Velocity storage contribution to vestibular self-motion perception in healthy human subjects.

Science.gov (United States)

Bertolini, G; Ramat, S; Laurens, J; Bockisch, C J; Marti, S; Straumann, D; Palla, A

2011-01-01

Self-motion perception after a sudden stop from a sustained rotation in darkness lasts approximately as long as reflexive eye movements. We hypothesized that, after an angular velocity step, self-motion perception and reflexive eye movements are driven by the same vestibular pathways. In 16 healthy subjects (25-71 years of age), perceived rotational velocity (PRV) and the vestibulo-ocular reflex (rVOR) after sudden decelerations (90°/s(2)) from constant-velocity (90°/s) earth-vertical axis rotations were simultaneously measured (PRV reported by hand-lever turning; rVOR recorded by search coils). Subjects were upright (yaw) or 90° left-ear-down (pitch). After both yaw and pitch decelerations, PRV rose rapidly and showed a plateau before decaying. In contrast, slow-phase eye velocity (SPV) decayed immediately after the initial increase. SPV and PRV were fitted with the sum of two exponentials: one time constant accounting for the semicircular canal (SCC) dynamics and one time constant accounting for a central process, known as velocity storage mechanism (VSM). Parameters were constrained by requiring equal SCC time constant and VSM time constant for SPV and PRV. The gains weighting the two exponential functions were free to change. SPV were accurately fitted (variance-accounted-for: 0.85 ± 0.10) and PRV (variance-accounted-for: 0.86 ± 0.07), showing that SPV and PRV curve differences can be explained by a greater relative weight of VSM in PRV compared with SPV (twofold for yaw, threefold for pitch). These results support our hypothesis that self-motion perception after angular velocity steps is be driven by the same central vestibular processes as reflexive eye movements and that no additional mechanisms are required to explain the perceptual dynamics.

Perception of Individualism and Collectivism in Dutch Society: A Developmental Approach

Science.gov (United States)

Oppenheimer, Louis

2004-01-01

Within Triandis's (1994) theoretical framework, two studies are reported that deal with the developmental course for subjective perceptions of cultural dimensions in Dutch society (i.e., vertical and horizontal individualism and collectivism). While perceptions of society are always subjectively determined, the perceived dimensions that are…

Subjective Vertical Conflict Theory and Space Motion Sickness.

Science.gov (United States)

Chen, Wei; Chao, Jian-Gang; Wang, Jin-Kun; Chen, Xue-Wen; Tan, Cheng

2016-02-01

Space motion sickness (SMS) remains a troublesome problem during spaceflight. The subjective vertical (SV) conflict theory postulates that all motion sickness provoking situations are characterized by a condition in which the SV sensed from gravity and visual and idiotropic cues differs from the expected vertical. This theory has been successfully used to predict motion sickness in different vehicles on Earth. We have summarized the most outstanding and recent studies on the illusions and characteristics associated with spatial disorientation and SMS during weightlessness, such as cognitive map and mental rotation, the visual reorientation and inversion illusions, and orientation preferences between visual scenes and the internal z-axis of the body. The relationships between the SV and the incidence of and susceptibility to SMS as well as spatial disorientation were addressed. A consistent framework was presented to understand and explain SMS characteristics in more detail on the basis of the SV conflict theory, which is expected to be more advantageous in SMS prediction, prevention, and training.

Pharmacy students' perceptions of natural science and mathematics subjects.

Science.gov (United States)

Prescott, Julie; Wilson, Sarah Ellen; Wan, Kai-Wai

2014-08-15

To determine the level of importance pharmacy students placed on science and mathematics subjects for pursuing a career in pharmacy. Two hundred fifty-four students completed a survey instrument developed to investigate students' perceptions of the relevance of science and mathematics subjects to a career in pharmacy. Pharmacy students in all 4 years of a master of pharmacy (MPharm) degree program were invited to complete the survey instrument. Students viewed chemistry-based and biology-based subjects as relevant to a pharmacy career, whereas mathematics subjects such as physics, logarithms, statistics, and algebra were not viewed important to a career in pharmacy. Students' experience in pharmacy and year of study influenced their perceptions of subjects relevant to a pharmacy career. Pharmacy educators need to consider how they can help students recognize the importance of scientific knowledge earlier in the pharmacy curriculum.

Polarity-Dependent Misperception of Subjective Visual Vertical during and after Transcranial Direct Current Stimulation (tDCS).

Science.gov (United States)

Santos-Pontelli, Taiza E G; Rimoli, Brunna P; Favoretto, Diandra B; Mazin, Suleimy C; Truong, Dennis Q; Leite, Joao P; Pontes-Neto, Octavio M; Babyar, Suzanne R; Reding, Michael; Bikson, Marom; Edwards, Dylan J

2016-01-01

Pathologic tilt of subjective visual vertical (SVV) frequently has adverse functional consequences for patients with stroke and vestibular disorders. Repetitive transcranial magnetic stimulation (rTMS) of the supramarginal gyrus can produce a transitory tilt on SVV in healthy subjects. However, the effect of transcranial direct current stimulation (tDCS) on SVV has never been systematically studied. We investigated whether bilateral tDCS over the temporal-parietal region could result in both online and offline SVV misperception in healthy subjects. In a randomized, sham-controlled, single-blind crossover pilot study, thirteen healthy subjects performed tests of SVV before, during and after the tDCS applied over the temporal-parietal region in three conditions used on different days: right anode/left cathode; right cathode/left anode; and sham. Subjects were blind to the tDCS conditions. Montage-specific current flow patterns were investigated using computational models. SVV was significantly displaced towards the anode during both active stimulation conditions when compared to sham condition. Immediately after both active conditions, there were rebound effects. Longer lasting after-effects towards the anode occurred only in the right cathode/left anode condition. Current flow models predicted the stimulation of temporal-parietal regions under the electrodes and deep clusters in the posterior limb of the internal capsule. The present findings indicate that tDCS over the temporal-parietal region can significantly alter human SVV perception. This tDCS approach may be a potential clinical tool for the treatment of SVV misperception in neurological patients.

Perception of faces in schizophrenia: Subjective (self-report) vs. objective (psychophysics) assessments

Science.gov (United States)

Chen, Yue; Ekstrom, Tor

2016-01-01

Objectives Face perception impairment in schizophrenia has been demonstrated, mostly through experimental studies. How this laboratory-defined behavioral impairment is associated with patients’ perceptual experience of various faces in everyday life is however unclear. This question is important because a first-person account of face perception has direct consequences on social functioning of patients. In this study, we adapted and administered a self-reported questionnaire on narrative perceptual experience of faces along with psychophysical assessments of face perception in schizophrenia. Methods The self-reported questionnaire includes six rating items of face-related functioning in everyday life, providing a subjective measure of face perception. The psychophysical assessment determines perceptual threshold for discriminating different facial identities, providing an objective measure of face perception. Results Compared to controls (n=25), patients (n=35) showed significantly lower scores (worse performance) in the subjective assessment and significantly higher thresholds (worse performance) in the objective assessment. The subjective and objective face perception assessments were moderately correlated in controls but not in patients. The subjective face perception assessments were significantly correlated with measurements of a social cognitive ability (Theory of Mind), again in controls but not in patients. Conclusion These results suggest that in schizophrenia the quality of face-related functioning in everyday life is degraded and the role that basic face discrimination capacity plays in face-related everyday functioning is disrupted. PMID:26938027

students' perception of teacher's knowledge of subject matter

African Journals Online (AJOL)

ALEXANDER E. TIMOTHY

COPYRIGHT© BACHUDO SCIENCE CO. ... students' perception of teachers' knowledge of subject matter as perceived by students on reading ... percent and above in English language (WAEC,. 2007). ... to the learners. ... mathematics.

Perception of self-tilt in a true and illusory vertical plane

Science.gov (United States)

Groen, Eric L.; Jenkin, Heather L.; Howard, Ian P.; Oman, C. M. (Principal Investigator)

2002-01-01

A tilted furnished room can induce strong visual reorientation illusions in stationary subjects. Supine subjects may perceive themselves upright when the room is tilted 90 degrees so that the visual polarity axis is kept aligned with the subject. This 'upright illusion' was used to induce roll tilt in a truly horizontal, but perceptually vertical, plane. A semistatic tilt profile was applied, in which the tilt angle gradually changed from 0 degrees to 90 degrees, and vice versa. This method produced larger illusory self-tilt than usually found with static tilt of a visual scene. Ten subjects indicated self-tilt by setting a tactile rod to perceived vertical. Six of them experienced the upright illusion and indicated illusory self-tilt with an average gain of about 0.5. This value is smaller than with true self-tilt (0.8), but comparable to the gain of visually induced self-tilt in erect subjects. Apparently, the contribution of nonvisual cues to gravity was independent of the subject's orientation to gravity itself. It therefore seems that the gain of visually induced self-tilt is smaller because of lacking, rather than conflicting, nonvisual cues. A vector analysis is used to discuss the results in terms of relative sensory weightings.

Objective quality assessment of stereoscopic images with vertical disparity using EEG

Science.gov (United States)

Shahbazi Avarvand, Forooz; Bosse, Sebastian; Müller, Klaus-Robert; Schäfer, Ralf; Nolte, Guido; Wiegand, Thomas; Curio, Gabriel; Samek, Wojciech

2017-08-01

Objective. Neurophysiological correlates of vertical disparity in 3D images are studied in an objective approach using EEG technique. These disparities are known to negatively affect the quality of experience and to cause visual discomfort in stereoscopic visualizations. Approach. We have presented four conditions to subjects: one in 2D and three conditions in 3D, one without vertical disparity and two with different vertical disparity levels. Event related potentials (ERPs) are measured for each condition and the differences between ERP components are studied. Analysis is also performed on the induced potentials in the time frequency domain. Main results. Results show that there is a significant increase in the amplitude of P1 components in 3D conditions in comparison to 2D. These results are consistent with previous studies which have shown that P1 amplitude increases due to the depth perception in 3D compared to 2D. However the amplitude is significantly smaller for maximum vertical disparity (3D-3) in comparison to 3D with no vertical disparity. Our results therefore suggest that the vertical disparity in 3D-3 condition decreases the perception of depth compared to other 3D conditions and the amplitude of P1 component can be used as a discriminative feature. Significance. The results show that the P1 component increases in amplitude due to the depth perception in the 3D stimuli compared to the 2D stimulus. On the other hand the vertical disparity in the stereoscopic images is studied here. We suggest that the amplitude of P1 component is modulated with this parameter and decreases due to the decrease in the perception of depth.

Perception of faces in schizophrenia: Subjective (self-report) vs. objective (psychophysics) assessments.

Science.gov (United States)

Chen, Yue; Ekstrom, Tor

2016-05-01

Face perception impairment in schizophrenia has been demonstrated, mostly through experimental studies. How this laboratory-defined behavioral impairment is associated with patients' perceptual experience of various faces in everyday life is however unclear. This question is important because a first-person account of face perception has direct consequences on social functioning of patients. In this study, we adapted and administered a self-reported questionnaire on narrative perceptual experience of faces along with psychophysical assessments of face perception in schizophrenia. The self-reported questionnaire includes six rating items of face-related functioning in everyday life, providing a subjective measure of face perception. The psychophysical assessment determines perceptual threshold for discriminating different facial identities, providing an objective measure of face perception. Compared to controls (n = 25), patients (n = 35) showed significantly lower scores (worse performance) in the subjective assessment and significantly higher thresholds (worse performance) in the objective assessment. The subjective and objective face perception assessments were moderately correlated in controls but not in patients. The subjective face perception assessments were significantly correlated with measurements of a social cognitive ability (Theory of Mind), again in controls but not in patients. These results suggest that in schizophrenia the quality of face-related functioning in everyday life is degraded and the role that basic face discrimination capacity plays in face-related everyday functioning is disrupted. Copyright © 2016 Elsevier Ltd. All rights reserved.

Do different vertical positions of maxillary central incisors influence smile esthetics perception?

Science.gov (United States)

Menezes, Erica Bretas Cabral; Bittencourt, Marcos Alan Vieira; Machado, Andre Wilson

2017-01-01

The purpose of this study was to determine the perception of smile esthetics among orthodontists and layperson, with respect to different maxillary central incisors vertical positions in full-face and close-up smile analyses. Frontal photographs of the smiles of two adult women were used. Images were altered to create a symmetrical image with the gingival margin levels of the maxillary canines matching the central incisors and a 1.0-mm central-to-lateral incisal step. Later, the images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. The images were randomly assembled in an album, which was given to 114 judges, 57 orthodontists and 57 laypersons, who were asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were statistically analyzed by means of 1-way analysis of variance with the Tukey post-hoc test and the Student t test. The highest rated smiles showed two notable characteristics: a) the central incisor gingival margins matched or were 0.5 mm below the line of the canine gingival margins and; b) the central-to-lateral incisal step was 1.0 to 1.5 mm. The worst smiles showed two notable characteristics: a) the central incisor gingival margins were 1.0 mm above or 1.5 mm below the canine gingival margins and; b) no step between the centrals and laterals or a 2.5-mm step. The vertical position of the maxillary central incisors significantly affected the perception of the smile esthetics, whereas slightly extruded central incisors were more esthetically preferred than intruded.

Do different vertical positions of maxillary central incisors influence smile esthetics perception?

Directory of Open Access Journals (Sweden)

Erica Bretas Cabral Menezes

Full Text Available ABSTRACT INTRODUCTION: The purpose of this study was to determine the perception of smile esthetics among orthodontists and layperson, with respect to different maxillary central incisors vertical positions in full-face and close-up smile analyses. METHODS: Frontal photographs of the smiles of two adult women were used. Images were altered to create a symmetrical image with the gingival margin levels of the maxillary canines matching the central incisors and a 1.0-mm central-to-lateral incisal step. Later, the images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. The images were randomly assembled in an album, which was given to 114 judges, 57 orthodontists and 57 laypersons, who were asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were statistically analyzed by means of 1-way analysis of variance with the Tukey post-hoc test and the Student t test. RESULTS: The highest rated smiles showed two notable characteristics: a the central incisor gingival margins matched or were 0.5 mm below the line of the canine gingival margins and; b the central-to-lateral incisal step was 1.0 to 1.5 mm. The worst smiles showed two notable characteristics: a the central incisor gingival margins were 1.0 mm above or 1.5 mm below the canine gingival margins and; b no step between the centrals and laterals or a 2.5-mm step. CONCLUSION: The vertical position of the maxillary central incisors significantly affected the perception of the smile esthetics, whereas slightly extruded central incisors were more esthetically preferred than intruded.

From Perception to Subject: The Bergsonian Reversal

Directory of Open Access Journals (Sweden)

Messay Kebede

2014-09-01

Full Text Available In lieu of an abstract, here is the opening paragraph to the essay:What singles out philosophical analyses of perception is the challenge to common sense, that is, to the spontaneous, instinctive belief that an external world exists and that it is similar to the perception we have of it. Even those theories that refrain from questioning the independent existence of the world concede that the resemblance of whatever is out there to the perceived reality is anything but assured. Henri Bergson proposes a theory of perception that not only restores the common belief in the existence of an external world, but also goes a long way in narrowing the alleged disparity between perception and the objective world. With few exceptions, Bergson’s theory of perception has been either ignored or misunderstood. Through a close reading of the first chapter of Matter and Memory, the paper argues, in addition to correcting misreadings, that the strength and originality of Bergson’s theory lie in the reversal of the method of explaining perception from the premise of a given subject, a premise shared by all idealist and realist theories as well as phenomenology. This de-subjectification proposes an approach deriving perception from the interactions of objects while countering the materialist theory of the brain as an organ of representation. The paper contends that the Bergsonian elucidation of the brain as an organ of simulation both anticipates the findings of the sensorimotor theory and overcomes its limitation by showing how simulation inserts indetermination into materiality, thereby actualizing consciousness.

Soil structure interaction analysis of buried tank subjected to vertical excitations

International Nuclear Information System (INIS)

Wong, C.K.; Stine, M.; Wagenblast, G.; Farnworth, S.

1995-09-01

Underground High Level Waste Storage Tanks are subjected to strigent seismic requirements At some DOE sites, many existing waste storage tanks are of the double-shell tank design. In this configuration, the concrete outer structure acts as the vault and provides secondary confinement for the primary steel waste storage tank. To ensure the safety of the design and a good understanding of the seismic response of the concrete confinement structure, seismic analysis, including the effects of Soil-Structure Interaction (SSI), is generally performed with special purpose SSI computer analysis programs. Generally, the seismic SSI response due to vertical excitation is considered to be secondary to those of the horizontal excitation. In this paper, a detailed evaluation of the SSI response due to vertical excitation is presented and is shown to merit equal consideration relative to the horizontal excitation. The geometry and relative dimensions (i.e. flexibility) of the structure can have significant influence on the vertical seismic SSI response in local region(s) of the concrete structure

Material resources availability, parent subject perception and school ...

African Journals Online (AJOL)

Students' poor performance in the Yoruba language is being considered a serious problem by researchers and education stakeholders. Despite their efforts, no appreciable improvement is noticeable for hardly are enough researches on the extent to which school material resources availability, parental subject perception ...

Adaptive Changes in the Perception of Fast and Slow Movement at Different Head Positions.

Science.gov (United States)

Panichi, Roberto; Occhigrossi, Chiara; Ferraresi, Aldo; Faralli, Mario; Lucertini, Marco; Pettorossi, Vito E

2017-05-01

This paper examines the subjective sense of orientation during asymmetric body rotations in normal subjects. Self-motion perception was investigated in 10 healthy individuals during asymmetric whole-body rotation with different head orientations. Both on-vertical axis and off-vertical axis rotations were employed. Subjects tracked a remembered earth-fixed visual target while rotating in the dark for four cycles of asymmetric rotation (two half-sinusoidal cycles of the same amplitude, but of different duration). The rotations induced a bias in the perception of velocity (more pronounced with fast than with slow motion). At the end of rotation, a marked target position error (TPE) was present. For the on-vertical axis rotations, the TPE was no different if the rotations were performed with a 30° nose-down, a 60° nose-up, or a 90° side-down head tilt. With off-vertical axis rotations, the simultaneous activation of the semicircular canals and otolithic receptors produced a significant increase of TPE for all head positions. This difference between on-vertical and off-vertical axis rotation was probably partly due to the vestibular transfer function and partly due to different adaptation to the speed of rotation. Such a phenomenon might be generated in different components of the vestibular system. The adaptive process enhancing the perception of dynamic movement around the vertical axis is not related to the specific semicircular canals that are activated; the addition of an otolithic component results in a significant increase of the TPE.Panichi R, Occhigrossi C, Ferraresi A, Faralli M, Lucertini M, Pettorossi VE. Adaptive changes in the perception of fast and slow movement at different head positions. Aerosp Med Hum Perform. 2017; 88(5):463-468.

perception to cadaver dissection and views on anatomy as a subject

African Journals Online (AJOL)

However, literature on medical students' perceptions on cadaver dissection and their opinions on anatomy as a subject is scanty ... Key words: Dissection, Perceptions, Cadaver, Anatomy. INTRODUCTION. Dissection has been the .... attention they give to the learning of anatomy, and this may possibly explain the relatively.

Evolution of Subjective Hurricane Risk Perceptions: A Bayesian Approach

OpenAIRE

David Kelly; David Letson; Forest Nelson; David S. Nolan; Daniel Solis

2009-01-01

This paper studies how individuals update subjective risk perceptions in response to hurricane track forecast information, using a unique data set from an event market, the Hurricane Futures Market (HFM). We derive a theoretical Bayesian framework which predicts how traders update their perceptions of the probability of a hurricane making landfall in a certain range of coastline. Our results suggest that traders behave in a way consistent with Bayesian updating but this behavior is based on t...

Linguistic Means of Depersonalization and Dematerialization in the Descriptions of Subjective Perception of Time

Directory of Open Access Journals (Sweden)

Ella V. Nesterik

2013-01-01

Full Text Available This article analyses linguistic means of depersonalization and dematerialization in the descriptions of subjective perception of time by characters, detects functions, fulfilled by them in such contexts. Subjective perception of time is considered as a text category and is studied in terms of text linguistics

Flow and pressure drop fluctuations in a vertical tube subject to low frequency oscillations

International Nuclear Information System (INIS)

Pendyala, Rajashekhar; Jayanti, Sreenivas; Balakrishnan, A.R.

2008-01-01

Heat transfer and other equipment mounted on off-shore platforms may be subjected to low frequency oscillations. The effect of these oscillations, typically in the frequency range of 0.1-1 Hz, on the flow rate and pressure drop in a vertical tube has been studied experimentally in the present work. A 1.75 m-long vertical tube of inner diameter 0.016 m was mounted on a plate and the whole plate was subjected to oscillations in the vertical plane using a mechanical simulator capable of providing low frequency oscillations in the range of 8-30 cycles/min at an amplitude of 0.125 m. The effect of the oscillations on the flow rate and the pressure drop has been measured systematically in the Reynolds number range 500-6500. The induced flow rate fluctuations were found to be dependent on the Reynolds number with stronger fluctuations at lower Reynolds numbers. The effective friction factor, based on the mean pressure drop and the mean flow rate, was also found to be higher than expected. Correlations have been developed to quantify this Reynolds number dependence

Flow and pressure drop fluctuations in a vertical tube subject to low frequency oscillations

Energy Technology Data Exchange (ETDEWEB)

Pendyala, Rajashekhar; Jayanti, Sreenivas [Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Balakrishnan, A.R. [Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 600036 (India)], E-mail: arbala@iitm.ac.in

2008-01-15

Heat transfer and other equipment mounted on off-shore platforms may be subjected to low frequency oscillations. The effect of these oscillations, typically in the frequency range of 0.1-1 Hz, on the flow rate and pressure drop in a vertical tube has been studied experimentally in the present work. A 1.75 m-long vertical tube of inner diameter 0.016 m was mounted on a plate and the whole plate was subjected to oscillations in the vertical plane using a mechanical simulator capable of providing low frequency oscillations in the range of 8-30 cycles/min at an amplitude of 0.125 m. The effect of the oscillations on the flow rate and the pressure drop has been measured systematically in the Reynolds number range 500-6500. The induced flow rate fluctuations were found to be dependent on the Reynolds number with stronger fluctuations at lower Reynolds numbers. The effective friction factor, based on the mean pressure drop and the mean flow rate, was also found to be higher than expected. Correlations have been developed to quantify this Reynolds number dependence.

Factors influencing subjective perceptions of everyday occupations: comparing day centre attendees with non-attendees.

Science.gov (United States)

Argentzell, Elisabeth; Leufstadius, Christel; Eklund, Mona

2012-01-01

Subjective perceptions of everyday occupations are important for the well-being of people with psychiatric disabilities (PD) and are likely to vary with factors such as attending a day centre or not, activity level, self-mastery, sociodemographic and clinical factors. To explore differences in subjective perceptions of occupation and activity level between day centre attendees and non-attendees, and to investigate factors of importance for the subjective perceptions of occupations. The study groups comprised 175 participants: 93 day centre attendees and 82 non-attendees. Data were collected with instruments concerning; subjective perceptions of everyday occupations, activity level, self-mastery, and sociodemographic and clinical factors. Day centre attendees perceived higher levels of occupational value and activity level, while the groups perceived a similar level of satisfaction with daily occupations. For the total sample, self-mastery influenced both valued and satisfying everyday occupations while only value was affected by activity level. Satisfaction with daily occupation increased with age and both value and satisfaction increased with lower levels of psychiatric symptoms. Day centres provide perceptions of occupational value and stimulate activity. Non-differences between the groups regarding satisfaction with everyday occupations implied, however, that day centres might not cover all relevant occupational needs.

The elevator illusion results from the combination of body orientation and egocentric perception.

Science.gov (United States)

Paillard, A; Denise, P; Barraud, P-A; Roux, A; Cian, C

2009-10-30

Perception of body orientation and apparent location of objects are altered when humans are using assisted means of locomotion and the resultant of the imposed acceleration and gravity is no longer aligned with the gravitational vertical. As the otolithic system cannot discriminate the acceleration of gravity from sustained inertial accelerations, individuals would perceive the resultant acceleration vector (GiA) as the vertical. However, when subjects are aligned on the GiA, an increase in the magnitude of GiA induced a lowering of the apparent visual horizon (i.e. "elevator illusion"). The main aim of this study was to quantify the contribution of body and egocentric perception in the elevator illusion. While being exposed to 1G and 1.3G and aligned on the GiA acceleration, subjects (N=20) were asked (1) to set a luminous target to the subjective horizon, (2) to set a luminous target on "straight ahead" position (egocentric task) and (3) to rotate a tilting tube to their subjective perception of body orientation. Results showed that increasing GiA lowered horizon and egocentric settings and induces a backward body tilt perception. Moreover, the elevator illusion can be expressed as the additive combination of two processes: one that is dependent on body tilt perception, and the other that is dependent on egocentric perception. Both misperceptions in hypergravity may be considered to be a consequence of excessive shearing of the otolith organs. However large inter-individual differences in body tilt perception were observed. This last result was discussed in terms of the contribution of extravestibular graviceptors.

Convective heat transfer in single-phase flow in a vertical tube subjected to axial low frequency oscillations

Energy Technology Data Exchange (ETDEWEB)

Pendyala, Rajashekhar; Jayanti, Sreenivas; Balakrishnan, A.R. [Indian Institute of Technology Madras, Department of Chemical Engineering, Chennai, Tamil Nadu (India)

2008-05-15

The effect of oscillations on the heat transfer in a vertical tube has been studied experimentally. A vertical tube was mounted on a plate and the whole plate was subjected to oscillations in the vertical plane using a mechanical oscillator to provide low frequency oscillations. A section of the tube in the middle is subjected to a constant heat flux. The effect of the oscillations on the heat transfer coefficient has been examined. It was found that the heat transfer coefficient increased with oscillations in the laminar regime. In turbulent flow regime (Re > 2,100) it is found that the effect of oscillations did not show any change. A correlation has been developed for enhancement of the local Nusselt number in terms of the effective acceleration and Reynolds number. Using this, an expression has been proposed to calculate the mean Nusselt number as a function of the tube length. (orig.)

An anatomical and psychophysical comparison of subjective verticals in patients with right brain damage.

Science.gov (United States)

Rousseaux, Marc; Braem, Bérenger; Honoré, Jacques; Saj, Arnaud

2015-08-01

Brain hemisphere lesions often cause a contralesional tilt of the subjective vertical (SV) a phenomenon related to spatial neglect and postural disorders. Depending on the method employed, different perceptual systems come into play when this gravitational vertical is assessed. Here, we compared the anatomical and psychophysical characteristics of modality-dependent SV biases in patients with right hemisphere stroke. The SV was measured with visual, haptic and visual-haptic modalities (SV, SVV, SVHV) in 46 patients with a relatively recent stroke. Voxel-based lesion-symptom mapping (performed with NPM(®)) was used to highlight brain areas in which lesions best explained the severity of task biases (p rights reserved.

Textured insoles reduce vertical loading rate and increase subjective plantar sensation in overground running.

Science.gov (United States)

Wilkinson, Michael; Ewen, Alistair; Caplan, Nicholas; O'leary, David; Smith, Neil; Stoneham, Richard; Saxby, Lee

2018-05-01

The effect of textured insoles on kinetics and kinematics of overground running was assessed. 16 male injury-free-recreational runners attended a single visit (age 23 ± 5 yrs; stature 1.78 ± 0.06 m; mass 72.6 ± 9.2 kg). Overground 15-m runs were completed in flat, canvas plimsolls both with and without textured insoles at self-selected velocity on an indoor track in an order that was balanced among participants. Average vertical loading rate and peak vertical force (F peak ) were captured by force platforms. Video footage was digitised for sagittal plane hip, knee and ankle angles at foot strike and mid stance. Velocity, stride rate and length and contact and flight time were determined. Subjectively rated plantar sensation was recorded by visual scale. 95% confidence intervals estimated mean differences. Smallest worthwhile change in loading rate was defined as standardised reduction of 0.54 from a previous comparison of injured versus non-injured runners. Loading rate decreased (-25 to -9.3 BW s -1 ; 60% likely beneficial reduction) and plantar sensation was increased (46-58 mm) with the insole. F peak (-0.1 to 0.14 BW) and velocity (-0.02 to 0.06 m s -1 ) were similar. Stride length, flight and contact time were lower (-0.13 to -0.01 m; -0.02 to-0.01 s; -0.016 to -0.006 s) and stride rate was higher (0.01-0.07 steps s -1 ) with insoles. Textured insoles elicited an acute, meaningful decrease in vertical loading rate in short distance, overground running and were associated with subjectively increased plantar sensation. Reduced vertical loading rate could be explained by altered stride characteristics.

Gaze direction effects on perceptions of upper limb kinesthetic coordinate system axes.

Science.gov (United States)

Darling, W G; Hondzinski, J M; Harper, J G

2000-12-01

The effects of varying gaze direction on perceptions of the upper limb kinesthetic coordinate system axes and of the median plane location were studied in nine subjects with no history of neuromuscular disorders. In two experiments, six subjects aligned the unseen forearm to the trunk-fixed anterior-posterior (a/p) axis and earth-fixed vertical while gazing at different visual targets using either head or eye motion to vary gaze direction in different conditions. Effects of support of the upper limb on perceptual errors were also tested in different conditions. Absolute constant errors and variable errors associated with forearm alignment to the trunk-fixed a/p axis and earth-fixed vertical were similar for different gaze directions whether the head or eyes were moved to control gaze direction. Such errors were decreased by support of the upper limb when aligning to the vertical but not when aligning to the a/p axis. Regression analysis showed that single trial errors in individual subjects were poorly correlated with gaze direction, but showed a dependence on shoulder angles for alignment to both axes. Thus, changes in position of the head and eyes do not influence perceptions of upper limb kinesthetic coordinate system axes. However, dependence of the errors on arm configuration suggests that such perceptions are generated from sensations of shoulder and elbow joint angle information. In a third experiment, perceptions of median plane location were tested by instructing four subjects to place the unseen right index fingertip directly in front of the sternum either by motion of the straight arm at the shoulder or by elbow flexion/extension with shoulder angle varied. Gaze angles were varied to the right and left by 0.5 radians to determine effects of gaze direction on such perceptions. These tasks were also carried out with subjects blind-folded and head orientation varied to test for effects of head orientation on perceptions of median plane location. Constant

Restrictions to Pharmacy Ownership and Vertical Integration in Estonia-Perception of Different Stakeholders.

Science.gov (United States)

Gross, Marit; Volmer, Daisy

2016-04-19

From 2020, the ownership of community pharmacies in Estonia will be limited to the pharmacy profession, and the vertical integration of wholesale companies and community pharmacies will not be allowed. The aim of this study was to evaluate the perception of different stakeholders in primary healthcare toward the new regulations of the community pharmacy sector in Estonia. A qualitative electronic survey was distributed to the main stakeholders in primary healthcare and higher education institutions providing pharmacy education ( n = 40) in May 2015. For data analysis, the systematic text condensation method was used. The study participants described two opposing positions regarding the development of community pharmacies in the future. Reform supporters emphasized increased professional independence and more healthcare-oriented operation of community pharmacies. Reform opponents argued against these ideas as community pharmacists do not have sufficient practical experience and finances to ensure sustainable development of the community pharmacy sector in Estonia. Based on the current perception of all respondents, the future operation of the community pharmacy sector in Estonia is unclear and there is urgent need for implementation criteria for the new regulations.

Associated Information Increases Subjective Perception of Duration.

Science.gov (United States)

Schweitzer, Richard; Trapp, Sabrina; Bar, Moshe

2017-08-01

Our sense of time is prone to various biases. For instance, one factor that can dilate an event's perceived duration is the violation of predictions; when a series of repeated stimuli is interrupted by an unpredictable oddball. On the other hand, when the probability of a repetition itself is manipulated, predictable conditions can also increase estimated duration. This suggests that manipulations of expectations have different or even opposing effects on time perception. In previous studies, expectations were generated because stimuli were repeated or because the likelihood of a sequence or a repetition was varied. In the natural environment, however, expectations are often built via associative processes, for example, the context of a kitchen promotes the expectation of plates, appliances, and other associated objects. Here, we manipulated such association-based expectations by using oddballs that were either contextually associated or nonassociated with the standard items. We find that duration was more strongly overestimated for contextually associated oddballs. We reason that top-down attention is biased toward associated information, and thereby dilates subjective duration for associated oddballs. Based on this finding, we propose an interplay between top-down attention and predictive processing in the perception of time.

Temporal cognition: Connecting subjective time to perception, attention, and memory.

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Matthews, William J; Meck, Warren H

2016-08-01

Time is a universal psychological dimension, but time perception has often been studied and discussed in relative isolation. Increasingly, researchers are searching for unifying principles and integrated models that link time perception to other domains. In this review, we survey the links between temporal cognition and other psychological processes. Specifically, we describe how subjective duration is affected by nontemporal stimulus properties (perception), the allocation of processing resources (attention), and past experience with the stimulus (memory). We show that many of these connections instantiate a "processing principle," according to which perceived time is positively related to perceptual vividity and the ease of extracting information from the stimulus. This empirical generalization generates testable predictions and provides a starting-point for integrated theoretical frameworks. By outlining some of the links between temporal cognition and other domains, and by providing a unifying principle for understanding these effects, we hope to encourage time-perception researchers to situate their work within broader theoretical frameworks, and that researchers from other fields will be inspired to apply their insights, techniques, and theorizing to improve our understanding of the representation and judgment of time. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

As time goes by: Oxytocin influences the subjective perception of time in a social context.

Science.gov (United States)

Colonnello, Valentina; Domes, Gregor; Heinrichs, Markus

2016-06-01

Time perception depends on an event's emotional relevance to the beholder; a subjective time dilation effect is associated with self-relevant, emotionally salient stimuli. Previous studies have revealed that oxytocin modulates the salience of social stimuli and attention to social cues. However, whether the oxytocin system is involved in human subjective time perception is unknown. The aim of the present study was to investigate whether increased oxytocin levels would induce a time dilation effect for self-relevant, positive social cues. In a double-blind, placebo-controlled, between-subject design, heterosexual men were administered intranasal oxytocin or placebo. After about 50min, participants completed a time-bisection task in which they estimated lengths of exposure to happy female faces (self-relevant positive stimuli, based on sexual orientation), emotionally neutral and negative female faces (control), and happy, neutral, and negative male faces (control). Oxytocin induced a subjective time dilation effect for happy female faces and a time compression effect for happy male faces. Our results provide evidence that oxytocin influences time perception, a primary form of human subjectivity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Incidence of vertical phoria on postural control during binocular vision: what perspective for prevention to nonspecific chronic pain management?

Science.gov (United States)

Matheron, Eric; Kapoula, Zoï

2015-01-01

Vertical heterophoria (VH) is the latent vertical misalignment of the eyes when the retinal images are dissociated, vertical orthophoria (VO) when there is no misalignment. Studies on postural control, during binocular vision in upright stance, reported that healthy subjects with small VH vs. VO are less stable, but the experimental cancellation of VH with an appropriate prism improves postural stability. The same behavior was recorded in nonspecific chronic back pain subjects, all with VH. It was hypothesized that, without refraction problems, VH indicates a perturbation of the somaesthetic cues required in the sensorimotor loops involved in postural control and the capacity of the CNS to optimally integrate these cues, suggesting prevention possibilities. Sensorimotor conflict can induce pain and modify sensory perception in some healthy subjects; some nonspecific pain or chronic pain could result from such prolonged conflict in which VH could be a sign, with new theoretical and clinical implications.

Impaired perception of surface tilt in progressive supranuclear palsy.

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Marian L Dale

Full Text Available Progressive supranuclear palsy (PSP is characterized by early postural instability and backward falls. The mechanisms underlying backward postural instability in PSP are not understood. The aim of this study was to test the hypothesis that postural instability in PSP is a result of dysfunction in the perception of postural verticality.We gathered posturography data on 12 subjects with PSP to compare with 12 subjects with idiopathic Parkinson's Disease (PD and 12 healthy subjects. Objective tests of postural impairment included: dynamic sensory perception tests of gravity and of surface oscillations, postural responses to surface perturbations, the sensory organization test of postural sway under altered sensory conditions and limits of stability in stance.Perception of toes up (but not toes down surface tilt was reduced in subjects with PSP compared to both control subjects (p≤0.001 standing, p≤0.007 seated and subjects with PD (p≤0.03 standing, p≤0.04 seated. Subjects with PSP, PD and normal controls accurately perceived the direction of gravity when standing on a tilting surface. Unlike PD and control subjects, subjects with PSP exerted less postural corrective torque in response to toes up surface tilts.Difficulty perceiving backward tilt of the surface or body may account for backward falls and postural impairments in patients with PSP. These observations suggest that abnormal central integration of sensory inputs for perception of body and surface orientation contributes to the pathophysiology of postural instability in PSP.

Restrictions to Pharmacy Ownership and Vertical Integration in Estonia—Perception of Different Stakeholders

Science.gov (United States)

Gross, Marit; Volmer, Daisy

2016-01-01

Objectives: From 2020, the ownership of community pharmacies in Estonia will be limited to the pharmacy profession, and the vertical integration of wholesale companies and community pharmacies will not be allowed. The aim of this study was to evaluate the perception of different stakeholders in primary healthcare toward the new regulations of the community pharmacy sector in Estonia. Methods: A qualitative electronic survey was distributed to the main stakeholders in primary healthcare and higher education institutions providing pharmacy education (n = 40) in May 2015. For data analysis, the systematic text condensation method was used. Results: The study participants described two opposing positions regarding the development of community pharmacies in the future. Reform supporters emphasized increased professional independence and more healthcare-oriented operation of community pharmacies. Reform opponents argued against these ideas as community pharmacists do not have sufficient practical experience and finances to ensure sustainable development of the community pharmacy sector in Estonia. Conclusion: Based on the current perception of all respondents, the future operation of the community pharmacy sector in Estonia is unclear and there is urgent need for implementation criteria for the new regulations. PMID:28970391

Hysteresis of haptic vertical and straight ahead in healthy human subjects

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Tarnutzer Alexander A

2012-09-01

Full Text Available Abstract Background The subjective haptic vertical (SHV task requires subjects to adjust the roll orientation of an object, mostly in the roll plane, in such a way that it is parallel to perceived direction of gravity. Previously we found a tendency for clockwise rod rotations to deviate counter-clockwise and vice versa, indicating hysteresis. However, the contributing factors remained unclear. To clarify this we characterized the SHV in terms of handedness, hand used, direction of hand rotation, type of grasping (wrap vs. precision grip and gender, and compared findings with perceived straight-ahead (PSA. Healthy subjects repetitively performed adjustments along SHV (n = 21 and PSA (n = 10 in complete darkness. Results For both SHV and PSA significant effects of the hand used and the direction of rod/plate rotation were found. The latter effect was similar for SHV and PSA, leading to significantly larger counter-clockwise shifts (relative to true earth-vertical and objective straight-ahead for clockwise rotations compared to counter-clockwise rotations irrespective of the handedness and the type of grip. The effect of hand used, however, was opposite in the two tasks: while the SHV showed a counter-clockwise bias when the right hand was used and no bias for the left hand, in the PSA a counter-clockwise bias was obtained for the left hand without a bias for the right hand. No effects of grip and handedness (studied for SHV only on accuracy were observed, however, SHV precision was significantly (p  Conclusions Unimanual haptic tasks require control for the hand used and the type of grip as these factors significantly affect task performance. Furthermore, aligning objects with the SHV and PSA resulted in systematic direction-dependent deviations that could not be attributed to handedness, the hand used, or the type of grip. These deviations are consistent with hysteresis and are likely not related to gravitational pull, as they were

Autobiographical memories of childhood and sources of subjectivity in parents' perceptions of infant temperament.

Science.gov (United States)

Manczak, Erika M; Mangelsdorf, Sarah C; McAdams, Dan P; Wong, Maria S; Schoppe-Sullivan, Sarah; Brown, Geoffrey L

2016-08-01

The current study examined whether autobiographical memories from parents' own childhoods, prebirth expectations, and personality traits contributed to their perceptions of their infants' temperament. It also investigated whether mothers and fathers differed in the extent to which these three sources of subjectivity predicted their perceptions. During the third trimester of pregnancy, expectant mothers and fathers in 96 families completed assessments of their personality traits and expectations for their children's temperament, as well as provided characteristic memories of their relationships with their own caregivers as children. Memories were then coded for themes of growth versus safety and compared to parents' ratings of perceived child temperament 15 months later. Analyses revealed that, for both parents, prebirth expectations predicted perceptions of positive temperament behaviors. Moreover, fathers who described childhoods characterized by exploration and opportunities for growth also perceived their children as displaying more positive temperamental behaviors, whereas those who described greater safety focus in memories and who had higher levels of negative affectivity reported more negative temperamental behaviors. These findings suggest that mothers' and fathers' perceptions of their children are differently related to psychological variables, including autobiographical memories. In turn, it is possible that these subjective perceptions may affect the parenting environment. Copyright © 2016 Elsevier Inc. All rights reserved.

Predictive modeling of human perception subjectivity: feasibility study of mammographic lesion similarity

Science.gov (United States)

Xu, Songhua; Hudson, Kathleen; Bradley, Yong; Daley, Brian J.; Frederick-Dyer, Katherine; Tourassi, Georgia

2012-02-01

The majority of clinical content-based image retrieval (CBIR) studies disregard human perception subjectivity, aiming to duplicate the consensus expert assessment of the visual similarity on example cases. The purpose of our study is twofold: i) discern better the extent of human perception subjectivity when assessing the visual similarity of two images with similar semantic content, and (ii) explore the feasibility of personalized predictive modeling of visual similarity. We conducted a human observer study in which five observers of various expertise were shown ninety-nine triplets of mammographic masses with similar BI-RADS descriptors and were asked to select the two masses with the highest visual relevance. Pairwise agreement ranged between poor and fair among the five observers, as assessed by the kappa statistic. The observers' self-consistency rate was remarkably low, based on repeated questions where either the orientation or the presentation order of a mass was changed. Various machine learning algorithms were explored to determine whether they can predict each observer's personalized selection using textural features. Many algorithms performed with accuracy that exceeded each observer's self-consistency rate, as determined using a cross-validation scheme. This accuracy was statistically significantly higher than would be expected by chance alone (two-tailed p-value ranged between 0.001 and 0.01 for all five personalized models). The study confirmed that human perception subjectivity should be taken into account when developing CBIR-based medical applications.

Perception of tilt (somatogravic illusion) in response to sustained linear acceleration during space flight

Science.gov (United States)

Clement, G.; Moore, S. T.; Raphan, T.; Cohen, B.

2001-01-01

During the 1998 Neurolab mission (STS-90), four astronauts were exposed to interaural and head vertical (dorsoventral) linear accelerations of 0.5 g and 1 g during constant velocity rotation on a centrifuge, both on Earth and during orbital space flight. Subjects were oriented either left-ear-out or right-ear-out (Gy centrifugation), or lay supine along the centrifuge arm with their head off-axis (Gz centrifugation). Pre-flight centrifugation, producing linear accelerations of 0.5 g and 1 g along the Gy (interaural) axis, induced illusions of roll-tilt of 20 degrees and 34 degrees for gravito-inertial acceleration (GIA) vector tilts of 27 degrees and 45 degrees , respectively. Pre-flight 0.5 g and 1 g Gz (head dorsoventral) centrifugation generated perceptions of backward pitch of 5 degrees and 15 degrees , respectively. In the absence of gravity during space flight, the same centrifugation generated a GIA that was equivalent to the centripetal acceleration and aligned with the Gy or Gz axes. Perception of tilt was underestimated relative to this new GIA orientation during early in-flight Gy centrifugation, but was close to the GIA after 16 days in orbit, when subjects reported that they felt as if they were 'lying on side'. During the course of the mission, inflight roll-tilt perception during Gy centrifugation increased from 45 degrees to 83 degrees at 1 g and from 42 degrees to 48 degrees at 0.5 g. Subjects felt 'upside-down' during in-flight Gz centrifugation from the first in-flight test session, which reflected the new GIA orientation along the head dorsoventral axis. The different levels of in-flight tilt perception during 0.5 g and 1 g Gy centrifugation suggests that other non-vestibular inputs, including an internal estimate of the body vertical and somatic sensation, were utilized in generating tilt perception. Interpretation of data by a weighted sum of body vertical and somatic vectors, with an estimate of the GIA from the otoliths, suggests that

Objective and Subjective Factors of Perception of Russia’s Image in the EU

Directory of Open Access Journals (Sweden)

Мария Игоревна Ведерникова

2016-12-01

Full Text Available The article examines the role of international environment influencing the image of Russia. The author reveals the psychological mechanisms of perception of the image of Russia in the EU. Considerable attention is paid to the analysis of objective and subjective factors constructive and negative perception of Russia and its political leader. Status conflicts are analyzed in the article as well, including methods and techniques of purposeful distortion of the image of Russia in Europe.

[Music therapy in adults with cochlear implants : Effects on music perception and subjective sound quality].

Science.gov (United States)

Hutter, E; Grapp, M; Argstatter, H

2016-12-01

People with severe hearing impairments and deafness can achieve good speech comprehension using a cochlear implant (CI), although music perception often remains impaired. A novel concept of music therapy for adults with CI was developed and evaluated in this study. This study included 30 adults with a unilateral CI following postlingual deafness. The subjective sound quality of the CI was rated using the hearing implant sound quality index (HISQUI) and musical tests for pitch discrimination, melody recognition and timbre identification were applied. As a control 55 normally hearing persons also completed the musical tests. In comparison to normally hearing subjects CI users showed deficits in the perception of pitch, melody and timbre. Specific effects of therapy were observed in the subjective sound quality of the CI, in pitch discrimination into a high and low pitch range and in timbre identification, while general learning effects were found in melody recognition. Music perception shows deficits in CI users compared to normally hearing persons. After individual music therapy in the rehabilitation process, improvements in this delicate area could be achieved.

Evaluation of simulation motion fidelity criteria in the vertical and directional axes

Science.gov (United States)

Schroeder, Jeffery A.

1993-01-01

An evaluation of existing motion fidelity criteria was conducted on the NASA Ames Vertical Motion Simulator. Experienced test pilots flew single-axis repositioning tasks in both the vertical and the directional axes. Using a first-order approximation of a hovering helicopter, tasks were flown with variations only in the filters that attenuate the commands to the simulator motion system. These filters had second-order high-pass characteristics, and the variations were made in the filter gain and natural frequency. The variations spanned motion response characteristics from nearly full math-model motion to fixed-base. Between configurations, pilots recalibrated their motion response perception by flying the task with full motion. Pilots subjectively rated the motion fidelity of subsequent configurations relative to this full motion case, which was considered the standard for comparison. The results suggested that the existing vertical-axis criterion was accurate for combinations of gain and natural frequency changes. However, if only the gain or the natural frequency was changed, the rated motion fidelity was better than the criterion predicted. In the vertical axis, the objective and subjective results indicated that a larger gain reduction was tolerated than the existing criterion allowed. The limited data collected in the yaw axis revealed that pilots had difficulty in distinguishing among the variations in the pure yaw motion cues.

Subjective Risk Assessment and Perception in the Greek and English Bakery Industries

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Evangelos C. Alexopoulos

2009-01-01

Full Text Available Several factors influencing risk perception in the area of occupational health and safety are known, but there is still lack of a full understanding of the ways in which people characterize risk. This study aimed to provide an insight of employee risk assessment and perception in the bakery industry. 87 British and 64 Greek employees in two comparable bakery companies were asked to estimate and evaluate hazards at their workplace. The participants' judgments of 12 hazards—according to 7 risk aspects—were collected and analyzed. Subjective assessment on important occupational hazards included handling heavy loads, repetitiveness, high temperatures, high rate of work, stressful deadlines, and noise. Although limited in the population involved, our findings revealed strong cross-national differences in employee risk perception of specific groups of hazards in the bakery industry. Additional interviews revealed evidence that Greek employees' risk perception depends mostly on work experience while British employees were aware of risks due to company health and safety policy, recognizing that safety is the responsibility of both the management and the worker. Cross-national (cultural factors that influence workforce risk perception and attitudes towards safety have to be taken into account by technical experts and policy makers in the designing of prevention strategies and risk communication.

Subjective Risk Assessment and Perception in the Greek and English Bakery Industries

International Nuclear Information System (INIS)

Alexopoulos, E.C.; Kavadi, Z.; Bakoyannis, G.; Papantonopoulos, S.

2010-01-01

Several factors influencing risk perception in the area of occupational health and safety are known, but there is still lack of a full understanding of the ways in which people characterize risk. This study aimed to provide an insight of employee risk assessment and perception in the bakery industry. 87 British and 64 Greek employees in two comparable bakery companies were asked to estimate and evaluate hazards at their workplace. The participants judgments of 12 hazards according to 7 risk aspects were collected and analyzed. Subjective assessment on important occupational hazards included handling heavy loads, repetitiveness, high temperatures, high rate of work, stressful deadlines, and noise. Although limited in the population involved, our findings revealed strong cross-national differences in employee risk perception of specific groups of hazards in the bakery industry. Additional interviews revealed evidence that Greek employees risk perception depends mostly on work experience while British employees were aware of risks due to company health and safety policy, recognizing that safety is the responsibility of both the management and the worker. Cross-national (cultural) factors that influence workforce risk perception and attitudes towards safety have to be taken into account by technical experts and policy makers in the designing of prevention strategies and risk communication.

The effect of mathematics games to the student perception of mathematics subject: A case study in Sekolah Kebangsaan Bukit Kuda, Klang

Science.gov (United States)

Abdul Hadi, Normi; Mohd Noor, Norlenda; Abd Halim, Suhaila; Alwadood, Zuraida; Khairol Azmi, Nurul Nisa'

2013-04-01

Mathematics is a basic subject in primary and secondary schools. Early exposure to mathematics is very important since it will affect the student perception towards this subject for their entire life. Therefore, a program called 'Mini Hari Matematik' was conducted to expose the basic mathematics concept through some games which fit the knowledge of Standard four and five students. A questionnaire regarding student perception towards this subject was distributed before and after the program. From the analysis, the program has positively changed the student's perception towards mathematics.

Consistency between subjectively and objectively measured hazard perception skills among young male drivers

DEFF Research Database (Denmark)

Abele, Liva; Haustein, Sonja; Møller, Mette

2018-01-01

. Subjective measures of HPS include self-reports derived based on the Hazard Perception Questionnaire (HPQ), Driving Skill Questionnaire (DSQ), and Brief Sensation Seeking Scale (BSSS). Results show that drivers who respond to the hazards on time, as compared to drivers who do not respond, have higher scores......Young male drivers have lower hazard perception skills (HPS) than older and more experienced drivers and a tendency to overestimate their skills in hazardous situations. Both factors contribute to an over-representation in traffic accidents. Based on a sample of 63 drivers aged 18-24, this study...... negatively when the hazard is visible. To enhance the HPS among young drivers, the results of this study suggest that specific hazard perception training is relevant, especially for hazards that require more advanced HPS....

Effect of Postural Control Demands on Early Visual Evoked Potentials during a Subjective Visual Vertical Perception Task in Adolescents with Idiopathic Scoliosis.

Science.gov (United States)

Chang, Yi-Tzu; Meng, Ling-Fu; Chang, Chun-Ju; Lai, Po-Liang; Lung, Chi-Wen; Chern, Jen-Suh

2017-01-01

Subjective visual vertical (SVV) judgment and standing stability were separately investigated among patients with adolescent idiopathic scoliosis (AIS). Although, one study has investigated the central mechanism of stability control in the AIS population, the relationships between SVV, decreased standing stability, and AIS have never been investigated. Through event-related potentials (ERPs), the present study examined the effect of postural control demands (PDs) on AIS central mechanisms related to SVV judgment and standing stability to elucidate the time-serial stability control process. Thirteen AIS subjects (AIS group) and 13 age-matched adolescents (control group) aged 12-18 years were recruited. Each subject had to complete an SVV task (i.e., the modified rod-and-frame [mRAF] test) as a stimulus, with online electroencephalogram recording being performed in the following three standing postures: feet shoulder-width apart standing, feet together standing, and tandem standing. The behavioral performance in terms of postural stability (center of pressure excursion), SVV (accuracy and reaction time), and mRAF-locked ERPs (mean amplitude and peak latency of the P1, N1, and P2 components) was then compared between the AIS and control groups. In the behavioral domain, the results revealed that only the AIS group demonstrated a significantly accelerated SVV reaction time as the PDs increased. In the cerebral domain, significantly larger P2 mean amplitudes were observed during both feet shoulder-width-apart standing and feet together standing postures compared with during tandem standing. No group differences were noted in the cerebral domain. The results indicated that (1) during the dual-task paradigm, a differential behavioral strategy of accelerated SVV reaction time was observed in the AIS group only when the PDs increased and (2) the decrease in P2 mean amplitudes with the increase in the PD levels might be direct evidence of the competition for central

Effect of Postural Control Demands on Early Visual Evoked Potentials during a Subjective Visual Vertical Perception Task in Adolescents with Idiopathic Scoliosis

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Yi-Tzu Chang

2017-06-01

Full Text Available Subjective visual vertical (SVV judgment and standing stability were separately investigated among patients with adolescent idiopathic scoliosis (AIS. Although, one study has investigated the central mechanism of stability control in the AIS population, the relationships between SVV, decreased standing stability, and AIS have never been investigated. Through event-related potentials (ERPs, the present study examined the effect of postural control demands (PDs on AIS central mechanisms related to SVV judgment and standing stability to elucidate the time-serial stability control process. Thirteen AIS subjects (AIS group and 13 age-matched adolescents (control group aged 12–18 years were recruited. Each subject had to complete an SVV task (i.e., the modified rod-and-frame [mRAF] test as a stimulus, with online electroencephalogram recording being performed in the following three standing postures: feet shoulder-width apart standing, feet together standing, and tandem standing. The behavioral performance in terms of postural stability (center of pressure excursion, SVV (accuracy and reaction time, and mRAF-locked ERPs (mean amplitude and peak latency of the P1, N1, and P2 components was then compared between the AIS and control groups. In the behavioral domain, the results revealed that only the AIS group demonstrated a significantly accelerated SVV reaction time as the PDs increased. In the cerebral domain, significantly larger P2 mean amplitudes were observed during both feet shoulder-width-apart standing and feet together standing postures compared with during tandem standing. No group differences were noted in the cerebral domain. The results indicated that (1 during the dual-task paradigm, a differential behavioral strategy of accelerated SVV reaction time was observed in the AIS group only when the PDs increased and (2 the decrease in P2 mean amplitudes with the increase in the PD levels might be direct evidence of the competition for

Subjective perception of radioactivity. No change post successful treatment with radioiodine

International Nuclear Information System (INIS)

Freudenberg, L.S.; Mueller, S.P.; Beyer, T.; Bockisch, A.

2009-01-01

We assess the attitude of patients with thyroid disease towards radiation and radioactivity before and after radioiodine therapy by means of a cultural-anthropological approach. We evaluate in patient interviews how their subjective attitude towards radioactivity as an abstract term and towards radioactivity in the medical context on the basis of their personal experiences with radionuclide therapy. 29 patients with autonomously functioning thyroid lesions (17 women, 12 men, 35-79 years) were included in this study. All patients were interviewed prior to and 22-27 month post radioiodine therapy in an open dialogue with the principal investigator. Patients were asked to describe their attitude towards radioactivity in general and towards radioiodine therapy in particular. Patients were asked to use a scoring system (1: positive, 5: negative) to quantify their perception of radioactivity. The personal perception of radioactivity as an abstract term does not change significantly (p = 0.15) before and after radioiodine therapy. This perception is linked to mostly negative impressions of radiactivity. However, patients become more positive when assessing the value of radioactivity as part of their therapy regimen. Thus, we observe a significant increase in percepted value of radioactivity post radioiodine therapy (p = 0.03). Patients continue to view radioactivity as something negative despite treatment success following radioiodine therapy. Our results provide useful information for patient information by the nuclear medicine physician prior to a radioiodine therapy. (orig.)

A global vertical reference frame based on four regional vertical datums

Czech Academy of Sciences Publication Activity Database

Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vojtíšková, M.

2004-01-01

Roč. 48, č. 3 (2004), s. 493-502 ISSN 0039-3169 Institutional research plan: CEZ:AV0Z1003909 Keywords : geopotentinal * local vertical datums * global vertical reference frame Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.447, year: 2004

Perceived direction of gravity and the body-axis during static whole body roll-tilt in healthy subjects.

