Heading perception in patients with advanced retinitis pigmentosa.

PubMed

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

2002-09-01

We investigated whether retinis pigmentosa (RP) patients with residual visual field of < 100 degrees could perceive heading from optic flow. 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. 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. 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.

[Virtual audiovisual talking heads: articulatory data and models--applications].

PubMed

Badin, P; Elisei, F; Bailly, G; Savariaux, C; Serrurier, A; Tarabalka, Y

2007-01-01

In the framework of experimental phonetics, our approach to the study of speech production is based on the measurement, the analysis and the modeling of orofacial articulators such as the jaw, the face and the lips, the tongue or the velum. Therefore, we present in this article experimental techniques that allow characterising the shape and movement of speech articulators (static and dynamic MRI, computed tomodensitometry, electromagnetic articulography, video recording). We then describe the linear models of the various organs that we can elaborate from speaker-specific articulatory data. We show that these models, that exhibit a good geometrical resolution, can be controlled from articulatory data with a good temporal resolution and can thus permit the reconstruction of high quality animation of the articulators. These models, that we have integrated in a virtual talking head, can produce augmented audiovisual speech. In this framework, we have assessed the natural tongue reading capabilities of human subjects by means of audiovisual perception tests. We conclude by suggesting a number of other applications of talking heads.

Coordinates of Human Visual and Inertial Heading Perception.

PubMed

Crane, Benjamin Thomas

2015-01-01

Heading estimation involves both inertial and visual cues. Inertial motion is sensed by the labyrinth, somatic sensation by the body, and optic flow by the retina. Because the eye and head are mobile these stimuli are sensed relative to different reference frames and it remains unclear if a perception occurs in a common reference frame. Recent neurophysiologic evidence has suggested the reference frames remain separate even at higher levels of processing but has not addressed the resulting perception. Seven human subjects experienced a 2s, 16 cm/s translation and/or a visual stimulus corresponding with this translation. For each condition 72 stimuli (360° in 5° increments) were delivered in random order. After each stimulus the subject identified the perceived heading using a mechanical dial. Some trial blocks included interleaved conditions in which the influence of ±28° of gaze and/or head position were examined. The observations were fit using a two degree-of-freedom population vector decoder (PVD) model which considered the relative sensitivity to lateral motion and coordinate system offset. For visual stimuli gaze shifts caused shifts in perceived head estimates in the direction opposite the gaze shift in all subjects. These perceptual shifts averaged 13 ± 2° for eye only gaze shifts and 17 ± 2° for eye-head gaze shifts. This finding indicates visual headings are biased towards retina coordinates. Similar gaze and head direction shifts prior to inertial headings had no significant influence on heading direction. Thus inertial headings are perceived in body-centered coordinates. Combined visual and inertial stimuli yielded intermediate results.

Coordinates of Human Visual and Inertial Heading Perception

PubMed Central

Crane, Benjamin Thomas

2015-01-01

Heading estimation involves both inertial and visual cues. Inertial motion is sensed by the labyrinth, somatic sensation by the body, and optic flow by the retina. Because the eye and head are mobile these stimuli are sensed relative to different reference frames and it remains unclear if a perception occurs in a common reference frame. Recent neurophysiologic evidence has suggested the reference frames remain separate even at higher levels of processing but has not addressed the resulting perception. Seven human subjects experienced a 2s, 16 cm/s translation and/or a visual stimulus corresponding with this translation. For each condition 72 stimuli (360° in 5° increments) were delivered in random order. After each stimulus the subject identified the perceived heading using a mechanical dial. Some trial blocks included interleaved conditions in which the influence of ±28° of gaze and/or head position were examined. The observations were fit using a two degree-of-freedom population vector decoder (PVD) model which considered the relative sensitivity to lateral motion and coordinate system offset. For visual stimuli gaze shifts caused shifts in perceived head estimates in the direction opposite the gaze shift in all subjects. These perceptual shifts averaged 13 ± 2° for eye only gaze shifts and 17 ± 2° for eye-head gaze shifts. This finding indicates visual headings are biased towards retina coordinates. Similar gaze and head direction shifts prior to inertial headings had no significant influence on heading direction. Thus inertial headings are perceived in body-centered coordinates. Combined visual and inertial stimuli yielded intermediate results. PMID:26267865

Developmentally Appropriate Practices and Children's Perception of Self-Competence in Head Start Classrooms

ERIC Educational Resources Information Center

Jambunathan, Saigeetha

2012-01-01

The present project studied the relationship between the use of developmentally appropriate practices and children's perception of self-competence in Head Start classrooms. Self-competence is defined as children's confidence in succeeding in certain tasks. Developmentally appropriate practices (DAP) as proposed by the National Association for the…

Teacher Perceptions of Multilevel Policies and the Influence on Nutrition Education in North Carolina Head Start Preschools.

PubMed

Peterson, Amanda D; Goodell, L Suzanne; Hegde, Archana; Stage, Virginia C

2017-05-01

To develop a theory that explains the process of how teachers' perception of multilevel policies may influence nutrition education (NE) teaching strategies in Head Start preschools. Semistructured telephone interviews. North Carolina Head Start preschools. Thirty-two Head Start teachers. All interviews were transcribed verbatim. Following a grounded theory approach, authors coded interview data for emergent themes. Two primary themes emerged during analysis, including teachers' policy perceptions and teacher-perceived influence of policy on NE. A theoretical model was developed to explain how teachers' perceptions of policies influenced NE (eg, teaching strategies) in the classroom. Teachers discussed multiple policy areas governing their classrooms and limiting their ability to provide meaningful and consistent NE. How teachers perceived the level of regulation in the classroom (ie, high or low) influenced the frequency with which they used specific teaching strategies. Despite federal policies supporting the provision of NE, teachers face competing priorities in the classroom (eg, school readiness vs NE) and policies may conflict with standardized NE curricula. To understand how Head Start centers develop local policies, additional research should investigate how administrators interpret federal and state policies. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

The effect of face eccentricity on the perception of gaze direction.

PubMed

Todorović, Dejan

2009-01-01

The perception of a looker's gaze direction depends not only on iris eccentricity (the position of the looker's irises within the sclera) but also on the orientation of the lookers' head. One among several potential cues of head orientation is face eccentricity, the position of the inner features of the face (eyes, nose, mouth) within the head contour, as viewed by the observer. For natural faces this cue is confounded with many other head-orientation cues, but in schematic faces it can be studied in isolation. Salient novel illustrations of the effectiveness of face eccentricity are 'Necker faces', which involve equal iris eccentricities but multiple perceived gaze directions. In four experiments, iris and face eccentricity in schematic faces were manipulated, revealing strong and consistent effects of face eccentricity on perceived gaze direction, with different types of tasks. An additional experiment confirmed the 'Mona Lisa' effect with this type of stimuli. Face eccentricity most likely acted as a simple but robust cue of head turn. A simple computational account of combined effects of cues of eye and head turn on perceived gaze direction is presented, including a formal condition for the perception of direct gaze. An account of the 'Mona Lisa' effect is presented.

Liposuction for Submental Lymphedema Improves Appearance and Self-Perception in the Head and Neck Cancer Patient.

PubMed

Brake, Maria K; Jain, Lauren; Hart, Robert D; Trites, Jonathan R B; Rigby, Matthew; Taylor, S Mark

2014-08-01

Patients who have undergone treatment for head and neck cancer are at risk for neck lymphedema, which can severely affect quality of life. Liposuction has been used successfully for cancer patients who suffer from posttreatment limb lymphedema. The purpose of our study was to review the outcomes of head and neck cancer patients at our center who have undergone submental liposuction for posttreatment lymphedema. Prospective cohort study. Oncology center in tertiary hospital setting. Head and neck cancer patients who underwent submental liposuction for posttreatment lymphedema were included. Nine patients met the study criteria. Patients completed 2 surveys (Modified Blepharoplasty Outcome Evaluation and the validated Derriford Appearance Scale) pre- and postoperatively to assess satisfaction. Patients' pre- and postoperative photos were graded by independent observers to assess outcomes objectively. Our study demonstrated a statistically significant improvement in patients' self-perception of appearance and statistically significant objective scoring of appearance following submental liposuction. Submental liposuction improves the appearance and quality of life for head and neck cancer patients suffering from posttreatment lymphedema by way of improving their self-perception and self-confidence. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

A Case-Based Study with Radiologists Performing Diagnosis Tasks in Virtual Reality.

PubMed

Venson, José Eduardo; Albiero Berni, Jean Carlo; Edmilson da Silva Maia, Carlos; Marques da Silva, Ana Maria; Cordeiro d'Ornellas, Marcos; Maciel, Anderson

2017-01-01

In radiology diagnosis, medical images are most often visualized slice by slice. At the same time, the visualization based on 3D volumetric rendering of the data is considered useful and has increased its field of application. In this work, we present a case-based study with 16 medical specialists to assess the diagnostic effectiveness of a Virtual Reality interface in fracture identification over 3D volumetric reconstructions. We developed a VR volume viewer compatible with both the Oculus Rift and handheld-based head mounted displays (HMDs). We then performed user experiments to validate the approach in a diagnosis environment. In addition, we assessed the subjects' perception of the 3D reconstruction quality, ease of interaction and ergonomics, and also the users opinion on how VR applications can be useful in healthcare. Among other results, we have found a high level of effectiveness of the VR interface in identifying superficial fractures on head CTs.

Head Start Instructional Professionals' Inclusion Perceptions and Practices

ERIC Educational Resources Information Center

Muccio, Leah S.; Kidd, Julie K.; White, C. Stephen; Burns, M. Susan

2014-01-01

This study considered the facilitators and barriers of successful inclusion in Head Start classrooms by examining the perspectives and practices of instructional professionals. A cross-sectional survey design was combined with direct observation in inclusive Head Start classrooms. Survey data were collected from 71 Head Start instructional…

New Phenomenon of Abnormal Auditory Perception Associated with Emotional and Head Trauma: Pathological Confirmation by SPECT Scan

ERIC Educational Resources Information Center

Stephane, Massoud; Hill, Thomas; Matthew, Elizabeth; Folstein, Marshal

2004-01-01

We report the case of an immigrant who suffered from death threats and head trauma while a prisoner of war in Kuwait. Two months later, he began to hear conversations that had taken place previously. These perceptions occurred spontaneously or were induced by the patient's effortful concentration. The single photon emission computerized tomography…

A University Libraries Faculty Perspective on the Role of the Department Head in Faculty Performance: A Grounded Theory Approach. Revised.

ERIC Educational Resources Information Center

Boden, Dana W. R.

This qualitative study examined the perceptions that university library faculty members hold regarding the role of the department head in promoting faculty growth and development. Four faculty members at the University of Nebraska-Lincoln were interviewed. Axial coding of the individuals' perceptions revealed six categories of perceived roles for…

Primary Grade Teachers' Knowledge and Perceptions of Head Lice.

ERIC Educational Resources Information Center

Kirchofer, Gregg M.; Price, James H.; Telljohann, Susan K.

2001-01-01

Surveyed primary school teachers regarding knowledge of head lice, self-efficacy in handling head lice, and preferred information sources. Teachers needed more knowledge about head lice. About half had high efficacy expectations regarding their ability to control the spread of lice. Most reported receiving information from school nurses. Knowledge…

Controlled interaction: strategies for using virtual reality to study perception.

PubMed

Durgin, Frank H; Li, Zhi

2010-05-01

Immersive virtual reality systems employing head-mounted displays offer great promise for the investigation of perception and action, but there are well-documented limitations to most virtual reality systems. In the present article, we suggest strategies for studying perception/action interactions that try to depend on both scale-invariant metrics (such as power function exponents) and careful consideration of the requirements of the interactions under investigation. New data concerning the effect of pincushion distortion on the perception of surface orientation are presented, as well as data documenting the perception of dynamic distortions associated with head movements with uncorrected optics. A review of several successful uses of virtual reality to study the interaction of perception and action emphasizes scale-free analysis strategies that can achieve theoretical goals while minimizing assumptions about the accuracy of virtual simulations.

The Two Faces of Secondary Headship: Women Deputy Head Teachers' Perceptions of the Secondary Head Teacher Role

ERIC Educational Resources Information Center

Guihen, Laura

2017-01-01

Men continue to outnumber women at the secondary head teacher level. This article reports on some of the preliminary findings of a larger study exploring the ways in which women deputy head teachers, as potential aspirants to headship, perceive the secondary head teacher role. Using an Interpretative Phenomenological Analysis methodology,…

Perception of Upright: Multisensory Convergence and the Role of Temporo-Parietal Cortex

PubMed Central

Kheradmand, Amir; Winnick, Ariel

2017-01-01

We inherently maintain a stable perception of the world despite frequent changes in the head, eye, and body positions. Such “orientation constancy” is a prerequisite for coherent spatial perception and sensorimotor planning. As a multimodal sensory reference, perception of upright represents neural processes that subserve orientation constancy through integration of sensory information encoding the eye, head, and body positions. Although perception of upright is distinct from perception of body orientation, they share similar neural substrates within the cerebral cortical networks involved in perception of spatial orientation. These cortical networks, mainly within the temporo-parietal junction, are crucial for multisensory processing and integration that generate sensory reference frames for coherent perception of self-position and extrapersonal space transformations. In this review, we focus on these neural mechanisms and discuss (i) neurobehavioral aspects of orientation constancy, (ii) sensory models that address the neurophysiology underlying perception of upright, and (iii) the current evidence for the role of cerebral cortex in perception of upright and orientation constancy, including findings from the neurological disorders that affect cortical function. PMID:29118736

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

PubMed

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.

The Perception of Auditory Motion

PubMed Central

Leung, Johahn

2016-01-01

The growing availability of efficient and relatively inexpensive virtual auditory display technology has provided new research platforms to explore the perception of auditory motion. At the same time, deployment of these technologies in command and control as well as in entertainment roles is generating an increasing need to better understand the complex processes underlying auditory motion perception. This is a particularly challenging processing feat because it involves the rapid deconvolution of the relative change in the locations of sound sources produced by rotational and translations of the head in space (self-motion) to enable the perception of actual source motion. The fact that we perceive our auditory world to be stable despite almost continual movement of the head demonstrates the efficiency and effectiveness of this process. This review examines the acoustical basis of auditory motion perception and a wide range of psychophysical, electrophysiological, and cortical imaging studies that have probed the limits and possible mechanisms underlying this perception. PMID:27094029

A Role for MST Neurons in Heading Estimation

NASA Technical Reports Server (NTRS)

Stone, L. S.; Perrone, J. A.

1994-01-01

A template model of human visual self-motion perception, which uses neurophysiologically realistic "heading detectors", is consistent with numerous human psychophysical results including the failure of humans to estimate their heading (direction of forward translation) accurately under certain visual conditions. We tested the model detectors with stimuli used by others in single-unit studies. The detectors showed emergent properties similar to those of MST neurons: (1) Sensitivity to non-preferred flow; Each detector is tuned to a specific combination of flow components and its response is systematically reduced by the addition of nonpreferred flow, and (2) Position invariance; The detectors maintain their apparent preference for particular flow components over large regions of their receptive fields. It has been argued that this latter property is incompatible with MST playing a role in heading perception. The model however demonstrates how neurons with the above response properties could still support accurate heading estimation within extrastriate cortical maps.

The perception of (naked only) bodies and faceless heads relies on holistic processing: Evidence from the inversion effect.

PubMed

Bonemei, Rob; Costantino, Andrea I; Battistel, Ilenia; Rivolta, Davide

2018-05-01

Faces and bodies are more difficult to perceive when presented inverted than when presented upright (i.e., stimulus inversion effect), an effect that has been attributed to the disruption of holistic processing. The features that can trigger holistic processing in faces and bodies, however, still remain elusive. In this study, using a sequential matching task, we tested whether stimulus inversion affects various categories of visual stimuli: faces, faceless heads, faceless heads in body context, headless bodies naked, whole bodies naked, headless bodies clothed, and whole bodies clothed. Both accuracy and inversion efficiency score results show inversion effects for all categories but for clothed bodies (with and without heads). In addition, the magnitude of the inversion effect for face, naked body, and faceless heads was similar. Our findings demonstrate that the perception of faces, faceless heads, and naked bodies relies on holistic processing. Clothed bodies (with and without heads), on the other side, may trigger clothes-sensitive rather than body-sensitive perceptual mechanisms. © 2017 The British Psychological Society.

The impact of Chinese cultural values on Taiwan nursing leadership styles: comparing the self-assessments of staff nurses and head nurses.

PubMed

Chang, Yuanmay

2008-06-01

The purpose of this study was to investigate the influence of Chinese culture on nursing leadership behavior in Taiwan nurses. A descriptive study compared staff nurses' assessment of Chinese value in the leadership behavior of their head nurses. Data analysis was made on a convenience sample in Taiwan of 214 head nurses and 2,127 staff nurses who had worked with their head nurse for at least one year. Six medical centers and regional hospitals in northern (Taipei), central (Taichung) and southern (Kaohsiung) Taiwan were recruited for this study. Instruments included the demographic questionnaire, Chinese Value Survey, and Kang's Chinese Leadership Behaviors Module Scale. Results indicated that head nurses scored significantly higher than staff nurses in terms of all cultural values and leadership behaviors. Both staff nurses and head nurses scored the highest mean scores in personal integrity (Yi) and human connectedness (Ren) and the lowest in moral discipline (Li). Staff nurse perceptions of leadership behavior indicated the role of parent to be higher than either the role of director or mentor. Head nurses perceptions of leadership behavior emphasized the role of the director more than either parent or mentor. There were no significant differences between the staff nurses and head nurses in terms of expectative leadership behavior, which gave the role of director higher mean scores than those of either the parent or mentor. Positive and significant associations (r = .266 to r = .334) were found between cultural values and perceptions of leadership behavior. Cultural values predicted 10.6% of leadership behavior variance. The three demographic characteristics of location in northern Taiwan (beta = .09), intention to leave (beta = -.14), and general unit (beta = .10) and the two cultural values of human connectedness (Ren) (beta = .16) and personal integrity (Yi) (beta = .16) together reported a cumulative R2 of 14.6% to explain variance in leadership behavior perceptions. Results of this study identified the important cultural values "Ren" and "Yi". Managers and administrators could add the consideration of such cultural values into nursing leadership to enhance the organization in which Taiwan nurses work.

Virtual head rotation reveals a process of route reconstruction from human vestibular signals

PubMed Central

Day, Brian L; Fitzpatrick, Richard C

2005-01-01

The vestibular organs can feed perceptual processes that build a picture of our route as we move about in the world. However, raw vestibular signals do not define the path taken because, during travel, the head can undergo accelerations unrelated to the route and also be orientated in any direction to vary the signal. This study investigated the computational process by which the brain transforms raw vestibular signals for the purpose of route reconstruction. We electrically stimulated the vestibular nerves of human subjects to evoke a virtual head rotation fixed in skull co-ordinates and measure its perceptual effect. The virtual head rotation caused subjects to perceive an illusory whole-body rotation that was a cyclic function of head-pitch angle. They perceived whole-body yaw rotation in one direction with the head pitched forwards, the opposite direction with the head pitched backwards, and no rotation with the head in an intermediate position. A model based on vector operations and the anatomy and firing properties of semicircular canals precisely predicted these perceptions. In effect, a neural process computes the vector dot product between the craniocentric vestibular vector of head rotation and the gravitational unit vector. This computation yields the signal of body rotation in the horizontal plane that feeds our perception of the route travelled. PMID:16002439

I Am Really Good at Puzzles, but I Don't Get Asked to Play with Others: Age, Gender, and Ethnic Differences in Head Start Children's Self-Perceptions of Competence

ERIC Educational Resources Information Center

Mantzicopoulos, Panayota

2004-01-01

The author examined age, gender, and ethnic differences in the self-perceptions of 112 low-income children who were assessed with the Pictorial Scale of Perceived Competence and Social Acceptance (PSPCSA) at Head Start and kindergarten. Children's self-ratings of competence were overly optimistic across the 4 subscales of the PSPCSA during the 2…

Basic Perception in Head-worn Augmented Reality Displays

DTIC Science & Technology

2012-01-01

Basic Perception in Head-worn Augmented Reality Displays Mark A. Livingston, Joseph L. Gabbard , J. Edward Swan II, Ciara M. Sibley, and Jane H...mark.livingston@nrl.navy.mil Joseph L. Gabbard Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA e-mail: jgabbard@vt.edu J...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 2 Livingston, Gabbard , et al. 1 Introduction For many first-time users of augmented reality

New generation of 3D desktop computer interfaces

NASA Astrophysics Data System (ADS)

Skerjanc, Robert; Pastoor, Siegmund

1997-05-01

Today's computer interfaces use 2-D displays showing windows, icons and menus and support mouse interactions for handling programs and data files. The interface metaphor is that of a writing desk with (partly) overlapping sheets of documents placed on its top. Recent advances in the development of 3-D display technology give the opportunity to take the interface concept a radical stage further by breaking the design limits of the desktop metaphor. The major advantage of the envisioned 'application space' is, that it offers an additional, immediately perceptible dimension to clearly and constantly visualize the structure and current state of interrelations between documents, videos, application programs and networked systems. In this context, we describe the development of a visual operating system (VOS). Under VOS, applications appear as objects in 3-D space. Users can (graphically connect selected objects to enable communication between the respective applications. VOS includes a general concept of visual and object oriented programming for tasks ranging from, e.g., low-level programming up to high-level application configuration. In order to enable practical operation in an office or at home for many hours, the system should be very comfortable to use. Since typical 3-D equipment used, e.g., in virtual-reality applications (head-mounted displays, data gloves) is rather cumbersome and straining, we suggest to use off-head displays and contact-free interaction techniques. In this article, we introduce an autostereoscopic 3-D display and connected video based interaction techniques which allow viewpoint-depending imaging (by head tracking) and visually controlled modification of data objects and links (by gaze tracking, e.g., to pick, 3-D objects just by looking at them).

Head Teachers and Teachers as Pioneers in Facilitating Dyslexic Children in Primary Mainstream Schools

ERIC Educational Resources Information Center

Jaka, Fahima Salman

2015-01-01

This study explores the perceptions of school heads and teachers in facilitating young dyslexic children in primary mainstream schools of Pakistan. Through purposive sampling, the researcher selected eight participants: Four primary school heads and four primary teachers from elite schools of Karachi. The research instrument selected for this…

A Unified Model of Heading and Path Perception in Primate MSTd

PubMed Central

Layton, Oliver W.; Browning, N. Andrew

2014-01-01

Self-motion, steering, and obstacle avoidance during navigation in the real world require humans to travel along curved paths. Many perceptual models have been proposed that focus on heading, which specifies the direction of travel along straight paths, but not on path curvature, which humans accurately perceive and is critical to everyday locomotion. In primates, including humans, dorsal medial superior temporal area (MSTd) has been implicated in heading perception. However, the majority of MSTd neurons respond optimally to spiral patterns, rather than to the radial expansion patterns associated with heading. No existing theory of curved path perception explains the neural mechanisms by which humans accurately assess path and no functional role for spiral-tuned cells has yet been proposed. Here we present a computational model that demonstrates how the continuum of observed cells (radial to circular) in MSTd can simultaneously code curvature and heading across the neural population. Curvature is encoded through the spirality of the most active cell, and heading is encoded through the visuotopic location of the center of the most active cell's receptive field. Model curvature and heading errors fit those made by humans. Our model challenges the view that the function of MSTd is heading estimation, based on our analysis we claim that it is primarily concerned with trajectory estimation and the simultaneous representation of both curvature and heading. In our model, temporal dynamics afford time-history in the neural representation of optic flow, which may modulate its structure. This has far-reaching implications for the interpretation of studies that assume that optic flow is, and should be, represented as an instantaneous vector field. Our results suggest that spiral motion patterns that emerge in spatio-temporal optic flow are essential for guiding self-motion along complex trajectories, and that cells in MSTd are specifically tuned to extract complex trajectory estimation from flow. PMID:24586130

Acoustic pressure waves induced in human heads by RF pulses from high-field MRI scanners.

PubMed

Lin, James C; Wang, Zhangwei

2010-04-01

The current evolution toward greater image resolution from magnetic resonance image (MRI) scanners has prompted the exploration of higher strength magnetic fields and use of higher levels of radio frequencies (RFs). Auditory perception of RF pulses by humans has been reported during MRI with head coils. It has shown that the mechanism of interaction for the auditory effect is caused by an RF pulse-induced thermoelastic pressure wave inside the head. We report a computational study of the intensity and frequency of thermoelastic pressure waves generated by RF pulses in the human head inside high-field MRI and clinical scanners. The U.S. Food and Drug Administration (U.S. FDA) guides limit the local specific absorption rate (SAR) in the body-including the head-to 8 W kg(-1). We present results as functions of SAR and show that for a given SAR the peak acoustic pressures generated in the anatomic head model were essentially the same at 64, 300, and 400 MHz (1.5, 7.0, and 9.4 T). Pressures generated in the anatomic head are comparable to the threshold pressure of 20 mPa for sound perception by humans at the cochlea for 4 W kg(-1). Moreover, results indicate that the peak acoustic pressure in the brain is only 2 to 3 times the auditory threshold at the U.S. FDA guideline of 8 W kg(-1). Even at a high SAR of 20 W kg(-1), where the acoustic pressure in the brain could be more than 7 times the auditory threshold, the sound pressure levels would not be more than 17 db above threshold of perception at the cochlea.

Effect of head pitch and roll orientations on magnetically induced vertigo.

PubMed

Mian, Omar S; Li, Yan; Antunes, Andre; Glover, Paul M; Day, Brian L

2016-02-15

Lying supine in a strong magnetic field, such as in magnetic resonance imaging scanners, can induce a perception of whole-body rotation. The leading hypothesis to explain this invokes a Lorentz force mechanism acting on vestibular endolymph that acts to stimulate semicircular canals. The hypothesis predicts that the perception of whole-body rotation will depend on head orientation in the field. Results showed that the direction and magnitude of apparent whole-body rotation while stationary in a 7 T magnetic field is influenced by head orientation. The data are compatible with the Lorentz force hypothesis of magnetic vestibular stimulation and furthermore demonstrate the operation of a spatial transformation process from head-referenced vestibular signals to Earth-referenced body motion. High strength static magnetic fields are known to induce vertigo, believed to be via stimulation of the vestibular system. The leading hypothesis (Lorentz forces) predicts that the induced vertigo should depend on the orientation of the magnetic field relative to the head. In this study we examined the effect of static head pitch (-80 to +40 deg; 12 participants) and roll (-40 to +40 deg; 11 participants) on qualitative and quantitative aspects of vertigo experienced in the dark by healthy humans when exposed to the static uniform magnetic field inside a 7 T MRI scanner. Three participants were additionally examined at 180 deg pitch and roll orientations. The effect of roll orientation on horizontal and vertical nystagmus was also measured and was found to affect only the vertical component. Vertigo was most discomforting when head pitch was around 60 deg extension and was mildest when it was around 20 deg flexion. Quantitative analysis of vertigo focused on the induced perception of horizontal-plane rotation reported online with the aid of hand-held switches. Head orientation had effects on both the magnitude and the direction of this perceived rotation. The data suggest sinusoidal relationships between head orientation and perception with spatial periods of 180 deg for pitch and 360 deg for roll, which we explain is consistent with the Lorentz force hypothesis. The effects of head pitch on vertigo and previously reported nystagmus are consistent with both effects being driven by a common vestibular signal. To explain all the observed effects, this common signal requires contributions from multiple semicircular canals. © 2015 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.

Motion parallax in immersive cylindrical display systems

NASA Astrophysics Data System (ADS)

Filliard, N.; Reymond, G.; Kemeny, A.; Berthoz, A.

2012-03-01

Motion parallax is a crucial visual cue produced by translations of the observer for the perception of depth and selfmotion. Therefore, tracking the observer viewpoint has become inevitable in immersive virtual (VR) reality systems (cylindrical screens, CAVE, head mounted displays) used e.g. in automotive industry (style reviews, architecture design, ergonomics studies) or in scientific studies of visual perception. The perception of a stable and rigid world requires that this visual cue be coherent with other extra-retinal (e.g. vestibular, kinesthetic) cues signaling ego-motion. Although world stability is never questioned in real world, rendering head coupled viewpoint in VR can lead to the perception of an illusory perception of unstable environments, unless a non-unity scale factor is applied on recorded head movements. Besides, cylindrical screens are usually used with static observers due to image distortions when rendering image for viewpoints different from a sweet spot. We developed a technique to compensate in real-time these non-linear visual distortions, in an industrial VR setup, based on a cylindrical screen projection system. Additionally, to evaluate the amount of discrepancies tolerated without perceptual distortions between visual and extraretinal cues, a "motion parallax gain" between the velocity of the observer's head and that of the virtual camera was introduced in this system. The influence of this artificial gain was measured on the gait stability of free-standing participants. Results indicate that, below unity, gains significantly alter postural control. Conversely, the influence of higher gains remains limited, suggesting a certain tolerance of observers to these conditions. Parallax gain amplification is therefore proposed as a possible solution to provide a wider exploration of space to users of immersive virtual reality systems.

Experiments on the mechanism of underwater hearing.

PubMed

Pau, Hans Wilhelm; Warkentin, Mareike; Specht, Olaf; Krentz, Helga; Herrmann, Anne; Ehrt, Karsten

2011-12-01

The findings suggest that underwater sound perception is realized by the middle ear rather than by bone conduction, at least in shallow water conditions. To prove whether underwater sound perception is effected by bone conduction or by conduction via the middle ear. Five divers, breathing through snorkels, were tested in a swimming pool, to determine whether a sound was louder when the acoustic source placed was in front of the head in comparison with a lateral application facing the ear region. The second experiment investigated whether sound perception is influenced by ear protection plugs in underwater conditions. Also, the effect of a 5 mm thick neoprene hood was determined, with and without an additional perforation in the ear region. Sounds were louder when applied from a position laterally facing the ear, louder without than with a protection plug, louder without than with a neoprene hood on, and louder when the neoprene hood had a perforation in the region of the ear than with an intact hood.

Vestibular signals in primate cortex for self-motion perception.

PubMed

Gu, Yong

2018-04-21

The vestibular peripheral organs in our inner ears detect transient motion of the head in everyday life. This information is sent to the central nervous system for automatic processes such as vestibulo-ocular reflexes, balance and postural control, and higher cognitive functions including perception of self-motion and spatial orientation. Recent neurophysiological studies have discovered a prominent vestibular network in the primate cerebral cortex. Many of the areas involved are multisensory: their neurons are modulated by both vestibular signals and visual optic flow, potentially facilitating more robust heading estimation through cue integration. Combining psychophysics, computation, physiological recording and causal manipulation techniques, recent work has addressed both the encoding and decoding of vestibular signals for self-motion perception. Copyright © 2018. Published by Elsevier Ltd.

The internal representation of head orientation differs for conscious perception and balance control

PubMed Central

Dalton, Brian H.; Rasman, Brandon G.; Inglis, J. Timothy

2017-01-01

Key points We tested perceived head‐on‐feet orientation and the direction of vestibular‐evoked balance responses in passively and actively held head‐turned postures.The direction of vestibular‐evoked balance responses was not aligned with perceived head‐on‐feet orientation while maintaining prolonged passively held head‐turned postures. Furthermore, static visual cues of head‐on‐feet orientation did not update the estimate of head posture for the balance controller.A prolonged actively held head‐turned posture did not elicit a rotation in the direction of the vestibular‐evoked balance response despite a significant rotation in perceived angular head posture.It is proposed that conscious perception of head posture and the transformation of vestibular signals for standing balance relying on this head posture are not dependent on the same internal representation. Rather, the balance system may operate under its own sensorimotor principles, which are partly independent from perception. Abstract Vestibular signals used for balance control must be integrated with other sensorimotor cues to allow transformation of descending signals according to an internal representation of body configuration. We explored two alternative models of sensorimotor integration that propose (1) a single internal representation of head‐on‐feet orientation is responsible for perceived postural orientation and standing balance or (2) conscious perception and balance control are driven by separate internal representations. During three experiments, participants stood quietly while passively or actively maintaining a prolonged head‐turned posture (>10 min). Throughout the trials, participants intermittently reported their perceived head angular position, and subsequently electrical vestibular stimuli were delivered to elicit whole‐body balance responses. Visual recalibration of head‐on‐feet posture was used to determine whether static visual cues are used to update the internal representation of body configuration for perceived orientation and standing balance. All three experiments involved situations in which the vestibular‐evoked balance response was not orthogonal to perceived head‐on‐feet orientation, regardless of the visual information provided. For prolonged head‐turned postures, balance responses consistent with actual head‐on‐feet posture occurred only during the active condition. Our results indicate that conscious perception of head‐on‐feet posture and vestibular control of balance do not rely on the same internal representation, but instead treat sensorimotor cues in parallel and may arrive at different conclusions regarding head‐on‐feet posture. The balance system appears to bypass static visual cues of postural orientation and mainly use other sensorimotor signals of head‐on‐feet position to transform vestibular signals of head motion, a mechanism appropriate for most daily activities. PMID:28035656

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

NASA Technical Reports Server (NTRS)

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 perception weights the sense of the body vertical more heavily early in-flight, that this weighting falls during adaptation to microgravity, and that the decreased reliance on the body vertical persists early post-flight, generating an exaggerated sense of tilt. Since graviceptors respond to linear acceleration and not to head tilt in orbit, it has been proposed that adaptation to weightlessness entails reinterpretation of otolith activity, causing tilt to be perceived as translation. Since linear acceleration during in-flight centrifugation was always perceived as tilt, not translation, the findings do not support this hypothesis.

Contribution of self-motion perception to acoustic target localization.

PubMed

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

2005-05-01

The findings of this study suggest that acoustic spatial perception during head movement is achieved by the vestibular system, which is responsible for the correct dynamic of acoustic target pursuit. The ability to localize sounds in space during whole-body rotation relies on the auditory localization system, which recognizes the position of sound in a head-related frame, and on the sensory systems, namely the vestibular system, which perceive head and body movement. The aim of this study was to analyse the contribution of head motion cues to the spatial representation of acoustic targets in humans. Healthy subjects standing on a rotating platform in the dark were asked to pursue with a laser pointer an acoustic target which was horizontally rotated while the body was kept stationary or maintained stationary while the whole body was rotated. The contribution of head motion to the spatial acoustic representation could be inferred by comparing the gains and phases of the pursuit in the two experimental conditions when the frequency was varied. During acoustic target rotation there was a reduction in the gain and an increase in the phase lag, while during whole-body rotations the gain tended to increase and the phase remained constant. The different contributions of the vestibular and acoustic systems were confirmed by analysing the acoustic pursuit during asymmetric body rotation. In this particular condition, in which self-motion perception gradually diminished, an increasing delay in target pursuit was observed.

Visual perception of axes of head rotation

PubMed Central

Arnoldussen, D. M.; Goossens, J.; van den Berg, A. V.

2013-01-01

Registration of ego-motion is important to accurately navigate through space. Movements of the head and eye relative to space are registered through the vestibular system and optical flow, respectively. Here, we address three questions concerning the visual registration of self-rotation. (1) Eye-in-head movements provide a link between the motion signals received by sensors in the moving eye and sensors in the moving head. How are these signals combined into an ego-rotation percept? We combined optic flow of simulated forward and rotational motion of the eye with different levels of eye-in-head rotation for a stationary head. We dissociated simulated gaze rotation and head rotation by different levels of eye-in-head pursuit. We found that perceived rotation matches simulated head- not gaze-rotation. This rejects a model for perceived self-rotation that relies on the rotation of the gaze line. Rather, eye-in-head signals serve to transform the optic flow's rotation information, that specifies rotation of the scene relative to the eye, into a rotation relative to the head. This suggests that transformed visual self-rotation signals may combine with vestibular signals. (2) Do transformed visual self-rotation signals reflect the arrangement of the semi-circular canals (SCC)? Previously, we found sub-regions within MST and V6+ that respond to the speed of the simulated head rotation. Here, we re-analyzed those Blood oxygenated level-dependent (BOLD) signals for the presence of a spatial dissociation related to the axes of visually simulated head rotation, such as have been found in sub-cortical regions of various animals. Contrary, we found a rather uniform BOLD response to simulated rotation along the three SCC axes. (3) We investigated if subject's sensitivity to the direction of the head rotation axis shows SCC axes specifcity. We found that sensitivity to head rotation is rather uniformly distributed, suggesting that in human cortex, visuo-vestibular integration is not arranged into the SCC frame. PMID:23919087

Exhibition of stochastic resonance in vestibular tilt motion perception.

PubMed

Galvan-Garza, R C; Clark, T K; Mulavara, A P; Oman, C M

2018-04-03

Stochastic Resonance (SR) is a phenomenon broadly described as "noise benefit". The application of subsensory electrical Stochastic Vestibular Stimulation (SVS) via electrodes behind each ear has been used to improve human balance and gait, but its effect on motion perception thresholds has not been examined. This study investigated the capability of subsensory SVS to reduce vestibular motion perception thresholds in a manner consistent with a characteristic bell-shaped SR curve. We measured upright, head-centered, roll tilt Direction Recognition (DR) thresholds in the dark in 12 human subjects with the application of wideband 0-30 Hz SVS ranging from ±0-700 μA. To conservatively assess if SR was exhibited, we compared the proportions of both subjective and statistical SR exhibition in our experimental data to proportions of SR exhibition in multiple simulation cases with varying underlying SR behavior. Analysis included individual and group statistics. As there is not an established mathematical definition, three humans subjectively judged that SR was exhibited in 78% of subjects. "Statistically significant SR exhibition", which additionally required that a subject's DR threshold with SVS be significantly lower than baseline (no SVS), was present in 50% of subjects. Both percentages were higher than simulations suggested could occur simply by chance. For SR exhibitors, defined by subjective or statistically significant criteria, the mean DR threshold improved by -30% and -39%, respectively. The largest individual improvement was -47%. At least half of the subjects were better able to perceive passive body motion with the application of subsensory SVS. This study presents the first conclusive demonstration of SR in vestibular motion perception. Copyright © 2018 Elsevier Inc. All rights reserved.

Does Visual Performance Influence Head Impact Severity Among High School Football Athletes?

PubMed

Schmidt, Julianne D; Guskiewicz, Kevin M; Mihalik, Jason P; Blackburn, J Troy; Siegmund, Gunter P; Marshall, Stephen W

2015-11-01

To compare the odds of sustaining moderate and severe head impacts, rather than mild, between high school football players with high and low visual performance. Prospective quasi-experimental. Clinical Research Center/On-field. Thirty-seven high school varsity football players. Athletes completed the Nike SPARQ Sensory Station visual assessment before the season. Head impact biomechanics were captured at all practices and games using the Head Impact Telemetry System. Each player was classified as either a high or low performer using a median split for each of the following visual performance measures: visual clarity, contrast sensitivity, depth perception, near-far quickness, target capture, perception span, eye-hand coordination, go/no go, and reaction time. We computed the odds of sustaining moderate and severe head impacts against the reference odds of sustaining mild head impacts across groups of high and low performers for each of the visual performance measures. Players with better near-far quickness had increased odds of sustaining moderate [odds ratios (ORs), 1.27; 95% confidence intervals (CIs), 1.04-1.56] and severe head impacts (OR, 1.45; 95% CI, 1.05-2.01) as measured by Head Impact Technology severity profile. High and low performers were at equal odds on all other measures. Better visual performance did not reduce the odds of sustaining higher magnitude head impacts. Visual performance may play less of a role than expected for protecting against higher magnitude head impacts among high school football players. Further research is needed to determine whether visual performance influences concussion risk. Based on our results, we do not recommend using visual training programs at the high school level for the purpose of reducing the odds of sustaining higher magnitude head impacts.

A systematic review of the technology-based assessment of visual perception and exploration behaviour in association football.

PubMed

McGuckian, Thomas B; Cole, Michael H; Pepping, Gert-Jan

2018-04-01

To visually perceive opportunities for action, athletes rely on the movements of their eyes, head and body to explore their surrounding environment. To date, the specific types of technology and their efficacy for assessing the exploration behaviours of association footballers have not been systematically reviewed. This review aimed to synthesise the visual perception and exploration behaviours of footballers according to the task constraints, action requirements of the experimental task, and level of expertise of the athlete, in the context of the technology used to quantify the visual perception and exploration behaviours of footballers. A systematic search for papers that included keywords related to football, technology, and visual perception was conducted. All 38 included articles utilised eye-movement registration technology to quantify visual perception and exploration behaviour. The experimental domain appears to influence the visual perception behaviour of footballers, however no studies investigated exploration behaviours of footballers in open-play situations. Studies rarely utilised representative stimulus presentation or action requirements. To fully understand the visual perception requirements of athletes, it is recommended that future research seek to validate alternate technologies that are capable of investigating the eye, head and body movements associated with the exploration behaviours of footballers during representative open-play situations.

Spared Ability to Perceive Direction of Locomotor Heading and Scene-Relative Object Movement Despite Inability to Perceive Relative Motion

PubMed Central

Vaina, Lucia M.; Buonanno, Ferdinando; Rushton, Simon K.

2014-01-01

Background All contemporary models of perception of locomotor heading from optic flow (the characteristic patterns of retinal motion that result from self-movement) begin with relative motion. Therefore it would be expected that an impairment on perception of relative motion should impact on the ability to judge heading and other 3D motion tasks. Material/Methods We report two patients with occipital lobe lesions whom we tested on a battery of motion tasks. Patients were impaired on all tests that involved relative motion in plane (motion discontinuity, form from differences in motion direction or speed). Despite this they retained the ability to judge their direction of heading relative to a target. A potential confound is that observers can derive information about heading from scale changes bypassing the need to use optic flow. Therefore we ran further experiments in which we isolated optic flow and scale change. Results Patients’ performance was in normal ranges on both tests. The finding that ability to perceive heading can be retained despite an impairment on ability to judge relative motion questions the assumption that heading perception proceeds from initial processing of relative motion. Furthermore, on a collision detection task, SS and SR’s performance was significantly better for simulated forward movement of the observer in the 3D scene, than for the static observer. This suggests that in spite of severe deficits on relative motion in the frontoparlel (xy) plane, information from self-motion helped identification objects moving along an intercept 3D relative motion trajectory. Conclusions This result suggests a potential use of a flow parsing strategy to detect in a 3D world the trajectory of moving objects when the observer is moving forward. These results have implications for developing rehabilitation strategies for deficits in visually guided navigation. PMID:25183375

Modeling heading and path perception from optic flow in the case of independently moving objects

PubMed Central

Raudies, Florian; Neumann, Heiko

2013-01-01

Humans are usually accurate when estimating heading or path from optic flow, even in the presence of independently moving objects (IMOs) in an otherwise rigid scene. To invoke significant biases in perceived heading, IMOs have to be large and obscure the focus of expansion (FOE) in the image plane, which is the point of approach. For the estimation of path during curvilinear self-motion no significant biases were found in the presence of IMOs. What makes humans robust in their estimation of heading or path using optic flow? We derive analytical models of optic flow for linear and curvilinear self-motion using geometric scene models. Heading biases of a linear least squares method, which builds upon these analytical models, are large, larger than those reported for humans. This motivated us to study segmentation cues that are available from optic flow. We derive models of accretion/deletion, expansion/contraction, acceleration/deceleration, local spatial curvature, and local temporal curvature, to be used as cues to segment an IMO from the background. Integrating these segmentation cues into our method of estimating heading or path now explains human psychophysical data and extends, as well as unifies, previous investigations. Our analysis suggests that various cues available from optic flow help to segment IMOs and, thus, make humans' heading and path perception robust in the presence of such IMOs. PMID:23554589

Postural control and perceptive configuration: influence of expertise in gymnastics.

PubMed

Gautier, Geoffroy; Thouvarecq, Régis; Vuillerme, Nicolas

2008-07-01

The purpose of the present experiment was to investigate how postural adaptations to the perceptive configuration are modified by specific gymnastics experience. Two groups, one expert in gymnastics and the other non-expert, had to maintain the erected posture while optical flow was imposed as follows: 20s motionless, 30s approaching motion, and 20s motionless. The centre of pressure and head displacements were analysed. The postural adaptations were characterised by the variability of movements for the flow conditions and by the postural latencies for the flow transitions. The results showed that the gymnasts tended to minimise their body movements and were more stationary (head) but not more stable (COP) than the non-gymnasts. These results suggest that gymnastics experience develops a specific postural adaptability relative to the perceptive configuration. We conclude that a specific postural experience could be considered as an intrinsic constraint, which leads to modification in the patterns of functional adaptation in the perceptive motor space.

A Role for MST Neurons in Heading Estimation

NASA Technical Reports Server (NTRS)

Stone, Leland Scott; Perrone, J. A.; Wade, Charles E. (Technical Monitor)

1994-01-01

A template model of human visual self-motion perception (Perrone, JOSA, 1992; Perrone & Stone, Vis. Res., in press), which uses neurophysiologically realistic "heading detectors", is consistent with numerous human psychophysical results (Warren & Hannon, Nature, 1988; Stone & Perrone, Neuro. Abstr., 1991) including the failure of humans to estimate their heading (direction of forward translation) accurately under certain visual conditions (Royden et al., Nature, 1992). We tested the model detectors with stimuli used by others in- single-unit studies. The detectors showed emergent properties similar to those of MST neurons: 1) Sensitivity to non-preferred flow. Each detector is tuned to a specific combination of flow components and its response is systematically reduced by the addition of nonpreferred flow (Orban et al., PNAS, 1992), and 2) Position invariance. The detectors maintain their apparent preference for particular flow components over large regions of their receptive fields (e.g. Duffy & Wurtz, J. Neurophys., 1991; Graziano et al., J. Neurosci., 1994). It has been argued that this latter property is incompatible with MST playing a role in heading perception. The model however demonstrates how neurons with the above response properties could still support accurate heading estimation within extrastriate cortical maps.

A whole body vibration perception map and associated acceleration loads at the lower leg, hip and head.

PubMed

Sonza, Anelise; Völkel, Nina; Zaro, Milton A; Achaval, Matilde; Hennig, Ewald M

2015-07-01

Whole-body vibration (WBV) training has become popular in recent years. However, WBV may be harmful to the human body. The goal of this study was to determine the acceleration magnitudes at different body segments for different frequencies of WBV. Additionally, vibration sensation ratings by subjects served to create perception vibration magnitude and discomfort maps of the human body. In the first of two experiments, 65 young adults mean (± SD) age range of 23 (± 3.0) years, participated in WBV severity perception ratings, based on a Borg scale. Measurements were performed at 12 different frequencies, two intensities (3 and 5 mm amplitudes) of rotational mode WBV. On a separate day, a second experiment (n = 40) included vertical accelerometry of the head, hip and lower leg with the same WBV settings. The highest lower limb vibration magnitude perception based on the Borg scale was extremely intense for the frequencies between 21 and 25 Hz; somewhat hard for the trunk region (11-25 Hz) and fairly light for the head (13-25 Hz). The highest vertical accelerations were found at a frequency of 23 Hz at the tibia, 9 Hz at the hip and 13 Hz at the head. At 5 mm amplitude, 61.5% of the subjects reported discomfort in the foot region (21-25 Hz), 46.2% for the lower back (17, 19 and 21 Hz) and 23% for the abdominal region (9-13 Hz). The range of 3-7 Hz represents the safest frequency range with magnitudes less than 1 g(*)sec for all studied regions. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

Responses evoked by a vestibular implant providing chronic stimulation.

PubMed

Thompson, Lara A; Haburcakova, Csilla; Gong, Wangsong; Lee, Daniel J; Wall, Conrad; Merfeld, Daniel M; Lewis, Richard F

2012-01-01

Patients with bilateral vestibular loss experience dehabilitating visual, perceptual, and postural difficulties, and an implantable vestibular prosthesis that could improve these symptoms would be of great benefit to these patients. In previous work, we have shown that a one-dimensional, unilateral canal prosthesis can improve the vestibulooccular reflex (VOR) in canal-plugged squirrel monkeys. In addition to the VOR, the potential effects of a vestibular prosthesis on more complex, highly integrative behaviors, such as the perception of head orientation and posture have remained unclear. We tested a one-dimensional, unilateral prosthesis in a rhesus monkey with bilateral vestibular loss and found that chronic electrical stimulation partially restored the compensatory VOR and also that percepts of head orientation relative to gravity were improved. However, the one-dimensional prosthetic stimulation had no clear effect on postural stability during quiet stance, but sway evoked by head-turns was modestly reduced. These results suggest that not only can the implementation of a vestibular prosthesis provide partial restitution of VOR but may also improve perception and posture in the presence of bilateral vestibular hypofunction (BVH). In this review, we provide an overview of our previous and current work directed towards the eventual clinical implementation of an implantable vestibular prosthesis.

3D Visualizations of Abstract DataSets

DTIC Science & Technology

2010-08-01

contrasts no shadows, drop shadows and drop lines. 15. SUBJECT TERMS 3D displays, 2.5D displays, abstract network visualizations, depth perception , human...altitude perception in airspace management and airspace route planning—simulated reality visualizations that employ altitude and heading as well as...cues employed by display designers for depicting real-world scenes on a flat surface can be applied to create a perception of depth for abstract

Spatial reference frames of visual, vestibular, and multimodal heading signals in the dorsal subdivision of the medial superior temporal area.

PubMed

Fetsch, Christopher R; Wang, Sentao; Gu, Yong; Deangelis, Gregory C; Angelaki, Dora E

2007-01-17

Heading perception is a complex task that generally requires the integration of visual and vestibular cues. This sensory integration is complicated by the fact that these two modalities encode motion in distinct spatial reference frames (visual, eye-centered; vestibular, head-centered). Visual and vestibular heading signals converge in the primate dorsal subdivision of the medial superior temporal area (MSTd), a region thought to contribute to heading perception, but the reference frames of these signals remain unknown. We measured the heading tuning of MSTd neurons by presenting optic flow (visual condition), inertial motion (vestibular condition), or a congruent combination of both cues (combined condition). Static eye position was varied from trial to trial to determine the reference frame of tuning (eye-centered, head-centered, or intermediate). We found that tuning for optic flow was predominantly eye-centered, whereas tuning for inertial motion was intermediate but closer to head-centered. Reference frames in the two unimodal conditions were rarely matched in single neurons and uncorrelated across the population. Notably, reference frames in the combined condition varied as a function of the relative strength and spatial congruency of visual and vestibular tuning. This represents the first investigation of spatial reference frames in a naturalistic, multimodal condition in which cues may be integrated to improve perceptual performance. Our results compare favorably with the predictions of a recent neural network model that uses a recurrent architecture to perform optimal cue integration, suggesting that the brain could use a similar computational strategy to integrate sensory signals expressed in distinct frames of reference.

Space flight and neurovestibular adaptation

NASA Technical Reports Server (NTRS)

Reschke, M. F.; Bloomberg, J. J.; Harm, D. L.; Paloski, W. H.

1994-01-01

Space flight represents a form of sensory stimulus rearrangement requiring modification of established terrestrial response patterns through central reinterpretation. Evidence of sensory reinterpretation is manifested as postflight modifications of eye/head coordination, locomotor patterns, postural control strategies, and illusory perceptions of self or surround motion in conjunction with head movements. Under normal preflight conditions, the head is stabilized during locomotion, but immediately postflight reduced head stability, coupled with inappropriate eye/head coordination, results in modifications of gait. Postflight postural control exhibits increased dependence on vision which compensates for inappropriate interpretation of otolith and proprioceptive inputs. Eye movements compensatory for perceived self motion, rather than actual head movements have been observed postflight. Overall, the in-flight adaptive modification of head stabilization strategies, changes in head/eye coordination, illusionary motion, and postural control are maladaptive for a return to the terrestrial environment.

Child Behavior Problems, Teacher Executive Functions, and Teacher Stress in Head Start Classrooms

ERIC Educational Resources Information Center

Friedman-Krauss, Allison H.; Raver, C. Cybele; Neuspiel, Juliana M.; Kinsel, John

2014-01-01

Research Findings: The current article explores the relationship between teachers' perceptions of child behavior problems and preschool teacher job stress, as well as the possibility that teachers' executive functions moderate this relationship. Data came from 69 preschool teachers in 31 early childhood classrooms in 4 Head Start centers and were…

Faculty Member Perceptions of Department Head Leadership Effectiveness at a State University in Turkey

ERIC Educational Resources Information Center

Akbulut, Meltem; Nevra Seggie, Fatma; Börkan, Bengü

2015-01-01

This article examined the leadership effectiveness of department heads at a state university in Turkey using a model of leadership effectiveness that includes the use of multiple leadership roles to manage situations arising from internal and external university environments. Leadership effectiveness was measured by surveying 70 faculty members in…

Head Start Instructional Assistants and Teachers: Culturally Responsive Practice, Children with Disabilities and Ability to Address Each

ERIC Educational Resources Information Center

Assaf, Mona M.

2012-01-01

This qualitative study examined instructional assistants' (IAs) and teachers' perceptions of culturally responsive and quality instructional practices for young children, especially those from various cultural and linguistic backgrounds and those who might have disabilities from low socioeconomic families, in Head Start classrooms. In…

School Heads and Mentors in Cahoots? Challenges to Teaching Practice in Zimbabwean Teacher Education Programmes

ERIC Educational Resources Information Center

Makura, Alfred Henry; Zireva, Davison

2013-01-01

Mentors and school heads play cardinal roles in teacher education programmes in most countries, including Zimbabwe. The side-effects of such symbiosis have not yet been investigated fully. This article used a qualitative methodological approach to investigate the perceptions of some Zimbabwean student teachers regarding their teaching practice…

Nutrition Education Resources in North Carolina-Based Head Start Preschool Programs: Administrator and Teacher Perceptions of Availability and Use.

PubMed

Lisson, Sarah; Goodell, L Suzanne; Dev, Dipti; Wilkerson, Kristi; Hegde, Archana V; Stage, Virginia C

2016-10-01

The purpose of this study was to provide new insight into common barriers to the availability and use of nutrition education (NE) resources in Head Start preschool programs based on administrator and teacher perceptions. In-depth, semistructured phone interviews (n = 63) were conducted with administrators (n = 31) and teachers (n = 32) from North Carolina-based Head Start programs. Interviews were audio-recorded and transcribed verbatim. Data were analyzed qualitatively using content analysis to identify common themes. Five emergent themes were identified within the areas of NE resource availability and use and barriers to NE resource availability and use. Participants expressed desire for greater organization of existing NE material resources, increased community support, and professional development opportunities for teachers specific to NE. Funding and time constraints were reported as affecting NE resources. Creative strategies for addressing NE resource availability and use and barriers (eg, NE integration with educational standards) in Head Start are needed. Copyright © 2016 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Holistic integration of gaze cues in visual face and body perception: Evidence from the composite design.

PubMed

Vrancken, Leia; Germeys, Filip; Verfaillie, Karl

2017-01-01

A considerable amount of research on identity recognition and emotion identification with the composite design points to the holistic processing of these aspects in faces and bodies. In this paradigm, the interference from a nonattended face half on the perception of the attended half is taken as evidence for holistic processing (i.e., a composite effect). Far less research, however, has been dedicated to the concept of gaze. Nonetheless, gaze perception is a substantial component of face and body perception, and holds critical information for everyday communicative interactions. Furthermore, the ability of human observers to detect direct versus averted eye gaze is effortless, perhaps similar to identity perception and emotion recognition. However, the hypothesis of holistic perception of eye gaze has never been tested directly. Research on gaze perception with the composite design could facilitate further systematic comparison with other aspects of face and body perception that have been investigated using the composite design (i.e., identity and emotion). In the present research, a composite design was administered to assess holistic processing of gaze cues in faces (Experiment 1) and bodies (Experiment 2). Results confirmed that eye and head orientation (Experiment 1A) and head and body orientation (Experiment 2A) are integrated in a holistic manner. However, the composite effect was not completely disrupted by inversion (Experiments 1B and 2B), a finding that will be discussed together with implications for future research.

Home-Based Computer Gaming in Vestibular Rehabilitation of Gaze and Balance Impairment.

PubMed

Szturm, Tony; Reimer, Karen M; Hochman, Jordan

2015-06-01

Disease or damage of the vestibular sense organs cause a range of distressing symptoms and functional problems that could include loss of balance, gaze instability, disorientation, and dizziness. A novel computer-based rehabilitation system with therapeutic gaming application has been developed. This method allows different gaze and head movement exercises to be coupled to a wide range of inexpensive, commercial computer games. It can be used in standing, and thus graded balance demands using a sponge pad can be incorporated into the program. A case series pre- and postintervention study was conducted of nine adults diagnosed with peripheral vestibular dysfunction who received a 12-week home rehabilitation program. The feasibility and usability of the home computer-based therapeutic program were established. Study findings revealed that using head rotation to interact with computer games, when coupled to demanding balance conditions, resulted in significant improvements in standing balance, dynamic visual acuity, gaze control, and walking performance. Perception of dizziness as measured by the Dizziness Handicap Inventory also decreased significantly. These preliminary findings provide support that a low-cost home game-based exercise program is well suited to train standing balance and gaze control (with active and passive head motion).

Difference in perception of angular displacement according to applied waveforms.

PubMed

Kushiro, Keisuke; Goto, Fumiyuki

2013-05-01

This study shows that the differences in the waveforms of angular rotation affect the perception and memory of angular displacement. During daily life, when we turn our head during various activities, our brain calculates how much angular displacement our head has undergone. However, how we obtain an accurate estimation of this angular displacement remains unclarified. This study aims to clarify this issue by investigating the perception and memory of passive rotation for three different waveforms of angular velocity rotation (sinusoidal (sine), triangle, and step). Thirteen healthy young subjects sitting on a servo-controlled chair were passively rotated at 60° or 120° about the earth-vertical axis by using one of these three angular velocity waveforms. They then attempted to reproduce the rotation angle by rotating the chair in the same direction in which they had been passively rotated using a handheld controller. The gain (reproduced angle/passively rotated angle) was calculated and used for the evaluation of the perception and memory of angular rotation. The gain for step rotation was larger than that for sine and triangle rotations, with statistical significance. This confirms that the difference in the waveforms of angular rotation affects the perception and memory of angular displacement.

A Robust Camera-Based Interface for Mobile Entertainment

PubMed Central

Roig-Maimó, Maria Francesca; Manresa-Yee, Cristina; Varona, Javier

2016-01-01

Camera-based interfaces in mobile devices are starting to be used in games and apps, but few works have evaluated them in terms of usability or user perception. Due to the changing nature of mobile contexts, this evaluation requires extensive studies to consider the full spectrum of potential users and contexts. However, previous works usually evaluate these interfaces in controlled environments such as laboratory conditions, therefore, the findings cannot be generalized to real users and real contexts. In this work, we present a robust camera-based interface for mobile entertainment. The interface detects and tracks the user’s head by processing the frames provided by the mobile device’s front camera, and its position is then used to interact with the mobile apps. First, we evaluate the interface as a pointing device to study its accuracy, and different factors to configure such as the gain or the device’s orientation, as well as the optimal target size for the interface. Second, we present an in the wild study to evaluate the usage and the user’s perception when playing a game controlled by head motion. Finally, the game is published in an application store to make it available to a large number of potential users and contexts and we register usage data. Results show the feasibility of using this robust camera-based interface for mobile entertainment in different contexts and by different people. PMID:26907288

Dermatography (Medical Tattooing) for Scars and Skin Grafts in Head and Neck Patients to Improve Appearance and Quality of Life.

PubMed

Drost, Brigitte H; van de Langenberg, Rick; Manusama, Olivia R; Janssens, A Soe; Sikorska, Karolina; Zuur, C Lot; Klop, Willem M C; Lohuis, Peter J F M

2017-01-01

Dermatography (medical tattooing) is often overlooked as an adjuvant procedure to improve color mismatch in the head and neck area, and its effect on patient satisfaction and quality of life has not been evaluated, to our knowledge. To analyze the effect of dermatography on the subjective perception of the appearance of scars and skin grafts and the quality of life in head and neck patients. Case series of patients undergoing dermatography at the Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, between July 1, 2007, and April 1, 2015. Participants were invited to respond to 2 questionnaires measuring their scar or graft appearance and their quality of life before and after dermatography as an adjuvant treatment for benign or malignant head and neck tumors. Use of dermatography. Two questionnaires evaluating a visual analog scale score (range, 0-10) and multiple questions on a 5-point scale focusing on satisfaction with the appearance and the quality of life. Among 76 patients, 56 (74%) were included in the study. The mean (SD) age of the study cohort was 56.5 (16.0) years, and 42 (75%) were female. The mean improvement in scar or skin graft perception on the visual analog scale of the modified Utrecht Questionnaire for Outcome Assessment in Aesthetic Rhinoplasty before and after dermatography was 4 points. On the modified Patient Scar Assessment Questionnaire, uniform improvement of approximately 1 point across 9 questions was observed. The answers to all patient satisfaction and quality-of-life questions on both questionnaires improved significantly after dermatography. Dermatography is an effectual adjuvant procedure to improve the subjective perception of scar and skin graft appearance and the quality of life in head and neck patients. 4.

