light source. We have replicated Stark's results using a video-based pupillometer to control the luminance of a display monitor. Pupil oscillations were induced by imposing a linear relationship between pupil area and display luminance, with a variable delay. Slopes of the period-vs-delay function for 3 subjects are close to the predicted value of 2 (1.96-2.39), and the implied delays range from 254 to 376 508 to 652 milliseconds. Our setup allows us to extend Stark's work by investigating a broader class of stimuli.

  13. Secondary school pupils' perceptions of physics

    Science.gov (United States)

    Barmby, Patrick; Defty, Neil

    2006-11-01

    This paper describes the analysis of data collected by Durham University’s YELLIS project, over the period of 1999 to 2004. Included in this data was the degree to which pupils in England at the end of their secondary education ‘liked’ or ‘disliked’ different subjects, and their expected examination grades in these subjects. The authors’ study focused on the perceptions of pupils in the science subjects of biology, chemistry and physics. Using the available data, they were able to analyse the perceptions of a large number of pupils (e.g. 9827 pupils in 2004) who took examinations in the separate sciences. The study found that physics was perceived as the least popular science, particularly by female pupils. We also found that the expected grade in a particular science subject correlated quite strongly (Spearman’s rho of around 0.5) with the liking of that subject. These expected grades were found to be the lowest in physics, again particularly for female pupils. The authors therefore concluded that in order to redress the gender imbalance in physics, they need to tackle this problem that physics is perceived as difficult by female pupils.

  14. Effective pupil dilatation with a mixture of 0.75% tropicamide and 2.5% phenylephrine: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Trinavarat Adisak

    2009-01-01

    Full Text Available Purpose: To compare the efficacy in pupil dilatation between a mixture containing 0.75% tropicamide and 2.5% phenylephrine and the alternate application of 1% tropicamide and 10% phenylephrine eye drops. Material and Methods : Patients requiring pupil dilatation were randomized to receive one drop of the mixture every 10 min for four times or our standard application of one drop of 1% tropicamide alternating with one drop of 10% phenylephrine every 10 min for two cycles. Pupil size was measured under bright light with the pupil gauge before, and every 5 min after initial application for 40 min. Application of the drops was discontinued once the pupil diameter reached 7 mm. Blood pressure and pulse rate were monitored every 15 min. Results: Of 40 patients (age 57.3±10.9 years, range 35-70 years, 22 were randomized into the mixture group and 18 into the alternate drug group. Baseline pupil sizes were 1.7±0.5 mm in the mixture group and 1.8±0.4 mm in the alternate drug group. The pupils were successfully dilated to 7 mm within 40 min in 17 patients of the mixture group compared to seven patients in the alternate drug group ( P =0.004, Log Rank test. The mean pupil sizes at 40 min were 6.6±0.8 and 6.0±0.9 mm in the mixture and alternate drug groups respectively ( P =0.050, t-test. Blood pressure and pulse rate were stable and similar in both groups. Conclusions: The mixture of 0.75% tropicamide and 2.5% phenylephrine is superior to our standard application of 1% tropicamide alternating with 10% phenylephrine. It provides faster and more successful pupil dilatation within 40 min.

  15. Two-zone pupil filters

    Science.gov (United States)

    Sheppard, Colin J. R.; Campos, Juan; Escalera, Juan C.; Ledesma, Silvia

    2008-03-01

    The performance of pupil filters consisting of two zones each of constant complex amplitude transmittance is investigated. For filters where the transmittance is real, different classes of potentially useful filter are identified and optimized. These include leaky filters with an inner zone of low amplitude transmittance, pure phase filters with phase change of π, and equal area filters. The first of these minimizes the relative power in the outer rings for a given axial resolution, the second maximizes the Strehl ratio for a given transverse resolution, and the third minimizes the relative power in the outer rings for a given transverse resolution. Complex filters can give an axially shifted maximum in intensity: the performance parameters calculated relative to the true focus are investigated for some different classes of filter, but filters with phase change not equal to π are found to give inferior performance to the real value filters.

  16. Symmetry properties with pupil phase-filters.

    Science.gov (United States)

    Ledesma, Silvia; Campos, J; Escalera, J; Yzuel, M

    2004-05-31

    Pupil filters can modify the three dimensional response of an optical system. In this paper, we study different pupil symmetries that produce a predictable image behavior. We show that different pupil-filters that satisfy certain symmetry conditions can produce axial responses which are either identical or mirror reflected. We also establish the differences in the symmetry properties between amplitude-only filters and phase-only filters. In particular, we are interested in phase filters that produce transverse superresolution with axial superresolution or high depth of focus.

  17. Combining Blink, Pupil, and Response Time Measures in a Concealed Knowledge Test

    Directory of Open Access Journals (Sweden)

    Travis eSeymour

    2013-02-01

    Full Text Available The response time (RT based Concealed Knowledge Test (CKT has been shown to accurately detect participants’ knowledge of mock-crime related information. Tests based on ocular measures such as pupil size and blink rate have sometimes resulted in poor classification, or lacked detailed classification analyses. The present study examines the fitness of multiple pupil and blink related responses in the CKT paradigm. To maximize classification efficiency, participants’ concealed knowledge was assessed using both individual test measures and combinations of test measures. Results show that individual pupil-size, pupil-slope, and pre-response blink-rate measures produce efficient classifications. Combining pupil and blink measures yielded more accuracy classifications than individual ocular measures. Although RT-based tests proved efficient, combining RT with ocular measures had little incremental benefit. It is argued that covertly assessing ocular measures during RT-based tests may guard against effective countermeasure use in applied settings. A compound classification procedure was used to categorize individual participants and yielded high hit rates and low false-alarm rates without the need for adjustments between test paradigms or subject populations. We conclude that with appropriate test paradigms and classification analyses, ocular measures may prove as effective as other indices, though additional research is needed.

  18. Counselling Needs of Pupils with Special Educational Needs and Disabilities in the Greater Accra Region of Ghana: Implications for Inclusive Education in Ghana

    Science.gov (United States)

    Ocansey, S. K.; Gyimah, E. K.

    2016-01-01

    In this fast changing world, pupils all over the world have developed severe social and psychological needs that affect their interactions with others and subsequently, the achievement of their life goals. Essentially, the social and psychological needs of school pupils have manifested in diverse mal-adjusted behaviours that hinder their academic…

  19. Pasting properties and (chemical) fine structure of acetylated yellow pea starch is affected by acetylation reagent type and granule size

    NARCIS (Netherlands)

    Huang, J.; Schols, H.A.; Jin, Z.; Sulmann, E.; Voragen, A.G.J.

    2007-01-01

    Yellow pea starch was fractionated into small and large size granule fractions and then modified with acetic anhydride and vinyl acetate (acetylation after sieving) or first acetylated in the same way and then fractionated into small and large size fractions (acetylation before sieving). Acetylation

  20. Nutrient demand interacts with legume particle length to affect digestion responses and rumen pool sizes in dairy cows.

    Science.gov (United States)

    Kammes, K L; Ying, Y; Allen, M S

    2012-05-01

    Effects of legume particle length on dry matter intake (DMI), milk production, ruminal fermentation and pool sizes, and digestion and passage kinetics, and the relationship of these effects with preliminary DMI (pDMI) were evaluated using 13 ruminally and duodenally cannulated Holstein cows in a crossover design with a 14-d preliminary period and two 19-d treatment periods. During the preliminary period, pDMI of individual cows ranged from 22.8 to 32.4 kg/d (mean=26.5 kg/d) and 3.5% fat-corrected milk yield ranged from 22.9 to 62.4 kg/d (mean=35.1 kg/d). Experimental treatments were diets containing alfalfa silage chopped to (1) 19 mm (long cut, LC) or (2) 10 mm (short cut, SC) theoretical length of cut as the sole forage. Alfalfa silages contained approximately 43% neutral detergent fiber (NDF); diets contained approximately 47% forage and 20% forage NDF. Preliminary DMI, an index of nutrient demand, was determined during the last 4 d of the preliminary period, when cows were fed a common diet, and used as a covariate. Main effects of legume particle length and their interaction with pDMI were tested by ANOVA. Alfalfa particle length and its interaction with pDMI did not affect milk yield or rumen pH. The LC diet decreased milk fat concentration more per kilogram of pDMI increase than the SC diet and increased yields of milk fat and fat-corrected milk less per kilogram of pDMI increase than the SC diet, resulting in a greater benefit for LC at low pDMI and for SC at high pDMI. The LC diet tended to decrease DMI compared with the SC diet. Ruminal digestion and passage rates of feed fractions did not differ between LC and SC and were not related to level of intake. The LC diet tended to decrease the rate of ruminal turnover for NDF but increased NDF rumen pools at a slower rate than the SC diet as pDMI increased. This indicated that the faster NDF turnover rate did not counterbalance the higher DMI for SC, resulting in larger NDF rumen pools for SC than LC. As p

  1. Pupil responses derived from outer and inner retinal photoreception are normal in patients with hereditary optic neuropathy.

    Science.gov (United States)

    Kawasaki, Aki; Collomb, Sylvie; Léon, Lorette; Münch, Mirjam

    2014-03-01

    We compared the pupil responses originating from outer versus inner retinal photoreception between patients with isolated hereditary optic neuropathy (HON, n = 8) and healthy controls (n = 8). Three different testing protocols were used. For the first two protocols, a response function of the maximal pupil contraction versus stimulus light intensity was generated and the intensity at which half of the maximal pupil contraction, the half-max intensity, was determined. For the third protocol, the pupil size after light offset, the re-dilation rate and re-dilation amplitude were calculated to assess the post-light stimulus response. Patients with HON had bilateral, symmetric optic atrophy and significant reduction of visual acuity and visual field compared to controls. There were no significant mean differences in the response curve and pupil response parameters that reflect mainly rod, cone or melanopsin activity between patients and controls. In patients, there was a significant correlation between the half-max intensity of the red light sequence and visual field loss. In conclusion, pupil responses derived from outer or inner retinal photoreception in HON patients having mild-to moderate visual dysfunction are not quantitatively different from age-matched controls. However, an association between the degree of visual field loss and the half-max intensity of the cone response suggests that more advanced stages of disease may lead to impaired pupil light reflexes.

  2. A Study of Teacher-Pupil and Pupil-Pupil Interactional Differences Between Inquiry Centered Science and Traditional Science in Elementary Schools.

    Science.gov (United States)

    Rains, Ohren Willis

    Reported is a study of teacher-pupil and pupil-pupil interactional differences between a traditional instruction method and an inquiry-centered learning method for 18 science classes at the fourth and fifth grade levels. Nine classes were assigned to the experimental group, and the remaining nine classes received a traditional program. Classroom…

  3. THE SIZE AND SURFACE COATING OF NANOSILVER DIFFERENTIALLY AFFECTS BIOLOGICAL ACTIVITY IN BLOOD BRAIN BARRIER (RBEC4) CELLS.

    Science.gov (United States)

    Linking the physical properties of nanoparticles with differences in their biological activity is critical for understanding their potential toxicity and mode of action. The influence of aggregate size, surface coating, and surface charge on nanosilver's (nanoAg) movement through...

  4. 7 CFR 4290.760 - How a change in size or activity of a Portfolio Concern affects the RBIC and the Portfolio Concern.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false How a change in size or activity of a Portfolio Concern affects the RBIC and the Portfolio Concern. 4290.760 Section 4290.760 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE SERVICE AND RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL...

  5. The pupil as an indicator of unconscious memory: Introducing the pupil priming effect.

    Science.gov (United States)

    Gomes, Carlos Alexandre; Montaldi, Daniela; Mayes, Andrew

    2015-06-01

    We explored whether object behavioral priming and pupil changes occur in the absence of recognition memory. Experiment 1 found behavioral priming for unrecognized objects (Ms) regardless of whether they had been encoded perceptually or conceptually. Using the same perceptual encoding task, Experiment 2 showed greater pupil dilation for Ms than for correct rejections of unstudied objects (CRs) when reaction times were matched. In Experiment 3, there was relatively less pupil dilation for Ms than for similarly matched CRs when objects had been encoded conceptually. Mean/peak pupil dilation for CRs, but not Ms, increased in Experiment 3, in which novelty expectation was also reduced, and the pupillary time course for both Ms and CRs was distinct in the two experiments. These findings indicate that both behavioral and pupil memory occur for studied, but unrecognized stimuli, and suggest that encoding and novelty expectation modulate pupillary memory responses.

  6. Lateral pupil alignment tolerance in peripheral refractometry.

    Science.gov (United States)

    Fedtke, Cathleen; Ehrmann, Klaus; Ho, Arthur; Holden, Brien A

    2011-05-01

    To investigate the tolerance to lateral pupil misalignment in peripheral refraction compared with central refraction. A Shin-Nippon NVision-K5001 open-view auto-refractor was used to measure central and peripheral refraction (30° temporal and 30° nasal visual field) of the right eyes of 10 emmetropic and 10 myopic participants. At each of the three fixation angles, five readings were recorded for each of the following alignment positions relative to pupil center: centrally aligned, 1 and 2 mm temporally aligned, and 1 and 2 mm nasally aligned. For central fixation, increasing dealignment from pupil center produced a quadratic decrease (r ≥ 0.98, p < 0.04) in the refractive power vectors M and J180 which, when interpolated, reached clinical significance (i.e., ≥ 0.25 diopter for M and ≥ 0.125 diopter for J180 and J45) for an alignment error of 0.79 mm or greater. M and J180 as measured in the 30° temporal and 30° nasal visual field led to a significant linear correlation (r ≥ 0.94, p < 0.02) as pupil dealignment gradually changed from temporal to nasal. As determined from regression analysis, a pupil alignment error of 0.20 mm or greater would introduce errors in M and J180 that are clinically significant. Tolerance to lateral pupil alignment error decreases strongly in the periphery compared with the greater tolerance in central refraction. Thus, precise alignment of the entrance pupil with the instrument axis is critical for accurate and reliable peripheral refraction.

  7. Visual acuity evaluated by pattern-reversal visual-evoked potential is affected by check size/visual angle

    Institute of Scientific and Technical Information of China (English)

    Xiping Chen; Qianqian Li; Xiaoqin Liu; Li Yang; Wentao Xia; Luyang Tao

    2012-01-01

    Objective To systemically explore the range of visual angles that affect visual acuity,and to establish the relationship between the P 1 component (peak latency ~100 ms) of the pattern-reversal visual-evoked potential (PRVEP) and the visual acuity at particular visual angles.Methods Two hundred and ten volunteers were divided into seven groups,according to visual acuity as assessed by the standard logarithmic visual acuity chart (SLD-II).For each group,the PRVEP components were elicited in response to visual angle presentations at 8°,4°,2°,1 °/60′,30′,15′,and 7.5′,in the whiteblack chess-board reversal mode with a contrast level of 100% at a frequency of 2 Hz.Visual stimuli were presented monocularly,and 200 presentations were averaged for each block of trials.The early and stable component P1 was recorded at the mid-line of the occipital region (Oz) and analyzed with SPSS 13.00.Results (1) Oz had the maximum P1 amplitude;there was no significant difference between genders or for interocular comparison in normal controls and subjects with optic myopia.(2) The P1 latency decreased slowly below 30′,then increased rapidly.The P1 amplitude initially increased with check size,and was maximal at ~1° and ~30′.(3) The P1 latency in the group with visual acuity ≤0.2 was significantly different at 8°,15′ and 7.5′,while the amplitude differed at all visual angles,compared with the group with normal vision.Diferences in P1 for the groups with 0.5 and 0.6 acuity were only present at visual angles <1°.(4) Regression analysis showed that the P 1 latency and amplitude were associated with visual acuity over the full range of visual angles.There was a moderate correlation at visual angles <30′.Regression equations were calculated for the P1 components and visual acuity,based on visual angle.Conclusion (1) Visual angle should be taken into consideration when exploring the function of the visual pathway,especially visual acuity.A visual angle

  8. Body size affects the predatory interactions between introduced American Bullfrogs (Rana catesbeiana) and native anurans in China: An experimental study

    Science.gov (United States)

    Wang, Y.; Guo, Z.; Pearl, C.A.; Li, Y.

    2007-01-01

    Introduced American Bullfrogs (Rana catesbeiana) have established breeding populations in several provinces in China since their introduction in 1959. Although Bullfrogs are viewed as a potentially important predator of Chinese native anurans, their impacts in the field are difficult to quantify. We used two experiments to examine factors likely to mediate Bullfrog predation on native anurans. First, we examined effects of Bullfrog size and sex on daily consumption of a common Chinese native (Rana limnocharis). Second, we examined whether Bullfrogs consumed similar proportions of four Chinese natives: Black-Spotted Pond Frog (Rana nigromaculata), Green Pond Frog (Rana plancyi plancyi), Rice Frog (R. limnocharis), and Zhoushan Toad (Bufo bufo gargarizans). We found that larger Rana catesbeiana consumed more R. limnocharis per day than did smaller R. catesbeiana, and that daily consumption of R. limnocharis was positively related to R. catesbeiana body size. When provided with adults of four anurans that differed significantly in body size, R. catesbeiana consumed more individuals of the smallest species (R. limnocharis). However, when provided with similarly sized juveniles of the same four species, R. catesbeiana did not consume any species more than expected by chance. Our results suggest that body size plays an important role in the predatory interactions between R. catesbeiana and Chinese native anurans and that, other things being equal, smaller species and individuals are at greater risk of predation by R. catesbeiana. Copyright 2007 Society for the Study of Amphibians and Reptiles.

  9. Moisture content and particle size of dehydrated egg yolk affect lipid and cholesterol extraction using supercritical carbon dioxide.

    Science.gov (United States)

    Froning, G W; Wehling, R L; Cuppett, S; Niemann, L

    1998-11-01

    Egg yolk was spray-dried under conditions to produce a small particle size powder and a large particle size powder. Particle size was determined using a Nikon Optiophot microscope. Spray-dried egg yolk was also adjusted to various moisture levels as follows: control (2 to 4% moisture), 7% moisture, and 12% moisture. Supercritical carbon dioxide extraction (SCE) of each of these moisture treatments at 45 C/306 atm using 30 g CO2/g of sample was completed. For the particle size study, 45 g CO2/g of sample at 45 C/306 atm was utilized. Particle size exhibited a significant effect on cholesterol and lipids extracted using SCE. As moisture content of dried egg yolk increased to 7%, there was a significant increase in lipids extracted using supercritical carbon dioxide. Moisture content had no significant effect on cholesterol extraction. After extracting SCE higher moisture spray-dried egg yolk, sponge cake volume was significantly reduced compared to that of the control. The reduced sponge cake volume may be due to protein denaturation.

  10. Body attributes of both parents jointly affect offspring sex allocation in a socially monogamous, size-monomorphic passerine

    Institute of Scientific and Technical Information of China (English)

    Xin LU; Xianhai ZENG; Bo DU

    2013-01-01

    Theory predicts that because males are more variable in reproductive success than females,a mother should produce more sons to maximize fitness return from the sex allocation if she is of high-quality (the female quality hypothesis) or mates with a high-quality male (the male quality hypothesis).While most previous studies have looked at each hypothesis,we tested both of them simultaneously in the white-rumped snowfinch Montifringilla taczanowskii,a socially monogamous,sexually monomorphic passerine where body size is a potential indicator of individual quality in intrasexual competition and territory defense.Brood sex ratios at the population level did not deviate from random expectation.Among individual broods,the proportion of sons did not depend on body size of either male or female parent,but on interaction of this trait of both parents.Further analyses revealed that brood sex ratios were independent of body size of male or female parents when their mates were smaller,but positively related with body size of male or female parents when their mates were larger.These results suggest that mechanisms underlying the two hypotheses may act jointly on offspring sex allocation.The mechanisms are expected to evolve through size-assortative mating which is often reached by sexual selection.

  11. A solid frame for the window on cognition: Modeling event-related pupil responses.

    Science.gov (United States)

    Korn, Christoph W; Bach, Dominik R

    2016-01-01

    Pupil size is often used to infer central processes, including attention, memory, and emotion. Recent research has spotlighted its relation to behavioral variables from decision-making models and to neural variables such as locus coeruleus activity and cortical oscillations. As yet, a unified and principled approach for analyzing pupil responses is lacking. Here we seek to establish a formal, quantitative forward model for pupil responses by describing them with linear time-invariant systems. Based on empirical data from human participants, we show that a combination of two linear time-invariant systems can parsimoniously explain approximately all variance evoked by illuminance changes. Notably, the model makes a counterintuitive prediction that pupil constriction dominates the responses to darkness flashes, as in previous empirical reports. This prediction was quantitatively confirmed for responses to light and darkness flashes in an independent group of participants. Crucially, illuminance- and nonilluminance-related inputs to the pupillary system are presumed to share a common final pathway, composed of muscles and nerve terminals. Hence, we can harness our illuminance-based model to estimate the temporal evolution of this neural input for an auditory-oddball task, an emotional-words task, and a visual-detection task. Onset and peak latencies of the estimated neural inputs furnish plausible hypotheses for the complexity of the underlying neural circuit. To conclude, this mathematical description of pupil responses serves as a prerequisite to refining their relation to behavioral and brain indices of cognitive processes.

  12. Influence of graphic design of the text on reading quality of pupils with dyslexia

    Directory of Open Access Journals (Sweden)

    Zikl Pavel

    2016-01-01

    Full Text Available The contribution contains research results focused on reading quality of pupils with dyslexia according to the graphic design of the text. Our aim was to prove if commonly recommended graphic text editing has a certain influence on reading speed and occurrence of mistakes of children with dyslexia. The research sample consisted of pupils with dyslexia and a control group then selected in pairs of intact pupils of 4th and 5th class of primary school (in total 150 pupils. For the purpose of data collection there had been a text used in an unfamiliar language (a nonsensical text, which corresponds to the Czech language in its structure; is a part of standardized reading test. There were four text versions prepared for the research which had been modified into frequently recommended modifications for dyslexics (increased font size, a use of bigger gaps between words and also rows, syllables highlight in words and a standard text corresponding to common reading-books. Conclusion depicts a presentation of impacts of individual texts modifications and also subjective opinions of pupils about these texts.

  13. Intermittent exposure to reduced oxygen levels affects prey size selection and consumption in swimming crab Thalamita danae Stimpson.

    Science.gov (United States)

    Shin, P K S; Cheung, P H; Yang, F Y; Cheung, S G

    2005-01-01

    Portunid crabs Thalamita danae (carapace width: 46-56 mm) were exposed to low oxygen level (4.0 mg O2 l(-1)) and hypoxia (1.5 mg O2 l(-1)) for 6 h each day with three size classes (large: 15.0-19.9 mm, medium: 10.0-14.9 mm, small: 5.0-9.9 mm) of mussels Brachidontes variabilis offered as food. Consumption rate, prey size preference, and prey handling including breaking time, handling time, eating time and prey value, were studied during the time the crabs were exposed to reduced oxygen levels and results were compared with the crabs maintained at high oxygen level (8.0 mg O2 l(-1)) throughout the experiment. Consumption of mussels from all size classes was significantly higher at high oxygen level than at reduced oxygen levels. No mussel size preference was observed for crabs exposed to 4.0 or 8.0 mg O2 l(-1) but those crabs exposed to 1.5 mg O2 l(-1) preferred medium mussels. Both breaking time and handling time increased with mussel size but did not vary with oxygen level. Prey value of each mussel consumed (mg dry wt eaten crab(-1) s(-1)) was calculated by dividing the estimated dry weight of the mussel by the observed handling time. Mean prey value varied significantly with mussel size, with values obtained for large mussels being higher than small mussels at 4.0 and 8.0 mg O2 l(-1); the effect of oxygen level, however, was insignificant. In view of portunid crabs as major predators of mussels, results may help explain dominance of mussels in eutrophic harbours in Hong Kong.

  14. Size of Ascaris suum larvae is affected by parental genotype and location in the intestine in pigs

    DEFF Research Database (Denmark)

    Nejsum, Peter; Thamsborg, Stig Milan; Jørgensen, Claus Bøttcher

    , respectively were positive for Ascaris and a total 1908, 1616 and 675 larvae were analysed for each day, respectively. Random effect models with pig included as a random variable were used to analyse the response variable length on each day. Section (1-8) and type (A, B, C and D) were included as explanatory.......001). At day 28 pi. the interaction between section and type was significant at P=0.03. In conclusion we have found preliminary evidence for a parental effect on the outcome of the size of the offspring in addition to a location-size effect, both possibly with a consequence on larvae fitness and therefore...