Science.gov (United States)

Tamura, Atsushi; Wada, Yoshiro; Inui, Takuo; Shiotani, Akihiro

2017-10-01

We used the subjective visual vertical (SVV) and two different subjective visual body axis (SVBA) methods to quantify roll-tilt perception under gravity, and investigated the characteristics of these methods during static roll-tilt. In addition, we independently developed a compact device to facilitate evaluation of SVBA in different gravitational environments. Ten male volunteers participated in this study. We created a roll-tilt environment using a flight simulator in a dark room. The cockpit of the simulator was tilted leftward or rightward (-30°, -20°, -10°, 0°, 10°, 20° and 30°) in each randomly ordered trial. We quantified roll-tilt perception such that the experiment was conducted under 21 different conditions per participant. We found no significant differences among the SVV error and the two types of SVBA error. The SVV and the SVBA methods may be useful for evaluating subjective roll-tilt perception.

Global Vertical Reference Frame

Czech Academy of Sciences Publication Activity Database

Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vojtíšková, M.

2004-01-01

Roč. 33, - (2004), s. 404-407 ISSN 1436-3445 Institutional research plan: CEZ:AV0Z1003909 Keywords : geopotential WO * vertical systems * global vertical frame Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

Ambiguity in Tactile Apparent Motion Perception.

Directory of Open Access Journals (Sweden)

Emanuela Liaci

Full Text Available In von Schiller's Stroboscopic Alternative Motion (SAM stimulus two visually presented diagonal dot pairs, located on the corners of an imaginary rectangle, alternate with each other and induce either horizontal, vertical or, rarely, rotational motion percepts. SAM motion perception can be described by a psychometric function of the dot aspect ratio ("AR", i.e. the relation between vertical and horizontal dot distances. Further, with equal horizontal and vertical dot distances (AR = 1 perception is biased towards vertical motion. In a series of five experiments, we presented tactile SAM versions and studied the role of AR and of different reference frames for the perception of tactile apparent motion.We presented tactile SAM stimuli and varied the ARs, while participants reported the perceived motion directions. Pairs of vibration stimulators were attached to the participants' forearms and stimulator distances were varied within and between forearms. We compared straight and rotated forearm conditions with each other in order to disentangle the roles of exogenous and endogenous reference frames.Increasing the tactile SAM's AR biased perception towards vertical motion, but the effect was weak compared to the visual modality. We found no horizontal disambiguation, even for very small tactile ARs. A forearm rotation by 90° kept the vertical bias, even though it was now coupled with small ARs. A 45° rotation condition with crossed forearms, however, evoked a strong horizontal motion bias.Existing approaches to explain the visual SAM bias fail to explain the current tactile results. Particularly puzzling is the strong horizontal bias in the crossed-forearm conditions. In the case of tactile apparent motion, there seem to be no fixed priority rule for perceptual disambiguation. Rather the weighting of available evidence seems to depend on the degree of stimulus ambiguity, the current situation and on the perceptual strategy of the individual

Transfer of learned perception of sensorimotor simultaneity.

Science.gov (United States)

Pesavento, Michael J; Schlag, John

2006-10-01

Synchronizing a motor response to a predictable sensory stimulus, like a periodic flash or click, relies on feedback (somesthetic, auditory, visual, or other) from the motor response. Practically, this results in a small (<50 ms) asynchrony in which the motor response leads the sensory event. Here we show that the perceived simultaneity in a coincidence-anticipation task (line crossing) is affected by changing the perceived simultaneity in a different task (pacing). In the pace task, human subjects were instructed to press a key in perfect synchrony with a red square flashed every second. In training sessions, feedback was provided by flashing a blue square with each key press, below the red square. There were two types of training pace sessions: one in which the feedback was provided with no delay, the other (adapting), in which the feedback was progressively delayed (up to 100 ms). Subjects' asynchrony was unchanged in the first case, but it was significantly increased in the pace task with delay. In the coincidence-anticipation task, a horizontally moving vertical bar crossed a vertical line in the middle of a screen. Subjects were instructed to press a key exactly when the bar crossed the line. They were given no feedback on their performance. Asynchrony on the line-crossing task was tested after the training pace task with feedback. We found that this asynchrony to be significantly increased even though there never was any feedback on the coincidence-anticipation task itself. Subjects were not aware that their sensorimotor asynchrony had been lengthened (sometimes doubled). We conclude that perception of simultaneity in a sensorimotor task is learned. If this perception is caused by coincidence of signals in the brain, the timing of these signals depends on something-acquired by experience-more adaptable than physiological latencies.

The Influence of Gender, Grade Level and Favourite Subject on Czech Lower Secondary School Pupils' Perception of Geography

Science.gov (United States)

Kubiatko, Milan; Janko, Tomas; Mrazkova, Katerina

2012-01-01

Geography is an important school subject that brings pupils' description and explanation of social, economic and/or political aspects of the changing world. It has been affirmed that the interest in a subject depends on the attitude to this subject. This study investigates Czech lower secondary school pupils' perception of geography. The research…

The impact of cochlear implantation on speech understanding, subjective hearing performance, and tinnitus perception in patients with unilateral severe to profound hearing loss.

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Távora-Vieira, Dayse; Marino, Roberta; Acharya, Aanand; Rajan, Gunesh P

2015-03-01

This study aimed to determine the impact of cochlear implantation on speech understanding in noise, subjective perception of hearing, and tinnitus perception of adult patients with unilateral severe to profound hearing loss and to investigate whether duration of deafness and age at implantation would influence the outcomes. In addition, this article describes the auditory training protocol used for unilaterally deaf patients. This is a prospective study of subjects undergoing cochlear implantation for unilateral deafness with or without associated tinnitus. Speech perception in noise was tested using the Bamford-Kowal-Bench speech-in-noise test presented at 65 dB SPL. The Speech, Spatial, and Qualities of Hearing Scale and the Abbreviated Profile of Hearing Aid Benefit were used to evaluate the subjective perception of hearing with a cochlear implant and quality of life. Tinnitus disturbance was measured using the Tinnitus Reaction Questionnaire. Data were collected before cochlear implantation and 3, 6, 12, and 24 months after implantation. Twenty-eight postlingual unilaterally deaf adults with or without tinnitus were implanted. There was a significant improvement in speech perception in noise across time in all spatial configurations. There was an overall significant improvement on the subjective perception of hearing and quality of life. Tinnitus disturbance reduced significantly across time. Age at implantation and duration of deafness did not influence the outcomes significantly. Cochlear implantation provided significant improvement in speech understanding in challenging situations, subjective perception of hearing performance, and quality of life. Cochlear implantation also resulted in reduced tinnitus disturbance. Age at implantation and duration of deafness did not seem to influence the outcomes.

Subjective perception of sleep benefit in Parkinson's disease: Valid or irrelevant?

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Lee, Will; Evans, Andrew; Williams, David R

2017-09-01

The phenomenon of sleep benefit (SB) in Parkinson's disease (PD), whereby waking motor function is improved despite no dopaminergic treatment overnight, is controversial. Previous studies suggested a significant discrepancy between subjective functional and objective motor improvement. The aim of this study was to determine how well subjective reporting of SB correlates with objective measures and if true motor improvement can be predicted by a standardized questionnaire. Ninety-two patients with PD participated. A structured questionnaire was developed to assess subjective SB. Quantitative motor assessment was performed using a validated smartphone application. Objective motor SB was considered to be present when the waking motor function was similar or superior to the daytime on-state. Twenty (22%) patients showed objective motor improvement on waking compared to end-of-dose. Most patients (77%) reported subjective SB without corresponding objective motor benefit. Our structured questionnaire could not predict Motor SB. The ability to delay morning medications and a perception of indifference or paradoxical worsening following the morning levodopa dose may suggest Motor SB. Most patients experience subjective SB with no measureable motor improvement. This perceived benefit could be related to non-motor improvement that is distinctly different to objective motor benefit. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gravity dependence of the effect of optokinetic stimulation on the subjective visual vertical.

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Ward, Bryan K; Bockisch, Christopher J; Caramia, Nicoletta; Bertolini, Giovanni; Tarnutzer, Alexander Andrea

2017-05-01

Accurate and precise estimates of direction of gravity are essential for spatial orientation. According to Bayesian theory, multisensory vestibular, visual, and proprioceptive input is centrally integrated in a weighted fashion based on the reliability of the component sensory signals. For otolithic input, a decreasing signal-to-noise ratio was demonstrated with increasing roll angle. We hypothesized that the weights of vestibular (otolithic) and extravestibular (visual/proprioceptive) sensors are roll-angle dependent and predicted an increased weight of extravestibular cues with increasing roll angle, potentially following the Bayesian hypothesis. To probe this concept, the subjective visual vertical (SVV) was assessed in different roll positions (≤ ± 120°, steps = 30°, n = 10) with/without presenting an optokinetic stimulus (velocity = ± 60°/s). The optokinetic stimulus biased the SVV toward the direction of stimulus rotation for roll angles ≥ ± 30° ( P stimulation. Variability and optokinetic bias were correlated ( R 2 = 0.71, slope = 0.71, 95% confidence interval = 0.57-0.86). An optimal-observer model combining an optokinetic bias with vestibular input reproduced measured errors closely. These findings support the hypothesis of a weighted multisensory integration when estimating direction of gravity with optokinetic stimulation. Visual input was weighted more when vestibular input became less reliable, i.e., at larger roll-tilt angles. However, according to Bayesian theory, the variability of combined cues is always lower than the variability of each source cue. If the observed increase in variability, although nonsignificant, is true, either it must depend on an additional source of variability, added after SVV computation, or it would conflict with the Bayesian hypothesis. NEW & NOTEWORTHY Applying a rotating optokinetic stimulus while recording the subjective visual vertical in different whole body roll angles, we noted the optokinetic

Geometrical factors in the perception of sacredness

DEFF Research Database (Denmark)

Costa, Marco; Bonetti, Leonardo

2016-01-01

Geometrical and environmental factors in the perception of sacredness, dominance, and attractiveness were assessed by 137 participants in five tests. In the first test, a two-alternative forced-choice paradigm was used to test the perception of sacredness, dominance, and attractiveness in geometr......Geometrical and environmental factors in the perception of sacredness, dominance, and attractiveness were assessed by 137 participants in five tests. In the first test, a two-alternative forced-choice paradigm was used to test the perception of sacredness, dominance, and attractiveness...... in geometrical figures differing in shape, verticality, size, and symmetry. Verticality, symmetry, and convexity were found to be important factors in the perception of sacredness. In the second test, participants had to mark the point inside geometrical surfaces that was perceived as most sacred, dominant....... Geometrical factors in the perception of sacredness, dominance, and attractiveness were largely overlapping....

[The influence of musical rhythms on the perception of subjective states of adult patients on dialysis].

Science.gov (United States)

Caminha, Leandro Bechert; da Silva, Maria Júlia Paes; Leão, Eliseth Ribeiro

2009-12-01

Being submitted to dialysis four hours a day, three times a week can mean experiencing boredom, besides discomfort. Patients often report that the time seems to take longer to go by. The purpose of this study was to explore the influence of two different musical rhythms in the states of mind and perception of adult patients undergoing dialysis, since the literature on this subject is scarce. The study was performed at a private hospital with 43 patients, who participated in two sessions of musical improvisation with a keyboard. The subjective states and perception were evaluated before and after the intervention. Over 80% of the patients felt that time went by faster after the interventions in both rhythms. However, the pace was a decisive factor in the kind of emotional experience that the patients had.

Diafragmas horizontais de piso em madeira, confeccionados com chapas de OSB e vigas I, submetido ao carregamento vertical = Wood light-frame floor diaphragms, made with OSB panels and Ijoists, subjected to vertical loads

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Altevir Castro dos Santos

2007-07-01

Full Text Available Este trabalho aborda construções em madeira sob a ótica de sistemas com estruturas leves; apresenta análise computacional por meio de modelagem pelo método de elementos finitos de diafragmas de piso e vigas I, submetidas a ensaio de flexão a quatro pontos. O objetivo geral é avaliar a resistência e a rigidez de diafragmas horizontais,construídos em Sistemas Leves de Madeira, quando submetidos a ações verticais. As análises foram realizadas por meio do programa computacional SAP2000 e foram avaliadas as influências dos seguintes parâmetros: espaçamento entre vigas que constituem os elementosde ossatura do diafragma horizontal e o espaçamento entre pregos de fixação do contrapiso, composto por chapas de OSB – Oriented Strand Board. Ao final do trabalho, comparam-se os resultados obtidos a partir das análises numérica e teórica, e são apresentadas algumasconclusões.Wood light-frame floor diaphragms, made with OSB panels and I-joists, subjected to vertical loads. This work is focused on lightweight woodframe constructions, and presents a finite element modeling of floor diaphragms and wood I-joists subjected to four-point bending. It presents the results of experimental tests on wood I-joists subjected to vertical loads. The main goal of this research is to evaluate the resistance and rigidity of wood light-frame floor diaphragms, when subjected to monotonic vertical forces acting in the plane of the floor. The analyses were performed using the SAP2000 computer program and tested with diferent constructive arrangements, and the influence of the following variables were examined: distance between wood I-joists, and distance between nails around the perimeter of the OSB boards. Finally, a comparison between analytical and numerical results is performed.

The radiation and variable viscosity effects on electrically conducting fluid over a vertically moving plate subjected to suction and heat flux

Energy Technology Data Exchange (ETDEWEB)

Malekzadeh, P., E-mail: malekzadeh@pgu.ac.i [Department of Mechanical Engineering, Persian Gulf University, Bushehr 75168 (Iran, Islamic Republic of); Center of Excellence for Computational Mechanics, Shiraz University, Shiraz (Iran, Islamic Republic of); Moghimi, M.A. [Department of Mechanical Engineering, School of Engineering, Shaid Bahonar University, Kerman (Iran, Islamic Republic of); Nickaeen, M. [K.N. Toosi University of Technology, Tehran (Iran, Islamic Republic of)

2011-05-15

Research highlights: {yields} A new application of the differential quadrature method in thermo-fluid fields. {yields} Moving vertical plate with suction and heat flux is considered. {yields} Fluid with variable viscosity subjected to thermal radiation is studied. -- Abstract: In this paper, firstly, the applicability of the differential quadrature method (DQM) as an efficient and accurate numerical method for solving the problem of variable viscosity and thermally radiative unsteady magneto-hydrodynamic (MHD) flow over a moving vertical plate with suction and heat flux is investigated. The spatial as well as the temporal domains are discretized using the DQM. The fast rate of convergence of the method is demonstrated and for the cases that a solution is available, comparison is done. Then, effects of the temperature dependence of viscosity and different fluid parameters on the velocity and temperature of transient MHD flow subjected to the above mentioned boundary condition are studied.

Perception of social interaction compresses subjective duration in an oxytocin-dependent manner.

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Liu, Rui; Yuan, Xiangyong; Chen, Kepu; Jiang, Yi; Zhou, Wen

2018-05-22

Communication through body gestures permeates our daily life. Efficient perception of the message therein reflects one's social cognitive competency. Here we report that such competency is manifested temporally as shortened subjective duration of social interactions: motion sequences showing agents acting communicatively are perceived to be significantly shorter in duration as compared with those acting noncommunicatively. The strength of this effect is negatively correlated with one's autistic-like tendency. Critically, intranasal oxytocin administration restores the temporal compression effect in socially less proficient individuals, whereas the administration of atosiban, a competitive antagonist of oxytocin, diminishes the effect in socially proficient individuals. These findings indicate that perceived time, rather than being a faithful representation of physical time, is highly idiosyncratic and ingrained with one's personality trait. Moreover, they suggest that oxytocin is involved in mediating time perception of social interaction, further supporting the role of oxytocin in human social cognition. © 2018, Liu et al.

Perception of risk and subjective health among victims of the Chernobyl disaster.

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Havenaar, J M; de Wilde, E J; van den Bout, J; Drottz-Sjöberg, B M; van den Brink, W

2003-02-01

Several studies have demonstrated that the nuclear power plant accident at Chernobyl in 1986 had a strong impact on the subjective health of the inhabitants in the surrounding regions and that the majority of these health complaints appear to be stress-related. An epidemiological survey among the adult population of the Gomel region in Belarus near Chernobyl showed higher rates of self-reported health problems, psychological distress and medical service use in this region than in a comparable unexposed region. This paper presents an analysis of data on cognitive factors that were collected in this study. The findings support the hypothesis that cognitive variables such as risk perception and sense of control play an important role as mediating factors in the explanation of the observed health differences between the exposed and non-exposed regions. A tentative model is presented to further clarify the role of risk perception in the occurrence of non-specific health complaints after such ecological disasters.

Developing Buoyancy Driven Flow of a Nanofluid in a Vertical Channel Subject to Heat Flux

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Nirmal C. Sacheti

2014-01-01

Full Text Available The developing natural convective flow of a nanofluid in an infinite vertical channel with impermeable bounding walls has been investigated. It is assumed that the nanofluid is dominated by two specific slip mechanisms and that the channel walls are subject to constant heat flux and isothermal temperature, respectively. The governing nonlinear partial differential equations coupling different transport processes have been solved numerically. The variations of velocity, temperature, and nanoparticles concentration have been discussed in relation to a number of physical parameters. It is seen that the approach to the steady-state profiles of velocity and temperature in the present work is different from the ones reported in a previous study corresponding to isothermal wall conditions.

Assessing verticalization effects on urban safety perception

OpenAIRE

Lourenço, Ricardo Barros

2017-01-01

We describe an experiment with the modeling of urban verticalization effects on perceived safety scores as obtained with computer vision on Google Streetview data for New York City. Preliminary results suggests that for smaller buildings (between one and seven floors), perceived safety increases with building height, but that for high-rise buildings, perceived safety decreases with increased height. We also determined that while height contributing for this relation, other zonal aspects also ...

Association between subjective risk perception and objective risk estimation in patients with atrial fibrillation: a cross-sectional study.

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Zweiker, David; Zweiker, Robert; Winkler, Elisabeth; Roesch, Konstantina; Schumacher, Martin; Stepan, Vinzenz; Krippl, Peter; Bauer, Norbert; Heine, Martin; Reicht, Gerhard; Zweiker, Gudrun; Sprenger, Martin; Watzinger, Norbert

2017-09-25

Oral anticoagulation (OAC) is state-of-the-art therapy for atrial fibrillation (AF), the most common arrhythmia worldwide. However, little is known about the perception of patients with AF and how it correlates with risk scores used by their physicians. Therefore, we correlated patients' estimates of their own stroke and bleeding risk with the objectively predicted individual risk using CHA 2 DS 2 -VASc and HAS-BLED scores. Cross-sectional prevalence study using convenience sampling and telephone follow-up. Eight hospital departments and one general practitioner in Austria. Patients' perception of stroke and bleeding risk was opposed to commonly used risk scoring. Patients with newly diagnosed AF and indication for anticoagulation. Comparison of subjective risk perception with CHA 2 DS 2 -VASc and HAS-BLED scores showing possible discrepancies between subjective and objective risk estimation. Patients' judgement of their own knowledge on AF and education were also correlated with accuracy of subjective risk appraisal. Ninety-one patients (age 73±11 years, 45% female) were included in this study. Subjective stroke and bleeding risk estimation did not correlate with risk scores (ρ=0.08 and ρ=0.17). The majority of patients (57%) underestimated the individual stroke risk. Patients feared stroke more than bleeding (67% vs 10%). There was no relationship between accurate perception of stroke and bleeding risks and education level. However, we found a correlation between the patients' judgement of their own knowledge of AF and correct assessment of individual stroke risk (ρ=0.24, p=0.02). During follow-up, patients experienced the following events: death (n=5), stroke (n=2), bleeding (n=1). OAC discontinuation rate despite indication was 3%. In this cross-sectional analysis of OAC-naive patients with AF, we found major differences between patients' perceptions and physicians' assessments of risks and benefits of OAC. To ensure shared decision-making and informed

Objective correlate of subjective pain perception by contact heat-evoked potentials.

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Granovsky, Yelena; Granot, Michal; Nir, Rony-Reuven; Yarnitsky, David

2008-01-01

The method of pain-evoked potentials has gained considerable acceptance over the last 3 decades regarding its objectivity, repeatability, and quantifiability. The present study explored whether the relationship between pain-evoked potentials and pain psychophysics obtained by contact heat stimuli is similar to those observed for the conventionally used laser stimulation. Evoked potentials (EPs) were recorded in response to contact heat stimuli at different body sites in 24 healthy volunteers. Stimuli at various temperatures were applied to the forearm (43 degrees C, 46 degrees C, 49 degrees C, and 52 degrees C) and leg (46 degrees C and 49 degrees C). The amplitudes of both components (N2 and P2) were strongly associated with the intensity of the applied stimuli and with subjective pain perception. Yet, regression analysis revealed pain perception and not stimulus intensity as the major contributing factor. A significant correlation was found between the forearm and the leg for both psychophysics and EPs amplitude. Contact heat can generate readily distinguishable evoked potentials on the scalp, consistent between upper and lower limbs. Although these potentials bear positive correlation with both stimulus intensity and pain magnitude, the latter is the main contributor to the evoked brain response.

Measuring Pictorial Balance Perception at First Glance using Japanese Calligraphy

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Sharon Gershoni

2011-08-01

Full Text Available According to art theory, pictorial balance acts to unify picture elements into a cohesive composition. For asymmetrical compositions, balancing elements is thought to be similar to balancing mechanical weights in a framework of symmetry axes. Assessment of preference for balance (APB, based on the symmetry-axes framework suggested in Arnheim R, 1974 Art and Visual Perception: A Psychology of the Creative Eye (Berkeley, CA: University of California Press, successfully matched subject balance ratings of images of geometrical shapes over unlimited viewing time. We now examine pictorial balance perception of Japanese calligraphy during first fixation, isolated from later cognitive processes, comparing APB measures with results from balance-rating and comparison tasks. Results show high between-task correlation, but low correlation with APB. We repeated the rating task, expanding the image set to include five rotations of each image, comparing balance perception of artist and novice participant groups. Rotation has no effect on APB balance computation but dramatically affects balance rating, especially for art experts. We analyze the variety of rotation effects and suggest that, rather than depending on element size and position relative to symmetry axes, first fixation balance processing derives from global processes such as grouping of lines and shapes, object recognition, preference for horizontal and vertical elements, closure, and completion, enhanced by vertical symmetry.

Visiting Richard Serra’s Promenade sculpture improves postural control and judgment of subjective visual vertical.

Directory of Open Access Journals (Sweden)

Zoï eKapoula

2014-12-01

Full Text Available Body sway while maintaining an upright quiet stance reflects an active process of balance based on the integration of visual, vestibular, somatosensory and proprioceptive inputs. Richard Serra’s Promenade sculpture featured in the 2008 Monumenta exhibition at the Grand Palais in Paris, France is herein hypothesised to have stimulated the body’s vertical and longitudinal axes as it showcased 5 monumental rectangular solids pitched at a 1.69° angle.Using computerised dynamic posturography we measured the body sway of 23 visitors when fixating a cross, or when observing the artwork (fixating it or actively exploring it with eye movements before and after walking around and alongside the sculpture (i.e., before and after a promenade. A first fixation at the sculpture increased medio-lateral stability (in terms of spectral power of body sway. Eye movement exploration in the depth of the sculpture increased antero-posterior stability (in terms of spectral power and cancelling time of body sway at the expense of medio-lateral stability (in terms of cancelling time. Moreover, a medio-lateral instability associated with eye movement exploration before the promenade (in terms of body sway sensu stricto was cancelled after the promenade. Finally, the overall medio-lateral stability (in terms of spectral power increased after the promenade.Fourteen additional visitors were asked to sit in a dark room and adjust a luminous line to what they considered to be the earth-vertical axis. The promenade executed within the sculpted environment afforded by Serra’s monumental statuary works resulted in significantly improved performances on the subjective visual vertical test.We attribute these effects to the sculpted environment provided by the exhibition which may have acted as a kind of physiologic training ground thereby improving the visitors’ overall sense of visual perspective, equilibrium and gravity.

Perceptions of disease risk: from social construction of subjective judgments to rational decision making.

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McRoberts, N; Hall, C; Madden, L V; Hughes, G

2011-06-01

Many factors influence how people form risk perceptions. Farmers' perceptions of risk and levels of risk aversion impact on decision-making about such things as technology adoption and disease management practices. Irrespective of the underlying factors that affect risk perceptions, those perceptions can be summarized by variables capturing impact and uncertainty components of risk. We discuss a new framework that has the subjective probability of disease and the cost of decision errors as its central features, which might allow a better integration of social science and epidemiology, to the benefit of plant disease management. By focusing on the probability and cost (or impact) dimensions of risk, the framework integrates research from the social sciences, economics, decision theory, and epidemiology. In particular, we review some useful properties of expected regret and skill value, two measures of expected cost that are particularly useful in the evaluation of decision tools. We highlight decision-theoretic constraints on the usefulness of decision tools that may partly explain cases of failure of adoption. We extend this analysis by considering information-theoretic criteria that link model complexity and relative performance and which might explain why users reject forecasters that impose even moderate increases in the complexity of decision making despite improvements in performance or accept very simple decision tools that have relatively poor performance.

Perception of self motion during and after passive rotation of the body around an earth-vertical axis.

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Sinha, N; Zaher, N; Shaikh, A G; Lasker, A G; Zee, D S; Tarnutzer, A A

2008-01-01

We investigated the perception of self-rotation using constant-velocity chair rotations. Subjects signalled self motion during three independent tasks (1) by pushing a button when rotation was first sensed, when velocity reached a peak, when velocity began to decrease, and when velocity reached zero, (2) by rotating a disc to match the perceived motion of the body, or (3) by changing the static position of the dial such that a bigger change in its position correlated with a larger perceived velocity. All three tasks gave a consistent quantitative measure of perceived angular velocity. We found a delay in the time at which peak velocity of self-rotation was perceived (2-5 s) relative to the beginning or to the end of chair rotation. In addition the decay of the perception of self-rotation was preceded by a sensed constant-velocity interval or plateau (9-14 s). This delay in the rise of self-motion perception, and the plateau for the maximum perceived velocity, contrasts with the rapid rise and the immediate decay of the angular vestibuloocular reflex (aVOR). This difference suggests that the sensory signal from the semicircular canals undergoes additional neural processing, beyond the contribution of the velocity-storage mechanism of the aVOR, to compute the percept of self-motion.

[Objective assessment of disorders of visual perception following unilateral vestibular loss. Studies of the so-called Dandy symptom].

Science.gov (United States)

Stoll, W; Werner, F; Kauffmann, G

1991-02-01

Visual ability and compensatory eye movements during defined vertical oscillation were investigated in 20 patients with unilateral lesions of labyrinthine function and in 20 normal subjects. Oscillation frequencies were performed at the rate of 1 to 1.5 Hz with an amplitude of 5 cm, comparative to head locomotions of a running person. In synchronism with this, the visual function was tested with Landolt rings. Patients complaining of subjective visual disturbance during walking and running, also presented a measurable blur of vision under test conditions. In addition, eye movements were recorded and classified into three types. However, these eye movements showed no relation to gaze function. Our results suggest that the otolith-ocular reflex may participate in adjusting the vertical eye position during vertical stimulations at low frequencies. The effect of visual disturbances in patients with labyrinthine lesions is explained by the "efference-copy" initially described by von Holst. The efference-copy is responsible for the neutralisation of provoked retinal perceptions.

Estimating Vertical Stress on Soil Subjected to Vehicular Loading

Science.gov (United States)

2009-02-01

specified surface area of the tire . The silt and sand samples were both estimated to be 23.7-in. thick over a base of much harder soil. The pressures...study in which highway tread tires were used as opposed to the all-terrain tread currently on the vehicle. If the pressure pads are functioning...Vertical force versus time (front right CIV tire )....................................................................... 14 Tables Table 1. Testing

Within-subjects comparison of the HiRes and Fidelity120 speech processing strategies: speech perception and its relation to place-pitch sensitivity.

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Donaldson, Gail S; Dawson, Patricia K; Borden, Lamar Z

2011-01-01

Previous studies have confirmed that current steering can increase the number of discriminable pitches available to many cochlear implant (CI) users; however, the ability to perceive additional pitches has not been linked to improved speech perception. The primary goals of this study were to determine (1) whether adult CI users can achieve higher levels of spectral cue transmission with a speech processing strategy that implements current steering (Fidelity120) than with a predecessor strategy (HiRes) and, if so, (2) whether the magnitude of improvement can be predicted from individual differences in place-pitch sensitivity. A secondary goal was to determine whether Fidelity120 supports higher levels of speech recognition in noise than HiRes. A within-subjects repeated measures design evaluated speech perception performance with Fidelity120 relative to HiRes in 10 adult CI users. Subjects used the novel strategy (either HiRes or Fidelity120) for 8 wks during the main study; a subset of five subjects used Fidelity120 for three additional months after the main study. Speech perception was assessed for the spectral cues related to vowel F1 frequency, vowel F2 frequency, and consonant place of articulation; overall transmitted information for vowels and consonants; and sentence recognition in noise. Place-pitch sensitivity was measured for electrode pairs in the apical, middle, and basal regions of the implanted array using a psychophysical pitch-ranking task. With one exception, there was no effect of strategy (HiRes versus Fidelity120) on the speech measures tested, either during the main study (N = 10) or after extended use of Fidelity120 (N = 5). The exception was a small but significant advantage for HiRes over Fidelity120 for consonant perception during the main study. Examination of individual subjects' data revealed that 3 of 10 subjects demonstrated improved perception of one or more spectral cues with Fidelity120 relative to HiRes after 8 wks or longer

Learning with LinkedIn: Students' Perceptions of Incorporating Subject-Related Blogging in an International Marketing Course

Science.gov (United States)

Galan, Nataliya; Khodabandehloo, Akbar

2016-01-01

Purpose: This paper aims to report the results of implementation of blogging within a LinkedIn discussion group in an international marketing course for a multicultural group of students focusing on the students' perceptions of the subject-related blogging. Design/Methodology/ Approach: This study adopts a qualitative approach; data have been…

Evaluation of sealing performance of metal cask subjected to vertical impact load due to aircraft engine

International Nuclear Information System (INIS)

Namba, Kosuke; Shirai, Koji; Saegusa, Toshiari

2010-01-01

To confirm the sealing performance of a metal cask subjected to impact force due to commercial aircraft crash against a spent fuel storage facility, a vertical impact test was carried out. In this test, a simplified deformable missile was used by considering the rigidity of the actual aircraft engine and accelerated to the specified impact velocity (60 m/s) to hit the full-scale lid structure with the primary and secondary lids. Then, the leak rate, the inner pressure between the lids, and the displacement of the lids were measured. The leak rate of the secondary lid exceeded 1.0x10 -3 Pa·m 3 /s upon impact. However, because no residual lid opening displacement occurred after loading, the leak rate recovered to less than 1.0x10 -6 Pa·m 3 /s after 3 h from the impact test. In addition, to clarify the impact behaviour of the lid structure, the impact analysis using the LS-DYNA code was executed. It was found that the lid bolts maintained the good tightening force after impact loading, and the sealing performance of the full-scale metal cask would not be affected immediately by the vertical impact of the aircraft engine with a speed of 60 m/s. (author)

Association of a trait-like bias towards the perception of negative subjective life events with risk of developing premenstrual symptoms.

Science.gov (United States)

Gonda, Xenia; Fountoulakis, Konstantinos N; Csukly, Gabor; Telek, Tamas; Pap, Dorottya; Rihmer, Zoltan; Bagdy, Gyorgy

2010-04-16

Premenstrual symptoms affect the majority of healthy women. Premenstrual symptomatology has earlier been linked to stress and a state-like alteration in the perception of life events in the late-luteal phase of the menstrual cycle. We hypothesised that there is also a trait-like negative bias in the perception of life events evident throughout the whole cycle which is associated with the likelihood to manifest more marked symptoms in the late-luteal phase of the cycle. 88 healthy women completed the PRISM calendar for three consecutive cycles and the Objective and Subjective Event Checklist during the follicular phase of the first cycle. Association between PRISM score change from the follicular through the late-luteal phase and life event variables was investigated by Generalized Linear Model Analysis (GENMOD). The PRISM score change showed a significant negative association with the ratio of positive subjective life events and a significant positive association with the ratio of negative subjective life events. There were no significant results in case of the objective life events. Our results indicate that women manifesting a more marked increase of symptoms from the late follicular through the late-luteal phase of the menstrual cycle are more likely to notice negative subjective life events and less likely to notice positive subjective life events. This suggest a trait-like negative bias in the perception of life events present throughout the whole reproductive cycle which may play an important role in the emergence of premenstrual symptoms. Copyright 2010 Elsevier Inc. All rights reserved.

Intranasal Oxytocin Selectively Modulates Social Perception, Craving, and Approach Behavior in Subjects With Alcohol Use Disorder.

Science.gov (United States)

Mitchell, Jennifer M; Arcuni, Peter A; Weinstein, Dawn; Woolley, Josh D

2016-01-01

A pharmacotherapy that both improves social abilities and promotes abstinence may be particularly helpful for the treatment of alcohol use disorder. Recent clinical and preclinical evidence suggests that oxytocin has prosocial and antiaddiction effects. We performed a pilot, laboratory-based, preclinical trial of oxytocin in subjects with alcohol abuse (as per Diagnostic and Statistical Manual of Mental Disorders, 4 Edition criteria) to evaluate therapeutic potential and assess tolerability. Social perceptual ability, cue-induced craving, and approach bias for alcohol and appetitive imagery were quantified after intranasal oxytocin and placebo administration to 32 nontreatment-seeking individuals with alcohol abuse in a double-blind, crossover study. Because attachment style can moderate the effects of oxytocin, we also explored whether attachment style moderated oxytocin's effects on our behavioral measures. Oxytocin significantly improved recognition of easier items on a social perception task, but had no significant group-level effect on cue-induced craving. However, oxytocin effects on craving were moderated by attachment anxiety, with oxytocin reducing craving in more anxiously attached individuals and increasing craving in less anxiously attached individuals. Subjects did not display an approach bias to alcohol images on the placebo day, preventing meaningful analysis of this measure. Subjects did display an approach bias to appetitive images on the placebo day, which was significantly reduced by oxytocin administration. No adverse reactions were observed. Intranasal oxytocin has potential to improve social perception, reduce cue-induced alcohol cravings, and reduce appetitive approach bias in subjects with alcohol abuse, and can be safely tolerated in this population. The effects of oxytocin are complex, however, and require further investigation.

Spatial judgments in the horizontal and vertical planes from different vantage points.

Science.gov (United States)

Prytz, Erik; Scerbo, Mark W

2012-01-01

Todorović (2008 Perception 37 106-125) reported that there are systematic errors in the perception of 3-D space when viewing 2-D linear perspective drawings depending on the observer's vantage point. Because these findings were restricted to the horizontal plane, the current study was designed to determine the nature of these errors in the vertical plane. Participants viewed an image containing multiple colonnades aligned on parallel converging lines receding to a vanishing point. They were asked to judge where, in the physical room, the next column should be placed. The results support Todorović in that systematic deviations in the spatial judgments depended on vantage point for both the horizontal and vertical planes. However, there are also marked differences between the two planes. While judgments in both planes failed to compensate adequately for the vantage-point shift, the vertical plane induced greater distortions of the stimulus image itself within each vantage point.

Balancing bistable perception during self-motion.

Science.gov (United States)

van Elk, Michiel; Blanke, Olaf

2012-10-01

In two experiments we investigated whether bistable visual perception is influenced by passive own body displacements due to vestibular stimulation. For this we passively rotated our participants around the vertical (yaw) axis while observing different rotating bistable stimuli (bodily or non-bodily) with different ambiguous motion directions. Based on previous work on multimodal effects on bistable perception, we hypothesized that vestibular stimulation should alter bistable perception and that the effects should differ for bodily versus non-bodily stimuli. In the first experiment, it was found that the rotation bias (i.e., the difference between the percentage of time that a CW or CCW rotation was perceived) was selectively modulated by vestibular stimulation: the perceived duration of the bodily stimuli was longer for the rotation direction congruent with the subject's own body rotation, whereas the opposite was true for the non-bodily stimulus (Necker cube). The results found in the second experiment extend the findings from the first experiment and show that these vestibular effects on bistable perception only occur when the axis of rotation of the bodily stimulus matches the axis of passive own body rotation. These findings indicate that the effect of vestibular stimulation on the rotation bias depends on the stimulus that is presented and the rotation axis of the stimulus. Although most studies on vestibular processing have traditionally focused on multisensory signal integration for posture, balance, and heading direction, the present data show that vestibular self-motion influences the perception of bistable bodily stimuli revealing the importance of vestibular mechanisms for visual consciousness.

Influence of the vertical position of maxillary central incisors on the perception of smile esthetics among orthodontists and laypersons.

Science.gov (United States)

Machado, Andre Wilson; McComb, Ryan W; Moon, Won; Gandini, Luiz Gonzaga

2013-12-01

The purpose of this study was to determine the perception of smile esthetics among orthodontists and laypeople with respect to different upper central incisor vertical positions in a frontal smile analysis. A frontal close-up smile photo of an adult Caucasian woman was selected. The patient had healthy upper anterior dentition and had no history of orthodontic treatment. Images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. All images were assessed in three different views: full smile, gingival close-up excluding incisal edges, and incisal close-up excluding gingival margins. Images were randomly assembled in an album, which was given to 120 judges: 60 orthodontists and 60 laypersons. Each rater was asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were then statistically analyzed. The highest rated smiles showed two notable characteristics: the central-to-lateral incisal step was 1.5 mm; and the central incisor gingival margins matched the laterals, and both were 0.5 mm below the line of the canine gingival margins. The least attractive smile was the one with no step between the centrals and laterals, and with the central incisor gingival margins 1.0 mm above the canine gingival margins. The results of this study indicate that slightly extruded upper central incisors are more esthetically preferred than intruded. The upper central incisors are the key determinant in evaluating smile esthetics, and thus, the assessment of their ideal vertical positioning is an aspect of paramount importance. © 2013 Wiley Periodicals, Inc.

Subjective health complaints and illness perception amongst adults with Joint Hypermobility Syndrome/Ehlers-Danlos Syndrome-HypermobilityType - a cross-sectional study.

Science.gov (United States)

Hope, Lena; Juul-Kristensen, Birgit; Løvaas, Helene; Løvvik, Camilla; Maeland, Silje

2017-10-17

To investigate the prevalence and severity of subjective health complaints and describe illness perception in a population of Joint Hypermobility Syndrome or Ehlers-Danlos Syndrome-Hypermobile Type. This study was a postal survey with a questionnaire battery on demographic data, subjective health complaints inventory, and illness perception. A total of 110 individuals diagnosed with Joint Hypermobility Syndrome or Ehlers-Danlos Syndrome-Hypermobile Type from two specialized hospitals in Norway were offered participation. Further, 140 gender- and age-matched healthy controls from statistics Norway representing the general population were sent the questionnaire for reference. Overall response rate was 30.4% (n = 76), with 44.5% (n = 49) in Joint Hypermobility Syndrome/Ehlers-Danlos Syndrome-Hypermobile Type and 19.3% (n = 27) in controls. Subjective health complaints were significantly higher in Joint Hypermobility Syndrome/Ehlers-Danlos Syndrome-Hypermobile Type - than in the controls (32.06 vs. 11.08; p Syndrome/Ehlers-Danlos Syndrome-Hypermobile Type had low understanding of their illness and symptoms (understanding, mean: 3.93, SD 2.88), and reported to have moderate personal and treatment control over their illness. Adults with Joint Hypermobility Syndrome/Ehlers-Danlos Syndrome-Hypermobile Type reported higher frequency and severity of subjective health complaints than the matched controls from the general adult population in Norway. Furthermore, Joint Hypermobility Syndrome/Ehlers-Danlos Syndrome-Hypermobile Type reported low understanding of their illness and associated symptoms, and moderate belief that their illness can be kept under control through self-management or treatment. This may indicate one of the reasons why prognosis for these patients is poor. Implications for rehabilitation Awareness of the complexity of the subjective health complaints and inquiry into illness perception could contribute with valuable information about these

Calculated and perceived cardiovascular risk in asymptomatic subjects submitted to a routine medical evaluation: The perception gap.

Science.gov (United States)

Katz, Marcelo; Laurinavicius, Antonio G; Franco, Fabio G M; Conceicao, Raquel D; Carvalho, Jose A M; Pesaro, Antonio E P; Wajngarten, Mauricio; Santos, Raul D

2015-08-01

Poor adherence to medical treatment represents a major health problem. A subject's misperception of his own cardiovascular risk has been indicated as a key driver for low compliance with preventive measures. This study analysed the relationship between objectively calculated short- and long-term cardiovascular risk and its subjective perception. Cross-sectional study in asymptomatic Brazilian subjects. Individuals (N = 6544, mean age 49.1 ± 7 years, 22.2% female) who underwent a routine mandatory health evaluation were studied. A questionnaire in which each individual rated his own cardiovascular risk as low, intermediate or high according to his own perception was used. The 10-year and lifetime cardiovascular risk were calculated respectively using the Framingham risk (FRS) and Lifetime risk (LRS) scores. Individuals were classified as hypo-perceivers (i.e. perceived risk lower than estimated risk), normo-perceivers (i.e. perceived risk coincident with estimated risk) and hyper-perceivers (i.e. perceived risk higher than estimated risk). Cardiovascular risk, using the FRS, was low in 77.9% (N = 5071), intermediate in 14.4% (N = 939) and high in 7.7% (N = 499) of subjects. Cardiovascular risk, using the LRS, was low in 7.6% (N = 492), intermediate in 43.1% (N = 2787) and high in 49.3% (N = 3184) of the study population. The prevalence of normo-perceivers was 57.6% using the FRS and only 20.6% using the LRS. Using the LRS, 72.3% of the intermediate and 91.2% of the high-risk subjects were hypo-perceivers. In a large sample of asymptomatic individuals, there was a gap between calculated and perceived cardiovascular risk. Using a long-term risk score, most of the intermediate- and high-risk subjects were hypo-perceivers. © The European Society of Cardiology 2014.

Hyperglycaemia attenuates the gastrokinetic effect of erythromycin and affects the perception of postprandial hunger in normal subjects

International Nuclear Information System (INIS)

Jones, K.L.; Berry, M.; Kong, M.F.; Kwiatek, M.; Samsom, M.; Horowitz, M.; Royal Adelaide Hospital, SA

1998-01-01

Full text: Recent studies have demonstrated that acute changes in the blood glucose concentration may affect gastrointestinal motor function and the perception of sensations arising from the gastrointestinal tract. Erythromycin has been shown to accelerate gastric emptying in both normal subjects and patients with diabetes mellitus. The major aims of this study were to determine in normal subjects whether the effects of erythromycin on gastric emptying, and perceptions of hunger and fullness are modified by the blood glucose concentration. 10 normal subjects (aged 20-39 yr) underwent concurrent measurement of gastric emptying, blood glucose, hunger and fullness on four separate occasions: twice during euglycaemia (∼4 mmol/L) and twice during hyperglycaemia (∼15 mmol/L). Either erythromycin (3 mg/kg) or saline (0.9%) was administered intravenously immediately before ingestion of a radioisotopically labelled solid meal. Gastric emptying was slower (P<0.0001) during hyperglycaemia when compared to euglycaemia after both erythromycin and saline administration. Erythromycin accelerated the post-lag emptying rate during euglycaemia (P<0.05), but not hyperglycaemia. Hunger decreased (P<0.001) and fullness increased (P<0.001) after the meal Postprandial hunger was less (P<0.05) and fullness greater (P<0.05 during hyperglycaemia after saline infusion, but not after erythromycin. Hunger was greater after erythromycin when compared to saline during both hyperglycaemia and euglycaemia (P<0.05). In conclusion, at a blood glucose concentration of ∼15 mmol/L when compared to euglycaemia: (i) after administration of erythromycin (3 mg/kg IV) gastric emptying of a solid meal is much slower, (ii) the effect of erythromycin on gastric emptying of a solid meal is attenuated and (iii) the perception of postprandial hunger is reduced and that of fullness increased

Hyperglycaemia attenuates the gastrokinetic effect of erythromycin and affects the perception of postprandial hunger in normal subjects

Energy Technology Data Exchange (ETDEWEB)

Jones, K.L.; Berry, M.; Kong, M.F.; Kwiatek, M.; Samsom, M.; Horowitz, M. [University of South Australia, SA (Australia). School of Medicine Radiation]|[Royal Adelaide Hospital, SA (Australia). Department of Medicine

1998-06-01

Full text: Recent studies have demonstrated that acute changes in the blood glucose concentration may affect gastrointestinal motor function and the perception of sensations arising from the gastrointestinal tract. Erythromycin has been shown to accelerate gastric emptying in both normal subjects and patients with diabetes mellitus. The major aims of this study were to determine in normal subjects whether the effects of erythromycin on gastric emptying, and perceptions of hunger and fullness are modified by the blood glucose concentration. 10 normal subjects (aged 20-39 yr) underwent concurrent measurement of gastric emptying, blood glucose, hunger and fullness on four separate occasions: twice during euglycaemia ({approx}4 mmol/L) and twice during hyperglycaemia ({approx}15 mmol/L). Either erythromycin (3 mg/kg) or saline (0.9%) was administered intravenously immediately before ingestion of a radioisotopically labelled solid meal. Gastric emptying was slower (P<0.0001) during hyperglycaemia when compared to euglycaemia after both erythromycin and saline administration. Erythromycin accelerated the post-lag emptying rate during euglycaemia (P<0.05), but not hyperglycaemia. Hunger decreased (P<0.001) and fullness increased (P<0.001) after the meal Postprandial hunger was less (P<0.05) and fullness greater (P<0.05) during hyperglycaemia after saline infusion, but not after erythromycin. Hunger was greater after erythromycin when compared to saline during both hyperglycaemia and euglycaemia (P<0.05). In conclusion, at a blood glucose concentration of {approx}15 mmol/L when compared to euglycaemia: (i) after administration of erythromycin (3 mg/kg IV) gastric emptying of a solid meal is much slower, (ii) the effect of erythromycin on gastric emptying of a solid meal is attenuated and (iii) the perception of postprandial hunger is reduced and that of fullness increased

Subjective Age and Health Perceptions of Older Persons: Maintaining the Youthful Bias in Sickness and in Health.

Science.gov (United States)

Staats, Sara; And Others

1993-01-01

Self-reports of 250 persons over age 50 confirmed increasing bias toward reporting more youthful age as one ages. Optimistic perceptions of health were maintained in older subjects. Results from two subsets of sample (n=48) indicated that youthful and optimistic bias occurred both in older persons with poorer/failing health and in persons in…

Correlations between M-CHARTS and PHP findings and subjective perception of metamorphopsia in patients with macular diseases.

Science.gov (United States)

Arimura, Eiko; Matsumoto, Chota; Nomoto, Hiroki; Hashimoto, Shigeki; Takada, Sonoko; Okuyama, Sachiko; Shimomura, Yoshikazu

2011-01-05

To assess the correlations between a patient's subjective perception of metamorphopsia and the clinical measurements of metamorphopsia by M-CHARTS and PreView PHP (PHP). The authors designed a 10-item questionnaire focusing on the symptoms of metamorphopsia and verified its validity with a Rasch analysis. M-CHARTS measured the minimum visual angle of a dotted line needed to detect metamorphopsia, and PHP used the hyperacuity function for detection. Subjects were 39 patients with idiopathic epiretinal membrane (ERM), 22 patients with idiopathic macular hole (M-hole), 19 patients with age-related macular degeneration (AMD), and 51 healthy controls. Rasch analysis suggested the elimination of one question. The nine-item questionnaire score significantly correlated to the M-CHARTS score in ERM (r = 0.59; P = 0.0004) but not in M-hole and to the PHP result in AMD (r = -0.29; P = 0.04) but not in ERM. Eighty percent of ERM patients with greater horizontal M-CHARTS score subjectively perceived horizontal metamorphopsia more often. M-CHARTS showed better sensitivities than PHP in both ERM (89% vs. 42%) and AMD (74% vs. 68%) and better specificity (100% vs. 71%) in healthy controls. Rasch analysis indicated that the present form of the questionnaire is better suited for moderate to severe cases of metamorphopsia than for mild cases. The questionnaire appears to be a valid assessment of patient subjective perception of metamorphopsia and can be used to supplement the clinical measurements of metamorphopsia by M-CHARTS and PHP in patients with macular diseases.

Subjective visual vertical before and after treatment of a BPPV episode.

Science.gov (United States)

Faralli, Mario; Manzari, Leonardo; Panichi, Roberto; Botti, Fabio; Ricci, Giampietro; Longari, Fabrizio; Pettorossi, Vito Enrico

2011-06-01

The study analyses the behavior of subjective visual vertical (SVV) in benign paroxysmal positional vertigo (BPPV) before and after treatment, and offers a clinical-pathogenic interpretation. We studied 30 consecutive patients with BPPV of the posterior semicircular canal treated with the Epley repositioning maneuver. SVV was determined at three different stages: at the time of diagnosis (1st test), after the repositioning maneuver (2nd test), and then 7 days after the resolution of the clinical picture (3rd test). The main study parameter was represented by the mean of 6 consecutive measurements (SVV(0)) for each patient. SVV was also examined in 20 healthy subjects, who represented the control group. The comparison between mean values and standard deviations showed a statistical significance of p<0.05. During the first test, the degree of deviation of SVV was significantly higher in the patient group than in the control group. Tilting towards the affected side was observed in all cases. The 2nd test showed an inversion in the orientation of SVV in 16 patients, and as a result of the Epley maneuver there was a statistically significant variation in SVV(0) values in 20 patients with respect to the previous test (2nd test vs. 1st test). This involved 87% (23 patients) of those who then had a negative Dix-Hallpike test, and none of the ones in whom paroxysmal positional nystagmus persisted. Lastly, no differences emerged in the behavior of the patient group vs. the control group during the third test. SVV is often altered during active BPPV. The degree of otolithic dysfunction is never high and, in all cases, it is brief in duration. Tilting towards the dysfunctional side is essentially a constant in untreated BPPV. This could be due to a substantial loss of otoconia, with a decrease in the density and specific weight of the macula, and thus hypofunction of the receptor. The observation of a significant variation in SVV after therapeutic maneuvers has a favorable

Global Vertical Reference Frame

Czech Academy of Sciences Publication Activity Database

Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vojtíšková, M.

-, č. 5 (2009), s. 53-63 ISSN 1801-8483 R&D Projects: GA ČR GA205/08/0328 Institutional research plan: CEZ:AV0Z10030501 Keywords : sea surface topography * satellite altimetry * vertical frames Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

Subjective figures and texture perception.

Science.gov (United States)

Zucker, S W; Cavanagh, P

1985-01-01

A texture discrimination task using the Ehrenstein illusion demonstrates that subjective brightness effects can play an essential role in early vision. The subjectively bright regions of the Ehrenstein can be organized either as discs or as stripes, depending on orientation. The accuracy of discrimination between variants of the Ehrenstein and control patterns was a direct function of the presence of the illusory brightness stripes, being high when they were present and low otherwise. It is argued that neither receptive field structure nor spatial-frequency content can adequately account for these results. We suggest that the subjective brightness illusions, rather than being a high-level, cognitive aspect of vision, are in fact the result of an early visual process.

Relations between psychophysical data and speech perception for hearing-impaired subjects. II

NARCIS (Netherlands)

Dreschler, W. A.; Plomp, R.

1985-01-01

Twenty-one sensorineurally hearing-impaired adolescents were studied with an extensive battery of tone-perception, phoneme-perception, and speech-perception tests. Tests on loudness perception, frequency selectivity, and temporal resolution at the test frequencies of 500, 1000, and 2000 Hz were

Subjective perception of safety in healthy individuals working with 7 T MRI scanners: a retrospective multicenter survey.

Science.gov (United States)

Fatahi, Mahsa; Demenescu, Liliana Ramona; Speck, Oliver

2016-06-01

To retrospectively assess perception of safety of healthy individuals working with human 7 Tesla (T) magnetic resonance imaging (MRI) scanners. A total of 66 healthy individuals with a mean age of 31 ± 7 years participated in this retrospective multicentre survey study. Nonparametric correlation analysis was conducted to evaluate the relation between self-reported perception of safety and prevalence of sensory effects while working with 7 T MRI scanners for an average 47 months. The results indicated that 98.5 % of the study participants had a neutral or positive feeling about safety aspects at 7 T MRI scanners. 45.5 % reported that they feel very safe and none of the participants stated that they feel moderately or very unsafe while working with 7 T MRI scanners. Perception of safety was not affected by the number of hours per week spent in the vicinity of the 7 T MRI scanner or the duration of experience with 7 T MRI. More than 50 % of individuals experienced vertigo and metallic taste while working with 7 T MRI scanners. However, participants' perceptions of safety were not affected by the prevalence of MR-related symptoms. The overall data indicated an average perception of a moderately safe work environment. To our knowledge, this study delineates the first attempt to assess the subjective safety perception among 7 T MRI workers and suggests further investigations are indicated.

The upper spatial limit for perception of displacement is affected by preceding motion.

Science.gov (United States)

Stefanova, Miroslava; Mateeff, Stefan; Hohnsbein, Joachim

2009-03-01

The upper spatial limit D(max) for perception of apparent motion of a random dot pattern may be strongly affected by another, collinear, motion that precedes it [Mateeff, S., Stefanova, M., &. Hohnsbein, J. (2007). Perceived global direction of a compound of real and apparent motion. Vision Research, 47, 1455-1463]. In the present study this phenomenon was studied with two-dimensional motion stimuli. A random dot pattern moved alternately in the vertical and oblique direction (zig-zag motion). The vertical motion was of 1.04 degrees length; it was produced by three discrete spatial steps of the dots. Thereafter the dots were displaced by a single spatial step in oblique direction. Each motion lasted for 57ms. The upper spatial limit for perception of the oblique motion was measured under two conditions: the vertical component of the oblique motion and the vertical motion were either in the same or in opposite directions. It was found that the perception of the oblique motion was strongly influenced by the relative direction of the vertical motion that preceded it; in the "same" condition the upper spatial limit was much shorter than in the "opposite" condition. Decreasing the speed of the vertical motion reversed this effect. Interpretations based on networks of motion detectors and on Gestalt theory are discussed.

Subjective and objective perceptions of specular gloss and surface roughness of esthetic resin composites before and after artificial aging.

Science.gov (United States)

Barucci-Pfister, Nadine; Göhring, Till N

2009-04-01

To correlate measurements of specular gloss and surface roughness of resin composite materials with subjective perception of luster before and after artificial aging. Polished specimens of eight composites were compared with human enamel (HE): microfilled SR Adoro (SR); microhybrid Artemis (AR), Enamel HFO (EHFO), Miris (MI), Tetric Ceram (TC), Venus (VE); and nanohybrid CeramX (CX) and nanofilled Filtek Supreme (FS). Before, during and after artificial aging (6000 thermal changes between 5 degrees C and 50 degrees C in an artificial oral environment, 240 hours storage in a container with ethanol, 300 minutes of toothbrushing), specular gloss and surface roughness were measured. Initial and endpoint gloss results were correlated with subjective luster rankings of 10 individuals. Artificial aging resulted in minor (EHFO, CX, FS), moderate (SR, MI, TC, VE) to high (AR) increases in surface roughness. Specular gloss decreased linearly for SR and FS, but decreased after an initial increase for all other materials. Subjectively, AR and FS were rated more and TC, VE and CX less lustrous than HE at baseline. After aging, luster of EHFO and FS was ranked higher and AR, TC, and VE lower than HE. Surface roughness was consistent with subjective perceptions (correlation coefficient: initial r = 0.913; endpoint r = 0.944, P artificial aging (initial r = 0.616, P = 0.1084; endpoint r = 0.834, P = 0.0072).

Student perceptions and learning outcomes of blended learning in a massive first-year core physiology for allied health subjects.

Science.gov (United States)

Page, Janelle; Meehan-Andrews, Terri; Weerakkody, Nivan; Hughes, Diane L; Rathner, Joseph A

2017-03-01

Evidence shows that factors contributing to success in physiology education for allied health students at universities include not only their high school achievement and background but also factors such as confidence with their teachers and quality of their learning experience, justifying intensive and continued survey of students' perceptions of their learning experience. Here we report data covering a 3-yr period in a physiology subject that has been redesigned for blended and online presentation. Consistent with previous reports, we show that when we undertook a blended mode of delivery, students demonstrated better grades than traditional modes of teaching; however the absence of didactic teaching in this subject resulted in lower grades overall. Students have very strong positive attitudes to weekly quizzes (80% positive approval) but report ambivalent attitudes to online self-directed learning (61% negative perception), even though they had 2-h weekly facilitated workshops. Overwhelmingly, students who undertook the subject in a self-directed online learning mode requested more face-to-face-teaching (70% of comments). From these data, we suggest that there is a quantifiable benefit to didactic teaching in the blended teaching mode that is not reproduced in online self-directed learning, even when face-to-face guided inquiry-based learning is embedded in the subject. Copyright © 2017 the American Physiological Society.