Where’s Your Phone? A Survey of Where Women Aged 15-40 Carry Their Smartphone and Related Risk Perception: A Survey and Pilot Study

PubMed Central

2017-01-01

Smartphones are now owned by most young adults in many countries. Installed applications regularly update while the phone is in standby. If it is kept near the body, this can lead to considerably higher exposure to radiofrequency electromagnetic radiation than occurred without internet access. Very little is known about current smartphone carrying habits of young women. This survey used an online questionnaire to ask about smartphone location under several circumstances to inform the power calculation for a women’s health study. They were also asked about risk perceptions. Data was analysed using Pearson chi square. Three age categories were made: 15–20, 21–30, 31–40. Smartphones were generally kept on standby (96% by day, 83% at night). Of all participants, in the last week the most common locations of the phone when not in use or during passive use was off-body (86%), in the hand (58%), a skirt/trouser pocket (57%), or against the breast (15%). Pocket and near-the-breast storage were significant by age (χ215.04, p = 0.001 and χ210.96, p = 0.04, respectively), both positively influenced by the youngest group. The same influence lay in the association between holding the phone (χ211.082, p = 0.004) and pocket-storage (χ219.971, p<0.001) during passive use. For calls, 36.5% solely used the phone against the head. More than half kept the phone 20–50 cms from their head at night (53%), while 13% kept it closer than 20 cms. Many (36%) thought RF-EMR exposure was related to health problems while 16% did not. There was no relationship between thinking RF-EMR exposure causes health problems in general and carrying the phone against the upper or lower body (p = 0.69 and p = 0.212, respectively). However, calls with the phone against the head were positively related to perception of health risk (χ2 6.695, p = 0.035). Our findings can be used in the power calculation for a case-control study. PMID:28060844

Simulated microgravity [bed rest] has little influence on taste, odor or trigeminal sensitivity

NASA Technical Reports Server (NTRS)

Vickers, Z. M.; Rice, B. L.; Rose, M. S.; Lane, H. W.

2001-01-01

Anecdotal evidence suggests that astronauts' perceptions of foods in space flight may differ from their perceptions of the same foods on Earth. Fluid shifts toward the head experienced in space may alter the astronauts' sensitivity to odors and tastes, producing altered perceptions. Our objective was to determine whether head-down bed rest, which produces similar fluid shifts, would produce changes in sensitivity to taste, odor or trigeminal sensations. Six subjects were rested three times prior to bed rest, three times during bed rest and two times after bed rest to determine their threshold sensitivity to the odors isoamylbutyrate and menthone, the tastants sucrose, sodium chloride, citric acid, quinine and monosodium glutamate, and to capsaicin. Thresholds were measured using a modified staircase procedure. Self-reported congestion was also recorded at each test time. Thresholds for monosodium glutamate where slightly higher during bed rest. None of the other thresholds were altered by bed rest.

Passive perception system for day/night autonomous off-road navigation

NASA Astrophysics Data System (ADS)

Rankin, Arturo L.; Bergh, Charles F.; Goldberg, Steven B.; Bellutta, Paolo; Huertas, Andres; Matthies, Larry H.

2005-05-01

Passive perception of terrain features is a vital requirement for military related unmanned autonomous vehicle operations, especially under electromagnetic signature management conditions. As a member of Team Raptor, the Jet Propulsion Laboratory developed a self-contained passive perception system under the DARPA funded PerceptOR program. An environmentally protected forward-looking sensor head was designed and fabricated in-house to straddle an off-the-shelf pan-tilt unit. The sensor head contained three color cameras for multi-baseline daytime stereo ranging, a pair of cooled mid-wave infrared cameras for nighttime stereo ranging, and supporting electronics to synchronize captured imagery. Narrow-baseline stereo provided improved range data density in cluttered terrain, while wide-baseline stereo provided more accurate ranging for operation at higher speeds in relatively open areas. The passive perception system processed stereo images and outputted over a local area network terrain maps containing elevation, terrain type, and detected hazards. A novel software architecture was designed and implemented to distribute the data processing on a 533MHz quad 7410 PowerPC single board computer under the VxWorks real-time operating system. This architecture, which is general enough to operate on N processors, has been subsequently tested on Pentium-based processors under Windows and Linux, and a Sparc based-processor under Unix. The passive perception system was operated during FY04 PerceptOR program evaluations at Fort A. P. Hill, Virginia, and Yuma Proving Ground, Arizona. This paper discusses the Team Raptor passive perception system hardware and software design, implementation, and performance, and describes a road map to faster and improved passive perception.

[Head masters' perception of school-based hostility in Alicante, Spain: a qualitative study].

PubMed

Martínez Fernández, Carmen; Hernández-Aguado, Ildefonso; Torres Cantero, Alberto M

2006-01-01

There is growing social concern about school violence but little is known about how this situation is experienced in the schools. The objective of this study was to know the perception that School's head masters have of the school-based hostility, on their causes, how they value current preventive strategies, and their recommendations to develop future preventive interventions. We conducted an exploratory study with 14 semistructured interviews of School's head masters. Interviews were conducted at the Schools between May and June 2003 in 1 independent school, 9 state comprehensive schools, and 4 other comprehensive schools within the city of Alicante. The perception of the head masters is that the prevalence of violence is low, more verbal than physical and within gender. They identify lack of punctuality, absenteeism and lack of interest as forms of hostility. As causes they identified age, family problems, school environment, society, media (TV and video-games) and poor language skills. Preventive methods in use were, on one hand, extra-lessons and transversal contents foreseen in the Education Law and common to all schools, and, on the other hand, ideological and pedagogical contents which were specific of some centres. Recommendations focused in demands for increased economic support and skilled human resources. School-based violence is not perceived as an alarming school issue, nor by its magnitude neither by the immediate causes and students' characteristics to which it is associated. A heavier emphasis is placed on external and environmental causes perceived as much more difficult to confront.

Biomechanical versus Inertial Information: Stable Individual Differences in Perception of Self-Rotation

ERIC Educational Resources Information Center

Bruggeman, Hugo; Piuneu, Vadzim S.; Rieser, John J.; Pick, Herbert L., Jr.

2009-01-01

When turning without vision or audition, people tend to perceive their locomotion as a change in heading relative to objects in the remembered surroundings. Such perception of self-rotation depends on sensitivity to information for movement from biomechanical activity of the locomotor system or from inertial activation of the vestibular and…

Direct comparison of the impact of head tracking, reverberation, and individualized head-related transfer functions on the spatial perception of a virtual speech source

NASA Technical Reports Server (NTRS)

Begault, D. R.; Wenzel, E. M.; Anderson, M. R.

2001-01-01

A study of sound localization performance was conducted using headphone-delivered virtual speech stimuli, rendered via HRTF-based acoustic auralization software and hardware, and blocked-meatus HRTF measurements. The independent variables were chosen to evaluate commonly held assumptions in the literature regarding improved localization: inclusion of head tracking, individualized HRTFs, and early and diffuse reflections. Significant effects were found for azimuth and elevation error, reversal rates, and externalization.

Space flight and changes in spatial orientation

NASA Technical Reports Server (NTRS)

Reschke, Millard F.; Bloomberg, Jacob J.; Harm, Deborah L.; Paloski, William H.

1992-01-01

From a sensory point of view, space flight represents a form of stimulus rearrangement requiring modification of established terrestrial response patterns through central reinterpretation. Evidence of sensory reinterpretation is manifested as postflight modifications of eye/head coordination, locomotor patterns, postural control strategies, and illusory perceptions of self or surround motion in conjunction with head movements. Under normal preflight conditions, the head is stabilized during locomotion, but immediately postflight reduced head stability, coupled with inappropriate eye/head coordination, results in modifications of gait. Postflight postural control exhibits increased dependence on vision which compensates for inappropriate interpretation of otolith and proprioceptive inputs. Eye movements compensatory for perceived self motion, rather than actual head movements have been observed postflight. Overall, the in-flight adaptive modification of head stabilization strategies, changes in head/eye coordination, illusionary motion, and postural control are maladaptive for a return to the terrestrial environment. Appropriate countermeasures for long-duration flights will rely on preflight adaptation and in-flight training.

Head Start Administrator and Teacher Perceptions of Parental Influence on Preschool Children's Nutrition Education

ERIC Educational Resources Information Center

Stage, Virginia C.; Wilkerson, Kristi; Hegde, Archana; Lisson, Sarah; Babatunde, Oyinlola Toyin; Goodell, L. Suzanne

2018-01-01

Parents play a significant role in molding their children's nutrition knowledge and behavior. The purpose of the present study was to explore parental influence on preschooler's nutrition education from the perspectives of North Carolina-based Head Start coordinators and teachers. Investigators conducted 63 in-depth, structured interviews with…

Investigating Maternal Self-Efficacy and Home Learning Environment of Families Enrolled in Head Start

ERIC Educational Resources Information Center

Bojczyk, Kathryn Elizabeth; Haverback, Heather Rogers; Pae, Hye K.

2018-01-01

The aim of this study was to examine the relationships between mothers' self-efficacy beliefs, their preschool children's home learning environments, and literacy skills. A sample of 112 mother-child dyads was recruited from Head Start centers in rural and urban communities. The measures included maternal self-efficacy and maternal perceptions of…

Perception of Chairpersons and Faculty concerning Roles, Descriptors, and Activities Important for Faculty Development and Departmental Vitality.

ERIC Educational Resources Information Center

Seagren, Alan T.; And Others

Activities and roles of department heads that can improve departmental and faculty effectiveness were investigated, along with dimensions associated with departmental leadership of chairpersons. In the first of two studies, department heads at four-year institutions were interviewed to identify views of existing conditions in higher education,…

The Influence of an Early Childhood Program on Parental Involvement: Perceptions of Former Head Start Parents

ERIC Educational Resources Information Center

Croft, Stacey

2017-01-01

A key component of effective early childhood programs is collaborative relationships between schools, families, and the community (Fiese, Eckert, & Spagnola, 2005). One of these early childhood programs, Head Start, stands out among the others in its efforts to work with children, families, and communities to promote parental involvement. Some…

Distinct Factors Associated with Head Start Mothers' Self-Report of Perceived Low Positive and High Negative Maternal Expressiveness

ERIC Educational Resources Information Center

Edwards, Nicole Megan

2014-01-01

Research Findings: There is growing acknowledgment of the need for parenting interventions to address early-onset behavior and emotional concerns. Favorable child outcomes have been linked to parents' responsiveness and positive expressiveness. Given the theoretical and empirical link between perceptions and actual behavior, Head Start mothers…

Career Development of English Female Head-Teachers: Influences, Decisions and Perceptions

ERIC Educational Resources Information Center

McKillop, Ewa; Moorosi, Pontso

2017-01-01

This paper presents findings from a study examining the career development experiences of female head-teachers in the south of England. Adapting a three-stage career model, the study examined different stages of the women's lives and careers in order to understand what encouraged and influenced them to become educational leaders and how their…

Comparing effects of "my anti-drug" and "above the influence" on campaign evaluations and marijuana-related perceptions.

PubMed

Comello, Maria Leonora G

2013-01-01

Two national campaigns--My Anti-Drug and Above the Influence--have been implemented to prevent youth substance use. Although Above the Influence was conceptualized as a major shift in messaging from My Anti-Drug, no studies have reported head-to-head tests of message effects on behavior-relevant outcomes. An experiment was conducted in which participants viewed ads from one of the campaigns and answered questions about ad appeal and emotional tone; campaign appeal; and marijuana-related beliefs. Compared to My Anti-Drug ads, Above the Influence ads were associated with more positive emotional tone and with lower perceptions of marijuana risk. Implications for message design and evaluation are discussed.

[Pediculosis capita in childhood: epidemiological and socio-medical results from screening of school beginners].

PubMed

Jahnke, C; Bauer, E; Feldmeier, H

2008-11-01

Although pediculosis capitis is the most frequent parasitosis in childhood, reliable data on its epidemiology and morbidity are scarce. In Germany population-based data do not exist. During the routine medical examination of 5-6-year-old pre-school children in Braunschweig city (n=1 890) the children were also examined for the presence of head lice and head lice-associated pathology. Visual inspection of five predilection sites was used to diagnose head lice infestation. Knowledge of careers on head lice infestation and disease perception were analysed using a standardised questionnaire. Socio-demographic variables of the households to which the children belonged were correlated to current or historical head lice infestation. Head lice infestation was diagnosed in 14 out of the 1 890 children (0.7%). Considering the low sensitivity of visual inspection the true prevalence should be higher by a factor 3 to 4. In addition, 5.6% of the children examined had suffered from a head lice infestation in the previous 12 months. This results in an incidence of 598 cases per 10,000 children aged 5 to 6 years per year. Households with a low educational level of the parents and without a background of migration were significantly more often affected by pediculosis capitis during the previous 12 months. The analysis of the questionnaires showed a rather low level of knowledge about pediculosis capitis, a tendency towards polypragmatic therapeutic approaches and partially aberrant reactions such as hysteria. The knowledge about pediculosis capitis was significantly lower in parents with a low educational level. Our study provides for the first time reliable data on the prevalence, incidence and disease perception of head lice infestation as well as concerning the knowledge parents have about this parasitic skin disease.

Smoking cessation treatment practices: recommendations for improved adoption on cardiology wards.

PubMed

Berndt, Nadine C; Bolman, Catherine; de Vries, Hein; Segaar, Dewi; van Boven, Irene; Lechner, Lilian

2013-01-01

Smoking cessation treatment practices described by the 5 A's (ask, advise, assess, assist, arrange) are not well applied at cardiology wards because of various reasons, such as a lack of time and appropriate skills of the nursing staff. Therefore, a simplified guideline proposing an ask-advise-refer (AAR) strategy was introduced in Dutch cardiac wards. This study aimed to identify factors that determine the intentions of cardiac ward heads in adopting the simplified AAR guideline, as ward heads are key decision makers in the adoption of new guidelines. Ward heads' perceptions of current smoking cessation practices at the cardiac ward were also investigated. A cross-sectional survey with written questionnaires was conducted among heads of cardiology wards throughout the Netherlands, of whom 117 (64%) responded. According to the heads of cardiac wards, smoking cessation practices by cardiologists and nurses were mostly limited to brief practices that are easy to conduct. Only a minority offered intensive counseling or arranged follow-up contact. Heads with strong intentions of adopting the AAR guideline differed significantly on motivational and organizational attributes and perceived more smoking cessation assistance by other health professionals than did heads with weak intentions of adopting. Positive attitudes, social support toward adoption, and perception of much assistance at the ward were significantly associated with increased intentions to adopt the AAR guideline. Brief smoking cessation practices are adequately performed at cardiac wards, but the most effective practices, offering assistance and arranging for follow-up, are less than optimal. The AAR guideline offers a more feasible approach for busy cardiology wards. To ensure successful adoption of this guideline, the heads of cardiac wards should be convinced of its advantages and be encouraged by a supportive work environment. Policies may also facilitate the adoption of the AAR guideline.

Visual-vestibular integration as a function of adaptation to space flight and return to Earth

NASA Technical Reports Server (NTRS)

Reschke, Millard R.; Bloomberg, Jacob J.; Harm, Deborah L.; Huebner, William P.; Krnavek, Jody M.; Paloski, William H.; Berthoz, Alan

1999-01-01

Research on perception and control of self-orientation and self-motion addresses interactions between action and perception . Self-orientation and self-motion, and the perception of that orientation and motion are required for and modified by goal-directed action. Detailed Supplementary Objective (DSO) 604 Operational Investigation-3 (OI-3) was designed to investigate the integrated coordination of head and eye movements within a structured environment where perception could modify responses and where response could be compensatory for perception. A full understanding of this coordination required definition of spatial orientation models for the microgravity environment encountered during spaceflight.

The use of a tactile interface to convey position and motion perceptions

NASA Technical Reports Server (NTRS)

Rupert, A. H.; Guedry, F. E.; Reschke, M. F.

1994-01-01

Under normal terrestrial conditions, perception of position and motion is determined by central nervous system integration of concordant and redundant information from multiple sensory channels (somatosensory, vestibular, visual), which collectively yield vertical perceptions. In the acceleration environment experienced by the pilots, the somatosensory and vestibular sensors frequently present false information concerning the direction of gravity. When presented with conflicting sensory information, it is normal for pilots to experience episodes of disorientation. We have developed a tactile interface that obtains vertical roll and pitch information from a gyro-stabilized attitude indicator and maps this information in a one-to-one correspondence onto the torso of the body using a matrix of vibrotactors. This enables the pilot to continuously maintain an awareness of aircraft attitude without reference to visual cues, utilizing a sensory channel that normally operates at the subconscious level. Although initially developed to improve pilot spatial awareness, this device has obvious applications to 1) simulation and training, 2) nonvisual tracking of targets, which can reduce the need for pilots to make head movements in the high-G environment of aerial combat, and 3) orientation in environments with minimal somatosensory cues (e.g., underwater) or gravitational cues (e.g., space).

Perceptions of Randomness: Why Three Heads Are Better than Four

ERIC Educational Resources Information Center

Hahn, Ulrike; Warren, Paul A.

2009-01-01

A long tradition of psychological research has lamented the systematic errors and biases in people's perception of the characteristics of sequences generated by a random mechanism such as a coin toss. It is proposed that once the likely nature of people's actual experience of such processes is taken into account, these "errors" and "biases"…

Barriers and Facilitators to Healthy Eating and Activity in Head Start Staff: An Opportunity for Worksite Wellness

ERIC Educational Resources Information Center

Hibbs-Shipp, Sarah K.; Milholland, Michelle; Bellows, Laura

2015-01-01

Background: Head Start (HS) staff are ideally positioned to promote healthy behaviors to over one million low-income children each year, however little is understood about their own health. Purpose: To conduct a needs assessment with HS staff to: 1) understand perceptions, barriers and motivators to healthful behaviors; and 2) ascertain interest…

Using "I Am Moving, I Am Learning" to Increase Quality Instruction in Head Start Classrooms

ERIC Educational Resources Information Center

Allar, Ishonté; Jones, Emily; Bulger, Sean

2018-01-01

Quality teacher-child interactions are characteristic of effective classrooms resulting in benefits for all children, but may be particularly important for children from low-income families. The purpose of this study was to explore the perception of Illinois Head Start teachers related to how "I am Moving, I am Learning" (IMIL) could…

Survivors' Experiences of Dysphagia-Related Services Following Head and Neck Cancer: Implications for Clinical Practice

ERIC Educational Resources Information Center

Nund, Rebecca L.; Ward, Elizabeth C.; Scarinci, Nerina A.; Cartmill, Bena; Kuipers, Pim; Porceddu, Sandro V.

2014-01-01

Background: It is known that people with dysphagia experience a number of negative consequences as a result of their swallowing difficulties following head and neck cancer management (HNC). However their perceptions and experiences of adjusting to dysphagia in the post-treatment phase, and the services received to assist this process, has not been…

Identification with School and Head Trauma: Parental Perceptions on Students' Experiences

ERIC Educational Resources Information Center

Jones, BreAnna; Robinson, Lindsay; Larwin, Karen H.

2015-01-01

In the United States 40% of all traumatic brain injuries (TBI) are in children under the age 14. This means a portion of the school age population is exposed to head injury every year. The effect this injury and experience can have on a child varies, but it is important for educators, counselors, and family to understand the psychosocial…

Judging sound rotation when listeners and sounds rotate: Sound source localization is a multisystem process.

PubMed

Yost, William A; Zhong, Xuan; Najam, Anbar

2015-11-01

In four experiments listeners were rotated or were stationary. Sounds came from a stationary loudspeaker or rotated from loudspeaker to loudspeaker around an azimuth array. When either sounds or listeners rotate the auditory cues used for sound source localization change, but in the everyday world listeners perceive sound rotation only when sounds rotate not when listeners rotate. In the everyday world sound source locations are referenced to positions in the environment (a world-centric reference system). The auditory cues for sound source location indicate locations relative to the head (a head-centric reference system), not locations relative to the world. This paper deals with a general hypothesis that the world-centric location of sound sources requires the auditory system to have information about auditory cues used for sound source location and cues about head position. The use of visual and vestibular information in determining rotating head position in sound rotation perception was investigated. The experiments show that sound rotation perception when sources and listeners rotate was based on acoustic, visual, and, perhaps, vestibular information. The findings are consistent with the general hypotheses and suggest that sound source localization is not based just on acoustics. It is a multisystem process.

Kinesthetic perceptions of earth- and body-fixed axes.

PubMed

Darling, W G; Hondzinski, J M

1999-06-01

The major purpose of this research was to determine whether kinesthetic/proprioceptive perceptions of the earth-fixed vertical axis are more accurate than perceptions of intrinsic axes. In one experiment, accuracy of alignment of the forearm to earth-fixed vertical and head- and trunk-longitudinal axes by seven blindfolded subjects was compared in four tasks: (1) Earth-Arm--arm (humerus) orientation was manipulated by the experimenter; subjects aligned the forearm parallel to the vertical axis, which was also aligned with the head and trunk longitudinal axis; (2) Head--head, trunk, and upper-limb orientations were manipulated by the experimenter, subjects aligned the forearm parallel to the longitudinal axis of the head using only elbow flexion/extension and shoulder internal/external rotation; (3) Trunk--same as (2), except that subjects aligned the forearm parallel to the trunk-longitudinal axis; (4) Earth--same as (2), except that subjects aligned the forearm parallel to the earth-fixed vertical. Head, trunk, and gravitational axes were never parallel in tasks 2, 3, and 4 so that subjects could not simultaneously match their forearm to all three axes. The results showed that the errors for alignment of the forearm with the earth-fixed vertical were lower than for the trunk- and head-longitudinal axes. Furthermore, errors in the Earth condition were less dependent on alterations of the head and trunk orientation than in the Head and Trunk conditions. These data strongly suggest that the earth-fixed vertical is used as one axis for the kinesthetic sensory coordinate system that specifies upper-limb orientation at the perceptual level. We also examined the effects of varying gravitational torques at the elbow and shoulder on the accuracy of forearm alignment to earth-fixed axes. Adding a 450 g load to the forearm to increase gravitational torques when the forearm is not vertical did not improve the accuracy of forearm alignment with the vertical. Furthermore, adding small, variably sized loads (between which the subjects could not distinguish at the perceptual level) to the forearm just proximal to the wrist produced similar errors in aligning the forearm with the vertical and horizontal. Forearm-positioning errors were not correlated with the size of the load, as would be expected if gravitational torques affected forearm-position sense. We conclude that gravitational torques exerted about the shoulder and elbow do not make significant contributions to sensing forearm-orientation relative to earth-fixed axes when the upper-limb segments are not constrained by external supports.

Head Pose Estimation Using Multilinear Subspace Analysis for Robot Human Awareness

NASA Technical Reports Server (NTRS)

Ivanov, Tonislav; Matthies, Larry; Vasilescu, M. Alex O.

2009-01-01

Mobile robots, operating in unconstrained indoor and outdoor environments, would benefit in many ways from perception of the human awareness around them. Knowledge of people's head pose and gaze directions would enable the robot to deduce which people are aware of the its presence, and to predict future motions of the people for better path planning. To make such inferences, requires estimating head pose on facial images that are combination of multiple varying factors, such as identity, appearance, head pose, and illumination. By applying multilinear algebra, the algebra of higher-order tensors, we can separate these factors and estimate head pose regardless of subject's identity or image conditions. Furthermore, we can automatically handle uncertainty in the size of the face and its location. We demonstrate a pipeline of on-the-move detection of pedestrians with a robot stereo vision system, segmentation of the head, and head pose estimation in cluttered urban street scenes.

Modeling the Overalternating Bias with an Asymmetric Entropy Measure

PubMed Central

Gronchi, Giorgio; Raglianti, Marco; Noventa, Stefano; Lazzeri, Alessandro; Guazzini, Andrea

2016-01-01

Psychological research has found that human perception of randomness is biased. In particular, people consistently show the overalternating bias: they rate binary sequences of symbols (such as Heads and Tails in coin flipping) with an excess of alternation as more random than prescribed by the normative criteria of Shannon's entropy. Within data mining for medical applications, Marcellin proposed an asymmetric measure of entropy that can be ideal to account for such bias and to quantify subjective randomness. We fitted Marcellin's entropy and Renyi's entropy (a generalized form of uncertainty measure comprising many different kinds of entropies) to experimental data found in the literature with the Differential Evolution algorithm. We observed a better fit for Marcellin's entropy compared to Renyi's entropy. The fitted asymmetric entropy measure also showed good predictive properties when applied to different datasets of randomness-related tasks. We concluded that Marcellin's entropy can be a parsimonious and effective measure of subjective randomness that can be useful in psychological research about randomness perception. PMID:27458418

Neural Integration of Information Specifying Human Structure from Form, Motion, and Depth

PubMed Central

Jackson, Stuart; Blake, Randolph

2010-01-01

Recent computational models of biological motion perception operate on ambiguous two-dimensional representations of the body (e.g., snapshots, posture templates) and contain no explicit means for disambiguating the three-dimensional orientation of a perceived human figure. Are there neural mechanisms in the visual system that represent a moving human figure’s orientation in three dimensions? To isolate and characterize the neural mechanisms mediating perception of biological motion, we used an adaptation paradigm together with bistable point-light (PL) animations whose perceived direction of heading fluctuates over time. After exposure to a PL walker with a particular stereoscopically defined heading direction, observers experienced a consistent aftereffect: a bistable PL walker, which could be perceived in the adapted orientation or reversed in depth, was perceived predominantly reversed in depth. A phase-scrambled adaptor produced no aftereffect, yet when adapting and test walkers differed in size or appeared on opposite sides of fixation aftereffects did occur. Thus, this heading direction aftereffect cannot be explained by local, disparity-specific motion adaptation, and the properties of scale and position invariance imply higher-level origins of neural adaptation. Nor is disparity essential for producing adaptation: when suspended on top of a stereoscopically defined, rotating globe, a context-disambiguated “globetrotter” was sufficient to bias the bistable walker’s direction, as were full-body adaptors. In sum, these results imply that the neural signals supporting biomotion perception integrate information on the form, motion, and three-dimensional depth orientation of the moving human figure. Models of biomotion perception should incorporate mechanisms to disambiguate depth ambiguities in two-dimensional body representations. PMID:20089892

Altered attentional and perceptual processes as indexed by N170 during gaze perception in schizophrenia: Relationship with perceived threat and paranoid delusions.

PubMed

Tso, Ivy F; Calwas, Anita M; Chun, Jinsoo; Mueller, Savanna A; Taylor, Stephan F; Deldin, Patricia J

2015-08-01

Using gaze information to orient attention and guide behavior is critical to social adaptation. Previous studies have suggested that abnormal gaze perception in schizophrenia (SCZ) may originate in abnormal early attentional and perceptual processes and may be related to paranoid symptoms. Using event-related brain potentials (ERPs), this study investigated altered early attentional and perceptual processes during gaze perception and their relationship to paranoid delusions in SCZ. Twenty-eight individuals with SCZ or schizoaffective disorder and 32 demographically matched healthy controls (HCs) completed a gaze-discrimination task with face stimuli varying in gaze direction (direct, averted), head orientation (forward, deviated), and emotion (neutral, fearful). ERPs were recorded during the task. Participants rated experienced threat from each face after the task. Participants with SCZ were as accurate as, though slower than, HCs on the task. Participants with SCZ displayed enlarged N170 responses over the left hemisphere to averted gaze presented in fearful relative to neutral faces, indicating a heightened encoding sensitivity to faces signaling external threat. This abnormality was correlated with increased perceived threat and paranoid delusions. Participants with SCZ also showed a reduction of N170 modulation by head orientation (normally increased amplitude to deviated faces relative to forward faces), suggesting less integration of contextual cues of head orientation in gaze perception. The psychophysiological deviations observed during gaze discrimination in SCZ underscore the role of early attentional and perceptual abnormalities in social information processing and paranoid symptoms of SCZ. (c) 2015 APA, all rights reserved).

Use of mobile device technology to continuously collect patient-reported symptoms during radiation therapy for head and neck cancer: A prospective feasibility study.

PubMed

Falchook, Aaron D; Tracton, Gregg; Stravers, Lori; Fleming, Mary E; Snavely, Anna C; Noe, Jeanne F; Hayes, David N; Grilley-Olson, Juneko E; Weiss, Jared M; Reeve, Bryce B; Basch, Ethan M; Chera, Bhishamjit S

2016-01-01

Accurate assessment of toxicity allows for timely delivery of supportive measures during radiation therapy for head and neck cancer. The current paradigm requires weekly evaluation of patients by a provider. The purpose of this study is to evaluate the feasibility of monitoring patient reported symptoms via mobile devices. We developed a mobile application for patients to report symptoms in 5 domains using validated questions. Patients were asked to report symptoms using a mobile device once daily during treatment or more often as needed. Clinicians reviewed patient-reported symptoms during weekly symptom management visits and patients completed surveys regarding perceptions of the utility of the mobile application. The primary outcome measure was patient compliance with mobile device reporting. Compliance is defined as number of days with a symptom report divided by number of days on study. There were 921 symptom reports collected from 22 patients during treatment. Median reporting compliance was 71% (interquartile range, 45%-80%). Median number of reports submitted per patient was 34 (interquartile range, 21-53). Median number of reports submitted by patients per week was similar throughout radiation therapy and there was significant reporting during nonclinic hours. Patients reported high satisfaction with the use of mobile devices to report symptoms. A substantial percentage of patients used mobile devices to continuously report symptoms throughout a course of radiation therapy for head and neck cancer. Future studies should evaluate the impact of mobile device symptom reporting on improving patient outcomes.

Parent Self-Efficacy as an Influencing Factor in Parent Participation in Homework Activities: Perceptions of Head Start Parents and Educators

ERIC Educational Resources Information Center

Olivas, Cynthia

2013-01-01

Purpose: The purpose of the study was to explore the perceptions of parents and educators toward the role parents assumed in supporting preschool children academically, and to assess parents' self-efficacy and its influence on parental involvement in preschoolers' homework tasks. A further purpose was to compare parents' perceived self-efficacy…

Perceptions of the Dilemma--Order versus Freedom at Managing Faculty: A Literature Review

ERIC Educational Resources Information Center

Karaferye, Figen; Agaoglu, Esmahan

2017-01-01

This study aims to examine the perceptions of the middle management (deans and heads of departments) and academicians on the dilemma order versus freedom at faculty management. It discusses how this dilemma is seen at an operational level and how it can be managed at university where both parties--with a managerial role or not--are…

The Effects of Visual Beats on Prosodic Prominence: Acoustic Analyses, Auditory Perception and Visual Perception

ERIC Educational Resources Information Center

Krahmer, Emiel; Swerts, Marc

2007-01-01

Speakers employ acoustic cues (pitch accents) to indicate that a word is important, but may also use visual cues (beat gestures, head nods, eyebrow movements) for this purpose. Even though these acoustic and visual cues are related, the exact nature of this relationship is far from well understood. We investigate whether producing a visual beat…

Relating Difficulty in School Mathematics to Nature of Mathematics: Perception of High School Students from Kerala

ERIC Educational Resources Information Center

Gafoor, Kunnathodi Abdul; Sarabi, M. K.

2015-01-01

This study relates factors in nature of Mathematics and its teaching learning to student difficulties for diverse mathematics tasks. Descriptive survey was done on a sample of 300 high school students in Kerala with a questionnaire on difficulties in learning. Student perception of difficulty on 26 types of tasks, under five heads that students…

Using Visible Speech to Train Perception and Production of Speech for Individuals with Hearing Loss.

ERIC Educational Resources Information Center

Massaro, Dominic W.; Light, Joanna

2004-01-01

The main goal of this study was to implement a computer-animated talking head, Baldi, as a language tutor for speech perception and production for individuals with hearing loss. Baldi can speak slowly; illustrate articulation by making the skin transparent to reveal the tongue, teeth, and palate; and show supplementary articulatory features, such…

Head-turning asymmetries during kissing and their association with lateral preference.

PubMed

Ocklenburg, Sebastian; Güntürkün, Onur

2009-01-01

A head-turning bias to the right side is one of the earliest functional asymmetries in human development and is already present during the final weeks of gestation. To test whether head-turning preference is related to other lateral preferences in adults, kissing behaviour of participants towards a symmetrical doll was observed to assess their spontaneous head-turning preference. Additionally, participants' individual handedness, footedness, and eye preference were determined using questionnaires. A significant difference in handedness and footedness, but not eye preference, was found between left- and right-kissers, with right-kissers showing a stronger right-sided bias than left-kissers. These results support the assumption that the head-turning bias in humans may be able to induce or enhance other asymmetries of perception and action.

Illusion in reality: visual perception in displays

NASA Astrophysics Data System (ADS)

Kaufman, Lloyd; Kaufman, James H.

2001-06-01

Research into visual perception ultimately affects display design. Advance in display technology affects, in turn, our study of perception. Although this statement is too general to provide controversy, this paper present a real-life example that may prompt display engineers to make greater use of basic knowledge of visual perception, and encourage those who study perception to track more closely leading edge display technology. Our real-life example deals with an ancient problem, the moon illusion: why does the horizon moon appear so large while the elevated moon look so small. This was a puzzle for many centuries. Physical explanations, such as refraction by the atmosphere, are incorrect. The difference in apparent size may be classified as a misperception, so the answer must lie in the general principles of visual perception. The factors underlying the moon illusion must be the same factors as those that enable us to perceive the sizes of ordinary objects in visual space. Progress toward solving the problem has been irregular, since methods for actually measuring the illusion under a wide range of conditions were lacking. An advance in display technology made possible a serious and methodologically controlled study of the illusion. This technology was the first heads-up display. In this paper we will describe how the heads-up display concept made it possible to test several competing theories of the moon illusion, and how it led to an explanation that stood for nearly 40 years. We also consider the criticisms of that explanation and how the optics of the heads-up display also played a role in providing data for the critics. Finally, we will describe our own advance on the original methodology. This advance was motivated by previously unrelated principles of space perception. We used a stereoscopic heads up display to test alternative hypothesis about the illusion and to discrimate between two classes of mutually contradictory theories. At its core, the explanation for the moon illusion has implications for the design of virtual reality displays. Howe do we scale disparity at great distances to reflect depth between points at those distances. We conjecture that one yardstick involved in that scaling is provided by oculomotor cues operating at near distances. Without the presence of such a yardstick it is not possible to account for depth at long distances. As we shall explain, size and depth constancy should both fail in virtual reality display where all of the visual information is optically in one plane. We suggest ways to study this problem, and also means by which displays may be designed to present information at different optical distances.

The neural encoding of self-generated and externally applied movement: implications for the perception of self-motion and spatial memory

PubMed Central

Cullen, Kathleen E.

2014-01-01

The vestibular system is vital for maintaining an accurate representation of self-motion. As one moves (or is moved) toward a new place in the environment, signals from the vestibular sensors are relayed to higher-order centers. It is generally assumed the vestibular system provides a veridical representation of head motion to these centers for the perception of self-motion and spatial memory. In support of this idea, evidence from lesion studies suggests that vestibular inputs are required for the directional tuning of head direction cells in the limbic system as well as neurons in areas of multimodal association cortex. However, recent investigations in monkeys and mice challenge the notion that early vestibular pathways encode an absolute representation of head motion. Instead, processing at the first central stage is inherently multimodal. This minireview highlights recent progress that has been made towards understanding how the brain processes and interprets self-motion signals encoded by the vestibular otoliths and semicircular canals during everyday life. The following interrelated questions are considered. What information is available to the higher-order centers that contribute to self-motion perception? How do we distinguish between our own self-generated movements and those of the external world? And lastly, what are the implications of differences in the processing of these active vs. passive movements for spatial memory? PMID:24454282

Effects of Peripheral Eccentricity and Head Orientation on Gaze Discrimination.

PubMed

Palanica, Adam; Itier, Roxane J

2014-01-01

Visual search tasks support a special role for direct gaze in human cognition, while classic gaze judgment tasks suggest the congruency between head orientation and gaze direction plays a central role in gaze perception. Moreover, whether gaze direction can be accurately discriminated in the periphery using covert attention is unknown. In the present study, individual faces in frontal and in deviated head orientations with a direct or an averted gaze were flashed for 150 ms across the visual field; participants focused on a centred fixation while judging the gaze direction. Gaze discrimination speed and accuracy varied with head orientation and eccentricity. The limit of accurate gaze discrimination was less than ±6° eccentricity. Response times suggested a processing facilitation for direct gaze in fovea, irrespective of head orientation, however, by ±3° eccentricity, head orientation started biasing gaze judgments, and this bias increased with eccentricity. Results also suggested a special processing of frontal heads with direct gaze in central vision, rather than a general congruency effect between eye and head cues. Thus, while both head and eye cues contribute to gaze discrimination, their role differs with eccentricity.

Austerite et gestion dans les universites quebecoises: une analyse des perceptions de directeurs de departement=Austerity and Administration in Quebec's Universities: An Analysis of Department Heads' Perceptions.

ERIC Educational Resources Information Center

Crespo, Manuel; And Others

1986-01-01

A survey of 25 Quebec university department chairmen concerning the management of budgetary austerity found that administrative responses are generally perceived as reactionary and short-sighted, but long-term solutions proposed by chairmen are based on conflicting views of the overall role of the institution. (MSE)

A Model of Human Orientation and Self Motion Perception during Body Acceleration: The Orientation Modeling System

DTIC Science & Technology

2016-09-28

previous research and modeling results. The OMS and Perception Toolbox were used to perform a case study of an F18 mishap. Model results imply that...request documents from DTIC. Change of Address Organizations receiving reports from the U.S. Army Aeromedical Research Laboratory on automatic...54  Coriolis head movement during a coordinated turn. .............................................55  Case Study

Air Vehicle Technology Integration Program (AVTIP). Delivery Order 0054: Opportune Landing Site (OLS) Critical Experiment

DTIC Science & Technology

2008-04-01

suitability would result in safer landings and reduced maintenance costs associated with an intended area of operations 2.1.2. Concept of... cost , integration, logistics, ownership, performance, schedule, and user perception. Criteria were developed for three timeframes—reflecting the end...analysis.. Changed runway finder back to six cardinal headings or user specified headings. Added NASA ACCA cloud recognition filter. Added switches for

The applicability of a computer model for predicting head injury incurred during actual motor vehicle collisions.

PubMed

Moran, Stephan G; Key, Jason S; McGwin, Gerald; Keeley, Jason W; Davidson, James S; Rue, Loring W

2004-07-01

Head injury is a significant cause of both morbidity and mortality. Motor vehicle collisions (MVCs) are the most common source of head injury in the United States. No studies have conclusively determined the applicability of computer models for accurate prediction of head injuries sustained in actual MVCs. This study sought to determine the applicability of such models for predicting head injuries sustained by MVC occupants. The Crash Injury Research and Engineering Network (CIREN) database was queried for restrained drivers who sustained a head injury. These collisions were modeled using occupant dynamic modeling (MADYMO) software, and head injury scores were generated. The computer-generated head injury scores then were evaluated with respect to the actual head injuries sustained by the occupants to determine the applicability of MADYMO computer modeling for predicting head injury. Five occupants meeting the selection criteria for the study were selected from the CIREN database. The head injury scores generated by MADYMO were lower than expected given the actual injuries sustained. In only one case did the computer analysis predict a head injury of a severity similar to that actually sustained by the occupant. Although computer modeling accurately simulates experimental crash tests, it may not be applicable for predicting head injury in actual MVCs. Many complicating factors surrounding actual MVCs make accurate computer modeling difficult. Future modeling efforts should consider variables such as age of the occupant and should account for a wider variety of crash scenarios.

Heading Tuning in Macaque Area V6.

PubMed

Fan, Reuben H; Liu, Sheng; DeAngelis, Gregory C; Angelaki, Dora E

2015-12-16

Cortical areas, such as the dorsal subdivision of the medial superior temporal area (MSTd) and the ventral intraparietal area (VIP), have been shown to integrate visual and vestibular self-motion signals. Area V6 is interconnected with areas MSTd and VIP, allowing for the possibility that V6 also integrates visual and vestibular self-motion cues. An alternative hypothesis in the literature is that V6 does not use these sensory signals to compute heading but instead discounts self-motion signals to represent object motion. However, the responses of V6 neurons to visual and vestibular self-motion cues have never been studied, thus leaving the functional roles of V6 unclear. We used a virtual reality system to examine the 3D heading tuning of macaque V6 neurons in response to optic flow and inertial motion stimuli. We found that the majority of V6 neurons are selective for heading defined by optic flow. However, unlike areas MSTd and VIP, V6 neurons are almost universally unresponsive to inertial motion in the absence of optic flow. We also explored the spatial reference frames of heading signals in V6 by measuring heading tuning for different eye positions, and we found that the visual heading tuning of most V6 cells was eye-centered. Similar to areas MSTd and VIP, the population of V6 neurons was best able to discriminate small variations in heading around forward and backward headings. Our findings support the idea that V6 is involved primarily in processing visual motion signals and does not appear to play a role in visual-vestibular integration for self-motion perception. To understand how we successfully navigate our world, it is important to understand which parts of the brain process cues used to perceive our direction of self-motion (i.e., heading). Cortical area V6 has been implicated in heading computations based on human neuroimaging data, but direct measurements of heading selectivity in individual V6 neurons have been lacking. We provide the first demonstration that V6 neurons carry 3D visual heading signals, which are represented in an eye-centered reference frame. In contrast, we found almost no evidence for vestibular heading signals in V6, indicating that V6 is unlikely to contribute to multisensory integration of heading signals, unlike other cortical areas. These findings provide important constraints on the roles of V6 in self-motion perception. Copyright © 2015 the authors 0270-6474/15/3516303-12$15.00/0.

The Use of Music in Labor: Pain Perception

DTIC Science & Technology

1991-01-01

AD-A267 985liiiiiii ii ii iii lillinl lJtlflllllIi 1\\k . Music in Labor DTIC43.t ELECTE wN AUGt 1 1993UThe Use of Music in Labor: A C1 Pain...Perception Kathy Jo Keever Patricia A. Shepherd AFIT/Georgetown University School of Nursing Running head: MUSIC IN LABOR Ap9i" "r85T16x• ~ ;u~c r~eca _W...FUNDING NUMBERS The Use of Music in Labor: Pain Perception 6. AUTHOR(S) 1st Lt Kathy Keever Capt Patricia Shepherd PERFORMING ORGANIZATION NAME(S) AND

IMPLEMENTING AN ATTACHMENT-BASED PARENTING INTERVENTION WITHIN HOME-BASED EARLY HEAD START: HOME-VISITORS' PERCEPTIONS AND EXPERIENCES.

PubMed

West, Allison L; Aparicio, Elizabeth M; Berlin, Lisa J; Jones Harden, Brenda

2017-07-01

Implementation of evidence-based interventions in "real-world" settings is enhanced when front-line staff view the intervention as acceptable, appropriate, and feasible. This qualitative study addresses Early Head Start (EHS) home visitors' perceptions and experiences of an evidence-based parenting intervention, the Attachment and Biobehavioral Catch-up program (M. Dozier, O. Lindhiem, & J. Ackerman, 2005), when added to EHS services as usual within the context of a research-practice partnership. Thematic analysis of in-depth, qualitative interviews indicates that home visitors experienced the intervention as positive and helpful for EHS families. Some challenges included scheduling and uncertainty regarding the goals of the intervention. Concerns over participation in the research centered on information exchange, confidentiality, and time limitations. © 2017 Michigan Association for Infant Mental Health.

Household perceptions towards a redistributive policy across health insurance funds in Tanzania.

PubMed

Chomi, Eunice N; Mujinja, Phares G M; Hansen, Kristian; Kiwara, Angwara D; Enemark, Ulrika

2015-03-15

The Tanzanian health insurance system comprises multiple health insurance funds targeting different population groups but which operate in parallel, with no mechanisms for redistribution across the funds. Establishing such redistributive mechanisms requires public support, which is grounded on the level of solidarity within the country. The aim of this paper is to analyse the perceptions of CHF, NHIF and non-member households towards cross-subsidisation of the poor as an indication of the level of solidarity and acceptance of redistributive mechanisms. This study analyses data collected from a survey of 695 households relating to perceptions of household heads towards cross-subsidisation of the poor to enable them to access health services. Kruskal-Wallis test is used to compare perceptions by membership status. Generalized ordinal logistic regression models are used to identify factors associated with support for cross-subsidisation of the poor. Compared to CHF and NHIF households, non-member households expressed the highest support for subsidised CHF membership for the poor. The odds of expressing support for subsidised CHF membership are higher for NHIF households and non-member households, households that are wealthier, whose household heads have lower education levels, and have sick members. The majority of households support a partial rather than fully subsidised CHF membership for the poor and there were no significant differences by membership status. The odds of expressing willingness to contribute towards subsidised CHF membership are higher for households that are wealthier, with young household heads and have confidence in scheme management. The majority may support a redistributive policy, but there are indications that this support and willingness to contribute to its achievement are influenced by the perceived benefits, amount of subsidy considered, and trust in scheme management. These present important issues for consideration when designing redistributive policies.

Remote vs. head-mounted eye-tracking: a comparison using radiologists reading mammograms

NASA Astrophysics Data System (ADS)

Mello-Thoms, Claudia; Gur, David

2007-03-01

Eye position monitoring has been used for decades in Radiology in order to determine how radiologists interpret medical images. Using these devices several discoveries about the perception/decision making process have been made, such as the importance of comparisons of perceived abnormalities with selected areas of the background, the likelihood that a true lesion will attract visual attention early in the reading process, and the finding that most misses attract prolonged visual dwell, often comparable to dwell in the location of reported lesions. However, eye position tracking is a cumbersome process, which often requires the observer to wear a helmet gear which contains the eye tracker per se and a magnetic head tracker, which allows for the computation of head position. Observers tend to complain of fatigue after wearing the gear for a prolonged time. Recently, with the advances made to remote eye-tracking, the use of head-mounted systems seemed destined to become a thing of the past. In this study we evaluated a remote eye tracking system, and compared it to a head-mounted system, as radiologists read a case set of one-view mammograms on a high-resolution display. We compared visual search parameters between the two systems, such as time to hit the location of the lesion for the first time, amount of dwell time in the location of the lesion, total time analyzing the image, etc. We also evaluated the observers' impressions of both systems, and what their perceptions were of the restrictions of each system.

Effects of hair sprays on colour perception: a hyperspectral imaging approach to shine and chroma on heads.

PubMed

Puccetti, G; Thompson, W

2017-04-01

Hair sprays apply fixative ingredients to provide hold to a hair style as well as weather resistance and optical properties such as shine. Generally, sprays distribute fine particles containing polymeric ingredients to form a thin film on the surface of hair. Different hair types require different strengths of the formed deposit on the hair surface. The present study shows how sprays also alter the visibility of the hair colour by altering the surface topology of the hair fibres. Hyperspectral imaging is used to map spectral characteristics of hair on mannequins and panelists over the curvature of heads. Spectral and spatial characteristics are measured before and after hair spray applications. The hair surface is imaged by SEM to visualize the degree of cuticle coverage. Finally, the perception of hair colour was evaluated on red-coloured mannequins by consumer questionnaire. Hair sprays deposit different degrees of fixatives, which lead to a progressive leveling of the cuticle natural tilt angle with respect to the fibre axis. As a result, shine is progressively shifting towards the region of hair colour visibility and decreases the perceived colour of hair seen by consumers. Lighter sprays show thinner film formation on the hair surface and less of a shine shift than strong hold hair sprays. Hair sprays are generally employed for hair style hold and weather resistance and considered without effect on hair colour. Our approach shows that spray-deposited films can affect colour perception by altering the microstructure of the hair surface. Thin films deposited on the hair fibre surface can partially fill gaps between cuticles, which reduces the cuticle natural angle. This partial erasure results in a angle shift of the shine regions towards the angle of internal reflection, thus decreasing the perceived hair colour regions as experienced by a group of consumers. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

[Traumatic lesion of the optic nerve head by flying fish: a case report].

PubMed

Martin, M; Orgül, S; Robertson, A; Flammer, J

2004-05-01

Traumatic lesion to the optic nerve often leads to severe and persistent functional loss. A male patient was transferred to our hospital from the University Eye Clinic of Guadeloupe 5 days after ocular injury caused by a flying fish. Visual function was light perception. The anterior part of the eye and retina were unremarkable. A computer tomography disclosed a fracture of the sphenoid sinus, with a little bone fragment (DD: foreign body) located close to the optic nerve. Therapy had been started with Aminopenicillin combined with clavulan acid (Augmentin) i. v., 500 ml methylprednisolone (Solumedrol) i. v., lysine-acetyl salicylate (Aspegic) and topical application of dexamethasone combined with neomycin/polymyxin B (Maxitrol). We continued this therapy and intensified it by adding nimodipine (Nimotop) 30 1-1-1 and acetazolamide retard (Diamox sustet) 1-0-1. Unfortunately visual function did not recover under therapy. Traumatic lesions of the optic nerve head, especially when due to axial or tangential forces, can lead to severe and irreversible functional loss. Severe traumatic lesions, even bone fractures induced by flying fish are not a seldom encounter in the Caribbean Sea.

The Effect of Visual Experience on Perceived Haptic Verticality When Tilted in the Roll Plane

PubMed Central

Cuturi, Luigi F.; Gori, Monica

2017-01-01

The orientation of the body in space can influence perception of verticality leading sometimes to biases consistent with priors peaked at the most common head and body orientation, that is upright. In this study, we investigate haptic perception of verticality in sighted individuals and early and late blind adults when tilted counterclockwise in the roll plane. Participants were asked to perform a stimulus orientation discrimination task with their body tilted to their left ear side 90° relative to gravity. Stimuli were presented by using a motorized haptic bar. In order to test whether different reference frames relative to the head influenced perception of verticality, we varied the position of the stimulus on the body longitudinal axis. Depending on the stimulus position sighted participants tended to have biases away or toward their body tilt. Visually impaired individuals instead show a different pattern of verticality estimations. A bias toward head and body tilt (i.e., Aubert effect) was observed in late blind individuals. Interestingly, no strong biases were observed in early blind individuals. Overall, these results posit visual sensory information to be fundamental in influencing the haptic readout of proprioceptive and vestibular information about body orientation relative to gravity. The acquisition of an idiotropic vector signaling the upright might take place through vision during development. Regarding early blind individuals, independent spatial navigation experience likely enhanced by echolocation behavior might have a role in such acquisition. In the case of participants with late onset blindness, early experience of vision might lead them to anchor their visually acquired priors to the haptic modality with no disambiguation between head and body references as observed in sighted individuals (Fraser et al., 2015). With our study, we aim to investigate haptic perception of gravity direction in unusual body tilts when vision is absent due to visual impairment. Insofar, our findings throw light on the influence of proprioceptive/vestibular sensory information on haptic perceived verticality in blind individuals showing how this phenomenon is affected by visual experience. PMID:29270109

Virtual reality as a human factors design analysis tool: Macro-ergonomic application validation and assessment of the Space Station Freedom payload control area

NASA Technical Reports Server (NTRS)

Hale, Joseph P.

1994-01-01

A virtual reality (VR) Applications Program has been under development at MSFC since 1989. Its objectives are to develop, assess, validate, and utilize VR in hardware development, operations development and support, missions operations training, and science training. A variety of activities are under way within many of these areas. One ongoing macro-ergonomic application of VR relates to the design of the Space Station Freedom Payload Control Area (PCA), the control room from which onboard payload operations are managed. Several preliminary conceptual PCA layouts have been developed and modeled in VR. Various managers and potential end users have virtually 'entered' these rooms and provided valuable feedback. Before VR can be used with confidence in a particular application, it must be validated, or calibrated, for that class of applications. Two associated validation studies for macro-ergonomic applications are under way to help characterize possible distortions of filtering of relevant perceptions in a virtual world. In both studies, existing control rooms and their 'virtual counterparts will be empirically compared using distance and heading estimations to objects and subjective assessments. Approaches and findings of the PCA activities and details of the studies are presented.

Effects of Parkinson’s disease on optic flow perception for heading direction during navigation

PubMed Central

Wagenaar, Robert C.; Young, Daniel; Saltzman, Elliot L.; Ren, Xiaolin; Neargarder, Sandy; Cronin-Golomb, Alice

2015-01-01

Visuoperceptual disorders have been identified in individuals with Parkinson’s disease (PD) and may affect the perception of optic flow for heading direction during navigation. Studies in healthy subjects have confirmed that heading direction can be determined by equalizing the optic flow speed (OS) between visual fields. The present study investigated the effects of PD on the use of optic flow for heading direction, walking parameters, and interlimb coordination during navigation, examining the contributions of OS and spatial frequency (dot density). Twelve individuals with PD without dementia, 18 age-matched normal control adults (NC), and 23 young control adults (YC) walked through a virtual hallway at about 0.8 m/s. The hallway was created by random dots on side walls. Three levels of OS (0.8, 1.2, and 1.8 m/s) and dot density (1, 2, and 3 dots/m2) were presented on one wall while on the other wall, OS and dot density were fixed at 0.8 m/s and 3 dots/m2, respectively. Three-dimensional kinematic data were collected, and lateral drift, walking speed, stride frequency and length, and frequency, and phase relations between arms and legs were calculated. A significant linear effect was observed on lateral drift to the wall with lower OS for YC and NC, but not for PD. Compared to YC and NC, PD veered more to the left under OS and dot density conditions. The results suggest that healthy adults perceive optic flow for heading direction. Heading direction in PD may be more affected by the asymmetry of dopamine levels between the hemispheres and by motor lateralization as indexed by handedness. PMID:24510351

The Subjective Visual Vertical and the Subjective Haptic Vertical Access Different Gravity Estimates.

PubMed

Fraser, Lindsey E; Makooie, Bobbak; Harris, Laurence R

2015-01-01

The subjective visual vertical (SVV) and the subjective haptic vertical (SHV) both claim to probe the underlying perception of gravity. However, when the body is roll tilted these two measures evoke different patterns of errors with SVV generally becoming biased towards the body (A-effect, named for its discoverer, Hermann Rudolph Aubert) and SHV remaining accurate or becoming biased away from the body (E-effect, short for Entgegengesetzt-effect, meaning "opposite", i.e., opposite to the A-effect). We compared the two methods in a series of five experiments and provide evidence that the two measures access two different but related estimates of gravitational vertical. Experiment 1 compared SVV and SHV across three levels of whole-body tilt and found that SVV showed an A-effect at larger tilts while SHV was accurate. Experiment 2 found that tilting either the head or the trunk independently produced an A-effect in SVV while SHV remained accurate when the head was tilted on an upright body but showed an A-effect when the body was tilted below an upright head. Experiment 3 repeated these head/body configurations in the presence of vestibular noise induced by using disruptive galvanic vestibular stimulation (dGVS). dGVS abolished both SVV and SHV A-effects while evoking a massive E-effect in the SHV head tilt condition. Experiments 4 and 5 show that SVV and SHV do not combine in an optimally statistical fashion, but when vibration is applied to the dorsal neck muscles, integration becomes optimal. Overall our results suggest that SVV and SHV access distinct underlying gravity percepts based primarily on head and body position information respectively, consistent with a model proposed by Clemens and colleagues.

Head temperature modulates thermal behavior in the cold in humans

PubMed Central

Mündel, Toby; Raman, Aaron; Schlader, Zachary J.

2016-01-01

ABSTRACT We tested the hypothesis that skin temperature, specifically of the head, is capable of modulating thermal behavior during exercise in the cold. Following familiarization 8 young, healthy, recreationally active males completed 3 trials, each consisting of 30 minutes of self-paced cycle ergometry in 6°C. Participants were instructed to control their exercise work rate to achieve and maintain thermal comfort. On one occasion participants wore only shorts and shoes (Control) and on the 2 other occasions their head was either warmed (Warming) or cooled (Cooling). Work rate, rate of metabolic heat production, thermal perceptions, rectal, mean weighted skin and head temperatures were measured. Exercise work rate was reduced during Warming and augmented during Cooling after the first and second minutes of exercise, respectively (P ≤ 0.04), with the rate of metabolic heat production mirroring work rate. At this early stage of exercise (≤5 min) the changes over time for rectal temperature were negligible and similar (0.1 ± 0.1°C, P = 0.51), while the decrease in mean skin temperature was not different between all trials (1.7 ± 0.6°C, P = 0.13). Mean head temperature was either decreased (Control: 1.5 ± 1.1°C, Cooling: 2.9 ± 0.8°C, both P < 0.01) or increased (Warming: 1.7 ± 0.9°C, P < 0.01). Head thermal perception was warmer and more comfortable in Warming and cooler and less comfortable in Cooling (P < 0.01). Participants achieved thermal comfort similarly in all trials (P > 0.09) after 10 ± 7 min and this was maintained until the end of exercise. These results indicate that peripheral temperatures modulate thermal behavior in the cold. PMID:27857959

The Subjective Visual Vertical and the Subjective Haptic Vertical Access Different Gravity Estimates

PubMed Central

Fraser, Lindsey E.; Makooie, Bobbak; Harris, Laurence R.

2015-01-01

The subjective visual vertical (SVV) and the subjective haptic vertical (SHV) both claim to probe the underlying perception of gravity. However, when the body is roll tilted these two measures evoke different patterns of errors with SVV generally becoming biased towards the body (A-effect, named for its discoverer, Hermann Rudolph Aubert) and SHV remaining accurate or becoming biased away from the body (E-effect, short for Entgegengesetzt-effect, meaning “opposite”, i.e., opposite to the A-effect). We compared the two methods in a series of five experiments and provide evidence that the two measures access two different but related estimates of gravitational vertical. Experiment 1 compared SVV and SHV across three levels of whole-body tilt and found that SVV showed an A-effect at larger tilts while SHV was accurate. Experiment 2 found that tilting either the head or the trunk independently produced an A-effect in SVV while SHV remained accurate when the head was tilted on an upright body but showed an A-effect when the body was tilted below an upright head. Experiment 3 repeated these head/body configurations in the presence of vestibular noise induced by using disruptive galvanic vestibular stimulation (dGVS). dGVS abolished both SVV and SHV A-effects while evoking a massive E-effect in the SHV head tilt condition. Experiments 4 and 5 show that SVV and SHV do not combine in an optimally statistical fashion, but when vibration is applied to the dorsal neck muscles, integration becomes optimal. Overall our results suggest that SVV and SHV access distinct underlying gravity percepts based primarily on head and body position information respectively, consistent with a model proposed by Clemens and colleagues. PMID:26716835

Fibromyalgia Pain: Options for Coping

MedlinePlus

... to ourselves inside our heads can affect our perception of pain. Turning negative thoughts into positive ones ... org/diseases-conditions/fibromyalgia/in-depth/fibromyalgia-pain/ART-20047867 . Mayo Clinic Footer Legal Conditions and Terms ...

Augmented Reality Imaging System: 3D Viewing of a Breast Cancer.

PubMed

Douglas, David B; Boone, John M; Petricoin, Emanuel; Liotta, Lance; Wilson, Eugene

2016-01-01

To display images of breast cancer from a dedicated breast CT using Depth 3-Dimensional (D3D) augmented reality. A case of breast cancer imaged using contrast-enhanced breast CT (Computed Tomography) was viewed with the augmented reality imaging, which uses a head display unit (HDU) and joystick control interface. The augmented reality system demonstrated 3D viewing of the breast mass with head position tracking, stereoscopic depth perception, focal point convergence and the use of a 3D cursor and joy-stick enabled fly through with visualization of the spiculations extending from the breast cancer. The augmented reality system provided 3D visualization of the breast cancer with depth perception and visualization of the mass's spiculations. The augmented reality system should be further researched to determine the utility in clinical practice.

Effects of Peripheral Eccentricity and Head Orientation on Gaze Discrimination

PubMed Central

Palanica, Adam; Itier, Roxane J.