  15. Year 7 Pupils' Views of the Future

    Directory of Open Access Journals (Sweden)

    Ken Roberts

    2011-01-01

    Full Text Available This paper reports findings from a study among 610 Year 7 (typically age 12 pupils at 27 nonselective secondary schools in three English regions: Cornwall and Devon, London, and Greater Manchester. Data was gathered in workshops, each with 15–25 pupils, who completed questionnaires and performed individual tasks, all related to their vocational and educational aims, their ideas on what counted as success, and the main influences on their forward thinking, then discussed their answers and results. The discussions were tape recorded. Most pupils expressed robust occupational aims, and most said that they wanted to go to university. Family class did not predict levels of educational or occupational aims, but was related to the importance attached to “the job that I want to do” in the pupils' forward thinking. SAT scores did predict levels of occupational aspiration, ideas on what counted as success, and by whom and what the pupils were most influenced. These findings are interpreted to challenge the view, on which a raft of current policies are based, that social class disparities in educational and labour market outcomes are due to the intergenerational transmission of low aspirations in lower-class families and neighbourhoods. The paper concludes with an alternative model of status transmission processes in which attainments during secondary education are posited as the key intervening variable.

  16. JWST science instrument pupil alignment measurements

    Science.gov (United States)

    Kubalak, Dave; Sullivan, Joe; Ohl, Ray; Antonille, Scott; Beaton, Alexander; Coulter, Phillip; Hartig, George; Kelly, Doug; Lee, David; Maszkiewicz, Michael; Schweiger, Paul; Telfer, Randal; Te Plate, Maurice; Wells, Martyn

    2016-09-01

    NASA's James Webb Space Telescope (JWST) is a 6.5m diameter, segmented, deployable telescope for cryogenic IR space astronomy ( 40K). The JWST Observatory architecture includes the Optical Telescope Element (OTE) and the Integrated Science Instrument Module (ISIM) element that contains four science instruments (SI), including a guider. OSIM is a full field, cryogenic, optical simulator of the JWST OTE. It is the "Master Tool" for verifying the cryogenic alignment and optical performance of ISIM by providing simulated point source/star images to each of the four Science Instruments in ISIM. Included in OSIM is a Pupil Imaging Module (PIM) - a large format CCD used for measuring pupil alignment. Located at a virtual stop location within OSIM, the PIM records superimposed shadow images of pupil alignment reference (PAR) targets located in the OSIM and SI pupils. The OSIM Pupil Imaging Module was described by Brent Bos, et al, at SPIE in 2011 prior to ISIM testing. We have recently completed the third and final ISIM cryogenic performance verification test before ISIM was integrated with the OTE. In this paper, we describe PIM implementation, performance, and measurement results.

  17. Personality Characteristics and Self-Concept of Preservice Teachers Related to Their Pupil Control Orientation.

    Science.gov (United States)

    Halpin, Glennelle; And Others

    1982-01-01

    In a study of teacher trainees' personality characteristics related to pupil control, humanistically oriented educators tended to be emotionally stable, expedient, positive, imaginative, venturesome, relaxed and had high self-concepts. Authoritarian educators were more affected by feelings, conscientious, sober, practical, shy, reserved, tense and…

  18. Pupil and Staff Perceptions of Bullying in Secondary Schools: Comparing Behavioural Definitions and Their Perceived Seriousness

    Science.gov (United States)

    Maunder, Rachel E.; Harrop, Alex; Tattersall, Andrew J.

    2010-01-01

    Background: How bullying is understood by members of the school community is important because differences in definitions could result in an inconsistent approach and affect the success of intervention work. Research evidence suggests that pupils and teachers may have different interpretations of what constitutes bullying. This evidence has,…

  19. Site specific fertilization affects yield, fruit size, quality, and shelf-life of ‘Kent' mango

    Science.gov (United States)

    Site specific fertilization (SSF) defines the type and rate of fertilizer needed for individual orchards. This study presents preliminary results (2010-2011) of a medium term project to quantify the effects of SSF on yield, fruit size, quality, and shelf-life of ‘Kent’ mango. Two orchards are used f...

  20. Magnetic characterization of radio frequency heat affected micron size Fe3O4 powders: a bio-application perspective

    CSIR Research Space (South Africa)

    Roul, BK

    2009-05-01

    Full Text Available Micron size Fe3O4 powders were chemically prepared and processed by radio frequency (13.56 MHz) oxygen plasma irradiation technique at different elevated temperatures using low radio frequency (RF) power level. Low magnetic field RF superconducting...

  1. Is bigger better? Male body size affects wing-borne courtship signals and mating success in the olive fruit fly, Bactrocera oleae (Diptera: Tephritidae).

    Science.gov (United States)

    Benelli, Giovanni; Donati, Elisa; Romano, Donato; Ragni, Giacomo; Bonsignori, Gabriella; Stefanini, Cesare; Canale, Angelo

    2016-12-01

    Variations in male body size are known to affect inter- and intrasexual selection outcomes in a wide range of animals. In mating systems involving sexual signaling before mating, body size often acts as a key factor affecting signal strength and mate choice. We evaluated the effect of male size on courtship displays and mating success of the olive fruit fly, Bactrocera oleae (Diptera: Tephritidae). Wing vibrations performed during successful and unsuccessful courtships by large and small males were recorded by high-speed videos and analyzed through frame-by-frame analysis. Mating success of large and small males was investigated. The effect of male-male competition on mating success was evaluated. Male body size affected both male courtship signals and mating outcomes. Successful males showed wing-borne signals with high frequencies and short interpulse intervals. Wing vibrations displayed by successful large males during copulation attempt had higher frequencies over smaller males and unsuccessful large males. In no-competition conditions, large males achieved higher mating success with respect to smaller ones. Allowing large and small males to compete for a female, large males achieve more mating success over smaller ones. Mate choice by females may be based on selection of the larger males, able to produce high-frequency wing vibrations. Such traits may be indicative of "good genes," which under sexual selection could means good social-interaction genes, or a good competitive manipulator of conspecifics. © 2015 Institute of Zoology, Chinese Academy of Sciences.

  2. Field-isolated genotypes of Mycobacterium bovis vary in virulence and influence case pathology but do not affect outbreak size.

    Directory of Open Access Journals (Sweden)

    David M Wright

    Full Text Available Strains of many infectious agents differ in fundamental epidemiological parameters including transmissibility, virulence and pathology. We investigated whether genotypes of Mycobacterium bovis (the causative agent of bovine tuberculosis, bTB differ significantly in transmissibility and virulence, combining data from a nine-year survey of the genetic structure of the M. bovis population in Northern Ireland with detailed records of the cattle population during the same period. We used the size of herd breakdowns as a proxy measure of transmissibility and the proportion of skin test positive animals (reactors that were visibly lesioned as a measure of virulence. Average breakdown size increased with herd size and varied depending on the manner of detection (routine herd testing or tracing of infectious contacts but we found no significant variation among M. bovis genotypes in breakdown size once these factors had been accounted for. However breakdowns due to some genotypes had a greater proportion of lesioned reactors than others, indicating that there may be variation in virulence among genotypes. These findings indicate that the current bTB control programme may be detecting infected herds sufficiently quickly so that differences in virulence are not manifested in terms of outbreak sizes. We also investigated whether pathology of infected cattle varied according to M. bovis genotype, analysing the distribution of lesions recorded at post mortem inspection. We concentrated on the proportion of cases lesioned in the lower respiratory tract, which can indicate the relative importance of the respiratory and alimentary routes of infection. The distribution of lesions varied among genotypes and with cattle age and there were also subtle differences among breeds. Age and breed differences may be related to differences in susceptibility and husbandry, but reasons for variation in lesion distribution among genotypes require further investigation.

  3. Threat but not arousal narrows attention: Evidence from pupil dilation and saccade control

    Directory of Open Access Journals (Sweden)

    Henk eVan Steenbergen

    2011-10-01

    Full Text Available It has been shown that negative affect causes attentional narrowing. According to Easterbrook’s (1959 influential hypothesis this effect is driven by the withdrawal motivation inherent to negative emotions and might be related to increases in arousal. We investigated whether valence-unspecific increases in physiological arousal, as measured by pupil dilation, could account for attentional narrowing effects in a cognitive control task. Following the presentation of a negative, positive, or neutral picture, participants performed a saccade task with a prosaccade versus an antisaccade instruction. The reaction time difference between pro- and antisaccades was used to index attentional selectivity, and while pupil diameter was used as an index of physiological arousal. Pupil dilation was observed for both negative and positive pictures, which indicates increased physiological arousal. However, increased attentional selectivity was only observed following negative pictures. Our data show that motivational intensity effects on attentional narrowing can occur independently of physiological arousal effects.

  4. The Eyes Have It: Sex and Sexual Orientation Differences in Pupil Dilation Patterns

    Science.gov (United States)

    Rieger, Gerulf; Savin-Williams, Ritch C.

    2012-01-01

    Recent research suggests profound sex and sexual orientation differences in sexual response. These results, however, are based on measures of genital arousal, which have potential limitations such as volunteer bias and differential measures for the sexes. The present study introduces a measure less affected by these limitations. We assessed the pupil dilation of 325 men and women of various sexual orientations to male and female erotic stimuli. Results supported hypotheses. In general, self-reported sexual orientation corresponded with pupil dilation to men and women. Among men, substantial dilation to both sexes was most common in bisexual-identified men. In contrast, among women, substantial dilation to both sexes was most common in heterosexual-identified women. Possible reasons for these differences are discussed. Because the measure of pupil dilation is less invasive than previous measures of sexual response, it allows for studying diverse age and cultural populations, usually not included in sexuality research. PMID:22870196

  5. Suzuki Meets Polya: Teaching Mathematics to Young Pupils.

    Science.gov (United States)

    Hazlewood, Donald G.; And Others

    1989-01-01

    Describes how Suzuki's methods of teaching young pupils to play the violin can be combined with Polya's ideas on problem solving to teach mathematics to elementary school pupils. Six references are listed. (YP)

  6. Adaptive optics scanning ophthalmoscopy with annular pupils.

    Science.gov (United States)

    Sulai, Yusufu N; Dubra, Alfredo

    2012-07-01

    Annular apodization of the illumination and/or imaging pupils of an adaptive optics scanning light ophthalmoscope (AOSLO) for improving transverse resolution was evaluated using three different normalized inner radii (0.26, 0.39 and 0.52). In vivo imaging of the human photoreceptor mosaic at 0.5 and 10° from fixation indicates that the use of an annular illumination pupil and a circular imaging pupil provides the most benefit of all configurations when using a one Airy disk diameter pinhole, in agreement with the paraxial confocal microscopy theory. Annular illumination pupils with 0.26 and 0.39 normalized inner radii performed best in terms of the narrowing of the autocorrelation central lobe (between 7 and 12%), and the increase in manual and automated photoreceptor counts (8 to 20% more cones and 11 to 29% more rods). It was observed that the use of annular pupils with large inner radii can result in multi-modal cone photoreceptor intensity profiles. The effect of the annular masks on the average photoreceptor intensity is consistent with the Stiles-Crawford effect (SCE). This indicates that combinations of images of the same photoreceptors with different apodization configurations and/or annular masks can be used to distinguish cones from rods, even when the former have complex multi-modal intensity profiles. In addition to narrowing the point spread function transversally, the use of annular apodizing masks also elongates it axially, a fact that can be used for extending the depth of focus of techniques such as adaptive optics optical coherence tomography (AOOCT). Finally, the positive results from this work suggest that annular pupil apodization could be used in refractive or catadioptric adaptive optics ophthalmoscopes to mitigate undesired back-reflections.

  7. The erratic mitochondrial clock: variations of mutation rate, not population size, affect mtDNA diversity across birds and mammals.

    Science.gov (United States)

    Nabholz, Benoit; Glémin, Sylvain; Galtier, Nicolas

    2009-03-10

    During the last ten years, major advances have been made in characterizing and understanding the evolution of mitochondrial DNA, the most popular marker of molecular biodiversity. Several important results were recently reported using mammals as model organisms, including (i) the absence of relationship between mitochondrial DNA diversity and life-history or ecological variables, (ii) the absence of prominent adaptive selection, contrary to what was found in invertebrates, and (iii) the unexpectedly large variation in neutral substitution rate among lineages, revealing a possible link with species maximal longevity. We propose to challenge these results thanks to the bird/mammal comparison. Direct estimates of population size are available in birds, and this group presents striking life-history trait differences with mammals (higher mass-specific metabolic rate and longevity). These properties make birds the ideal model to directly test for population size effects, and to discriminate between competing hypotheses about the causes of substitution rate variation. A phylogenetic analysis of cytochrome b third-codon position confirms that the mitochondrial DNA mutation rate is quite variable in birds, passerines being the fastest evolving order. On average, mitochondrial DNA evolves slower in birds than in mammals of similar body size. This result is in agreement with the longevity hypothesis, and contradicts the hypothesis of a metabolic rate-dependent mutation rate. Birds show no footprint of adaptive selection on cytochrome b evolutionary patterns, but no link between direct estimates of population size and cytochrome b diversity. The mutation rate is the best predictor we have of within-species mitochondrial diversity in birds. It partly explains the differences in mitochondrial DNA diversity patterns observed between mammals and birds, previously interpreted as reflecting Hill-Robertson interferences with the W chromosome. Mitochondrial DNA diversity patterns in

  8. The erratic mitochondrial clock: variations of mutation rate, not population size, affect mtDNA diversity across birds and mammals

    Directory of Open Access Journals (Sweden)

    Galtier Nicolas

    2009-03-01

    Full Text Available Abstract Background During the last ten years, major advances have been made in characterizing and understanding the evolution of mitochondrial DNA, the most popular marker of molecular biodiversity. Several important results were recently reported using mammals as model organisms, including (i the absence of relationship between mitochondrial DNA diversity and life-history or ecological variables, (ii the absence of prominent adaptive selection, contrary to what was found in invertebrates, and (iii the unexpectedly large variation in neutral substitution rate among lineages, revealing a possible link with species maximal longevity. We propose to challenge these results thanks to the bird/mammal comparison. Direct estimates of population size are available in birds, and this group presents striking life-history trait differences with mammals (higher mass-specific metabolic rate and longevity. These properties make birds the ideal model to directly test for population size effects, and to discriminate between competing hypotheses about the causes of substitution rate variation. Results A phylogenetic analysis of cytochrome b third-codon position confirms that the mitochondrial DNA mutation rate is quite variable in birds, passerines being the fastest evolving order. On average, mitochondrial DNA evolves slower in birds than in mammals of similar body size. This result is in agreement with the longevity hypothesis, and contradicts the hypothesis of a metabolic rate-dependent mutation rate. Birds show no footprint of adaptive selection on cytochrome b evolutionary patterns, but no link between direct estimates of population size and cytochrome b diversity. The mutation rate is the best predictor we have of within-species mitochondrial diversity in birds. It partly explains the differences in mitochondrial DNA diversity patterns observed between mammals and birds, previously interpreted as reflecting Hill-Robertson interferences with the W

  9. Academic outcomes in school classes with markedly disruptive pupils

    OpenAIRE

    Bru, Edvin

    2009-01-01

    The aim of the present research is to investigate the degree to which average academic outcomes in secondary school classes are associated with the inclusion of markedly disruptive pupils. Findings are based on two separate studies among pupils in Norwegian secondary schools. The first s tudy i ncluded a r elatively large sample of 2,332 pupils from 105 school classes and used pupil report of disruptive behaviour, perceived peace to learn and grades achieved. A second study, co...

  10. Pupil modeling of the legibility of class teachers’ board writing

    Directory of Open Access Journals (Sweden)

    Seyit Ateş

    2009-07-01

    Full Text Available The main aim of this study was to examine the pupil modeling of the legibility of class teachers’ writing on the classroom board. A stylistic quality of writing, legibility is evaluated by criteria such as letter slope, spacing, size, shape and line straightness. The study group included 70 class teachers from 13 primary schools at the city center of Kırşehir. The study was a descriptive situation analysis and data were gathered by the document analysis method. Writing samples were gathered by photographing classroom boards, and then analyzed and evaluated by using legibility criteria. The results showed that while the majority of teachers used cursive and many used manuscript, some teachers used the two types of writing together. Among those who wrote cursive handwriting, almost half had inadequate slope but moderately adequate spacing, size, shape and line straightness. It was also found that writing on a blackboard produced better legible writing than that on a white board.

  11. Pupils' Perspectives on the Lived Pedagogy of the Classroom

    Science.gov (United States)

    Niemi, Reetta; Kumpulainen, Kristiina; Lipponen, Lasse; Hilppö, Jaakko

    2015-01-01

    This paper is based on a pedagogical action research initiative that explores what constitutes the "lived pedagogy" of the classroom from the pupils' perspective. Photography and group interviews were utilised to allow pupils to express their perspectives. The results show that pupils considered situations meaningful when they were able…

  12. Pupils' Humour Directed at Teachers: Its Types and Functions

    Science.gov (United States)

    Šedová, Klára

    2013-01-01

    Based on an analysis of 137 texts written by pupils, this paper examines pupils' humour directed at teachers, its types and social functions. The collected data are divided into three categories that describe different modes of teachers as targets of pupils' humour. The first mode describes teachers as unintentionally comical, the second as duped…

  13. Some Comments on Inquiries on Schools and Pupil Control.

    Science.gov (United States)

    Willower, Donald J.

    This speech, by the co-author of a bibliography of studies of pupil control, reviews literature on that subject, differentiating between studies on Pupil Control Ideology (PCI) and Pupil Control Behavior (PCB), describing instances of their interrelationship, and weighing the various merits of PCI and PCB instruments. The author concludes that…

  14. Teacher Pupil Control Ideology--Behavior Congruence and Job Satisfaction.

    Science.gov (United States)

    Willower, Donald J.; Heckert, J. Wayne

    The hypothesis that teacher pupil control ideology-behavior congruence would be positively related to teacher job satisfaction was tested. The rationale for the hypothesis was that teachers whose beliefs and behaviors concerning pupil control were consistent would be likely to be contented with their work. Pupil control was seen as a central…

  15. Toward Definition and Measurement of Pupil Control Behavior.

    Science.gov (United States)

    Helsel, A. Ray; Willower, Donald J.

    An attempt is made to define and measure pupil control "behavior." In order to measure pupil control behavior, an instrument called the Pupil Control Behavior (PCB) Form was developed and tested. The 31 custodial and 34 humanistic items were randomized, and the initial version of the PCB Form was administered in 20 schools in Illinois…

  16. Pupils' Attitudes toward Chemistry in Two Types of Czech Schools

    Science.gov (United States)

    Kubiatko, Milan; Balatova, Kristyna; Fancovicova, Jana; Prokop, Pavol

    2017-01-01

    Chemistry is a school subject that is not viewed favorably among pupils. Before we can improve pupils' attitudes toward chemistry, it is important to find out the problem as to why the attitudes are relatively negative. The research was focused on Czech lower secondary and secondary grammar school pupils' attitudes to the subject of chemistry.…

  17. Assisting Pupils in Mathematics Achievement (The Common Core Standards)

    Science.gov (United States)

    Ediger, Marlow

    2011-01-01

    Mathematics teachers must expect reasonably high standards of achievement from pupils. Too frequently, pupils attain at a substandard level and more optimal achievement is necessary. Thus, pupils should have self esteem needs met in the school and classroom setting. Thus, learners feel that mathematics is worthwhile and effort must be put forth to…

  18. Pupil Welfare in Finnish Schools -- Communal or Falling Apart?

    Science.gov (United States)

    Koskela, Teija; Määttä, Kaarina; Uusiautti, Satu

    2013-01-01

    The need for pupil welfare has increased in schools as has the need to renew the traditional teacher's work. The purpose of this article is to find out how committed the teachers are to pupil welfare work and how the school organisation supports pupil welfare work structurally and practically. The original research was carried out in northern…

  19. Cyberbullying: Its Nature and Impact in Secondary School Pupils

    Science.gov (United States)

    Smith, Peter K.; Mahdavi, Jess; Carvalho, Manuel; Fisher, Sonja; Russell, Shanette; Tippett, Neil

    2008-01-01

    Background: Cyberbullying describes bullying using mobile phones and the internet. Most previous studies have focused on the prevalence of text message and email bullying. Methods: Two surveys with pupils aged 11-16 years: (1) 92 pupils from 14 schools, supplemented by focus groups; (2) 533 pupils from 5 schools, to assess the generalisability of…

  20. Cyberbullying: Its Nature and Impact in Secondary School Pupils

    Science.gov (United States)

    Smith, Peter K.; Mahdavi, Jess; Carvalho, Manuel; Fisher, Sonja; Russell, Shanette; Tippett, Neil

    2008-01-01

    Background: Cyberbullying describes bullying using mobile phones and the internet. Most previous studies have focused on the prevalence of text message and email bullying. Methods: Two surveys with pupils aged 11-16 years: (1) 92 pupils from 14 schools, supplemented by focus groups; (2) 533 pupils from 5 schools, to assess the generalisability of…

  1. On Pupils' Self-Confidence in Mathematics: Gender Comparisons

    Science.gov (United States)

    Nurmi, Anu; Hannula, Markku; Maijala, Hanna; Pehkonen, Erkki

    2003-01-01

    In this paper we will concentrate on pupils' self-confidence in mathematics, which belongs to pupils' mathematical beliefs in themselves, and beliefs on achievement in mathematics. Research described consists of a survey of more than 3000 fifth-graders and seventh-graders. Furthermore, 40 pupils participated in a qualitative follow-up study…

  2. MOTIVATION AND COMMUNICATIVE ATTITUDES AMONG JAPANESE EFL PUPILS

    Directory of Open Access Journals (Sweden)

    Rie Adachi

    2015-07-01

    Full Text Available This paper describes how gender and age affect Japanese pupils’ motivation for learning English and their attitudes to communication with people from different cultures. A new foreign language curriculum was introduced to Japanese elementary schools in 2011. Although each school can officially choose any foreign language in its own right, most elementary schools are now conducting English activity. However, as most homeroom teachers lack both experiences and qualifications for teaching English, this activity puts them under pressure. In addition, the number of foreign assistant language teachers (ALTs is not sufficient in most elementary schools. The writer surveyed fifth and sixth grade pupils’ motivation and their communicative attitudes in Japan during 2010, before the new course program, “foreign language activities,” began in 2011. The data were collected from three elementary schools in Japan via a questionnaire. The items on the questionnaire are related to motivational attitudes, orientations (reasons for studying a foreign language, communicative attitudes and some other variables relevant to learning foreign languages. The main focus of this study is to examine motivational and attitudinal variables among the pupils with regard to learning English, especially gender and age effects on these variables. The results show that girls generally have higher scores on motivation and communicative attitudes. Most previous studies have also shown that girls generally have a positive attitude toward learning a foreign language. This study argues that the reason behind this positive attitude toward learning English is due to their positive attitude toward communication in general. With regard to the age, there are a few differences between two school grades. As there is only one year difference in age between fifth and sixth grade pupils, the result is to be expected. The study suggests that Japanese elementary schools face a number of

  3. Water scarcity conditions affect peach fruit size and polyphenol contents more severely than other fruit quality traits.

    Science.gov (United States)

    Rahmati, Mitra; Vercambre, Gilles; Davarynejad, Gholamhossein; Bannayan, Mohammad; Azizi, Majid; Génard, Michel

    2015-03-30

    The literature abounds with the impacts of drought conditions on the concentration of non-structural compounds (NSC) in peach fruits without distinction as to the direct effect of drought on fruit metabolism and its indirect effect through dilution. Moreover, there is a need to investigate the sensitivity of the fruit composition to progressive water deficit in semi-arid conditions, as well as the origin of variations in fruit composition - not only in carbohydrates and organic acids, but also in secondary metabolites such as polyphenols. The increase in stress intensity resulted in smaller fruits and a reduction in yield. Drought increased fruit dry matter content, structural dry matter (SDM) content and firmness due to lower water import to fruits, although drought reduced fruit surface conductance and its transpiration. Drought significantly affected the concentrations of each NSC either through the decrease in dilution and/or modifications of their metabolism. The increase in hexoses and sorbitol concentrations of fruits grown under drought conditions resulted in an increase in the sweetness index but not near harvest. Malic acid concentration and content:SDM ratio increased as drought intensified, whereas those of citric and quinic acids decreased. Polyphenol concentration and content increased under severe drought. The increase in stress intensity strongly affected fruit mass. The concentration of total carbohydrates and organic acid at harvest increased mainly through a decrease in fruit dilution, whereas the concentrations of polyphenols were also strongly affected through an impact on their metabolism. © 2014 Society of Chemical Industry.

