Modeling the convergence accommodation of stereo vision for binocular endoscopy.
Gao, Yuanqian; Li, Jinhua; Li, Jianmin; Wang, Shuxin
2018-02-01
The stereo laparoscope is an important tool for achieving depth perception in robot-assisted minimally invasive surgery (MIS). A dynamic convergence accommodation algorithm is proposed to improve the viewing experience and achieve accurate depth perception. Based on the principle of the human vision system, a positional kinematic model of the binocular view system is established. The imaging plane pair is rectified to ensure that the two rectified virtual optical axes intersect at the fixation target to provide immersive depth perception. Stereo disparity was simulated with the roll and pitch movements of the binocular system. The chessboard test and the endoscopic peg transfer task were performed, and the results demonstrated the improved disparity distribution and robustness of the proposed convergence accommodation method with respect to the position of the fixation target. This method offers a new solution for effective depth perception with the stereo laparoscopes used in robot-assisted MIS. Copyright © 2017 John Wiley & Sons, Ltd.
Choi, Hyunseok; Cho, Byunghyun; Masamune, Ken; Hashizume, Makoto; Hong, Jaesung
2016-03-01
Depth perception is a major issue in augmented reality (AR)-based surgical navigation. We propose an AR and virtual reality (VR) switchable visualization system with distance information, and evaluate its performance in a surgical navigation set-up. To improve depth perception, seamless switching from AR to VR was implemented. In addition, the minimum distance between the tip of the surgical tool and the nearest organ was provided in real time. To evaluate the proposed techniques, five physicians and 20 non-medical volunteers participated in experiments. Targeting error, time taken, and numbers of collisions were measured in simulation experiments. There was a statistically significant difference between a simple AR technique and the proposed technique. We confirmed that depth perception in AR could be improved by the proposed seamless switching between AR and VR, and providing an indication of the minimum distance also facilitated the surgical tasks. Copyright © 2015 John Wiley & Sons, Ltd.
Matching and correlation computations in stereoscopic depth perception.
Doi, Takahiro; Tanabe, Seiji; Fujita, Ichiro
2011-03-02
A fundamental task of the visual system is to infer depth by using binocular disparity. To encode binocular disparity, the visual cortex performs two distinct computations: one detects matched patterns in paired images (matching computation); the other constructs the cross-correlation between the images (correlation computation). How the two computations are used in stereoscopic perception is unclear. We dissociated their contributions in near/far discrimination by varying the magnitude of the disparity across separate sessions. For small disparity (0.03°), subjects performed at chance level to a binocularly opposite-contrast (anti-correlated) random-dot stereogram (RDS) but improved their performance with the proportion of contrast-matched (correlated) dots. For large disparity (0.48°), the direction of perceived depth reversed with an anti-correlated RDS relative to that for a correlated one. Neither reversed nor normal depth was perceived when anti-correlation was applied to half of the dots. We explain the decision process as a weighted average of the two computations, with the relative weight of the correlation computation increasing with the disparity magnitude. We conclude that matching computation dominates fine depth perception, while both computations contribute to coarser depth perception. Thus, stereoscopic depth perception recruits different computations depending on the disparity magnitude.
Perception of CPR quality: Influence of CPR feedback, Just-in-Time CPR training and provider role.
Cheng, Adam; Overly, Frank; Kessler, David; Nadkarni, Vinay M; Lin, Yiqun; Doan, Quynh; Duff, Jonathan P; Tofil, Nancy M; Bhanji, Farhan; Adler, Mark; Charnovich, Alex; Hunt, Elizabeth A; Brown, Linda L
2015-02-01
Many healthcare providers rely on visual perception to guide cardiopulmonary resuscitation (CPR), but little is known about the accuracy of provider perceptions of CPR quality. We aimed to describe the difference between perceived versus measured CPR quality, and to determine the impact of provider role, real-time visual CPR feedback and Just-in-Time (JIT) CPR training on provider perceptions. We conducted secondary analyses of data collected from a prospective, multicenter, randomized trial of 324 healthcare providers who participated in a simulated cardiac arrest scenario between July 2012 and April 2014. Participants were randomized to one of four permutations of: JIT CPR training and real-time visual CPR feedback. We calculated the difference between perceived and measured quality of CPR and reported the proportion of subjects accurately estimating the quality of CPR within each study arm. Participants overestimated achieving adequate chest compression depth (mean difference range: 16.1-60.6%) and rate (range: 0.2-51%), and underestimated chest compression fraction (0.2-2.9%) across all arms. Compared to no intervention, the use of real-time feedback and JIT CPR training (alone or in combination) improved perception of depth (p<0.001). Accurate estimation of CPR quality was poor for chest compression depth (0-13%), rate (5-46%) and chest compression fraction (60-63%). Perception of depth is more accurate in CPR providers versus team leaders (27.8% vs. 7.4%; p=0.043) when using real-time feedback. Healthcare providers' visual perception of CPR quality is poor. Perceptions of CPR depth are improved by using real-time visual feedback and with prior JIT CPR training. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Murugesan, Yahini Prabha; Alsadoon, Abeer; Manoranjan, Paul; Prasad, P W C
2018-06-01
Augmented reality-based surgeries have not been successfully implemented in oral and maxillofacial areas due to limitations in geometric accuracy and image registration. This paper aims to improve the accuracy and depth perception of the augmented video. The proposed system consists of a rotational matrix and translation vector algorithm to reduce the geometric error and improve the depth perception by including 2 stereo cameras and a translucent mirror in the operating room. The results on the mandible/maxilla area show that the new algorithm improves the video accuracy by 0.30-0.40 mm (in terms of overlay error) and the processing rate to 10-13 frames/s compared to 7-10 frames/s in existing systems. The depth perception increased by 90-100 mm. The proposed system concentrates on reducing the geometric error. Thus, this study provides an acceptable range of accuracy with a shorter operating time, which provides surgeons with a smooth surgical flow. Copyright © 2018 John Wiley & Sons, Ltd.
Various Measures of the Effectiveness of Yellow Goggles
1980-10-08
technique which is widely used r.o improve vision under these conditions is the use of yellow goggles. Skiers commonly don yellow goggles...different laboratory studies are presented. Two of the studies were of depth perception, since skiers believe that yellow goggles help them...selected for measurement because of practical considerations and theoretical implications. EXPERIMENTS ON DEPTH PERCEPTION Background Since skiers
Path perception during rotation: influence of instructions, depth range, and dot density
NASA Technical Reports Server (NTRS)
Li, Li; Warren, William H Jr
2004-01-01
How do observers perceive their direction of self-motion when traveling on a straight path while their eyes are rotating? Our previous findings suggest that information from retinal flow and extra-retinal information about eye movements are each sufficient to solve this problem for both perception and active control of self-motion [Vision Res. 40 (2000) 3873; Psych. Sci. 13 (2002) 485]. In this paper, using displays depicting translation with simulated eye rotation, we investigated how task variables such as instructions, depth range, and dot density influenced the visual system's reliance on retinal vs. extra-retinal information for path perception during rotation. We found that path errors were small when observers expected to travel on a straight path or with neutral instructions, but errors increased markedly when observers expected to travel on a curved path. Increasing depth range or dot density did not improve path judgments. We conclude that the expectation of the shape of an upcoming path can influence the interpretation of the ambiguous retinal flow. A large depth range and dense motion parallax are not essential for accurate path perception during rotation, but reference objects and a large field of view appear to improve path judgments.
Enhancing Motion-In-Depth Perception of Random-Dot Stereograms.
Zhang, Di; Nourrit, Vincent; De Bougrenet de la Tocnaye, Jean-Louis
2018-07-01
Random-dot stereograms have been widely used to explore the neural mechanisms underlying binocular vision. Although they are a powerful tool to stimulate motion-in-depth (MID) perception, published results report some difficulties in the capacity to perceive MID generated by random-dot stereograms. The purpose of this study was to investigate whether the performance of MID perception could be improved using an appropriate stimulus design. Sixteen inexperienced observers participated in the experiment. A training session was carried out to improve the accuracy of MID detection before the experiment. Four aspects of stimulus design were investigated: presence of a static reference, background texture, relative disparity, and stimulus contrast. Participants' performance in MID direction discrimination was recorded and compared to evaluate whether varying these factors helped MID perception. Results showed that only the presence of background texture had a significant effect on MID direction perception. This study provides suggestions for the design of 3D stimuli in order to facilitate MID perception.
Wieringa, Fokko P.; Bouma, Henri; Eendebak, Pieter T.; van Basten, Jean-Paul A.; Beerlage, Harrie P.; Smits, Geert A. H. J.; Bos, Jelte E.
2014-01-01
Abstract. In comparison to open surgery, endoscopic surgery offers impaired depth perception and narrower field-of-view. To improve depth perception, the Da Vinci robot offers three-dimensional (3-D) video on the console for the surgeon but not for assistants, although both must collaborate. We improved the shared perception of the whole surgical team by connecting live 3-D monitors to all three available Da Vinci generations, probed user experience after two years by questionnaire, and compared time measurements of a predefined complex interaction task performed with a 3-D monitor versus two-dimensional. Additionally, we investigated whether the complex mental task of reconstructing a 3-D overview from an endoscopic video can be performed by a computer and shared among users. During the study, 925 robot-assisted laparoscopic procedures were performed in three hospitals, including prostatectomies, cystectomies, and nephrectomies. Thirty-one users participated in our questionnaire. Eighty-four percent preferred 3-D monitors and 100% reported spatial-perception improvement. All participating urologists indicated quicker performance of tasks requiring delicate collaboration (e.g., clip placement) when assistants used 3-D monitors. Eighteen users participated in a timing experiment during a delicate cooperation task in vitro. Teamwork was significantly (40%) faster with the 3-D monitor. Computer-generated 3-D reconstructions from recordings offered very wide interactive panoramas with educational value, although the present embodiment is vulnerable to movement artifacts. PMID:26158026
NASA Astrophysics Data System (ADS)
Weigelt, K.; Wiemeyer, J.
2014-03-01
This work examines the impact of content and presentation parameters in 2D versus 3D on depth perception and spatial presence, and provides guidelines for stereoscopic content development for 3D sports TV broadcasts and cognate subjects. Under consideration of depth perception and spatial presence experience, a preliminary study with 8 participants (sports: soccer and boxing) and a main study with 31 participants (sports: soccer and BMX-Miniramp) were performed. The dimension (2D vs. 3D) and camera position (near vs. far) were manipulated for soccer and boxing. In addition for soccer, the field of view (small vs. large) was examined. Moreover, the direction of motion (horizontal vs. depth) was considered for BMX-Miniramp. Subjective assessments, behavioural tests and qualitative interviews were implemented. The results confirm a strong effect of 3D on both depth perception and spatial presence experience as well as selective influences of camera distance and field of view. The results can improve understanding of the perception and experience of 3D TV as a medium. Finally, recommendations are derived on how to use various 3D sports ideally as content for TV broadcasts.
Gasco, Jaime; Patel, Achal; Luciano, Cristian; Holbrook, Thomas; Ortega-Barnett, Juan; Kuo, Yong-Fang; Rizzi, Silvio; Kania, Patrick; Banerjee, Pat; Roitberg, Ben Z
2013-12-01
To understand the perceived utility of a novel simulator to improve operative skill, eye-hand coordination, and depth perception. We used the ImmersiveTouch simulation platform (ImmersiveTouch, Inc., Chicago, Illinois, USA) in two U.S. Accreditation Council for Graduate Medical Education-accredited neurosurgical training programs: the University of Chicago and the University of Texas Medical Branch. A total of 54 trainees participated in the study, which consisted of 14 residents (group A), 20 senior medical students who were neurosurgery candidates (group B), and 20 junior medical students (group C). The participants performed a simulation task that established bipolar hemostasis in a virtual brain cavity and provided qualitative feedback regarding perceived benefits in eye-hand coordination, depth perception, and potential to assist in improving operating skills. The perceived ability of the simulator to positively influence skills judged by the three groups: group A, residents; group B, senior medical students; and group C, junior medical students was, respectively, 86%, 100%, and 100% for eye-hand coordination; 86%, 100%, and 95% for depth perception; and 79%, 100%, and 100% for surgical skills in the operating room. From all groups, 96.2% found the simulation somewhat or very useful to improve eye-hand coordination, and 94% considered it beneficial to improve depth perception and operating room skills. This simulation module may be suitable for resident training, as well as for the development of career interest and skill acquisition; however, validation for this type of simulation needs to be further developed. Copyright © 2013 Elsevier Inc. All rights reserved.
Video-Based Method of Quantifying Performance and Instrument Motion During Simulated Phonosurgery
Conroy, Ellen; Surender, Ketan; Geng, Zhixian; Chen, Ting; Dailey, Seth; Jiang, Jack
2015-01-01
Objectives/Hypothesis To investigate the use of the Video-Based Phonomicrosurgery Instrument Tracking System to collect instrument position data during simulated phonomicrosurgery and calculate motion metrics using these data. We used this system to determine if novice subject motion metrics improved over 1 week of training. Study Design Prospective cohort study. Methods Ten subjects performed simulated surgical tasks once per day for 5 days. Instrument position data were collected and used to compute motion metrics (path length, depth perception, and motion smoothness). Data were analyzed to determine if motion metrics improved with practice time. Task outcome was also determined each day, and relationships between task outcome and motion metrics were used to evaluate the validity of motion metrics as indicators of surgical performance. Results Significant decreases over time were observed for path length (P <.001), depth perception (P <.001), and task outcome (P <.001). No significant change was observed for motion smoothness. Significant relationships were observed between task outcome and path length (P <.001), depth perception (P <.001), and motion smoothness (P <.001). Conclusions Our system can estimate instrument trajectory and provide quantitative descriptions of surgical performance. It may be useful for evaluating phonomicrosurgery performance. Path length and depth perception may be particularly useful indicators. PMID:24737286
ERIC Educational Resources Information Center
Kim, Jihyun; Youngs, Peter
2016-01-01
This study draws on institutional theory to examine teachers' and principals' perceptions of new teacher evaluation policies, factors that influence such perceptions and how such perceptions shape the implementation of the policies in Seoul (Korea) and Michigan (USA). The study featured in-depth interviews of 11 elementary school teachers and 4…
Student Perceptions of Service Quality in a Multi-Campus Higher Education System in Spain
ERIC Educational Resources Information Center
Gallifa, Josep; Batalle, Pere
2010-01-01
Purpose: This paper aims to present an in-depth case study with student perceptions of service quality, discussing the relevance of these perceptions for the important issue of quality improvement in higher education. Design/methodology/approach: The paper presents institutional research carried out in a multi-campus system in Spain made up of…
NASA Technical Reports Server (NTRS)
Busquets, Anthony M.; Parrish, Russell V.; Williams, Steven P.
1991-01-01
High-fidelity color pictorial displays that incorporate depth cues in the display elements are currently available. Depth cuing applied to advanced head-down flight display concepts potentially enhances the pilot's situational awareness and improves task performance. Depth cues provided by stereopsis exhibit constraints that must be fully understood so depth cuing enhancements can be adequately realized and exploited. A fundamental issue (the goal of this investigation) is whether the use of head-down stereoscopic displays in flight applications degrade the real-world depth perception of pilots using such displays. Stereoacuity tests are used in this study as the measure of interest. Eight pilots flew repeated simulated landing approaches using both nonstereo and stereo 3-D head-down pathway-in-the-sky displays. At this decision height of each approach (where the pilot changes to an out-the-window view to obtain real-world visual references) the pilots changed to a stereoacuity test that used real objects. Statistical analysis of stereoacuity measures (data for a control condition of no exposure to any electronic flight display compared with data for changes from nonstereo and from stereo displays) reveals no significant differences for any of the conditions. Therefore, changing from short-term exposure to a head-down stereo display has no more effect on real-world relative depth perception than does changing from a nonstereo display. However, depth perception effects based on sized and distance judgements and on long-term exposure remain issues to be investigated.
Depth Perception of Surgeons in Minimally Invasive Surgery.
Bogdanova, Rositsa; Boulanger, Pierre; Zheng, Bin
2016-10-01
Minimally invasive surgery (MIS) poses visual challenges to the surgeons. In MIS, binocular disparity is not freely available for surgeons, who are required to mentally rebuild the 3-dimensional (3D) patient anatomy from a limited number of monoscopic visual cues. The insufficient depth cues from the MIS environment could cause surgeons to misjudge spatial depth, which could lead to performance errors thus jeopardizing patient safety. In this article, we will first discuss the natural human depth perception by exploring the main depth cues available for surgeons in open procedures. Subsequently, we will reveal what depth cues are lost in MIS and how surgeons compensate for the incomplete depth presentation. Next, we will further expand our knowledge by exploring some of the available solutions for improving depth presentation to surgeons. Here we will review the innovative approaches (multiple 2D camera assembly, shadow introduction) and devices (3D monitors, head-mounted devices, and auto-stereoscopic monitors) for 3D image presentation from the past few years. © The Author(s) 2016.
Remote operation: a selective review of research into visual depth perception.
Reinhardt-Rutland, A H
1996-07-01
Some perceptual motor operations are performed remotely; examples include the handling of life-threatening materials and surgical procedures. A camera conveys the site of operation to a TV monitor, so depth perception relies mainly on pictorial information, perhaps with enhancement of the occlusion cue by motion. However, motion information such as motion parallax is not likely to be important. The effectiveness of pictorial information is diminished by monocular and binocular information conveying flatness of the screen and by difficulties in scaling: Only a degree of relative depth can be conveyed. Furthermore, pictorial information can mislead. Depth perception is probably adequate in remote operation, if target objects are well separated, with well-defined edges and familiar shapes. Stereoscopic viewing systems are being developed to introduce binocular information to remote operation. However, stereoscopic viewing is problematic because binocular disparity conflicts with convergence and monocular information. An alternative strategy to improve precision in remote operation may be to rely on individuals who lack binocular function: There is redundancy in depth information, and such individuals seem to compensate for the lack of binocular function.
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.
NASA Astrophysics Data System (ADS)
Kleiber, Michael; Winkelholz, Carsten
2008-02-01
The aim of the presented research was to quantify the distortion of depth perception when using stereoscopic displays. The visualization parameters of the used virtual reality system such as perspective, haploscopic separation and width of stereoscopic separation were varied. The experiment was designed to measure distortion in depth perception according to allocentric frames of reference. The results of the experiments indicate that some of the parameters have an antithetic effect which allows to compensate the distortion of depth perception for a range of depths. In contrast to earlier research which reported underestimation of depth perception we found that depth was overestimated when using true projection parameters according to the position of the eyes of the user and display geometry.
Roy, Alexis T; Penninger, Richard T; Pearl, Monica S; Wuerfel, Waldemar; Jiradejvong, Patpong; Carver, Courtney; Buechner, Andreas; Limb, Charles J
2016-02-01
Cochlear implant (CI) electrode arrays typically do not reach the most apical regions of the cochlea that intrinsically encode low frequencies. This may contribute to diminished implant-mediated musical sound quality perception. The objective of this study was to assess the effect of varying degrees of apical cochlear stimulation (measured by angular insertion depth) on musical sound quality discrimination. Increased apical cochlear stimulation will improve low-frequency perception and musical sound quality discrimination. Standard (31.5 mm, n = 17) and medium (24 mm, n = 8) array Med-EL CI users, and normal hearing (NH) listeners (n = 16) participated. Imaging confirmed angular insertion depth. Participants completed a musical discrimination task in which they listened to a real-world musical stimulus (labeled reference) and provided sound quality ratings to versions of the reference, which included a hidden reference and test stimuli with increasing amounts of low-frequency removal. Scores for each CI users were calculated on the basis of how much their ratings differed from NH listeners for each stimulus version. Medium array and standard users had significantly different insertion depths (389.4 ± 64.5 and 583.9 ± 78.5 degrees, respectively; p < .001). A significant Pearson's correlation was observed between angular insertion depth and the hidden reference scores (p < 0.05). CI users with greater apical stimulation made sound quality discriminations that more closely resembled those of NH controls for stimuli that contained low frequencies (< 200 Hz of information). These findings suggest that increased apical cochlear stimulation improves musical low-frequency perception, which may provide a more satisfactory music listening experience for CI users.
Disorders of motion and depth.
Nawrot, Mark
2003-08-01
Damage to the human homologue of area MT produces a motion perception deficit similar to that found in the monkey with MT lesions. Even temporary disruption of MT processing with transcranial magnetic stimulation can produce a temporary akinetopsia [127]. Motion perception deficits, however, also are found with a variety of subcortical lesions and other neurologic disorders that can best be described as causing a disconnection within the motion processing stream. The precise role of these subcortical structures, such as the cerebellum, remains to be determined. Simple motion perception, moreover, is only a part of MT function. It undoubtedly has an important role in the perception of depth from motion and stereopsis [112]. Psychophysical studies using aftereffects in normal observers suggest a link between stereo mechanisms and the perception of depth from motion [9-11]. There is even a simple correlation between stereo acuity and the perception of depth from motion [128]. Future studies of patients with cortical lesions will take a closer look at depth perception in association with motion perception and should provide a better understanding of how motion and depth are processed together.
Hibbard, Paul B; Scott-Brown, Kenneth C; Haigh, Emma C; Adrain, Melanie
2014-01-01
One of the greatest challenges in visual neuroscience is that of linking neural activity with perceptual experience. In the case of binocular depth perception, important insights have been achieved through comparing neural responses and the perception of depth, for carefully selected stimuli. One of the most important types of stimulus that has been used here is the anti-correlated random dot stereogram (ACRDS). In these stimuli, the contrast polarity of one half of a stereoscopic image is reversed. While neurons in cortical area V1 respond reliably to the binocular disparities in ACRDS, they do not create a sensation of depth. This discrepancy has been used to argue that depth perception must rely on neural activity elsewhere in the brain. Currently, the psychophysical results on which this argument rests are not clear-cut. While it is generally assumed that ACRDS do not support the perception of depth, some studies have reported that some people, some of the time, perceive depth in some types of these stimuli. Given the importance of these results for understanding the neural correlates of stereopsis, we studied depth perception in ACRDS using a large number of observers, in order to provide an unambiguous conclusion about the extent to which these stimuli support the perception of depth. We presented observers with random dot stereograms in which correlated dots were presented in a surrounding annulus and correlated or anti-correlated dots were presented in a central circular region. While observers could reliably report the depth of the central region for correlated stimuli, we found no evidence for depth perception in static or dynamic anti-correlated stimuli. Confidence ratings for stereoscopic perception were uniformly low for anti-correlated stimuli, but showed normal variation with disparity for correlated stimuli. These results establish that the inability of observers to perceive depth in ACRDS is a robust phenomenon.
Hibbard, Paul B.; Scott-Brown, Kenneth C.; Haigh, Emma C.; Adrain, Melanie
2014-01-01
One of the greatest challenges in visual neuroscience is that of linking neural activity with perceptual experience. In the case of binocular depth perception, important insights have been achieved through comparing neural responses and the perception of depth, for carefully selected stimuli. One of the most important types of stimulus that has been used here is the anti-correlated random dot stereogram (ACRDS). In these stimuli, the contrast polarity of one half of a stereoscopic image is reversed. While neurons in cortical area V1 respond reliably to the binocular disparities in ACRDS, they do not create a sensation of depth. This discrepancy has been used to argue that depth perception must rely on neural activity elsewhere in the brain. Currently, the psychophysical results on which this argument rests are not clear-cut. While it is generally assumed that ACRDS do not support the perception of depth, some studies have reported that some people, some of the time, perceive depth in some types of these stimuli. Given the importance of these results for understanding the neural correlates of stereopsis, we studied depth perception in ACRDS using a large number of observers, in order to provide an unambiguous conclusion about the extent to which these stimuli support the perception of depth. We presented observers with random dot stereograms in which correlated dots were presented in a surrounding annulus and correlated or anti-correlated dots were presented in a central circular region. While observers could reliably report the depth of the central region for correlated stimuli, we found no evidence for depth perception in static or dynamic anti-correlated stimuli. Confidence ratings for stereoscopic perception were uniformly low for anti-correlated stimuli, but showed normal variation with disparity for correlated stimuli. These results establish that the inability of observers to perceive depth in ACRDS is a robust phenomenon. PMID:24416195
Pollock, Brice; Burton, Melissa; Kelly, Jonathan W; Gilbert, Stephen; Winer, Eliot
2012-04-01
Stereoscopic depth cues improve depth perception and increase immersion within virtual environments (VEs). However, improper display of these cues can distort perceived distances and directions. Consider a multi-user VE, where all users view identical stereoscopic images regardless of physical location. In this scenario, cues are typically customized for one "leader" equipped with a head-tracking device. This user stands at the center of projection (CoP) and all other users ("followers") view the scene from other locations and receive improper depth cues. This paper examines perceived depth distortion when viewing stereoscopic VEs from follower perspectives and the impact of these distortions on collaborative spatial judgments. Pairs of participants made collaborative depth judgments of virtual shapes viewed from the CoP or after displacement forward or backward. Forward and backward displacement caused perceived depth compression and expansion, respectively, with greater compression than expansion. Furthermore, distortion was less than predicted by a ray-intersection model of stereo geometry. Collaboration times were significantly longer when participants stood at different locations compared to the same location, and increased with greater perceived depth discrepancy between the two viewing locations. These findings advance our understanding of spatial distortions in multi-user VEs, and suggest a strategy for reducing distortion.
Stereoscopic depth perception varies with hues
NASA Astrophysics Data System (ADS)
Chen, Zaiqing; Shi, Junsheng; Tai, Yonghang; Yun, Lijun
2012-09-01
The contribution of color information to stereopsis is controversial, and whether the stereoscopic depth perception varies with chromaticity is ambiguous. This study examined the changes in depth perception caused by hue variations. Based on the fact that a greater disparity range indicates more efficient stereoscopic perception, the effect of hue variations on depth perception was evaluated through the disparity range with random-dot stereogram stimuli. The disparity range was obtained by constant-stimulus method for eight chromaticity points sampled from the CIE 1931 chromaticity diagram. Eight sample points include four main color hues: red, yellow, green, and blue at two levels of chroma. The results show that the disparity range for the yellow hue is greater than the red hue, the latter being greater than the blue hue and the disparity range for green hue is smallest. We conclude that the perceived depth is not the same for different hues for a given size of disparity. We suggest that the stereoscopic depth perception can vary with chromaticity.
How to reinforce perception of depth in single two-dimensional pictures
NASA Technical Reports Server (NTRS)
Nagata, S.
1989-01-01
The physical conditions of the display of single 2-D pictures, which produce images realistically, were studied by using the characteristics of the intake of the information for visual depth perception. Depth sensitivity, which is defined as the ratio of viewing distance to depth discrimination threshold, was introduced in order to evaluate the availability of various cues for depth perception: binocular parallax, motion parallax, accommodation, convergence, size, texture, brightness, and air-perspective contrast. The effects of binocular parallax in different conditions, the depth sensitivity of which is greatest at a distance of up to about 10 m, were studied with the new versatile stereoscopic display. From these results, four conditions to reinforce the perception of depth in single pictures were proposed, and these conditions are met by the old viewing devices and the new high-definition and wide television displays.
Learning Experiences of University Biology Faculty: A Qualitative Pilot Study
ERIC Educational Resources Information Center
Kusch, Jennifer
2016-01-01
The study described in this article incorporates qualitative research through in-depth, individual, structured interviews with 12 biology faculty from two Midwestern universities to explore perceptions about how they have learned to teach and how they work to improve their skills.
Virtual reality hardware and graphic display options for brain-machine interfaces
Marathe, Amar R.; Carey, Holle L.; Taylor, Dawn M.
2009-01-01
Virtual reality hardware and graphic displays are reviewed here as a development environment for brain-machine interfaces (BMIs). Two desktop stereoscopic monitors and one 2D monitor were compared in a visual depth discrimination task and in a 3D target-matching task where able-bodied individuals used actual hand movements to match a virtual hand to different target hands. Three graphic representations of the hand were compared: a plain sphere, a sphere attached to the fingertip of a realistic hand and arm, and a stylized pacman-like hand. Several subjects had great difficulty using either stereo monitor for depth perception when perspective size cues were removed. A mismatch in stereo and size cues generated inappropriate depth illusions. This phenomenon has implications for choosing target and virtual hand sizes in BMI experiments. Target matching accuracy was about as good with the 2D monitor as with either 3D monitor. However, users achieved this accuracy by exploring the boundaries of the hand in the target with carefully controlled movements. This method of determining relative depth may not be possible in BMI experiments if movement control is more limited. Intuitive depth cues, such as including a virtual arm, can significantly improve depth perception accuracy with or without stereo viewing. PMID:18006069
Applications of just-noticeable depth difference model in joint multiview video plus depth coding
NASA Astrophysics Data System (ADS)
Liu, Chao; An, Ping; Zuo, Yifan; Zhang, Zhaoyang
2014-10-01
A new multiview just-noticeable-depth-difference(MJNDD) Model is presented and applied to compress the joint multiview video plus depth. Many video coding algorithms remove spatial and temporal redundancies and statistical redundancies but they are not capable of removing the perceptual redundancies. Since the final receptor of video is the human eyes, we can remove the perception redundancy to gain higher compression efficiency according to the properties of human visual system (HVS). Traditional just-noticeable-distortion (JND) model in pixel domain contains luminance contrast and spatial-temporal masking effects, which describes the perception redundancy quantitatively. Whereas HVS is very sensitive to depth information, a new multiview-just-noticeable-depth-difference(MJNDD) model is proposed by combining traditional JND model with just-noticeable-depth-difference (JNDD) model. The texture video is divided into background and foreground areas using depth information. Then different JND threshold values are assigned to these two parts. Later the MJNDD model is utilized to encode the texture video on JMVC. When encoding the depth video, JNDD model is applied to remove the block artifacts and protect the edges. Then we use VSRS3.5 (View Synthesis Reference Software) to generate the intermediate views. Experimental results show that our model can endure more noise and the compression efficiency is improved by 25.29 percent at average and by 54.06 percent at most compared to JMVC while maintaining the subject quality. Hence it can gain high compress ratio and low bit rate.
A Pursuit Theory Account for the Perception of Common Motion in Motion Parallax.
Ratzlaff, Michael; Nawrot, Mark
2016-09-01
The visual system uses an extraretinal pursuit eye movement signal to disambiguate the perception of depth from motion parallax. Visual motion in the same direction as the pursuit is perceived nearer in depth while visual motion in the opposite direction as pursuit is perceived farther in depth. This explanation of depth sign applies to either an allocentric frame of reference centered on the fixation point or an egocentric frame of reference centered on the observer. A related problem is that of depth order when two stimuli have a common direction of motion. The first psychophysical study determined whether perception of egocentric depth order is adequately explained by a model employing an allocentric framework, especially when the motion parallax stimuli have common rather than divergent motion. A second study determined whether a reversal in perceived depth order, produced by a reduction in pursuit velocity, is also explained by this model employing this allocentric framework. The results show than an allocentric model can explain both the egocentric perception of depth order with common motion and the perceptual depth order reversal created by a reduction in pursuit velocity. We conclude that an egocentric model is not the only explanation for perceived depth order in these common motion conditions. © The Author(s) 2016.
Reliability of a computer-based system for measuring visual performance skills.
Erickson, Graham B; Citek, Karl; Cove, Michelle; Wilczek, Jennifer; Linster, Carolyn; Bjarnason, Brendon; Langemo, Nathan
2011-09-01
Athletes have demonstrated better visual abilities than nonathletes. A vision assessment for an athlete should include methods to evaluate the quality of visual performance skills in the most appropriate, accurate, and repeatable manner. This study determines the reliability of the visual performance measures assessed with a computer-based system, known as the Nike Sensory Station. One hundred twenty-five subjects (56 men, 69 women), age 18 to 30, completed Phase I of the study. Subjects attended 2 sessions, separated by at least 1 week, in which identical protocols were followed. Subjects completed the following assessments: Visual Clarity, Contrast Sensitivity, Depth Perception, Near-Far Quickness, Target Capture, Perception Span, Eye-Hand Coordination, Go/No Go, and Reaction Time. An additional 36 subjects (20 men, 16 women), age 22 to 35, completed Phase II of the study involving modifications to the equipment, instructions, and protocols from Phase I. Results show no significant change in performance over time on assessments of Visual Clarity, Contrast Sensitivity, Depth Perception, Target Capture, Perception Span, and Reaction Time. Performance did improve over time for Near-Far Quickness, Eye-Hand Coordination, and Go/No Go. The results of this study show that many of the Nike Sensory Station assessments show repeatability and no learning effect over time. The measures that did improve across sessions show an expected learning effect caused by the motor response characteristics being measured. Copyright © 2011 American Optometric Association. Published by Elsevier Inc. All rights reserved.
Retinal fundus imaging with a plenoptic sensor
NASA Astrophysics Data System (ADS)
Thurin, Brice; Bloch, Edward; Nousias, Sotiris; Ourselin, Sebastien; Keane, Pearse; Bergeles, Christos
2018-02-01
Vitreoretinal surgery is moving towards 3D visualization of the surgical field. This require acquisition system capable of recording such 3D information. We propose a proof of concept imaging system based on a light-field camera where an array of micro-lenses is placed in front of a conventional sensor. With a single snapshot, a stack of images focused at different depth are produced on the fly, which provides enhanced depth perception for the surgeon. Difficulty in depth localization of features and frequent focus-change during surgery are making current vitreoretinal heads-up surgical imaging systems cumbersome to use. To improve the depth perception and eliminate the need to manually refocus on the instruments during the surgery, we designed and implemented a proof-of-concept ophthalmoscope equipped with a commercial light-field camera. The sensor of our camera is composed of an array of micro-lenses which are projecting an array of overlapped micro-images. We show that with a single light-field snapshot we can digitally refocus between the retina and a tool located in front of the retina or display an extended depth-of-field image where everything is in focus. The design and system performances of the plenoptic fundus camera are detailed. We will conclude by showing in vivo data recorded with our device.
Effects of cortical damage on binocular depth perception.
Bridge, Holly
2016-06-19
Stereoscopic depth perception requires considerable neural computation, including the initial correspondence of the two retinal images, comparison across the local regions of the visual field and integration with other cues to depth. The most common cause for loss of stereoscopic vision is amblyopia, in which one eye has failed to form an adequate input to the visual cortex, usually due to strabismus (deviating eye) or anisometropia. However, the significant cortical processing required to produce the percept of depth means that, even when the retinal input is intact from both eyes, brain damage or dysfunction can interfere with stereoscopic vision. In this review, I examine the evidence for impairment of binocular vision and depth perception that can result from insults to the brain, including both discrete damage, temporal lobectomy and more systemic diseases such as posterior cortical atrophy.This article is part of the themed issue 'Vision in our three-dimensional world'. © 2016 The Authors.