2017-01-01

Visual search tasks support a special role for direct gaze in human cognition, while classic gaze judgment tasks suggest the congruency between head orientation and gaze direction plays a central role in gaze perception. Moreover, whether gaze direction can be accurately discriminated in the periphery using covert attention is unknown. In the present study, individual faces in frontal and in deviated head orientations with a direct or an averted gaze were flashed for 150 ms across the visual field; participants focused on a centred fixation while judging the gaze direction. Gaze discrimination speed and accuracy varied with head orientation and eccentricity. The limit of accurate gaze discrimination was less than ±6° eccentricity. Response times suggested a processing facilitation for direct gaze in fovea, irrespective of head orientation, however, by ±3° eccentricity, head orientation started biasing gaze judgments, and this bias increased with eccentricity. Results also suggested a special processing of frontal heads with direct gaze in central vision, rather than a general congruency effect between eye and head cues. Thus, while both head and eye cues contribute to gaze discrimination, their role differs with eccentricity. PMID:28344501

Motion makes sense: an adaptive motor-sensory strategy underlies the perception of object location in rats.

PubMed

Saraf-Sinik, Inbar; Assa, Eldad; Ahissar, Ehud

2015-06-10

Tactile perception is obtained by coordinated motor-sensory processes. We studied the processes underlying the perception of object location in freely moving rats. We trained rats to identify the relative location of two vertical poles placed in front of them and measured at high resolution the motor and sensory variables (19 and 2 variables, respectively) associated with this whiskers-based perceptual process. We found that the rats developed stereotypic head and whisker movements to solve this task, in a manner that can be described by several distinct behavioral phases. During two of these phases, the rats' whiskers coded object position by first temporal and then angular coding schemes. We then introduced wind (in two opposite directions) and remeasured their perceptual performance and motor-sensory variables. Our rats continued to perceive object location in a consistent manner under wind perturbations while maintaining all behavioral phases and relatively constant sensory coding. Constant sensory coding was achieved by keeping one group of motor variables (the "controlled variables") constant, despite the perturbing wind, at the cost of strongly modulating another group of motor variables (the "modulated variables"). The controlled variables included coding-relevant variables, such as head azimuth and whisker velocity. These results indicate that consistent perception of location in the rat is obtained actively, via a selective control of perception-relevant motor variables. Copyright © 2015 the authors 0270-6474/15/358777-13$15.00/0.

Experiments on shape perception in stereoscopic displays

NASA Astrophysics Data System (ADS)

Leroy, Laure; Fuchs, Philippe; Paljic, Alexis; Moreau, Guillaume

2009-02-01

Stereoscopic displays are increasingly used for computer-aided design. The aim is to make virtual prototypes to avoid building real ones, so that time, money and raw materials are saved. But do we really know whether virtual displays render the objects in a realistic way to potential users? In this study, we have performed several experiments in which we compare two virtual shapes to their equivalent in the real world, each of these aiming at a specific issue by a comparison: First, we performed some perception tests to evaluate the importance of head tracking to evaluate if it is better to concentrate our efforts on stereoscopic vision; Second, we have studied the effects of interpupillary distance; Third, we studied the effects of the position of the main object in comparison with the screen. Two different tests are used, the first one using a well-known shape (a sphere) and the second one using an irregular shape but with almost the same colour and dimension. These two tests allow us to determine if symmetry is important in their perception. We show that head tracking has a more important effect on shape perception than stereoscopic vision, especially on depth perception because the subject is able to move around the scene. The study also shows that an object between the subject and the screen is perceived better than an object which is on the screen, even if the latter is better for the eye strain.

Exploding head syndrome.

PubMed

Sharpless, Brian A

2014-12-01

Exploding head syndrome is characterized by the perception of abrupt, loud noises when going to sleep or waking up. They are usually painless, but associated with fear and distress. In spite of the fact that its characteristic symptomatology was first described approximately 150 y ago, exploding head syndrome has received relatively little empirical and clinical attention. Therefore, a comprehensive review of the scientific literature using Medline, PsycINFO, Google Scholar, and PubMed was undertaken. After first discussing the history, prevalence, and associated features, the available polysomnography data and five main etiological theories for exploding head syndrome are summarized. None of these theories has yet reached dominance in the field. Next, the various methods used to assess and treat exploding head syndrome are discussed, as well as the limited outcome data. Finally, recommendations for future measure construction, treatment options, and differential diagnosis are provided. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assessing and improving quality of life in patients with head and neck cancer.

PubMed

Singer, Susanne; Langendijk, Johannes; Yarom, Noam

2013-01-01

Health-related quality of life (QoL) indicates the patients' perception of their health. It depends not only on disease- and treatment-related factors but also on complex inter-relationships of expectations, values and norms, psychologic distress, and comparison with other patients. This article introduces methods and challenges of QoL assessment in patients with head and neck cancer, as well as ways to overcome measurement problems and ways to improve their QoL.

Binocular disparity tuning and visual-vestibular congruency of multisensory neurons in macaque parietal cortex

PubMed Central

Yang, Yun; Liu, Sheng; Chowdhury, Syed A.; DeAngelis, Gregory C.; Angelaki, Dora E.

2012-01-01

Many neurons in the dorsal medial superior temporal (MSTd) and ventral intraparietal (VIP) areas of the macaque brain are multisensory, responding to both optic flow and vestibular cues to self-motion. The heading tuning of visual and vestibular responses can be either congruent or opposite, but only congruent cells have been implicated in cue integration for heading perception. Because of the geometric properties of motion parallax, however, both congruent and opposite cells could be involved in coding self-motion when observers fixate a world-fixed target during translation, if congruent cells prefer near disparities and opposite cells prefer far disparities. We characterized the binocular disparity selectivity and heading tuning of MSTd and VIP cells using random-dot stimuli. Most (70%) MSTd neurons were disparity-selective with monotonic tuning, and there was no consistent relationship between depth preference and congruency of visual and vestibular heading tuning. One-third of disparity-selective MSTd cells reversed their depth preference for opposite directions of motion (direction-dependent disparity tuning, DDD), but most of these cells were unisensory with no tuning for vestibular stimuli. Inconsistent with previous reports, the direction preferences of most DDD neurons do not reverse with disparity. By comparison to MSTd, VIP contains fewer disparity-selective neurons (41%) and very few DDD cells. On average, VIP neurons also preferred higher speeds and nearer disparities than MSTd cells. Our findings are inconsistent with the hypothesis that visual/vestibular congruency is linked to depth preference, and also suggest that DDD cells are not involved in multisensory integration for heading perception. PMID:22159105

Site-specific differences in the association between plantar tactile perception and mobility function in older adults

PubMed Central

Cruz-Almeida, Yenisel; Black, Mieniecia L.; Christou, Evangelos A.; Clark, David J.

2014-01-01

Introduction: Impaired somatosensation is common in older adults and contributes to age-related loss of mobility function. However, little is known about whether somatosensation at different sites on the plantar surface of the foot are differentially related to mobility function. Such a finding may have important implications for clinical care of older adults and other at-risk populations, such as for optimizing interventions (e.g., footwear for augmenting somatosensory feedback) and for improving the efficiency of clinical assessment. Materials and Methods: Tactile perception was evaluated with a 10 g monofilament at four sites on the plantar surface of each foot: great toe (GT), first metatarsal head (MT1), heel (H) and fifth metatarsal head (MT5). Mobility function was assessed with the Berg Balance Scale and walking speed. Results: Sixty-one older adults participated. Tactile perception was significantly positively associated with Berg Balance Score (adjusted r = 0.30 − 0.75; p = 0.03 − < 0.001), with the strongest association found at the site of the MT1. Only at this site was tactile perception found to be significantly associated with usual walking speed (adjusted r = 0.51; p < 0.001) and maximal walking speed (adjusted r = 0.38, p = 0.004). Clinically mild somatosensory impairment at MT1, but not at other sites, was found to yield substantial deficits in both Berg Balance Score and walking speed. Discussion: The present findings indicate that tactile perception at MT1 is more closely linked to mobility function than is tactile perception at GT, MT5 or H. These findings warrant further research to examine whether interventions (e.g., textured insoles) and assessments that preferentially or exclusively focus on the site of MT1 may be more effective for optimizing clinical care. PMID:24782765

Long-lasting effects of neck muscle vibration and contraction on self-motion perception of vestibular origin.

PubMed

Pettorossi, Vito Enrico; Panichi, Roberto; Botti, Fabio Massimo; Biscarini, Andrea; Filippi, Guido Maria; Schieppati, Marco

2015-10-01

To show that neck proprioceptive input can induce long-term effects on vestibular-dependent self-motion perception. Motion perception was assessed by measuring the subject's error in tracking in the dark the remembered position of a fixed target during whole-body yaw asymmetric rotation of a supporting platform, consisting in a fast rightward half-cycle and a slow leftward half-cycle returning the subject to the initial position. Neck muscles were relaxed or voluntarily contracted, and/or vibrated. Whole-body rotation was administered during or at various intervals after the vibration train. The tracking position error (TPE) at the end of the platform rotation was measured during and after the muscle conditioning maneuvers. Neck input produced immediate and sustained changes in the vestibular perceptual response to whole-body rotation. Vibration of the left sterno-cleido-mastoideus (SCM) or right splenius capitis (SC) or isometric neck muscle effort to rotate the head to the right enhanced the TPE by decreasing the perception of the slow rotation. The reverse effect was observed by activating the contralateral muscle. The effects persisted after the end of SCM conditioning, and slowly vanished within several hours, as tested by late asymmetric rotations. The aftereffect increased in amplitude and persistence by extending the duration of the vibration train (from 1 to 10min), augmenting the vibration frequency (from 5 to 100Hz) or contracting the vibrated muscle. Symmetric yaw rotation elicited a negligible TPE, upon which neck muscle vibrations were ineffective. Neck proprioceptive input induces enduring changes in vestibular-dependent self-motion perception, conditional on the vestibular stimulus feature, and on the side and the characteristics of vibration and status of vibrated muscles. This shows that our perception of whole-body yaw-rotation is not only dependent on accurate vestibular information, but is modulated by proprioceptive information related to previously experienced position of head with respect to trunk. Tonic proprioceptive inflow, as might occur as a consequence of enduring or permanent head postures, can induce adaptive plastic changes in vestibular-dependent motion sensitiveness. These changes might be counteracted by vibration of selected neck muscles. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Augmented-reality visualization of brain structures with stereo and kinetic depth cues: system description and initial evaluation with head phantom

NASA Astrophysics Data System (ADS)

Maurer, Calvin R., Jr.; Sauer, Frank; Hu, Bo; Bascle, Benedicte; Geiger, Bernhard; Wenzel, Fabian; Recchi, Filippo; Rohlfing, Torsten; Brown, Christopher R.; Bakos, Robert J.; Maciunas, Robert J.; Bani-Hashemi, Ali R.

2001-05-01

We are developing a video see-through head-mounted display (HMD) augmented reality (AR) system for image-guided neurosurgical planning and navigation. The surgeon wears a HMD that presents him with the augmented stereo view. The HMD is custom fitted with two miniature color video cameras that capture a stereo view of the real-world scene. We are concentrating specifically at this point on cranial neurosurgery, so the images will be of the patient's head. A third video camera, operating in the near infrared, is also attached to the HMD and is used for head tracking. The pose (i.e., position and orientation) of the HMD is used to determine where to overlay anatomic structures segmented from preoperative tomographic images (e.g., CT, MR) on the intraoperative video images. Two SGI 540 Visual Workstation computers process the three video streams and render the augmented stereo views for display on the HMD. The AR system operates in real time at 30 frames/sec with a temporal latency of about three frames (100 ms) and zero relative lag between the virtual objects and the real-world scene. For an initial evaluation of the system, we created AR images using a head phantom with actual internal anatomic structures (segmented from CT and MR scans of a patient) realistically positioned inside the phantom. When using shaded renderings, many users had difficulty appreciating overlaid brain structures as being inside the head. When using wire frames, and texture-mapped dot patterns, most users correctly visualized brain anatomy as being internal and could generally appreciate spatial relationships among various objects. The 3D perception of these structures is based on both stereoscopic depth cues and kinetic depth cues, with the user looking at the head phantom from varying positions. The perception of the augmented visualization is natural and convincing. The brain structures appear rigidly anchored in the head, manifesting little or no apparent swimming or jitter. The initial evaluation of the system is encouraging, and we believe that AR visualization might become an important tool for image-guided neurosurgical planning and navigation.

Effect of eye position during human visual-vestibular integration of heading perception.

PubMed

Crane, Benjamin T

2017-09-01

Visual and inertial stimuli provide heading discrimination cues. Integration of these multisensory stimuli has been demonstrated to depend on their relative reliability. However, the reference frame of visual stimuli is eye centered while inertia is head centered, and it remains unclear how these are reconciled with combined stimuli. Seven human subjects completed a heading discrimination task consisting of a 2-s translation with a peak velocity of 16 cm/s. Eye position was varied between 0° and ±25° left/right. Experiments were done with inertial motion, visual motion, or a combined visual-inertial motion. Visual motion coherence varied between 35% and 100%. Subjects reported whether their perceived heading was left or right of the midline in a forced-choice task. With the inertial stimulus the eye position had an effect such that the point of subjective equality (PSE) shifted 4.6 ± 2.4° in the gaze direction. With the visual stimulus the PSE shift was 10.2 ± 2.2° opposite the gaze direction, consistent with retinotopic coordinates. Thus with eccentric eye positions the perceived inertial and visual headings were offset ~15°. During the visual-inertial conditions the PSE varied consistently with the relative reliability of these stimuli such that at low visual coherence the PSE was similar to that of the inertial stimulus and at high coherence it was closer to the visual stimulus. On average, the inertial stimulus was weighted near Bayesian ideal predictions, but there was significant deviation from ideal in individual subjects. These findings support visual and inertial cue integration occurring in independent coordinate systems. NEW & NOTEWORTHY In multiple cortical areas visual heading is represented in retinotopic coordinates while inertial heading is in body coordinates. It remains unclear whether multisensory integration occurs in a common coordinate system. The experiments address this using a multisensory integration task with eccentric gaze positions making the effect of coordinate systems clear. The results indicate that the coordinate systems remain separate to the perceptual level and that during the multisensory task the perception depends on relative stimulus reliability. Copyright © 2017 the American Physiological Society.

Safety leadership in the teaching laboratories of electrical and electronic engineering departments at Taiwanese Universities.

PubMed

Wu, Tsung-Chih

2008-01-01

Safety has always been one of the principal goals in teaching laboratories. Laboratories cannot serve their educational purpose when accidents occur. The leadership of department heads has a major impact on laboratory safety, so this study discusses the factors affecting safety leadership in teaching laboratories. This study uses a mail survey to explore the perceived safety leadership in electrical and electronic engineering departments at Taiwanese universities. An exploratory factor analysis shows that there are three main components of safety leadership, as measured on a safety leadership scale: safety controlling, safety coaching, and safety caring. The descriptive statistics also reveals that among faculty, the perception of department heads' safety leadership is in general positive. A two-way MANOVA shows that there are interaction effects on safety leadership between university size and instructor age; there are also interaction effects between presence of a safety committee and faculty gender and faculty age. It is therefore necessary to assess organizational factors when determining whether individual factors are the cause of differing perceptions among faculty members. The author also presents advice on improving safety leadership for department heads at small universities and at universities without safety committees.

Head Transplants and Personal Identity: A Philosophical and Literary Survey.

PubMed

Mori, Giuliano

2016-04-01

The criterion of personal identity is clearly called into question by the project to perform a human head transplant. Is identity provided by psychological continuity alone, or does it depend on bodily continuity as well? And how do these different perspectives interface with our notion of mind and mind-body relationship? The reader will be provided with a discussion concerning these problems, together with a philosophical and literary survey about the conception of body-mind relationship from the Greek thought to contemporary philosophy. The analysis will conclude with a discussion concerning the possibility to consider the issue of personal identity from a statistic point of view, which privileges the general perception of identity, so as it has been shaped by the cultural trends of the last four centuries. It could hence be argued that personal identity is not something which can be defined once and for all. On the contrary, the general perception of identity is subject to significant alterations resulting from one's cultural environment. However, the cultural environment itself can be changed by particularly notable events, such as, hypothetically, the successful outcome of a human head transplant. © 2016 John Wiley & Sons Ltd.

Angle-Dependent Distortions in the Perceptual Topology of Acoustic Space

PubMed Central

2018-01-01

By moving sounds around the head and asking listeners to report which ones moved more, it was found that sound sources at the side of a listener must move at least twice as much as ones in front to be judged as moving the same amount. A relative expansion of space in the front and compression at the side has consequences for spatial perception of moving sounds by both static and moving listeners. An accompanying prediction that the apparent location of static sound sources ought to also be distorted agrees with previous work and suggests that this is a general perceptual phenomenon that is not limited to moving signals. A mathematical model that mimics the measured expansion of space can be used to successfully capture several previous findings in spatial auditory perception. The inverse of this function could be used alongside individualized head-related transfer functions and motion tracking to produce hyperstable virtual acoustic environments. PMID:29764312

D3D augmented reality imaging system: proof of concept in mammography.

PubMed

Douglas, David B; Petricoin, Emanuel F; Liotta, Lance; Wilson, Eugene

2016-01-01

The purpose of this article is to present images from simulated breast microcalcifications and assess the pattern of the microcalcifications with a technical development called "depth 3-dimensional (D3D) augmented reality". A computer, head display unit, joystick, D3D augmented reality software, and an in-house script of simulated data of breast microcalcifications in a ductal distribution were used. No patient data was used and no statistical analysis was performed. The D3D augmented reality system demonstrated stereoscopic depth perception by presenting a unique image to each eye, focal point convergence, head position tracking, 3D cursor, and joystick fly-through. The D3D augmented reality imaging system offers image viewing with depth perception and focal point convergence. The D3D augmented reality system should be tested to determine its utility in clinical practice.

Evaluation and comparison of health care Work Environment Scale in military settings.

PubMed

Maloney, J P; Anderson, F D; Gladd, D L; Brown, D L; Hardy, M A

1996-05-01

The purpose of this study was to describe health care providers' perceptions of their work environment at a large U.S. Army medical center, and to compare the findings to other military medical centers. The sample (N = 112) consisted of the professional nursing staff working on the nine inpatient units. The Work Environmental Scale (WES) was used to measure perceptions of the workplace relative to gender, position (head nurses, staff nurses, and agency nurses), specialty nursing (intensive care unit [ICU] versus non-ICU), education (MSN, BSN, and ADN), and patterns of differences between the WES subscales of four military medical centers. Results of the study indicate that there were no significant gender differences. Head nurses, non-ICU nurses, and MSN nurses perceived their environment more positively. There were significant differences in the WES subscales between the military hospitals. Implications for nursing using the WES were recommended.

Perceptions of Emergency Department Physicians Toward Collaborative Practice With Nurse Practitioners in an Emergency Department Setting

DTIC Science & Technology

1998-05-01

questions or they seem to get over their heads they hand it off to the docs. Depending of their training, nurse practitioners in the right situation...conference and explain themselves, it’s just experience, so we just have had a head start there. Years and years of nursing experience isn’t the same...years of medical school is spent in Chemistry and Embryology . I have spent the last 12 years completely dedicated to my career and a physician

An explanatory framework of teachers' perceptions of a positive mealtime environment in a preschool setting.

PubMed

Mita, Satoko C; Gray, Samuel A; Goodell, L Suzanne

2015-07-01

Attending a preschool center may help preschoolers with growth and development that encourage a healthy lifestyle, including sound eating behaviors. Providing a positive mealtime environment (PME) may be one of the keys to fostering a child's healthy eating habits in the classroom. However, a specific definition of a PME, the components of a PME, or directions on how to create one have not been established. The purpose of this study, therefore, was to explore Head Start teachers' perceptions related to a PME and create a conceptual framework representing these perceptions. To achieve this purpose, researchers conducted 65 in-depth phone interviews with Head Start teachers around the US. Applying principles of grounded theory, researchers developed a conceptual framework depicting teachers' perceptions of PME, consisting of five key components: (1) the people (i.e., teachers, kitchen staff, parent volunteers, and children), (2) positive emotional tone (e.g., relaxed and happy), (3) rules, expectations, and routines (e.g., family-style mealtime), (4) operations of a PME (i.e., eating, socialization, and learning), and (5) both short- and long-term outcomes of a PME. With this PME framework, researchers may be able to enhance the effectiveness of nutrition interventions related to a PME, focusing on the factors in the conceptual framework as well as barriers associated with achieving these factors. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of chemotherapy on gene expression of lingual taste receptors in patients with head and neck cancer.

PubMed

Tsutsumi, Rie; Goda, Masakazu; Fujimoto, Chisa; Kanno, Kyoko; Nobe, Misaki; Kitamura, Yoshiaki; Abe, Koji; Kawai, Misako; Matsumoto, Hideki; Sakai, Tohru; Takeda, Noriaki

2016-03-01

We aimed to test the hypothesis that chemotherapy changes the gene expression of taste receptors in the tongue to induce dysgeusia in patients with head and neck cancer. Prospective observation study. We enrolled 21 patients who received chemoradiotherapy and five patients who underwent radiotherapy for head and neck cancer. The messenger RNA (mRNA) levels of the taste receptor subunits T1R1, T1R2, T1R3, and T2R5 were measured in lingual mucosa scrapings obtained with a small spatula. The perception thresholds of umami, sweet, and bitter tastes were assessed by the whole mouth gustatory test. In four patients with severe stomatitis induced by chemoradiotherapy, the mRNA levels of T1R1, T1R2, T1R3, and T2R5 in the lingual mucosa were significantly decreased. However, in 17 patients with mild/moderate stomatitis, the mRNA levels of T1R3 were significantly and transiently decreased, whereas those of T1R1 and T1R2 remained unchanged and those of T2R5 mRNA were significantly and transiently increased after chemotherapy. There was a significant negative correlation between the perception thresholds of umami or sweet tastes and lingual mRNA levels of T1R3 in patients with mild/moderate stomatitis after chemotherapy. Although the perception threshold of bitter taste remained unchanged, lingual mRNA levels of T2R5 were significantly increased in patients who complained of phantogeusia after chemotherapy. Chemotherapy specifically changed the gene expression of T1R3 and T2R5 in head and neck cancer patients with mild/moderate stomatitis, resulting in both dysgeusia of umami and sweet tastes as well as phantogeusia. 4. Laryngoscope, 126:E103-E109, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Searching for the right fit: development of applicant person-organization fit perceptions during the recruitment process.

PubMed

Swider, Brian W; Zimmerman, Ryan D; Barrick, Murray R

2015-05-01

Numerous studies link applicant fit perceptions measured at a single point in time to recruitment outcomes. Expanding upon this prior research by incorporating decision-making theory, this study examines how applicants develop these fit perceptions over the duration of the recruitment process, showing meaningful changes in fit perceptions across and within organizations overtime. To assess the development of applicant fit perceptions, eight assessments of person-organization (PO) fit with up to four different organizations across 169 applicants for 403 job choice decisions were analyzed. Results showed the presence of initial levels and changes in differentiation of applicant PO fit perceptions across organizations, which significantly predicted future job choice. In addition, changes in within-organizational PO fit perceptions across two stages of recruitment predicted applicant job choices among multiple employers. The implications of these results for accurately understanding the development of fit perceptions, relationships between fit perceptions and key recruiting outcomes, and possible limitations of past meta-analytically derived estimates of these relationships are discussed. (c) 2015 APA, all rights reserved.

Displays. [three dimensional analog visual system for aiding pilot space perception

NASA Technical Reports Server (NTRS)

1974-01-01

An experimental investigation made to determine the depth cue of a head movement perspective and image intensity as a function of depth is summarized. The experiment was based on the use of a hybrid computer generated contact analog visual display in which various perceptual depth cues are included on a two dimensional CRT screen. The system's purpose was to impart information, in an integrated and visually compelling fashion, about the vehicle's position and orientation in space. Results show head movement gives a 40% improvement in depth discrimination when the display is between 40 and 100 cm from the subject; intensity variation resulted in as much improvement as head movement.

A qualitative study exploring pupil and school staff perceptions of school meal provision in England.

PubMed

Day, Rhiannon E; Sahota, Pinki; Christian, Meaghan S; Cocks, Kim

2015-11-14

Despite recent attempts to improve the quality of school meals in England through the introduction of school meal standards, uptake remains low. Since the introduction of the universal infant free school meal (UIFSM) scheme in September 2014 all pupils in Reception, Year 1 and Year 2 in English state-funded primary schools are eligible to receive a free lunch. This study aimed to explore the perceptions of pupils, catering managers and head teachers concerning school meal provision in eight primary schools in North England and provides a unique insight into each school's preparation for implementation of UIFSM. A total of thirty-two focus groups were conducted with sixty-four pupils aged 7-8 years (Year 3) and sixty-four pupils aged 9-10 years (Year 5) in June-July 2014, to explore perceptions of school meals. Interviews were carried out with six catering managers and five head teachers concerning catering and the impending implementation of UIFSM. Increasing acceptance of school meals could lead to improved uptake. Pupils desired increased choice and menu variety, including greater variety of vegetables and fruit. Caterers can influence the quantity and types of foods offered to pupils, and there are opportunities for them to promote healthy eating behaviours in the dining room. The important roles of school meal providers, caterers, pupils and parents need to be recognised to improve delivery and acceptability of school meals and ultimately school meal uptake. There were practical challenges to implementation of UIFSM, with some concerns expressed over its feasibility. Head teachers were mainly positive about the potential beneficial impacts of the scheme.

Patient and staff assessment of an audiovisual education tool for head and neck radiation therapy.

PubMed

Morley, Lyndon; McAndrew, Alison; Tse, Karen; Rakaric, Peter; Cummings, Bernard; Cashell, Angela

2013-09-01

The purpose of this study was to understand and compare patient and staff perceptions of a video-based preparatory education tool for head and neck radiotherapy. Patients and staff completed a questionnaire assessing their perceptions of whether the education tool was relevant, clear, complete and reassuring. Staff rated the video's accuracy and anticipated impact on future patient information needs. Demographic information was collected. Open-ended questions were used to elicit additional feedback. Quantitative responses from 50 patients and 48 staff were very positive and not significantly different between the two groups. Content analysis of the qualitative data provided insight into the information and approaches valued by patients and staff and how these differed. Staff members were more critical of the production quality and completeness of information related to procedures and treatment side effects. Patients valued seeing procedures acted out and desired more information about what these experiences would feel like and how to engage in self-care. Although staff-driven development may be an effective method of designing the content and approach of a preparatory education video, care should be taken to consider differences between patient and staff perceptions of information needs.

A head-to-head hands-on comparison of ERCP mechanical simulator (EMS) and Ex-vivo Porcine Stomach Model (PSM)

PubMed Central

Leung, Joseph W; Wang, Dong; Hu, Bing; Lim, Brian

2011-01-01

Background ERCP mechanical simulator (EMS) and ex-vivo porcine stomach model (PSM) have been described. No direct comparison was reported on endoscopists' perception regarding their efficacy for ERCP training Objective Comparative assessment of EMS and PSM. Design Questionnaire survey before and after practice. Setting Hands-on practice workshops. Subjects 22 endoscopists with prior experience in 111±225 (mean±SD) ERCP. Interventions Participants performed scope insertion, selective bile duct cannulation with guide wire and insertion of a single biliary stent. Simulated fluoroscopy with external pin-hole camera (EMS), or with additional transillumination (PSM) was used to monitor exchange of accessories. Main outcome measure Participants rated their understanding and confidence before and after hands-on practice, and credibility of each simulator for ERCP training. Comparative efficacy of EMS and PSM for ERCP education was scored (1=not, 10=very) based on pre and post practice surveys: realism (tissue pliability, papilla anatomy, visual/cannulation realism, wire manipulation, simulated fluoroscopy, overall experience); usefulness (assessment of results, supplementing clinical experience, easy for trainees to learn new skills) and application (overall ease of use, prepare trainees to use real instrument and ease of incorporation into training). Results Before hands-on practice, both EMS and PSM received high scores. After practice, there was a significantly greater increase in confidence score for EMS than PSM (p<0.003). Participants found EMS more useful for training (p=0.017). Limitations: Subjective scores. Conclusions Based on head-to-head hands-on comparison, endoscopists considered both EMS and PSM credible options for improving understanding and supplementing clinical ERCP training. EMS is more useful for basic learning. PMID:22163080

Using EMG to anticipate head motion for virtual-environment applications

NASA Technical Reports Server (NTRS)

Barniv, Yair; Aguilar, Mario; Hasanbelliu, Erion

2005-01-01

In virtual environment (VE) applications, where virtual objects are presented in a see-through head-mounted display, virtual images must be continuously stabilized in space in response to user's head motion. Time delays in head-motion compensation cause virtual objects to "swim" around instead of being stable in space which results in misalignment errors when overlaying virtual and real objects. Visual update delays are a critical technical obstacle for implementing head-mounted displays in applications such as battlefield simulation/training, telerobotics, and telemedicine. Head motion is currently measurable by a head-mounted 6-degrees-of-freedom inertial measurement unit. However, even given this information, overall VE-system latencies cannot be reduced under about 25 ms. We present a novel approach to eliminating latencies, which is premised on the fact that myoelectric signals from a muscle precede its exertion of force, thereby limb or head acceleration. We thus suggest utilizing neck-muscles' myoelectric signals to anticipate head motion. We trained a neural network to map such signals onto equivalent time-advanced inertial outputs. The resulting network can achieve time advances of up to 70 ms.

Using EMG to anticipate head motion for virtual-environment applications.

PubMed

Barniv, Yair; Aguilar, Mario; Hasanbelliu, Erion

2005-06-01

In virtual environment (VE) applications, where virtual objects are presented in a see-through head-mounted display, virtual images must be continuously stabilized in space in response to user's head motion. Time delays in head-motion compensation cause virtual objects to "swim" around instead of being stable in space which results in misalignment errors when overlaying virtual and real objects. Visual update delays are a critical technical obstacle for implementing head-mounted displays in applications such as battlefield simulation/training, telerobotics, and telemedicine. Head motion is currently measurable by a head-mounted 6-degrees-of-freedom inertial measurement unit. However, even given this information, overall VE-system latencies cannot be reduced under about 25 ms. We present a novel approach to eliminating latencies, which is premised on the fact that myoelectric signals from a muscle precede its exertion of force, thereby limb or head acceleration. We thus suggest utilizing neck-muscles' myoelectric signals to anticipate head motion. We trained a neural network to map such signals onto equivalent time-advanced inertial outputs. The resulting network can achieve time advances of up to 70 ms.

Head multidetector computed tomography: emergency medicine physicians overestimate the pretest probability and legal risk of significant findings.

PubMed

Baskerville, Jerry Ray; Herrick, John

2012-02-01

This study focuses on clinically assigned prospective estimated pretest probability and pretest perception of legal risk as independent variables in the ordering of multidetector computed tomographic (MDCT) head scans. Our primary aim is to measure the association between pretest probability of a significant finding and pretest perception of legal risk. Secondarily, we measure the percentage of MDCT scans that physicians would not order if there was no legal risk. This study is a prospective, cross-sectional, descriptive analysis of patients 18 years and older for whom emergency medicine physicians ordered a head MDCT. We collected a sample of 138 patients subjected to head MDCT scans. The prevalence of a significant finding in our population was 6%, yet the pretest probability expectation of a significant finding was 33%. The legal risk presumed was even more dramatic at 54%. These data support the hypothesis that physicians presume the legal risk to be significantly higher than the risk of a significant finding. A total of 21% or 15% patients (95% confidence interval, ±5.9%) would not have been subjected to MDCT if there was no legal risk. Physicians overestimated the probability that the computed tomographic scan would yield a significant result and indicated an even greater perceived medicolegal risk if the scan was not obtained. Physician test-ordering behavior is complex, and our study queries pertinent aspects of MDCT testing. The magnification of legal risk vs the pretest probability of a significant finding is demonstrated. Physicians significantly overestimated pretest probability of a significant finding on head MDCT scans and presumed legal risk. Copyright © 2012 Elsevier Inc. All rights reserved.

Modification of Eye Movements and Motion Perception during Off-Vertical Axis Rotation

NASA Technical Reports Server (NTRS)

Wood, S. J.; Reschke, M. F.; Denise, P.; CLement, G.

2006-01-01

Constant velocity Off-Vertical Axis Rotation (OVAR) imposes a continuously varying orientation of the head and body relative to gravity. The ensuing ocular reflexes include modulation of both torsional and horizontal eye movements as a function of the varying linear acceleration along the lateral plane, and modulation of vertical and vergence eye movements as a function of the varying linear acceleration along the sagittal plane. Previous studies have demonstrated that tilt and translation otolith-ocular responses, as well as motion perception, vary as a function of stimulus frequency during OVAR. The purpose of this study is to examine normative OVAR responses in healthy human subjects, and examine adaptive changes in astronauts following short duration space flight at low (0.125 Hz) and high (0.5 Hz) frequencies. Data was obtained on 24 normative subjects (14 M, 10 F) and 14 (13 M, 1F) astronaut subjects. To date, astronauts have participated in 3 preflight sessions (n=14) and on R+0/1 (n=7), R+2 (n= 13) and R+4 (n= 13) days after landing. Subjects were rotated in darkness about their longitudinal axis 20 deg off-vertical at constant rates of 45 and 180 deg/s, corresponding to 0.125 and 0.5 Hz. Binocular responses were obtained with video-oculography. Perceived motion was evaluated using verbal reports and a two-axis joystick (pitch and roll tilt) mounted on top of a two-axis linear stage (anterior-posterior and medial-lateral translation). Eye responses were obtained in ten of the normative subjects with the head and trunk aligned, and then with the head turned relative to the trunk 40 deg to the right or left of center. Sinusoidal curve fits were used to derive amplitude, phase and bias of the responses over several cycles at each stimulus frequency. Eye responses during 0.125 Hz OVAR were dominated by modulation of torsional and vertical eye position, compensatory for tilt relative to gravity. While there is a bias horizontal slow phase velocity (SPV), the modulation of horizontal and vergence SPV is negligible at this lower stimulus frequency. Eye responses during 0.5 Hz OVAR; however, are characterized by modulation of horizontal and vergence SPV, compensatory for translation in the lateral and sagittal planes, respectively. Neither amplitude nor bias velocities were significantly altered by head-on-trunk position. The phases of the ocular reflexes, on the other hand, shifted towards alignment with the head. During the lower frequency OVAR, subjects reported the perception of progressing along the edge of a cone. During higher frequency OVAR, subjects reported the perception of progressing along the edge of an upright cylinder. In contrast to the eye movements, the phase of both perceived tilt and translation motion is not altered by stimulus frequency. Preliminary results from astronaut data suggest that the ocular responses are not substantially altered by short-duration spaceflight. However, compared to preflight averages, astronauts reported greater amplitude of both perceived tilt and translation at low and high frequency, respectively, during early post-flight testing. We conclude that the neural processing to distinguish tilt and translation linear acceleration stimuli differs between eye movements and motion perception. The results from modifying head-on-trunk position are consistent with the modulation of ocular reflexes during OVAR being primarily mediated by the otoliths in response to the sinusoidally varying linear acceleration along the interaural and naso-occipital head axis. While the tilt and translation ocular reflexes appear to operate in an independent fashion, the timing of perceived tilt and translation influence each other. We conclude that the perceived motion path during linear acceleration in darkness results from a composite representation of tilt and translation inputs from both vestibular and somatosensory systems.

Acrylic Resin Molding Based Head Fixation Technique in Rodents.

PubMed

Roh, Mootaek; Lee, Kyungmin; Jang, Il-Sung; Suk, Kyoungho; Lee, Maan-Gee

2016-01-12

Head fixation is a technique of immobilizing animal's head by attaching a head-post on the skull for rigid clamping. Traditional head fixation requires surgical attachment of metallic frames on the skull. The attached frames are then clamped to a stationary platform resulting in immobilization of the head. However, metallic frames for head fixation have been technically difficult to design and implement in general laboratory environment. In this study, we provide a novel head fixation method. Using a custom-made head fixation bar, head mounter is constructed during implantation surgery. After the application of acrylic resin for affixing implants such as electrodes and cannula on the skull, additional resins applied on top of that to build a mold matching to the port of the fixation bar. The molded head mounter serves as a guide rails, investigators conveniently fixate the animal's head by inserting the head mounter into the port of the fixation bar. This method could be easily applicable if implantation surgery using dental acrylics is necessary and might be useful for laboratories that cannot easily fabricate CNC machined metal head-posts.

75 FR 61479 - Kendall Head Tidal Energy Project; Notice of Preliminary Permit Application Accepted for Filing...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-05

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13801-000] Kendall Head Tidal Energy Project; Notice of Preliminary Permit Application Accepted for Filing and Soliciting... Federal Power Act, proposing to study the feasibility of the Kendall Head Tidal Energy Project, located in...

Fostering interprofessional collaboration through a family-centred programme for grandparent-headed families.

PubMed

Lee, Youjung; Quranta, Judith; Anderson, Elizabeth

2017-07-01

Interprofessional education (IPE) is now widely considered an essential part of preparing professionals to work more effectively with marginalised families, such as grandparent-headed families. This study aims to explore the potential for IPE through a family-centred programme for grandparent-headed families during professional preparation for education, social work, and nursing students to foster collaboration. Using mixed methods with concurrent data collection and analyses, this study suggests that participation in IPE can positively impact perceptions of interprofessional collaboration to better meet the multifaceted needs of grandparent-headed families by increasing awareness and self-efficacy for interprofessional collaboration in schools and deepening understandings of non-traditional families. Implications highlight possibilities for more flexible and integrated professional identities in working with children and their families as well as the potential for future school professionals to embrace more comprehensive services in schools.

Gender differences in farmers' responses to climate change adaptation in Yongqiao District, China.

PubMed

Jin, Jianjun; Wang, Xiaomin; Gao, Yiwei

2015-12-15

This study examines the gender differences in farmers' responses to climate change adaption in Yongqiao District, China. A random sampling technique was used to select 220 household heads, while descriptive statistics and binary logit models were used to analyze the data obtained from the households. We determine that male and female respondents are not significantly different in their knowledge and perceptions of climate change, but there is a gender difference in adopting climate change adaptation measures. Male-headed households are more likely to adopt new technology for water conservation and to increase investment in irrigation infrastructure. The research also indicates that the adaptation decisions of male and female heads are influenced by different sets of factors. The findings of this research help to elucidate the determinants of climate change adaptation decisions for male and female-headed households and the strategic interventions necessary for effective adaptation. Copyright © 2015 Elsevier B.V. All rights reserved.

Gender differences in head-neck segment dynamic stabilization during head acceleration.

PubMed

Tierney, Ryan T; Sitler, Michael R; Swanik, C Buz; Swanik, Kathleen A; Higgins, Michael; Torg, Joseph

2005-02-01

Recent epidemiological research has revealed that gender differences exist in concussion incidence but no study has investigated why females may be at greater risk of concussion. Our purpose was to determine whether gender differences existed in head-neck segment kinematic and neuromuscular control variables responses to an external force application with and without neck muscle preactivation. Forty (20 females and 20 males) physically active volunteers participated in the study. The independent variables were gender, force application (known vs unknown), and force direction (forced flexion vs forced extension). The dependent variables were kinematic and EMG variables, head-neck segment stiffness, and head-neck segment flexor and extensor isometric strength. Statistical analyses consisted of multiple multivariate and univariate analyses of variance, follow-up univariate analyses of variance, and t-tests (P < or = 0.05). Gender differences existed in head-neck segment dynamic stabilization during head angular acceleration. Females exhibited significantly greater head-neck segment peak angular acceleration (50%) and displacement (39%) than males despite initiating muscle activity significantly earlier (SCM only) and using a greater percentage of their maximum head-neck segment muscle activity (79% peak activity and 117% muscle activity area). The head-neck segment angular acceleration differences may be because females exhibited significantly less isometric strength (49%), neck girth (30%), and head mass (43%), resulting in lower levels of head-neck segment stiffness (29%). For our subject demographic, the results revealed gender differences in head-neck segment dynamic stabilization during head acceleration in response to an external force application. Females exhibited significantly greater head-neck segment peak angular acceleration and displacement than males despite initiating muscle activity earlier (SCM only) and using a greater percentage of their maximum head-neck segment muscle activity.

Perception and biodynamics in unalerted precrash response.

PubMed

McGehee, Daniel V; Carsten, Oliver M J

2010-01-01

This research seeks to better understand unalerted driver response just prior to a serious vehicle crash. Few studies have been able to view a crash from the inside-with a camera focused on the driver and occupants. Four studies are examined: 1) a high-fidelity simulator study with an unalerted intersection incursion crash among 107 drivers; 2) four crashes from the Virginia Tech Transportation Institute (VTTI) 100 car study; 3) 58 crashes from vehicles equipped with an event triggered video recorder; and 4) a custom-designed high-fidelity simulator experiment that examined unalerted driver response to a head-on crash with a heavy truck. Analyses concentrate on decomposing driver perception, action, facial and postural changes with a focus on describing the neurophysiologic mechanisms designed to respond to danger. Results indicate that drivers involved in severe crashes generally have preview that an impact is about to occur. They respond first with vehicle control inputs (accelerator pedal release) along with facial state changes and withdrawal of the head back towards the head restraint. These responses frequently occur almost simultaneously, providing safety system designers with a number of reliable driver performance measures to monitor. Understanding such mechanisms may assist future advanced driver assistance systems (ADAS), advanced restraints, model development of advanced anthropomorphic test dummies (ATDs), injury prediction and the integration of active and passive safety systems.

Modeling depth from motion parallax with the motion/pursuit ratio

PubMed Central

Nawrot, Mark; Ratzlaff, Michael; Leonard, Zachary; Stroyan, Keith

2014-01-01

The perception of unambiguous scaled depth from motion parallax relies on both retinal image motion and an extra-retinal pursuit eye movement signal. The motion/pursuit ratio represents a dynamic geometric model linking these two proximal cues to the ratio of depth to viewing distance. An important step in understanding the visual mechanisms serving the perception of depth from motion parallax is to determine the relationship between these stimulus parameters and empirically determined perceived depth magnitude. Observers compared perceived depth magnitude of dynamic motion parallax stimuli to static binocular disparity comparison stimuli at three different viewing distances, in both head-moving and head-stationary conditions. A stereo-viewing system provided ocular separation for stereo stimuli and monocular viewing of parallax stimuli. For each motion parallax stimulus, a point of subjective equality (PSE) was estimated for the amount of binocular disparity that generates the equivalent magnitude of perceived depth from motion parallax. Similar to previous results, perceived depth from motion parallax had significant foreshortening. Head-moving conditions produced even greater foreshortening due to the differences in the compensatory eye movement signal. An empirical version of the motion/pursuit law, termed the empirical motion/pursuit ratio, which models perceived depth magnitude from these stimulus parameters, is proposed. PMID:25339926

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

PubMed

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.

Perception of combined translation and rotation in the horizontal plane in humans

PubMed Central

2016-01-01

Thresholds and biases of human motion perception were determined for yaw rotation and sway (left-right) and surge (fore-aft) translation, independently and in combination. Stimuli were 1 Hz sinusoid in acceleration with a peak velocity of 14°/s or cm/s. Test stimuli were adjusted based on prior responses, whereas the distracting stimulus was constant. Seventeen human subjects between the ages of 20 and 83 completed the experiments and were divided into 2 groups: younger and older than 50. Both sway and surge translation thresholds significantly increased when combined with yaw rotation. Rotation thresholds were not significantly increased by the presence of translation. The presence of a yaw distractor significantly biased perception of sway translation, such that during 14°/s leftward rotation, the point of subjective equality (PSE) occurred with sway of 3.2 ± 0.7 (mean ± SE) cm/s to the right. Likewise, during 14°/s rightward motion, the PSE was with sway of 2.9 ± 0.7 cm/s to the left. A sway distractor did not bias rotation perception. When subjects were asked to report the direction of translation while varying the axis of yaw rotation, the PSE at which translation was equally likely to be perceived in either direction was 29 ± 11 cm anterior to the midline. These results demonstrated that rotation biased translation perception, such that it is minimized when rotating about an axis anterior to the head. Since the combination of translation and rotation during ambulation is consistent with an axis anterior to the head, this may reflect a mechanism by which movements outside the pattern that occurs during ambulation are perceived. PMID:27334952

Postural complexity influences development in infants born preterm with brain injury: relating perception-action theory to 3 cases.

PubMed

Dusing, Stacey C; Izzo, Theresa; Thacker, Leroy R; Galloway, James Cole

2014-10-01

Perception-action theory suggests a cyclical relationship between movement and perceptual information. In this case series, changes in postural complexity were used to quantify an infant's action and perception during the development of early motor behaviors. Three infants born preterm with periventricular white matter injury were included. Longitudinal changes in postural complexity (approximate entropy of the center of pressure), head control, reaching, and global development, measured with the Test of Infant Motor Performance and the Bayley Scales of Infant and Toddler Development, were assessed every 0.5 to 3 months during the first year of life. All 3 infants demonstrated altered postural complexity and developmental delays. However, the timing of the altered postural complexity and the type of delays varied among the infants. For infant 1, reduced postural complexity or limited action while learning to control her head in the midline position may have contributed to her motor delay. However, her ability to adapt her postural complexity eventually may have supported her ability to learn from her environment, as reflected in her relative cognitive strength. For infant 2, limited early postural complexity may have negatively affected his learning through action, resulting in cognitive delay. For infant 3, an increase in postural complexity above typical levels was associated with declining neurological status. Postural complexity is proposed as a measure of perception and action in the postural control system during the development of early behaviors. An optimal, intermediate level of postural complexity supports the use of a variety of postural control strategies and enhances the perception-action cycle. Either excessive or reduced postural complexity may contribute to developmental delays in infants born preterm with white matter injury. © 2014 American Physical Therapy Association.

Subjective visual horizontal during follow-up after unilateral vestibular deafferentation with gentamicin.

PubMed

Tribukait, A; Bergenius, J; Brantberg, K

1998-07-01

The subjective visual horizontal (SVH) was measured by means of a small, rotatable, luminous line in darkness in the upright head and body position and at 10, 20 and 30 degrees of tilt to the right and left before, and repeatedly during a follow-up period of 1 year after intratympanic gentamicin instillations in 12 patients with recurrent vertigo attacks. This treatment caused a loss of the bithermal caloric responses on the diseased side. Shortly after treatment there was a significant tilt of SVH towards the treated side (group mean = 10.6 degrees). Repeated testing made it possible to characterize mathematically the changes with time for SVH. For the group of patients as a whole this otolithic component of vestibular compensation was best described by a power function, SVH = 8.65t(-0.16) degrees, where t is time in days after maximum tilt of SVH. After 1 year, SVH was still significantly tilted towards the treated side (group mean = 3.16 degrees). Gentamicin treatment also caused a significant reduction in the perception of head and body tilt towards the deafferented side, while the perception of tilt towards the healthy side did not show any significant changes. During follow-up there was a gradual improvement in the perception of tilt towards the treated side. However, a significant asymmetry in roll-tilt perception was still present 1 year after deafferentation. There was no correlation between SVH in the upright position and roll-tilt perception, suggesting that these parameters are to some extent dependent on different afferent input from the vestibular organ. They were also found to be complementary for the detection of vestibular disturbance.

Optimal faces for gender and expression: a new technique for measuring dynamic templates used in face perception.

PubMed

Poirier, Frédéric J A M; Faubert, Jocelyn

2012-06-22

Facial expressions are important for human communications. Face perception studies often measure the impact of major degradation (e.g., noise, inversion, short presentations, masking, alterations) on natural expression recognition performance. Here, we introduce a novel face perception technique using rich and undegraded stimuli. Participants modified faces to create optimal representations of given expressions. Using sliders, participants adjusted 53 face components (including 37 dynamic) including head, eye, eyebrows, mouth, and nose shape and position. Data was collected from six participants and 10 conditions (six emotions + pain + gender + neutral). Some expressions had unique features (e.g., frown for anger, upward-curved mouth for happiness), whereas others had shared features (e.g., open eyes and mouth for surprise and fear). Happiness was different from other emotions. Surprise was different from other emotions except fear. Weighted sum morphing provides acceptable stimuli for gender-neutral and dynamic stimuli. Many features were correlated, including (1) head size with internal feature sizes as related to gender, (2) internal feature scaling, and (3) eyebrow height and eye openness as related to surprise and fear. These findings demonstrate the method's validity for measuring the optimal facial expressions, which we argue is a more direct measure of their internal representations.

Electrical Stimulation of the Ear, Head, Cranial Nerve, or Cortex for the Treatment of Tinnitus: A Scoping Review

PubMed Central

Adjamian, Peyman

2016-01-01

Tinnitus is defined as the perception of sound in the absence of an external source. It is often associated with hearing loss and is thought to result from abnormal neural activity at some point or points in the auditory pathway, which is incorrectly interpreted by the brain as an actual sound. Neurostimulation therapies therefore, which interfere on some level with that abnormal activity, are a logical approach to treatment. For tinnitus, where the pathological neuronal activity might be associated with auditory and other areas of the brain, interventions using electromagnetic, electrical, or acoustic stimuli separately, or paired electrical and acoustic stimuli, have been proposed as treatments. Neurostimulation therapies should modulate neural activity to deliver a permanent reduction in tinnitus percept by driving the neuroplastic changes necessary to interrupt abnormal levels of oscillatory cortical activity and restore typical levels of activity. This change in activity should alter or interrupt the tinnitus percept (reduction or extinction) making it less bothersome. Here we review developments in therapies involving electrical stimulation of the ear, head, cranial nerve, or cortex in the treatment of tinnitus which demonstrably, or are hypothesised to, interrupt pathological neuronal activity in the cortex associated with tinnitus. PMID:27403346

Peripheral optogenetic stimulation induces whisker movement and sensory perception in head-fixed mice.

PubMed

Park, Sunmee; Bandi, Akhil; Lee, Christian R; Margolis, David J

2016-06-08

We discovered that optical stimulation of the mystacial pad in Emx1-Cre;Ai27D transgenic mice induces whisker movements due to activation of ChR2 expressed in muscles controlling retraction and protraction. Using high-speed videography in anesthetized mice, we characterize the amplitude of whisker protractions evoked by varying the intensity, duration, and frequency of optogenetic stimulation. Recordings from primary somatosensory cortex (S1) in anesthetized mice indicated that optogenetic whisker pad stimulation evokes robust yet longer latency responses than mechanical whisker stimulation. In head-fixed mice trained to report optogenetic whisker pad stimulation, psychometric curves showed similar dependence on stimulus duration as evoked whisker movements and S1 activity. Furthermore, optogenetic stimulation of S1 in expert mice was sufficient to substitute for peripheral stimulation. We conclude that whisker protractions evoked by optogenetic activation of whisker pad muscles results in cortical activity and sensory perception, consistent with the coding of evoked whisker movements by reafferent sensory input.

Headed reinforcement in concrete structure: State of the art

NASA Astrophysics Data System (ADS)

Alrasyid, Harun; Yoganata, Yehezkiel Septian; Suluch, Munarus; Iranata, Data

2017-11-01

At the reinforced concrete structure, the utilization of the headed bar has provided simpler installation, less congestion of reinforcement and more effective anchorage compared to conventional reinforcing bars anchorage by hooks and bends. A literature review related to the use of headed reinforcement are exhibited. The paper discusses the behavior anchorage of headed reinforcement, and the application of at beam column joint and as shear reinforcement. The review of headed bar includes historical background, the available commercial product and the summary of the experimental results that uses this application. Based on current study the suggestion for further research are provided.

On the Vertigo Due to Static Magnetic Fields

PubMed Central

Mian, Omar S.; Li, Yan; Antunes, Andre; Glover, Paul M.; Day, Brian L.

2013-01-01

Vertigo is sometimes experienced in and around MRI scanners. Mechanisms involving stimulation of the vestibular system by movement in magnetic fields or magnetic field spatial gradients have been proposed. However, it was recently shown that vestibular-dependent ocular nystagmus is evoked when stationary in homogenous static magnetic fields. The proposed mechanism involves Lorentz forces acting on endolymph to deflect semicircular canal (SCC) cupulae. To investigate whether vertigo arises from a similar mechanism we recorded qualitative and quantitative aspects of vertigo and 2D eye movements from supine healthy adults (n = 25) deprived of vision while pushed into the 7T static field of an MRI scanner. Exposures were variable and included up to 135s stationary at 7T. Nystagmus was mainly horizontal, persisted during long-exposures with partial decline, and reversed upon withdrawal. The dominant vertiginous perception with the head facing up was rotation in the horizontal plane (85% incidence) with a consistent direction across participants. With the head turned 90 degrees in yaw the perception did not transform into equivalent vertical plane rotation, indicating a context-dependency of the perception. During long exposures, illusory rotation lasted on average 50 s, including 42 s whilst stationary at 7T. Upon withdrawal, perception re-emerged and reversed, lasting on average 30 s. Onset fields for nystagmus and perception were significantly correlated (p<.05). Although perception did not persist as long as nystagmus, this is a known feature of continuous SSC stimulation. These observations, and others in the paper, are compatible with magnetic-field evoked-vertigo and nystagmus sharing a common mechanism. With this interpretation, response decay and reversal upon withdrawal from the field, are due to adaptation to continuous vestibular input. Although the study does not entirely exclude the possibility of mechanisms involving transient vestibular stimulation during movement in and out of the bore, we argue these are less likely. PMID:24205304

On the vertigo due to static magnetic fields.

PubMed

Mian, Omar S; Li, Yan; Antunes, Andre; Glover, Paul M; Day, Brian L

2013-01-01

Vertigo is sometimes experienced in and around MRI scanners. Mechanisms involving stimulation of the vestibular system by movement in magnetic fields or magnetic field spatial gradients have been proposed. However, it was recently shown that vestibular-dependent ocular nystagmus is evoked when stationary in homogenous static magnetic fields. The proposed mechanism involves Lorentz forces acting on endolymph to deflect semicircular canal (SCC) cupulae. To investigate whether vertigo arises from a similar mechanism we recorded qualitative and quantitative aspects of vertigo and 2D eye movements from supine healthy adults (n = 25) deprived of vision while pushed into the 7T static field of an MRI scanner. Exposures were variable and included up to 135s stationary at 7T. Nystagmus was mainly horizontal, persisted during long-exposures with partial decline, and reversed upon withdrawal. The dominant vertiginous perception with the head facing up was rotation in the horizontal plane (85% incidence) with a consistent direction across participants. With the head turned 90 degrees in yaw the perception did not transform into equivalent vertical plane rotation, indicating a context-dependency of the perception. During long exposures, illusory rotation lasted on average 50 s, including 42 s whilst stationary at 7T. Upon withdrawal, perception re-emerged and reversed, lasting on average 30 s. Onset fields for nystagmus and perception were significantly correlated (p<.05). Although perception did not persist as long as nystagmus, this is a known feature of continuous SSC stimulation. These observations, and others in the paper, are compatible with magnetic-field evoked-vertigo and nystagmus sharing a common mechanism. With this interpretation, response decay and reversal upon withdrawal from the field, are due to adaptation to continuous vestibular input. Although the study does not entirely exclude the possibility of mechanisms involving transient vestibular stimulation during movement in and out of the bore, we argue these are less likely.

The perceived perceptions of head school nurses in developing school nursing roles within schools.

PubMed

Morberg, Siv; Lagerström, Monica; Dellve, Lotta

2009-11-01

To gain a deeper understanding of how Swedish head school nurses perceive their leadership in developing school health care. A well-functioning school health care is important for promoting the health of children and young people. Constructivist-grounded theory was used to analyse 11 individual interviews with nine head school nurses. Head school nurses strive to find a balance between what they experience as vague formal goals and strong informal goals which leads to creating local goals in order to develop school health care. The head school nurse's job is experienced as a divided and pioneering job in which there is uncertainty about the leadership role. They provide individual support to school nurses, are the link between school nurses and decision makers and highlight the importance of school nurses' work to organizational leaders. This study shows that school health care needs to be founded on evidence-based methods. Therefore, a structured plan for education and training in school health care management, based on research and in cooperation with the academic world, would develop the head school nurses' profession, strengthen the position of school health care and advance the school nurses' work.

The phonetic rhythm/syntax headedness connection: Evidence from Tagalog

NASA Astrophysics Data System (ADS)

Bird, Sonya; Fais, Laurel; Werker, Janet

2005-04-01

Ramus, Nespor, and Mehler [Cognition (1999)] show that the rhythm of a language (broadly: stress- versus syllable- versus mora-timing) results from the proportion of vocalic material in an utterance (%V) and the standard deviation of consonantal intervals (delta-C). Based on 14 languages, Shukla, Nespor, and Mehler [submitted] further argue that rhythm is correlated with syntactic headedness: low %V is correlated with head-first languages (e.g., English); high %V is correlated with head-final languages (e.g., Japanese). Together, these proposals have important implications for language acquisition: infants can discriminate across rhythm classes [Nazzi, Bertoncini, and Mehler, J. Exp. Psych: Human Perception and Performance (1998)]. If rhythm, as defined by %V and delta-C, can predict headedness, then infants can potentially use rhythm information to bootstrap into their languages syntactic structure. This paper reports on a study analyzing rhythm in a language not yet considered: Tagalog. Results support the Shukla et al. proposal in an interesting way: based on its %V and delta-C, Tagalog falls between head-first and head-last languages, slighty closer to the head-first group. This placement correlates well with the fact that, although Tagalog is said to be primarily head-first syntactically, head-last phrases are permitted and common in the language.

Anatomical limits on interaural time differences: an ecological perspective

PubMed Central

Hartmann, William M.; Macaulay, Eric J.

2013-01-01

Human listeners, and other animals too, use interaural time differences (ITD) to localize sounds. If the sounds are pure tones, a simple frequency factor relates the ITD to the interaural phase difference (IPD), for which there are known iso-IPD boundaries, 90°, 180°… defining regions of spatial perception. In this article, iso-IPD boundaries for humans are translated into azimuths using a spherical head model (SHM), and the calculations are checked by free-field measurements. The translated boundaries provide quantitative tests of an ecological interpretation for the dramatic onset of ITD insensitivity at high frequencies. According to this interpretation, the insensitivity serves as a defense against misinformation and can be attributed to limits on binaural processing in the brainstem. Calculations show that the ecological explanation passes the tests only if the binaural brainstem properties evolved or developed consistent with heads that are 50% smaller than current adult heads. Measurements on more realistic head shapes relax that requirement only slightly. The problem posed by the discrepancy between the current head size and a smaller, ideal head size was apparently solved by the evolution or development of central processes that discount large IPDs in favor of interaural level differences. The latter become more important with increasing head size. PMID:24592209

Exploding head syndrome is common in college students.

PubMed

Sharpless, Brian A

2015-08-01

Exploding head syndrome is characterized by the perception of loud noises during sleep-wake or wake-sleep transitions. Although episodes by themselves are relatively harmless, it is a frightening phenomenon that may result in clinical consequences. At present there are little systematic data on exploding head syndrome, and prevalence rates are unknown. It has been hypothesized to be rare and to occur primarily in older (i.e. 50+ years) individuals, females, and those suffering from isolated sleep paralysis. In order to test these hypotheses, 211 undergraduate students were assessed for both exploding head syndrome and isolated sleep paralysis using semi-structured diagnostic interviews: 18.00% of the sample experienced lifetime exploding head syndrome, this reduced to 16.60% for recurrent cases. Though not more common in females, it was found in 36.89% of those diagnosed with isolated sleep paralysis. Exploding head syndrome episodes were accompanied by clinically significant levels of fear, and a minority (2.80%) experienced it to such a degree that it was associated with clinically significant distress and/or impairment. Contrary to some earlier theorizing, exploding head syndrome was found to be a relatively common experience in younger individuals. Given the potential clinical impacts, it is recommended that it be assessed more regularly in research and clinical settings. © 2015 European Sleep Research Society.

Administrators' and Faculty Members' Perceptions of the Performance Appraisal Interview.

ERIC Educational Resources Information Center

McDowell, Earl E.

An exploratory study examined how administrators (department heads/chairs) perceive faculty members, as well as themselves, in the performance appraisal interview. Subjects, 450 faculty members and 200 administrators at a midwestern university, answered an Appraisal Interview Questionnaire in which they rated administrator performance, content and…

Objective measurement of head movement differences in children with and without autism spectrum disorder.