  4. Genetic Dissection of Morphometric Traits Reveals That Phytochrome B Affects Nucleus Size and Heterochromatin Organization in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Basten L. Snoek

    2017-08-01

    Full Text Available Microscopically visible chromatin is partitioned into two major components in Arabidopsis thaliana nuclei. On one hand, chromocenters are conspicuous foci of highly condensed “heterochromatic” domains that contain mostly repeated sequences. On the other hand, less condensed and gene-rich “euchromatin” emanates from these chromocenters. This differentiation, together with the dynamic nature of chromatin compaction in response to developmental and environmental stimuli, makes Arabidopsis a powerful system for studying chromatin organization and dynamics. Heterochromatin dynamics can be monitored by measuring the Heterochromatin Index, i.e., the proportion of nuclei displaying well-defined chromocenters, or the DNA fraction of chromocenters (relative heterochromatin fraction. Both measures are composite traits, thus their values represent the sum of effects of various underlying morphometric properties. We exploited genetic variation between natural occurring accessions to determine the genetic basis of individual nucleus and chromocenter morphometric parameters (area, perimeter, density, roundness, and heterogeneity that together determine chromatin compaction. Our novel reductionist genetic approach revealed quantitative trait loci (QTL for all measured traits. Genomic colocalization among QTL was limited, which suggests a complex genetic regulation of chromatin compaction. Yet genomic intervals of QTL for nucleus size (area and perimeter both overlap with a known QTL for heterochromatin compaction that is explained by natural polymorphism in the red/far-red light and temperature receptor Phytochrome B. Mutant analyses and genetic complementation assays show that Phytochrome B is a negative regulator of nucleus size, revealing that perception of climatic conditions by a Phytochrome-mediated hub is a major determinant for coordinating nucleus size and heterochromatin compaction.

  5. Elevated air humidity affects hydraulic traits and tree size but not biomass allocation in young silver birches (Betula pendula

    Directory of Open Access Journals (Sweden)

    Arne eSellin

    2015-10-01

    Full Text Available As changes in air temperature, precipitation, and air humidity are expected in the coming decades, studies on the impact of these environmental shifts on plant growth and functioning are of major importance. Greatly understudied aspects of climate change include consequences of increasing air humidity on forest ecosystems, predicted for high latitudes. The main objective of this study was to find a link between hydraulic acclimation and shifts in trees’ resource allocation in silver birch (Betula pendula Roth in response to elevated air relative humidity (RH. A second question was whether the changes in hydraulic architecture depend on tree size. Two years of application of increased RH decreased the biomass accumulation in birch saplings, but the biomass partitioning among aboveground parts (leaves, branches, and stems remained unaffected. Increased stem Huber values (xylem cross-sectional area to leaf area ratio observed in trees under elevated RH did not entail changes in the ratio of non-photosynthetic to photosynthetic tissues. The reduction of stem-wood density is attributable to diminished mechanical load imposed on the stem, since humidified trees had relatively shorter crowns. Growing under higher RH caused hydraulic conductance of the root system (KR to increase, while KR (expressed per unit leaf area decreased and leaf hydraulic conductance increased with tree size. Saplings of silver birch acclimate to increasing air humidity by adjusting plant morphology (live crown length, slenderness, specific leaf area, and fine-root traits and wood density rather than biomass distribution among aboveground organs. The treatment had a significant effect on several hydraulic properties of the trees, while the shifts were largely associated with changes in tree size but not in biomass allocation.

  6. Particle size distribution, concentration, and magnetic attraction affect transport of polymer-modified Fe(0) nanoparticles in sand columns.

    Science.gov (United States)

    Phenrat, Tanapon; Kim, Hye-Jin; Fagerlund, Fritjof; Illangasekare, Tissa; Tilton, Robert D; Lowry, Gregory V

    2009-07-01

    The effect of particle concentration, size distribution (polydispersity) and magnetic attractive forces (Fe(0) content) on agglomeration and transport of poly(styrene sulfonate) (PSS) modified NZVI was studied in water-saturated sand (d(p) = 300 microm) columns. Particle concentrations ranged from 0.03 to 6 g/L in 5 mM NaCl/5 mM NaHCO3 at a pore water velocity of 3.2 x 10(-4) m/s. Three NZVI dispersions with different intrinsic particle size distributions obtained from sequential sedimentation are compared. The influence of magnetic attraction (Fe(0) content) on NZVI agglomeration and deposition in porous media is assessed by comparing the deposition behavior of PSS-modified NZVI (magnetic) having different Fe(0) contents with PSS-modified hematite (nonmagnetic) with the same surface modifier. At low particle concentration (30 mg/L) all particles were mobile in sand columns regardless of size or magnetic attractive forces. At high concentration (1 to 6 g/L), deposition of the relatively monodisperse dispersion containing PSS-modified NZVI (hydrodynamic radius (R(H)) = 24 nm) with the lowest Fe(0) content (4 wt%) is low (attachment efficiency (alpha) = 2.5 x 10(-3)), insensitive to particle concentration, and similar to PSS-modified hematite. At 1 to 6 g/L, the attachment efficiency of polydisperse dispersions containing both primary particles and sintered aggregates (R(H) from 15 to 260 nm) of PSS-modified NZVI with a range of Fe(0) content (10-60%) is greater (alpha = 1.2 x 10(-2) to 7.2 x 10(-2) and is sensitive to particle size distribution. The greater attachment for larger, more polydisperse Fe(0) nanoparticles with higher Fe(0) content is a result of their agglomeration during transport in porous media because the magnetic attractive force between particles increases with the sixth power of particle/agglomerate radius. A filtration model that considers agglomeration in porous media and subsequent deposition explains the observed transport of polydisperse PSS

  7. Alterations in Seed Development Gene Expression Affect Size and Oil Content of Arabidopsis Seeds1[C][W][OPEN

    Science.gov (United States)

    Fatihi, Abdelhak; Zbierzak, Anna Maria; Dörmann, Peter

    2013-01-01

    Seed endosperm development in Arabidopsis (Arabidopsis thaliana) is under control of the polycomb group complex, which includes Fertilization Independent Endosperm (FIE). The polycomb group complex regulates downstream factors, e.g. Pheres1 (PHE1), by genomic imprinting. In heterozygous fie mutants, an endosperm develops in ovules carrying a maternal fie allele without fertilization, finally leading to abortion. Another endosperm development pathway depends on MINISEED3 (a WRKY10 transcription factor) and HAIKU2 (a leucine-rich repeat kinase). While the role of seed development genes in the embryo and endosperm establishment has been studied in detail, their impact on metabolism and oil accumulation remained unclear. Analysis of oil, protein, and sucrose accumulation in mutants and overexpression plants of the four seed development genes revealed that (1) seeds carrying a maternal fie allele accumulate low oil with an altered composition of triacylglycerol molecular species; (2) homozygous mutant seeds of phe1, mini3, and iku2, which are smaller, accumulate less oil and slightly less protein, and starch, which accumulates early during seed development, remains elevated in mutant seeds; (3) embryo-specific overexpression of FIE, PHE1, and MINI3 has no influence on seed size and weight, nor on oil, protein, or sucrose content; and (4) overexpression of IKU2 results in seeds with increased size and weight, and oil content of overexpressed IKU2 seeds is increased by 35%. Thus, IKU2 overexpression represents a novel strategy for the genetic manipulation of the oil content in seeds. PMID:24014578

  8. Addition of pectin and soy soluble polysaccharide affects the particle size distribution of casein suspensions prepared from acidified skim milk.

    Science.gov (United States)

    Liu, JinRu; Nakamura, Akihiro; Corredig, Milena

    2006-08-23

    Pectins are negatively charged polysaccharides employed as stabilizers in acidified milk dispersions, where caseins aggregate because of the low pH and serum separation needs to be prevented. The objective of this research was to study the effect of charge on the stabilizing functionality of the polysaccharide in acid milk drinks. Unstandardized pectins with various charges (as degree of esterification, DE) as well as soybean soluble polysaccharide (SSPS) were tested for their stabilizing behavior as a function of pH and concentration. Skim milk was acidified by glucono-delta-lactone and then homogenized in the presence of polysaccharide at different pH values (in the range from 4.2 to 3.0). Measurements of particle size distribution demonstrated that pectins with a DE of 71.4, 68.6, and 67.4 stabilized milk at pH > 4.0. Pectins with a lower DE (63.9%) needed a higher concentration (0.4%) at the same pH to show a monomodal distribution of particle sizes. Pectins with lower DE (milk, at pH milk dispersion was pH-dependent, and results were similar to those for samples containing pectin alone. This suggested that in the mixture, pectin dominated the behavior over SSPS, even when an excess of SSPS was added to the dispersions before homogenization.

  9. Youtube? SFBTube! - Through pupils to the people

    Science.gov (United States)

    Wilms, Mareike; Dengg, Joachim

    2010-05-01

    Humankind is strongly affected by natural hazards: Earthquakes and volcanoes shake the solid earth, storms and floods happen more and more frequently due to climate change, tsunamis threaten coastal areas. As the human population continues to expand, and stresses on the environment multiply, the need for an understanding of the fundamental issues becomes more urgent. A major task of Collaborative Research Centre "Climate - Biogeochemistry Interactions in the Tropical Ocean" and Collaborative Research Centre "Volatiles and Fluids in Subduction Zones" is to explain how the different components of the earth system interact and how they affect the world's population. Both Collaborative Research Centres implement a joint outreach program to communicate their research activities and results to the general public. In doing so, new strategies in public outreach are essential - considering the fast pace of changes in communication media and the increasing importance of edutainment as a way to reach the public and particularly the younger generations. Outreach materials have to be interesting, easy to understand and fun to explore, but without sacrificing the scientific content. Therefore, videos for the internet (e. g. Youtube) are one promising way to reach that target group. Blogs, podcasts, wikis or being part of social networks such as Facebook are further ways. But "being present where young people are" is not enough. You have to speak their language, too. To take another step forward we hence involve a critical part of the target audience actively into this new communication strategy. School students are able to contribute innovative views and their own language in presenting science to the public. In cooperation with pupils and teachers, we experiment with those new approaches to public outreach. Wherever it is possible, we are also making use of international cooperations of both Collaborative Research Centres with partner institutions in Latin America and Western

  10. Safety and efficacy of phacoemulsification and intraocular lens implantation through a small pupil using minimal iris manipulation

    Directory of Open Access Journals (Sweden)

    Papaconstantinou D

    2016-05-01

    Full Text Available Dimitris Papaconstantinou, George Kalantzis, Dimitris Brouzas, Anastasios Kontaxakis, Chryssanthi Koutsandrea, Andreas Diagourtas, Ilias Georgalas Department of Ophthalmology, National and Kapodistrian University of Athens, Athens, Greece Purpose: The aim of this study was to compare the results of phacoemulsification through a small pupil using minimal iris manipulation versus phacoemulsification through a well-dilated pupil.Methods: This prospective randomized control (comparative study comprised 78 patients (group I with a maximally dilated pupil size of ≤4.00 mm and 45 patients (group II with dilated pupil size of ≥7.00 mm. In group I patients, only viscodilation and minimal push-and-pull iris stretching with two collar-button iris-retractor hooks were utilized without iris manipulation. Phacoemulsification was performed by two senior surgeons and the technique used consisted of either stop and chop or quick chop, infusion/aspiration of lens cortex, capsular bag refill with ocular viscoelastic devices, and implantation of an acrylic foldable intraocular lens. Patients were examined on the first day and 1 month postoperatively.Results: Forty-six eyes of group I patients had pseudoexfoliation syndrome, eleven eyes had previous glaucoma surgery, 14 eyes had angle-closure or open-angle glaucoma, and seven eyes had posterior synechiae with iritis. In group I patients, the mean pupil size measured under an operating microscope was 3.2 mm preoperatively, 4.3 mm after viscoelastic and mechanical pupil dilation, and 4.1 mm at the end of a surgical procedure. Rupture of the zonular fibers occurred in six patients of group I and the intraocular lens was implanted in the sulcus. Small iris-sphincter rupture and small hemorrhages occurred in four eyes during pupillary manipulation, but they were not evident at the end of the surgery. In group II patients, no intraoperative complications occurred. Signs of significant corneal edema and iritis

  11. Pupil phase discontinuity measurement: comparison of different wavefront sensing concepts

    Science.gov (United States)

    El Hadi, K.; Sauvage, J.-F.; Dohlen, K.; Fusco, T.; Neichel, B.; Marchis, F.; N'Diaye, M.

    2016-07-01

    The Laboratoire d'Astrophysique de Marseille is involved in the preparation of the E-ELT instrumentation framework: In particular, an ESO-EELT M1 mirror segment (1.5 m) has been demonstrated and different wavefront sensing (WFS) concepts among which Pyramid, Zernike phase mask sensor (ZELDA), Phase diversity or still NL Curvature) are also investigated. Segmented mirrors are widely used today in diverse domains: fiber coupling, laser beam shaping, microscopy or retina imaging. If, these mirrors offer a solution to realize important monolithic sizes for giant telescopes in astronomy, they also raise the problem of segments cophasing and measurement of phase discontinuities. In this work, we aim to investigate a suitable WFS approach for pupil phase discontinuity measurement. Coupling a segmented PTT mirror (Iris AO) with four different WFS (Shack-Hartmann, Quadriwave Lateral Shearing Interferometer, Pyramid and Zernike Phase Mask), we study their sensitivity to segmented pupil: in particular, segment phasing, stability, saturation, flat, or still the addressing mode are then performed and compared.

  12. Objective lens simultaneously optimized for pupil ghosting, wavefront delivery and pupil imaging

    Science.gov (United States)

    Olczak, Eugene G (Inventor)

    2011-01-01

    An objective lens includes multiple optical elements disposed between a first end and a second end, each optical element oriented along an optical axis. Each optical surface of the multiple optical elements provides an angle of incidence to a marginal ray that is above a minimum threshold angle. This threshold angle minimizes pupil ghosts that may enter an interferometer. The objective lens also optimizes wavefront delivery and pupil imaging onto an optical surface under test.

  13. Objective Lens Optimized for Wavefront Delivery, Pupil Imaging, and Pupil Ghosting

    Science.gov (United States)

    Olzcak, Gene

    2009-01-01

    An interferometer objective lens (or diverger) may be used to transform a collimated beam into a diverging or converging beam. This innovation provides an objective lens that has diffraction-limited optical performance that is optimized at two sets of conjugates: imaging to the objective focus and imaging to the pupil. The lens thus provides for simultaneous delivery of a high-quality beam and excellent pupil resolution properties.

  14. Diagnostics of Pupils' Attitude to Education

    Science.gov (United States)

    Eminli, Tovuz

    2011-01-01

    The paper is devoted to the investigation of the questions connected with the pedagogical diagnostics, in particular, the diagnostics of pupils' attitude to education. It is considered reasonable to apply the practice of development of an individual pedagogical and psychological map for productive implementation of the pedagogical diagnostics and…

  15. Psychometric aspects of pupil monitoring systems

    NARCIS (Netherlands)

    Glas, Cees A.W.; Geerlings, Hanneke

    2009-01-01

    Pupil monitoring systems support the teacher in tailoring teaching to the individual level of a student and in comparing the progress and results of teaching with national standards. The systems are based on the availability of an item bank calibrated using item response theory. The assessment of th

  16. Experimental Economics method to study pupils motivation

    OpenAIRE

    Lionel Page

    2010-01-01

    Experimental Economics provide a new set of tools in the tool box of the education economist. This paper review why experimental method may be useful to study how pupils behaviour, formed from their preference and beliefs, may influence their success or failure at school, what are its advantages and what are its limits. Behavioural Economics - Education - Public Policy

  17. North Yorkshire Schools' Responses to Pupil Bereavement

    Science.gov (United States)

    Holland, John; McLennan, Derek

    2015-01-01

    This was a research project carried out in North Yorkshire schools by the loss and bereavement research group of the Educational Psychology Service. The background was an interest in how schools responded to bereaved pupils, whether they had a structured response, trained staff and training needs, from where they sought support and the level of…

  18. Curricular Content for Pupils' Mental Health

    Science.gov (United States)

    Ebadi, Seyed Hossein; Keshtiaray, Narges; Aghaei, Asghar; Yousefy, Alireza

    2016-01-01

    Present-day curricular designs have to take the pupils' psychological needs in account, thus becoming melodies of mental health and happiness for the next generation. Emphasizing the findings from previous investigations using the research synthesis methodology, the present study has been conducted aiming at achieving some integrative knowledge…

  19. Manual for School Administrators on Pupil Transportation.

    Science.gov (United States)

    Tennessee State Dept. of Education, Nashville.

    Guiding principles, state laws, and state board rules and regulations are covered, providing school administrators with a ready reference in the field of pupil transportation. Divided into three sections, the manual initially covers administrative procedures including--(1) the purchase of buses, (2) bus maintenance, (3) employment of drivers, (4)…

  20. Motivating Pupils To Learn in Mathematics.

    Science.gov (United States)

    Ediger, Marlow

    The mathematics teacher has a major responsibility in assisting pupils to learn in ongoing lessons and units of study. This paper discusses ways of motivating students in the mathematics classroom from the perspectives of different learning theories such as behaviorism, humanism, cognitive psychology, and constructivism. Guidelines for teaching…

  1. Shared Reading, the Pupil, and the Teacher

    Science.gov (United States)

    Ediger, Marlow

    2011-01-01

    Pupil/teacher interaction provides opportunities for many kinds of learning experiences. Within the reading curriculum, there are a plethora of activities in oral communication and working together harmoniously. Thus from every day experiences, the teacher may communicate verbally what he/she has read in an interesting, informative manner on the…

  2. Empowering Primary School Pupils through Literacy Remediation ...

    African Journals Online (AJOL)

    FIRST LADY

    often fail to engage the pupils in activities that promote literacy development. The result .... literacy skills for effective learning, the researchers used the vacation reading .... Print Referencing involves both verbal and non-verbal cues used to draw ... a shiny red bucket that performs many functions but on getting old and tired.

  3. Secondary school pupils' food choices around schools in a London borough: Fast food and walls of crisps.

    Science.gov (United States)

    Caraher, M; Lloyd, S; Mansfield, M; Alp, C; Brewster, Z; Gresham, J

    2016-08-01

    The objective was to observe and document food behaviours of secondary school pupils from schools in a London borough. The research design combined a number of methods which included geographic information system (GIS) mapping of food outlets around three schools, systemised observations of food purchasing in those outlets before, during and after school, and focus groups conducted with pupils of those schools to gather their views in respect to those food choices. Results are summarised under the five 'A's of Access, Availability, Affordability and Acceptability & Attitudes: Access in that there were concentrations of food outlets around the schools. The majority of pupil food purchases were from newsagents, small local shops and supermarkets of chocolate, crisps (potato chips), fizzy drinks and energy drinks. Availability of fast food and unhealthy options were a feature of the streets surrounding the schools, with 200 m the optimal distance pupils were prepared to walk from and back to school at lunchtime. Affordability was ensured by the use of a consumer mentality and pupils sought out value for money offers; group purchasing of 'two for one' type offers encouraged this trend. Pupils reported healthy items on sale in school as expensive, and also that food was often sold in smaller portion sizes than that available from external food outlets. Acceptability and Attitudes, in that school food was not seen as 'cool', queuing for school food was not acceptable but queuing for food from takeaways was not viewed negatively; for younger pupils energy drinks were 'cool'. In conclusion, pupils recognised that school food was healthier but provided several reasons for not eating in school related to the five 'A's above.

  4. Pupil movements to light and accommodative stimulation - A comparative study.

    Science.gov (United States)

    Semmlow, J.; Stark, L.

    1973-01-01

    Isolation and definition of specific response components in pupil reflexes through comparison of the dynamic features of light-induced and accommodation-induced pupil movements. A quantitative analysis of the behavior of the complex nonlinear pupil responses reveals the presence of two independent nonlinear characteristics: a range-dependent gain and a direction dependence or movement asymmetry. These nonlinear properties are attributed to motor processes because they are observable in pupil responses to both light and accommodation stimuli. The possible mechanisms and consequences of these pupil response characteristics are quantitatively defined and discussed.

  5. Do normal pupil diameter differences in the population underlie the color selection of #thedress?

    Science.gov (United States)

    Vemuri, Kavita; Bisla, Kulvinder; Mulpuru, SaiKrishna; Varadharajan, Srinivasa

    2016-03-01

    The fundamental question that arises from the color conundrum of #thedress is "What are the phenomena that underlie the individual differences in the reported colors when all other conditions like light and device for the display are identical?" A survey of 384 participants showed near-equal distribution into blue/black (b/b) and white/gold (w/g) groups. We looked at pupil size differences in a sample population of 53 individuals from these two groups and a group that switched from w/g to b/b. Our results showed that the w/g and switch groups had significantly lower pupil size than the b/b group (w/gpupil size. A standard infinity focus experiment was then conducted on 18 participants from each group to check if there is bimodality in the population, and we found a statistically significant difference (w/gpupil size by 3-4 mm, but the participants did not report a switch. The results suggest a population difference in normal pupil size influencing color observation which was exposed by the dress.

  6. Lake size and water-column stability affect the importance of methane for pelagic food webs of boreal lakes

    Science.gov (United States)

    Kankaala, Paula; Lopez-Bellido, Jessica; Ojala, Anne; Tulonen, Tiina; Jones, Roger I.

    2013-04-01

    Physical forcing, related to lake size and morphometry, plays an important role in the landscape-scale biogeochemical processing and fluxes of terrestrial carbon in lakes. Boreal lakes are typically dimictic, with mixing of the water column in spring and autumn, but in small, sheltered, humic, forest lakes the spring mixing is often incomplete. This leads to a steep summer stratification and oxygen depletion in the hypolimnion of the lakes. As a result of anaerobic decomposition of organic matter, high concentrations of CH4are typical in these lakes. At the oxic-anoxic interface zone methanotrophic microbes oxidize CH4 to CO2 and partly incorporate CH4-C into microbial biomass, and thus potentially provide a diet source for pelagic consumers. We studied production at the base of the pelagic food web by methane oxidising bacteria (MOB), heterotrophic bacteria (HB) and phytoplankton (PP) in five boreal lakes with a dissolved organic carbon (DOC) concentration varying between 7 and 25 mg C L-1 and an area ranging from 0.004 to 13.4 km2. High MOB activity was detected in the water columns of the three smallest lakes having anoxia in the hypolimnion during summer. The highest MOB activities (ca. 2-12 μmol L-1 d-1) were observed when the CH4:O2 ratio varied between ca. 0.5-12. Seasonally, the highest MOB activities were measured during late-summer mixed layer deepening and autumnal mixing of the whole water column. The proportion of MOB in the total basal production was highest in the two smallest lakes (24-56 and 13-36%), having the steepest summertime stratification. The proportion MOB in the basal production decreased with lake size being 70% of basal production was by PP. In all studied lakes HB contributed only 10-23% of the total basal production, suggesting that a transfer of allochthonous DOC via HB plays only a modest role for the nutrition of the higher trophic levels.

  7. Pupil Alignment Considerations for Large, Deployable Space Telescopes

    Science.gov (United States)

    Bos, Brent J.; Ohl, Raymond G.; Kubalak, Daivd A.

    2011-01-01

    For many optical systems the properties and alignment of the internal apertures and pupils are not critical or controlled with high precision during optical system design, fabrication or assembly. In wide angle imaging systems, for instance, the entrance pupil position and orientation is typically unconstrained and varies over the system s field of view in order to optimize image quality. Aperture tolerances usually do not receive the same amount of scrutiny as optical surface aberrations or throughput characteristics because performance degradation is typically graceful with misalignment, generally only causing a slight reduction in system sensitivity due to vignetting. But for a large deployable space-based observatory like the James Webb Space Telescope (JWST), we have found that pupil alignment is a key parameter. For in addition to vignetting, JWST pupil errors cause uncertainty in the wavefront sensing process that is used to construct the observatory on-orbit. Furthermore they also open stray light paths that degrade the science return from some of the telescope s instrument channels. In response to these consequences, we have developed several pupil measurement techniques for the cryogenic vacuum test where JWST science instrument pupil alignment is verified. These approaches use pupil alignment references within the JWST science instruments; pupil imaging lenses in three science instrument channels; and unique pupil characterization features in the optical test equipment. This will allow us to verify and crosscheck the lateral pupil alignment of the JWST science instruments to approximately 1-2% of their pupil diameters.