Effects of cortical damage on binocular depth perception
2016-01-01
Stereoscopic depth perception requires considerable neural computation, including the initial correspondence of the two retinal images, comparison across the local regions of the visual field and integration with other cues to depth. The most common cause for loss of stereoscopic vision is amblyopia, in which one eye has failed to form an adequate input to the visual cortex, usually due to strabismus (deviating eye) or anisometropia. However, the significant cortical processing required to produce the percept of depth means that, even when the retinal input is intact from both eyes, brain damage or dysfunction can interfere with stereoscopic vision. In this review, I examine the evidence for impairment of binocular vision and depth perception that can result from insults to the brain, including both discrete damage, temporal lobectomy and more systemic diseases such as posterior cortical atrophy. This article is part of the themed issue ‘Vision in our three-dimensional world’. PMID:27269597
Evaluating methods for controlling depth perception in stereoscopic cinematography
NASA Astrophysics Data System (ADS)
Sun, Geng; Holliman, Nick
2009-02-01
Existing stereoscopic imaging algorithms can create static stereoscopic images with perceived depth control function to ensure a compelling 3D viewing experience without visual discomfort. However, current algorithms do not normally support standard Cinematic Storytelling techniques. These techniques, such as object movement, camera motion, and zooming, can result in dynamic scene depth change within and between a series of frames (shots) in stereoscopic cinematography. In this study, we empirically evaluate the following three types of stereoscopic imaging approaches that aim to address this problem. (1) Real-Eye Configuration: set camera separation equal to the nominal human eye interpupillary distance. The perceived depth on the display is identical to the scene depth without any distortion. (2) Mapping Algorithm: map the scene depth to a predefined range on the display to avoid excessive perceived depth. A new method that dynamically adjusts the depth mapping from scene space to display space is presented in addition to an existing fixed depth mapping method. (3) Depth of Field Simulation: apply Depth of Field (DOF) blur effect to stereoscopic images. Only objects that are inside the DOF are viewed in full sharpness. Objects that are far away from the focus plane are blurred. We performed a human-based trial using the ITU-R BT.500-11 Recommendation to compare the depth quality of stereoscopic video sequences generated by the above-mentioned imaging methods. Our results indicate that viewers' practical 3D viewing volumes are different for individual stereoscopic displays and viewers can cope with much larger perceived depth range in viewing stereoscopic cinematography in comparison to static stereoscopic images. Our new dynamic depth mapping method does have an advantage over the fixed depth mapping method in controlling stereo depth perception. The DOF blur effect does not provide the expected improvement for perceived depth quality control in 3D cinematography. We anticipate the results will be of particular interest to 3D filmmaking and real time computer games.
Single-channel stereoscopic ophthalmology microscope based on TRD
NASA Astrophysics Data System (ADS)
Radfar, Edalat; Park, Jihoon; Lee, Sangyeob; Ha, Myungjin; Yu, Sungkon; Jang, Seulki; Jung, Byungjo
2016-03-01
A stereoscopic imaging modality was developed for the application of ophthalmology surgical microscopes. A previous study has already introduced a single-channel stereoscopic video imaging modality based on a transparent rotating deflector (SSVIM-TRD), in which two different view angles, image disparity, are generated by imaging through a transparent rotating deflector (TRD) mounted on a stepping motor and is placed in a lens system. In this case, the image disparity is a function of the refractive index and the rotation angle of TRD. Real-time single-channel stereoscopic ophthalmology microscope (SSOM) based on the TRD is improved by real-time controlling and programming, imaging speed, and illumination method. Image quality assessments were performed to investigate images quality and stability during the TRD operation. Results presented little significant difference in image quality in terms of stability of structural similarity (SSIM). A subjective analysis was performed with 15 blinded observers to evaluate the depth perception improvement and presented significant improvement in the depth perception capability. Along with all evaluation results, preliminary results of rabbit eye imaging presented that the SSOM could be utilized as an ophthalmic operating microscopes to overcome some of the limitations of conventional ones.
Finucane, Melissa L; Nghiem, Tuyen; Saksena, Sumeet; Nguyen, Lam; Fox, Jefferson; Spencer, James H; Thau, Trinh Dinh
2014-01-01
This research examined how perceptions of outbreaks of highly pathogenic avian influenza (HPAI) subtype H5N1 in poultry are related to urbanization. Via in-depth interviews with village leaders, household farmers, and large farm operators in modern, transitional, and traditional communes in the north of Vietnam, we explored behaviors, attitudes, cultural values, and traditions that might amplify or attenuate HPAI outbreaks. We also explored conceptualizations of urbanization and its impacts on animal husbandry and disease outbreaks. Qualitative theme analyses identified the key impacts, factors related to HPAI outbreaks, and disease prevention and management strategies. The analyses also highlighted how urbanization improves some aspects of life (e.g., food security, family wealth and health, more employment opportunities, and improved infrastructure), but simultaneously poses significant challenges for poultry farming and disease management. Awareness of qualitative aspects of HPAI risk perceptions and behaviors and how they vary with urbanization processes may help to improve the prevention and management of emerging infectious diseases.
Clinically Normal Stereopsis Does Not Ensure Performance Benefit from Stereoscopic 3D Depth Cues
2014-10-28
Stereopsis, Binocular Vision, Optometry , Depth Perception, 3D vision, 3D human factors, Stereoscopic displays, S3D, Virtual environment 16...Binocular Vision, Optometry , Depth Perception, 3D vision, 3D human factors, Stereoscopic displays, S3D, Virtual environment 1 Distribution A: Approved
Gestalt grouping via closure degrades suprathreshold depth percepts.
Deas, Lesley M; Wilcox, Laurie M
2014-08-19
It is well known that the perception of depth is susceptible to changes in configuration. For example, stereoscopic precision for a pair of vertical lines can be dramatically reduced when these lines are connected to form a closed object. Here, we extend this paradigm to suprathreshold estimates of perceived depth. Using a touch-sensor, observers made quantitative estimates of depth between a vertical line pair presented in isolation or as edges of a closed rectangular object with different figural interpretations. First, we show that the amount of depth estimated within a closed rectangular object is consistently reduced relative to the vertical edges presented in isolation or when they form the edges of two segmented objects. We then demonstrate that the reduction in perceived depth for closed objects is modulated by manipulations that influence perceived closure of the central figure. Depth percepts were most disrupted when the horizontal connectors and vertical lines matched in color. Perceived depth increased slightly when the connectors had opposite contrast polarity, but increased dramatically when flankers were added. Thus, as grouping cues were added to counter the interpretation of a closed object, the depth degradation effect was systematically eliminated. The configurations tested here rule out explanations based on early, local interactions such as inhibition or cue conflict; instead, our results provide strong evidence of the impact of Gestalt grouping, via closure, on depth magnitude percepts from stereopsis. © 2014 ARVO.
The perception of depth from binocular disparity.
DOT National Transportation Integrated Search
1963-05-01
This study was concerned with the factors involved in the perception of depth from a binocular disparity. A binocularly observed configuration of constant convergences, constant visual size, and having constant binocular disparities was made to appea...
Perceptual Calibration for Immersive Display Environments
Ponto, Kevin; Gleicher, Michael; Radwin, Robert G.; Shin, Hyun Joon
2013-01-01
The perception of objects, depth, and distance has been repeatedly shown to be divergent between virtual and physical environments. We hypothesize that many of these discrepancies stem from incorrect geometric viewing parameters, specifically that physical measurements of eye position are insufficiently precise to provide proper viewing parameters. In this paper, we introduce a perceptual calibration procedure derived from geometric models. While most research has used geometric models to predict perceptual errors, we instead use these models inversely to determine perceptually correct viewing parameters. We study the advantages of these new psychophysically determined viewing parameters compared to the commonly used measured viewing parameters in an experiment with 20 subjects. The perceptually calibrated viewing parameters for the subjects generally produced new virtual eye positions that were wider and deeper than standard practices would estimate. Our study shows that perceptually calibrated viewing parameters can significantly improve depth acuity, distance estimation, and the perception of shape. PMID:23428454
Orr, Elizabeth M J; Moscovitch, David A
2010-08-01
Video feedback (VF) with cognitive preparation (CP) has been widely integrated into cognitive-behavioral therapy (CBT) protocols for social anxiety disorder (SAD) due to its presumed efficacy in improving negative self-perception. However, previous experimental studies have demonstrated that improvements in negative self-perception via VF+CP do not typically facilitate anxiety reduction during subsequent social interactions - a troubling finding for proponents of cognitive models of social anxiety. We examined whether VF+CP could be optimized to enhance participants' processing of corrective self-related information through the addition of a post-VF cognitive review (CR). Sixty-eight socially anxious individuals were randomly assigned to perform two public speeches in one of the following conditions: a) exposure alone (EXP); b) CP+VF; and c) CP+VF+CR. Those in the CP+VF+CR condition demonstrated marginally significant reductions in anxiety from speech 1 to speech 2 relative to those who received EXP - an improvement not shown for those in the CP+VF condition. Furthermore, only those who received CP+VF+CR demonstrated significant improvements in self-perception and performance expectations relative to EXP. Decreases in anxiety among participants who received CP+VF+CR relative to EXP were fully mediated by improvements in self-perception. Implications are discussed in the context of cognitive models of social anxiety and mechanisms of exposure-based learning. Copyright 2010 Elsevier Ltd. All rights reserved.
Real-time multiple human perception with color-depth cameras on a mobile robot.
Zhang, Hao; Reardon, Christopher; Parker, Lynne E
2013-10-01
The ability to perceive humans is an essential requirement for safe and efficient human-robot interaction. In real-world applications, the need for a robot to interact in real time with multiple humans in a dynamic, 3-D environment presents a significant challenge. The recent availability of commercial color-depth cameras allow for the creation of a system that makes use of the depth dimension, thus enabling a robot to observe its environment and perceive in the 3-D space. Here we present a system for 3-D multiple human perception in real time from a moving robot equipped with a color-depth camera and a consumer-grade computer. Our approach reduces computation time to achieve real-time performance through a unique combination of new ideas and established techniques. We remove the ground and ceiling planes from the 3-D point cloud input to separate candidate point clusters. We introduce the novel information concept, depth of interest, which we use to identify candidates for detection, and that avoids the computationally expensive scanning-window methods of other approaches. We utilize a cascade of detectors to distinguish humans from objects, in which we make intelligent reuse of intermediary features in successive detectors to improve computation. Because of the high computational cost of some methods, we represent our candidate tracking algorithm with a decision directed acyclic graph, which allows us to use the most computationally intense techniques only where necessary. We detail the successful implementation of our novel approach on a mobile robot and examine its performance in scenarios with real-world challenges, including occlusion, robot motion, nonupright humans, humans leaving and reentering the field of view (i.e., the reidentification challenge), human-object and human-human interaction. We conclude with the observation that the incorporation of the depth information, together with the use of modern techniques in new ways, we are able to create an accurate system for real-time 3-D perception of humans by a mobile robot.
Benefits and Barriers of Pediatric Healthcare Providers toward Using Social Media in Asthma Care
ERIC Educational Resources Information Center
Martinasek, Mary P.; Panzera, Anthony D.; Schneider, Tali; Lindenberger, James H.; Bryant, Carol A.; McDermott, Robert J.; Couluris, Marisa
2011-01-01
Background: Adolescents with asthma are the least compliant age group for asthma management. Purpose: The purpose of this study was to explore attitudes, beliefs and perceptions of two pediatric physician groups towards using social media technology (SMT) to improve asthma management in adolescents. Methods: We employed in-depth interviews and a…
Educational Applications of Vision Therapy: A Pilot Study on Children with Autism.
ERIC Educational Resources Information Center
Lovelace, Kelly; Rhodes, Heidi; Chambliss, Catherine
This report discusses the outcomes of a study that explored the feasibility of using vision therapy (VT) as part of an interdisciplinary approach to the education of children with autism. Traditional research on VT has explored its usefulness in helping patients to use both eyes together, improve depth perception, and enhance visual acuity.…
Improving Scores on Computerized Reading Assessments: The Effects of Colored Overlay Use
ERIC Educational Resources Information Center
Adams, Tracy A.
2012-01-01
Visual stress is a perceptual dysfunction that appears to affect how information is processed as it passes from the eyes to the brain. Photophobia, visual resolution, restricted focus, sustaining focus, and depth perception are all components of visual stress. Because visual stress affects what is perceived by the eye, students with this disorder…
Challenges of Blended E-Learning Tools in Mathematics: Students' Perspectives University of Uyo
ERIC Educational Resources Information Center
Umoh, Joseph B.; Akpan, Ekemini T.
2014-01-01
An in-depth knowledge of pedagogical approaches can help improve the formulation of effective and efficient pedagogy, tools and technology to support and enhance the teaching and learning of Mathematics in higher institutions. This study investigated students' perceptions of the challenges of blended e-learning tools in the teaching and learning…
Long-Duration Spaceflight Increases Depth Ambiguity of Reversible Perspective Figures.
Clément, Gilles; Allaway, Heather C M; Demel, Michael; Golemis, Adrianos; Kindrat, Alexandra N; Melinyshyn, Alexander N; Merali, Tahir; Thirsk, Robert
2015-01-01
The objective of this study was to investigate depth perception in astronauts during and after spaceflight by studying their sensitivity to reversible perspective figures in which two-dimensional images could elicit two possible depth representations. Other ambiguous figures that did not give rise to a perception of illusory depth were used as controls. Six astronauts and 14 subjects were tested in the laboratory during three sessions for evaluating the variability of their responses in normal gravity. The six astronauts were then tested during four sessions while on board the International Space Station for 5-6 months. They were finally tested immediately after return to Earth and up to one week later. The reaction time decreased throughout the sessions, thus indicating a learning effect. However, the time to first percept reversal and the number of reversals were not different in orbit and after the flight compared to before the flight. On Earth, when watching depth-ambiguous perspective figures, all subjects reported seeing one three-dimensional interpretation more often than the other, i.e. a ratio of about 70-30%. In weightlessness this asymmetry gradually disappeared and after 3 months in orbit both interpretations were seen for the same duration. These results indicate that the perception of "illusory" depth is altered in astronauts during spaceflight. This increased depth ambiguity is attributed to the lack of the gravitational reference and the eye-ground elevation for interpreting perspective depth cues.
The (In)Effectiveness of Simulated Blur for Depth Perception in Naturalistic Images.
Maiello, Guido; Chessa, Manuela; Solari, Fabio; Bex, Peter J
2015-01-01
We examine depth perception in images of real scenes with naturalistic variation in pictorial depth cues, simulated dioptric blur and binocular disparity. Light field photographs of natural scenes were taken with a Lytro plenoptic camera that simultaneously captures images at up to 12 focal planes. When accommodation at any given plane was simulated, the corresponding defocus blur at other depth planes was extracted from the stack of focal plane images. Depth information from pictorial cues, relative blur and stereoscopic disparity was separately introduced into the images. In 2AFC tasks, observers were required to indicate which of two patches extracted from these images was farther. Depth discrimination sensitivity was highest when geometric and stereoscopic disparity cues were both present. Blur cues impaired sensitivity by reducing the contrast of geometric information at high spatial frequencies. While simulated generic blur may not assist depth perception, it remains possible that dioptric blur from the optics of an observer's own eyes may be used to recover depth information on an individual basis. The implications of our findings for virtual reality rendering technology are discussed.
The (In)Effectiveness of Simulated Blur for Depth Perception in Naturalistic Images
Maiello, Guido; Chessa, Manuela; Solari, Fabio; Bex, Peter J.
2015-01-01
We examine depth perception in images of real scenes with naturalistic variation in pictorial depth cues, simulated dioptric blur and binocular disparity. Light field photographs of natural scenes were taken with a Lytro plenoptic camera that simultaneously captures images at up to 12 focal planes. When accommodation at any given plane was simulated, the corresponding defocus blur at other depth planes was extracted from the stack of focal plane images. Depth information from pictorial cues, relative blur and stereoscopic disparity was separately introduced into the images. In 2AFC tasks, observers were required to indicate which of two patches extracted from these images was farther. Depth discrimination sensitivity was highest when geometric and stereoscopic disparity cues were both present. Blur cues impaired sensitivity by reducing the contrast of geometric information at high spatial frequencies. While simulated generic blur may not assist depth perception, it remains possible that dioptric blur from the optics of an observer’s own eyes may be used to recover depth information on an individual basis. The implications of our findings for virtual reality rendering technology are discussed. PMID:26447793
van der Jagt, M Annerie; Briaire, Jeroen J; Verbist, Berit M; Frijns, Johan H M
2016-01-01
The HiFocus Mid-Scala (MS) electrode array has recently been introduced onto the market. This precurved design with a targeted mid-scalar intracochlear position pursues an atraumatic insertion and optimal distance for neural stimulation. In this study we prospectively examined the angular insertion depth achieved and speech perception outcomes resulting from the HiFocus MS electrode array for 6 months after implantation, and retrospectively compared these with the HiFocus 1J lateral wall electrode array. The mean angular insertion depth within the MS population (n = 96) was found at 470°. This was 50° shallower but more consistent than the 1J electrode array (n = 110). Audiological evaluation within a subgroup, including only postlingual, unilaterally implanted, adult cochlear implant recipients who were matched on preoperative speech perception scores and the duration of deafness (MS = 32, 1J = 32), showed no difference in speech perception outcomes between the MS and 1J groups. Furthermore, speech perception outcome was not affected by the angular insertion depth or frequency mismatch. © 2016 S. Karger AG, Basel.
NASA Astrophysics Data System (ADS)
Ando, Yoriko; Sawahata, Hirohito; Kawano, Takeshi; Koida, Kowa; Numano, Rika
2018-02-01
Bundled fiber optics allow in vivo imaging at deep sites in a body. The intrinsic optical contrast detects detailed structures in blood vessels and organs. We developed a bundled-fiber-coupled endomicroscope, enabling stereoscopic three-dimensional (3-D) reflectance imaging with a multipositional illumination scheme. Two illumination sites were attached to obtain reflectance images with left and right illumination. Depth was estimated by the horizontal disparity between the two images under alternative illuminations and was calibrated by the targets with known depths. This depth reconstruction was applied to an animal model to obtain the 3-D structure of blood vessels of the cerebral cortex (Cereb cortex) and preputial gland (Pre gla). The 3-D endomicroscope could be instrumental to microlevel reflectance imaging, improving the precision in subjective depth perception, spatial orientation, and identification of anatomical structures.
Depth Perception In Remote Stereoscopic Viewing Systems
NASA Technical Reports Server (NTRS)
Diner, Daniel B.; Von Sydow, Marika
1989-01-01
Report describes theoretical and experimental studies of perception of depth by human operators through stereoscopic video systems. Purpose of such studies to optimize dual-camera configurations used to view workspaces of remote manipulators at distances of 1 to 3 m from cameras. According to analysis, static stereoscopic depth distortion decreased, without decreasing stereoscopitc depth resolution, by increasing camera-to-object and intercamera distances and camera focal length. Further predicts dynamic stereoscopic depth distortion reduced by rotating cameras around center of circle passing through point of convergence of viewing axes and first nodal points of two camera lenses.
Long-Duration Spaceflight Increases Depth Ambiguity of Reversible Perspective Figures
Clément, Gilles; Allaway, Heather C. M.; Demel, Michael; Golemis, Adrianos; Kindrat, Alexandra N.; Melinyshyn, Alexander N.; Merali, Tahir; Thirsk, Robert
2015-01-01
The objective of this study was to investigate depth perception in astronauts during and after spaceflight by studying their sensitivity to reversible perspective figures in which two-dimensional images could elicit two possible depth representations. Other ambiguous figures that did not give rise to a perception of illusory depth were used as controls. Six astronauts and 14 subjects were tested in the laboratory during three sessions for evaluating the variability of their responses in normal gravity. The six astronauts were then tested during four sessions while on board the International Space Station for 5–6 months. They were finally tested immediately after return to Earth and up to one week later. The reaction time decreased throughout the sessions, thus indicating a learning effect. However, the time to first percept reversal and the number of reversals were not different in orbit and after the flight compared to before the flight. On Earth, when watching depth-ambiguous perspective figures, all subjects reported seeing one three-dimensional interpretation more often than the other, i.e. a ratio of about 70–30%. In weightlessness this asymmetry gradually disappeared and after 3 months in orbit both interpretations were seen for the same duration. These results indicate that the perception of “illusory” depth is altered in astronauts during spaceflight. This increased depth ambiguity is attributed to the lack of the gravitational reference and the eye-ground elevation for interpreting perspective depth cues. PMID:26146839
3D Visualizations of Abstract DataSets
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
Human Stereopsis is not Limited by the Optics of the Well-focused Eye
Vlaskamp, Björn N.S.; Yoon, Geunyoung; Banks, Martin S.
2011-01-01
Human stereopsis—the perception of depth from differences in the two eyes’ images—is very precise: Image differences smaller than a single photoreceptor can be converted into a perceived difference in depth. To better understand what determines this precision, we examined how the eyes’ optics affects stereo resolution. We did this by comparing performance with normal, well-focused optics and with optics improved by eliminating chromatic aberration and correcting higher-order aberrations. We first measured luminance contrast sensitivity in both eyes and showed that we had indeed improved optical quality significantly. We then measured stereo resolution in two ways: by finding the finest corrugation in depth that one can perceive, and by finding the smallest disparity one can perceive as different from zero. Our optical manipulation had no effect on stereo performance. We checked this by redoing the experiments at low contrast and again found no effect of improving optical quality. Thus, the resolution of human stereopsis is not limited by the optics of the well-focused eye. We discuss the implications of this remarkable finding. PMID:21734272
Stereoscopic perception of real depths at large distances.
Palmisano, Stephen; Gillam, Barbara; Govan, Donovan G; Allison, Robert S; Harris, Julie M
2010-06-01
There has been no direct examination of stereoscopic depth perception at very large observation distances and depths. We measured perceptions of depth magnitude at distances where it is frequently reported without evidence that stereopsis is non-functional. We adapted methods pioneered at distances up to 9 m by R. S. Allison, B. J. Gillam, and E. Vecellio (2009) for use in a 381-m-long railway tunnel. Pairs of Light Emitting Diode (LED) targets were presented either in complete darkness or with the environment lit as far as the nearest LED (the observation distance). We found that binocular, but not monocular, estimates of the depth between pairs of LEDs increased with their physical depths up to the maximum depth separation tested (248 m). Binocular estimates of depth were much larger with a lit foreground than in darkness and increased as the observation distance increased from 20 to 40 m, indicating that binocular disparity can be scaled for much larger distances than previously realized. Since these observation distances were well beyond the range of vertical disparity and oculomotor cues, this scaling must rely on perspective cues. We also ran control experiments at smaller distances, which showed that estimates of depth and distance correlate poorly and that our metric estimation method gives similar results to a comparison method under the same conditions.
NASA Astrophysics Data System (ADS)
Bennett, Sean T.
This study examines African American student perceptions of persistence in engineering. The research design is methodologically qualitative using a purposefully selected population of engineering students. Semi-structured interviews were designed to develop an in-depth understanding of what completion of the engineering degree means to African American engineering students. This research seeks insight into the linkages between African American student perceptions of persistence as it relates to both the academic and social culture of the engineering department. Vincent Tinto's model of Institutional Departure (1975, 1987) is one of the most commonly cited models of persistence in higher education (Braxton, Milem, Sullivan, 2000). Tinto's model was leveraged in this study to understand perceptions obtained through student interviews. Tinto suggests that exploration of student goal commitment and perceptions of institutional commitment are key to understanding student persistence. Results of this study suggest that African American students have perceptions about the university that may influence the decision to persist in engineering. Ultimately, this study may prove useful to researchers and administrators interested in improving access and success for African American engineering students.
ERIC Educational Resources Information Center
Long, Barbara Ellis
1974-01-01
Tests the hypothesis that teachers can learn about and use a psychological curriculum without extensive prior study of psychology, and that students will show gain in depth of self-perception and higher levels of psychological maturity. (Author/RP)
Visual risk factors for falls in older people.
Lord, Stephen R
2006-09-01
Poor vision reduces postural stability and significantly increases the risk of falls and fractures in older people. Most studies have found that poor visual acuity increases the risk of falls. However, studies that have included multiple visual measures have found that reduced contrast sensitivity and depth perception are the most important visual risk factors for falls. Multifocal glasses may add to this risk because their near-vision lenses impair distance contrast sensitivity and depth perception in the lower visual field. This reduces the ability of an older person to detect environmental hazards. There is now evidence that maximising vision through cataract surgery is an effective strategy for preventing falls. Further randomised controlled trials are required to determine whether individual strategies (such as restriction of use of multifocal glasses) or multi-strategy visual improvement interventions can significantly reduce falls in older people. Public health initiatives are required to raise awareness in older people and their carers of the importance of regular eye examinations and use of appropriate prescription glasses.
The facing bias in biological motion perception: structure, kinematics, and body parts.
Schouten, Ben; Troje, Nikolaus F; Verfaillie, Karl
2011-01-01
Depth-ambiguous point-light walkers (PLWs) elicit a facing bias: Observers perceive a PLW as facing toward them more often than as facing away (Vanrie,Dekeyser, & Verfaillie, Perception, 33, 547-560, 2004). While the facing bias correlates with the PLW's perceived gender (Brooks et al., Current Biology, 18, R728-R729, 2008; Schouten, Troje, Brooks, van der Zwan, & Verfaillie, Attention, Perception, & Psychophysics, 72,1256-1260, 2010), it remains unclear whether the change in perceived in-depth orientation is caused by a change in perceived gender. In Experiment 1, we show that structural and kinematic stimulus properties that lead to the same changes in perceived gender elicit opposite changes in perceived in-depth orientation, indicating that the relation between perceived gender and in-depth orientation is not causal. The results of Experiments 2 and 3 further suggest that the perceived in-depth orientation of PLWs is strongly affected by locally acting stimulus properties. The facing bias seems to be induced by stimulus properties in the lower part of the PLW.
Activation of the Human MT Complex by Motion in Depth Induced by a Moving Cast Shadow
Katsuyama, Narumi; Usui, Nobuo; Taira, Masato
2016-01-01
A moving cast shadow is a powerful monocular depth cue for motion perception in depth. For example, when a cast shadow moves away from or toward an object in a two-dimensional plane, the object appears to move toward or away from the observer in depth, respectively, whereas the size and position of the object are constant. Although the cortical mechanisms underlying motion perception in depth by cast shadow are unknown, the human MT complex (hMT+) is likely involved in the process, as it is sensitive to motion in depth represented by binocular depth cues. In the present study, we examined this possibility by using a functional magnetic resonance imaging (fMRI) technique. First, we identified the cortical regions sensitive to the motion of a square in depth represented via binocular disparity. Consistent with previous studies, we observed significant activation in the bilateral hMT+, and defined functional regions of interest (ROIs) there. We then investigated the activity of the ROIs during observation of the following stimuli: 1) a central square that appeared to move back and forth via a moving cast shadow (mCS); 2) a segmented and scrambled cast shadow presented beside the square (sCS); and 3) no cast shadow (nCS). Participants perceived motion of the square in depth in the mCS condition only. The activity of the hMT+ was significantly higher in the mCS compared with the sCS and nCS conditions. Moreover, the hMT+ was activated equally in both hemispheres in the mCS condition, despite presentation of the cast shadow in the bottom-right quadrant of the stimulus. Perception of the square moving in depth across visual hemifields may be reflected in the bilateral activation of the hMT+. We concluded that the hMT+ is involved in motion perception in depth induced by moving cast shadow and by binocular disparity. PMID:27597999
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.
Finlayson, Nonie J.; Golomb, Julie D.
2016-01-01
A fundamental aspect of human visual perception is the ability to recognize and locate objects in the environment. Importantly, our environment is predominantly three-dimensional (3D), but while there is considerable research exploring the binding of object features and location, it is unknown how depth information interacts with features in the object binding process. A recent paradigm called the spatial congruency bias demonstrated that 2D location is fundamentally bound to object features (Golomb, Kupitz, & Thiemann, 2014), such that irrelevant location information biases judgments of object features, but irrelevant feature information does not bias judgments of location or other features. Here, using the spatial congruency bias paradigm, we asked whether depth is processed as another type of location, or more like other features. We initially found that depth cued by binocular disparity biased judgments of object color. However, this result seemed to be driven more by the disparity differences than the depth percept: Depth cued by occlusion and size did not bias color judgments, whereas vertical disparity information (with no depth percept) did bias color judgments. Our results suggest that despite the 3D nature of our visual environment, only 2D location information – not position-in-depth – seems to be automatically bound to object features, with depth information processed more similarly to other features than to 2D location. PMID:27468654
Finlayson, Nonie J; Golomb, Julie D
2016-10-01
A fundamental aspect of human visual perception is the ability to recognize and locate objects in the environment. Importantly, our environment is predominantly three-dimensional (3D), but while there is considerable research exploring the binding of object features and location, it is unknown how depth information interacts with features in the object binding process. A recent paradigm called the spatial congruency bias demonstrated that 2D location is fundamentally bound to object features, such that irrelevant location information biases judgments of object features, but irrelevant feature information does not bias judgments of location or other features. Here, using the spatial congruency bias paradigm, we asked whether depth is processed as another type of location, or more like other features. We initially found that depth cued by binocular disparity biased judgments of object color. However, this result seemed to be driven more by the disparity differences than the depth percept: Depth cued by occlusion and size did not bias color judgments, whereas vertical disparity information (with no depth percept) did bias color judgments. Our results suggest that despite the 3D nature of our visual environment, only 2D location information - not position-in-depth - seems to be automatically bound to object features, with depth information processed more similarly to other features than to 2D location. Copyright © 2016 Elsevier Ltd. All rights reserved.
Influence of visual path information on human heading perception during rotation.
Li, Li; Chen, Jing; Peng, Xiaozhe
2009-03-31
How does visual path information influence people's perception of their instantaneous direction of self-motion (heading)? We have previously shown that humans can perceive heading without direct access to visual path information. Here we vary two key parameters for estimating heading from optic flow, the field of view (FOV) and the depth range of environmental points, to investigate the conditions under which visual path information influences human heading perception. The display simulated an observer traveling on a circular path. Observers used a joystick to rotate their line of sight until deemed aligned with true heading. Four FOV sizes (110 x 94 degrees, 48 x 41 degrees, 16 x 14 degrees, 8 x 7 degrees) and depth ranges (6-50 m, 6-25 m, 6-12.5 m, 6-9 m) were tested. Consistent with our computational modeling results, heading bias increased with the reduction of FOV or depth range when the display provided a sequence of velocity fields but no direct path information. When the display provided path information, heading bias was not influenced as much by the reduction of FOV or depth range. We conclude that human heading and path perception involve separate visual processes. Path helps heading perception when the display does not contain enough optic-flow information for heading estimation during rotation.
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.
NASA Astrophysics Data System (ADS)
Wilder, Sharon Mae
This naturalistic study focused on the perceptions of leadership and student performance in science from campus leaders in three purposefully selected secondary campuses of ninth through twelfth grades. Each school had experienced an improvement in student passing rates on the science TAKS test that exceeded the state's percent improvement in passing rates for the past three years and had a record of improving science TAKS scores for the period of 2003 to 2008 exceeding fifteen percentage points. The qualitative research technique of multi-case studies design was used. Data was collected through semi-structured, in-depth interviews with four campus leaders from each of the selected schools. These campus leaders included campus administrators, science department chairs, and grade-level team leaders. A framework of transformational leadership was utilized in the analysis of the data generated from the interviews. The perception from the campus leaders was that leadership has a positive impact on student success in science. The findings indicated perceptions of leadership from the campus leaders had certain leadership practices in common. These included (a) clear vision and goals from the campus principal, (b) high performance expectations for teachers and students from administrators and science department leaders, (c) encouragement and support from campus administrators and science department leaders to develop new programs to address problem areas, (d) emphasis on collaborative teams, and (e) open door policy from administrators.
Ting, Xu; Yong, Bao; Yin, Liang; Mi, Tian
2016-03-01
To investigate patient perceptions of patient-centered communication (PCC) in doctor-patient consultations and explore barriers to PCC implementation in China. This study was conducted in public teaching hospital in Guiyang, Guizhou, China. In Phase 1, patient attitudes to PCC were quantitatively assessed in 317 outpatients using modified Patient-Practitioner Orientation Scale (PPOS). In Phase 2, we conducted in-depth interviews with 20 outpatients to explore their views on PCC and expose potential barriers to PCC implementation. Participants communicated "patient-centered" preferences, particularly with regard to their doctors' empathy, communication skills, time and information sharing. Patients were more concerned about doctors exhibiting caring perspective than power sharing. Younger and highly educated patients were more likely to prefer PCC and highly educated patients paid more attention to power sharing. Several factors including inadequate time for PCC resulting from doctors' high patient-load, doctor-patient communication difficulties and excessive treatment due to inappropriate medical payment system affected PCC implementation in China. Patients expressed moderate enthusiasm for PCC in China. They expressed strong preferences concerning physician respect for patient perspective, but less concern for power sharing. Government should improve health care system by implementing PCC in daily healthcare practice to improve patient awareness and preferences. Copyright © 2016. Published by Elsevier Ireland Ltd.