PubMed

Martin, Katherine B; Hammal, Zakia; Ren, Gang; Cohn, Jeffrey F; Cassell, Justine; Ogihara, Mitsunori; Britton, Jennifer C; Gutierrez, Anibal; Messinger, Daniel S

2018-01-01

Deficits in motor movement in children with autism spectrum disorder (ASD) have typically been characterized qualitatively by human observers. Although clinicians have noted the importance of atypical head positioning (e.g. social peering and repetitive head banging) when diagnosing children with ASD, a quantitative understanding of head movement in ASD is lacking. Here, we conduct a quantitative comparison of head movement dynamics in children with and without ASD using automated, person-independent computer-vision based head tracking (Zface). Because children with ASD often exhibit preferential attention to nonsocial versus social stimuli, we investigated whether children with and without ASD differed in their head movement dynamics depending on stimulus sociality. The current study examined differences in head movement dynamics in children with ( n  = 21) and without ASD ( n  = 21). Children were video-recorded while watching a 16-min video of social and nonsocial stimuli. Three dimensions of rigid head movement-pitch (head nods), yaw (head turns), and roll (lateral head inclinations)-were tracked using Zface. The root mean square of pitch, yaw, and roll was calculated to index the magnitude of head angular displacement (quantity of head movement) and angular velocity (speed). Compared with children without ASD, children with ASD exhibited greater yaw displacement, indicating greater head turning, and greater velocity of yaw and roll, indicating faster head turning and inclination. Follow-up analyses indicated that differences in head movement dynamics were specific to the social rather than the nonsocial stimulus condition. Head movement dynamics (displacement and velocity) were greater in children with ASD than in children without ASD, providing a quantitative foundation for previous clinical reports. Head movement differences were evident in lateral (yaw and roll) but not vertical (pitch) movement and were specific to a social rather than nonsocial condition. When presented with social stimuli, children with ASD had higher levels of head movement and moved their heads more quickly than children without ASD. Children with ASD may use head movement to modulate their perception of social scenes.

Science Education in Nigeria: An Examination of People's Perceptions about Female Participation in Science, Mathematics and Technology

NASA Astrophysics Data System (ADS)

Ogunjuyigbe, Peter O.; Ojofeitimi, Ebenezer O.; Akinlo, Ambrose

2006-10-01

The paper brings to focus people's perception about female involvement in science, mathematics and technology (SMT). Data for the study were obtained from a survey conducted in March, 2005 in two Local Government Areas of Osun state, Southwest Nigeria. The paper reveals that: (i) about 57% of household heads, 45.6% of mothers and 57.6% of the children are of the opinion that both boys and girls are given equal right to SMT education (ii) social forces play an important role in determining people's attitude to SMT (iii) though, parents and stakeholders perceptions about girls' participation in some professions is changing, however, socio-cultural and economic factors still determine which sex to encourage to read SMT.

Emergency Physician Attitudes, Preferences, and Risk Tolerance for Stroke as a Potential Cause of Dizziness Symptoms.

PubMed

Kene, Mamata V; Ballard, Dustin W; Vinson, David R; Rauchwerger, Adina S; Iskin, Hilary R; Kim, Anthony S

2015-09-01

We evaluated emergency physicians' (EP) current perceptions, practice, and attitudes towards evaluating stroke as a cause of dizziness among emergency department patients. We administered a survey to all EPs in a large integrated healthcare delivery system. The survey included clinical vignettes, perceived utility of historical and exam elements, attitudes about the value of and requisite post-test probability of a clinical prediction rule for dizziness. We calculated descriptive statistics and post-test probabilities for such a clinical prediction rule. The response rate was 68% (366/535). Respondents' median practice tenure was eight years (37% female, 92% emergency medicine board certified). Symptom quality and typical vascular risk factors increased suspicion for stroke as a cause of dizziness. Most respondents reported obtaining head computed tomography (CT) (74%). Nearly all respondents used and felt confident using cranial nerve and limb strength testing. A substantial minority of EPs used the Epley maneuver (49%) and HINTS (head-thrust test, gaze-evoked nystagmus, and skew deviation) testing (30%); however, few EPs reported confidence in these tests' bedside application (35% and 16%, respectively). Respondents favorably viewed applying a properly validated clinical prediction rule for assessment of immediate and 30-day stroke risk, but indicated it would have to reduce stroke risk to <0.5% to be clinically useful. EPs report relying on symptom quality, vascular risk factors, simple physical exam elements, and head CT to diagnose stroke as the cause of dizziness, but would find a validated clinical prediction rule for dizziness helpful. A clinical prediction rule would have to achieve a 0.5% post-test stroke probability for acceptability.

Applicant Personality and Procedural Justice Perceptions of Group Selection Interviews.

PubMed

Bye, Hege H; Sandal, Gro M

2016-01-01

We investigated how job applicants' personalities influence perceptions of the structural and social procedural justice of group selection interviews (i.e., a group of several applicants being evaluated simultaneously). We especially addressed trait interactions between neuroticism and extraversion (the affective plane) and extraversion and agreeableness (the interpersonal plane). Data on personality (pre-interview) and justice perceptions (post-interview) were collected in a field study among job applicants ( N  = 97) attending group selection interviews for positions as teachers in a Norwegian high school. Interaction effects in hierarchical regression analyses showed that perceptions of social and structural justice increased with levels of extraversion among high scorers on neuroticism. Among emotionally stable applicants, however, being introverted or extraverted did not matter to justice perceptions. Extraversion did not impact on the perception of social justice for applicants low in agreeableness. Agreeable applicants, however, experienced the group interview as more socially fair when they were also extraverted. The impact of applicant personality on justice perceptions may be underestimated if traits interactions are not considered. Procedural fairness ratings for the group selection interview were high, contrary to the negative reactions predicted by other researchers. There was no indication that applicants with desirable traits (i.e., traits predictive of job performance) reacted negatively to this selection tool. Despite the widespread use of interviews in selection, previous studies of applicant personality and fairness reactions have not included interviews. The study demonstrates the importance of previously ignored trait interactions in understanding applicant reactions.

Visual Behaviors and Adaptations Associated with Cortical and Ocular Impairment in Children.

ERIC Educational Resources Information Center

Jan, J. E.; Groenveld, M.

1993-01-01

This article shows the usefulness of understanding visual behaviors in the diagnosis of various types of visual impairments that are due to ocular and cortical disorders. Behaviors discussed include nystagmus, ocular motor dyspraxia, head position, close viewing, field loss adaptations, mannerisms, photophobia, and abnormal color perception. (JDD)

Perceptions of the School Self-Evaluation Process: The Case of Abu Dhabi

ERIC Educational Resources Information Center

Blaik Hourani, Rida; Litz, David

2016-01-01

The Abu Dhabi Education Council (ADEC) has initiated educational change and school improvements. As part of the school reform agenda, ADEC has introduced school self-evaluation-Irtiqaa (SSE-Irtiqaa). This research probes the effectiveness of school administrators (SAs), including principals, vice principals, academic principals, and heads of…

Leader Behavior of Head Nurses through the Perceptions of Self and Others.

DTIC Science & Technology

1984-01-01

studies ......... 17 III. Methodology .. ....... ...... ......................... 25 Population and sample ........ .*... ............ . 25 Procedures...60....*.* Implications for future rsearch ............. 62 Implications for nursing comaunity...*................. 63 *.......****.*** 75 Vi List...able to distinguish the personality traits of leaders from the personality traits of non -leaders. The traits of leaders, she contends, are communication

Predictors of Authoritative Parenting in Kindergarten.

ERIC Educational Resources Information Center

Colbert, Karen K.; Hegland, Susan M.

This study examined the relationships among parent psychological well-being, parents' perceptions of their children's social competence, and reported use of authoritative parenting strategies during the kindergarten year. Parents of 179 kindergarten children in a small Midwestern U.S. city who were also involved in a Head Start Transition Study…

Perceptions of Culturally Diverse Head Start Families: A Focus Group Study

ERIC Educational Resources Information Center

Riley, Jeanetta G.; Gichuru, Margaret; Robertson, Jo

2012-01-01

Teachers who embrace culturally relevant practices support children's learning by infusing "cultural referents" into the curriculum to provide children with learning opportunities that are related to their experiences outside of the classroom. They strive to establish congruency between home, community, and school and to use knowledge of…

Technology and the Unseen World of Gifted Students: Social Emotional Needs

ERIC Educational Resources Information Center

Cross, Tracy L.

2004-01-01

The social and emotional development of gifted students can be influenced by many factors. Genetics, experiences, learning, family values, perceptions, and interactions all contribute to the development of gifted children. Under the heading of experiences is students? use of computers. The potential effects of using these technologies is…

Cross-Modal Facilitation in Speech Prosody

ERIC Educational Resources Information Center

Foxton, Jessica M.; Riviere, Louis-David; Barone, Pascal

2010-01-01

Speech prosody has traditionally been considered solely in terms of its auditory features, yet correlated visual features exist, such as head and eyebrow movements. This study investigated the extent to which visual prosodic features are able to affect the perception of the auditory features. Participants were presented with videos of a speaker…

Constructing Identities: Female Head Teachers' Perceptions and Experiences in the Primary Sector

ERIC Educational Resources Information Center

Jones, Deborah

2017-01-01

This article presents research undertaken with female headteachers in UK primary schools and explores several influential discourses in relation to female headteachers' identities. It considers themes inherent in women's narratives as they reflect upon their professional lives and discusses various identities inhabited by female leaders which…

Perceptions of Head Start Teachers about Culturally Relevant Practice

ERIC Educational Resources Information Center

Gichuru, Margaret; Riley, Jeanetta G.; Robertson, Jo; Park, Mi-Hwa

2015-01-01

Children bring a variety of cultural, linguistic, and social backgrounds into the preschool classroom. When teachers consider these backgrounds, they are better able to create environments that reflect children's cultures and to design learning experiences that build on children's prior experiences. This qualitative study examined how children's…

Literature for Children: Avoiding Controversy and Intellectual Challenge.

ERIC Educational Resources Information Center

Adams, Dennis M.

1986-01-01

Discusses lack of literature on controversial subjects that can help prepare children and young adults to deal perceptively with complexities of modern world. Highlights include meeting the issues head-on, glorifying armed conflict in video media, avoiding issues of nuclear war, and intellectual depth and dealing with controversial issues. (12…

Personal and Interpersonal Aspects of Effective Team-Oriented Headship in the Primary School.

ERIC Educational Resources Information Center

Johnston, John; Pickersgill, Susan

1992-01-01

Examines elementary principals' perceptions of themselves as stretched to the limit, undervalued, undersupported, and underresourced. Heads tend to interpret the majority of organizational problems as a reflection of their personal failure. A team-oriented approach to headship would ameliorate this situation by creating more efficient work…

Latency Requirements for Head-Worn Display S/EVS Applications

NASA Technical Reports Server (NTRS)

Bailey, Randall E.; Trey Arthur, J. J., III; Williams, Steven P.

2004-01-01

NASA s Aviation Safety Program, Synthetic Vision Systems Project is conducting research in advanced flight deck concepts, such as Synthetic/Enhanced Vision Systems (S/EVS), for commercial and business aircraft. An emerging thrust in this activity is the development of spatially-integrated, large field-of-regard information display systems. Head-worn or helmet-mounted display systems are being proposed as one method in which to meet this objective. System delays or latencies inherent to spatially-integrated, head-worn displays critically influence the display utility, usability, and acceptability. Research results from three different, yet similar technical areas flight control, flight simulation, and virtual reality are collectively assembled in this paper to create a global perspective of delay or latency effects in head-worn or helmet-mounted display systems. Consistent definitions and measurement techniques are proposed herein for universal application and latency requirements for Head-Worn Display S/EVS applications are drafted. Future research areas are defined.

Latency requirements for head-worn display S/EVS applications

NASA Astrophysics Data System (ADS)

Bailey, Randall E.; Arthur, Jarvis J., III; Williams, Steven P.

2004-08-01

NASA's Aviation Safety Program, Synthetic Vision Systems Project is conducting research in advanced flight deck concepts, such as Synthetic/Enhanced Vision Systems (S/EVS), for commercial and business aircraft. An emerging thrust in this activity is the development of spatially-integrated, large field-of-regard information display systems. Head-worn or helmet-mounted display systems are being proposed as one method in which to meet this objective. System delays or latencies inherent to spatially-integrated, head-worn displays critically influence the display utility, usability, and acceptability. Research results from three different, yet similar technical areas - flight control, flight simulation, and virtual reality - are collectively assembled in this paper to create a global perspective of delay or latency effects in head-worn or helmet-mounted display systems. Consistent definitions and measurement techniques are proposed herein for universal application and latency requirements for Head-Worn Display S/EVS applications are drafted. Future research areas are defined.

Augmented reality in neurosurgery: a systematic review.

PubMed

Meola, Antonio; Cutolo, Fabrizio; Carbone, Marina; Cagnazzo, Federico; Ferrari, Mauro; Ferrari, Vincenzo

2017-10-01

Neuronavigation has become an essential neurosurgical tool in pursuing minimal invasiveness and maximal safety, even though it has several technical limitations. Augmented reality (AR) neuronavigation is a significant advance, providing a real-time updated 3D virtual model of anatomical details, overlaid on the real surgical field. Currently, only a few AR systems have been tested in a clinical setting. The aim is to review such devices. We performed a PubMed search of reports restricted to human studies of in vivo applications of AR in any neurosurgical procedure using the search terms "Augmented reality" and "Neurosurgery." Eligibility assessment was performed independently by two reviewers in an unblinded standardized manner. The systems were qualitatively evaluated on the basis of the following: neurosurgical subspecialty of application, pathology of treated lesions and lesion locations, real data source, virtual data source, tracking modality, registration technique, visualization processing, display type, and perception location. Eighteen studies were included during the period 1996 to September 30, 2015. The AR systems were grouped by the real data source: microscope (8), hand- or head-held cameras (4), direct patient view (2), endoscope (1), and X-ray fluoroscopy (1) head-mounted display (1). A total of 195 lesions were treated: 75 (38.46 %) were neoplastic, 77 (39.48 %) neurovascular, and 1 (0.51 %) hydrocephalus, and 42 (21.53 %) were undetermined. Current literature confirms that AR is a reliable and versatile tool when performing minimally invasive approaches in a wide range of neurosurgical diseases, although prospective randomized studies are not yet available and technical improvements are needed.

Combustor with non-circular head end

DOEpatents

Kim, Won -Wook; McMahan, Kevin Weston

2015-09-29

The present application provides a combustor for use with a gas turbine engine. The combustor may include a head end with a non-circular configuration, a number of fuel nozzles positioned about the head end, and a transition piece extending downstream of the head end.

77 FR 13610 - Proposed Information Collection Activity; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-07

... Information Collection Activity; Comment Request Proposed Project Title: Head Start Facilities Construction, Purchase and Major Renovations. OMB No.: 0970-0193. Description: The Head Start Bureau is proposing to.... The part contains the administrative requirements applicable to Head Start and Early Head Start...

Perception and Biodynamics in Unalerted Precrash Response

PubMed Central

McGehee, Daniel V.; Carsten, Oliver M.J.

2010-01-01

This research seeks to better understand unalerted driver response just prior to a serious vehicle crash. Few studies have been able to view a crash from the inside—with a camera focused on the driver and occupants. Four studies are examined: 1) a high-fidelity simulator study with an unalerted intersection incursion crash among 107 drivers; 2) four crashes from the Virginia Tech Transportation Institute (VTTI) 100 car study; 3) 58 crashes from vehicles equipped with an event triggered video recorder; and 4) a custom-designed high-fidelity simulator experiment that examined unalerted driver response to a head-on crash with a heavy truck. Analyses concentrate on decomposing driver perception, action, facial and postural changes with a focus on describing the neurophysiologic mechanisms designed to respond to danger. Results indicate that drivers involved in severe crashes generally have preview that an impact is about to occur. They respond first with vehicle control inputs (accelerator pedal release) along with facial state changes and withdrawal of the head back towards the head restraint. These responses frequently occur almost simultaneously, providing safety system designers with a number of reliable driver performance measures to monitor. Understanding such mechanisms may assist future advanced driver assistance systems (ADAS), advanced restraints, model development of advanced anthropomorphic test dummies (ATDs), injury prediction and the integration of active and passive safety systems. PMID:21050614

Living in a Patient-Centric Universe.

PubMed

Kraus, Dennis H

2016-12-01

Patients with head and neck cancer face a number of challenges in terms of treatment, cure of their underlying malignant condition, and quality of survivorship. This presentation will focus on the patient perception of both the quality of care and the empathy and availability of the head and neck oncology team. It has become evident that the quality of survivorship plays a central role in the patient's decision-making process. The process of decision making by the patient facing head and neck cancer and the impact on treatment choices will be explored. The ability of the patient and her or his support system to navigate through the increasingly complicated health care system will be considered, with an emphasis on strategies for success. Finally, the role of the of the head and neck surgeon, and the need for physician wellness in predicating successful patient outcomes will be considered. The ultimate goal of achieving optimal care, superior patient outcomes, and patient satisfaction is the true objective of the concept of living in a patient-centric universe.

A neural model of motion processing and visual navigation by cortical area MST.

PubMed

Grossberg, S; Mingolla, E; Pack, C

1999-12-01

Cells in the dorsal medial superior temporal cortex (MSTd) process optic flow generated by self-motion during visually guided navigation. A neural model shows how interactions between well-known neural mechanisms (log polar cortical magnification, Gaussian motion-sensitive receptive fields, spatial pooling of motion-sensitive signals and subtractive extraretinal eye movement signals) lead to emergent properties that quantitatively simulate neurophysiological data about MSTd cell properties and psychophysical data about human navigation. Model cells match MSTd neuron responses to optic flow stimuli placed in different parts of the visual field, including position invariance, tuning curves, preferred spiral directions, direction reversals, average response curves and preferred locations for stimulus motion centers. The model shows how the preferred motion direction of the most active MSTd cells can explain human judgments of self-motion direction (heading), without using complex heading templates. The model explains when extraretinal eye movement signals are needed for accurate heading perception, and when retinal input is sufficient, and how heading judgments depend on scene layouts and rotation rates.

Head Up Displays. (Latest Citations from the Aerospace Database)

NASA Technical Reports Server (NTRS)

1997-01-01

The bibliography contains citations concerning the design, fabrication, and applications of head up displays (HUDs). Applications include military aircraft, helicopters, space shuttle, and commercial aircraft. Functions of the display include instrument approach, target tracking, and navigation. The head up display provides for an integrated avionics system with the pilot in the loop. (Contains 50-250 citations and includes a subject term index and title list.)

Head Up Displays. (Latest citations from the Aerospace Database)

NASA Technical Reports Server (NTRS)

1996-01-01

The bibliography contains citations concerning the design, fabrication, and applications of head up displays (HUDs). Applications include military aircraft, helicopters, space shuttle, and commercial aircraft. Functions of the display include instrument approach, target tracking, and navigation. The head up display provides for an integrated avionics system with the pilot in the loop. (Contains 50-250 citations and includes a subject term index and title list.)

Development of a high resolution voxelised head phantom for medical physics applications.

PubMed

Giacometti, V; Guatelli, S; Bazalova-Carter, M; Rosenfeld, A B; Schulte, R W

2017-01-01

Computational anthropomorphic phantoms have become an important investigation tool for medical imaging and dosimetry for radiotherapy and radiation protection. The development of computational phantoms with realistic anatomical features contribute significantly to the development of novel methods in medical physics. For many applications, it is desirable that such computational phantoms have a real-world physical counterpart in order to verify the obtained results. In this work, we report the development of a voxelised phantom, the HIGH_RES_HEAD, modelling a paediatric head based on the commercial phantom 715-HN (CIRS). HIGH_RES_HEAD is unique for its anatomical details and high spatial resolution (0.18×0.18mm 2 pixel size). The development of such a phantom was required to investigate the performance of a new proton computed tomography (pCT) system, in terms of detector technology and image reconstruction algorithms. The HIGH_RES_HEAD was used in an ad-hoc Geant4 simulation modelling the pCT system. The simulation application was previously validated with respect to experimental results. When compared to a standard spatial resolution voxelised phantom of the same paediatric head, it was shown that in pCT reconstruction studies, the use of the HIGH_RES_HEAD translates into a reduction from 2% to 0.7% of the average relative stopping power difference between experimental and simulated results thus improving the overall quality of the head phantom simulation. The HIGH_RES_HEAD can also be used for other medical physics applications such as treatment planning studies. A second version of the voxelised phantom was created that contains a prototypic base of skull tumour and surrounding organs at risk. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Hawk Eyes II: Diurnal Raptors Differ in Head Movement Strategies When Scanning from Perches

PubMed Central

O'Rourke, Colleen T.; Pitlik, Todd; Hoover, Melissa; Fernández-Juricic, Esteban

2010-01-01

Background Relatively little is known about the degree of inter-specific variability in visual scanning strategies in species with laterally placed eyes (e.g., birds). This is relevant because many species detect prey while perching; therefore, head movement behavior may be an indicator of prey detection rate, a central parameter in foraging models. We studied head movement strategies in three diurnal raptors belonging to the Accipitridae and Falconidae families. Methodology/Principal Findings We used behavioral recording of individuals under field and captive conditions to calculate the rate of two types of head movements and the interval between consecutive head movements. Cooper's Hawks had the highest rate of regular head movements, which can facilitate tracking prey items in the visually cluttered environment they inhabit (e.g., forested habitats). On the other hand, Red-tailed Hawks showed long intervals between consecutive head movements, which is consistent with prey searching in less visually obstructed environments (e.g., open habitats) and with detecting prey movement from a distance with their central foveae. Finally, American Kestrels have the highest rates of translational head movements (vertical or frontal displacements of the head keeping the bill in the same direction), which have been associated with depth perception through motion parallax. Higher translational head movement rates may be a strategy to compensate for the reduced degree of eye movement of this species. Conclusions Cooper's Hawks, Red-tailed Hawks, and American Kestrels use both regular and translational head movements, but to different extents. We conclude that these diurnal raptors have species-specific strategies to gather visual information while perching. These strategies may optimize prey search and detection with different visual systems in habitat types with different degrees of visual obstruction. PMID:20877650

Hawk eyes II: diurnal raptors differ in head movement strategies when scanning from perches.

PubMed

O'Rourke, Colleen T; Pitlik, Todd; Hoover, Melissa; Fernández-Juricic, Esteban

2010-09-22

Relatively little is known about the degree of inter-specific variability in visual scanning strategies in species with laterally placed eyes (e.g., birds). This is relevant because many species detect prey while perching; therefore, head movement behavior may be an indicator of prey detection rate, a central parameter in foraging models. We studied head movement strategies in three diurnal raptors belonging to the Accipitridae and Falconidae families. We used behavioral recording of individuals under field and captive conditions to calculate the rate of two types of head movements and the interval between consecutive head movements. Cooper's Hawks had the highest rate of regular head movements, which can facilitate tracking prey items in the visually cluttered environment they inhabit (e.g., forested habitats). On the other hand, Red-tailed Hawks showed long intervals between consecutive head movements, which is consistent with prey searching in less visually obstructed environments (e.g., open habitats) and with detecting prey movement from a distance with their central foveae. Finally, American Kestrels have the highest rates of translational head movements (vertical or frontal displacements of the head keeping the bill in the same direction), which have been associated with depth perception through motion parallax. Higher translational head movement rates may be a strategy to compensate for the reduced degree of eye movement of this species. Cooper's Hawks, Red-tailed Hawks, and American Kestrels use both regular and translational head movements, but to different extents. We conclude that these diurnal raptors have species-specific strategies to gather visual information while perching. These strategies may optimize prey search and detection with different visual systems in habitat types with different degrees of visual obstruction.

Integration of visual and non-visual self-motion cues during voluntary head movements in the human brain.

PubMed

Schindler, Andreas; Bartels, Andreas

2018-05-15

Our phenomenological experience of the stable world is maintained by continuous integration of visual self-motion with extra-retinal signals. However, due to conventional constraints of fMRI acquisition in humans, neural responses to visuo-vestibular integration have only been studied using artificial stimuli, in the absence of voluntary head-motion. We here circumvented these limitations and let participants to move their heads during scanning. The slow dynamics of the BOLD signal allowed us to acquire neural signal related to head motion after the observer's head was stabilized by inflatable aircushions. Visual stimuli were presented on head-fixed display goggles and updated in real time as a function of head-motion that was tracked using an external camera. Two conditions simulated forward translation of the participant. During physical head rotation, the congruent condition simulated a stable world, whereas the incongruent condition added arbitrary lateral motion. Importantly, both conditions were precisely matched in visual properties and head-rotation. By comparing congruent with incongruent conditions we found evidence consistent with the multi-modal integration of visual cues with head motion into a coherent "stable world" percept in the parietal operculum and in an anterior part of parieto-insular cortex (aPIC). In the visual motion network, human regions MST, a dorsal part of VIP, the cingulate sulcus visual area (CSv) and a region in precuneus (Pc) showed differential responses to the same contrast. The results demonstrate for the first time neural multimodal interactions between precisely matched congruent versus incongruent visual and non-visual cues during physical head-movement in the human brain. The methodological approach opens the path to a new class of fMRI studies with unprecedented temporal and spatial control over visuo-vestibular stimulation. Copyright © 2018 Elsevier Inc. All rights reserved.

Age, Health and Attractiveness Perception of Virtual (Rendered) Human Hair

PubMed Central

Fink, Bernhard; Hufschmidt, Carla; Hirn, Thomas; Will, Susanne; McKelvey, Graham; Lankhof, John

2016-01-01

The social significance of physical appearance and beauty has been documented in many studies. It is known that even subtle manipulations of facial morphology and skin condition can alter people’s perception of a person’s age, health and attractiveness. While the variation in facial morphology and skin condition cues has been studied quite extensively, comparably little is known on the effect of hair on social perception. This has been partly caused by the technical difficulty of creating appropriate stimuli for investigations of people’s response to systematic variation of certain hair characteristics, such as color and style, while keeping other features constant. Here, we present a modeling approach to the investigation of human hair perception using computer-generated, virtual (rendered) human hair. In three experiments, we manipulated hair diameter (Experiment 1), hair density (Experiment 2), and hair style (Experiment 3) of human (female) head hair and studied perceptions of age, health and attractiveness. Our results show that even subtle changes in these features have an impact on hair perception. We discuss our findings with reference to previous studies on condition-dependent quality cues in women that influence human social perception, thereby suggesting that hair is a salient feature of human physical appearance, which contributes to the perception of beauty. PMID:28066276

Posturography of ataxia induced by Coriolis- and Purkinje-effects.

PubMed

Fitger, C; Brandt, T

1982-02-01

Vestibular Coriolis- and Purkinje-effect, which are known to induce vertigo, were investigated with respect to body posture. One aim of this investigation was to provide information concerning clinical vertigo symptoms. Standing on a rotatable stabilometer, 25 healthy subjects had to execute lateral head tilts during (Coriolis), or after (Purkinje), rotation varied with different constant velocities. The conditions were varied with respect to eyes open vs. eyes closed, head upright vs. head tilt to the right and left, direction of rotation clockwise vs. counterclockwise, active vs. passive head tilt, and active vs. passive body rotation. The results supported the expectation that destabilization was less severe with open than with closed eyes and that sway amplitudes were increased after head tilt as well as with a higher velocity of rotation. The direction of the induced body shift was, as expected, opposite to the initial vestibular stimulus. A forward shift after stop without head tilt was frequently found, being independent of the previous direction of rotation. Reported perceptions coincided mostly not with the initial vestibular signal but rather with the actual movement of compensation. Active instead of passive movements did not produce clearly different effects. The Purkinje experiment appeared to be equivalent to the situation when a patient with an acute lesion of a horizontal vestibular canal bends his head. The stabilogram under this condition may allow a prediction of the side of the lesion.

Does the hair influence heat extraction from the head during head cooling under heat stress?

PubMed Central

SHIN, Sora; PARK, Joonhee; LEE, Joo-Young

2015-01-01

The purpose of this study was to investigate the effects of head hair on thermoregulatory responses when cooling the head under heat stress. Eight young males participated in six experimental conditions: normal hair (100–130 mm length) and cropped hair (5 mm length) with three water inlet temperatures of 10, 15, and 20°C. The head and neck of subjects were cooled by a liquid perfused hood while immersing legs at 42°C water for 60 min in a sitting position at the air temperature of 28°C with 30% RH. The results showed that heat removal from the normal hair condition was not significantly different from the cropped hair condition. Rectal and mean skin temperatures, and sweat rate showed no significant differences between the normal and cropped hair conditions. Heat extraction from the head was significantly greater in 10°C than in 15 or 20°C cooling (p<0.05) for both normal and cropped hair, whereas subjects preferred the 15°C more than the 10 or 20°C cooling regimen. These results indicate that the selection of effective cooling temperature is more crucial than the length of workers’ hair during head cooling under heat stress, and such selection should be under the consideration of subjective perceptions with physiological responses. PMID:26165361

77 FR 31857 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-30

... OMB Review; Comment Request Title: 1309 Head Start Facilities Construction, Purchase and Major Renovations. OMB No.: 0970-0193. Description: The Head Start Bureau is proposing to renew, without changes... administrative requirements applicable to Head Start and Early Head Start grantees, when applying for funding to...

14 CFR § 1230.123 - Early termination of research support: Evaluation of applications and proposals.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 5 2014-01-01 2014-01-01 false Early termination of research support... termination of research support: Evaluation of applications and proposals. (a) The department or agency head... prescribed in applicable program requirements, when the department or agency head finds an institution has...

Lower extremity work is associated with club head velocity during the golf swing in experienced golfers.

PubMed

McNally, M P; Yontz, N; Chaudhari, A M

2014-08-01

While the golf swing is a complex whole body movement requiring coordination of all joints to achieve maximum ball velocity, the kinetic contribution of the lower extremities to club head velocity has not been quantified, despite the perception that the legs are a primary source of power during the swing. Mechanical power at the hips, knees, and ankles was estimated during the downswing phase of a full swing with a driver using a passive optical motion capture system and 2 force plates for adult males across a range of age and self-reported skill levels. Total work by the lower extremities was calculated by integrating the powers of all 6 joints over the downswing. Regression analyses showed that total lower extremity work was a strong predictor of club head velocity (R=0.63). Secondary analyses showed different relationships to club head velocity in lead and trail leg lower extremity joints, but none of these were as predictive of club head velocity as the total work performed by the lower extremities. These results provide quantitative evidence that the lower body's kinetic contribution may be an important factor in achieving greater club head velocity, contributing to greater driving distance and overall golf performance. © Georg Thieme Verlag KG Stuttgart · New York.

49 CFR 173.314 - Compressed gases in tank cars and multi-unit tank cars.

Code of Federal Regulations, 2013 CFR

2013-10-01

... applicable authorized tank car specification and must be equipped with a head shield as prescribed in § 179... jacket and head shield. When the jacket and head shield are made from any authorized steel with a minimum... jacket and head shield must be increased by a factor of 1.157. Forming allowances for heads are not...

49 CFR 173.314 - Compressed gases in tank cars and multi-unit tank cars.

Code of Federal Regulations, 2014 CFR

2014-10-01

... applicable authorized tank car specification and must be equipped with a head shield as prescribed in § 179... jacket and head shield. When the jacket and head shield are made from any authorized steel with a minimum... jacket and head shield must be increased by a factor of 1.157. Forming allowances for heads are not...

Changes in head and neck position have a greater effect on elbow joint position sense in people with whiplash-associated disorders.

PubMed

Knox, Joanna Joy; Beilstein, Darren Jay; Charles, Scott Darren; Aarseth, Geir Arne; Rayar, Shivanthi; Treleaven, Julia; Hodges, Paul William

2006-01-01

It has been shown that perception of elbow joint position is affected by changes in head and neck position. Further, people with whiplash-associated disorders (WAD) present with deficits in upper limb coordination and movement. This study is aimed to determine whether the effect of changes in head position on elbow joint position error (JPE) is more pronounced in people with WAD, and to determine whether this is related to the participant's pain and anxiety levels. Nine people with chronic and disabling WAD and 11 healthy people participated in this experiment. The ability to reproduce a position at the elbow joint was assessed after changes in the position of the head and neck to 30 degrees , and with the head in the midline. Pain was monitored in WAD participants. Absolute elbow JPE with the head in neutral was not different between WAD and control participants (P=0.5). Changes in the head and neck position increased absolute elbow JPE in the WAD group (P<0.05), but did not affect elbow JPE in the control group (P=0.4). There was a connection between pain during testing and the effect of changes in head position on elbow JPE (P<0.05). Elbow JPE is affected by movement of the head and neck, with smaller angles of neck rotation in people with WAD than in healthy individuals. This observation may explain deficits in upper limb coordination in people with WAD, which may be due to the presence of pain or reduced range of motion in this population.

Head lice: the feelings people have.

PubMed

Parison, Julie C; Speare, Richard; Canyon, Deon V

2013-02-01

Head lice are a source of amusement for outsiders and an embarrassing nuisance to those who have to deal with them. Our study collected the emotions experienced by people dealing with head lice. An area with extremely sparse literature, our purpose is to inform the development of more effective programs to control head lice. We asked "what were your feelings upon discovery of head lice?" as part of a study exploring the experience of those treating head lice. A short questionnaire was available via the authors' head lice information internet site. A total of 294 eligible responses were collected over several months and analyzed, supported by QSR N6. The predominantly female (90 · 9%) respondents were residents of Australia (56 · 1%), USA (20 · 4%), Canada (7 · 2%), or UK (4 · 4%), and working full-time (43·0%) or part-time (34 · 2%). Reactions and feelings fell into three categories: strong (n = 320; 79% of all stated emotions), mediocre (n = 56; 20%), and neutral (n = 29; 9 · 8%). There were no positive emotions. The significant negative reaction was expected. The range of feeling expressed demonstrates the stigma held for these ectoparasites within western market economies. This contrasts with conceptions of head lice in traditional societies. The negative social effects of this perception create more problematic issues than the infection itself; these include quarantine, overtreatment, and a potentially negative psychological impact. Head lice control strategies and programs that address these negative emotional reactions may prove more effective than current biomedical focus. © 2013 The International Society of Dermatology.

49 CFR 572.82 - Head.

Code of Federal Regulations, 2010 CFR

2010-10-01

... OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES 9-Month Old Child § 572.82 Head. The head consists of the assembly shown in drawing LP 1049/A and conforms to each of the applicable drawings listed...

Failure to Obtain Computed Tomography Imaging in Head Trauma: A Review of Relevant Case Law.

PubMed

Lindor, Rachel A; Boie, Eric T; Campbell, Ronna L; Hess, Erik P; Sadosty, Annie T

2015-12-01

The objectives were to describe lawsuits against providers for failing to order head computed tomography (CT) in cases of head trauma and to determine the potential effects of available clinical decision rules (CDRs) on each lawsuit. The authors collected jury verdicts, settlements, and court opinions regarding alleged malpractice for failure to order head CT in the setting of head trauma from 1972 through February 2014 from an online legal research tool (WestlawNext). Data were abstracted onto a standardized data form. The performance of five CDRs was evaluated. Sixty relevant cases were identified (52 adult, eight children). Of 48 cases with known outcomes, providers were found negligent in 10 cases (six adult, four pediatric), settled in 11 cases (nine adult, two pediatric), and were found not liable in 27 cases. In all 10 cases in which providers were found negligent, every applicable CDR studied would have indicated the need for head CT. In all eight cases involving children, the applicable CDR would have suggested the need for head CT or observation. A review of legal cases reported in a major online legal research system revealed 60 lawsuits in which providers were sued for failing to order head CTs in cases of head trauma. In all cases in which providers were found negligent, CT imaging or observation would have been indicated by every applicable CDR. © 2015 by the Society for Academic Emergency Medicine.

Student Perceptions regarding Vocational High School Teachers' Problem Solving Methods against Undesired Behaviors in Classroom Management

ERIC Educational Resources Information Center

Gulcan, Murat Gurkan

2010-01-01

Teachers' classroom management approach varies depending on several factors such as the social, psychological, cultural and educational status of the student, classroom level, the physical conditions of the school, organization structure. There are different approaches in classroom management. These approaches are gathered under three headings in…

Development of Multisensory Spatial Integration and Perception in Humans

ERIC Educational Resources Information Center

Neil, Patricia A.; Chee-Ruiter, Christine; Scheier, Christian; Lewkowicz, David J.; Shimojo, Shinsuke

2006-01-01

Previous studies have shown that adults respond faster and more reliably to bimodal compared to unimodal localization cues. The current study investigated for the first time the development of audiovisual (A-V) integration in spatial localization behavior in infants between 1 and 10 months of age. We observed infants' head and eye movements in…

Head Start Teachers' Perceptions of Implementing Classroom Positive Behavior Support: Insights for Teacher Training

ERIC Educational Resources Information Center

Novetsky, Jason S.

2009-01-01

Younger children are demonstrating increasingly more serious problem behaviors (Walker, 1998). The present study concerned further investigation of early implementation of a promising behavior management model known as Positive Behavior Support (PBS). PBS has been shown to be successful in elementary and secondary schools (Metzler, Biglan, &…

Dissonant Role Perception and Paradoxical Adjustments: An Exploratory Study on Medical Residents' Collaboration with Senior Doctors and Head Nurses

ERIC Educational Resources Information Center

Fiordelli, Maddalena; Schulz, Peter J.; Caiata Zufferey, Maria

2014-01-01

A good collaboration between health professionals is considered to have benefits for patients, healthcare staff, and organizations. Nevertheless, effective interprofessional collaboration is difficult to achieve. This is particularly true for collaboration between Medical Residents (MRs) and the immediate colleagues they interact with, as Senior…

Categorical ERP Repetition Effects for Human and Furniture Items in 7-Month-Old Infants

ERIC Educational Resources Information Center

Peykarjou, Stefanie; Wissner, Julia; Pauen, Sabina

2017-01-01

Behavioural and recent neural evidence indicates that young infants discriminate broad stimulus categories. However, little is known about the categorical perception of humans represented as full bodies with heads and their discrimination from inanimate objects. This study compares infants' brain processing of human and furniture pictures, probing…

The Readiness of Schools in Zimbabwe for the Implementation of Early Childhood Education

ERIC Educational Resources Information Center

Mangwaya, Ezron; Blignaut, Sylvan; Pillay, Shervani K.

2016-01-01

This qualitative study focuses on primary schools' state of readiness for the introduction of early childhood education. Adopting a multiple case study design, the article explores, through semi-structured interviews and documentation, school heads, teachers-in-charge and classroom teachers' perceptions of their respective schools' state of…

Job Satisfaction: Factor Analysis of Greek Primary School Principals' Perceptions

ERIC Educational Resources Information Center

Saiti, Anna; Fassoulis, Konstantinos

2012-01-01

Purpose: The purpose of this paper is to investigate the factors that affect the level of job satisfaction that school principals experience and, based on the findings, to suggest policies or techniques for improving it. Design/methodology/approach: Questionnaires were administered to 180 primary school heads in 13 prefectures--one from each of…

Athletes' Perceptions of Coaching Competency Scale II-High School Teams

ERIC Educational Resources Information Center

Myers, Nicholas D.; Chase, Melissa A.; Beauchamp, Mark R.; Jackson, Ben

2010-01-01

The purpose of this validity study was to improve measurement of athletes' evaluations of their head coach's coaching competency, an important multidimensional construct in models of coaching effectiveness. A revised version of the Coaching Competency Scale (CCS) was developed for athletes of high school teams (APCCS II-HST). Data were collected…

Brain Mechanisms Involved in Early Visual Perception.

ERIC Educational Resources Information Center

Karmel, Bernard Z.

This document presents an analysis of the early attending responses and orienting reactions of infants which can be observed at birth and shortly thereafter. Focus is on one specific orienting reaction, the early direction and maintenance of one's eyes and head toward certain stimuli instead of others. The physical properties of stimuli that…

An Intraocular Camera for Retinal Prostheses: Restoring Sight to the Blind

NASA Astrophysics Data System (ADS)

Stiles, Noelle R. B.; McIntosh, Benjamin P.; Nasiatka, Patrick J.; Hauer, Michelle C.; Weiland, James D.; Humayun, Mark S.; Tanguay, Armand R., Jr.

Implantation of an intraocular retinal prosthesis represents one possible approach to the restoration of sight in those with minimal light perception due to photoreceptor degenerating diseases such as retinitis pigmentosa and age-related macular degeneration. In such an intraocular retinal prosthesis, a microstimulator array attached to the retina is used to electrically stimulate still-viable retinal ganglion cells that transmit retinotopic image information to the visual cortex by means of the optic nerve, thereby creating an image percept. We describe herein an intraocular camera that is designed to be implanted in the crystalline lens sac and connected to the microstimulator array. Replacement of an extraocular (head-mounted) camera with the intraocular camera restores the natural coupling of head and eye motion associated with foveation, thereby enhancing visual acquisition, navigation, and mobility tasks. This research is in no small part inspired by the unique scientific style and research methodologies that many of us have learned from Prof. Richard K. Chang of Yale University, and is included herein as an example of the extent and breadth of his impact and legacy.

The oblique effect is both allocentric and egocentric

PubMed Central

Mikellidou, Kyriaki; Cicchini, Guido Marco; Thompson, Peter G.; Burr, David C.

2016-01-01

Despite continuous movements of the head, humans maintain a stable representation of the visual world, which seems to remain always upright. The mechanisms behind this stability are largely unknown. To gain some insight on how head tilt affects visual perception, we investigate whether a well-known orientation-dependent visual phenomenon, the oblique effect—superior performance for stimuli at cardinal orientations (0° and 90°) compared with oblique orientations (45°)—is anchored in egocentric or allocentric coordinates. To this aim, we measured orientation discrimination thresholds at various orientations for different head positions both in body upright and in supine positions. We report that, in the body upright position, the oblique effect remains anchored in allocentric coordinates irrespective of head position. When lying supine, gravitational effects in the plane orthogonal to gravity are discounted. Under these conditions, the oblique effect was less marked than when upright, and anchored in egocentric coordinates. The results are well explained by a simple “compulsory fusion” model in which the head-based and the gravity-based signals are combined with different weightings (30% and 70%, respectively), even when this leads to reduced sensitivity in orientation discrimination. PMID:26129862

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2010 CFR

2010-10-01

....2, S4.4 or S4.5 of this section. S4.2Except for school buses, a head restraint that conforms to... position. For school buses, a head restraint that conforms to either S4.2 (a) or (b) of this section must... one of the following occurs: (i) Failure of the seat or seat back; or, (ii) Application of a load of...

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2011 CFR

2011-10-01

....2, S4.4 or S4.5 of this section. S4.2Except for school buses, a head restraint that conforms to... position. For school buses, a head restraint that conforms to either S4.2 (a) or (b) of this section must... one of the following occurs: (i) Failure of the seat or seat back; or, (ii) Application of a load of...

Topical ivermectin 0.5% lotion for treatment of head lice.

PubMed

Deeks, Louise S; Naunton, Mark; Currie, Marian J; Bowden, Francis J

2013-09-01

To investigate the pharmacology, pharmacokinetics, efficacy, adverse effects, and place in therapy of a single application of topical ivermectin 0.5% lotion for head lice treatment. Literature was obtained by searching MEDLINE, PubMed, CINAHL, and Scopus (January 1980 to January 2013). Abstracts were searched for the terms ivermectin AND (head lice or pediculus or pediculosis), topical ivermectin, ivermectin lotion, ivermectin AND (pharmacology OR pharmacokinetics). The New Drug Application filed with the Food and Drug Administration and the product data sheets for ivermectin were obtained. All English-language articles retrieved from the search were evaluated for relevance to the objective. The recommended first-line head lice treatments in the United States are permethrin 1% or pyrethrins, with malathion 0.5% lotion used as a second-line treatment. Significantly more of the 289 head lice-infested participants using topical ivermectin 0.5% lotion were lice-free at day 15 when compared with vehicle control (73.8% vs 17.6%; P < .001) in 2 studies. Although this rate is lower than other third-line treatments (eg, spinosad 0.9% or benzyl alcohol 5%), topical ivermectin 0.5% lotion is well tolerated (pruritus, the most common adverse event, 0.9%) and requires only a single application. Topical ivermectin 0.5% lotion kills head lice by increasing chloride in muscle cells, causing hyperpolarization and paralysis. Only 1 application is required; when the treated eggs hatch, the lice are not viable because they cannot feed as a result of pharyngeal muscle paralysis. Minimal systemic absorption occurs following topical application. Studies have demonstrated that topical ivermectin 0.5% is a safe and efficacious treatment for head lice. Although it has no documented resistance, there is limited clinical experience, it requires a prescription, and it is expensive. Therefore it should be reserved as a third-line treatment for head lice in the United States.

Design and fabrication of a realistic anthropomorphic heterogeneous head phantom for MR purposes

PubMed Central

Wood, Sossena; Krishnamurthy, Narayanan; Santini, Tales; Raval, Shailesh; Farhat, Nadim; Holmes, John Andy; Ibrahim, Tamer S.

2017-01-01

Objective The purpose of this study is to design an anthropomorphic heterogeneous head phantom that can be used for MRI and other electromagnetic applications. Materials and methods An eight compartment, physical anthropomorphic head phantom was developed from a 3T MRI dataset of a healthy male. The designed phantom was successfully built and preliminarily evaluated through an application that involves electromagnetic-tissue interactions: MRI (due to it being an available resource). The developed phantom was filled with media possessing electromagnetic constitutive parameters that correspond to biological tissues at ~297 MHz. A preliminary comparison between an in-vivo human volunteer (based on whom the anthropomorphic head phantom was created) and various phantoms types, one being the anthropomorphic heterogeneous head phantom, were performed using a 7 Tesla human MRI scanner. Results Echo planar imaging was performed and minimal ghosting and fluctuations were observed using the proposed anthropomorphic phantom. The magnetic field distributions (during MRI experiments at 7 Tesla) and the scattering parameter (measured using a network analyzer) were most comparable between the anthropomorphic heterogeneous head phantom and an in-vivo human volunteer. Conclusion The developed anthropomorphic heterogeneous head phantom can be used as a resource to various researchers in applications that involve electromagnetic-biological tissue interactions such as MRI. PMID:28806768

Where is straight ahead to a patient with unilateral vestibular loss?

PubMed

Saj, Arnaud; Honoré, Jacques; Bernard-Demanze, Laurence; Devèze, Arnaud; Magnan, Jacques; Borel, Liliane

2013-05-01

The vestibular system is classically associated with postural control, oculomotor reflexes and self-motion perception. The patients with vestibular loss are primarily concerned with balance and gait problems including head and trunk tilt and walking trajectory deviation to the lesioned side. These long-lasting postural and locomotor biases are thought to originate from changes in spatial perception of self. Indeed, we show here that vestibular cues are necessary for an accurate representation of body orientation. Patients with right (RVN; n=11) or left vestibular neurotomy (LVN; 9) as a treatment for Menière's disease were compared with 10 healthy controls. The subjective straight ahead (SSA) was investigated using a method disentangling lateral shift and tilt components of error. In the horizontal plane, subjects were required to align a rod with their body midline. In the frontal plane, they were asked to align the rod with the midline of head or trunk. The analysis of SSA clearly showed distinct results according to the side of the lesion. The LVN patients had a contralesional lateral shift of SSA. In addition, they showed an ipsilesional tilt, more severe for the head than for the trunk. By contrast, in RVN patients, the representation of the body midline was fairly accurate in both the horizontal and frontal planes and did not differ from that of control subjects. The present study shows deviations in body orientation representation after unilateral vestibular loss. Deviations are observed in the horizontal as well as in the frontal planes. Interestingly, only patients with left vestibular loss were concerned with these changes in perception of self-orientation in space. These data support the hypothesis of an asymmetric vestibular function in healthy subjects and confirm the similarity of functional disorders in patients with vestibular deficits or spatial neglect. For the first time, this similarity is found at the level of body representation. Copyright © 2012 Elsevier Ltd. All rights reserved.

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2014 CFR

2014-10-01

... seat back; or, (ii) Application of a load of 890N. S4.3[Reserved] S4.4.Except for school buses, a head... comply with, at the manufacturer's option, S4.2, S4.4 or S4.5 of this section. S4.2Except for school... outboard front designated seating position. For school buses, a head restraint that conforms to either S4.2...

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2013 CFR

2013-10-01

... seat back; or, (ii) Application of a load of 890N. S4.3[Reserved] S4.4.Except for school buses, a head... comply with, at the manufacturer's option, S4.2, S4.4 or S4.5 of this section. S4.2Except for school... outboard front designated seating position. For school buses, a head restraint that conforms to either S4.2...

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2012 CFR

2012-10-01

... seat back; or, (ii) Application of a load of 890N. S4.3[Reserved] S4.4.Except for school buses, a head... comply with, at the manufacturer's option, S4.2, S4.4 or S4.5 of this section. S4.2Except for school... outboard front designated seating position. For school buses, a head restraint that conforms to either S4.2...

Emergency Physician Attitudes, Preferences, and Risk Tolerance for Stroke as a Potential Cause of Dizziness Symptoms

PubMed Central

Kene, Mamata V.; Ballard, Dustin W.; Vinson, David R.; Rauchwerger, Adina S.; Iskin, Hilary R.; Kim, Anthony S.

2015-01-01

Introduction We evaluated emergency physicians’ (EP) current perceptions, practice, and attitudes towards evaluating stroke as a cause of dizziness among emergency department patients. Methods We administered a survey to all EPs in a large integrated healthcare delivery system. The survey included clinical vignettes, perceived utility of historical and exam elements, attitudes about the value of and requisite post-test probability of a clinical prediction rule for dizziness. We calculated descriptive statistics and post-test probabilities for such a clinical prediction rule. Results The response rate was 68% (366/535). Respondents’ median practice tenure was eight years (37% female, 92% emergency medicine board certified). Symptom quality and typical vascular risk factors increased suspicion for stroke as a cause of dizziness. Most respondents reported obtaining head computed tomography (CT) (74%). Nearly all respondents used and felt confident using cranial nerve and limb strength testing. A substantial minority of EPs used the Epley maneuver (49%) and HINTS (head-thrust test, gaze-evoked nystagmus, and skew deviation) testing (30%); however, few EPs reported confidence in these tests’ bedside application (35% and 16%, respectively). Respondents favorably viewed applying a properly validated clinical prediction rule for assessment of immediate and 30-day stroke risk, but indicated it would have to reduce stroke risk to <0.5% to be clinically useful. Conclusion EPs report relying on symptom quality, vascular risk factors, simple physical exam elements, and head CT to diagnose stroke as the cause of dizziness, but would find a validated clinical prediction rule for dizziness helpful. A clinical prediction rule would have to achieve a 0.5% post-test stroke probability for acceptability. PMID:26587108

Integration of vestibular and head movement signals in the vestibular nuclei during whole-body rotation

NASA Technical Reports Server (NTRS)

Gdowski, G. T.; McCrea, R. A.; Peterson, B. W. (Principal Investigator)

1999-01-01

Single-unit recordings were obtained from 107 horizontal semicircular canal-related central vestibular neurons in three alert squirrel monkeys during passive sinusoidal whole-body rotation (WBR) while the head was free to move in the yaw plane (2.3 Hz, 20 degrees /s). Most of the units were identified as secondary vestibular neurons by electrical stimulation of the ipsilateral vestibular nerve (61/80 tested). Both non-eye-movement (n = 52) and eye-movement-related (n = 55) units were studied. Unit responses recorded when the head was free to move were compared with responses recorded when the head was restrained from moving. WBR in the absence of a visual target evoked a compensatory vestibulocollic reflex (VCR) that effectively reduced the head velocity in space by an average of 33 +/- 14%. In 73 units, the compensatory head movements were sufficiently large to permit the effect of the VCR on vestibular signal processing to be assessed quantitatively. The VCR affected the rotational responses of different vestibular neurons in different ways. Approximately one-half of the units (34/73, 47%) had responses that decreased as head velocity decreased. However, the responses of many other units (24/73) showed little change. These cells had signals that were better correlated with trunk velocity than with head velocity. The remaining units had responses that were significantly larger (15/73, 21%) when the VCR produced a decrease in head velocity. Eye-movement-related units tended to have rotational responses that were correlated with head velocity. On the other hand, non-eye-movement units tended to have rotational responses that were better correlated with trunk velocity. We conclude that sensory vestibular signals are transformed from head-in-space coordinates to trunk-in-space coordinates on many secondary vestibular neurons in the vestibular nuclei by the addition of inputs related to head rotation on the trunk. This coordinate transformation is presumably important for controlling postural reflexes and constructing a central percept of body orientation and movement in space.

Neck Proprioception Shapes Body Orientation and Perception of Motion

PubMed Central

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. PMID:25414660

Neck proprioception shapes body orientation and perception of motion.

PubMed

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.

Internalized elevation perception of simple stimuli in cochlear-implant and normal-hearing listeners

PubMed Central

Thakkar, Tanvi; Goupell, Matthew J.

2014-01-01

In normal-hearing (NH) listeners, elevation perception is produced by the spectral cues imposed by the pinna, head, and torso. Elevation perception in cochlear-implant (CI) listeners appears to be non-existent; this may be a result of poorly encoded spectral cues. In this study, an analog of elevation perception was investigated by having 15 CI and 8 NH listeners report the intracranial location of spectrally simple signals (single-electrode or bandlimited acoustic stimuli, respectively) in both horizontal and vertical dimensions. Thirteen CI listeners and all of the NH listeners showed an association between place of stimulation (i.e., stimulus frequency) and perceived elevation, generally responding with higher elevations for more basal stimulation. This association persisted in the presence of a randomized temporal pitch, suggesting that listeners were not associating pitch with elevation. These data provide evidence that CI listeners might perceive changes in elevation if they were presented stimuli with sufficiently salient elevation cues. PMID:25096117

Auditory compensation for head rotation is incomplete.

PubMed

Freeman, Tom C A; Culling, John F; Akeroyd, Michael A; Brimijoin, W Owen

2017-02-01

Hearing is confronted by a similar problem to vision when the observer moves. The image motion that is created remains ambiguous until the observer knows the velocity of eye and/or head. One way the visual system solves this problem is to use motor commands, proprioception, and vestibular information. These "extraretinal signals" compensate for self-movement, converting image motion into head-centered coordinates, although not always perfectly. We investigated whether the auditory system also transforms coordinates by examining the degree of compensation for head rotation when judging a moving sound. Real-time recordings of head motion were used to change the "movement gain" relating head movement to source movement across a loudspeaker array. We then determined psychophysically the gain that corresponded to a perceptually stationary source. Experiment 1 showed that the gain was small and positive for a wide range of trained head speeds. Hence, listeners perceived a stationary source as moving slightly opposite to the head rotation, in much the same way that observers see stationary visual objects move against a smooth pursuit eye movement. Experiment 2 showed the degree of compensation remained the same for sounds presented at different azimuths, although the precision of performance declined when the sound was eccentric. We discuss two possible explanations for incomplete compensation, one based on differences in the accuracy of signals encoding image motion and self-movement and one concerning statistical optimization that sacrifices accuracy for precision. We then consider the degree to which such explanations can be applied to auditory motion perception in moving listeners. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Behavioural evidence for a visual and proprioceptive control of head roll in hoverflies (Episyrphus balteatus).

PubMed

Goulard, Roman; Julien-Laferriere, Alice; Fleuriet, Jérome; Vercher, Jean-Louis; Viollet, Stéphane

2015-12-01

The ability of hoverflies to control their head orientation with respect to their body contributes importantly to their agility and their autonomous navigation abilities. Many tasks performed by this insect during flight, especially while hovering, involve a head stabilization reflex. This reflex, which is mediated by multisensory channels, prevents the visual processing from being disturbed by motion blur and maintains a consistent perception of the visual environment. The so-called dorsal light response (DLR) is another head control reflex, which makes insects sensitive to the brightest part of the visual field. In this study, we experimentally validate and quantify the control loop driving the head roll with respect to the horizon in hoverflies. The new approach developed here consisted of using an upside-down horizon in a body roll paradigm. In this unusual configuration, tethered flying hoverflies surprisingly no longer use purely vision-based control for head stabilization. These results shed new light on the role of neck proprioceptor organs in head and body stabilization with respect to the horizon. Based on the responses obtained with male and female hoverflies, an improved model was then developed in which the output signals delivered by the neck proprioceptor organs are combined with the visual error in the estimated position of the body roll. An internal estimation of the body roll angle with respect to the horizon might explain the extremely accurate flight performances achieved by some hovering insects. © 2015. Published by The Company of Biologists Ltd.

Classroom-Based Interventions and Teachers' Perceived Job Stressors and Confidence: Evidence from a Randomized Trial in Head Start Settings

ERIC Educational Resources Information Center

Zhai, Fuhua; Raver, C. Cybele; Li-Grining, Christine

2011-01-01

Preschool teachers' job stressors have received increasing attention but have been understudied in the literature. We investigated the impacts of a classroom-based intervention, the Chicago School Readiness Project (CSRP), on teachers' perceived job stressors and confidence, as indexed by their perceptions of job control, job resources, job…

Perceptions of General Education Deans and Department Chairs of Their Colleges as Learning Organizations

ERIC Educational Resources Information Center

Mulligan, May Charmayne

2014-01-01

Higher education institutions are being pushed towards increased assessment practices because of rising costs, mass access, new delivery methods, and rising competition on the national and global scale. Academic deans and department heads are at the center of these assessment efforts, and assessment should guide changes within the organization for…

The Maternal Role in Promoting Emotional Competence: Predicting Head Start Mothers' Expressiveness, Perceived Role, and Receptivity to Support

ERIC Educational Resources Information Center

Edwards, Nicole Megan

2010-01-01

Guided by Bioecological Systems Theory and Schema Theory, I investigated mothers' perceptions regarding the emotional development of their preschool children. Researchers acknowledge mothers' contributing role in influencing children's behavioral displays of emotion, but there is a dearth in the literature on mothers. emotion-related behaviors,…

Teacher Perceptions of Head Start Preschool Programs in an Urban Public School District

ERIC Educational Resources Information Center

Perez, Salvador

2017-01-01

An initiative to coordinate early learning programs across a major city in the Midwestern United States was undertaken in 2013. The opinions of teachers regarding effects on instruction and children were not included in the development and implementation of the program. This omission is important because multiple scholars have pointed to the…

Preservice Elementary Teachers' Perceptions of Family: Considering Future Instruction on Lesbian- and Gay-Headed Families

ERIC Educational Resources Information Center

Larrabee, Timothy G.; Kim, Youngjoo

2010-01-01

Sixty-eight preservice teachers from a midwestern university responded to a questionnaire asking the construct of their family, their definition of "family", if they recognized 18 relationships as families, and if they would use those relationships as examples in their future teaching. We focus primarily on participants' responses to examples of…

Audiovisual Perception of Noise Vocoded Speech in Dyslexic and Non-Dyslexic Adults: The Role of Low-Frequency Visual Modulations

ERIC Educational Resources Information Center

Megnin-Viggars, Odette; Goswami, Usha

2013-01-01

Visual speech inputs can enhance auditory speech information, particularly in noisy or degraded conditions. The natural statistics of audiovisual speech highlight the temporal correspondence between visual and auditory prosody, with lip, jaw, cheek and head movements conveying information about the speech envelope. Low-frequency spatial and…

Head Start Classroom Teachers' and Assistant Teachers' Perceptions of Professional Development Using a Learn Framework

ERIC Educational Resources Information Center

Nasser, Ilham; Kidd, Julie K.; Burns, M. Susan; Campbell, Trina

2015-01-01

This study investigates early childhood education teachers' and assistant teachers' views about a year-long professional development model that focuses on developing intentional teaching. The study shares the results of interviews conducted with the teachers at the end of the implementation of a one-year experimental professional model in Head…

Sensorimotor Integration for Decision Making: How the Worm Steers.

PubMed

Kaplan, Harris S; Zimmer, Manuel

2018-01-17

Animals' movements actively shape their perception and subsequent decision making. In this issue of Neuron, Liu et al. (2018) show how C. elegans nematodes steer toward an odorant: a dedicated interneuron class integrates oscillatory olfactory signals, generated by head swings, with corollary discharge motor signals. Copyright © 2017 Elsevier Inc. All rights reserved.

Evoking Hearts and Heads: Exploring Issues of Social Justice through Poetry

ERIC Educational Resources Information Center

Damico, James S.