  8. Biases in grant proposal success rates, funding rates and award sizes affect the geographical distribution of funding for biomedical research.

    Science.gov (United States)

    Wahls, Wayne P

    2016-01-01

    The ability of the United States to most efficiently make breakthroughs on the biology, diagnosis and treatment of human diseases requires that physicians and scientists in each state have equal access to federal research grants and grant dollars. However, despite legislative and administrative efforts to ensure equal access, the majority of funding for biomedical research is concentrated in a minority of states. To gain insight into the causes of such disparity, funding metrics were examined for all NIH research project grants (RPGs) from 2004 to 2013. State-by-state differences in per application success rates, per investigator funding rates, and average award size each contributed significantly to vast disparities (greater than 100-fold range) in per capita RPG funding to individual states. To the extent tested, there was no significant association overall between scientific productivity and per capita funding, suggesting that the unbalanced allocation of funding is unrelated to the quality of scientists in each state. These findings reveal key sources of bias in, and new insight into the accuracy of, the funding process. They also support evidence-based recommendations for how the NIH could better utilize the scientific talent and capacity that is present throughout the United States.

  9. Seed Size, the Only Factor Positively Affecting Direct Seeding Success in an Abandoned Field in Quebec, Canada

    Directory of Open Access Journals (Sweden)

    Annick St-Denis

    2013-06-01

    Full Text Available Direct tree seeding is potentially an economical technique for restoring forests on abandoned fields. However, the success of tree establishment depends on many factors related to species and seed characteristics, environmental conditions, competition and predation. We compared seedling emergence, survival and growth of six tree species of different seed sizes in a forest restoration project of abandoned fields. Species were seeded in plots with and without herbaceous vegetation and with and without protection from bird and mammal predation. Yellow birch (Betula alleghaniensis did not emerge in all treatments, paper birch (Betula papyrifera and tamarack (Larix laricina had a seedling emergence rate lower than 1%, and sugar maple (Acer saccharum had a low overall emergence rate of 6%. Seedling emergence reached 57% for northern red oak (Quercus rubra and 34% for red pine (Pinus resinosa, but survival of oak after one year was much higher (92% than pine seedlings (16%. Overall, protection from birds and mammals and elimination of the herbaceous vegetation cover had no detectable effects on seedling emergence, survival and height. Nonetheless, red oak seedlings growing in the presence of vegetation had a smaller diameter and shoot biomass and a larger specific leaf area. We conclude that only large seeded species, such as oak, should be used for forest restoration of abandoned fields by direct seeding in our region.

  10. Plane of nutrition affects growth rate, organ size and skeletal muscle satellite cell activity in newborn calves.

    Science.gov (United States)

    MacGhee, M E; Bradley, J S; McCoski, S R; Reeg, A M; Ealy, A D; Johnson, S E

    2016-11-18

    Plane of nutrition effects on body, tissue and cellular growth in the neonatal calf are poorly understood. The hypothesis that a low plane of nutrition (LPN) would limit skeletal muscle size by reducing fibre growth and muscle progenitor cell activity was tested. At birth, calves were randomly assigned to either a LPN (20% CP, 20% fat; GE=1.9 Mcal/days) or a high plane of nutrition (HPN; 27% CP, 10% fat, GE = 3.8 Mcal/days) in a 2 × 3 factorial design to test the impact of diet on neonatal calf growth, organ weight and skeletal muscle morphometry with time. Groups of calves (n = 4 or 5) were euthanised at 2, 4 and 8 week of age and organ and empty carcass weights were recorded. Body composition was measured by DXA. Longissimus muscle (LM) fibre cross-sectional area (CSA), fibre/mm(2) and Pax7 were measured by immunohistology. Satellite cells were isolated at each time point and proliferation rates were measured by EdU incorporation. Calves fed a HPN had greater (p satellite cells per fibre. Proliferation rates of satellite cells isolated from HPN fed calves were greater (p satellite cell activity.

  11. How Do the Size, Charge and Shape of Nanoparticles Affect Amyloid β Aggregation on Brain Lipid Bilayer?

    Science.gov (United States)

    Kim, Yuna; Park, Ji-Hyun; Lee, Hyojin; Nam, Jwa-Min

    2016-01-19

    Here, we studied the effect of the size, shape, and surface charge of Au nanoparticles (AuNPs) on amyloid beta (Aβ) aggregation on a total brain lipid-based supported lipid bilayer (brain SLB), a fluid platform that facilitates Aβ-AuNP aggregation process. We found that larger AuNPs induce large and amorphous aggregates on the brain SLB, whereas smaller AuNPs induce protofibrillar Aβ structures. Positively charged AuNPs were more strongly attracted to Aβ than negatively charged AuNPs, and the stronger interactions between AuNPs and Aβ resulted in fewer β-sheets and more random coil structures. We also compared spherical AuNPs, gold nanorods (AuNRs), and gold nanocubes (AuNCs) to study the effect of nanoparticle shape on Aβ aggregation on the brain SLB. Aβ was preferentially bound to the long axis of AuNRs and fewer fibrils were formed whereas all the facets of AuNCs interacted with Aβ to produce the fibril networks. Finally, it was revealed that different nanostructures induce different cytotoxicity on neuroblastoma cells, and, overall, smaller Aβ aggregates induce higher cytotoxicity. The results offer insight into the roles of NPs and brain SLB in Aβ aggregation on the cell membrane and can facilitate the understanding of Aβ-nanostructure co-aggregation mechanism and tuning Aβ aggregate structures.

  12. Biases in grant proposal success rates, funding rates and award sizes affect the geographical distribution of funding for biomedical research

    Directory of Open Access Journals (Sweden)

    Wayne P. Wahls

    2016-04-01

    Full Text Available The ability of the United States to most efficiently make breakthroughs on the biology, diagnosis and treatment of human diseases requires that physicians and scientists in each state have equal access to federal research grants and grant dollars. However, despite legislative and administrative efforts to ensure equal access, the majority of funding for biomedical research is concentrated in a minority of states. To gain insight into the causes of such disparity, funding metrics were examined for all NIH research project grants (RPGs from 2004 to 2013. State-by-state differences in per application success rates, per investigator funding rates, and average award size each contributed significantly to vast disparities (greater than 100-fold range in per capita RPG funding to individual states. To the extent tested, there was no significant association overall between scientific productivity and per capita funding, suggesting that the unbalanced allocation of funding is unrelated to the quality of scientists in each state. These findings reveal key sources of bias in, and new insight into the accuracy of, the funding process. They also support evidence-based recommendations for how the NIH could better utilize the scientific talent and capacity that is present throughout the United States.

  13. Genetic deletion of Rab27B in pancreatic acinar cells affects granules size and has inhibitory effects on amylase secretion.

    Science.gov (United States)

    Hou, Yanan; Ernst, Stephen A; Lentz, Stephen I; Williams, John A

    2016-03-18

    Small G protein Rab27B is expressed in various secretory cell types and plays a role in mediating secretion. In pancreatic acinar cells, Rab27B was found to be expressed on the zymogen granule membrane and by overexpression to regulate the secretion of zymogen granules. However, the effect of Rab27B deletion on the physiology of pancreatic acinar cells is unknown. In the current study, we utilized the Rab27B KO mouse model to better understand the role of Rab27B in the secretion of pancreatic acinar cells. Our data show that Rab27B deficiency had no obvious effects on the expression of major digestive enzymes and other closely related proteins, e.g. similar small G proteins, such as Rab3D and Rab27A, and putative downstream effectors. The overall morphology of acinar cells was not changed in the knockout pancreas. However, the size of zymogen granules was decreased in KO acinar cells, suggesting a role of Rab27B in regulating the maturation of secretory granules. The secretion of digestive enzymes was moderately decreased in KO acini, compared with the WT control. These data indicate that Rab27B is involved at a different steps of zymogen granule maturation and secretion, which is distinct from that of Rab3D.

  14. Infant milk fat droplet size and coating affect postprandial responses in healthy adult men: a proof-of-concept study.

    Science.gov (United States)

    Baumgartner, S; van de Heijning, B J M; Acton, D; Mensink, R P

    2017-09-01

    Fat droplets in human milk (HM) are larger and surrounded by a phospholipid membrane compared with infant milk formulas (IMF). Since the physical structure of fat droplets might affect digestion and postprandial metabolism, an IMF was developed more mimicking HM lipid structure than current IMF. A randomised, double-blind, crossover study was performed in 29 fasted healthy men (aged 18-25 years, BMI: 18-25 kg/m(2)) to compare 5-hour postprandial responses after consumption of an experimental IMF (Concept, Nuturis) with a current IMF (Control). Postprandial triacylglycerol (TAG) concentrations tended to increase faster after intake of Concept IMF (P=0.054), but peaked 3 h after intakes at similar concentrations. ApoB48 increased steadily and peaked 3 h after consumption. Increases in plasma glucose concentrations were comparable, but peak concentrations were reached faster after consumption of Concept IMF (PIMF, causing a sharper decremental glucose rebound (PIMF. Satiety scores and changes in the satiety hormones ghrelin and peptide YY were comparable, while cholecystokinin responses were earlier and higher after consumption of Control IMF (PIMF with larger and phospholipid-coated fat droplets are more rapidly absorbed than those from the current IMF.

  15. Genetic Ablation of Soluble TNF Does Not Affect Lesion Size and Functional Recovery after Moderate Spinal Cord Injury in Mice

    Directory of Open Access Journals (Sweden)

    Ditte Gry Ellman

    2016-01-01

    Full Text Available Traumatic spinal cord injury (SCI is followed by an instant increase in expression of the microglial-derived proinflammatory cytokine tumor necrosis factor (TNF within the lesioned cord. TNF exists both as membrane-anchored TNF (mTNF and as cleaved soluble TNF (solTNF. We previously demonstrated that epidural administration of a dominant-negative inhibitor of solTNF, XPro1595, to the contused spinal cord resulted in changes in Iba1 protein expression in microglia/macrophages, decreased lesion volume, and improved locomotor function. Here, we extend our studies using mice expressing mTNF, but no solTNF (mTNFΔ/Δ, to study the effect of genetic ablation of solTNF on SCI. We demonstrate that TNF levels were significantly decreased within the lesioned spinal cord 3 days after SCI in mTNFΔ/Δ mice compared to littermates. This decrease did, however, not translate into significant changes in other pro- and anti-inflammatory cytokines (IL-10, IL-1β, IL-6, IL-5, IL-2, CXCL1, CCL2, or CCL5, despite a tendency towards increased IL-10 and decreased IL-1β, TNFR1, and TNFR2 levels in mTNFΔ/Δ mice. In addition, microglial and leukocyte infiltration, activation state (Iba1, CD11b, CD11c, CD45, and MHCII, lesion size, and functional outcome after moderate SCI were comparable between genotypes. Collectively, our data demonstrate that genetic ablation of solTNF does not significantly modulate postlesion outcome after SCI.

  16. Spider Movement, UV Reflectance and Size, but Not Spider Crypsis, Affect the Response of Honeybees to Australian Crab Spiders

    Science.gov (United States)

    Llandres, Ana L.; Rodríguez-Gironés, Miguel A.

    2011-01-01

    According to the crypsis hypothesis, the ability of female crab spiders to change body colour and match the colour of flowers has been selected because flower visitors are less likely to detect spiders that match the colour of the flowers used as hunting platform. However, recent findings suggest that spider crypsis plays a minor role in predator detection and some studies even showed that pollinators can become attracted to flowers harbouring Australian crab spider when the UV contrast between spider and flower increases. Here we studied the response of Apis mellifera honeybees to the presence of white or yellow Thomisus spectabilis Australian crab spiders sitting on Bidens alba inflorescences and also the response of honeybees to crab spiders that we made easily detectable painting blue their forelimbs or abdomen. To account for the visual systems of crab spider's prey, we measured the reflectance properties of the spiders and inflorescences used for the experiments. We found that honeybees did not respond to the degree of matching between spiders and inflorescences (either chromatic or achromatic contrast): they responded similarly to white and yellow spiders, to control and painted spiders. However spider UV reflection, spider size and spider movement determined honeybee behaviour: the probability that honeybees landed on spider-harbouring inflorescences was greatest when the spiders were large and had high UV reflectance or when spiders were small and reflected little UV, and honeybees were more likely to reject inflorescences if spiders moved as the bee approached the inflorescence. Our study suggests that only the large, but not the small Australian crab spiders deceive their preys by reflecting UV light, and highlights the importance of other cues that elicited an anti-predator response in honeybees. PMID:21359183

  17. Neuronal activity in primate dorsal anterior cingulate cortex signals task conflict and predicts adjustments in pupil-linked arousal.

    Science.gov (United States)

    Ebitz, R Becket; Platt, Michael L

    2015-02-04

    Whether driving a car, shopping for food, or paying attention in a classroom of boisterous teenagers, it's often hard to maintain focus on goals in the face of distraction. Brain imaging studies in humans implicate the dorsal anterior cingulate cortex (dACC) in regulating the conflict between goals and distractors. Here we show that single dACC neurons signal conflict between task goals and distractors in the rhesus macaque, particularly for biologically relevant social stimuli. For some neurons, task conflict signals predicted subsequent changes in pupil size-a peripheral index of arousal linked to noradrenergic tone-associated with reduced distractor interference. dACC neurons also responded to errors, and these signals predicted adjustments in pupil size. These findings provide the first neurophysiological endorsement of the hypothesis that dACC regulates conflict, in part, via modulation of pupil-linked processes such as arousal. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Test-retest repeatability of the pupil light response to blue and red light stimuli in normal human eyes using a novel pupillometer

    DEFF Research Database (Denmark)

    Herbst, Kristina; Sander, Birgit; Milea, Dan;

    2011-01-01

    In this study, we evaluated the repeatability of pupil responses to colored light stimuli in healthy subjects using a prototype chromatic pupillometer. One eye of 10 healthy subjects was tested twice in the same day using monochromatic light exposure at two selected wavelengths (660 and 470 nm...... stimulation as the total area between a reference line representing baseline pupil size and the line representing actual pupil size over 20 s (area under the curve). There was no significant difference in the repeated measure compared to the first test for any of the pupil response parameters. In conclusion......, we have developed a novel prototype of color pupillometer which demonstrates good repeatability in evoking and recording the pupillary response to a bright blue and red light stimulus....

  19. Ethnic boundaries and personal choice. Assessing the influence of individual inclinations to choose intra-ethnic relationships on pupils' networks : Assessing the influence of individual inclinations to choose intra-ethnic relationships on pupils’ networks

    NARCIS (Netherlands)

    Baerveldt, C; Van Duijn, MAJ; Vermeij, L; Van Hemert, DA; Hemert, Dianne A. van

    2004-01-01

    The existence of ethnic boundaries in 20 pupils' networks is tested by comparing the proportion of intra-ethnic to inter-ethnic relationships, while controlling for the distribution of intra- and inter-ethnic dyads in pupils' networks. Also, we tested if those boundaries are affected by the inclinat

  20. Did the late spring frost in 2007 and 2011 affect tree-ring width and earlywood vessel size in Pedunculate oak ( Quercus robur) in northern Poland?

    Science.gov (United States)

    Puchałka, Radosław; Koprowski, Marcin; Przybylak, Julia; Przybylak, Rajmund; Dąbrowski, Henryk P.

    2016-08-01

    Trees are sensitive to extreme weather and environmental conditions. This sensitivity is visible in tree-ring widths and cell structure. In our study, we hypothesized that the sudden frost noted at the beginning of May in both 2007 and 2011 affected cambial activity and, consequently, the number and size of vessels in the tree rings. It was decided to test this hypothesis after damage to leaves was observed. The applied response function model did not show any significant relationships between spring temperature and growth. However, this method uses average values for long periods and sometimes misses the short-term effects. This is why we decided to study each ring separately, comparing them with rings unaffected by the late frost. Our study showed that the short-term effect of sudden frost in late spring did not affect tree rings and selected cell parameters. The most likely reasons for this are (i) cambial activity producing the earlywood vessels before the occurrence of the observed leaf damage, (ii) the forest micro-climate protecting the trees from the harsh frost and (iii) the temperature decline being too short-lived an event to affect the oaks. On the other hand, the visible damage may be occasional and not affect cambium activity and tree vitality at all. We conclude that oak is well-adapted to this phenomenon.

  1. Safety and efficacy of phacoemulsification and intraocular lens implantation through a small pupil using minimal iris manipulation

    Science.gov (United States)

    Papaconstantinou, Dimitris; Kalantzis, George; Brouzas, Dimitris; Kontaxakis, Anastasios; Koutsandrea, Chryssanthi; Diagourtas, Andreas; Georgalas, Ilias

    2016-01-01

    Purpose The aim of this study was to compare the results of phacoemulsification through a small pupil using minimal iris manipulation versus phacoemulsification through a well-dilated pupil. Methods This prospective randomized control (comparative) study comprised 78 patients (group I) with a maximally dilated pupil size of ≤4.00 mm and 45 patients (group II) with dilated pupil size of ≥7.00 mm. In group I patients, only viscodilation and minimal push-and-pull iris stretching with two collar-button iris-retractor hooks were utilized without iris manipulation. Phacoemulsification was performed by two senior surgeons and the technique used consisted of either stop and chop or quick chop, infusion/aspiration of lens cortex, capsular bag refill with ocular viscoelastic devices, and implantation of an acrylic foldable intraocular lens. Patients were examined on the first day and 1 month postoperatively. Results Forty-six eyes of group I patients had pseudoexfoliation syndrome, eleven eyes had previous glaucoma surgery, 14 eyes had angle-closure or open-angle glaucoma, and seven eyes had posterior synechiae with iritis. In group I patients, the mean pupil size measured under an operating microscope was 3.2 mm preoperatively, 4.3 mm after viscoelastic and mechanical pupil dilation, and 4.1 mm at the end of a surgical procedure. Rupture of the zonular fibers occurred in six patients of group I and the intraocular lens was implanted in the sulcus. Small iris-sphincter rupture and small hemorrhages occurred in four eyes during pupillary manipulation, but they were not evident at the end of the surgery. In group II patients, no intraoperative complications occurred. Signs of significant corneal edema and iritis were observed more frequently in group I eyes (26 eyes and 20 eyes, respectively) on the first postoperative day in comparison with group II eyes (ten eyes and six eyes, respectively). Intraocular pressure was <20 mmHg in all eyes of both groups. One month

  2. Pupil cycle time and early autonomic involvement in ocular leprosy.

    Science.gov (United States)

    Karaçorlu, M A; Sürel, Z; Cakiner, T; Hanyaloğlu, E; Saylan, T; Mat, C

    1991-01-01

    Ocular complications of leprosy patients often develop insidiously and with few if any symptoms. This study involves measurement of the pupil cycle time (PCT) to evaluate the autonomic nerve system of the iris to determine the presence of subclinical intraocular involvement. The study included 19 lepromatous (LL), 19 borderline lepromatous (BL), and five borderline tuberculoid (BT) leprosy patients and involved 25 healthy volunteers, 10 patients with pulmonary tuberculosis and eight with Duhring disease. The PCT was measured in these groups. In all leprosy groups included in the study the PCT was higher than in the control groups. Moreover, the PCT of the leprosy patients without any intraocular involvement was higher than in the controls. These results show that in the ophthalmic examination of leprosy patients without any symptoms the fact that autonomic nerve system of the eye is affected by the leprosy can often be determined by measuring the PCT.

  3. The Asymmetric Pupil Fourier Wavefront Sensor

    CERN Document Server

    Martinache, Frantz

    2013-01-01

    This paper introduces a novel wavefront sensing approach that relies on the Fourier analysis of a single conventional direct image. In the high Strehl ratio regime, the relation between the phase measured in the Fourier plane and the wavefront errors in the pupil can be linearized, as was shown in a previous work that introduced the notion of generalized closure-phase, or kernel-phase. The technique, to be usable as presented requires two conditions to be met: (1) the wavefront errors must be kept small (of the order of one radian or less) and (2) the pupil must include some asymmetry, that can be introduced with a mask, for the problem to become solvable. Simulations show that this asymmetric pupil Fourier wavefront sensing or APF-WFS technique can improve the Strehl ratio from 50 to over 90 % in just a few iterations, with excellent photon noise sensitivity properties, suggesting that on-sky close loop APF-WFS is possible with an extreme adaptive optics system.

  4. The Size of Activating and Inhibitory Killer Ig-like Receptor Nanoclusters Is Controlled by the Transmembrane Sequence and Affects Signaling

    Directory of Open Access Journals (Sweden)

    Anna Oszmiana

    2016-05-01

    Full Text Available Super-resolution microscopy has revealed that immune cell receptors are organized in nanoscale clusters at cell surfaces and immune synapses. However, mechanisms and functions for this nanoscale organization remain unclear. Here, we used super-resolution microscopy to compare the surface organization of paired killer Ig-like receptors (KIR, KIR2DL1 and KIR2DS1, on human primary natural killer cells and cell lines. Activating KIR2DS1 assembled in clusters two-fold larger than its inhibitory counterpart KIR2DL1. Site-directed mutagenesis established that the size of nanoclusters is controlled by transmembrane amino acid 233, a lysine in KIR2DS1. Super-resolution microscopy also revealed two ways in which the nanoscale clustering of KIR affects signaling. First, KIR2DS1 and DAP12 nanoclusters are juxtaposed in the resting cell state but coalesce upon receptor ligation. Second, quantitative super-resolution microscopy revealed that phosphorylation of the kinase ZAP-70 or phosphatase SHP-1 is favored in larger KIR nanoclusters. Thus, the size of KIR nanoclusters depends on the transmembrane sequence and affects downstream signaling.

  5. Anisoplanatism in adaptive optics systems due to pupil aberrations

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, B

    2005-08-01

    Adaptive optics systems typically include an optical relay that simultaneously images the science field to be corrected and also a set of pupil planes conjugate to the deformable mirror of the system. Often, in the optical spaces where DM's are placed, the pupils are aberrated, leading to a displacement and/or distortion of the pupil that varies according to field position--producing a type of anisoplanatism, i.e., a degradation of the AO correction with field angle. The pupil aberration phenomenon is described and expressed in terms of Seidel aberrations. An expression for anisoplanatism as a function of pupil distortion is derived, an example of an off-axis parabola is given, and a convenient method for controlling pupil-aberration-generated anisoplanatism is proposed.

  6. Bullying in Basic School: the Perspectives of Teachers and Pupils

    Directory of Open Access Journals (Sweden)

    Katja Posnic

    2016-06-01

    Full Text Available The main purpose of our study was to investigate how basic school pupils and teachers perceive and understand bullying. The participants in the study were 58 teachers and 396 pupils in basic school. The results indicate that both teachers and pupils perceive verbal bullying as the most frequent form of bullying compared to physical and relational bullying. Pupils report perceiving more bullying than teachers. Both pupils and teachers perceive physical and verbal bullying as more serious forms of bullying compared to relational bullying and report feeling more empathy toward victims of these two forms of bullying. In addition, teachers report that they are more willing to intervene in cases of physical and verbal bullying. There are significant differences between pupils’ and teachers’ reports of the likelihood of teachers’ interventions in cases of bullying; compared to pupils teachers report a higher likelihood of their intervention..

  7. INFLUENCE OF PHYSICAL BODY EXERCISES ON PUPILS

    Directory of Open Access Journals (Sweden)

    Mamaj Driton

    2015-05-01

    Full Text Available In the education system of Kosova, frequent changes that have occurred in last 14 years, have demonstrated that the education system has tried to adjust to economic, social and cultural changes, etc. As these changes have not been studied well, they have influenced and are still influencing organization of physical education in schools as regards their quality and quantity. These changes have not provided desired results and are often regarded as experiments. Methods: When defining the time, this study has longitudinal empirical character and consists of two measures, the morphological and motoric indicators in the pupils of primary school and lower secondary school “Faik Konica”. This study involved 26 pupils in the age group of 15 years. 6 anthropometric and 4 motoric variables have been applied (Kurelić et al, 1975. Anthropometric variables included: body height (ATV, length of foot (ADS, body mass (ATT, volume of upper arm in down position (AONL, volume of tight (AONK, volume of lower leg (AOPK. Motoric variables included: standing distance jump (MFESDM, 30 meters distance running (MTR30V, bench bending (MFLPRK and push-ups (MSKLEK. For data analysis t-test for dependent sample has been used. Results: Basic statistical parameters of the obtained results before and after the application of additional class of physical education indicate that the results have normal distribution, have no visible asymmetry and have tendency toward higher values of distribution (epikurtic. T-test analysis for dependent variable demonstrates that the obtained differences within all variables in the groups are statistically significant. Discussion: Physical activities and body exercises during sport education classes of three times per week have visible influence in development of morphologic parameters and motoric skills of pupils. Differences obtained based on the t-test analysis demonstrate a strong statistical difference for all variables applied

  8. Subcellular Size

    Science.gov (United States)

    Marshall, Wallace F.