Esophageal contractions, bolus transit and perception of transit after swallows of liquid and solid boluses in normal subjects

Directory of Open Access Journals (Sweden)

Juciléia Dalmazo

2012-12-01

Full Text Available CONTEXT: Esophageal dysphagia is the sensation that the ingested material has a slow transit or blockage in its normal passage to the stomach. It is not always associated with motility or transit alterations. OBJECTIVES: To evaluate in normal volunteers the possibility of perception of bolus transit through the esophagus after swallows of liquid and solid boluses, the differences in esophageal contraction and transit with these boluses, and the association of transit perception with alteration of esophageal contraction and/or transit. METHODS: The investigation included 11 asymptomatic volunteers, 4 men and 7 women aged 19-58 years. The subjects were evaluated in the sitting position. They performed swallows of the same volume of liquid (isotonic drink and solid (macaroni boluses in a random order and in duplicate. After each swallow they were asked about the sensation of bolus passage through the esophagus. Contractions and transit were evaluated simultaneously by solid state manometry and impedance. RESULTS: Perception of bolus transit occurred only with the solid bolus. The amplitude and area under the curve of contractions were higher with swallows of the solid bolus than with swallows of the liquid bolus. The difference was more evident in swallows with no perception of transit (n = 12 than in swallows with perception (n = 10. The total bolus transit time was longer for the solid bolus than for the liquid bolus only with swallows followed by no perception of transit. CONCLUSION: The results suggest that the perception of esophageal transit may be the consequence of inadequate adaptation of esophageal transit and contraction to the characteristics of the swallowed bolus.

The influence of non-linear frequency compression on the perception of music by adults with a moderate to sever hearing loss: subjective impressions.

Science.gov (United States)

Uys, Marinda; Pottas, Lidia; Vinck, Bart; van Dijk, Catherine

2012-12-01

To date, the main direction in frequency-lowering hearing aid studies has been in relation to speech perception abilities. With improvements in hearing aid technology, interest in musical perception as a dimension that could improve hearing aid users' quality of life has grown. The purpose of this study was to determine the influence of non-linear frequency compression (NFC) on hearing aid users' subjective impressions of listening to music. DESIGN & SAMPLE: A survey research design was implemented to elicit participants' (N=40) subjective impressions of musical stimuli with and without NFC. The use of NFC significantly improved hearing aid users' perception of the musical qualities of overall fidelity, tinniness and reverberance. Although participants preferred to listen to the loudness, fullness, crispness, naturalness and pleasantness of music with the use of NFC, these benefits were not significant. The use of NFC can increase hearing aid users' enjoyment and appreciation of music. Given that a relatively large percentage of hearing aid users express a loss of enjoyment of music, audiologists should not ignore the possible benefits of NFC, especially if one takes into account that previous research indicates speech perception benefits with this technology.

The influence of non-linear frequency compression on the perception of music by adults with a moderate to severe hearing loss: Subjective impressions

Directory of Open Access Journals (Sweden)

Marinda Uys

2012-12-01

Full Text Available Objective: To date, the main direction in frequency-lowering hearing aid studies has been in relation to speech perception abilities. With improvements in hearing aid technology, interest in musical perception as a dimension that could improve hearing aid users’ quality of life has grown. The purpose of this study was to determine the influence of non-linear frequency compression (NFC on hearing aid users’ subjective impressions of listening to music. Design & sample: A survey research design was implemented to elicit participants’ (N=40 subjective impressions of musical stimuli with and without NFC. Results: The use of NFC significantly improved hearing aid users’ perception of the musical qualities of overall fidelity, tinniness and reverberance. Although participants preferred to listen to the loudness, fullness, crispness, naturalness and pleasantness of music with the use of NFC, these benefits were not significant. Conclusion: The use of NFC can increase hearing aid users’ enjoyment and appreciation of music. Given that a relatively large percentage of hearing aid users express a loss of enjoyment of music, audiologists should not ignore the possible benefits of NFC, especially if one takes into account that previous research indicates speech perception benefits with this technology.

Fatty acid profile in vertical strata of elephant grass subjected to intermittent stocking

Directory of Open Access Journals (Sweden)

KAMILA M. DIAS

2017-08-01

Full Text Available ABSTRACT The milk and meat from animals with a pasture-based diet have higher proportions of CLA and C18:3 and lower omega-6:omega-3 ratios than products from animals with diets based on corn silage and concentrate. However, most of the published studies have evaluated fatty acid profiles in temperate climate grasses and the literature with tropical grasses is scarce. Thus, the aim of this study was to evaluate the morphological and fatty acid compositions in the vertical strata of elephant grass (Pennisetum purpureum Schum. swards subjected to grazing heights (90 or 120 cm pre-grazing heights and levels of defoliation (50% or 70% removal of the initial pre-grazing height. There were no interactions among pre-grazing height, the level of defoliation and grazing stratum. However, higher proportion of C18:3 (58% and 63% was found in the 90-cm swards and in the half upper stratum. A higher proportion of C18:3 was associated with a higher leaf proportion and crude protein content. Thus, the upper stratum of sward or a grazing management scheme (e.g. first-last stocking resulting in a higher proportion of leaves and crude protein both provide higher proportions of C18:3 to animals grazing in elephant grass swards.

Characterization of vertical mixing in oscillatory vegetated flows

Science.gov (United States)

Abdolahpour, M.; Ghisalberti, M.; Lavery, P.; McMahon, K.

2016-02-01

Seagrass meadows are primary producers that provide important ecosystem services, such as improved water quality, sediment stabilisation and trapping and recycling of nutrients. Most of these ecological services are strongly influenced by the vertical exchange of water across the canopy-water interface. That is, vertical mixing is the main hydrodynamic process governing the large-scale ecological and environmental impact of seagrass meadows. The majority of studies into mixing in vegetated flows have focused on steady flow environments whereas many coastal canopies are subjected to oscillatory flows driven by surface waves. It is known that the rate of mass transfer will vary greatly between unidirectional and oscillatory flows, necessitating a specific investigation of mixing in oscillatory canopy flows. In this study, we conducted an extensive laboratory investigation to characterise the rate of vertical mixing through a vertical turbulent diffusivity (Dt,z). This has been done through gauging the evolution of vertical profiles of concentration (C) of a dye sheet injected into a wave-canopy flow. Instantaneous measurement of the variance of the vertical concentration distribution ( allowed the estimation of a vertical turbulent diffusivity (). Two types of model canopies, rigid and flexible, with identical heights and frontal areas, were subjected to a wide and realistic range of wave height and period. The results showed two important mechanisms that dominate vertical mixing under different conditions: a shear layer that forms at the top of the canopy and wake turbulence generated by the stems. By allowing a coupled contribution of wake and shear layer mixing, we present a relationship that can be used to predict the rate of vertical mixing in coastal canopies. The results further showed that the rate of vertical mixing within flexible vegetation was always lower than the corresponding rigid canopy, confirming the impact of plant flexibility on canopy

Neurophysiology of the cortical pain network: revisiting the role of S1 in subjective pain perception via standardized low-resolution brain electromagnetic tomography (sLORETA).

Science.gov (United States)

Nir, Rony-Reuven; Lev, Rina; Moont, Ruth; Granovsky, Yelena; Sprecher, Elliot; Yarnitsky, David

2008-11-01

Multiple studies have supported the usefulness of standardized low-resolution brain electromagnetic tomography (sLORETA) in localizing generators of scalp-recorded potentials. The current study implemented sLORETA on pain event-related potentials, primarily aiming at validating this technique for pain research by identifying well-known pain-related regions. Subsequently, we pointed at investigating the still-debated and ambiguous topic of pain intensity coding at these regions, focusing on their relative impact on subjective pain perception. sLORETA revealed significant activations of the bilateral primary somatosensory (SI) and anterior cingulate cortices and of the contralateral operculoinsular and dorsolateral prefrontal (DLPFC) cortices (P < .05 for each). Activity of these regions, excluding DLPFC, correlated with subjective numerical pain scores (P < .05 for each). However, a multivariate regression analysis (R = .80; P = .024) distinguished the contralateral SI as the only region whose activation magnitude significantly predicted the subjective perception of noxious stimuli (P = .020), further substantiated by a reduced regression model (R = .75, P = .008). Based on (1) correspondence of the pain-activated regions identified by sLORETA with the acknowledged imaging-based pain-network and (2) the contralateral SI proving to be the most contributing region in pain intensity coding, we found sLORETA to be an appropriate tool for relevant pain research and further substantiated the role of SI in pain perception. Because the literature of pain intensity coding offers inconsistent findings, the current article used a novel tool for revisiting this controversial issue. Results suggest that it is the activation magnitude of SI, which solely establishes the significant correlation with subjective pain ratings, in accordance with the classical clinical thinking, relating SI lesions to diminished perception of pain. Although this study cannot support a causal relation

Associations between women's subjective perceptions of daily occupations and life satisfaction, and the role of perceived control.

Science.gov (United States)

Håkansson, Carita; Björkelund, Cecilia; Eklund, Mona

2011-12-01

More knowledge is needed about the role of perceived control in the associations between different perceptions of daily occupations and positive health outcomes. The aim was to explore the associations between different subjective perceptions of daily occupations, in terms of occupational balance, occupational meaning, occupational value and satisfaction with occupations, and life satisfaction, and the role of perceived control in those associations. A questionnaire including questions about perceptions of daily occupations, perceived control and life satisfaction were answered by a random sample of 488 middle-aged Swedish women. Multiple logistic regression analysis was used to test the associations between perceptions of daily occupations and life satisfaction, and the role of perceived control. After adjustments for perceived control women who perceived a high level of satisfaction with work and leisure, occupational balance, occupational meaning and occupational value perceived greater life satisfaction than the other women. Perceived control was not significant in the model. It seems that occupational balance and occupational meaning were pivotal for the women's life satisfaction, but satisfaction with work and leisure, as well as perceived occupational value, was also of importance. The assumption that perceived control would have a role in the association between perceptions of occupations and life satisfaction was not confirmed. The results indicate that occupational therapists need to focus on occupational balance, occupational meaning, occupational value and satisfaction with work and leisure to promote positive health outcomes, in terms of life satisfaction, when working with middle-aged female clients. © 2011 The Authors. Australian Occupational Therapy Journal © 2011 Occupational Therapy Australia.

The correlates of subjective perception of identity and expression in the face network: an fMRI adaptation study.

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Fox, Christopher J; Moon, So Young; Iaria, Giuseppe; Barton, Jason J S

2009-01-15

The recognition of facial identity and expression are distinct tasks, with current models hypothesizing anatomic segregation of processing within a face-processing network. Using fMRI adaptation and a region-of-interest approach, we assessed how the perception of identity and expression changes in morphed stimuli affected the signal within this network, by contrasting (a) changes that crossed categorical boundaries of identity or expression with those that did not, and (b) changes that subjects perceived as causing identity or expression to change, versus changes that they perceived as not affecting the category of identity or expression. The occipital face area (OFA) was sensitive to any structural change in a face, whether it was identity or expression, but its signal did not correlate with whether subjects perceived a change or not. Both the fusiform face area (FFA) and the posterior superior temporal sulcus (pSTS) showed release from adaptation when subjects perceived a change in either identity or expression, although in the pSTS this effect only occurred when subjects were explicitly attending to expression. The middle superior temporal sulcus (mSTS) showed release from adaptation for expression only, and the precuneus for identity only. The data support models where the OFA is involved in the early perception of facial structure. However, evidence for a functional overlap in the FFA and pSTS, with both identity and expression signals in both areas, argues against a complete independence of identity and expression processing in these regions of the core face-processing network.

Salivary Alpha-Amylase Correlates with Subjective Heat Pain Perception.

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Wittwer, Amrei; Krummenacher, Peter; La Marca, Roberto; Ehlert, Ulrike; Folkers, Gerd

2016-06-01

Self-reports of pain are important for an adequate therapy. This is a problem with patients and infants who are restricted in providing an accurate verbal estimation of their pain. Reliable, real-time, economical, and non-invasive physiological correlates might contribute to a more comprehensive description of pain. Salivary alpha-amylase constitutes one candidate biomarker, which reflects predominantly sympathetic nervous system alterations under stressful conditions and can be measured non-invasively. The current study investigated the effects of acute heat pain on salivary alpha-amylase activity. Heat pain tolerance was measured on the non-dominant forearm. Participants completed visual analog scales on pain intensity and unpleasantness. Saliva samples were collected directly after pain induction. Twenty-seven healthy volunteers were recruited for this study. While salivary alpha-amylase levels correlated positively with intensity and unpleasantness ratings in response to acute heat pain stimuli, there was no corresponding association with pain tolerance. Salivary alpha-amylase is suggested to be an indirect physiologic correlate of subjective heat pain perception. Future studies should address the role of salivary alpha-amylase depending on the origin of pain, the concerned tissue, and other pain assessment methods. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Developmental Color Perception

Science.gov (United States)

Gaines, Rosslyn; Little, Angela C.

1975-01-01

A sample of 107 subjects including kindergarteners, fifth graders, high school sophomores, parents of kindergarteners, and master artists were presented with a 108-item color perception test to investigate surface color perception at these age levels. A set of surface color perception rules was generated. (GO)

(Re)examining the Relationship Between Children's Subjective Wellbeing and Their Perceptions of Participation Rights.

Science.gov (United States)

Lloyd, Katrina; Emerson, Lesley

2017-01-01

In recent years wellbeing has been linked increasingly with children's rights, often characterised as central to their realisation. Indeed it has been suggested that the two concepts are so intertwined that their pairing has become something of a mantra in the literature on childhood. This paper seeks to explore the nature of the relationship between wellbeing and participation rights, using a recently developed 'rights-based' measure of children's participation in school and community, the Children's Participation Rights Questionnaire (CPRQ), and an established measure of subjective wellbeing - KIDSCREEN-10. The data for the study came from the Kids' Life and Times (KLT) which is an annual online survey of Primary 7 children carried out in Northern Ireland. In 2013 approximately 3800 children (51 % girls; 49 % boys) from 212 schools participated in KLT. The findings showed a statistically significant positive correlation between children's overall scores on the KIDSCREEN-10 subjective wellbeing measure and their perceptions that their participation rights are respected in school and community settings. Further, the results indicated that it is the social relations/autonomy questions on KIDSCREEN-10 which are most strongly related to children's perceptions that their participation rights are respected. Exploration of the findings by gender showed that there were no significant differences in overall wellbeing; however girls had higher scores than boys on the social relations/autonomy domain of KIDSCREEN-10. Girls were also more positive than boys about their participation in school and community. In light of the findings from this study, it is suggested that what lies at the heart of the relationship between child wellbeing and children's participation rights is the social/relational aspects of both participation and wellbeing.

Perception, time of perception, perception of the time

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Barata, André

2009-04-01

Full Text Available From a conceptual point of view, time is independent of its experience. That is: it can be given a conceptual description of time without any reference to terms related to the subjective consciousness of time. But concerning a phenomenology of that subjective experience of time, it can it be showed that such experience of time is, in itself, temporal. The very same terms employed in a conceptual description of time – terms like “change” and “duration”– are implied in the phenomenological description of every perception, including perception of time. This authorizes a characterization of subjective time experience as subjective time. At last, based on temporal nature of perception of time, I will suggest an explanation for our common experience of asymmetries subjective time and objective time.Desde un punto de vista conceptual, el tiempo es independiente respecto de la experiencia del tiempo. Es decir: puede darse una descripción conceptual del tiempo sin referencia ninguna a términos relacionados con la conciencia subjetiva del tiempo. Pero en lo concerniente a una fenomenología de esa experiencia subjetiva del tiempo, puede revelarse que tal experiencia de tiempo es, ella en sí misma, temporal? Los mismísimos términos empleados en una descripción conceptual del tiempo, como “cambio” y “duración”, están implicados en la descripción fenomenológica de toda percepción, incluida la percepción del tiempo. Esto autoriza una caracterización de la experiencia subjetiva del tiempo como tiempo subjetivo. Finalmente, sobre la base de la naturaleza temporal de la percepción del tiempo, sugeriré una explicación racional de nuestra experiencia común de asimetrías entre el tiempo subjetivo y el tiempo objetivo.

Pleasant touch moderates the subjective but not objective aspects of body perception

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Donna Marie Lloyd

2013-12-01

Full Text Available Un-myelinated C tactile afferents (CT afferents are a key finding in affective touch. These fibres, which activate in response to a caress-like touch to hairy skin (CT afferents are not found in palm skin, may have more in common with interoceptive systems encoding body ownership, than afferent systems processing other tactile stimuli. We tested whether subjective embodiment of a rubber hand (measured through questionnaire items was increased when tactile stimulation was applied to the back of the hand at a rate optimal for CT afferents (3cm/s vs. stimulation of glabrous skin (on the palm of the hand or at a non-optimal rate (30cm/s, which should not activate these fibres. We also collected ratings of tactile pleasantness and a measure of perceived limb position, proprioceptive drift, which is mediated by different mechanisms of multisensory integration than those responsible for feelings of ownership. The results of a multiple regression analysis revealed that proprioceptive drift was a significant predictor of subjective strength of the illusion when tactile stimuli were applied to the back of the hand, regardless of stroking speed. This relationship was modified by pleasantness, with higher ratings when stimulation was applied to the back of the hand at the slower vs. faster stroking speed. Pleasantness was also a unique predictor of illusion strength when fast stroking was applied to the palm of the hand. However, there were no conditions under which pleasantness was a significant predictor of drift. Since the illusion was demonstrated at a non-optimal stroking speed an integrative role for CT afferents within the illusion cannot be fully supported. Pleasant touch, however, does moderate the subjective aspects of the rubber hand illusion, which under certain tactile conditions may interact with proprioceptive information about the body or have a unique influence on subjective body perception.

HIV-Positive Patients' Perceptions of Antiretroviral Therapy Adherence in Relation to Subjective Time: Imprinting, Domino Effects, and Future Shadowing.

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Lessard, David; Toupin, Isabelle; Engler, Kim; Lènàrt, Andràs; Lebouché, Bertrand

2018-01-01

Antiretroviral treatment adherence barriers are major concerns in HIV care. They are multiple and change over time. Considering temporality in patients' perceptions of adherence barriers could improve adherence management. We explored how temporality manifests itself in patients' perceptions of adherence barriers. We conducted 2 semi-structured focus groups on adherence barriers with 12 adults with HIV which were analyzed with grounded theory. A third focus group served to validate the results obtained. Three temporal categories were manifest in HIV-positive patients' perceptions of barriers: (1) imprinting (events with lasting impacts on patients), (2) domino effects (chain of life events), and (3) future shadowing (apprehension about long-term adherence). An overarching theme, weathering (gradual erosion of abilities to adhere), traversed these categories. These temporalities explain how similar barriers may be perceived differently by patients. They could be useful to providers for adapting their interventions and improving understanding of patients' subjective experience of adherence.

Subjective Health Complaints in Individuals with Psoriasis and Psoriatic Arthritis: Associations with the Severity of the Skin Condition and Illness Perceptions - A Cross-Sectional Study.

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Nordbø, Emma Charlott Andersson; Aamodt, Geir; Ihlebæk, Camilla Martha

2017-06-01

High comorbidity has been reported among persons with psoriasis and psoriatic arthritis (PsA), but the occurrence of subjective health complaints (SHCs) in these patient groups is poorly understood. The study aimed to describe the prevalence of SHCs among individuals with psoriasis and PsA in Norway, and investigate whether the severity of their skin condition and their illness perceptions were associated with the number and severity of health complaints. Participants were recruited through the Psoriasis and Eczema Association of Norway (PEF) (n = 942). The participants answered a self-administered questionnaire covering subjective health complaints, the severity of their skin condition, and their illness perceptions measured with the Brief Illness Perception Questionnaire (BIPQ-R). The prevalence and severity of SHCs were high. Participants with PsA reported more complaints and higher severity of complaints compared with participants with psoriasis. In both groups, the severity of the skin condition was associated with the number and severity of SHCs. Cognitive illness perceptions (consequences) and emotional illness perceptions (emotional affect) were associated with SHCs in participants with psoriasis, whereas only cognitive illness perceptions (consequences and identity) were associated with SHCs in participants with PsA. The high prevalence and severity of SHCs among individuals with psoriasis and PsA were associated with the severity of the skin condition and illness perceptions. Somatic and cognitive sensitizations are proposed as possible mechanisms. The findings suggest that holistic approaches are essential when managing these patient groups in health care institutions and clinical practice.

College Students Perceptions of Web-Based Leaning in Basic Mathematics Subject

Science.gov (United States)

Husna, H.; Septia, T.; Cesaria, A.

2018-04-01

With the emergence of the Internet, e-learning has increasingly become the promising solution that continues to grow day after day. Considering students’ perception toward e-learning is important in successful development of e-learning in higher education, since attitude of user towards application of information technology is one of the most effective factors. This study aims to determine students' perceptions of using basic math textbook for physics with web-based. Students' perceptions are closely related to their achievement. The learning media in accordance with the desire of students will make them motivated. This research is qualitative data analysis was done descriptively. The data obtained in this study comes from researchers as the main instrument, the data questionnaire and interview data is unstructured. The results are students' perceptions of using basic math textbook for physics with web-based are in the positive category.

Effects of Frequency and Motion Paradigm on Perception of Tilt and Translation During Periodic Linear Acceleration

Science.gov (United States)

Beaton, K. H.; Holly, J. E.; Clement, G. R.; Wood, Scott J.

2009-01-01

Previous studies have demonstrated an effect of frequency on the gain of tilt and translation perception. Results from different motion paradigms are often combined to extend the stimulus frequency range. For example, Off-Vertical Axis Rotation (OVAR) and Variable Radius Centrifugation (VRC) are useful to test low frequencies of linear acceleration at amplitudes that would require impractical sled lengths. The purpose of this study was to compare roll-tilt and lateral translation motion perception in 12 healthy subjects across four paradigms: OVAR, VRC, sled translation and rotation about an earth-horizontal axis. Subjects were oscillated in darkness at six frequencies from 0.01875 to 0.6 Hz (peak acceleration equivalent to 10 deg, less for sled motion below 0.15 Hz). Subjects verbally described the amplitude of perceived tilt and translation, and used a joystick to indicate the direction of motion. Consistent with previous reports, tilt perception gain decreased as a function of stimulus frequency in the motion paradigms without concordant canal tilt cues (OVAR, VRC and Sled). Translation perception gain was negligible at low stimulus frequencies and increased at higher frequencies. There were no significant differences between the phase of tilt and translation, nor did the phase significantly vary across stimulus frequency. There were differences in perception gain across the different paradigms. Paradigms that included actual tilt stimuli had the larger tilt gains, and paradigms that included actual translation stimuli had larger translation gains. In addition, the frequency at which there was a crossover of tilt and translation gains appeared to vary across motion paradigm between 0.15 and 0.3 Hz. Since the linear acceleration in the head lateral plane was equivalent across paradigms, differences in gain may be attributable to the presence of linear accelerations in orthogonal directions and/or cognitive aspects based on the expected motion paths.

Fatty acid translocase gene CD36 rs1527483 variant influences oral fat perception in Malaysian subjects.

Science.gov (United States)

Ong, Hing-Huat; Tan, Yen-Nee; Say, Yee-How

2017-01-01

We determined whether single nucleotide polymorphisms (SNPs; rs1761667 and rs1527483) in the fatty acid translocase CD36 gene - a receptor for fatty acids - is associated with oral fat perception (OFP) of different fat contents in custards and commercially-available foods, and obesity measures in Malaysian subjects (n=313; 118 males, 293 ethnic Chinese; 20 ethnic Indians). A 170-mm visual analogue scale was used to assess the ratings of perceived fat content, oiliness and creaminess of 0%, 2%, 6% and 10% fat content-by-weight custards and low-fat/regular versions of commercially-available milk, mayonnaise and cream crackers. Overall, the subjects managed to significantly discriminate the fat content, oiliness and creaminess between low-fat/regular versions of milk and mayonnaise. Females rated the perception of fat content and oiliness of both milks higher, but ethnicity, obesity and adiposity status did not seem to play a role in influencing most of OFP. The overall minor allele frequencies for rs1761667 and rs1527483 were 0.30 and 0.26, respectively. Females and individuals with rs1527483 TT genotype significantly perceived greater creaminess of 10% fat-by-weight custard. Also, individuals with rs1527483 TT genotype and T allele significantly perceived greater fat content of cream crackers, independent of fat concentration. rs1761667 SNP did not significantly affect OFP, except for cream crackers. Both gene variants were also not associated with obesity measures. Taken together, this study supports the notion that CD36 - specifically rs1527483, plays a role in OFP, but not in influencing obesity in Malaysian subjects. Besides, gender is an important factor for OFP, where females had higher sensitivity. Copyright © 2016 Elsevier Inc. All rights reserved.

The application of subjective job task analysis techniques in physically demanding occupations: evidence for the presence of self-serving bias.

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Lee-Bates, Benjamin; Billing, Daniel C; Caputi, Peter; Carstairs, Greg L; Linnane, Denise; Middleton, Kane

2017-09-01

The aim of this study was to determine if perceptions of physically demanding job tasks are biased by employee demographics and employment profile characteristics including: age, sex, experience, length of tenure, rank and if they completed or supervised a task. Surveys were administered to 427 Royal Australian Navy personnel who characterised 33 tasks in terms of physical effort, importance, frequency, duration and vertical/horizontal distance travelled. Results showed no evidence of bias resulting from participant characteristics, however participants who were actively involved in both task participation and supervision rated these tasks as more important than those involved only in the supervision of that task. This may indicate self-serving bias in which participants that are more actively involved in a task had an inflated perception of that task's importance. These results have important implications for the conduct of job task analyses, especially the use of subjective methodologies in the development of scientifically defensible physical employment standards. Practitioner Summary: To examine the presence of systematic bias in subjective job task analysis methodologies, a survey was conducted on a sample of Royal Australian Navy personnel. The relationship between job task descriptions and participant's demographic and job profile characteristics revealed the presence of self-serving bias affecting perceptions of task importance.

Interplay of Gravicentric, Egocentric, and Visual Cues About the Vertical in the Control of Arm Movement Direction.

Science.gov (United States)

Bock, Otmar; Bury, Nils

2018-03-01

Our perception of the vertical corresponds to the weighted sum of gravicentric, egocentric, and visual cues. Here we evaluate the interplay of those cues not for the perceived but rather for the motor vertical. Participants were asked to flip an omnidirectional switch down while their egocentric vertical was dissociated from their visual-gravicentric vertical. Responses were directed mid-between the two verticals; specifically, the data suggest that the relative weight of congruent visual-gravicentric cues averages 0.62, and correspondingly, the relative weight of egocentric cues averages 0.38. We conclude that the interplay of visual-gravicentric cues with egocentric cues is similar for the motor and for the perceived vertical. Unexpectedly, we observed a consistent dependence of the motor vertical on hand position, possibly mediated by hand orientation or by spatial selective attention.

A Conceptual Framework for Leisure and Subjective Well-Being

Science.gov (United States)

Kim, Byunggook

2009-01-01

The purpose of this study was to examine a conceptual framework for an individual's subjective perception of leisure that contributes to Subjective Well-Being (SWB). More specifically, this study was an attempt to examine causal relationships among social cognitive variables, subjective perception of leisure, and SWB. A survey was administered to…

Effect of a submaximal half-squats warm-up program on vertical jumping ability.

Science.gov (United States)

Gourgoulis, Vassilios; Aggeloussis, Nickos; Kasimatis, Panagiotis; Mavromatis, Giorgos; Garas, Athanasios

2003-05-01

The purpose of the current research was to study the effect of a warm-up program including submaximal half-squats on vertical jumping ability. Twenty physically active men participated in the study. Each subject performed 5 sets of half-squats with 2 repetitions at each of the following intensities: 20, 40, 60, 80, and 90% of the 1 repetition maximum (1RM) load. Prior to the first set and immediately after the end of the last set, the subjects performed 2 countermovement jumps on a Kistler force platform; the primary goal was to jump as high as possible. The results showed that mean vertical jumping ability improved by 2.39% after the warm-up period. Subjects were then divided into 2 groups according to their 1RM values for the half-squat. Subjects with greater maximal strength ability improved their vertical jumping ability (4.01%) more than did subjects with lower maximal strength (0.42%). A warm-up protocol including half-squats with submaximal loads and explosive execution can be used for short-term improvements of vertical jumping performance, and this effect is greater in athletes with a relatively high strength ability.

Perceiving the vertical distances of surfaces by means of a hand-held probe.

Science.gov (United States)

Chan, T C; Turvey, M T

1991-05-01

Nine experiments were conducted on the haptic capacity of people to perceive the distances of horizontal surfaces solely on the basis of mechanical stimulation resulting from contacting the surfaces with a vertically held rod. Participants touched target surfaces with rods inside a wooden cabinet and reported the perceived surface location with an indicator outside the cabinet. The target surface, rod, and the participant's hand were occluded, and the sound produced in exploration was muffled. Properties of the probe (length, mass, moment of inertia, center of mass, and shape) were manipulated, along with surface distance and the method and angle of probing. Results suggest that for the most common method of probing, namely, tapping, perceived vertical distance is specific to a particular relation among the rotational inertia of the probe, the distance of the point of contact with the surface from the probe's center of percussion, and the inclination at contact of the probe to the surface. They also suggest that the probe length and the distance probed are independently perceivable. The results were discussed in terms of information specificity versus percept-percept coupling and parallels between selective attention in haptic and visual perception.

The perception of hazards

International Nuclear Information System (INIS)

Fritzsche, A.F.

1986-01-01

The fourth chapter deals with the profusion of factors determining the differing assessment of hazards by our society. Subjective factors influencing risk perception comprise, among others, general knowledge and recognition of a hazard; the degree of voluntariness when taking the risk and its influencibility; the problem of large scale accidents; immediate and delayed results. Next to the objective and the subjective risks, the individual and the social or collective risks are assessed differently. The author dicusses in detail recent investigations into and study methods for the determination of risk perception, while eliminating systematic trends from subjective perception since common assessments are shared by whole groups of individuals time and again which allow a better understanding of today's handling of hazards. (HSCH) [de

New Vertical Marketing of Producers and Small Traders

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Zdenko Segetlija

2009-12-01

Full Text Available In relations of producers and small traders, diferent forms of vertical marketing develop a long time. However, under the contemporary conditions of retail global companies, the question is frst about conception of products categories called category management – CM. Namely, the prerequisites of business success of contemporary retail economic subjects in new highly competitive environment hide in the implementation of new managing conceptions and new technologies. This paper first gives a short analysis of some former theoretical cooperation viewpoints of producers and traders in marketing channels; later, it analyzes the basic assumptions of new vertical marketing on which rests the conception of category management. Besides, the paper states the application possibilities of the stated conception from the trader’s point of view. The basic hypothesis from which the authors start is the indispensability of vertical marketing application in the relations of contemporary retail economic subjects and producers in all market economies and the implementation of category management in its structure.

Tonic pain and continuous EEG: prediction of subjective pain perception by alpha-1 power during stimulation and at rest.

Science.gov (United States)

Nir, Rony-Reuven; Sinai, Alon; Moont, Ruth; Harari, Eyal; Yarnitsky, David

2012-03-01

Pain neurophysiology has been chiefly characterized via event-related potentials (ERPs), which are exerted using brief, phase-locked noxious stimuli. Striving for objectively characterizing clinical pain states using more natural, prolonged stimuli, tonic pain has been recently associated with the individual peak frequency of alpha oscillations. This finding encouraged us to explore whether alpha power, reflecting the magnitude of the synchronized activity within this frequency range, will demonstrate a corresponding relationship with subjective perception of tonic pain. Five-minute-long continuous EEG was recorded in 18 healthy volunteers under: (i) resting-state; (ii) innocuous temperature; and (iii) psychophysically-anchored noxious temperature. Numerical pain scores (NPSs) collected during the application of tonic noxious stimuli were tested for correlation with alpha-1 and alpha-2 power. NPSs and alpha power remained stable throughout the recording conditions (Ps⩾0.381). In the noxious condition, alpha-1 power obtained at the bilateral temporal scalp was negatively correlated with NPSs (Ps⩽0.04). Additionally, resting-state alpha-1 power recorded at the bilateral temporal scalp was negatively correlated with NPSs reported during the noxious condition (Ps⩽0.038). Current findings suggest alpha-1 power may serve as a direct, objective and experimentally stable measure of subjective perception of tonic pain. Furthermore, resting-state alpha-1 power might reflect individuals' inherent tonic pain responsiveness. The relevance of alpha-1 power to tonic pain perception may deepen the understanding of the mechanisms underlying the processing of prolonged noxious stimulation. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Stimulation in the dorsolateral prefrontal cortex changes subjective evaluation of percepts.

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Tzu-Ching Chiang

Full Text Available Nelson and Narens have proposed a metacognition model that dissociates the objective processing of information (object-level and the subjective evaluation of the performance (i.e., the metalevel. Neurophysiological evidence also indicates that the prefrontal cortices (PFC are the brain areas which perform the metalevel function [1]-[3]. A corresponding neural mechanism of Nelson and Narens's model, called dynamic filtering theory [4], [5], indicates that object-level processing is distributed in the posterior cortices and regulated by the prefrontal cortices with a filtering or gating mechanism to select appropriate signals and suppress inappropriate signals and noise. Based on this model, a hypothesis can be developed that, in the case of uncertainty or overloading of object-level processing, the prefrontal cortices will become more active in order to modulate signals and noise. This hypothesis is supported by a recent fMRI study [6] showing that the PFC (Brodmann area 9, BA9 was activated when subjects were overloaded in a bimodal attentional task, compared to a unimodal task. Here, we report a study showing that applying repetitive transmagnetic stimulation (rTMS over the BA9 in order to interfere with its functional activity resulted in significant increas in guessed responses, compared to three other control conditions (i.e., no-TMS, sham TMS on BA9, and rTMS on Cz. The results are compatible with the dynamic filtering theory and suggest that a malfunction of the PFC would weaken the quality of meta-cognitive percepts and increase the number of guessed responses.

War or Peace? How the Subjective Perception of Great Power Interdependence Shapes Preemptive Defensive Aggression.

Science.gov (United States)

Jing, Yiming; Gries, Peter H; Li, Yang; Stivers, Adam W; Mifune, Nobuhiro; Kuhlman, D M; Bai, Liying

2017-01-01

Why do great powers with benign intentions end up fighting each other in wars they do not seek? We utilize an incentivized, two-person "Preemptive Strike Game" (PSG) to explore how the subjective perception of great power interdependence shapes defensive aggression against persons from rival great powers. In Study 1, college students from the United States ( N = 115), China ( N = 106), and Japan ( N = 99) made PSG decisions facing each other. This natural experiment revealed that Chinese and Japanese participants (a) made more preemptive attacks against each other and Americans than against their compatriots, and that (b) greater preexisting perceptions of bilateral competition increased intergroup attack rates. In Study 2, adult Americans ( N = 127) watched real CNN expert interviews portraying United States-China economic interdependence as more positive or negative. This randomized experiment revealed that the more positive portrayal reduced preemptive American strikes against Chinese (but not Japanese), while the more negative portrayal amplified American anger about China's rise, increasing preemptive attacks against Chinese. We also found, however, that preemptive strikes were primarily defensive and not offensive. Interventions to reduce defensive aggression and promote great power peace are discussed.

War or Peace? How the Subjective Perception of Great Power Interdependence Shapes Preemptive Defensive Aggression

Directory of Open Access Journals (Sweden)

Yiming Jing

2017-06-01

Full Text Available Why do great powers with benign intentions end up fighting each other in wars they do not seek? We utilize an incentivized, two-person “Preemptive Strike Game” (PSG to explore how the subjective perception of great power interdependence shapes defensive aggression against persons from rival great powers. In Study 1, college students from the United States (N = 115, China (N = 106, and Japan (N = 99 made PSG decisions facing each other. This natural experiment revealed that Chinese and Japanese participants (a made more preemptive attacks against each other and Americans than against their compatriots, and that (b greater preexisting perceptions of bilateral competition increased intergroup attack rates. In Study 2, adult Americans (N = 127 watched real CNN expert interviews portraying United States–China economic interdependence as more positive or negative. This randomized experiment revealed that the more positive portrayal reduced preemptive American strikes against Chinese (but not Japanese, while the more negative portrayal amplified American anger about China’s rise, increasing preemptive attacks against Chinese. We also found, however, that preemptive strikes were primarily defensive and not offensive. Interventions to reduce defensive aggression and promote great power peace are discussed.

Vertical Dynamic Stiffness of Offshore Foundations

DEFF Research Database (Denmark)

Latini, Chiara; Cisternino, Michele; Zania, Varvara

2016-01-01

Nowadays, pile and suction caisson foundations are widely used to support offshore structures which are subjected to vertical dynamic loads. The dynamic soil-structure interaction of floating foundations (foundations embedded in a soil layer whose height is greater than the foundation length) is ...

Sands subjected to repetitive vertical loading under zero lateral strain: accumulation models, terminal densities, and settlement

KAUST Repository

Chong, Song Hun

2016-08-09

Geosystems often experience numerous loading cycles. Plastic strain accumulation during repetitive mechanical loads can lead to shear shakedown or continued shear ratcheting; in all cases, volumetric strains diminish as the specimen evolves towards terminal density. Previously suggested models and new functions are identified to fit plastic strain accumulation data. All accumulation models are formulated to capture terminal density (volumetric strain) and either shakedown or ratcheting (shear strain). Repetitive vertical loading tests under zero lateral strain conditions are conducted using three different sands packed at initially low and high densities. Test results show that plastic strain accumulation for all sands and density conditions can be captured in the same dimensionless plot defined in terms of the initial relative density, terminal density, and ratio between the amplitude of the repetitive load and the initial static load. This observation allows us to advance a simple but robust procedure to estimate the maximum one-dimensional settlement that a foundation could experience if subjected to repetitive loads. © 2016, Canadian Science Publishing. All rights reserved.

What's "up" with God? Vertical space as a representation of the divine.

Science.gov (United States)

Meier, Brian P; Hauser, David J; Robinson, Michael D; Friesen, Chris Kelland; Schjeldahl, Katie

2007-11-01

"God" and "Devil" are abstract concepts often linked to vertical metaphors (e.g., "glory to God in the highest," "the Devil lives down in hell"). It is unknown, however, whether these metaphors simply aid communication or implicate a deeper mode of concept representation. In 6 experiments, the authors examined the extent to which the vertical dimension is used in noncommunication contexts involving God and the Devil. Experiment 1 established that people have implicit associations between God-Devil and up-down. Experiment 2 revealed that people encode God-related concepts faster if presented in a high (vs. low) vertical position. Experiment 3 found that people's memory for the vertical location of God- and Devil-like images showed a metaphor-consistent bias (up for God; down for Devil). Experiments 4, 5a, and 5b revealed that people rated strangers as more likely to believe in God when their images appeared in a high versus low vertical position, and this effect was independent of inferences related to power and likability. These robust results reveal that vertical perceptions are invoked when people access divinity-related cognitions. (c) 2007 APA, all rights reserved.

Nurse leaders' perceptions of the ethical recruitment of study subjects in clinical research.

Science.gov (United States)

Nurmi, Sanna-Maria; Pietilä, Anna-Maija; Kangasniemi, Mari; Halkoaho, Arja

2015-11-01

The aim of this study was to describe nurse leaders' perceptions of ethical recruitment in clinical research. Nurse leaders are expected to get involved in clinical research, but there are few studies that focus on their role, particularly the ethical issues. Qualitative data were collected from ten nurse leaders using thematic one-to-one interviews and analysed with content analysis. Nurse leaders considered clinical research at their workplace in relation to the key issues that enabled ethical recruitment of study subjects in clinical research. These were: early information and collaboration for incorporating clinical research in everyday work, an opportune and peaceful recruitment moment and positive research culture. Getting involved in clinical research is part of the nurse leader's professional responsibility in current health care. They have an essential role to play in ensuring that recruitment is ethical and that the dignity of study subjects is maintained. The duty of nurse leaders is to maintain good contact with other collaborators and to ensure good conditions for implementing clinical research at their site. This requires a comprehensive understanding of the overall situation on their wards. Implementing clinical research requires careful planning, together with educating, supporting and motivating nursing staff. © 2014 John Wiley & Sons Ltd.

Brain mechanisms for simple perception and bistable perception.

Science.gov (United States)

Wang, Megan; Arteaga, Daniel; He, Biyu J

2013-08-27

When faced with ambiguous sensory inputs, subjective perception alternates between the different interpretations in a stochastic manner. Such multistable perception phenomena have intrigued scientists and laymen alike for over a century. Despite rigorous investigations, the underlying mechanisms of multistable perception remain elusive. Recent studies using multivariate pattern analysis revealed that activity patterns in posterior visual areas correlate with fluctuating percepts. However, increasing evidence suggests that vision--and perception at large--is an active inferential process involving hierarchical brain systems. We applied searchlight multivariate pattern analysis to functional magnetic resonance imaging signals across the human brain to decode perceptual content during bistable perception and simple unambiguous perception. Although perceptually reflective activity patterns during simple perception localized predominantly to posterior visual regions, bistable perception involved additionally many higher-order frontoparietal and temporal regions. Moreover, compared with simple perception, both top-down and bottom-up influences were dramatically enhanced during bistable perception. We further studied the intermittent presentation of ambiguous images--a condition that is known to elicit perceptual memory. Compared with continuous presentation, intermittent presentation recruited even more higher-order regions and was accompanied by further strengthened top-down influences but relatively weakened bottom-up influences. Taken together, these results strongly support an active top-down inferential process in perception.

Complex-enhanced chaotic signals with time-delay signature suppression based on vertical-cavity surface-emitting lasers subject to chaotic optical injection

Science.gov (United States)

Chen, Jianjun; Duan, Yingni; Zhong, Zhuqiang

2018-03-01

A chaotic system is constructed on the basis of vertical-cavity surface-emitting lasers (VCSELs), where a slave VCSEL subject to chaotic optical injection (COI) from a master VCSEL with the external feedback. The complex degree (CD) and time-delay signature (TDS) of chaotic signals generated by this chaotic system are investigated numerically via permutation entropy (PE) and self-correlation function (SF) methods, respectively. The results show that, compared with master VCSEL subject to optical feedback, complex-enhanced chaotic signals with TDS suppression can be achieved for S-VCSEL subject to COI. Meanwhile, the influences of several controllable parameters on the evolution maps of CD of chaotic signals are carefully considered. It is shown that the CD of chaotic signals for S-VCSEL is always higher than that for M-VCSEL due to the CIO effect. The TDS of chaotic signals can be significantly suppressed by choosing the reasonable parameters in this system. Furthermore, TDS suppression and high CD chaos can be obtained simultaneously in the specific parameter ranges. The results confirm that this chaotic system may effectively improve the security of a chaos-based communication scheme.

P1-19: Horizontal Vertical Illusion by Touch

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Yoshinari Kinoshita

2012-10-01

Full Text Available Revesz (1934 Zeitschrift fur PsychologieBd. 1, Kap 20 and Bean (1938 Journal of Experimental Psychology 22 283–289. reported almost all the geometrical optical illusions existed in a tactual mode. Such a study can examine theories of visual illusions with modality-free theories. A number of articles have been devoted to the theory that repeated judgments decline the magnitude of visual illusion. In the current study, we examine whether repeated judgments decline the magnitude of geometrical haptic illusion. The Fick illusion (i.e., a horizontal vertical illusion was investigated. A graphics Braille display with 32×48 dots was used to present an inverted T haptically without vision. The horizontal line was consistently 49.2 mm long, and the vertical line was varied in each trial. Three subjects with normal sight participated. They judged which line was longer than the other. The point of subjective equality at which the subject perceives the two lines to be the same was measured using the method of constant stimuli. In the first session the mean PSE was about 13%; to compensate for the illusion, the vertical line must be set physically shorter than the horizontal line. We found that repeated judgments produced a reduction in illusion magnitude and dissolved the illusion entirely.

The role of vertical conflict in the relationship between leader self-enhancement and leader performance

NARCIS (Netherlands)

van der Kam, Niels A.; Janssen, Onne; van der Vegt, Geert; Stoker, Janka I.

Although studies have shown that inflated self-perceptions of transformational leadership behavior negatively affect leader performance, insight into the underlying processes explaining this relationship is lacking. The current study addresses this gap by identifying vertical conflict between

How do visual and postural cues combine for self-tilt perception during slow pitch rotations?

Science.gov (United States)

Scotto Di Cesare, C; Buloup, F; Mestre, D R; Bringoux, L

2014-11-01

Self-orientation perception relies on the integration of multiple sensory inputs which convey spatially-related visual and postural cues. In the present study, an experimental set-up was used to tilt the body and/or the visual scene to investigate how these postural and visual cues are integrated for self-tilt perception (the subjective sensation of being tilted). Participants were required to repeatedly rate a confidence level for self-tilt perception during slow (0.05°·s(-1)) body and/or visual scene pitch tilts up to 19° relative to vertical. Concurrently, subjects also had to perform arm reaching movements toward a body-fixed target at certain specific angles of tilt. While performance of a concurrent motor task did not influence the main perceptual task, self-tilt detection did vary according to the visuo-postural stimuli. Slow forward or backward tilts of the visual scene alone did not induce a marked sensation of self-tilt contrary to actual body tilt. However, combined body and visual scene tilt influenced self-tilt perception more strongly, although this effect was dependent on the direction of visual scene tilt: only a forward visual scene tilt combined with a forward body tilt facilitated self-tilt detection. In such a case, visual scene tilt did not seem to induce vection but rather may have produced a deviation of the perceived orientation of the longitudinal body axis in the forward direction, which may have lowered the self-tilt detection threshold during actual forward body tilt. Copyright © 2014 Elsevier B.V. All rights reserved.

Perception and environmental education about mangrove ecosystem improving sciences and biology subjects in public school at Recife, PE

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Lauro Lopes Rodrigues

2008-01-01

Full Text Available This work was developed with the aim to identify the perceptions of the students from a school about the mangrove ecosystem, using didactic and natural elements available to do an environmental education action. The previous perception of the students on the ecosystem was evaluated by means of a questionnaire, followed of a theoretical exposition, complemented with a visit to a conserved mangrove (Paripe River, Itamaracá and another impacted (Jiquiá River, Recife, near to the school, being applied new questionnaires to evaluate their conceptions and the academic strategies. The students demonstrated a relative previous knowledge on the mangrove and the educative action showed effectiveness in the transference of the ecological concepts about the ecosystem, using the method of incorporate their daily knowledge to stimulate them to know the scientific side of the subject, ending with the development of ecologic conscience.

Subjective perception of cocaine reward in mice assessed by a single exposure place preference (sePP) paradigm

DEFF Research Database (Denmark)

Runegaard, Annika H.; Jensen, Kathrine Louise; Dencker, Ditte

2017-01-01

-related behavior. Comparison with existing methods In rodents, the rewarding effects of drugs have often been assessed in self-administration or place preference paradigms; both involving repeated drug exposure and weeks of training and testing. New method Our investigation describes a valid approach to assess....... The sePP protocol allows further dissection of the mechanism and influence of initial cocaine exposure on subsequent drug-related behaviors by including extinction and reinstatement. The lack of sePP in female mice may reflect a biologically relevant sex difference in the initial subjective perception...

Treatment timing for an orthopedic approach to patients with increased vertical dimension.

Science.gov (United States)

Baccetti, Tiziano; Franchi, Lorenzo; Schulz, Scott O; McNamara, James A

2008-01-01

The aim of this study was to investigate the role of treatment timing on the effectiveness of vertical-pull chincup (V-PCC) therapy in conjunction with a bonded rapid maxillary expander (RME) in growing subjects with mild-to-severe hyperdivergent facial patterns. The records of 39 subjects treated with a bonded RME combined with a V-PCC were compared with 29 untreated subjects with similar vertical skeletal disharmonies. Lateral cephalograms were analyzed before (T1) and after treatment or observation (T2). Both the treated and the untreated samples were divided into prepubertal and pubertal groups on the basis of cervical vertebral maturation (prepubertal treated group, 21 subjects; pubertal treated group, 18 subjects; prepubertal control group, 15 subjects; pubertal control group, 14 subjects). Mean change differences from T2 to T1 were compared in the 2 prepubertal and the 2 pubertal groups with independent-sample t tests. No statistically significant differences between the 2 prepubertal groups were found for any cephalometric skeletal measures from T1 to T2. When compared with the untreated pubertal sample, the group treated with the RME and V-PCC at puberty showed a statistically significant reduction in the inclination of the mandibular plane to the Frankfort horizontal (-2.2 mm), a statistically significant reduction in the inclination of the condylar axis to the mandibular plane (-2.2 degrees), and statistically significant supplementary growth of the mandibular ramus (1.7 mm). Treatment of increased vertical dimension with the RME and V-PCC protocol appears to produce better results during the pubertal growth spurt than before puberty, although the absolute amount of correction in the vertical skeletal parameters is limited.

Self-motion perception and vestibulo-ocular reflex during whole body yaw rotation in standing subjects: the role of head position and neck proprioception.

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Panichi, Roberto; Botti, Fabio Massimo; Ferraresi, Aldo; Faralli, Mario; Kyriakareli, Artemis; Schieppati, Marco; Pettorossi, Vito Enrico

2011-04-01

Self-motion perception and vestibulo-ocular reflex (VOR) were studied during whole body yaw rotation in the dark at different static head positions. Rotations consisted of four cycles of symmetric sinusoidal and asymmetric oscillations. Self-motion perception was evaluated by measuring the ability of subjects to manually track a static remembered target. VOR was recorded separately and the slow phase eye position (SPEP) was computed. Three different head static yaw deviations (active and passive) relative to the trunk (0°, 45° to right and 45° to left) were examined. Active head deviations had a significant effect during asymmetric oscillation: the movement perception was enhanced when the head was kept turned toward the side of body rotation and decreased in the opposite direction. Conversely, passive head deviations had no effect on movement perception. Further, vibration (100 Hz) of the neck muscles splenius capitis and sternocleidomastoideus remarkably influenced perceived rotation during asymmetric oscillation. On the other hand, SPEP of VOR was modulated by active head deviation, but was not influenced by neck muscle vibration. Through its effects on motion perception and reflex gain, head position improved gaze stability and enhanced self-motion perception in the direction of the head deviation. Copyright © 2010 Elsevier B.V. All rights reserved.

ZAG-Otolith: Modification of Otolith-Ocular Reflexes, Motion Perception and Manual Control during Variable Radius Centrifugation Following Space Flight

Science.gov (United States)

Wood, S. J.; Clarke, A. H.; Rupert, A. H.; Harm, D. L.; Clement, G. R.

2009-01-01

Two joint ESA-NASA studies are examining changes in otolith-ocular reflexes and motion perception following short duration space flights, and the operational implications of post-flight tilt-translation ambiguity for manual control performance. Vibrotactile feedback of tilt orientation is also being evaluated as a countermeasure to improve performance during a closed-loop nulling task. METHODS. Data is currently being collected on astronaut subjects during 3 preflight sessions and during the first 8 days after Shuttle landings. Variable radius centrifugation is utilized to elicit otolith reflexes in the lateral plane without concordant roll canal cues. Unilateral centrifugation (400 deg/s, 3.5 cm radius) stimulates one otolith positioned off-axis while the opposite side is centered over the axis of rotation. During this paradigm, roll-tilt perception is measured using a subjective visual vertical task and ocular counter-rolling is obtained using binocular video-oculography. During a second paradigm (216 deg/s, otolith-mediated reflexes correspond to one's ability to perform closed-loop nulling tasks following G-transitions, and whether manual control performance can be improved with vibrotactile feedback of orientation.

Organizational Justice Perception According to Generations

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Zeki YÜKSEKBİLGİLİ

2015-12-01

Full Text Available Although there are many different researches on the subject of organizational justice, there is no research on organizational justice perception according to generations. In this study, the research subject is defined if there is a difference on the perception of organizational justice between x and y generations. After a conduct of 430 surveys the Organizational Justice Scale is used. As a result, it is proved that there is no significant difference between the organizational justice perceptions according to generations

Vertical compared with transverse incisions in abdominal surgery

DEFF Research Database (Denmark)

Grantcharov, T P; Rosenberg, J

2001-01-01

, and late complications (incisional hernia). RESULTS: Eleven randomised controlled trials and seven retrospective studies were identified. The transverse incision offers as good an access to most intra-abdominal structures as a vertical incision. The transverse incision results in significantly less......OBJECTIVE: To reach an evidence-based consensus on the relative merits of vertical and transverse laparotomy incisions. DESIGN: Review of all published randomised controlled trials that compared the postoperative complications after the two main types of abdominal incisions, vertical and transverse....... SETTING: Teaching hospital, Denmark. SUBJECTS: Patients undergoing open abdominal operations. INTERVENTIONS: For some of the variables (burst abdomen and incisional hernia) it was considered adequate to include retrospective studies. Studies were identified through Medline, Cochrane library, Embase...

Determinations of vertical stroke V{sub cb} vertical stroke and vertical stroke V{sub ub} vertical stroke from baryonic Λ{sub b} decays

Energy Technology Data Exchange (ETDEWEB)

Hsiao, Y.K. [Shanxi Normal University, School of Physics and Information Engineering, Linfen (China); National Tsing Hua University, Department of Physics, Hsinchu (China); Geng, C.Q. [Shanxi Normal University, School of Physics and Information Engineering, Linfen (China); National Tsing Hua University, Department of Physics, Hsinchu (China); Hunan Normal University, Synergetic Innovation Center for Quantum Effects and Applications (SICQEA), Changsha (China)

2017-10-15

We present the first attempt to extract vertical stroke V{sub cb} vertical stroke from the Λ{sub b} → Λ{sub c}{sup +}l anti ν{sub l} decay without relying on vertical stroke V{sub ub} vertical stroke inputs from the B meson decays. Meanwhile, the hadronic Λ{sub b} → Λ{sub c}M{sub (c)} decays with M = (π{sup -},K{sup -}) and M{sub c} =(D{sup -},D{sup -}{sub s}) measured with high precisions are involved in the extraction. Explicitly, we find that vertical stroke V{sub cb} vertical stroke =(44.6 ± 3.2) x 10{sup -3}, agreeing with the value of (42.11 ± 0.74) x 10{sup -3} from the inclusive B → X{sub c}l anti ν{sub l} decays. Furthermore, based on the most recent ratio of vertical stroke V{sub ub} vertical stroke / vertical stroke V{sub cb} vertical stroke from the exclusive modes, we obtain vertical stroke V{sub ub} vertical stroke = (4.3 ± 0.4) x 10{sup -3}, which is close to the value of (4.49 ± 0.24) x 10{sup -3} from the inclusive B → X{sub u}l anti ν{sub l} decays. We conclude that our determinations of vertical stroke V{sub cb} vertical stroke and vertical stroke V{sub ub} vertical stroke favor the corresponding inclusive extractions in the B decays. (orig.)

Novelty enhances visual perception.

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Judith Schomaker

Full Text Available The effects of novelty on low-level visual perception were investigated in two experiments using a two-alternative forced-choice tilt detection task. A target, consisting of a Gabor patch, was preceded by a cue that was either a novel or a familiar fractal image. Participants had to indicate whether the Gabor stimulus was vertically oriented or slightly tilted. In the first experiment tilt angle was manipulated; in the second contrast of the Gabor patch was varied. In the first, we found that sensitivity was enhanced after a novel compared to a familiar cue, and in the second we found sensitivity to be enhanced for novel cues in later experimental blocks when participants became more and more familiarized with the familiar cue. These effects were not caused by a shift in the response criterion. This shows for the first time that novel stimuli affect low-level characteristics of perception. We suggest that novelty can elicit a transient attentional response, thereby enhancing perception.

Novelty enhances visual perception.

Science.gov (United States)

Schomaker, Judith; Meeter, Martijn

2012-01-01

The effects of novelty on low-level visual perception were investigated in two experiments using a two-alternative forced-choice tilt detection task. A target, consisting of a Gabor patch, was preceded by a cue that was either a novel or a familiar fractal image. Participants had to indicate whether the Gabor stimulus was vertically oriented or slightly tilted. In the first experiment tilt angle was manipulated; in the second contrast of the Gabor patch was varied. In the first, we found that sensitivity was enhanced after a novel compared to a familiar cue, and in the second we found sensitivity to be enhanced for novel cues in later experimental blocks when participants became more and more familiarized with the familiar cue. These effects were not caused by a shift in the response criterion. This shows for the first time that novel stimuli affect low-level characteristics of perception. We suggest that novelty can elicit a transient attentional response, thereby enhancing perception.