2005-01-01

In this article, the author relates the effectiveness of using poetry in his classroom. He relates how students who initially thought poetry as "sappy" have somehow changed their perceptions as they begin to learn more about it. Through various poems, these students came to see how poetry can be a catalyst for a provocative inquiry…

Metaphors and Drawings as Research Tools of Head Teachers' Perceptions on Their Management and Leadership Roles and Responsibilities

ERIC Educational Resources Information Center

Argyropoulou, Eleftheria; Hatira, Kalliopi

2014-01-01

This article introduces an alternative qualitative research tool: metaphor and drawing, as projections of personality features, to explore underlying concepts and values, thoughts and beliefs, fears and hesitations, aspirations and ambitions of the research subjects. These two projective tools are used to explore Greek state kindergarten head…

The Music Co-ordinator in the Primary School

ERIC Educational Resources Information Center

Button, Stuart; Potter, Allison

2006-01-01

This article reports on the results of a study which investigated teachers' and head teachers' perceptions of the role of the music co-ordinator in the primary school, and provides insight into how the role might be made more effective. The teachers participating in this project were chosen from twenty primary schools from one local educational…

Teachers' Language in Interactions: An Exploratory Examination of Mental State Talk in Early Childhood Education Classrooms

ERIC Educational Resources Information Center

King, Elizabeth; La Paro, Karen

2015-01-01

Research Findings: This study examined 34 Head Start teachers' use of four categories of mental state talk (verbalizations of mental processes using emotion terms, cognition terms, desire terms, and perception terms) during naturally occurring classroom interactions. Transcriptions from classroom videos were coded for mental state talk…

In the blink of an eye: head mounted displays development within BAE Systems

NASA Astrophysics Data System (ADS)

Cameron, Alex

2015-05-01

There has been an explosion of interest in head worn displays in recent years, particularly for consumer applications with an attendant ramping up of investment into key enabling technologies to provide what is essence a mobile computer display. However, head mounted system have been around for over 40 years and today's consumer products are building on a legacy of knowledge and technology created by companies such as BAE Systems who have been designing and fielding helmet mounted displays (HMD) for a wide range of specialist applications. Although the dominant application area has been military aviation, solutions have been fielded for solider, ground vehicle, simulation, medical, racing car and even subsea navigation applications. What sets these HMDs apart is that they provide the user with accurate conformal information embedded in the users real world view where the information presented is intuitive and easy to use because it overlays the real world and enables them to stay head up, eyes out, - improving their effectiveness, reducing workload and improving safety. Such systems are an enabling technology in the provision of enhanced Situation Awareness (SA) and reducing user workload in high intensity situations. These capabilities are finding much wider application in new types of compact man mounted audio/visual products enabled by the emergence of new families of micro displays, novel optical concepts and ultra-compact low power processing solutions. This paper therefore provides a personal summary of BAE Systems 40 year's journey in developing and fielding Head Mounted systems, their applications.

The Hologram in My Hand: How Effective is Interactive Exploration of 3D Visualizations in Immersive Tangible Augmented Reality?

PubMed

Bach, Benjamin; Sicat, Ronell; Beyer, Johanna; Cordeil, Maxime; Pfister, Hanspeter

2018-01-01

We report on a controlled user study comparing three visualization environments for common 3D exploration. Our environments differ in how they exploit natural human perception and interaction capabilities. We compare an augmented-reality head-mounted display (Microsoft HoloLens), a handheld tablet, and a desktop setup. The novel head-mounted HoloLens display projects stereoscopic images of virtual content into a user's real world and allows for interaction in-situ at the spatial position of the 3D hologram. The tablet is able to interact with 3D content through touch, spatial positioning, and tangible markers, however, 3D content is still presented on a 2D surface. Our hypothesis is that visualization environments that match human perceptual and interaction capabilities better to the task at hand improve understanding of 3D visualizations. To better understand the space of display and interaction modalities in visualization environments, we first propose a classification based on three dimensions: perception, interaction, and the spatial and cognitive proximity of the two. Each technique in our study is located at a different position along these three dimensions. We asked 15 participants to perform four tasks, each task having different levels of difficulty for both spatial perception and degrees of freedom for interaction. Our results show that each of the tested environments is more effective for certain tasks, but that generally the desktop environment is still fastest and most precise in almost all cases.

Student Perceptions of iPad Applications-Assisted Instruction in Health Professions Education.

PubMed

Little, Ross M; Colligan, Amanda; Broyles, India

2016-01-01

The purpose of this study was to examine student's perceptions of the iPad applications-assisted instruction as part of their learning. In this study, multiple features and applications were evaluated as an instructional tool. Fifteen participants responded to the survey indicating their perceptions of the iPad and applications used as part of their course delivery. Overall, participants favored the use of this technology as an instructional tool in their learning and indicated several aspects that could be improved.

Augmentation of blood circulation to the fingers by warming distant body areas

NASA Technical Reports Server (NTRS)

Koscheyev, V. S.; Leon, G. R.; Paul, S.; Tranchida, D.; Linder, I. V.

2000-01-01

Future activities in space will require greater periods of time in extreme environments in which the body periphery will be vulnerable to chilling. Maintaining the hands and fingers in comfortable conditions enhances finger flexibility and dexterity, and thus effects better work performance. We have evaluated the efficacy of promoting heat transfer and release by the extremities by increasing the blood flow to the periphery from more distant parts of the body. The experimental garment paradigm developed by the investigators was used to manipulate the temperature of different body areas. Six subjects, two females and four males, were evaluated in a stage-1 baseline condition, with the inlet temperature of the circulating water in the liquid cooling/warming garment (LCWG) at 33 degrees C. At stage 2 the total LCWG water inlet temperature was cooled to 8 degrees C, and at stage 3 the inlet water temperature in specific segments of the LCWG was warmed (according to protocol) to 45 degrees C, while the inlet temperature in the rest of the LCWG was maintained at 8 degrees C. The following four body-area-warming conditions were studied in separate sessions: (1) head, (2) upper torso/arm, (3) upper torso/arm/head, and (4) legs/feet. Skin temperature, heat flux and blood perfusion of the fingers, and subjective perception of thermal sensations and overall physical comfort were assessed. Finger temperature (T(fing)) analyses showed a statistically significant condition x stage interaction. Post-hoc comparisons (T(fing)) indicated that at stage 3, the upper torso/arm/head warming condition was significantly different from the head, upper torso/arm and legs/feet conditions, showing an increase in T(fing). There was a significant increase in blood perfusion in the fingers at stage 3 in all conditions. Subjective perception of hand warmth, and overall physical comfort level significantly increased in the stage 3 upper torso/arm/head condition. The findings indicate that physiological methods to enhance heat transfer by the blood to the periphery within protective clothing provide an additional tool for increasing total and local human comfort in extreme environments.

Pediatric Minor Head Injury 2.0: Moving from Injury Exclusion to Risk Stratification.

PubMed

Homme, James Jim L

2018-05-01

Visits for pediatric minor blunt head trauma continue to increase. Variability exists in clinician evaluation and management of this generally low-risk population. Clinical decision rules identify very low-risk children who can forgo neuroimaging. Observation before imaging decreases neuroimaging rates. Outcome data can be used to risk stratify children into more discrete categories. Decision aids improves knowledge and accuracy of risk perception and facilitates identification of caregiver preferences, allowing for shared decision making. For children in whom imaging is performed and is normal or shows isolated linear skull fractures, deterioration and neurosurgical intervention are rare and hospital admission can be avoided. Copyright © 2018 The Author. Published by Elsevier Inc. All rights reserved.

Post interaural neural net-based vowel recognition

NASA Astrophysics Data System (ADS)

Jouny, Ismail I.

2001-10-01

Interaural head related transfer functions are used to process speech signatures prior to neural net based recognition. Data representing the head related transfer function of a dummy has been collected at MIT and made available on the Internet. This data is used to pre-process vowel signatures to mimic the effects of human ear on speech perception. Signatures representing various vowels of the English language are then presented to a multi-layer perceptron trained using the back propagation algorithm for recognition purposes. The focus in this paper is to assess the effects of human interaural system on vowel recognition performance particularly when using a classification system that mimics the human brain such as a neural net.

Application of the capsaicin 8% cutaneous patch in neuropathic pain of the head and face: A case series.

PubMed

Gaul, Charly; Resch, Sonja

2015-05-01

Treatment of neuropathic or neuralgic head and facial pain due to dental, traumatic or surgical nerve lesions or post-herpetic neuropathy is often challenging. We are reporting on four patients with neuropathic pain syndromes successfully treated with a capsaicin 8% patch in the affected area of the head or face. Treatment with the capsaicin 8% patch seems to be effective and safe for application to the facial and head region. The capsaicin 8% patch might be an additional treatment option if first-line treatment with anticonvulsants or antidepressants was ineffective or limited by side effects. © International Headache Society 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Electron Microscopic Recording of the Power and Recovery Strokes of Individual Myosin Heads Coupled with ATP Hydrolysis: Facts and Implications.

PubMed

Sugi, Haruo; Chaen, Shigeru; Akimoto, Tsuyoshi

2018-05-04

The most straightforward way to get information on the performance of individual myosin heads producing muscle contraction may be to record their movement, coupled with ATP hydrolysis, electron-microscopically using the gas environmental chamber (EC). The EC enables us to visualize and record ATP-induced myosin head movement in hydrated skeletal muscle myosin filaments. When actin filaments are absent, myosin heads fluctuate around a definite neutral position, so that their time-averaged mean position remains unchanged. On application of ATP, myosin heads are found to move away from, but not towards, the bare region, indicating that myosin heads perform a recovery stroke (average amplitude, 6 nm). After exhaustion of ATP, myosin heads return to their neutral position. In the actin⁻myosin filament mixture, myosin heads form rigor actin myosin linkages, and on application of ATP, they perform a power stroke by stretching adjacent elastic structures because of a limited amount of applied ATP ≤ 10 µM. The average amplitude of the power stroke is 3.3 nm and 2.5 nm at the distal and the proximal regions of the myosin head catalytic domain (CAD), respectively. The power stroke amplitude increases appreciably at low ionic strength, which is known to enhance Ca 2+ -activated force in muscle. In both the power and recovery strokes, myosin heads return to their neutral position after exhaustion of ATP.

Visual–Motor Transformations Within Frontal Eye Fields During Head-Unrestrained Gaze Shifts in the Monkey

PubMed Central

Sajad, Amirsaman; Sadeh, Morteza; Keith, Gerald P.; Yan, Xiaogang; Wang, Hongying; Crawford, John Douglas

2015-01-01

A fundamental question in sensorimotor control concerns the transformation of spatial signals from the retina into eye and head motor commands required for accurate gaze shifts. Here, we investigated these transformations by identifying the spatial codes embedded in visually evoked and movement-related responses in the frontal eye fields (FEFs) during head-unrestrained gaze shifts. Monkeys made delayed gaze shifts to the remembered location of briefly presented visual stimuli, with delay serving to dissociate visual and movement responses. A statistical analysis of nonparametric model fits to response field data from 57 neurons (38 with visual and 49 with movement activities) eliminated most effector-specific, head-fixed, and space-fixed models, but confirmed the dominance of eye-centered codes observed in head-restrained studies. More importantly, the visual response encoded target location, whereas the movement response mainly encoded the final position of the imminent gaze shift (including gaze errors). This spatiotemporal distinction between target and gaze coding was present not only at the population level, but even at the single-cell level. We propose that an imperfect visual–motor transformation occurs during the brief memory interval between perception and action, and further transformations from the FEF's eye-centered gaze motor code to effector-specific codes in motor frames occur downstream in the subcortical areas. PMID:25491118

The Noh mask effect: vertical viewpoint dependence of facial expression perception.

PubMed Central

Lyons, M J; Campbell, R; Plante, A; Coleman, M; Kamachi, M; Akamatsu, S

2000-01-01

Full-face masks, worn by skilled actors in the Noh tradition, can induce a variety of perceived expressions with changes in head orientation. Out-of-plane rotation of the head changes the two-dimensional image characteristics of the face which viewers may misinterpret as non-rigid changes due to muscle action. Three experiments with Japanese and British viewers explored this effect. Experiment 1 confirmed a systematic relationship between vertical angle of view of a Noh mask and judged affect. A forward tilted mask was more often judged happy, and one backward tilted more often judged sad. This effect was moderated by culture. Japanese viewers ascribed happiness to the mask at greater degrees of backward tilt with a reversal towards sadness at extreme forward angles. Cropping the facial image of chin and upper head contour reduced the forward-tilt reversal. Finally, the relationship between head tilt and affect was replicated with a laser-scanned human face image, but with no cultural effect. Vertical orientation of the head changes the apparent disposition of facial features and viewers respond systematically to these changes. Culture moderates this effect, and we discuss how perceptual strategies for ascribing expression to familiar and unfamiliar images may account for the differences. PMID:11413638

Leadership styles in ethical dilemmas when head nurses make decisions.

PubMed

Zydziunaite, V; Lepaite, D; Suominen, T

2013-06-01

The overlooked aspect in Lithuania is the dearth of leaders among head nurses, who bear the responsibility for decisions in ethical dilemmas. Understanding the application of leadership styles is fundamental to ensuring head nurses' abilities to influence outcomes for healthcare providers and patients. To identify the leadership styles applied by head nurses in decision making in ethical dilemmas on hospital wards. The data were collected by questionnaires completed by head nurses (n = 278) working in five major state-funded hospitals in each of the five regions of Lithuania. The data were analysed using SPSS 16.0, calculating descriptive statistics and analysis of variance. Head nurses apply democratic, affiliative, transformational and sustainable leadership styles when resolving ethical dilemmas. The application of leadership styles is associated not only with specific situations, but also with certain background factors, such as years of experience in a head nurse's position, ward specialization and the incidence of ethical dilemmas. Nurses having been in a head nurse's position over 10 years use primitive leadership styles, notably bureaucratic leadership, more often than do those head nurses with only a few years of experience in such a position. The results highlight the need for head nurses to reflect on their practices and to find new ways of learning from practice, colleagues and patients. Head nurses' managerial decisions due to their 'executive power' can turn into a new state-of-the-art leadership in nursing. © 2013 The Authors. International Nursing Review © 2013 International Council of Nurses.

Use of cues in virtual reality depends on visual feedback.

PubMed

Fulvio, Jacqueline M; Rokers, Bas

2017-11-22

3D motion perception is of central importance to daily life. However, when tested in laboratory settings, sensitivity to 3D motion signals is found to be poor, leading to the view that heuristics and prior assumptions are critical for 3D motion perception. Here we explore an alternative: sensitivity to 3D motion signals is context-dependent and must be learned based on explicit visual feedback in novel environments. The need for action-contingent visual feedback is well-established in the developmental literature. For example, young kittens that are passively moved through an environment, but unable to move through it themselves, fail to develop accurate depth perception. We find that these principles also obtain in adult human perception. Observers that do not experience visual consequences of their actions fail to develop accurate 3D motion perception in a virtual reality environment, even after prolonged exposure. By contrast, observers that experience the consequences of their actions improve performance based on available sensory cues to 3D motion. Specifically, we find that observers learn to exploit the small motion parallax cues provided by head jitter. Our findings advance understanding of human 3D motion processing and form a foundation for future study of perception in virtual and natural 3D environments.

Whole-School Management Issues Concerning the PE Department: "A Natural Division of Labour?"

ERIC Educational Resources Information Center

Williams, Gareth Mark; Williams, Dean

2013-01-01

Utilising the labour ideas of Adam Smith and Emile Durkheim as a theoretical basis, the main objective of this study was to investigate the perception that Heads of Physical Education (HoPE) face unique management and leadership challenges. Results showed that HoPE believe that they are overburdened with tasks primarily involving the delegation of…

Determining the Turkish World Perceptions of Candidate Social Studies Teachers through Word Association Test

ERIC Educational Resources Information Center

Tokcan, Halil

2017-01-01

The purpose of this study is to observe prospective teachers' cognitive structures related to Turkish World. In this scanning model study, WAT (Word Association Test) had been applied to 332 prospective teachers in Nigde Ömer Halisdemir University. And they were asked to write what comes into their heads when it is said Turkish Republics and…

Self and Superior Assessment.

DTIC Science & Technology

1986-06-01

model of the self-evaluation process as it differs from the evaluation process used by superiors. Symbolic Interactionism One view of self assessment is...supplied by the symbolic interactionists (Cooley, 1902; Head, 1934), who state that self perceptions are generated largely from individuals...disagreements remained even immediately after an appraisal interview in which a great deal of feedback was given. Research on the symbolic interactionist

Cultural Differences in Face-ism: Male Politicians Have Bigger Heads in More Gender-Equal Cultures

ERIC Educational Resources Information Center

Konrath, Sara; Au, Josephine; Ramsey, Laura R.

2012-01-01

Women are visually depicted with lower facial prominence than men, with consequences for perceptions of their competence. The current study examines the relationship between the size of this "face-ism" bias (i.e., individual or micro-level sexism) and a number of gender inequality indicators (i.e., institutional or macro-level sexism) at the…

Speculations on the Insights and Perceptions of Professor William E. Warner Regarding the Status of Technology Education and its Future

ERIC Educational Resources Information Center

Buffer, James J., Jr.

2005-01-01

In this article, the author reflects on the historical work and scholarly contributions of Professor William E. Warner, an intellectual genius whose personal and professional energies were devoted to the development and cultivation of industrial arts education. Jerry Striechler challenged the author to "get into Warner's head" and speculate how…

Educating Coaches about Concussion in Sports: Evaluation of the CDC's "Heads Up: Concussion in Youth Sports" Initiative

ERIC Educational Resources Information Center

Covassin, Tracey; Elbin, R. J.; Sarmiento, Kelly

2012-01-01

Background: Concussions remain a serious public health concern. It is important that persons involved in youth sports, particularly coaches, be made aware and educated on the signs and symptoms of concussion. This study assessed the perceptions of youth sport coaches who have received the Centers for Disease Control and Prevention's…

Creating Concussion Management Policy: How School Leaders, Coaches and Parents Can Work Together to Ensure Kids Stay Safer in Sport

ERIC Educational Resources Information Center

Faure, Caroline

2010-01-01

School leaders, parents and coaches are challenged to ensure the safety of athletes participating in interscholastic programs, including concussion management. With an estimated 300,000 sport-related concussions occurring annually in the United States and a public perception that bell ringers are not concussions, many head-injured children are…

Picky Eaters: Relating Parental Perceptions in Fruit and Vegetables Consumption.

ERIC Educational Resources Information Center

Worobey, Harriet S.; Cohen, Sherry; Kempner, Carol; Worobey, John

Although consuming five servings each day of fruits and vegetables has been designed as a national nutritional goal, there have been few studies of fruit and vegetable intake among 3- to 5-year-olds, even though this age group may benefit from nutrition intervention and education. This study examined the views of 55 Head Start families and 75…

Transformational Leadership and Transfer of Teacher Professional Development to the Classroom in the Kuwait Public High School Context

ERIC Educational Resources Information Center

Winokur, Ilene Kay

2013-01-01

The purpose of this study was to examine how teachers' perceptions of transformational leadership behavior of head of department (HOD) as instructional leader related to their motivation to transfer learning through professional development in public high schools in Kuwait. The study also addressed two other training transfer factors: ability to…

Binaural auralization and perceptual verdicality

NASA Technical Reports Server (NTRS)

Begault, Durand R.

1992-01-01

Early reflection patterns calculated from a room design program were filtered with measured head-related transfer functions (HRTFs) within a 'hypothetical auralization system.' With reference to a particular set of room/listener/sound source configurations, the system is shown to produce both perceptible and imperceptible results. The results of this exploratory analysis are illuminating for future design considerations of HRTF-based auralization systems.

Teacher Leaders' Perceptions and Practice of Student Assessment Reform in Hong Kong: A Case Study

ERIC Educational Resources Information Center

Yu, Wai-Ming

2015-01-01

This paper reports a case study of four project schools in the primary school context of Hong Kong. It has investigated how teachers who were assigned subject panel head's and curriculum leader's roles perceived the student assessment reform and how they experimented with new assessment strategies in the school policy and classroom practice. The…

The "Curriculum Challenge": Moving towards the "Storyline" Approach in a Case Study Urban Primary School

ERIC Educational Resources Information Center

Nuttall, Amanda

2016-01-01

This article draws on an inquiry into the design and implementation of the curriculum in a case study urban primary school in the north of England. In response to the introduction of the revised National Curriculum in September 2014, teachers and the school head engaged in a critical discourse around their perceptions of students' attainment and…

Primary School Councils: Organization, Composition and Head Teacher Perceptions and Values

ERIC Educational Resources Information Center

Burnitt, Michael; Gunter, Helen

2013-01-01

School councils have been an integral part of primary school life for the last decade and, despite not being mandatory in England, they are now to be found in the vast majority of primary schools. This research article aims to examine the current position of school councils in terms of their organization, the issues they address and the views held…

Remembering the past and imagining the future

PubMed Central

Byrne, Patrick; Becker, Suzanna; Burgess, Neil

2009-01-01

The neural mechanisms underlying spatial cognition are modelled, integrating neuronal, systems and behavioural data, and addressing the relationships between long-term memory, short-term memory and imagery, and between egocentric and allocentric and visual and idiothetic representations. Long-term spatial memory is modeled as attractor dynamics within medial-temporal allocentric representations, and short-term memory as egocentric parietal representations driven by perception, retrieval and imagery, and modulated by directed attention. Both encoding and retrieval/ imagery require translation between egocentric and allocentric representations, mediated by posterior parietal and retrosplenial areas and utilizing head direction representations in Papez’s circuit. Thus hippocampus effectively indexes information by real or imagined location, while Papez’s circuit translates to imagery or from perception according to the direction of view. Modulation of this translation by motor efference allows “spatial updating” of representations, while prefrontal simulated motor efference allows mental exploration. The alternating temporo-parietal flows of information are organized by the theta rhythm. Simulations demonstrate the retrieval and updating of familiar spatial scenes, hemispatial neglect in memory, and the effects on hippocampal place cell firing of lesioned head direction representations and of conflicting visual and ideothetic inputs. PMID:17500630

Child Behavior Problems, Teacher Executive Functions, and Teacher Stress in Head Start Classrooms.

PubMed

Friedman-Krauss, Allison H; Raver, C Cybele; Neuspiel, Juliana M; Kinsel, John

2014-01-01

The current article explores the relationship between teachers' perceptions of child behavior problems and preschool teacher job stress, as well as the possibility that teachers' executive functions moderate this relationship. Data came from 69 preschool teachers in 31 early childhood classrooms in 4 Head Start centers and were collected using Web-based surveys and Web-based direct assessment tasks. Multilevel models revealed that higher levels of teachers' perceptions of child behavior problems were associated with higher levels of teacher job stress and that higher teacher executive function skills were related to lower job stress. However, findings did not yield evidence for teacher executive functions as a statistical moderator. Many early childhood teachers do not receive sufficient training for handling children's challenging behaviors. Child behavior problems increase a teacher's workload and consequently may contribute to feelings of stress. However, teachers' executive function abilities may enable them to use effective, cognitive-based behavior management and instructional strategies during interactions with students, which may reduce stress. Providing teachers with training on managing challenging behaviors and enhancing executive functions may reduce their stress and facilitate their use of effective classroom practices, which is important for children's school readiness skills and teachers' health.

Application of Optical Flow Sensors for Dead Reckoning, Heading Reference, Obstacle Detection, and Obstacle Avoidance

DTIC Science & Technology

2015-09-01

OPTICAL FLOW SENSORS FOR DEAD RECKONING, HEADING REFERENCE, OBSTACLE DETECTION, AND OBSTACLE AVOIDANCE by Tarek M. Nejah September 2015...SENSORS FOR DEAD RECKONING, HEADING REFERENCE, OBSTACLE DETECTION, AND OBSTACLE AVOIDANCE 5. FUNDING NUMBERS 6. AUTHOR(S) Nejah, Tarek M. 7...DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) A novel approach for dead reckoning, heading reference, obstacle detection, and obstacle

Visibility of Monocular Symbology in Transparent Head-Mounted Display Applications

DTIC Science & Technology

2015-07-08

Displays XX, edited by Daniel D. Desjardins, Peter L. Marasco , Kalluri R. Sarma, Paul R. Havig, Michael P. Browne, James E. Melzer, Proc. of SPIE Vol...simulators. in Head- and Helmet-Mounted Displays XV: Design and Applications, Proceedings of SPIE Volume 7688 (ed. Peter L. Marasco , P. R. H.) 7688, (2010

High School Coaches' Experiences With Openly Lesbian, Gay, and Bisexual Athletes.

PubMed

Halbrook, Meghan K; Watson, Jack C; Voelker, Dana K

2018-01-17

Despite reports that there has been a positive trend in perception and treatment of lesbian, gay, and bisexual (LGB) individuals in recent years (Griffin, 2012 ; Loftus, 2001 ), sport, in general, is still an uncertain, and sometimes even hostile, environment for LGB athletes (Anderson, 2005 ; Waldron & Krane, 2005 ). To gain more information on coach understanding and perceptions of the team environment, 10 high school head coaches in the United States were interviewed to explore their experiences coaching openly LGB athletes. Qualitative analyses revealed four primary themes associated with coach experiences: team environment dogmas and observations, fundamental beliefs contributing to perceptions of LGB athletes, types and timing of sexual orientation disclosure, and differential LGB athlete characteristics. Future research should examine these primary themes in more detail through interviews with LGB athletes, as well as high school coaches in more traditionally masculine sports, such as football, men's basketball, and wrestling.

Low intensity magnetic field influences short-term memory: A study in a group of healthy students.

PubMed

Navarro, Enrique A; Gomez-Perretta, Claudio; Montes, Francisco

2016-01-01

This study analyzes if an external magnetic stimulus (2 kHz and approximately 0.1 μT applied near frontal cortex) influences working memory, perception, binary decision, motor execution, and sustained attention in humans. A magnetic stimulus and a sham stimulus were applied to both sides of the head (frontal cortex close to temporal-parietal area) in young and healthy male test subjects (n = 65) while performing Sternberg's memory scanning task. There was a significant change in reaction time. Times recorded for perception, sustained attention, and motor execution were lower in exposed subjects (P < 0.01). However, time employed in binary decision increased for subjects exposed to magnetic fields. From results, it seems that a low intensity 2 kHz exposure modifies short-term working memory, as well as perception, binary decision, motor execution, and sustained attention. © 2015 Wiley Periodicals, Inc.

Gravitoinertial force magnitude and direction influence head-centric auditory localization

NASA Technical Reports Server (NTRS)

DiZio, P.; Held, R.; Lackner, J. R.; Shinn-Cunningham, B.; Durlach, N.

2001-01-01

We measured the influence of gravitoinertial force (GIF) magnitude and direction on head-centric auditory localization to determine whether a true audiogravic illusion exists. In experiment 1, supine subjects adjusted computer-generated dichotic stimuli until they heard a fused sound straight ahead in the midsagittal plane of the head under a variety of GIF conditions generated in a slow-rotation room. The dichotic stimuli were constructed by convolving broadband noise with head-related transfer function pairs that model the acoustic filtering at the listener's ears. These stimuli give rise to the perception of externally localized sounds. When the GIF was increased from 1 to 2 g and rotated 60 degrees rightward relative to the head and body, subjects on average set an acoustic stimulus 7.3 degrees right of their head's median plane to hear it as straight ahead. When the GIF was doubled and rotated 60 degrees leftward, subjects set the sound 6.8 degrees leftward of baseline values to hear it as centered. In experiment 2, increasing the GIF in the median plane of the supine body to 2 g did not influence auditory localization. In experiment 3, tilts up to 75 degrees of the supine body relative to the normal 1 g GIF led to small shifts, 1--2 degrees, of auditory setting toward the up ear to maintain a head-centered sound localization. These results show that head-centric auditory localization is affected by azimuthal rotation and increase in magnitude of the GIF and demonstrate that an audiogravic illusion exists. Sound localization is shifted in the direction opposite GIF rotation by an amount related to the magnitude of the GIF and its angular deviation relative to the median plane.

Motion versus position in the perception of head-centred movement.

PubMed

Freeman, Tom C A; Sumnall, Jane H

2002-01-01

Abstract. Observers can recover motion with respect to the head during an eye movement by comparing signals encoding retinal motion and the velocity of pursuit. Evidently there is a mismatch between these signals because perceived head-centred motion is not always veridical. One example is the Filehne illusion, in which a stationary object appears to move in the opposite direction to pursuit. Like the motion aftereffect, the phenomenal experience of the Filehne illusion is one in which the stimulus moves but does not seem to go anywhere. This raises problems when measuring the illusion by motion nulling because the more traditional technique confounds perceived motion with changes in perceived position. We devised a new nulling technique using global-motion stimuli that degraded familiar position cues but preserved cues to motion. Stimuli consisted of random-dot patterns comprising signal and noise dots that moved at the same retinal 'base' speed. Noise moved in random directions. In an eye-stationary speed-matching experiment we found noise slowed perceived retinal speed as 'coherence strength' (ie percentage of signal) was reduced. The effect occurred over the two-octave range of base speeds studied and well above direction threshold. When the same stimuli were combined with pursuit, observers were able to null the Filehne illusion by adjusting coherence. A power law relating coherence to retinal base speed fit the data well with a negative exponent. Eye-movement recordings showed that pursuit was quite accurate. We then tested the hypothesis that the stimuli found at the null-points appeared to move at the same retinal speed. Two observers supported the hypothesis, a third partially, and a fourth showed a small linear trend. In addition, the retinal speed found by the traditional Filehne technique was similar to the matches obtained with the global-motion stimuli. The results provide support for the idea that speed is the critical cue in head-centred motion perception.

Industrial and biomedical use of aerospace personal cooling garments

NASA Technical Reports Server (NTRS)

Williams, B. A.; Mcewen, G. N., Jr.; Montgomery, L. D.; Elkins, W. E.

1975-01-01

Liquid-cooled garments (LCG) have been developed which utilize liquid-cooled modules rather than the network of tygon tubing typical of Apollo LCG's. The ultra-thin, heat-sealed, polyurethane modules are situated over the body to cover 50 percent of the body surface area with special emphasis on the 'working' muscles and the head-neck area. These garments are being designed specifically for industrial and biomedical uses, such as: a head-neck cooling system which is being tested for race-car drivers, tractor drivers, truck drivers, or a head-neck cooling system tested for the reduction of the scalp hair loss which normally accompanies cancer treatments. A combined head-neck and thorax unit is being developed for use during mine distaster rescue operations, and for other hazardous hot applications. Finally applications for head-neck and partitional cooling are anticipated for military pilots, tank drivers, and heavy equipment operations.

Theory and application of a three-dimensional model of the human spine.

PubMed

Belytschko, T; Schwer, L; Privitzer, E

1978-01-01

A three-dimensional, discrete model of the human spine, torso, and head was developed for the purpose of evaluating mechanical response in pilot ejection. However, it was developed in sufficient generality to be applicable to other body response problems, such as occupant response in aircraft crash and arbitrary loads on the head-spine system. The anatomy is modelled by a collection of rigid bodies, which represent skeletal segments such as the vertebrae, pelvis, head, and ribs, interconnected by deformable elements, which represent ligaments, cargilagenous joints, viscera and connective tissues. Results are presented for several conditions: different rates of onset, ejection at angles, preejection alignment, and eccentric head loadings. It is shown that slow rates of onset and angling the seat reduce both the peak axial loads and bending moments. In the presence of eccentric head masses, such as helmet-mounted devices, the reflected flexural wave is shown to be the key injury mechanism.

Multisensory Integration of Visual and Vestibular Signals Improves Heading Discrimination in the Presence of a Moving Object

PubMed Central

Dokka, Kalpana; DeAngelis, Gregory C.

2015-01-01

Humans and animals are fairly accurate in judging their direction of self-motion (i.e., heading) from optic flow when moving through a stationary environment. However, an object moving independently in the world alters the optic flow field and may bias heading perception if the visual system cannot dissociate object motion from self-motion. We investigated whether adding vestibular self-motion signals to optic flow enhances the accuracy of heading judgments in the presence of a moving object. Macaque monkeys were trained to report their heading (leftward or rightward relative to straight-forward) when self-motion was specified by vestibular, visual, or combined visual-vestibular signals, while viewing a display in which an object moved independently in the (virtual) world. The moving object induced significant biases in perceived heading when self-motion was signaled by either visual or vestibular cues alone. However, this bias was greatly reduced when visual and vestibular cues together signaled self-motion. In addition, multisensory heading discrimination thresholds measured in the presence of a moving object were largely consistent with the predictions of an optimal cue integration strategy. These findings demonstrate that multisensory cues facilitate the perceptual dissociation of self-motion and object motion, consistent with computational work that suggests that an appropriate decoding of multisensory visual-vestibular neurons can estimate heading while discounting the effects of object motion. SIGNIFICANCE STATEMENT Objects that move independently in the world alter the optic flow field and can induce errors in perceiving the direction of self-motion (heading). We show that adding vestibular (inertial) self-motion signals to optic flow almost completely eliminates the errors in perceived heading induced by an independently moving object. Furthermore, this increased accuracy occurs without a substantial loss in the precision. Our results thus demonstrate that vestibular signals play a critical role in dissociating self-motion from object motion. PMID:26446214

SU-E-T-352: Effects of Skull Attenuation and Missing Backscatter On Brain Dose in HDR Treatment of the Head with Surface Applicators

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

Cifter, F; Dhou, S; Lewis, J

2015-06-15

Purpose: To calculate the effect of lack of backscatter from air and attenuation of bone on dose distributions in brachytherapy surface treatment of head. Existing treatment planning systems based on TG43 do not account for heterogeneities, and thus may overestimate the dose to the brain. While brachytherapy generally has rapid dose falloff, the dose to the deeper tissues (in this case, the brain) can become significant when treating large curved surfaces. Methods: Applicator geometries representing a range of clinical cases were simulated in MCNP5. An Ir-192 source was modeled using the energy spectrum presented by TG-43. The head phantom wasmore » modeled as a 7.5-cm radius water sphere, with a 7 -mm thick skull embedded 5-mm beneath the surface. Dose values were calculated at 20 points inside the head, in which 10 of them were on the central axis and the other 10 on the axis connecting the central of the phantom with the second to last source from the applicator edge. Results: Central and peripheral dose distributions for a range of applicator and head sizes are presented. The distance along the central axis at which the dose falls to 80% of the prescribed dose (D80) was 7 mm for a representative small applicator and 9 mm for a large applicator. Corresponding D50 and D30 for the same small applicator were 17 mm and 32 mm respectively. D50 and D30 for the larger applicator were 32 mm and 60 mm respectively. These results reflect the slower falloff expected for larger applicators on a curved surface. Conclusion: Our results can provide guidance for clinicians to calculate the dose reduction effect due to bone attenuation and the lack of backscatter from air to estimate the brain dose for the HDR treatments of surface lesions.« less

Heads-up 3D Microscopy: An Ergonomic and Educational Approach to Microsurgery

PubMed Central

Mendez, Bernardino M.; Chiodo, Michael V.; Vandevender, Darl

2016-01-01

Summary: Traditional microsurgery can lead surgeons to use postures that cause musculoskeletal fatigue, leaving them more prone to work-related injuries. A new technology from TrueVision transmits the microscopic image onto a 3-dimensional (3D) monitor, allowing surgeons to operate while sitting/standing in a heads-up position. The purpose of this study was to evaluate the feasibility of performing heads-up 3D microscopy as a more ergonomic alternative to traditional microsurgery. A feasibility study was conducted comparing heads-up 3D microscopy and traditional microscopy by performing femoral artery anastomoses on 8 Sprague-Dawley rats. Operative times and patency rates for each technology were compared. The 8 microsurgeons completed a questionnaire comparing image quality, comfort, technical feasibility, and educational value of the 2 technologies. Rat femoral artery anastomoses were successfully carried out by all 8 microsurgeons with each technology. There was no significant difference in anastomosis time between heads-up 3D and traditional microscopy (average times, 34.5 and 33.8 minutes, respectively; P = 0.66). Heads-up 3D microscopy was rated superior in neck and back comfort by 75% of participants. Image resolution, field of view, and technical feasibility were found to be superior or equivalent in 75% of participants, whereas 63% evaluated depth perception to be superior or equivalent. Heads-up 3D microscopy is a new technology that improves comfort for the microsurgeon without compromising image quality or technical feasibility. Its use has become prevalent in the field of ophthalmology and may also have utility in plastic and reconstructive surgery. PMID:27579241

Clinical application of a modern high-definition head-mounted display in sonography.

PubMed

Takeshita, Hideki; Kihara, Kazunori; Yoshida, Soichiro; Higuchi, Saori; Ito, Masaya; Nakanishi, Yasukazu; Kijima, Toshiki; Ishioka, Junichiro; Matsuoka, Yoh; Numao, Noboru; Saito, Kazutaka; Fujii, Yasuhisa

2014-08-01

Because of the remarkably improved image quality and wearability of modern head-mounted displays, a monitoring system using a head-mounted display rather than a fixed-site monitor for sonographic scanning has the potential to improve the diagnostic performance and lessen the examiner's physical burden during a sonographic examination. In a preclinical setting, 2 head-mounted displays, the HMZ-T2 (Sony Corporation, Tokyo, Japan) and the Wrap1200 (Vuzix Corporation, Rochester, NY), were found to be applicable to sonography. In a clinical setting, the feasibility of the HMZ-T2 was shown by its good image quality and acceptable wearability. This modern device is appropriate for clinical use in sonography. © 2014 by the American Institute of Ultrasound in Medicine.

Virtual reality in rhinology-a new dimension of clinical experience.

PubMed

Klapan, Ivica; Raos, Pero; Galeta, Tomislav; Kubat, Goranka

2016-07-01

There is often a need to more precisely identify the extent of pathology and the fine elements of intracranial anatomic features during the diagnostic process and during many operations in the nose, sinus, orbit, and skull base region. In two case reports, we describe the methods used in the diagnostic workup and surgical therapy in the nose and paranasal sinus region. Besides baseline x-ray, multislice computed tomography, and magnetic resonance imaging, operative field imaging was performed via a rapid prototyping model, virtual endoscopy, and 3-D imaging. Different head tissues were visualized in different colors, showing their anatomic interrelations and the extent of pathologic tissue within the operative field. This approach has not yet been used as a standard preoperative or intraoperative procedure in otorhinolaryngology. In this way, we tried to understand the new, visualized "world of anatomic relations within the patient's head" by creating an impression of perception (virtual perception) of the given position of all elements in a particular anatomic region of the head, which does not exist in the real world (virtual world). This approach was aimed at upgrading the diagnostic workup and surgical therapy by ensuring a faster, safer and, above all, simpler operative procedure. In conclusion, any ENT specialist can provide virtual reality support in implementing surgical procedures, with additional control of risks and within the limits of normal tissue, without additional trauma to the surrounding tissue in the anatomic region. At the same time, the virtual reality support provides an impression of the virtual world as the specialist navigates through it and manipulates virtual objects.

Conservation of water for washing beef heads at harvest

USDA-ARS?s Scientific Manuscript database

The objective of this research was to develop methods to conserve water necessary to cleanse beef heads prior to USDA–FSIS inspection. This was to be accomplished by establishing a baseline for the minimum amount of water necessary to adequately wash a head and application of image analysis to provi...

Range-Gated Metrology with Compact Optical Head

NASA Technical Reports Server (NTRS)

Dubovitsky, Serge; Shaddock, Daniel; Ware, Brent; Lay, Oliver

2008-01-01

This work represents a radical simplification in the design of the optical head needed for high-precision laser ranging applications. The optical head is now a single fiber-optic collimator with dimensions of order of 1 1 2 cm, which can be easily integrated into the system being measured with minimal footprint.

45 CFR 1305.3 - Determining community strengths and needs.

Code of Federal Regulations, 2013 CFR

2013-10-01

... grantee must identify its proposed service area in its Head Start grant application and define it by... regarding the education, health, nutrition and social service needs of Head Start eligible children and their families; (5) The education, health, nutrition and social service needs of Head Start eligible...

45 CFR 1305.3 - Determining community strengths and needs.

Code of Federal Regulations, 2010 CFR

2010-10-01

... grantee must identify its proposed service area in its Head Start grant application and define it by... regarding the education, health, nutrition and social service needs of Head Start eligible children and their families; (5) The education, health, nutrition and social service needs of Head Start eligible...

45 CFR 1305.3 - Determining community strengths and needs.

Code of Federal Regulations, 2012 CFR

2012-10-01

... grantee must identify its proposed service area in its Head Start grant application and define it by... regarding the education, health, nutrition and social service needs of Head Start eligible children and their families; (5) The education, health, nutrition and social service needs of Head Start eligible...

45 CFR 1305.3 - Determining community strengths and needs.

Code of Federal Regulations, 2011 CFR

2011-10-01

... grantee must identify its proposed service area in its Head Start grant application and define it by... regarding the education, health, nutrition and social service needs of Head Start eligible children and their families; (5) The education, health, nutrition and social service needs of Head Start eligible...

45 CFR 1305.3 - Determining community strengths and needs.

Code of Federal Regulations, 2014 CFR

2014-10-01

... grantee must identify its proposed service area in its Head Start grant application and define it by... regarding the education, health, nutrition and social service needs of Head Start eligible children and their families; (5) The education, health, nutrition and social service needs of Head Start eligible...

Head office commitment to quality-related event reporting in community pharmacy

PubMed Central

Scobie, Andrea C.; Boyle, Todd A.; MacKinnon, Neil J.; Mahaffey, Thomas

2012-01-01

Background: This research explores how perceptions of head office commitment to quality-related event (QRE) reporting differ between pharmacy staff type and between pharmacies with high and low QRE reporting and learning performance. QREs include known, alleged or suspected medication errors that reach the patient as well as medication errors that are intercepted prior to dispensing. Methods: A survey questionnaire was mailed in the spring of 2010 to 427 pharmacy managers, pharmacists and pharmacy technicians in Nova Scotia. Nonparametric statistics were used to determine differences based on pharmacy staff type and pharmacy performance. Content analysis was used to analyze the responses to open-ended survey questions. Results: A total of 210 surveys were returned, for a response rate of 49.2%. However, the current study used only the subgroup of pharmacy staff who self-reported working at a chain pharmacy, for a total of 124 usable questionnaires. The results showed that community pharmacies viewed head office commitment to QRE reporting as an area to improve. In general, high-performing pharmacies ranked head office commitment higher than low-performing pharmacies. Discussion: One possible reason why high-performing pharmacies ranked the variables higher may be that increased levels of head office support for QRE processes have led these pharmacies to adopt and commit to QRE processes and thus increase their performance. Conclusion: Demonstrated commitment to QRE reporting, ongoing encouragement and targeted messages to staff could be important steps for head office to increase QRE reporting and learning in community pharmacies. PMID:23509532

Head office commitment to quality-related event reporting in community pharmacy.

PubMed

Scobie, Andrea C; Boyle, Todd A; Mackinnon, Neil J; Mahaffey, Thomas

2012-05-01

This research explores how perceptions of head office commitment to quality-related event (QRE) reporting differ between pharmacy staff type and between pharmacies with high and low QRE reporting and learning performance. QREs include known, alleged or suspected medication errors that reach the patient as well as medication errors that are intercepted prior to dispensing. A survey questionnaire was mailed in the spring of 2010 to 427 pharmacy managers, pharmacists and pharmacy technicians in Nova Scotia. Nonparametric statistics were used to determine differences based on pharmacy staff type and pharmacy performance. Content analysis was used to analyze the responses to open-ended survey questions. A total of 210 surveys were returned, for a response rate of 49.2%. However, the current study used only the subgroup of pharmacy staff who self-reported working at a chain pharmacy, for a total of 124 usable questionnaires. The results showed that community pharmacies viewed head office commitment to QRE reporting as an area to improve. In general, high-performing pharmacies ranked head office commitment higher than low-performing pharmacies. One possible reason why high-performing pharmacies ranked the variables higher may be that increased levels of head office support for QRE processes have led these pharmacies to adopt and commit to QRE processes and thus increase their performance. Demonstrated commitment to QRE reporting, ongoing encouragement and targeted messages to staff could be important steps for head office to increase QRE reporting and learning in community pharmacies.

Furthering the understanding of olfaction, prevalence of loss of smell and risk factors: a population-based survey (OLFACAT study)

PubMed Central

Mullol, Joaquim; Alobid, Isam; Mariño-Sánchez, Franklin; Quintó, Llorenç; de Haro, Josep; Bernal-Sprekelsen, Manuel; Valero, Antonio; Picado, Cèsar; Marin, Concepció

2012-01-01

Objectives To investigate olfaction in general population, prevalence of olfactory dysfunction and related risk factors. Design Cross-sectional population-based survey, distributing four microencapsulated odorants (rose, banana, musk and gas) and two self-administered questionnaires (odour description; epidemiology/health status). Setting The survey was distributed to general population through a bilingual (Catalan, Spanish) newspaper in Catalonia (Spain), on December 2003. Participants Newspaper readers of all ages and gender; 9348 surveys were analysed from the 10 783 returned. Main outcome measures Characteristics of surveyed population, olfaction by age and gender, smell self-perception and smell impairment risk factors. Terms normosmia, hyposmia and anosmia were used when participants detected, recognised or identified all four, one to three or none of the odours, respectively. Results Survey profile was a 43-year-old woman with medium–high educational level, living in a city. Olfaction was considered normal in 80.6% (detection), 56% (recognition/memory) and 50.7% (identification). Prevalence of smell dysfunction was 19.4% for detection (0.3% anosmia, 19.1% hyposmia), 43.5% for recognition (0.2% anosmia, 43.3% hyposmia) and 48.8% for identification (0.8% anosmia, 48% hyposmia). Olfaction was worse (p<0.0001) in men than in women through all ages. There was a significant age-related smell detection decline however smell recognition and identification increased up to fourth decade and declined after the sixth decade of life. Risk factors for anosmia were: male gender, loss of smell history and poor olfactory self-perception for detection; low educational level, poor self-perception and pregnancy for recognition; and older age, poor self-perception and history of head trauma and loss of smell for identification. Smoking and exposure to noxious substances were mild protective factors for smell recognition. Conclusions Sense of smell in women is better than in men suggesting a learning process during life with deterioration in older ages. Poor self-perception, history of smell loss, head trauma and pregnancy are potential risk factors for olfactory disorders. PMID:23135536

[Duodenum-preserving total pancreatic head resection and pancreatic head resection with segmental duodenostomy].

PubMed

Takada, Tadahiro; Yasuda, Hideki; Nagashima, Ikuo; Amano, Hodaka; Yoshiada, Masahiro; Toyota, Naoyuki

2003-06-01

A duodenum-preserving pancreatic head resection (DPPHR) was first reported by Beger et al. in 1980. However, its application has been limited to chronic pancreatitis because of it is a subtotal pancreatic head resection. In 1990, we reported duodenum-preserving total pancreatic head resection (DPTPHR) in 26 cases. This opened the way for total pancreatic head resection, expanding the application of this approach to tumorigenic morbidities such as intraductal papillary mucinous tumor (IMPT), other benign tumors, and small pancreatic cancers. On the other hand, Nakao et al. reported pancreatic head resection with segmental duodenectomy (PHRSD) as an alternative pylorus-preserving pancreatoduodenectomy technique in 24 cases. Hirata et al. also reported this technique as a new pylorus-preserving pancreatoduodenostomy with increased vessel preservation. When performing DPTPHR, the surgeon should ensure adequate duodenal blood supply. Avoidance of duodenal ischemia is very important in this operation, and thus it is necessary to maintain blood flow in the posterior pancreatoduodenal artery and to preserve the mesoduodenal vessels. Postoperative pancreatic functional tests reveal that DPTPHR is superior to PPPD, including PHSRD, because the entire duodenum and duodenal integrity is very important for postoperative pancreatic function.

Medical School Experiences Shape Women Students' Interest in Orthopaedic Surgery.

PubMed

O'Connor, Mary I

2016-09-01

Orthopaedic surgery now has the lowest percentage of women in residency programs of any surgical specialty. Understanding factors, particularly those related to the medical school experience, that contribute to the specialty's inability to draw from the best women students is crucial to improving diversity in the profession. (1) Does required medical school exposure to orthopaedic surgery increase the proportion of women choosing the specialty? (2) Do negative perceptions deter women from choosing orthopaedic surgery? (3) What proportion of orthopaedic faculty members are women, and what proportion of residents are women? (4) To what degree has gender bias been identified in the application/interview process? Two PubMed searches of articles between 2005 and 2015 were performed using a combination of medical subject headings. The first search combined "Orthopaedics" with "Physicians, women" and phrases "women surgeons" or "female surgeons" and the second combined "Orthopedics" with "Internship & Residency" or "exp Education, Medical" and "Sex Ratio" or "Sex Factors", resulting in 46 publications of which all abstracts were reviewed resulting in 11 manuscripts that were related to the research questions. The Google Scholar search of "women in orthopaedic surgery" identified one additional publication. These 12 manuscripts were read and bibliographies of each reviewed with two additional publications identified and included. Required exposure to orthopaedics was found to be positively associated with the number of women applicants to the field, whereas negative perceptions have been reported to deter women from choosing orthopaedic surgery. Orthopaedics has the lowest percentage of women faculty and women residents (14%) compared with other specialties; this suggests that same gender mentorship opportunities are limited. For women applying to orthopaedics, gender bias is most evident through illegal interview questions, in which women are asked such questions more often than men (such as family planning questions, asked to 61% of women versus 8% of men). Successful recruitment of women to orthopaedic surgery may be improved by early exposure and access to role models, both of which will help women students' perceptions of their role in field of orthopaedic surgery.

Visual cueing considerations in Nap-of-the-Earth helicopter flight head-slaved helmet-mounted displays

NASA Technical Reports Server (NTRS)

Grunwald, Arthur J.; Kohn, Silvia

1993-01-01

The pilot's ability to derive Control-Oriented Visual Field Information from teleoperated Helmet-Mounted displays in Nap-of-the-Earth flight, is investigated. The visual field with these types of displays, commonly used in Apache and Cobra helicopter night operations, originates from a relatively narrow field-of-view Forward Looking Infrared Radiation Camera, gimbal-mounted at the nose of the aircraft and slaved to the pilot's line-of-sight, in order to obtain a wide-angle field-of-regard. Pilots have encountered considerable difficulties in controlling the aircraft by these devices. Experimental simulator results presented here indicate that part of these difficulties can be attributed to head/camera slaving system phase lags and errors. In the presence of voluntary head rotation, these slaving system imperfections are shown to impair the Control-Oriented Visual Field Information vital in vehicular control, such as the perception of the anticipated flight path or the vehicle yaw rate. Since, in the presence of slaving system imperfections, the pilot will tend to minimize head rotation, the full wide-angle field-of-regard of the line-of-sight slaved Helmet-Mounted Display, is not always fully utilized.

Spatiotemporal mapping of scalp potentials.

PubMed

Fender, D H; Santoro, T P

1977-11-01

Computerized analysis and display techniques are applied to the problem of identifying the origins of visually evoked scalped potentials (VESP's). A new stimulus for VESP work, white noise, is being incorporated in the solution of this problem. VESP's for white-noise stimulation exhibit time domain behavior similar to the classical response for flash stimuli but with certain significant differences. Contour mapping algorithms are used to display the time behavior of equipotential surfaces on the scalp during the VESP. The electrical and geometrical parameters of the head are modeled. Electrical fields closely matching those obtained experimentally are generated on the surface of the model head by optimally selecting the location and strength parameters of one or two dipole current sources contained within the model. Computer graphics are used to display as a movie the actual and model scalp potential field and the parameters of the dipole generators whithin the model head during the time course of the VESP. These techniques are currently used to study retinotopic mapping, fusion, and texture perception in the human.

Using Student-Produced Video to Validate Head-to-Toe Assessment Performance.

PubMed

Purpora, Christina; Prion, Susan

2018-03-01

This study explored third-semester baccalaureate nursing students' perceptions of the value of using student-produced video as an approach for learning head-to-toe assessment, an essential clinical nursing skill taught in the classroom. A cognitive apprenticeship model guided the study. The researchers developed a 34-item survey. A convenience sample of 72 students enrolled in an applied assessment and nursing fundamentals course at a university in the western United States provided the data. Most students reported a videotaping process that worked, supportive faculty, valuable faculty review of their work, confidence, a sense of performance independence, the ability to identify normal assessment findings, and few barriers to learning. The results suggested that a student-produced video approach to learning head-to-toe assessment was effective. Further, the study demonstrated how to leverage available instructional technology to provide meaningful, personalized instruction and feedback to students about an essential nursing skill. [J Nurs Educ. 2018;57(3):154-158.]. Copyright 2018, SLACK Incorporated.

Patients' Body Image Improves After Mohs Micrographic Surgery for Nonmelanoma Head and Neck Skin Cancer.

PubMed

Beal, Brandon T; White, Emily K; Behera, Anit K; Zavell, Amy E; McGuinness, Ashley E; Blangger, Holly; Armbrecht, Eric S; Maher, Ian A

2018-05-24

Most skin cancers occur on the head and neck, areas of the body that are significant to an individual's body image (BI) perception. Poor BI is a robust risk factor for depression and decreased quality of life. Thus, patients with nonmelanoma head and neck skin cancer (NMHNSC) may be more vulnerable to BI disturbance and the negative sequelae of poor BI. Describe the nature of BI concerns in patients diagnosed with NMHNSC and assess how BI changes with treatment. Patients undergoing Mohs micrographic surgery (MMS) for NMHNSC completed assessments of BI and well-being before (N = 239) and 6 months after (N = 80) treatment with MMS. Demographic and tumor data were gathered through retrospective chart review. Body image improved significantly 6 months after MMS, and the magnitude of this change was large (η = 0.18). Repair length (length of final scar irrespective of repair type) >4 cm predicted poorer BI at 6-month follow-up. Patients' BI improves after treatment with MMS for NMHNSC.

Visual perception and social foraging in birds.

PubMed

Fernández-Juricic, Esteban; Erichsen, Jonathan T; Kacelnik, Alex

2004-01-01

Birds gather information about their environment mainly through vision by scanning their surroundings. Many prevalent models of social foraging assume that foraging and scanning are mutually exclusive. Although this assumption is valid for birds with narrow visual fields, these models have also been applied to species with wide fields. In fact, available models do not make precise predictions for birds with large visual fields, in which the head-up, head-down dichotomy is not accurate and, moreover, do not consider the effects of detection distance and limited attention. Studies of how different types of visual information are acquired as a function of body posture and of how information flows within flocks offer new insights into the costs and benefits of living in groups.

Sensorimotor strategies for recognizing geometrical shapes: a comparative study with different sensory substitution devices

PubMed Central

Bermejo, Fernando; Di Paolo, Ezequiel A.; Hüg, Mercedes X.; Arias, Claudia

2015-01-01

The sensorimotor approach proposes that perception is constituted by the mastery of lawful sensorimotor regularities or sensorimotor contingencies (SMCs), which depend on specific bodily characteristics and on actions possibilities that the environment enables and constrains. Sensory substitution devices (SSDs) provide the user information about the world typically corresponding to one sensory modality through the stimulation of another modality. We investigate how perception emerges in novice adult participants equipped with vision-to-auditory SSDs while solving a simple geometrical shape recognition task. In particular, we examine the distinction between apparatus-related SMCs (those originating mostly in properties of the perceptual system) and object-related SMCs (those mostly connected with the perceptual task). We study the sensorimotor strategies employed by participants in three experiments with three different SSDs: a minimalist head-mounted SSD, a traditional, also head-mounted SSD (the vOICe) and an enhanced, hand-held echolocation device. Motor activity and fist-person data are registered and analyzed. Results show that participants are able to quickly learn the necessary skills to distinguish geometric shapes. Comparing the sensorimotor strategies utilized with each SSD we identify differential features of the sensorimotor patterns attributable mostly to the device, which account for the emergence of apparatus-based SMCs. These relate to differences in sweeping strategies between SSDs. We identify, also, components related to the emergence of object-related SMCs. These relate mostly to exploratory movements around the border of a shape. The study provides empirical support for SMC theory and discusses considerations about the nature of perception in sensory substitution. PMID:26106340

50 Tactile and Visual Perception Games for Under $10: A Guide to Reading Readiness Games for Pre-School Teachers, Head Start Teachers, and First Grade Teachers.

ERIC Educational Resources Information Center

Cangemi, Sam

This guide describes and illustrates 50 perceptual games for preschool children which may be constructed by teachers. Inexpensive, easily obtained game materials are suggested. The use of tactile and visual perceptual games gives children opportunities to make choices and discriminations, and provides reading readiness experiences. Games depicted…

Embodied Spatial Transformations: "Body Analogy" for the Mental Rotation of Objects

ERIC Educational Resources Information Center

Amorim, Michel-Ange; Isableu, Brice; Jarraya, Mohamed

2006-01-01

The cognitive advantage of imagined spatial transformations of the human body over that of more unfamiliar objects (e.g., Shepard-Metzler [S-M] cubes) is an issue for validating motor theories of visual perception. In 6 experiments, the authors show that providing S-M cubes with body characteristics (e.g., by adding a head to S-M cubes to evoke a…

Military Nurses Perceptions of Autonomy

DTIC Science & Technology

2002-05-01

Medical Battalion, Fort Sam Houston, TX. 1996-1998 Head Nurse, Newborn Nursery, Bayne -Jones Army Community Hospital, Fort Polk, LA. 1996-1998 Staff Nurse...Army Medical Center, Fort Sam Houston, TX. 1984-1990 NCOIC, Department of Biochemistry , Division of Biochemistry , Walter Reed Army Institute of...Publications:(under previous name De La Hoz)(Selected) De La Hoz, D. and Wood, S. (1995). Pediatric Quick Reference. Brooke Army Medical Center, Fort Sam

Why Three Heads Are a Better Bet than Four: A Reply to Sun, Tweney, and Wang (2010)

ERIC Educational Resources Information Center

Hahn, Ulrike; Warren, Paul A.

2010-01-01

We (Hahn & Warren, 2009) recently proposed a new account of the systematic errors and biases that appear to be present in people's perception of randomly generated events. In a comment on that article, Sun, Tweney, and Wang (2010) critiqued our treatment of the gambler's fallacy. We had argued that this fallacy was less gross an error than it…

The Role of Parent Governors in School Governance in Zimbabwe: Perceptions of School Heads, Teachers and Parent Governors

ERIC Educational Resources Information Center

Chikoko, Vitallis

2008-01-01

This paper reports on a study of the role of parent governors in five neighbouring rural primary schools in Zimbabwe. The study proposed that despite the presence of a legal decentralised school governance structure in which parents form the majority, they did not have the capacity to function effectively therein, and were still marginalised in…

Liposomal treatment of xerostomia, odor, and taste abnormalities in patients with head and neck cancer.

PubMed

Heiser, Clemens; Hofauer, Benedikt; Scherer, Elias; Schukraft, Johannes; Knopf, Andreas

2016-04-01

Smell and taste disorders, sicca symptoms, can be detected in patients with head and neck cancer. The purpose of this study was to assess the utility of local liposomal application in the treatment of patients with head and neck cancers. Ninety-eight patients with head and neck cancer were included in this study. The groups were defined as: group 1 = only surgery; group 2 = surgery + adjuvant radiochemotherapy; and group 3 = primarily radiochemotherapy. All patients had finished cancer treatment and received liposomal sprays for the nose and mouth for 2 months (LipoNasal, LipoSaliva; Optima Pharmaceutical GmbH, Germany) and suffered from taste and smell disorders. We performed tests with "Sniffin' Sticks," "Taste Strips," and a xerostomia questionnaire before and after treatment. After application of liposomes, patients demonstrated a statistically significant increase in smell and taste, and reduced xerostomia. Our results demonstrate that using nonpharmaceutical liposomal sprays improve smell, taste, and symptoms of xerostomia in patients with head and neck cancer. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1232-E1237, 2016. © 2015 Wiley Periodicals, Inc.

Students' Perceptions of Teaching Technologies, Application of Technologies, and Academic Performance

ERIC Educational Resources Information Center

Tang, Thomas Li-Ping; Austin, M. Jill

2009-01-01

This study examined business students' perceptions of four objectives (i.e., Enjoyment, Learning, Motivation, and Career Application) across five teaching technologies (i.e., Projector, PowerPoint, Video, the Internet, and Lecture), business professors' effective application of technologies, and students' academic performance. We collected data…

Head stabilisation in fast running lizards.