    2015-01-01

    All of the same conceptual questions about size in organisms apply equally at the level of single cells. What determines the size, not only of the whole cell, but of all of its parts? What ensures that subcellular components are properly proportioned relative to the whole cell? How does alteration in organelle size affect biochemical function? Answering such fundamental questions requires us to understand how the size of individual organelles and other cellular structures is determined. Knowledge of organelle biogenesis and dynamics has advanced rapidly in recent years. Does this knowledge give us enough information to formulate reasonable models for organelle size control, or are we still missing something? PMID:25957302

  9. Test-retest repeatability of the pupil light response to blue and red light stimuli in normal human eyes using a novel pupillometer

    Directory of Open Access Journals (Sweden)

    Kristina eHerbst

    2011-02-01

    Full Text Available In this study, we evaluated the repeatability of pupil responses to colored light stimuli in healthy subjects using a prototype chromatic pupillometer. One eye of 10 healthy subjects was tested twice in the same day using monochromatic light exposure at 2 selected wavelengths (660 nm and 470 nm, intensity 300 cd/m2 presented continuously for 20 seconds. Pupil responses were recorded in real time before, during and after light exposure. Maximal contraction amplitude and sustained contraction amplitude were calculated. In addition, we quantified the summed pupil response during continuous light stimulation as the total area between a reference line representing baseline pupil size and the line representing actual pupil size over 20 seconds (area under the curve. There was no significant difference in the repeated measure compared to the first test for any of the pupil response parameters. In conclusion, we have developed a novel prototype of color pupillometer which demonstrates good repeatability in evoking and recording the pupillary response to a bright blue and red light stimulus.

  10. Discussing Terrorism: A Pupil-Inspired Guide to UK Counter-Terrorism Policy Implementation in Religious Education Classrooms in England

    Science.gov (United States)

    Quartermaine, Angela

    2016-01-01

    My research into pupils' perceptions of terrorism and current UK counter-terrorism policy highlights the need for more detailed and accurate discussions about the implementation of the educational aims, in particular those laid out by the Prevent Strategy. Religious education (RE) in England is affected by these aims, specifically the challenging…

  11. Discussing Terrorism: A Pupil-Inspired Guide to UK Counter-Terrorism Policy Implementation in Religious Education Classrooms in England

    Science.gov (United States)

    Quartermaine, Angela

    2016-01-01

    My research into pupils' perceptions of terrorism and current UK counter-terrorism policy highlights the need for more detailed and accurate discussions about the implementation of the educational aims, in particular those laid out by the Prevent Strategy. Religious education (RE) in England is affected by these aims, specifically the challenging…

  12. Development of a Short-Form Version of the Physical Education Classroom Instrument: Measuring Secondary Pupils' Disruptive Behaviours

    Science.gov (United States)

    Krech, Paul R.; Kulinna, Pamela H.; Cothran, Donetta

    2010-01-01

    Background: Effective classroom management is the cornerstone of successful teaching. Behavioural issues affect the classroom climate as well as the time available for learning. Pupil misbehaviours can also contribute to teacher stress and burn out resulting in teachers leaving the profession. It is important for us to understand more about pupil…

  13. The mind-writing pupil : A human-computer interface based on decoding of covert attention through pupillometry

    NARCIS (Netherlands)

    Mathôt, Sebastiaan; Melmi, Jean Baptiste; Van Der Linden, Lotje; Van Der Stigchel, Stefan

    2016-01-01

    We present a new human-computer interface that is based on decoding of attention through pupillometry. Our method builds on the recent finding that covert visual attention affects the pupillary light response: Your pupil constricts when you covertly (without looking at it) attend to a bright, compar

  14. The Mind-Writing Pupil : A Human-Computer Interface Based on Decoding of Covert Attention through Pupillometry

    NARCIS (Netherlands)

    Mathot, Sebastiaan; Melmi, Jean-Baptiste; van der Linden, Lotje; van der Stigchel, Stefan

    2016-01-01

    We present a new human-computer interface that is based on decoding of attention through pupillometry. Our method builds on the recent finding that covert visual attention affects the pupillary light response: Your pupil constricts when you covertly (without looking at it) attend to a bright, compar

  15. Training Teachers to Support Pupils' Listening in Class: An Evaluation Using Pupil Questionnaires

    Science.gov (United States)

    Crosskey, Liz; Vance, Maggie

    2011-01-01

    Many children with speech, language and communication needs are educated in mainstream schools. Current policy and practice includes training for school staff in facilitating the development of speaking and listening skills. This study evaluates one such training package that focuses on supporting pupils' listening skills, delivered in a…

  16. Pupil Control Ideology, Pupil Control Behavior and the Quality of School Life.

    Science.gov (United States)

    Lunenburg, Fred C.; Schmidt, Linda J.

    1989-01-01

    This article defines two approaches to pupil control--custodial and humanistic--and reports results of an investigation of the relationship between teacher control ideology and behavior and their influence on quality of life for students. Subjects were 239 elementary and secondary teachers and their students from 5 school districts. (IAH)

  17. Pupil mimicry correlates with trust in in-group partners with dilating pupils

    NARCIS (Netherlands)

    Kret, M.E.; Fischer, A.H.; de Dreu, C.K.W.

    2015-01-01

    During close interactions with fellow group members, humans look into one another’s eyes, follow gaze, and quickly grasp emotion signals. The eye-catching morphology of human eyes, with unique eye whites, draws attention to the middle part, to the pupils, and their autonomic changes, which signal ar

  18. Disruption of the cell wall lytic enzyme CwlO affects the amount and molecular size of poly-γ-glutamic acid produced by Bacillus subtilis (natto).

    Science.gov (United States)

    Mitsui, Nobuo; Murasawa, Hisashi; Sekiguchi, Junichi

    2011-01-01

    Poly-γ-glutamic acid (γPGA), a polymer of glutamic acid, is a component of the viscosity substance of natto, a traditional Japanese food made from soybeans fermented with Bacillus subtilis (natto). Here we investigate the effects of the cell wall lytic enzymes belonging to the D,L-endopeptidases (LytE, LytF, CwlO and CwlS) on γPGA production by B. subtilis (natto). γPGA levels in a cwlO disruptant were about twofold higher than that of the wild-type strain, whereas disruption of the lytE, lytF and cwlS genes had little effect on γPGA production. The molecular size of γPGA in the cwlO disruptant was larger than that of the wild-type strain. A complementary strain was constructed by insertion of the entire cwlO gene into the amyE locus of the CwlO mutant genome, and γPGA production was restored to wild-type levels in this complementary strain. These results indicated that the peptidoglycan degradation enzyme, CwlO, plays an important role in γPGA production and affects the molecular size of γPGA.

  19. Sperm competition and the evolution of precopulatory weapons: Testis size and amplexus position, but not arm strength, affect fertilization success in a chorusing frog.

    Science.gov (United States)

    Buzatto, Bruno A; Thyer, Evan M; Roberts, J Dale; Simmons, Leigh W

    2017-02-01

    Trade-offs between pre- and postcopulatory traits influence their evolution, and male expenditure on such traits is predicted to depend on the number of competitors, the benefits from investing in weapons, and the risk and intensity of sperm competition. Males of the chorusing frog Crinia georgiana use their arms as weapons in contest competition. Previously, we showed that increased numbers of rivals elevated the risk and intensity of sperm competition due to multimale amplexus, and caused a reversal in the direction of precopulatory selection on arm girth. Here, we focused on the factors affecting postcopulatory fertilization success during group spawning, using paternity data from natural choruses. Competitive fertilization success depended on the time spent amplexed and amplexus position. Relative testes size but not arm girth, contributed to fertilization success, but the effect of testes size depended on amplexus position. Our findings offer within species empirical support for recent sperm competition models that incorporate precopulatory male-male competition, and show why an understanding of the evolution of animal weapons requires a consideration of both pre- and postcopulatory episodes of sexual selection.

  20. Pupil rotation compensation for LINC-NIRVANA

    Science.gov (United States)

    Brangier, Matthieu; Conrad, Albert R.; Bertram, Thomas; Zhang, Xianyu; Berwein, Juergen; Briegel, Florian; Herbst, Thomas M.; Ragazzoni, Roberto

    2012-07-01

    The interferometric imager LINC-NIRVANA will use pyramid wavefront-sensors for multi-conjugated adaptive optics (MCAO). A derotator will produce a static field on the pyramids, but a rotating pupil image on the CCD. For long exposure times, we have to take into account this effect to command the deformable mirror properly by changing the command matrix on the fly. We reproduce in a laboratory set-up this configuration to test different methods for compensating for this effect. We present the results obtained and the optimal solution we have selected.

  1. Teaching High-Ability Pupils in Early Primary School

    NARCIS (Netherlands)

    Dijkstra, Elma

    2015-01-01

    This thesis describes the design and implementation of the intervention 'Excel Kwadraat' in primary schools. This intervention aims to improve teachers’ differentiation practices in order to better anticipate pupil differences, including excellent or high-ability pupils. In the end, the intervention

  2. Knowledge and Experiences of Risks among Pupils in Vocational Education

    Directory of Open Access Journals (Sweden)

    Ing-Marie Andersson

    2014-09-01

    Conclusion: A systematic approach to pupils' training in work environment, which is a basis for a safe and healthy workplace, is lacking. The study findings indicate that pupils are offered knowledge far from that intended by laws and by state-of-the-art occupational health risk research.

  3. EFFICIENCY OF READING COMPREHENSION TRAINING IN PUPILS LIVING IN POVERTY

    Directory of Open Access Journals (Sweden)

    Milena Kosak Babuder

    2015-09-01

    Full Text Available The results of Slovene and foreign studies reveal the connection between literacy levels and the level of education, employment opportunities and consequent socio-economic status of individuals and families. Reading efficiency relating to reading comprehension is an important element of reading literacy performance. The findings of several authors indicate empirical evidence of the existence of deficits and poor reading comprehension in pupils living in poverty and stress the importance of offsetting deficits and developing reading comprehension. Results of both foreign and Slovene studies indicate that the program of reading comprehension should be implemented in this group of pupils. In the article, we want to present effectiveness of the reading comprehension improvement program in pupils living in poverty. According to the findings of our research, in which we structured and implemented the reading comprehension program for pupils living in poverty with the Metacognitive-intersentential model of reading comprehension, the reading comprehension of the experimental group pupils who participated in the program improved compared to the control group pupils who did not participate in the program. Experimental group pupils also significantly improved correctness of their reading, their vocabulary and skills of verbal expression. When the program ended, we tested its efficiency by applied tests. The results on the manifest variables indicated that the program was good and efficient for pupils who live in poverty and experience reading comprehension problems.

  4. Pupil segmentation using active contour with shape prior

    Science.gov (United States)

    Ukpai, Charles O.; Dlay, Satnam S.; Woo, Wai L.

    2015-03-01

    Iris segmentation is the process of defining the valid part of the eye image used for further processing (feature extraction, matching and decision making). Segmentation of the iris mostly starts with pupil boundary segmentation. Most pupil segmentation techniques are based on the assumption that the pupil is circular shape. In this paper, we propose a new pupil segmentation technique which combines shape, location and spatial information for accurate and efficient segmentation of the pupil. Initially, the pupil's position and radius is estimated using a statistical approach and circular Hough transform. In order to segment the irregular boundary of the pupil, an active contour model is initialized close to the estimated boundary using information from the first step and segmentation is achieved using energy minimization based active contour. Pre-processing and post-processing were carried out to remove noise and occlusions respectively. Experimental results on CASIA V1.0 and 4.0 shows that the proposed method is highly effective at segmenting irregular boundaries of the pupil.

  5. Formal Teacher Competence and Its Effect on Pupil Reading Achievement

    Science.gov (United States)

    Johansson, Stefan; Myrberg, Eva; Rosén, Monica

    2015-01-01

    The main aim of this study was to investigate the impact of formal teacher competence on pupils' reading achievement. The data comes from the Swedish participation in PIRLS 2001 in grade 3. Information was obtained from pupils (n = 5271) and teachers (n = 351). The analyses were conducted using 2-level structural equation modeling. Teacher…

  6. Inclusive School Is (Not) Possible--Pupil's Voice

    Science.gov (United States)

    Pavlovic, Slavica

    2016-01-01

    Inclusive education has been the focus of a number of research studies in Bosnia and Herzegovina. However, most of the research was based on the teachers and to a lesser extent on parents' attitudes towards inclusive education, while pupils' views and voice were mainly neglected. The core of this paper is survey research on primary school pupils'…

  7. Pupils' Documentation Enlightening Teachers' Practical Theory and Pedagogical Actions

    Science.gov (United States)

    Niemi, Reetta; Kumpulainen, Kristiina; Lipponen, Lasse

    2015-01-01

    This article is based on a pedagogical action research initiative comprising two research cycles. The study explores what constitutes meaningful experiences in the classroom from the pupils' perspectives and how understanding pupils' perspectives can foster the development of teachers' practical theory and classroom actions. Photography and group…

  8. An Empirical Study of Pupils' Attitudes to Computers and Robots.

    Science.gov (United States)

    Moore, J. L.

    1985-01-01

    Describes a study which utilized a Likert type questionnaire to assess seven scales of secondary pupils' attitudes toward computers and robotics (school, leisure, career, employment, social, threat, future) and investigated pupils' scores on functions of their sex, general academic ability, course of study, and microcomputer experience. (MBR)

  9. Teaching High-Ability Pupils in Early Primary School

    NARCIS (Netherlands)

    Dijkstra, Elma

    2015-01-01

    This thesis describes the design and implementation of the intervention 'Excel Kwadraat' in primary schools. This intervention aims to improve teachers’ differentiation practices in order to better anticipate pupil differences, including excellent or high-ability pupils. In the end, the intervention

  10. Understanding Pupil Behaviour: Classroom Management Techniques for Teachers

    Science.gov (United States)

    Lewis, Ramon

    2009-01-01

    This book describes a system of successful classroom behaviour management techniques developed by the author over more than twenty-five years. It outlines the difficulties confronting teachers trying to manage pupils' misbehaviour in schools and describes four types of pupil who can be helped to behave responsibly. In "Understanding Pupil…

  11. Perspective reports of corporal punishment by pupils in Lesotho schools.

    Science.gov (United States)

    Monyooe, L A

    1993-10-01

    This study surveyed reports of practices of corporal punishment at secondary schools in Lesotho by 60 randomly selected pupils. There were 34 males and 26 females, whose mean age was 21 years, with a range between 14 and 29 years. Responses to a questionnaire confirmed that punishment was associated with pupils' reports of academic impairment, psychological damage, and physical injury.

  12. Primary School Pupils' Performances in Understanding Historical Time

    Science.gov (United States)

    de Groot-Reuvekamp, Marjan; Ros, Anje; van Boxtel, Carla; Oort, Frans

    2017-01-01

    This study focuses on the development of the understanding of historical time of pupils in primary school. We present a developmental model with three stages: "emergent," "initial" and "continued" understanding of historical time. Based on this model, we constructed an instrument to measure how pupils aged 6-12…

  13. Roma Pupils' Attitudes Towards Education--A Case Study

    Science.gov (United States)

    Pecek, Mojca; Munda, Milanka

    2015-01-01

    When analysing the reasons behind the academic underachievement of Roma pupils, some teachers suggest that Roma people do not value education and that Roma children have negative attitudes towards school. With increasing frequency, Roma pupils from low socio-economic backgrounds are being researched and the research primarily adopts the…

  14. Learning: What Do Primary Pupils Think about It?

    Science.gov (United States)

    Sahin Taskin, Cigdem

    2012-01-01

    The author aimed to explore primary pupils' perceptions of learning and to what extent they perceive learning is important to them. Fifty-five primary school pupils in Istanbul and Canakkale (Turkey) were interviewed. To analyze the data, A. Strauss and J. Corbin's (1998) grounded theory methodology was followed. NVivo 7 (QSR, Australia) a…

  15. Pupils' Word Choices and the Teaching of Grammar

    Science.gov (United States)

    Wyse, Dominic

    2006-01-01

    The idea that formal grammar teaching leads to improvements in school pupils' writing has been a popular one. However, the robust and extensive evidence base shows that this is not the case. Despite this, policy initiatives have continued to suggest that grammar teaching does improve pupils' writing: the "Grammar for Writing" resource is the most…

  16. Results of a Survey of Pupils and Teachers Regarding Television.

    Science.gov (United States)

    Crawford, Patricia; Rapoport, Max

    To test the validity of hypotheses regarding television violence and social behavior of viewers, a survey was conducted of a large stratified sample of sixth grade and kindergarten pupils and of teachers. The student survey identified: (1) frequency with which pupils watch television; (2) parental control of television viewing; (3) family…

  17. Pupils' Plans to Study Abroad: Social Reproduction of Transnational Capital?

    NARCIS (Netherlands)

    Weenink, D.; Gerhards, J.; Hans, S.; Carlson, S.

    2013-01-01

    This chapter analyses Dutch pupils' plans to study abroad. The main question is to what extent these plans are related to their social class position, their parents' and their own transnational capital and the school type they attend. The analyses are based on survey data of 549 Dutch pupils, aged

  18. Pupil Culture, Peer Tutoring and Special Educational Needs.

    Science.gov (United States)

    Quicke, J. C.

    1986-01-01

    Most existing studies of pupil-pupil interactions in special education have been psychology-based and have not considered the significance of students' social background. An ethnographic study examined the attitudes of academic and remedial British secondary students toward handicapped or otherwise deviant students. Results raised questions about…

  19. Does Lego Training Stimulate Pupils' Ability to Solve Logical Problems?

    Science.gov (United States)

    Lindh, Jorgen; Holgersson, Thomas

    2007-01-01

    The purpose of this study is to investigate the effect of a one-year regular robotic toys (lego) training on school pupils' performance. The underlying pedagogical perspective is the "constructionist theory," where the main idea is that knowledge is constructed in the mind of the pupil by active learning. The investigation has been made…

  20. The Impact of "Sesame Street" on Primary Pupils in Vancouver.

    Science.gov (United States)

    Ellis, E. N.; And Others

    The extent to which pupils at the primary level view Sesame Street and The Electric Company television programs and their impact on learning were studied. Questionnaires were directed to parents of children in eight kindergartens and to principals of the 34 elementary schools in Vancouver. At their homes, 95% of the kindergarten pupils had watched…

  1. Roma Pupils' Attitudes Towards Education--A Case Study

    Science.gov (United States)

    Pecek, Mojca; Munda, Milanka

    2015-01-01

    When analysing the reasons behind the academic underachievement of Roma pupils, some teachers suggest that Roma people do not value education and that Roma children have negative attitudes towards school. With increasing frequency, Roma pupils from low socio-economic backgrounds are being researched and the research primarily adopts the…

  2. Design of a Binocular Pupil and Gaze Point Detection System Utilizing High Definition Images

    Directory of Open Access Journals (Sweden)

    Yilmaz Durna

    2017-05-01

    Full Text Available This study proposes a novel binocular pupil and gaze detection system utilizing a remote full high definition (full HD camera and employing LabVIEW. LabVIEW is inherently parallel and has fewer time-consuming algorithms. Many eye tracker applications are monocular and use low resolution cameras due to real-time image processing difficulties. We utilized the computer’s direct access memory channel for rapid data transmission and processed full HD images with LabVIEW. Full HD images make easier determinations of center coordinates/sizes of pupil and corneal reflection. We modified the camera so that the camera sensor passed only infrared (IR images. Glints were taken as reference points for region of interest (ROI area selection of the eye region in the face image. A morphologic filter was applied for erosion of noise, and a weighted average technique was used for center detection. To test system accuracy with 11 participants, we produced a visual stimulus set up to analyze each eye’s movement. Nonlinear mapping function was utilized for gaze estimation. Pupil size, pupil position, glint position and gaze point coordinates were obtained with free natural head movements in our system. This system also works at 2046 × 1086 resolution at 40 frames per second. It is assumed that 280 frames per second for 640 × 480 pixel images is the case. Experimental results show that the average gaze detection error for 11 participants was 0.76° for the left eye, 0.89° for right eye and 0.83° for the mean of two eyes.

  3. Correcting for the effects of pupil discontinuities with the ACAD method

    Science.gov (United States)

    Mazoyer, Johan; Pueyo, Laurent; N'Diaye, Mamadou; Mawet, Dimitri; Soummer, Rémi; Norman, Colin

    2016-07-01

    The current generation of ground-based coronagraphic instruments uses deformable mirrors to correct for phase errors and to improve contrast levels at small angular separations. Improving these techniques, several space and ground based instruments are currently developed using two deformable mirrors to correct for both phase and amplitude errors. However, as wavefront control techniques improve, more complex telescope pupil geometries (support structures, segmentation) will soon be a limiting factor for these next generation coronagraphic instruments. The technique presented in this proceeding, the Active Correction of Aperture Discontinuities method, is taking advantage of the fact that most future coronagraphic instruments will include two deformable mirrors, and is proposing to find the shapes and actuator movements to correct for the effect introduced by these complex pupil geometries. For any coronagraph previously designed for continuous apertures, this technique allow to obtain similar performance in contrast with a complex aperture (with segmented and secondary mirror support structures), with high throughput and flexibility to adapt to changing pupil geometry (e.g. in case of segment failure or maintenance of the segments). We here present the results of the parametric analysis realized on the WFIRST pupil for which we obtained high contrast levels with several deformable mirror setups (size, separation between them), coronagraphs (Vortex charge 2, vortex charge 4, APLC) and spectral bandwidths. However, because contrast levels and separation are not the only metrics to maximize the scientific return of an instrument, we also included in this study the influence of these deformable mirror shapes on the throughput of the instrument and sensitivity to pointing jitters. Finally, we present results obtained on another potential space based telescope segmented aperture. The main result of this proceeding is that we now obtain comparable performance than the

  4. Formulation of Word Problems in Geometry by Gifted Pupils

    Directory of Open Access Journals (Sweden)

    Ilana LEVENBERG

    2014-12-01

    Full Text Available This study investigated the ability level of talented and gifted pupils to define selected geometry terms and formulate a word problem for each of them. In order to perform this task correctly, pupils should be acquainted with the geometry term. Moreover, they must have at last experience in solving word problems. The research population consisted of 58 pupils from the 4th-6th grades who learn mathematics in a course which is adjusted to their high ability level. The research findings illustrate a medium level of mastery of the term definition knowledge. The formulated word problems were mainly taken from the pupils' previous experience and they are at the first level according to van Hiele. Only few pupils demonstrated creativity and write problems which were not similar to the ones they knew from the textbooks.

  5. Exoplanet detection with simultaneous spectral differential imaging: effects of out-of-pupil-plane optical aberrations

    CERN Document Server

    Marois, C; Marois, Christian; Macintosh, Don W. Phillion & Bruce

    2006-01-01

    Imaging faint companions (exoplanets and brown dwarfs) around nearby stars is currently limited by speckle noise. To efficiently attenuate this noise, a technique called simultaneous spectral differential imaging (SSDI) can be used. This technique consists of acquiring simultaneously images of the field of view in several adjacent narrow bands and in combining these images to suppress speckles. Simulations predict that SSDI can achieve, with the acquisition of three wavelengths, speckle noise attenuation of several thousands. These simulations are usually performed using the Fraunhofer approximation, i.e. considering that all aberrations are located in the pupil plane. We have performed wavefront propagation simulations to evaluate how out-of-pupil-plane aberrations affect SSDI speckle noise attenuation performance. The Talbot formalism is used to give a physical insight of the problem; results are confirmed using a proper wavefront propagation algorithm. We will show that near-focal-plane aberrations can sig...

  6. [Staphylococcus aureus prevalence among preschool- and school-aged pupils].