Long-term effects of serial anodal tDCS on motion perception in subjects with occipital stroke measured in the unaffected visual hemifield

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Manuel C Olma

2013-06-01

Full Text Available Transcranial direct current stimulation (tDCS is a novel neuromodulatory tool that has seen early transition to clinical trials, although the high variability of these findings necessitates further studies in clincally-relevant populations. The majority of evidence into effects of repeated tDCS is based on research in the human motor system, but it is unclear whether the long-term effects of serial tDCS are motor-specific or transferable to other brain areas. This study aimed to examine whether serial anodal tDCS over the visual cortex can exogenously induce long-term neuroplastic changes in the visual cortex. However, when the visual cortex is affected by a cortical lesion, up-regulated endogenous neuroplastic adaptation processes may alter the susceptibility to tDCS. To this end, motion perception was investigated in the unaffected hemifield of subjects with unilateral visual cortex lesions. Twelve subjects with occipital ischaemic lesions participated in a within-subject, sham-controlled, double-blind study. MRI-registered sham or anodal tDCS (1.5 mA, 20 minutes was applied on five consecutive days over the visual cortex. Motion perception was tested before and after stimulation sessions and at 14- and 28-day follow-up. After a 16-day interval an identical study block with the other stimulation condition (anodal or sham tDCS followed. Serial anodal tDCS over the visual cortex resulted in an improvement in motion perception, a function attributed to MT/V5. This effect was still measurable at 14- and 28-day follow-up measurements. Thus, this may represent evidence for long-term tDCS-induced plasticity and has implications for the design of studies examining the time course of tDCS effects in both the visual and motor systems.

Otolith signals contribute to inter-individual differences in the perception of gravity-centered space.

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Cian, C; Barraud, P A; Paillard, A C; Hidot, S; Denise, P; Ventre-Dominey, J

2014-03-01

The aim of the present study was to investigate (1) the relative contribution of the egocentric reference as well as body orientation perception to visual horizon percept during tilt or during increased gravito-inertial acceleration (GiA, hypergravity environment) conditions and (2) the role of vestibular signals in the inter-individual differences observed in these perceptual modalities. Perceptual estimates analysis showed that backward tilt induced (1) an elevation of the visual horizon, (2) an elevation of the egocentric estimation (visual straight ahead) and (3) an overestimation of body tilt. The increase in the magnitude of GiA induced (1) a lowering of the apparent horizon, (2) a lowering of the straight ahead and (3) a perception of backward tilt. Overall, visual horizon percept can be expressed as the combination of body orientation perception and egocentric estimation. When assessing otolith reactivity using off-vertical axis rotation (OVAR), only visual egocentric estimation was significantly correlated with horizontal OVAR performance. On the one hand, we found a correlation between a low modulation amplitude of the otolith responses and straight ahead accuracy when the head axis was tilted relative to gravity. On the other hand, the bias of otolith responses was significantly correlated with straight ahead accuracy when subjects were submitted to an increase in the GiA. Thus, straight ahead sense would be dependent to some extent to otolith function. These results are discussed in terms of the contribution of otolith inputs in the overall multimodal integration subtending spatial constancy.

Face perception is tuned to horizontal orientation in the N170 time window.

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Jacques, Corentin; Schiltz, Christine; Goffaux, Valerie

2014-02-07

The specificity of face perception is thought to reside both in its dramatic vulnerability to picture-plane inversion and its strong reliance on horizontally oriented image content. Here we asked when in the visual processing stream face-specific perception is tuned to horizontal information. We measured the behavioral performance and scalp event-related potentials (ERP) when participants viewed upright and inverted images of faces and cars (and natural scenes) that were phase-randomized in a narrow orientation band centered either on vertical or horizontal orientation. For faces, the magnitude of the inversion effect (IE) on behavioral discrimination performance was significantly reduced for horizontally randomized compared to vertically or nonrandomized images, confirming the importance of horizontal information for the recruitment of face-specific processing. Inversion affected the processing of nonrandomized and vertically randomized faces early, in the N170 time window. In contrast, the magnitude of the N170 IE was much smaller for horizontally randomized faces. The present research indicates that the early face-specific neural representations are preferentially tuned to horizontal information and offers new perspectives for a description of the visual information feeding face-specific perception.

Patients with migraine correctly estimate the visual verticality.

Science.gov (United States)

Crevits, Luc; Vanacker, Leen; Verraes, Anouk

2012-05-01

We wanted to study otolith function by measuring the static subjective visual vertical (SVV) in migraine patients and in controls with and without kinetosis (motion sickness). Forty-seven patients with moderately severe migraine and 96 healthy controls were enrolled. Using a questionnaire, persons with kinetosis were identified. The SVV test was performed in a totally dark room. Subjects wore a stiffneck to stabilize the head in an erect position. They were required to adjust an infrared line to the gravitational vertical with a hand-held infrared remote controlled potentiometer. The deviation of SVV in the group of migraine patients was not significantly different from that of controls, regardless of whether an aura was associated. SVV was not significantly influenced by the presence of dizziness/non specific vertigo or kinetosis. Patients with moderately severe migraine under prophylactic medication correctly estimate the visual verticality in the headache-free period. It is suggested that a deviation of SVV in a headache-free migraine patient may not be attributed to his migraine disorder as such regardless whether kinetosis is associated. Copyright © 2011 Elsevier B.V. All rights reserved.

NASA-Ames vertical gun

Science.gov (United States)

Schultz, P. H.

1984-01-01

A national facility, the NASA-Ames vertical gun range (AVGR) has an excellent reputation for revealing fundamental aspects of impact cratering that provide important constraints for planetary processes. The current logistics in accessing the AVGR, some of the past and ongoing experimental programs and their relevance, and the future role of this facility in planetary studies are reviewed. Publications resulting from experiments with the gun (1979 to 1984) are listed as well as the researchers and subjects studied.

Simulated self-motion in a visual gravity field: sensitivity to vertical and horizontal heading in the human brain.

Science.gov (United States)

Indovina, Iole; Maffei, Vincenzo; Pauwels, Karl; Macaluso, Emiliano; Orban, Guy A; Lacquaniti, Francesco

2013-05-01

Multiple visual signals are relevant to perception of heading direction. While the role of optic flow and depth cues has been studied extensively, little is known about the visual effects of gravity on heading perception. We used fMRI to investigate the contribution of gravity-related visual cues on the processing of vertical versus horizontal apparent self-motion. Participants experienced virtual roller-coaster rides in different scenarios, at constant speed or 1g-acceleration/deceleration. Imaging results showed that vertical self-motion coherent with gravity engaged the posterior insula and other brain regions that have been previously associated with vertical object motion under gravity. This selective pattern of activation was also found in a second experiment that included rectilinear motion in tunnels, whose direction was cued by the preceding open-air curves only. We argue that the posterior insula might perform high-order computations on visual motion patterns, combining different sensory cues and prior information about the effects of gravity. Medial-temporal regions including para-hippocampus and hippocampus were more activated by horizontal motion, preferably at constant speed, consistent with a role in inertial navigation. Overall, the results suggest partially distinct neural representations of the cardinal axes of self-motion (horizontal and vertical). Copyright © 2013 Elsevier Inc. All rights reserved.

Music, emotion, and time perception: the influence of subjective emotional valence and arousal?

Science.gov (United States)

Droit-Volet, Sylvie; Ramos, Danilo; Bueno, José L. O.; Bigand, Emmanuel

2013-01-01

The present study used a temporal bisection task with short (2 s) stimulus durations to investigate the effect on time estimation of several musical parameters associated with emotional changes in affective valence and arousal. In order to manipulate the positive and negative valence of music, Experiments 1 and 2 contrasted the effect of musical structure with pieces played normally and backwards, which were judged to be pleasant and unpleasant, respectively. This effect of valence was combined with a subjective arousal effect by changing the tempo of the musical pieces (fast vs. slow) (Experiment 1) or their instrumentation (orchestral vs. piano pieces). The musical pieces were indeed judged more arousing with a fast than with a slow tempo and with an orchestral than with a piano timbre. In Experiment 3, affective valence was also tested by contrasting the effect of tonal (pleasant) vs. atonal (unpleasant) versions of the same musical pieces. The results showed that the effect of tempo in music, associated with a subjective arousal effect, was the major factor that produced time distortions with time being judged longer for fast than for slow tempi. When the tempo was held constant, no significant effect of timbre on the time judgment was found although the orchestral music was judged to be more arousing than the piano music. Nevertheless, emotional valence did modulate the tempo effect on time perception, the pleasant music being judged shorter than the unpleasant music. PMID:23882233

Music, Emotion and Time Perception: The influence of subjective emotional valence and arousal?

Directory of Open Access Journals (Sweden)

SYLVIE eDROIT-VOLET

2013-07-01

Full Text Available The present study used a temporal bisection task with short (< 2 s and long (> 2 s stimulus durations to investigate the effect on time estimation of several musical parameters associated with emotional changes in affective valence and arousal. In order to manipulate the positive and negative valence of music, Experiments 1 and 2 contrasted the effect of musical structure with pieces played normally and backwards, which were judged to be pleasant and unpleasant, respectively. This effect of valence was combined with a subjective arousal effect by changing the tempo of the musical pieces (fast vs. slow (Experiment 1 or their instrumentation (orchestral vs. piano pieces. The musical pieces were indeed judged more arousing with a fast than with a slow tempo and with an orchestral than with a piano timbre. In Experiment 3, affective valence was also tested by contrasting the effect of tonal (pleasant versus atonal (unpleasant versions of the same musical pieces. The results showed that the effect of tempo in music, associated with a subjective arousal effect, was the major factor that produced time distortions with time being judged longer for fast than for slow tempi. When the tempo was held constant, no significant effect of timbre on the time judgment was found although the orchestral music was judged to be more arousing than the piano music. Nevertheless, emotional valence did modulate the tempo effect on time perception, the pleasant music being judged shorter than the unpleasant music.

Music, emotion, and time perception: the influence of subjective emotional valence and arousal?

Science.gov (United States)

Droit-Volet, Sylvie; Ramos, Danilo; Bueno, José L O; Bigand, Emmanuel

2013-01-01

The present study used a temporal bisection task with short (2 s) stimulus durations to investigate the effect on time estimation of several musical parameters associated with emotional changes in affective valence and arousal. In order to manipulate the positive and negative valence of music, Experiments 1 and 2 contrasted the effect of musical structure with pieces played normally and backwards, which were judged to be pleasant and unpleasant, respectively. This effect of valence was combined with a subjective arousal effect by changing the tempo of the musical pieces (fast vs. slow) (Experiment 1) or their instrumentation (orchestral vs. piano pieces). The musical pieces were indeed judged more arousing with a fast than with a slow tempo and with an orchestral than with a piano timbre. In Experiment 3, affective valence was also tested by contrasting the effect of tonal (pleasant) vs. atonal (unpleasant) versions of the same musical pieces. The results showed that the effect of tempo in music, associated with a subjective arousal effect, was the major factor that produced time distortions with time being judged longer for fast than for slow tempi. When the tempo was held constant, no significant effect of timbre on the time judgment was found although the orchestral music was judged to be more arousing than the piano music. Nevertheless, emotional valence did modulate the tempo effect on time perception, the pleasant music being judged shorter than the unpleasant music.

Causal Inference in the Perception of Verticality.

Science.gov (United States)

de Winkel, Ksander N; Katliar, Mikhail; Diers, Daniel; Bülthoff, Heinrich H

2018-04-03

The perceptual upright is thought to be constructed by the central nervous system (CNS) as a vector sum; by combining estimates on the upright provided by the visual system and the body's inertial sensors with prior knowledge that upright is usually above the head. Recent findings furthermore show that the weighting of the respective sensory signals is proportional to their reliability, consistent with a Bayesian interpretation of a vector sum (Forced Fusion, FF). However, violations of FF have also been reported, suggesting that the CNS may rely on a single sensory system (Cue Capture, CC), or choose to process sensory signals based on inferred signal causality (Causal Inference, CI). We developed a novel alternative-reality system to manipulate visual and physical tilt independently. We tasked participants (n = 36) to indicate the perceived upright for various (in-)congruent combinations of visual-inertial stimuli, and compared models based on their agreement with the data. The results favor the CI model over FF, although this effect became unambiguous only for large discrepancies (±60°). We conclude that the notion of a vector sum does not provide a comprehensive explanation of the perception of the upright, and that CI offers a better alternative.

Induction of depressed and elated mood by music influences the perception of facial emotional expressions in healthy subjects.

Science.gov (United States)

Bouhuys, A L; Bloem, G M; Groothuis, T G

1995-04-04

The judgement of healthy subject rating the emotional expressions of a set of schematic drawn faces is validated (study 1) to examine the relationship between mood (depressed/elated) and judgement of emotional expressions of these faces (study 2). Study 1: 30 healthy subjects judged 12 faces with respect to the emotions they express (fear, happiness, anger, sadness, disgust, surprise, rejection and invitation). It was found that a particular face could reflect various emotions. All eight emotions were reflected in the set of faces and the emotions were consensually judged. Moreover, gender differences in judgement could be established. Study 2: In a cross-over design, 24 healthy subjects judged the faces after listening to depressing or elating music. The faces were subdivided in six 'ambiguous' faces (i.e., expressing similar amounts of positive and negative emotions) and six 'clear' faces (i.e., faces showing a preponderance of positive or negative emotions). In addition, these two types of faces were distinguished with respect to the intensity of emotions they express. 11 subjects who showed substantial differences in experienced depression after listening to the music were selected for further analysis. It was found that, when feeling more depressed, the subjects perceived more rejection/sadness in ambiguous faces (displaying less intensive emotions) and less invitation/happiness in clear faces. In addition, subjects saw more fear in clear faces that express less intensive emotions. Hence, results show a depression-related negative bias in the perception of facial displays.

Self-esteem, social support perception and seizure controllability perception in adolescents with epilepsy

Directory of Open Access Journals (Sweden)

Nathália F. Siqueira

2011-10-01

Full Text Available OBJECTIVE: Compare the self-esteem of adolescents with epilepsy and adolescents without epilepsy and relate it to social support and seizure controllability perception. METHOD: The study sample consisted: case participants (34 subjects attending the pediatric epilepsy clinic of University Hospital and control participants (30 subjects from public schools in Campinas-SP. The instruments utilized were: identification card with demographic and epilepsy data, a semi-structured interview on aspects of the disease, and a Self-Esteem Multidimensional Scale. RESULTS: There was no significant difference between the two groups but majority of adolescents with epilepsy presented higher self esteem rate, have knowledge about epilepsy, presented high levels of social support and seizure controllability perception. There was no significant relationship between social support and seizure controllability perception with self-esteem. CONCLUSION: Knowledge about epilepsy, social support such good controllability seizure perception seem are important contingencies for a better evaluation of self esteem in adolescents with epilepsy.

Students' perceptions of vertical and horizontal integration in a discipline-based dental school.

Science.gov (United States)

Postma, T C; White, J G

2017-05-01

Integration is a key concern in discipline-based undergraduate dental curricula. Therefore, this study compared feedback on integration from students who participated in different instructional designs in a Comprehensive Patient Care course. The study was conducted at the University of Pretoria (2009-2011). Third-year cohorts (Cohorts A, B and C) participated in pre-clinical case-based learning, whilst fourth-year cohorts (Cohorts D and E) received didactic teaching in Comprehensive Patient Care. Cohorts A, D and E practised clinical Comprehensive Patient Care in a discipline-based clinic. Cohort B conducted their Comprehensive Patient Care patient examinations in a dedicated facility supervised by dedicated faculty responsible to teach integration. Students had to indicate on visual analogue scales whether the way they were taught at the school helped them to integrate knowledge from the same (horizontal integration) and preceding (vertical integration) year of study. The end-points of the scales were defined as 'definitely' and 'not at all'. Analysis of variance (ANOVA) was employed to measure the differences between cohorts according to the year of study. Third-year case-based learning cohorts rated the horizontal integration close to 80/100 and vertical integration ranging from 64 to 71/100. In year four, Cohort B rated vertical and horizontal integration 9-15% higher (ANOVA, P horizontal integration 11-18% higher (ANOVA, P integration in the discipline-based undergraduate dental curriculum. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The Meaning of Terrace as Social Interaction Place in Vertical Kampung

Science.gov (United States)

Sihombing, Antony; Gumay Poetri, Nurul

2018-01-01

The pros and cons of vertical housing development in Jakarta make me intend to raise the issue of the vertical kampung. In the kampung, there are social spaces where people interact to create a culture of rukun and gotong-royong. It is the terrace which become a container of social interaction. The purpose of this study is to reveal the meaning of the terrace in social interaction in the vertical kampung and its influence when the terrace room is not presented in the vertical kampung. The lost meaning of kampung when terrace is not presented in vertical kampung can be known through cognitive maps. Cognitive maps are the methodologies used to gain a human perception or view of life experiences in a particular place. This study involved several families in West Jatinegara Rusunawa to find out how people looked at the terrace in their life while in Kampung Pulo. Based on the cognitive maps method that has been done by the respondents, the terrace referred to by the villagers is an open space where people can see and interact with each other. Social space in the form of terraces which is needed by the kampung dweller, in fact is not a terrace house which is used as a place to receive guests and as a barrier between the fence and the body of the house.

Dimensions of school climate: teachers' or principals' power styles and subjects' propensities to be climate vigilant as related to students' perceptions of satisfaction and of peers' abusive behavior.

Science.gov (United States)

Verhoek-Miller, Nancy; Miller, Duane I; Shirachi, Miyoko; Hoda, Nicholas

2002-08-01

Two studies investigated teachers' and principals' power styles as related to college students' retrospective ratings of satisfaction and peers' abusive behavior. One study also investigated retrospective self-perception as related to students' sensitivity to the occurrence of physical and psychological abuse in the school environment. Among the findings were positive correlations between subjects' perceptions that their typical elementary school teacher used referent, legitimate, or expert power styles and subjects' reported satisfaction with their elementary school experience. Small but statistically significant correlations were found suggesting that principals' power style was weakly associated with ratings of psychological abuse in elementary school and physical abuse in middle school. Also, students who rated themselves as intelligent, sensitive, attractive, and depressive had higher ratings of perceived psychological and physical abuse at school. It was concluded that parameters of leaders' power styles and subjects' vigilance might be useful for understanding school climates. Experimentally designed studies are required.

Dynamics of context and psychological well-being : the role of subjective health perceptions, personality factors and spirituality / Qambeshile Michael Temane

OpenAIRE

Temane, Qambeshile Michael

2006-01-01

There is a lacuna in the field of positive psychology as far as the conceptualisation of influences of environmental contexts on psychological well-being is concerned, and there is also a lack of credible empirical findings on the dynamics of processes involved. The aim of the current study was to test various models on the possible mediating role of subjective perceptions of health, personality factors and spirituality in the dynamics of context and psychological well-being. ...

Making Time for Nature: Visual Exposure to Natural Environments Lengthens Subjective Time Perception and Reduces Impulsivity.

Directory of Open Access Journals (Sweden)

Meredith S Berry

Full Text Available Impulsivity in delay discounting is associated with maladaptive behaviors such as overeating and drug and alcohol abuse. Researchers have recently noted that delay discounting, even when measured by a brief laboratory task, may be the best predictor of human health related behaviors (e.g., exercise currently available. Identifying techniques to decrease impulsivity in delay discounting, therefore, could help improve decision-making on a global scale. Visual exposure to natural environments is one recent approach shown to decrease impulsive decision-making in a delay discounting task, although the mechanism driving this result is currently unknown. The present experiment was thus designed to evaluate not only whether visual exposure to natural (mountains, lakes relative to built (buildings, cities environments resulted in less impulsivity, but also whether this exposure influenced time perception. Participants were randomly assigned to either a natural environment condition or a built environment condition. Participants viewed photographs of either natural scenes or built scenes before and during a delay discounting task in which they made choices about receiving immediate or delayed hypothetical monetary outcomes. Participants also completed an interval bisection task in which natural or built stimuli were judged as relatively longer or shorter presentation durations. Following the delay discounting and interval bisection tasks, additional measures of time perception were administered, including how many minutes participants thought had passed during the session and a scale measurement of whether time "flew" or "dragged" during the session. Participants exposed to natural as opposed to built scenes were less impulsive and also reported longer subjective session times, although no differences across groups were revealed with the interval bisection task. These results are the first to suggest that decreased impulsivity from exposure to natural as

Neck proprioception shapes body orientation and perception of motion

Directory of Open Access Journals (Sweden)

Vito Enrico Pettorossi

2014-11-01

Full Text Available This review article deals with some effects of neck muscle proprioception on human balance, gait trajectory, subjective straight-ahead, and self-motion perception. These effects are easily observed during neck muscle vibration, a strong stimulus for the spindle primary afferent fibers.We first remind the early findings on human balance, gait trajectory, subjective straight-ahead, induced by limb and neck muscle vibration. Then, more recent findings on self-motion perception of vestibular origin are described. The use of a vestibular asymmetric yaw-rotation stimulus for emphasizing the proprioceptive modulation of motion perception from the neck is mentioned. In addition, an attempt has been made to conjointly discuss the effects of unilateral neck proprioception on motion perception, subjective straight-ahead and walking trajectory.Neck vibration also induces persistent aftereffects on the subjective straight-ahead and on self-motion perception of vestibular origin. These perceptive effects depend on intensity, duration, side of the conditioning vibratory stimulation, and on muscle status. These effects can be maintained for hours when prolonged high-frequency vibration is superimposed on muscle contraction. Overall, this brief outline emphasizes the contribution of neck muscle inflow to the construction and fine-tuning of perception of body orientation and motion. Furthermore, it indicates that tonic neck proprioceptive input may induce persistent influences on the subject's mental representation of space. These plastic changes might adapt motion sensitiveness to lasting or permanent head positional or motor changes.

Attractor hopping between polarization dynamical states in a vertical-cavity surface-emitting laser subject to parallel optical injection

Science.gov (United States)

Denis-le Coarer, Florian; Quirce, Ana; Valle, Angel; Pesquera, Luis; Rodríguez, Miguel A.; Panajotov, Krassimir; Sciamanna, Marc

2018-03-01

We present experimental and theoretical results of noise-induced attractor hopping between dynamical states found in a single transverse mode vertical-cavity surface-emitting laser (VCSEL) subject to parallel optical injection. These transitions involve dynamical states with different polarizations of the light emitted by the VCSEL. We report an experimental map identifying, in the injected power-frequency detuning plane, regions where attractor hopping between two, or even three, different states occur. The transition between these behaviors is characterized by using residence time distributions. We find multistability regions that are characterized by heavy-tailed residence time distributions. These distributions are characterized by a -1.83 ±0.17 power law. Between these regions we find coherence enhancement of noise-induced attractor hopping in which transitions between states occur regularly. Simulation results show that frequency detuning variations and spontaneous emission noise play a role in causing switching between attractors. We also find attractor hopping between chaotic states with different polarization properties. In this case, simulation results show that spontaneous emission noise inherent to the VCSEL is enough to induce this hopping.

Understanding Latina/o Students' Meaning in Life, Spirituality, and Subjective Happiness

Science.gov (United States)

Cavazos Vela, Javier; Castro, Veronica; Cavazos, Leticia; Cavazos, Michelle; Gonzalez, Stacey Lee

2015-01-01

One-hundred nineteen Latina/o college students provided perceptions of presence of meaning in life, search for meaning in life, daily spiritual experiences, and subjective happiness. Perceptions of meaning in life and daily spiritual experiences were significant predictors of subjective happiness. A discussion regarding the importance of these…

Subjective Perception of Sports Performance, Training, Sleep and Dietary Patterns of Malaysian Junior Muslim Athletes during Ramadan Intermittent Fasting.

Science.gov (United States)

Singh, Rabindarjeet; Hwa, Ooi Cheong; Roy, Jolly; Jin, Chai Wen; Ismail, Siti Musyrifah; Lan, Mohamad Faizal; Hiong, Loo Lean; Aziz, Abdul-Rashid

2011-09-01

To examine the subjective perception of daily acute fasting on sports performance, training, sleep and dietary patterns of Muslim athletes during the Ramadan month. Seven hundred and thirty-four (411 male and 323 female) Malaysian Junior-level Muslim athletes (mean age 16.3 ± 2.6 y) participated in the survey which was designed to establish the personal perception of their sport performance, sleep pattern, food and fluid intake during Ramadan fasting. The survey was conducted during and immediately after the month of Ramadan in 2009. Twenty-four percent of the athletes perceived that there was an adverse effect of the Ramadan fast on their sporting performance and 29.3% reported that quality of training during Ramadan was also negatively influenced. Majority (48.2%) of the athletes stated that Ramadan fasting did not affect their normal sleep pattern but 66.6% of them complained of sleepiness during the daytime. Half of the athletes (41.4%) maintained the caloric intake during Ramadan as they normally would with the majority of them (76.2%) reporting that they consumed more fluids during Ramadan. Overall, Malaysian Junior-level Muslim athletes showed diverse views in their perception of changes in their training, sleep and dietary patterns during Ramadan fast. These individual differences probably indicate differences in the athletes' adaptability and coping strategies during fasting and training in Ramadan.

Subjective Perception of Sports Performance, Training, Sleep and Dietary Patterns of Malaysian Junior Muslim Athletes during Ramadan Intermittent Fasting

Science.gov (United States)

Singh, Rabindarjeet; Hwa, Ooi Cheong; Roy, Jolly; Jin, Chai Wen; Ismail, Siti Musyrifah; Lan, Mohamad Faizal; Hiong, Loo Lean; Aziz, Abdul-Rashid

2011-01-01

Purpose To examine the subjective perception of daily acute fasting on sports performance, training, sleep and dietary patterns of Muslim athletes during the Ramadan month. Methods Seven hundred and thirty-four (411 male and 323 female) Malaysian Junior-level Muslim athletes (mean age 16.3 ± 2.6 y) participated in the survey which was designed to establish the personal perception of their sport performance, sleep pattern, food and fluid intake during Ramadan fasting. The survey was conducted during and immediately after the month of Ramadan in 2009. Results Twenty-four percent of the athletes perceived that there was an adverse effect of the Ramadan fast on their sporting performance and 29.3% reported that quality of training during Ramadan was also negatively influenced. Majority (48.2%) of the athletes stated that Ramadan fasting did not affect their normal sleep pattern but 66.6% of them complained of sleepiness during the daytime. Half of the athletes (41.4%) maintained the caloric intake during Ramadan as they normally would with the majority of them (76.2%) reporting that they consumed more fluids during Ramadan. Conclusions Overall, Malaysian Junior-level Muslim athletes showed diverse views in their perception of changes in their training, sleep and dietary patterns during Ramadan fast. These individual differences probably indicate differences in the athletes’ adaptability and coping strategies during fasting and training in Ramadan. PMID:22375236

Estimation of Vertical Ground Reaction Forces and Sagittal Knee Kinematics During Running Using Three Inertial Sensors

Directory of Open Access Journals (Sweden)

Frank J. Wouda

2018-03-01

Full Text Available Analysis of running mechanics has traditionally been limited to a gait laboratory using either force plates or an instrumented treadmill in combination with a full-body optical motion capture system. With the introduction of inertial motion capture systems, it becomes possible to measure kinematics in any environment. However, kinetic information could not be provided with such technology. Furthermore, numerous body-worn sensors are required for a full-body motion analysis. The aim of this study is to examine the validity of a method to estimate sagittal knee joint angles and vertical ground reaction forces during running using an ambulatory minimal body-worn sensor setup. Two concatenated artificial neural networks were trained (using data from eight healthy subjects to estimate the kinematics and kinetics of the runners. The first artificial neural network maps the information (orientation and acceleration of three inertial sensors (placed at the lower legs and pelvis to lower-body joint angles. The estimated joint angles in combination with measured vertical accelerations are input to a second artificial neural network that estimates vertical ground reaction forces. To validate our approach, estimated joint angles were compared to both inertial and optical references, while kinetic output was compared to measured vertical ground reaction forces from an instrumented treadmill. Performance was evaluated using two scenarios: training and evaluating on a single subject and training on multiple subjects and evaluating on a different subject. The estimated kinematics and kinetics of most subjects show excellent agreement (ρ>0.99 with the reference, for single subject training. Knee flexion/extension angles are estimated with a mean RMSE <5°. Ground reaction forces are estimated with a mean RMSE < 0.27 BW. Additionaly, peak vertical ground reaction force, loading rate and maximal knee flexion during stance were compared, however, no significant

Abdominal acupuncture reduces laser-evoked potentials in healthy subjects

DEFF Research Database (Denmark)

Pazzaglia, C.; Liguori, S.; Minciotti, I.

2015-01-01

Objective: Acupuncture is known to reduce clinical pain, although the exact mechanism is unknown. The aim of the current study was to investigate the effect of acupuncture on laser-evoked potential amplitudes and laser pain perception. Methods: In order to evaluate whether abdominal acupuncture...... is able to modify pain perception, 10 healthy subjects underwent a protocol in which laser-evoked potentials (LEPs) and laser pain perception were collected before the test (baseline), during abdominal acupuncture, and 15. min after needle removal. The same subjects also underwent a similar protocol...... in which, however, sham acupuncture without any needle penetration was used. Results: During real acupuncture, both N1 and N2/P2 amplitudes were reduced, as compared to baseline (p . < 0.01). The reduction lasted up to 15. min after needle removal. Furthermore, laser pain perception was reduced during...

Legal unbundling and auctions in vertically integrated (utilities) markets

Czech Academy of Sciences Publication Activity Database

van Koten, Silvester

2013-01-01

Roč. 36, č. 3 (2013), s. 543-573 ISSN 0929-1261 R&D Projects: GA MŠk LC542 Institutional support: RVO:67985998 Keywords : regulation * vertical integration * electricity markets Subject RIV: AH - Economics Impact factor: 0.330, year: 2013

The perception of probability.

Science.gov (United States)

Gallistel, C R; Krishan, Monika; Liu, Ye; Miller, Reilly; Latham, Peter E

2014-01-01

We present a computational model to explain the results from experiments in which subjects estimate the hidden probability parameter of a stepwise nonstationary Bernoulli process outcome by outcome. The model captures the following results qualitatively and quantitatively, with only 2 free parameters: (a) Subjects do not update their estimate after each outcome; they step from one estimate to another at irregular intervals. (b) The joint distribution of step widths and heights cannot be explained on the assumption that a threshold amount of change must be exceeded in order for them to indicate a change in their perception. (c) The mapping of observed probability to the median perceived probability is the identity function over the full range of probabilities. (d) Precision (how close estimates are to the best possible estimate) is good and constant over the full range. (e) Subjects quickly detect substantial changes in the hidden probability parameter. (f) The perceived probability sometimes changes dramatically from one observation to the next. (g) Subjects sometimes have second thoughts about a previous change perception, after observing further outcomes. (h) The frequency with which they perceive changes moves in the direction of the true frequency over sessions. (Explaining this finding requires 2 additional parametric assumptions.) The model treats the perception of the current probability as a by-product of the construction of a compact encoding of the experienced sequence in terms of its change points. It illustrates the why and the how of intermittent Bayesian belief updating and retrospective revision in simple perception. It suggests a reinterpretation of findings in the recent literature on the neurobiology of decision making. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Stretch-sensitive paresis and effort perception in hemiparesis.

Science.gov (United States)

Vinti, Maria; Bayle, Nicolas; Hutin, Emilie; Burke, David; Gracies, Jean-Michel

2015-08-01

In spastic paresis, stretch applied to the antagonist increases its inappropriate recruitment during agonist command (spastic co-contraction). It is unknown whether antagonist stretch: (1) also affects agonist recruitment; (2) alters effort perception. We quantified voluntary activation of ankle dorsiflexors, effort perception, and plantar flexor co-contraction during graded dorsiflexion efforts at two gastrocnemius lengths. Eighteen healthy (age 41 ± 13) and 18 hemiparetic (age 54 ± 12) subjects performed light, medium and maximal isometric dorsiflexion efforts with the knee flexed or extended. We determined dorsiflexor torque, Root Mean Square EMG and Agonist Recruitment/Co-contraction Indices (ARI/CCI) from the 500 ms peak voluntary agonist recruitment in a 5-s maximal isometric effort in tibialis anterior, soleus and medial gastrocnemius. Subjects retrospectively reported effort perception on a 10-point visual analog scale. During gastrocnemius stretch in hemiparetic subjects, we observed: (1) a 25 ± 7 % reduction of tibialis anterior voluntary activation (maximum reduction 98 %; knee extended vs knee flexed; p = 0.007, ANOVA); (2) an increase in dorsiflexion effort perception (p = 0.03, ANCOVA). Such changes did not occur in healthy subjects. Effort perception depended on tibialis anterior recruitment only (βARI(TA) = 0.61, p hemiparesis, voluntary ability to recruit agonist motoneurones is impaired--sometimes abolished--by antagonist stretch, a phenomenon defined here as stretch-sensitive paresis. In addition, spastic co-contraction increases effort perception, an additional incentive to evaluate and treat this phenomenon.

Exposure knowledge and risk perception of RF EMF

Directory of Open Access Journals (Sweden)

Frederik eFreudenstein

2015-01-01

Full Text Available The presented study is part of the EU Project LEXNET (Low EMF Exposure Future Networks, which deals among other things with the issue of whether a reduction of the radiofrequency (RF electro-magnetic fields (EMF exposure will result in more acceptance of wireless communication networks in the public sphere.We assume that the effects of any reduction of EMF exposure will depend on the subjective link between exposure perception and risk perception. Therefore we evaluated respondents’ risk perceptions of different RF EMF sources and their subjective knowledge about various exposure characteristics with regard to their impact on potential health risks. The results show that participants are more concerned about base stations than about all other RF EMF sources. Concerning the subjective exposure knowledge the results suggest that people have a quite appropriate impact model. The question how RF EMF risk perception is actually affected by the knowledge about the various exposure characteristics was tested in a linear regression analysis. The regression indicates that these features - except distance - do influence people’s general RF EMF risk perceptions. In addition, we analyzed the effect of the quality of exposure knowledge on RF EMF risk perception of various sources. The results show a tendency that better exposure knowledge leads to higher risk perception, especially for mobile phones. The study provides empirical support for models of the relationships between exposure perception and risk perception. It is not the aim to extrapolate these findings to the whole population because the samples are not exactly representative for the general public in the participating countries.

A neural interface provides long-term stable natural touch perception.

Science.gov (United States)

Tan, Daniel W; Schiefer, Matthew A; Keith, Michael W; Anderson, James Robert; Tyler, Joyce; Tyler, Dustin J

2014-10-08

Touch perception on the fingers and hand is essential for fine motor control, contributes to our sense of self, allows for effective communication, and aids in our fundamental perception of the world. Despite increasingly sophisticated mechatronics, prosthetic devices still do not directly convey sensation back to their wearers. We show that implanted peripheral nerve interfaces in two human subjects with upper limb amputation provided stable, natural touch sensation in their hands for more than 1 year. Electrical stimulation using implanted peripheral nerve cuff electrodes that did not penetrate the nerve produced touch perceptions at many locations on the phantom hand with repeatable, stable responses in the two subjects for 16 and 24 months. Patterned stimulation intensity produced a sensation that the subjects described as natural and without "tingling," or paresthesia. Different patterns produced different types of sensory perception at the same location on the phantom hand. The two subjects reported tactile perceptions they described as natural tapping, constant pressure, light moving touch, and vibration. Changing average stimulation intensity controlled the size of the percept area; changing stimulation frequency controlled sensation strength. Artificial touch sensation improved the subjects' ability to control grasping strength of the prosthesis and enabled them to better manipulate delicate objects. Thus, electrical stimulation through peripheral nerve electrodes produced long-term sensory restoration after limb loss. Copyright © 2014, American Association for the Advancement of Science.

Perception of facial expressions produced by configural relations

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V A Barabanschikov

2010-06-01

Full Text Available The authors discuss the problem of perception of facial expressions produced by configural features. Experimentally found configural features influence the perception of emotional expression of subjectively emotionless face. Classical results by E. Brunsvik related to perception of schematic faces are partly confirmed.

Determination of charge on vertically aligned particles in a complex plasma using laser excitations

CERN Document Server

Prior, N J; Samarian, A A

2003-01-01

Experimental studies on vertical oscillations of few particle vertical structures are described. One and two particle strings were subjected to two types of vertically driven oscillations. The first was electrode driven, which excites the structure as a whole, while the second was laser driven, which excites one particle in the structure only. The latter experiments are highly original, enabling us to excite two vertical resonances in our two particle structures. From the close agreement between our experimental data and theoretical model, several important physical parameters have been estimated, including the charge ratio and the Debye length.

Sands subjected to repetitive vertical loading under zero lateral strain: accumulation models, terminal densities, and settlement

KAUST Repository

Chong, Song Hun; Santamarina, Carlos

2016-01-01

). Repetitive vertical loading tests under zero lateral strain conditions are conducted using three different sands packed at initially low and high densities. Test results show that plastic strain accumulation for all sands and density conditions can

Soft soils reinforced by rigid vertical inclusions

Directory of Open Access Journals (Sweden)

Iulia-Victoria NEAGOE

2013-12-01

Full Text Available Reinforcement of soft soils by rigid vertical inclusions is an increasingly used technique over the last few years. The system consists of rigid or semi-rigid vertical inclusions and a granular platform for the loads transfer from the structure to the inclusions. This technique aims to reduce the differential settlements both at ground level as below the structure. Reinforcement by rigid inclusions is mainly used for foundation works for large commercial and industrial platforms, storage tanks, wastewater treatment plants, wind farms, bridges, roads, railway embankments. The subject is one of interest as it proves the recently concerns at international level in research and design; however, most studies deal more with the static behavior and less with the dynamic one.

Modification of Otolith-Ocular Reflexes, Motion Perception and Manual Control During Variable Radius Centrifugation Following Space Flight

Science.gov (United States)

Wood, Scott J.; Clarke, A. H.; Rupert, A. H.; Harm, D. L.; Clement, G. R.

2009-01-01

Two joint ESA-NASA studies are examining changes in otolith-ocular reflexes and motion perception following short duration space flights, and the operational implications of post-flight tilt-translation ambiguity for manual control performance. Vibrotactile feedback of tilt orientation is also being evaluated as a countermeasure to improve performance during a closed-loop nulling task. Data is currently being collected on astronaut subjects during 3 preflight sessions and during the first 8 days after Shuttle landings. Variable radius centrifugation is utilized to elicit otolith reflexes in the lateral plane without concordant roll canal cues. Unilateral centrifugation (400 deg/s, 3.5 cm radius) stimulates one otolith positioned off-axis while the opposite side is centered over the axis of rotation. During this paradigm, roll-tilt perception is measured using a subjective visual vertical task and ocular counter-rolling is obtained using binocular video-oculography. During a second paradigm (216 deg/s, less than 20 cm radius), the effects of stimulus frequency (0.15 - 0.6 Hz) are examined on eye movements and motion perception. A closed-loop nulling task is also performed with and without vibrotactile display feedback of chair radial position. Data collection is currently ongoing. Results to date suggest there is a trend for perceived tilt and translation amplitudes to be increased at the low and medium frequencies on landing day compared to pre-flight. Manual control performance is improved with vibrotactile feedback. One result of this study will be to characterize the variability (gain, asymmetry) in both otolith-ocular responses and motion perception during variable radius centrifugation, and measure the time course of post-flight recovery. This study will also address how adaptive changes in otolith-mediated reflexes correspond to one's ability to perform closed-loop nulling tasks following G-transitions, and whether manual control performance can be improved

Life role salience and subjective well-being among Macedonian employees: Does family-supportive organization perception moderate this relationship.

Science.gov (United States)

Blaževska Stoilkovska, Biljana; Šurbanovska, Orhideja; Fritzhand, Ana; Stojanoska Ivanova, Tatjana

2018-01-15

As many studies have shown, one of the most important tendencies of employees nowadays is to achieve work- life balance. Organizations should develop various activities and create supportive climate, within the framework of which employees will have opportunities to realize aforementioned goals which in turn would increase work productivity and work motivation. The aim of this paper was to examine how subjective well-being (life satisfaction and exhaustion) is associated with commitment to work and family roles under the conditions of strongly and weakly perceived organizational support for family life among health care professionals, teachers and bankers in Macedonia. Marriage duration and the number of children were introduced as control variables. This cross-sectional study was conducted on a sample of 198 full-time employed doctors, nurses, teachers and bankers. Research variables were assessed using self-reported measures/ questionnaires. Hierarchical multiple linear regression was performed for data analysis. It was revealed that occupational role commitment contributed to highly expressed life satisfaction, while exhaustion was predicted by marital role commitment. These relationships were stronger among surveyed employees who reported positive family-supportive organization perception, but tested moderation effect of this variable was not statistically significant. Findings demonstrated that family-supportive organization perception moderated association of the number of children with life satisfaction, that is, participants who perceived an organization as family-supportive and had more children were more satisfied with their life in general. Results highlighted the importance of organizational orientation toward employees, their commitment to work and family roles, and their subjective well-being, as characteristics that might contribute to higher work engagement, success and family satisfaction. Int J Occup Med Environ Health 2018;31(3):281-291. This

Radiation effects and risks: overview and a new risk perception index

International Nuclear Information System (INIS)

Rehani, M.M.

2015-01-01

Uncertainty provides opportunities for differences in perception, and radiation risks at low level of exposures involved in few computed tomography scans fall in this category. While there is good agreement among national and international organisations on risk probability of cancer, risk perception has barely been dealt with by these organisations. Risk perception is commonly defined as the subjective judgment that people make about the characteristics and severity of a risk. Severity and latency are important factors in perception. There is a need to connect all these. Leaving risk perception purely as a subjective judgement provides opportunities for people to amplifying risk. The author postulates a risk perception index as severity divided by latency that becomes determining factor for risk perception. It is hoped that this index will bring rationality in risk perception. (authors)

Sequenced subjective accents for brain-computer interfaces

Science.gov (United States)

Vlek, R. J.; Schaefer, R. S.; Gielen, C. C. A. M.; Farquhar, J. D. R.; Desain, P.

2011-06-01

Subjective accenting is a cognitive process in which identical auditory pulses at an isochronous rate turn into the percept of an accenting pattern. This process can be voluntarily controlled, making it a candidate for communication from human user to machine in a brain-computer interface (BCI) system. In this study we investigated whether subjective accenting is a feasible paradigm for BCI and how its time-structured nature can be exploited for optimal decoding from non-invasive EEG data. Ten subjects perceived and imagined different metric patterns (two-, three- and four-beat) superimposed on a steady metronome. With an offline classification paradigm, we classified imagined accented from non-accented beats on a single trial (0.5 s) level with an average accuracy of 60.4% over all subjects. We show that decoding of imagined accents is also possible with a classifier trained on perception data. Cyclic patterns of accents and non-accents were successfully decoded with a sequence classification algorithm. Classification performances were compared by means of bit rate. Performance in the best scenario translates into an average bit rate of 4.4 bits min-1 over subjects, which makes subjective accenting a promising paradigm for an online auditory BCI.

Measuring of vertical stroke Vub vertical stroke in the forthcoming decade

International Nuclear Information System (INIS)

Kim, C.S.

1997-01-01

I first introduce the importance of measuring V ub precisely. Then, from a theoretician's point of view, I review (a) past history, (b) present trials, and (c) possible future alternatives on measuring vertical stroke V ub vertical stroke and/or vertical stroke V ub /V cb vertical stroke. As of my main topic, I introduce a model-independent method, which predicts Γ(B→X u lν)/Γ(B→X c lν)≡(γ u /γ c ) x vertical stroke V ub /V cb vertical stroke 2 ≅(1.83±0.28) x vertical stroke V ub /V cb vertical stroke 2 and vertical stroke V ub /V cb vertical stroke ≡(γ c /γ u ) 1/2 x [B(B→X u lν)/B(B→ X c lν]) 1/2 ≅(0.74±0.06) x [B(B→X u lν/)B(B→X c lν)] 1/2 , based on the heavy quark effective theory I also explore the possible experimental options to separate B→X u lν from the dominant B→X c lν: the measurement of inclusive hadronic invariant mass distributions, and the 'D-π' (and 'K-π') separation conditions I also clarify the relevant experimental backgrounds. (orig.)

Energy harvesting from coherent resonance of horizontal vibration of beam excited by vertical base motion

Energy Technology Data Exchange (ETDEWEB)

Lan, C. B.; Qin, W. Y. [Department of Engineering Mechanics, Northwestern Polytechnical University, Xi' an 710072 (China)

2014-09-15

This letter investigates the energy harvesting from the horizontal coherent resonance of a vertical cantilever beam subjected to the vertical base excitation. The potential energy of the system has two symmetric potential wells. So, under vertical excitation, the system can jump between two potential wells, which will lead to the large vibration in horizontal direction. Two piezoelectric patches are pasted to harvest the energy. From experiment, it is found that the vertical excitation can make the beam turn to be bistable. The system can transform vertical vibration into horizontal vibration of low frequency when excited by harmonic motion. The horizontal coherence resonance can be observed when excited by a vertical white noise. The corresponding output voltages of piezoelectric films reach high values.

Vertical Relationships on the Workplace and their Influence on Employee's Work Motivation: Sociology Case Study

OpenAIRE

Krösslová, Gabriela

2014-01-01

Subject of this bachelor's thesis is "Vertical relationships at the workplace and theirs influence on employee's work motivation". In the theoretical part, I defined key words, such as: Motivation, vertical and horizontal relationships, work sociology etc. I also stated concepts, related to work sociology and motivation. Practical part deals with the qualitative research (case study), which relates to vertical relationships on workplace as one of the key points of work motivation. That resear...

Variations in rest vertical dimension: effects of standing posture in edentulous patients.

Science.gov (United States)

Makzoume, Joseph E

2007-01-01

The orientation of a patient's head changes, depending on whether he or she is sitting or standing in a relaxed upright position. An edentulous patient's vertical dimension at rest may show variations that can result in an inaccurate determination of his or her occlusal vertical dimension. This study recorded the rest vertical dimension (RVD) established among 60 totally edentulous subjects who were standing in the position of greatest comfort (self-balance position) and compared it with the patients' RVD when they were seated in a relaxed upright position, with the Frankfort Plane parallel to the horizontal. The RVD was measured (in mm) between two dots located on the midline of the face. Two measurements were made: one when the patient was seated upright and relaxed (with the Frankfort Plane parallel to the horizontal) with no head support, and the other when the patient was standing relaxed on both feet in a self-balance position. Five alternated measurements were made for each subject in each position. A mean RVD was calculated for each subject in each body posture and the mean values from both positions were compared. Statistical analysis was performed using Student's t-test (alpha = 0.05). No significant differences were noted between the RVD of the seated and standing positions (P = 0.67).

Psychological methods of subjective risk estimates

International Nuclear Information System (INIS)

Zimolong, B.

1980-01-01

Reactions to situations involving risks can be divided into the following parts/ perception of danger, subjective estimates of the risk and risk taking with respect to action. Several investigations have compared subjective estimates of the risk with an objective measure of that risk. In general there was a mis-match between subjective and objective measures of risk, especially, objective risk involved in routine activities is most commonly underestimated. This implies, for accident prevention, that attempts must be made to induce accurate subjective risk estimates by technical and behavioural measures. (orig.) [de

"Like walking into an empty room": effects of eurythmy therapy on stress perception in comparison with a sports intervention from the subjects' perspective-a qualitative study.

Science.gov (United States)

Berger, B; Bertram, M; Kanitz, J; Pretzer, K; Seifert, G

2015-01-01

Background. Stress and health-related quality of life are important constructs used in treatment evaluation today. This study is based on a randomised controlled trial examining the stress-reducing effect of eurythmy therapy in comparison with step aerobics in 106 healthy but stressed subjects. The aim of the analysis was to characterise changes in the subjective perceptions of the participants. Methods. Interviews were conducted with 76 healthy adults, 36 (f = 31/m = 5) from the eurythmy group and 40 (f = 28/m = 12) from the step aerobics group both analysed by content analysis and phenomenologically. Results. The following categories were identified for the eurythmy therapy group: enabling a productive therapeutic response, emergence of a new perceptual space, reevaluation of the accustomed perception, and emergence of new options for action. Step aerobics places increased physical and intellectual demands. These are perceived differently as pleasant and relaxing, insufficiently challenging and/or boring, and too challenging and thus experienced as stress-enhancing. Conclusion. The qualitative results provided revealing insights into the profound effects of and subjective assignments of meaning to external and internal stress factors. Processes of mental reinterpretation leading to stress reduction can be stimulated by physical procedures such as eurythmy therapy.

Exposure Perception as a Key Indicator of Risk Perception and Acceptance of Sources of Radio Frequency Electromagnetic Fields.

Science.gov (United States)

Freudenstein, Frederik; Wiedemann, Peter M; Brown, Tim W C

2015-01-01

The presented survey was conducted in six European countries as an online study. A total of 2454 subjects participated. Two main research questions were investigated: firstly, how does the cognitive, moral, and affective framing of radio frequency electromagnetic field (RF EMF) exposure perception influence RF EMF risk perception? Secondly, can the deployment of mobile phone base stations have greater acceptance with RF EMF exposure reduction? The findings with respect to the first question clearly indicated that the cognitive framed exposure perception is the main determinant of RF EMF risk perception. The concomitant sensitivity to exposure strength offers an opportunity to improve the acceptance of base stations by exposure reduction. A linear regression analysis supported this assumption: in a fictional test situation, exposure reduction improved the acceptance of base stations, operationalized as the requested distance of the base station from one's own home. Furthermore, subjects with high RF EMF risk perception were most sensitive to exposure reduction. On average, a 70% exposure reduction reduced the requested distance from about 2000 meters to 1000 meters. The consequences for risk communication are discussed.

Exposure Perception as a Key Indicator of Risk Perception and Acceptance of Sources of Radio Frequency Electromagnetic Fields

Science.gov (United States)

Wiedemann, Peter M.; Brown, Tim W. C.

2015-01-01

The presented survey was conducted in six European countries as an online study. A total of 2454 subjects participated. Two main research questions were investigated: firstly, how does the cognitive, moral, and affective framing of radio frequency electromagnetic field (RF EMF) exposure perception influence RF EMF risk perception? Secondly, can the deployment of mobile phone base stations have greater acceptance with RF EMF exposure reduction? The findings with respect to the first question clearly indicated that the cognitive framed exposure perception is the main determinant of RF EMF risk perception. The concomitant sensitivity to exposure strength offers an opportunity to improve the acceptance of base stations by exposure reduction. A linear regression analysis supported this assumption: in a fictional test situation, exposure reduction improved the acceptance of base stations, operationalized as the requested distance of the base station from one's own home. Furthermore, subjects with high RF EMF risk perception were most sensitive to exposure reduction. On average, a 70% exposure reduction reduced the requested distance from about 2000 meters to 1000 meters. The consequences for risk communication are discussed. PMID:26229540

Visual Perception Based Rate Control Algorithm for HEVC

Science.gov (United States)

Feng, Zeqi; Liu, PengYu; Jia, Kebin

2018-01-01

For HEVC, rate control is an indispensably important video coding technology to alleviate the contradiction between video quality and the limited encoding resources during video communication. However, the rate control benchmark algorithm of HEVC ignores subjective visual perception. For key focus regions, bit allocation of LCU is not ideal and subjective quality is unsatisfied. In this paper, a visual perception based rate control algorithm for HEVC is proposed. First bit allocation weight of LCU level is optimized based on the visual perception of luminance and motion to ameliorate video subjective quality. Then λ and QP are adjusted in combination with the bit allocation weight to improve rate distortion performance. Experimental results show that the proposed algorithm reduces average 0.5% BD-BR and maximum 1.09% BD-BR at no cost in bitrate accuracy compared with HEVC (HM15.0). The proposed algorithm devotes to improving video subjective quality under various video applications.

Axiology, the Subject and the Chair

Science.gov (United States)

Melville, Wayne; Campbell, Todd; Jones, Doug

2017-08-01

This article addresses two gaps in the literature related to science department chairs: the axiological relationship between the chair and science, the subject, and the perceptions of the chair with respect to teaching and learning within their departments. In this work, axiology is used to understand how the chair's values toward the subject influenced his own perceived capacity to lead learning within his department in a reformed discourse. A narrative inquiry methodology was used to consider the chair's experiences in the development of his identify over his life span in the form of two stories: (1) the relationship between the chair and science, the subject, and (2) the perceptions of the chair with regards to teacher learning within the department. The findings revealed that the work and career of the chair in this study were authored by strong elements of personal continuity and points of stability around the valuing of science, the subject, even as this valuing evolved from being more focused on epistemic values early in his career, to being more concerned with universal values connected to his legacy and his department later in his career.

The power of pictures: Vertical picture angles in power pictures

NARCIS (Netherlands)

S.R. Giessner (Steffen); M.K. Ryan (Michelle); T.W. Schubert (Thomas); N. van Quaquebeke (Niels)

2011-01-01

textabstractAbstract: Conventional wisdom suggests that variations in vertical picture angle cause the subject to appear more powerful when depicted from below and less powerful when depicted from above. However, do the media actually use such associations to represent individual differences in

Absolute and convective instabilities of a film flow down a vertical fiber subjected to a radial electric field

Science.gov (United States)

Liu, Rong; Chen, Xue; Ding, Zijing

2018-01-01

We consider the motion of a gravity-driven flow down a vertical fiber subjected to a radial electric field. This flow exhibits rich dynamics including the formation of droplets, or beads, driven by a Rayleigh-Plateau mechanism modified by the presence of gravity as well as the Maxwell stress at the interface. A spatiotemporal stability analysis is performed to investigate the effect of electric field on the absolute-convective instability (AI-CI) characteristics. We performed a numerical simulation on the nonlinear evolution of the film to examine the transition from CI to AI regime. The numerical results are in excellent agreement with the spatiotemporal stability analysis. The blowup behavior of nonlinear simulation predicts the formation of touchdown singularity of the interface due to the effect of electric field. We try to connect the blowup behavior with the AI-CI characteristics. It is found that the singularities mainly occur in the AI regime. The results indicate that the film may have a tendency to form very sharp tips due to the enhancement of the absolute instability induced by the electric field. We perform a theoretical analysis to study the behaviors of the singularities. The results show that there exists a self-similarity between the temporal and spatial distances from the singularities.

THE ACUTE EFFECTS OF BACK SQUATS ON VERTICAL JUMP PERFORMANCE IN MEN AND WOMEN

Directory of Open Access Journals (Sweden)

Gavin L. Moir

2010-06-01

Full Text Available The aim of the present study was to investigate the acute effects of performing back squats on subsequent performance during a series of vertical jumps in men and women. Twelve men and 12 women were tested on three separate occasions, the first of which was used to determine their 1-repetition maximum (1-RM parallel back squat. Following this, subjects performed a potentiation and a control treatment in a counterbalanced order. The potentiation treatment culminated with subjects performing parallel back squats with a load equivalent to 70% 1- RM for three repetitions, following which they performed one countermovement vertical jump (CMJ for maximal height every three minutes for a total of 10 jumps. During the control treatment, subjects performed only the CMJs. Jump height (JH and vertical stiffness (VStiff were calculated for each jump from the vertical force signal recorded from a force platform. There were no significant changes in JH or VStiff following the treatments and no significant differences in the responses between men and women (p > 0.05. Correlations between normalized 1-RM back squat load and the absolute change in JH and VStiff were small to moderate for both men and women, with most correlations being negative. Large variations in response to the back squats were noted in both men and women. The use of resistance exercises performed prior to a series of vertical jumps can result in improvements in performance in certain individuals, although the gains tend to be small and dependent upon the mechanical variable measured. There does not seem to be any differences between men and women in the response to dynamic potentiation protocols

Subjective perception of radioactivity. No change post successful treatment with radioiodine; Strahlen bleiben boese. Keine Aenderung der subjektiven Konzepte von Radioaktivitaet nach erfolgreicher Radioiodtherapie

Energy Technology Data Exchange (ETDEWEB)

Freudenberg, L.S.; Mueller, S.P.; Beyer, T.; Bockisch, A. [Universitaetsklinikum Essen (Germany). Klinik fuer Nuklearmedizin

2009-07-01

We assess the attitude of patients with thyroid disease towards radiation and radioactivity before and after radioiodine therapy by means of a cultural-anthropological approach. We evaluate in patient interviews how their subjective attitude towards radioactivity as an abstract term and towards radioactivity in the medical context on the basis of their personal experiences with radionuclide therapy. 29 patients with autonomously functioning thyroid lesions (17 women, 12 men, 35-79 years) were included in this study. All patients were interviewed prior to and 22-27 month post radioiodine therapy in an open dialogue with the principal investigator. Patients were asked to describe their attitude towards radioactivity in general and towards radioiodine therapy in particular. Patients were asked to use a scoring system (1: positive, 5: negative) to quantify their perception of radioactivity. The personal perception of radioactivity as an abstract term does not change significantly (p = 0.15) before and after radioiodine therapy. This perception is linked to mostly negative impressions of radiactivity. However, patients become more positive when assessing the value of radioactivity as part of their therapy regimen. Thus, we observe a significant increase in percepted value of radioactivity post radioiodine therapy (p = 0.03). Patients continue to view radioactivity as something negative despite treatment success following radioiodine therapy. Our results provide useful information for patient information by the nuclear medicine physician prior to a radioiodine therapy. (orig.)