PubMed

Goyens, Jana; Aerts, Peter

2018-04-01

The cyclic patterns of terrestrial animal locomotion are frequently perturbed in natural environments. The terrain can be complex or inclined, the substrate can move unexpectedly and animals can misjudge situations. Loosing stability due to perturbations increases the probability of capture by predators and decreases the chance of successful prey capture and winning intraspecific battles. When controlled corrective actions are necessary to negotiate perturbations, animals rely on their exteroceptive and proprioceptive senses to monitor the environment and their own body movements. The vestibular system in the inner ear perceives linear and angular accelerations. This information enables gaze stabilisation and the creation of a stable, world-bound reference frame for the integration of the information of other senses. During locomotion, both functions are known to be facilitated by head stabilisation in several animals with an erect posture. Animals with a sprawled body posture, however, undergo very large body undulations while running. Using high speed video recordings, we tested whether they nevertheless stabilise their head during running, and how this is influenced by perturbations. We found that running Acanthodactylus boskianus lizards strongly stabilise their head yaw rotations when running on a flat, straight runway: the head rotation amplitude is only 4.76±0.99°, while the adjacent trunk part rotates over 27.0±3.8°. Lateral head translations are not stabilised (average amplitude of 7.4±2.0mm). When the lizards are experimentally perturbed by a large and unexpected lateral substrate movement, lateral translations of both the head and the body decrease (on average by 1.52±0.81mm). At the same time, the rotations of the head and trunk also decrease (on average by 1.62°±7.21°). These results show that head stabilisation intensifies because of the perturbation, which emphasises the importance of vestibular perception and balance in these fast and manoeuvrable animals. Copyright © 2017 Elsevier GmbH. All rights reserved.

The Contribution of Head Movement to the Externalization and Internalization of Sounds

PubMed Central

Brimijoin, W. Owen; Boyd, Alan W.; Akeroyd, Michael A.

2013-01-01

Background When stimuli are presented over headphones, they are typically perceived as internalized; i.e., they appear to emanate from inside the head. Sounds presented in the free-field tend to be externalized, i.e., perceived to be emanating from a source in the world. This phenomenon is frequently attributed to reverberation and to the spectral characteristics of the sounds: those sounds whose spectrum and reverberation matches that of free-field signals arriving at the ear canal tend to be more frequently externalized. Another factor, however, is that the virtual location of signals presented over headphones moves in perfect concert with any movements of the head, whereas the location of free-field signals moves in opposition to head movements. The effects of head movement have not been systematically disentangled from reverberation and/or spectral cues, so we measured the degree to which movements contribute to externalization. Methodology/Principal Findings We performed two experiments: 1) Using motion tracking and free-field loudspeaker presentation, we presented signals that moved in their spatial location to match listeners’ head movements. 2) Using motion tracking and binaural room impulse responses, we presented filtered signals over headphones that appeared to remain static relative to the world. The results from experiment 1 showed that free-field signals from the front that move with the head are less likely to be externalized (23%) than those that remain fixed (63%). Experiment 2 showed that virtual signals whose position was fixed relative to the world are more likely to be externalized (65%) than those fixed relative to the head (20%), regardless of the fidelity of the individual impulse responses. Conclusions/Significance Head movements play a significant role in the externalization of sound sources. These findings imply tight integration between binaural cues and self motion cues and underscore the importance of self motion for spatial auditory perception. PMID:24312677

Fibre optic strain sensor: examples of applications

NASA Astrophysics Data System (ADS)

Kruszewski, J.; Beblowska, M.; Wrzosek, P.

2006-03-01

Construction of strain sensor for application in safety systems has been presented. The device consists of sensor's head and source and detector units. The head is made of polymer fiber bends. Designed sensor could be mounted in monitoring place (e.g. under a floor) and controlled by PC unit or could be used as a portable device for a valuable object protection.

Visual-Motor Transformations Within Frontal Eye Fields During Head-Unrestrained Gaze Shifts in the Monkey.

PubMed

Sajad, Amirsaman; Sadeh, Morteza; Keith, Gerald P; Yan, Xiaogang; Wang, Hongying; Crawford, John Douglas

2015-10-01

A fundamental question in sensorimotor control concerns the transformation of spatial signals from the retina into eye and head motor commands required for accurate gaze shifts. Here, we investigated these transformations by identifying the spatial codes embedded in visually evoked and movement-related responses in the frontal eye fields (FEFs) during head-unrestrained gaze shifts. Monkeys made delayed gaze shifts to the remembered location of briefly presented visual stimuli, with delay serving to dissociate visual and movement responses. A statistical analysis of nonparametric model fits to response field data from 57 neurons (38 with visual and 49 with movement activities) eliminated most effector-specific, head-fixed, and space-fixed models, but confirmed the dominance of eye-centered codes observed in head-restrained studies. More importantly, the visual response encoded target location, whereas the movement response mainly encoded the final position of the imminent gaze shift (including gaze errors). This spatiotemporal distinction between target and gaze coding was present not only at the population level, but even at the single-cell level. We propose that an imperfect visual-motor transformation occurs during the brief memory interval between perception and action, and further transformations from the FEF's eye-centered gaze motor code to effector-specific codes in motor frames occur downstream in the subcortical areas. © The Author 2014. Published by Oxford University Press.

The effects of social pressure and emotional expression on the cone of gaze in patients with social anxiety disorder.

PubMed

Harbort, Johannes; Spiegel, Julia; Witthöft, Michael; Hecht, Heiko

2017-06-01

Patients with social anxiety disorder suffer from pronounced fears in social situations. As gaze perception is crucial in these situations, we examined which factors influence the range of gaze directions where mutual gaze is experienced (the cone of gaze). The social stimulus was modified by changing the number of people (heads) present and the emotional expression of their faces. Participants completed a psychophysical task, in which they had to adjust the eyes of a virtual head to gaze at the edge of the range where mutual eye-contact was experienced. The number of heads affected the width of the gaze cone: the more heads, the wider the gaze cone. The emotional expression of the virtual head had no consistent effect on the width of the gaze cone, it did however affect the emotional state of the participants. Angry expressions produced the highest arousal values. Highest valence emerged from happy faces, lowest valence from angry faces. These results suggest that the widening of the gaze cone in social anxiety disorder is not primarily mediated by their altered emotional reactivity. Implications for gaze assessment and gaze training in therapeutic contexts are discussed. Due to interindividual variability, enlarged gaze cones are not necessarily indicative of social anxiety disorder, they merely constitute a correlate at the group level. Copyright © 2016 Elsevier Ltd. All rights reserved.

A priori mesh grading for the numerical calculation of the head-related transfer functions

PubMed Central

Ziegelwanger, Harald; Kreuzer, Wolfgang; Majdak, Piotr

2017-01-01

Head-related transfer functions (HRTFs) describe the directional filtering of the incoming sound caused by the morphology of a listener’s head and pinnae. When an accurate model of a listener’s morphology exists, HRTFs can be calculated numerically with the boundary element method (BEM). However, the general recommendation to model the head and pinnae with at least six elements per wavelength renders the BEM as a time-consuming procedure when calculating HRTFs for the full audible frequency range. In this study, a mesh preprocessing algorithm is proposed, viz., a priori mesh grading, which reduces the computational costs in the HRTF calculation process significantly. The mesh grading algorithm deliberately violates the recommendation of at least six elements per wavelength in certain regions of the head and pinnae and varies the size of elements gradually according to an a priori defined grading function. The evaluation of the algorithm involved HRTFs calculated for various geometric objects including meshes of three human listeners and various grading functions. The numerical accuracy and the predicted sound-localization performance of calculated HRTFs were analyzed. A-priori mesh grading appeared to be suitable for the numerical calculation of HRTFs in the full audible frequency range and outperformed uniform meshes in terms of numerical errors, perception based predictions of sound-localization performance, and computational costs. PMID:28239186

The FieldTrip-SimBio pipeline for EEG forward solutions.

PubMed

Vorwerk, Johannes; Oostenveld, Robert; Piastra, Maria Carla; Magyari, Lilla; Wolters, Carsten H

2018-03-27

Accurately solving the electroencephalography (EEG) forward problem is crucial for precise EEG source analysis. Previous studies have shown that the use of multicompartment head models in combination with the finite element method (FEM) can yield high accuracies both numerically and with regard to the geometrical approximation of the human head. However, the workload for the generation of multicompartment head models has often been too high and the use of publicly available FEM implementations too complicated for a wider application of FEM in research studies. In this paper, we present a MATLAB-based pipeline that aims to resolve this lack of easy-to-use integrated software solutions. The presented pipeline allows for the easy application of five-compartment head models with the FEM within the FieldTrip toolbox for EEG source analysis. The FEM from the SimBio toolbox, more specifically the St. Venant approach, was integrated into the FieldTrip toolbox. We give a short sketch of the implementation and its application, and we perform a source localization of somatosensory evoked potentials (SEPs) using this pipeline. We then evaluate the accuracy that can be achieved using the automatically generated five-compartment hexahedral head model [skin, skull, cerebrospinal fluid (CSF), gray matter, white matter] in comparison to a highly accurate tetrahedral head model that was generated on the basis of a semiautomatic segmentation with very careful and time-consuming manual corrections. The source analysis of the SEP data correctly localizes the P20 component and achieves a high goodness of fit. The subsequent comparison to the highly detailed tetrahedral head model shows that the automatically generated five-compartment head model performs about as well as a highly detailed four-compartment head model (skin, skull, CSF, brain). This is a significant improvement in comparison to a three-compartment head model, which is frequently used in praxis, since the importance of modeling the CSF compartment has been shown in a variety of studies. The presented pipeline facilitates the use of five-compartment head models with the FEM for EEG source analysis. The accuracy with which the EEG forward problem can thereby be solved is increased compared to the commonly used three-compartment head models, and more reliable EEG source reconstruction results can be obtained.

Farmers' Perceptions of Climate Variability and Factors Influencing Adaptation: Evidence from Anhui and Jiangsu, China

NASA Astrophysics Data System (ADS)

Kibue, Grace Wanjiru; Liu, Xiaoyu; Zheng, Jufeng; zhang, Xuhui; Pan, Genxing; Li, Lianqing; Han, Xiaojun

2016-05-01

Impacts of climate variability and climate change are on the rise in China posing great threat to agriculture and rural livelihoods. Consequently, China is undertaking research to find solutions of confronting climate change and variability. However, most studies of climate change and variability in China largely fail to address farmers' perceptions of climate variability and adaptation. Yet, without an understanding of farmers' perceptions, strategies are unlikely to be effective. We conducted questionnaire surveys of farmers in two farming regions, Yifeng, Jiangsu and Qinxi, Anhui achieving 280 and 293 responses, respectively. Additionally, we used climatological data to corroborate the farmers' perceptions of climate variability. We found that farmers' were aware of climate variability such that were consistent with climate records. However, perceived impacts of climate variability differed between the two regions and were influenced by farmers' characteristics. In addition, the vast majorities of farmers were yet to make adjustments in their farming practices as a result of numerous challenges. These challenges included socioeconomic and socio-cultural barriers. Results of logit modeling showed that farmers are more likely to adapt to climate variability if contact with extension services, frequency of seeking information, household heads' education, and climate variability perceptions are improved. These results suggest the need for policy makers to understand farmers' perceptions of climate variability and change in order to formulate policies that foster adaptation, and ultimately protect China's agricultural assets.

Farmers' Perceptions of Climate Variability and Factors Influencing Adaptation: Evidence from Anhui and Jiangsu, China.

PubMed

Kibue, Grace Wanjiru; Liu, Xiaoyu; Zheng, Jufeng; Zhang, Xuhui; Pan, Genxing; Li, Lianqing; Han, Xiaojun

2016-05-01

Impacts of climate variability and climate change are on the rise in China posing great threat to agriculture and rural livelihoods. Consequently, China is undertaking research to find solutions of confronting climate change and variability. However, most studies of climate change and variability in China largely fail to address farmers' perceptions of climate variability and adaptation. Yet, without an understanding of farmers' perceptions, strategies are unlikely to be effective. We conducted questionnaire surveys of farmers in two farming regions, Yifeng, Jiangsu and Qinxi, Anhui achieving 280 and 293 responses, respectively. Additionally, we used climatological data to corroborate the farmers' perceptions of climate variability. We found that farmers' were aware of climate variability such that were consistent with climate records. However, perceived impacts of climate variability differed between the two regions and were influenced by farmers' characteristics. In addition, the vast majorities of farmers were yet to make adjustments in their farming practices as a result of numerous challenges. These challenges included socioeconomic and socio-cultural barriers. Results of logit modeling showed that farmers are more likely to adapt to climate variability if contact with extension services, frequency of seeking information, household heads' education, and climate variability perceptions are improved. These results suggest the need for policy makers to understand farmers' perceptions of climate variability and change in order to formulate policies that foster adaptation, and ultimately protect China's agricultural assets.

Applications of Ni3Al Based Intermetallic Alloys—Current Stage and Potential Perceptivities

PubMed Central

Jozwik, Pawel; Polkowski, Wojciech; Bojar, Zbigniew

2015-01-01

The paper presents an overview of current and prospective applications of Ni3Al based intermetallic alloys—modern engineering materials with special properties that are potentially useful for both structural and functional purposes. The bulk components manufactured from these materials are intended mainly for forging dies, furnace assembly, turbocharger components, valves, and piston head of internal combustion engines. The Ni3Al based alloys produced by a directional solidification are also considered as a material for the fabrication of jet engine turbine blades. Moreover, development of composite materials with Ni3Al based alloys as a matrix hardened by, e.g., TiC, ZrO2, WC, SiC and graphene, is also reported. Due to special physical and chemical properties; it is expected that these materials in the form of thin foils and strips should make a significant contribution to the production of high tech devices, e.g., Micro Electro-Mechanical Systems (MEMS) or Microtechnology-based Energy and Chemical Systems (MECS); as well as heat exchangers; microreactors; micro-actuators; components of combustion chambers and gasket of rocket and jet engines as well components of high specific strength systems. Additionally, their catalytic properties may find an application in catalytic converters, air purification systems from chemical and biological toxic agents or in a hydrogen “production” by a decomposition of hydrocarbons.

Proposal of Interactive Applications to Enhance Student's Spatial Perception

ERIC Educational Resources Information Center

Moran, Samuel; Rubio, Ramon; Gallego, Ramon; Suarez, Javier; Martin, Santiago

2008-01-01

The aim of this series of applications is to enhance students' spatial perception capacity by means of exercises that require the student to concentrate on mentally recreating the figures represented. Each application is designed with an increasing level of difficulty, designed to increase the students' concentration and train their spatial…

Effects of Head-Mounted Display on the Oculomotor System and Refractive Error in Normal Adolescents.

PubMed

Ha, Suk-Gyu; Na, Kun-Hoo; Kweon, Il-Joo; Suh, Young-Woo; Kim, Seung-Hyun

2016-07-01

To investigate the clinical effects of head-mounted display on the refractive error and oculomotor system in normal adolescents. Sixty volunteers (age: 13 to 18 years) watched a three-dimensional movie and virtual reality application of head-mounted display for 30 minutes. The refractive error (diopters [D]), angle of deviation (prism diopters [PD]) at distance (6 m) and near (33 cm), near point of accommodation, and stereoacuity were measured before, immediately after, and 10 minutes after watching the head-mounted display. The refractive error was presented as spherical equivalent (SE). Refractive error was measured repeatedly after every 10 minutes when a myopic shift greater than 0.15 D was observed after watching the head-mounted display. The mean age of the participants was 14.7 ± 1.3 years and the mean SE before watching head-mounted display was -3.1 ± 2.6 D. One participant in the virtual reality application group was excluded due to motion sickness and nausea. After 30 minutes of watching the head-mounted display, the SE, near point of accommodation, and stereoacuity in both eyes did not change significantly (all P > .05). Immediately after watching the head-mounted display, esophoric shift was observed (0.6 ± 1.5 to 0.2 ± 1.5 PD), although it was not significant (P = .06). Transient myopic shifts of 17.2% to 30% were observed immediately after watching the head-mounted display in both groups, but recovered fully within 40 minutes after watching the head-mounted display. There were no significant clinical effects of watching head-mounted display for 30 minutes on the normal adolescent eye. Transient changes in refractive error and binocular alignment were noted, but were not significant. [J Pediatr Ophthalmol Strabismus. 2016;53(4):238-245.]. Copyright 2016, SLACK Incorporated.

Study on compensation algorithm of head skew in hard disk drives

NASA Astrophysics Data System (ADS)

Xiao, Yong; Ge, Xiaoyu; Sun, Jingna; Wang, Xiaoyan

2011-10-01

In hard disk drives (HDDs), head skew among multiple heads is pre-calibrated during manufacturing process. In real applications with high capacity of storage, the head stack may be tilted due to environmental change, resulting in additional head skew errors from outer diameter (OD) to inner diameter (ID). In case these errors are below the preset threshold for power on recalibration, the current strategy may not be aware, and drive performance under severe environment will be degraded. In this paper, in-the-field compensation of small DC head skew variation across stroke is proposed, where a zone table has been equipped. Test results demonstrating its effectiveness to reduce observer error and to enhance drive performance via accurate prediction of DC head skew are provided.

77 FR 65699 - Prospective Grant of Exclusive License: Development of Chemopreventive Treatments for Head and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-30

... Exclusive License: Development of Chemopreventive Treatments for Head and Neck Squamous Cell Carcinoma... Neck Squamous Cell Carcinoma'' (HHS Ref. No. E-302-2008/0) and PCT Patent Application No. PCT/IL2010... head and neck squamous cell carcinoma (HNSCC), a cancer occurring mostly in the mouth, it is frequently...

Smart optical writing head design for laser-based manufacturing

NASA Astrophysics Data System (ADS)

Amin, M. Junaid; Riza, Nabeel A.

2014-03-01

Proposed is a smart optical writing head design suitable for high precision industrial laser based machining and manufacturing applications. The design uses an Electronically Controlled Variable Focus Lens (ECVFL) which enables the highest achievable spatial resolution of writing head spot sizes for axial target distances reaching 8 meters. A proof-of-concept experiment is conducted using a visible wavelength laser with a collimated beam that is coupled to beam conditioning optics which includes an electromagnetically actuated deformable membrane liquid ECVFL cascaded with a bias convex lens of fixed focal length. Electronic tuning and control of the ECVFL keeps the laser writing head far-field spot beam radii under 1 mm that is demonstrated over a target range of 20 cm to 800 cm. Applications for the proposed writing head design, which can accommodate both continuous wave and pulsed wave sources, include laser machining, high precision industrial molding of components, as well as materials processing requiring material sensitive optical power density control.

Tackling the challenges of fully immersive head-mounted AR devices

NASA Astrophysics Data System (ADS)

Singer, Wolfgang; Hillenbrand, Matthias; Münz, Holger

2017-11-01

The optical requirements of fully immersive head mounted AR devices are inherently determined by the human visual system. The etendue of the visual system is large. As a consequence, the requirements for fully immersive head-mounted AR devices exceeds almost any high end optical system. Two promising solutions to achieve the large etendue and their challenges are discussed. Head-mounted augmented reality devices have been developed for decades - mostly for application within aircrafts and in combination with a heavy and bulky helmet. The established head-up displays for applications within automotive vehicles typically utilize similar techniques. Recently, there is the vision of eyeglasses with included augmentation, offering a large field of view, and being unobtrusively all-day wearable. There seems to be no simple solution to reach the functional performance requirements. Known technical solutions paths seem to be a dead-end, and some seem to offer promising perspectives, however with severe limitations. As an alternative, unobtrusively all-day wearable devices with a significantly smaller field of view are already possible.

A Grounded Theory Study of the Risks and Benefits Associated with the Use of Online Social Networking Applications in a Military Organization

ERIC Educational Resources Information Center

Webb, James O., Jr.

2012-01-01

There is a perception that there are risks and benefits associated with the use of online social networking media within a military organization. This research study explored this perception by investigating how employees use social networking applications and their perceptions of the benefits they receive. The study also assessed the measures…

Multispectral image-fused head-tracked vision system (HTVS) for driving applications

NASA Astrophysics Data System (ADS)

Reese, Colin E.; Bender, Edward J.

2001-08-01

Current military thermal driver vision systems consist of a single Long Wave Infrared (LWIR) sensor mounted on a manually operated gimbal, which is normally locked forward during driving. The sensor video imagery is presented on a large area flat panel display for direct view. The Night Vision and Electronics Sensors Directorate and Kaiser Electronics are cooperatively working to develop a driver's Head Tracked Vision System (HTVS) which directs dual waveband sensors in a more natural head-slewed imaging mode. The HTVS consists of LWIR and image intensified sensors, a high-speed gimbal, a head mounted display, and a head tracker. The first prototype systems have been delivered and have undergone preliminary field trials to characterize the operational benefits of a head tracked sensor system for tactical military ground applications. This investigation will address the advantages of head tracked vs. fixed sensor systems regarding peripheral sightings of threats, road hazards, and nearby vehicles. An additional thrust will investigate the degree to which additive (A+B) fusion of LWIR and image intensified sensors enhances overall driving performance. Typically, LWIR sensors are better for detecting threats, while image intensified sensors provide more natural scene cues, such as shadows and texture. This investigation will examine the degree to which the fusion of these two sensors enhances the driver's overall situational awareness.

Perception de la verticale avec Un cadre visuel solidaire de la tete: implications pour la conception des afficheurs de casques en ae’ronauflque (Perception of the Vertical With a Head-Mounted Visual Frame: Implication for the Design of Helmet-Mounted Displays in Aeronautics)

DTIC Science & Technology

2003-02-01

de celle de la tete. MWthodes Douze sujets, 9 hommes et 3 femmes, dg6s de 23 it 41 ans, se...qui donne la sensation de voir un 6cran informatique, centr6 sur l’axe interoculaire, d’une taille angulaire de 300 X 22,5’. L ’&ran virtuel apparait...inclin6s de faqon identique par rapport ýt la gravit6. Le premier essai 6tait toujours r6alis6 avec la tete droite . Ensuite, une nouvelle orientation de

Immersive viewing engine

NASA Astrophysics Data System (ADS)

Schonlau, William J.

2006-05-01

An immersive viewing engine providing basic telepresence functionality for a variety of application types is presented. Augmented reality, teleoperation and virtual reality applications all benefit from the use of head mounted display devices that present imagery appropriate to the user's head orientation at full frame rates. Our primary application is the viewing of remote environments, as with a camera equipped teleoperated vehicle. The conventional approach where imagery from a narrow field camera onboard the vehicle is presented to the user on a small rectangular screen is contrasted with an immersive viewing system where a cylindrical or spherical format image is received from a panoramic camera on the vehicle, resampled in response to sensed user head orientation and presented via wide field eyewear display, approaching 180 degrees of horizontal field. Of primary interest is the user's enhanced ability to perceive and understand image content, even when image resolution parameters are poor, due to the innate visual integration and 3-D model generation capabilities of the human visual system. A mathematical model for tracking user head position and resampling the panoramic image to attain distortion free viewing of the region appropriate to the user's current head pose is presented and consideration is given to providing the user with stereo viewing generated from depth map information derived using stereo from motion algorithms.

Comparison of optical see-through head-mounted displays for surgical interventions with object-anchored 2D-display

PubMed Central

Barthel, Alexander; Johnson, Alex; Osgood, Greg; Kazanzides, Peter; Navab, Nassir; Fuerst, Bernhard

2018-01-01

Purpose Optical see-through head-mounted displays (OST-HMD) feature an unhindered and instantaneous view of the surgery site and can enable a mixed reality experience for surgeons during procedures. In this paper, we present a systematic approach to identify the criteria for evaluation of OST-HMD technologies for specific clinical scenarios, which benefit from using an object-anchored 2D-display visualizing medical information. Methods Criteria for evaluating the performance of OST-HMDs for visualization of medical information and its usage are identified and proposed. These include text readability, contrast perception, task load, frame rate, and system lag. We choose to compare three commercially available OST-HMDs, which are representatives of currently available head-mounted display technologies. A multi-user study and an offline experiment are conducted to evaluate their performance. Results Statistical analysis demonstrates that Microsoft HoloLens performs best among the three tested OST-HMDs, in terms of contrast perception, task load, and frame rate, while ODG R-7 offers similar text readability. The integration of indoor localization and fiducial tracking on the HoloLens provides significantly less system lag in a relatively motionless scenario. Conclusions With ever more OST-HMDs appearing on the market, the proposed criteria could be used in the evaluation of their suitability for mixed reality surgical intervention. Currently, Microsoft HoloLens may be more suitable than ODG R-7 and Epson Moverio BT-200 for clinical usability in terms of the evaluated criteria. To the best of our knowledge, this is the first paper that presents a methodology and conducts experiments to evaluate and compare OST-HMDs for their use as object-anchored 2D-display during interventions. PMID:28343301

Development of new hard hat dimensions using user-centered design approach among oil palm harvesters.

PubMed

Mohd Shukoor, Nor Shuhada; Mohd Tamrin, Shamsul Bahri; Guan, Ng Yee; Mohd Suadi Nata, Dayana Hazwani

2018-05-22

Hard hats are among the personal protective equipment (PPE) used in many industries to reduce the impact of any falling object on the skull and also to prevent head and brain injuries. However, the practice of wearing a safety helmet during working hours is still low. This is due to the physical discomfort perceived by safety helmet users. Given the unpopularity of the current hard hat, the general perception of workers concerning its use and its measurements are the determining factors in the development of a new hard hat. A cross-sectional study was conducted in which 132 male oil palm harvesters between 19 and 60 years of age were selected from among the employees of the same oil palm harvesting company. A set of questionnaires was developed to collect their socio-demographic information as well as their perceptions of comfort and the prevalence of head injury. In addition, a set of measuring instruments, including Martin's anthropometry set, was used for head measurement and data collection in respect of the current hard hat. In this research, six respondents were randomly selected to attend an interview session for qualitative assessment.RESULTSBased on the questionnaires, the unpopularity in the use of the hard hat was largely influenced by factors related to poor design, in general, and, specifically, poor ventilation (64%), load (67% ), and physical discomfort (42% ). The measurements of the anthropometric parameters and the dimensions of the hard hat also showed a significant mismatch. The unpopularity of the current hard hat among oil palm harvesters stemmed from the discomfort from wearing, which showed that the development of a new hard hat could lead to better usage and the greater likelihood of wearing a hard hat throughout the working day.

Comparison of optical see-through head-mounted displays for surgical interventions with object-anchored 2D-display.

PubMed

Qian, Long; Barthel, Alexander; Johnson, Alex; Osgood, Greg; Kazanzides, Peter; Navab, Nassir; Fuerst, Bernhard

2017-06-01

Optical see-through head-mounted displays (OST-HMD) feature an unhindered and instantaneous view of the surgery site and can enable a mixed reality experience for surgeons during procedures. In this paper, we present a systematic approach to identify the criteria for evaluation of OST-HMD technologies for specific clinical scenarios, which benefit from using an object-anchored 2D-display visualizing medical information. Criteria for evaluating the performance of OST-HMDs for visualization of medical information and its usage are identified and proposed. These include text readability, contrast perception, task load, frame rate, and system lag. We choose to compare three commercially available OST-HMDs, which are representatives of currently available head-mounted display technologies. A multi-user study and an offline experiment are conducted to evaluate their performance. Statistical analysis demonstrates that Microsoft HoloLens performs best among the three tested OST-HMDs, in terms of contrast perception, task load, and frame rate, while ODG R-7 offers similar text readability. The integration of indoor localization and fiducial tracking on the HoloLens provides significantly less system lag in a relatively motionless scenario. With ever more OST-HMDs appearing on the market, the proposed criteria could be used in the evaluation of their suitability for mixed reality surgical intervention. Currently, Microsoft HoloLens may be more suitable than ODG R-7 and Epson Moverio BT-200 for clinical usability in terms of the evaluated criteria. To the best of our knowledge, this is the first paper that presents a methodology and conducts experiments to evaluate and compare OST-HMDs for their use as object-anchored 2D-display during interventions.

Xerostomia Quality of Life Scale (XeQoLS) questionnaire: validation of Italian version in head and neck cancer patients.

PubMed

Lastrucci, Luciana; Bertocci, Silvia; Bini, Vittorio; Borghesi, Simona; De Majo, Roberta; Rampini, Andrea; Gennari, Pietro Giovanni; Pernici, Paola

2018-01-01

To translate the Xerostomia Quality-of-Life Scale (XeQoLS) into Italian language (XeQoLS-IT). Xerostomia is the most relevant acute and late toxicity in patients with head and neck cancer treated with radiotherapy (RT). Patient-reported outcome (PRO) instruments are subjective report on patient perception of health status. The XeQoLS consists of 15 items and measures the impact of salivary gland dysfunction and xerostomia on the four major domains of oral health-related QoL. The XeQoLS-IT was created through a linguistic validation multi-step process: forward translation (TF), backward translation (TB) and administration of the questionnaire to 35 Italian patients with head and neck cancer. Translation was independently carried out by two radiation oncologists who were Italian native speakers. The two versions were compared and adapted to obtain a reconciled version, version 1 (V1). V1 was translated back into English by an Italian pro skilled in teaching English. After review of discrepancies and choice of the most appropriate wording for clarity and similarity to the original, version 2 (V2) was reached by consensus. To evaluate version 2, patients completed the XeQoLS-IT questionnaire and also underwent a cognitive debriefing. The questionnaire was considered simple by the patients. The clarity of the instructions and the easiness to answer questions had a mean value of 4.5 (± 0.71) on a scale from 1 to 5. A valid multi-step process led to the creation of the final version of the XeQoLS-IT, a suitable instrument for the perception of xerostomia in patients treated with RT.

El Impacto del Trastorno del Espectro Autista en la Familia: Mi Hijo Despues de la Crisis

ERIC Educational Resources Information Center

Rodriguez Carrion, Milagros

2012-01-01

The main purpose of this research is to know the perception of families who have a child diagnosed with autism and identify the strategies and process use to care of these children. We selected five Puerto Rican families who were head of household and had an autism child and through their voices and experiences we were able to conduct the…

Growing the Leadership Talent Pool: Perceptions of Heads, Middle Leaders and Classroom Teachers about Professional Development and Leadership Succession Planning within Their Own Schools

ERIC Educational Resources Information Center

Rhodes, Christopher; Brundrett, Mark

2009-01-01

This article reports on outcomes from a study funded by the National College for School Leadership designed to explore the factors that assist in the leadership development of teachers at a number of stages of their career development. More specifically, the study sought to identify issues associated with leadership talent identification,…

Spatial orientation in weightlessness and readaptation to earth's gravity

NASA Technical Reports Server (NTRS)

Young, L. R.; Oman, C. M.; Lichtenberg, B. K.; Watt, D. G. D.; Money, K. E.

1984-01-01

Unusual vestibular responses to head movements in weightlessness may produce spatial orientation illusions and symptoms of space motion sickness. An integrated set of experiments was performed during Spacelab 1, as well as before and after the flight, to evaluate responses mediated by the otolith organs and semicircular canals. A variety of measurements were used, including eye movements, postural control, perception of orientation, and susceptibility to space sickness.

Introduction to and Review of Simulator Sickness Research

DTIC Science & Technology

2005-04-01

other sensory systems play a role in the perception of motion. Kinesthetic receptors in the joints, muscles, and tendons signal limb, head, and body...is in general agreement about which categories of individuals are more susceptible than others. Gender . Females are reported to be more susceptible...and task variables. Pausch et al. (1992) reviewed several factors that evoke SS, with special emphasis given to simulator design issues. Gender . As

Child Behavior Problems, Teacher Executive Functions, and Teacher Stress in Head Start Classrooms

PubMed Central

Friedman-Krauss, Allison H.; Raver, C. Cybele; Neuspiel, Juliana M.; Kinsel, John

2017-01-01

Research Findings The current article explores the relationship between teachers’ perceptions of child behavior problems and preschool teacher job stress, as well as the possibility that teachers’ executive functions moderate this relationship. Data came from 69 preschool teachers in 31 early childhood classrooms in 4 Head Start centers and were collected using Web-based surveys and Web-based direct assessment tasks. Multilevel models revealed that higher levels of teachers’ perceptions of child behavior problems were associated with higher levels of teacher job stress and that higher teacher executive function skills were related to lower job stress. However, findings did not yield evidence for teacher executive functions as a statistical moderator. Practice or Policy Many early childhood teachers do not receive sufficient training for handling children’s challenging behaviors. Child behavior problems increase a teacher’s workload and consequently may contribute to feelings of stress. However, teachers’ executive function abilities may enable them to use effective, cognitive-based behavior management and instructional strategies during interactions with students, which may reduce stress. Providing teachers with training on managing challenging behaviors and enhancing executive functions may reduce their stress and facilitate their use of effective classroom practices, which is important for children’s school readiness skills and teachers’ health. PMID:28596698

Is it really "all in their heads"? How self-esteem predicts partner responsiveness.

PubMed

Cortes, Kassandra; Wood, Joanne V

2018-01-05

Having a responsive partner is important for the well-being of relationships. Unfortunately, people with low self-esteem (LSEs) perceive their partners to be less responsive than do people with high self-esteem (HSEs). Although the common assumption has been that LSEs' negative partner perceptions are "all in their heads"-a reflection of their negative self-projection-we argue that LSEs' views of lower partner responsiveness are, in fact, warranted. Across two studies (N Study1  = 122 couples, M age  = 22.28, 50% female; N Study2  = 73 couples, M age  = 19.96, 51% female), we examined LSEs' and HSEs' perceptions of their partners' responsiveness to their negative self-disclosures, comparing them with partners' reports (Study 1) and ratings from objective coders following a negative experience created in the lab (Study 2). Consistent with our hypothesis, partners of LSEs were less responsive than partners of HSEs to disclosers' negative self-disclosures, as rated by disclosers, listeners, and objective observers. Study 3 (N = 99, M age  = 33.19, 54% female) explored possible mechanisms behind these self-esteem differences. The finding that partners of LSEs (vs. HSEs) are less responsive may contribute to LSEs' poorer relationships. © 2018 Wiley Periodicals, Inc.

Perception of frequency, amplitude, and azimuth of a vibratory dipole source by the octavolateralis system of goldfish (Carassius auratus).

PubMed

Dailey, Deena D; Braun, Christopher B

2011-08-01

Goldfish (Carassius auratus) were conditioned to suppress respiration to a 40-Hz vibratory source and subsequently tested for stimulus generalization to frequency, stimulus amplitude, and position (azimuth). Animals completely failed to generalize to frequencies separated by octave intervals both lesser and greater than the CS. However, they did appear to generalize weakly to an aerial loudspeaker stimulus of the same frequency (40 Hz) after conditioning with an underwater vibratory source. Animals had a gradually decreasing amount of generalization to amplitude changes, suggesting a perceptual dimension of loudness. Animals generalized largely or completely to the same underwater source presented at a range of source azimuths. When these azimuths were presented at a transect of 3 cm, some animals did show decrements in generalization, while others did not. This suggests that although azimuth may be perceived more saliently at distances closer to a dipole source, perception of position is not immediately salient in conditioned vibratory source detection. Differential responding to test stimuli located toward the head or tail suggests the presence of perceptual differences between sources that are rostral or caudal with respect to the position of the animal or perhaps the head. PsycINFO Database Record (c) 2011 APA, all rights reserved.

Navigation of a virtual exercise environment with Microsoft Kinect by people post-stroke or with cerebral palsy.

PubMed

Pool, Sean M; Hoyle, John M; Malone, Laurie A; Cooper, Lloyd; Bickel, C Scott; McGwin, Gerald; Rimmer, James H; Eberhardt, Alan W

2016-04-08

One approach to encourage and facilitate exercise is through interaction with virtual environments. The present study assessed the utility of Microsoft Kinect as an interface for choosing between multiple routes within a virtual environment through body gestures and voice commands. The approach was successfully tested on 12 individuals post-stroke and 15 individuals with cerebral palsy (CP). Participants rated their perception of difficulty in completing each gesture using a 5-point Likert scale questionnaire. The "most viable" gestures were defined as those with average success rates of 90% or higher and perception of difficulty ranging between easy and very easy. For those with CP, hand raises, hand extensions, and head nod gestures were found most viable. For those post-stroke, the most viable gestures were torso twists, head nods, as well as hand raises and hand extensions using the less impaired hand. Voice commands containing two syllables were viable (>85% successful) for those post-stroke; however, participants with CP were unable to complete any voice commands with a high success rate. This study demonstrated that Kinect may be useful for persons with mobility impairments to interface with virtual exercise environments, but the effectiveness of the various gestures depends upon the disability of the user.

Sensory augmentation: integration of an auditory compass signal into human perception of space

PubMed Central

Schumann, Frank; O’Regan, J. Kevin

2017-01-01

Bio-mimetic approaches to restoring sensory function show great promise in that they rapidly produce perceptual experience, but have the disadvantage of being invasive. In contrast, sensory substitution approaches are non-invasive, but may lead to cognitive rather than perceptual experience. Here we introduce a new non-invasive approach that leads to fast and truly perceptual experience like bio-mimetic techniques. Instead of building on existing circuits at the neural level as done in bio-mimetics, we piggy-back on sensorimotor contingencies at the stimulus level. We convey head orientation to geomagnetic North, a reliable spatial relation not normally sensed by humans, by mimicking sensorimotor contingencies of distal sounds via head-related transfer functions. We demonstrate rapid and long-lasting integration into the perception of self-rotation. Short training with amplified or reduced rotation gain in the magnetic signal can expand or compress the perceived extent of vestibular self-rotation, even with the magnetic signal absent in the test. We argue that it is the reliability of the magnetic signal that allows vestibular spatial recalibration, and the coding scheme mimicking sensorimotor contingencies of distal sounds that permits fast integration. Hence we propose that contingency-mimetic feedback has great potential for creating sensory augmentation devices that achieve fast and genuinely perceptual experiences. PMID:28195187

[Habitus, capital and fields: the search for an acting head of the Hamburg Asylum Friedrichsberg in 1897].

PubMed

Sammet, Kai

2005-01-01

In 1897 Hamburg was in search of an Oberarzt for the asylum Friedrichsberg who should function as the acting head of the head Wilhelm Reye (1833-1912). This search was part of the intended reformation of the outmoded psychiatric care in Hamburg. During this application procedure the Hamburg Physikus John Wahncau examined all possible candidates and applicants. The article explores the election process by using some sociological categories developed by Pierre Bourdieu (habitus, capital, field). The author argues that not only meritocratic attributes led to the choice of one candidate, but also his functional "fitting" into the field in Hamburg.

Minor head injury: pathophysiological or iatrogenic sequelae?

PubMed Central

Newcombe, F; Rabbitt, P; Briggs, M

1994-01-01

This study addresses the possibility that cognitive sequelae--albeit of a transient or minor character--can be associated with mild head injury. Twenty men (aged 16-30 years of age), whose post-traumatic amnesia did not exceed eight hours, were examined within 48 hours of their accident and again one month later. This unselected sample had no previous history of head injury. A control group of 20 men of similar socioeconomic background, was selected from medical wards (where they had been admitted for orthopaedic treatment or a minor operation). They were also retested one month after the first examination. Neuropsychological tests were selected to measure abilities often compromised after significant head injury, namely memory and attention. The experimental component consisted of the fractionation of a complex skill (paced addition) to probe for deficits at different stages of information processing: perception and input into storage; search for and retrieval of information from working memory; and paced and unpaced addition. In general, no significant difference was found between the experimental and control groups, with the possible exception of an initial decrement on two working memory tasks: probe digits and a keeping track task (where the subject has to keep in mind and update a number of variables at the same time). The keeping track paradigm, ostensibly of ecological relevance, may well be worth further exploration in memory research, and in studies of more severely head-injured patients. It is further suggested that the appropriate management and counselling of mildly head-injured patients may help to avert symptoms that are of psychological rather than pathophysiological origin. PMID:8006652

Muecas: A Multi-Sensor Robotic Head for Affective Human Robot Interaction and Imitation

PubMed Central

Cid, Felipe; Moreno, Jose; Bustos, Pablo; Núñez, Pedro

2014-01-01

This paper presents a multi-sensor humanoid robotic head for human robot interaction. The design of the robotic head, Muecas, is based on ongoing research on the mechanisms of perception and imitation of human expressions and emotions. These mechanisms allow direct interaction between the robot and its human companion through the different natural language modalities: speech, body language and facial expressions. The robotic head has 12 degrees of freedom, in a human-like configuration, including eyes, eyebrows, mouth and neck, and has been designed and built entirely by IADeX (Engineering, Automation and Design of Extremadura) and RoboLab. A detailed description of its kinematics is provided along with the design of the most complex controllers. Muecas can be directly controlled by FACS (Facial Action Coding System), the de facto standard for facial expression recognition and synthesis. This feature facilitates its use by third party platforms and encourages the development of imitation and of goal-based systems. Imitation systems learn from the user, while goal-based ones use planning techniques to drive the user towards a final desired state. To show the flexibility and reliability of the robotic head, the paper presents a software architecture that is able to detect, recognize, classify and generate facial expressions in real time using FACS. This system has been implemented using the robotics framework, RoboComp, which provides hardware-independent access to the sensors in the head. Finally, the paper presents experimental results showing the real-time functioning of the whole system, including recognition and imitation of human facial expressions. PMID:24787636

Developments in deep brain stimulation using time dependent magnetic fields

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

Crowther, L.J.; Nlebedim, I.C.; Jiles, D.C.

2012-03-07

The effect of head model complexity upon the strength of field in different brain regions for transcranial magnetic stimulation (TMS) has been investigated. Experimental measurements were used to verify the validity of magnetic field calculations and induced electric field calculations for three 3D human head models of varying complexity. Results show the inability for simplified head models to accurately determine the site of high fields that lead to neuronal stimulation and highlight the necessity for realistic head modeling for TMS applications.

Developments in deep brain stimulation using time dependent magnetic fields

NASA Astrophysics Data System (ADS)

Crowther, L. J.; Nlebedim, I. C.; Jiles, D. C.

2012-04-01

The effect of head model complexity upon the strength of field in different brain regions for transcranial magnetic stimulation (TMS) has been investigated. Experimental measurements were used to verify the validity of magnetic field calculations and induced electric field calculations for three 3D human head models of varying complexity. Results show the inability for simplified head models to accurately determine the site of high fields that lead to neuronal stimulation and highlight the necessity for realistic head modeling for TMS applications.

Pulse laser head with monolithic thermally bonded microchip operating at 1.5 μm wavelength

NASA Astrophysics Data System (ADS)

Młyńczak, Jarosław; Kopczyński, Krzysztof; Belghachem, Nabil; Kisielewski, Jarosław; Stepień, Ryszard; Wychowaniec, Marek; Galas, Jacek; Litwin, Dariusz; CzyŻewski, Adam

2016-12-01

On the basis of thermally bonded Er,Yb:glass/Co:MALO microchip a laser head pumped by fiber coupled laser diode was designed. The performance of the laser head were investigated and the main output parameters were determined. The energy over 40 μJ in 3.8 ns pulse with repetition rate of 0.735 kHz was achieved. The laser head characterized by such parameters can successfully be used in tele-detection applications.

Assessment of the safety and efficacy of three concentrations of topical ivermectin lotion as a treatment for head lice infestation.

PubMed

Meinking, Terri L; Mertz-Rivera, Kamara; Villar, Maria Elena; Bell, Margie

2013-01-01

Ivermectin is a broad-spectrum parasiticide in widespread systemic use, including as an off-label treatment for head lice infestation. The potential of the topical use of ivermectin as a treatment for head lice infestation was suggested by an in vitro report of a novel lotion formulation. This study investigated the relative effectiveness of three ivermectin lotion concentrations (0.15, 0.25, and 0.5%) compared with vehicle placebo in eliminating head lice infestation. In this randomized, blinded study, 78 head lice-infested subjects, aged 2-62 years, received a single, 10-minute application of product on day 1. Evaluations were completed at two and six hours post-application, and on days 2, 8 (±1), and 15 (+2). Safety was assessed according to the evaluations of trained observers and adverse event (AE) reports. Efficacy was assessed according to scalp and hair examinations. Compared with placebo, all ivermectin concentrations resulted in the statistically significant (P ≤ 0.003) eradication of head lice through to day 15, with the highest level of eradication (73.7%) in subjects who received the 0.5% concentration. The severity of pruritus decreased from baseline in all treatment groups, including the placebo group, from six hours post-treatment to day 15, with the greatest reduction in the 0.5% concentration group. No ocular irritation was observed. All three ivermectin treatment strengths and vehicle were well tolerated. A single application of a 0.5% concentration of this ivermectin lotion formulation shows promise as a safe and effective treatment for head lice infestation and the associated signs of pruritus. © 2013 The International Society of Dermatology.

A computer-based simulation of obstetric forceps placement.

PubMed

Lapeer, Rudy; Audinis, Vilius; Gerikhanov, Zelimkhan; Dupuis, Olivier

2014-01-01

Obstetric forceps are commonly used when the expulsion of the baby during childbirth fails to progress. When the two forceps blades are applied correctly, i.e. symmetrically, the inner surface of each blade maximises the area in contact with the fetal head. On the contrary, when the blades are applied asymmetrically, the contact areas between the inner surface of the blades and the fetal head are minimal and at distinct locations at the left and right sides of the fetal head. It is therefore assumed in the field of obstetrics that asymmetric application is bound to cause intra-cranial damage due to significantly higher shear forces and significant deformation of the fetal cranial bones as compared to symmetric application. In this paper we present the first of a series of studies to analyse the mechanical contact between head and forceps under different conditions using finite element analysis. We used high fidelity mesh models of a fetal skull and obstetric forceps. The fetal cranial material properties are known from previous studies. We observed significantly higher deformations and stresses for the asymmetric application of the blades as compared to symmetric placement.

Eye Tracking and Head Movement Detection: A State-of-Art Survey

PubMed Central

2013-01-01

Eye-gaze detection and tracking have been an active research field in the past years as it adds convenience to a variety of applications. It is considered a significant untraditional method of human computer interaction. Head movement detection has also received researchers' attention and interest as it has been found to be a simple and effective interaction method. Both technologies are considered the easiest alternative interface methods. They serve a wide range of severely disabled people who are left with minimal motor abilities. For both eye tracking and head movement detection, several different approaches have been proposed and used to implement different algorithms for these technologies. Despite the amount of research done on both technologies, researchers are still trying to find robust methods to use effectively in various applications. This paper presents a state-of-art survey for eye tracking and head movement detection methods proposed in the literature. Examples of different fields of applications for both technologies, such as human-computer interaction, driving assistance systems, and assistive technologies are also investigated. PMID:27170851

Liquid Biopsy in Head and Neck Cancer: Promises and Challenges.

PubMed

Nonaka, T; Wong, D T W

2018-06-01

Head and neck cancer is the sixth most common cancer worldwide. It remains one of the leading causes of death, and its early detection is crucial. Liquid biopsy has emerged as a promising tool for detecting and monitoring the disease status of patients with early and advanced cancers. Circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), and exosomal miRNAs have received enormous attention because of their apparent clinical implications. Analyses of these circulating biomarkers have paved the way for novel therapeutic approaches and precision medicine. A growing number of reports have implicated the use of circulating biomarkers for detection, treatment planning, response monitoring, and prognosis assessment. Although these new biomarkers can provide a wide range of possible clinical applications, no validated circulating biomarkers have yet been integrated into clinical practice for head and neck cancer. In this review, we summarize the current knowledge of circulating biomarkers in this field, focusing on their feasibility, limitations, and key areas of clinical applications. We also highlight recent advances in salivary diagnostics and their potential application in head and neck cancer.

7 CFR 868.311 - Grades and grade requirements for the class Second Head Milled Rice. (See also § 868.315.)

Code of Federal Regulations, 2011 CFR

2011-01-01

... Head Milled Rice. (See also § 868.315.) 868.311 Section 868.311 Agriculture Regulations of the... COMMODITIES United States Standards for Milled Rice Principles Governing Application of Standards § 868.311 Grades and grade requirements for the class Second Head Milled Rice. (See also § 868.315.) Grades, Grade...

7 CFR 868.311 - Grades and grade requirements for the class Second Head Milled Rice. (See also § 868.315.)

Code of Federal Regulations, 2010 CFR

2010-01-01

... Head Milled Rice. (See also § 868.315.) 868.311 Section 868.311 Agriculture Regulations of the... COMMODITIES United States Standards for Milled Rice Principles Governing Application of Standards § 868.311 Grades and grade requirements for the class Second Head Milled Rice. (See also § 868.315.) Grades, Grade...

The head injured adolescent: a case report and review of the issues.

PubMed

Reiter, S; Kutcher, S P

1990-11-01

Closed head injuries in adolescents are a common problem with potentially disastrous consequences to multiple areas of functioning. Through a case presentation and literature review, this paper considers treatment issues and research applications in an adolescent population with closed head injuries. Suggestions for understanding the symptom constellations are made and directions for future research and service delivery are given.

Anthropometry: Basic Studies and Applications. Volume 2, 1976 - July 1978

DTIC Science & Technology

1978-08-01

available anthtcpcmetry of the head and face of member ASCC nations, demonstrates their similarities, and tests the theoretical suitability of a Poyal...Helmets, ’light clothina. Standardization, military forces (Foreign) , Military forces (United otates). Flight crews. Head (A na tomy) , Sizes (Dimensions...sioloay) , Head (Anatomy) , Face(Anatomy), Arms (Anatcmy) , Legs, Hands, Feet, Measurement, Sizes (t intensions) Tdentifiers: Ace

Biomechanical versus inertial information: stable individual differences in perception of self-rotation.

PubMed

Bruggeman, Hugo; Piuneu, Vadzim S; Rieser, John J; Pick, Herbert L

2009-10-01

When turning without vision or audition, people tend to perceive their locomotion as a change in heading relative to objects in the remembered surroundings. Such perception of self-rotation depends on sensitivity to information for movement from biomechanical activity of the locomotor system or from inertial activation of the vestibular and postural systems. The authors report 3 experiments that investigated the relative contributions of biomechanical and inertial information to perceiving the speed of self-rotation. Using a circular treadmill, the proportions of the 2 sources of proprioceptive information were varied, creating walking conditions with a constant rate of biomechanical activity but with variable speeds of rotation relative to inertial space. The results reveal stable individual differences in sensitivity to information for the perception of locomotion. Just more than half of the participants based their perceived speed of self-rotation on biomechanical information, whereas the others based theirs on inertial information. PsycINFO Database Record (c) 2009 APA, all rights reserved.

The impact of HIV infection on society's perception of clinical trials.

PubMed

Levine, R J

1994-06-01

All international codes of research ethics and virtually all national legislation and regulation in the field of research involving human subjects project an attitude of protectionism. Written with the aim of avoiding a repetition of atrocities like those committed by the Nazi physician-researchers, calamities like the thalidomide experience, or ethical violations like those of the Tuskegee syphilis study, their dominant concerns are the protection of individuals from injury and from exploitation. In recent years, however, society's perception of clinical research has shifted dramatically. Now, largely as a consequence of the efforts of the AIDS activists, clinical research is widely perceived as benign and beneficial. Although this shift in attitude has resulted in some important improvements in research policies and practices, this new perception is just as wrong-headed as was the earlier excessive protectionism. It is necessary to maintain a balanced perspective; our policies should encourage the conduct of ethical research while maintaining the vigilance necessary to safeguard the rights and welfare of the subjects.

Using visible speech to train perception and production of speech for individuals with hearing loss.

PubMed

Massaro, Dominic W; Light, Joanna

2004-04-01

The main goal of this study was to implement a computer-animated talking head, Baldi, as a language tutor for speech perception and production for individuals with hearing loss. Baldi can speak slowly; illustrate articulation by making the skin transparent to reveal the tongue, teeth, and palate; and show supplementary articulatory features, such as vibration of the neck to show voicing and turbulent airflow to show frication. Seven students with hearing loss between the ages of 8 and 13 were trained for 6 hours across 21 weeks on 8 categories of segments (4 voiced vs. voiceless distinctions, 3 consonant cluster distinctions, and 1 fricative vs. affricate distinction). Training included practice at the segment and the word level. Perception and production improved for each of the 7 children. Speech production also generalized to new words not included in the training lessons. Finally, speech production deteriorated somewhat after 6 weeks without training, indicating that the training method rather than some other experience was responsible for the improvement that was found.

Burden of focal cryoablation versus brachytherapy versus active surveillance in the treatment of very low-risk prostate cancer: a preliminary head-to-head comprehensive assessment.

PubMed

de Cerqueira, M A; Laranja, W W; Sanches, B C F; Monti, C R; Reis, L O

2015-11-01

Focal cryoablation (FC), brachytherapy (B) and active surveillance (AS) were offered to patients diagnosed with very low-risk prostate cancer (VLRPC) in an equal access protocol. Comprehensive validated self-report questionnaires accessed patients' erectile (IIEF-5) and voiding (IPSS) functions, Beck scales measured anxiety (BAI), hopelessness (BHS) and depression (BDI), SF-36 reflected patients' quality of life added to the emotional thermometers including five visual analogue scales (distress, anxiety, depression, anger and need for help). Kruskal-Wallis or ANOVA tests and Spearman's correlations were obtained among groups and studied variables. Thirty patients were included, median follow-up 18 months (15-21). Those on AS (n = 11) were older, presented higher hopelessness (BHS) and lower general health perceptions (SF-36) scores than patients opting for FC (n = 10) and B (n = 9), P = 0.0014, P = 0.0268 and P = 0.0168 respectively. Patients on B had higher IPSS scores compared to those under FC and AC, P = 0.0223. For all 30 included patients, Spearman's correlation (rs ) was very strong between BHS and general health perceptions (rs  = -0.800, P < 0.0001), and weak/moderate between age and BHS (rs  = 0.405, P = 0.026) and age and general health perceptions (rs  = -0.564, P = 0.001). The sample power was >60%. To be considered in patients' counselling and care, current study supports the hypothesis that even VLRPC when untreated undermines psychosocial domains. © 2015 John Wiley & Sons Ltd.

Naegele Forceps Delivery and Association between Morbidity and the Number of Forceps Traction Applications: A Retrospective Study.

PubMed

Matsumoto, Naoki; Takenaka, Toshifumi; Ikeda, Nobuyuki; Yazaki, Satoshi; Sato, Yuichi

2015-01-01

To present the method of Naegele forceps delivery clinically practiced by the lead author, its success rate, and morbidity and to evaluate the relationship between morbidity and the number of forceps traction applications. Naegele forceps delivery was performed when the fetal head reached station +2 cm, the forceps were applied in the maternal pelvic application, and traction was slowly and gently performed. In the past two years, Naegele forceps delivery was attempted by the lead author in 87 cases, which were retrospectively reviewed. The numbers of traction applications were one in 64.7% of cases, two in 24.7%, and three or more in 10.7%. The success rate was 100%. No severe morbidity was observed in mothers or neonates. Neonatal facial injury occurred most commonly in cases with fetal head malrotation, elevated numbers of traction applications, and maternal complications. Umbilical artery acidemia most commonly occurred in cases with nonreassuring fetal status. The significant crude odds ratio for three or more traction applications was 20 in cases with malrotation. Naegele forceps delivery has a high success rate, but multiple traction applications will sometimes be required, particularly in cases with malrotation. Malrotation and elevated numbers of traction applications may lead to neonatal head damage.

A simple integrative method for presenting head-contingent motion parallax and disparity cues on intel x86 processor-based machines.

PubMed

Szatmary, J; Hadani, I; Julesz, B

1997-01-01

Rogers and Graham (1979) developed a system to show that head-movement-contingent motion parallax produces monocular depth perception in random dot patterns. Their display system comprised an oscilloscope driven by function generators or a special graphics board that triggered the X and Y deflection of the raster scan signal. Replication of this system required costly hardware that is no longer on the market. In this paper the Rogers-Graham method is reproduced with an Intel processor based IBM PC compatible machine with no additional hardware cost. An adapted joystick sampled through the standard game-port can serve as a provisional head-movement sensor. Monitor resolution for displaying motion is effectively enhanced 16 times by the use of anti-aliasing, enabling the display of thousands of random dots in real-time with a refresh rate of 60 Hz or above. A color monitor enables the use of the anaglyph method, thus combining stereoscopic and monocular parallax on a single display without the loss of speed. The power of this system is demonstrated by a psychophysical measurement in which subjects nulled head-movement-contingent illusory parallax, evoked by a static stereogram, with real parallax. The amount of real parallax required to null the illusory stereoscopic parallax monotonically increased with disparity.

GPS interferometric attitude and heading determination: Initial flight test results

NASA Technical Reports Server (NTRS)

Vangraas, Frank; Braasch, Michael

1991-01-01

Attitude and heading determination using GPS interferometry is a well-understood concept. However, efforts have been concentrated mainly in the development of robust algorithms and applications for low dynamic, rigid platforms (e.g., shipboard). This paper presents results of what is believed by the authors to be the first realtime flight test of a GPS attitude and heading determination system. The system is installed in Ohio University's Douglas DC-3 research aircraft. Signals from four antennas are processed by an Ashtech 3DF 24-channel GPS receiver. Data from the receiver are sent to a microcomputer for storage and further computations. Attitude and heading data are sent to a second computer for display on a software generated artificial horizon. Demonstration of this technique proves its candidacy for augmentation of aircraft state estimation for flight control and navigation as well as for numerous other applications.

Role of Cerebellum in Motion Perception and Vestibulo-ocular Reflex—Similarities and Disparities

PubMed Central

Shaikh, Aasef G.; Palla, Antonella; Marti, Sarah; Olasagasti, Itsaso; Optican, Lance M.; Zee, David S.; Straumann, Dominik

2012-01-01

Vestibular velocity storage enhances the efficacy of the angular vestibulo-ocular reflex (VOR) during relatively low-frequency head rotations. This function is modulated by GABA-mediated inhibitory cerebellar projections. Velocity storage also exists in perceptual pathway and has similar functional principles as VOR. However, it is not known whether the neural substrate for perception and VOR overlap. We propose two possibilities. First, there is the same velocity storage for both VOR and perception; second, there are nonoverlapping neural networks: one might be involved in perception and the other for the VOR. We investigated these possibilities by measuring VOR and perceptual responses in healthy human subjects during whole-body, constant-velocity rotation steps about all three dimensions (yaw, pitch, and roll) before and after 10 mg of 4-aminopyridine (4-AP). 4-AP, a selective blocker of inward rectifier potassium conductance, can lead to increased synchronization and precision of Purkinje neuron discharge and possibly enhance the GABAergic action. Hence 4-AP could reduce the decay time constant of the perceived angular velocity and VOR. We found that 4-AP reduced the decay time constant, but the amount of reduction in the two processes, perception and VOR, was not the same, suggesting the possibility of nonoverlapping or partially overlapping neural substrates for VOR and perception. We also noted that, unlike the VOR, the perceived angular velocity gradually built up and plateau prior to decay. Hence, the perception pathway may have additional mechanism that changes the dynamics of perceived angular velocity beyond the velocity storage. 4-AP had no effects on the duration of build-up of perceived angular velocity, suggesting that the higher order processing of perception, beyond the velocity storage, might not occur under the influence of mechanism that could be influenced by 4-AP. PMID:22777507

Pain modulation during drives through cold and hot virtual environments.

PubMed

Mühlberger, Andreas; Wieser, Matthias J; Kenntner-Mabiala, Ramona; Pauli, Paul; Wiederhold, Brenda K

2007-08-01

Evidence exists that virtual worlds reduce pain perception by providing distraction. However, there is no experimental study to show that the type of world used in virtual reality (VR) distraction influences pain perception. Therefore, we investigated whether pain triggered by heat or cold stimuli is modulated by "warm "or "cold " virtual environments and whether virtual worlds reduce pain perception more than does static picture presentation. We expected that cold worlds would reduce pain perception from heat stimuli, while warm environments would reduce pain perception from cold stimuli. Additionally, both virtual worlds should reduce pain perception in general. Heat and cold pain stimuli thresholds were assessed outside VR in 48 volunteers in a balanced crossover design. Participants completed three 4-minute assessment periods: virtual "walks " through (1) a winter and (2) an autumn landscape and static exposure to (3) a neutral landscape. During each period, five heat stimuli or three cold stimuli were delivered via a thermode on the participant's arm, and affective and sensory pain perceptions were rated. Then the thermode was changed to the other arm, and the procedure was repeated with the opposite pain stimuli (heat or cold). We found that both warm and cold virtual environments reduced pain intensity and unpleasantness for heat and cold pain stimuli when compared to the control condition. Since participants wore a head-mounted display (HMD) in both the control condition and VR, we concluded that the distracting value of virtual environments is not explained solely by excluding perception of the real world. Although VR reduced pain unpleasantness, we found no difference in efficacy between the types of virtual world used for each pain stimulus.