    Science.gov (United States)

    Pavilonyte, Zaneta; Kacerauskiene, Justina; Budryte, Brigita; Keizeris, Tadas; Junevicius, Jonas; Pavilonis, Alvydas

    2007-01-01

    To determine the prevalence and incidence of Staphylococcus aureus strains among preschool- and school-aged pupils and susceptibility of these strains to antimicrobial materials. A study of 243 preschool- and 300 school-aged pupils was conducted during 2003-2004. Identification of Staphylococcus aureus was made with plasmacoagulase and DNase tests. The resistance of Staphylococcus aureus to antibiotics, beta-lactamase activity, phagotypes, and phage groups were determined. The isolated Staphylococcus aureus strains were tested for resistance to methicillin by performing disc diffusion method using commercial discs (Oxoid) (methicillin 5 microg per disk and oxacillin 1 microg per disk). A total of 292 (53.8%) Staphylococcus aureus strains were isolated and identified (113 (46.5%) from preschool- and 179 (59.7%) from school-aged pupils). The prevalence of Staphylococcus aureus strains among preschool-aged pupils varied from 46.5% to 47%. It increased to 59.0% (P>0.05) among schoolchildren aged from 11 to 15 years and to 73.0% (Ppreschool-aged and four (2.2%) from school-aged pupils. The prevalence of Staphylococcus aureus strains with beta-lactamase activity increased from 70.7 to 76.6% in preschool-aged pupils, and it varied from 72.0 to 79.0% in school-aged pupils (P>0.05). Staphylococcus aureus strains of phage group II (32.2-43.4%) were prevailing; nontypable Staphylococcus aureus strains made up 19.2-33.6%. The prevalence of Staphylococcus aureus among preschool-aged children is 41.7 to 48.8%, and it increases among 9th-12th-grade pupils (73.0%, Ppreschool- and school-aged pupils. Pupils were colonized with methicillin-resistant Staphylococcus aureus strains belonging to phage group III phagotype 83A and 77.

  7. Pupil Researchers Generation X: Educating Pupils as Active Participants--An Investigation into Gathering Sensitive Information from Early Adolescents

    Science.gov (United States)

    Symonds, Jenny E.

    2008-01-01

    Developmentally appropriate research techniques were uncovered by involving ten Year 7 pupils as researchers in a four-hour workshop that investigated the effectiveness of multiple methods in gathering sensitive information from early adolescents. The pupils learned about, tried and evaluated the methods of generating interview questions, peer and…

  8. Atorvastatin treatment lowers fasting remnant-like particle cholesterol and LDL subfraction cholesterol without affecting LDL size in type 2 diabetes mellitus: Relevance for non-HDL cholesterol and apolipoprotein B guideline targets

    NARCIS (Netherlands)

    P.J.W.H. Kappelle; G.M. Dallinga-Thie; R.P.F. Dullaart

    2010-01-01

    The extent to which atorvastatin treatment affects LDL size, LDL subfraction levels and remnant-like particle cholesterol (RLP-C) was determined in type 2 diabetes. We also compared LDL size and RLP-C in relation to guideline cut-off values for LDL cholesterol, non-HDL cholesterol and apolipoprotein

  9. Atorvastatin treatment lowers fasting remnant-like particle cholesterol and LDL subfraction cholesterol without affecting LDL size in type 2 diabetes mellitus : Relevance for non-HDL cholesterol and apolipoprotein B guideline targets

    NARCIS (Netherlands)

    Kappelle, Paul J.W.H.; Dallinga-Thie, Geesje M.; Dullaart, Robin P. F.

    The extent to which atorvastatin treatment affects LDL size, LDL subfraction levels and remnant-like particle cholesterol (RLP-C) was determined in type 2 diabetes. We also compared LDL size and RLP-C in relation to guideline cut-off values for LDL cholesterol, non-HDL cholesterol and apolipoprotein

  10. Atorvastatin treatment lowers fasting remnant-like particle cholesterol and LDL subfraction cholesterol without affecting LDL size in type 2 diabetes mellitus : Relevance for non-HDL cholesterol and apolipoprotein B guideline targets

    NARCIS (Netherlands)

    Kappelle, Paul J.W.H.; Dallinga-Thie, Geesje M.; Dullaart, Robin P. F.

    2010-01-01

    The extent to which atorvastatin treatment affects LDL size, LDL subfraction levels and remnant-like particle cholesterol (RLP-C) was determined in type 2 diabetes. We also compared LDL size and RLP-C in relation to guideline cut-off values for LDL cholesterol, non-HDL cholesterol and apolipoprotein

  11. Low pH affects survival, growth, size distribution, and carapace quality of the postlarvae and early juveniles of the freshwater prawn Macrobrachium rosenbergii de Man

    Science.gov (United States)

    Kawamura, Gunzo; Bagarinao, Teodora; Yong, Annita Seok Kian; Chen, Chiau Yu; Noor, Siti Norasidah Mat; Lim, Leong Seng

    2015-06-01

    Acidification of rain water caused by air pollutants is now recognized as a serious threat to aquatic ecosystems. We examined the effects of low pH (control pH 7.5, pH 6, pH 5, pH 4) on the survival, growth, and shell quality of Macrobrachium rosenbergii postlarvae and early juveniles in the laboratory. Hatcheryproduced postlarvae (PL 5) were stocked at 250 PL per aquarium, acclimated over 7 d to experimental pH adjusted with hydrochloric acid, and reared for 30 d. Dead specimens were removed and counted twice a day. After 27 d rearing, all specimens were measured for total length and body weight. Carapace quality was assessed by spectrophotometry. Survival of juveniles was highest at pH 6 (binomial 95% confidence interval 79 - 89%) followed by control pH 7.5 (56 - 68%) and pH 5 (50 - 60%) and was lowest for unmetamorphosed postlarvae and juveniles at pH 4 (43 - 49%). The final median total length and body weight of juveniles were similar at control pH 7.5 (18.2 TL, 50.2 mg BW) and pH 6 (17.7 mm TL, 45.0 mg BW) but significantly less at pH 5 (16.7 mm TL, 38.2 mg BW); at pH 4, the postlarvae did not metamorphose and measured only 9.8 mm TL, 29.3 mg BW. Length frequency distribution showed homogeneous growth at pH 6, positive skew at control pH 7.5 and pH 5, and extreme heterogeneity at pH 4. The carapace showed different transmittance spectra and lower total transmittance (i.e. thicker carapace) in juveniles at pH 7.5, pH 6, and pH 5 than in unmetamorphosed postlarvae and juveniles with thinner carapace at pH 4. Thus, survival, growth, size distribution, and carapace quality of M. rosenbergii postlarvae and early juveniles were negatively affected by pH 5 and especially pH 4. The thinner carapace of the survivors at pH 4 was mostly due to their small size and failure to metamorphose. Natural waters affected by acid rain could decimate M. rosenbergii populations in the wild.

  12. Performance improvement of super-resolving pupil filters via combination with nonlinear saturable absorption films

    Science.gov (United States)

    Zha, Yikun; Wei, Jingsong; Gan, Fuxi

    2013-04-01

    With the continuous development of the field of information technology, there has been a demand for recording mark size of optical data storage, optical imaging resolving power, and characteristic linewidth of photolithography to reach nanoscale. However, it is very difficult to realize the goal due to the optical diffraction limit restrictions. Much interest has focused on the study of optical far-field super-resolution spot by using pupil filters. However, common concerns have continued to plague super-resolving pupil filters based on either scalar diffraction theory or vector diffraction theory. These concerns include the fact that the side lobe becomes non-negligible when the central lobe is squeezed to a certain extent. Moreover, it is difficult to reduce the super-resolving spot to nanoscale. In this work, we proposed a novel method to combine the super-resolving pupil filters with nonlinear saturable absorption thin films to reduce the central spot size to nanoscale, lower the intensity ratio of side lobe to central lobe, and elongate the depth of focus or tunable tolerance distance between the super-resolving spot and sample. The simulated results indicate that by using the three-zone annular binary phase filter as the super-resolving pupil filter and Sb2Te3 as the nonlinear saturable absorption thin films, the central spot size can be reduced to nanoscale, the side lobe intensity is squeezed to about 10% of the central lobe intensity, and the tunable tolerance distance between the super-resolving spot and the sample is about two times that of the depth of focus of the diffraction limited spot at the incident laser wavelength of 405 nm and the numerical aperture of focusing lens of 0.95. The combination of the super-resolving pupil filters with the nonlinear saturable absorption thin films is very useful for nano-optical data storage, maskless nanolithography, and nano-optical imaging. It is also easy to use in actual applications because of the operation

  13. Development of Items for a Pedagogical Content Knowledge Test Based on Empirical Analysis of Pupils' Errors

    Science.gov (United States)

    Jüttner, Melanie; Neuhaus, Birgit J.

    2012-05-01

    In view of the lack of instruments for measuring biology teachers' pedagogical content knowledge (PCK), this article reports on a study about the development of PCK items for measuring teachers' knowledge of pupils' errors and ways for dealing with them. This study investigated 9th and 10th grade German pupils' (n = 461) drawings in an achievement test about the knee-jerk in biology, which were analysed by using the inductive qualitative analysis of their content. The empirical data were used for the development of the items in the PCK test. The validation of the items was determined with think-aloud interviews of German secondary school teachers (n = 5). If the item was determined, the reliability was tested by the results of German secondary school biology teachers (n = 65) who took the PCK test. The results indicated that these items are satisfactorily reliable (Cronbach's alpha values ranged from 0.60 to 0.65). We suggest a larger sample size and American biology teachers be used in our further studies. The findings of this study about teachers' professional knowledge from the PCK test could provide new information about the influence of teachers' knowledge on their pupils' understanding of biology and their possible errors in learning biology.

  14. Pupil measures of alertness and mental load

    Science.gov (United States)

    Backs, Richard W.; Walrath, Larry C.

    1988-01-01

    A study of eight adults given active and passive search tasks showed that evoked pupillary response was sensitive to information processing demands. In particular, large pupillary diameter was observed in the active search condition where subjects were actively processing information relevant to task performance, as opposed to the passive search (control) condition where subjects passively viewed the displays. However, subjects may have simply been more aroused in the active search task. Of greater importance was that larger pupillary diameter, corresponding to longer search time, was observed for noncoded than for color-coded displays in active search. In the control condition, pupil diameter was larger with the color displays. The data indicate potential usefulness of pupillary responses in evaluating the information processing requirements of visual displays.

  15. Generalized pupil aberrations of optical imaging systems

    Science.gov (United States)

    Elazhary, Tamer T.

    In this dissertation fully general conditions are presented to correct linear and quadratic field dependent aberrations that do not use any symmetry. They accurately predict the change in imaging aberrations in the presence of lower order field dependent aberrations. The definitions of the image, object, and coordinate system are completely arbitrary. These conditions are derived using a differential operator on the scalar wavefront function. The relationships are verified using ray trace simulations of a number of systems with varying degrees of complexity. The math is shown to be extendable to provide full expansion of the scalar aberration function about field. These conditions are used to guide the design of imaging systems starting with only paraxial surface patches, then growing freeform surfaces that maintain the analytic conditions satisfied for each point in the pupil. Two methods are proposed for the design of axisymmetric and plane symmetric optical imaging systems. Design examples are presented as a proof of the concept.

  16. Engaging Parents and Pupils in Astronomy

    Science.gov (United States)

    Stevenson, Rod

    2016-04-01

    "The British National Space Centre partnership has recognised for some time that Space and Astronomy are particularly attractive subjects for school students and that including these in the science curriculum can have a positive effect on student interest in science. Drivers are that the number of young people studying science and engineering subjects at A-level and beyond is declining; young people should have an understanding of the importance of science and technology to the world around them; and that UK space industry (including technology, engineering, space science, Earth observation science) must renew itself." BRINGING SPACE INTO SCHOOL Professor Martin Barstow, University of Leicester Published by PPARC on behalf of the British National Space Centre Partnership October 2005 "It has become more and more difficult to persuade young people to follow a career in STEM (Science, Technology, Engineering & Mathematics) subjects. Across the EU, the number of graduates in STEM subjects has dropped from 24.3% in 2002 to 22.6% in 2011" (Source EUSTAT) It was Martin Barstow's report in 2005 that started my attempt to interest people in Science and Technology, At Ormiston Victory Academy (OVA) for the past two years, we have embarked on a program to enthuse pupils to study science related subject through the medium of Astronomy. We teach Edexcel GCSE Astronomy to a joint parent and pupil group. They study together and at the end of the course, both take the GCSE examination. The idea is that the pupils see that science is important to their parents and that a very practical facet of science is also fun. Astronomy is a multidisciplinary course bringing together elements of Science, Maths, Technology, Geography and History. It is hoped that the enthusiasm shown by the pupils will spill over into the mainstream subjects including maths. The parents get an idea of the work and level of knowledge required by their children to complete a GCSE level subject. They also report

  17. Ethnic School Segregation and Self-Esteem: The Role of Teacher-Pupil Relationships

    Science.gov (United States)

    Agirdag, Orhan; Van Houtte, Mieke; Van Avermaet, Piet

    2012-01-01

    The authors examine whether school segregation is related to pupils' global self-esteem and whether this association is mediated by teacher-pupil relationships. Multilevel analyses based on a survey of 2,845 pupils (aged 10 to 12) in 68 primary schools in Belgian urban areas reveal that, for native-Belgian pupils, a higher proportion of immigrants…

  18. Hardware implementation of fast pupil segmentation using region properties

    Science.gov (United States)

    Khan, Taiq M.; Kong, Yinan; Khan, Muhammad A. U.

    2015-04-01

    This paper presents a novel approach for automatic pupil segmentation. The proposed algorithm uses local histogram-based threshold, area and eccentricity that looks for the region that has the highest probability of having the pupil. Proposed algorithm is implemented on FPGA using a non-iterative scheme along with hardware optimized median filter and connected component logic algorithm. The proposed algorithm is tested on two public databases namely: CASIA v1.0 and MMU v1.0. Experimental results show that the proposed method has satisfying performance and good robustness against the reflection in the pupil.

  19. Monitoring the Achievement of Deaf Pupils in Sweden and Scotland

    DEFF Research Database (Denmark)

    Hendar, Nils Ola Ebbe; O'Neill, Rachel

    2016-01-01

    patterns of achievements of deaf pupils to see if these reforms had improved attainment outcomes. International surveys such as PISA do not include deaf pupils. This article describes two independent large-scale surveys about deaf pupils in Sweden and Scotland. The similar results from both countries show...... the field to narrow the achievement gap further. The results further suggest that differing methods in two contrasting educational contexts can lead to some similar results and point to the need for different support to children with hearing loss and language disadvantages....

  20. The influence of school culture on smoking among pupils.

    Science.gov (United States)

    Aveyard, Paul; Markham, Wolfgang A; Lancashire, Emma; Bullock, Alison; Macarthur, Christine; Cheng, K K; Daniels, Harry

    2004-05-01

    School factors and not solely pupil composition probably cause variation in smoking prevalence amongst schools, but there are no theoretical models to explain why. In this paper we propose a hypothesis to explain schools' influence on pupils' smoking and test this using an existing cross-sectional survey of 23,282 pupils from 166 secondary schools in the West Midlands, UK. We hypothesise that school-level educational achievement scores would not be associated with smoking prevalence, but schools providing value-added education given the social background of pupils (authoritative schools) would provide effective support and control, have a relatively strong influence on pupils' lives and be associated with lower than average smoking prevalence. Schools providing value-denuded education (laissez-faire schools) would have a relatively weak influence on pupils' lives and be associated with higher than average smoking prevalence. The school achievement measures were the proportion of pupils achieving 5A-C General Certificates of Secondary Education (5A-Cs) grades and the proportion of half days lost to truancy. Value-added/denuded terms were created by regressing 5A-Cs and truancy on five markers of the social profile of pupils at the school. Authoritative schools achieved better than expected rates on both measures. Laissez-faire schools achieved worse than expected rates on both measures. All other schools were classed as indeterminate. Multilevel logistic regression was used to relate the risk of regular smoking to school culture in both achievement and authoritative/laissez-faire terms, both with and without adjustment for pupil-level risk factors for smoking. As predicted, schools' achievement measures were unrelated to pupils' smoking. The odds ratios (95% confidence intervals) for smoking in authoritative and laissez-faire schools relative to indeterminate schools were 0.80 (0.70-0.91) and 1.16 (1.07-1.27), respectively. Adjustment for pupil-level smoking risk

  1. Holographic analysis of dispersive pupils in space--time optics

    Energy Technology Data Exchange (ETDEWEB)

    Calatroni, J.; Vienot, J.C.

    1981-06-01

    Extension of space--time optics to objects whose transparency is a function of the temporal frequency v = c/lambda is examined. Considering the effects of such stationary pupils on white light waves, they are called temporal pupils. It is shown that simultaneous encoding both in the space and time frequency domains is required to record pupil parameters. The space-time impulse response and transfer functions are calculated for a dispersive nonabsorbent material. An experimental method providing holographic recording of the dispersion curve of any transparent material is presented.

  2. Fixed and dilated: the history of a classic pupil abnormality.

    Science.gov (United States)

    Koehler, Peter J; Wijdicks, Eelco F M

    2015-02-01

    The aim of this study was to investigate the development of ideas about the nature and mechanism of the fixed dilated pupil, paying particular attention to experimental conditions and clinical observations in the 19th century. Starting from Kocher's standard review in 1901, the authors studied German, English, and French texts for historical information. Medical and neurological textbooks from the 19th and 20th centuries were reviewed to investigate when and how this information percolated through neurological and neurosurgical practices. Cooper experimented with intracranial pressure (ICP) in a dog in the 1830s, but did not mention the pupils. He described dilated pupils in clinical cases without referring to the effect of light. Bright demonstrated to have some knowledge of the pupil sign (clinical observations). Realizing the unreliability of the pupil sign, Hutchinson in 1867-1868 tried to reason in which cases trepanation would be advisable. Von Leyden's 1866 animal experiments, in which he increased CSF volume by injecting protein solutions intracranially, was the first observation in which the association between fixed dilated pupils and increased ICP was established. Along with bradycardia and motor and respiratory effects, he noticed wide pupils were usually present in a comatose state. Asymmetrical dilation could not always be attributed to increased ICP, but to an oculomotor nerve lesion. Pagenstecher in 1871 extended knowledge by meticulously studying consecutive pupil phenomena with increasing pressure. In 1880, von Bergmann emphasized the significance of the ipsilateral dilation in experiments as well as in clinical cases. He distinguished the extent of pressure increase and its duration. Probably confusing irritation (epileptic head turning to the other side with pupil dilation) and lesion effects, he suggested a cortical area responsible for oculomotor phenomena, indicating what is now known as the frontal eye field. Naunyn and Schreiber (1881

  3. Super-resolution with Toraldo pupils: analysis with electromagnetic numerical simulations

    Science.gov (United States)

    Olmi, Luca; Bolli, Pietro; Cresci, Luca; Mugnai, Daniela; Natale, Enzo; Nesti, Renzo; Panella, Dario; Stefani, Lorenzo

    2016-07-01

    The concept of super-resolution refers to various methods for improving the angular resolution of an optical imaging system beyond the classical diffraction limit. In optical microscopy, several techniques have been developed with the aim of narrowing the central lobe of the illumination Point Spread Function (PSF). In Astronomy a few methods have been proposed to achieve reflector telescopes and antennas with resolution significantly better than the diffraction limit but, to our best knowledge, no working system is in operation. A possible practical approach consists of using the so-called "Toraldo Pupils" (TPs) or variable transmittance filters. These pupils were introduced by G. Toraldo di Francia in 1952,1 and consist of a series of discrete, concentric circular coronae providing specific optical transparency and dephasing in order to engineer the required PSF. The first successful laboratory test of TPs in the microwaves was achieved in 2003,2 and in the present work we build upon these initial measurements to perform electromagnetic (EM) numerical simulations of TPs, using a commercial full-wave software tool. These simulations were used to study various EM effects that can mask and/or affect the performance of the pupils and to analyze the near-field as well as the far-field response. Our EM analysis confirms that at 20 GHz the width of the central lobe in the far-field generated by a TP significantly decreases compared to a clear circular aperture with the same diameter.

  4. Tourette Syndrome: Complementary Insights from Measures of Cognitive Control, Eyeblink Rate, and Pupil Diameter

    Science.gov (United States)

    Tharp, Jordan A.; Wendelken, Carter; Mathews, Carol A.; Marco, Elysa J.; Schreier, Herbert; Bunge, Silvia A.

    2015-01-01

    Some individuals with Tourette syndrome (TS) have severe motoric and vocal tics that interfere with all aspects of their lives, while others have mild tics that pose few problems. We hypothesize that observed tic severity reflects a combination of factors, including the degree to which dopaminergic (DA) and/or noradrenergic (NE) neurotransmitter systems have been affected by the disorder, and the degree to which the child can exert cognitive control to suppress unwanted tics. To explore these hypotheses, we collected behavioral and eyetracking data from 26 patients with TS and 26 controls between ages 7 and 14, both at rest and while they performed a test of cognitive control. To our knowledge, this is the first study to use eyetracking measures in patients with TS. We measured spontaneous eyeblink rate as well as pupil diameter, which have been linked, respectively, to DA and NE levels in the central nervous system. Here, we report a number of key findings that held when we restricted analyses to unmedicated patients. First, patients’ accuracy on our test of cognitive control accounted for fully 50% of the variance in parentally reported tic severity. Second, patients exhibited elevated spontaneous eyeblink rates compared to controls, both during task performance and at rest, consistent with heightened DA transmission. Third, although neither task-evoked pupil dilation nor resting pupil diameter differed between TS patients and controls, pupil diameter was positively related to parentally reported anxiety levels in patients, suggesting heightened NE transmission in patients with comorbid anxiety. Thus, with the behavioral and eyetracking data gathered from a single task, we can gather objective data that are related both to tic severity and anxiety levels in pediatric patients with TS, and that likely reflect patients’ underlying neurochemical disturbances. PMID:26175694

  5. Size matter!

    DEFF Research Database (Denmark)

    Hansen, Pelle Guldborg; Jespersen, Andreas Maaløe; Skov, Laurits Rhoden

    2015-01-01

    Objectives We examined how a reduction in plate size would affect the amount of food waste from leftovers in a field experiment at a standing lunch for 220 CEOs. Methods A standing lunch for 220 CEOs in the Danish Opera House was arranged to feature two identical buffets with plates of two differ...

  6. The Binding Ring Illusion: assimilation affects the perceived size of a circular array [v2; ref status: indexed, http://f1000r.es/12q

    Directory of Open Access Journals (Sweden)

    J Daniel McCarthy

    2013-04-01

    Full Text Available Our perception of an object’s size arises from the integration of multiple sources of visual information including retinal size, perceived distance and its size relative to other objects in the visual field. This constructive process is revealed through a number of classic size illusions such as the Delboeuf Illusion, the Ebbinghaus Illusion and others illustrating size constancy. Here we present a novel variant of the Delbouef and Ebbinghaus size illusions that we have named the Binding Ring Illusion. The illusion is such that the perceived size of a circular array of elements is underestimated when superimposed by a circular contour – a binding ring – and overestimated when the binding ring slightly exceeds the overall size of the array. Here we characterize the stimulus conditions that lead to the illusion, and the perceptual principles that underlie it. Our findings indicate that the perceived size of an array is susceptible to the assimilation of an explicitly defined superimposed contour. Our results also indicate that the assimilation process takes place at a relatively high level in the visual processing stream, after different spatial frequencies have been integrated and global shape has been constructed. We hypothesize that the Binding Ring Illusion arises due to the fact that the size of an array of elements is not explicitly defined and therefore can be influenced (through a process of assimilation by the presence of a superimposed object that does have an explicit size.

  7. Learning a musical instrument: The influence of interpersonal interaction on outcomes for school-aged pupils

    OpenAIRE

    Creech, A.; Hallam, S.

    2011-01-01

    Researchers in recent years have increasingly placed an emphasis on seeking pupils' perceptions of educational settings. Alongside this shift towards attaching value to the pupil viewpoint has been a growing interest concerning how interpersonal relationships, manifested as control or responsiveness between teachers and pupils or parents and pupils, impact on learning processes and outcomes. This study aimed first to elicit pupils' perceptions of their interpersonal interactions with teachers...

  8. Building positive nature awareness in pupils using the "Rainforest of the Austrians" in Costa Rica.

    Science.gov (United States)

    Aubrecht, Margit; Hölzl, Irmgard; Huber, Werner; Weissenhofer, Anton

    2013-04-01

    . RICANCIE's primary objective is the defense of the Kichwa territory against encroaching mining and oil companies. During computer lessons pupils drew brilliant rainforest cards using graphic software, and in handicraft lessons they engraved rainforest animals on wooden plates. These pieces of art were sold at the "open school day". For presenting the project to other pupils at the secondary school Hellmonsödt, a rainforest quiz contest was prepared. The winners' prize was a tropical fruit tasting. Another presentation was done at the Biology Center in Linz with research expert Dr. Huber in the audience. The culmination was reached by handing over the sales profit to Michael Schnitzler in order to purchase rainforest land the size of a football field. Compared to other teaching methods this interdisciplinary approach perfectly involved and motivated pupils. The resulting presentations proved very important, because the pupils wanted to assure other teenagers that individuals have opportunities to influence the fate of our world. The educationally sustainable nature of the project becomes apparent years later, when the pupils involved have left school, but still talk about the progress of the "Rainforest of the Austrians" in Costa Rica.