Hale, Leigh A; Satherley, Jessica A; McMillan, Nicole J; Milosavljevic, Stephan; Hijmans, Juha M; King, Marcus J
2012-01-01
This article reports on the perceptions of 14 adults with chronic stroke who participated in a pilot study to determine the utility, acceptability, and potential efficacy of using an adapted CyWee Z handheld game controller to play a variety of computer games aimed at improving upper-limb function. Four qualitative in-depth interviews and two focus groups explored participant perceptions. Data were thematically analyzed with the general inductive approach. Participants enjoyed playing the computer games with the technology. The perceived benefits included improved upper-limb function, concentration, and balance; however, six participants reported shoulder and/or arm pain or discomfort, which presented while they were engaged in play but appeared to ease during rest. Participants suggested changes to the games and provided opinions on the use of computer games in rehabilitation. Using an adapted CyWee Z controller and computer games in upper-limb rehabilitation for people with chronic stroke is an acceptable and potentially beneficial adjunct to rehabilitation. The development of shoulder pain was a negative side effect for some participants and requires further investigation.
te Woerd, Erik S.; Oostenveld, Robert; Bloem, Bastiaan R.; de Lange, Floris P.; Praamstra, Peter
2015-01-01
The basal ganglia play an important role in beat perception and patients with Parkinson’s disease (PD) are impaired in perception of beat-based rhythms. Rhythmic cues are nonetheless beneficial in gait rehabilitation, raising the question how rhythm improves movement in PD. We addressed this question with magnetoencephalography recordings during a choice response task with rhythmic and non-rhythmic modes of stimulus presentation. Analyses focused on (i) entrainment of slow oscillations, (ii) the depth of beta power modulation, and (iii) whether a gain in modulation depth of beta power, due to rhythmicity, is of predictive or reactive nature. The results show weaker phase synchronisation of slow oscillations and a relative shift from predictive to reactive movement-related beta suppression in PD. Nonetheless, rhythmic stimulus presentation increased beta modulation depth to the same extent in patients and controls. Critically, this gain selectively increased the predictive and not reactive movement-related beta power suppression. Operation of a predictive mechanism, induced by rhythmic stimulation, was corroborated by a sensory gating effect in the sensorimotor cortex. The predictive mode of cue utilisation points to facilitation of basal ganglia-premotor interactions, contrasting with the popular view that rhythmic stimulation confers a special advantage in PD, based on recruitment of alternative pathways. PMID:26509117
Monocular zones in stereoscopic scenes: A useful source of information for human binocular vision?
NASA Astrophysics Data System (ADS)
Harris, Julie M.
2010-02-01
When an object is closer to an observer than the background, the small differences between right and left eye views are interpreted by the human brain as depth. This basic ability of the human visual system, called stereopsis, lies at the core of all binocular three-dimensional (3-D) perception and related technological display development. To achieve stereopsis, it is traditionally assumed that corresponding locations in the right and left eye's views must first be matched, then the relative differences between right and left eye locations are used to calculate depth. But this is not the whole story. At every object-background boundary, there are regions of the background that only one eye can see because, in the other eye's view, the foreground object occludes that region of background. Such monocular zones do not have a corresponding match in the other eye's view and can thus cause problems for depth extraction algorithms. In this paper I will discuss evidence, from our knowledge of human visual perception, illustrating that monocular zones do not pose problems for our human visual systems, rather, our visual systems can extract depth from such zones. I review the relevant human perception literature in this area, and show some recent data aimed at quantifying the perception of depth from monocular zones. The paper finishes with a discussion of the potential importance of considering monocular zones, for stereo display technology and depth compression algorithms.
NASA Astrophysics Data System (ADS)
Bouma, Henri; van der Mark, Wannes; Eendebak, Pieter T.; Landsmeer, Sander H.; van Eekeren, Adam W. M.; ter Haar, Frank B.; Wieringa, F. Pieter; van Basten, Jean-Paul
2012-06-01
Compared to open surgery, minimal invasive surgery offers reduced trauma and faster recovery. However, lack of direct view limits space perception. Stereo-endoscopy improves depth perception, but is still restricted to the direct endoscopic field-of-view. We describe a novel technology that reconstructs 3D-panoramas from endoscopic video streams providing a much wider cumulative overview. The method is compatible with any endoscope. We demonstrate that it is possible to generate photorealistic 3D-environments from mono- and stereoscopic endoscopy. The resulting 3D-reconstructions can be directly applied in simulators and e-learning. Extended to real-time processing, the method looks promising for telesurgery or other remote vision-guided tasks.
Laisser, Rose M; Lugina, Helen I; Lindmark, Gunilla; Nystrom, Lennarth; Emmelin, Maria
2009-01-01
In this article we describe health care workers' (HCWs') experiences and perceptions of meeting clients exposed to intimate partner violence (IPV). Qualitative content analysis of in-depth interviews from 16 informants resulted in four main themes. The first, "internalizing women's suffering and powerlessness," describes HCWs' perceptions of violence, relating it to gender relations. The second, "caught between encouraging disclosure and lack of support tools," refers to views on possibilities for transparency and openness. The third, "Why bother? A struggle to manage with limited resources," illustrates the consequences of a heavy workload. Last; "striving to make a difference," emphasizes a desire to improve abilities to support clients and advocate for prevention.
Method and simulation to study 3D crosstalk perception
NASA Astrophysics Data System (ADS)
Khaustova, Dar'ya; Blondé, Laurent; Huynh-Thu, Quan; Vienne, Cyril; Doyen, Didier
2012-03-01
To various degrees, all modern 3DTV displays suffer from crosstalk, which can lead to a decrease of both visual quality and visual comfort, and also affect perception of depth. In the absence of a perfect 3D display technology, crosstalk has to be taken into account when studying perception of 3D stereoscopic content. In order to improve 3D presentation systems and understand how to efficiently eliminate crosstalk, it is necessary to understand its impact on human perception. In this paper, we present a practical method to study the perception of crosstalk. The approach consists of four steps: (1) physical measurements of a 3DTV, (2) building of a crosstalk surface based on those measurements and representing specifically the behavior of that 3TV, (3) manipulation of the crosstalk function and application on reference images to produce test images degraded by crosstalk in various ways, and (4) psychophysical tests. Our approach allows both a realistic representation of the behavior of a 3DTV and the easy manipulation of its resulting crosstalk in order to conduct psycho-visual experiments. Our approach can be used in all studies requiring the understanding of how crosstalk affects perception of stereoscopic content and how it can be corrected efficiently.
The effects of quantity and depth of processing on children's time perception.
Arlin, M
1986-08-01
Two experiments were conducted to investigate the effects of quantity and depth of processing on children's time perception. These experiments tested the appropriateness of two adult time-perception models (attentional and storage size) for younger ages. Children were given stimulus sets of equal time which varied by level of processing (deep/shallow) and quantity (list length). In the first experiment, 28 children in Grade 6 reproduced presentation times of various quantities of pictures under deep (living/nonliving categorization) or shallow (repeating label) conditions. Students also compared pairs of durations. In the second experiment, 128 children in Grades K, 2, 4, and 6 reproduced presentation times under similar conditions with three or six pictures and with deep or shallow processing requirements. Deep processing led to decreased estimation of time. Higher quantity led to increased estimation of time. Comparative judgments were influenced by quantity. The interaction between age and depth of processing was significant. Older children were more affected by depth differences than were younger children. Results were interpreted as supporting different aspects of each adult model as explanations of children's time perception. The processing effect supported the attentional model and the quantity effect supported the storage size model.
Depth Perception in Visual Simulation.
1980-08-01
effect. Journal of Experimental Psychology, 1953, 45, 205-217. Wallach, H., O’Connell, D. N., & Neisser , U . The memory effect of visual perception of...Wallach and O’Connell labelled this the Kinetic Depth Effect. Wallach, O’Connell, and Neisser (1953) found that once depth had been established...right of fixation in the left eye. The converse is true for objects located 10 uL 0 L-I. M4 ’I! .- 4J Cd > 9 )( C.) U )d 0 0 4- -0 4 C4 J )0 -I,--4 0
Raja, Sheela; Shah, Raveena; Hamad, Judy; Van Kanegan, Mona; Kupershmidt, Alexandra; Kruthoff, Mariela
2015-10-01
Although the importance of empathy, rapport, and anxiety/pain awareness in dentist-patient relations has been well documented, these factors continue to be an issue with patients in many dental school clinics. The aim of this study was to develop an in-depth understanding of how patients at an urban, university-affiliated medical center and its dental school's clinic experienced oral health care and to generate ideas for improving the dental school's clinical curriculum and management of the clinic. Although patient satisfaction surveys are common, in-depth patient narratives are an underutilized resource for improving dental education. In-depth qualitative interviews were conducted with 20 uninsured or underinsured dental patients at these sites, and the results were analyzed using content analysis. Major phenomena that participants discussed were the importance of empathy and good rapport with their oral health providers and provider awareness of dental pain and anxiety. Many patients also discussed feeling dehumanized during dental visits. Based on their positive and negative experiences, the participants made suggestions for how oral health professionals can successfully engage patients in treatment.
The effects of 5.1 sound presentations on the perception of stereoscopic imagery in video games
NASA Astrophysics Data System (ADS)
Cullen, Brian; Galperin, Daniel; Collins, Karen; Hogue, Andrew; Kapralos, Bill
2013-03-01
Stereoscopic 3D (S3D) content in games, film and other audio-visual media has been steadily increasing over the past number of years. However, there are still open, fundamental questions regarding its implementation, particularly as it relates to a multi-modal experience that involves sound and haptics. Research has shown that sound has considerable impact on our perception of 2D phenomena, but very little research has considered how sound may influence stereoscopic 3D. Here we present the results of an experiment that examined the effects of 5.1 surround sound (5.1) and stereo loudspeaker setups on depth perception in relation to S3D imagery within a video game environment. Our aim was to answer the question: "can 5.1 surround sound enhance the participant's perception of depth in the stereoscopic field when compared to traditional stereo sound presentations?" In addition, our study examined how the presence or absence of Doppler frequency shift and frequency fall-off audio effects can also influence depth judgment under these conditions. Results suggest that 5.1 surround sound presentations enhance the apparent depth of stereoscopic imagery when compared to stereo presentations. Results also suggest that the addition of audio effects such as Doppler shift and frequency fall-off filters can influence the apparent depth of S3D objects.
Khan, Tahir Mehmood; Leong, Jamie Pik Yan; Ming, Long Chiau; Khan, Amer Hayat
2015-01-01
Breast cancer is the most common cancer and the leading cause of cancer mortality among women of all ethnic and age groups in Malaysia. Delay in seeking help for breast cancer symptoms is preventable and by identifying possible factors for delayed diagnosis, patient prognosis and survival rates could be improved. This narrative review aimed to understand and evaluate the level of in-depth breast cancer knowledge in terms of clinical breast examination and breast self-examination, and other important aspects such as side-effects and risk factors in Malaysian females. Since Malaysia is multicultural, this review assessed social perceptions, cultural beliefs and help-seeking behaviour in respect to breast cancer among different ethnic groups, since these may impinge on efforts to 'avoid' the disease. A comprehensive literature search of seven databases was performed from December 2015 to January 2015. Screening of relevant published journals was also undertaken to identify available information related to the knowledge, perception and help-seeking behaviour of Malaysian women in relation to breast cancer. A total of 42 articles were appraised and included in this review. Generally, women in Malaysia had good awareness of breast cancer and its screening tools, particularly breast self-examination, but only superficial in-depth knowledge about the disease. Women in rural areas had lower levels of knowledge than those in urban areas. It was also shown that books, magazines, brochures and television were among the most common sources of breast cancer information. Delay in presentation was attributed mainly to a negative social perception of the disease, poverty, cultural and religion practices, and a strong influence of complementary and alternative medicine, rather than a lack of knowledge. This review highlighted the need for an intensive and in-depth breast cancer education campaigns using media and community health programmes, even with the existing good awareness of breast cancer. This is essential in order to avoid misconceptions and to frame the correct mind-set about breast cancer among women in Malaysia. Socio-cultural differences and religious practices should be taken into account by health care professionals when advising on breast cancer. Women need to be aware of the risk factors and symptoms of breast cancer so that early diagnosis can take place and the chances of survival improved.
Depth perception based 3D holograms enabled with polarization-independent metasurfaces.
Deng, Juan; Li, Zile; Zheng, Guoxing; Tao, Jin; Dai, Qi; Deng, Liangui; He, Ping'an; Deng, Qiling; Mao, Qingzhou
2018-04-30
Metasurfaces consist of dielectric nanobrick arrays with different dimensions in the long and short axes can be used to generate different phase delays, predicting a new way to manipulate an incident beam in the two orthogonal directions separately. Here we demonstrate the concept of depth perception based three-dimensional (3D) holograms with polarization-independent metasurfaces. 4-step dielectric metasurfaces-based fan-out optical elements and holograms operating at 658 nm were designed and simulated. Two different holographic images with high fidelity were generated at the same plane in the far field for different polarization states. One can observe the 3D effect of target objects with polarized glasses. With the advantages of ultracompactness, flexibility and replicability, the polarization-independent metasurfaces open up depth perception based stereoscopic imaging in a holographic way.
Modeling of Depth Cue Integration in Manual Control Tasks
NASA Technical Reports Server (NTRS)
Sweet, Barbara T.; Kaiser, Mary K.; Davis, Wendy
2003-01-01
Psychophysical research has demonstrated that human observers utilize a variety of visual cues to form a perception of three-dimensional depth. However, most of these studies have utilized a passive judgement paradigm, and failed to consider depth-cue integration as a dynamic and task-specific process. In the current study, we developed and experimentally validated a model of manual control of depth that examines how two potential cues (stereo disparity and relative size) are utilized in both first- and second-order active depth control tasks. We found that stereo disparity plays the dominate role for determining depth position, while relative size dominates perception of depth velocity. Stereo disparity also plays a reduced role when made less salient (i.e., when viewing distance is increased). Manual control models predict that position information is sufficient for first-order control tasks, while velocity information is required to perform a second-order control task. Thus, the rules for depth-cue integration in active control tasks are dependent on both task demands and cue quality.
Machine learning-based augmented reality for improved surgical scene understanding.
Pauly, Olivier; Diotte, Benoit; Fallavollita, Pascal; Weidert, Simon; Euler, Ekkehard; Navab, Nassir
2015-04-01
In orthopedic and trauma surgery, AR technology can support surgeons in the challenging task of understanding the spatial relationships between the anatomy, the implants and their tools. In this context, we propose a novel augmented visualization of the surgical scene that mixes intelligently the different sources of information provided by a mobile C-arm combined with a Kinect RGB-Depth sensor. Therefore, we introduce a learning-based paradigm that aims at (1) identifying the relevant objects or anatomy in both Kinect and X-ray data, and (2) creating an object-specific pixel-wise alpha map that permits relevance-based fusion of the video and the X-ray images within one single view. In 12 simulated surgeries, we show very promising results aiming at providing for surgeons a better surgical scene understanding as well as an improved depth perception. Copyright © 2014 Elsevier Ltd. All rights reserved.
Clinical Assessment of Stereoacuity and 3-D Stereoscopic Entertainment
Tidbury, Laurence P.; Black, Robert H.; O’Connor, Anna R.
2015-01-01
Abstract Background/Aims: The perception of compelling depth is often reported in individuals where no clinically measurable stereoacuity is apparent. We aim to investigate the potential cause of this finding by varying the amount of stereopsis available to the subject, and assessing their perception of depth viewing 3-D video clips and a Nintendo 3DS. Methods: Monocular blur was used to vary interocular VA difference, consequently creating 4 levels of measurable binocular deficit from normal stereoacuity to suppression. Stereoacuity was assessed at each level using the TNO, Preschool Randot®, Frisby, the FD2, and Distance Randot®. Subjects also completed an object depth identification task using the Nintendo 3DS, a static 3DTV stereoacuity test, and a 3-D perception rating task of 6 video clips. Results: As intraocular VA differences increased, stereoacuity of the 57 subjects (aged 16–62 years) decreased (eg, 110”, 280”, 340”, and suppression). The ability to correctly identify depth on the Nintendo 3DS remained at 100% until suppression of one eye occurred. The perception of a compelling 3-D effect when viewing the video clips was rated high until suppression of one eye occurred, where the 3-D effect was still reported as fairly evident. Conclusion: If an individual has any level of measurable stereoacuity, the perception of 3-D when viewing stereoscopic entertainment is present. The presence of motion in stereoscopic video appears to provide cues to depth, where static cues are not sufficient. This suggests there is a need for a dynamic test of stereoacuity to be developed, to allow fully informed patient management decisions to be made. PMID:26669421
VISIDEP™: visual image depth enhancement by parallax induction
NASA Astrophysics Data System (ADS)
Jones, Edwin R.; McLaurin, A. P.; Cathey, LeConte
1984-05-01
The usual descriptions of depth perception have traditionally required the simultaneous presentation of disparate views presented to separate eyes with the concomitant demand that the resulting binocular parallax be horizontally aligned. Our work suggests that the visual input information is compared in a short-term memory buffer which permits the brain to compute depth as it is normally perceived. However, the mechanism utilized is also capable of receiving and processing the stereographic information even when it is received monocularly or when identical inputs are simultaneously fed to both eyes. We have also found that the restriction to horizontally displaced images is not a necessary requirement and that improvement in image acceptability is achieved by the use of vertical parallax. Use of these ideas permit the presentation of three-dimensional scenes on flat screens in full color without the encumbrance of glasses or other viewing aids.
The visual perception of size and distance.
DOT National Transportation Integrated Search
1962-07-01
The perception of absolute distance has been assumed to be important in the perception of the size of objects and the depth between them. A different hypothesis is proposed. It is asserted that perceived relative size and distance are the primary psy...
Turkish Primary Students' Perceptions of Geography
ERIC Educational Resources Information Center
Senyurt, Secil
2014-01-01
This study provides an in-depth investigation of Turkish primary school students' perceptions of geography. Gender differences in students' perceptions of geography were investigated, including definitions of geography and its field of study. The findings showed that "landforms," "our geographical regions/Turkey,"…
Staying the Distance: Students' Perceptions of Enablers of Transition to Higher Education
ERIC Educational Resources Information Center
Bowles, Angela; Fisher, Ron; McPhail, Ruth; Rosenstreich, Daniela; Dobson, Alexandra
2014-01-01
Students' perceptions during their first semester at university may be critical in the decision to continue or discontinue studies. In this study we consider students' perceptions of what factors enable successful transition to university. Using qualitative research, students' perceptions are obtained by in-depth interviews and focus groups that…
Operational Based Vision Assessment Research: Depth Perception
2014-11-01
13-072 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) USAF School of Aerospace Medicine...Aeromedical Research Department 2510 Fifth St. Wright-Patterson AFB, OH 45433-7913 8. PERFORMING ORGANIZATION REPORT NUMBER AFRL-SA-WP-JA-2014...tests are tests of stereopsis, such as the AFVT and AO Vectograph. Others evaluate depth perception with stereo as a contributor to performance , such
NASA Astrophysics Data System (ADS)
Tyczka, Dale R.; Wright, Robert; Janiszewski, Brian; Chatten, Martha Jane; Bowen, Thomas A.; Skibba, Brian
2012-06-01
Nearly all explosive ordnance disposal robots in use today employ monoscopic standard-definition video cameras to relay live imagery from the robot to the operator. With this approach, operators must rely on shadows and other monoscopic depth cues in order to judge distances and object depths. Alternatively, they can contact an object with the robot's manipulator to determine its position, but that approach carries with it the risk of detonation from unintentionally disturbing the target or nearby objects. We recently completed a study in which high-definition (HD) and stereoscopic video cameras were used in addition to conventional standard-definition (SD) cameras in order to determine if higher resolutions and/or stereoscopic depth cues improve operators' overall performance of various unmanned ground vehicle (UGV) tasks. We also studied the effect that the different vision modes had on operator comfort. A total of six different head-aimed vision modes were used including normal-separation HD stereo, SD stereo, "micro" (reduced separation) SD stereo, HD mono, and SD mono (two types). In general, the study results support the expectation that higher resolution and stereoscopic vision aid UGV teleoperation, but the degree of improvement was found to depend on the specific task being performed; certain tasks derived notably more benefit from improved depth perception than others. This effort was sponsored by the Joint Ground Robotics Enterprise under Robotics Technology Consortium Agreement #69-200902 T01. Technical management was provided by the U.S. Air Force Research Laboratory's Robotics Research and Development Group at Tyndall AFB, Florida.
Use of cues in virtual reality depends on visual feedback.
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.
Corrow, Sherryse L; Mathison, Jordan; Granrud, Carl E; Yonas, Albert
2014-01-01
Corrow, Granrud, Mathison, and Yonas (2011, Perception, 40, 1376-1383) found evidence that 6-month-old infants perceive the hollow face illusion. In the present study we asked whether 6-month-old infants perceive illusory depth reversal for a nonface object and whether infants' perception of the hollow face illusion is affected by mask orientation inversion. In experiment 1 infants viewed a concave bowl, and their reaches were recorded under monocular and binocular viewing conditions. Infants reached to the bowl as if it were convex significantly more often in the monocular than in the binocular viewing condition. These results suggest that infants perceive illusory depth reversal with a nonface stimulus and that the infant visual system has a bias to perceive objects as convex. Infants in experiment 2 viewed a concave face-like mask in upright and inverted orientations. Infants reached to the display as if it were convex more in the monocular than in the binocular condition; however, mask orientation had no effect on reaching. Previous findings that adults' perception of the hollow face illusion is affected by mask orientation inversion have been interpreted as evidence of stored-knowledge influences on perception. However, we found no evidence of such influences in infants, suggesting that their perception of this illusion may not be affected by stored knowledge, and that perceived depth reversal is not face-specific in infants.
Visual Depth from Motion Parallax and Eye Pursuit
Stroyan, Keith; Nawrot, Mark
2012-01-01
A translating observer viewing a rigid environment experiences “motion parallax,” the relative movement upon the observer’s retina of variously positioned objects in the scene. This retinal movement of images provides a cue to the relative depth of objects in the environment, however retinal motion alone cannot mathematically determine relative depth of the objects. Visual perception of depth from lateral observer translation uses both retinal image motion and eye movement. In (Nawrot & Stroyan, 2009, Vision Res. 49, p.1969) we showed mathematically that the ratio of the rate of retinal motion over the rate of smooth eye pursuit mathematically determines depth relative to the fixation point in central vision. We also reported on psychophysical experiments indicating that this ratio is the important quantity for perception. Here we analyze the motion/pursuit cue for the more general, and more complicated, case when objects are distributed across the horizontal viewing plane beyond central vision. We show how the mathematical motion/pursuit cue varies with different points across the plane and with time as an observer translates. If the time varying retinal motion and smooth eye pursuit are the only signals used for this visual process, it is important to know what is mathematically possible to derive about depth and structure. Our analysis shows that the motion/pursuit ratio determines an excellent description of depth and structure in these broader stimulus conditions, provides a detailed quantitative hypothesis of these visual processes for the perception of depth and structure from motion parallax, and provides a computational foundation to analyze the dynamic geometry of future experiments. PMID:21695531
Asghar, Khudejha; Mayevskaya, Yana; Sommer, Marni; Razzaque, Ayesha; Laird, Betsy; Khan, Yasmin; Qureshi, Shamsa; Falb, Kathryn; Stark, Lindsay
2018-04-10
Promoting resilience among displaced adolescent girls in northern Pakistan may buffer against developmental risks such as violence exposure and associated longer-term consequences for physical and mental well-being. However, girls' access to such programming may be limited by social norms restricting movement. A mixed-method evaluation examined change over time, feasibility, and acceptability of the COMPASS program in three districts of Khyber-Pakhtunkhwa province through a single-group within-participant pretest-posttest of adolescent girls aged 12-19 enrolled in the intervention (n = 78), and qualitative in-depth interviews with girls following posttest completion (n = 15). Primary outcomes included improvements in movement, safety, and comfort discussing life skills topics with caregivers, operationalized quantitatively as number of places visited in the previous month, number of spaces that girls felt safe visiting, and comfort discussing puberty, education, working outside the home, and marriage, respectively. Secondary outcomes included psychosocial well-being, gendered rites of passage, social support networks, perceptions of support for survivors of violence, and knowledge of services. Quantitative pretest-posttest findings included significant improvements in movement, psychosocial well-being, and some improvements in social support, knowledge of services, and gendered rites of passage; findings on safety and comfort discussing life skills topics were not significant. Qualitative findings illuminated themes related to definitions of safety and freedom of movement, perceptions and acceptability of program content, perceptions of social support, and perceptions of blame and support and knowledge of services in response to violence. Taken together, findings illustrate positive impacts of life skills programming, and the need for societal changes on gender norms to improve girls' safety in public spaces and access to resources.
Audio–visual interactions for motion perception in depth modulate activity in visual area V3A
Ogawa, Akitoshi; Macaluso, Emiliano
2013-01-01
Multisensory signals can enhance the spatial perception of objects and events in the environment. Changes of visual size and auditory intensity provide us with the main cues about motion direction in depth. However, frequency changes in audition and binocular disparity in vision also contribute to the perception of motion in depth. Here, we presented subjects with several combinations of auditory and visual depth-cues to investigate multisensory interactions during processing of motion in depth. The task was to discriminate the direction of auditory motion in depth according to increasing or decreasing intensity. Rising or falling auditory frequency provided an additional within-audition cue that matched or did not match the intensity change (i.e. intensity-frequency (IF) “matched vs. unmatched” conditions). In two-thirds of the trials, a task-irrelevant visual stimulus moved either in the same or opposite direction of the auditory target, leading to audio–visual “congruent vs. incongruent” between-modalities depth-cues. Furthermore, these conditions were presented either with or without binocular disparity. Behavioral data showed that the best performance was observed in the audio–visual congruent condition with IF matched. Brain imaging results revealed maximal response in visual area V3A when all cues provided congruent and reliable depth information (i.e. audio–visual congruent, IF-matched condition including disparity cues). Analyses of effective connectivity revealed increased coupling from auditory cortex to V3A specifically in audio–visual congruent trials. We conclude that within- and between-modalities cues jointly contribute to the processing of motion direction in depth, and that they do so via dynamic changes of connectivity between visual and auditory cortices. PMID:23333414
NASA Astrophysics Data System (ADS)
Kim, Hak-Rin; Park, Min-Kyu; Choi, Jun-Chan; Park, Ji-Sub; Min, Sung-Wook
2016-09-01
Three-dimensional (3D) display technology has been studied actively because it can offer more realistic images compared to the conventional 2D display. Various psychological factors such as accommodation, binocular parallax, convergence and motion parallax are used to recognize a 3D image. For glass-type 3D displays, they use only the binocular disparity in 3D depth cues. However, this method cause visual fatigue and headaches due to accommodation conflict and distorted depth perception. Thus, the hologram and volumetric display are expected to be an ideal 3D display. Holographic displays can represent realistic images satisfying the entire factors of depth perception. But, it require tremendous amount of data and fast signal processing. The volumetric 3D displays can represent images using voxel which is a physical volume. However, it is required for large data to represent the depth information on voxel. In order to simply encode 3D information, the compact type of depth fused 3D (DFD) display, which can create polarization distributed depth map (PDDM) image having both 2D color image and depth image is introduced. In this paper, a new volumetric 3D display system is shown by using PDDM image controlled by polarization controller. In order to introduce PDDM image, polarization states of the light through spatial light modulator (SLM) was analyzed by Stokes parameter depending on the gray level. Based on the analysis, polarization controller is properly designed to convert PDDM image into sectioned depth images. After synchronizing PDDM images with active screens, we can realize reconstructed 3D image. Acknowledgment This work was supported by `The Cross-Ministry Giga KOREA Project' grant from the Ministry of Science, ICT and Future Planning, Korea
Teachers' Perception of Social Justice in Mathematics Classrooms
ERIC Educational Resources Information Center
Panthi, Ram Krishna; Luitel, Bal Chandra; Belbase, Shashidhar
2017-01-01
The purpose of this study was to explore mathematics teachers' perception of social justice in mathematics classrooms. We applied interpretive qualitative method for data collection, analysis, and interpretation through iterative process. We administered in-depth semi-structured interviews to capture the perceptions of three mathematics teachers…
Teachers' Perception of Social Justice in Mathematics Classrooms
ERIC Educational Resources Information Center
Panthi, Ram Krishna; Luitel, Bal Chandra; Belbase, Shashidhar
2018-01-01
The purpose of this study was to explore mathematics teachers' perception of social justice in mathematics classrooms. We applied interpretive qualitative method for data collection, analysis, and interpretation through iterative process. We administered in-depth semi-structured interviews to capture the perceptions of three mathematics teachers…
Friedman, Daniela B; Tanner, Andrea; Rose, India D
2014-04-01
Journalists have a unique opportunity to educate the community about public health and health care. In order for health communication messages to be effective, characteristics of the intended audience must be considered. Limited attention has been given to health journalists' perceptions of their target communities and little is known about how journalists' perceptions may impact the delivery of health information in the news. Fifteen in-depth telephone interviews were conducted with health journalists from varying geographic regions and media market sizes. Interview questions examined health journalists' perceptions of their target communities, the content and delivery of their health-related stories, and the current state of health journalism. Interviews were audio-recorded for transcription and thematic analysis. Health journalists perceived their audiences to be primarily mothers and adults with limited education. Participants reported they often used personal stories and strong headlines to engage their communities. They also stated that their news stories were quite technical and may not have been written at an appropriate reading level for their audience. When asked about the current state of health journalism, participants reported that there were areas for improvement. Journalists stated that increased collaborations with public health practitioners would improve their own understanding of health and medical information and allow them to develop health news content that was more appropriate for their target communities.
Intubation simulation with a cross-sectional visual guidance.
Rhee, Chi-Hyoung; Kang, Chul Won; Lee, Chang Ha
2013-01-01
We present an intubation simulation with deformable objects and a cross-sectional visual guidance using a general haptic device. Our method deforms the tube model when it collides with the human model. Mass-Spring model with the Euler integration is used for the tube deformation. For the trainee's more effective understanding of the intubation process, we provide a cross-sectional view of the oral cavity and the tube. Our system also applies a stereoscopic rendering to improve the depth perception and the reality of the simulation.
Preoperative warm-up the key to improved resident technique: a randomized study.
Moran-Atkin, Erin; Abdalla, Gamal; Chen, Grace; Magnuson, Thomas H; Lidor, Anne O; Schweitzer, Michael A; Steele, Kimberley E
2015-05-01
The ACGME has required that a skills lab be incorporated into the surgical residency curriculum. While the value of warm-up is generally accepted in other areas requiring complex motor skills, there is little evidence to support the benefits of warm-up prior to performing surgery. We are conducting this study in an attempt to identify whether a warm-up period prior to operating impacts operative technique. All general surgery residents and MIS fellows were included in this IRB-approved randomized study. Participants were randomized to either warm-up or no warm-up groups. Participants randomized to the warm-up group completed a 10 min practice session in the simulation lab within 1 h of starting the case, using an FLS training box. At the conclusion of the operation, the participant was evaluated by the attending surgeon using the validated global rating scales of Reznick and Vassiliou. The attending surgeons were blinded to the use of pre-procedure warm-up. The results of the questionnaire were analyzed using student's t test with p < 0.05 for significance. Pilot data were obtained after completing 40 cases that were randomized to warm-up (19) or no warm-up (21). There was a statistically significant improvement in depth perception (p = 0.02), bimanual dexterity (p = 0.01), and efficiency of movements (p = 0.03) for those randomized to warm-up. There was statistical improvement when we preformed a composite scoring of the attending evaluations for each of the Reznick (p = 0.008) and the Vassiliou (p = 0.01) global rating scales. Preoperative warm-up significantly improves depth perception, bimanual dexterity, and efficiency of movements, as well as improvement in composite scores as judged by the attending surgeon. The lack of self-perceived improvement by the residents may be a reflection of the high standards and intense self-critique that is common among surgical trainees. We believe that our findings, while preliminary, reflect that surgical performance can be enhanced through structured warm-up activities.
Prolonged maturation of auditory perception and learning in gerbils
Sarro, Emma C.; Sanes, Dan H.
2011-01-01
In humans, auditory perception reaches maturity over a broad age range, extending through adolescence. Despite this slow maturation, children are considered to be outstanding learners, suggesting that immature perceptual skills might actually be advantageous to improvement on an acoustic task as a result of training (perceptual learning). Previous non-human studies have not employed an identical task when comparing perceptual performance of young and mature subjects, making it difficult to assess learning. Here, we used an identical procedure on juvenile and adult gerbils to examine the perception of amplitude modulation (AM), a stimulus feature that is an important component of most natural sounds. On average, Adult animals could detect smaller fluctuations in amplitude (i.e. smaller modulation depths) than Juveniles, indicating immature perceptual skills in Juveniles. However, the population variance was much greater for Juveniles, a few animals displaying adult-like AM detection. To determine whether immature perceptual skills facilitated learning, we compared naïve performance on the AM detection task with the amount of improvement following additional training. The amount of improvement in Adults correlated with naïve performance: those with the poorest naïve performance improved the most. In contrast, the naïve performance of Juveniles did not predict the amount of learning. Those Juveniles with immature AM detection thresholds did not display greater learning than Adults. Furthermore, for several of the Juveniles with adult-like thresholds, AM detection deteriorated with repeated testing. Thus, immature perceptual skills in young animals were not associated with greater learning. PMID:20506133
NASA Astrophysics Data System (ADS)
Simonovich, Jennifer A.; Towers, Emily; Zastavker, Yevgeniya V.
2012-02-01
Project-based learning (PjBL) has been shown to improve students' performance and satisfaction with their coursework, particularly in science and engineering courses. Specific aspects of PjBL that contribute to this improvement are student autonomy, course scaffolding, and instructor support. This study investigates two PjBL courses required for engineering majors at a small technical school, Introductory Mechanics Laboratory and Introductory Engineering Design. The three data sources used in this work are classroom observations (one laboratory and four design sessions) and semi-structured in-depth interviews with twelve students and six faculty. Grounded theory approach is used in a two-step fashion by (1) analyzing each data set individually and (2) performing full triangulation of all three data sets. In this talk, we demonstrate the relationship between faculty intentions and student perceptions regarding the three PjBL aspects -- student autonomy, course scaffolding, and instructor support -- within the context of these two courses. We further discuss implications for the course design and professional development of faculty.
Neural Integration of Information Specifying Human Structure from Form, Motion, and Depth
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
Gender inequities in health: an exploratory qualitative study of Saudi women's perceptions.
Alyaemni, Asmaa; Theobald, Sally; Faragher, Brian; Jehan, Kate; Tolhurst, Rachel
2013-01-01
This study aimed to explore Saudi Arabian women's perceptions of how gendered social structures affect their health by understanding their perceptions of these influences on their health relative to those on men's health. Qualitative methods, including focus group discussions (FGDs) and in-depth individual interviews (IDIs) were conducted with 66 married women in Riyadh, the capital city. Participants were purposively sampled for maximum variation, including consideration of socio-economic status, age, educational level, health status and the use of healthcare. The majority of women perceived their health to be worse than men's and attributed this to their childbearing, domestic and care-giving roles, restrictions on their mobility, poverty and psychological stress related to their responsibilities for children, and marital conflict. A minority of participants felt that men's health was worse than women's and related this to their gendered roles as "breadwinners," greater mobility and masculine norms and identities. Gender equity should be a health policy priority to improve women's health.