The Power of Pictures : Vertical Picture Angles in Power Pictures

NARCIS (Netherlands)

Giessner, Steffen R.; Ryan, Michelle K.; Schubert, Thomas W.; van Quaquebeke, Niels

2011-01-01

Conventional wisdom suggests that variations in vertical picture angle cause the subject to appear more powerful when depicted from below and less powerful when depicted from above. However, do the media actually use such associations to represent individual differences in power? We argue that the

Measurement of vertical stroke Vub vertical stroke using b hadron semileptonic decay

International Nuclear Information System (INIS)

Abbiendi, G.; Aakesson, P.F.

2001-01-01

The magnitude of the CKM matrix element vertical stroke V ub vertical stroke is determined by measuring the inclusive charmless semileptonic branching fraction of beauty hadrons at OPAL based on b → X u lν event topology and kinematics. This analysis uses OPAL data collected between 1991 and 1995, which correspond to about four million hadronic Z decays. We measure Br(b → X u lν) to be (1.63 ±0.53 +0.55 -0.62 ) x 10 -3 . The first uncertainty is the statistical error and the second is the systematic error. From this analysis, vertical stroke V ub vertical stroke is determined to be: vertical stroke V ub vertical stroke =(4.00±0.65(stat) +0.67 -0.76 (sys)±0.19(HQE)) x 10 -3 . The last error represents the theoretical uncertainties related to the extraction of vertical stroke V ub vertical stroke from Br(b→X u l ν) using the Heavy Quark Expansion. (orig.)

Consumers' sensory and nutritional perceptions of three types of milk

NARCIS (Netherlands)

Bus, A.E.M.; Worsley, A.

2003-01-01

Objective: To identify consumer perceptions of whole milk, reduced-fat milk and soy milk, and to investigate demographic influences on perceptions and types of milk consumption. Design and setting: Questionnaires covering nutritional and sensory perceptions of three types of milk. Subjects: Three

Exposure Perception as a Key Indicator of Risk Perception and Acceptance of Sources of Radio Frequency Electromagnetic Fields

Directory of Open Access Journals (Sweden)

Frederik Freudenstein

2015-01-01

Full Text Available The presented survey was conducted in six European countries as an online study. A total of 2454 subjects participated. Two main research questions were investigated: firstly, how does the cognitive, moral, and affective framing of radio frequency electromagnetic field (RF EMF exposure perception influence RF EMF risk perception? Secondly, can the deployment of mobile phone base stations have greater acceptance with RF EMF exposure reduction? The findings with respect to the first question clearly indicated that the cognitive framed exposure perception is the main determinant of RF EMF risk perception. The concomitant sensitivity to exposure strength offers an opportunity to improve the acceptance of base stations by exposure reduction. A linear regression analysis supported this assumption: in a fictional test situation, exposure reduction improved the acceptance of base stations, operationalized as the requested distance of the base station from one’s own home. Furthermore, subjects with high RF EMF risk perception were most sensitive to exposure reduction. On average, a 70% exposure reduction reduced the requested distance from about 2000 meters to 1000 meters. The consequences for risk communication are discussed.

A comprehensive model of audiovisual perception: both percept and temporal dynamics.

Directory of Open Access Journals (Sweden)

Patricia Besson

Full Text Available The sparse information captured by the sensory systems is used by the brain to apprehend the environment, for example, to spatially locate the source of audiovisual stimuli. This is an ill-posed inverse problem whose inherent uncertainty can be solved by jointly processing the information, as well as introducing constraints during this process, on the way this multisensory information is handled. This process and its result--the percept--depend on the contextual conditions perception takes place in. To date, perception has been investigated and modeled on the basis of either one of two of its dimensions: the percept or the temporal dynamics of the process. Here, we extend our previously proposed audiovisual perception model to predict both these dimensions to capture the phenomenon as a whole. Starting from a behavioral analysis, we use a data-driven approach to elicit a bayesian network which infers the different percepts and dynamics of the process. Context-specific independence analyses enable us to use the model's structure to directly explore how different contexts affect the way subjects handle the same available information. Hence, we establish that, while the percepts yielded by a unisensory stimulus or by the non-fusion of multisensory stimuli may be similar, they result from different processes, as shown by their differing temporal dynamics. Moreover, our model predicts the impact of bottom-up (stimulus driven factors as well as of top-down factors (induced by instruction manipulation on both the perception process and the percept itself.

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…

Early visual responses predict conscious face perception within and between subjects during binocular rivalry

DEFF Research Database (Denmark)

Sandberg, Kristian; Bahrami, Bahador; Kanai, Ryota

2013-01-01

Previous studies indicate that conscious face perception may be related to neural activity in a large time window around 170–800 msec after stimulus presentation, yet in the majority of these studies changes in conscious experience are confounded with changes in physical stimulation. Using...... multivariate classification on MEG data recorded when participants reported changes in conscious perception evoked by binocular rivalry between a face and a grating, we showed that only MEG signals in the 120–320 msec time range, peaking at the M170 around 180 msec and the P2m at around 260 msec, reliably...... activity associated with conscious face perception generalized from one participant to another around the times of maximum prediction accuracy. Our work thus demonstrates that the neural correlates of particular conscious contents (here, faces) are highly consistent in time and space within individuals...

Feelings and intervention judgments as mediators in the risk perception-intention relationship.

Science.gov (United States)

Soureti, Anastasia; Hurling, Robert; Cobain, Mark R; van Mechelen, Willem; Chinapaw, Mai

2013-07-01

To explore the mediating role of measures of persuasion in the relationship between risk perceptions and intentions. The first study included 413 obese subjects (mean age = 45.3 years); the second study, 781 overweight subjects (mean age = 46.6 years). All measures were assessed by self-report. Feelings and intervention judgments were mediators in the relationship between risk perceptions and intention to eat healthier, do more physical activity (study 1) and intention to reduce saturated fat (study 2). Feelings was the only mediator in the relationship between risk perceptions and intention to stop smoking (study 1). Future interventions targeting risk perceptions to increase intentions are likely to be more effective if subjects find the information emotionally impactful, credible, and engaging.

RF EMF Risk Perception Revisited: Is the Focus on Concern Sufficient for Risk Perception Studies?

Science.gov (United States)

Wiedemann, Peter M; Freudenstein, Frederik; Böhmert, Christoph; Wiart, Joe; Croft, Rodney J

2017-06-08

An implicit assumption of risk perception studies is that concerns expressed in questionnaires reflect concerns in everyday life. The aim of the present study is to check this assumption, i.e., the extrapolability of risk perceptions expressed in a survey, to risk perceptions in everyday life. To that end, risk perceptions were measured by a multidimensional approach. In addition to the traditional focus on measuring the magnitude of risk perceptions, the thematic relevance (how often people think about a risk issue) and the discursive relevance (how often people think about or discuss a risk issue) of risk perceptions were also collected. Taking into account this extended view of risk perception, an online survey was conducted in six European countries with 2454 respondents, referring to radio frequency electromagnetic field (RF EMF) risk potentials from base stations, and access points, such as WiFi routers and cell phones. The findings reveal that the present study's multidimensional approach to measuring risk perception provides a more differentiated understanding of RF EMF risk perception. High levels of concerns expressed in questionnaires do not automatically imply that these concerns are thematically relevant in everyday life. We use thematic relevance to distinguish between enduringly concerned (high concern according to both questionnaire and thematic relevance) and not enduringly concerned participants (high concern according to questionnaire but no thematic relevance). Furthermore, we provide data for the empirical value of this distinction: Compared to other participants, enduringly concerned subjects consider radio frequency electromagnetic field exposure to a greater extent as a moral and affective issue. They also see themselves as highly exposed to radio frequency electromagnetic fields. However, despite these differences, subjects with high levels of thematic relevance are nevertheless sensitive to exposure reduction as a means for improving the

RF EMF Risk Perception Revisited: Is the Focus on Concern Sufficient for Risk Perception Studies?

Science.gov (United States)

Wiedemann, Peter M.; Freudenstein, Frederik; Böhmert, Christoph; Wiart, Joe; Croft, Rodney J.

2017-01-01

An implicit assumption of risk perception studies is that concerns expressed in questionnaires reflect concerns in everyday life. The aim of the present study is to check this assumption, i.e., the extrapolability of risk perceptions expressed in a survey, to risk perceptions in everyday life. To that end, risk perceptions were measured by a multidimensional approach. In addition to the traditional focus on measuring the magnitude of risk perceptions, the thematic relevance (how often people think about a risk issue) and the discursive relevance (how often people think about or discuss a risk issue) of risk perceptions were also collected. Taking into account this extended view of risk perception, an online survey was conducted in six European countries with 2454 respondents, referring to radio frequency electromagnetic field (RF EMF) risk potentials from base stations, and access points, such as WiFi routers and cell phones. The findings reveal that the present study’s multidimensional approach to measuring risk perception provides a more differentiated understanding of RF EMF risk perception. High levels of concerns expressed in questionnaires do not automatically imply that these concerns are thematically relevant in everyday life. We use thematic relevance to distinguish between enduringly concerned (high concern according to both questionnaire and thematic relevance) and not enduringly concerned participants (high concern according to questionnaire but no thematic relevance). Furthermore, we provide data for the empirical value of this distinction: Compared to other participants, enduringly concerned subjects consider radio frequency electromagnetic field exposure to a greater extent as a moral and affective issue. They also see themselves as highly exposed to radio frequency electromagnetic fields. However, despite these differences, subjects with high levels of thematic relevance are nevertheless sensitive to exposure reduction as a means for improving the

Public perceptions of energy system risks: some policy implications

International Nuclear Information System (INIS)

Thomas, K.; Otway, H.J.

1980-01-01

The subject is discussed under the headings: introduction; perceptions, beliefs and attitudes; the survey of public perceptions and attitudes towards energy systems; attitudes towards the five energy systems (nuclear, coal, oil, solar and hydro); perceptions of energy systems - the underlying dimensions of belief (economic benefits; environmental risk; psychological and physical risk; indirect risk; technology development); differential analysis of the perceptions of those pro and con nuclear energy; summary of perceptions of energy systems - relevance to the Austrian dilemma; policy implications. (U.K.)

Measurement of the CKM matrix element vertical stroke Vts vertical stroke 2

International Nuclear Information System (INIS)

Unverdorben, Christopher Gerhard

2015-03-01

This is the first direct measurement of the CKM matrix element vertical stroke V ts vertical stroke, using data collected by the ATLAS detector in 2012 at √(s)= 8 TeV pp-collisions with a total integrated luminosity of 20.3 fb -1 . The analysis is based on 112 171 reconstructed t anti t candidate events in the lepton+jets channel, having a purity of 90.0 %. 183 t anti t→W + W - b anti s decays are expected (charge conjugation implied), which are available for the extraction of the CKM matrix element vertical stroke V ts vertical stroke 2 . To identify these rare decays, several observables are examined, such as the properties of jets, tracks and of b-quark identification algorithms. Furthermore, the s-quark hadrons K 0 s are considered, reconstructed by a kinematic fit. The best observables are combined in a multivariate analysis, called ''boosted decision trees''. The responses from Monte Carlo simulations are used as templates for a fit to data events yielding a significance value of 0.7σ for t→s+W decays. An upper limit of vertical stroke V ts vertical stroke 2 <1.74 % at 95 % confidence level is set, including all systematic and statistical uncertainties. So this analysis, using a direct measurement of the CKM matrix element vertical stroke V ts vertical stroke 2 , provides the best direct limit on vertical stroke V ts vertical stroke 2 up to now.

Subjective versus objective risk in genetic counseling for hereditary breast and/or ovarian cancers

Directory of Open Access Journals (Sweden)

Sperduti Isabella

2009-12-01

Full Text Available Abstract Background Despite the fact that genetic counseling in oncology provides information regarding objective risks, it can be found a contrast between the subjective and objective risk. The aims of this study were to evaluate the accuracy of the perceived risk compared to the objective risk estimated by the BRCApro computer model and to evaluate any associations between medical, demographic and psychological variables and the accuracy of risk perception. Methods 130 subjects were given medical-demographic file, Cancer and Genetic Risk Perception, Hospital Anxiety-Depression Scale. It was also computed an objective evaluation of the risk by the BRCApro model. Results The subjective risk was significantly higher than objective risk. The risk of tumour was overestimated by 56%, and the genetic risk by 67%. The subjects with less cancer affected relatives significantly overestimated their risk of being mutation carriers and made a more innacurate estimation than high risk subjects. Conclusion The description of this sample shows: general overestimation of the risk, inaccurate perception compared to BRCApro calculation and a more accurate estimation in those subjects with more cancer affected relatives (high risk subjects. No correlation was found between the levels of perception of risk and anxiety and depression. Based on our findings, it is worth pursuing improved communication strategies about the actual cancer and genetic risk, especially for subjects at "intermediate and slightly increased risk" of developing an hereditary breast and/or ovarian cancer or of being mutation carrier.

Sensory adaptation for timing perception.

Science.gov (United States)

Roseboom, Warrick; Linares, Daniel; Nishida, Shin'ya

2015-04-22

Recent sensory experience modifies subjective timing perception. For example, when visual events repeatedly lead auditory events, such as when the sound and video tracks of a movie are out of sync, subsequent vision-leads-audio presentations are reported as more simultaneous. This phenomenon could provide insights into the fundamental problem of how timing is represented in the brain, but the underlying mechanisms are poorly understood. Here, we show that the effect of recent experience on timing perception is not just subjective; recent sensory experience also modifies relative timing discrimination. This result indicates that recent sensory history alters the encoding of relative timing in sensory areas, excluding explanations of the subjective phenomenon based only on decision-level changes. The pattern of changes in timing discrimination suggests the existence of two sensory components, similar to those previously reported for visual spatial attributes: a lateral shift in the nonlinear transducer that maps relative timing into perceptual relative timing and an increase in transducer slope around the exposed timing. The existence of these components would suggest that previous explanations of how recent experience may change the sensory encoding of timing, such as changes in sensory latencies or simple implementations of neural population codes, cannot account for the effect of sensory adaptation on timing perception.

Subject Teachers as Educators for Sustainability: A Survey Study

Directory of Open Access Journals (Sweden)

Anna Uitto

2017-01-01

Full Text Available Sustainability education (SE is included in school curricula to integrate the principles, values, and practices of sustainable development (SD into all education. This study investigates lower secondary school subject teachers as educators for sustainability. A survey was used to study the perceptions of 442 subject teachers from 49 schools in Finland. There were significant differences between the subject teachers’ perceptions of their SE competence, and the frequency with which they used different dimensions of SE (ecological, economic, social, well-being, cultural in their teaching varied. Teachers’ age had a small effect, but gender, school, and its residential location were nonsignificant factors. Teachers could be roughly classified into three different subgroups according to their perceptions of the role of SE in their teaching; those who considered three SE dimensions rather often and used holistic sustainability approaches in their teaching (biology, geography, history; those who considered two or three dimensions often but were not active in holistic teaching (mother tongue, religion, visual arts, crafts, music, physical and health education, and home economics and those who used one SE dimension or consider only one holistic approach in their teaching (mathematics, physics, chemistry and language. Subject teachers’ awareness of their SE competence is important to encourage them to plan and implement discipline-based and interdisciplinary SE in their teaching. The specific SE expertise of subject teachers should be taken into account in teacher training and education.

The reliability and clinical correlates of figure-ground perception in schizophrenia.

Science.gov (United States)

Malaspina, Dolores; Simon, Naomi; Goetz, Raymond R; Corcoran, Cheryl; Coleman, Eliza; Printz, David; Mujica-Parodi, Lilianne; Wolitzky, Rachel

2004-01-01

Schizophrenia subjects are impaired in a number of visual attention paradigms. However, their performance on tests of figure-ground visual perception (FGP), which requires subjects to visually discriminate figures embedded in a rival background, is relatively unstudied. We examined FGP in 63 schizophrenia patients and 27 control subjects and found that the patients performed the FGP test reliably and had significantly lower FGP scores than the control subjects. Figure-ground visual perception was significantly correlated with other neuropsychological test scores and was inversely related to negative symptoms. It was unrelated to antipsychotic medication treatment. Figure-ground visual perception depends on "top down" processing of visual stimuli, and thus this data suggests that dysfunction in the higher-level pathways that modulate visual perceptual processes may also be related to a core defect in schizophrenia.

Relationship between self- perception of malodour and actual estimation of malodour in a group of dental patients.

Science.gov (United States)

Ehizele, A O; Ojehanon, P I

2013-12-01

The aim of this study was to determine the relationship between the concentration of volatile sulphur compounds in mouth air of young adult and their self perception of malodour and also to determine the relationship between the organoleptic assessment of young adult and their perception of malodour. A total of 400 willing participants were studied and they were grouped into two based on the health of their periodontium. Subjects were asked for self perception of malodour and organoleptic assessment was done to assess the level of malodour using the Rosenberg 0-5 scoring system. The concentration of volatile sulphur compounds (VSC) was determined objectively using the Halimeter. Eighty subjects reported self perception of malodour i.e. 39 males (48.7%) and 41 females (51.3%). Only 9% of the subjects without periodontal diseases reported self perception of oral malodour while 31% of subjects with periodontal disease had similar claims. Majority (86%) of those who had VSC concentration less than 181 ppb claimed to have no self perception of malodour while 41% of those who had VSC concentration greater than 250 ppb had self perception of malodour. More than half (53.8%) of subjects with VSC concentration greater than 250 ppb had organoleptic score of 3. Half of subjects with organoleptic assessment score of 3 had self perception of malodour. It can be concluded from this study that a relationship exists between self-perception of oral malodour, organoleptic assessment and the concentration of volatile sulphur compounds in mouth air of subjects.

Longitudinal growth changes in subjects with deepbite.

Science.gov (United States)

Baccetti, Tiziano; Franchi, Lorenzo; McNamara, James A

2011-08-01

This study was a cephalometric evaluation of the growth changes in untreated subjects with deepbite at 4 time points during their developmental ages (from the early mixed dentition to the permanent dentition, and from the prepubertal phase to young adulthood). A sample of 29 subjects with deepbite (overbite >4.5 mm) was followed longitudinally from about 9 through about 18 years of age. Dentofacial changes at 4 times, defined by the cervical vertebral maturation method, were analyzed on lateral cephalograms. Nonparametric statistical analysis was used for comparisons. Overbite improved on average by 1.3 mm between the first and last measurements; it worsened significantly during the prepubertal period, but it improved significantly at the pubertal growth spurt. From the prepubertal ages through young adulthood, overbite improved in 83% of the subjects and self-corrected in 62% of the subjects. Improvements in overbite were related to the initial amount of maxillary incisor proclination. The significant improvement in overbite during the adolescent growth spurt depended on the amount of vertical growth of the mandibular ramus and the eruption of the mandibular molars. Subjects with deepbite showed worsened occlusal conditions during the prepubertal and mixed dentition phases, but had significant improvements thereafter. Improvements in overbite cannot be predicted on the basis of skeletal vertical relationships. These results provide useful indications for appropriate orthodontic treatment timing for an increased overbite. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Student Perceptions of High-Achieving Classmates

Science.gov (United States)

Händel, Marion; Vialle, Wilma; Ziegler, Albert

2013-01-01

The reported study investigated students' perceptions of their high-performing classmates in terms of intelligence, social skills, and conscientiousness in different school subjects. The school subjects for study were examined with regard to cognitive, physical, and gender-specific issues. The results show that high academic achievements in…

Masticatory mechanosensitivity, mouth opening and impact of headache in subjects with a history of orthodontics use: a cross-sectional study.

Science.gov (United States)

Heredia-Rizo, A M; Rodríguez-Blanco, C; Oliva-Pascual-Vaca, Á; Torres-Lagares, D; Albornoz-Cabello, M; Piña-Pozo, F; Luque-Carrasco, A

2014-08-01

The correlation between orthodontics and the development of signs and symptoms of temporomandibular disorders (TMD) is a major concern in the physical rehabilitation field. The aim of the study was to observe whether subjects with a history of orthodontics use show differences from subjects who have never used orthodontics in: 1) masseter and temporalis muscle mechanosensitivity; 2) maximal vertical mouth opening (VMO); and 3) the impact of headache on their quality of life. Cross-sectional study. The study was carried out in the Faculty of Nursing, Physiotherapy and Podiatry of the University of Sevilla, Spain. All participants were pre graduate students from the University of Sevilla, Spain. The final sample comprised 65 subjects (N.=65) with a mean age of 21 ± 2.46 years (18-29) divided into two groups; orthodontics group (N.=31) and non-orthodontics group (N.=34). All students followed the same testing protocol. Measurements were taken of the pressure pain threshold (PPT) in two locations of the masseter (M1, M2) and temporalis (T1, T2) muscles, the maximal VMO, and the incidence of headache (Headache Impact Test-6; HIT-6, Spanish version). The measured values of the masticatory muscle PPTs were lower in the non-orthodontics group. Besides, the maximal VMO and HIT-6 scores were better in the orthodontics group. Nevertheless, none of these intergroup differences were statistically significant (ANOVA test): (M1 P=0.790); (M2 P=0.329); (T1 P=0.249); (T2 P=0.440); (HIT-6 P=0.443); (VMO P=0.626). A previous history of orthodontics use does not seem to lead to any greater sensitivity of the masticatory muscles, limitations of vertical mouth opening, or greater impact of headache on the subject's quality of life. There is no evidence enough to support either a positive or negative correlation between orthodontics and signs and symptoms of TMD. Pain is a subjective perception and it is influenced by several factors. It remains uncertain if the use of orthodontics

Dynamics of force and muscle stimulation in human vertical jumping

NARCIS (Netherlands)

Bobbert, M.F.; van Zandwijk, J.P.

1999-01-01

PURPOSE: The purpose of this study was to gain insight into the importance of stimulation dynamics for force development in human vertical jumping. METHODS: Maximum height squat jumps were performed by 21 male subjects. As a measure of signal dynamics, rise time (RT) was used, i.e., the time taken

Colour Perception on Facial Expression towards Emotion

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Rubita Sudirman

2012-12-01

Full Text Available This study is to investigate human perceptions on pairing of facial expressions of emotion with colours. A group of 27 subjects consisting mainly of younger and Malaysian had participated in this study. For each of the seven faces, which expresses the basic emotions neutral, happiness, surprise, anger, disgust, fear and sadness, a single colour is chosen from the eight basic colours for the match of best visual look to the face accordingly. The different emotions appear well characterized by a single colour. The approaches used in this experiment for analysis are psychology disciplines and colours engineering. These seven emotions are being matched by the subjects with their perceptions and feeling. Then, 12 male and 12 female data are randomly chosen from among the previous data to make a colour perception comparison between genders. The successes or failures in running of this test depend on the possibility of subjects to propose their every single colour for each expression. The result will translate into number and percentage as a guide for colours designers and psychology field.

Effectiveness of Different Rest Intervals Following Whole-Body Vibration on Vertical Jump Performance between College Athletes and Recreationally Trained Females

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Nicole C. Dabbs

2015-09-01

Full Text Available The purpose of this study was to evaluate the effect of different rest intervals following whole-body vibration on counter-movement vertical jump performance. Sixteen females, eight recreationally trained and eight varsity athletes volunteered to participate in four testing visits separated by 24 h. Visit one acted as a familiarization visit where subjects were introduced to the counter-movement vertical jump and whole-body vibration protocols. Visits 2–4 contained 2 randomized conditions. Whole-body vibration was administered in four bouts of 30 s with 30 s rest between bouts. During whole-body vibration subjects performed a quarter squat every 5 s, simulating a counter-movement vertical jump. Whole-body vibration was followed by three counter-movement vertical jumps with five different rest intervals between the vibration exposure and jumping. For a control condition, subjects performed squats with no whole-body vibration. There was a significant (p < 0.05 main effect for time for vertical jump height, peak power output, and relative ground reaction forces, where a majority of individuals max jump from all whole-body vibration conditions was greater than the control condition. There were significant (p < 0.05 group differences, showing that varsity athletes had a greater vertical jump height and peak power output compared to recreationally trained females. There were no significant (p > 0.05 group differences for relative ground reaction forces. Practitioners and/or strength and conditioning coaches may utilize whole-body vibration to enhance acute counter-movement vertical jump performance after identifying individuals optimal rest time in order to maximize the potentiating effects.

Acute effects of unilateral whole body vibration training on single leg vertical jump height and symmetry in healthy men.

Science.gov (United States)

Shin, Seungho; Lee, Kyeongjin; Song, Changho

2015-12-01

[Purpose] The aim of the present study was to investigate the acute effects of unilateral whole body vibration training on height and symmetry of the single leg vertical jump in healthy men. [Subjects] Thirty males with no history of lower limb dysfunction participated in this study. [Methods] The participants were randomly allocated to one of three groups: the unilateral vibratory stimulation group (n=10), bilateral vibratory stimulation group (n=10), and, no vibratory stimulation group (n=10). The subjects in the unilateral and bilateral stimulation groups participated in one session of whole body vibration training at 26 Hz for 3 min. The no vibratory stimulation group subjects underwent the same training for 3 min without whole body vibration. All participants performed the single leg vertical jump for each lower limb, to account for the strong and weak sides. The single leg vertical jump height and symmetry were measured before and after the intervention. [Results] The single leg vertical jump height of the weak lower limb significantly improved in the unilateral vibratory stimulation group, but not in the other groups. The single leg vertical jump height of the strong lower limb significantly improved in the bilateral vibratory stimulation group, but not in the other groups. The single leg vertical jump symmetry significantly improved in the unilateral vibratory stimulation group, but not in the other groups. [Conclusion] Therefore, the present study found that the effects of whole body vibration training were different depending on the type of application. To improve the single leg vertical jump height in the weak lower limbs as well as limb symmetry, unilateral vibratory stimulation might be more desirable.

Customized rating assessment of climate suitability (CRACS): climate satisfaction evaluation based on subjective perception

Science.gov (United States)

Lin, Tzu-Ping; Yang, Shing-Ru; Matzarakis, Andreas

2015-12-01

Climate not only influences the behavior of people in urban environments but also affects people's schedules and travel plans. Therefore, providing people with appropriate long-term climate evaluation information is crucial. Therefore, we developed an innovative climate assessment system based on field investigations conducted in three cities located in Northern, Central, and Southern Taiwan. The field investigations included the questionnaire surveys and climate data collection. We first analyzed the relationship between the participants and climate parameters comprising physiologically equivalent temperature, air temperature, humidity, wind speed, solar radiation, cloud cover, and precipitation. Second, we established the neutral value, comfort range, and dissatisfied range of each parameter. Third, after verifying that the subjects' perception toward the climate parameters vary based on individual preferences, we developed the customized rating assessment of climate suitability (CRACS) approach, which featured functions such as personalized and default climate suitability information to be used by users exhibiting varying demands. Finally, we performed calculations using the climate conditions of two cities during the past 10 years to demonstrate the performance of the CRACS approach. The results can be used as a reference when planning activities in the city or when organizing future travel plans. The flexibility of the assessment system enables it to be adjusted for varying regions and usage characteristics.

Kantowska metafizyka percepcji (Kant’s Metaphysics of Perception

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Paweł Sikora

2009-06-01

Full Text Available This article treats of an issue of Kant’s the metaphysics of perception as a specific sphere where concept of sense perception within transcendental philosophy seem to be rooted into a wider context of metaphysical presuppositions. The text is an epitome of a few Kant’s aporias which appear when he does not notice a metaphysical background which constitutes basic relation between subject and object in sense perception.

A Cross-Cultural Study of Role Perceptions.

Science.gov (United States)

Triandis, Harry C.; And Others

Survey responses from 1,620 subjects in the United States, Greece, India, Peru, and Taiwan provide information on cross-cultural role perceptions. Study data reveal (1) the principal factors accounting for the variance in role perception in each culture, (2) those factors that are the same in all cultures, (3) the equivalent factor scores that…

Alteration in salivary properties and taste perception in OSMF

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Sujatha Dyasanoor

2016-01-01

Full Text Available Objective: To assess and compare the salivary flow rate (SFR, pH and taste perception among oral submucous fibrosis (OSMF and apparently healthy subjects. Materials and Methods: Ninety subjects (45 OSMF + 45 controls were enrolled in the study for estimating and analogizing the SFR, pH, and taste perception executing modified Schirmer, pH, and taste strips. The SFR, pH, and taste perception were evaluated and compared between 14 Stage I and 31 Stage II OSMF subjects. The entered data were analyzed using SPSS 21.0 software. Results: A statistically significant decrease in SFR among OSMF group (23.4 mm at 3rd min and hypogeusia to salty (62.2%, and dysgeusia to sour taste (40% when compared to apparently healthy subjects (30.7 mm at 3rd min was noted. Statistical significance (P < 0.05% inferring hyposalivation in Stage II OSMF (24.1 mm at 3rd min juxtaposing with Stage I OSMF (31.4 mm at 3rd min. Statistically significant hypogeusia to salty (n = 23 and sweet (n = 16 and dysgeusia (n = 14 to sour among Stage II OSMF when differentiated with Stage I OSMF. The mean pH among the OSMF and control groups demonstrated no statistical significance. Conclusion: The findings from the study demonstrated marked decrease of SFR and taste perception to salty and sour among Stage II OSMF when compared to Stage I OSMF subjects.

Children's perception of physical symptoms: The example of asthma.

NARCIS (Netherlands)

Rietveld, S.; Prins, P.J.M.; Lahey, B.B.; Kazdin, A.E.

1998-01-01

Introduces symptom perception as a concept to explain and understand the discordance between objective and subjective symptoms of disease. Contemporary models describing symptom perception and factors that influence these symptom perceptual processes are evaluated in light of recent empirical

Proposta de medição da posição vertical da laringe em repouso Proposal of measurement of vertical larynx position at rest

Directory of Open Access Journals (Sweden)

Osiris de Oliveira Camponês do Brasil

2005-06-01

Full Text Available OBJETIVO: Esta pesquisa tem como objetivo propor uma forma de medir a posição vertical da laringe (PVL no pescoço, em repouso, de adultos jovens sem queixas vocais. FORMA DE ESTUDO: Estudo de coorte transversal. MATERIAL E MÉTODO: Participaram da pesquisa 68 sujeitos, faixa etária de 18 a 44 anos de idade, sendo 33 do sexo feminino e 35 do sexo masculino. Os pontos de referência utilizados para a pesquisa foram os ângulos da mandíbula direito e esquerdo (AMD e AME, o centro do arco da cartilagem cricóidea (CC e o centro da fúrcula esternal (FE. Para a obtenção das medidas, os sujeitos foram orientados a permanecerem sentados com a cabeça em hiperextensão máxima. Os materiais utilizados foram um compasso e uma régua de 20cm. RESULTADOS: A obtenção das medidas se mostrou ser de fácil realização e não apresentou qualquer tipo de desconforto aos participantes. Houve diferença estatisticamente significante entre os sexos feminino e masculino quanto à posição vertical da laringe, sendo que as mulheres apresentaram a laringe em posição mais alta que os homens. A posição vertical da laringe foi de fácil obtenção e parece ser um parâmetro muito interessante no acompanhamento clínico intra-sujeitos.AIM: The purpose of this research is to propose a procedure to measure the vertical larynx position in the neck at rest in young adults without vocal complaint. STUDY DESIGN: Transversal cohort study. MATERIAL AND METHOD: There were 68 subjects, aged between 18 to 44 years, 33 female and 35 male. The anatomical landmarks used for this research study were the right and left jaw angle (RJA and LJA, the centre of the cricoid arch cartilage (CC and the centre of the sternal furculum (SF. In order to obtain the measures, the subjects were asked to be sitting still with their heads stretched up to the highest possible position. The devices used were a drawing compass and a 20-centimeter ruler. RESULTS: The measurement procedure

Neonatal Anaplasma platys infection in puppies: Further evidence for possible vertical transmission

Czech Academy of Sciences Publication Activity Database

Matei, I.A.; Stuen, S.; Modrý, David; Degan, A.; D'Amico, G.; Mihalca, A. D.

2017-01-01

Roč. 219, 1 January (2017), s. 40-41 ISSN 1090-0233 Institutional support: RVO:60077344 Keywords : Anaplasma platys * canine * vertical transmission Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine OBOR OECD: Veterinary science Impact factor: 1.802, year: 2016

The Effects of Objective and Subjective Socioeconomic Status on Subjective Well-Being among Rural-to-Urban Migrants in China: The Moderating Role of Subjective Social Mobility

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Silin Huang

2017-05-01

Full Text Available Although previous investigations have agreed that Chinese rural-to-urban migrants’ socioeconomic status (SES increases with their migration, the association between SES and subjective well-being is uncertain. To address this research gap, the present study proposed that the association between objective SES and subjective well-being is mediated by subjective SES. This model was tested with a sample of 432 Chinese rural-to-urban migrants. The results indicate a significant association between objective SES and subjective well-being and a partial mediating effect of subjective SES. Furthermore, subjective social mobility, which is one’s expectation about the possibility to move upward in the social hierarchy, was found to moderate both the direct path from objective SES to subjective well-being and the indirect path from subjective SES to subjective well-being. These findings suggest that Chinese rural-to-urban migrants gained in subjective well-being not only because of direct financial achievement but also because of their perceptions and beliefs about their relative social status.

Vertical axis wind turbines

Science.gov (United States)

Krivcov, Vladimir [Miass, RU; Krivospitski, Vladimir [Miass, RU; Maksimov, Vasili [Miass, RU; Halstead, Richard [Rohnert Park, CA; Grahov, Jurij [Miass, RU

2011-03-08

A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

Perception of illusory contour figures: Microgenetic analysis

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Gvozdenović Vasilije P.

2004-01-01

Full Text Available Microgenetic analysis was used to investigate perception of illusory contour figures which represent whole, completed forms on the basis of segmented, incomplete stimulation. The analysis provided an experimental approach to this phenomenon which was standardly investigated phenomenologically. Experimental procedure consisted of two phases: a priming phase and b test phase which consisted of visual search task. Two types of visual search tasks were applied: (i classic detection, in which subjects were detecting presence or absence of the target stimuli and (ii two-alternative forced choice, 2AFC, in which subjects performed discrimination between two concurrent targets (target A vs. target B. Variation of exposition of prim stimuli was used as an indication of the percept formation period. Concepts like early vision, visual attention and feature binding were investigated. Four experiments were conducted. Their outcome showed that (i perception of amodal figure requires visual attention, (ii features binding precedes spatial attention and (iii time period of percept formation is dependent of task properties and varies between 50 - 150 ms. Some results obtained in this research could be explained by feature-integration theory (Treisman & Gelade, 1980; Treisman, 1986. Furthermore, percept formation period data comply with data acquired in Elliott & Müller's psychophysical research (1998.

Illness perception, risk perception and health promotion self-care behaviors among Chinese patient with type 2 diabetes: A cross-sectional survey.

Science.gov (United States)

Nie, Rong; Han, Yanhong; Xu, Jiaqi; Huang, Qiao; Mao, Jing

2018-02-01

To explore illness perception and perceived risk of developing diabetes complications in relation to health-promoting self-care behaviors among Chinese patients with type 2 diabetes. Illness and risk perceptions are important determinants of various health behaviors. However, few studies have simultaneously examined the impacts of these two constructs on self-care among diabetic patients. Data were collected on participants' characteristics, illness perception, risk perception, and health-promoting self-care behaviors over 6months among 304 subjects from three general hospitals. Significant associations between illness perception and risk perception were observed. Illness perception and/or risk perception explained an independent, small but significant proportion of the variance in each health-promoting self-care behavior. One's perceptions of illness and future risk might be influential in understanding health-promoting self-care among diabetic patients. It may be useful to improve self-management by tailoring intervention content to individuals' illness-related perceptions. Copyright © 2017 Elsevier Inc. All rights reserved.

Asymmetric vestibular stimulation reveals persistent disruption of motion perception in unilateral vestibular lesions.

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Panichi, R; Faralli, M; Bruni, R; Kiriakarely, A; Occhigrossi, C; Ferraresi, A; Bronstein, A M; Pettorossi, V E

2017-11-01

Self-motion perception was studied in patients with unilateral vestibular lesions (UVL) due to acute vestibular neuritis at 1 wk and 4, 8, and 12 mo after the acute episode. We assessed vestibularly mediated self-motion perception by measuring the error in reproducing the position of a remembered visual target at the end of four cycles of asymmetric whole-body rotation. The oscillatory stimulus consists of a slow (0.09 Hz) and a fast (0.38 Hz) half cycle. A large error was present in UVL patients when the slow half cycle was delivered toward the lesion side, but minimal toward the healthy side. This asymmetry diminished over time, but it remained abnormally large at 12 mo. In contrast, vestibulo-ocular reflex responses showed a large direction-dependent error only initially, then they normalized. Normalization also occurred for conventional reflex vestibular measures (caloric tests, subjective visual vertical, and head shaking nystagmus) and for perceptual function during symmetric rotation. Vestibular-related handicap, measured with the Dizziness Handicap Inventory (DHI) at 12 mo correlated with self-motion perception asymmetry but not with abnormalities in vestibulo-ocular function. We conclude that 1 ) a persistent self-motion perceptual bias is revealed by asymmetric rotation in UVLs despite vestibulo-ocular function becoming symmetric over time, 2 ) this dissociation is caused by differential perceptual-reflex adaptation to high- and low-frequency rotations when these are combined as with our asymmetric stimulus, 3 ) the findings imply differential central compensation for vestibuloperceptual and vestibulo-ocular reflex functions, and 4 ) self-motion perception disruption may mediate long-term vestibular-related handicap in UVL patients. NEW & NOTEWORTHY A novel vestibular stimulus, combining asymmetric slow and fast sinusoidal half cycles, revealed persistent vestibuloperceptual dysfunction in unilateral vestibular lesion (UVL) patients. The compensation of

Sweating, thirst perception and plasma electrolyte composition in ...

African Journals Online (AJOL)

Thirst is a perception, the subjective experience evoked by fluid deficits. Exercise induces sweating and subsequently electrolyte loss and thirst but there is little documented on post exercise thirst perception in women of varying body mass indices. 40 apparently healthy young women (19-25years) in the follicular phase of ...

Barbell deadlift training increases the rate of torque development and vertical jump performance in novices.

Science.gov (United States)

Thompson, Brennan J; Stock, Matt S; Shields, JoCarol E; Luera, Micheal J; Munayer, Ibrahim K; Mota, Jacob A; Carrillo, Elias C; Olinghouse, Kendra D

2015-01-01

The primary purpose of this study was to examine the effects of 10 weeks of barbell deadlift training on rapid torque characteristics of the knee extensors and flexors. A secondary aim was to analyze the relationships between training-induced changes in rapid torque and vertical jump performance. Fifty-four subjects (age, mean ± SD = 23 ± 3 years) were randomly assigned to a control (n = 20) or training group (n = 34). Subjects in the training group performed supervised deadlift training twice per week for 10 weeks. All subjects performed isometric strength testing of the knee extensors and flexors and vertical jumps before and after the intervention. Torque-time curves were used to calculate rate of torque development (RTD) values at peak and at 50 and 200 milliseconds from torque onset. Barbell deadlift training induced significant pre- to post-increases of 18.8-49.0% for all rapid torque variables (p torque capacities in both the knee extensors and flexors. Changes in rapid torque were associated with improvements in vertical jump height, suggesting a transfer of adaptations from deadlift training to an explosive, performance-based task. Professionals may use these findings when attempting to design effective, time-efficient resistance training programs to improve explosive strength capacities in novices.

vertical bar Vub vertical bar from exclusive semileptonic B→π decays

International Nuclear Information System (INIS)

Flynn, Jonathan M.; Nieves, Juan

2007-01-01

We use Omnes representations of the form factors f + and f 0 for exclusive semileptonic B→π decays, paying special attention to the treatment of the B* pole and its effect on f + . We apply them to combine experimental partial branching fraction information with theoretical calculations of both form factors to extract vertical bar V ub vertical bar. The precision we achieve is competitive with the inclusive determination and we do not find a significant discrepancy between our result, vertical bar V ub vertical bar=(3.90+/-0.32+/-0.18)x10 -3 , and the inclusive world average value (4.45+/-0.20+/-0.26)x10 -3 [Heavy Flavor Averaging Group (HFAG), hep-ex/0603003

A brain electrophysiological correlate of depth perception

International Nuclear Information System (INIS)

Akay, Ahmet; Celebi, Gurbuz

2009-01-01

To investigate brain electrical activity accompanying depth perception using random-dot stereograms. Additional experiments were conducted to ascertain the specificity of this potential to depth perception. In the present study, we performed 3 different and independent experiments on 34 subjects to establish the relationship between depth perception and its cortical electrophysiological correlate. Visual evoked potentials in response to visual stimulation by random-dot stereograms were recorded. To achieve this goal, a data acquisition and analysis system, different from common visual evoked potential recording systems, consisting of 2 personal computers, was used. One of the computers was used to generate the visual stimulus patterns and the other to record and digitally average the potentials evoked by the stimuli. This study was carried out at the Department of Biophysics of Ege University Medical School, Izmir, Turkey, from April to December, 2006. A negative potential component, which is thought to arise in association with depth perception, was recorded from the occipital region from 30 of the 34 subjects. Typically, it had a mean latency of 211.46 ms and 6.40 micron V amplitude. The negative potential is related to depth perception, as this component is present in the responses to stimulus, which carries disparity information but is absent when the stimulus is switched to no disparity information. Additional experiments also showed that the specificity of this component to depth perception becomes evident beyond doubt. (author)

Hazard perception, risk perception, and the need for decontamination by residents exposed to soil pollution: the role of sustainability and the limits of expert knowledge.

Science.gov (United States)

Vandermoere, Frédéric

2008-04-01

This case study examines the hazard and risk perception and the need for decontamination according to people exposed to soil pollution. Using an ecological-symbolic approach (ESA), a multidisciplinary model is developed that draws upon psychological and sociological perspectives on risk perception and includes ecological variables by using data from experts' risk assessments. The results show that hazard perception is best predicted by objective knowledge, subjective knowledge, estimated knowledge of experts, and the assessed risks. However, experts' risk assessments induce an increase in hazard perception only when residents know the urgency of decontamination. Risk perception is best predicted by trust in the risk management. Additionally, need for decontamination relates to hazard perception, risk perception, estimated knowledge of experts, and thoughts about sustainability. In contrast to the knowledge deficit model, objective and subjective knowledge did not significantly relate to risk perception and need for decontamination. The results suggest that residents can make a distinction between hazards in terms of the seriousness of contamination on the one hand, and human health risks on the other hand. Moreover, next to the importance of social determinants of environmental risk perception, this study shows that the output of experts' risk assessments-or the objective risks-can create a hazard awareness rather than an alarming risk consciousness, despite residents' distrust of scientific knowledge.

The acute effects of back squats on vertical jump performance in men and women.

Science.gov (United States)

Witmer, Chad A; Davis, Shala E; Moir, Gavin L

2010-01-01

The aim of the present study was to investigate the acute effects of performing back squats on subsequent performance during a series of vertical jumps in men and women. Twelve men and 12 women were tested on three separate occasions, the first of which was used to determine their 1-repetition maximum (1-RM) parallel back squat. Following this, subjects performed a potentiation and a control treatment in a counterbalanced order. The potentiation treatment culminated with subjects performing parallel back squats with a load equivalent to 70% 1- RM for three repetitions, following which they performed one countermovement vertical jump (CMJ) for maximal height every three minutes for a total of 10 jumps. During the control treatment, subjects performed only the CMJs. Jump height (JH) and vertical stiffness (VStiff) were calculated for each jump from the vertical force signal recorded from a force platform. There were no significant changes in JH or VStiff following the treatments and no significant differences in the responses between men and women (p > 0.05). Correlations between normalized 1-RM back squat load and the absolute change in JH and VStiff were small to moderate for both men and women, with most correlations being negative. Large variations in response to the back squats were noted in both men and women. The use of resistance exercises performed prior to a series of vertical jumps can result in improvements in performance in certain individuals, although the gains tend to be small and dependent upon the mechanical variable measured. There does not seem to be any differences between men and women in the response to dynamic potentiation protocols. Key pointsSubstantial individual responses were noted in both men and women in response to the PAP protocol used in the present study.The choice of dependent variable influences the ef-ficacy of the PAP protocol, with JH and VStiff demonstrating disparate responses in individual sub-jects.Such individual responses

Spiral density waves and vertical circulation in protoplanetary discs

Science.gov (United States)

Riols, A.; Latter, H.

2018-06-01

Spiral density waves dominate several facets of accretion disc dynamics - planet-disc interactions and gravitational instability (GI) most prominently. Though they have been examined thoroughly in two-dimensional simulations, their vertical structures in the non-linear regime are somewhat unexplored. This neglect is unwarranted given that any strong vertical motions associated with these waves could profoundly impact dust dynamics, dust sedimentation, planet formation, and the emissivity of the disc surface. In this paper, we combine linear calculations and shearing box simulations in order to investigate the vertical structure of spiral waves for various polytropic stratifications and wave amplitudes. For sub-adiabatic profiles, we find that spiral waves develop a pair of counter-rotating poloidal rolls. Particularly strong in the non-linear regime, these vortical structures issue from the baroclinicity supported by the background vertical entropy gradient. They are also intimately connected to the disc's g modes which appear to interact non-linearly with the density waves. Furthermore, we demonstrate that the poloidal rolls are ubiquitous in gravitoturbulence, emerging in the vicinity of GI spiral wakes, and potentially transporting grains off the disc mid-plane. Other than hindering sedimentation and planet formation, this phenomena may bear on observations of the disc's scattered infrared luminosity. The vortical features could also impact on the turbulent dynamo operating in young protoplanetary discs subject to GI, or possibly even galactic discs.

The role of sleep in aesthetic perception and empathy: A mediation analysis.

Science.gov (United States)

Peretti, Sara; Tempesta, Daniela; Socci, Valentina; Pino, Maria C; Mazza, Monica; Valenti, Marco; De Gennaro, Luigi; Di Dio, Cinzia; Marchetti, Antonella; Ferrara, Michele

2018-02-06

The ability to experience aesthetics plays a fundamental role in human social interactions, as well as the capacity to feel empathy. Some studies have shown that beauty perception shares part of the neural network underlying emotional and empathic abilities, which are also known to affect sleep quality and duration. In this study, we evaluated for the first time the effects of sleep on the relation between aesthetic perception and empathic abilities in healthy subjects using a mediation analysis approach. One-hundred and twenty-six subjects participated in this study. One-hundred and one subjects slept at home (Sleep Group). The remaining 25 subjects were tested as controls after 1 night of sleep deprivation to assess the effects of lack of sleep on aesthetic perception and empathy (Sleep-Deprived Group). All participants underwent one testing session in which they performed a battery of empathy tests and an aesthetic perception task (Golden Beauty). The results showed that sleep duration mediates the relationship between empathy and aesthetic perception in the sleep group. The mediation effect of sleep was more evident on the emotional empathy measures. Conversely, in the sleep deprivation group the lack of correlations among empathy, aesthetic perception and sleep variables did not allow to perform the mediation analysis. These results suggest that adequate sleep duration may play a significant role in improving cognitive and emotional empathic abilities as well as the capability to give accurate aesthetic judgements. © 2018 European Sleep Research Society.

Elementary Schoolchildren's Self- and Social Perceptions of Success

Science.gov (United States)

Määttä, Elina; Mykkänen, Arttu; Järvelä, Sanna

2016-01-01

The purpose of this study was to investigate children's self- and social perceptions of success to identify how success could be promoted in a classroom context. Using a participatory approach, this study explored children's subjective experiences with success in 41 learning situations selected by researchers (Phase 1: self-perceptions) and 48…

Phantom auditory perception (tinnitus): mechanisms of generation and perception.

Science.gov (United States)

Jastreboff, P J

1990-08-01

Phantom auditory perception--tinnitus--is a symptom of many pathologies. Although there are a number of theories postulating certain mechanisms of its generation, none have been proven yet. This paper analyses the phenomenon of tinnitus from the point of view of general neurophysiology. Existing theories and their extrapolation are presented, together with some new potential mechanisms of tinnitus generation, encompassing the involvement of calcium and calcium channels in cochlear function, with implications for malfunction and aging of the auditory and vestibular systems. It is hypothesized that most tinnitus results from the perception of abnormal activity, defined as activity which cannot be induced by any combination of external sounds. Moreover, it is hypothesized that signal recognition and classification circuits, working on holographic or neuronal network-like representation, are involved in the perception of tinnitus and are subject to plastic modification. Furthermore, it is proposed that all levels of the nervous system, to varying degrees, are involved in tinnitus manifestation. These concepts are used to unravel the inexplicable, unique features of tinnitus and its masking. Some clinical implications of these theories are suggested.

Depressive realism: evidence from false interpersonal perception.

Science.gov (United States)

Yeh, Zai-Ting; Liu, Shen-Ing

2007-04-01

The present study examined the depressive realism hypothesis, which posits that depressed people are often more accurate in their perceptions and judgments than non-depressed people are. Each subject initially generated descriptions of others important to them, both positive and negative important others, in the pretest section, and 3 or 4 weeks later, some subjects were invited into the formal experiment to measure the accuracy of their perceptions in a pseudo-social interaction situation. A total of 52 patients diagnosed with clinical depression and 62 normal matched subjects participated in the experimental procedure. The results indicate that clinically depressed patients provided more accurate, less distorted descriptions of their positive important others than did those in the normal group. However, when information involved the negative important others, the results exhibited a trend, but these results did not provide significant support for the depressive realism hypothesis. The results support the depressive realism hypothesis when tasks involve subjects' own positive important others.

Rotation of vertically oriented objects during earthquakes

Science.gov (United States)

Hinzen, Klaus-G.

2012-10-01

Vertically oriented objects, such as tombstones, monuments, columns, and stone lanterns, are often observed to shift and rotate during earthquake ground motion. Such observations are usually limited to the mesoseismal zone. Whether near-field rotational ground motion components are necessary in addition to pure translational movements to explain the observed rotations is an open question. We summarize rotation data from seven earthquakes between 1925 and 2009 and perform analog and numeric rotation testing with vertically oriented objects. The free-rocking motion of a marble block on a sliding table is disturbed by a pulse in the direction orthogonal to the rocking motion. When the impulse is sufficiently strong and occurs at the `right' moment, it induces significant rotation of the block. Numeric experiments of a free-rocking block show that the initiation of vertical block rotation by a cycloidal acceleration pulse applied orthogonal to the rocking axis depends on the amplitude of the pulse and its phase relation to the rocking cycle. Rotation occurs when the pulse acceleration exceeds the threshold necessary to provoke rocking of a resting block, and the rocking block approaches its equilibrium position. Experiments with blocks subjected to full 3D strong motion signals measured during the 2009 L'Aquila earthquake confirm the observations from the tests with analytic ground motions. Significant differences in the rotational behavior of a monolithic block and two stacked blocks exist.

Reward modulates perception in binocular rivalry.

Science.gov (United States)

Marx, Svenja; Einhäuser, Wolfgang

2015-01-14

Our perception does not provide us with an exact imprint of the outside world, but is continuously adapted to our internal expectations, task sets, and behavioral goals. Although effects of reward-or value in general-on perception therefore seem likely, how valuation modulates perception and how such modulation relates to attention is largely unknown. We probed effects of reward on perception by using a binocular-rivalry paradigm. Distinct gratings drifting in opposite directions were presented to each observer's eyes. To objectify their subjective perceptual experience, the optokinetic nystagmus was used as measure of current perceptual dominance. In a first experiment, one of the percepts was either rewarded or attended. We found that reward and attention similarly biased perception. In a second experiment, observers performed an attentionally demanding task either on the rewarded stimulus, the other stimulus, or both. We found that-on top of an attentional effect on perception-at each level of attentional load, reward still modulated perception by increasing the dominance of the rewarded percept. Similarly, penalizing one percept increased dominance of the other at each level of attentional load. In turn, rewarding-and similarly nonpunishing-a percept yielded performance benefits that are typically associated with selective attention. In conclusion, our data show that value modulates perception in a similar way as the volitional deployment of attention, even though the relative effect of value is largely unaffected by an attention task. © 2015 ARVO.

The WZNW model on PSU(1, 1 vertical stroke 2)

International Nuclear Information System (INIS)

Goetz, G.

2006-10-01

According to the work of Berkovits, Vafa and Witten, the non-linear sigma model on the supergroup PSU(1,1 vertical stroke 2) is the essential building block for string theory on AdS 3 xS 3 xT 4 . Models associated with a non-vanishing value of the RR flux can be obtained through a psu(1,1 vertical stroke 2) invariant marginal deformation of the WZNW model on PSU(1,1 vertical stroke 2). We take this as a motivation to present a manifestly psu(1,1 vertical stroke 2) covariant construction of the model at the Wess-Zumino point, corresponding to a purely NSNS background 3-form flux. At this point the model possesses an enhanced psu(1,1 vertical stroke 2) current algebra symmetry whose representation theory, including explicit character formulas, is developed systematically in the first part of the paper. The space of vertex operators and a free fermion representation for their correlation functions is our main subject in the second part. Contrary to a widespread claim, bosonic and fermionic fields are necessarily coupled to each other. The interaction changes the supersymmetry transformations, with drastic consequences for the multiplets of localized normalizable states in the model. It is only this fact which allows us to decompose the full state space into multiplets of the global supersymmetry. We analyze these decompositions systematically as a preparation for a forthcoming study of the RR deformation. (orig.)

The WZNW model on PSU(1, 1 vertical stroke 2)

Energy Technology Data Exchange (ETDEWEB)

Goetz, G. [CEA Centre d' Etudes de Saclay, 91 - Gif-sur-Yvette (France). Service de Physique Theorique; Quella, T. [King' s College London (United Kingdom). Dept. of Mathematics]|[Amsterdam Univ. (Netherlands). KdV Institute for Mathematics; Schomerus, V. [CEA Centre d' Etudes de Saclay, 91 - Gif-sur-Yvette (France). Service de Physique Theorique]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2006-10-15

According to the work of Berkovits, Vafa and Witten, the non-linear sigma model on the supergroup PSU(1,1 vertical stroke 2) is the essential building block for string theory on AdS{sub 3}xS{sup 3}xT{sup 4}. Models associated with a non-vanishing value of the RR flux can be obtained through a psu(1,1 vertical stroke 2) invariant marginal deformation of the WZNW model on PSU(1,1 vertical stroke 2). We take this as a motivation to present a manifestly psu(1,1 vertical stroke 2) covariant construction of the model at the Wess-Zumino point, corresponding to a purely NSNS background 3-form flux. At this point the model possesses an enhanced psu(1,1 vertical stroke 2) current algebra symmetry whose representation theory, including explicit character formulas, is developed systematically in the first part of the paper. The space of vertex operators and a free fermion representation for their correlation functions is our main subject in the second part. Contrary to a widespread claim, bosonic and fermionic fields are necessarily coupled to each other. The interaction changes the supersymmetry transformations, with drastic consequences for the multiplets of localized normalizable states in the model. It is only this fact which allows us to decompose the full state space into multiplets of the global supersymmetry. We analyze these decompositions systematically as a preparation for a forthcoming study of the RR deformation. (orig.)

On the concepts of inwardness and subjectivity in Shakespeare's work

Directory of Open Access Journals (Sweden)

Carlos Roberto Ludwig

2016-12-01

Full Text Available This essay aims at discussing the concepts of subjectivity and inwardness in Early Renaissance. The issue discussed in this research is to take into account that both concepts are interchangeable, since they represent distinct notions of the similar phenomenon: the inner space of sensations, emotions, feelings, and identity. The concept of identity was associated to the perception of an inner space of the subject in the 16th and 17th centuries. It was always compared and defined parting from the notion of physical and gestural appearances, whose discursive forms were always based on the perceptive movement from the outward to the inward space of the subject. On the other hand, subjectivity is a modern concept which emerges from the 19th onward whose discursive forms part form the inner space of the subject, without taking into consideration the physical and gestural appearances. This research is bibliographic and uses some examples from the dramaturg William Shakespeare. As it was observed, the concepts of subjectivity and inwardness are not synonyms, once they part from distinct philosophic and psychologic perspectives, besides that they are still perceive until our times.