  9. A Binary Shaped Mask Coronagraph for a Segmented Pupil

    CERN Document Server

    Enya, K

    2011-01-01

    We present the concept of a binary shaped mask coronagraph applicable to a telescope pupil including obscuration, based on previous works on binary shaped pupil mask by \\citet{Kasdin2005} and \\citet{Vanderbei1999}. Solutions with multi-barcode masks which "skip over" the obscuration are shown for various types of pupil of telescope, such as SUBARU, JWST, SPICA, and other examples. The number of diffraction tails in the point spread function of the coronagraphic image is reduced to two, thus offering a large discovery angle. The concept of mask rotation is also presented, which allows post-processing removal of diffraction tails and provides a 360$^{\\circ}$ continuous discovery angle. It is suggested that the presented concept offers solutions which potentially allow large telescopes with segmented pupil in future to be used as platforms for an coronagraph.

  10. Model of excellent kindergarten learning for excellent pupils

    NARCIS (Netherlands)

    Dijkstra, Elma; Mooij, Ton; Kirschner, Paul A.

    2012-01-01

    Dijkstra, E. M., Mooij, T., & Kirschner, P. A. (2012, 9 November). Model of excellent kindergarten learning for excellent pupils. Poster presentation at the International ICO Fall School, Girona, Spain.

  11. Determinants of Excellent Kindergarten Learning of Excellent Pupils

    NARCIS (Netherlands)

    Dijkstra, Elma; Mooij, Ton; Kirschner, Paul A.

    2013-01-01

    Dijkstra, E. M., Mooij, T., & Kirschner, P. A. (2013, 27 August). Determinants of Excellent Kindergarten Learning of Excellent Pupils. In J. Kornmann (Chair), Cognitive Abilities and Instructional Designs. Symposium conducted at the EARLI 2013 conference, Munich, Germany.

  12. Model of Excellent Kindergarten Learning for Excellent Pupils

    NARCIS (Netherlands)

    Dijkstra, Elma; Mooij, Ton; Kirschner, Paul A.

    2012-01-01

    Dijkstra, E. M., Mooij, T., & Kirschner, P. A. (2012, 11 October). Model of excellent kindergarten learning for excellent pupils. Poster presentation at the Teacher Expertise Symposium, University of Utrecht, Utrecht, The Netherlands.

  13. The Evolution of the Species: Pupil Perspectives and School Perspectives.

    Science.gov (United States)

    Hallden, Ola

    1988-01-01

    Investigates how 11th graders think with respect to evolution and the development of species. Reports that the pupils have extensive factual knowledge, but have difficulty in relating these facts in coherent descriptions and explanations. (Author/YP)

  14. Differences in the Value Orientation of Czech and Slovak Pupils

    Directory of Open Access Journals (Sweden)

    Vomáčková Helena

    2015-12-01

    Full Text Available This contribution brings a selection from the results of a research carried out during the years 2013 and 2014 among Czech and Slovak pupils of middle school age (i.e. 4th to 6th forms of primary schools. This study focused on monitoring and evaluating the differences and similarities in the value-oriented responses of pupils, according to the criteria of their nationality and sex. The pupils were expressing their opinions by means of a questionnaire survey with respect to selected situations on a four-degree scale and they further stated their vision of the world and their position in it. This contribution analyses statistically significant deviations which were found out among the positions held by Czech and Slovak boys and girls. The contribution also gives rise to a number of questions concerning the shift in values among the population of pupils of the formerly unified state.

  15. Effects of Bilingual Teaching Strategy on Pupils' Achievement in ...

    African Journals Online (AJOL)

    Open Access DOWNLOAD FULL TEXT ... The mode of instruction used by teachers of Mathematics (being a core subject) ... utilize bilingual approach to support teaching of Mathematics in primary schools to enhance pupils' performance.

  16. Pupil response and the subliminal mere exposure effect.

    Directory of Open Access Journals (Sweden)

    Sanae Yoshimoto

    Full Text Available The subliminal mere exposure effect (SMEE is the phenomenon wherein people tend to prefer patterns they have repeatedly observed without consciously identifying them. One popular explanation for the SMEE is that perceptual fluency within exposed patterns is misattributed to a feeling of preference for those patterns. Assuming that perceptual fluency is negatively correlated with the amount of mental effort needed to analyze perceptual aspects of incoming stimuli, pupil diameter should associate with SMEE strength since the former is known to reflect mental effort. To examine this hypothesis, we measured participants' pupil diameter during exposure to subthreshold stimuli. Following exposure, a preference test was administered. Average pupil diameter throughout exposure was smaller when the SMEE was induced than when the SMEE was not induced. This supports the hypothesis that increasing perceptual fluency during mere exposure modulates autonomic nervous responses, such as pupil diameter, and eventually leads to preference.

  17. PECULIARITIES OF GRAMMAR STUDY OF MOUNTAIN FIRST-FORM PUPILS

    Directory of Open Access Journals (Sweden)

    Marija Kiryk

    2015-04-01

    Full Text Available The articles describes the role of analiztor system (auditory, visual, kinesthetic at the initial stage of learning literacy and language development six years old. They from specific integration system, that provides more efficient perception, memorization and reproduction of educational material. The article deals with attempt to ascertain linguadidactic interconnections and interdependence between grammar education (reading, writing and speech of six-year pupils. Summing up it should be mentioned to organize 6-year pupils studing in the country mountain school becides pedagogical, economical, geographic and social problems psychologic linguadidactic are added. Preferences of mountain country children: –                    Formation from childhood ability to live in harmony with nature; –                    Sensitive  perception of alive and inanimate surrounding nature; –                    Life-style form children’s responsibility for entrusted things, labour habits, training by hard nature conditions. They should be solved in complex providing achievents of psychology, pedagogics, linguists and up-to-date technology. The aim of the article  - to reveal individual peculiarities of country mountain child who needs special method of approach to grammar studing as well as to help country teacher who strongly feels lack for efficient method help. All these affect on prepearing level, children’s outlook, general development. Scientific and methodogical institutions have not easy task-system training and skill raising of primary school teachers to realize State standart of primary general education. Acquaintance of country teacher with up-to-date achievements in psychologic, pedagogic and linguistic education will help him to organize his work in the country school on rather higher level as well as let him give more qualitative education services and save country school as the

  18. Teacher-Pupil Relationships: Black Students' Perceptions of Actual and Ideal Teacher/Pupil Control Behavior and Attitudes Toward Teachers and School

    Science.gov (United States)

    Sweeting, Lurlene M.; And Others

    1978-01-01

    Regardless of the direction of pupils' preferences (humanistic or custodial) the more closely pupils' perceptions of their teachers' actual behavior approximated their conception of ideal teacher behavior, the more positive were their attitudes toward teacher and school. (Author)

  19. Tonic Pupil Following Pars Plana Vitrectomy and Endolaser

    Directory of Open Access Journals (Sweden)

    Benyamin Ebrahim

    2009-01-01

    Full Text Available Tonic pupil was observed in a 67 year-old patient following a retinal detachment repair with pars plana vitrectomy, endolaser and silicone oil tamponade performed under retrobulbar anesthesia. The probable location of disturbance is the postganglionic parasympathetic fibers in the short ciliary nerves along their course to the pupil in the suprachoroidal space. A likely explanation for this phenomenon is injury to short ciliary nerves by endolaser treatment.

  20. HOW HEARING IMPAIRED PUPILS COMPREHEND CONCEPTS OF LIVING NATURE?

    Directory of Open Access Journals (Sweden)

    Jasmina KARIКЈ

    2005-12-01

    Full Text Available This research represents a part of a broader research on forming and accepting concepts about living beings in the field of nature and society by hearing impaired pupils. Shown results relate to the comprehension of concepts on higher level acquired during two researches. The first research relates to examining comprehension of concepts by recognizing complete classifications and the other to examining comprehension of concepts by analyzing definitions in the same pupil sample.

  1. Independence of pupils and their attitude towards academic achievement factors

    OpenAIRE

    Šmuc, Katja

    2013-01-01

    This diploma work focuses on the pupils' opinion about independent learning and factors of learning achievement. I have not found the literature that is dealing with the pupils' point of view on these two particular topics. First, in the theoretical part, the role of assessment in primary school, its development and different views on assessment through time, are presented. The acknowledgement, that the learning achievement depends on many different factors, leads to their presentation and ...

  2. Unilateral anterior ischemic optic neuropathy: chromatic pupillometry in affected, fellow non-affected and healthy control eyes

    Directory of Open Access Journals (Sweden)

    Kristina eHerbst

    2013-05-01

    Full Text Available The intrinsically photosensitive retinal ganglion cells (ipRGCs express the photopigment melanopsin, which is sensitive to blue light. Previous chromatic pupillometry studies have shown that the post-illumination response is considered an indicator of the melanopsin activation. The aim of this study was to investigate the ipRGC mediated pupil response in patients with a unilateral non-arteritic anterior ischemic optic neuropathy (NAION. Consensual pupil responses during and after exposure to continuous 20 s blue (470 nm or red (660 nm light of high intensity (300 cd/m2 were recorded in each eye for 10 patients. Comparisons were performed both intra-individually (affected versus non-affected eyes and inter-individually (compared with healthy controls. The pupil response was calculated both during the illumination and during the post-illumination phase. The pupil responses to blue and red colours were significantly reduced in the NAION-affected eyes, compared with the fellow non-affected eyes. When comparing the affected eyes with the healthy control eyes, the post-illumination responses were not significantly different. In addition, the post-illumination pupil responses after blue light exposure were increased in the fellow non-affected patients’ eyes, compared with the healthy controls. However, significance was only reached for the late post-illumination response. In conclusion, chromatic pupillometry disclosed reduced post-illumination pupil responses in the NAION-affected eyes, compared with the non-affected fellow eyes, suggesting dysfunction of the ipRGCs. Compared with the responses of the healthy controls, the blue light post-illumination pupil responses were similar in the affected eyes and increased in the fellow non-affected eyes. This suggests a possible adaptive phenomenon, involving the ipRGCs of both eyes after unilateral NAION.

  3. Pupil response as a predictor of blindsight in hemianopia.

    Science.gov (United States)

    Sahraie, Arash; Trevethan, Ceri T; MacLeod, Mary Joan; Urquhart, James; Weiskrantz, Lawrence

    2013-11-05

    Significantly above-chance detection of stimuli presented within the field defect of patients with postgeniculate lesions is termed "blindsight." It has been proposed that those with blindsight are more likely to benefit from visual rehabilitation by repeated stimulation, leading to increased visual sensitivity within their field defect. Establishing the incidence of blindsight and developing an objective and reliable method for its detection are of great interest. Sudden onsets of a grating pattern in the absence of any change in light flux result in a transient constriction of the pupil, termed "pupil grating response." The existence of pupil grating responses for stimuli presented within the blindfield has previously been reported in a hemianopic patient and two monkeys with removal of the primary visual cortex unilaterally. Here, we have systematically investigated the presence of a spatial channel of processing at a range of spatial frequencies using a psychophysical forced-choice technique and obtained the corresponding pupil responses in the blindfield of 19 hemianopic patients. In addition, in 13 cases we determined the pupil responses in a sighted field location that matched the blindfield eccentricities. Our findings demonstrate that blindfield pupil responses are similar to those for the sighted field, but attenuated in amplitude. Pupillometry correctly characterized the presence or absence of a significant psychophysical response and thus is worth measuring in the cortically blindfields as a predictor of intact psychophysical capacity. The incidence of blindsight where detection performance had been investigated psychophysically over a range of spatial frequencies was 70%.

  4. Year four pupils' understanding of division of whole numbers

    Science.gov (United States)

    Ibrahim, Faridah Mohamed; Pa, Nik Azis Nik

    2014-07-01

    Based on the theory of radical constructivism, this study investigated Year Four pupils' understandings of division by identifying their schemes of the division of whole numbers and how they used them in solving related problematic situations. Data incorporating both verbal and non-verbal behaviors were gathered from seven pupils based on the five clinical interview sessions involving imagining division, representing division, describing process and product of division, interpreting division statement, and solving division problem tasks. Four schemes that were identified are partitioning scheme, measuring scheme, repeated subtraction scheme, and inverse of multiplication scheme. Findings revealed that the measuring scheme was the dominant scheme for the division of whole numbers and the pupils only used the repeated and the inverse of multiplication schemes when they were asked to relate the subtraction or multiplication process with the division process. Further, the pupils were observed to use the long division algorithm in some situations, but there were indications that they used them with little understandings. It is suggested that more remains to be learnt about the nature of pupils' understanding of the division of whole numbers and how schemes of the division of whole numbers are formed and modified. Also, in order to provide appropriate guidance, mathematics teachers need to have some knowledge about pupils' available schemes of the division of whole numbers, no matter how primitive they might seem to the teachers.

  5. Are teachers' judgements of pupils' ability influenced by body shape?

    Science.gov (United States)

    Shackleton, N L; Campbell, T

    2014-04-01

    Evidence indicates that teachers can judge pupils on the basis of their physical appearance, including their body shape. Teacher bias towards obese pupils has been suggested as a potential pathway through which obese children attain relatively lower academic levels. The aim of this study was to investigate whether teachers' judgements of pupils' ability are influenced by the body shape of the child. The sample includes English, singleton children in state schools from the Millennium Cohort Study. The data were taken from the fourth wave of data collection, when the children were approximately 7 years old. In all, 5086/5072 children had teacher ability ratings of reading and maths. Logistic regression analyses were used to test whether teachers' perceptions of the child's reading and mathematics ability were influenced by the pupil's waist circumference, conditional upon cognitive test scores of reading and maths ability. After adjustment for cognitive test scores, no significant overall relationship was found between the pupil's waist circumference and the teacher's judgements of ability. No statistically significant differences were observed in the probability of being judged as above average after further adjustments were made for potential confounders. There is little evidence that teachers' judgements of pupils' ability are influenced by obesity.

  6. Impact of the size of the class on pupils’ psychosocial well-being

    DEFF Research Database (Denmark)

    Nielsen, B.B.; Kalvåg, H.; Pons, Francisco

    2006-01-01

    Most research on class size effect focuses on pupils’ school achievement but few on pupils’ psychosocial well-being. On the other hand an increasing number of studies have showed that there is a link between pupils’ psychosocial well-being and their school achievement. 97 Danish typically...... developing 3rd grade pupils were tested. They were divided into 3 class size groups: Small (10 pupils), Medium (20 pupils), and Large (25 pupils). The average age (10 years) and the proportion of boys and girls (50%) and SES (medium) were similar in the 3 class size groups. Pupils’ psychosocial well......-being was assessed with the Beck Youth Inventories of Emotional and Social Impairment, the Test of Emotion Comprehension, the Me and the School questionnaire, and The Pupil’s Self-report. Preliminary analyses showed that increasing class size had a significant increasing impact on pupils’ disruptive behaviours...

  7. Evidence for small scale variation in the vertebrate brain: mating strategy and sex affect brain size and structure in wild brown trout (Salmo trutta).

    Science.gov (United States)

    Kolm, N; Gonzalez-Voyer, A; Brelin, D; Winberg, S

    2009-12-01

    The basis for our knowledge of brain evolution in vertebrates rests heavily on empirical evidence from comparative studies at the species level. However, little is still known about the natural levels of variation and the evolutionary causes of differences in brain size and brain structure within-species, even though selection at this level is an important initial generator of macroevolutionary patterns across species. Here, we examine how early life-history decisions and sex are related to brain size and brain structure in wild populations using the existing natural variation in mating strategies among wild brown trout (Salmo trutta). By comparing the brains of precocious fish that remain in the river and sexually mature at a small size with those of migratory fish that migrate to the sea and sexually mature at a much larger size, we show, for the first time in any vertebrate, strong differences in relative brain size and brain structure across mating strategies. Precocious fish have larger brain size (when controlling for body size) but migratory fish have a larger cerebellum, the structure in charge of motor coordination. Moreover, we demonstrate sex-specific differences in brain structure as female precocious fish have a larger brain than male precocious fish while males of both strategies have a larger telencephalon, the cognitive control centre, than females. The differences in brain size and structure across mating strategies and sexes thus suggest the possibility for fine scale adaptive evolution of the vertebrate brain in relation to different life histories.

  8. Born Pupils? Natural Pedagogy and Cultural Pedagogy.

    Science.gov (United States)

    Heyes, Cecilia

    2016-03-01

    The theory of natural pedagogy is an important focus of research on the evolution and development of cultural learning. It proposes that we are born pupils; that human children genetically inherit a package of psychological adaptations that make them receptive to teaching. In this article, I first examine the components of the package-eye contact, contingencies, infant-directed speech, gaze cuing, and rational imitation-asking in each case whether current evidence indicates that the component is a reliable feature of infant behavior and a genetic adaptation for teaching. I then discuss three fundamental insights embodied in the theory: Imitation is not enough for cumulative cultural inheritance, the extra comes from blind trust, and tweaking is a powerful source of cognitive change. Combining the results of the empirical review with these insights, I argue that human receptivity to teaching is founded on nonspecific genetic adaptations for social bonding and social learning and acquires its species- and functionally specific features through the operation of domain-general processes of learning in sociocultural contexts. We engage, not in natural pedagogy, but in cultural pedagogy.

  9. Shaped pupil design for future space telescopes

    Science.gov (United States)

    Riggs, A. J. Eldorado; Zimmerman, Neil; Carlotti, Alexis; Kasdin, N. Jeremy; Vanderbei, Robert

    2014-08-01

    Several years ago at Princeton we invented a technique to optimize shaped pupil (SP) coronagraphs for any telescope aperture. In the last year, our colleagues at the Jet Propulsion Laboratory (JPL) invented a method to produce these non-freestanding mask designs on a substrate. These two advances allowed us to design SPs for two possible space telescopes for the direct imaging of exoplanets and disks, WFIRST-AFTA and Exo-C. In December 2013, the SP was selected along with the hybrid Lyot coronagraph for placement in the AFTA coronagraph instrument. Here we describe our designs and analysis of the SPs being manufactured and tested in the High Contrast Imaging Testbed at JPL.We also explore hybrid SP coronagraph designs for AFTA that would improve performance with minimal or no changes to the optical layout. These possibilities include utilizing a Lyot stop after the focal plane mask or applying large, static deformations to the deformable mirrors (nominally for wavefront correction) already in the system.

  10. Safety Evaluation of Highway Tunnel-Entrance Illuminance Transition Based on Eye-Pupil Changes

    Directory of Open Access Journals (Sweden)

    Zhigang Du

    2014-10-01

    Full Text Available Utilizing the EMR-8B eye-tracker system, the pupil changes of eight drivers were monitored when they drove through 26 typical highway tunnels. Based on the test results, the driver’s pupil areas and pupil illuminance were found to be in a power function relationship at tunnel entrances. Furthermore, a quantitative relationship between the pupil area and its critical velocity was established, and the ratio of pupil area’s velocity in relation to its critical velocity was used to evaluate the lighting transitions and to establish the ideal curve of pupil illuminance at tunnel entrances. The results demonstrated that the relationship between the pupil illuminance of the tunnel entrance and the driver’s pupil areas conforms to the Stevens law found in experimental psychology; severe pupil illuminance transition within the range of 10 metres of the existing highway tunnel entrances, which results in great visual load, is in urgent need of improvement.

  11. Annular pupil filter under shot-noise condition for linear and non linear microscopy.

    Science.gov (United States)

    Ronzitti, Emiliano; Vicidomini, Giuseppe; Caorsi, Valentina; Diaspro, Alberto

    2009-04-13

    The imaging performances of multiphoton excitation and confocal laser scanning microscopy are herby considered: in typical experimental imaging conditions, a small finite amount of photon reaches the detector giving shot-noise fluctuations which affects the signal acquired. A significant detriment in the high frequencies transmission capability is obtained. In order to partially recover the high frequencies information lost, the insertion of a pupil plane filter in the microscope illumination light pathway on the objective lens is proposed. We demonstrate high-frequency and resolution enhancement in the case of linear and non linear fluorescence microscope approach under shot-noise condition.

  12. Challenges and solutions in the calibration of projection lens pupil-image metrology tools

    Science.gov (United States)

    Slonaker, Steve; Riffel, Bryan; Nishinaga, Hisashi

    2009-03-01

    As imaging requirements and limits continue to be pushed tighter and lower, it has become imperative that accurate and repeatable measurement of the projection lens (PL) pupil be readily available. These are important for setup and adjustment of the illumination distribution, measurement and optimization of the lens aberrations, and verification of lens NA and transmission. Accurate testing of these items is critical during initial installation and setup of a photolithography tool, but it continues to prove useful each time any projection lens pupil-image measurement is made. The basic raw data from any such measurement is in the form of a pixelized 'image' captured by a projection lens pupil microscope. Such images have typically been referred to as pupilgrams1, and many prior works have reported on their application and analysis1,2,3. Each of these measurements can be affected by errors in the measurement tool used. The error modes can be broadly divided into two distinct groups: uncompensated transmission loss, and uncompensated distortion (or remapping) error. For instance, in illuminator measurements, the first will yield intensity error and the second will yield image shape mapping error. These errors may or may not lie exclusively in the optics of the measurement tool. But, regardless of their source, they will propagate through the analysis of the pupilgram images. For this reason, at minimum they must be measured and judged for relative impact, if only to confirm that the errors do not change the conclusions or results. In this paper, we will discuss and present methods for measuring the image distortion present in a PL pupil-image microscope. These data are used to build a 'map' of errors vs. position in the lens pupil. The maps then serve as the basis for image-processing-based compensation that can be applied to all subsequent microscope images. A novel vitally important feature of the technique presented is that it calibrates the distortion of the

  13. Apodized pupil Lyot coronagraphs for arbitrary apertures. V. Hybrid Shaped Pupil designs for imaging Earth-like planets with future space observatories

    CERN Document Server

    N'Diaye, Mamadou; Pueyo, Laurent; Carlotti, Alexis; Stark, Christopher C; Perrin, Marshall D

    2016-01-01

    We introduce a new class of solutions for Apodized Pupil Lyot Coronagraphs (APLC) with segmented aperture telescopes to remove broadband diffracted light from a star with a contrast level of $10^{10}$. These new coronagraphs provide a key advance to enabling direct imaging and spectroscopy of Earth twins with future large space missions. Building on shaped pupil (SP) apodization optimizations, our approach enables two-dimensional optimizations of the system to address any aperture features such as central obstruction, support structures or segment gaps. We illustrate the technique with a design that could reach $10^{10}$ contrast level at 34\\,mas for a 12\\,m segmented telescope over a 10\\% bandpass centered at a wavelength $\\lambda_0=$500\\,nm. These designs can be optimized specifically for the presence of a resolved star, and in our example, for stellar angular size up to 1.1\\,mas. This would allow probing the vicinity of Sun-like stars located beyond 4.4\\,pc, therefore fully retiring this concern. If the fr...

  14. Experimental demonstration of binary shaped pupil mask coronagraphs for telescopes with obscured pupils

    CERN Document Server

    Haze, Kanae; Abe, Lyu; Takahashi, Aoi; Kotani, Takayuki; Yamamuro, Tomoyasu

    2016-01-01

    We present the fabrication and experimental demonstration of three free-standing binary shaped pupil mask coronagraphs, which are applicable for telescopes with partially obscured pupils. Three masks, designed to be complementary (labeled Mask-A, Mask-B, and Mask-C), were formed in 5 micron thick nickel. The design of Mask-A is based on a one-dimensional barcode mask. The design principle of Mask-B is similar, but has a smaller inner working angle and a lower contrast than Mask-A. Mask-C is based on a concentric ring mask and provides the widest dark region and a symmetric point spread function. Mask-A and Mask-C were both designed to produce a flexibly tailored dark region (i.e., non-uniform contrast). The contrast was evaluated using a light source comprising a broadband super-luminescent light-emitting diode with a center wavelength of 650 nm, and the measurements were carried out in a large vacuum chamber. Active wavefront control was not applied in this work. The coronagraphic images obtained by experime...