Peer assisted learning as a formal instructional tool.
Naqi, Syed Asghar
2014-03-01
To explore the utility of peer assisted learning (PAL) in medical schools as a formal instructional tool. Grounded theory approach. King Edward Medical University, Lahore, from July 2011 to December 2011. A study was designed using semi-structured in-depth interviews to collect data from final year medical students (n=6), residents (n=4) and faculty members (n=3), selected on the basis of non-probability purposive sampling. The qualitative data thus generated was first translated in English and transcribed and organized into major categories by using a coding framework. Participants were interviewed two more times to further explore their perceptions and experiences related to emergent categories. An iterative process was employed using grounded theory analysis technique to eventually generate theory. PAL was perceived as rewarding in terms of fostering higher order thinking, effective teaching skills and in improving self efficacy among learners. PAL can offer learning opportunity to medical students, residents and faculty members. It can improve depth of their knowledge and skills.
The role of eye movements in depth from motion parallax during infancy
Nawrot, Elizabeth; Nawrot, Mark
2013-01-01
Motion parallax is a motion-based, monocular depth cue that uses an object's relative motion and velocity as a cue to relative depth. In adults, and in monkeys, a smooth pursuit eye movement signal is used to disambiguate the depth-sign provided by these relative motion cues. The current study investigates infants' perception of depth from motion parallax and the development of two oculomotor functions, smooth pursuit and the ocular following response (OFR) eye movements. Infants 8 to 20 weeks of age were presented with three tasks in a single session: depth from motion parallax, smooth pursuit tracking, and OFR to translation. The development of smooth pursuit was significantly related to age, as was sensitivity to motion parallax. OFR eye movements also corresponded to both age and smooth pursuit gain, with groups of infants demonstrating asymmetric function in both types of eye movements. These results suggest that the development of the eye movement system may play a crucial role in the sensitivity to depth from motion parallax in infancy. Moreover, describing the development of these oculomotor functions in relation to depth perception may aid in the understanding of certain visual dysfunctions. PMID:24353309
Optimal combination of illusory and luminance-defined 3-D surfaces: A role for ambiguity.
Hartle, Brittney; Wilcox, Laurie M; Murray, Richard F
2018-04-01
The shape of the illusory surface in stereoscopic Kanizsa figures is determined by the interpolation of depth from the luminance edges of adjacent inducing elements. Despite ambiguity in the position of illusory boundaries, observers reliably perceive a coherent three-dimensional (3-D) surface. However, this ambiguity may contribute additional uncertainty to the depth percept beyond what is expected from measurement noise alone. We evaluated the intrinsic ambiguity of illusory boundaries by using a cue-combination paradigm to measure the reliability of depth percepts elicited by stereoscopic illusory surfaces. We assessed the accuracy and precision of depth percepts using 3-D Kanizsa figures relative to luminance-defined surfaces. The location of the surface peak was defined by illusory boundaries, luminance-defined edges, or both. Accuracy and precision were assessed using a depth-discrimination paradigm. A maximum likelihood linear cue combination model was used to evaluate the relative contribution of illusory and luminance-defined signals to the perceived depth of the combined surface. Our analysis showed that the standard deviation of depth estimates was consistent with an optimal cue combination model, but the points of subjective equality indicated that observers consistently underweighted the contribution of illusory boundaries. This systematic underweighting may reflect a combination rule that attributes additional intrinsic ambiguity to the location of the illusory boundary. Although previous studies show that illusory and luminance-defined contours share many perceptual similarities, our model suggests that ambiguity plays a larger role in the perceptual representation of illusory contours than of luminance-defined contours.
Wilkins, Luke; Gray, Rob; Gaska, James; Winterbottom, Marc
2013-12-30
A driving simulator was used to examine the relationship between motion perception and driving performance. Although motion perception test scores have been shown to be related to driving safety, it is not clear which combination of tests are the best predictors and whether motion perception training can improve driving performance. In experiment 1, 60 younger drivers (22.4 ± 2.5 years) completed three motion perception tests (2-dimensional [2D] motion-defined letter [MDL] identification, 3D motion in depth sensitivity [MID], and dynamic visual acuity [DVA]) followed by two driving tests (emergency braking [EB] and hazard perception [HP]). In experiment 2, 20 drivers (21.6 ± 2.1 years) completed 6 weeks of motion perception training (using the MDL, MID, and DVA tests), while 20 control drivers (22.0 ± 2.7 years) completed an online driving safety course. The EB performance was measured before and after training. In experiment 1, MDL (r = 0.34) and MID (r = 0.46) significantly correlated with EB score. The change in DVA score as a function of target speed (i.e., "velocity susceptibility") was correlated most strongly with HP score (r = -0.61). In experiment 2, the motion perception training group had a significant decrease in brake reaction time on the EB test from pre- to posttreatment, while there was no significant change for the control group: t(38) = 2.24, P = 0.03. Tests of 3D motion perception are the best predictor of EB, while DVA velocity susceptibility is the best predictor of hazard perception. Motion perception training appears to result in faster braking responses.
Evaluating motion parallax and stereopsis as depth cues for autostereoscopic displays
NASA Astrophysics Data System (ADS)
Braun, Marius; Leiner, Ulrich; Ruschin, Detlef
2011-03-01
The perception of space in the real world is based on multifaceted depth cues, most of them monocular, some binocular. Developing 3D-displays raises the question, which of these depth cues are predominant and should be simulated by computational means in such a panel. Beyond the cues based on image content, such as shadows or patterns, Stereopsis and depth from motion parallax are the most significant mechanisms supporting observers with depth information. We set up a carefully designed test situation, widely excluding undesired other distance hints. Thereafter we conducted a user test to find out, which of these two depth cues is more relevant and whether a combination of both would increase accuracy in a depth estimation task. The trials were conducting utilizing our autostereoscopic "Free2C"-displays, which are capable to detect the user eye position and steer the image lobes dynamically into that direction. At the same time, eye position was used to update the virtual camera's location and thereby offering motion parallax to the observer. As far as we know, this was the first time that such a test has been conducted using an autosteresocopic display without any assistive technologies. Our results showed, in accordance with prior experiments, that both cues are effective, however Stereopsis is by order of magnitude more relevant. Combining both cues improved the precision of distance estimation by another 30-40%.
Sampling artifacts in perspective and stereo displays
NASA Astrophysics Data System (ADS)
Pfautz, Jonathan D.
2001-06-01
The addition of stereo cues to perspective displays is generally expected to improve the perception of depth. However, the display's pixel array samples both perspective and stereo depth cues, introducing inaccuracies and inconsistencies into the representation of an object's depth. The position, size and disparity of an object will be inaccurately presented and size and disparity will be inconsistently presented across depth. These inconsistencies can cause the left and right edges of an object to appear at different stereo depths. This paper describes how these inconsistencies result in conflicts between stereo and perspective depth information. A relative depth judgement task was used to explore these conflicts. Subjects viewed two objects and reported which appeared closer. Three conflicts resulting from inconsistencies caused by sampling were examined: (1) Perspective size and location versus stereo disparity. (2) Perspective size versus perspective location and stereo disparity. (3) Left and right edge disparity versus perspective size and location. In the first two cases, subjects achieved near-perfect accuracy when perspective and disparity cues were complementary. When size and disparity were inconsistent and thus in conflict, stereo dominated perspective. Inconsistency between the disparities of the horizontal edges of an object confused the subjects, even when complementary perspective and stereo information was provided. Since stereo was the dominant cue and was ambiguous across the object, this led to significantly reduced accuracy. Edge inconsistencies also led to more complaints about visual fatigue and discomfort.
Modeling depth from motion parallax with the motion/pursuit ratio
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
Segregation of Form, Color, Movement, and Depth: Anatomy, Physiology, and Perception
NASA Astrophysics Data System (ADS)
Livingstone, Margaret; Hubel, David
1988-05-01
Anatomical and physiological observations in monkeys indicate that the primate visual system consists of several separate and independent subdivisions that analyze different aspects of the same retinal image: cells in cortical visual areas 1 and 2 and higher visual areas are segregated into three interdigitating subdivisions that differ in their selectivity for color, stereopsis, movement, and orientation. The pathways selective for form and color seem to be derived mainly from the parvocellular geniculate subdivisions, the depth- and movement-selective components from the magnocellular. At lower levels, in the retina and in the geniculate, cells in these two subdivisions differ in their color selectivity, contrast sensitivity, temporal properties, and spatial resolution. These major differences in the properties of cells at lower levels in each of the subdivisions led to the prediction that different visual functions, such as color, depth, movement, and form perception, should exhibit corresponding differences. Human perceptual experiments are remarkably consistent with these predictions. Moreover, perceptual experiments can be designed to ask which subdivisions of the system are responsible for particular visual abilities, such as figure/ground discrimination or perception of depth from perspective or relative movement--functions that might be difficult to deduce from single-cell response properties.
Usability of stereoscopic view in teleoperation
NASA Astrophysics Data System (ADS)
Boonsuk, Wutthigrai
2015-03-01
Recently, there are tremendous growths in the area of 3D stereoscopic visualization. The 3D stereoscopic visualization technology has been used in a growing number of consumer products such as the 3D televisions and the 3D glasses for gaming systems. This technology refers to the idea that human brain develops depth of perception by retrieving information from the two eyes. Our brain combines the left and right images on the retinas and extracts depth information. Therefore, viewing two video images taken at slightly distance apart as shown in Figure 1 can create illusion of depth [8]. Proponents of this technology argue that the stereo view of 3D visualization increases user immersion and performance as more information is gained through the 3D vision as compare to the 2D view. However, it is still uncertain if additional information gained from the 3D stereoscopic visualization can actually improve user performance in real world situations such as in the case of teleoperation.
The visual perception of spatial extent.
DOT National Transportation Integrated Search
1963-09-01
This study was concerned with the manner in which perceived depth and perceived frontoparallel size varied with physical distance and hence with each other. An equation expressing the relation between perceived frontoparallel size and physical depth ...
Hadi, Khatereh; DuBose, Jennifer R; Ryherd, Erica
2016-04-01
This study investigates the perception of nurses about their lighting environment at medical-surgical hospital units in order to understand areas of improvement for lighting at these units. The bulk of the research about nurses and lighting is focused on nighttime nursing, exploring the disruptions of nurses' circadian rhythm and maintaining alertness. The understanding of nurses' perception about lighting and its impact on nurses' task performance and patient examination remains imprecise. This study used an online survey to ask a set of questions about lighting in medical-surgical units at five key locations including centralized nurse stations, decentralized nurse stations (DCNS), patient bedsides, patient bathrooms, and corridors from 393 survey participants. It then explored the survey findings in more depth through conducting focus groups with eight volunteer nurses. Lighting conditions at patient besides and DCNSs were significantly less desirable for nurses compared to other locations. A significant relationship between nurses' access to lighting controls (switches and dimmers) and satisfaction about the lighting environment was found. No significant relationship was observed between the individual characteristics of nurses (such as age, years of experience, etc.) and findings of this study. Thoughtful design of the lighting environment can improve nurses' satisfaction and perception about their working environment. © The Author(s) 2015.
Williams, Brian; Mukhopadhyay, Somnath; Dowell, Jon; Coyle, Joanne
2007-07-30
Although chest physiotherapy is central to the management of cystic fibrosis (CF), adherence among children is problematic. This study explores accounts by parents and children of the difficulties of adhering to chest physiotherapy for cystic fibrosis, and identifies strategies used by families to overcome these. A qualitative study based on in-depth interviews with 32 children with a diagnosis of cystic fibrosis aged 7 - 17 years, and with 31 parents. Physiotherapy was frequently described as restrictive, threatening to identity and boring, giving rise to feelings of unfairness, inequality, 'difference', and social stigma. Motivation to adhere was influenced by perceptions of effectiveness that depended on external signs evident during or after the physiotherapy. Motivation was enhanced where parents and children visualized the accumulation of mucus. Some parents had developed distraction techniques that improved the experience of chest physiotherapy but had few opportunities to share these with other parents. The experience of physiotherapy is problematic to some parents and children. Furthermore, motivation to overcome these problems may be undermined by perceptions of ineffectiveness. Distraction techniques that change the value that the child places on the time spent doing physiotherapy and that reduces their perception of its duration may improve experience and adherence. The potential of visualization techniques to promote adherence should be investigated further.
Chromatic assimilation unaffected by perceived depth of inducing light.
Shevell, Steven K; Cao, Dingcai
2004-01-01
Chromatic assimilation is a shift toward the color of nearby light. Several studies conclude that a neural process contributes to assimilation but the neural locus remains in question. Some studies posit a peripheral process, such as retinal receptive-field organization, while others claim the neural mechanism follows depth perception, figure/ground segregation, or perceptual grouping. The experiments here tested whether assimilation depends on a neural process that follows stereoscopic depth perception. By introducing binocular disparity, the test field judged in color was made to appear in a different depth plane than the light that induced assimilation. The chromaticity and spatial frequency of the inducing light, and the chromaticity of the test light, were varied. Chromatic assimilation was found with all inducing-light sizes and chromaticities, but the magnitude of assimilation did not depend on the perceived relative depth planes of the test and inducing fields. We found no evidence to support the view that chromatic assimilation depends on a neural process that follows binocular combination of the two eyes' signals.
Leopold, David A.; Humphreys, Glyn W.; Welchman, Andrew E.
2016-01-01
The posterior parietal cortex (PPC) is understood to be active when observers perceive three-dimensional (3D) structure. However, it is not clear how central this activity is in the construction of 3D spatial representations. Here, we examine whether PPC is essential for two aspects of visual depth perception by testing patients with lesions affecting this region. First, we measured subjects' ability to discriminate depth structure in various 3D surfaces and objects using binocular disparity. Patients with lesions to right PPC (N = 3) exhibited marked perceptual deficits on these tasks, whereas those with left hemisphere lesions (N = 2) were able to reliably discriminate depth as accurately as control subjects. Second, we presented an ambiguous 3D stimulus defined by structure from motion to determine whether PPC lesions influence the rate of bistable perceptual alternations. Patients' percept durations for the 3D stimulus were generally within a normal range, although the two patients with bilateral PPC lesions showed the fastest perceptual alternation rates in our sample. Intermittent stimulus presentation reduced the reversal rate similarly across subjects. Together, the results suggest that PPC plays a causal role in both inferring and maintaining the perception of 3D structure with stereopsis supported primarily by the right hemisphere, but do not lend support to the view that PPC is a critical contributor to bistable perceptual alternations. This article is part of the themed issue ‘Vision in our three-dimensional world’. PMID:27269606
ERIC Educational Resources Information Center
Slaughter, Sandra Lorraine Hawks
2013-01-01
This qualitative descriptive case study, "Knowledge Worker Perceptions of Telework in the New York Metropolitan Area," was conducted to explore the perceptions of knowledge workers who commute to a physical workplace in the New York Metropolitan area (NYMA). In-depth interviews were conducted with fourteen NYMA commuters who are…
ERIC Educational Resources Information Center
Zacharis, Georgios S.; Mikropoulos, Tassos A.; Priovolou, Chryssi
2013-01-01
Previous studies report the involvement of specific brain activation in stereoscopic vision and the perception of depth information. This work presents the first comparative results of adult women on the effects of stereoscopic perception in three different static environments; a real, a two dimensional (2D) and a stereoscopic three dimensional…
Shumba, Constance Sibongile; Kielmann, Karina; Witter, Sophie
2017-12-06
An in-depth understanding of how organizational culture is experienced by health workers (HWs), and influences their decisions to leave their jobs is a fundamental, yet under-examined, basis for forming effective retention strategies. This research examined HWs' working experiences and perceptions of organisational culture within private-not-for-profit, largely mission-based hospitals, and how this influenced retention. Thirty-two HWs, including managers, in 19 health facilities in Uganda were interviewed using a semi-structured topic guide. Interview transcripts were analysed using thematic content analysis. Interviews showed that the organizational culture was predominantly hierarchical, with non-participative management styles which emphasized control and efficiency. HWs and managers held different perceptions of the organizational culture. While the managers valued results and performance, HWs valued team work, recognition and participative management. The findings of this study indicate that organizational culture influences retention of HWs in health facilities and provide a useful context to inform health care managers in the PNFP sub-sector in Uganda and similar contexts. To improve retention of HWs, a gradual shift in organizational culture will be necessary, focussing on the values, beliefs and perceptions which have the greatest influence on observable behaviour.
Usfar, Avita A; Iswarawanti, Dwi N; Davelyna, Devy; Dillon, Drupadi
2010-01-01
To examine caregivers' perceptions and practices related to food and personal hygiene and its association with diarrhea in children 6 to 36 months of age who suffered recurrent diarrhea. This qualitative study, conducted in March and April 2006, used both in-depth interviews and direct observation data. Urban Tangerang, near Jakarta, Indonesia. Twenty-four mothers whose monthly household income was less than $160 US and had latrines in their homes. To examine the relationship between mothers' perceptions and behaviors related to diarrhea, food hygiene, and personal hygiene. Interview transcripts were analyzed based on the phenomenon of interest and coded for common themes. Mothers differentiated diarrhea episodes as either disease or nondisease. Most mothers associated the importance of food hygiene with disease prevention, contaminating agents, and health. Mothers commonly wiped cutting boards with a kitchen towel after slicing vegetables, whereas they washed the board with soap and water after cutting raw meat. Mothers perceived that the importance of personal hygiene was for maintaining health and cleanliness. The majority of mothers washed their hands without soap after performing housework and cooking. Improving mothers' knowledge while incorporating existing perceptions might lead to positive changes.
Depth Perception in Space Artist Concept
2007-05-30
This artist concept shows how astronomers use the unique orbit of NASA Spitzer Space Telescope and a depth-perceiving trick called parallax to determine the distance of dark planets, black holes and failed stars that lurk invisibly among us.
Integration time for the perception of depth from motion parallax.
Nawrot, Mark; Stroyan, Keith
2012-04-15
The perception of depth from relative motion is believed to be a slow process that "builds-up" over a period of observation. However, in the case of motion parallax, the potential accuracy of the depth estimate suffers as the observer translates during the viewing period. Our recent quantitative model for the perception of depth from motion parallax proposes that relative object depth (d) can be determined from retinal image motion (dθ/dt), pursuit eye movement (dα/dt), and fixation distance (f) by the formula: d/f≈dθ/dα. Given the model's dynamics, it is important to know the integration time required by the visual system to recover dα and dθ, and then estimate d. Knowing the minimum integration time reveals the incumbent error in this process. A depth-phase discrimination task was used to determine the time necessary to perceive depth-sign from motion parallax. Observers remained stationary and viewed a briefly translating random-dot motion parallax stimulus. Stimulus duration varied between trials. Fixation on the translating stimulus was monitored and enforced with an eye-tracker. The study found that relative depth discrimination can be performed with presentations as brief as 16.6 ms, with only two stimulus frames providing both retinal image motion and the stimulus window motion for pursuit (mean range=16.6-33.2 ms). This was found for conditions in which, prior to stimulus presentation, the eye was engaged in ongoing pursuit or the eye was stationary. A large high-contrast masking stimulus disrupted depth-discrimination for stimulus presentations less than 70-75 ms in both pursuit and stationary conditions. This interval might be linked to ocular-following response eye-movement latencies. We conclude that neural mechanisms serving depth from motion parallax generate a depth estimate much more quickly than previously believed. We propose that additional sluggishness might be due to the visual system's attempt to determine the maximum dθ/dα ratio for a selection of points on a complicated stimulus. Copyright © 2012 Elsevier Ltd. All rights reserved.
Kambala, Christabel; Lohmann, Julia; Mazalale, Jacob; Brenner, Stephan; Sarker, Malabika; Muula, Adamson S; De Allegri, Manuela
2017-06-08
In 2013, Malawi with its development partners introduced a Results-Based Financing for Maternal and Newborn Health (RBF4MNH) intervention to improve the quality of maternal and newborn health-care services. Financial incentives are awarded to health facilities conditional on their performance and to women for delivering in the health facility. We assessed the effect of the RBF4MNH on quality of care from women's perspectives. We used a mixed-method prospective sequential controlled pre- and post-test design. We conducted 3060 structured client exit interviews, 36 in-depth interviews and 29 focus group discussions (FGDs) with women and 24 in-depth interviews with health service providers between 2013 and 2015. We used difference-in-differences regression models to measure the effect of the RBF4MNH on experiences and perceived quality of care. We used qualitative data to explore the matter more in depth. We did not observe a statistically significant effect of the intervention on women's perceptions of technical care, quality of amenities and interpersonal relations. However, in the qualitative interviews, most women reported improved health service provision as a result of the intervention. RBF4MNH increased the proportion of women reporting to have received medications/treatment during childbirth. Participants in interviews expressed that drugs, equipment and supplies were readily available due to the RBF4MNH. However, women also reported instances of neglect, disrespect and verbal abuse during the process of care. Providers attributed these negative instances to an increased workload resulting from an increased number of women seeking services at RBF4MNH facilities. Our qualitative findings suggest improvements in the availability of drugs and supplies due to RBF4MNH. Despite the intervention, challenges in the provision of quality care persisted, especially with regard to interpersonal relations. RBF interventions may need to consider including indicators that specifically target the provision of respectful maternity care as a means to foster providers' positive attitudes towards women in labour. In parallel, governments should consider enhancing staff and infrastructural capacity before implementing RBF.
Aging and the visual perception of exocentric distance.
Norman, J Farley; Adkins, Olivia C; Norman, Hideko F; Cox, Andrea G; Rogers, Connor E
2015-04-01
The ability of 18 younger and older adults to visually perceive exocentric distances was evaluated. The observers judged the extent of fronto-parallel and in-depth spatial intervals at a variety of viewing distances from 50cm to 164.3cm. Most of the observers perceived in-depth intervals to be significantly smaller than fronto-parallel intervals, a finding that is consistent with previous studies. While none of the individual observers' judgments of exocentric distance were accurate, the judgments of the older observers were significantly more accurate than those of the younger observers. The precision of the observers' judgments across repeated trials, however, was not affected by age. The results demonstrate that increases in age can produce significant improvements in the visual ability to perceive the magnitude of exocentric distances. Copyright © 2015 Elsevier Ltd. All rights reserved.
The visual perception of exocentric distance in outdoor settings.
Norman, J Farley; Adkins, Olivia C; Pedersen, Lauren E; Reyes, Cecia M; Wulff, Rachel A; Tungate, Alex
2015-12-01
The ability of 20 younger (mean age was 21.8years) and older adults (mean age was 71.5years) to visually perceive exocentric distances outdoors was evaluated. The observers adjusted the extent of in-depth spatial intervals until they appeared identical to fronto-parallel intervals of 4 and 8m. The frontal and in-depth intervals were viewed from a distance of 8m. Almost all of the observers' judgments were inaccurate and most reflected perceptual compressions in depth: e.g., an in-depth interval of 10m would appear to have the same extent as a physically smaller 8m frontal interval. Some observers' judgments, however, were consistent with perceptual expansions of in-depth intervals. No significant effects of age were obtained in the current study: both younger and older adults exhibited perceptual compressions and expansions of in-depth intervals. This outcome differs from that of a recent experiment conducted by our laboratory (Vision Research 109 (2015) 52-58) that found the judgments of younger adults to be less accurate than those of older adults. A comparison of the former and current results revealed that while older adults perform similarly outdoors and indoors, the accuracy of younger adults' exocentric judgements improves substantially in outdoor settings (so that the accuracy becomes similar to that exhibited by older adults). Copyright © 2015 Elsevier Ltd. All rights reserved.
False Color Terrain Model of Phoenix Workspace
2008-05-28
This is a terrain model of Phoenix Robotic Arm workspace. It has been color coded by depth with a lander model for context. The model has been derived using images from the depth perception feature from Phoenix Surface Stereo Imager SSI.
Landwehr, Markus; Fürstenberg, Dirk; Walger, Martin; von Wedel, Hasso; Meister, Hartmut
2014-01-01
Advances in speech coding strategies and electrode array designs for cochlear implants (CIs) predominantly aim at improving speech perception. Current efforts are also directed at transmitting appropriate cues of the fundamental frequency (F0) to the auditory nerve with respect to speech quality, prosody, and music perception. The aim of this study was to examine the effects of various electrode configurations and coding strategies on speech intonation identification, speaker gender identification, and music quality rating. In six MED-EL CI users electrodes were selectively deactivated in order to simulate different insertion depths and inter-electrode distances when using the high definition continuous interleaved sampling (HDCIS) and fine structure processing (FSP) speech coding strategies. Identification of intonation and speaker gender was determined and music quality rating was assessed. For intonation identification HDCIS was robust against the different electrode configurations, whereas fine structure processing showed significantly worse results when a short electrode depth was simulated. In contrast, speaker gender recognition was not affected by electrode configuration or speech coding strategy. Music quality rating was sensitive to electrode configuration. In conclusion, the three experiments revealed different outcomes, even though they all addressed the reception of F0 cues. Rapid changes in F0, as seen with intonation, were the most sensitive to electrode configurations and coding strategies. In contrast, electrode configurations and coding strategies did not show large effects when F0 information was available over a longer time period, as seen with speaker gender. Music quality relies on additional spectral cues other than F0, and was poorest when a shallow insertion was simulated.
Qi, Beier; Liu, Bo; Liu, Sha; Liu, Haihong; Dong, Ruijuan; Zhang, Ning; Gong, Shusheng
2011-05-01
To study the effect of cochlear electrode coverage and different insertion region on speech recognition, especially tone perception of cochlear implant users whose native language is Mandarin Chinese. Setting seven test conditions by fitting software. All conditions were created by switching on/off respective channels in order to simulate different insertion position. Then Mandarin CI users received 4 Speech tests, including Vowel Identification test, Consonant Identification test, Tone Identification test-male speaker, Mandarin HINT test (SRS) in quiet and noise. To all test conditions: the average score of vowel identification was significantly different, from 56% to 91% (Rank sum test, P < 0.05). The average score of consonant identification was significantly different, from 72% to 85% (ANOVNA, P < 0.05). The average score of Tone identification was not significantly different (ANOVNA, P > 0.05). However the more channels activated, the higher scores obtained, from 68% to 81%. This study shows that there is a correlation between insertion depth and speech recognition. Because all parts of the basement membrane can help CI users to improve their speech recognition ability, it is very important to enhance verbal communication ability and social interaction ability of CI users by increasing insertion depth and actively stimulating the top region of cochlear.
Problems in depth perception : perceived size and distance of familiar objects.
DOT National Transportation Integrated Search
1966-06-01
Judgments of the distance of familiar objects, especially other aircraft, are critical aspects of flight safety. In this study, the perception of distance as a function of the retinal size of a familiar object was investigated by simulating a station...
Azmat, Syed Khurram
2011-01-01
Purpose Pakistan is a patriarchal society in which male opinion leaders play an important role in determining health-seeking behaviors pertaining to family planning (FP) among their respective communities. This research focuses on cataloguing the perceptions of opinion leaders (clergymen, health professionals, and social workers) about the barriers for using services and practical solutions for promoting FP in the slums of Karachi, Pakistan. Materials and methods A qualitative study using an open-ended, semistructured interview schedule with hypothetical scenarios and in-depth interviews with a purposive sample of 45 opinion leaders (25 mosque imams/clergymen, 12 nonallopathic health professionals, and eight social workers/activists) was conducted in 2006–2007 in Karachi, Pakistan. Transcripts were coded thematically utilizing NVivo by using an adapted constant comparison analysis process as described by Strauss and Corbin. Results Seven key themes were derived from the in-depth interviews. Five themes provide insight into the opinion leaders’ perceptions of barriers to FP and modern contraception methods. Among the barriers religious taboos and cultural pressures were particularly note-worthy. Two themes offered opportunities for more effective development and implementation of FP programs. Conclusion It is evident from the study that opinion leaders in the community and the clergy lack the understanding of the importance of birth spacing. However, because they have a great deal of influence on the community at large, it is imperative to interact with them to build their capacity in order to propagate the messages of FP and improve maternal health and reproductive health in general. PMID:22247617
Design issues for stereo vision systems used on tele-operated robotic platforms
NASA Astrophysics Data System (ADS)
Edmondson, Richard; Vaden, Justin; Hyatt, Brian; Morris, Jim; Pezzaniti, J. Larry; Chenault, David B.; Tchon, Joe; Barnidge, Tracy; Kaufman, Seth; Pettijohn, Brad
2010-02-01
The use of tele-operated Unmanned Ground Vehicles (UGVs) for military uses has grown significantly in recent years with operations in both Iraq and Afghanistan. In both cases the safety of the Soldier or technician performing the mission is improved by the large standoff distances afforded by the use of the UGV, but the full performance capability of the robotic system is not utilized due to insufficient depth perception provided by the standard two dimensional video system, causing the operator to slow the mission to ensure the safety of the UGV given the uncertainty of the perceived scene using 2D. To address this Polaris Sensor Technologies has developed, in a series of developments funded by the Leonard Wood Institute at Ft. Leonard Wood, MO, a prototype Stereo Vision Upgrade (SVU) Kit for the Foster-Miller TALON IV robot which provides the operator with improved depth perception and situational awareness, allowing for shorter mission times and higher success rates. Because there are multiple 2D cameras being replaced by stereo camera systems in the SVU Kit, and because the needs of the camera systems for each phase of a mission vary, there are a number of tradeoffs and design choices that must be made in developing such a system for robotic tele-operation. Additionally, human factors design criteria drive optical parameters of the camera systems which must be matched to the display system being used. The problem space for such an upgrade kit will be defined, and the choices made in the development of this particular SVU Kit will be discussed.
ERIC Educational Resources Information Center
Jones, Tamara
This paper explores the perceptions of three rural secondary school teachers in the Riverina area of New South Wales, Australia. In-depth interviews were conducted with three secondary teachers: three male teachers aged 25, 32, and 60. The original objective of the grounded theory study was to examine the teachers' perceptions about the state's…
Living with cleft lip and palate: the treatment journey.
Alansari, Reem; Bedos, Christophe; Allison, Paul
2014-03-01
To better understand how individuals with cleft lip and palate (CLP) perceive and experience their treatment process and how these perceptions and experiences change over the life course. Qualitative in-depth semistructured interviews with 11 adults with nonsyndromal complete CLP. Individuals from three Canadian cities were recruited by convenience and theoretical sampling through AboutFace International. The number of participants was determined by the principle of theoretical saturation. The experience of individuals with CLP through the treatment process changes over the life course. In childhood and early adolescence, most individuals experience stigma, negative self-perception, and as a result were more prone to perceiving the treatment process not only as unbearably burdensome but also as fueling their feeling of "defectiveness." In adulthood, participants' self-perception improved, partly because of definitive surgical correction, leading them to realize treatment benefits and reappraise the treatment process as satisfactory rather than burdensome. Subsequently, some individuals pursued further surgeries hoping for additional psychological gains, in lieu of psychosocial interventions addressing the underpinnings of residual feelings of "defectiveness." This led to dissatisfaction and frustration when the procedures did not lead to the hoped-for psychological gains. The results emphasize the importance of self-perception in determining how participants perceive several important aspects of the treatment experience throughout the life course. Further studies should focus on how to incorporate self-perception as an important variable and outcome in the treatment process.
Nabulsi, Mona; Khalil, Yvette; Makhoul, Jihad
2011-07-01
Paediatric clinical research faces unique challenges that compromise optimal recruitment of children into clinical trials. A main barrier to enrolment of children is parental misconceptions about the research process. In developing countries, there is a knowledge gap regarding parental perceptions of and attitudes towards their children's participation in clinical trials. To explore such perceptions and attitudes in Lebanese parents. 33 in-depth interviews were conducted with parents with and without previous research experience. Interviews were tape-recorded, transcribed in colloquial Arabic, and later subjected to thematic analysis. Benefit/risk ratio assessment was a major determinant of parental consent. Fear of adverse events or painful procedures in research was a recurring theme in most interviews. Whereas perception of direct benefit to the child, trust in the physician or institution, financial gains or having a positive previous experience in research facilitated consent, a complex informed consent form and misunderstanding of the term 'randomisation' hindered parental approval of participation. Lebanese parents have perceptions of and attitudes towards children's participation in clinical trials that are similar to those reported from the industrialised world. Improving communication with parents and building trust between researchers and parents is important for successful recruitment. Investigators planning to conduct paediatric trials in developing countries need to simplify consent forms and devise new ways to explain randomisation.
"Missing pieces": exploring cardiac risk perceptions in older women.
Lefler, Leanne L; McSweeney, Jean C; Garner, Kimberly K
2013-04-01
Approximately 95% of older women have factors that put them at risk for developing cardiovascular disease, but research indicates many do not perceive themselves to be at risk. We examined older women's perceived risk for coronary heart disease (CHD) and the factors influencing their perceptions. We conducted a descriptive, qualitative study using in-depth, individual interviews and quantitative measures to assess perceived risk and risk factors. Twenty-four older African American and Caucasian women had a mean 4.46 cardiac risk factors but perceived their own CHD risk as unrealistically low at 1.95 cm (SD = 1.57, on 0-to-8 cm visual analogue scale). Narrative data clustered in themes that represented a lack of fact-based information and multiple misconceptions about CHD and prevention. Major improvements in CHD health are only achievable if risk factors are prevented. This research suggests older women have substantial needs for consistent CHD information and prevention guidance. Copyright 2013, SLACK Incorporated.
Time as a Key Topic in Health Professionals’ Perceptions of Clinical Handovers
Watson, Bernadette M.; Jones, Liz; Cretchley, Julia
2014-01-01
Clinical handovers are an essential part of the daily care and treatment of hospital patients. We invoked a language and social psychology lens to investigate how different health professional groups discussed the communication problems and strengths they experienced in handovers. We conducted in-depth interviews with three different health professional groups within a large metropolitan hospital. We used Leximancer text analytics software as a tool to analyze the data. Results showed that time was of concern to all groups in both similar and diverse ways. All professionals discussed time management, time pressures, and the difficulties of coordinating different handovers. Each professional group had its own unique perceptions and priorities about handovers. Our findings indicated that health professionals understood what was required for handover improvement but did not have the extra capacity to alter their current environment. Hospital management, with clinicians, need to implement handover schedule processes that prioritize interprofessional representation. PMID:28462291
Rasul, V H; Cheraghi, M A; Behboodi Moqadam, Z
2015-01-01
Aim: This study was aimed to explore and describe the Kurdish women's perception of cervical cancer screening. Methods: A qualitative design based on a conventional content analysis approach. Purposive sampling was applied to 19 women chosen, who had a Pap smear or refused to have one. The study was performed in the Kurdistan Region, Iraq. Semi-structure din-depth individual interviews were carried out to collect data. Results: Four main themes including conflict, belief, and awareness about cervical cancer screening and socio-cultural factors emerged during data analysis Conclusions: Cervical cancer has a high mortality rate in the developing countries. However, only a few Kurdish women participated in the cervical cancer screening in the Kurdistan Region, Iraq. Understanding the factors associated with the women's perception of cervical cancer could guide future educational planning and clinical interventions improve the cervical cancer screening.