Ecosecent:: Essence, Subject and Structure

Directory of Open Access Journals (Sweden)

Kozachenko Hanna V.

2014-02-01

Full Text Available The article shows that due to multi-laterality the knowledge about security is distributed by various branches, one of which is ecosestate, within which conditions of secure functioning of socio-economic systems and methods of their provision are studied. It shows the essence of ecosecent as a component of the “state – region (branch – subject of economic activity” ecosestate vertical – a set of knowledge about economic security of subjects of economic activity. It considers reasons that cause establishment of ecosecent: practical needs and a necessity to reconsider basic concepts of the essence, limits and factors of economy. It formulates the subject of ecosecent. It considers the status of the “economic security of the subject of economic activity” notion as its state, described with a set of parameters or characteristic features as characteristics of the subject of economic activity as a condition of its activity and as a set of actions that allow ensuring or preservation of the state of security, in other words, protection of the subject of economic activity. It presents general approaches to structuring of ecosecent by activity, functional and branch features.

Neck proprioception shapes body orientation and perception of motion.

Science.gov (United States)

Pettorossi, Vito Enrico; Schieppati, Marco

2014-01-01

This review article deals with some effects of neck muscle proprioception on human balance, gait trajectory, subjective straight-ahead (SSA), and self-motion perception. These effects are easily observed during neck muscle vibration, a strong stimulus for the spindle primary afferent fibers. We first remind the early findings on human balance, gait trajectory, SSA, induced by limb, and neck muscle vibration. Then, more recent findings on self-motion perception of vestibular origin are described. The use of a vestibular asymmetric yaw-rotation stimulus for emphasizing the proprioceptive modulation of motion perception from the neck is mentioned. In addition, an attempt has been made to conjointly discuss the effects of unilateral neck proprioception on motion perception, SSA, and walking trajectory. Neck vibration also induces persistent aftereffects on the SSA and on self-motion perception of vestibular origin. These perceptive effects depend on intensity, duration, side of the conditioning vibratory stimulation, and on muscle status. These effects can be maintained for hours when prolonged high-frequency vibration is superimposed on muscle contraction. Overall, this brief outline emphasizes the contribution of neck muscle inflow to the construction and fine-tuning of perception of body orientation and motion. Furthermore, it indicates that tonic neck-proprioceptive input may induce persistent influences on the subject's mental representation of space. These plastic changes might adapt motion sensitiveness to lasting or permanent head positional or motor changes.

Making sense of perceptions of risk of diseases and vaccinations: a qualitative study combining models of health beliefs, decision-making and risk perception

OpenAIRE

Bond Lyndal; Nolan Terry

2011-01-01

Abstract Background Maintaining high levels of childhood vaccinations is important for public health. Success requires better understanding of parents' perceptions of diseases and consequent decisions about vaccinations, however few studies have considered this from the theoretical perspectives of risk perception and decision-making under uncertainty. The aim of this study was to examine the utility of subjective risk perception and decision-making theories to provide a better understanding o...

Age-related differences between thinning of horizontal and vertical trabeculae in human lumbar bone as assessed by a new computerized method

DEFF Research Database (Denmark)

Thomsen, J.S.; Ebbesen, E.N.; Mosekilde, Li.

2002-01-01

To investigate whether vertical trabeculae undergo compensatory thickening with age in the human vertebral body, a new computerized method was developed that is able to distinguish between horizontal and vertical trabeculae on normal histological sections. Study subjects included 48 individuals (...

Effect of Embedment on the Vertical Bearing Capacity of Bucket Foundations in Clay

DEFF Research Database (Denmark)

Barari, Amin; Ibsen, Lars Bo

2011-01-01

To evaluate the undrained behaviour of bucket foundations installed on Yoldia clay, 100 tests on bucket foundations subject to vertical and moment loadings were conducted at Aalborg university geotechnical centre. Bucket foundations are tubular steel foundations that are installed by sealing...

Linear multivariate evaluation models for spatial perception of soundscape.

Science.gov (United States)

Deng, Zhiyong; Kang, Jian; Wang, Daiwei; Liu, Aili; Kang, Joe Zhengyu

2015-11-01

Soundscape is a sound environment that emphasizes the awareness of auditory perception and social or cultural understandings. The case of spatial perception is significant to soundscape. However, previous studies on the auditory spatial perception of the soundscape environment have been limited. Based on 21 native binaural-recorded soundscape samples and a set of auditory experiments for subjective spatial perception (SSP), a study of the analysis among semantic parameters, the inter-aural-cross-correlation coefficient (IACC), A-weighted-equal sound-pressure-level (L(eq)), dynamic (D), and SSP is introduced to verify the independent effect of each parameter and to re-determine some of their possible relationships. The results show that the more noisiness the audience perceived, the worse spatial awareness they received, while the closer and more directional the sound source image variations, dynamics, and numbers of sound sources in the soundscape are, the better the spatial awareness would be. Thus, the sensations of roughness, sound intensity, transient dynamic, and the values of Leq and IACC have a suitable range for better spatial perception. A better spatial awareness seems to promote the preference slightly for the audience. Finally, setting SSPs as functions of the semantic parameters and Leq-D-IACC, two linear multivariate evaluation models of subjective spatial perception are proposed.

Perception and the temporal properties of speech

Science.gov (United States)

Gordon, Peter C.

1991-11-01

Four experiments addressing the role of attention in phonetic perception are reported. The first experiment shows that the relative importance of two cues to the voicing distinction changes when subjects must perform an arithmetic distractor task at the same time as identifying a speech stimulus. The voice onset time cue loses phonetic significance when subjects are distracted, while the F0 onset frequency cue does not. The second experiment shows a similar pattern for two cues to the distinction between the vowels /i/ (as in 'beat') and /I/ (as in 'bit'). Together these experiments indicate that careful attention to speech perception is necessary for strong acoustic cues to achieve their full phonetic impact, while weaker acoustic cues achieve their full phonetic impact without close attention. Experiment 3 shows that this pattern is obtained when the distractor task places little demand on verbal short term memory. Experiment 4 provides a large data set for testing formal models of the role of attention in speech perception. Attention is shown to influence the signal to noise ratio in phonetic encoding. This principle is instantiated in a network model in which the role of attention is to reduce noise in the phonetic encoding of acoustic cues. Implications of this work for understanding speech perception and general theories of the role of attention in perception are discussed.

Ballistic stretching increases flexibility and acute vertical jump height when combined with basketball activity.

Science.gov (United States)

Woolstenhulme, Mandy T; Griffiths, Christine M; Woolstenhulme, Emily M; Parcell, Allen C

2006-11-01

Stretching is often included as part of a warm-up procedure for basketball activity. However, the efficacy of stretching with respect to sport performance has come into question. We determined the effects of 4 different warm-up protocols followed by 20 minutes of basketball activity on flexibility and vertical jump height. Subjects participated in 6 weeks (2 times per week) of warm-up and basketball activity. The warm-up groups participated in ballistic stretching, static stretching, sprinting, or basketball shooting (control group). We asked 3 questions. First, what effect does 6 weeks of warm-up exercise and basketball play have on both flexibility and vertical jump height? We measured sit and reach and vertical jump height before (week -1) and after (week 7) the 6 weeks. Flexibility increased for the ballistic, static, and sprint groups compared to the control group (p vertical jump height did not change for any of the groups. Our second question was what is the acute effect of each warm-up on vertical jump height? We measured vertical jump immediately after the warm-up on 4 separate occasions during the 6 weeks (at weeks 0, 2, 4, and 6). Vertical jump height was not different for any group. Finally, our third question was what is the acute effect of each warm-up on vertical jump height following 20 minutes of basketball play? We measured vertical jump height immediately following 20 minutes of basketball play at weeks 0, 2, 4, and 6. Only the ballistic stretching group demonstrated an acute increase in vertical jump 20 minutes after basketball play (p basketball play, as it is beneficial to vertical jump performance.

Sensory perception and pleasantness of food flavour in elderly subjects.

NARCIS (Netherlands)

Graaf, de C.; Polet, P.; Staveren, van W.A.

1994-01-01

This study was designed to determine the perceived intensity and pleasantness of different food flavors. A group of 32 young subjects (mean age: 22, range 20-25) and 23 elderly subjects (mean age: 76, range 72-82) judged the intensity and the pleasantness of five series of food flavors, each with

Effects of Sleeve Gastrectomy vs. Roux-en-Y Gastric Bypass on Eating Behavior and Sweet Taste Perception in Subjects with Obesity

Directory of Open Access Journals (Sweden)

Katie Nance

2017-12-01

Full Text Available The goal of this study was to test the hypothesis that weight loss induced by Roux-en-Y gastric bypass (RYGB has greater effects on taste perception and eating behavior than comparable weight loss induced by sleeve gastrectomy (SG. We evaluated the following outcomes in 31 subjects both before and after ~20% weight loss induced by RYGB (n = 23 or SG (n = 8: (1 sweet, savory, and salty taste sensitivity; (2 the most preferred concentrations of sucrose and monosodium glutamate; (3 sweetness palatability, by using validated sensory testing techniques; and (4 eating behavior, by using the Food Craving Inventory and the Dutch Eating Behavior Questionnaire. We found that neither RYGB nor SG affected sweetness or saltiness sensitivity. However, weight loss induced by either RYGB or SG caused the same decrease in: (1 frequency of cravings for foods; (2 influence of emotions and external food cues on eating behavior; and (3 shifted sweetness palatability from pleasant to unpleasant when repetitively tasting sucrose (all p-values ≤ 0.01. Therefore, when matched on weight loss, SG and RYGB cause the same beneficial effects on key factors involved in the regulation of eating behavior and hedonic component of taste perception.

Contribution of eye position to movement perception.

Science.gov (United States)

Pettorossi, V E; Panichi, R; Bambagioni, D; Grassi, S; Botti, F M

2004-05-01

To investigate the influence of gaze eccentricity on movement perception during asymmetric vestibular stimulation. Subjects (n = 10) were placed on a rotating platform and oscillated asymmetrically in the dark. Subjects were asked to reproduce with a pointer the location in space of a light spot that was turned off at the beginning of the oscillation. The target was presented in centric and eccentric (0 degrees, 20 degrees and 40 degrees) positions. In the centric position a large shift from the real position of the target was observed in the opposite direction to that of the faster vestibular stimulation. The shift increased when the target was placed eccentrically toward the slower vestibular stimulation side and decreased when it was placed in the opposite direction. The dependence of rotation perception on the target position suggests that the eye deviation, imposed by the eccentricity of the target, is able to influence the perception of body movement and may modulate the internal reference frame.

Assessment of Body perception, Psychological Distress, and ...

African Journals Online (AJOL)

Background: Obesity can lead to psychological, social, and medical problems that may negatively affect the quality of life Aim: In our study, we aimed to evaluate the body perception, psychological distress, and subjective quality of life of obese subjects in comparison with normal weighted ones. Methods: A total of 494 ...

Binocular perception of slant about oblique axes relative to a visual frame of reference

NARCIS (Netherlands)

Ee, R. van; Erkelens, Casper J.

1995-01-01

From the literature it is known that the processing of disparity for slant is different in the presence and in the absence of a visual frame of reference. We elaborate the experimental finding that vertical disparity is not processed for slant perception in the presence of a visual reference. This

Subjectivity in Design Education: The Perception of the City through Personal Maps

Science.gov (United States)

Yilmaz, Ebru

2016-01-01

Our mental maps related to the cities are limited by our personal perception and fragmented in the process. There are many inner and outer effects that shape our mental maps, and as a result the fragmented whole refers to the total city image in our minds. To represent this image, an experimental study has been conducted with a group of students.…

Students helping students: vertical peer mentoring to enhance the medical school experience.

Science.gov (United States)

Andre, Christine; Deerin, Jessica; Leykum, Luci

2017-05-02

Effective mentoring is an important component of medical student professional development. We provide a description of the mentoring program at our institution. Our institution UTHSCSA implemented a student-advising program (Veritas) with clinical faculty mentors and senior students (MiMs). The MiMs provided vertical peer mentoring to more junior students as an adjunct to faculty advising. The MiMs lead small group discussions that foster camaraderie, share academic and career information and promote professional identity. An optional MiM elective more intensively develops mentorship and leadership skills through a formal curriculum. The authors used annual survey data of all students as well as student mentors to evaluate program effectiveness. Overall, student perception of the program improved each year across multiple domains, including feeling more prepared, supported and satisfied with their overall experience in medical school. Student mentors also found the process rewarding and helpful to their future careers as physicians. The authors suggest implementing a vertical peer-mentoring program can be an effective adjunct to faculty mentoring.

New solutions for the short-time analysis of geothermal vertical boreholes

Energy Technology Data Exchange (ETDEWEB)

Lamarche, Louis; Beauchamp, Benoit [Ecole de Technologie Supereure, 1100 Notre-Dame Ouest, Montreal (Canada)

2007-04-15

Many models, either numerical or analytical, have been proposed to analyse the thermal response of vertical heat exchangers that are used in ground coupled heat pump systems (GCHP). In both approaches, most of the models are valid after few hours of operation since they neglect the heat capacity of the borehole. This is valid for design purposes, where the time of interest is in the order of months and years. Recently, the short time response of vertical boreholes became a subject of interest. In this paper, we present a new analytical approach to treat this problem. It solves the exact solution for concentric cylinders and is a good approximation for the familiar U-tube configuration. (author)

Speech perception with mono- and quadrupolar electrode configurations: a crossover study.

NARCIS (Netherlands)

Mens, L.H.M.; Berenstein, C.K.

2005-01-01

OBJECTIVE: To study the effect of two multipolar electrode configurations on speech perception, pitch perception, and the intracochlear electrical field. STUDY DESIGN: Crossover design; within subject. SETTING: Tertiary referral center. PATIENTS: Eight experienced adult cochlear implant users.

Patient and physician perception of natural orifice transluminal endoscopic appendectomy

Czech Academy of Sciences Publication Activity Database

Hucl, T.; Saglová, A.; Beneš, M.; Kocík, M.; Oliverius, M.; Valenta, Zdeněk; Špičák, J.

2012-01-01

Roč. 18, č. 15 (2012), s. 1800-1805 ISSN 1007-9327 Institutional research plan: CEZ:AV0Z10300504 Keywords : natural orifice transluminal endoscopic surgery * patient perception * physician perception * appendectomy * laparoscopy Subject RIV: FJ - Surgery incl. Transplants Impact factor: 2.547, year: 2012

Everyday listening questionnaire: correlation between subjective hearing and objective performance.

Science.gov (United States)

Brendel, Martina; Frohne-Buechner, Carolin; Lesinski-Schiedat, Anke; Lenarz, Thomas; Buechner, Andreas

2014-01-01

Clinical experience has demonstrated that speech understanding by cochlear implant (CI) recipients has improved over recent years with the development of new technology. The Everyday Listening Questionnaire 2 (ELQ 2) was designed to collect information regarding the challenges faced by CI recipients in everyday listening. The aim of this study was to compare self-assessment of CI users using ELQ 2 with objective speech recognition measures and to compare results between users of older and newer coding strategies. During their regular clinical review appointments a group of representative adult CI recipients implanted with the Advanced Bionics implant system were asked to complete the questionnaire. The first 100 patients who agreed to participate in this survey were recruited independent of processor generation and speech coding strategy. Correlations between subjectively scored hearing performance in everyday listening situations and objectively measured speech perception abilities were examined relative to the speech coding strategies used. When subjects were grouped by strategy there were significant differences between users of older 'standard' strategies and users of the newer, currently available strategies (HiRes and HiRes 120), especially in the categories of telephone use and music perception. Significant correlations were found between certain subjective ratings and the objective speech perception data in noise. There is a good correlation between subjective and objective data. Users of more recent speech coding strategies tend to have fewer problems in difficult hearing situations.

Early stages of figure-ground segregation during perception of the face-vase.

Science.gov (United States)

Pitts, Michael A; Martínez, Antígona; Brewer, James B; Hillyard, Steven A

2011-04-01

The temporal sequence of neural processes supporting figure-ground perception was investigated by recording ERPs associated with subjects' perceptions of the face-vase figure. In Experiment 1, subjects continuously reported whether they perceived the face or the vase as the foreground figure by pressing one of two buttons. Each button press triggered a probe flash to the face region, the vase region, or the borders between the two. The N170/vertex positive potential (VPP) component of the ERP elicited by probes to the face region was larger when subjects perceived the faces as figure. Preceding the N170/VPP, two additional components were identified. First, when the borders were probed, ERPs differed in amplitude as early as 110 msec after probe onset depending on subjects' figure-ground perceptions. Second, when the face or vase regions were probed, ERPs were more positive (at ∼ 150-200 msec) when that region was perceived as figure versus background. These components likely reflect an early "border ownership" stage, and a subsequent "figure-ground segregation" stage of processing. To explore the influence of attention on these stages of processing, two additional experiments were conducted. In Experiment 2, subjects selectively attended to the face or vase region, and the same early ERP components were again produced. In Experiment 3, subjects performed an identical selective attention task, but on a display lacking distinctive figure-ground borders, and neither of the early components were produced. Results from these experiments suggest sequential stages of processing underlying figure-ground perception, each which are subject to modifications by selective attention.

Isolating neural correlates of conscious perception from neural correlates of reporting one’s perception

Directory of Open Access Journals (Sweden)

Michael A Pitts

2014-10-01

Full Text Available To isolate neural correlates of conscious perception (NCCs, a standard approach has been to contrast neural activity elicited by identical stimuli of which subjects are aware versus unaware. Because conscious experience is private, determining whether a stimulus was consciously perceived requires subjective report: e.g., button-presses indicating detection, visibility ratings, verbal reports, etc. This reporting requirement introduces a methodological confound when attempting to isolate NCCs: The neural processes responsible for accessing and reporting one’s percept are difficult to distinguish from those underlying the conscious percept itself. Here, we review recent attempts to circumvent this issue via a modified inattentional blindness paradigm (Pitts, Martinez, & Hillyard, 2012 and present new data from a backward masking experiment in which task-relevance and visual awareness were manipulated in a 2x2 crossed design. In agreement with our previous inattentional blindness results, stimuli that were consciously perceived yet not immediately accessed for report (aware, task-irrelevant condition elicited a mid-latency posterior ERP negativity (~200-240ms, while stimuli that were accessed for report (aware, task-relevant condition elicited additional components including a robust P3b (~380-480ms subsequent to the mid-latency negativity. Overall, these results suggest that some of the NCCs identified in previous studies may be more closely linked with accessing and maintaining perceptual information for reporting purposes than with encoding the conscious percept itself. An open question is whether the remaining NCC candidate (the ERP negativity at 200-240ms reflects visual awareness or object-based attention.

Modeling Relationships Between Flight Crew Demographics and Perceptions of Interval Management

Science.gov (United States)

Remy, Benjamin; Wilson, Sara R.

2016-01-01

The Interval Management Alternative Clearances (IMAC) human-in-the-loop simulation experiment was conducted to assess interval management system performance and participants' acceptability and workload while performing three interval management clearance types. Twenty-four subject pilots and eight subject controllers flew ten high-density arrival scenarios into Denver International Airport during two weeks of data collection. This analysis examined the possible relationships between subject pilot demographics on reported perceptions of interval management in IMAC. Multiple linear regression models were created with a new software tool to predict subject pilot questionnaire item responses from demographic information. General patterns were noted across models that may indicate flight crew demographics influence perceptions of interval management.

Determination of the quark coupling strength vertical bar V-ub vertical bar using baryonic decays

NARCIS (Netherlands)

Aaij, R.; Adeva, B.; Adinolfi, M.; Older, A. A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Onderwater, C. J. G.; Pellegrino, A.; Tolk, S.

In the Standard Model of particle physics, the strength of the couplings of the b quark to the u and c quarks, vertical bar V-ub vertical bar and vertical bar V-ub vertical bar, are governed by the coupling of the quarks to the Higgs boson. Using data from the LHCb experiment at the Large Hadron

Non-axisymmetric simulation of the vertical displacement event in tokamaks

International Nuclear Information System (INIS)

Lim, Y.Y.; Lee, J.K.; Shin, K.J.; Hur, M.S.

1999-01-01

Tokamak plasmas with highly elongated cross sections are subject to a vertical displacement event (VDE). The nonlinear magnetohydrodynamic (MHD) evolutions of tokamak plasmas during the VDE are simulated by a three-dimensional MHD code as a combination of N=0 and N=1 components. The nonlinear evolution during the VDE is strongly affected by the relative amplitude of the N=1 to the N=0 modes. (author)

Subjective satisfaction and quality of life in patients prior to listing for liver transplantation.

Science.gov (United States)

Minazzato, L; Amodio, P; Cillo, U; Zanus, G; Schiff, S; Bombonato, G; Salari, A; Bianco, T

2009-01-01

Differences in health-related quality of life (HR-QoL) perception between alcohol abusing and non-substance-dependent subjects with liver cirrhosis could depend on differences in personality profile and influence management of patients awaiting liver transplant. We compared the perceptions of disease state in 78 male patients of similar disease severity divided into 2 groups based on etiology of cirrhosis: 47% had alcoholic cirrhosis, and 53% had hepatitis C virus(HCV)-related cirrhosis without alcohol abuse. Patients' perception of disease state was determined using the SAT-P questionnaire (a self-administered questionnaire that provides a global assessment of perceived HR-QoL and subjective well-being). The assessment yields 2 scales: an analytic scale based on 32 variables and a synthetic scale based on 5 factors. In patients with alcohol-related disease, ''psychological function'' was found to be more impaired,while ''sleep, diet, and free time'' was less impaired compared with subjects with HCV-related cirrhosis, suggesting dysfunction related to substance abuse with personality disturbance. The perception of disease state is different in alcohol-abusing patients with cirrhosis compared with those with cirrhosis unrelated to alcohol.

Analysis of an Irregular RC Multi-storeyed Building Subjected to Dynamic Loading

Science.gov (United States)

AkashRaut; Pachpor, Prabodh; Dautkhani, Sanket

2018-03-01

Many buildings in the present scenario have irregular configurations both in plan and elevation. This in future may subject to devastating earthquakes. So it is necessary to analyze the structure. The present paper is made to study three type of irregularity wiz vertical, mass and plan irregularity as per clause 7.1 of IS 1893 (part1)2002 code. The paper discusses the analysis of RC (Reinforced Concrete) Buildings with vertical irregularity. The study as a whole makes an effort to evaluate the effect of vertical irregularity on RC buildings for which comparison of three parameters namely shear force, bending moment and deflection are taken into account.

Vertical integration

International Nuclear Information System (INIS)

Antill, N.

1999-01-01

This paper focuses on the trend in international energy companies towards vertical integration in the gas chain from wellhead to power generation, horizontal integration in refining and marketing businesses, and the search for larger projects with lower upstream costs. The shape of the petroleum industry in the next millennium, the creation of super-major oil companies, and the relationship between size and risk are discussed. The dynamics of vertical integration, present events and future developments are considered. (UK)

Visual perception of ADHD children with sensory processing disorder.

Science.gov (United States)

Jung, Hyerim; Woo, Young Jae; Kang, Je Wook; Choi, Yeon Woo; Kim, Kyeong Mi

2014-04-01

The aim of the present study was to investigate the visual perception difference between ADHD children with and without sensory processing disorder, and the relationship between sensory processing and visual perception of the children with ADHD. Participants were 47 outpatients, aged 6-8 years, diagnosed with ADHD. After excluding those who met exclusion criteria, 38 subjects were clustered into two groups, ADHD children with and without sensory processing disorder (SPD), using SSP reported by their parents, then subjects completed K-DTVP-2. Spearman correlation analysis was run to determine the relationship between sensory processing and visual perception, and Mann-Whitney-U test was conducted to compare the K-DTVP-2 score of two groups respectively. The ADHD children with SPD performed inferiorly to ADHD children without SPD in the on 3 quotients of K-DTVP-2. The GVP of K-DTVP-2 score was related to Movement Sensitivity section (r=0.368(*)) and Low Energy/Weak section of SSP (r=0.369*). The result of the present study suggests that among children with ADHD, the visual perception is lower in those children with co-morbid SPD. Also, visual perception may be related to sensory processing, especially in the reactions of vestibular and proprioceptive senses. Regarding academic performance, it is necessary to consider how sensory processing issues affect visual perception in children with ADHD.

Vertical dynamics of a single-span beam subjected to moving mass-suspended payload system with variable speeds

Science.gov (United States)

He, Wei

2018-03-01

This paper presents the vertical dynamics of a simply supported Euler-Bernoulli beam subjected to a moving mass-suspended payload system of variable velocities. A planar theoretical model of the moving mass-suspended payload system of variable speeds is developed based on several assumptions: the rope is massless and rigid, and its length keeps constant; the stiffness of the gantry beam is much greater than the supporting beam, and the gantry beam can be treated as a mass particle traveling along the supporting beam; the supporting beam is assumed as a simply supported Bernoulli-Euler beam. The model can be degenerated to consider two classical cases-the moving mass case and the moving payload case. The proposed model is verified using both numerical and experimental methods. To further investigate the effect of possible influential factors, numerical examples are conducted covering a range of parameters, such as variable speeds (acceleration or deceleration), mass ratios of the payload to the total moving load, and the pendulum lengths. The effect of beam flexibility on swing response of the payload is also investigated. It is shown that the effect of a variable speed is significant for the deflections of the beam. The accelerating movement tends to induce larger beam deflections, while the decelerating movement smaller ones. For accelerating or decelerating movements, the moving mass model may underestimate the deflections of the beam compared with the presented model; while for uniform motion, both the moving mass model and the moving mass-payload model lead to same beam responses. Furthermore, it is observed that the swing response of the payload is not sensitive to the stiffness of the beam for operational cases of a moving crane, thus a simple moving payload model can be employed in the swing control of the payload.

Cross-Cultural Perception of Spanish Synthetic Expressive Voices Among Asians

Directory of Open Access Journals (Sweden)

Ganapreeta Renunathan Naidu

2018-03-01

Full Text Available Nonverbal cues play a vital role in contributing to how emotions are perceived, especially by outgroups. In this study, a cross-cultural perception experiment of Spanish Synthetic Expressive Voices (SEV was conducted to investigate the perception rate among different groups of Asians towards the SEV. Ten (10 subjects from each ethnic group namely Japanese, Chinese, Vietnamese, and Malaysians participated in this test. The subjects were required to listen to and categorize the SEV corpus which contains 260 utterances with 4 emotions (anger, happiness, sadness, and surprise and the neutral speech in different intensities and durations. Overall, the results indicate that duration and intensity of speech plays a significant role in perception. This paper concludes that listeners’ perceptions are influenced by a speaker’s nonverbal expression and it is important that these features (duration and intensity of speech are considered when modelling synthetic speech for artificial agents in real-time applications in a cross-cultural user environment.

Expectation, information processing, and subjective duration.

Science.gov (United States)

Simchy-Gross, Rhimmon; Margulis, Elizabeth Hellmuth

2018-01-01

In research on psychological time, it is important to examine the subjective duration of entire stimulus sequences, such as those produced by music (Teki, Frontiers in Neuroscience, 10, 2016). Yet research on the temporal oddball illusion (according to which oddball stimuli seem longer than standard stimuli of the same duration) has examined only the subjective duration of single events contained within sequences, not the subjective duration of sequences themselves. Does the finding that oddballs seem longer than standards translate to entire sequences, such that entire sequences that contain oddballs seem longer than those that do not? Is this potential translation influenced by the mode of information processing-whether people are engaged in direct or indirect temporal processing? Two experiments aimed to answer both questions using different manipulations of information processing. In both experiments, musical sequences either did or did not contain oddballs (auditory sliding tones). To manipulate information processing, we varied the task (Experiment 1), the sequence event structure (Experiments 1 and 2), and the sequence familiarity (Experiment 2) independently within subjects. Overall, in both experiments, the sequences that contained oddballs seemed shorter than those that did not when people were engaged in direct temporal processing, but longer when people were engaged in indirect temporal processing. These findings support the dual-process contingency model of time estimation (Zakay, Attention, Perception & Psychophysics, 54, 656-664, 1993). Theoretical implications for attention-based and memory-based models of time estimation, the pacemaker accumulator and coding efficiency hypotheses of time perception, and dynamic attending theory are discussed.

Dynamics of thin-film piezoelectric microactuators with large vertical stroke subject to multi-axis coupling and fabrication asymmetries

Science.gov (United States)

Choi, Jongsoo; Wang, Thomas; Oldham, Kenn

2018-01-01

The high performance and small size of MEMS based scanners has allowed various optical imaging techniques to be realized in a small form factor. Many such devices are resonant scanners, and thus their linear and nonlinear dynamic behaviors have been studied in the past. Thin-film piezoelectric materials, in contrast, provide sufficient energy density to achieve both large static displacements and high-frequency resonance, but large deformation can in turn influence dynamic scanner behavior. This paper reports on the influence of very large stroke translation of a piezoelectric vertical actuator on its resonant behavior, which may not be otherwise explained fully by common causes of resonance shift such as beam stiffening or nonlinear forcing. To examine the change of structural compliance over the course of scanner motion, a model has been developed that includes internal forces from residual stress and the resultant additional multi-axis coupling among actuator leg structures. Like some preceding vertical scanning micro-actuators, the scanner of this work has four legs, with each leg featuring four serially connected thin-film PZT unimorphs that allow the scanner to generate larger than 400 µm of vertical displacement at 14 V DC. Using an excitation near one or more resonances, the input voltage can be lowered, and complementary multi-axis rotations can be also generated, but change of the resonant frequencies with scanner height needs to be understood to maximize scanner performance. The presented model well predicts the experimental observation of the decrease of the resonant frequencies of the scanner with the increase of a dc bias voltage. Also, the effects of the magnitude and uniformity of residual stress across the scanner structure on the natural frequencies have been studied.

Perception and eye movements in simulated traffic situations.

Science.gov (United States)

Luoma, J

1984-01-01

In an experiment to simulate the perception task of a driver, subjects were shown uninterrupted series of colour slides of different kinds of highway scenes. The dependent variables were eye fixations, fixation times and conscious perceptions for the part of the traffic signs and roadside advertisements. Perceptions were achieved mostly as a result of fixation, but partly also by using peripheral vision. On the other hand fixation did not always cause perception. The lengthening of fixation time increased the number of correct perceptions. When the traffic sign and the roadside advertisement were in the same slide, the advertisement disturbed the perception of the sign, but in the daylight conditions this effect was not noticed as an alteration of the fixation of the sign, but as prevention of further information processing. The disturbing influence of the advertisement was increased by its bad information ergonomics which caused a long fixation time.

Prosocial Behavior and Subjective Insecurity in Violent Contexts: Field Experiments

OpenAIRE

V?lez, Mar?a Alejandra; Trujillo, Carlos Andres; Moros, Lina; Forero, Clemente

2016-01-01

Subjective insecurity is a key determinant of different forms of prosocial behavior. In Study 1, we used field experiments with farmers in Colombian villages exposed to different levels of violence to investigate how individual perceptions of insecurity affect cooperation, trust, reciprocity and altruism. To do so, we developed a cognitive-affective measure of subjective insecurity. We found that subjective insecurity has a negative effect on cooperation but influences trust and altruism posi...

A novel vertical comb-drive electrostatic actuator using a one layer process

International Nuclear Information System (INIS)

Hailu, Zewdu; He, Siyuan; Mrad, Ridha Ben

2014-01-01

This paper presents the design, fabrication and testing of a new residual stress gradient based vertical comb-drive actuator. Conventional vertical comb-drive actuators need two structural layers, i.e. one for the moving fingers and a second for the fixed fingers. A vertical comb-drive actuator based on a single structural layer micromachining process, using the residual stress gradient along the thickness of the nickel of the MetalMUMPs (Metal Multi-User MEMS process) fabrication process, is developed. The MetalMUMPs provides a 20 μm thick nickel film and is subject to residual stress gradients along its thickness. Two curve-up beams are devised to curve out of plane after release. The curve-up beams raise a plate with comb fingers above the substrate to form the moving fingers. The fixed comb fingers are connected to the substrate via anchors. When a voltage is applied across the moving and the fixed fingers, the moving fingers move down towards the fixed fingers. Experimental measurements on prototypes have verified the design principle. A vertical displacement of 4.81 µm at 150 V was measured. (paper)

English Primary Trainee Teachers' Perceptions of Geography

Science.gov (United States)

Morley, Emma

2012-01-01

This paper summarises the findings of research conducted with one cohort of English undergraduate primary teacher trainees on point of entry to a 4-year course. The research examines the perceptions held of geography as a subject discipline and the purposes of teaching the subject. Two hundred and eleven trainees were asked to define geography and…

Perceptions on Multimedia technology by College of Education Teachers

Directory of Open Access Journals (Sweden)

Nachi Muthu

2012-08-01

Full Text Available Multimedia means, combination of text, audio, still images, animation, video and interactivity content forms delivered electronically. e-learning is a process and e-content is a product. The objectives of the study are to find out the significant relationship between the college of education teachers’ perception towards multimedia technology on the basis of gender wise, locality wise, maritial wise, subject wise, technical skill wise, experience wise and possessing degree wise. Evaluation of Multimedia Perception scale (EMPS developed by the investigator with a relaibility of 0.89 and it collected 350 teachers from Tamil Nadu State of Indian Context. From the analysis, there is no significant differences between the perceptions of multimedia technology in terms of gender, locality and maritial status. The same perception was rejected on the basis of  subject, technical skills, higher degree level and their experiences. The quality of learning depends not only on the form of how the process is carried out but also on what content is taught and how the content is presented.

Color differences and perceptive properties of prints made with microcapsules

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Raša Urbas

2015-06-01

Full Text Available The aim of the research was to establish whether addition on fragranced microcapsules influences on color values and perceptive properties of prints. For this purpose, three types of printing inks were used on two sets of the paper substrate. Color properties were measured by standard methods while perceptive properties were determined by subjective method. Research has shown that microcapsules cause small color differences while perceptive analyses gave very interesting results.

Psychology or semiotics: persons or subjects?

Science.gov (United States)

Bell, Philip

2005-01-01

Cultural studies and especially semiological theory has recently sought to re-conceptualise classical problems considered in academic psychology such as perception, identity, and "subjectivity". It is argued that these theorizations are reductionist and/or theoretically incoherent without an adequate epistemology. Yet they have become for many students of the human sciences the conventional modes of analyzing such questions as personal identity.

Physiotherapy Student Clinical Examinations: The Influence of Subjective Judgments on Observational Assessment.

Science.gov (United States)

Alexander, Helen A.

1996-01-01

A study investigated the role of subjective assessment in the evaluation of physiotherapy students in clinical programs. Clinical teachers, visiting lecturers, and students recorded perceptions of daily events and interactions in journals. Analysis suggests that assessors make subjective judgments about students that influence grades, and…

Probabilistic seismic hazard assessment for the effect of vertical ground motions on seismic response of highway bridges

Science.gov (United States)

Yilmaz, Zeynep

Typically, the vertical component of the ground motion is not considered explicitly in seismic design of bridges, but in some cases the vertical component can have a significant effect on the structural response. The key question of when the vertical component should be incorporated in design is answered by the probabilistic seismic hazard assessment study incorporating the probabilistic seismic demand models and ground motion models. Nonlinear simulation models with varying configurations of an existing bridge in California were considered in the analytical study. The simulation models were subjected to the set of selected ground motions in two stages: at first, only horizontal components of the motion were applied; while in the second stage the structures were subjected to both horizontal and vertical components applied simultaneously and the ground motions that produced the largest adverse effects on the bridge system were identified. Moment demand in the mid-span and at the support of the longitudinal girder and the axial force demand in the column are found to be significantly affected by the vertical excitations. These response parameters can be modeled using simple ground motion parameters such as horizontal spectral acceleration and vertical spectral acceleration within 5% to 30% error margin depending on the type of the parameter and the period of the structure. For a complete hazard assessment, both of these ground motion parameters explaining the structural behavior should also be modeled. For the horizontal spectral acceleration, Abrahamson and Silva (2008) model was used within many available standard model. A new NGA vertical ground motion model consistent with the horizontal model was constructed. These models are combined in a vector probabilistic seismic hazard analyses. Series of hazard curves developed and presented for different locations in Bay Area for soil site conditions to provide a roadmap for the prediction of these features for future

Adaptation of the vertical vestibulo-ocular reflex in cats during low-frequency vertical rotation.

Science.gov (United States)

Fushiki, Hiroaki; Maruyama, Motoyoshi; Shojaku, Hideo

2018-04-01

We examined plastic changes in the vestibulo-ocular reflex (VOR) during low-frequency vertical head rotation, a condition under which otolith inputs from the vestibular system are essential for VOR generation. For adaptive conditioning of the vertical VOR, 0.02Hz sinusoidal pitch rotation for one hour about the earth's horizontal axis was synchronized with out-of-phase vertical visual stimulation from a random dot pattern. A vertical VOR was well evoked when the upright animal rotated around the earth-horizontal axis (EHA) at low frequency due to the changing gravity stimulus and dynamic stimulation of the otoliths. After adaptive conditioning, the amplitude of the vertical VOR increased by an average of 32.1%. Our observations showing plasticity in the otolithic contribution to the VOR may provide a new strategy for visual-vestibular mismatch training in patients with otolithic disorders. This low-frequency vertical head rotation protocol also provides a model for investigating the mechanisms underlying the adaptation of VORs mediated by otolith activation. Copyright © 2017 Elsevier B.V. All rights reserved.

The Vertical Farm: A Review of Developments and Implications for the Vertical City

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Kheir Al-Kodmany

2018-02-01

Full Text Available This paper discusses the emerging need for vertical farms by examining issues related to food security, urban population growth, farmland shortages, “food miles”, and associated greenhouse gas (GHG emissions. Urban planners and agricultural leaders have argued that cities will need to produce food internally to respond to demand by increasing population and to avoid paralyzing congestion, harmful pollution, and unaffordable food prices. The paper examines urban agriculture as a solution to these problems by merging food production and consumption in one place, with the vertical farm being suitable for urban areas where available land is limited and expensive. Luckily, recent advances in greenhouse technologies such as hydroponics, aeroponics, and aquaponics have provided a promising future to the vertical farm concept. These high-tech systems represent a paradigm shift in farming and food production and offer suitable and efficient methods for city farming by minimizing maintenance and maximizing yield. Upon reviewing these technologies and examining project prototypes, we find that these efforts may plant the seeds for the realization of the vertical farm. The paper, however, closes by speculating about the consequences, advantages, and disadvantages of the vertical farm’s implementation. Economic feasibility, codes, regulations, and a lack of expertise remain major obstacles in the path to implementing the vertical farm.

The Influence Factors and Mechanism of Societal Risk Perception

Science.gov (United States)

Zheng, Rui; Shi, Kan; Li, Shu

Risk perception is one of important subjects in management psychology and cognitive psychology. It is of great value in the theory and practice to investigate the societal hazards that the public cares a lot especially in Socio-economic transition period. A survey including 30 hazards and 6 risk attributes was designed and distributed to about 2, 485 residents of 8 districts, Beijing. The major findings are listed as following: Firstly, a scale of societal risk perception was designed and 2 factors were identified (Dread Risk & Unknown Risk). Secondly, structural equation model was used to analyze the influence factors and mechanism of societal risk perception. Risk preference, government support and social justice could influence societal risk perception directly. Government support fully moderated the relationship between government trust and societal risk perception. Societal risk perception influenced life satisfaction, public policy preferences and social development belief.

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

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C. Christina

2017-06-01

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

Vertical pump assembly

International Nuclear Information System (INIS)

Dohnal, M.; Rosel, J.; Skarka, V.

1988-01-01

The mounting is described of the drive assembly of a vertical pump for nuclear power plants in areas with seismic risk. The assembly is attached to the building floor using flexible and damping elements. The design allows producing seismically resistant pumps without major design changes in the existing types of vertical pumps. (E.S.). 1 fig

Frequency of Gingival Display During Smiling and Comparison of Biometric Measurements in Subjects with and without Gingival Display

International Nuclear Information System (INIS)

Khan, F.; Abbas, M.

2014-01-01

Objective: To determine the frequency of gingival display during smiling and to compare biometric measurements in subjects with and without gingival display. Study Design: Cross-sectional study. Place and Duration of Study: Department of Prosthodontics, Dr. Ishrat-ul-Ibad Khan Institute of Oral Health Sciences, Dow University of Health Sciences, Karachi, from October 2012 to March 2013. Methodology: A total of 275 subjects (121 men and 154 women) were included in this study. The age of the participants ranged between 21 and 65 years. Measurements were carried out using digital caliper. For each participants, the gingival display was judged as either visible or not. The amounts of horizontal and vertical overlap of anterior teeth were measured using a digital caliper. Gender differences in these parameters and the relationship between subjects showing gingival display when smiling and the two intraoral dental biometric measurements were determined. Statistical analyses of data were performed using SPSS version 17.0 software. The mean scores for gender were calculated and a Student's t-test was used to identify significant differences between both groups. Significant level was set to 0.05. Results: A relatively small percentage of the subjects (37.8%) displayed gingiva when smiling. More women significantly displayed gingiva when smiling than men, with a 2:1 female: male ratio. Women had significantly (p=0.001) more horizontal overlap (3.34 +- 1.45 mm) than men (2.90 +- 1.44 mm), although no significant gender difference were found in vertical overlap. Subjects with gingival display had significantly (p < 0.05) more horizontal (3.49 +- 1.36 mm) and vertical (3.26 +- 1.47 mm) overlap of anterior teeth compared to those who did not display gingiva when smiling. Conclusion: Significantly more women displayed gingiva in smiling. Women had significantly more horizontal overlap than men. No gender differences were recorded between vertical overlap. Subjects who displayed

[Health education: perception of primary health care nurses in Uberaba, Minas Gerais State].

Science.gov (United States)

Cervera, Diana Patrícia Patino; Parreira, Bibiane Dias Miranda; Goulart, Bethania Ferreira

2011-01-01

Health education is a powerful tool that enhances social, economic and cultural contexts of the community, allied to the process of health promotion. The purpose of this study was to find the perception of nurses, related to the Family Health Strategy, on health education, in Uberaba, Minas Gerais State. It was a descriptive study, with a qualitative approach, using the method of thematic analysis. Semi-structured interviews were held with 20 nurses from Family Health Strategy (FHS) of that council. From the obtained information, five themes were abstracted: concepts; posture; bank education, professional growth; and occasional action. It was possible to identify that the subjects, in everyday life, have a wide perspective of health education, with a close relationship of professionals to this practice. However, workers still perceive this strategy in a vertical way, institutionalized, with a single-user sense of training. It is believed that this study could contribute to a discussion about the issue in practice, and thus enable the construction of a new look on health education, based on dialogical relations and the enhancement of popular knowledge.

Perception of parents as demonstrating the inherent merit of their values: relations with self-congruence and subjective well-being.

Science.gov (United States)

Yu, Shi; Assor, Avi; Liu, Xiangping

2015-02-01

This study focuses on the parenting practice of inherent value demonstration (IVD), involving parents' tendency to express their values in behaviours and appear satisfied and vital while doing so. Data from Chinese college students (n = 89) confirmed the hypothesis that offspring's perception of their parents as engaged in IVD predicts offspring's subjective well-being (SWB) through sense of self-congruence. Importantly, these relations emerged also when controlling for fundamental autonomy-supportive (FAS) parenting practices such as taking children's perspective, minimising control and allowing choice. These findings are consistent with the view that parents concerned with their children's sense of autonomy may do well to engage in IVD in addition to more fundamental autonomy-supportive practices. Future research may examine the role of IVD in promoting authentic values that serve as an internal compass that guides children to act in ways that feel self-congruent. © 2014 International Union of Psychological Science.

Vertical stability, high elongation, and the consequences of loss of vertical control on DIII-D

International Nuclear Information System (INIS)

Kellman, A.G.; Ferron, J.R.; Jensen, T.H.; Lao, L.L.; Luxon, J.L.; Skinner, D.G.; Strait, E.J.; Reis, E.; Taylor, T.S.; Turnbull, A.D.; Lazarus, E.A.; Lister, J.B.

1990-09-01

Recent modifications to the vertical control system for DIII-D has enabled operation of discharges with vertical elongation κ, up to 2.5. When vertical stability is lost, a disruption follows and a large vertical force on the vacuum vessel is observed. The loss of plasma energy begins when the edge safety factor q is 2 but the current decay does not begin until q ∼1.3. Current flow on the open field lines in the plasma scrapeoff layer has been measured and the magnitude and distribution of these currents can explain the observed force on the vessel. Equilibrium calculations and simulation of this vertical displacement episode are presented. 7 refs., 4 figs

Unsteady free convection MHD flow between two heated vertical parallel conducting plates

International Nuclear Information System (INIS)

Sanyal, D.C.; Adhikari, A.

2006-01-01

Unsteady free convection flow of a viscous incompressible electrically conducting fluid between two heated conducting vertical parallel plates subjected to a uniform transverse magnetic field is considered. The approximate analytical solutions for velocity, induced field and temperature distribution are obtained for small and large values of magnetic Reynolds number. The problem is also extended to thermometric case. (author)

Intra- and inter-subject variation in lower limb coordination during countermovement jumps in children and adults

DEFF Research Database (Denmark)

Raffalt, Peter C; Alkjær, Tine; Simonsen, Erik B

2016-01-01

-subject variability. Based on these results, it was concluded that the same movement solutions were available to both age groups, but the children were less able to consistently utilize the individually chosen coordination pattern. Thus, this ability appears to be developed through normal ontogenesis.......The purpose of the present study was to investigate the coordination pattern and coordination variability (intra-subject and inter-subject) in children and adults during vertical countermovement jumps. Ten children (mean age: 11.5±1.8years) and ten adults (mean age: 26.1±4.9years) participated...... in the experiment. Lower body 3D-kinematics and kinetics from both legs were obtained during 9 vertical jumps of each subject. Coordination pattern and coordination variability of intra-limb and inter-limb coupling were established by modified vector coding and continuous relative phase. The adult group jumped...

Self-motion perception: assessment by real-time computer-generated animations

Science.gov (United States)

Parker, D. E.; Phillips, J. O.

2001-01-01

We report a new procedure for assessing complex self-motion perception. In three experiments, subjects manipulated a 6 degree-of-freedom magnetic-field tracker which controlled the motion of a virtual avatar so that its motion corresponded to the subjects' perceived self-motion. The real-time animation created by this procedure was stored using a virtual video recorder for subsequent analysis. Combined real and illusory self-motion and vestibulo-ocular reflex eye movements were evoked by cross-coupled angular accelerations produced by roll and pitch head movements during passive yaw rotation in a chair. Contrary to previous reports, illusory self-motion did not correspond to expectations based on semicircular canal stimulation. Illusory pitch head-motion directions were as predicted for only 37% of trials; whereas, slow-phase eye movements were in the predicted direction for 98% of the trials. The real-time computer-generated animations procedure permits use of naive, untrained subjects who lack a vocabulary for reporting motion perception and is applicable to basic self-motion perception studies, evaluation of motion simulators, assessment of balance disorders and so on.

Running quietly reduces ground reaction force and vertical loading rate and alters foot strike technique.

Science.gov (United States)

Phan, Xuan; Grisbrook, Tiffany L; Wernli, Kevin; Stearne, Sarah M; Davey, Paul; Ng, Leo

2017-08-01

This study aimed to determine if a quantifiable relationship exists between the peak sound amplitude and peak vertical ground reaction force (vGRF) and vertical loading rate during running. It also investigated whether differences in peak sound amplitude, contact time, lower limb kinematics, kinetics and foot strike technique existed when participants were verbally instructed to run quietly compared to their normal running. A total of 26 males completed running trials for two sound conditions: normal running and quiet running. Simple linear regressions revealed no significant relationships between impact sound and peak vGRF in the normal and quiet conditions and vertical loading rate in the normal condition. t-Tests revealed significant within-subject decreases in peak sound, peak vGRF and vertical loading rate during the quiet compared to the normal running condition. During the normal running condition, 15.4% of participants utilised a non-rearfoot strike technique compared to 76.9% in the quiet condition, which was corroborated by an increased ankle plantarflexion angle at initial contact. This study demonstrated that quieter impact sound is not directly associated with a lower peak vGRF or vertical loading rate. However, given the instructions to run quietly, participants effectively reduced peak impact sound, peak vGRF and vertical loading rate.

Action-blindsight in healthy subjects after transcranial magnetic stimulation

DEFF Research Database (Denmark)

Christensen, Mark Schram; Kristiansen, Lasse; Rowe, James B.

2008-01-01

Clinical cases of blindsight have shown that visually guided movements can be accomplished without conscious visual perception. Here, we show that blindsight can be induced in healthy subjects by using transcranial magnetic stimulation over the visual cortex. Transcranial magnetic stimulation...

Do subjective symptoms predict our perception of jet-lag?

Science.gov (United States)

Waterhouse, J; Edwards, B; Nevill, A; Atkinson, G; Reilly, T; Davies, P; Godfrey, R

2000-10-01

A total of 39 subjects were studied after a flight from the UK to either Sydney or Brisbane (10 time-zones to the east). Subjects varied widely in their age, their athletic ability, whether or not they were taking melatonin, and in their objectives when in Australia. For the first 6 days after arrival, subjects scored their jet-lag five times per day and other subjective variables up to five times per day, using visual analogue scales. For jet-lag, the scale was labelled 0 = no jet-lag to 10 = very bad jet-lag; the extremes of the other scales were labelled - 5 and + 5, indicating marked changes compared with normal, and the centrepoint was labelled 0 indicating 'normal'. Mean daily values for jet-lag and fatigue were initially high (+ 3.65 +/- 0.35 and + 1.55 +/- 0.22 on day 1, respectively) and fell progressively on subsequent days, but were still raised significantly (p concentration and motivation, and rises in irritability and nocturnal wakings, had recovered by day 4 or earlier, and bowel activity was less frequent, with harder stools, on days 1 and 2 only. Also, on day 1, there was a decrease in the ease of getting to sleep (- 1.33 +/- 0.55), but this changed to an increase from day 2 onwards (for example, + 0.75 +/- 0.25 on day 6). Stepwise regression analysis was used to investigate predictors of jet-lag. The severity of jet-lag at all the times that were measured was strongly predicted by fatigue ratings made at the same time. Its severity at 08:00 h was predicted by an earlier time of waking, by feeling less alert 30 min after waking and, marginally, by the number of waking episodes. Jet-lag at 12:00 and 16:00 h was strongly predicted by a fall of concentration at these times; jet-lag at mealtimes (12:00, 16:00 and 20:00 h) was predicted by the amount of feeling bloated. Such results complicate an exact interpretation that can be placed on an assessment of a global term such as jet-lag, particularly if the assessment is made only once per day.

Public perception of nuclear installations

International Nuclear Information System (INIS)

Kiipper, Felipe de Moura

2011-01-01

The key for nuclear renaissance is public acceptance. Facing energetic needs that occur around the world and lack of resources, the work of characterizing and proposing new models to represent public opinion is extremely important to all stakeholders. Even though public opinion's study on risks is relatively recent, may approaches of this subject have been suggested and presented, especially for the topic of perceptions on nuclear installations. Actual definitions on risk exist between objective and subjective models, that reflect opinions of lay public and experts. Strategies on communications with the public may be evaluated from many developed models, and its results may be registered. The use of structural models may present an exploratory character as well as confirmatory theories, as an adequate tool for the development of studies on public perception. In this work, a structural model is presented from data obtained in a previous report, and added to data collected before and after the Fukushima nuclear accident, in Japan. The effects developed from this accident offered a unique opportunity to study public opinion through the effects of a serious nuclear accident and its effects on risk communications. Aside, this work attempted to check the structural model according with obtained results, in order to sustain a constant improvement of the working tools. Yet, a comparison between data according to experts' respondents and lay public ones as well as a comparison among different students before and after a visit to nuclear station is considered. Obtained data for the structural models has been applied for on a structural model and analyzed by structural correlation matrix, latent variable structural coefficients and R 2 values. Results indicate that public opinion maintains its rejection on nuclear energy and the perception of benefits, facing perceived risks before the accident, has diminished. A new model that included a latent variable for corresponding

Retrieving Vertical Air Motion and Raindrop Size Distributions from Vertically Pointing Doppler Radars

Science.gov (United States)

Williams, C. R.; Chandra, C. V.

2017-12-01

The vertical evolution of falling raindrops is a result of evaporation, breakup, and coalescence acting upon those raindrops. Computing these processes using vertically pointing radar observations is a two-step process. First, the raindrop size distribution (DSD) and vertical air motion need to be estimated throughout the rain shaft. Then, the changes in DSD properties need to be quantified as a function of height. The change in liquid water content is a measure of evaporation, and the change in raindrop number concentration and size are indicators of net breakup or coalescence in the vertical column. The DSD and air motion can be retrieved using observations from two vertically pointing radars operating side-by-side and at two different wavelengths. While both radars are observing the same raindrop distribution, they measure different reflectivity and radial velocities due to Rayleigh and Mie scattering properties. As long as raindrops with diameters greater than approximately 2 mm are in the radar pulse volumes, the Rayleigh and Mie scattering signatures are unique enough to estimate DSD parameters using radars operating at 3- and 35-GHz (Williams et al. 2016). Vertical decomposition diagrams (Williams 2016) are used to explore the processes acting on the raindrops. Specifically, changes in liquid water content with height quantify evaporation or accretion. When the raindrops are not evaporating, net raindrop breakup and coalescence are identified by changes in the total number of raindrops and changes in the DSD effective shape as the raindrops. This presentation will focus on describing the DSD and air motion retrieval method using vertical profiling radar observations from the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) central facility in Northern Oklahoma.

Trade Liberalisation and Vertical Integration

DEFF Research Database (Denmark)

Bache, Peter Arendorf; Laugesen, Anders

We build a three-country model of international trade in final goods and intermediate inputs and study the relation between different types of trade liberalisation and vertical integration. Firms are heterogeneous with respect to both productivity and factor intensity as observed in data. Final......-good producers face decisions on exporting, vertical integration of intermediate-input production, and whether the intermediate-input production should be offshored to a low-wage country. We find that the fractions of final-good producers that pursue either vertical integration, offshoring, or exporting are all...... increasing when intermediate-input or final-goods trade is liberalised and when the fixed cost of vertical integration is reduced. At the same time, one observes firms that shift away from either vertical integration, offshoring, or exporting. Further, we provide guidance for testing the open...

Subjective Well-Being and Life Satisfaction in the Kingdom of Tonga

Science.gov (United States)

Moore, Sean E.; Leslie, Heather Young; Lavis, Carrie A.

2005-01-01

This paper describes an initial attempt to assess the subjective well-being of a sample of 227 Tongans via self-report. Using items adapted from the Subjective Well Being Inventory (SUBI; Nagpal and Sell, 1985; Sell and Nagpal, 1992), participants rated their level of overall life satisfaction along with their perceptions of well-being in a number…

Cognitive style as a factor in accounting students' perceptions of career-choice factors.

Science.gov (United States)

Gul, F; Huang, A; Subramaniam, N

1992-12-01

Since prior studies of individuals' perceptions of career-choice factors have not considered the effect of cognitive styles of subjects, this study, using 68 accounting students, investigated the mediating effects of the field dependent-independent cognitive dimension on perceptions of the importance of career-choice factors. The results, in general, show that cognitive style affected individuals' perceptions of career-choice factors, suggesting that future studies of individuals' perceptions should take into account individual cognitive differences.

Vertical distribution of alewife in the Lake Ontario offshore: Implications for resource use

Czech Academy of Sciences Publication Activity Database

Říha, Milan; Walsh, M. G.; Connerton, M. J.; Holden, J.; Weidel, B. C.; Sullivan, P. J.; Holda, T. J.; Rudstam, L. G.

2017-01-01

Roč. 43, č. 5 (2017), s. 823-837 ISSN 0380-1330 R&D Projects: GA MŠk(CZ) LD15021 Institutional support: RVO:60077344 Keywords : diel vertical migration * deep chlorophyll layer * zooplankton * mysids * alewife Subject RIV: DA - Hydrology ; Limnology OBOR OECD: Marine biology, freshwater biology, limnology Impact factor: 1.958, year: 2016

Self-perception of ethical behaviour. The case of listed Spanish companies

OpenAIRE

García López, María José; Amat, Oriol

2015-01-01

In recent years there has been much talk about the ethics of organisations and studies on the subject are plentiful. However, there has been scarcely any research into the perception that companies themselves have of their ethical behaviour. This article presents the results showing the self-perception that listed Spanish companies have of their ethical behaviour, with the observation that, generally, they have a greater perception than the reality of the study actually shows.