  15. Internet usage of fourth-grader primary school pupils

    Directory of Open Access Journals (Sweden)

    Peter Kristof Nagy

    2014-08-01

    Full Text Available The development of information and communication technologies has resulted in revolutionary changes, which seem to continue in economy, society and many areas of life. The most important resource of the new social structure emerging as a result of technologies is information, thus the development of human capacity related to the use of information is extremely important. It may not be easy for parents and teachers to face the fact that the majority of their children/pupils know more about cyberspace than themselves. But are primary school pupils really better versed? Does digital literacy indeed automatically evolve? Does the use of the internet by all means improve children’s academic performance? In our current study we are researching how primary school pupils in the easternmost part of Hungary use the internet, and what effects it has on their studies. We would also like to emphasize the role of teachers working at the lower grades of the primary school in the formation of pupils’ digital literacy. In 2013 190 fourth-grader primary school pupils of eight schools filled in our questionnaire. Based on the data negative correlation was found between the time spent on web browsing and the academic average. Analysis of variance also revealed that those pupils have a higher academic average whose parents regularly check the purpose of their children’s internet usage. Our research results showed that the pupils who use the internet and the library equally to search for new information have a higher academic average compared to those pupils who only make use of either the traditional or the online option only. The most important result of the research is that in the case of adequate parental or professional (teacher control internet may have fruitful effects on pupils’ studies, but in the lack of such control the opposite is more likely.

  16. How do Organizational Learning and Market Conditions Affect the Relationship between Entrepreneurial Orientation and Firm Growth? A Preliminary Analysis on Small and Medium Size Hotels in Peninsular Malaysia

    National Research Council Canada - National Science Library

    Azilah Kasim; Levent Altinay

    2016-01-01

      This is a preliminary analysis on the influence of organizational learning and market conditions on the relationships between entrepreneurial orientation and growth of small and medium size hotels...

  17. Phase and Pupil Amplitude Recovery for JWST Space-Optics Control

    Science.gov (United States)

    Dean, B. H.; Zielinski, T. P.; Smith, J. S.; Bolcar, M. R.; Aronstein, D. L.; Fienup, J. R.

    2010-01-01

    This slide presentation reviews the phase and pupil amplitude recovery for the James Webb Space Telescope (JWST) Near Infrared Camera (NIRCam). It includes views of the Integrated Science Instrument Module (ISIM), the NIRCam, examples of Phase Retrieval Data, Ghost Irradiance, Pupil Amplitude Estimation, Amplitude Retrieval, Initial Plate Scale Estimation using the Modulation Transfer Function (MTF), Pupil Amplitude Estimation vs lambda, Pupil Amplitude Estimation vs. number of Images, Pupil Amplitude Estimation vs Rotation (clocking), and Typical Phase Retrieval Results Also included is information about the phase retrieval approach, Non-Linear Optimization (NLO) Optimized Diversity Functions, and Least Square Error vs. Starting Pupil Amplitude.

  18. Genotype and fetal size affect maternal-fetal amino acid status and fetal endocrinology in Large White × Landrace and Meishan pigs.

    Science.gov (United States)

    Ashworth, Cheryl J; Nwagwu, Margaret O; McArdle, Harry J

    2013-01-01

    This study compared maternal plasma amino acid concentrations, placental protein secretion in vitro and fetal body composition and plasma amino acid and hormone concentrations in feto-placental units from the smallest and a normally-sized fetus carried by Large White × Landrace or Meishan gilts on Day 100 of pregnancy. Compared with Large White × Landrace, Meishan placental tissue secreted more protein and Meishan fetuses contained relatively more fat and protein, but less moisture. Fetal plasma concentrations of insulin, triiodothryonine, thyroxine and insulin-like growth factor (IGF)-II were higher in Meishan than Large White × Landrace fetuses. In both breeds, fetal cortisol concentrations were inversely related to fetal size, whereas concentrations of IGF-I were higher in average-sized fetuses. Concentrations of 10 amino acids were higher in Large White × Landrace than Meishan gilts, while glutamine concentrations were higher in Meishan gilts. Concentrations of alanine, aspartic acid, glutamic acid and threonine were higher in Meishan than Large White × Landrace fetuses. Average-sized fetuses had higher concentrations of asparagine, leucine, lysine, phenylalanine, threonine, tyrosine and valine than the smallest fetus. This study revealed novel genotype and fetal size differences in porcine maternal-fetal amino acid status and fetal hormone and metabolite concentrations.

  19. Pupil diameter covaries with BOLD activity in human locus coeruleus.

    Science.gov (United States)

    Murphy, Peter R; O'Connell, Redmond G; O'Sullivan, Michael; Robertson, Ian H; Balsters, Joshua H

    2014-08-01

    The locus coeruleus-noradrenergic (LC-NA) neuromodulatory system has been implicated in a broad array of cognitive processes, yet scope for investigating this system's function in humans is currently limited by an absence of reliable non-invasive measures of LC activity. Although pupil diameter has been employed as a proxy measure of LC activity in numerous studies, empirical evidence for a relationship between the two is lacking. In the present study, we sought to rigorously probe the relationship between pupil diameter and BOLD activity localized to the human LC. Simultaneous pupillometry and fMRI revealed a relationship between continuous pupil diameter and BOLD activity in a dorsal pontine cluster overlapping with the LC, as localized via neuromelanin-sensitive structural imaging and an LC atlas. This relationship was present both at rest and during performance of a two-stimulus oddball task, with and without spatial smoothing of the fMRI data, and survived retrospective image correction for physiological noise. Furthermore, the spatial extent of this pupil/LC relationship guided a volume-of-interest analysis in which we provide the first demonstration in humans of a fundamental characteristic of animal LC activity: phasic modulation by oddball stimulus relevance. Taken together, these findings highlight the potential for utilizing pupil diameter to achieve a more comprehensive understanding of the role of the LC-NA system in human cognition.

  20. Memory, emotion, and pupil diameter: Repetition of natural scenes.

    Science.gov (United States)

    Bradley, Margaret M; Lang, Peter J

    2015-09-01

    Recent studies have suggested that pupil diameter, like the "old-new" ERP, may be a measure of memory. Because the amplitude of the old-new ERP is enhanced for items encoded in the context of repetitions that are distributed (spaced), compared to massed (contiguous), we investigated whether pupil diameter is similarly sensitive to repetition. Emotional and neutral pictures of natural scenes were viewed once or repeated with massed (contiguous) or distributed (spaced) repetition during incidental free viewing and then tested on an explicit recognition test. Although an old-new difference in pupil diameter was found during successful recognition, pupil diameter was not enhanced for distributed, compared to massed, repetitions during either recognition or initial free viewing. Moreover, whereas a significant old-new difference was found for erotic scenes that had been seen only once during encoding, this difference was absent when erotic scenes were repeated. Taken together, the data suggest that pupil diameter is not a straightforward index of prior occurrence for natural scenes. © 2015 Society for Psychophysiological Research.

  1. Prenatal exposure to alcohol does not affect radial maze learning and hippocampal mossy fiber sizes in three inbred strains of mouse

    Directory of Open Access Journals (Sweden)

    Bertholet Jean-Yves

    2005-04-01

    Full Text Available Abstract Background The aim of this study was to investigate the effects of prenatal alcohol exposure on radial-maze learning and hippocampal neuroanatomy, particularly the sizes of the intra- and infrapyramidal mossy fiber (IIPMF terminal fields, in three inbred strains of mice (C57BL/6J, BALB/cJ, and DBA/2J. Results Although we anticipated a modification of both learning and IIPMF sizes, no such effects were detected. Prenatal alcohol exposure did, however, interfere with reproduction in C57BL/6J animals and decrease body and brain weight (in interaction with the genotype at adult age. Conclusion Prenatal alcohol exposure influenced neither radial maze performance nor the sizes of the IIPMF terminal fields. We believe that future research should be pointed either at different targets when using mouse models for Fetal Alcohol Syndrome (e.g. more complicated behavioral paradigms, different hippocampal substructures, or other brain structures or involve different animal models.

  2. Epidemiology of Head Lice Infestation in Primary SchoolPupils, in Khajeh City, East Azerbaijan Province, Iran

    Directory of Open Access Journals (Sweden)

    M Shayeghi

    2010-06-01

    Full Text Available Background: Pediculus capitis (Anoplura: Pediculidae or head louse is an obligate ectoparasite transmitted mainly through physical contact. This study was conducted to survey the prevalence of head lice infestation rate and some risk factors in Primary School pupils, in Khajeh City East Azerbaijan Province, IranMethods: We selected 20 primary schools of Khajeh City during 2008 and 2009. Totally 500 pupils including 200 boys and 300 girls from all grade 1-5 were selected by multistage, systematic random sampling in rural areas of Khajeh City and were examined for lice. In addition, a standard questionnaire recorded information about demographic features of each pupil. Results were analyzed by SPSS software.Results: The total prevalence of head lice infestation in this study was 4.8%. and the prevalence rate was significantly higher in girls (6.66% than in boys (2%. Epidemiological factors such as: sex, school grade, family size, parent's education, type of house, hair washing (per week, number of using comb per day, were evaluated and results showed significant difference in head lice infestation and sex, school grade ,family size ,father education ,and type of house (P< 0.05.Conclusion: Pediculosis is a public health problem in many parts of the world, and due to the higher prevalence of pediculosis in crowded families, family by lower levels of father's education and socioeconomic status in our study and rural area, it is necessary to give health education for families to prevent of pediculosis in this area.

  3. Nano-size scaling of alloy intra-particle vs. inter-particle separation transitions: prediction of distinctly interface-affected critical behaviour.

    Science.gov (United States)

    Polak, M; Rubinovich, L

    2016-07-21

    Phase-separation second-order transitions in binary alloy particles consisting of ∼1000 up to ∼70 000 atoms (∼1-10 nm) are modeled focusing on the unexplored issue of finite-size scaling in such systems, particularly on evaluation of correlation-length critical exponents. Our statistical-thermodynamic approach is based on mean-field analytical expression for the Ising model free energy that facilitates highly efficient computations furnishing comprehensive data for fcc rectangular nanoparticles (NPs). These are summed up in intra- and inter-particle scaling plots as well as in nanophase separation diagrams. Temperature-induced variations in the interface thickness in Janus-type intra-particle configurations and NP size-dependent shifts in the critical temperature of their transition to solid-solution reflect power-law behavior with the same critical exponent, ν = 0.83. It is attributed to dominant interfacial effects that are absent in inter-particle transitions. Variations in ν with nano-size, as revealed by a refined analysis, are linearly extrapolated in order to bridge the gap to larger particles within and well beyond the nanoscale, ultimately yielding ν = 1.0. Besides these findings, the study indicates the key role of the surface-area to volume ratio as an effective linear size, revealing a universal, particle-shape independent, nanoscaling of the critical-temperature shifts.

  4. Optimization of Apodized Pupil Lyot Coronagraph for ELTs

    CERN Document Server

    Martínez, P; Kasper, M; Baudoz, P; Cavarroc, C

    2007-01-01

    We study the optimization of the Apodized Pupil Lyot Coronagraph (APLC) in the context of exoplanet imaging with ground-based telescopes. The APLC combines an apodization in the pupil plane with a small Lyot mask in the focal plane of the instrument. It has been intensively studied in the literature from a theoretical point of view, and prototypes are currently being manufactured for several projects. This analysis is focused on the case of Extremely Large Telescopes, but is also relevant for other telescope designs. We define a criterion to optimize the APLC with respect to telescope characteristics like central obscuration, pupil shape, low order segment aberrations and reflectivity as function of the APLC apodizer function and mask diameter. Specifically, the method was applied to two possible designs of the future European-Extremely Large Telescope (E-ELT). Optimum configurations of the APLC were derived for different telescope characteristics. We show that the optimum configuration is a stronger function...

  5. Pupil dilation patterns reflect the contents of consciousness.

    Science.gov (United States)

    Kang, Olivia; Wheatley, Thalia

    2015-09-01

    The study of human consciousness has historically depended on introspection. However, introspection is constrained by what can be remembered and verbalized. Here, we demonstrate the utility of high temporal resolution pupillometry to track the locus of conscious attention dynamically, over a single trial. While eye-tracked, participants heard several musical clips played diotically (same music in each ear) and, later, dichotically (two clips played simultaneously, one in each ear). During dichotic presentation, participants attended to only one ear. We found that the temporal pattern of pupil dilation dynamics over a single trial discriminated which piece of music was consciously attended on dichotic trials. Deconvolving these pupillary responses further revealed the real-time changes in stimulus salience motivating pupil dilation. Taken together, these results show that pupil dilation patterns during single-exposure to dynamic stimuli can be exploited to discern the contents of conscious attention.

  6. "Peace to Learn"-- A Discourse Analysis of Pupils' Perceptions

    Science.gov (United States)

    Paaso, E.; Uusiautti, S.; Maatta, K.

    2013-01-01

    Peace to learn refers to a peaceful state that makes meaningful and productive learning possible--in other words, the conditions that allow or hinder pupils to work peacefully in the classroom. How pupils perceive their

  7. LWIR pupil imaging and longer-term calibration stability

    Science.gov (United States)

    LeVan, Paul D.; Sakoglu, Ünal

    2016-09-01

    A previous paper described LWIR pupil imaging, and an improved understanding of the behavior of this type of sensor for which the high-sensitivity focal plane array (FPA) operated at higher flux levels includes a reversal in signal integration polarity. We have since considered a candidate methodology for efficient, long-term calibration stability that exploits the following two properties of pupil imaging: (1) a fixed pupil position on the FPA, and (2) signal levels from the scene imposed on significant but fixed LWIR background levels. These two properties serve to keep each pixel operating over a limited dynamic range that corresponds to its location in the pupil and to the signal levels generated at this location by the lower and upper calibration flux levels. Exploiting this property for which each pixel of the Pupil Imager operates over its limited dynamic range, the signal polarity reversal between low and high flux pixels, which occurs for a circular region of pixels near the upper edges of the pupil illumination profile, can be rectified to unipolar integration with a two-level non-uniformity correction (NUC). Images corrected real-time with standard non-uniformity correction (NUC) techniques, are still subject to longer-term drifts in pixel offsets between recalibrations. Long-term calibration stability might then be achieved using either a scene-based non-uniformity correction approach, or with periodic repointing for off-source background estimation and subtraction. Either approach requires dithering of the field of view, by sub-pixel amounts for the first method, or by large off-source motions outside the 0.38 milliradian FOV for the latter method. We report on the results of investigations along both these lines.

  8. The Frequency of Rapid Pupil Dilations as a Measure of Linguistic Processing Difficulty.

    Directory of Open Access Journals (Sweden)

    Vera Demberg

    Full Text Available While it has long been known that the pupil reacts to cognitive load, pupil size has received little attention in cognitive research because of its long latency and the difficulty of separating effects of cognitive load from the light reflex or effects due to eye movements. A novel measure, the Index of Cognitive Activity (ICA, relates cognitive effort to the frequency of small rapid dilations of the pupil. We report here on a total of seven experiments which test whether the ICA reliably indexes linguistically induced cognitive load: three experiments in reading (a manipulation of grammatical gender match/mismatch, an experiment of semantic fit, and an experiment comparing locally ambiguous subject versus object relative clauses, all in German, three dual-task experiments with simultaneous driving and spoken language comprehension (using the same manipulations as in the single-task reading experiments, and a visual world experiment comparing the processing of causal versus concessive discourse markers. These experiments are the first to investigate the effect and time course of the ICA in language processing. All of our experiments support the idea that the ICA indexes linguistic processing difficulty. The effects of our linguistic manipulations on the ICA are consistent for reading and auditory presentation. Furthermore, our experiments show that the ICA allows for usage within a multi-task paradigm. Its robustness with respect to eye movements means that it is a valid measure of processing difficulty for usage within the visual world paradigm, which will allow researchers to assess both visual attention and processing difficulty at the same time, using an eye-tracker. We argue that the ICA is indicative of activity in the locus caeruleus area of the brain stem, which has recently also been linked to P600 effects observed in psycholinguistic EEG experiments.

  9. THE LEVEL OF PUPILS KNOWLEDGE DEPENDING OF TEACHING PROGRAM

    Directory of Open Access Journals (Sweden)

    Maja Batez

    2011-09-01

    Full Text Available At the sample of 117 schoolgirls, 10 years old (+-6 monts, the experimental reserch had been applaid. The goal was to reserch the influence of two different teaching program to the level of pupils knowledge (motor skills. Differences of the level of knowledge were tested by multivariat analisis of variance, discrimniative analisis, as wel as the differences for every variable by univariat analisis of variance. It was concluded that there were the significant statistical difference in pupils knowledge depending of teaching program.

  10. The Perception of Overweight Pupils by the Group of Pupils during the Physical Education and Sports Class

    Directory of Open Access Journals (Sweden)

    Simona PETRACOVSCHI

    2012-12-01

    Full Text Available Overweight produces discrimination and marginalisation during the physical education and sports (P.E. class. The purpose of this research is to identify the way in which pupils with normal weight perceive their overweight peers, with the aim of identifying the problems of collaboration and co-participation within the teams and pairs established during P.E. classes. The semi-directive interview method was used; it was applied on a class of pupils aged 11 and 12 from a school in Timisoara. The interviews were processed using the thematic analysis and show the fact that pupils with normal weight avoid interacting with the overweight peers for fear of being identified with the latter.

  11. Inspiration or deflation? Feeling similar or dissimilar to slim and plus-size models affects self-evaluation of restrained eaters.

    Science.gov (United States)

    Papies, Esther K; Nicolaije, Kim A H

    2012-01-01

    The present studies examined the effect of perceiving images of slim and plus-size models on restrained eaters' self-evaluation. While previous research has found that such images can lead to either inspiration or deflation, we argue that these inconsistencies can be explained by differences in perceived similarity with the presented model. The results of two studies (ns=52 and 99) confirmed this and revealed that restrained eaters with high (low) perceived similarity to the model showed more positive (negative) self-evaluations when they viewed a slim model, compared to a plus-size model. In addition, Study 2 showed that inducing in participants a similarities mindset led to more positive self-evaluations after viewing a slim compared to a plus-size model, but only among restrained eaters with a relatively high BMI. These results are discussed in the context of research on social comparison processes and with regard to interventions for protection against the possible detrimental effects of media images.

  12. Colony size, but not density, affects survival and mating success of alternative male reproductive tactics in a polyphenic mite, Rhizoglyphus echinopus.

    Science.gov (United States)

    Radwan, Jacek; Lukasiewicz, Aleksandra; Twardawa, Mateusz

    2014-01-01

    Among acarid mites, a number of species are characterised by the presence of discontinuous morphologies (armed heteromorphs vs. unarmed homeomorphs) associated with alternative mating tactics (fighting vs. scramble competition). In Rhizoglyphus echinopus, expression of the fighter morph is suppressed, via pheromones, in large, dense colonies. If this mechanism is adaptive, fighters should have relatively lower fitness in large and/or dense colonies, due to costs incurred from fighting, which is often fatal. In order to test these predictions, we quantified the survival and mating success of fighters and scramblers in colonies of equal sex and morph ratios; these colonies either differed in size (4, 8, or 32 individuals) but not density or differed in density but not size (all consisted of 8 individuals). We found that the relative survival and mating success of fighters was inversely related to colony size, but we did not find a significant effect of colony density. The higher mating success of fighters in small colonies was due to the fact that, after killing rival males, these fighters were able to monopolise females. This situation was not found in larger colonies, in which there was a larger number of competitors and fighters suffered relatively higher mortality. These results indicate that morph determination, guided by social cues, allows for the adaptive adjustment of mating tactics to existing demographic conditions.

  13. {sup 18}F-FDG PET uptake in the pre-Huntington disease caudate affects the time-to-onset independently of CAG expansion size

    Energy Technology Data Exchange (ETDEWEB)

    Ciarmiello, Andrea; Giovacchini, Giampiero; Bruselli, Laura [Nuclear Medicine Department, S. Andrea Hospital, La Spezia (Italy); Orobello, Sara; Elifani, Francesca; Squitieri, Ferdinando [Centre for Neurogenetics and Rare Diseases, IRCCS Neuromed, Pozzilli, IS (Italy)

    2012-06-15

    To test in a longitudinal follow-up study whether basal glucose metabolism in subjects with a genetic risk of Huntington disease (HD) may influence the onset of manifest symptoms. The study group comprised 43 presymptomatic (preHD) subjects carrying the HD mutation. They underwent a {sup 18}F-FDG PET scan and were prospectively followed-up for at least 5 years using the unified HD rating scale to detect clinical changes. Multiple regression analysis included subject's age, CAG mutation size and glucose uptake as variables in a model to predict age at onset. Of the 43 preHD subjects who manifested motor symptoms, suggestive of HD, after 5 years from the PET scan, 26 showed a mean brain glucose uptake below the cut-off of 1.0493 in the caudate, significantly lower than the 17 preHD subjects who remained symptom-free (P < 0.0001). This difference was independent of mutation size. Measurement of brain glucose uptake improved the CAG repeat number and age-based model for predicting age at onset by 37 %. A reduced level of glucose metabolism in the brain caudate may represent a predisposing factor that contributes to the age at onset of HD in preHD subjects, in addition to the mutation size. (orig.)

  14. Adie’s Tonic Pupil in Systemic Sclerosis: A Rare Association

    Directory of Open Access Journals (Sweden)

    Anusha Venkataraman

    2015-01-01

    Full Text Available We report a rare association of Adie’s tonic pupil in a patient with systemic sclerosis who was otherwise systemically stable. This paper is an effort to unravel whether the tonic pupil and systemic sclerosis are an association by chance (which may be the case or systemic sclerosis is the source of the tonic pupil.

  15. Teacher Candidates Speak Out: Exploring Concerns Related to Pupil Learning and Efficacy When Learning to Teach

    Science.gov (United States)

    Derosier, Sharline; Soslau, Elizabeth

    2014-01-01

    Research shows that teachers' efficacy relates to pupil achievement. Strong efficacy, or a self-belief that one can positively impact pupil learning, is risked when teachers develop concerns related to pupil learning. This study explored the perceived concerns of teacher candidates (N = 3) throughout an eight-week clinical field experience.…

  16. Teacher Candidates Speak Out: Exploring Concerns Related to Pupil Learning and Efficacy When Learning to Teach

    Science.gov (United States)

    Derosier, Sharline; Soslau, Elizabeth

    2014-01-01

    Research shows that teachers' efficacy relates to pupil achievement. Strong efficacy, or a self-belief that one can positively impact pupil learning, is risked when teachers develop concerns related to pupil learning. This study explored the perceived concerns of teacher candidates (N = 3) throughout an eight-week clinical field experience.…

  17. The Attainment of Pupils in Gaelic-Medium Primary Education in Scotland

    Science.gov (United States)

    O'Hanlon, Fiona; Paterson, Lindsay; McLeod, Wilson

    2013-01-01

    The curricular attainment of pupils in Gaelic-medium primary education in Scotland is investigated using surveys of Gaelic-medium and English-medium pupils in the fifth and seventh years of primary school (approximately 9 and 11 years of age) in 2007. The Gaelic-medium survey was essentially a census of pupils. The English-medium survey was a…

  18. Consulting Pupils about Classroom Teaching and Learning: Policy, Practice and Response in One School

    Science.gov (United States)

    Morgan, Bethan

    2011-01-01

    This article reports on an ESRC (Economic and Social Research Council) doctoral study which investigated how teachers consulted pupils about teaching and learning in classrooms. Interest in consulting pupils has increased over the last decade; existing research suggests pupils have valuable perspectives on teaching and learning which teachers can…

  19. Are Polish Primary School Pupils in Favor of Wearing Uniforms? Snapshot Comment

    Science.gov (United States)

    Asotska, Julia; Butler, Norman L.; Davidson, Barry S.; Griffith, Kimberly Grantham; Brown, Veda E.; Kritsonis, Wiilliam Allan

    2007-01-01

    The purpose of this article is to discuss whether Polish primary school pupils want to wear uniforms, and it is motivated by the Polish government's recently proposed policy: Zero Tolerance for Violence at School. Seventy one pupils, who attend Podstawowka Nr30 school in Cracow, were surveyed, and the authors found that most pupils are not in…

  20. Tomorrow's Workforce: School Pupils' Views of a Career in Hospitality. Research Report.

    Science.gov (United States)

    Tregaskis, Olga; And Others

    A survey involving 1,024 secondary pupils and 22 career educators from schools throughout the United Kingdom collected information on pupils' perceptions of entering the hotel and catering industry as a career. The research looked in detail at the job expectations of pupils, the status they associated with hotel and catering and nonhotel and…