Depressive Symptoms and Perceptions of Child Difficulty Are Associated with Less Responsive Feeding Behaviors in an Observational Study of Low-Income Mothers.

PubMed

Elias, Cindy V; Power, Thomas G; Beck, Ashley E; Goodell, L Suzanne; Johnson, Susan L; Papaioannou, Maria A; Hughes, Sheryl O

2016-12-01

Maternal depressive symptoms and perceptions of child difficulty are associated with negative effects on general development and cognitive functioning in children. The study examined associations between maternal depressive symptoms, perceptions of child difficulty, and maternal feeding behaviors in a population at elevated risk for childhood obesity. Participants were 138 low-income black and Hispanic mothers and their children (ages 3-5) participating in an observational study of mealtimes among Head Start families. Three dinnertime observations were conducted over 2 weeks on each family and audio/videotaped for coding. Coding included eating influence attempts and other food- and nonfood-related interactions exhibited by the mother during dinner. Mothers completed questionnaires on depressive symptoms and perceptions of child difficulty. Linear regressions were conducted, examining associations between maternal depressive symptoms, perceptions of child difficulty, and coded parent feeding behaviors. Mothers reporting higher levels of depressive symptoms used more verbal pressure to get their child to eat during meals, were more likely to discourage child independence, and less likely to enforce table manners. Mothers reporting higher perceptions of child difficulty were less likely to have nonfood-related discussions during meals and to try to get the child to eat a different food. This study is one of the first to investigate associations between maternal depression, perceptions of child difficulty, and mother's feeding behaviors during meals using observational methodology. These results may help researchers identify specific parental characteristics and feeding practices on which to intervene when developing tailored intervention programs for reducing childhood obesity.

The Effect of Activities in Robotic Applications on Students' Perception on the Nature of Science and Students' Metaphors Related to the Concept of Robot

ERIC Educational Resources Information Center

Korkmaz, Özgen; Altun, Halis; Usta, Ertugrul; Özkaya, Armagan

2014-01-01

The purpose of this study is to examine students' perceptions of the nature of science and metaphors related to the concept of robot, to determine the differentiation in these perceptions and metaphors resulting from LEGO NXT robot applications, and to share some good examples of education-oriented activities with robots. In this study, a hybrid…

Integrated titer plate-injector head for microdrop array preparation, storage and transfer

DOEpatents

Swierkowski, Stefan P.

2000-01-01

An integrated titer plate-injector head for preparing and storing two-dimensional (2-D) arrays of microdrops and for ejecting part or all of the microdrops and inserting same precisely into 2-D arrays of deposition sites with micrometer precision. The titer plate-injector head includes integrated precision formed nozzles with appropriate hydrophobic surface features and evaporative constraints. A reusable pressure head with a pressure equalizing feature is added to the titer plate to perform simultaneous precision sample ejection. The titer plate-injector head may be utilized in various applications including capillary electrophoresis, chemical flow injection analysis, microsample array preparation, etc.

Application of a frequency distribution method for determining instars of the beet armyworm (Lepidoptera: Noctuidae) from widths of cast head capsules

Treesearch

Y. Chen; S. J. Seybold

2013-01-01

Instar determination of field-collected insect larvae has generally been based on the analysis of head capsule width frequency distributions or bivariate plotting, but few studies have tested the validity of such methods. We used head capsules from exuviae of known instars of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae),...

15 CFR 241.4 - Application of tolerance for “diameter of head.”

Code of Federal Regulations, 2010 CFR

2010-01-01

... the mean of the average diameters from inside to inside of staves at the inner edges of the heads. (2..., one taken from inside to inside of staves at the inner edge of the head, the other from inside to inside of staves at the inner edge of the croze ring, or from inside to inside of staves at a point where...

Resolution of sensory ambiguities for gaze stabilization requires a second neural integrator

NASA Technical Reports Server (NTRS)

Green, Andrea M.; Angelaki, Dora E.

2003-01-01

The ability to simultaneously move in the world and maintain stable visual perception depends critically on the contribution of vestibulo-ocular reflexes (VORs) to gaze stabilization. It is traditionally believed that semicircular canal signals drive compensatory responses to rotational head disturbances (rotational VOR), whereas otolith signals compensate for translational movements [translational VOR (TVOR)]. However, a sensory ambiguity exists because otolith afferents are activated similarly during head translations and reorientations relative to gravity (i.e., tilts). Extra-otolith cues are, therefore, necessary to ensure that dynamic head tilts do not elicit a TVOR. To investigate how extra-otolith signals contribute, we characterized the temporal and viewing distance-dependent properties of a TVOR elicited in the absence of a lateral acceleration stimulus to the otoliths during combined translational/rotational motion. We show that, in addition to otolith signals, angular head position signals derived by integrating sensory canal information drive the TVOR. A physiological basis for these results is proposed in a model with two distinct integration steps. Upstream of the well known oculomotor velocity-to-position neural integrator, the model incorporates a separate integration element that could represent the "velocity storage integrator," whose functional role in the oculomotor system has so far remained controversial. We propose that a key functional purpose of the velocity storage network is to temporally integrate semicircular canal signals, so that they may be used to extract translation information from ambiguous otolith afferent signals in the natural and functionally relevant bandwidth of head movements.

[Clinical application and optimization of HEAD-US quantitative ultrasound assessment scale for hemophilic arthropathy].

PubMed

Li, J; Guo, X J; Ding, X L; Lyu, B M; Xiao, J; Sun, Q L; Li, D S; Zhang, W F; Zhou, J C; Li, C P; Yang, R C

2018-02-14

Objective: To assess the feasibility of HEAD-US scale in the clinical application of hemophilic arthropathy (HA) and propose an optimized ultrasound scoring system. Methods: From July 2015 to August 2017, 1 035 joints ultrasonographic examinations were performed in 91 patients. Melchiorre, HEAD-US (Hemophilic Early Arthropathy Detection with UltraSound) and HEAD-US-C (HEAD-US in China) scale scores were used respectively to analyze the results. The correlations between three ultrasound scales and Hemophilia Joint Health Scores (HJHS) were evaluated. The sensitivity differences of the above Ultrasonic scoring systems in evaluation of HA were compared. Results: All the 91 patients were male, with median age of 16 (4-55) years old, including 86 cases of hemophilia A and 5 cases hemophilia B. The median ( P 25 , P 75 ) of Melchiorre, HEAD-US and HEAD-US-C scores of 1 035 joints were 2(0,6), 1(0,5) and 2(0,6), respectively, and the correlation coefficients compared with HJHS was 0.747, 0.762 and 0.765 respectively, with statistical significance ( P <0.001). The positive rates of Melchiorre, HEAD-US-C and HEAD-US scale score were 63.0% (95% CI 59.7%-65.9%), 59.5% (95% CI 56.5%-62.4%) and 56.6% (95% CI 53.6%-59.6%) respectively, and the difference was statistically significant ( P <0.001). Even for 336 cases of asymptomatic joints, the positive rates of Melchiorre, HEAD-US-C and HEAD-US scale score were 25.0% (95% CI 20.6%-29.6%), 17.0% (95% CI 12.6%-21.1%) and 11.9% (95% CI 8.4%-15.7%) respectively, and the difference was statistically significant ( P <0.001). There were significant changes ( P <0.05) in the ultrasonographic score of HA before and after onset of hemorrhage in 107 joints of 40 patients. The difference in variation amplitude of HEAD-US-C scores and HEAD-US scores before and after joint bleeding was statistically significant ( P <0.001). Conclusion: Compared with Melchiorre, there were similar good correlations between HEAD-US, HEAD-US-C and HJHS. HEAD-US ultrasound scoring system is quick, convenient and simple to use. The optimized HEAD-US-C scale score is more sensitive than HEAD-US, especially for patients with HA who have subclinical state, which make up for insufficiency of sensitivity in HEAD-US scoring system.

[Applications of 3D printing technology in teaching of oromaxillofacial head and neck surgical oncology].

PubMed

Ruan, Min; Ji, Tong; Zhang, Chen-Ping

2016-12-01

With the increasing maturation of 3D printing technology, as well as its application in various industries, investigation of 3D printing technology into clinic medical education becomes an important task of the current medical education. The teaching content of oromaxillofacial head and neck surgical oncology is complicated and diverse, making lower understanding/memorizing efficiency and insufficient skill training. To overcome the disadvantage of traditional teaching method, it is necessary to introduce 3D printing technique into teaching of oromaxillofacial head and neck surgical oncology, in order to improve the teaching quality and problem solving capabilities, and finally promote cultivation of skilled and innovative talents.

Cognition 2035: Surviving a Complex Environment Through Unprecedented Intelligence

DTIC Science & Technology

2009-02-12

the invention of synthetic telepathy , including mind-to-mind or telepathic dialogue. This type of development would have obvious military and... telepathy . They have this odd way of cocking their head in a certain way whenever they want to access information they don’t already have in their own...accessible through cognition and might include synthetic sensory perception beamed direct to the user’s senses. Wider related ICT developments might include

What Makes My School a Good Training Ground for Leadership Development?: The Perceptions of Heads, Middle Leaders and Classroom Teachers from 70 Contextually Different Primary and Secondary Schools in England

ERIC Educational Resources Information Center

Rhodes, Christopher; Brundrett, Mark

2008-01-01

This article reports on outcomes from a study funded by the National College for School Leadership designed to explore leadership talent identification, development, succession and retention in contextually different primary and secondary schools in England. It draws upon this larger project and offers evidence not seen before elsewhere. It deals…

Performance considerations for high-definition head-mounted displays

NASA Technical Reports Server (NTRS)

Edwards, Oliver J.; Larimer, James; Gille, Jennifer

1992-01-01

Design image-optimization for helmet-mounted displays (HMDs) for military systems is presently discussed within the framework of a systems-engineering approach that encompasses (1) a description of natural targets in the field; (2) the characteristics of human visual perception; and (3) device specifications that directly relate to these ecological and human-factors parameters. Attention is given to target size and contrast and the relationship of the modulation transfer function to image resolution.

Helmet-Mounted Displays: Sensation, Perception and Cognition Issues

DTIC Science & Technology

2009-01-01

Inc., web site: http://www.metavr.com/ technology/ papers /syntheticvision.html Helmetag, A., Halbig, C., Kubbat, W., and Schmidt, R. (1999...system-of-systems.” One integral system is a “head-borne vision enhancement” system (an HMD) that provides fused I2/ IR sensor imagery (U.S. Army Natick...Using microwave, radar, I2, infrared ( IR ), and other technology-based imaging sensors, the “seeing” range of the human eye is extended into the

Image-guided surgery.

PubMed

Wagner, A; Ploder, O; Enislidis, G; Truppe, M; Ewers, R

1996-04-01

Interventional video tomography (IVT), a new imaging modality, achieves virtual visualization of anatomic structures in three dimensions for intraoperative stereotactic navigation. Partial immersion into a virtual data space, which is orthotopically coregistered to the surgical field, enhances, by means of a see-through head-mounted display (HMD), the surgeon's visual perception and technique by providing visual access to nonvisual data of anatomy, physiology, and function. The presented cases document the potential of augmented reality environments in maxillofacial surgery.

[Application of virtual reality in surgical treatment of complex head and neck carcinoma].

PubMed

Zhou, Y Q; Li, C; Shui, C Y; Cai, Y C; Sun, R H; Zeng, D F; Wang, W; Li, Q L; Huang, L; Tu, J; Jiang, J

2018-01-07

Objective: To investigate the application of virtual reality technology in the preoperative evaluation of complex head and neck carcinoma and he value of virtual reality technology in surgical treatment of head and neck carcinoma. Methods: The image data of eight patients with complex head and neck carcinoma treated from December 2016 to May 2017 was acquired. The data were put into virtual reality system to built the three-dimensional anatomical model of carcinoma and to created the surgical scene. The process of surgery was stimulated by recognizing the relationship between tumor and surrounding important structures. Finally all patients were treated with surgery. And two typical cases were reported. Results: With the help of virtual reality, surgeons could adequately assess the condition of carcinoma and the security of operation and ensured the safety of operations. Conclusions: Virtual reality can provide the surgeons with the sensory experience in virtual surgery scenes and achieve the man-computer cooperation and stereoscopic assessment, which will ensure the safety of surgery. Virtual reality has a huge impact on guiding the traditional surgical procedure of head and neck carcinoma.

Active localization of virtual sounds

NASA Technical Reports Server (NTRS)

Loomis, Jack M.; Hebert, C.; Cicinelli, J. G.

1991-01-01

We describe a virtual sound display built around a 12 MHz 80286 microcomputer and special purpose analog hardware. The display implements most of the primary cues for sound localization in the ear-level plane. Static information about direction is conveyed by interaural time differences and, for frequencies above 1800 Hz, by head sound shadow (interaural intensity differences) and pinna sound shadow. Static information about distance is conveyed by variation in sound pressure (first power law) for all frequencies, by additional attenuation in the higher frequencies (simulating atmospheric absorption), and by the proportion of direct to reverberant sound. When the user actively locomotes, the changing angular position of the source occasioned by head rotations provides further information about direction and the changing angular velocity produced by head translations (motion parallax) provides further information about distance. Judging both from informal observations by users and from objective data obtained in an experiment on homing to virtual and real sounds, we conclude that simple displays such as this are effective in creating the perception of external sounds to which subjects can home with accuracy and ease.

Development of a nondestructive leak testing method utilizing the head space analyzer for ampoule products containing ethanol-based solutions.

PubMed

Sudo, Hirotaka; O'driscoll, Michael; Nishiwaki, Kenji; Kawamoto, Yuji; Gammell, Philip; Schramm, Gerhard; Wertli, Toni; Prinz, Heino; Mori, Atsuhide; Sako, Kazuhiro

2012-01-01

The application of a head space analyzer for oxygen concentration was examined to develop a novel ampoule leak test method. Studies using ampoules filled with ethanol-based solution and with nitrogen in the headspace demonstrated that the head space analysis (HSA) method showed sufficient sensitivity in detecting an ampoule crack. The proposed method is the use of HSA in conjunction with the pretreatment of an overpressurising process known as bombing to facilitate the oxygen flow through the crack in the ampoule. The method was examined in comparative studies with a conventional dye ingress method, and the results showed that the HSA method exhibits sensitivity superior to the dye method. The results indicate that the HSA method in combination with the bombing treatment provides potential application as a leak test for the detection of container defects not only for ampoule products with ethanol-based solutions, but also for testing lyophilized products in vials with nitrogen in the head space. The application of a head space analyzer for oxygen concentration was examined to develop a novel ampoule leak test method. The proposed method is the use of head space analysis (HSA) in conjunction with the pretreatment of an overpressurising process known as bombing to facilitate oxygen flow through the crack in the ampoule for use in routine production. The result of the comparative study with a conventional dye leak test method indicates that the HSA method in combination with the bombing treatment can be used as a leak test method, enabling detection of container defects.

V-Assembly Dual-Head Efficient Resonator (VADER) for Remote Sensing Applications

NASA Technical Reports Server (NTRS)

Coyle, D. Barry; Kay, Richard B.; Stysley, Paul R.; Clark, Greg; Poulios, Demetrios; Frederickson, Robert; Blalock, Gordon; Arnold, Ed; Cory, Ken

2011-01-01

The V-Assembly Dual-head Efficient Resonator (VADER) is a diode pumped, Nd:YAG, Q-switched, positive branch unstable resonator that employs a split laser gain module designed for optimal efficiency and thermal lensing compensation.

40 CFR 412.4 - Best management practices (BMPs) for land application of manure, litter, and process wastewater.

Code of Federal Regulations, 2012 CFR

2012-07-01

...: Open tile line intake structures, sinkholes, and agricultural well heads. (2) Vegetated buffer means a... surface waters, open tile line intake structures, sinkholes, agricultural well heads, or other conduits to...

40 CFR 412.4 - Best management practices (BMPs) for land application of manure, litter, and process wastewater.

Code of Federal Regulations, 2013 CFR

2013-07-01

...: Open tile line intake structures, sinkholes, and agricultural well heads. (2) Vegetated buffer means a... surface waters, open tile line intake structures, sinkholes, agricultural well heads, or other conduits to...

40 CFR 412.4 - Best management practices (BMPs) for land application of manure, litter, and process wastewater.

Code of Federal Regulations, 2014 CFR

2014-07-01

...: Open tile line intake structures, sinkholes, and agricultural well heads. (2) Vegetated buffer means a... surface waters, open tile line intake structures, sinkholes, agricultural well heads, or other conduits to...

49 CFR 571.202a - Standard No. 202a; Head restraints; Mandatory applicability begins on September 1, 2009.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., representing the head position of a seated 50th percentile male, with sliding scale at the back of the head for... any rear outboard designated seating position, a rear seat back, or any independently adjustable seat component attached to or adjacent to a seat back, that has a height equal to or greater than 700 mm, in any...

49 CFR 571.202a - Standard No. 202a; Head restraints; Mandatory applicability begins on September 1, 2009.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., representing the head position of a seated 50th percentile male, with sliding scale at the back of the head for... any rear outboard designated seating position, a rear seat back, or any independently adjustable seat component attached to or adjacent to a seat back, that has a height equal to or greater than 700 mm, in any...

49 CFR 571.202a - Standard No. 202a; Head restraints; Mandatory applicability begins on September 1, 2009.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., representing the head position of a seated 50th percentile male, with sliding scale at the back of the head for... any rear outboard designated seating position, a rear seat back, or any independently adjustable seat component attached to or adjacent to a seat back, that has a height equal to or greater than 700 mm, in any...

ICF Core Set for Head and Neck Cancer: Do the Categories Discriminate Among Clinically Relevant Subgroups of Patients?

ERIC Educational Resources Information Center

Tschiesner, Uta; Oberhauser, Cornelia; Cieza, Alarcos

2011-01-01

The multidisciplinary assessment of functioning in patients with head and neck cancer (HNC) according to the "ICF Core Set for Head and Neck Cancer" (ICF-HNC) was developed in an international and multi-disciplinary approach. The ICF-HNC is an application of the ICF that was adopted by the World Health Organization. The objective of this study was…

Head movement compensation in real-time magnetoencephalographic recordings.

PubMed

Little, Graham; Boe, Shaun; Bardouille, Timothy

2014-01-01

Neurofeedback- and brain-computer interface (BCI)-based interventions can be implemented using real-time analysis of magnetoencephalographic (MEG) recordings. Head movement during MEG recordings, however, can lead to inaccurate estimates of brain activity, reducing the efficacy of the intervention. Most real-time applications in MEG have utilized analyses that do not correct for head movement. Effective means of correcting for head movement are needed to optimize the use of MEG in such applications. Here we provide preliminary validation of a novel analysis technique, real-time source estimation (rtSE), that measures head movement and generates corrected current source time course estimates in real-time. rtSE was applied while recording a calibrated phantom to determine phantom position localization accuracy and source amplitude estimation accuracy under stationary and moving conditions. Results were compared to off-line analysis methods to assess validity of the rtSE technique. The rtSE method allowed for accurate estimation of current source activity at the source-level in real-time, and accounted for movement of the source due to changes in phantom position. The rtSE technique requires modifications and specialized analysis of the following MEG work flow steps.•Data acquisition•Head position estimation•Source localization•Real-time source estimation This work explains the technical details and validates each of these steps.

Head lice in progress: what could/should be done-a report on an in vivo and in vitro field study.

PubMed

Abdel-Ghaffar, Fathy; Abdel-Aty, Mohammed; Rizk, Ibrahim; Al-Quraishy, Saleh; Semmler, Margit; Gestmann, Falk; Hoff, Norman-Philipp

2016-11-01

Head lice infections are a growing problem in the light of increasing migration of large population as well as the increasing current refugee flows and concomitant poor hygienic conditions. These infections are associated with a significantly reduced quality of life and frequent medical consultations. The approved drugs for the treatment of head lice infections have some disadvantages in the treatment despite their good efficacy. In addition to irritant-toxic substances that can cause adverse reactions in patients, a partial development of resistance has occurred and a double application is necessary to achieve adequate efficacy. For this reason, we have decided to test a product without the aforementioned treatment drawbacks. We examined the effect of Licener® on the head lice treatment through individual therapy trials. We identified 65 patients with head lice infections for the treatment with Licener®. All patients were treated with Licener® and visited for a period of 2 weeks. Successfully treated patients had no relapses. Against the background of this study and based on the observations of our applications, we expect that Licener® could enhance considerably the therapeutic options for the treatment of head lice infections, as an alternative to classical products.

3D Perception Technologies for Surgical Operating Theatres.

PubMed

Beyl, T; Schreiter, L; Nicolai, P; Raczkowsky, J; Wörn, H

2016-01-01

3D Perception technologies have been explored in various fields. This paper explores the application of such technologies for surgical operating theatres. Clinical applications can be found in workflow detection, tracking and analysis, collision avoidance with medical robots, perception of interaction between participants of the operation, training of the operation room crew, patient calibration and many more. In this paper a complete perception solution for the operating room is shown. The system is based on the ToF technology integrated to the Microsoft Kinect One implements a multi camera approach. Special emphasize is put on the tracking of the personnel and the evaluation of the system performance and accuracy.

A cross-circulated bicephalic model of head transplantation.

PubMed

Li, Peng-Wei; Zhao, Xin; Zhao, Yun-Long; Wang, Bing-Jian; Song, Yang; Shen, Zi-Long; Jiang, Hong-Jun; Jin, Hai; Canavero, Sergio; Ren, Xiao-Ping

2017-06-01

A successful cephalosomatic anastomosis ("head transplant") requires, among others, the ability to control long-term immune rejection and avoidance of ischemic events during the head transference phase. We developed a bicephalic model of head transplantation to study these aspects. The thoracic aorta and superior vena cava of a donor rat were anastomosed with the carotid artery and extracorporeal veins of a recipient rat by vascular grafts. Before thoracotomy in the donor rat, the axillary artery and vein of the donor were connected to the carotid and the extracranial vein of the third rat through a silicone tube. The silicone tube was passed through a peristaltic pump to ensure donor brain tissue blood supply. There is no ischemia reperfusion injury in donor brain tissue analyzed by electroencephalogram. Postoperative donor has pain reflex and corneal reflex. Peristaltic pump application can guarantee the blood supply of donor brain tissue per unit time, while the application of temperature change device to the silicone tube can protect the brain tissue hypothermia, postoperative experimental data show that there is no brain tissue ischemia during the whole operation. The application of vascular grafting can also provide the possibility of long-term survival of the model. © 2017 John Wiley & Sons Ltd.

Ventral and dorsal streams processing visual motion perception (FDG-PET study)

PubMed Central

2012-01-01

Background Earlier functional imaging studies on visually induced self-motion perception (vection) disclosed a bilateral network of activations within primary and secondary visual cortex areas which was combined with signal decreases, i.e., deactivations, in multisensory vestibular cortex areas. This finding led to the concept of a reciprocal inhibitory interaction between the visual and vestibular systems. In order to define areas involved in special aspects of self-motion perception such as intensity and duration of the perceived circular vection (CV) or the amount of head tilt, correlation analyses of the regional cerebral glucose metabolism, rCGM (measured by fluorodeoxyglucose positron-emission tomography, FDG-PET) and these perceptual covariates were performed in 14 healthy volunteers. For analyses of the visual-vestibular interaction, the CV data were compared to a random dot motion stimulation condition (not inducing vection) and a control group at rest (no stimulation at all). Results Group subtraction analyses showed that the visual-vestibular interaction was modified during CV, i.e., the activations within the cerebellar vermis and parieto-occipital areas were enhanced. The correlation analysis between the rCGM and the intensity of visually induced vection, experienced as body tilt, showed a relationship for areas of the multisensory vestibular cortical network (inferior parietal lobule bilaterally, anterior cingulate gyrus), the medial parieto-occipital cortex, the frontal eye fields and the cerebellar vermis. The “earlier” multisensory vestibular areas like the parieto-insular vestibular cortex and the superior temporal gyrus did not appear in the latter analysis. The duration of perceived vection after stimulus stop was positively correlated with rCGM in medial temporal lobe areas bilaterally, which included the (para-)hippocampus, known to be involved in various aspects of memory processing. The amount of head tilt was found to be positively correlated with the rCGM of bilateral basal ganglia regions responsible for the control of motor function of the head. Conclusions Our data gave further insights into subfunctions within the complex cortical network involved in the processing of visual-vestibular interaction during CV. Specific areas of this cortical network could be attributed to the ventral stream (“what” pathway) responsible for the duration after stimulus stop and to the dorsal stream (“where/how” pathway) responsible for intensity aspects. PMID:22800430

Vacuum compatible miniature CCD camera head

DOEpatents

Conder, Alan D.

2000-01-01

A charge-coupled device (CCD) camera head which can replace film for digital imaging of visible light, ultraviolet radiation, and soft to penetrating x-rays, such as within a target chamber where laser produced plasmas are studied. The camera head is small, capable of operating both in and out of a vacuum environment, and is versatile. The CCD camera head uses PC boards with an internal heat sink connected to the chassis for heat dissipation, which allows for close(0.04" for example) stacking of the PC boards. Integration of this CCD camera head into existing instrumentation provides a substantial enhancement of diagnostic capabilities for studying high energy density plasmas, for a variety of military industrial, and medical imaging applications.

Induction Heating Systems

NASA Technical Reports Server (NTRS)

1991-01-01

Induction heating technology, a magnetic non-deforming process, was developed by Langley researchers to join plastic and composite components in space. Under NASA license, Inductron Corporation uses the process to produce induction heating systems and equipment for numerous applications. The Torobonder, a portable system, comes with a number of interchangeable heads for aircraft repair. Other developments are the E Heating Head, the Toroid Joining Gun, and the Torobrazer. These products perform bonding applications more quickly, safely and efficiently than previous methods.

An Aloe Vera-Based Cosmeceutical Cream Delays and Mitigates Ionizing Radiation-Induced Dermatitis in Head and Neck Cancer Patients Undergoing Curative Radiotherapy: A Clinical Study.

PubMed

Rao, Suresh; Hegde, Sanath Kumar; Baliga-Rao, Manjeshwar Poonam; Palatty, Princy Louis; George, Thomas; Baliga, Manjeshwar Shrinath

2017-06-24

Background: This study was planned to evaluate the efficacy of topical application of an Aloe vera -based cream (AVC) for the prevention of ionizing radiation (X ray)-induced dermatitis in head and neck cancer patients requiring therapeutic radiation treatment (>62 Gy). Methods: From July 2012 to December 2012, a total of 60 head and neck cancer patients requiring curative radiotherapy (RT) of more than 66 Gy were prospectively enrolled and treated with AVC or a comparator Johnson's Baby Oil (JBO). Acute skin reaction was monitored and classified according to the Radiation Therapy Oncology Group (RTOG) four-point rating scale on a weekly basis. Results: The results indicate that there was a statistically significant delay in the incidence ( p = 0.04) of dermatitis at week three in the AVC application group. Application of AVC reduced the incidence of Grade 1, 2, and 3 dermatitis at subsequent time points, while Grade 4 dermatitis was not seen in either cohort. The other most important observation was that the continued application of AVC two weeks after the completion of RT was effective in reducing the average grade of dermatitis and was statistically significant ( p < 0.02). Conclusions : Prophylactic use of an AVC-based cream is thus effective in delaying radiation dermatitis in head and neck cancer.

An Aloe Vera-Based Cosmeceutical Cream Delays and Mitigates Ionizing Radiation-Induced Dermatitis in Head and Neck Cancer Patients Undergoing Curative Radiotherapy: A Clinical Study

PubMed Central

Rao, Suresh; Hegde, Sanath Kumar; Baliga-Rao, Manjeshwar Poonam; Palatty, Princy Louis; George, Thomas; Baliga, Manjeshwar Shrinath

2017-01-01

Background: This study was planned to evaluate the efficacy of topical application of an Aloe vera-based cream (AVC) for the prevention of ionizing radiation (X ray)-induced dermatitis in head and neck cancer patients requiring therapeutic radiation treatment (>62 Gy). Methods: From July 2012 to December 2012, a total of 60 head and neck cancer patients requiring curative radiotherapy (RT) of more than 66 Gy were prospectively enrolled and treated with AVC or a comparator Johnson’s Baby Oil (JBO). Acute skin reaction was monitored and classified according to the Radiation Therapy Oncology Group (RTOG) four-point rating scale on a weekly basis. Results: The results indicate that there was a statistically significant delay in the incidence (p = 0.04) of dermatitis at week three in the AVC application group. Application of AVC reduced the incidence of Grade 1, 2, and 3 dermatitis at subsequent time points, while Grade 4 dermatitis was not seen in either cohort. The other most important observation was that the continued application of AVC two weeks after the completion of RT was effective in reducing the average grade of dermatitis and was statistically significant (p < 0.02). Conclusions: Prophylactic use of an AVC-based cream is thus effective in delaying radiation dermatitis in head and neck cancer. PMID:28930258

Numerical model (switchable/dual model) of the human head for rigid body and finite elements applications.

PubMed

Tabacu, Stefan

2015-01-01

In this paper, a methodology for the development and validation of a numerical model of the human head using generic procedures is presented. All steps required, starting with the model generation, model validation and applications will be discussed. The proposed model may be considered as a dual one due to its capabilities to switch from deformable to a rigid body according to the application's requirements. The first step is to generate the numerical model of the human head using geometry files or medical images. The required stiffness and damping for the elastic connection used for the rigid body model are identified by performing a natural frequency analysis. The presented applications for model validation are related to impact analysis. The first case is related to Nahum's (Nahum and Smith 1970) experiments pressure data being evaluated and a pressure map generated using the results from discrete elements. For the second case, the relative displacement between the brain and the skull is evaluated according to Hardy's (Hardy WH, Foster CD, Mason, MJ, Yang KH, King A, Tashman S. 2001.Investigation of head injury mechanisms using neutral density technology and high-speed biplanar X-ray. Stapp Car Crash J. 45:337-368, SAE Paper 2001-22-0016) experiments. The main objective is to validate the rigid model as a quick and versatile tool for acquiring the input data for specific brain analyses.

Targeting red-headed flea beetle larvae

USDA-ARS?s Scientific Manuscript database

Red-headed flea beetle (RHFB), Systena frontalis, is an emerging pest of cranberry that requires significant grower investment in monitoring and repeated applications of insecticides to reduce adult populations. The adult beetles are highly mobile and consume a broad range of host plants whereas t...

The 14th Annual Conference on Manual Control. [digital simulation of human operator dynamics

NASA Technical Reports Server (NTRS)

1978-01-01

Human operator dynamics during actual manual control or while monitoring the automatic control systems involved in air-to-air tracking, automobile driving, the operator of undersea vehicles, and remote handling are examined. Optimal control models and the use of mathematical theory in representing man behavior in complex man machine system tasks are discussed with emphasis on eye/head tracking and scanning; perception and attention allocation; decision making; and motion simulation and effects.

Perception of the dynamic visual vertical during sinusoidal linear motion.

PubMed

Pomante, A; Selen, L P J; Medendorp, W P

2017-10-01

The vestibular system provides information for spatial orientation. However, this information is ambiguous: because the otoliths sense the gravitoinertial force, they cannot distinguish gravitational and inertial components. As a consequence, prolonged linear acceleration of the head can be interpreted as tilt, referred to as the somatogravic effect. Previous modeling work suggests that the brain disambiguates the otolith signal according to the rules of Bayesian inference, combining noisy canal cues with the a priori assumption that prolonged linear accelerations are unlikely. Within this modeling framework the noise of the vestibular signals affects the dynamic characteristics of the tilt percept during linear whole-body motion. To test this prediction, we devised a novel paradigm to psychometrically characterize the dynamic visual vertical-as a proxy for the tilt percept-during passive sinusoidal linear motion along the interaural axis (0.33 Hz motion frequency, 1.75 m/s 2 peak acceleration, 80 cm displacement). While subjects ( n =10) kept fixation on a central body-fixed light, a line was briefly flashed (5 ms) at different phases of the motion, the orientation of which had to be judged relative to gravity. Consistent with the model's prediction, subjects showed a phase-dependent modulation of the dynamic visual vertical, with a subject-specific phase shift with respect to the imposed acceleration signal. The magnitude of this modulation was smaller than predicted, suggesting a contribution of nonvestibular signals to the dynamic visual vertical. Despite their dampening effect, our findings may point to a link between the noise components in the vestibular system and the characteristics of dynamic visual vertical. NEW & NOTEWORTHY A fundamental question in neuroscience is how the brain processes vestibular signals to infer the orientation of the body and objects in space. We show that, under sinusoidal linear motion, systematic error patterns appear in the disambiguation of linear acceleration and spatial orientation. We discuss the dynamics of these illusory percepts in terms of a dynamic Bayesian model that combines uncertainty in the vestibular signals with priors based on the natural statistics of head motion. Copyright © 2017 the American Physiological Society.

M.I.T./Canadian vestibular experiments on the Spacelab-1 mission: 6. Vestibular reactions to lateral acceleration following ten days of weightlessness

NASA Technical Reports Server (NTRS)

Arrott, A. P.; Young, L. R.

1986-01-01

Tests of otolith function were performed pre-flight and post-flight on the science crew of the first Spacelab Mission with a rail-mounted linear acceleration sled. Four tests were performed using horizontal lateral (y-axis) acceleration: perception of linear motion, a closed loop nulling task, dynamic ocular torsion, and lateral eye deviations. The motion perception test measured the time to detect the onset and direction of near threshold accelerations. Post-flight measures of threshold and velocity constant obtained during the days immediately following the mission showed no consistent pattern of change among the four crewmen compared to their pre-flight baseline other than an increased variability of response. In the closed loop nulling task, crewmen controlled the motion of the sled and attempted to null a computer-generated random disturbance motion. When performed in the light, no difference in ability was noted between pre-flight and post-flight. In the dark, however, two of the four crewmen exhibited somewhat enhanced performance post-flight. Dynamic ocular torsion was measured in response to sinusoidal lateral acceleration which produces a gravitionertial stimulus equivalent to lateral head tilt without rotational movement of the head. Results available for two crewmen suggest a decreased amplitude of sinusoidal ocular torsion when measured on the day of landing (R+0) and an increasing amplitude when measured during the week following the mission.

Psychomotor performance during a 28 day head-down tilt with and without lower body negative pressure

NASA Astrophysics Data System (ADS)

Traon, A. Pavy-le; de Feneyrols, A. Rous; Cornac, A.; Abdeseelam, R.; N'uygen, D.; Lazerges, M.; Güell, A.; Bes, A.

Several factors may affect psychomotor performance in space: sensory-motor changes, sleep disturbances, psychological modifications induced by the social isolation and confinement. However, psychomotor performance is difficult to assess. A battery of standardized and computerized tests, so-called "Automated Portable Test System" (APTS) was devised to ascertain the cognitive, perceptive and motor abilities and their possible fluctuations according to environmental effects. Antiorthostatic bedrest, often used to simulate weightlessness, (particularly cardiovascular modifications) also constitutes a situation of social confinement and isolation. During two bedrest experiments (with head-down tilt of -6°) of 28 days each, we intended to assess psychomotor performance of 6 males so as to determine whether: —on the one hand, it could be altered by remaining in decubitus; —on the other, the Lower Body Negative Pressure sessions, designed to prevent orthostatic intolerance back on Earth, could improve the performance. To accomplish this, part of the APTS tests as well as an automated perceptive attention test were performed. No downgrading of psychomotor performance was observed. On the contrary, the tasks were more accurately performed over time. In order to assess the experimental conditions on the acquisition phase, the learning curves were modelled. A beneficial effect of the LBNP sessions on simple tests involving the visual-motor coordination and attention faculties can only be regarded as a mere trend. Methods used in this experiment are also discussed.

User Design and Experience Preferences in a Novel Smartphone Application for Migraine Management: A Think Aloud Study of the RELAXaHEAD Application.

PubMed

Minen, Mia T; Jalloh, Adama; Ortega, Emma; Powers, Scott W; Sevick, Mary Ann; Lipton, Richard B

2018-05-30

Scalable nonpharmacologic treatment options are needed for chronic pain conditions. Migraine is an ideal condition to test smartphone-based mind-body interventions (MBIs) because it is a very prevalent, costly, disabling condition. Progressive muscle relaxation (PMR) is a standardized, evidence-based MBI previously adapted for smartphone applications for other conditions. We sought to examine the usability of the RELAXaHEAD application (app), which has a headache diary and PMR capability. Using the "Think Aloud" approach, we iteratively beta-tested RELAXaHEAD in people with migraine. Individual interviews were conducted, audio-recorded, and transcribed. Using Grounded Theory, we conducted thematic analysis. Participants also were asked Likert scale questions about satisfaction with the app and the PMR. Twelve subjects participated in the study. The mean duration of the interviews (SD, range) was 36 (11, 19-53) minutes. From the interviews, four main themes emerged. People were most interested in app utility/practicality, user interface, app functionality, and the potential utility of the PMR. Participants reported that the daily diary was easy to use (75%), was relevant for tracking headaches (75%), maintained their interest and attention (75%), and was easy to understand (83%). Ninety-two percent of the participants would be happy to use the app again. Participants reported that PMR maintained their interest and attention (75%) and improved their stress and low mood (75%). The RELAXaHEAD app may be acceptable and useful to migraine participants. Future studies will examine the use of the RELAXaHEAD app to deliver PMR to people with migraine in a low-cost, scalable manner.

A MATLAB-based eye tracking control system using non-invasive helmet head restraint in the macaque.

PubMed

De Luna, Paolo; Mohamed Mustafar, Mohamed Faiz Bin; Rainer, Gregor

2014-09-30

Tracking eye position is vital for behavioral and neurophysiological investigations in systems and cognitive neuroscience. Infrared camera systems which are now available can be used for eye tracking without the need to surgically implant magnetic search coils. These systems are generally employed using rigid head fixation in monkeys, which maintains the eye in a constant position and facilitates eye tracking. We investigate the use of non-rigid head fixation using a helmet that constrains only general head orientation and allows some freedom of movement. We present a MATLAB software solution to gather and process eye position data, present visual stimuli, interact with various devices, provide experimenter feedback and store data for offline analysis. Our software solution achieves excellent timing performance due to the use of data streaming, instead of the traditionally employed data storage mode for processing analog eye position data. We present behavioral data from two monkeys, demonstrating that adequate performance levels can be achieved on a simple fixation paradigm and show how performance depends on parameters such as fixation window size. Our findings suggest that non-rigid head restraint can be employed for behavioral training and testing on a variety of gaze-dependent visual paradigms, reducing the need for rigid head restraint systems for some applications. While developed for macaque monkey, our system of course can work equally well for applications in human eye tracking where head constraint is undesirable. Copyright © 2014. Published by Elsevier B.V.

Interactive navigation system for shock wave applications.

PubMed

Hagelauer, U; Russo, S; Gigliotti, S; de Durante, C; Corrado, E M

2001-01-01

The latest generation of shock wave lithotripters, with therapy heads mounted on articulated arms, have found widespread application in the treatment of orthopedic diseases. Currently, integration of an ultrasound probe in the therapy head is the dominant modality for positioning the shock wave focus on the treatment area. For orthopedic applications, however, X-ray imaging is often preferred. This article describes a new method to locate the therapy head of a lithotripter. In the first step, the surgeon positions the tissue to be treated at the isocenter of a C-arc. This is achieved using AP and 30-degree lateral projections, with corresponding horizontal and vertical movements of the patient under fluoroscopic guidance. These movements register the anatomic location in the coordinate system of the C-arc. In the second step, the therapy head is navigated to align the shock wave focus with the isocenter. Position data are reported from an optical tracker mounted on the X-ray system, which tracks an array of infrared LEDs on the therapy head. The accuracy of the tracking system was determined on a test bench, and was calculated to be 1.55 mm (RMS) for an angular movement of +/-15 degrees around a calibrated position. Free-hand navigation and precise alignment are performed with a single virtual reality display. The display is calculated by a computer system in real time, and uses graphical symbols to represent the shock wave path and isocenter. In an interactive process, the physician observes the display while navigating the therapy head towards the isocenter. Precise alignment is achieved by displaying an enlarged view of the intersecting graphical symbols. Results from the first tests on 100 patients demonstrate the feasibility of this approach in a clinical environment. Copyright 2001 Wiley-Liss, Inc.

Missing depth cues in virtual reality limit performance and quality of three dimensional reaching movements

PubMed Central

Mayo, Johnathan; Baur, Kilian; Wittmann, Frieder; Riener, Robert; Wolf, Peter

2018-01-01

Background Goal-directed reaching for real-world objects by humans is enabled through visual depth cues. In virtual environments, the number and quality of available visual depth cues is limited, which may affect reaching performance and quality of reaching movements. Methods We assessed three-dimensional reaching movements in five experimental groups each with ten healthy volunteers. Three groups used a two-dimensional computer screen and two groups used a head-mounted display. The first screen group received the typically recreated visual depth cues, such as aerial and linear perspective, occlusion, shadows, and texture gradients. The second screen group received an abstract minimal rendering lacking those. The third screen group received the cues of the first screen group and absolute depth cues enabled by retinal image size of a known object, which realized with visual renderings of the handheld device and a ghost handheld at the target location. The two head-mounted display groups received the same virtually recreated visual depth cues as the second or the third screen group respectively. Additionally, they could rely on stereopsis and motion parallax due to head-movements. Results and conclusion All groups using the screen performed significantly worse than both groups using the head-mounted display in terms of completion time normalized by the straight-line distance to the target. Both groups using the head-mounted display achieved the optimal minimum in number of speed peaks and in hand path ratio, indicating that our subjects performed natural movements when using a head-mounted display. Virtually recreated visual depth cues had a minor impact on reaching performance. Only the screen group with rendered handhelds could outperform the other screen groups. Thus, if reaching performance in virtual environments is in the main scope of a study, we suggest applying a head-mounted display. Otherwise, when two-dimensional screens are used, achievable performance is likely limited by the reduced depth perception and not just by subjects’ motor skills. PMID:29293512

The art of perception: Patients drawing their vestibular schwannoma.

PubMed

van Leeuwen, Bibian M; Herruer, Jasmijn M; Putter, Hein; van der Mey, Andel G L; Kaptein, Adrian A

2015-12-01

Drawings made by patients are an innovative way to assess the perceptions of patients on their illness. The objective of this study, at a university tertiary referral center, on patients who have recently been diagnosed with vestibular schwannoma, was to examine whether patients' illness perceptions can be assessed by drawings and are related to their quality of life. Cross-sectional study. Patients diagnosed with vestibular schwannoma (mean age [range], 55.4 [17-85] years) between April 2011 and October 2012 were included (N = 253). Sociodemographics, illness perceptions (Brief Illness Perception Questionnaire [B-IPQ]), and disease-specific quality of life (Penn Acoustic Neuroma Quality of Life [PANQOL] scale) were assessed to evaluate the impact of being diagnosed with vestibular schwannoma. Furthermore, patients' drawings of their tumor were analyzed to explore the association between illness perceptions, drawings, and quality of life. Comparison of the B-IPQ scores of the current sample (N = 139; response rate 54.9%) with other disease samples shows a significantly lower score for patients with vestibular schwannoma on the Coherence dimension, indicating a low understanding of the illness. Illustration of emotions (N = 12) in the drawings gave a negative association with quality of life. Intercorrelations indicate a positive association between a low amount of physical and emotional consequences of the illness and a higher score on the Balance, Hearing, and Energy dimensions of the PANQOL. Patients' drawings give an insight into their perception of the tumor inside their head. Use of drawings may be helpful when developing and offering self-management programs. Quality of life appears to be significantly affected by the diagnosis. 4. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Time management behaviors of head nurses and staff nurses employed in Tehran Social Security Hospitals, Iran in 2011.

PubMed

Ebrahimi, Hossein; Hosseinzadeh, Rahele; Tefreshi, Mansoreh Zaghari; Hosseinzadeh, Sadaf

2014-03-01

Effective time management is considered important for managers for achieving the goals in an organization. Head nurses can improve their efficiency and performance with effective use of time. There has always been a lot of disagreement in understanding time management behaviors of head nurses; therefore, the present study was conducted with an aim to compare the understanding of head nurses and staff nurses of the time management behaviors of head nurses employed in Social Security Hospitals in Tehran, Iran in 2011. This was a comparative descriptive study in which 85 head nurses were selected through census and 170 staff nurses were also selected through simple random sampling method from hospitals covered by the Social Security. Data collection was done through a standard inventory with high validity and reliability, which consisted of two parts: Socio-demographic characteristics and time management inventory. The obtained data were analyzed by descriptive and inferential statistics through SPSS software version 13. Mean score of time management in head nurses' viewpoint was 143.22 (±18.66) and in staff nurses' viewpoint was 136.04 (±21.45). There was a significant correlation between the mean scores of head nurses' time management and some of their socio-demographic characteristics such as gender, clinical experience, passing a time management course, and book reading (P < 0.05). There was a significant correlation between the mean scores of staff nurses' time management and their clinical working experience, education, using time management approach, and type of hospital (P < 0.05). The majority of head nurses (52.9%) believed that their time management was in a high level; besides, most of the staff nurses also (40%) believed that time management of their head nurses was high. However, there was a significant difference between the perceptions of both groups on using Mann-Whitney test (P < 0.05). With regard to the importance of time management and its vital role in the quality of nursing care for clients, and also the fact that head nurses believed more in their time management behaviors, they are expected to improve organization's goals and developments in order to modify the weaknesses and shortages and promote the skills and capabilities of their staffs and also resolve the disagreement on the understanding of time management. Moreover, effective time management training programs can be an important step for staff nurses and their head nurses.

Time management behaviors of head nurses and staff nurses employed in Tehran Social Security Hospitals, Iran in 2011

PubMed Central

Ebrahimi, Hossein; Hosseinzadeh, Rahele; Tefreshi, Mansoreh Zaghari; Hosseinzadeh, Sadaf

2014-01-01

Background: Effective time management is considered important for managers for achieving the goals in an organization. Head nurses can improve their efficiency and performance with effective use of time. There has always been a lot of disagreement in understanding time management behaviors of head nurses; therefore, the present study was conducted with an aim to compare the understanding of head nurses and staff nurses of the time management behaviors of head nurses employed in Social Security Hospitals in Tehran, Iran in 2011. Materials and Methods: This was a comparative descriptive study in which 85 head nurses were selected through census and 170 staff nurses were also selected through simple random sampling method from hospitals covered by the Social Security. Data collection was done through a standard inventory with high validity and reliability, which consisted of two parts: Socio-demographic characteristics and time management inventory. The obtained data were analyzed by descriptive and inferential statistics through SPSS software version 13. Results: Mean score of time management in head nurses’ viewpoint was 143.22 (±18.66) and in staff nurses’ viewpoint was 136.04 (±21.45). There was a significant correlation between the mean scores of head nurses’ time management and some of their socio-demographic characteristics such as gender, clinical experience, passing a time management course, and book reading (P < 0.05). There was a significant correlation between the mean scores of staff nurses’ time management and their clinical working experience, education, using time management approach, and type of hospital (P < 0.05). The majority of head nurses (52.9%) believed that their time management was in a high level; besides, most of the staff nurses also (40%) believed that time management of their head nurses was high. However, there was a significant difference between the perceptions of both groups on using Mann–Whitney test (P < 0.05). Conclusion: With regard to the importance of time management and its vital role in the quality of nursing care for clients, and also the fact that head nurses believed more in their time management behaviors, they are expected to improve organization's goals and developments in order to modify the weaknesses and shortages and promote the skills and capabilities of their staffs and also resolve the disagreement on the understanding of time management. Moreover, effective time management training programs can be an important step for staff nurses and their head nurses. PMID:24834090

Communicating headings and preview sentences in text and speech.

PubMed

Lorch, Robert F; Chen, Hung-Tao; Lemarié, Julie

2012-09-01

Two experiments tested the effects of preview sentences and headings on the quality of college students' outlines of informational texts. Experiment 1 found that performance was much better in the preview sentences condition than in a no-signals condition for both printed text and text-to-speech (TTS) audio rendering of the printed text. In contrast, performance in the headings condition was good for the printed text but poor for the auditory presentation because the TTS software failed to communicate nonverbal information carried by the visual headings. Experiment 2 compared outlining performance for five headings conditions during TTS presentation. Using a theoretical framework, "signaling available, relevant, accessible" (SARA) information, to provide an analysis of the information content of headings in the printed text, the manipulation of the headings systematically restored information that was omitted by the TTS application in Experiment 1. The result was that outlining performance improved to levels similar to the visual headings condition of Experiment 1. It is argued that SARA is a useful framework for guiding future development of TTS software for a wide variety of text signaling devices, not just headings.

Evaluation of Long-Term Cochlear Implant Use in Subjects With Acquired Unilateral Profound Hearing Loss: Focus on Binaural Auditory Outcomes.

PubMed

Mertens, Griet; De Bodt, Marc; Van de Heyning, Paul

Cochlear implantation (CI) in subjects with unilateral profound sensorineural hearing loss was investigated. The authors of the present study demonstrated the binaural auditory outcomes in a 12- and 36-month prospective cohort outcome study. The present study aimed to do a long-term (LT) evaluation of the auditory outcomes in an analogous study group. LT evaluation was derived from 12 single-sided deaf (SSD) CI recipients and from 11 CI recipients with asymmetric hearing loss (AHL). A structured interview was conducted with each subjects. Speech perception in noise and sound localization were assessed in a CIOFF and in a CION condition. Four binaural effects were calculated: summation effect (S0N0), squelch effect (S0NCI), combined head shadow effect (SCIN0), and spatial release from masking (SRM). At the LT evaluation, the contribution of a CI or a bone conduction device on speech perception in noise was investigated in two challenging spatial configurations in the SSD group. All (23/23) subjects wore their CI 7 days a week at LT follow-up evaluation, which ranged from 3 to 10 years after implantation. In the SSD group, a significant combined head shadow effect of 3.17 dB and an SRM benefit of 4.33 dB were found. In the AHL group, on the other hand, the summation effect (2.00 dB), the squelch effect (2.67 dB), the combined head shadow effect (3.67 dB), and SRM benefit (2.00 dB) were significant at LT testing. In both the spatial challenging configurations, the speech in noise results was significantly worse in the condition with the bone conduction device compared with the unaided condition. No negative effect was found for the CION condition. A significant benefit in the CION condition was found for sound localization compared with the CIOFF condition in the SSD group and in the AHL group. All subjects wore their CI 7 days a week at LT follow-up evaluation. The presence of binaural effects has been demonstrated with speech in noise testing, sound localization, and subjective evaluation. In the AHL group, all investigated binaural effects were found to be significant. In the SSD group on the other hand, only SRM and the head shadow, the two most robust binaural effects, were significantly present. However, it took 12M before the SSD and the AHL subjects significantly benefit from the head shadow effect. These reported results could guide counseling of future CI candidates with SSD and AHL in general.

Combat vehicle crew helmet-mounted display: next generation high-resolution head-mounted display

NASA Astrophysics Data System (ADS)

Nelson, Scott A.

1994-06-01

The Combat Vehicle Crew Head-Mounted Display (CVC HMD) program is an ARPA-funded, US Army Natick Research, Development, and Engineering Center monitored effort to develop a high resolution, flat panel HMD for the M1 A2 Abrams main battle tank. CVC HMD is part of the ARPA High Definition Systems (HDS) thrust to develop and integrate small (24 micrometers square pels), high resolution (1280 X 1024 X 6-bit grey scale at 60 frame/sec) active matrix electroluminescent (AMEL) and active matrix liquid crystal displays (AMLCD) for head mounted and projection applications. The Honeywell designed CVC HMD is a next generation head-mounted display system that includes advanced flat panel image sources, advanced digital display driver electronics, high speed (> 1 Gbps) digital interconnect electronics, and light weight, high performance optical and mechanical designs. The resulting dramatic improvements in size, weight, power, and cost have already led to program spin offs for both military and commercial applications.

Optimizing Cluster Heads for Energy Efficiency in Large-Scale Heterogeneous Wireless Sensor Networks

DOE PAGES

Gu, Yi; Wu, Qishi; Rao, Nageswara S. V.

2010-01-01

Many complex sensor network applications require deploying a large number of inexpensive and small sensors in a vast geographical region to achieve quality through quantity. Hierarchical clustering is generally considered as an efficient and scalable way to facilitate the management and operation of such large-scale networks and minimize the total energy consumption for prolonged lifetime. Judicious selection of cluster heads for data integration and communication is critical to the success of applications based on hierarchical sensor networks organized as layered clusters. We investigate the problem of selecting sensor nodes in a predeployed sensor network to be the cluster heads tomore » minimize the total energy needed for data gathering. We rigorously derive an analytical formula to optimize the number of cluster heads in sensor networks under uniform node distribution, and propose a Distance-based Crowdedness Clustering algorithm to determine the cluster heads in sensor networks under general node distribution. The results from an extensive set of experiments on a large number of simulated sensor networks illustrate the performance superiority of the proposed solution over the clustering schemes based on k -means algorithm.« less

"Head up and eyes out" advances in head mounted displays capabilities

NASA Astrophysics Data System (ADS)

Cameron, Alex

2013-06-01

There are a host of helmet and head mounted displays, flooding the market place with displays which provide what is essentially a mobile computer display. What sets aviators HMDs apart is that they provide the user with accurate conformal information embedded in the pilots real world view (see through display) where the information presented is intuitive and easy to use because it overlays the real world (mix of sensor imagery, symbolic information and synthetic imagery) and enables them to stay head up, eyes out, - improving their effectiveness, reducing workload and improving safety. Such systems are an enabling technology in the provision of enhanced Situation Awareness (SA) and reducing user workload in high intensity situations. Safety Is Key; so the addition of these HMD functions cannot detract from the aircrew protection functions of conventional aircrew helmets which also include life support and audio communications. These capabilities are finding much wider application in new types of compact man mounted audio/visual products enabled by the emergence of new families of micro displays, novel optical concepts and ultra-compact low power processing solutions. This papers attempts to capture the key drivers and needs for future head mounted systems for aviation applications.

Tilt and Translation Motion Perception during Off Vertical Axis Rotation

NASA Technical Reports Server (NTRS)

Wood, Scott J.; Reschke, Millard F.; Clement, Gilles

2006-01-01

The effect of stimulus frequency on tilt and translation motion perception was studied during constant velocity off-vertical axis rotation (OVAR), and compared to the effect of stimulus frequency on eye movements. Fourteen healthy subjects were rotated in darkness about their longitudinal axis 10deg and 20deg off-vertical at 0.125 Hz, and 20deg offvertical at 0.5 Hz. Oculomotor responses were recorded using videography, and perceived motion was evaluated using verbal reports and a joystick with four degrees of freedom (pitch and roll tilt, mediallateral and anteriorposterior translation). During the lower frequency OVAR, subjects reported the perception of progressing along the edge of a cone. During higher frequency OVAR, subjects reported the perception of progressing along the edge of an upright cylinder. The modulation of both tilt recorded from the joystick and ocular torsion significantly increased as the tilt angle increased from 10deg to 20deg at 0.125 Hz, and then decreased at 0.5 Hz. Both tilt perception and torsion slightly lagged head orientation at 0.125 Hz. The phase lag of torsion increased at 0.5 Hz, while the phase of tilt perception did not change as a function of frequency. The amplitude of both translation perception recorded from the joystick and horizontal eye movements was negligible at 0.125 Hz and increased as a function of stimulus frequency. While the phase lead of horizontal eye movements decreased at 0.5 Hz, the phase of translation perception did not vary with stimulus frequency and was similar to the phase of tilt perception during all conditions. During dynamic linear acceleration in the absence of other sensory input (canal, vision) a change in stimulus frequency alone elicits similar changes in the amplitude of both self motion perception and eye movements. However, in contrast to the eye movements, the phase of both perceived tilt and translation motion is not altered by stimulus frequency. We conclude that the neural processing to distinguish tilt and translation linear acceleration stimuli differs between eye movements and motion perception.

The new era of robotic neck surgery: The universal application of the retroauricular approach.

PubMed

Byeon, Hyung Kwon; Koh, Yoon Woo

2015-12-01

Recent advances in technology has triggered the introduction of surgical robotics in the field of head and neck surgery and changed the landscape indefinitely. The advent of transoral robotic surgery and robotic thyroidectomy techniques has urged the extended applications of the robot to other neck surgeries including remote access surgeries. Based on earlier reports and our surgical experiences, this review will discuss in detail various robotic head and neck surgeries via retroauricular approach. © 2015 Wiley Periodicals, Inc.

Differences in gaze anticipation for locomotion with and without vision

PubMed Central

Authié, Colas N.; Hilt, Pauline M.; N'Guyen, Steve; Berthoz, Alain; Bennequin, Daniel

2015-01-01

Previous experimental studies have shown a spontaneous anticipation of locomotor trajectory by the head and gaze direction during human locomotion. This anticipatory behavior could serve several functions: an optimal selection of visual information, for instance through landmarks and optic flow, as well as trajectory planning and motor control. This would imply that anticipation remains in darkness but with different characteristics. We asked 10 participants to walk along two predefined complex trajectories (limaçon and figure eight) without any cue on the trajectory to follow. Two visual conditions were used: (i) in light and (ii) in complete darkness with eyes open. The whole body kinematics were recorded by motion capture, along with the participant's right eye movements. We showed that in darkness and in light, horizontal gaze anticipates the orientation of the head which itself anticipates the trajectory direction. However, the horizontal angular anticipation decreases by a half in darkness for both gaze and head. In both visual conditions we observed an eye nystagmus with similar properties (frequency and amplitude). The main difference comes from the fact that in light, there is a shift of the orientations of the eye nystagmus and the head in the direction of the trajectory. These results suggest that a fundamental function of gaze is to represent self motion, stabilize the perception of space during locomotion, and to simulate the future trajectory, regardless of the vision condition. PMID:26106313

Where You Look Matters for Body Perception: Preferred Gaze Location Contributes to the Body Inversion Effect

PubMed Central

McKean, Danielle L.; Tsao, Jack W.; Chan, Annie W.-Y.

2017-01-01

The Body Inversion Effect (BIE; reduced visual discrimination performance for inverted compared to upright bodies) suggests that bodies are visually processed configurally; however, the specific importance of head posture information in the BIE has been indicated in reports of BIE reduction for whole bodies with fixed head position and for headless bodies. Through measurement of gaze patterns and investigation of the causal relation of fixation location to visual body discrimination performance, the present study reveals joint contributions of feature and configuration processing to visual body discrimination. Participants predominantly gazed at the (body-centric) upper body for upright bodies and the lower body for inverted bodies in the context of an experimental paradigm directly comparable to that of prior studies of the BIE. Subsequent manipulation of fixation location indicates that these preferential gaze locations causally contributed to the BIE for whole bodies largely due to the informative nature of gazing at or near the head. Also, a BIE was detected for both whole and headless bodies even when fixation location on the body was held constant, indicating a role of configural processing in body discrimination, though inclusion of the head posture information was still highly discriminative in the context of such processing. Interestingly, the impact of configuration (upright and inverted) to the BIE appears greater than that of differential preferred gaze locations. PMID:28085894

Enhanced Vertical Perception through Head-Related Impulse Response Customization Based on Pinna Response Tuning in the Median Plane

NASA Astrophysics Data System (ADS)

Shin, Ki Hoon; Park, Youngjin

Human's ability to perceive elevation of a sound and distinguish whether a sound is coming from the front or rear strongly depends on the monaural spectral features of the pinnae. In order to realize an effective virtual auditory display by HRTF (head-related transfer function) customization, the pinna responses were isolated from the median HRIRs (head-related impulse responses) of 45 individual HRIRs in the CIPIC HRTF database and modeled as linear combinations of 4 or 5 basic temporal shapes (basis functions) per each elevation on the median plane by PCA (principal components analysis) in the time domain. By tuning the weight of each basis function computed for a specific height to replace the pinna response in the KEMAR HRIR at the same height with the resulting customized pinna response and listening to the filtered stimuli over headphones, 4 individuals with normal hearing sensitivity were able to create a set of HRIRs that outperformed the KEMAR HRIRs in producing vertical effects with reduced front/back ambiguity in the median plane. Since the monaural spectral features of the pinnae are almost independent of azimuthal variation of the source direction, similar vertical effects could also be generated at different azimuthal directions simply by varying the ITD (interaural time difference) according to the direction as well as the size of each individual's own head.