Rasul, VH; Cheraghi, MA; Behboodi Moqadam, Z
2015-01-01
Aim:This study was aimed to explore and describe the Kurdish women’s perception of cervical cancer screening. Methods: A qualitative design based on a conventional content analysis approach. Purposive sampling was applied to 19 women chosen, who had a Pap smear or refused to have one. The study was performed in the Kurdistan Region, Iraq. Semi-structure din-depth individual interviews were carried out to collect data. Results: Four main themes including conflict, belief, and awareness about cervical cancer screening and socio-cultural factors emerged during data analysis Conclusions: Cervical cancer has a high mortality rate in the developing countries. However, only a few Kurdish women participated in the cervical cancer screening in the Kurdistan Region, Iraq. Understanding the factors associated with the women’s perception of cervical cancer could guide future educational planning and clinical interventions improve the cervical cancer screening. PMID:28255397
Solevåg, Anne Lee; Karlgren, Klas
2016-01-01
In 2011 an interprofessional educational programme called "Pediatric systematic assessment and communication for preventing emergencies" designed to increase clinical staff's competence in treating sick children was introduced in one paediatrics department in Norway. To elicit an in-depth understanding of the perceptions of clinical staff about the programme and enact adjustments according to identified enabling and hindering factors for learning, nurses and paediatricians were invited to participate in focus group interviews. The interviews were analysed by content analysis. Enabling factors for learning included improved interprofessional collaboration and positive feedback on performance. Hindering factors included perceptions that the programme was redundant and the fact that collaborating departments, such as the surgical departments, were not familiar with the programme. Peer learning, more interprofessional learning activities, and the fostering of a learning organization were suggestions for sustained learning. Based on the results of the study we have now included collaborating departments in the programme.
Nursing student perceptions of community in online learning.
Gallagher-Lepak, Susan; Reilly, Janet; Killion, Cheryl M
2009-01-01
Nursing faculty need to understand the unique aspects of online learning environments and develop new pedagogies for teaching in the virtual classroom. The concept of community is important in online learning and a strong sense of community can enhance student engagement and improve learning outcomes in online courses. Student perceptions of community in online learning environments were explored in this study. Five focus group sessions were held and online nursing students were asked to give examples of experiences related to sense of community. Fifteen major themes emerged: class structure, required participation, teamwork, technology, becoming, commonalities, disconnects, mutual exchange, online etiquette, informal discussions, aloneness, trepidation, unknowns, nonverbal communication and anonymity. Themes sorted into the categories of structural, processual and emotional factors. Theme descriptions show how sense of community can be enhanced and/or diminished in online courses. This study adds depth and detail to the limited body of research on sense of community in distance education in nursing courses.
Perceived visual speed constrained by image segmentation
NASA Technical Reports Server (NTRS)
Verghese, P.; Stone, L. S.
1996-01-01
Little is known about how or where the visual system parses the visual scene into objects or surfaces. However, it is generally assumed that the segmentation and grouping of pieces of the image into discrete entities is due to 'later' processing stages, after the 'early' processing of the visual image by local mechanisms selective for attributes such as colour, orientation, depth, and motion. Speed perception is also thought to be mediated by early mechanisms tuned for speed. Here we show that manipulating the way in which an image is parsed changes the way in which local speed information is processed. Manipulations that cause multiple stimuli to appear as parts of a single patch degrade speed discrimination, whereas manipulations that perceptually divide a single large stimulus into parts improve discrimination. These results indicate that processes as early as speed perception may be constrained by the parsing of the visual image into discrete entities.
Bereaved parents' experiences of music therapy with their terminally ill child.
Lindenfelser, Kathryn J; Grocke, Denise; McFerran, Katrina
2008-01-01
The purpose of this study was to investigate bereaved parents' experiences of music therapy with their terminally ill child. In-depth interviews were conducted with 7 bereaved parents who were recruited through a community-based palliative care program. The parent participants' experiences varied as their children who received music therapy ranged in ages from 5 months to 12 years old. The interview transcripts were analyzed using phenomenological strategies. Five global themes emerged from the analysis. These included (a) music therapy was valued as a means of altering the child's and family's perception of their situation in the midst of adversity, (b) music therapy was a significant component of remembrance, (c) music therapy was a multifaceted experience for the child and family, (d) music therapy enhanced communication and expression, and (e) parents shared perceptions of and recommendations for improving music therapy services. These emergent themes yield knowledge into the relevance of music therapy within pediatric palliative care.
Mitigation of wildfire risk by homeowners
Hannah Brenkert; Patricia Champ; Nicholas Flores
2005-01-01
In-depth interviews conducted with homeowners in Larimer County's Wildland-Urban Interface revealed that homeowners face difficult decisions regarding the implementation of wildfire mitigation measures. Perceptions of wildfire mitigation options may be as important as perceptions of wildfire risk in determining likelihood of implementation. These mitigation...
Monocular Depth Perception and Robotic Grasping of Novel Objects
2009-06-01
resulting algorithm is able to learn monocular vision cues that accurately estimate the relative depths of obstacles in a scene. Reinforcement learning ... learning still make sense in these settings? Since many of the cues that are useful for estimating depth can be re-created in synthetic images, we...supervised learning approach to this problem, and use a Markov Random Field (MRF) to model the scene depth as a function of the image features. We show
Doi, Takahiro; Fujita, Ichiro
2014-01-01
Three-dimensional visual perception requires correct matching of images projected to the left and right eyes. The matching process is faced with an ambiguity: part of one eye's image can be matched to multiple parts of the other eye's image. This stereo correspondence problem is complicated for random-dot stereograms (RDSs), because dots with an identical appearance produce numerous potential matches. Despite such complexity, human subjects can perceive a coherent depth structure. A coherent solution to the correspondence problem does not exist for anticorrelated RDSs (aRDSs), in which luminance contrast is reversed in one eye. Neurons in the visual cortex reduce disparity selectivity for aRDSs progressively along the visual processing hierarchy. A disparity-energy model followed by threshold nonlinearity (threshold energy model) can account for this reduction, providing a possible mechanism for the neural matching process. However, the essential computation underlying the threshold energy model is not clear. Here, we propose that a nonlinear modification of cross-correlation, which we term “cross-matching,” represents the essence of the threshold energy model. We placed half-wave rectification within the cross-correlation of the left-eye and right-eye images. The disparity tuning derived from cross-matching was attenuated for aRDSs. We simulated a psychometric curve as a function of graded anticorrelation (graded mixture of aRDS and normal RDS); this simulated curve reproduced the match-based psychometric function observed in human near/far discrimination. The dot density was 25% for both simulation and observation. We predicted that as the dot density increased, the performance for aRDSs should decrease below chance (i.e., reversed depth), and the level of anticorrelation that nullifies depth perception should also decrease. We suggest that cross-matching serves as a simple computation underlying the match-based disparity signals in stereoscopic depth perception. PMID:25360107
Experiencing Technology Integration in Education: Children's Perceptions
ERIC Educational Resources Information Center
Baytak, Ahmet; Tarman, Bülent; Ayas, Cemalettin
2011-01-01
The purpose of this phenomenological study was to explore the experiences of six children using technologies in their education. Data were collected via in-depth interviews, classroom observations, and home observations. The results showed that students have common perceptions toward their experience with technology integration. Furthermore, the…
Student-Athlete Wellbeing and Persistence: An In-Depth Look at Student-Athlete Perceptions
ERIC Educational Resources Information Center
Kamusoko, Sibongile D.; Pemberton, Cynthia Lee A.
2012-01-01
This study investigated student-athlete perceptions of wellbeing, delimited to satisfaction regarding Athletic Department Policies and Practices, Educational Characteristics, Institutional Facilities and Services, and intent to academically persist. The study employed quantitative and qualitative data queries. This paper reports emergent findings…
Von Rosen, Philip; Kottorp, Anders; Fridén, Cecilia; Frohm, Anna; Heijne, Annette
2018-06-01
Even though injury is common in elite sports, there is still a lack of knowledge of young athletes' injury perception both during and after injury. The aim of this mixed-method study was, therefore, to explore, in-depth, data on injury consequences and adolescent elite athletes' perceptions and experience of injury. Three hundred and forty adolescent elite athletes (age range 15-19), from 16 different sports, were bi-weekly monitored over 52 weeks using a valid questionnaire. Twenty athletes from the same cohort were interviewed in focus groups about injury experience and perceptions. The results show that the average bi-weekly prevalence of injury was 38.7% (95% CI 37.3-40.1), with 30.0% (n = 102) of the athletes injured for more than half of all reporting times. An overarching theme from the focus groups highlighted the risk among young athletes of a loss of identity while injured. The findings support several suggestions that may improve the rehabilitation process and enhance rehabilitation outcomes: (a) provide clear pathways to the medical team, (b) recognize the identity loss, (c) involve the injured athletes with the rest of the teammates and (d) educate athletes about how to interpret pain signals. Future research should explore and evaluate the effectiveness and generalization of such interventions.
Chhabra, Namrata; Kukreja, Sahiba; Chhabra, Sarah; Chhabra, Sahil; Khodabux, Sameenah; Sabane, Harshal
2017-12-01
Team-based learning (TBL) strategy has been widely adapted by medical schools all over the world, but the reports regarding the perceptions and the attitudes of faculty and undergraduate medical students towards TBL approach have been conflicting. The study aimed to introduce TBL strategy in curriculum of Biochemistry after evaluating its effectiveness through perceptions and attitudes of faculty and 1 st -year medical students. One hundred and fifty students of first professional M.B.B.S and five faculty members participated in the study. Their responses regarding perceptions and attitudes towards TBL strategy were collected using structured questionnaires, focus group discussions, and in-depth interviews. Data were analyzed using Wilcoxon signed-rank test, paired sample t -test, and Mann-Whitney U-test. Majority of the students expressed satisfaction with team approach and reported improvement in the academic scores, learning styles, and development of problem-solving, interpersonal, and professional skills. The faculty, however, recommended a modified TBL approach to benefit all sections of the students for the overall success of this intervention. TBL is an effective technique to enable the students to master the core concepts and develop professional and critical thinking skills; however, for the 1 st -year medical students, a modified TBL approach might be more appropriate for the effective outcomes.
ERIC Educational Resources Information Center
Keppens, G.; Spruyt, B.
2015-01-01
The purpose of the present study is to explore non-truanting youngsters' perceptions of truants and truancy. In-depth qualitative interviews (N: 8) are used to explore inductively the perceptions of truancy among non-truanting pupils in secondary education in Flanders (the Dutch-speaking part of Belgium). We use survey analysis (N: 3314) to assess…
Occupants' Perceptions of Amenity and Efficiency for Verification of Spatial Design Adequacy.
Lee, Sangwon; Wohn, Kwangyun
2016-01-14
The best spatial design condition to satisfy the occupancy needs of amenity and efficiency is determined through analyzing the spatial design adequacy (SDA). In this study, the relationship between the space design elements and space on future occupants' perception are analyzed. The thirty-three participants reported their self-evaluated SDA that describes the quality of eight alternative housing living rooms with different spatial factors. The occupants were guided through the perception processing elaboration in order for them to evaluate the actual perception in the real space. The findings demonstrated that the spatial size (e.g., width, depth, and height) is significantly correlated with the overall satisfaction of amenity. It is also found that the spatial shape (e.g., the width-to-depth ratio, the height-to-area ratio, and room shape) may significantly influence the overall satisfaction of efficiency. The findings also demonstrate that the causal relationship between the spatial factors and space is clearly present in the occupants' perception, reflecting the time-sequential characteristics of the actual experience divided into amenity and efficiency. This result indicates that the correlation between the spatial factors and space of SDA under the occupants' perception processing elaboration can be a useful guide to predict the occupancy satisfaction of amenity and efficiency in real spaces.
Occupants’ Perceptions of Amenity and Efficiency for Verification of Spatial Design Adequacy
Lee, Sangwon; Wohn, Kwangyun
2016-01-01
The best spatial design condition to satisfy the occupancy needs of amenity and efficiency is determined through analyzing the spatial design adequacy (SDA). In this study, the relationship between the space design elements and space on future occupants’ perception are analyzed. The thirty-three participants reported their self-evaluated SDA that describes the quality of eight alternative housing living rooms with different spatial factors. The occupants were guided through the perception processing elaboration in order for them to evaluate the actual perception in the real space. The findings demonstrated that the spatial size (e.g., width, depth, and height) is significantly correlated with the overall satisfaction of amenity. It is also found that the spatial shape (e.g., the width-to-depth ratio, the height-to-area ratio, and room shape) may significantly influence the overall satisfaction of efficiency. The findings also demonstrate that the causal relationship between the spatial factors and space is clearly present in the occupants’ perception, reflecting the time-sequential characteristics of the actual experience divided into amenity and efficiency. This result indicates that the correlation between the spatial factors and space of SDA under the occupants’ perception processing elaboration can be a useful guide to predict the occupancy satisfaction of amenity and efficiency in real spaces. PMID:26784211
Hashmi, Ahmar H; Paw, Moo Kho; Nosten, Suphak; Darakamon, Mu Chae; Gilder, Mary Ellen; Charunwatthana, Prakaykaew; Carrara, Verena I; Wickramasinghe, Kremlin; Angkurawaranon, Chaisiri; Plugge, Emma; McGready, Rose
2018-01-01
Under- and over-nutrition during pregnancy are known risk factors for pregnancy complications and adverse pregnancy and infant outcomes. Understanding perceptions around nutrition in pregnancy can create culturally appropriate interventions for improved health outcomes. A mixed-methods study was performed to explore local perceptions and practices of diet and physical activity in pregnancy in a marginalised population along the Myanmar-Thailand border. From April to July 2017, a cross-sectional survey and focus group discussions were conducted with pregnant women reporting to antenatal care; in-depth interviews were conducted with senior midwives at participating organisations along the Myanmar-Thailand border. A total of 388 pregnant women were interviewed at two clinic sites along the Myanmar-Thailand border. A high proportion of women had limited knowledge of and poor dietary practices. Consuming a sweetened drink in the last 24 hours as well as being a non-teenage, multigravida woman was significantly associated with high body mass index (BMI) compared to normal BMI. Qualitative analysis combined focus group discussions (n = 66) and in-depth interviews (n = 4) summarising emergent themes: common foods eaten or avoided and rationale; benefits of nutrition; perceptions of overweight and weight gain during pregnancy; barriers to a healthy diet; and sources of diet information. There is limited awareness about healthy diets and lifestyle in these marginalised, migrant communities along the Myanmar-Thailand border. This study suggests that simple, culturally appropriate messaging should be provided to women and communities with low health literacy to generate awareness about healthy lifestyles and their effects on pregnancy outcomes as an important element of a broader strategy to address maternal nutrition in this population. However, more studies to determine the effectiveness of a broad range of interventions in low- and middle-income countries (LMIC) are needed, especially in marginalised migrant populations.
Pseudo-color coding method for high-dynamic single-polarization SAR images
NASA Astrophysics Data System (ADS)
Feng, Zicheng; Liu, Xiaolin; Pei, Bingzhi
2018-04-01
A raw synthetic aperture radar (SAR) image usually has a 16-bit or higher bit depth, which cannot be directly visualized on 8-bit displays. In this study, we propose a pseudo-color coding method for high-dynamic singlepolarization SAR images. The method considers the characteristics of both SAR images and human perception. In HSI (hue, saturation and intensity) color space, the method carries out high-dynamic range tone mapping and pseudo-color processing simultaneously in order to avoid loss of details and to improve object identifiability. It is a highly efficient global algorithm.
Augmented Reality Imaging System: 3D Viewing of a Breast Cancer.
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.
Students' Perceptions of a "Quality" Advisory Relationship
ERIC Educational Resources Information Center
Halbert, Kelsey
2015-01-01
The current research education context in Australia is one of increased pressures for timely completion with a spotlight on the scope and depth of training and a profound increase in enrolments. These factors inevitably shape the supervision experiences of doctoral candidates. This paper discusses student perceptions of supervision. Supervision is…
Perceptions of Learning among Swiss Watch Managers
ERIC Educational Resources Information Center
Tajeddini, Kayhan
2009-01-01
Purpose: This paper aims to explore managers' perceptions of learning within a sample of Swiss watch firms. Design/methodology/approach: A purposeful (judgmental) stratified sampling method was employed, where in-depth interviews with 13 marketing managers and owners were carried out over a three-month period. Meaning units (MUs) were abstracted,…
ERIC Educational Resources Information Center
Stahnke, Rebekka; Schueler, Sven; Roesken-Winter, Bettina
2016-01-01
Research in mathematics education has investigated teachers' professional knowledge in depth, comprising two different approaches: a cognitive and a situated perspective. Linking these two perspectives leads to addressing situation-specific skills such as perception, interpretation and decision-making, indicative of revealing a teacher's knowledge…
"Some Kind of Weird, Evil Experiment": Student Perceptions of Peer Assessment
ERIC Educational Resources Information Center
Patton, Chloe
2012-01-01
This paper explores the attitudes and perceptions of three cohorts of Australian humanities and social science undergraduate students towards peer assessment. It seeks to gain a deeper understanding of local dissatisfaction with peer assessment through an in-depth analysis of students' contributions to focus group discussions. Responding to…
[Comparative analysis of light sensitivity, depth and motion perception in animals and humans].
Schaeffel, F
2017-11-01
This study examined how humans perform regarding light sensitivity, depth perception and motion vision in comparison to various animals. The parameters that limit the performance of the visual system for these different functions were examined. This study was based on literature studies (search in PubMed) and own results. Light sensitivity is limited by the brightness of the retinal image, which in turn is determined by the f‑number of the eye. Furthermore, it is limited by photon noise, thermal decay of rhodopsin, noise in the phototransduction cascade and neuronal processing. In invertebrates, impressive optical tricks have been developed to increase the number of photons reaching the photoreceptors. Furthermore, the spontaneous decay of the photopigment is lower in invertebrates at the cost of higher energy consumption. For depth perception at close range, stereopsis is the most precise but is available only to a few vertebrates. In contrast, motion parallax is used by many species including vertebrates as well as invertebrates. In a few cases accommodation is used for depth measurements or chromatic aberration. In motion vision the temporal resolution of the eye is most important. The ficker fusion frequency correlates in vertebrates with metabolic turnover and body temperature but also has very high values in insects. Apart from that the flicker fusion frequency generally declines with increasing body weight. Compared to animals the performance of the visual system in humans is among the best regarding light sensitivity, is the best regarding depth resolution and in the middle range regarding motion resolution.
The processing of linear perspective and binocular information for action and perception.
Bruggeman, Hugo; Yonas, Albert; Konczak, Jürgen
2007-04-08
To investigate the processing of linear perspective and binocular information for action and for the perceptual judgment of depth, we presented viewers with an actual Ames trapezoidal window. The display, when presented perpendicular to the line of sight, provided perspective information for a rectangular window slanted in depth, while binocular information specified a planar surface in the fronto-parallel plane. We compared pointing towards the display-edges with perceptual judgment of their positions in depth as the display orientation was varied under monocular and binocular view. On monocular trials, pointing and depth judgment were based on the perspective information and failed to respond accurately to changes in display orientation because pictorial information did not vary sufficiently to specify the small differences in orientation. For binocular trials, pointing was based on binocular information and precisely matched the changes in display orientation whereas depth judgment was short of such adjustment and based upon both binocular and perspective-specified slant information. The finding, that on binocular trials pointing was considerably less responsive to the illusion than perceptual judgment, supports an account of two separate processing streams in the human visual system, a ventral pathway involved in object recognition and a dorsal pathway that produces visual information for the control of actions. Previously, similar differences between perception and action were explained by an alternate explanation, that is, viewers selectively attend to different parts of a display in the two tasks. The finding that under monocular view participants responded to perspective information in both the action and the perception task rules out the attention-based argument.
Monocular depth perception using image processing and machine learning
NASA Astrophysics Data System (ADS)
Hombali, Apoorv; Gorde, Vaibhav; Deshpande, Abhishek
2011-10-01
This paper primarily exploits some of the more obscure, but inherent properties of camera and image to propose a simpler and more efficient way of perceiving depth. The proposed method involves the use of a single stationary camera at an unknown perspective and an unknown height to determine depth of an object on unknown terrain. In achieving so a direct correlation between a pixel in an image and the corresponding location in real space has to be formulated. First, a calibration step is undertaken whereby the equation of the plane visible in the field of view is calculated along with the relative distance between camera and plane by using a set of derived spatial geometrical relations coupled with a few intrinsic properties of the system. The depth of an unknown object is then perceived by first extracting the object under observation using a series of image processing steps followed by exploiting the aforementioned mapping of pixel and real space coordinate. The performance of the algorithm is greatly enhanced by the introduction of reinforced learning making the system independent of hardware and environment. Furthermore the depth calculation function is modified with a supervised learning algorithm giving consistent improvement in results. Thus, the system uses the experience in past and optimizes the current run successively. Using the above procedure a series of experiments and trials are carried out to prove the concept and its efficacy.
Neural correlates of monocular and binocular depth cues based on natural images: a LORETA analysis.
Fischmeister, Florian Ph S; Bauer, Herbert
2006-10-01
Functional imaging studies investigating perception of depth rely solely on one type of depth cue based on non-natural stimulus material. To overcome these limitations and to provide a more realistic and complete set of depth cues natural stereoscopic images were used in this study. Using slow cortical potentials and source localization we aimed to identify the neural correlates of monocular and binocular depth cues. This study confirms and extends functional imaging studies, showing that natural images provide a good, reliable, and more realistic alternative to artificial stimuli, and demonstrates the possibility to separate the processing of different depth cues.
Ott, Florian; Pohl, Ladina; Halfmann, Marc; Hardiess, Gregor; Mallot, Hanspeter A
2016-07-01
When estimating ego-motion in environments (e.g., tunnels, streets) with varying depth, human subjects confuse ego-acceleration with environment narrowing and ego-deceleration with environment widening. Festl, Recktenwald, Yuan, and Mallot (2012) demonstrated that in nonstereoscopic viewing conditions, this happens despite the fact that retinal measurements of acceleration rate-a variable related to tau-dot-should allow veridical perception. Here we address the question of whether additional depth cues (specifically binocular stereo, object occlusion, or constant average object size) help break the confusion between narrowing and acceleration. Using a forced-choice paradigm, the confusion is shown to persist even if unambiguous stereo information is provided. The confusion can also be demonstrated in an adjustment task in which subjects were asked to keep a constant speed in a tunnel with varying diameter: Subjects increased speed in widening sections and decreased speed in narrowing sections even though stereoscopic depth information was provided. If object-based depth information (stereo, occlusion, constant average object size) is added, the confusion between narrowing and acceleration still remains but may be slightly reduced. All experiments are consistent with a simple matched filter algorithm for ego-motion detection, neglecting both parallactic and stereoscopic depth information, but leave open the possibility of cue combination at a later stage.
Voices of Dissent: Unpacking Vietnamese International Student Experience
ERIC Educational Resources Information Center
Huong, Le; Koo, Fung Kuen; Arambewela, Rodney; Zutshi, Ambika
2017-01-01
Purpose: The purpose of this paper is to examine Vietnamese international students' experiences with the campus learning environment by analysing differences in staff and student perceptions. Design/Methodology/Approach: Two focus groups (n = 12) and ten in-depth interviews were conducted with Vietnamese students and four in-depth interviews with…
Problems in depth perception : a method of simulating objects moving in depth.
DOT National Transportation Integrated Search
1965-12-01
Equations were developed for the simulation on a screen of the movement of an object or surface toward or away from an observer by the movement of a positive photographic transparency of the object or surface away or toward a point source. The genera...
de Resende, Daniel Romeu Benchimol; Greghi, Sebastião Luiz Aguiar; Siqueira, Aline Franco; Benfatti, César Augusto Magalhães; Damante, Carla Andreotti; Ragghianti Zangrando, Mariana Schutzer
2018-04-30
This split-mouth controlled randomized clinical trial evaluated clinical and histological results of acellular dermal matrix allograft (ADM) compared to autogenous free gingival graft (FGG) for keratinized tissue augmentation. Twenty-five patients with the absence or deficiency of keratinized tissue (50 sites) were treated with FGG (control group) and ADM (test group). Clinical parameters included keratinized tissue width (KTW) (primary outcome), soft tissue thickness (TT), recession depth (RD), probing depth (PD), and clinical attachment level (CAL). Esthetic perception was evaluated by patients and by a calibrated periodontist using visual analog scale (VAS). Histological analysis included biopsies of five different patients from both test and control sites for each evaluation period (n = 25). The analysis included percentage of connective tissue components, epithelial luminal to basal surface ratio, tissue maturation, and presence of elastic fibers. Data were evaluated by ANOVA complemented by Tukey's tests (p < 0.05). After 6 months, PD and CAL demonstrated no differences between groups. ADM presented higher RD compared to FGG in all periods. Mean tissue shrinkage for control and test groups was 12.41 versus 55.7%. TT was inferior for ADM group compared to FGG. Esthetics perception by professional evaluation showed superior results for ADM. Histomorphometric analysis demonstrated higher percentage of cellularity, blood vessels, and epithelial luminal to basal surface ratio for FGG group. ADM group presented higher percentage of collagen fibers and inflammatory infiltrate. Both treatments resulted in improvement of clinical parameters, except for RD. ADM group presented more tissue shrinkage and delayed healing, confirmed histologically, but superior professional esthetic perception. This study added important clinical and histological data to contribute in the decision-making process between indication of FGG or ADM.
[Features of the electronic eikonometer for the study of binocular function].
Bourdy, C
2013-05-01
After presenting the components of this electronic eikonometer (device schematic and organizational chart) for the analysis and measurement of perceptive effects of binocular disparity, we review the specifics (tests with incorporated magnifications seen in polarized light) and the advantages of this device as compared to existing eikonometers (absence of any intermediary optical system). We provide a list of available tests in the test library and their parametric characteristics: Ogle Spatial Test for Aniseikonia, Fixation Disparity Test: binocular nonius, and Linear and Random stereoscopic tests. We develop a methodology adapted to each type of test and the manipulations to be performed by the operators and observers. We then provide some results of examinations performed with this eikonometer for a sample of observers equipped with glasses, contact lenses or implants. We propose an analysis of these various perceptive effects from experimental and theoretical studies: association between Depth, Disparity and Fusion; brief review of theoretical studies by automatic matrix calculus of retinal image size for various types of eyes: emmetropic and isometropic eyes based on various dioptric elements from Gullstrand's eye, axial anisometropia, anisometropia of conformation, aphakia resulting from these various eyes. We demonstrate the role of these studies in the analysis of subjective measurements of aniseikonia and for the choice of best correction: variations in amplitude and sign of the monocular components of the fixation disparity as a function of the viewing distance, Complexity of depth perception, according to the test used. Considering the evolution of the technology used for the realization of this prototype, we propose that this eikonometer be updated, in particular by using high-resolution flat screens, which would allow improvement and enrichment of the test library (definition, contrast and size of the observed images). Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Color appearance in stereoscopy
NASA Astrophysics Data System (ADS)
Gadia, Davide; Rizzi, Alessandro; Bonanomi, Cristian; Marini, Daniele; Galmonte, Alessandra; Agostini, Tiziano
2011-03-01
The relationship between color and lightness appearance and the perception of depth has been studied since a while in the field of perceptual psychology and psycho-physiology. It has been found that depth perception affects the final object color and lightness appearance. In the stereoscopy research field, many studies have been proposed on human physiological effects, considering e.g. geometry, motion sickness, etc., but few has been done considering lightness and color information. Goal of this paper is to realize some preliminar experiments in Virtual Reality in order to determine the effects of depth perception on object color and lightness appearance. We have created a virtual test scene with a simple 3D simultaneous contrast configuration. We have created three different versions of this scene, each with different choices of relative positions and apparent size of the objects. We have collected the perceptual responses of several users after the observation of the test scene in the Virtual Theater of the University of Milan, a VR immersive installation characterized by a semi-cylindrical screen that covers 120° of horizontal field of view from an observation distance of 3.5 m. We present a description of the experiments setup and procedure, and we discuss the obtained results.
Morphological Computation of Haptic Perception of a Controllable Stiffness Probe.
Sornkarn, Nantachai; Dasgupta, Prokar; Nanayakkara, Thrishantha
2016-01-01
When people are asked to palpate a novel soft object to discern its physical properties such as texture, elasticity, and even non-homogeneity, they not only regulate probing behaviors, but also the co-contraction level of antagonistic muscles to control the mechanical impedance of fingers. It is suspected that such behavior tries to enhance haptic perception by regulating the function of mechanoreceptors at different depths of the fingertips and proprioceptive sensors such as tendon and spindle sensors located in muscles. In this paper, we designed and fabricated a novel two-degree of freedom variable stiffness indentation probe to investigate whether the regulation of internal stiffness, indentation, and probe sweeping velocity (PSV) variables affect the accuracy of the depth estimation of stiff inclusions in an artificial silicon phantom using information gain metrics. Our experimental results provide new insights into not only the biological phenomena of haptic perception but also new opportunities to design and control soft robotic probes.
Distance and Size Perception in Astronauts during Long-Duration Spaceflight
Clément, Gilles; Skinner, Anna; Lathan, Corinna
2013-01-01
Exposure to microgravity during spaceflight is known to elicit orientation illusions, errors in sensory localization, postural imbalance, changes in vestibulo-spinal and vestibulo-ocular reflexes, and space motion sickness. The objective of this experiment was to investigate whether an alteration in cognitive visual-spatial processing, such as the perception of distance and size of objects, is also taking place during prolonged exposure to microgravity. Our results show that astronauts on board the International Space Station exhibit biases in the perception of their environment. Objects’ heights and depths were perceived as taller and shallower, respectively, and distances were generally underestimated in orbit compared to Earth. These changes may occur because the perspective cues for depth are less salient in microgravity or the eye-height scaling of size is different when an observer is not standing on the ground. This finding has operational implications for human space exploration missions. PMID:25369884
Parietal and frontal object areas underlie perception of object orientation in depth.
Niimi, Ryosuke; Saneyoshi, Ayako; Abe, Reiko; Kaminaga, Tatsuro; Yokosawa, Kazuhiko
2011-05-27
Recent studies have shown that the human parietal and frontal cortices are involved in object image perception. We hypothesized that the parietal/frontal object areas play a role in differentiating the orientations (i.e., views) of an object. By using functional magnetic resonance imaging, we compared brain activations while human observers differentiated between two object images in depth-orientation (orientation task) and activations while they differentiated the images in object identity (identity task). The left intraparietal area, right angular gyrus, and right inferior frontal areas were activated more for the orientation task than for the identity task. The occipitotemporal object areas, however, were activated equally for the two tasks. No region showed greater activation for the identity task. These results suggested that the parietal/frontal object areas encode view-dependent visual features and underlie object orientation perception. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Assessing the consequences of stigma for tuberculosis patients in urban Zambia.
Cremers, Anne Lia; de Laat, Myrthe Manon; Kapata, Nathan; Gerrets, Rene; Klipstein-Grobusch, Kerstin; Grobusch, Martin Peter
2015-01-01
Stigma is one of the many factors hindering tuberculosis (TB) control by negatively affecting hospital delay and treatment compliance. In Zambia, the morbidity and mortality due to TB remains high, despite extended public health attempts to control the epidemic and to diminish stigma. To enhance understanding of TB-related stigmatizing perceptions and to describe TB patients' experiences of stigma in order to point out recommendations to improve TB policy. We conducted a mixed method study at Kanyama clinic and surrounding areas, in Lusaka, Zambia; structured interviews with 300 TB patients, multiple in-depth interviews with 30 TB patients and 10 biomedical health workers, 3 focus group discussions with TB patients and treatment supporters, complemented by participant observation and policy analysis of the TB control program. Predictors of stigma were identified by use of multivariate regression analyses; qualitative analysis of the in-depth interviews, focus group discussions and participant observation was used for triangulation of the study findings. We focused on the 138/300 patients that described TB-related perceptions and attitudes, of whom 113 (82%) reported stigma. Stigma provoking TB conceptions were associated with human immunodeficiency virus (HIV)-infection, alleged immoral behaviour, (perceived) incurability, and (traditional) myths about TB aetiology. Consequences of stigma prevailed both among children and adults and included low self-esteem, insults, ridicule, discrimination, social exclusion, and isolation leading to a decreased quality of life and social status, non-disclosure, and/or difficulties with treatment compliance and adherence. Women had significantly more stigma-related problems than men. The findings illustrate that many TB patients faced stigma-related issues, often hindering effective TB control and suggesting that current efforts to reduce stigma are not yet optimal. The content and implementation of sensitization programs should be improved and more emphasis needs to be placed on women and children.
ERIC Educational Resources Information Center
Servos, Jennifer E.; Dewar, Brandy A.; Bosacki, Sandra L.; Coplan, Robert J.
2016-01-01
This article investigates early childhood educators' perceptions of children's gender-role play and the impact their cultural background plays in their gender identity and play behaviors. Through qualitative in-depth interviews, early childhood educators in Canada (n = 40) were asked questions relating to their experiences with children from…
Outsourcing Academic Development in Higher Education: Staff Perceptions of an International Program
ERIC Educational Resources Information Center
Dickson, Kerry; Hughes, Kate; Stephens, Bruce
2017-01-01
Increasingly, higher education support services are being outsourced. Our case study was of a program from a global, USA-based, non-profit organisation. From in-depth interviews, we investigated staff perceptions of academic development workshops and the efficacy of outsourcing to a transnational tertiary-support program. We found that…
ERIC Educational Resources Information Center
Chou, Yueh-Ching; Lu, Zxy-Yann Jane; Wang, Frank T. Y.; Lan, Chang-Fu; Lin, Li-Chan
2008-01-01
Background: No studies have ever been conducted concerning menstrual experiences among women with an intellectual disability in Taiwan. Materials and Methods: An in-depth interview was conducted at three public institutions and perceptions and experiences regarding menstruation were elicited from 55 women aged 21-65 years. Results: The…
Do We Speak the Same Language? A Study of Faculty Perceptions of Information Literacy
ERIC Educational Resources Information Center
Cope, Jonathan; Sanabria, Jesús E.