Risk perception of obesity and bariatric surgery in patients seeking treatment for obesity.

Science.gov (United States)

Prasad, Chaithra; Batsis, John A; Lopez-Jimenez, Francisco; Clark, Matthew M; Somers, Virend K; Sarr, Michael G; Collazo-Clavell, Maria L

2014-06-01

Bariatric surgery (BSx) produces clinically relevant weight loss that translates into improved quality of life, decreased mortality, and reduction in medical comorbidities, including cardiovascular (CV) risk. Little is known about patients' decision-making process to undergo BSx, but risk perception is known to influence medical decision-making. This study examined CV and BSx risk perception in obese subjects undergoing BSx (n = 268) versus those managed medically (MM) (n = 273). This retrospective population-based survey of subjects evaluated for BSx had 148 (55%) and 88 (32%) responders in the BSx and MM groups, respectively. Survey questions assessed risk perceptions and habits prior to weight loss intervention. CV risk was calculated using the Framingham Risk Score (FRS). At baseline, BSx subjects had a greater body mass index and greater prevalence of diabetes and depression. Follow-up mean weight loss was greater in the BSx group. BSx subjects perceived obesity as a greater risk to their overall health than the surgical risk. FRS declined in the BSx group (10 to 5%; p risk had a greater tendency to perceive the risk of BSx as greater than that of obesity. Obese subjects undergoing BSx are more likely than MM subjects to perceive obesity as a greater risk to their health than BSx. MM subjects generally underestimate their CV risk and overestimate the risk of BSx. Active discussion of CV risk using the FRS and the perception of risk associated with bariatric surgery can enhance patients' ability to make an informed decision regarding their management. © The European Society of Cardiology 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Antihysteresis of perceived longitudinal body axis during continuous quasi-static whole-body rotation in the earth-vertical roll plane.

Science.gov (United States)

Tatalias, M; Bockisch, C J; Bertolini, G; Straumann, D; Palla, A

2011-03-01

Estimation of subjective whole-body tilt in stationary roll positions after rapid rotations shows hysteresis. We asked whether this phenomenon is also present during continuous quasi-static whole-body rotation and whether gravitational cues are a major contributing factor. Using a motorized turntable, 8 healthy subjects were rotated continuously about the earth-horizontal naso-occipital axis (earth-vertical roll plane) and the earth-vertical naso-occipital axis (earth-horizontal roll plane). In both planes, three full constant velocity rotations (2°/s) were completed in clockwise and counterclockwise directions (acceleration = 0.05°/s(2), velocity plateau reached after 40 s). Subjects adjusted a visual line along the perceived longitudinal body axis (pLBA) every 2 s. pLBA deviation from the longitudinal body axis was plotted as a function of whole-body roll position, and a sine function was fitted. At identical whole-body earth-vertical roll plane positions, pLBA differed depending on whether the position was reached by a rotation from upright or by passing through upside down. After the first 360° rotation, pLBA at upright whole-body position deviated significantly in the direction of rotation relative to pLBA prior to rotation initiation. This deviation remained unchanged after subsequent full rotations. In contrast, earth-horizontal roll plane rotations resulted in similar pLBA before and after each rotation cycle. We conclude that the deviation of pLBA in the direction of rotation during quasi-static earth-vertical roll plane rotations reflects static antihysteresis and might be a consequence of the known static hysteresis of ocular counterroll: a visual line that is perceived that earth-vertical is expected to be antihysteretic, if ocular torsion is hysteretic.

Speech perception performance of subjects with type I diabetes mellitus in noise

Directory of Open Access Journals (Sweden)

Bárbara Cristiane Sordi Silva

Full Text Available Abstract Introduction: Diabetes mellitus (DM is a chronic metabolic disorder of various origins that occurs when the pancreas fails to produce insulin in sufficient quantities or when the organism fails to respond to this hormone in an efficient manner. Objective: To evaluate the speech recognition in subjects with type I diabetes mellitus (DMI in quiet and in competitive noise. Methods: It was a descriptive, observational and cross-section study. We included 40 participants of both genders aged 18-30 years, divided into a control group (CG of 20 healthy subjects with no complaints or auditory changes, paired for age and gender with the study group, consisting of 20 subjects with a diagnosis of DMI. First, we applied basic audiological evaluations (pure tone audiometry, speech audiometry and immittance audiometry for all subjects; after these evaluations, we applied Sentence Recognition Threshold in Quiet (SRTQ and Sentence Recognition Threshold in Noise (SRTN in free field, using the List of Sentences in Portuguese test. Results: All subjects showed normal bilateral pure tone threshold, compatible speech audiometry and "A" tympanometry curve. Group comparison revealed a statistically significant difference for SRTQ (p = 0.0001, SRTN (p < 0.0001 and the signal-to-noise ratio (p < 0.0001. Conclusion: The performance of DMI subjects in SRTQ and SRTN was worse compared to the subjects without diabetes.

Prediction of vertical jump height from anthropometric factors in male and female martial arts athletes.

Science.gov (United States)

Abidin, Nahdiya Zainal; Adam, Mohd Bakri

2013-01-01

Vertical jump is an index representing leg/kick power. The explosive movement of the kick is the key to scoring in martial arts competitions. It is important to determine factors that influence the vertical jump to help athletes improve their leg power. The objective of the present study is to identify anthropometric factors that influence vertical jump height for male and female martial arts athletes. Twenty-nine male and 25 female athletes participated in this study. Participants were Malaysian undergraduate students whose ages ranged from 18 to 24 years old. Their heights were measured using a stadiometer. The subjects were weighted using digital scale. Body mass index was calculated by kg/m(2). Waist-hip ratio was measured from the ratio of waist to hip circumferences. Body fat % was obtained from the sum of four skinfold thickness using Harpenden callipers. The highest vertical jump from a stationary standing position was recorded. The maximum grip was recorded using a dynamometer. For standing back strength, the maximum pull upwards using a handle bar was recorded. Multiple linear regression was used to obtain the relationship between vertical jump height and explanatory variables with gender effect. Body fat % has a significant negative relationship with vertical jump height (P martial arts athletes can be predicted by body fat %. The vertical jump for male is higher than for their female counterparts. Reducing body fat by proper dietary planning will help to improve leg power.

The Apple Phenomenon: the Impact of Modern Technologies on Subject

OpenAIRE

Kuldová, Michaela

2013-01-01

The Apple Phenomenon: the Impact of Modern Technologies on Subject Abstract The goal of the submitted thesis is the study of the company Apple Inc. in the context of how it is percieved by subjects. After a brief introduction of the company Apple Inc. we will focus on semiotic analysis of the brand Apple, its products and marketing strategies. The object of study will be also a present society, whose distinguishing feature is a consumption, and brand perception of a subject in connection with...

The influence of vertical disparity gradient and cue conflict on EEG omega complexity in Panum's limiting case.

Science.gov (United States)

Li, Huayun; Jia, Huibin; Yu, Dongchuan

2018-03-01

Using behavioral measures and ERP technique, researchers discovered at least two factors could influence the final perception of depth in Panum's limiting case, which are the vertical disparity gradient and the degree of cue conflict between two- and three-dimensional shapes. Although certain event-related potential components have been proved to be sensitive to the different levels of these two factors, some methodological limitations existed in this technique. In this study, we proposed that the omega complexity of EEG signal may serve as an important supplement of the traditional event-related potential technique. We found that the trials with lower vertical gradient disparity have lower omega complexity (i.e., higher global functional connectivity) of the occipital region, especially that of the right-occipital hemisphere. Moreover, for occipital omega complexity, the trials with low-cue conflict have significantly larger omega complexity than those with medium- and high-cue conflict. It is also found that the electrodes located in the middle line of the occipital region (i.e., POz and Oz) are more crucial to the impact of different levels of cue conflict on omega complexity than the other electrodes located in the left- and right-occipital hemispheres. These evidences demonstrated that the EEG omega complexity could reflect distinct neural activities evoked by Panum's limiting case configurations, with different levels of vertical disparity gradient and cue conflict. Besides, the influence of vertical disparity gradient and cue conflict on omega complexity may be regional dependent. NEW & NOTEWORTHY The EEG omega complexity could reflect distinct neural activities evoked by Panum's limiting case configurations with different levels of vertical disparity gradient and cue conflict. The influence of vertical disparity gradient and cue conflict on omega complexity is regional dependent. The omega complexity of EEG signal can serve as an important supplement of the

Perception of male drinkers as a function of their alcoholic beverage preference.

Science.gov (United States)

Curtin, L; Fisher, R D

1993-05-01

The present study examined perception of a man's likelihood of driving after drinking and his ability to do so as a function of his choice of beverage. Perceptions of his social characteristics were also examined. The sample was composed of 200 volunteer undergraduate psychology students. Equal numbers of male and female subjects read one of four vignettes which varied only in the male protagonist's choice of beverage: beer, wine, shots of distilled spirits, or cola. After reading the story, subjects answered multiple-choice questions about the character, tapping social judgments, situational judgments and drinking and driving judgments. Subject drinking habits were also assessed. The most notable result was the consistently positive perception of the protagonist portrayed as an abstainer. The lack of a consistent alcoholic beverage distinction implies that the beer-spirits double standard is far from a clear-cut discrimination. Possible explanations for results are discussed. This study questions the robustness of the alcoholic beverage type bias and reflects the need for future research.

The feeling of fluent perception: a single experience from multiple asynchronous sources.

Science.gov (United States)

Wurtz, Pascal; Reber, Rolf; Zimmermann, Thomas D

2008-03-01

Zeki and co-workers recently proposed that perception can best be described as locally distributed, asynchronous processes that each create a kind of microconsciousness, which condense into an experienced percept. The present article is aimed at extending this theory to metacognitive feelings. We present evidence that perceptual fluency-the subjective feeling of ease during perceptual processing-is based on speed of processing at different stages of the perceptual process. Specifically, detection of briefly presented stimuli was influenced by figure-ground contrast, but not by symmetry (Experiment 1) or the font (Experiment 2) of the stimuli. Conversely, discrimination of these stimuli was influenced by whether they were symmetric (Experiment 1) and by the font they were presented in (Experiment 2), but not by figure-ground contrast. Both tasks however were related with the subjective experience of fluency (Experiments 1 and 2). We conclude that subjective fluency is the conscious phenomenal correlate of different processing stages in visual perception.

A mental models approach to exploring perceptions of hazardous processes

International Nuclear Information System (INIS)

Bostrom, A.H.H.

1990-01-01

Based on mental models theory, a decision-analytic methodology is developed to elicit and represent perceptions of hazardous processes. An application to indoor radon illustrates the methodology. Open-ended interviews were used to elicit non-experts' perceptions of indoor radon, with explicit prompts for knowledge about health effects, exposure processes, and mitigation. Subjects then sorted photographs into radon-related and unrelated piles, explaining their rationale aloud as they sorted. Subjects demonstrated a small body of correct but often unspecific knowledge about exposure and effects processes. Most did not mention radon-decay processes, and seemed to rely on general knowledge about gases, radioactivity, or pollution to make inferences about radon. Some held misconceptions about contamination and health effects resulting from exposure to radon. In two experiments, subjects reading brochures designed according to the author's guidelines outperformed subjects reading a brochure distributed by the EPA on a diagnostic test, and did at least as well on an independently designed quiz. In both experiments, subjects who read any one of the brochures had more complete and correct knowledge about indoor radon than subjects who did not, whose knowledge resembled the radon-interview subjects'

Vertical grid of retrieved atmospheric profiles

International Nuclear Information System (INIS)

Ceccherini, Simone; Carli, Bruno; Raspollini, Piera

2016-01-01

The choice of the vertical grid of atmospheric profiles retrieved from remote sensing observations is discussed considering the two cases of profiles used to represent the results of individual measurements and of profiles used for subsequent data fusion applications. An ozone measurement of the MIPAS instrument is used to assess, for different vertical grids, the quality of the retrieved profiles in terms of profile values, retrieval errors, vertical resolutions and number of degrees of freedom. In the case of individual retrievals no evident advantage is obtained with the use of a grid finer than the one with a reduced number of grid points, which are optimized according to the information content of the observations. Nevertheless, this instrument dependent vertical grid, which seems to extract all the available information, provides very poor results when used for data fusion applications. A loss of about a quarter of the degrees of freedom is observed when the data fusion is made using the instrument dependent vertical grid relative to the data fusion made using a vertical grid optimized for the data fusion product. This result is explained by the analysis of the eigenvalues of the Fisher information matrix and leads to the conclusion that different vertical grids must be adopted when data fusion is the expected application. - Highlights: • Data fusion application is taken into account for the choice of the vertical grid. • The study is performed using ozone profiles retrieved from MIPAS measurements. • A very fine vertical grid is not needed for the analysis of a single instrument. • The instrument dependent vertical grid is not the best choice for data fusion. • A data fusion dependent vertical grid must be used for profiles that will be fused.

[Differential aspects of subjective burden of tinnitus aurium].

Science.gov (United States)

Perrig-Chiello, P; Gusset, S

1996-01-01

This study focuses on psychological variables, which could influence the subjectively perceived strain of tinnitus. They concern personality traits such as self-attentiveness, control beliefs and different dimensions of psychological health. Two groups of tinnitus patients were compared, one with low subjectively perceived strain (n = 20), the other with high subjectively perceived strain (n = 30). Results reveal that people with high subjectively perceived strain do not only perceive their tinnitus more often, but they are more self-centered and report significantly more general somatic complaints than people with low subjectively perceived strain. They obviously pay more attention to themselves and as a consequence also to their tinnitus. However, we didn't find any relationship between control beliefs and subjectively perceived tinnitus strain. Furthermore, duration of the noises, their loudness, their localisation and the knowledge of the cause of tinnitus also seem to affect the perception of the noises.

Tip displacement variance of manipulator to simultaneous horizontal and vertical stochastic base excitations

International Nuclear Information System (INIS)

Rahi, A.; Bahrami, M.; Rastegar, J.

2002-01-01

The tip displacement variance of an articulated robotic manipulator to simultaneous horizontal and vertical stochastic base excitation is studied. The dynamic equations for an n-links manipulator subjected to both horizontal and vertical stochastic excitations are derived by Lagrangian method and decoupled for small displacement of joints. The dynamic response covariance of the manipulator links is computed in the coordinate frame attached to the base and then the principal variance of tip displacement is determined. Finally, simulation for a two-link planner robotic manipulator under base excitation is developed. Then sensitivity of the principal variance of tip displacement and tip velocity to manipulator configuration, damping, excitation parameters and manipulator links length are investigated

International competition in vertically differentiated markets with innovation and imitation: trade policy versus free trade

Czech Academy of Sciences Publication Activity Database

Kováč, E.; Žigić, Krešimir

-, č. 336 (2007), s. 1-51 ISSN 1211-3298 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:MSM0021620846 Keywords : vertical differentiation * free trade * strategic trade policy Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp336.pdf

Changes in gallbladder bile composition and crystal detection time in morbidly obese subjects after bariatric surgery

NARCIS (Netherlands)

Gustafsson, Ulf; Benthin, Lisbet; Granström, Lars; Groen, Albert K.; Sahlin, Staffan; Einarsson, Curt

2005-01-01

The aim of the present study was to elucidate the mechanisms of development of cholesterol crystals and gallstones during weight reduction in obese subjects. Twenty-five morbidly obese, gallstone-free subjects underwent vertical-banded gastroplasty. Gallbladder bile was collected at the time of the

Public risk perception of food additives and food scares. The case in Suzhou, China.

Science.gov (United States)

Wu, Linhai; Zhong, Yingqi; Shan, Lijie; Qin, Wei

2013-11-01

This study examined the factors affecting public risk perception of food additive safety and possible resulting food scares using a survey conducted in Suzhou, Jiangsu Province, China. The model was proposed based on literature relating to the role of risk perception and information perception of public purchase intention under food scares. Structural equation modeling (SEM) was used for data analysis. The results showed that attitude towards behavior, subjective norm and information perception exerted moderate to high effect on food scares, and the effects were also mediated by risk perceptions of additive safety. Significant covariance was observed between attitudes toward behavior, subjective norm and information perception. Establishing an effective mechanism of food safety risk communication, releasing information of government supervision on food safety in a timely manner, curbing misleading media reports on public food safety risk, and enhancing public knowledge of the food additives are key to the development and implementation of food safety risk management policies by the Chinese government. Copyright © 2013 Elsevier Ltd. All rights reserved.

Autonomic nervous system responses during perception of masked speech may reflect constructs other than subjective listening effort

Directory of Open Access Journals (Sweden)

Alexander L. Francis

2016-03-01

Full Text Available Typically, understanding speech seems effortless and automatic. However, a variety of factors may, independently or interactively, make listening more effortful. Physiological measures may help to distinguish between the application of different cognitive mechanisms whose operation is perceived as effortful. In the present study, physiological and behavioral measures associated with task demand were collected along with behavioral measures of performance while participants listened to and repeated sentences. The goal was to measure psychophysiological reactivity associated with three degraded listening conditions, each of which differed in terms of the source of the difficulty (distortion, energetic masking, and informational masking, and therefore were expected to engage different cognitive mechanisms. These conditions were chosen to be matched for overall performance (keywords correct, and were compared to listening to unmasked speech produced by a natural voice. The three degraded conditions were: (1 Unmasked speech produced by a computer speech synthesizer, (2 Speech produced by a natural voice and masked by speech-shaped noise and (3 Speech produced by a natural voice and masked by two-talker babble. Masked conditions were both presented at a -8 dB signal to noise ratio (SNR, a level shown in previous research to result in comparable levels of performance for these stimuli and maskers. Performance was measured in terms of proportion of key words identified correctly, and task demand or effort was quantified subjectively by self-report. Measures of psychophysiological reactivity included electrodermal (skin conductance response frequency and amplitude, blood pulse amplitude and pulse rate. Results suggest that the two masked conditions evoked stronger psychophysiological reactivity than did the two unmasked conditions even when behavioral measures of listening performance and listeners’ subjective perception of task demand were comparable

Bridging consciousness and cognition in memory and perception: evidence for both state and strength processes.

Science.gov (United States)

Aly, Mariam; Yonelinas, Andrew P

2012-01-01

Subjective experience indicates that mental states are discrete, in the sense that memories and perceptions readily come to mind in some cases, but are entirely unavailable to awareness in others. However, a long history of psychophysical research has indicated that the discrete nature of mental states is largely epiphenomenal and that mental processes vary continuously in strength. We used a novel combination of behavioral methodologies to examine the processes underlying perception of complex images: (1) analysis of receiver operating characteristics (ROCs), (2) a modification of the change-detection flicker paradigm, and (3) subjective reports of conscious experience. These methods yielded converging results showing that perceptual judgments reflect the combined, yet functionally independent, contributions of two processes available to conscious experience: a state process of conscious perception and a strength process of knowing; processes that correspond to recollection and familiarity in long-term memory. In addition, insights from the perception experiments led to the discovery of a new recollection phenomenon in a long-term memory change detection paradigm. The apparent incompatibility between subjective experience and theories of cognition can be understood within a unified state-strength framework that links consciousness to cognition across the domains of perception and memory.

Students Performance And Perception Of Neurophysiology ...

African Journals Online (AJOL)

We also surveyed learning experience of a batch of graduating doctors in neurosciences (n=50) and surveyed the staff and students' perception of the teaching of neurophysiology. The students performances in neurophysiology was comparatively poorer than in cardiovascular and endocrinology aspects of the subject over ...

Coexistence of Strategic Vertical Separation and Integration

DEFF Research Database (Denmark)

Jansen, Jos

2003-01-01

This paper gives conditions under which vertical separation is chosen by some upstream firms, while vertical integration is chosen by others in the equilibrium of a symmetric model. A vertically separating firm trades off fixed contracting costs against the strategic benefit of writing a (two......-part tariff, exclusive dealing) contract with its retailer. Coexistence emerges when more than two vertical Cournot oligopolists supply close substitutes. When vertical integration and separation coexist, welfare could be improved by reducing the number of vertically separating firms. The scope...

Integration of auditory and tactile inputs in musical meter perception.

Science.gov (United States)

Huang, Juan; Gamble, Darik; Sarnlertsophon, Kristine; Wang, Xiaoqin; Hsiao, Steven

2013-01-01

Musicians often say that they not only hear but also "feel" music. To explore the contribution of tactile information to "feeling" music, we investigated the degree that auditory and tactile inputs are integrated in humans performing a musical meter-recognition task. Subjects discriminated between two types of sequences, "duple" (march-like rhythms) and "triple" (waltz-like rhythms), presented in three conditions: (1) unimodal inputs (auditory or tactile alone); (2) various combinations of bimodal inputs, where sequences were distributed between the auditory and tactile channels such that a single channel did not produce coherent meter percepts; and (3) bimodal inputs where the two channels contained congruent or incongruent meter cues. We first show that meter is perceived similarly well (70-85 %) when tactile or auditory cues are presented alone. We next show in the bimodal experiments that auditory and tactile cues are integrated to produce coherent meter percepts. Performance is high (70-90 %) when all of the metrically important notes are assigned to one channel and is reduced to 60 % when half of these notes are assigned to one channel. When the important notes are presented simultaneously to both channels, congruent cues enhance meter recognition (90 %). Performance dropped dramatically when subjects were presented with incongruent auditory cues (10 %), as opposed to incongruent tactile cues (60 %), demonstrating that auditory input dominates meter perception. These observations support the notion that meter perception is a cross-modal percept with tactile inputs underlying the perception of "feeling" music.

Influence of a sport-specific training background on vertical jumping and throwing performance in young female basketball and volleyball players.

Science.gov (United States)

Battaglia, G; Paoli, A; Bellafiore, M; Bianco, A; Palma, A

2014-10-01

The purpose of this study was to evaluate the influence of 3 years of sport-specific training background (SSTB) on vertical jumping and throwing performance in young female basketball and volleyball players. Thirty-one healthy adolescent girls, of which 11 age-matched control subjects [C], 10 basketballers (BP) and 10 volleyballers (VP) participated to the study. The throwing performance was assessed by seated backward overhead ball throw (SBOMBT) and seated chest pass throw (SCPT) using a 3-kg rubber medicine ball. Instead, the vertical jumping performance was evaluated by squat jump (SJ) and countermovement jump with (CMJ-AS) and without arm swing (CMJ) using Optojump system (Microgate srl, Italy). During SJ and CMJ with and without arm swing VP group showed a higher vertical jump performance than BP and C ones. In particular we showed that VP exhibited a higher flight time and jump height than C (Pbasketball athletes' maximal power compared to age-matched control subjects.

Echoic memory and language perception.

Science.gov (United States)

Ardila, A; Montanes, P; Gempeler, J

1986-09-01

The purpose of this study was to analyze asymmetry in echoic memory as a relevant factor in language perception. Two experimental procedures were used: the presentation of temporally segmented words in fragments of 40, 80, 120 and 240 msec, separated by intervals of 40, 80, 120 and 240 msec, similar to the procedures used by A. W. F. Huggins (1975, Perception & Psychophysics, 18, 149-157); the presentation of two tones of short duration, "high" and "low," followed by an interference tone equivalent to the mean frequency of the two tones, closely following the procedure used by D. W. Massaro (1975, in D.W. Massaro (Ed.), Understanding language, New York: Academic Press). A stereophonic tape recorder was used as follows: one channel was employed for the presentation of the words or tones while, through the other channel, the subject received a white noise equivalent in intensity. All subjects carried out the task twice (right ear, left ear) and the order of presentation was counterbalanced. Only the first task showed differences between ears. Implications of the results are analyzed.

Perception of the Body in Space: Mechanisms

Science.gov (United States)

Young, Laurence R.

1991-01-01

The principal topic is the perception of body orientation and motion in space and the extent to which these perceptual abstraction can be related directly to the knowledge of sensory mechanisms, particularly for the vestibular apparatus. Spatial orientation is firmly based on the underlying sensory mechanisms and their central integration. For some of the simplest situations, like rotation about a vertical axis in darkness, the dynamic response of the semicircular canals furnishes almost enough information to explain the sensations of turning and stopping. For more complex conditions involving multiple sensory systems and possible conflicts among their messages, a mechanistic response requires significant speculative assumptions. The models that exist for multisensory spatial orientation are still largely of the non-rational parameter variety. They are capable of predicting relationships among input motions and output perceptions of motion, but they involve computational functions that do not now and perhaps never will have their counterpart in central nervous system machinery. The challenge continues to be in the iterative process of testing models by experiment, correcting them where necessary, and testing them again.

Association between swallow perception and esophageal bolus clearance in patients with globus sensation.

Science.gov (United States)

Chen, Chien-Lin; Yi, Chih-Hsun; Liu, Tso-Tsai

2013-04-01

Globus sensation is common, but its pathogenesis is not yet clear. Our purpose was to investigate subjective perception of swallowing and esophageal motility by combined multichannel intraluminal impedance and manometry (MII-EM) for patients with globus sensation. Combined MII-EM was performed for 25 globus patients and 15 healthy controls. Swallows were abnormal if hypocontractivity or simultaneous contractions occurred. Esophageal bolus transit was incomplete if bolus exit was not found at one or more of all measurement sites. Perception of each swallow was assessed by use of a standardized scoring system, and was enhanced if the score was >1. Few globus patients reported enhanced perception during viscous or solid swallows. Incomplete bolus transit and enhanced perception occurred similarly between viscous and solid boluses. Agreement between enhanced perception and proximal bolus clearance was greater during solid swallows (κ = 0.45, 95 % CI: 0.32-0.58) than during viscous swallows (κ = 0.13, 95 % CI: 0-0.25) (P perception and total bolus clearance was greater during solid swallows (κ = 0.46, 95 % CI: 0.34-0.58) than during viscous swallows (κ = 0.11, 95 % CI: 0-0.22) (P perception is uncommon in patients with globus sensation, although there is a significant association between enhanced esophageal perception and solid bolus clearance. Application of a solid bolus may help better delineation of the interrelationship between the subjective perception of bolus passage and the objective measurement of bolus clearance.

The Reduction of Vertical Interchannel Crosstalk: The Analysis of Localisation Thresholds for Natural Sound Sources

Directory of Open Access Journals (Sweden)

Rory Wallis

2017-03-01

Full Text Available In subjective listening tests, natural sound sources were presented to subjects as vertically-oriented phantom images from two layers of loudspeakers, ‘height’ and ‘main’. Subjects were required to reduce the amplitude of the height layer until the position of the resultant sound source matched that of the same source presented from the main layer only (the localisation threshold. Delays of 0, 1 and 10 ms were applied to the height layer with respect to the main, with vertical stereophonic and quadraphonic conditions being tested. The results of the study showed that the localisation thresholds obtained were not significantly affected by sound source or presentation method. Instead, the only variable whose effect was significant was interchannel time difference (ICTD. For ICTD of 0 ms, the median threshold was −9.5 dB, which was significantly lower than the −7 dB found for both 1 and 10 ms. The results of the study have implications both for the recording of sound sources for three-dimensional (3D audio reproduction formats and also for the rendering of 3D images.

COMPUTING VERTICES OF INTEGER PARTITION POLYTOPES

Directory of Open Access Journals (Sweden)

A. S. Vroublevski

2015-01-01

Full Text Available The paper describes a method of generating vertices of the polytopes of integer partitions that was used by the authors to calculate all vertices and support vertices of the partition polytopes for all n ≤ 105 and all knapsack partitions of n ≤ 165. The method avoids generating all partitions of n. The vertices are determined with the help of sufficient and necessary conditions; in the hard cases, the well-known program Polymake is used. Some computational aspects are exposed in more detail. These are the algorithm for checking the criterion that characterizes partitions that are convex combinations of two other partitions; the way of using two combinatorial operations that transform the known vertices to the new ones; and employing the Polymake to recognize a limited number (for small n of partitions that need three or more other partitions for being convexly expressed. We discuss the computational results on the numbers of vertices and support vertices of the partition polytopes and some appealing problems these results give rise to.

Measurement of vertical bar Vub vertical bar in semi-inclusive charmless B → πX decays

International Nuclear Information System (INIS)

Kim, C.S.; Lee, Jake; Oha, Sechul

2002-01-01

We study semi-inclusive charmless decays B → πX, where X does not contain a charm (anti)quark. The mode B-bar 0 → π - X turns out to be be particularly useful for determination of the CKM matrix element vertical bar V ub vertical bar. We present the branching ratio (BR) of B-bar 0 → π - X as a function of vertical bar V ub vertical bar, with an estimation of possible uncertainty. The BR is expected to be an order of 10 -4

Students’ Perceptions on a Good Tertiary Foreign Language Teacher

Directory of Open Access Journals (Sweden)

Siti Tarwiyah

2013-11-01

Full Text Available This paper investigates students’ perception of tertiary teachers’ attitude, method of teaching and classroom management in the teaching and learning of (professional, pedagogic, social and personality competence English and Arabic Language at IAIN Walisongo Semarang. This study is designed quantitavely and qualitatively using closed and open-ended questionnaire for collecting data. The subject of this research is the second semester students of the two faculties at IAIN Walisongo who, in that semester, take Arabic or English language course. The subject is chosen because based on 2012 course distribution, English and Arabic are distributed in the first and the second semester. The findings revealed that it is clearly seen that KPI (Islamic Communication & Broadcasting department students have better perception to their English language teachers. Meanwhile, students who have better perception to their Arabic Language Teachers are those from Islamic Counseling Departments (BPI of Dakwah faculty. Data of Tarbiyah Faculty shows Arabic language teachers are dominating. Arabic language teachers win 0.5 over English language teachers in almost all characteristics. This implies that expected performance of students in English Language is based on the teachers’ attitude, method of teaching the subject and classroom management. Based on the above-findings, recommendations were made.

Subjective well-being and Citizenship dimensions according to individualism and collectivism beliefs among Polish adolescents

OpenAIRE

Anna M. Zalewska; Agnieszka Zawadzka

2016-01-01

Background The aim of the research is to analyse pleasant (subjective well-being – SWB) and meaningful life (Citizenship dimensions) in the context of Horizontal and Vertical Individualism (HI, VI) or Collectivism (HC, VC) values (individual beliefs) among adolescents living in the culture “in between individualism and collectivism”. Participants and procedure Second-year high (111) and secondary (98) school students filled in the Horizontal and Vertical Individualism and ...

Individual differences and subjective workload assessment - Comparing pilots to nonpilots

Science.gov (United States)

Vidulich, Michael A.; Pandit, Parimal

1987-01-01

Results by two groups of subjects, pilots and nonpilots, for two subjective workload assessment techniques (the SWAT and NASA-TLX tests) intended to evaluate individual differences in the perception and reporting of subjective workload are compared with results obtained for several traditional personality tests. The personality tests were found to discriminate between the groups while the workload tests did not. It is concluded that although the workload tests may provide useful information with respect to the interaction between tasks and personality, they are not effective as pure tests of individual differences.

Feel the Time. Time Perception as a Function of Interoceptive Processing

Directory of Open Access Journals (Sweden)

Daniele Di Lernia

2018-03-01

Full Text Available The nature of time is rooted in our body. Constellations of impulses arising from the flesh constantly create our interoceptive perception and, in turn, the unfolding of these perceptions defines human awareness of time. This study explored the connection between time perception and interoception and proposes the Interoceptive Buffer saturation (IBs index. IBs evaluates subjects’ ability to process salient stimuli from the body by measuring subjective distortions of interoceptive time perception, i.e., the estimated duration of tactile interoceptive stimulations. Thirty female healthy subjects were recruited through consecutive sampling and assessed for common variables related to interoceptive alterations: depressive symptoms (Beck Depression Inventory, BDI-II, eating disorders (EDI-3 risk, and anxiety levels (State Trait Anxiety Inventory, STAI. Interoceptive cardiac accuracy (IAc was assessed as well. Subjects performed verbal time estimation of interoceptive stimuli (IBs delivered using a specifically designed interoceptive tactile stimulator, as well as verbal time estimation of visual and auditory stimuli. Results showed that IBs index positively correlated with IAc, and negatively with EDI-3 Drive for Thinness (DT risk subscale. Moreover, IBs index was positively predicted by IAc, and negatively predicted by DT and somatic factors of depression. Our results suggest that underestimations in interoceptive time perception are connected to different psychological conditions characterized by a diminished processing of high salience stimuli from the body. Conversely, overestimations of the duration of interoceptive stimuli appear to be function of subjects’ ability to correctly perceive their own bodily information. Evidence supported IBs index, fostering the concept of interoceptive treatments for clinical purposes.

Participation of rural Zimbabwean female students in mathematics: The influence of perception

Directory of Open Access Journals (Sweden)

Anna Gudyanga

2016-12-01

Full Text Available The study was premised on the influence of perceptions on the participation of Ordinary Level rural African Zimbabwean female students in mathematics. Qualitative research design grounded in the interpretive paradigm was employed. Eighteen Ordinary Level female students and six teachers purposively selected from three rural co-educational secondary schools participated in the study. Data were generated through lesson observations and semi-structured question type interview guide. Findings revealed that rural female students perceived mathematics as a difficult subject, masculine and irrelevant to their future aspirations. Participants outlined that their perceptions were rooted in the prevailing cultural belief that mathematics is a masculine subject and negative stereotypes about girls’ maths abilities. Further findings indicate that female students’ participation in mathematics was highly influenced by their perception towards the subject. These perceptions result in the development of a general negative attitude to the subject that caused fewer female students to participate in mathematics in large numbers. We recommended parents and teachers to work hard to eliminate the negative gender and cultural stereotypes in order to enhance female students’ confidence in mathematics abilities. Schools should employ female mathematics teachers and expose female students to female role models who have succeeded in life in order to encourage more participation of female students in mathematics. Schools are made responsible for smoothing out difficulties generated by the prevailing culture. There is a gap in knowledge base pertaining to the Zimbabwean rural girls’ participation in Mathematics.

International competition in vertically differentiated markets with innovation and imitation: trade policy versus free trade

Czech Academy of Sciences Publication Activity Database

Kováč, Eugen; Žigić, K.

-, č. 336 (2007), s. 1-51 ISSN 1211-3298 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:AV0Z70850503 Keywords : vertical differentiation * free trade * strategic trade policy Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp336.pdf

Strategic trade policy and vertical product differentiation: intra-industry trade between developed and developing countries

Czech Academy of Sciences Publication Activity Database

Kúnin, M.; Žigić, Krešimir

-, č. 230 (2004), s. 1-37 ISSN 1211-3298 R&D Projects: GA AV ČR KSK8002119 Institutional research plan: CEZ:AV0Z7085904 Keywords : vertical differentiation * optimal tariff * quality reversal Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp230.pdf

Vertical axis wind turbine airfoil

Science.gov (United States)

Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich

2012-12-18

A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.

Perception of slipperiness and prospective risk of slipping at work

Science.gov (United States)

Courtney, Theodore K; Verma, Santosh K; Chang, Wen-Ruey; Huang, Yueng-Hsiang; Lombardi, David A; Brennan, Melanye J; Perry, Melissa J

2013-01-01

Objectives Falls are a leading cause of injury at work, and slipping is the predominant cause of falling. Prior research has suggested a modest correlation between objective measures (such as coefficient of friction, COF) and subjective measures of slipperiness (such as worker perceptions) in the workplace. However, the degree of association between subjective measures and the actual risk of slipping at the workplace is unknown. This study examined the association between perception of slipperiness and the risk of slipping. Methods 475 workers from 36 limited-service restaurants participated in a 12-week prospective cohort study. At baseline, demographic information was collected, participants rated floor slipperiness in eight areas of the restaurant, and work environment factors, such as COF, were measured. Restaurant-level and area-level mean perceptions of slipperiness were calculated. Participants then reported their slip experience at work on a weekly basis for the next 12 weeks. The associations between perception of slipperiness and the rate of slipping were assessed. Results Adjusting for age, gender, body mass index, education, primary language, mean COF, use of slip-resistant shoes, and restaurant chain, each 1-point increase in mean restaurant-level perception of slipperiness (4-point scale) was associated with a 2.71 times increase in the rate of slipping (95% CI 1.25 to 5.87). Results were similar for area-level perception within the restaurant (rate ratios (RR) 2.92, 95% CI 2.41 to 3.54). Conclusions Perceptions of slipperiness and the subsequent rate of slipping were strongly associated. These findings suggest that safety professionals, risk managers and employers could use aggregated worker perceptions of slipperiness to identify slipping hazards and, potentially, to assess intervention effectiveness. PMID:22935953

Impact of the focus of attention on vertical jump performance of junior basketball players

OpenAIRE

Manojlović Vladimir; Erčulj Frane

2013-01-01

The aim of the research was to determine the impact of the focus of attention on vertical jump performance expressed through a jump height. Thirteen basketball players (body mass = 73,4 kg, height = 186,58 cm, age = 15.12 ± 0.61 y) volunteered as participants. All the subject represented a club which participated in the Croatian cadets 1. league in season 2008/09, and were tested during the season. The subjects performed two experiments. In both experiments, they performed 15 repetitions of c...

The impact of systemic cortical alterations on perception

Science.gov (United States)

Zhang, Zheng

2011-12-01

Perception is the process of transmitting and interpreting sensory information, and the primary somatosensory (SI) area in the human cortex is the main sensory receptive area for the sensation of touch. The elaborate neuroanatomical connectivity that subserves the neuronal communication between adjacent and near-adjacent regions within sensory cortex has been widely recognized to be essential to normal sensory function. As a result, systemic cortical alterations that impact the cortical regional interaction, as associated with many neurological disorders, are expected to have significant impact on sensory perception. Recently, our research group has developed a novel sensory diagnostic system that employs quantitative sensory testing methods and is able to non-invasively assess central nervous system healthy status. The intent of this study is to utilize quantitative sensory testing methods that were designed to generate discriminable perception to objectively and quantitatively assess the impacts of different conditions on human sensory information processing capacity. The correlation between human perceptions with observations from animal research enables a better understanding of the underlying neurophysiology of human perception. Additional findings on different subject populations provide valuable insight of the underlying mechanisms for the development and maintenance of different neurological diseases. During the course of the study, several protocols were designed and utilized. And this set of sensory-based perceptual metrics was employed to study the effects of different conditions (non-noxious thermal stimulation, chronic pain stage, and normal aging) on sensory perception. It was found that these conditions result in significant deviations of the subjects' tactile information processing capacities from normal values. Although the observed shift of sensory detection sensitivity could be a result of enhanced peripheral activity, the changes in the effects

Cephalometric changes in growing patients with increased vertical dimension treated with cervical headgear.

Science.gov (United States)

Sambataro, Sergio; Fastuca, Rosamaria; Oppermann, Nelson J; Lorusso, Paola; Baccetti, Tiziano; Franchi, Lorenzo; Caprioglio, Alberto

2017-07-01

The aim of the present study was to investigate the cephalometric changes in patients with increased vertical dimension after treatment with cervical headgear compared to controls. The sample of the present retrospective study consisted of 20 Class II patients (10 males, 10 females; mean age 8.54 ± 1.15 years) with increased vertical dimension treated with cervical headgear (treatment group) and 21 Class II patients (11 males, 10 females; mean age 8.41 ± 1.15 years) with increased vertical dimension who underwent no treatment (control group). Cephalograms were available for each subject at baseline (T1) and after treatment/observation time (T2) for both groups and cephalometric analysis allowed for evaluation of changes between time points and between groups. Regarding facial axis, N-ANS/ANS-Me, and overbite, there were no negatively significant changes in the treated group showing no significant worsening in the vertical dimension. Regarding facial angle, there was a significant increase in the treated group between the time points and when compared to the control group, showing counterclockwise rotation of the mandible in the treated group. The vertical dimension was not significantly altered after cervical headgear treatment although the anterior facial height was higher at the beginning of treatment. There was significant counterclockwise rotation of the mandible, and clockwise rotation and distal displacement of the maxilla after treatment.

Risk perception and public concerns of electromagnetic waves from cellular phones in Korea.

Science.gov (United States)

Kim, Kyunghee; Kim, Hae-Joon; Song, Dae Jong; Cho, Yong Min; Choi, Jae Wook

2014-05-01

In this study, the difference between the risk perception of electromagnetic waves from cellular phones and the risk perception of other factors such as environment and food was analyzed. The cause of the difference in the psychological and social factors that affect the group with high risk perception of electromagnetic waves was also analyzed. A questionnaire survey on the risk perception of electromagnetic waves from cellular phones was carried out on 1001 subjects (men and women) over the age of 20. In the group with high risk perception of electromagnetic waves from cellular phones, women had higher risk perception than men. Logistic regression analysis, where the group with high risk perception of electromagnetic waves and the group with low risk perception were used as dependent variables, indicated that the risk perception of electromagnetic waves in women was 1.815 times statistically significantly higher than the risk perception of men (95% CI: 1.340-2.457). Also, high risk perception of electromagnetic waves from cellular phones was observed when the subjects considered that they had more personal knowledge (OR: 1.416, 95% CI: 1.216-1.648), that the seriousness of the risk to future generations was high (OR: 1.410, 95% CI: 1.234-1.611), and their outrage for the occurrence of accidents related to electromagnetic waves was high (OR: 1.460, 95% CI: 1.264-1.686). The results of this study need to be sufficiently considered and reflected in designing the risk communication strategies and communication methods for the preventive measures and advice on electromagnetic waves from cellular phones. © 2014 Wiley Periodicals, Inc.

Vertical and horizontal subsidiarity

Directory of Open Access Journals (Sweden)

Ivan V. Daniluk

2016-02-01

Full Text Available This article makes an attempt to analyze the principle of subsidiarity in its two main manifestations, namely vertical and horizontal, to outline the principles of relations between the state and regions within the vertical subsidiarity, and features a collaboration of the government and civil society within the horizontal subsidiarity. Scientists identify two types, or two levels of the subsidiarity principle: vertical subsidiarity and horizontal subsidiarity. First, vertical subsidiarity (or territorial concerning relations between the state and other levels of subnational government, such as regions and local authorities; second, horizontal subsidiarity (or functional concerns the relationship between state and citizen (and civil society. Vertical subsidiarity expressed in the context of the distribution of administrative responsibilities to the appropriate higher level lower levels relative to the state structure, ie giving more powers to local government. However, state intervention has subsidiary-lower action against local authorities in cases of insolvency last cope on their own, ie higher organisms intervene only if the duties are less authority is insufficient to achieve the goals. Horizontal subsidiarity is within the relationship between power and freedom, and is based on the assumption that the concern for the common good and the needs of common interest community, able to solve community members (as individuals and citizens’ associations and role of government, in accordance horizontal subsidiarity comes to attracting features subsidiarity assistance, programming, coordination and possibly control.

Patients' perceptions, treatment need, and complexity of orthodontic re-treatment

NARCIS (Netherlands)

Ren, Yijin; Boxum, Christo; Sandham, John

The aim of the present study was to investigate the subjective perception and objective treatment need and complexity of patients seeking orthodontic re-treatment. One hundred subjects (66 females, 34 males, age 26.7+/-8.2 years) seeking re-treatment were asked to complete a questionnaire which was

The effect of vertical earthquake component on the uplift of the nuclear reactor building

International Nuclear Information System (INIS)

Kobayashi, Toshio

1986-01-01

During a strong earthquake, the base mat of a nuclear reactor building may be lifted partially by the response overturning moment. And it causes geometrical nonlinear interaction between the base mat and rock foundation beneath it. In order to avoid this uplift phenomena, the base mat and/or plan of the building is enlarged in some cases. These special design need more cost and/or time in construction. In the evaluation of the uplift phenomena, a parameter ''η'' named ''contact ratio'' is used defined as the ratio of compression stress zone area of base mat for total area of base mat. Usually this contact ratio is calculated under the combination of the maximum overturning moment obtained by the linear earthquake response analysis and the normal force by the gravity considering the effect of the vertical earthquake component. In this report, the effect of vertical earthquake component for the uplift phenomena is studied and it concludes that the vertical earthquake component gives little influence on the contact ratio. In order to obtain more reasonable contact retio, the nonlinear rocking analysis subjected to horizontal and vertical earthquake motions simultaneously is proposed in this report. As the second best method, the combination of the maximum overturning moment obtained by linear analysis and the normal force by only the gravity without the vertical earthquake effect is proposed. (author)

Early Stages of Figure–Ground Segregation during Perception of the Face–Vase

Science.gov (United States)

Pitts, Michael A.; Martínez, Antígona; Brewer, James B.; Hillyard, Steven A.

2011-01-01

The temporal sequence of neural processes supporting figure–ground perception was investigated by recording ERPs associated with subjects’ perceptions of the face–vase figure. In Experiment 1, subjects continuously reported whether they perceived the face or the vase as the foreground figure by pressing one of two buttons. Each button press triggered a probe flash to the face region, the vase region, or the borders between the two. The N170/vertex positive potential (VPP) component of the ERP elicited by probes to the face region was larger when subjects perceived the faces as figure. Preceding the N170/VPP, two additional components were identified. First, when the borders were probed, ERPs differed in amplitude as early as 110 msec after probe onset depending on subjects’ figure–ground perceptions. Second, when the face or vase regions were probed, ERPs were more positive (at ~150–200 msec) when that region was perceived as figure versus background. These components likely reflect an early “border ownership” stage, and a subsequent “figure–ground segregation” stage of processing. To explore the influence of attention on these stages of processing, two additional experiments were conducted. In Experiment 2, subjects selectively attended to the face or vase region, and the same early ERP components were again produced. In Experiment 3, subjects performed an identical selective attention task, but on a display lacking distinctive figure–ground borders, and neither of the early components were produced. Results from these experiments suggest sequential stages of processing underlying figure–ground perception, each which are subject to modifications by selective attention. PMID:20146604

Group solution for unsteady free-convection flow from a vertical moving plate subjected to constant heat flux

Science.gov (United States)

Kassem, M.

2006-03-01

The problem of heat and mass transfer in an unsteady free-convection flow over a continuous moving vertical sheet in an ambient fluid is investigated for constant heat flux using the group theoretical method. The nonlinear coupled partial differential equation governing the flow and the boundary conditions are transformed to a system of ordinary differential equations with appropriate boundary conditions. The obtained ordinary differential equations are solved numerically using the shooting method. The effect of Prandlt number on the velocity and temperature of the boundary-layer is plotted in curves. A comparison with previous work is presented.

Vertical sounding balloons for stratospheric photochemistry

Science.gov (United States)

Pommereau, J. P.

The use of vertical sounding balloons for stratospheric photochemistry studies is illustrated by the use of a vertical piloted gas balloon for the search of NO2 diurnal variations. It is shown that the use of montgolfieres (hot air balloons) can enhance the vertical sounding technique. Particular attention is given to a sun-heated montgolfiere and to the more sophisticated infrared montgolfiere that is able to perform three to four vertical excursions per day and to remain aloft for weeks or months.

Metal Oxide Vertical Graphene Hybrid Supercapacitors

Science.gov (United States)

Meyyappan, Meyya (Inventor)

2018-01-01

A metal oxide vertical graphene hybrid supercapacitor is provided. The supercapacitor includes a pair of collectors facing each other, and vertical graphene electrode material grown directly on each of the pair of collectors without catalyst or binders. A separator may separate the vertical graphene electrode materials.

Subjective pain perception during calculus detection with use of a periodontal endoscope.

Science.gov (United States)

Poppe, Kjersta; Blue, Christine

2014-04-01

Periodontal endoscopes are relatively new to the dental field. The purpose of this study was to determine the amount of pain reported by subjects with periodontal disease after experiencing the use of a periodontal endoscope compared with the use of a periodontal probe during calculus detection. A total of 30 subjects with at least 4 sites of 5 to 8 mm pocket depths were treated with scaling and root planing therapy in a split-mouth design. The 2 quadrants were randomly assigned to either S/RP with tactile determination of calculus using an 11/12 explorer, or S/RP treatment with endoscopic detection of calculus. Each subject's pain experience was determined by via a Heft-Parker Visual Analogue Scale (VAS), which measured perceived pain level during periodontal probing and during subgingival visualization via endoscopy. Since subjects expressing some level of dental anxiety generally express increased levels of pain, a pre-treatment survey was also given to determine each subject's level of dental anxiety in order to eliminate dental anxiety as a confounding factor in determining the expressed level of pain. The level of perceived pain was significantly lower with the periodontal endoscope versus the probe (mean VAS 33.0 mm versus 60.2 mm, pdental anxiety did express increased pain levels, but these levels were not statistically significant. Subjects did not find the periodontal endoscope to elicit significant anxiety or pain during subgingival visualization.

When does risk perception predict protection motivation for health threats? A person-by-situation analysis

Science.gov (United States)

Klein, William M. P.; Avishai, Aya; Jones, Katelyn; Villegas, Megan; Sheeran, Paschal

2018-01-01

Although risk perception is a key concept in many health behavior theories, little research has explicitly tested when risk perception predicts motivation to take protective action against a health threat (protection motivation). The present study tackled this question by (a) adopting a multidimensional model of risk perception that comprises deliberative, affective, and experiential components (the TRIRISK model), and (b) taking a person-by-situation approach. We leveraged a highly intensive within-subjects paradigm to test features of the health threat (i.e., perceived severity) and individual differences (e.g., emotion reappraisal) as moderators of the relationship between the three types of risk perception and protection motivation in a within-subjects design. Multi-level modeling of 2968 observations (32 health threats across 94 participants) showed interactions among the TRIRISK components and moderation both by person-level and situational factors. For instance, affective risk perception better predicted protection motivation when deliberative risk perception was high, when the threat was less severe, and among participants who engage less in emotional reappraisal. These findings support the TRIRISK model and offer new insights into when risk perceptions predict protection motivation. PMID:29494705

When does risk perception predict protection motivation for health threats? A person-by-situation analysis.

Science.gov (United States)

Ferrer, Rebecca A; Klein, William M P; Avishai, Aya; Jones, Katelyn; Villegas, Megan; Sheeran, Paschal

2018-01-01

Although risk perception is a key concept in many health behavior theories, little research has explicitly tested when risk perception predicts motivation to take protective action against a health threat (protection motivation). The present study tackled this question by (a) adopting a multidimensional model of risk perception that comprises deliberative, affective, and experiential components (the TRIRISK model), and (b) taking a person-by-situation approach. We leveraged a highly intensive within-subjects paradigm to test features of the health threat (i.e., perceived severity) and individual differences (e.g., emotion reappraisal) as moderators of the relationship between the three types of risk perception and protection motivation in a within-subjects design. Multi-level modeling of 2968 observations (32 health threats across 94 participants) showed interactions among the TRIRISK components and moderation both by person-level and situational factors. For instance, affective risk perception better predicted protection motivation when deliberative risk perception was high, when the threat was less severe, and among participants who engage less in emotional reappraisal. These findings support the TRIRISK model and offer new insights into when risk perceptions predict protection motivation.

Analysis of vertical stability limits and vertical displacement event behavior on NSTX-U

Science.gov (United States)

Boyer, Mark; Battaglia, Devon; Gerhardt, Stefan; Menard, Jonathan; Mueller, Dennis; Myers, Clayton; Sabbagh, Steven; Smith, David

2017-10-01

The National Spherical Torus Experiment Upgrade (NSTX-U) completed its first run campaign in 2016, including commissioning a larger center-stack and three new tangentially aimed neutral beam sources. NSTX-U operates at increased aspect ratio due to the larger center-stack, making vertical stabilization more challenging. Since ST performance is improved at high elongation, improvements to the vertical control system were made, including use of multiple up-down-symmetric flux loop pairs for real-time estimation, and filtering to remove noise. Similar operating limits to those on NSTX (in terms of elongation and internal inductance) were achieved, now at higher aspect ratio. To better understand the observed limits and project to future operating points, a database of vertical displacement events and vertical oscillations observed during the plasma current ramp-up on NSTX/NSTX-U has been generated. Shots were clustered based on the characteristics of the VDEs/oscillations, and the plasma parameter regimes associated with the classes of behavior were studied. Results provide guidance for scenario development during ramp-up to avoid large oscillations at the time of diverting, and provide the means to assess stability of target scenarios for the next campaign. Results will also guide plans for improvements to the vertical control system. Work supported by U.S. D.O.E. Contract No. DE-AC02-09CH11466.

Otolith and Vertical Canal Contributions to Dynamic Postural Control

Science.gov (United States)

Black, F. Owen

1999-01-01

The objective of this project is to determine: 1) how do normal subjects adjust postural movements in response to changing or altered otolith input, for example, due to aging? and 2) how do patients adapt postural control after altered unilateral or bilateral vestibular sensory inputs such as ablative inner ear surgery or ototoxicity, respectively? The following hypotheses are under investigation: 1) selective alteration of otolith input or abnormalities of otolith receptor function will result in distinctive spatial, frequency, and temporal patterns of head movements and body postural sway dynamics. 2) subjects with reduced, altered, or absent vertical semicircular canal receptor sensitivity but normal otolith receptor function or vice versa, should show predictable alterations of body and head movement strategies essential for the control of postural sway and movement. The effect of altered postural movement control upon compensation and/or adaptation will be determined. These experiments provide data for the development of computational models of postural control in normals, vestibular deficient subjects and normal humans exposed to unusual force environments, including orbital space flight.

Student notes as a mediating tool for learning in school subjects

DEFF Research Database (Denmark)

Christensen, Torben Spanget

2016-01-01

-writing function as a tool for a shift in identity from school child to student?. Perceptions of note-writing by two male students and students notes from the school subject bussines economics are analysed. It is concluded that note-writing can function as a tool for learning. Writing notes often allow students...... discource language which must be considered learning subjects. It is concluded that.note writing can mediate between subject discourse language and everyday language, and thereby also function as a tool to identity shift....

Biases in the perception of self-motion during whole-body acceleration and deceleration

Directory of Open Access Journals (Sweden)

Luc eTremblay

2013-12-01

Full Text Available Several studies have investigated whether vestibular signals can be processed to determine the magnitude of passive body motions. Many of them required subjects to report their perceived displacements offline, i.e. after being submitted to passive displacements. Here, we used a protocol that allowed us to complement these results by asking subjects to report their introspective estimation of their displacement continuously, i.e. during the ongoing body rotation. To this end, participants rotated the handle of a manipulandum around a vertical axis to indicate their perceived change of angular position in space at the same time as they were passively rotated in the dark. The rotation acceleration (Acc and deceleration (Dec lasted either 1.5 s (peak of 60 deg/s2, referred to as being "High" or 3 s (peak of 33 deg/s2, referred to as being "Low". The participants were rotated either counter-clockwise or clockwise, and all combinations of acceleration and deceleration were tested (i.e., AccLow-DecLow; AccLow-DecHigh; AccHigh-DecLow; AccHigh-DecHigh. The participants' perception of body rotation was assessed by computing the gain, i.e. ratio between the amplitude of the perceived rotations (as measured by the rotating manipulandum’s handle and the amplitude of the actual chair rotations. The gain was measured at the end of the rotations, and was also computed separately for the acceleration and deceleration phases. Three salient findings resulted from this experiment: i the gain was much greater during body acceleration than during body deceleration, ii the gain was greater during High compared to Low accelerations and iii the gain measured during the deceleration was influenced by the preceding acceleration (i.e., Low or High. These different effects of the angular stimuli on the perception of body motion can be interpreted in relation to the consequences of body acceleration and deceleration on the vestibular system and on higher-order cognitive

Perception of Symmetry in Aesthetic Rhinoplasty Patients: Anthropometric, Demographic, and Psychological Analysis.

Science.gov (United States)

Abbas, Ozan Luay; Kurkcuoglu, Ayla; Aytop, Cigdem Derya; Uysal, Cengiz; Pelin, Can

2017-10-01

Visual perception of symmetry is a major determinant of satisfaction after aesthetic rhinoplasty. In this study, we sought to investigate the existence of any relationship between anthropometric characteristics of the face and visual perceptions of asymmetry among rhinoplasty patients and to evaluate tools that can shed light on patients who appear at high risk for exaggerating potential asymmetries. In the first part, 168 rhinoplasty patients were asked to fill out the demographic questionnaire, nasal shape evaluation scale, and the somatosensory amplification scale. In the second part, we examined the relationship between anthropometric characteristics of the face and visual perceptions of asymmetry using standardized photographs of 100 medical students. In the third part, patients answered the rhinoplasty outcome evaluation questionnaire 6 months after the surgery. Objectively, no symmetrical face was observed in the anthropometric evaluation. Subjectively, only 73% and 54% of the faces were considered asymmetrical by the rhinoplasty and the control groups, respectively. The rate of asymmetry perception was significantly greater in revision patients when compared with primary rhinoplasty patients. The relationship between the rate of subjective perception of asymmetry and the somatosensory amplification scale scores was statistically significant. We found a significant inverse relationship between the rate of asymmetry perception and the rhinoplasty outcome evaluation scores. Plastic surgeons should be aware of this high selectivity in asymmetry perception, which is associated with poor postoperative satisfaction. Somatosensory amplification scale may help identify rhinoplasty patients at a high risk for exaggerating potential asymmetries. III.