The evaluation of the compatibility of electronic patient record (EPR) system with nurses' management needs in a developing country.

PubMed

Kahouei, Mehdi; Zadeh, Jamileh Mahdi; Roghani, Panoe Seyed

2015-04-01

In a developing country like Iran, wasting economic resources has a number of negative consequences. Therefore, it is crucial that problems of introducing new electronic systems be identified and addressed early to avoid failure of the programs. The purpose of this study was to evaluate head nurses' and supervisors' perceptions about the efficiency of the electronic patient record (EPR) system and its impact on nursing management tasks in order to provide useful recommendations. This descriptive study was performed in teaching hospitals affiliated to Semnan University of Medical Sciences, Iran. An anonymous self-administered questionnaire was developed. Head nurses and supervisors were included in this study. It was found that the EPR system was immature and was not proportionate to the operational level. Moreover, few head nurses and supervisors agreed on the benefits of the EPR system on the performance of their duties such as planning, organizing, budgeting, and coordinating. It is concluded that in addition to the technical improvements, the social and cultural factors should be considered to improve the acceptability of electronic systems through social marketing in the different aspects of nursing management. It is essential that health information technology managers emphasize on training head nurses and supervisors to design technology corresponding to their needs rather than to accept poorly designed technology. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Acute Appendicitis, Somatosensory Disturbances ("Head Zones"), and the Differential Diagnosis of Anterior Cutaneous Nerve Entrapment Syndrome (ACNES).

PubMed

Roumen, Rudi M H; Vening, Wouter; Wouda, Rosanne; Scheltinga, Marc M

2017-06-01

Anterior cutaneous nerve entrapment syndrome (ACNES) is a neuropathic abdominal wall pain syndrome typically characterized by locally altered skin sensations. On the other hand, visceral disease may also be associated with similar painful and altered skin sensations ("Head zones"). Aim of the study was to determine if patients with acute appendicitis demonstrated somatosensory disturbances in the corresponding right lower quadrant Head zone. The presence of somatosensory disturbances such as hyperalgesia, hypoesthesia, altered cool perception, or positive pinch test was determined in 100 patients before and after an appendectomy. Potential associations between altered skin sensations and various items including age, sex, history, body temperature, C-reactive protein (CRP), leukocyte count, and type of appendicopathy (normal, inflamed, necrotic, or perforated) were assessed. A total of 39 patients demonstrated at least one right lower abdominal quadrant skin somatosensory disturbance before the laparoscopic appendectomy. However, locoregional skin sensation normalized in all but 2 patients 2 weeks postoperatively. No differences were found concerning patient characteristics or type of appendicopathy between populations with or without altered lower abdominal skin sensations. A substantial portion of patients with acute appendicitis demonstrate right lower abdominal somatosensory disturbances that are similar as observed in acute ACNES. Both may be different sides of the same coin and are possibly expressions of segmental phenomena as described by Head. McBurney's point, a landmark area of maximum pain in acute appendicitis, is possibly a trigger point within a Head zone. Differentiating acute appendicitis from acute ACNES is extremely difficult, but imaging and observation may aid in the diagnostic process.

A novel device for head gesture measurement system in combination with eye-controlled human machine interface

NASA Astrophysics Data System (ADS)

Lin, Chern-Sheng; Ho, Chien-Wa; Chang, Kai-Chieh; Hung, San-Shan; Shei, Hung-Jung; Yeh, Mau-Shiun

2006-06-01

This study describes the design and combination of an eye-controlled and a head-controlled human-machine interface system. This system is a highly effective human-machine interface, detecting head movement by changing positions and numbers of light sources on the head. When the users utilize the head-mounted display to browse a computer screen, the system will catch the images of the user's eyes with CCD cameras, which can also measure the angle and position of the light sources. In the eye-tracking system, the program in the computer will locate each center point of the pupils in the images, and record the information on moving traces and pupil diameters. In the head gesture measurement system, the user wears a double-source eyeglass frame, so the system catches images of the user's head by using a CCD camera in front of the user. The computer program will locate the center point of the head, transferring it to the screen coordinates, and then the user can control the cursor by head motions. We combine the eye-controlled and head-controlled human-machine interface system for the virtual reality applications.

A review of head-worn display research at NASA Langley Research Center

NASA Astrophysics Data System (ADS)

Arthur, Jarvis J.; Bailey, Randall E.; Williams, Steven P.; Prinzel, Lawrence J.; Shelton, Kevin J.; Jones, Denise R.; Houston, Vincent

2015-05-01

NASA Langley has conducted research in the area of helmet-mounted/head-worn displays over the past 30 years. Initially, NASA Langley's research focused on military applications, but recently has conducted a line of research in the area of head-worn displays for commercial and business aircraft. This work has revolved around numerous simulation experiments as well as flight tests to develop technology and data for industry and regulatory guidance. The paper summarizes the results of NASA's helmet-mounted/head-worn display research. Of note, the work tracks progress in wearable collimated optics, head tracking, latency reduction, and weight. The research lends credence that a small, sunglasses-type form factor of the head-worn display would be acceptable to commercial pilots, and this goal is now becoming technologically feasible. The research further suggests that a head-worn display may serve as an "equivalent" Head-Up Display (HUD) with safety, operational, and cost benefits. "HUD equivalence" appears to be the economic avenue by which head-worn displays can become main-stream on the commercial and business aircraft flight deck. If this happens, NASA's research suggests that additional operational benefits using the unique capabilities of the head-worn display can open up new operational paradigms.

Printed circuit board for a CCD camera head

DOEpatents

Conder, Alan D.

2002-01-01

A charge-coupled device (CCD) camera head which can replace film for digital imaging of visible light, ultraviolet radiation, and soft to penetrating x-rays, such as within a target chamber where laser produced plasmas are studied. The camera head is small, capable of operating both in and out of a vacuum environment, and is versatile. The CCD camera head uses PC boards with an internal heat sink connected to the chassis for heat dissipation, which allows for close (0.04" for example) stacking of the PC boards. Integration of this CCD camera head into existing instrumentation provides a substantial enhancement of diagnostic capabilities for studying high energy density plasmas, for a variety of military industrial, and medical imaging applications.

The family receiving home care: functional health pattern assessment.

PubMed

Hooper, J I

1996-01-01

The winds of change in health care make assessment of the family more important than ever as a tool for health care providers seeking to assist the family move themselves toward high-level wellness. Limited medical care and imposed self-responsibility for health promotion and illness prevention, which are natural consequences of these changes, move the locus of control for health management back to the family. The family's teachings, modeling, and interactions are greater influences than ever on the health of the patient. Gordon's functional health patterns provide a holistic model for assessment of the family because assessment data are classified under 11 headings: health perception and health management, nutritional-metabolic, elimination, activity and exercise, sleep and rest, cognition and perception, self-perception and self-concept, roles and relationships, sexuality and reproduction, coping and stress tolerance, and values and beliefs. Questions posed under each of the health patterns can be varied to reflect the uniqueness of the individual family as well as to inquire about family strengths and weaknesses in all patterns. Data using this model provide a comprehensive base for including the family in designing a plan of care.

Factors affecting the perception of whole-body vibration of occupational drivers: an analysis of posture and manual materials handling and musculoskeletal disorders

PubMed Central

Raffler, Nastaran; Ellegast, Rolf; Kraus, Thomas; Ochsmann, Elke

2016-01-01

Due to the high cost of conducting field measurements, questionnaires are usually preferred for the assessment of physical workloads and musculoskeletal disorders (MSDs). This study compares the physical workloads of whole-body vibration (WBV) and awkward postures by direct field measurements and self-reported data of 45 occupational drivers. Manual materials handling (MMH) and MSDs were also investigated to analyse their effect on drivers' perception. Although the measured values for WBV exposure were very similarly distributed among the drivers, the subjects' perception differed significantly. Concerning posture, subjects seemed to estimate much better when the difference in exposure was significantly large. The percentage of measured awkward trunk and head inclination were significantly higher for WBV-overestimating subjects than non-overestimators; 77 and 80% vs. 36 and 33%. Health complaints in terms of thoracic spine, cervical spine and shoulder–arm were also significantly more reported by WBV-overestimating subjects (42, 67, 50% vs. 0, 25, 13%, respectively). Although more MMH was reported by WBV-overestimating subjects, there was no statistical significance in this study. PMID:26114619

Effects of Optical Combiner and IPD Change for Convergence on Near-Field Depth Perception in an Optical See-Through HMD.

PubMed

Lee, Sangyoon; Hu, Xinda; Hua, Hong

2016-05-01

Many error sources have been explored in regards to the depth perception problem in augmented reality environments using optical see-through head-mounted displays (OST-HMDs). Nonetheless, two error sources are commonly neglected: the ray-shift phenomenon and the change in interpupillary distance (IPD). The first source of error arises from the difference in refraction for virtual and see-through optical paths caused by an optical combiner, which is required of OST-HMDs. The second occurs from the change in the viewer's IPD due to eye convergence. In this paper, we analyze the effects of these two error sources on near-field depth perception and propose methods to compensate for these two types of errors. Furthermore, we investigate their effectiveness through an experiment comparing the conditions with and without our error compensation methods applied. In our experiment, participants estimated the egocentric depth of a virtual and a physical object located at seven different near-field distances (40∼200 cm) using a perceptual matching task. Although the experimental results showed different patterns depending on the target distance, the results demonstrated that the near-field depth perception error can be effectively reduced to a very small level (at most 1 percent error) by compensating for the two mentioned error sources.

Brain injury and discrimination: Two competing models-perceptions of responsibility and dangerousness.

PubMed

Foster, Lynette A; Leathem, Janet M; Humphries, Steve

2016-01-01

(1) To examine whether the willingness of people to socialize with adolescents with brain injury is influenced by gender, visibility of injury and/or knowing how to interact with people with brain injury; and (2) To consider two models: the responsibility model (attributions about the cause of a condition) and the danger appraisal model (perceptions of dangerousness due to anger/aggression) for their effect on willingness to socialize and to understand how these perceptions lead to avoidant behaviour. Participants were recruited either by personal approach or via Facebook advertising and completed a survey after reading a brief vignette and seeing a photo of an adolescent male or female, with or without a head scar. Vignettes for some participants were varied to represent perceptions of responsibility and dangerousness Main outcomes and results: ANOVAs and structural equation modelling revealed that participants were more willing to socialize with the adolescents with a scar than with no scar. Knowledge about how to interact with survivors impacted willingness to socialize, but familiarity did not. The full danger appraisal model was supported, but only some aspects of the responsibility model were supported. The results provide useful information for rehabilitation health professionals working with survivors of brain injury. The implications of these findings are discussed with regards to assisting adolescents' re-entry into society post-injury.

Attitude and perception of farmers to the implementation of conservation farming in the mountainous area of South Sulawesi

NASA Astrophysics Data System (ADS)

Busthanul, N.; Lumoindong, Y.; Syafiuddin, M.; Heliawaty; Lanuhu, N.; Ibrahim, T.; Ambrosius, R. R.

2018-05-01

Farmers’ attitudes and perceptions may be the cause of ineffective implementation of conservation farming for agriculture sustainability due to vary of implementing of conservation techniques. The purpose of this research is to know the attitude and perception of farmer toward the application of conservation technique and to know correlation between farmer attitude and perception toward the application of conservation technique. The research was carried out in Kanreapia Village, Tombolo Pao District, Gowa Regency, South Sulawesi Province, Indonesia. Sampling was done by randomly with 30 farmers; using non-parametric statistics with quantitative and qualitative descriptive data analysis approach, using Likert scale. The result showed that farmer attitude and perception toward conservation technique implementation which having the highest category (appropriate) is seasonal crop rotation, while the lowest with less appropriate category is the processing of land according to the contour and the cultivation of the plants accordingly. There is a very strong relationship between farmer attitude and perception. The implications of the findings are that improvements the implementation of conservation farming techniques should be made through improved perceptions.

Effects of prolonged weightlessness on self-motion perception and eye movements evoked by roll and pitch

NASA Technical Reports Server (NTRS)

Reschke, Millard F.; Parker, Donald E.

1987-01-01

Seven astronauts reported translational self-motion during roll simulation 1-3 h after landing following 5-7 d of orbital flight. Two reported strong translational self-motion perception when they performed pitch head motions during entry and while the orbiter was stationary on the runway. One of two astronauts from whom adequate data were collected exhibited a 132-deg shift in the phase angle between roll stimulation and horizontal eye position 2 h after landing. Neither of two from whom adequate data were collected exhibited increased horizontal eye movement amplitude or disturbance of voluntary pitch or roll body motion immediately postflight. These results are generally consistent with an otolith tilt-translation reinterpretation model and are being applied to the development of apparatus and procedures intended to preadapt astronauts to the sensory rearrangement of weightlessness.

Development and Application of the Elementary School Science Classroom Environment Scale (ESSCES): Measuring Student Perceptions of Constructivism within the Science Classroom

ERIC Educational Resources Information Center

Peoples, Shelagh M.; O'Dwyer, Laura M.; Wang, Yang; Brown, Jessica J.; Rosca, Camelia V.

2014-01-01

This article describes the development, validation and application of a Rasch-based instrument, the Elementary School Science Classroom Environment Scale (ESSCES), for measuring students' perceptions of constructivist practices within the elementary science classroom. The instrument, designed to complement the Reformed Teaching Observation…

Cloud Applications in Language Teaching: Examining Pre-Service Teachers' Expertise, Perceptions and Integration

ERIC Educational Resources Information Center

Aburezeq, Ibtehal Mahmoud; Dweikat, Fawzi Fayez Ishtaiwa

2017-01-01

This study examined pre-service teachers' expertise, perceptions and integration of cloud applications in teaching of Arabic and English. Questionnaires and semi-structured interviews were used as data collection methods. The findings of the study specified that pre-service teachers did not own sufficient expertise for effective integration of…

Fast, Capacious Disk Memory Device

NASA Technical Reports Server (NTRS)

Muller, Ronald M.

1990-01-01

Device for recording digital data on, and playing back data from, memory disks has high recording or playback rate and utilizes available recording area more fully. Two disks, each with own reading/writing head, used to record data at same time. Head on disk A operates on one of tracks numbered from outside in; head on disk B operates on track of same number in sequence from inside out. Underlying concept of device applicable to magnetic or optical disks.

Music Therapy in the Rehabilitation of Head-Injured Clients.

ERIC Educational Resources Information Center

Lee, Lissa

This paper summarizes research on clinical applications of music therapy with closed head injury clients. It offers a rationale for including music therapy in interdisciplinary rehabilitation. The Rancho Los Amigos Levels of Cognitive Functioning are outlined, and therapeutic assessment and treatment procedures are discussed. Rehabilitation…

22 CFR 192.23 - Administration of benefits.

Code of Federal Regulations, 2010 CFR

2010-04-01

....23 Foreign Relations DEPARTMENT OF STATE HOSTAGE RELIEF VICTIMS OF TERRORISM COMPENSATION Application.... (a) The Director General of the Department of State or Agency Head will issue certifications or other... State or Agency Head shall whenever possible promptly inform the chief legal officer of each U.S. State...

47 CFR 73.4250 - Subliminal perception.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 4 2014-10-01 2014-10-01 false Subliminal perception. 73.4250 Section 73.4250... Rules Applicable to All Broadcast Stations § 73.4250 Subliminal perception. (a) See Public Notice, FCC... Bulletin, “Subliminal Projection”, dated November 1977. [44 FR 36389, June 22, 1979] ...

47 CFR 73.4250 - Subliminal perception.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 4 2012-10-01 2012-10-01 false Subliminal perception. 73.4250 Section 73.4250... Rules Applicable to All Broadcast Stations § 73.4250 Subliminal perception. (a) See Public Notice, FCC... Bulletin, “Subliminal Projection”, dated November 1977. [44 FR 36389, June 22, 1979] ...

47 CFR 73.4250 - Subliminal perception.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 4 2013-10-01 2013-10-01 false Subliminal perception. 73.4250 Section 73.4250... Rules Applicable to All Broadcast Stations § 73.4250 Subliminal perception. (a) See Public Notice, FCC... Bulletin, “Subliminal Projection”, dated November 1977. [44 FR 36389, June 22, 1979] ...

47 CFR 73.4250 - Subliminal perception.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Subliminal perception. 73.4250 Section 73.4250... Rules Applicable to All Broadcast Stations § 73.4250 Subliminal perception. (a) See Public Notice, FCC... Bulletin, “Subliminal Projection”, dated November 1977. [44 FR 36389, June 22, 1979] ...

47 CFR 73.4250 - Subliminal perception.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 4 2011-10-01 2011-10-01 false Subliminal perception. 73.4250 Section 73.4250... Rules Applicable to All Broadcast Stations § 73.4250 Subliminal perception. (a) See Public Notice, FCC... Bulletin, “Subliminal Projection”, dated November 1977. [44 FR 36389, June 22, 1979] ...

Heat Perception and Aversive Learning in Honey Bees: Putative Involvement of the Thermal/Chemical Sensor AmHsTRPA

PubMed Central

Junca, Pierre; Sandoz, Jean-Christophe

2015-01-01

The recent development of the olfactory conditioning of the sting extension response (SER) has provided new insights into the mechanisms of aversive learning in honeybees. Until now, very little information has been gained concerning US detection and perception. In the initial version of SER conditioning, bees learned to associate an odor CS with an electric shock US. Recently, we proposed a modified version of SER conditioning, in which thermal stimulation with a heated probe is used as US. This procedure has the advantage of allowing topical US applications virtually everywhere on the honeybee body. In this study, we made use of this possibility and mapped thermal responsiveness on the honeybee body, by measuring workers' SER after applying heat on 41 different structures. We then show that bees can learn the CS-US association even when the heat US is applied on body structures that are not prominent sensory organs, here the vertex (back of the head) and the ventral abdomen. Next, we used a neuropharmalogical approach to evaluate the potential role of a recently described Transient Receptor Potential (TRP) channel, HsTRPA, on peripheral heat detection by bees. First, we applied HsTRPA activators to assess if such activation is sufficient for triggering SER. Second, we injected HsTRPA inhibitors to ask whether interfering with this TRP channel affects SER triggered by heat. These experiments suggest that HsTRPA may be involved in heat detection by bees, and represent a potential peripheral detection system in thermal SER conditioning. PMID:26635613

Public attitudes and risk perception toward land application of biosolids within the south-eastern United States.

PubMed

Robinson, Kevin G; Robinson, Carolyn H; Raup, Lauren A; Markum, Travis R

2012-05-15

A descriptive-correlational study of biosolids recycling was conducted in the south-eastern United States to assess current knowledge, attitudes and risk perceptions of participants in two communities that land apply biosolids as part of their waste management programs. One community, Amelia County VA, has been outspoken against biosolids recycling in the past, whereas the second community, Knoxville, TN region, has voiced few concerns about biosolids recycling. Additionally, gender differences within the entire study population were assessed. A 45-question telephone survey, utilizing a 4-point Likert scale, was developed and administered to 311 randomly selected adults in the two regions. Commonalities identified during the study revealed key risk perceptions by the public regarding biosolids regulations, treatment, and application. Given current perceptions and knowledge, respondents felt that the benefits derived from biosolids recycling do not offset the perceived health and safety risks. However, as distance between application and personal property increased, a decrease in opposition of biosolids reuse became evident for all respondents. Survey participants were dissatisfied with the level of stakeholder involvement in research and decision-making processes concerning biosolids. The outspoken Amelia County residents perceived greater health risks due to inadequate treatment of biosolids and odorous emissions during the application process than the less engaged Knox Metro respondents. Significant gender differences were observed with sampled females perceiving greater risks to health and safety from biosolids recycling than males. There was also indication that decisions and risks were not sufficiently communicated to the public, leading to respondents being inadequately informed about biosolids land application in both communities. Community-specific outreach programs must address these public risk perceptions and the differences in perception caused by gender and issue awareness to assist solid waste managers in developing and implementing successful biosolids land application systems that are acceptable to the public. Copyright © 2012 Elsevier Ltd. All rights reserved.

Optical Variability and Bottom Classification in Turbid Waters: HyMOM Predictions of the Light Field in Ports and Beneath Ship Hulls

DTIC Science & Technology

2006-09-30

dealing with the bleaching of corals and foraminifera and the photosynthesis of benthic plants. OBJECTIVES The initial objective of this work...of the structural light field around coral heads and other vertical structures should be included in future studies of bleaching of coral and... coral bleaching –Perceptibility problem begun for AUV @2m and @8m above 10m bottom –Higher resolution and higher-speed calculations (e.g. more

Development of a Device for Objective Assessment of Tinnitus in Humans

DTIC Science & Technology

2016-10-01

AWARD NUMBER: W81XWH-14-2-0180 TITLE: Development of a Device for Objective Assessment of Tinnitus in Humans PRINCIPAL INVESTIGATOR: Jeremy G...SUBTITLE Development of a Device for Objective Assessment of Tinnitus in Humans 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-14-2-0180 5c. PROGRAM...briefly (one paragraph) describes the subject, purpose and scope of the research. Tinnitus is the perception of sound in the ears or head when

Management of radiotherapy-induced salivary hypofunction and consequent xerostomia in patients with oral or head and neck cancer: meta-analysis and literature review.

PubMed

Lovelace, Tiffany L; Fox, Nyssa F; Sood, Amit J; Nguyen, Shaun A; Day, Terry A

2014-05-01

To analyze the efficacy of various treatment options for radiation-induced hyposalivation in patients with head and neck cancer. A literature review and meta-analysis was performed on all appropriate literature identified via MEDLINE/PubMed. Fourteen articles were identified that met inclusion criteria for review, and 8 articles qualified for inclusion in the meta-analysis. The available literature addressed both objective and subjective responses of hyposalivation, xerostomia, or both to cholinergic agonists (such as pilocarpine and cevimeline), salivary substitutes, hyperbaric oxygen, and acupuncture. This analysis indicated that cholinergic agonists were more effective in treating radiation-induced hyposalivation compared with salivary substitutes, hyperbaric oxygen, and acupuncture. However, other treatment modalities, such as salivary substitutes and hyperbaric oxygen, were also found to subjectively improve patients' perception of xerostomia. Copyright © 2014 Elsevier Inc. All rights reserved.

Toward a more nuanced perception of Alzheimer's disease: designing and testing a campaign advertisement.

PubMed

Van Gorp, Baldwin; Vercruysse, Tom; Van den Bulck, Jan

2012-09-01

Starting point of this study was the assumption that Alzheimer's disease is made worse for the person who has the disease by the negative regard in which the illness is held by society. The aim was to test by means of a campaign advertisement whether more nuanced counterframes could have an impact while remaining credible and comprehensible to the public. A sample of thousand people living in Belgium evaluated the campaign in an experimental design. This revealed that all the versions tested achieved a high average evaluation. The ad in which the heading referred to the fear of death and degeneration was judged to be most attention-grabbing, easier to understand, and more credible than the alternative heading with the idea that someone with Alzheimer's could still enjoy playing cards. Together, these findings provided a basis for the use of counterframes to generating a more nuanced image of Alzheimer's disease.

Vestibular system: the many facets of a multimodal sense.

PubMed

Angelaki, Dora E; Cullen, Kathleen E

2008-01-01

Elegant sensory structures in the inner ear have evolved to measure head motion. These vestibular receptors consist of highly conserved semicircular canals and otolith organs. Unlike other senses, vestibular information in the central nervous system becomes immediately multisensory and multimodal. There is no overt, readily recognizable conscious sensation from these organs, yet vestibular signals contribute to a surprising range of brain functions, from the most automatic reflexes to spatial perception and motor coordination. Critical to these diverse, multimodal functions are multiple computationally intriguing levels of processing. For example, the need for multisensory integration necessitates vestibular representations in multiple reference frames. Proprioceptive-vestibular interactions, coupled with corollary discharge of a motor plan, allow the brain to distinguish actively generated from passive head movements. Finally, nonlinear interactions between otolith and canal signals allow the vestibular system to function as an inertial sensor and contribute critically to both navigation and spatial orientation.

Is Heading in Youth Soccer Dangerous Play?

PubMed

O'Kane, John W

2016-01-01

Soccer is among the most popular youth sports with over 3 million youth players registered in the U.S. Soccer is unique in that players intentionally use their head to strike the ball, leading to concerns that heading could cause acute or chronic brain injury, especially in the immature brains of children. Pub Med search without date restriction was conducted in November 2014 and August 2015 using the terms soccer and concussion, heading and concussion, and youth soccer and concussion. 310 articles were identified and reviewed for applicable content specifically relating to youth athletes, heading, and/or acute or chronic brain injury from soccer. Soccer is a low-risk sport for catastrophic head injury, but concussions are relatively common and heading often plays a role. At all levels of play, concussions are more likely to occur in the act of heading than with other facets of the game. While concussion from heading the ball without other contact to the head appears rare in adult players, some data suggests children are more susceptible to concussion from heading primarily in game situations. Contributing factors include biomechanical forces, less developed technique, and the immature brain's susceptibility to injury. There is no evidence that heading in youth soccer causes any permanent brain injury and there is limited evidence that heading in youth soccer can cause concussion. A reasonable approach based on U.S. Youth Soccer recommendations is to teach heading after age 10 in controlled settings, and heading in games should be delayed until skill acquisition and physical maturity allow the youth player to head correctly with confidence.

Application of mitomycin-C for head and neck keloids.

PubMed

Stewart, Charles E; Kim, John Y

2006-12-01

Keloids of the head and neck are a relatively common entity in darker-skinned races, occurring in 5%-15% of skin wounds. Keloids are fibrotic lesions that are a result of an abnormal wound-healing process that lacks control of the mechanisms that regulate tissue repair and regeneration. The proliferation of normal tissue-healing processes results in scarring that enlarges well beyond the original wound margins. Many treatment modalities for keloids have been tried with variable amounts of success. Surgical excision, compressive therapy, silicon dressings, corticosteroid injections, radiation, cryotherapy, interferon therapy, and laser therapy have all been used alone or in combination. Despite this wide range of available treatments, recurrence rates typically remain in the 50%-70% range. In this study, we present our results in a series of 10 patients who were treated with surgical excision of head and neck keloids and the application of topical mitomycin-C. Mitomycin-C is a chemotherapeutic agent that inhibits DNA synthesis and fibroblast proliferation. It has been used in ophthalmologic procedures and airway surgery to decrease scar formation. In these 10 patients, we combined surgical excision of keloids with the application of topical mitomycin-C. The patients were then followed postoperatively for recurrence (range, 7-14 months). We have found topical application of mitomycin-C to be an effective therapy for prevention of keloid recurrence in the head and neck, with a success rate of 90% as reported in this series.

Assessing Mastery Motivation in a Head Start Sample.

ERIC Educational Resources Information Center

MacPhee, David; Fritz, Janet J.; Miller-Heyl, Jan; Hite, Judy

Although mastery motivation appears to predict school success, individual assessment of mastery motivation is too time consuming and limits the application of this research. This study examined the psychometric properties of the Dimensions of Mastery Questionnaire (DMQ). The study focused on the validity of the measure for Head Start parents,…

Measuring Executive Function Deficits Following Head Injury: An Application of SMS Simulation Technology

ERIC Educational Resources Information Center

Satish, Usha; Streufert, Siegfried; Eslinger, Paul J.

2006-01-01

Neuropsychological tests have limited sensitivity in identifying subtle residual cognitive impairments in patients with good medical recovery from head injury and post-concussive syndrome. Detecting and characterizing residual "real life" cognitive difficulties can be problematic for treatment purposes. This study investigated the usefulness of a…

External Cooling of the BWR Mark I and II Drywell Head as a Potential Accident Mitigation Measure – Scoping Assessment

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

Robb, Kevin R.

This report documents a scoping assessment of a potential accident mitigation action applicable to the US fleet of boiling water reactors with Mark I and II containments. The mitigation action is to externally flood the primary containment vessel drywell head using portable pumps or other means. A scoping assessment of the potential benefits of this mitigation action was conducted focusing on the ability to (1) passively remove heat from containment, (2) prevent or delay leakage through the drywell head seal (due to high temperatures and/or pressure), and (3) scrub radionuclide releases if the drywell head seal leaks.

Spatial orientation perception and reflexive eye movements--a perspective, an overview, and some clinical implications

NASA Technical Reports Server (NTRS)

Guedry, F. E.; Paloski, W. F. (Principal Investigator)

1996-01-01

When head motion includes a linear velocity component, eye velocity required to track an earth-fixed target depends upon: a) angular and linear head velocity, b) target distance, and c) direction of gaze relative to the motion trajectory. Recent research indicates that eye movements (LVOR), presumably otolith-mediated, partially compensate for linear velocity in small head excursions on small devices. Canal-mediated eye velocity (AVOR), otolith-mediated eye velocity (LVOR), and Ocular Torsion (OT) can be measured, one by one, on small devices. However, response dynamics that depend upon the ratio of linear to angular velocity in the motion trajectory and on subject orientation relative to the trajectory are present in a centrifuge paradigm. With this paradigm, two 3-min runs yields measures of: LVOR differentially modulated by different subject orientations in the two runs; OT dynamics in four conditions; two directions of "steady-state" OT, and two directions of AVOR. Efficient assessment of the dynamics (and of the underlying central integrative processes) may require a centrifuge radius of 1.0 meters or more. Clinical assessment of the spatial orientation system should include evaluation of central integrative processes that determine the dynamics of these responses.

Correction techniques for depth errors with stereo three-dimensional graphic displays

NASA Technical Reports Server (NTRS)

Parrish, Russell V.; Holden, Anthony; Williams, Steven P.

1992-01-01

Three-dimensional (3-D), 'real-world' pictorial displays that incorporate 'true' depth cues via stereopsis techniques have proved effective for displaying complex information in a natural way to enhance situational awareness and to improve pilot/vehicle performance. In such displays, the display designer must map the depths in the real world to the depths available with the stereo display system. However, empirical data have shown that the human subject does not perceive the information at exactly the depth at which it is mathematically placed. Head movements can also seriously distort the depth information that is embedded in stereo 3-D displays because the transformations used in mapping the visual scene to the depth-viewing volume (DVV) depend intrinsically on the viewer location. The goal of this research was to provide two correction techniques; the first technique corrects the original visual scene to the DVV mapping based on human perception errors, and the second (which is based on head-positioning sensor input data) corrects for errors induced by head movements. Empirical data are presented to validate both correction techniques. A combination of the two correction techniques effectively eliminates the distortions of depth information embedded in stereo 3-D displays.

Beating time: How ensemble musicians' cueing gestures communicate beat position and tempo.

PubMed

Bishop, Laura; Goebl, Werner

2018-01-01

Ensemble musicians typically exchange visual cues to coordinate piece entrances. "Cueing-in" gestures indicate when to begin playing and at what tempo. This study investigated how timing information is encoded in musicians' cueing-in gestures. Gesture acceleration patterns were expected to indicate beat position, while gesture periodicity, duration, and peak gesture velocity were expected to indicate tempo. Same-instrument ensembles (e.g., piano-piano) were expected to synchronize more successfully than mixed-instrument ensembles (e.g., piano-violin). Duos performed short passages as their head and (for violinists) bowing hand movements were tracked with accelerometers and Kinect sensors. Performers alternated between leader/follower roles; leaders heard a tempo via headphones and cued their partner in nonverbally. Violin duos synchronized more successfully than either piano duos or piano-violin duos, possibly because violinists were more experienced in ensemble playing than pianists. Peak acceleration indicated beat position in leaders' head-nodding gestures. Gesture duration and periodicity in leaders' head and bowing hand gestures indicated tempo. The results show that the spatio-temporal characteristics of cueing-in gestures guide beat perception, enabling synchronization with visual gestures that follow a range of spatial trajectories.

EARLY HEAD START FAMILIES' EXPERIENCES WITH STRESS: UNDERSTANDING VARIATIONS WITHIN A HIGH-RISK, LOW-INCOME SAMPLE.

PubMed

Hustedt, Jason T; Vu, Jennifer A; Bargreen, Kaitlin N; Hallam, Rena A; Han, Myae

2017-09-01

The federal Early Head Start program provides a relevant context to examine families' experiences with stress since participants qualify on the basis of poverty and risk. Building on previous research that has shown variations in demographic and economic risks even among qualifying families, we examined possible variations in families' perceptions of stress. Family, parent, and child data were collected to measure stressors and risk across a variety of domains in families' everyday lives, primarily from self-report measures, but also including assay results from child cortisol samples. A cluster analysis was employed to examine potential differences among groups of Early Head Start families. Results showed that there were three distinct subgroups of families, with some families perceiving that they experienced very high levels of stress while others perceived much lower levels of stress despite also experiencing poverty and heightened risk. These findings have important implications in that they provide an initial step toward distinguishing differences in low-income families' experiences with stress, thereby informing interventions focused on promoting responsive caregiving as a possible mechanism to buffer the effects of family and social stressors on young children. © 2017 Michigan Association for Infant Mental Health.

Job Restrictions for Healthcare Workers with Musculoskeletal Disorders: Consequences from the Superior's Viewpoint.

PubMed

Grataloup, M; Massardier-Pilonchéry, A; Bergeret, A; Fassier, Jean-Baptiste

2016-09-01

Objective Many workers suffer from musculoskeletal disorders. In France, occupational physicians are able to set job aptitude restrictions obliging employers to adapt the worker's job. The present study explored the impact of job restriction from the point of view of the employees' supervisors. Methods A qualitative study was conducted in 3 public hospitals. 12 focus groups were organized, involving 61 charge nurses and head nurses supervising 1 or more workers restricted for heavy lifting or repetitive movements. Discussions were recorded for qualitative thematic analysis. Results Charge and head nurses complained that aptitude restrictions were insufficiently precise, could not be respected and failed to mention residual capability. A context of personnel cuts, absenteeism and productivity demands entailed a need for polyvalence and reorganization threatening the permanence of adapted jobs. Job restrictions had several negative consequences for the charge and head nurses, including overwork, increased conflict, and feelings of isolation and organizational injustice. Conclusion Protecting the individual interests of workers with health issues may infringe on the interests of their supervisors and colleagues, whose perception of organizational justice may go some way to explaining the support or rejection they show toward restricted workers. This paradox should be explicitly explored and discussed.

Adaptive Changes in Sensorimotor Coordination and Motion Sickness Following Repeated Exposures to Virtual Environments

NASA Technical Reports Server (NTRS)

Harm, D. L.; Taylor, L. C.; Bloomberg, J. J.

2007-01-01

Virtual environments offer unique training opportunities, particularly for training astronauts and preadapting them to the novel sensory conditions of microgravity. Two unresolved human factors issues in virtual reality (VR) systems are: 1) potential "cybersickness", and 2) maladaptive sensorimotor performance following exposure to VR systems. Interestingly, these aftereffects are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. Initial interpretation of novel sensory information may be inappropriate and result in perceptual errors. Active exploratory behavior in a new environment, with resulting feedback and the formation of new associations between sensory inputs and response outputs, promotes appropriate perception and motor control in the new environment. Thus, people adapt to consistent, sustained alterations of sensory input such as those produced by microgravity, unilateral labyrinthectomy and experimentally produced stimulus rearrangements. The purpose of this research was to compare disturbances in sensorimotor coordination produced by dome and head-mounted virtual environment displays and to examine the effects of exposure duration, and repeated exposures to VR systems. The first study examined disturbances in balance control, and the second study examined disturbances in eye-head-hand (EHH) and eye-head coordination.

Experimental validation of a newly designed 6 degrees of freedom scanning laser head: Application to three-dimensional beam structure

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

Di Maio, D., E-mail: dario.dimaio@bristol.ac.uk; Copertaro, E.

2013-12-15

A new scanning laser head is designed to use single Laser Doppler Vibrometer (LDV) for performing measurements up to 6 degrees of freedom (DOF) at a target. The scanning head is supported by a rotating hollow shaft, which allows the laser beam to travel up to the scanning head from an opposite direction where an LDV is set up. The scanning head is made of a set of two mirrors, which deflects the laser beam with an angle so that the rotation of the scanning head produces a conical scan. When measurements are performed at the focal point of themore » conical scan then three translational vibration components can be measured, otherwise the very small circle scan, before and after the focal point, can measure up to 6 degrees of freedom, including three translations and three rotations. This paper presents the 6DOF scanning head and the measurements of 3D operational deflection shapes of a test structure.« less

Using visuo-kinetic virtual reality to induce illusory spinal movement: the MoOVi Illusion

PubMed Central

Smith, Ross T.; Hunter, Estin V.; Davis, Miles G.; Sterling, Michele; Moseley, G. Lorimer

2017-01-01

Background Illusions that alter perception of the body provide novel opportunities to target brain-based contributions to problems such as persistent pain. One example of this, mirror therapy, uses vision to augment perceived movement of a painful limb to treat pain. Since mirrors can’t be used to induce augmented neck or other spinal movement, we aimed to test whether such an illusion could be achieved using virtual reality, in advance of testing its potential therapeutic benefit. We hypothesised that perceived head rotation would depend on visually suggested movement. Method In a within-subjects repeated measures experiment, 24 healthy volunteers performed neck movements to 50o of rotation, while a virtual reality system delivered corresponding visual feedback that was offset by a factor of 50%–200%—the Motor Offset Visual Illusion (MoOVi)—thus simulating more or less movement than that actually occurring. At 50o of real-world head rotation, participants pointed in the direction that they perceived they were facing. The discrepancy between actual and perceived direction was measured and compared between conditions. The impact of including multisensory (auditory and visual) feedback, the presence of a virtual body reference, and the use of 360o immersive virtual reality with and without three-dimensional properties, was also investigated. Results Perception of head movement was dependent on visual-kinaesthetic feedback (p = 0.001, partial eta squared = 0.17). That is, altered visual feedback caused a kinaesthetic drift in the direction of the visually suggested movement. The magnitude of the drift was not moderated by secondary variables such as the addition of illusory auditory feedback, the presence of a virtual body reference, or three-dimensionality of the scene. Discussion Virtual reality can be used to augment perceived movement and body position, such that one can perform a small movement, yet perceive a large one. The MoOVi technique tested here has clear potential for assessment and therapy of people with spinal pain. PMID:28243537

Using visuo-kinetic virtual reality to induce illusory spinal movement: the MoOVi Illusion.

PubMed

Harvie, Daniel S; Smith, Ross T; Hunter, Estin V; Davis, Miles G; Sterling, Michele; Moseley, G Lorimer

2017-01-01

Illusions that alter perception of the body provide novel opportunities to target brain-based contributions to problems such as persistent pain. One example of this, mirror therapy, uses vision to augment perceived movement of a painful limb to treat pain. Since mirrors can't be used to induce augmented neck or other spinal movement, we aimed to test whether such an illusion could be achieved using virtual reality, in advance of testing its potential therapeutic benefit. We hypothesised that perceived head rotation would depend on visually suggested movement. In a within-subjects repeated measures experiment, 24 healthy volunteers performed neck movements to 50 o of rotation, while a virtual reality system delivered corresponding visual feedback that was offset by a factor of 50%-200%-the Motor Offset Visual Illusion (MoOVi)-thus simulating more or less movement than that actually occurring. At 50 o of real-world head rotation, participants pointed in the direction that they perceived they were facing. The discrepancy between actual and perceived direction was measured and compared between conditions. The impact of including multisensory (auditory and visual) feedback, the presence of a virtual body reference, and the use of 360 o immersive virtual reality with and without three-dimensional properties, was also investigated. Perception of head movement was dependent on visual-kinaesthetic feedback ( p  = 0.001, partial eta squared = 0.17). That is, altered visual feedback caused a kinaesthetic drift in the direction of the visually suggested movement. The magnitude of the drift was not moderated by secondary variables such as the addition of illusory auditory feedback, the presence of a virtual body reference, or three-dimensionality of the scene. Virtual reality can be used to augment perceived movement and body position, such that one can perform a small movement, yet perceive a large one. The MoOVi technique tested here has clear potential for assessment and therapy of people with spinal pain.

Associations of Eating Two Breakfasts With Childhood Overweight Status, Sociodemographics, and Parental Factors Among Preschool Students.

PubMed

Bruening, Meg; Afuso, Kevin; Mason, Maureen

2016-12-01

School breakfast may contribute to increased risk for obesity because children may be consuming two breakfasts: at home and at school. The purpose of this study is to determine the prevalence of preschoolers consuming two breakfasts and to assess relationships with overweight/obesity and other factors. Head Start parents (n = 273, 84.6% Hispanic) in the southwest completed cross-sectional surveys on child breakfast patterns and parental perceptions of school breakfast and personal breakfast consumption habits. Surveys were linked with sociodemographics and body mass index in Head Start databases in 2013. General estimating equation binomial models (schools as a random effect) were used to assess the relationship between two breakfasts (at home and school) and key variables, adjusting for gender, race, ethnicity, and household income. The prevalence of consuming two breakfasts was 34%. Children's overweight/obesity status was inversely related to two-breakfast consumption, but it was significant only for the Hispanic subgroup; the odds of being overweight/obese was 60% lower among those who ate two breakfasts (p < .05). The likelihood of consuming a second breakfast increased over twofold among children who woke up before 7 a.m. (p = .004). Among Hispanic families, a significant association was observed between children's two-breakfast consumption and parental perceptions about whether they perceived the breakfast at Head Start was culturally appropriate (p = .040). Not only was eating two breakfast not associated with obesity, the association was in the opposite of the expected direction and significant for Hispanic participants. Factors such as earlier wake-up time were related to reports of two breakfast intake. While more research is needed, these findings provide information for policy makers and practitioners; caution should be exercised when suggesting that breakfast programs may be related to the consumption of two breakfasts and the risk for childhood obesity, particularly among the preschool students in this study. © 2016 Society for Public Health Education.

Ultrasonic inspection and deployment apparatus

DOEpatents

Michaels, Jennifer E.; Michaels, Thomas E.; Mech, Jr., Stephen J.

1984-01-01

An ultrasonic inspection apparatus for the inspection of metal structures, especially installed pipes. The apparatus combines a specimen inspection element, an acoustical velocity sensing element, and a surface profiling element, all in one scanning head. A scanning head bellows contains a volume of oil above the pipe surface, serving as acoustical couplant between the scanning head and the pipe. The scanning head is mounted on a scanning truck which is mobile around a circular track surrounding the pipe. The scanning truck has sufficient motors, gears, and position encoders to allow the scanning head six degrees of motion freedom. A computer system continually monitors acoustical velocity, and uses that parameter to process surface profiling and inspection data. The profiling data is used to automatically control scanning head position and alignment and to define a coordinate system used to identify and interpret inspection data. The apparatus is suitable for highly automated, remote application in hostile environments, particularly high temperature and radiation areas.

Spatiotemporal frequency characteristics of cerebral oscillations during the perception of fundamental frequency contour changes in one-syllable intonation.

PubMed

Ueno, Sanae; Okumura, Eiichi; Remijn, Gerard B; Yoshimura, Yuko; Kikuchi, Mitsuru; Shitamichi, Kiyomi; Nagao, Kikuko; Mochiduki, Masayuki; Haruta, Yasuhiro; Hayashi, Norio; Munesue, Toshio; Tsubokawa, Tsunehisa; Oi, Manabu; Nakatani, Hideo; Higashida, Haruhiro; Minabe, Yoshio

2012-05-02

Accurate perception of fundamental frequency (F0) contour changes in the human voice is important for understanding a speaker's intonation, and consequently also his/her attitude. In this study, we investigated the neural processes involved in the perception of F0 contour changes in the Japanese one-syllable interjection "ne" in 21 native-Japanese listeners. A passive oddball paradigm was applied in which "ne" with a high falling F0 contour, used when urging a reaction from the listener, was randomly presented as a rare deviant among a frequent "ne" syllable with a flat F0 contour (i.e., meaningless intonation). We applied an adaptive spatial filtering method to the neuromagnetic time course recorded by whole-head magnetoencephalography (MEG) and estimated the spatiotemporal frequency dynamics of event-related cerebral oscillatory changes in the oddball paradigm. Our results demonstrated a significant elevation of beta band event-related desynchronization (ERD) in the right temporal and frontal areas, in time windows from 100 to 300 and from 300 to 500 ms after the onset of deviant stimuli (high falling F0 contour). This is the first study to reveal detailed spatiotemporal frequency characteristics of cerebral oscillations during the perception of intonational (not lexical) F0 contour changes in the human voice. The results further confirmed that the right hemisphere is associated with perception of intonational F0 contour information in the human voice, especially in early time windows. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Kids' perception about epilepsy.

PubMed

Fernandes, Paula T; Cabral, Paula; Araújo, Ulisses; Noronha, Ana Lúcia A; Li, Li M

2005-06-01

Epilepsy remains a stigmatized condition. Lack of information has been pointed to as a cause of the perpetuation of stigma. Our goal was to survey children's perception of epilepsy. We used a questionnaire to determine if the children knew what epilepsy is and, if they did not know, what did they think epilepsy is. Twenty-nine children (15 girls; mean age 10 years, range 9-11 years) from a fourth-grade class of an elementary school in Campinas, Sao Paulo, Brazil, completed the questionnaires individually at the same time in the classroom. This took about 20 minutes. Only four children said they knew what epilepsy is: a disease of swallowing the tongue (3) and a disease that can kill (1). The perceptions of children who said they did not know what epilepsy is were: a disease that can kill, a disease of swallowing the tongue, a contagious disease, a serious illness, a head injury. Three children knew someone with epilepsy, and only two of them had said they knew what epilepsy is. The perceptions elicited from the children had a negative connotation; only one child mentioned a relationship between epilepsy and the brain. The spontaneous thoughts of children in this age group, without the contamination of political correctness, may reflect society's collective unconsciousness of the prejudice toward epilepsy and people with epilepsy and needs to be further investigated. Continuous, repetitive educational efforts are necessary in elementary school to change these negative perceptions of epilepsy in our society.

Head-Mounted Display Technology for Low Vision Rehabilitation and Vision Enhancement

PubMed Central

Ehrlich, Joshua R.; Ojeda, Lauro V.; Wicker, Donna; Day, Sherry; Howson, Ashley; Lakshminarayanan, Vasudevan; Moroi, Sayoko E.

2017-01-01

Purpose To describe the various types of head-mounted display technology, their optical and human factors considerations, and their potential for use in low vision rehabilitation and vision enhancement. Design Expert perspective. Methods An overview of head-mounted display technology by an interdisciplinary team of experts drawing on key literature in the field. Results Head-mounted display technologies can be classified based on their display type and optical design. See-through displays such as retinal projection devices have the greatest potential for use as low vision aids. Devices vary by their relationship to the user’s eyes, field of view, illumination, resolution, color, stereopsis, effect on head motion and user interface. These optical and human factors considerations are important when selecting head-mounted displays for specific applications and patient groups. Conclusions Head-mounted display technologies may offer advantages over conventional low vision aids. Future research should compare head-mounted displays to commonly prescribed low vision aids in order to compare their effectiveness in addressing the impairments and rehabilitation goals of diverse patient populations. PMID:28048975

The research on a novel type of the solar-blind UV head-mounted displays

NASA Astrophysics Data System (ADS)

Zhao, Shun-long

2011-08-01

Ultraviolet technology of detecting is playing a more and more important role in the field of civil application, especially in the corona discharge detection, in modern society. Now the UV imaging detector is one of the most important equipments in power equipment flaws detection. And the modern head-mounted displays (HMDs) have shown the applications in the fields of military, industry production, medical treatment, entertainment, 3D visualization, education and training. We applied the system of head-mounted displays to the UV image detection, and a novel type of head-mounted displays is presented: the solar-blind UV head-mounted displays. And the structure is given. By the solar-blind UV head-mounted displays, a real-time, isometric and visible image of the corona discharge is correctly displayed upon the background scene where it exists. The user will see the visible image of the corona discharge on the real scene rather than on a small screen. Then the user can easily find out the power equipment flaws and repair them. Compared with the traditional UV imaging detector, the introducing of the HMDs simplifies the structure of the whole system. The original visible spectrum optical system is replaced by the eye in the solar-blind UV head-mounted displays. And the optical image fusion technology would be used rather than the digital image fusion system which is necessary in traditional UV imaging detector. That means the visible spectrum optical system and digital image fusion system are not necessary. This makes the whole system cheaper than the traditional UV imaging detector. Another advantage of the solar-blind UV head-mounted displays is that the two hands of user will be free. So while observing the corona discharge the user can do some things about it. Therefore the solar-blind UV head-mounted displays can make the corona discharge expose itself to the user in a better way, and it will play an important role in corona detection in the future.

Integrating public risk perception into formal natural hazard risk assessment

NASA Astrophysics Data System (ADS)

Plattner, Th.; Plapp, T.; Hebel, B.

2006-06-01

An urgent need to take perception into account for risk assessment has been pointed out by relevant literature, its impact in terms of risk-related behaviour by individuals is obvious. This study represents an effort to overcome the broadly discussed question of whether risk perception is quantifiable or not by proposing a still simple but applicable methodology. A novel approach is elaborated to obtain a more accurate and comprehensive quantification of risk in comparison to present formal risk evaluation practice. A consideration of relevant factors enables a explicit quantification of individual risk perception and evaluation. The model approach integrates the effective individual risk reff and a weighted mean of relevant perception affecting factors PAF. The relevant PAF cover voluntariness of risk-taking, individual reducibility of risk, knowledge and experience, endangerment, subjective damage rating and subjective recurrence frequency perception. The approach assigns an individual weight to each PAF to represent its impact magnitude. The quantification of these weights is target-group-dependent (e.g. experts, laypersons) and may be effected by psychometric methods. The novel approach is subject to a plausibility check using data from an expert-workshop. A first model application is conducted by means of data of an empirical risk perception study in Western Germany to deduce PAF and weight quantification as well as to confirm and evaluate model applicbility and flexibility. Main fields of application will be a quantification of risk perception by individual persons in a formal and technical way e.g. for the purpose of risk communication issues in illustrating differing perspectives of experts and non-experts. For decision making processes this model will have to be applied with caution, since it is by definition not designed to quantify risk acceptance or risk evaluation. The approach may well explain how risk perception differs, but not why it differs. The formal model generates only "snap shots" and considers neither the socio-cultural nor the historical context of risk perception, since it is a highly individualistic and non-contextual approach.

Treatment of human head lice infestations in a single application with a new galenic lotion.

PubMed

Militão de Sousa, F; Vasconcelos, A W; de Nadon, J; Duhot, P-Y

2010-10-01

To evaluate the efficiency and safety of a new galenic meta-emulsion for the treatment of human head lice (Pediculus capitis) in a single application. A controlled clinical study was conducted comparing lice infestation and nit hatching observed before and after a treatment in a single application. Eighty-two of the 87 children included completed the study. An infestation control was performed on 36 and 46 children, 8 and 24 h respectively after application. Five days later, a meticulous hair examination was carried out to check that the lice infestation was completely cured. After a single application of the lotion being tested, an examination of the scalp with a head lice detection comb, as well as an examination of the rinsing water and the towel used for drying after washing, showed that out of the total 1285 lice, there were no live lice. The percentage of nits hatching before treatment was close to 70%. In comparison, after an 8-h treatment (t(+8)), the percentage of nits hatching was 2.1%, with only 0.35% of living nymphs. After a 24-h treatment (t(+24)), 1.9% hatched with 0.38% living nymphs. Nymphs were revealed to be non-viable. After 5 days (t(+120)), no living adult or immature lice were found on the subjects tested. Moreover, observation of tolerance levels to this treatment at days 1, 5 and 12 showed no side effects. The specific galenic lotion completely cured head lice infestation in the population studied in a single application. The lotion, a patented meta-emulsion, has a mechanical action that asphyxiates lice and nits. Considering the advantages of the single application, the possibility of complete concomitant therapeutics for a whole school population within only 1 day and the high level of tolerance to this treatment, this approach seems simple and promising.

Teachers' Perceptions on Application of 2013 Curriculum for Elementary School in Medan

ERIC Educational Resources Information Center

Zulhernanda, Windha

2018-01-01

Curriculum is a set of educational design programs as a guide for learning activities. Recent changes in curriculum implementation in education have an impact on teachers in implementing them.This study investigated about the teacher perception on application the newest curriculum such as the 2013 curriclum for elementary school in Medan,…

Gender Divide and Acceptance of Collaborative Web 2.0 Applications for Learning in Higher Education

ERIC Educational Resources Information Center

Huang, Wen-Hao David; Hood, Denice Ward; Yoo, Sun Joo

2013-01-01

Situated in the gender digital divide framework, this survey study investigated the role of computer anxiety in influencing female college students' perceptions toward Web 2.0 applications for learning. Based on 432 college students' "Web 2.0 for learning" perception ratings collected by relevant categories of "Unified Theory of Acceptance and Use…

Student Computer Attitudes, Experience and Perceptions about the Use of Two Software Applications in Building Engineering

ERIC Educational Resources Information Center

Chiner, Esther; Garcia-Vera, Victoria E.

2017-01-01

The purpose of this study was to examine students' computer attitudes and experience, as well as students' perceptions about the use of two specific software applications (Google Drive Spreadsheets and Arquimedes) in the Building Engineering context. The relationships among these variables were also examined. Ninety-two students took part in this…

Dynamic Response and Residual Helmet Liner Crush Using Cadaver Heads and Standard Headforms.

PubMed

Bonin, S J; Luck, J F; Bass, C R; Gardiner, J C; Onar-Thomas, A; Asfour, S S; Siegmund, G P

2017-03-01

Biomechanical headforms are used for helmet certification testing and reconstructing helmeted head impacts; however, their biofidelity and direct applicability to human head and helmet responses remain unclear. Dynamic responses of cadaver heads and three headforms and residual foam liner deformations were compared during motorcycle helmet impacts. Instrumented, helmeted heads/headforms were dropped onto the forehead region against an instrumented flat anvil at 75, 150, and 195 J. Helmets were CT scanned to quantify maximum liner crush depth and crush volume. General linear models were used to quantify the effect of head type and impact energy on linear acceleration, head injury criterion (HIC), force, maximum liner crush depth, and liner crush volume and regression models were used to quantify the relationship between acceleration and both maximum crush depth and crush volume. The cadaver heads generated larger peak accelerations than all three headforms, larger HICs than the International Organization for Standardization (ISO), larger forces than the Hybrid III and ISO, larger maximum crush depth than the ISO, and larger crush volumes than the DOT. These significant differences between the cadaver heads and headforms need to be accounted for when attempting to estimate an impact exposure using a helmet's residual crush depth or volume.

Perception and Communication.

ERIC Educational Resources Information Center

Wakefield, Beverly

The purpose of this booklet is to provide a summary of perception research and to suggest practical applications which will improve students' and teachers' communication ability. The "theory" section of this work is devoted to the definition of perception as a selective process, dependent on such factors as acuity of sensory equipment, physical…

Magnetic bearings for a high-performance optical disk buffer, volume 1

NASA Technical Reports Server (NTRS)

Hockney, Richard; Adler, Karen; Anastas, George, Jr.; Downer, James; Flynn, Frederick; Goldie, James; Gondhalekar, Vijay; Hawkey, Timothy; Johnson, Bruce

1990-01-01

The innovation investigated in this project was the application of magnetic bearing technology to the translator head of an optical-disk data storage device. Both the capability for space-based applications and improved performance are expected to result. The phase 1 effort produced: (1) detailed specifications for both the translator-head and rotary-spindel bearings; (2) candidate hardware configurations for both bearings with detail definition for the translator head; (3) required characteristics for the magnetic bearing control loops; (4) position sensor selection; and (5) definition of the required electronic functions. The principal objective of Phase 2 was the design, fabrication, assembly, and test of the magnetic bearing system for the translator head. The scope of work included: (1) mechanical design of each of the required components; (2) electrical design of the required circuitry; (3) fabrication of the component parts and bread-board electronics; (4) generation of a test plan; and (5) integration of the prototype unit and performance testing. The project has confirmed the applicability of magnetic bearing technology to suspension of the translator head of the optical disk device, and demonstrated the achievement of all performance objectives. The magnetic bearing control loops perform well, achieving 100 Hz nominal bandwidth with phase margins between 37 and 63 degrees. The worst-case position resolution is 0.02 micron in the displacement loops and 1 micron rad in the rotation loops, The system is very robust to shock disturbances, recovering smoothly even when collisions occur between the translator and frame. The unique start-up/shut-down circuit has proven very effective.

Refinement of the Hybrid Neuroendovascular Operating Suite: Current and Future Applications.

PubMed

Ashour, Ramsey; See, Alfred P; Dasenbrock, Hormuzdiyar H; Khandelwal, Priyank; Patel, Nirav J; Belcher, Bianca; Aziz-Sultan, Mohammad Ali

2016-07-01

In early-generation hybrid biplane endovascular operating rooms, switching from surgical to angiographic position is cumbersome. In this report, we highlight the unique design of a new hybrid neuroendovascular operating suite that allows surgical access to the head while keeping the biplane system over the lower body of the patient. Current and future hybrid neuroendovascular operating suite applications are discussed. We collaborated with engineers to implement the following modifications to the design of the angiographic system: translation of the bed toward the feet to allow biplane cerebral imaging in the head-side position and the biplane left-side position; translation of the base of the A-plane C-arm away from the feet to allow increased operator space at the head of the bed and to allow cerebral imaging in both the head-side and left-side positions; use of a specialized boom mount for the display panel to increase mobility; and use of a radiolucent tabletop with attachments for the headrest or radiolucent head clamp system. The modified hybrid neuroendovascular operating suite allows for seamless transition between surgical and angiographic positions within seconds, improving workflow efficiency and decreasing procedure time as compared with early-generation hybrid rooms. Combined endovascular and surgical applications are facilitated by co-locating their respective technologies and refining the ergonomics of the system to ease transition between both sets of technologies. In so doing, hybrid neuroendovascular operating suites can be anticipated to improve patient outcomes, generate novel treatment paradigms, and improve time and cost efficiency. Copyright © 2016. Published by Elsevier Inc.

Research on dynamic performance design of mobile phone application based on context awareness

NASA Astrophysics Data System (ADS)

Bo, Zhang

2018-05-01

It aims to explore the dynamic performance of different mobile phone applications and the user's cognitive differences, reduce the cognitive burden, and enhance the sense of experience. By analyzing the dynamic design performance in four different interactive contexts, and constructing the framework of information service process in the interactive context perception and the two perception principles of the cognitive consensus between designer and user, and the two kinds of knowledge in accordance with the perception principles. The analysis of the context will help users sense the dynamic performance more intuitively, so that the details of interaction will be performed more vividly and smoothly, thus enhance user's experience in the interactive process. The common perception experience enables designers and users to produce emotional resonance in different interactive contexts, and help them achieve rapid understanding of interactive content and perceive the logic and hierarchy of the content and the structure, therefore the effectiveness of mobile applications will be improved.

Awareness on adverse effects of nanotechnology increases negative perception among public: survey study from Singapore

NASA Astrophysics Data System (ADS)

George, Saji; Kaptan, Gulbanu; Lee, Joel; Frewer, Lynn

2014-12-01

As has been demonstrated by recent societal controversies associated with the introduction of novel technologies, societal acceptance of a technology and its applications is shaped by consumers' perceived risks and benefits. The research reported here investigates public perceptions of nanotechnology in Singapore, where technological innovation is an established part of the economy, and it might be expected that consumer perceptions of risk are low, and those of benefit are high. The contribution of socio-demographic variables, knowledge level and exposure to risk information in shaping risk perception about nanotechnology applications within different application sectors were analysed. About 80 % of respondents have some understanding of nanotechnology, 60 % report having heard some negative information, and 39 % perceive nanotechnology as beneficial, while 27.5 % perceive it as risky. Nanotechnology application in food was reported to cause the most concern in the consumers included in the sample. Two-step cluster analysis of the data enabled grouping of respondents into those who expressed `less concern' or `more concern' based on their average scores for concern levels expressed with applications of nanotechnology in different sectors. Profiling of these clusters revealed that, apart from various socio-demographic factors, exposure to risk-related information, rather than awareness in nanotechnology itself, resulted in respondents expressing greater concern about nanotechnology applications. The results provide evidence upon which regulatory agencies and industries can base policies regarding informed risk-benefit communication and management associated with the introduction of commercial applications of nanotechnology.