2014-01-01
The authors analyze twenty in-depth interviews with faculty members about how they perceive information literacy (IL) to examine two key factors: how disciplinary background influences conceptions of IL among faculty members in academic departments and how the instructors' perception of information literacy differs from that of professionals in…
ERIC Educational Resources Information Center
Morgan, Alistair; And Others
Students' orientations to learning, their perceptions of gain from their studies at Great Britain's Open University, and their development as learners were studied. Thirty students were followed from their first university course, the Social Science Foundation Course, through their two subsequent years of study, using in-depth interviews to…
ERIC Educational Resources Information Center
Kisanga, Felix; Mbwambo, Jessie; Hogan, Norah; Nystrom, Lennarth; Emmelin, Maria; Lindmark, Gunilla
2010-01-01
Through in-depth interviews, this study explored perceptions and experiences of key players handling child sexual offense cases in Dar es Salaam, Tanzania. The informants included public police investigators, magistrates, legal workers, and social workers working with nongovernmental organizations. The interviews were recorded, transcribed…
Bullying and Victimisation Dynamics in High School: An Exploratory Case Study
ERIC Educational Resources Information Center
Lekunze, Lucy M. George; Strom, B. Ivan
2017-01-01
Bullying is a worldwide concern and erroneous perceptions of the phenomenon could underscore unsustainable interventions. The purpose of this qualitative exploratory case study was to examine, in-depth, how some high school teachers from two schools in New Jersey perceived student bullying. The primary research question was: What perceptions do…
Adolescent Girls' Perceptions of Physical Activity: A Focus Group Study
ERIC Educational Resources Information Center
Whitehead, Sarah; Biddle, Stuart
2008-01-01
Low levels of physical activity among adolescent girls are a cause for concern. Examining girls' physical activity perceptions and motivations through in-depth qualitative research allows for greater understanding of the reasons behind their physical activity-related choices. Forty-seven girls aged 14 to 16 years participated in exploratory focus…
ERIC Educational Resources Information Center
Padron, Yolanda N.; Waxman, Hersh C.
2016-01-01
This study examined principals' knowledge and perceptions of second language programs for English language learners (ELLs) operating in their schools. An open-ended survey and in-depth interviews were used to examine elementary school principals' knowledge of the second language programs implemented at their schools. The survey asked principals…
Poor shape perception is the reason reaches-to-grasp are visually guided online.
Lee, Young-Lim; Crabtree, Charles E; Norman, J Farley; Bingham, Geoffrey P
2008-08-01
Both judgment studies and studies of feedforward reaching have shown that the visual perception of object distance, size, and shape are inaccurate. However, feedback has been shown to calibrate feedfoward reaches-to-grasp to make them accurate with respect to object distance and size. We now investigate whether shape perception (in particular, the aspect ratio of object depth to width) can be calibrated in the context of reaches-to-grasp. We used cylindrical objects with elliptical cross-sections of varying eccentricity. Our participants reached to grasp the width or the depth of these objects with the index finger and thumb. The maximum grasp aperture and the terminal grasp aperture were used to evaluate perception. Both occur before the hand has contacted an object. In Experiments 1 and 2, we investigated whether perceived shape is recalibrated by distorted haptic feedback. Although somewhat equivocal, the results suggest that it is not. In Experiment 3, we tested the accuracy of feedforward grasping with respect to shape with haptic feedback to allow calibration. Grasping was inaccurate in ways comparable to findings in shape perception judgment studies. In Experiment 4, we hypothesized that online guidance is needed for accurate grasping. Participants reached to grasp either with or without vision of the hand. The result was that the former was accurate, whereas the latter was not. We conclude that shape perception is not calibrated by feedback from reaches-to-grasp and that online visual guidance is required for accurate grasping because shape perception is poor.
D3D augmented reality imaging system: proof of concept in mammography.
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.
Illusory Distance Modulates Perceived Size of Afterimage despite the Disappearance of Depth Cues
Liu, Shengxi; Lei, Quan
2016-01-01
It is known that the perceived size of an afterimage is modulated by the perceived distance between the observer and the depth plane on which the afterimage is projected (Emmert’s law). Illusions like Ponzo demonstrate that illusory distance induced by depth cues can also affect the perceived size of an object. In this study, we report that the illusory distance not only modulates the perceived size of object’s afterimage during the presence of the depth cues, but the modulation persists after the disappearance of the depth cues. We used an adapted version of the classic Ponzo illusion. Illusory depth perception was induced by linear perspective cues with two tilted lines converging at the upper boundary of the display. Two horizontal bars were placed between the two lines, resulting in a percept of the upper bar to be farther away than the lower bar. Observers were instructed to make judgment about the relative size of the afterimage of the lower and the upper bars after adaptation. When the perspective cues and the bars were static, the illusory effect of the Ponzo afterimage is consistent with that of the traditional size-distance illusion. When the perspective cues were flickering and the bars were static, only the afterimage of the latter was perceived, yet still a considerable amount of the illusory effect was perceived. The results could not be explained by memory of a prejudgment of the bar length during the adaptation phase. The findings suggest that cooccurrences of depth cues and object may link a depth marker for the object, so that the perceived size of the object or its afterimage is modulated by feedback of depth information from higher-level visual cortex even when there is no depth cues directly available on the retinal level. PMID:27391335
NASA Astrophysics Data System (ADS)
Theadford, Brita A.
This qualitative case study examined four middle school science teachers from Southern New Jersey perceptions and reflections about their selections of instructional strategies used to teach scientific concepts to seventh and eighth grade students. They reflected upon their pedagogy by reviewing videotaped lessons, reflective journaling, and participating in in-depth interviews. The findings in this study indicated that reflecting upon instruction contributes to the knowledge base of teaching, improves teachers' individual practices, and helps practitioners become deliberate about their instructional practices. Teacher should have opportunities to observe, investigate and practice using components they perceive as useful instructional strategies to teach scientific concepts to middle school students. When teachers engage in reflection, pedagogical strategies transform and teachers lean toward choosing instructional strategies that are less teacher-centered toward that of more student-centered. In conclusion, it is evident that engaging in student-centered dialogue, argumentation, and researched-based projects improved the way students learned. The participants found that constructivist, hands-on inquiry and reasoning, are skills that middle school students can readily engage in and students can develop skills that help them to think and act more like scientist.
NASA Astrophysics Data System (ADS)
Anantanyu, S.; Suwarto; Suminah
2018-03-01
Empowerment is a strategy to develop and build economy and community in both physically and mentally. One effort is to help generate a plan for community development in disaster-prone areas. For that, this study aims to develop farmers profile, to describe farmer perception towards farming effort and to formulate the empowerment strategies in the development of sustainable livelihoods in disaster prone areas. This study uses mixed methods. Farmers population use in this study were live in two villages of landslides prone areas, that are Beruk and Wonorejo which belongs Jatiyoso Subdistrict Karanganyar regency (Central Java). In depth structured interview was conducted to 150 farmers under Focus Group Discussion (FGD) followed with. data analysis using SWOT analysis. The results showed level of farm management is in anxiety level, perception of farmers toward the availability of agricultural inputs is at a reasonable level and the agricultural information becomes the reduction factors. The result of QSPM matrix calculation through SWOT analysis on livelihood of agricultural, resulting some strategy according to the priority level that are development of conservation farming, strengthening the farmers capacity in agricultural products processing, strengthening farmer groups and improving the performance of agriculture extensionist.
Assessing a VR-based learning environment for anatomy education.
Hoffman, H; Murray, M; Hettinger, L; Viirre, E
1998-01-01
The purpose of the research proposed herein is to develop an empirical, methodological tool for the assessment of visual depth perception in virtual environments (VEs). Our goal is to develop and employ a behaviorally-based method for assessing the impact of VE design features on the perception of visual depth as indexed by the performance of fundamental perceptual-motor activities. Specifically, in this experiment we will assess the affect of two dimensions of VE system design--(1) viewing condition or "level of immersion", and (2) layout/design of the VE--on the performance of an engaging, game-like task. The characteristics of the task to be employed are as follows--(1) it places no demands on cognition in the form of problem solving, retrieval of previously learned information, or other analytic activity in order to assure that (2) variations in task performance can be exclusively attributed to the extent to which the experimental factors influence visual depth perception. Subjects' performance will be assessed in terms of the speed and accuracy of task performance, as well as underlying dimensions of performance such as workload, fatigue, and physiological well being (i.e., cybersickness). The results of this experiment will provide important information on the effect of VE immersion and other VE design issues on human perception and performance. Further development, refinement, and validation of this behaviorally-based methodology will be pursued to provide user-centered design criteria for the design and use of VE systems.
Norhayati, Mohd Noor; Nik Hazlina, Nik Hussain; Asrenee, Ab Razak; Sulaiman, Zaharah
2017-06-15
Maternal mortality has been the main way of ascertaining the outcome of maternal and obstetric care. However, maternal morbidities occur more frequently than maternal deaths; therefore, maternal near miss was suggested as a more useful indicator for the evaluation and improvement of maternal health services. Our study aimed to explore the experiences of women with maternal near miss and their perception of the quality of care in Kelantan, Malaysia. A qualitative phenomenological approach with in-depth interview method was conducted in two tertiary hospitals in Kelantan, Malaysia. All women admitted to labour room, obstetrics and gynaecology wards and intensive care units in 2014 were screened for the presence of any vital organ dysfunction or failure based on the World Health Organization criteria for maternal near miss. Pregnancy irrespective of the gestational age was included. Women younger than 18 years old, with psychiatric disorder and beyond 42 days of childbirth were excluded. Thirty women who had experienced maternal near miss events were included in the analysis. All were Malays between the ages of 22 and 45. Almost all women (93.3%) had secondary and tertiary education and 63.3% were employed. The women's perceptions of the quality of their care were influenced by the competency and promptness in the provision of care, interpersonal communication, information-sharing and the quality of physical resources. The predisposition to seek healthcare was influenced by costs, self-attitude and beliefs. Self-appraisal of maternal near miss, their perception of the quality of care, their predisposition to seek healthcare and the social support received were the four major themes that emerged from the experiences and perceptions of women with maternal near miss. The women with maternal near miss viewed their experiences as frightening and that they experienced other negative emotions and a sense of imminent death. The factors influencing women's perceptions of quality of care should be of concern to those seeking to improve services at healthcare facilities. The addition of a maternal near miss case review programme, allows for understanding on the factors related to providing care or to the predisposition to seek care; if addressed, may improve future healthcare and patient outcomes.
Edge-Region Grouping in Figure-Ground Organization and Depth Perception
ERIC Educational Resources Information Center
Palmer, Stephen E.; Brooks, Joseph L.
2008-01-01
Edge-region grouping (ERG) is proposed as a unifying and previously unrecognized class of relational information that influences figure-ground organization and perceived depth across an edge. ERG occurs when the edge between two regions is differentially grouped with one region based on classic principles of similarity grouping. The ERG hypothesis…
Health perceptions of Mexican American women.
Mendelson, Cindy
2002-07-01
This article describes the health perceptions of a sample of moderately to highly acculturated Mexican American women. Using an ethnographic design, the author interviewed 13 women to determine their health perceptions. The interviews were guided by the domains of health described in the World Health Organization (WHO) definition of health. Three broad categories of health perceptions were identified: the physical body, the emotional component, and finding balance. With the addition of a spiritual component, the WHO definition was a useful tool for uncovering health perceptions. The process of in-depth ethnographic interviewing provided a contextual view of health in which the complexity of intrafamilial relationships was revealed, as were the importance of spirituality as a coping mechanism and the perception of health as an integrated, holistic experience.
Young people's perception of sexual and reproductive health services in Kenya.
Godia, Pamela M; Olenja, Joyce M; Hofman, Jan J; van den Broek, Nynke
2014-04-15
Addressing the Sexual and Reproductive Health (SRH) needs of young people remains a big challenge. This study explored experiences and perceptions of young people in Kenya aged 10-24 with regard to their SRH needs and whether these are met by the available healthcare services. 18 focus group discussions and 39 in-depth interviews were conducted at health care facilities and youth centres across selected urban and rural settings in Kenya. All interviews were tape recorded and transcribed. Data was analysed using the thematic framework approach. Young people's perceptions are not uniform and show variation between boys and girls as well as for type of service delivery. Girls seeking antenatal care and family planning services at health facilities characterise the available services as good and staff as helpful. However, boys perceive services at health facilities as designed for women and children, and therefore feel uncomfortable seeking services. At youth centres, young people value the non-health benefits including availability of recreational facilities, prevention of idleness, building of confidence, improving interpersonal communication skills, vocational training and facilitation of career progression. Providing young people with SRH information and services through the existing healthcare system, presents an opportunity that should be further optimised. Providing recreational activities via youth centres is reported by young people themselves to not lead to increased uptake of SRH healthcare services. There is need for more research to evaluate how perceived non-health benefits young people do gain from youth centres could lead to improved SRH of young people.
Nnko, Soori; Bukenya, Dominic; Kavishe, Bazil Balthazar; Biraro, Samuel; Peck, Robert; Kapiga, Saidi; Grosskurth, Heiner; Seeley, Janet
2015-01-01
Research has shown that health system utilization is low for chronic diseases (CDs) other than HIV. We describe the knowledge and perceptions of CDs identified from rural and urban communities in north-west Tanzania and southern Uganda. Data were collected through a quantitative population survey, a quantitative health facility survey and focus group discussions (FGDs) and in-depth interviews (IDIs) in subgroups of population survey participants. The main focus of this paper is the findings from the FGDs and IDIs. We conducted 24 FGDs, involving approximately 180 adult participants and IDIs with 116 participants (≥18 years). CDs studied included: asthma/chronic obstructive lung disease (COPD), diabetes, epilepsy, hypertension, cardiac failure and HIV- related disease. The understanding of most chronic conditions involved a combination of biomedical information, gleaned from health facility visits, local people who had suffered from a complaint or knew others who had and beliefs drawn from information shared in the community. The biomedical contribution shows some understanding of the aetiology of a condition and the management of that condition. However, local beliefs for certain conditions (such as epilepsy) suggest that biomedical treatment may be futile and therefore work counter to biomedical prescriptions for management. Current perceptions of selected CDs may represent a barrier that prevents people from adopting efficacious health and treatment seeking behaviours. Interventions to improve this situation must include efforts to improve the quality of existing health services, so that people can access relevant, reliable and trustworthy services.
Kudoh, Nobuo
2005-01-01
Walking without vision to previously viewed targets was compared with visual perception of allocentric distance in two experiments. Experimental evidence had shown that physically equal distances in a sagittal plane on the ground were perceptually underestimated as compared with those in a frontoparallel plane, even under full-cue conditions. In spite of this perceptual anisotropy of space, Loomis et al (1992 Journal of Experimental Psychology. Human Perception and Performance 18 906-921) found that subjects could match both types of distances in a blind-walking task. In experiment 1 of the present study, subjects were required to reproduce the extent of allocentric distance between two targets by either walking towards the targets, or by walking in a direction incompatible with the locations of the targets. The latter condition required subjects to derive an accurate allocentric distance from information based on the perceived locations of the two targets. The walked distance in the two conditions was almost identical whether the two targets were presented in depth (depth-presentation condition) or in the frontoparallel plane (width-presentation condition). The results of a perceptual-matching task showed that the depth distances had to be much greater than the width distances in order to be judged to be equal in length (depth compression). In experiment 2, subjects were required to reproduce the extent of allocentric distance from the viewing point by blindly walking in a direction other than toward the targets. The walked distance in the depth-presentation condition was shorter than that in the width-presentation condition. This anisotropy in motor responses, however, was mainly caused by apparent overestimation of length oriented in width, not by depth compression. In addition, the walked distances were much better scaled than those in experiment 1. These results suggest that the perceptual and motor systems share a common representation of the location of targets, whereas a dissociation in allocentric distance exists between the two systems in full-cue conditions.
Malfliet, Anneleen; Kregel, Jeroen; Meeus, Mira; Roussel, Nathalie; Danneels, Lieven; Cagnie, Barbara; Dolphens, Mieke; Nijs, Jo
2018-05-01
Available evidence favors the use of pain neuroscience education (PNE) in patients with chronic pain. However, PNE trials are often limited to small sample sizes and, despite the current digital era, the effects of blended-learning PNE (ie, the combination of online digital media with traditional educational methods) have not yet been investigated. The study objective was to examine whether blended-learning PNE is able to improve disability, catastrophizing, kinesiophobia, and illness perceptions. This study was a 2-center, triple-blind randomized controlled trial (participants, statistician, and outcome assessor were masked). The study took place at university hospitals in Ghent and Brussels, Belgium. Participants were 120 people with nonspecific chronic spinal pain (ie, chronic neck pain and low back pain). The intervention was 3 sessions of PNE or biomedically focused back/neck school education (addressing spinal anatomy and physiology). Measurements were self-report questionnaires (Pain Disability Index, Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, Illness Perception Questionnaire, and Pain Vigilance and Awareness Questionnaire). None of the treatment groups showed a significant change in the perceived disability (Pain Disability Index) due to pain (mean group difference posteducation: 1.84; 95% CI = -2.80 to 6.47). Significant interaction effects were seen for kinesiophobia and several subscales of the Illness Perception Questionnaire, including negative consequences, cyclical time line, and acute/chronic time line. In-depth analysis revealed that only in the PNE group were these outcomes significantly improved (9% to 17% improvement; 0.37 ≤ Cohen d ≥ 0.86). Effect sizes are small to moderate, which might raise the concern of limited clinical utility; however, changes in kinesiophobia exceed the minimal detectable difference. PNE should not be used as the sole treatment modality but should be combined with other treatment strategies. Blended-learning PNE was able to improve kinesiophobia and illness perceptions in participants with chronic spinal pain. As effect sizes remained small to medium, PNE should not be used as a sole treatment but rather should be used as a key element within a comprehensive active rehabilitation program. Future studies should compare the effects of blended-learning PNE with offline PNE and should consider cost-effectiveness.
Songnian, Zhao; Qi, Zou; Chang, Liu; Xuemin, Liu; Shousi, Sun; Jun, Qiu
2014-04-23
How it is possible to "faithfully" represent a three-dimensional stereoscopic scene using Cartesian coordinates on a plane, and how three-dimensional perceptions differ between an actual scene and an image of the same scene are questions that have not yet been explored in depth. They seem like commonplace phenomena, but in fact, they are important and difficult issues for visual information processing, neural computation, physics, psychology, cognitive psychology, and neuroscience. The results of this study show that the use of plenoptic (or all-optical) functions and their dual plane parameterizations can not only explain the nature of information processing from the retina to the primary visual cortex and, in particular, the characteristics of the visual pathway's optical system and its affine transformation, but they can also clarify the reason why the vanishing point and line exist in a visual image. In addition, they can better explain the reasons why a three-dimensional Cartesian coordinate system can be introduced into the two-dimensional plane to express a real three-dimensional scene. 1. We introduce two different mathematical expressions of the plenoptic functions, Pw and Pv that can describe the objective world. We also analyze the differences between these two functions when describing visual depth perception, that is, the difference between how these two functions obtain the depth information of an external scene.2. The main results include a basic method for introducing a three-dimensional Cartesian coordinate system into a two-dimensional plane to express the depth of a scene, its constraints, and algorithmic implementation. In particular, we include a method to separate the plenoptic function and proceed with the corresponding transformation in the retina and visual cortex.3. We propose that size constancy, the vanishing point, and vanishing line form the basis of visual perception of the outside world, and that the introduction of a three-dimensional Cartesian coordinate system into a two dimensional plane reveals a corresponding mapping between a retinal image and the vanishing point and line.
2014-01-01
Background How it is possible to “faithfully” represent a three-dimensional stereoscopic scene using Cartesian coordinates on a plane, and how three-dimensional perceptions differ between an actual scene and an image of the same scene are questions that have not yet been explored in depth. They seem like commonplace phenomena, but in fact, they are important and difficult issues for visual information processing, neural computation, physics, psychology, cognitive psychology, and neuroscience. Results The results of this study show that the use of plenoptic (or all-optical) functions and their dual plane parameterizations can not only explain the nature of information processing from the retina to the primary visual cortex and, in particular, the characteristics of the visual pathway’s optical system and its affine transformation, but they can also clarify the reason why the vanishing point and line exist in a visual image. In addition, they can better explain the reasons why a three-dimensional Cartesian coordinate system can be introduced into the two-dimensional plane to express a real three-dimensional scene. Conclusions 1. We introduce two different mathematical expressions of the plenoptic functions, P w and P v that can describe the objective world. We also analyze the differences between these two functions when describing visual depth perception, that is, the difference between how these two functions obtain the depth information of an external scene. 2. The main results include a basic method for introducing a three-dimensional Cartesian coordinate system into a two-dimensional plane to express the depth of a scene, its constraints, and algorithmic implementation. In particular, we include a method to separate the plenoptic function and proceed with the corresponding transformation in the retina and visual cortex. 3. We propose that size constancy, the vanishing point, and vanishing line form the basis of visual perception of the outside world, and that the introduction of a three-dimensional Cartesian coordinate system into a two dimensional plane reveals a corresponding mapping between a retinal image and the vanishing point and line. PMID:24755246
Chhabra, Namrata; Kukreja, Sahiba; Chhabra, Sarah; Chhabra, Sahil; Khodabux, Sameenah; Sabane, Harshal
2017-01-01
Background: Team-based learning (TBL) strategy has been widely adapted by medical schools all over the world, but the reports regarding the perceptions and the attitudes of faculty and undergraduate medical students towards TBL approach have been conflicting. Aim: The study aimed to introduce TBL strategy in curriculum of Biochemistry after evaluating its effectiveness through perceptions and attitudes of faculty and 1st-year medical students. Materials and Methods: One hundred and fifty students of first professional M.B.B.S and five faculty members participated in the study. Their responses regarding perceptions and attitudes towards TBL strategy were collected using structured questionnaires, focus group discussions, and in-depth interviews. Data were analyzed using Wilcoxon signed-rank test, paired sample t-test, and Mann–Whitney U-test. Results: Majority of the students expressed satisfaction with team approach and reported improvement in the academic scores, learning styles, and development of problem-solving, interpersonal, and professional skills. The faculty, however, recommended a modified TBL approach to benefit all sections of the students for the overall success of this intervention. Conclusion: TBL is an effective technique to enable the students to master the core concepts and develop professional and critical thinking skills; however, for the 1st-year medical students, a modified TBL approach might be more appropriate for the effective outcomes. PMID:29344463
Advanced maternal age and risk perception: A qualitative study
2012-01-01
Background Advanced maternal age (AMA) is associated with several adverse pregnancy outcomes, hence these pregnancies are considered to be “high risk.” A review of the empirical literature suggests that it is not clear how women of AMA evaluate their pregnancy risk. This study aimed to address this gap by exploring the risk perception of pregnant women of AMA. Methods A qualitative descriptive study was undertaken to obtain a rich and detailed source of explanatory data regarding perceived pregnancy risk of 15 women of AMA. The sample was recruited from a variety of settings in Winnipeg, Canada. In-depth interviews were conducted with nulliparous women aged 35 years or older, in their third trimester, and with singleton pregnancies. Interviews were recorded and transcribed verbatim, and content analysis was used to identify themes and categories. Results Four main themes emerged: definition of pregnancy risk, factors influencing risk perception, risk alleviation strategies, and risk communication with health professionals. Conclusions Several factors may influence women's perception of pregnancy risk including medical risk, psychological elements, characteristics of the risk, stage of pregnancy, and health care provider’s opinion. Understanding these influential factors may help health professionals who care for pregnant women of AMA to gain insight into their perspectives on pregnancy risk and improve the effectiveness of risk communication strategies with this group. PMID:22988825
ERIC Educational Resources Information Center
el Moussaoui, Nabila; Braster, Sjaak
2011-01-01
We explored the perceptions of children's cognitive development among Moroccan Arabic and Berber immigrant mothers who cannot read, who are less educated, middle educated or highly educated in the Netherlands. A series of in-depth interviews was conducted with 22 mothers with young children (mean age = 5 years and 6 months). Qualitative data…
Advanced ESL Students' Prior EFL Education and Their Perceptions of Oral Corrective Feedback
ERIC Educational Resources Information Center
Lee, Eun Jeong
2016-01-01
The author in this study examines how advanced-level adult English as a Second Language (ESL) students' previous English as a Foreign Language (EFL) classroom experiences influence their perceptions of their teachers' oral corrective feedback (CF). It uses in-depth qualitative data to characterize the participants' prior English learning, and to…
ERIC Educational Resources Information Center
Li, Zhi; Sun, Emily; Strawser, Cassandra J.; Spiegel, Ariana; Klein, Brennan; Durgin, Frank H.
2013-01-01
Two experiments are reported concerning the perception of ground extent to discover whether prior reports of anisotropy between frontal extents and extents in depth were consistent across different measures (visual matching and pantomime walking) and test environments (outdoor environments and virtual environments). In Experiment 1 it was found…
ERIC Educational Resources Information Center
Deng, Liang-Yu F.
2012-01-01
This study explored what Taiwanese parents would educate their children about peace and what children retained from parental teaching, as well as children's reported communication with parents about peace. In-depth interviews were conducted with 60 parents and one of their children. Based on the perceptions of children, the most influential…
Perspectives on HIV/AIDS Stigma and Discrimination: Voices of Some Young People in Ghana
ERIC Educational Resources Information Center
Oduro, Georgina Yaa; Otsin, Mercy
2013-01-01
This paper examines Ghanaian young people's perceptions of the determinants of HIV- and AIDS-related stigma and discrimination, and how these perceptions may influence the de-stigmatisation process. Drawing on findings from an in-depth, multi-method qualitative study involving 104 school and street young people aged between 14 and 19 years, the…
ERIC Educational Resources Information Center
Burke, Lisa; Hsieh, Wu-Ying; Lopez-Reyna, Norma; Servilio, Kathryn
2016-01-01
The purpose of this qualitative study was to describe the perceptions of general education middle school social studies teachers related to their teaching practices and the inclusion of students with Autism Spectrum Disorder (ASD) in their classrooms. More specifically, an in-depth exploration of general education social studies teachers'…
ERIC Educational Resources Information Center
Shriver, Thomas E.; Webb, Gary R.
2009-01-01
We use in-depth interviews, participant observation, and document analysis to examine perceptions of environmental health and justice among Native Americans in a rural Oklahoma community. Residents live near the Continental Carbon Company, which manufactures a rubber compound know as "carbon black." Ponca tribal members believe their…
The Seeds of Discontent: Examining Youth Perceptions of Higher Education in Syria
ERIC Educational Resources Information Center
Buckner, Elizabeth
2013-01-01
This article examines young Syrians' perceptions of higher education after the 2001 reforms, which expanded access to higher education and permitted the establishment of private universities. Data come from in-depth interviews conducted with 22 Syrians residing in Damascus, aged 18-32 in 2009. Analysis indicates youth are critical of the higher…
ERIC Educational Resources Information Center
Goldman, Juliette D. G.; Bode, Andrew
2012-01-01
Many children raised in orphanages suffered ongoing child abuse and neglect including sexual abuse, and nearly all were denied an adequate education. This paper explores adult females' perceptions of the impacts on their education of child sexual abuse they suffered while living in orphanages in Australia. In-depth qualitative and anonymous…
Buried by Autism: Older Parents' Perceptions of Autism
ERIC Educational Resources Information Center
Hines, Monique; Balandin, Susan; Togher, Leanne
2012-01-01
In this study, we explored older parents' perceptions of their adult sons and daughters with autism in order to gain insights into how parents' beliefs about autism may influence their coping. Narrative analysis of in-depth interviews held with 16 parents aged 60 years and older of adults with autism revealed that these parents perceived that…
ERIC Educational Resources Information Center
Langan, Debra; Schott, Nicole; Wykes, Timothy; Szeto, Justin; Kolpin, Samantha; Lopez, Carla; Smith, Nathan
2016-01-01
Faculty frequently express concerns about students' personal use of information and communication technologies in today's university classrooms. As a requirement of a graduate research methodology course in a university in Ontario, Canada, the authors conducted qualitative research to gain an in-depth understanding of students' perceptions of this…
ERIC Educational Resources Information Center
Herrmann, Kim Jesper
2014-01-01
This study examines differences in university students' approaches to learning when attending tutorials as well as variation in students' perceptions of tutorials as an educational arena. In-depth qualitative analysis of semi-structured interviews with undergraduates showed how surface and deep approaches to learning were revealed in the…
ERIC Educational Resources Information Center
Torrens Armstrong, Anna M.; McCormack Brown, Kelli R.; Brindley, Roger; Coreil, Jeannine; McDermott, Robert J.
2011-01-01
Background: This study explored school personnel's perceptions of school refusal, as it has been described as a "common educational and public health problem" that is less tolerated due to increasing awareness of the potential socioeconomic consequences of this phenomenon. Methods: In-depth interviews were conducted with school personnel…
Teachers' Perceptions, Attitudes and Feelings towards Pupils of Roma Origin
ERIC Educational Resources Information Center
Zachos, Dimitris T.
2017-01-01
In this paper, the focus is on schools' responses to multiculturalism. We present a research project that was designed to explore feelings, perceptions and attitudes of teachers towards pupils of Roma origin in two different Greek schools. Our research strategy involved case studies and in-depth semi-structured interview was our main research…
Perception of Spiritual Health: A Qualitative Content Analysis in Iranian Older Adults
ERIC Educational Resources Information Center
Zibad, Hosein Ajam; Foroughan, Mahshid; Shahboulaghi, Farahnaz Mohammadi; Rafiey, Hassan; Rassouli, Maryam
2017-01-01
The present study was performed with the aim to explain older people's perceptions of spiritual health. It was conducted using the conventional content analysis method. Twelve individuals aged 60 years or older with normal cognition participated in the study using purposive sampling. Data were collected by in-depth interviews. Data analysis…
ERIC Educational Resources Information Center
Brydges, Colton; Mkandawire, Paul
2017-01-01
This article examines the perceptions of inclusive education in Lagos, Nigeria, based upon in-depth interviews conducted with students with visual impairments during the month of July 2013. The results and discussions are situated within critical disability theory. Despite decades of inclusive education policies, the findings of the study show…
The moon illusion: a test of the vestibular hypothesis under monocular viewing conditions.
Carter, D S
1977-12-01
The results of earlier monocular experiments on the moon illusion have been either negative or confounded. To test the role of vestibular function, 24 subjects made forced-choice distance comparisons between stimuli mounted in translucent tubes. The stimulus tube for standard distance could be positioned in three viewing angles (45 degrees up, horizontal, and 45 degrees down). A comparison tube adjustable for distance was mounted horizontally. There was a greater perception of depth in the downward looking condition. The relatively weak effects are discussed in terms of a two-hypothesis explanation of the real-life moon illusion and the poor cues for depth perception in monocular viewing.
Stereomotion speed perception is contrast dependent
NASA Technical Reports Server (NTRS)
Brooks, K.
2001-01-01
The effect of contrast on the perception of stimulus speed for stereomotion and monocular lateral motion was investigated for successive matches in random-dot stimuli. The familiar 'Thompson effect'--that a reduction in contrast leads to a reduction in perceived speed--was found in similar proportions for both binocular images moving in depth, and for monocular images translating laterally. This result is consistent with the idea that the monocular motion system has a significant input to the stereomotion system, and dominates the speed percept for approaching motion.
Using virtual reality to analyze sports performance.
Bideau, Benoit; Kulpa, Richard; Vignais, Nicolas; Brault, Sébastien; Multon, Franck; Craig, Cathy
2010-01-01
Improving performance in sports can be difficult because many biomechanical, physiological, and psychological factors come into play during competition. A better understanding of the perception-action loop employed by athletes is necessary. This requires isolating contributing factors to determine their role in player performance. Because of its inherent limitations, video playback doesn't permit such in-depth analysis. Interactive, immersive virtual reality (VR) can overcome these limitations and foster a better understanding of sports performance from a behavioral-neuroscience perspective. Two case studies using VR technology and a sophisticated animation engine demonstrate how to use information from visual displays to inform a player's future course of action.
Villa-Torres, Laura; Fleming, Paul J; Barrington, Clare
2015-02-01
The promotor de salud, or community health worker (CHW) role, is highly feminized and little is known about how men view their participation in CHW programs. We conducted in-depth interviews with Latino men in North Carolina to explore this gap. We used systematic coding and display procedures informed by Grounded Theory to analyze the data. Men described their communities as lacking cohesion, making integration of Latino immigrants difficult. Most did not consider themselves leaders or feel they had leaders in their communities. Their perceptions of the feminized CHW role as well as the volunteer or low-paid nature of CHW work conflicted with men's provider role. They also did not think they could perform the CHW role because they lacked education, skills, and broad networks. Efforts to increase male participation in CHW programs in new Latino immigrant destinations will need to understand and address these gender and migration-related dynamics in order to engage both women and men in improving the health of their communities.
Retention in HIV care depends on patients' perceptions of the clinic experience.
Wessinger, Matthew H; Hennink, Monique M; Kaiser, Bonnie N; Mangal, Jed P; Gokhale, Runa H; Ruchin, Lauren; Moanna, Abeer; Rimland, David; Farber, Eugene W; Marconi, Vincent C
2017-10-01
Institutional barriers in HIV primary care settings can contribute substantially to disparities in retention in HIV treatment and HIV-related outcomes. This qualitative study compared the perceptions of clinic experiences of persons living with HIV (PLWH) in a Veterans Affairs HIV primary care clinic setting who were retained in care with the experiences of those who were not retained in care. Qualitative data from 25 in-depth interviews were analyzed to identify facilitators and barriers to retention in HIV care. Results showed that participants not retained in care experienced barriers to retention involving dissatisfaction with clinic wait times, low confidence in clinicians, and customer service concerns. For participants retained in care, patience with procedural issues, confidence in clinicians, and interpersonal connections were factors that enhanced retention despite the fact that these participants recognized the same barriers as those who were not retained in care. These findings can inform interventions aimed at improving retention in HIV care.