Greek perceptions of frontier in Magna Graecia: literature and archaeology in dialogue

Directory of Open Access Journals (Sweden)

Airton POLLINI

2013-07-01

Full Text Available The paper deals with Greek perceptions of frontier in Magna Graecia, from a historical archaeological, contextual standpoint. Considering the complex relationship between literary and archaeological evidence, the paper uses as a case study the frontier in Southern Italy, discussing the subjective frontier perceptions by Greeks and Natives in interaction.

Trade Liberalisation and Vertical Integration

DEFF Research Database (Denmark)

Bache, Peter Arendorf; Laugesen, Anders Rosenstand

We build a three-country model of international trade in final goods and intermediate inputs and study the relation between four different types of trade liberalisation and vertical integration. Firms are heterogeneous with respect to both productivity and factor (headquarter) intensity. Final......-good producers face decisions on exporting, vertical integration of intermediate-input production, and whether the intermediate-input production should be offshored to a low-wage country. We find that the fractions of final-good producers that pursue either vertical integration, offshoring, or exporting are all...... increasing when intermediate-input trade or final-goods trade is liberalised. Finally, we provide guidance for testing the open-economy property rights theory of the firm using firm-level data and surprisingly show that the relationship between factor (headquarter) intensity and the likelihood of vertical...

Composition and vertical distribution of free living and plant parasitic nematodes in hop gardens in the Czech Republic

Czech Academy of Sciences Publication Activity Database

Čermák, V.; Gaar, V.; Háněl, Ladislav; Široká, K.

2011-01-01

Roč. 48, č. 2 (2011), s. 124-136 ISSN 0440-6605 Institutional research plan: CEZ:AV0Z60660521 Keywords : Nematoda * diversity * vertical distribution Subject RIV: EH - Ecology, Behaviour Impact factor: 0.773, year: 2011

The complete vertical stroke ΔS vertical stroke =2-hamiltonian in the next-to-leading order

International Nuclear Information System (INIS)

Herrlich, S.; Nierste, U.

1996-04-01

We present the complete next-to-leading order short-distance QCD corrections to the effective vertical stroke ΔS vertical stroke =2-hamiltonian in the Standard Model. The calculation of the coefficient η 3 is described in great detail. It involves the two-loop mixing of bilocal structures composed of two vertical stroke ΔS vertical stroke =1 operators into vertical stroke ΔS vertical stroke =2 operators. The next-to-leading order corrections enhance η 3 by 27% to η 3 =0.47(+0.03-0.04) thereby affecting the phenomenology of ε K sizeably. η 3 depends on the physical input parameters m t , m c and Λsub(anti M anti S) only weakly. The quoted error stems from renormalization scale dependences, which have reduced compared to the old leading log result. The known calculation of η 1 and η 2 is repeated in order to compare the structure of the three QCD coefficients. We further discuss some field theoretical aspects of the calculation such as the renormalization group equation for Green's functions with two operator insertions and the renormalization scheme dependence caused by the presence of evanescent operators. (orig.)

No auditory experience, no tinnitus: Lessons from subjects with congenital- and acquired single-sided deafness.

Science.gov (United States)

Lee, Sang-Yeon; Nam, Dong Woo; Koo, Ja-Won; De Ridder, Dirk; Vanneste, Sven; Song, Jae-Jin

2017-10-01

Recent studies have adopted the Bayesian brain model to explain the generation of tinnitus in subjects with auditory deafferentation. That is, as the human brain works in a Bayesian manner to reduce environmental uncertainty, missing auditory information due to hearing loss may cause auditory phantom percepts, i.e., tinnitus. This type of deafferentation-induced auditory phantom percept should be preceded by auditory experience because the fill-in phenomenon, namely tinnitus, is based upon auditory prediction and the resultant prediction error. For example, a recent animal study observed the absence of tinnitus in cats with congenital single-sided deafness (SSD; Eggermont and Kral, Hear Res 2016). However, no human studies have investigated the presence and characteristics of tinnitus in subjects with congenital SSD. Thus, the present study sought to reveal differences in the generation of tinnitus between subjects with congenital SSD and those with acquired SSD to evaluate the replicability of previous animal studies. This study enrolled 20 subjects with congenital SSD and 44 subjects with acquired SSD and examined the presence and characteristics of tinnitus in the groups. None of the 20 subjects with congenital SSD perceived tinnitus on the affected side, whereas 30 of 44 subjects with acquired SSD experienced tinnitus on the affected side. Additionally, there were significant positive correlations between tinnitus characteristics and the audiometric characteristics of the SSD. In accordance with the findings of the recent animal study, tinnitus was absent in subjects with congenital SSD, but relatively frequent in subjects with acquired SSD, which suggests that the development of tinnitus should be preceded by auditory experience. In other words, subjects with profound congenital peripheral deafferentation do not develop auditory phantom percepts because no auditory predictions are available from the Bayesian brain. Copyright © 2017 Elsevier B.V. All rights

Heading perception in patients with advanced retinitis pigmentosa

Science.gov (United States)

Li, Li; Peli, Eli; Warren, William H.

2002-01-01

PURPOSE: We investigated whether retinis pigmentosa (RP) patients with residual visual field of < 100 degrees could perceive heading from optic flow. METHODS: Four RP patients and four age-matched normally sighted control subjects viewed displays simulating an observer walking over a ground. In experiment 1, subjects viewed either the entire display with free fixation (full-field condition) or through an aperture with a fixation point at the center (aperture condition). In experiment 2, patients viewed displays of different durations. RESULTS: RP patients' performance was comparable to that of the age-matched control subjects: heading judgment was better in the full-field condition than in the aperture condition. Increasing display duration from 0.5 s to 1 s improved patients' heading performance, but giving them more time (3 s) to gather more visual information did not consistently further improve their performance. CONCLUSIONS: RP patients use active scanning eye movements to compensate for their visual field loss in heading perception; they might be able to gather sufficient optic flow information for heading perception in about 1 s.

Microstructure, vertical strain control and tunable functionalities in self-assembled, vertically aligned nanocomposite thin films

International Nuclear Information System (INIS)

Chen, Aiping; Bi, Zhenxing; Jia, Quanxi; MacManus-Driscoll, Judith L.; Wang, Haiyan

2013-01-01

Vertically aligned nanocomposite (VAN) oxide thin films have recently stimulated a significant amount of research interest owing to their novel architecture, vertical interfacial strain control and tunable material functionalities. In this work, the growth mechanisms of VAN thin films have been investigated by varying the composite material system, the ratio of the two constituent phases, and the thin film growth conditions including deposition temperature and oxygen pressure as well as growth rate. It has been shown that thermodynamic parameters, elastic and interfacial energies and the multiple phase ratio play dominant roles in the resulting microstructure. In addition, vertical interfacial strain has been observed in BiFeO 3 (BFO)- and La 0.7 Sr 0.3 MnO 3 (LSMO)-based VAN thin film systems; the vertical strain could be tuned by the growth parameters and selection of a suitable secondary phase. The tunability of physical properties such as dielectric loss in BFO:Sm 2 O 3 VAN and low-field magnetoresistance in LSMO-based VAN systems has been demonstrated. The enhancement and tunability of those physical properties have been attributed to the unique VAN architecture and vertical strain control. These results suggest that VAN architecture with novel microstructure and unique vertical strain tuning could provide a general route for tailoring and manipulating the functionalities of oxide thin films

Disability perception in Menière's disease: when, how much and why?

Science.gov (United States)

Soto-Varela, Andres; Huertas-Pardo, Belen; Gayoso-Diz, Pilar; Santos-Perez, Sofia; Sanchez-Sellero, Ines

2016-04-01

The purpose of the study was to evaluate self-perceived handicap in patients with definite Menière's disease (MD). A cross-sectional study was conducted. To examine the self-perception of disability, participants completed a DHI (Dizziness Handicap Inventory). Parameters compared with DHI scores: sex, age, unilateral/bilateral affectation, time elapsed since the onset of symptoms, pure-tone average (PTA), stages of MD, audiometric change (last 6 months), PTA in low frequencies (PTAl) and audiometric change in PTAl, subjective perception of fluctuating hearing threshold, tinnitus between attacks, number of vertiginous episodes (last 6 months), time elapsed since last attack, subjective perception of instability intercrises and Tumarkin attacks. 90 patients were included; they completed a total of 104 questionnaires. DHI scores ranged from 2 to 100 (average: 47.08, SD 24.45). In 29 cases (27.9 %) the disability perception was mild, in 43 (41.3 %) moderate, and in 32 (30.8 %) severe. Correlation between disability perception and some vestibular symptoms was found: number of typical attacks (last 6 months), time elapsed since last attack, instability intercrises and Tumarkin attacks. No relationship was found with the rest of variables. Disability perception in patients with MD depends primarily on vestibular symptoms (particularly, instability and frequency of attacks). So, we suggest to design a new staging system of MD taking into account both auditory criteria and also vestibular symptoms.

Subjective memory complaints and their relation with verbal fluency in active older people.

Science.gov (United States)

Bernardes, Flavia Rodrigues; Machado, Camila Kretzer; Souza, Monique Coan; Machado, Marcos José; Belaunde, Aline Megumi Arakawa

2017-05-22

To verify subjective memory complaints and their relation to verbal fluency in older people participating in community groups. An epidemiological quantitative study performed in community groups for older people in Florianópolis, state of Santa Catarina, Brazil. Data were collected by structured interview using the Memory Complaint Questionnaire (MAC-Q) and the Verbal Fluency Test (VFT) by semantic categories "animals/minute". For an inferential descriptive analysis, data with p people in question and added to the questionnaire). We found no relation between subjective memory complaints and verbal fluency of active older people. Mnemonic complaints were correlated to the negative perception of memory and to the duration of the complaint. However, subjective memory complaints were an indicator for those individuals with negative perception of memory, being one aspect that must be considered in older people's speech when investigating a possible cognitive deterioration. Such data can assist in formulating public health care policies aimed at older people in the city, which emphasizes the importance of verifying subjective memory complaints in this population.

Should a Few Null Findings Falsify Prefrontal Theories of Conscious Perception?

Science.gov (United States)

Odegaard, Brian; Knight, Robert T; Lau, Hakwan

2017-10-04

Is activity in prefrontal cortex (PFC) critical for conscious perception? Major theories of consciousness make distinct predictions about the role of PFC, providing an opportunity to arbitrate between these views empirically. Here we address three common misconceptions: (1) PFC lesions do not affect subjective perception; (2) PFC activity does not reflect specific perceptual content; and (3) PFC involvement in studies of perceptual awareness is solely driven by the need to make reports required by the experimental tasks rather than subjective experience per se. These claims are incompatible with empirical findings, unless one focuses only on studies using methods with limited sensitivity. The literature highlights PFC's essential role in enabling the subjective experience in perception, contra the objective capacity to perform visual tasks; conflating the two can also be a source of confusion. Dual Perspectives Companion Paper: Are the Neural Correlates of Consciousness in the Front or in the Back of the Cerebral Cortex? Clinical and Neuroimaging Evidence, by Melanie Boly, Marcello Massimini, Naotsugu Tsuchiya, Bradley R. Postle, Christof Koch, and Giulio Tononi. Copyright © 2017 the authors 0270-6474/17/379593-10$15.00/0.

Vertical market participation

DEFF Research Database (Denmark)

Schrader, Alexander; Martin, Stephen

1998-01-01

Firms that operate at both levels of vertically related Cournot oligopolies will purchase some input supplies from independent rivals, even though they can produce the good at a lower cost, driving up input price for nonintegrated firms at the final good level. Foreclosure, which avoids this stra......Firms that operate at both levels of vertically related Cournot oligopolies will purchase some input supplies from independent rivals, even though they can produce the good at a lower cost, driving up input price for nonintegrated firms at the final good level. Foreclosure, which avoids...

Vertical Protocol Composition

DEFF Research Database (Denmark)

Groß, Thomas; Mödersheim, Sebastian Alexander

2011-01-01

The security of key exchange and secure channel protocols, such as TLS, has been studied intensively. However, only few works have considered what happens when the established keys are actually used—to run some protocol securely over the established “channel”. We call this a vertical protocol.......e., that the combination cannot introduce attacks that the individual protocols in isolation do not have. In this work, we prove a composability result in the symbolic model that allows for arbitrary vertical composition (including self-composition). It holds for protocols from any suite of channel and application...

Music Training and Education Slow the Deterioration of Music Perception Produced by Presbycusis in the Elderly

Directory of Open Access Journals (Sweden)

Felipe N. Moreno-Gómez

2017-05-01

Full Text Available The perception of music depends on the normal function of the peripheral and central auditory system. Aged subjects without hearing loss have altered music perception, including pitch and temporal features. Presbycusis or age-related hearing loss is a frequent condition in elderly people, produced by neurodegenerative processes that affect the cochlear receptor cells and brain circuits involved in auditory perception. Clinically, presbycusis patients have bilateral high-frequency hearing loss and deteriorated speech intelligibility. Music impairments in presbycusis subjects can be attributed to the normal aging processes and to presbycusis neuropathological changes. However, whether presbycusis further impairs music perception remains controversial. Here, we developed a computerized version of the Montreal battery of evaluation of amusia (MBEA and assessed music perception in 175 Chilean adults aged between 18 and 90 years without hearing complaints and in symptomatic presbycusis patients. We give normative data for MBEA performance in a Latin-American population, showing age and educational effects. In addition, we found that symptomatic presbycusis was the most relevant factor determining global MBEA accuracy in aged subjects. Moreover, we show that melodic impairments in presbycusis individuals were diminished by music training, while the performance in temporal tasks were affected by the educational level and music training. We conclude that music training and education are important factors as they can slow the deterioration of music perception produced by age-related hearing loss.

Music Training and Education Slow the Deterioration of Music Perception Produced by Presbycusis in the Elderly.

Science.gov (United States)

Moreno-Gómez, Felipe N; Véliz, Guillermo; Rojas, Marcos; Martínez, Cristián; Olmedo, Rubén; Panussis, Felipe; Dagnino-Subiabre, Alexies; Delgado, Carolina; Delano, Paul H

2017-01-01

The perception of music depends on the normal function of the peripheral and central auditory system. Aged subjects without hearing loss have altered music perception, including pitch and temporal features. Presbycusis or age-related hearing loss is a frequent condition in elderly people, produced by neurodegenerative processes that affect the cochlear receptor cells and brain circuits involved in auditory perception. Clinically, presbycusis patients have bilateral high-frequency hearing loss and deteriorated speech intelligibility. Music impairments in presbycusis subjects can be attributed to the normal aging processes and to presbycusis neuropathological changes. However, whether presbycusis further impairs music perception remains controversial. Here, we developed a computerized version of the Montreal battery of evaluation of amusia (MBEA) and assessed music perception in 175 Chilean adults aged between 18 and 90 years without hearing complaints and in symptomatic presbycusis patients. We give normative data for MBEA performance in a Latin-American population, showing age and educational effects. In addition, we found that symptomatic presbycusis was the most relevant factor determining global MBEA accuracy in aged subjects. Moreover, we show that melodic impairments in presbycusis individuals were diminished by music training, while the performance in temporal tasks were affected by the educational level and music training. We conclude that music training and education are important factors as they can slow the deterioration of music perception produced by age-related hearing loss.

Employee perspectives on individualized pay : Attitudes and fairness perceptions

OpenAIRE

Stråberg, Teresia

2010-01-01

The use of various types of individualized pay setting has increased dramatically in Sweden. In order for individualized pay to work as an incentive, the pay system has to be perceived as fair. This thesis focuses on the various subjective perceptions that arise in relation to individualized pay setting, since such perceptions may have consequences for employee attitudes and behavior. Using survey data from Swedish human service workers (Study I and II) as well as other public employees (Stud...

Neighborhood perceptions and allostatic load

DEFF Research Database (Denmark)

van Deurzen, Ioana; Rod, Naja Hulvej; Christensen, Ulla

2016-01-01

An influential argument explaining why living in certain neighborhoods can become harmful to one's health maintains that individuals can perceive certain characteristics of the neighborhood as threatening and the prolonged exposure to a threatening environment could induce chronic stress. Following...... this line of argumentation, in the present study we test whether subjective perceptions of neighborhood characteristics relate to an objective measure of stress-related physiological functioning, namely allostatic load (AL). We use a large dataset of 5280 respondents living in different regions of Denmark...... and we account for two alternative mechanisms, i.e., the objective characteristics of the living environment and the socio-economic status of individuals. Our results support the chronic stress mechanisms linking neighborhood quality to health. Heightened perceptions of disorder and pollution were found...

Perceptual asymmetry in texture perception.

Science.gov (United States)

Williams, D; Julesz, B

1992-07-15

A fundamental property of human visual perception is our ability to distinguish between textures. A concerted effort has been made to account for texture segregation in terms of linear spatial filter models and their nonlinear extensions. However, for certain texture pairs the ease of discrimination changes when the role of figure and ground are reversed. This asymmetry poses a problem for both linear and nonlinear models. We have isolated a property of texture perception that can account for this asymmetry in discrimination: subjective closure. This property, which is also responsible for visual illusions, appears to be explainable by early visual processes alone. Our results force a reexamination of the process of human texture segregation and of some recent models that were introduced to explain it.

The influence of career orientations on subjective work experiences

Directory of Open Access Journals (Sweden)

Melinde Coetzee

2010-11-01

Research purpose: The study empirically assessed the causal influence of individuals’ career orientations on their perceived life satisfaction, job or career satisfaction, sense of happiness and their perceptions of work as a valuable activity as aspects of their subjective work experiences. Motivation for study: From an organisational perspective, research on individuals’ inner definitions of career success and satisfaction is needed to guide current selection, placement, development, reward and retention practices. Research design, approach and method: A quantitative survey was conducted on a random sample of 2997 participants at predominantly managerial and supervisory level in the service industry. The measuring instruments consisted of an adapted five-factor career orientations model of the Career Orientations Inventory and a 4-item global subjective work experiences scale. Structural equation modelling (SEM was conducted to achieve the aim of the study. Main findings/results: Statistically significant causal relationships were observed between the career orientations and subjective work experiences variables. Practical implications: Individuals’ career orientations influence their general sense of life and job or career satisfaction, happiness and perceptions of work as a valuable activity. Organisations concerned with the retention of staff need to find a way of aligning individuals’ career needs and motives with the goals and aspirations of the organisation. Contribution/value-add: The research confirms the need for assessing the inner career orientations of employees as these provide valuable information regarding the motives and values driving individuals’ career decision making and subjective experiences of their working lives.

Plasticity in the Human Speech Motor System Drives Changes in Speech Perception

Science.gov (United States)

Lametti, Daniel R.; Rochet-Capellan, Amélie; Neufeld, Emily; Shiller, Douglas M.

2014-01-01

Recent studies of human speech motor learning suggest that learning is accompanied by changes in auditory perception. But what drives the perceptual change? Is it a consequence of changes in the motor system? Or is it a result of sensory inflow during learning? Here, subjects participated in a speech motor-learning task involving adaptation to altered auditory feedback and they were subsequently tested for perceptual change. In two separate experiments, involving two different auditory perceptual continua, we show that changes in the speech motor system that accompany learning drive changes in auditory speech perception. Specifically, we obtained changes in speech perception when adaptation to altered auditory feedback led to speech production that fell into the phonetic range of the speech perceptual tests. However, a similar change in perception was not observed when the auditory feedback that subjects' received during learning fell into the phonetic range of the perceptual tests. This indicates that the central motor outflow associated with vocal sensorimotor adaptation drives changes to the perceptual classification of speech sounds. PMID:25080594

Early and late beta-band power reflect audiovisual perception in the McGurk illusion.

Science.gov (United States)

Roa Romero, Yadira; Senkowski, Daniel; Keil, Julian

2015-04-01

The McGurk illusion is a prominent example of audiovisual speech perception and the influence that visual stimuli can have on auditory perception. In this illusion, a visual speech stimulus influences the perception of an incongruent auditory stimulus, resulting in a fused novel percept. In this high-density electroencephalography (EEG) study, we were interested in the neural signatures of the subjective percept of the McGurk illusion as a phenomenon of speech-specific multisensory integration. Therefore, we examined the role of cortical oscillations and event-related responses in the perception of congruent and incongruent audiovisual speech. We compared the cortical activity elicited by objectively congruent syllables with incongruent audiovisual stimuli. Importantly, the latter elicited a subjectively congruent percept: the McGurk illusion. We found that early event-related responses (N1) to audiovisual stimuli were reduced during the perception of the McGurk illusion compared with congruent stimuli. Most interestingly, our study showed a stronger poststimulus suppression of beta-band power (13-30 Hz) at short (0-500 ms) and long (500-800 ms) latencies during the perception of the McGurk illusion compared with congruent stimuli. Our study demonstrates that auditory perception is influenced by visual context and that the subsequent formation of a McGurk illusion requires stronger audiovisual integration even at early processing stages. Our results provide evidence that beta-band suppression at early stages reflects stronger stimulus processing in the McGurk illusion. Moreover, stronger late beta-band suppression in McGurk illusion indicates the resolution of incongruent physical audiovisual input and the formation of a coherent, illusory multisensory percept. Copyright © 2015 the American Physiological Society.

Shared perceptual processes in phoneme and word perception: Evidence from aphasia

Directory of Open Access Journals (Sweden)

Heather Raye Dial

2014-04-01

Replicating previous studies, performance on the two word recognition tasks without closely matched distractors (WAB and PWM was at ceiling for some subjects with impairments on consonant discrimination (see Figures 1a/1b. However, as shown in Figures 1c/1d, for word processing tasks matched in phonological discriminability to the consonant discrimination task, scores on consonant discrimination and word processing were highly correlated, and no individual demonstrated substantially better performance on word than phoneme perception. One patient demonstrated worse performance on lexical decision (d’ = .21 than phoneme perception (d’ = 1.72, which can be attributed to impaired lexical or semantic processing. These data argue against the hypothesis that phoneme and word perception rely on different perceptual processes/routes for processing, and instead indicate that word perception depends on perception of sublexical units.

Acute Improvement of Vertical Jump Performance After Isometric Squats Depends on Knee Angle and Vertical Jumping Ability.

Science.gov (United States)

Tsoukos, Athanasios; Bogdanis, Gregory C; Terzis, Gerasimos; Veligekas, Panagiotis

2016-08-01

Tsoukos, A, Bogdanis, GC, Terzis, G, and Veligekas, P. Acute improvement of vertical jump performance after isometric squats depends on knee angle and vertical jumping ability. J Strength Cond Res 30(8): 2250-2257, 2016-This study examined the acute effects of maximum isometric squats at 2 different knee angles (90 or 140°) on countermovement jump (CMJ) performance in power athletes. Fourteen national-level male track and field power athletes completed 3 main trials (2 experimental and 1 control) in a randomized and counterbalanced order 1 week apart. Countermovement jump performance was evaluated using a force-plate before and 15 seconds, 3, 6, 9, and 12 minutes after 3 sets of 3 seconds maximum isometric contractions with 1-minute rest in between, from a squat position with knee angle set at 90 or 140°. Countermovement jump performance was improved compared with baseline only in the 140° condition by 3.8 ± 1.2% on the 12th minute of recovery (p = 0.027), whereas there was no change in CMJ height in the 90° condition. In the control condition, there was a decrease in CMJ performance over time, reaching -3.6 ± 1.2% (p = 0.049) after 12 minutes of recovery. To determine the possible effects of baseline jump performance on subsequent CMJ performance, subjects were divided into 2 groups ("high jumpers" and "low jumpers"). The baseline CMJ values of "high jumpers" and "low jumpers" differed significantly (CMJ: 45.1 ± 2.2 vs. 37.1 ± 3.9 cm, respectively, p = 0.001). Countermovement jump was increased only in the "high jumpers" group by 5.4 ± 1.4% (p = 0.001) and 7.4 ± 1.2% (p = 0.001) at the knee angles of 90 and 140°, respectively. This improvement was larger at the 140° angle (p = 0.049). Knee angle during isometric squats and vertical jumping ability are important determinants of the acute CMJ performance increase observed after a conditioning activity.

Beyond "Either-Or" Thinking: John Dewey and Confucius on Subject Matter and the Learner

Science.gov (United States)

Tan, Charlene

2016-01-01

This article compares the educational thought of John Dewey and Confucius on the nature of and relationship between subject matter and the learner. There is a common perception in the existing literature and discourse that Dewey advocates child- or learner-centred education whereas Confucius privileges subject matter via textual transmission.…

Relato de caso: transmissão vertical de dengue Case report: vertical dengue infection

Directory of Open Access Journals (Sweden)

Samara L. C. Maroun

2008-12-01

Full Text Available OBJETIVOS: Relatar um caso de transmissão vertical de dengue ocorrido durante epidemia de 2008 pelo vírus tipo II no Rio de Janeiro e revisar a literatura sobre transmissão vertical de dengue. DESCRIÇÃO: Relatamos um caso de transmissão vertical de dengue. Recém-nascido a termo do sexo feminino, peso de nascimento de 3.940 g, foi admitida na unidade de terapia intensiva neonatal com rash cutâneo, hipoatividade e febre no quinto dia de vida. O hemograma evidenciava plaquetopenia importante (38.000 plaquetas. A mãe apresentou quadro clínico compatível com dengue 3 dias antes do parto. Foram colhidos então IgM para dengue da mãe e do recém-nascido, realizados pelo método de ELISA, sendo positivos em ambos. Dengue tipo 2 foi detectado no recém-nascido através de reação em cadeia da polimerase. COMENTÁRIOS: Este relato enfatiza a importância do pediatra estar alerta para a possibilidade de transmissão vertical de dengue iniciando precocemente o tratamento.OBJECTIVES: To report a case of vertical dengue infection in a newborn from Rio de Janeiro, Brazil, and to review the literature concerning this problem. DESCRIPTION: We report a case of vertical dengue infection. Female neonate, birth weight 3,940 g, term, was admitted to a neonatal intensive care unit on the fifth day of life with fever and erythematous rash. Her mother had had dengue fever 3 days before delivery. Her platelet count was 38,000, dropping to 15,000. She did not have any hemorrhagic episodes, including cerebral hemorrhages. Anti-dengue antibodies (IgM were positive in the mother and infant. Dengue type 2 was detected in the infant using polymerase chain reaction. COMMENTS: This report emphasizes that pediatricians should be aware of the possibility of vertical dengue infection so that early management can be instituted.

Subjective perception versus objective indicators of overcrowding and housing affordability

Czech Academy of Sciences Publication Activity Database

Sunega, Petr; Lux, Martin

2016-01-01

Roč. 31, č. 4 (2016), s. 695-717 ISSN 1566-4910 R&D Projects: GA ČR GB14-36154G Institutional support: RVO:68378025 Keywords : Housing * Indicators * Overcrowding * Housing affordability Subject RIV: AO - Sociology, Demography Impact factor: 1.178, year: 2016

Enhancing Critical Thinking: Accounting Students' Perceptions

Science.gov (United States)

Wilkin, Carla L.

2017-01-01

Purpose: The purpose of this paper is to demonstrate how assessment design was used to enhance students' critical thinking in a subject concerned with business enterprise systems. The study shows positive results and favorable perceptions of the merit of the approach. Design/Methodology/Approach: A case study approach was used to examine how the…

Vertical binocular disparity is encoded implicitly within a model neuronal population tuned to horizontal disparity and orientation.

Directory of Open Access Journals (Sweden)

Jenny C A Read

2010-04-01

Full Text Available Primary visual cortex is often viewed as a "cyclopean retina", performing the initial encoding of binocular disparities between left and right images. Because the eyes are set apart horizontally in the head, binocular disparities are predominantly horizontal. Yet, especially in the visual periphery, a range of non-zero vertical disparities do occur and can influence perception. It has therefore been assumed that primary visual cortex must contain neurons tuned to a range of vertical disparities. Here, I show that this is not necessarily the case. Many disparity-selective neurons are most sensitive to changes in disparity orthogonal to their preferred orientation. That is, the disparity tuning surfaces, mapping their response to different two-dimensional (2D disparities, are elongated along the cell's preferred orientation. Because of this, even if a neuron's optimal 2D disparity has zero vertical component, the neuron will still respond best to a non-zero vertical disparity when probed with a sub-optimal horizontal disparity. This property can be used to decode 2D disparity, even allowing for realistic levels of neuronal noise. Even if all V1 neurons at a particular retinotopic location are tuned to the expected vertical disparity there (for example, zero at the fovea, the brain could still decode the magnitude and sign of departures from that expected value. This provides an intriguing counter-example to the common wisdom that, in order for a neuronal population to encode a quantity, its members must be tuned to a range of values of that quantity. It demonstrates that populations of disparity-selective neurons encode much richer information than previously appreciated. It suggests a possible strategy for the brain to extract rarely-occurring stimulus values, while concentrating neuronal resources on the most commonly-occurring situations.

Vestibulo-Ocular Responses to Vertical Translation using a Hand-Operated Chair as a Field Measure of Otolith Function

Science.gov (United States)

Wood, S. J.; Campbell, D. J.; Reschke, M. F.; Prather, L.; Clement, G.

2016-01-01

The translational Vestibulo-Ocular Reflex (tVOR) is an important otolith-mediated response to stabilize gaze during natural locomotion. One goal of this study was to develop a measure of the tVOR using a simple hand-operated chair that provided passive vertical motion. Binocular eye movements were recorded with a tight-fitting video mask in ten healthy subjects. Vertical motion was provided by a modified spring-powered chair (swopper.com) at approximately 2 Hz (+/- 2 cm displacement) to approximate the head motion during walking. Linear acceleration was measured with wireless inertial sensors (Xsens) mounted on the head and torso. Eye movements were recorded while subjects viewed near (0.5m) and far (approximately 4m) targets, and then imagined these targets in darkness. Subjects also provided perceptual estimates of target distances. Consistent with the kinematic properties shown in previous studies, the tVOR gain was greater with near targets, and greater with vision than in darkness. We conclude that this portable chair system can provide a field measure of otolith-ocular function at frequencies sufficient to elicit a robust tVOR.

Network access charges, vertical integration, and property rights structure - experiences from the German electricity markets

International Nuclear Information System (INIS)

Growitsch, C.; Wein, T.

2005-01-01

After the deregulation of the German electricity markets in 1998, the German government opted for a regulatory regime called negotiated third party access, which would be subject to ex-post control by the federal cartel office. Network access charges for new competitors are based on contractual arrangements between energy producers and industrial consumers. As the electricity networks are incontestable natural monopolies, the local and regional network operators are able to set (monopolistic) charges at their own discretion, restricted only by the possible interference of the federal cartel office (Bundeskartellamt). In this paper we analyze if there is evidence for varying charging behaviour depending on the supplier's economic independence (structure of property rights) or its level of vertical integration. For this purpose, we hypothesise that incorporated and vertically integrated suppliers set different charges than independent utility companies. Multivariate estimations show a relation between network access charges and the network operator's economic independence as well as level of vertical integration: on the low voltage level for an estimated annual consumption of 1700 kW/h, vertically integrated firms set-in accordance with our hypothesis-significantly lower access charges than vertically separated suppliers, whereas incorporated network operators charge significantly higher charges compared to independent suppliers. These results could not have been confirmed for other consumptions or voltage levels. (author)

Smile attractiveness. Self-perception and influence on personality.

NARCIS (Netherlands)

Geld, P.A.A.M. van der; Oosterveld, P.; Heck, G.L. van; Kuijpers-Jagtman, A.M.

2007-01-01

OBJECTIVES: To investigate self-perception of smile attractiveness and to determine the role of smile line and other aspects correlated with smile attractiveness and their influence on personality traits. SUBJECTS AND METHODS: Participants judged their smile attractiveness with a patient-specific

A comparison of two landing styles in a two-foot vertical jump.

Science.gov (United States)

Gutiérrez-Davila, Marcos; Campos, José; Navarro, Enrique

2009-01-01

In team sports, such as basketball and volleyball, the players use different takeoff styles to make the vertical jump. The two-foot vertical jump styles have been classified according to the landing style and identified as hop style, when both feet touch the ground at the same time, and step-close style, when there is a slight delay between the first and second foot making contact with the ground. The aim of this research is to identify the differences between the two styles. Twenty-three subjects participated in the study, of whom 14 were volleyball players and 9 were basketball players. The jumps were video recorded and synchronized with two force platforms at 250 Hz. Two temporal periods of the takeoff were defined according to the reduction or increase in the radial distance between the center of gravity (CG) and the foot support (T - RDCG and T + RDCG, respectively). The findings produced no specific advantages when both styles were compared with respect to takeoff velocity and, consequently, to jump height, but takeoff time was significantly shorter (p vertical velocity of CG at the beginning of the takeoff is significantly lower. Moreover, the mean vertical force developed during T - RDCG was reduced by -627.7 +/- 251.1 N, thus lessening impact on landing. Horizontal velocity at the end of the takeoff is less when the step-close style is used (p jumps where it is necessary to move horizontally during the flight against an opponent.

Impact of Long-Term Communication Training on Managerial Style and Perceptions of Organization.

Science.gov (United States)

Cullinane, Laura E.; Stacks, Don W.

A study examined the impact of a working commitment to corporate communication and corporate communication education on perceptions of management and managerial style and the more general perceptions of the organization. Subjects, 15 male mid-level managers at a large southeastern chemical plant that had in place a continuing corporate…

Cognitive dissonance and the perception of natural environments.

Science.gov (United States)

Balcetis, Emily; Dunning, David

2007-10-01

Two studies demonstrated that the motivation to resolve cognitive dissonance affects the visual perception of physical environments. In Study 1, subjects crossed a campus quadrangle wearing a costume reminiscent of Carmen Miranda. In Study 2, subjects pushed themselves up a hill while kneeling on a skateboard. Subjects performed either task under a high-choice, low-choice, or control condition. Subjects in the high-choice conditions, presumably to resolve dissonance, perceived the environment to be less aversive than did subjects in the low-choice and control conditions, seeing a shorter distance to travel (Study 1) and a shallower slope to climb (Study 2). These studies suggest that the impact of motivational states extends from social judgment down into perceptual processes.

Evaluation of vertical coordinate and vertical mixing algorithms in the HYbrid-Coordinate Ocean Model (HYCOM)

Science.gov (United States)

Halliwell, George R.

Vertical coordinate and vertical mixing algorithms included in the HYbrid Coordinate Ocean Model (HYCOM) are evaluated in low-resolution climatological simulations of the Atlantic Ocean. The hybrid vertical coordinates are isopycnic in the deep ocean interior, but smoothly transition to level (pressure) coordinates near the ocean surface, to sigma coordinates in shallow water regions, and back again to level coordinates in very shallow water. By comparing simulations to climatology, the best model performance is realized using hybrid coordinates in conjunction with one of the three available differential vertical mixing models: the nonlocal K-Profile Parameterization, the NASA GISS level 2 turbulence closure, and the Mellor-Yamada level 2.5 turbulence closure. Good performance is also achieved using the quasi-slab Price-Weller-Pinkel dynamical instability model. Differences among these simulations are too small relative to other errors and biases to identify the "best" vertical mixing model for low-resolution climate simulations. Model performance deteriorates slightly when the Kraus-Turner slab mixed layer model is used with hybrid coordinates. This deterioration is smallest when solar radiation penetrates beneath the mixed layer and when shear instability mixing is included. A simulation performed using isopycnic coordinates to emulate the Miami Isopycnic Coordinate Ocean Model (MICOM), which uses Kraus-Turner mixing without penetrating shortwave radiation and shear instability mixing, demonstrates that the advantages of switching from isopycnic to hybrid coordinates and including more sophisticated turbulence closures outweigh the negative numerical effects of maintaining hybrid vertical coordinates.

Social risk perception: recent findings in Spain

International Nuclear Information System (INIS)

Prades-Lopez, A.; Martinez-Arias, R.; Diaz-Hidalgo, M.

1998-01-01

The purpose of this paper is to present our main results from a survey carried out in Spain in the context of social risk perception. This survey is included in a broad project (PRISP) sponsored by the UE and the national Civil Protection Service, and carried out simultaneously in three countries: Spain, Italy and UK. The project combined qualitative and quantitative assessment methods, although only survey results are presented here. A random sample of 600 subjects from two different Spanish communities close to a COMAH chemical site was selected for the research. Main findings regarding, differential perception between both community populations, sex differences, and 'bias perception' of risks among others have been achieved. Main dimensions were obtained by multidimensional scaling and Factor Analysis. Dimensions reported here are similar to the usual findings from the psychometric paradigm. (authors)

Embodied Product Perception: Effects of Verticality Cues in Advertising and Packaging Design on Consumer Impressions and Price Expectations

NARCIS (Netherlands)

van Rompay, Thomas Johannes Lucas; de Vries, Pieter Walter; Bontekoe, F.; Dijkstra, K.

2012-01-01

As consumers increasingly turn to luxury brands and associated benefits, brand managers face the question how to convey luxury perceptions via marketing communications such as packaging and advertising design. Inspired by theories addressing embodied cognition and symbolic meaning portrayal, this

Embodied Product Perception : Effects of Verticality Cues in Advertising and Packaging Design on Consumer Impressions and Price Expectations

NARCIS (Netherlands)

Van Rompay, Thomas J L; De Vries, Peter W.; Bontekoe, Fenna; Tanja-Dijkstra, Karin

2012-01-01

As consumers increasingly turn to luxury brands and associated benefits, brand managers face the question how to convey luxury perceptions via marketing communications such as packaging and advertising design. Inspired by theories addressing embodied cognition and symbolic meaning portrayal, this

Association between perception of dentist oversupply and expectations of dentistry: a survey of dental graduates in Japan.

Science.gov (United States)

Watanabe, Takeshi; Hanioka, Takashi; Yamamoto, Mito; Haresaku, Satoru; Shimada, Kaoru; Naito, Toru

2013-06-01

The perception that there is a surplus of dentists may be an opportunity to explore attractive career options in dentistry in Japan. A self-administered questionnaire was mailed to 2,114 graduates of a private dental school in Japan. We asked about the perception of oversupply, rated by a visual analogue scale, work environment factors, potential areas of dentistry and necessary medical subjects for their dental practice. The association of a strong perception of dentist oversupply with work environment factors, dental areas and medical subjects was examined by multivariate logistic regression analyses. The response rate was 66%, and data from 1,203 community dentists were analysed. Most respondents (76%) perceived either a strong or very strong surplus of dentists. A very strong perception was significantly associated with work environment factors, including practising in large cities and earning the second lowest of four levels of annual income, but no further associations were found with either the number of patients treated or with the other two ranges of income. This perception was negatively associated with the number of necessary medical subjects, specifically otorhinolaryngology, but no significant association was seen with the number of potential areas of dentistry. The negative correlation between the aspiration to acquire medical knowledge and the perception of dentist oversupply under the circumstance of the possibly excessive perception among community dentists invites further research on the benefits of teaching oral medicine to graduate entry students to build future working satisfaction. © 2013 FDI World Dental Federation.

Vertical Drop Of 21-PWR Waste Package On Unyielding Surface

International Nuclear Information System (INIS)

S. Mastilovic; A. Scheider; S.M. Bennett

2001-01-01

The objective of this calculation is to determine the structural response of a 21-PWR (pressurized-water reactor) Waste Package (WP) subjected to the 2-m vertical drop on an unyielding surface at three different temperatures. The scope of this calculation is limited to reporting the calculation results in terms of stress intensities in two different WP components. The information provided by the sketches (Attachment I) is that of the potential design of the type of WP considered in this calculation, and all obtained results are valid for that design only

INFLUENCE OF SUBJECT AND OBJECTIVES FACTORS OF INFORMATIZATION ON THE PEDAGOGICAL DESIGN EFFICIENCY

Directory of Open Access Journals (Sweden)

Tamara O. Pushkareva

2018-02-01

Full Text Available In this article, a preliminary terminological analysis of the conceptual apparatus in the direction of computer-oriented informatization of pedagogical designing of educational activity in the structure of general secondary education has been made. The influence of the subject and object factors of the informatization of the educational process on the efficiency of pedagogical design is investigated. The existence of a dual problem in the educational sphere, related both to the formatting of an effective informational and educational product, and to the technologically acceptable component of well-organized computer-oriented support for students, is established. It is carried out the analysis of priority in the perception of varieties of information by the subjects of the educational system, as well as revealed that in the perception of computer information by subjects of different status or age there are differences that are related to their individual needs, desires, inclinations. The means of informative support of educational process are considered and recommendations on their use are given.

The Influence of Odors on Time Perception

OpenAIRE

Millot, Jean-Louis; Laurent, Lucie; Casini, Laurence

2016-01-01

International audience; The effect of an olfactory stimulation on the perception of time was investigated through two different experiments based on temporal bisection tasks. In experiment 1, the durations to be classified as either short or long were centered on 400 ms while in Experiment 2 there were centered on 2000 ms. The participants were different in the two experiments (36 subjects in each one). In each experiment, half of the subjects learnt the anchor durations when smelling an unpl...

Action and Perception Are Temporally Coupled by a Common Mechanism That Leads to a Timing Misperception

Science.gov (United States)

Astefanoaei, Corina; Daye, Pierre M.; FitzGibbon, Edmond J.; Creanga, Dorina-Emilia; Rufa, Alessandra; Optican, Lance M.

2015-01-01

We move our eyes to explore the world, but visual areas determining where to look next (action) are different from those determining what we are seeing (perception). Whether, or how, action and perception are temporally coordinated is not known. The preparation time course of an action (e.g., a saccade) has been widely studied with the gap/overlap paradigm with temporal asynchronies (TA) between peripheral target onset and fixation point offset (gap, synchronous, or overlap). However, whether the subjects perceive the gap or overlap, and when they perceive it, has not been studied. We adapted the gap/overlap paradigm to study the temporal coupling of action and perception. Human subjects made saccades to targets with different TAs with respect to fixation point offset and reported whether they perceived the stimuli as separated by a gap or overlapped in time. Both saccadic and perceptual report reaction times changed in the same way as a function of TA. The TA dependencies of the time change for action and perception were very similar, suggesting a common neural substrate. Unexpectedly, in the perceptual task, subjects misperceived lights overlapping by less than ∼100 ms as separated in time (overlap seen as gap). We present an attention-perception model with a map of prominence in the superior colliculus that modulates the stimulus signal's effectiveness in the action and perception pathways. This common source of modulation determines how competition between stimuli is resolved, causes the TA dependence of action and perception to be the same, and causes the misperception. PMID:25632126

Rate-distortion theory and human perception.

Science.gov (United States)

Sims, Chris R

2016-07-01

The fundamental goal of perception is to aid in the achievement of behavioral objectives. This requires extracting and communicating useful information from noisy and uncertain sensory signals. At the same time, given the complexity of sensory information and the limitations of biological information processing, it is necessary that some information must be lost or discarded in the act of perception. Under these circumstances, what constitutes an 'optimal' perceptual system? This paper describes the mathematical framework of rate-distortion theory as the optimal solution to the problem of minimizing the costs of perceptual error subject to strong constraints on the ability to communicate or transmit information. Rate-distortion theory offers a general and principled theoretical framework for developing computational-level models of human perception (Marr, 1982). Models developed in this framework are capable of producing quantitatively precise explanations for human perceptual performance, while yielding new insights regarding the nature and goals of perception. This paper demonstrates the application of rate-distortion theory to two benchmark domains where capacity limits are especially salient in human perception: discrete categorization of stimuli (also known as absolute identification) and visual working memory. A software package written for the R statistical programming language is described that aids in the development of models based on rate-distortion theory. Copyright © 2016 The Author. Published by Elsevier B.V. All rights reserved.

Vertical integration and optimal reimbursement policy.

Science.gov (United States)

Afendulis, Christopher C; Kessler, Daniel P

2011-09-01

Health care providers may vertically integrate not only to facilitate coordination of care, but also for strategic reasons that may not be in patients' best interests. Optimal Medicare reimbursement policy depends upon the extent to which each of these explanations is correct. To investigate, we compare the consequences of the 1997 adoption of prospective payment for skilled nursing facilities (SNF PPS) in geographic areas with high versus low levels of hospital/SNF integration. We find that SNF PPS decreased spending more in high integration areas, with no measurable consequences for patient health outcomes. Our findings suggest that integrated providers should face higher-powered reimbursement incentives, i.e., less cost-sharing. More generally, we conclude that purchasers of health services (and other services subject to agency problems) should consider the organizational form of their suppliers when choosing a reimbursement mechanism.

Convergent and Discriminant Validation of Self-Perceptions.

Science.gov (United States)

Soares, Louise M.; Soares, Anthony T.

In order to dimensionalize further the construct of self concept through within-network nomological research, nine different self-scales descriptive of academic settings were administered to students in grades 1-12, their peers, and their teachers. The subjects were administered the Affective Perception Inventory (API), which measures nine…

Epileptic aura and perception of self-control

DEFF Research Database (Denmark)

Lohse, Allan; Kjaer, Troels W; Sabers, Anne

2015-01-01

OBJECTIVE: The health locus of control is the subjective perception of control over one's health. It has been studied for years as one of several factors that determine patient health-related behaviors. The aim of this study was to investigate how the epileptic aura is associated with the health...

Hybrid vertical cavity laser

DEFF Research Database (Denmark)

Chung, Il-Sug; Mørk, Jesper

2010-01-01

A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide.......A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide....

Involuntary attention with uncertainty: peripheral cues improve perception of masked letters, but may impair perception of low-contrast letters.

Science.gov (United States)

Kerzel, Dirk; Gauch, Angélique; Buetti, Simona

2010-10-01

Improvements of perceptual performance following the presentation of peripheral cues have been ascribed to accelerated accrual of information, enhanced contrast perception, and decision bias. We investigated effects of peripheral cues on the perception of Gabor and letter stimuli. Non-predictive, peripheral cues improved perceptual accuracy when the stimuli were masked. In contrast, peripheral cues degraded perception of low-contrast letters and did not affect the perception of low-contrast Gabors. The results suggest that involuntary attention accelerates accrual of information but are not entirely consistent with the idea that involuntary attention enhances subjective contrast. Rather, peripheral cues may cause crowding with single letter targets of low contrast. Further, we investigated the effect of the amount of uncertainty on involuntary attention. Cueing effects were (initially) larger when there were more possible target locations. In addition, cueing effects were larger when error feedback was absent and observers had no knowledge of results. Despite these strategic factors, location uncertainty was not sufficient to produce cueing effects, showing that location uncertainty paired with non-predictive cues reveals perceptual and not (only) decisional processes.

The role of semantic self-perceptions in temporal distance perceptions toward autobiographical events: the semantic congruence model.

Science.gov (United States)

Gebauer, Jochen E; Haddock, Geoffrey; Broemer, Philip; von Hecker, Ulrich

2013-11-01

Why do some autobiographical events feel as if they happened yesterday, whereas others feel like ancient history? Such temporal distance perceptions have surprisingly little to do with actual calendar time distance. Instead, psychologists have found that people typically perceive positive autobiographical events as overly recent, while perceiving negative events as overly distant. The origins of this temporal distance bias have been sought in self-enhancement strivings and mood congruence between autobiographical events and chronic mood. As such, past research exclusively focused on the evaluative features of autobiographical events, while neglecting semantic features. To close this gap, we introduce a semantic congruence model. Capitalizing on the Big Two self-perception dimensions, Study 1 showed that high semantic congruence between recalled autobiographical events and trait self-perceptions render the recalled events subjectively recent. Specifically, interpersonally warm (competent) individuals perceived autobiographical events reflecting warmth (competence) as relatively recent, but warm (competent) individuals did not perceive events reflecting competence (warmth) as relatively recent. Study 2 found that conscious perceptions of congruence mediate these effects. Studies 3 and 4 showed that neither mood congruence nor self-enhancement account for these results. Study 5 extended the results from the Big Two to the Big Five self-perception dimensions, while affirming the independence of the semantic congruence model from evaluative influences. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Flu Shots, Mammogram, and the Perception of Probabilities

NARCIS (Netherlands)

Carman, K.G.; Kooreman, P.

2010-01-01

We study individuals’ decisions to decline or accept preventive health care interventions such as flu shots and mammograms. In particular, we analyze the role of perceptions of the effectiveness of the intervention, by eliciting individuals' subjective probabilities of sickness and survival, with

Directive and nondirective social support in the workplace - is this social support distinction important for subjective health complaints, job satisfaction, and perception of job demands and job control?

Science.gov (United States)

Johnsen, Tone Langjordet; Eriksen, Hege Randi; Indahl, Aage; Tveito, Torill Helene

2018-05-01

Social support is associated with well-being and positive health outcomes. However, positive outcomes of social support might be more dependent on the way support is provided than the amount of support received. A distinction can be made between directive social support, where the provider resumes responsibility, and nondirective social support, where the receiver has the control. This study examined the relationship between directive and nondirective social support, and subjective health complaints, job satisfaction and perception of job demands and job control. A survey was conducted among 957 Norwegian employees, working in 114 private kindergartens (mean age 40.7 years, SD = 10.5, 92.8% female), as part of a randomized controlled trial. This study used only baseline data. A factor analysis of the Norwegian version of the Social Support Inventory was conducted, identifying two factors: nondirective and directive social support. Hierarchical regression analyses were then performed. Nondirective social support was related to fewer musculoskeletal and pseudoneurological complaints, higher job satisfaction, and the perception of lower job demands and higher job control. Directive social support had the opposite relationship, but was not statistically significant for pseudoneurological complaints. It appears that for social support to be positively related with job characteristics and subjective health complaints, it has to be nondirective. Directive social support was not only without any association, but had a significant negative relationship with several of the variables. Nondirective social support may be an important factor to consider when aiming to improve the psychosocial work environment. Clinicaltrials.gov: NCT02396797. Registered 23 March 2015.

Vertical Structure of Radiation-pressure-dominated Thin Disks: Link between Vertical Advection and Convective Stability

International Nuclear Information System (INIS)

Gong, Hong-Yu; Gu, Wei-Min

2017-01-01

In the classic picture of standard thin accretion disks, viscous heating is balanced by radiative cooling through the diffusion process, and the radiation-pressure-dominated inner disk suffers convective instability. However, recent simulations have shown that, owing to the magnetic buoyancy, the vertical advection process can significantly contribute to energy transport. In addition, in comparing the simulation results with the local convective stability criterion, no convective instability has been found. In this work, following on from simulations, we revisit the vertical structure of radiation-pressure-dominated thin disks and include the vertical advection process. Our study indicates a link between the additional energy transport and the convectively stable property. Thus, the vertical advection not only significantly contributes to the energy transport, but it also plays an important role in making the disk convectively stable. Our analyses may help to explain the discrepancy between classic theory and simulations on standard thin disks.

Seeing and identifying with a virtual body decreases pain perception.

Science.gov (United States)

Hänsel, Alexander; Lenggenhager, Bigna; von Känel, Roland; Curatolo, Michele; Blanke, Olaf

2011-09-01

Pain and the conscious mind (or the self) are experienced in our body. Both are intimately linked to the subjective quality of conscious experience. Here, we used virtual reality technology and visuo-tactile conflicts in healthy subjects to test whether experimentally induced changes of bodily self-consciousness (self-location; self-identification) lead to changes in pain perception. We found that visuo-tactile stroking of a virtual body but not of a control object led to increased pressure pain thresholds and self-location. This increase was not modulated by the synchrony of stroking as predicted based on earlier work. This differed for self-identification where we found as predicted that synchrony of stroking increased self-identification with the virtual body (but not a control object), and positively correlated with an increase in pain thresholds. We discuss the functional mechanisms of self-identification, self-location, and the visual perception of human bodies with respect to pain perception. Copyright © 2011 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.

Influence of age, spatial memory, and ocular fixation on localization of auditory, visual, and bimodal targets by human subjects.

Science.gov (United States)

Dobreva, Marina S; O'Neill, William E; Paige, Gary D

2012-12-01

A common complaint of the elderly is difficulty identifying and localizing auditory and visual sources, particularly in competing background noise. Spatial errors in the elderly may pose challenges and even threats to self and others during everyday activities, such as localizing sounds in a crowded room or driving in traffic. In this study, we investigated the influence of aging, spatial memory, and ocular fixation on the localization of auditory, visual, and combined auditory-visual (bimodal) targets. Head-restrained young and elderly subjects localized targets in a dark, echo-attenuated room using a manual laser pointer. Localization accuracy and precision (repeatability) were quantified for both ongoing and transient (remembered) targets at response delays up to 10 s. Because eye movements bias auditory spatial perception, localization was assessed under target fixation (eyes free, pointer guided by foveal vision) and central fixation (eyes fixed straight ahead, pointer guided by peripheral vision) conditions. Spatial localization across the frontal field in young adults demonstrated (1) horizontal overshoot and vertical undershoot for ongoing auditory targets under target fixation conditions, but near-ideal horizontal localization with central fixation; (2) accurate and precise localization of ongoing visual targets guided by foveal vision under target fixation that degraded when guided by peripheral vision during central fixation; (3) overestimation in horizontal central space (±10°) of remembered auditory, visual, and bimodal targets with increasing response delay. In comparison with young adults, elderly subjects showed (1) worse precision in most paradigms, especially when localizing with peripheral vision under central fixation; (2) greatly impaired vertical localization of auditory and bimodal targets; (3) increased horizontal overshoot in the central field for remembered visual and bimodal targets across response delays; (4) greater vulnerability to

Comparing preseason frontal and sagittal plane plyometric programs on vertical jump height in high-school basketball players.

Science.gov (United States)

King, Jeffrey A; Cipriani, Daniel J

2010-08-01

The primary purpose of this study was to evaluate whether frontal plane (FP) plyometrics, which are defined as plyometrics dominated with a lateral component, would produce similar increases in vertical jump height (VJH) compared to sagittal plane (SP) Plyometrics. Thirty-two junior varsity and varsity high-school basketball players participated in 6 weeks of plyometric training. Players participated in either FP or SP plyometrics for the entire study. Vertical jump height was measured on 3 occasions: preintervention (baseline), at week 3 of preparatory training, and at week 6 of training. Descriptive statistics were calculated for VJH. A 2-way analysis of variance (ANOVA) with repeated measures was used to test the difference in mean vertical jump scores using FP and SP training modalities. Results showed a significant effect over time for vertical jump (p training did not have a significant effect on VJH and significant improvement in VJH was seen in subjects participating in SP plyometrics thus reinforcing the specificity principle of training. However, coaches should implement both types of plyometrics because both training modalities can improve power and quickness among basketball players.

A Physician's Perspective On Vertical Integration.

Science.gov (United States)

Berenson, Robert A

2017-09-01

Vertical integration has been a central feature of health care delivery system change for more than two decades. Recent studies have demonstrated that vertically integrated health care systems raise prices and costs without observable improvements in quality, despite many theoretical reasons why cost control and improved quality might occur. Less well studied is how physicians view their newfound partnerships with hospitals. In this article I review literature findings and other observations on five aspects of vertical integration that affect physicians in their professional and personal lives: patients' access to physicians, physician compensation, autonomy versus system support, medical professionalism and culture, and lifestyle. I conclude that the movement toward physicians' alignment with and employment in vertically integrated systems seems inexorable but that policy should not promote such integration either intentionally or inadvertently. Instead, policy should address the flaws in current payment approaches that reward high prices and excessive service use-outcomes that vertical integration currently produces. Project HOPE—The People-to-People Health Foundation, Inc.

Mathematical model of Zika virus with vertical transmission

Directory of Open Access Journals (Sweden)

F.B. Agusto

2017-05-01

Full Text Available Zika is a flavivirus transmitted to humans through either the bites of infected Aedes mosquitoes or sexual transmission. Zika has been linked to congenital anomalies such as microcephaly. In this paper, we analyze a new system of ordinary differential equations which incorporates human vertical transmission of Zika virus, the birth of babies with microcephaly and asymptomatically infected individuals. The Zika model is locally and globally asymptotically stable when the basic reproduction number is less than unity. Our model shows that asymptomatic individuals amplify the disease burden in the community, and the most important parameters for ZIKV spread are the death rate of mosquitoes, the mosquito biting rate, the mosquito recruitment rate, and the transmission per contact to mosquitoes and to adult humans. Scenario exploration indicates that personal-protection is a more effective control strategy than mosquito-reduction strategy. It also shows that delaying conception reduces the number of microcephaly cases, although this does little to prevent Zika transmission in the broader community. However, by coupling aggressive vector control and personal protection use, it is possible to reduce both microcephaly and Zika transmission. 2000 Mathematics Subject Classifications: 92B05, 93A30, 93C15. Keywords: Zika virus, Vertical transmission, Microcephaly, Stability, Control