Leading God's People: Perceptions of Influence Among African-American Pastors.
Harmon, Brook E; Strayhorn, Shaila; Webb, Benjamin L; Hébert, James R
2018-01-31
Religious leaders, particularly African-American pastors, are believed to play a key role in addressing health disparities. Despite the role African-American pastors may play in improving health, there is limited research on pastoral influence. The purpose of this study was to examine African-American pastors' perceptions of their influence in their churches and communities. In-depth interviews were conducted with 30 African-American pastors and analyzed using a grounded theory approach. Three themes emerged: the historical role of the church; influence as contextual, with pastors using comparisons with other pastors to describe their ability to be influential; and a reciprocal relationship existing such that pastors are influenced by factors such as God and their community while these factors also aid them in influencing others. A conceptual model of pastoral influence was created using data from this study and others to highlight factors that influence pastors, potential outcomes and moderators as well as the reciprocal nature of pastoral influence.
Indoor vs. Outdoor Depth Perception for Mobile Augmented Reality
2009-03-01
International Symposium on Mixed and Augmented Reality, pages 77–86, Sept. 2008. [12] M. A. Livingston, J. E. Swan II, J. L. Gabbard , T. H. Höllerer, D. Hix...D. Brown, Y. Baillot, J. L. Gabbard , and D. Hix. A perceptual matching technique for depth judgments in optical, see-through augmented reality. In
The impact of occupation on child health in a Palestinian refugee camp.
Basak, Polly
2012-12-01
This article focuses on child health in the Palestinian refugee camp of Dheisheh in the West Bank region of the Occupied Palestinian Territories. Thirty in-depth interviews were carried out with parents to determine their perceptions of their children's health. The questions related to physical, mental and social well-being, access to health facilities, factors that were likely to hinder health and measures that could be implemented to improve child health. The study was carried out prior to and during the Gaza War in December 2008 that resulted in the deaths of 1380 Palestinians including 431 children and 112 women [1]. The effects of occupation, conflict and being a refugee had a detrimental impact on perceptions of health. Interviewees revealed that their perceptions of their children's health were determined by the camp's conditions, the current economic climate, past and current political conflict and financial and social restrictions. The understanding of being healthy incorporated physical and mental health as well as social well-being. As a result, 70% of interviewees deemed that their children were not in good health. This finding accelerated to 100% after the Gaza War, showing the negative effect war has on health perceptions. Findings showed that perceptions of physical health are very much interlinked with mental well-being and parents' perceptions of their children's health, and are closely related to their state of mental health. Consequently, a clear correlation can be discerned between the ongoing occupation and its detrimental effects on mental health. Therapeutic and preventive health programmes such as child therapy and stress management that have already been implemented by the Gaza Community Mental Health Programme would be highly beneficial to both children and adults in Dheisheh refugee camp.
What is the experience of national quality campaigns? Views from the field.
Bradley, Elizabeth H; Nembhard, Ingrid M; Yuan, Christina T; Stern, Amy F; Curtis, Jeptha P; Nallamothu, Brahmajee K; Brush, John E; Krumholz, Harlan M
2010-12-01
To identify key characteristics of a national quality campaign that participants viewed as effective, to understand mechanisms by which the campaign influenced hospital practices, and to elucidate contextual factors that modified the perceived influence of the campaign on hospital improvements. In-depth interviews, hospital surveys, and Health Quality Alliance data. We conducted a qualitative study using in-depth interviews with clinical and administrative staff (N = 99) at hospitals reporting strong influence (n = 6) as well as hospitals reporting limited influence (n = 6) of the Door-to-Balloon (D2B) Alliance, a national quality campaign to improve heart attack care. We analyzed these qualitative data as well as changes in hospital use of recommended strategies reported through a hospital survey and changes in treatment times using Health Quality Alliance data. In-depth, open-ended interviews; hospital survey. Key characteristics of the national quality campaign viewed as enhancing its effectiveness were as follows: credibility of the recommendations, perceived simplicity of the recommendations, alignment with hospitals' strategic goals, practical implementation tools, and breadth of the network of peer hospitals in the D2B Alliance. Perceived mechanisms of the campaign's influence included raising awareness and influencing goals, fostering strategy adoption, and influencing aspects of organizational culture. Modifying contextual factors included perceptions about current performance and internal championship for the recommended changes. The impact of national quality campaigns may depend on both campaign design features and on the internal environment of participating hospitals. © Health Research and Educational Trust.
Lightness Constancy in Surface Visualization
Szafir, Danielle Albers; Sarikaya, Alper; Gleicher, Michael
2016-01-01
Color is a common channel for displaying data in surface visualization, but is affected by the shadows and shading used to convey surface depth and shape. Understanding encoded data in the context of surface structure is critical for effective analysis in a variety of domains, such as in molecular biology. In the physical world, lightness constancy allows people to accurately perceive shadowed colors; however, its effectiveness in complex synthetic environments such as surface visualizations is not well understood. We report a series of crowdsourced and laboratory studies that confirm the existence of lightness constancy effects for molecular surface visualizations using ambient occlusion. We provide empirical evidence of how common visualization design decisions can impact viewers’ abilities to accurately identify encoded surface colors. These findings suggest that lightness constancy aids in understanding color encodings in surface visualization and reveal a correlation between visualization techniques that improve color interpretation in shadow and those that enhance perceptions of surface depth. These results collectively suggest that understanding constancy in practice can inform effective visualization design. PMID:26584495
Performing under pressure: Exploring the psychological state underlying clutch performance in sport.
Swann, Christian; Crust, Lee; Jackman, Patricia; Vella, Stewart A; Allen, Mark S; Keegan, Richard
2017-12-01
Clutch performance is improved performance under pressure. However, little research has examined the psychological state experienced by athletes in these situations. Therefore, this study qualitatively examined the subjective experience underlying clutch performance across a range of sports (e.g., team, individual) and standards (Olympic to recreational athletes). Sixteen athletes (M age = 27.08 years; SD = 6.48) took part in in-depth, semi-structured interviews primarily after an exceptional performance (M = 4.38 days later; SD = 3.14). Data were analysed inductively and thematically. Clutch states involved 12 characteristics, including heightened and deliberate concentration, intense effort, and heightened awareness, which distinguished the experience of clutch from other optimal psychological states such as flow. Other characteristics, such as perceptions of control, were also reported and supported previous experimental research on clutch. These findings present in-depth qualitative insights into the psychological state underlying clutch performance, and are discussed in relation to the existing literature on optimal psychological states in sport.
ERIC Educational Resources Information Center
Atici, Meral
2007-01-01
The purpose of this study is to identify student teachers' perceptions of classroom management and methods for dealing with misbehaviour. In-depth interviews with nine student teachers at Cukurova University (CU) in Turkey have been conducted twice, prior to and at the end of their teaching practice. Instructional management, behaviour management,…
Focus Groups to Explore the Perceptions of Older Adults on a Pedometer-Based Intervention
ERIC Educational Resources Information Center
Jones, David B.; Richeson, Nancy E.; Croteau, Karen A.; Farmer, Bonnie Cashin
2009-01-01
Focus group methodology was used to explore in depth the perceptions of older adults who had participated in a 12-week pedometer-based intervention. Nineteen women and 8 men, ages 55-86 years, volunteered to take part in the focus groups following participation in the intervention. Four focus groups of six to eight participants were scheduled at…
ERIC Educational Resources Information Center
Green, Wendy
2007-01-01
This paper investigates the approaches taken to essay writing by five Asian international students at an Australian university. Analysis of their in-depth interviews reveals links between their perceptions of learning, their perceptions of essay writing, their motivation for completing the task, and their awareness of the structural conventions of…
ERIC Educational Resources Information Center
Brittian, Aerika S.; Lewin, Nina; Norris, Shane A.
2013-01-01
This study examined South African youths' perceptions of religion during a period of social and economic transition. In-depth interviews were conducted with 55 Black South African youth (age 18) living in the Johannesburg-Soweto metropolitan area. Data were analyzed in a manner consistent with grounded theory methodology and structural coding.…
ERIC Educational Resources Information Center
Berlin, Donna F.; White, Arthur L.
2012-01-01
The purpose of this study is to provide an in-depth analysis of attitudes and perceptions related to the integration of mathematics, science, and technology education of preservice teachers preparing to teach STEM disciplines. Longitudinal data by individual cohort and across 7 years of the Integrated Mathematics, Science, and Technology (MSAT)…
ERIC Educational Resources Information Center
Chakraborti-Ghosh, Sumita
2008-01-01
The purpose of this study was to explore the perceptions, identification and treatment of students with behavior problems or disorders in India and the United States. Participants in the study were students and teachers in the United States and India. A qualitative approach included in-depth interviews and participant observations. These were…
ERIC Educational Resources Information Center
Dapi, Leonie N.; Omoloko, Cecile; Janlert, Urban; Dahlgren, Lars; Haglin, Lena
2007-01-01
Objective: To investigate factors influencing rural and urban adolescents' food perceptions during a time of nutritional transition in Cameroon, Africa. Design: Qualitative in-depth interviews. Settings: Yaounde urban and Bandja rural areas. Participants: Fifteen adolescents 12 to 15 years old purposely selected from schools in urban and rural…
ERIC Educational Resources Information Center
Shange, Thembeka G. C.
2015-01-01
With the increase in student enrolments in higher education, which has resulted in changes to student profiles, academic development has become important in terms of students' success. This article is a report on a qualitative study that used in-depth interviews to investigate the perceptions of Engineering students and staff to academic…
ERIC Educational Resources Information Center
Muszkat-Barkan, Michal
2015-01-01
The aim of this qualitative study is to describe teachers' perceptions and roles in prayer education in TALI day schools in Israel, using in-depth oral Interviews, written questionnaires and written materials of the schools' network. Two educational ideologies were identified: Belonging to the Jewish collective and Personal-spiritual ideology.…
Morphological Computation of Haptic Perception of a Controllable Stiffness Probe
Sornkarn, Nantachai; Dasgupta, Prokar; Nanayakkara, Thrishantha
2016-01-01
When people are asked to palpate a novel soft object to discern its physical properties such as texture, elasticity, and even non-homogeneity, they not only regulate probing behaviors, but also the co-contraction level of antagonistic muscles to control the mechanical impedance of fingers. It is suspected that such behavior tries to enhance haptic perception by regulating the function of mechanoreceptors at different depths of the fingertips and proprioceptive sensors such as tendon and spindle sensors located in muscles. In this paper, we designed and fabricated a novel two-degree of freedom variable stiffness indentation probe to investigate whether the regulation of internal stiffness, indentation, and probe sweeping velocity (PSV) variables affect the accuracy of the depth estimation of stiff inclusions in an artificial silicon phantom using information gain metrics. Our experimental results provide new insights into not only the biological phenomena of haptic perception but also new opportunities to design and control soft robotic probes. PMID:27257814
van Hamersveld, Koen T; den Bakker, Emil; Nyamtema, Angelo S; van den Akker, Thomas; Mfinanga, Elirehema H; van Elteren, Marianne; van Roosmalen, Jos
2012-05-01
To explore barriers to and solutions for effective implementation of obstetric audit at Saint Francis Designated District Hospital in Ifakara, Tanzania, where audit results have been disappointing 2 years after its introduction. Qualitative study involving participative observation of audit sessions, followed by 23 in-depth interviews with health workers and managers. Knowledge and perceptions of audit were assessed and suggestions for improvement of the audit process explored. During the observational period, audit sessions were held irregularly and only when the head of department of obstetrics and gynaecology was available. Cases with evident substandard care factors were audited. In-depth interviews revealed inadequate knowledge of the purpose of audit, despite the fact that participants regarded obstetric audit as a potentially useful tool. Insufficient staff commitment, managerial support and human and material resources were mentioned as reasons for weak involvement of health workers and poor implementation of recommendations resulting from audit. Suggestions for improvement included enhancing feedback to all staff and managers to attend sessions and assist with the effectuation of audit recommendations. Obstetric staff in Ifakara see audit as an important tool for quality improvement. They recognise, however, that in their own situation, insufficient staff commitment and poor managerial support are barriers to successful implementation. They suggested training in concept and principles of audit as well as strengthening feedback of audit outcomes, to achieve structural health care improvements through audit. © 2012 Blackwell Publishing Ltd.
Human Factors in Virtual Reality Development
NASA Technical Reports Server (NTRS)
Kaiser, Mary K.; Proffitt, Dennis R.; Null, Cynthia H. (Technical Monitor)
1995-01-01
This half-day tutorial will provide an overview of basic perceptual functioning as it relates to the design of virtual environment systems. The tutorial consists of three parts. First, basic issues in visual perception will be presented, including discussions of the visual sensations of brightness and color, and the visual perception of depth relationships in three-dimensional space (with a special emphasis on motion -specified depth). The second section will discuss the importance of conducting human-factors user studies and evaluations. Examples and suggestions on how best to get help with user studies will be provided. Finally, we will discuss how, by drawing on their complementary competencies, perceptual psychologists and computer engineers can work as a team to develop optimal VR systems, technologies, and techniques.
The role of stereopsis (three-dimensional vision) in dentistry: review of the current literature.
Syrimi, M; Ali, N
2015-05-22
Clinical dental work is placing increasing demands on a clinician's vision as new techniques that require fine detail become more common. High hand-eye coordination requires good visual acuity as well as other psychological and neurological qualities such as stereopsis. Stereopsis (three-dimensional vision) is the highest form of depth perception obtained by visual disparity of images formed in the retinas of two eyes. It is believed to confer functional benefits on everyday tasks such as hand-eye coordination. Although its role in depth perception has long been established, little is known regarding the importance of stereopsis in dentistry. This article reviews the role of stereopsis in everyday life and the available literature on the importance of stereopsis in dentistry.
Multimedia article. The keys to the new laparoscopic world Thumbs up! knot and Tornado knot.
Uchida, K; Haruta, N; Okajima, M; Matsuda, M; Yamamoto, M
2005-06-01
Most laparoscopic surgeons feel some anxiety when performing intracorporeal knotting with conventional techniques [1, 2]. Two factors contribute to this anxiety. The first is the necessity of recognizing three dimensions on a two-dimensional monitor. The conventional intracorporeal knotting techniques make loops by twisting the thread with a second pair of forceps. This necessitates cooperative movement of both hands, with the added difficulties of depth perception. Regular touch confirmations reduce problems with depth perception. However, touch confirmation is more complicated in laparoscopic surgery than in laparotomy. The second problem is that tied loops can come loose and escape the instruments, especially with hard thread. This is not only stressful but also increases operation time.
Nilagiri, Vinay Kumar; Metlapally, Sangeetha; Kalaiselvan, Parthasarathi; Schor, Clifton M; Bharadwaj, Shrikant R
2018-04-01
This study showed an improvement in three-dimensional depth perception of subjects with bilateral and unilateral keratoconus with rigid gas-permeable (RGP) contact lens wear, relative to spectacles. This novel information will aid clinicians to consider RGP contact lenses as a management modality in keratoconic patients complaining of depth-related difficulties with their spectacles. The aim of this study was to systematically compare changes in logMAR acuity and stereoacuity from best-corrected spherocylindrical spectacles to RGP contact lenses in bilateral and unilateral keratoconus vis-à-vis age-matched control subjects. Monocular and binocular logMAR acuity and random-dot stereoacuity were determined in subjects with bilateral (n = 30; 18 to 24 years) and unilateral (n = 10; 18 to 24 years) keratoconus and 20 control subjects using standard psychophysical protocols. Median (25th to 75th interquartile range) monocular (right eye) and binocular logMAR acuity and stereoacuity improved significantly from spectacles to RGP contact lenses in the bilateral keratoconus cohort (P < .001). Only monocular logMAR acuity of affected eye and stereoacuity improved from spectacles to RGP contact lenses in the unilateral keratoconus cohort (P < .001). There was no significant change in the binocular logMAR acuity from spectacles to RGP contact lenses in the unilateral keratoconus cohort. The magnitude of improvement in binocular logMAR acuity and stereoacuity was also greater for the bilateral compared with the unilateral keratoconus cohort. All outcome measures of cases with RGP contact lenses remained poorer than control subjects (P < .001). Binocular resolution and stereoacuity improve from spectacles to RGP contact lenses in bilateral keratoconus, whereas only stereoacuity improves from spectacles to RGP contact lenses in unilateral keratoconus. The magnitude of improvement in visual performance is greater for the binocular compared with the unilateral keratoconus cohort.
The venetian-blind effect: a preference for zero disparity or zero slant?
Vlaskamp, Björn N. S.; Guan, Phillip; Banks, Martin S.
2013-01-01
When periodic stimuli such as vertical sinewave gratings are presented to the two eyes, the initial stage of disparity estimation yields multiple solutions at multiple depths. The solutions are all frontoparallel when the sinewaves have the same spatial frequency; they are all slanted when the sinewaves have quite different frequencies. Despite multiple solutions, humans perceive only one depth in each visual direction: a single frontoparallel plane when the frequencies are the same and a series of small slanted planes—Venetian blinds—when the frequencies are quite different. These percepts are consistent with a preference for solutions that minimize absolute disparity or overall slant. The preference for minimum disparity and minimum slant are identical for gaze at zero eccentricity; we dissociated the predictions of the two by measuring the occurrence of Venetian blinds when the stimuli were viewed in eccentric gaze. The results were generally quite consistent with a zero-disparity preference (Experiment 1), but we also observed a shift toward a zero-slant preference when the edges of the stimulus had zero slant (Experiment 2). These observations provide useful insights into how the visual system constructs depth percepts from a multitude of possible depths. PMID:24273523
The venetian-blind effect: a preference for zero disparity or zero slant?
Vlaskamp, Björn N S; Guan, Phillip; Banks, Martin S
2013-01-01
When periodic stimuli such as vertical sinewave gratings are presented to the two eyes, the initial stage of disparity estimation yields multiple solutions at multiple depths. The solutions are all frontoparallel when the sinewaves have the same spatial frequency; they are all slanted when the sinewaves have quite different frequencies. Despite multiple solutions, humans perceive only one depth in each visual direction: a single frontoparallel plane when the frequencies are the same and a series of small slanted planes-Venetian blinds-when the frequencies are quite different. These percepts are consistent with a preference for solutions that minimize absolute disparity or overall slant. The preference for minimum disparity and minimum slant are identical for gaze at zero eccentricity; we dissociated the predictions of the two by measuring the occurrence of Venetian blinds when the stimuli were viewed in eccentric gaze. The results were generally quite consistent with a zero-disparity preference (Experiment 1), but we also observed a shift toward a zero-slant preference when the edges of the stimulus had zero slant (Experiment 2). These observations provide useful insights into how the visual system constructs depth percepts from a multitude of possible depths.
Feasibility of community neonatal death audits in rural Uttar Pradesh, India.
Patel, Z; Kumar, V; Singh, P; Singh, V; Yadav, R; Baqui, A H; Santosham, M; Awasthi, S; Singh, J V; Darmstadt, G L
2007-09-01
Medical audit is a widely promoted strategy in hospitals, but experience within community settings is scant. Community neonatal death audit is a form of audit, which involves a systematic analysis of the quality of care provided in the home, danger sign recognition and care seeking decision making for neonatal illness. This research was conducted in Uttar Pradesh, India, to investigate the feasibility and cultural acceptability of community neonatal death audits. During November-December 2004, we conducted three in-depth interviews with family members of deceased neonates, and six focus group discussions with family and community members. Three approaches were evaluated: in-depth interview with the family before engaging them in an audit with the community; preliminary meeting to build rapport with the family and community before conducting an audit; and audit with the family and community in a single focus group. Approaches were interactive processes, involving the community, to identify avoidable factors in a particular death and discuss solutions. Carried out in a culturally sensitive and non-punitive manner, community neonatal death audit was found to be acceptable and feasible. All approaches provoked formal investigation by community members, and stimulated sharing of views, leading to the self-discovery that community perception was a cumulatively amplified effect of individual perceptions. Presence of an educated/experienced community member or health worker served as a catalyst. No one optimal approach was identified. Community neonatal audit is an acceptable approach that shows promise as an effective intervention for improving neonatal health outcomes.
Stereoscopy in cinematographic synthetic imagery
NASA Astrophysics Data System (ADS)
Eisenmann, Jonathan; Parent, Rick
2009-02-01
In this paper we present experiments and results pertaining to the perception of depth in stereoscopic viewing of synthetic imagery. In computer animation, typical synthetic imagery is highly textured and uses stylized illumination of abstracted material models by abstracted light source models. While there have been numerous studies concerning stereoscopic capabilities, conventions for staging and cinematography in stereoscopic movies have not yet been well-established. Our long-term goal is to measure the effectiveness of various cinematography techniques on the human visual system in a theatrical viewing environment. We would like to identify the elements of stereoscopic cinema that are important in terms of enhancing the viewer's understanding of a scene as well as providing guidelines for the cinematographer relating to storytelling. In these experiments we isolated stereoscopic effects by eliminating as many other visual cues as is reasonable. In particular, we aim to empirically determine what types of movement in synthetic imagery affect the perceptual depth sensing capabilities of our viewers. Using synthetic imagery, we created several viewing scenarios in which the viewer is asked to locate a target object's depth in a simple environment. The scenarios were specifically designed to compare the effectiveness of stereo viewing, camera movement, and object motion in aiding depth perception. Data were collected showing the error between the choice of the user and the actual depth value, and patterns were identified that relate the test variables to the viewer's perceptual depth accuracy in our theatrical viewing environment.
ERIC Educational Resources Information Center
Risner, Doug; Godfrey, Heidi; Simmons, Linda C.
2004-01-01
The ways in which seven private sector dance professionals in the United States perceive the impact of sexuality in contemporary culture and the choices that they make for their own schools of dance because of these perceptions are explored. This study was conducted through in-depth interviews and a survey instrument. The participants' narratives…
An Emphasis on Perception: Teaching Image Formation Using a Mechanistic Model of Vision.
ERIC Educational Resources Information Center
Allen, Sue; And Others
An effective way to teach the concept of image is to give students a model of human vision which incorporates a simple mechanism of depth perception. In this study two almost identical versions of a curriculum in geometrical optics were created. One used a mechanistic, interpretive eye model, and in the other the eye was modeled as a passive,…
1991-05-10
extrasensory areas, where the transfer is mediated by activity in the hippocampus. One of the objectives of this proposed research is to determine...Visual Perception : The Neurophysiological Foundations, Academic, New York, 1989. .] M. Livingstone and D. Ilubel. Segregation of form, color, movement...and depth: Anatomy, physiology, and perception . Science, 240:740-749, 1988. 56: M. S. Livingstone and D. H. Hubel. Anatomy and physiology of a color
ERIC Educational Resources Information Center
Usfar, Avita A.; Iswarawanti, Dwi N.; Davelyna, Devy; Dillon, Drupadi
2010-01-01
Objective: To examine caregivers' perceptions and practices related to food and personal hygiene and its association with diarrhea in children 6 to 36 months of age who suffered recurrent diarrhea. Design: This qualitative study, conducted in March and April 2006, used both in-depth interviews and direct observation data. Setting: Urban Tangerang,…
ERIC Educational Resources Information Center
Schafer, Tim; Amoateng, Geoffrey; Wrycraft, Nick
2009-01-01
This paper presents the results of research into GP perceptions of the impact of on-site counselling on general practice. The research is part of a larger evaluation of a local enhanced primary care mental service. The initial survey and in-depth interviews with GPs reported here focused on the pre-existing counselling service. The results suggest…
Nuriddin, Azizeh; Jalloh, Mohamed F; Meyer, Erika; Bunnell, Rebecca; Bio, Franklin A; Jalloh, Mohammad B; Sengeh, Paul; Hageman, Kathy M; Carroll, Dianna D; Conteh, Lansana; Morgan, Oliver
2018-01-01
Social mobilisation and risk communication were essential to the 2014-2015 West African Ebola response. By March 2015, >8500 Ebola cases and 3370 Ebola deaths were confirmed in Sierra Leone. Response efforts were focused on 'getting to zero and staying at zero'. A critical component of this plan was to deepen and sustain community engagement. Several national quantitative studies conducted during this time revealed Ebola knowledge, personal prevention practices and traditional burial procedures improved as the outbreak waned, but healthcare system challenges were also noted. Few qualitative studies have examined these combined factors, along with survivor stigma during periods of ongoing transmission. To obtain an in-depth understanding of people's perceptions, attitudes and behaviours associated with Ebola transmission risks, 27 focus groups were conducted between April and May 2015 with adult Sierra Leonean community members on: trust in the healthcare system, interactions with Ebola survivors, impact of Ebola on lives and livelihood, and barriers and facilitators to ending the outbreak. Participants perceived that as healthcare practices and facilities improved, so did community trust. Resource management remained a noted concern. Perceptions of survivors ranged from sympathy and empathy to fear and stigmatisation. Barriers included persistent denial of ongoing Ebola transmission, secret burials and movement across porous borders. Facilitators included personal protective actions, consistent messaging and the inclusion of women and survivors in the response. Understanding community experiences during the devastating Ebola epidemic provides practical lessons for engaging similar communities in risk communication and social mobilisation during future outbreaks and public health emergencies.
Baker, Dian L; Miller, Elizabeth; Dang, Michelle T; Yaangh, Chiem-Seng; Hansen, Robin L
2010-12-01
Southeast Asian American families are underrepresented among recipients of special education and social services for people with developmental disabilities. Our aims were to use a community-based participatory research approach to examine Hmong and Mien families' perceptions of developmental disabilities and understand barriers to and facilitators of service provision among families experiencing developmental disabilities. We describe here a case study of a successful attempt to engage marginalized and underserved communities to understand their needs to improve access and services for persons with developmental disabilities. We conducted 2 focus groups with 11 key informants and 1 focus group with 10 family members of persons with developmental disabilities, as well as in-depth interviews with 3 shamans. Using a thematic analysis approach, we coded notes and transcripts to assess community members' understanding of developmental disabilities, experiences negotiating educational and health care systems, and barriers to high-quality care. A predominant theme was the perception that reliance on governmental support services is not appropriate. Common barriers identified included lack of accurate information, language difficulties, lack of trust, and limited outreach. These perceptions and barriers, combined with limited access to services, interfere with community acceptance and use of available support services. Despite these barriers, participants indicated that with education, outreach, and culturally responsive support, families would likely accept services. Community-based participatory methods are effective for eliciting root causes of health inequities in marginalized communities. Outreach to community-based organizations and an inclusive research practice identified social and cultural reasons for low service uptake and provided a pathway for the community to improve services for persons with developmental disabilities.
Determining the disease management process for epileptic patients: A qualitative study.
Hosseini, Nazafarin; Sharif, Farkhondeh; Ahmadi, Fazlollah; Zare, Mohammad
2016-01-01
Epilepsy exposes patients to many physical, social, and emotional challenges. Thus, it seems to portray a complex picture and needs holistic care. Medical treatment and psychosocial part of epilepsy remain central to managing and improving the patient's qualify of life through team efforts. Some studies have shown the dimensions of self-management, but its management process of epilepsy patients, especially in Iran, is not clear. This study aimed to determine the disease management process in patients with epilepsy in Iran. This qualitative approach and grounded theory study was conducted from January 2009 to February 2012 in Isfahan city (Iran). Thirty-two participants were recruited by the goal-oriented, and snowball sample selection and theoretical sampling methods. After conducting a total of 43 in-depth interviews with the participants, the researchers reached data saturation. Data were analyzed using Strauss and Corbin method. With a focus on disease management process, researchers found three main themes and seven sub-themes as a psychosocial process (PSP). The main themes were: perception of threat to self-identity, effort to preserve self-identity, and burn out. The psychosocial aspect of the disease generated one main variable "the perception of identity loss" and one central variable "searching for self-identity." Participants attributed threat to self-identity and burn out to the way their disease was managed requiring efforts to preserve their identity. Recommendations consist of support programs and strategies to improve the public perception of epilepsy in Iran, help patients accept their condition and preserve self-identity, and most importantly, enhance medical management of epilepsy.
Bedside teaching-making it an effective instructional tool.
Khan, Ishtiaq Ali
2014-01-01
Bedside teaching is defined as any teaching in the presence of patient and is the core teaching strategy during the clinical years of a medical student. Although it is considered the most effective method to teach clinical and communication skills but its quality is deteriorating with the passage of time. The objective of this study is to explore faculty's perceptions about bedside teaching. This study was conducted in clinical disciplines of Ayub Medical College and hospital Abbottabad, Pakistan from January 2012 to July 2012. Pragmatic paradigm was selected to gather both quantitative and qualitative information. Data was collected sequentially to validate findings. Perceptions of all professors of clinical subjects about bed side teaching were recorded on a close-ended structured questionnaire. Then in-depth interviews were taken from 5 professors using an open ended questionnaire. Quantitative data was analysed using, SPSS-16. Qualitative research data was analysed through content analysis. Out of 20 professors of clinical departments 18 agreed to respond to the questionnaire assessing their perceptions about bed side teaching. Non-existence of bedside teaching curriculum, lack of discipline in students and faculty, lack of accountability, poor job satisfaction and low salary were identified as major factors responsible for decline in quality of bedside teaching. Most of them advocated that curriculum development, planning bedside teaching, implementation of discipline and accountability, improved job satisfaction and performance based promotions will improve quality of clinical teaching. Curriculum development for bedside teaching, institutional discipline, application of best planning strategies, performance based appraisal of faculty and good job satisfaction can make bedside teaching an effective instructional tool.
Parallax scanning methods for stereoscopic three-dimensional imaging
NASA Astrophysics Data System (ADS)
Mayhew, Christopher A.; Mayhew, Craig M.
2012-03-01
Under certain circumstances, conventional stereoscopic imagery is subject to being misinterpreted. Stereo perception created from two static horizontally separated views can create a "cut out" 2D appearance for objects at various planes of depth. The subject volume looks three-dimensional, but the objects themselves appear flat. This is especially true if the images are captured using small disparities. One potential explanation for this effect is that, although three-dimensional perception comes primarily from binocular vision, a human's gaze (the direction and orientation of a person's eyes with respect to their environment) and head motion also contribute additional sub-process information. The absence of this information may be the reason that certain stereoscopic imagery appears "odd" and unrealistic. Another contributing factor may be the absence of vertical disparity information in a traditional stereoscopy display. Recently, Parallax Scanning technologies have been introduced, which provide (1) a scanning methodology, (2) incorporate vertical disparity, and (3) produce stereo images with substantially smaller disparities than the human interocular distances.1 To test whether these three features would improve the realism and reduce the cardboard cutout effect of stereo images, we have applied Parallax Scanning (PS) technologies to commercial stereoscopic digital cinema productions and have tested the results with a panel of stereo experts. These informal experiments show that the addition of PS information into the left and right image capture improves the overall perception of three-dimensionality for most viewers. Parallax scanning significantly increases the set of tools available for 3D storytelling while at the same time presenting imagery that is easy and pleasant to view.
Holistic processing of impossible objects: evidence from Garner's speeded-classification task.
Freud, Erez; Avidan, Galia; Ganel, Tzvi
2013-12-18
Holistic processing, the decoding of the global structure of a stimulus while the local parts are not explicitly represented, is a basic characteristic of object perception. The current study was aimed to test whether such a representation could be created even for objects that violate fundamental principles of spatial organization, namely impossible objects. Previous studies argued that these objects cannot be represented holistically in long-term memory because they lack coherent 3D structure. Here, we utilized Garner's speeded classification task to test whether the perception of possible and impossible objects is mediated by similar holistic processing mechanisms. To this end, participants were asked to make speeded classifications of one object dimension while an irrelevant dimension was kept constant (baseline condition) or when this dimension varied (filtering condition). It is well accepted that ignoring the irrelevant dimension is impossible when holistic perception is mandatory, thus the extent of Garner interference in performance between the baseline and filtering conditions serves as an index of holistic processing. Critically, in Experiment 1, similar levels of Garner interference were found for possible and impossible objects implying holistic perception of both object types. Experiment 2 extended these results and demonstrated that even when depth information was explicitly processed, participants were still unable to process one dimension (width/depth) while ignoring the irrelevant dimension (depth/width, respectively). The results of Experiment 3 replicated the basic pattern found in Experiments 1 and 2 using a novel set of object exemplars. In Experiment 4, we used possible and impossible versions of the Penrose triangles in which information about impossibility is embedded in the internal elements of the objects which participant were explicitly asked to judge. As in Experiments 1-3, similar Garner interference was found for possible and impossible objects. Taken together, these findings emphasize the centrality of holistic processing style in object perception and suggest that it applies even for atypical stimuli such as impossible objects. Copyright © 2013 Elsevier B.V. All rights reserved.
Nguyen, Jillian; Majmudar, Ushma V; Ravaliya, Jay H; Papathomas, Thomas V; Torres, Elizabeth B
2015-01-01
Recently, movement variability has been of great interest to motor control physiologists as it constitutes a physical, quantifiable form of sensory feedback to aid in planning, updating, and executing complex actions. In marked contrast, the psychological and psychiatric arenas mainly rely on verbal descriptions and interpretations of behavior via observation. Consequently, a large gap exists between the body's manifestations of mental states and their descriptions, creating a disembodied approach in the psychological and neural sciences: contributions of the peripheral nervous system to central control, executive functions, and decision-making processes are poorly understood. How do we shift from a psychological, theorizing approach to characterize complex behaviors more objectively? We introduce a novel, objective, statistical framework, and visuomotor control paradigm to help characterize the stochastic signatures of minute fluctuations in overt movements during a visuomotor task. We also quantify a new class of covert movements that spontaneously occur without instruction. These are largely beneath awareness, but inevitably present in all behaviors. The inclusion of these motions in our analyses introduces a new paradigm in sensory-motor integration. As it turns out, these movements, often overlooked as motor noise, contain valuable information that contributes to the emergence of different kinesthetic percepts. We apply these new methods to help better understand perception-action loops. To investigate how perceptual inputs affect reach behavior, we use a depth inversion illusion (DII): the same physical stimulus produces two distinct depth percepts that are nearly orthogonal, enabling a robust comparison of competing percepts. We find that the moment-by-moment empirically estimated motor output variability can inform us of the participants' perceptual states, detecting physiologically relevant signals from the peripheral nervous system that reveal internal mental states evoked by the bi-stable illusion. Our work proposes a new statistical platform to objectively separate changes in visual perception by quantifying the unfolding of movement, emphasizing the importance of including in the motion analyses all overt and covert aspects of motor behavior.
Jeffs, Eunice; Ream, Emma; Shewbridge, Amanda; Cowan-Dickie, Siobhan; Crawshaw, Diana; Huit, Martine; Wiseman, Theresa
2016-02-01
The aim of this study was to identify factors influencing patient perception of success and benefit with self-management of breast cancer-related lymphoedema (BCRL) and explore how patients decide whether their swollen limb has improved or deteriorated. This qualitative study used a Grounded Theory approach. Twenty-one women in the BCRL self-management phase participated in one in-depth interview exploring their experience and perspective on self-managing their BCRL. Seven enablers and blocks to self-management were identified: routine, recognising benefit of self-management and consequences of non-treatment, owning treatment, knowledge and understanding, problem-solving, time required for treatment and aesthetics of hosiery. Women determined treatment outcome by monitoring size, appearance, texture and internal sensations within the affected arm. Women who participated in this study showed varying degrees of acceptance and adjustment to life with lymphoedema. This appears to directly impact their ability to self-manage lymphoedema. Lymphoedema practitioners and oncology nurses have a valuable role providing knowledge and support to patients transitioning to independent self-care. A better understanding of factors facilitating patients to become experts in their condition may improve longer term outcomes and reduce cost pressures on lymphoedema services. Copyright © 2015 Elsevier Ltd. All rights reserved.
Qualitative study to explore stakeholder perceptions related to road safety in Hyderabad, India.
Tetali, Shailaja; Lakshmi, J K; Gupta, Shivam; Gururaj, G; Wadhwaniya, Shirin; Hyder, Adnan A
2013-12-01
The Bloomberg Philanthropies Global Road Safety Programme in India focuses on reduction of drink driving and increase in helmet usage in the city of Hyderabad. During the early stages of implementation, perceptions of stakeholders on road safety were explored as part of the monitoring and evaluation process for a better understanding of areas for improving road safety in Hyderabad. Fifteen in-depth interviews with government officials, subject experts, and road traffic injury victims, and four focus group discussions with trauma surgeons, medical interns, nurses, and taxi drivers were conducted, analysed manually, and presented as themes. Respondents found Hyderabad unsafe for road-users. Factors such as inadequate traffic laws, gaps in enforcement, lack of awareness, lack of political will, poor road engineering, and high-risk road users were identified as threats to road safety. The responsibility for road safety was assigned to both individual road-users and the government, with the former bearing the responsibility for safe traffic behaviour, and the latter for infrastructure provision and enforcement of regulations. The establishment of a lead agency to co-ordinate awareness generation, better road engineering, and stricter enforcement of traffic laws with economic and non-economic penalties for suboptimal traffic behaviour, could facilitate improved road safety in Hyderabad. Copyright © 2013 Elsevier Ltd. All rights reserved.
Samsiah, A; Othman, Noordin; Jamshed, Shazia; Hassali, Mohamed Azmi
2016-01-01
To explore and understand participants' perceptions and attitudes towards the reporting of medication errors (MEs). A qualitative study using in-depth interviews of 31 healthcare practitioners from nine publicly funded, primary care clinics in three states in peninsular Malaysia was conducted for this study. The participants included family medicine specialists, doctors, pharmacists, pharmacist assistants, nurses and assistant medical officers. The interviews were audiotaped and transcribed verbatim. Analysis of the data was guided by the framework approach. Six themes and 28 codes were identified. Despite the availability of a reporting system, most of the participants agreed that MEs were underreported. The nature of the error plays an important role in determining the reporting. The reporting system, organisational factors, provider factors, reporter's burden and benefit of reporting also were identified. Healthcare practitioners in primary care clinics understood the importance of reporting MEs to improve patient safety. Their perceptions and attitudes towards reporting of MEs were influenced by many factors which affect the decision-making process of whether or not to report. Although the process is complex, it primarily is determined by the severity of the outcome of the errors. The participants voluntarily report the errors if they are familiar with the reporting system, what error to report, when to report and what form to use.
Jilcott, Stephanie B; Laraia, Barbara A; Evenson, Kelly R; Ammerman, Alice S
2009-01-01
Qualitative research on food choice has rarely focused on individuals' perceptions of the community food environment. Women remain gatekeepers of the family diet and food purchasing. Therefore we assessed midlife, Southern women's perceptions of the food environment. Related influences on food choices at work and at home were also examined. We recruited 28 low- and moderate-income, midlife (37-67 years) women from rural and urban areas of southeastern North Carolina, using typical case and snowball sampling. They responded to questions about multilevel influences on food choice in semi-structured, in-depth interviews. Women perceived differences between urban and rural food environments, with rural areas having fewer supermarkets and fast food restaurants compared to urban areas, which had fewer produce stands. Workplace food choices were affected by the social environment (co-workers), personal health concerns, and the surrounding food environment. Food chosen at home was primarily influenced by family members, health concerns, and convenient food sources. While future studies should explore findings in more representative populations, potential intervention strategies can be inferred, including emphasizing healthful aspects of the food environment. Intervention and advocacy efforts are needed to improve aspects of the food environment that make healthy choices difficult.
Primary care support for tackling obesity: a qualitative study of the perceptions of obese patients.
Brown, Ian; Thompson, Joanne; Tod, Angela; Jones, Georgina
2006-09-01
Obesity has become a major public health issue and there is concern about the response of health services to patients who are obese. The perceptions of obese patients using primary care services have not been studied in depth. To explore obese patients' experiences and perceptions of support in primary care. Qualitative study with semi-structured interviews conducted in participants' homes. Five general practices contrasting in socioeconomic populations in Sheffield. Purposive sampling and semi-structured interviewing of 28 patients with a diverse range of ages, backgrounds, levels of obesity and experiences of primary care services. Participants typically felt reluctance when presenting with concerns about weight and ambivalence about the services received. They also perceived there to be ambivalence and a lack of resources on the part of the health services. Participants showed a strong sense of personal responsibility about their condition and stigma-related cognitions were common. These contributed to their ambivalence about using services and their sensitivity to its features. Good relationships with primary care professionals and more intensive support partly ameliorated these effects. The challenges of improving access to and quality of primary care support in tackling obesity are made more complex by patients' ambivalence and other effects of the stigma associated with obesity.
Choi, Sandy Pin-Pin; Cheung, Kin; Pang, Samantha Mei-Che
2013-04-01
To examine how front-line registered nurses' perception of their work environment associates with and predicts nurse outcomes in terms of job satisfaction and turnover intention. Mounting evidence has pointed to an inseparable link between attributes of the nursing work environment and nurse outcomes. However, there is a paucity of research examining nurses' perception of their work environment beyond the Western context. This cross-sectional survey involved 1271 registered nurses working in 135 inpatient units in 10 public hospitals in Hong Kong. The instrument comprised items developed from in-depth interviews with front-line nurses that explored nurses' perception of their work environment. Factor analysis identified five dimensions (professionalism, co-worker relationship, management, staffing and resources, and ward practice) of the nursing work environment. Logistic regression analysis further identified professionalism, management and ward practice as significant factors in predicting nurses' turnover intention, and staffing and resources as an additional factor in predicting their job satisfaction. Attributes of the nursing work environment have a significant bearing on nurses' job satisfaction and intention to leave. Managerial effort should focus on improving nurses' work conditions through detailed resource planning, effective management and removal of work constraints that affect nursing practice. © 2012 Blackwell Publishing Ltd.
Preparing for practice: Nursing intern and faculty perceptions on clinical experiences.
AlThiga, Hanan; Mohidin, Sharifah; Park, Yoon Soo; Tekian, Ara
2017-04-01
Clinical experience and exposure to real patients are required elements of nursing education. Trainees in nursing are expected to be prepared adequately for the hard-working environment, increasing patient complexity, and higher-level competencies. This study investigates differences between nursing interns and clinical faculty on actual and perceived importance of educational preparation and development of clinical competencies, focusing on the nursing curriculum and transition to practice. A convenient sampling technique with a mixed-methods design was used to collect quantitative and qualitative data, by surveying and interviewing nursing interns and faculty members from King Abdul-Aziz University in Saudi Arabia; data collection occurred in December 2015. The survey (23 items) and focused interviews measured perceptions of clinical instruction and experience. Descriptive statistics and t-tests were used to analyze differences in mean ratings between actual and perceived importance. Themes collected from narrative interview data were summarized. Significant differences were found between nursing interns (n = 46) and faculty (n = 29) perceptions of actual clinical teaching and experiences and its importance including the clinical teaching and the development of clinical competence, p < .01. Moreover, nursing interns rated actual experiences of knowledge base and skills significantly lower than faculty perceptions, p = .001. Narrative data provided in-depth information on factors contributing and hindering the learning and teaching environment. Findings from this study call for clinical instruction and experiences to take a step further to meet current practice standards and to improve patient safety in the health professions education of nurses.
ERIC Educational Resources Information Center
Conole, Grainne; de Laat, Maarten; Dillon, Teresa; Darby, Jonathan
2008-01-01
The paper describes the findings from a study of students' use and experience of technologies. A series of in-depth case studies were carried out across four subject disciplines, with data collected via survey, audio logs and interviews. The findings suggest that students are immersed in a rich, technology-enhanced learning environment and that…
Oli, Natalia; Vaidya, Abhinav; Subedi, Madhusudan; Krettek, Alexandra
2014-01-01
Background Nepal currently faces an increasing burden of cardiovascular disease (CVD). Earlier studies on health literacy and the behavior dimension of cardiovascular health reported a substantial gap between knowledge and practice. Objective This qualitative study aimed to deepen understanding of the community perspective on cardiovascular health from the patients’ viewpoint. Design We conducted in-depth interviews (IDIs) with 13 individuals with confirmed heart disease, hypertension, or diabetes mellitus. All participants provided verbal consent. We used an IDI guide to ask respondents about their perception and experiences with CVD, particularly regarding causation and preventability. We manually applied qualitative content analysis to evaluate the data and grouped similar content into categories and subcategories. Results Respondents perceived dietary factors, particularly consumption of salty, fatty, and oily food, as the main determinants of CVD. Similarly, our respondents unanimously linked smoking, alcohol intake, and high blood pressure with cardiac ailments but reported mixed opinion regarding the causal role of body weight and physical inactivity. Although depressed and stressed at the time of diagnosis, respondents learned to handle their situation better over time. Despite good family support for health care, the financial burden of disease was a major issue. All respondents understood the importance of lifestyle modification and relied upon health professionals for information and motivation. Respondents remarked that community awareness of CVD was inadequate and that medical doctors or trained local people should help increase awareness. Conclusions This study provided insight into the perceptions of patients regarding CVD. Respondents embraced the importance of lifestyle modification only after receiving their diagnosis. Although better health care is important in terms of aiding patients to better understand and cope with their disease, interventions should be tailored to improve the community's cardiovascular health literacy and preventive practices. PMID:24802386
McCollum, Rosalind; Otiso, Lilian; Mireku, Maryline; Theobald, Sally; de Koning, Korrie; Hussein, Salim; Taegtmeyer, Miriam
2016-02-01
Global interest and investment in close-to-community health services is increasing. Kenya is currently revising its community health strategy (CHS) alongside political devolution, which will result in revisioning of responsibility for local services. This article aims to explore drivers of policy change from key informant perspectives and to study perceptions of current community health services from community and sub-county levels, including perceptions of what is and what is not working well. It highlights implications for managing policy change. We conducted 40 in-depth interviews and 10 focus group discussions with a range of participants to capture plural perspectives, including those who will influence or be influenced by CHS policy change in Kenya (policymakers, sub-county health management teams, facility managers, community health extension worker (CHEW), community health workers (CHWs), clients and community members) in two purposively selected counties: Nairobi and Kitui. Qualitative data were digitally recorded, transcribed, translated and coded before framework analysis. There is widespread community appreciation for the existing strategy. High attrition, lack of accountability for voluntary CHWs and lack of funds to pay CHW salaries, combined with high CHEW workload were seen as main drivers for strategy change. Areas for change identified include: lack of clear supervisory structure including provision of adequate travel resources, current uneven coverage and equity of community health services, limited community knowledge about the strategy revision and demand for home-based HIV testing and counselling. This in-depth analysis which captures multiple perspectives results in robust recommendations for strategy revision informed by the Five Wonders of Change Framework. These recommendations point towards a more people-centred health system for improved equity and effectiveness and indicate priority areas for action if success of policy change through the roll-out of the revised strategy is to be realized. © The Author 2015. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine.
Extremal edges: a powerful cue to depth perception and figure-ground organization.
Palmer, Stephen E; Ghose, Tandra
2008-01-01
Extremal edges (EEs) are projections of viewpoint-specific horizons of self-occlusion on smooth convex surfaces. An ecological analysis of viewpoint constraints suggests that an EE surface is likely to be closer to the observer than the non-EE surface on the other side of the edge. In two experiments, one using shading gradients and the other using texture gradients, we demonstrated that EEs operate as strong cues to relative depth perception and figure-ground organization. Image regions with an EE along the shared border were overwhelmingly perceived as closer than either flat or equally convex surfaces without an EE along that border. A further demonstration suggests that EEs are more powerful than classical figure-ground cues, including even the joint effects of small size, convexity, and surroundedness.
New Medicaid Enrollees In Oregon Report Health Care Successes And Challenges
Allen, Heidi; Wright, Bill J.; Baicker, Katherine
2014-01-01
Medicaid expansions will soon cover millions of new enrollees, but insurance alone may not ensure that they receive high-quality care. This study examines health care interactions and the health perceptions of an Oregon cohort three years after they gained Medicaid coverage. During in-depth qualitative interviews, 120 enrollees reported a wide range of interactions with the health care system. Forty percent of the new enrollees sought care infrequently because they were confused about coverage, faced access barriers, had bad interactions with providers, or felt that care was unnecessary. For the 60 percent who had multiple health care interactions, continuity and ease of the provider-patient relationship were critical to improved health. Some newly insured Medicaid enrollees recounted rapid improvements in health. However, most reported that gains came after months or years of working closely and systematically with a provider. Our findings suggest that improving communication with beneficiaries and increasing the availability of coordinated care across settings could reduce the barriers that new enrollees are likely to face. PMID:24493773
Mushi, D; Burton, K; Mtuya, C; Gona, J K; Walker, R; Newton, C R J C
2012-03-01
The effects of epilepsy on children and their families, factors influencing the treatment and education gap and socio-cultural beliefs about epilepsy in children in rural sub-Saharan Africa are not clearly defined. We conducted a qualitative study, with 38 in-depth interviews and 2 focus group discussions with carers of children with epilepsy (CWE) in Tanzania. Discrimination, isolation and lack of hope were identified as major issues. Poor school attendance was attributed to learning difficulties, behavior problems, ongoing seizures and restricted school access. The treatment gap was related to misdiagnosis, preferential use of traditional treatment and cost of biomedical treatment. The hopes expressed for the future centered on access to treatment and education. Improved access to diagnosis, cost-effective treatment, sensitization of the community on epilepsy, collaborative care provision with traditional and faith healers and improved access to specialist schooling could improve the quality of life and future of CWE in this region. Copyright © 2012 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Cameron, Mark; Taggar, Carolyn E.
2005-01-01
This qualitative study examined perceptions of the causes and nature of conflicts and violence among African-American girls in an urban high school. In-depth, iterative interviewing was used to explore the perceptions of these girls, male students, teachers, and other school personnel. Ethnographic observation was also used. Conflicts and violence…
ERIC Educational Resources Information Center
Lefevre, Pierre; de Suremain, Charles-Edouard; Rubin de Celis, Emma; Sejas, Edgar
2004-01-01
The paper discusses the utility of constructing causal models in focus groups. This was experienced as a complement to an in-depth ethnographic research on the differing perceptions of caretakers and health professionals on child's growth and development in Peru and Bolivia. The rational, advantages, difficulties and necessary adaptations of…
ERIC Educational Resources Information Center
Al-Awidi, Hamed Mubarak; Ismail, Sadiq Abdulwahed
2014-01-01
This study investigated ESL teachers' perceptions regarding the use of Computer Assisted Language Learning (CALL) in teaching reading to children. A random sample of 145 teachers participated in the study by completing a survey developed by the researchers. To explore the situation in depth, 16 teachers were later interviewed. Results indicated…
Farrington, Conor; Burt, Jenni; Boiko, Olga; Campbell, John; Roland, Martin
2017-06-01
Patient experience surveys are increasingly important in the measurement of, and attempts to improve, health-care quality. To date, little research has focused upon doctors' attitudes to surveys which give them personalized feedback. This paper explores doctors' perceptions of patient experience surveys in primary and secondary care settings in order to deepen understandings of how doctors view the plausibility of such surveys. We conducted a qualitative study with doctors in two regions of England, involving in-depth semi-structured interviews with doctors working in primary care (n = 21) and secondary care (n = 20) settings. The doctors in both settings had recently received individualized feedback from patient experience surveys. Doctors in both settings express strong personal commitments to incorporating patient feedback in quality improvement efforts. However, they also concurrently express strong negative views about the credibility of survey findings and patients' motivations and competence in providing feedback. Thus, individual doctors demonstrate contradictory views regarding the plausibility of patient surveys, leading to complex, varied and on balance negative engagements with patient feedback. Doctors' contradictory views towards patient experience surveys are likely to limit the impact of such surveys in quality improvement initiatives in primary and secondary care. We highlight the need for 'sensegiving' initiatives (i.e. attempts to influence perceptions by communicating particular ideas, narratives and visions) to engage with doctors regarding the plausibility of patient experience surveys. This study highlights the importance of engaging with doctors' views about patient experience surveys when developing quality improvement initiatives. © 2016 The Authors. Health Expectations Published by John Wiley & Sons Ltd.
[Conceptualizations on care for persons with dementia in nursing homes].
Rodríguez-Martín, Beatriz; Martínez-Andrés, María; Notario-Pacheco, Blanca; Martínez-Vizcaíno, Vicente
2016-03-01
Despite the importance of family perceptions when analyzing care for the elderly in nursing homes, little is said about this aspect. This study aims to identify preferences and areas for improvement in care for persons with dementia, as perceived by families. A qualitative study was performed, based on Grounded Theory, combining two data collection techniques (participant observation and in-depth interviews) in a theoretical sample of institutionalized persons with dementia. The ideal model of care for persons with dementia, as perceived by participants, was based on specialized and individualized care and family participation in the care provided. Areas for improvement included aspects pertaining to specialized training in geriatrics, human relations, and the culture of institutional work. Faced with the current trend towards technification of care, families are now demanding personalized, small-scale care in which they form an active part of the team.
... hands Fatigue Nausea Shortness of breath Blurred Vision Tinnitus Difficulty swallowing Leg weakness % 98 84 72 69 ... system) may not work properly, which may cause tinnitus (ringing in the ears), depth perception, running into ...
Turkmani, Sabera; Currie, Sheena; Mungia, Jaime; Assefi, Nassim; Javed Rahmanzai, Ahmed; Azfar, Pashtun; Bartlett, Linda
2013-10-01
over the last decade Afghanistan has made large investments in scaling up the number of midwives to address access to skilled care and the high burden of maternal and newborn mortality. at the request of the Ministry of Public Health (MOPH) an evaluation was undertaken to improve the pre-service midwifery education programme through identification of its strengths and weaknesses. The qualitative component of the evaluation specifically examined: (1) programme strengths; (2) programme weaknesses; (3) perceptions of the programme's community impact; (4) barriers to provision of care and challenges to impact; (5) perceptions of the recently graduated midwife's field experience, and (6) recommendations for programme improvement. the evaluation used a mixed methods approach that included qualitative and quantitative components. This paper focuses on the qualitative components which included in-depth interviews with 138 graduated midwives and 20 key informants as well as 24 focus group discussions with women. eight provinces in Afghanistan with functioning and accredited midwifery schools between June 2008 and November 2010. midwives graduated from one of the two national midwifery programmes: Institute of Health Sciences and Community Midwifery Education. Key informants comprised of stakeholders and female residents of the midwives catchment areas. midwives described overall satisfaction with the quality of their education. Midwives and stakeholders perceived that women were more likely to use maternal and child health services in communities where midwives had been deployed. Strengths included evidence-based content, standardised materials, clinical training, and supportive learning environment. Self-reported aspects of the quality education in respect to midwives empowerment included feeling competent and confident as demonstrated by respect shown by co-workers. Weaknesses of the programme included perceived low educational requirement to enter the programme and readiness of programmes to commence education. Insecurity and geographical remoteness are perceived as challenges with clients' access to care and the ability of midwives to make home visits. the depth of midwives' contribution in Afghanistan - from increased maternal health care service utilisation to changing community's perceptions of women's education and professional independence - is overwhelmingly positive. Lessons learned can serve as a model to other low resource, post-conflict settings that are striving to increase the workforce of skilled providers. © 2013 The Authors. Published by Elsevier Ltd. All rights reserved.
De Jesus, Maria; Taylor, Juanita; Maine, Cathleen; Nalls, Patricia
2015-01-01
Background To date, there are very few comparative US studies and none in DC that distinguish between US-born and foreign-born Black women to examine and compare their perceptions of HIV risk. This qualitative study, therefore, analyzes African American and East African women’s perceptions of HIV risk in the Washington DC Metropolitan area, which has the highest AIDS rate in the US. Methods Forty in-depth, semi-structured interviews and 10 cognitive interviews were conducted among a sample of 25 African American women and 25 East African born women between October 2012 and March 2013 to examine perceptions regarding HIV risk. The in-depth semi-structured interviews were preceded by the cognitive interviews and accompanying survey. Study protocol was reviewed and approved by the American University Institutional Review Board. Results Adopting Boerma and Weir’s Proximate Determinants conceptual framework to interpret the data, the results of the study demonstrate that African American and East African immigrant women have divergent perceptions of HIV risk. While African American women ascribe HIV risk to individual-level behaviors and choices such as unprotected sex, East African women attribute HIV risk to conditions of poverty and survival. Conclusions Study findings suggest that addressing HIV prevention and education among Black women in DC will require distinct and targeted strategies that are culturally and community-centered in order to resonate with these different audiences. PMID:26766523
De Jesus, Maria; Taylor, Juanita; Maine, Cathleen; Nalls, Patricia
2016-02-01
To date, there are very few comparative US studies and none in DC that distinguish between US-born and foreign-born black women to examine and compare their perceptions of HIV risk. This qualitative study, therefore, analyzes African American and East African women's perceptions of HIV risk in the Washington DC Metropolitan area, which has the highest AIDS rate in the United States. Forty in-depth, semistructured interviews and 10 cognitive interviews were conducted among a sample of 25 African American women and 25 East African born women between October 2012 and March 2013 to examine perceptions regarding HIV risk. The in-depth semistructured interviews were preceded by the cognitive interviews and accompanying survey. Study protocol was reviewed and approved by the American University Institutional Review Board. Adopting Boerma and Weir's Proximate Determinants conceptual framework to interpret the data, the results of the study demonstrate that African American and East African immigrant women have divergent perceptions of HIV risk. Although African American women ascribe HIV risk to individual-level behaviors and choices such as unprotected sex, East African women attribute HIV risk to conditions of poverty and survival. Study findings suggest that addressing HIV prevention and education among black women in DC will require distinct and targeted strategies that are culturally and community-centered to resonate with these different audiences.
Cedraschi, Christine; Delézay, Sylvie; Marty, Marc; Berenbaum, Francis; Bouhassira, Didier; Henrotin, Yves; Laroche, Françoise; Perrot, Serge
2013-01-01
Introduction Pain is the primary outcome measurement in osteoarthritis, and its assessment is mostly based on its intensity. The management of this difficult chronic condition could be improved by using pain descriptors to improve analyses of painful sensations. This should help to define subgroups of patients based on pain phenotype, for more adapted treatment. This study draws upon patients’ descriptions of their pain, to identify and understand their perception of osteoarthritis pain and to categorize pain dimensions. Methods This qualitative study was conducted with representative types of patients suffering from osteoarthritis. Two focus groups were conducted with a sample of 14 participants, with either recent or chronic OA, at one or multiple sites. Focus groups were semi-structured and used open-ended questions addressing personal experiences to explore the experiences of patients with OA pain and the meanings they attributed to these pains. Results Two main points emerged from content analyses: -A major difficulty in getting patients to describe their osteoarthritis pain: perception that nobody wants to hear about it; necessity to preserve one’s self and social image; notion of self-imposed stoicism; and perception of osteoarthritis as a complex, changing, illogical disease associated with aging. -Osteoarthritis pains were numerous and differed in intensity, duration, depth, type of occurrence, impact and rhythm, but also in painful sensations and associated symptoms. Based on analyses of the verbatim interviews, seven dimensions of OA pain emerged: pain sensory description, OA-related symptoms, pain variability profile, pain-triggering factors, pain and physical activity, mood and image, general physical symptoms. Summary In osteoarthritis, pain analysis should not be restricted to intensity. Our qualitative study identified pain descriptors and defined seven dimensions of osteoarthritis pain. Based on these dimensions, we aim to develop a specific questionnaire on osteoarthritis pain quality for osteoarthritis pain phenotyping: the OsteoArthritis Symptom Inventory Scale (OASIS). PMID:24244589
Capezuti, Elizabeth; Boltz, Marie; Cline, Daniel; Dickson, Victoria Vaughn; Rosenberg, Marie-Claire; Wagner, Laura; Shuluk, Joseph; Nigolian, Cindy
2012-01-01
Aims and objectives To explain the relationship between a positive nurse practice environment (NPE) and implementation of evidence-based practices. To describe the components of NICHE (Nurses Improving Care for Healthsystem Elders) programmes that contribute to a positive geriatric nursing practice environment. Background The NPE is a system-level intervention for promoting quality and patient safety; however, there are population-specific factors that influence the nurses’ perception of their practice and its’ relationship with patient outcomes. Favourable perceptions of the geriatric-specific NPE are associated with better perceptions of geriatric care quality. Designs Discursive paper. Method In this selective critical analysis of the descriptive and empirical literature, we present the implementation of geriatric models in relation to the NPE and components of the NICHE programme that support hospitals’ systemic capacity to effectively integrate and sustain evidence-based geriatric knowledge into practice. Results Although there are several geriatric models and chronic care models available, NICHE has been the most successful in recruiting hospital membership as well as contributing to the depth of geriatric hospital programming. Conclusions Although all geriatric care models require significant nursing input, only NICHE focuses on the nursing staff’s perception of the care environment for geriatric practice. Studies in NICHE hospitals demonstrate that quality geriatric care requires a NPE in which the structure and processes of hospital services focus on specific patient care needs. Relevance to clinical practice The implementation of evidence-based models addressing the unique needs of hospitalised older adults requires programmes such as NICHE that serve as technical resources centre and a catalyst for networking among facilities committed to quality geriatric care. Unprecedented international growth in the ageing population compels us to examine how to adapt the successful components of NICHE to the distinctive needs of health systems throughout the world that serve older adults. PMID:23083387
Torri, Maria Costanza
2013-07-01
Despite the fact that plants have played an important role in midwifery in many cultures, there are very few in-depth studies on the plants traditionally used by midwives. The aim of this study is to analyse the perceptions and the uses of medicinal plants for reproductive health among indigenous midwives in the city of Otavalo, Ecuador. The article also aims to analyse the perceptions of traditional midwives regarding allopathic drugs for reproductive health and their possible overlapping uses of medicinal plants and allopathic drugs. The data are drawn from an ethnographic study carried out in Ecuador. In total, 20 traditional midwives have been interviewed. Individual and in-depth interviews also took place with a sample of 35 women as well as with five nurses and two doctors working at San Luis Hospital in Otavalo. The study shows that cultural health management and the incorporation of the beliefs and practices relating to women's reproductive health can represent a starting point towards the search for more successful strategies in reproductive health. Copyright © 2012 Elsevier Ltd. All rights reserved.
Miiro, George; DeCelles, Jeff; Rutakumwa, Rwamahe; Nakiyingi-Miiro, Jessica; Muzira, Philip; Ssembajjwe, Wilber; Musoke, Saidat; Gibson, Lorna J; Hershow, Rebecca B; Francis, Suzanna; Torondel, Belen; Ross, David A; Weiss, Helen A
2017-01-01
The Ugandan government is committed to scaling-up proven HIV prevention strategies including safe male circumcision, and innovative strategies are needed to increase circumcision uptake. The aim of this study was to assess the acceptability and feasibility of implementing a soccer-based intervention ("Make The Cut") among schoolboys in a peri-urban district of Uganda. The intervention was led by trained, recently circumcised "coaches" who facilitated a 60-minute session delivered in schools, including an interactive penalty shoot-out game using metaphors for HIV prevention, sharing of the coaches' circumcision story, group discussion and ongoing engagement from the coach to facilitate linkage to male circumcision. The study took place in four secondary schools in Entebbe sub-district, Uganda. Acceptability of safe male circumcision was assessed through a cross-sectional quantitative survey. The feasibility of implementing the intervention was assessed by piloting the intervention in one school, modifying it, and implementing the modified version in a second school. Perceptions of the intervention were assessed with in-depth interviews with participants. Of the 210 boys in the cross-sectional survey, 59% reported being circumcised. Findings showed high levels of knowledge and generally favourable perceptions of circumcision. The initial implementation of Make The Cut resulted in 6/58 uncircumcised boys (10.3%) becoming circumcised. Changes made included increasing engagement with parents and improved liaison with schools regarding the timing of the intervention. Following this, uptake improved to 18/69 (26.1%) in the second school. In-depth interviews highlighted the important role of family and peer support and the coach in facilitating the decision to circumcise. This study showed that the modified Make The Cut intervention may be effective to increase uptake of safe male circumcision in this population. However, the intervention is time-intensive, and further work is needed to assess the cost-effectiveness of the intervention conducted at scale.
Assessing the Consequences of Stigma for Tuberculosis Patients in Urban Zambia
Cremers, Anne Lia; de Laat, Myrthe Manon; Kapata, Nathan; Gerrets, Rene; Klipstein-Grobusch, Kerstin; Grobusch, Martin Peter
2015-01-01
Background Stigma is one of the many factors hindering tuberculosis (TB) control by negatively affecting hospital delay and treatment compliance. In Zambia, the morbidity and mortality due to TB remains high, despite extended public health attempts to control the epidemic and to diminish stigma. Study Aim To enhance understanding of TB-related stigmatizing perceptions and to describe TB patients’ experiences of stigma in order to point out recommendations to improve TB policy. Methods We conducted a mixed method study at Kanyama clinic and surrounding areas, in Lusaka, Zambia; structured interviews with 300 TB patients, multiple in-depth interviews with 30 TB patients and 10 biomedical health workers, 3 focus group discussions with TB patients and treatment supporters, complemented by participant observation and policy analysis of the TB control program. Predictors of stigma were identified by use of multivariate regression analyses; qualitative analysis of the in-depth interviews, focus group discussions and participant observation was used for triangulation of the study findings. Results We focused on the 138/300 patients that described TB-related perceptions and attitudes, of whom 113 (82%) reported stigma. Stigma provoking TB conceptions were associated with human immunodeficiency virus (HIV)-infection, alleged immoral behaviour, (perceived) incurability, and (traditional) myths about TB aetiology. Consequences of stigma prevailed both among children and adults and included low self-esteem, insults, ridicule, discrimination, social exclusion, and isolation leading to a decreased quality of life and social status, non-disclosure, and/or difficulties with treatment compliance and adherence. Women had significantly more stigma-related problems than men. Conclusions The findings illustrate that many TB patients faced stigma-related issues, often hindering effective TB control and suggesting that current efforts to reduce stigma are not yet optimal. The content and implementation of sensitization programs should be improved and more emphasis needs to be placed on women and children. PMID:25806955
DeCelles, Jeff; Rutakumwa, Rwamahe; Nakiyingi-Miiro, Jessica; Muzira, Philip; Ssembajjwe, Wilber; Musoke, Saidat; Gibson, Lorna J.; Hershow, Rebecca B.; Francis, Suzanna; Torondel, Belen; Ross, David A.
2017-01-01
The Ugandan government is committed to scaling-up proven HIV prevention strategies including safe male circumcision, and innovative strategies are needed to increase circumcision uptake. The aim of this study was to assess the acceptability and feasibility of implementing a soccer-based intervention (“Make The Cut”) among schoolboys in a peri-urban district of Uganda. The intervention was led by trained, recently circumcised “coaches” who facilitated a 60-minute session delivered in schools, including an interactive penalty shoot-out game using metaphors for HIV prevention, sharing of the coaches’ circumcision story, group discussion and ongoing engagement from the coach to facilitate linkage to male circumcision. The study took place in four secondary schools in Entebbe sub-district, Uganda. Acceptability of safe male circumcision was assessed through a cross-sectional quantitative survey. The feasibility of implementing the intervention was assessed by piloting the intervention in one school, modifying it, and implementing the modified version in a second school. Perceptions of the intervention were assessed with in-depth interviews with participants. Of the 210 boys in the cross-sectional survey, 59% reported being circumcised. Findings showed high levels of knowledge and generally favourable perceptions of circumcision. The initial implementation of Make The Cut resulted in 6/58 uncircumcised boys (10.3%) becoming circumcised. Changes made included increasing engagement with parents and improved liaison with schools regarding the timing of the intervention. Following this, uptake improved to 18/69 (26.1%) in the second school. In-depth interviews highlighted the important role of family and peer support and the coach in facilitating the decision to circumcise. This study showed that the modified Make The Cut intervention may be effective to increase uptake of safe male circumcision in this population. However, the intervention is time-intensive, and further work is needed to assess the cost-effectiveness of the intervention conducted at scale. PMID:29016651
Psychophysical Studies of Visual Cortical Function
1992-01-12
principle of generic image samplin& a hypothesis which provides ageometric tool to understand visual surface learning. We also have investigated the...perception of depth from unpaired points ( DaVinci stereopsis), showing that such points lead to depth andsubjective contours. In color filling in, we have...outlined and systematized a number of important phenomenon which we label under the rubric of DaVinci stereopsis. We summarize these results in a number of
NASA Technical Reports Server (NTRS)
Kaiser, Mary K.; Proffitt, Dennis R.
1992-01-01
Recent developments in microelectronics have encouraged the use of 3D data bases to create compelling volumetric renderings of graphical objects. However, even with the computational capabilities of current-generation graphical systems, real-time displays of such objects are difficult, particularly when dynamic spatial transformations are involved. In this paper we discuss a type of visual stimulus (the stereokinetic effect display) that is computationally far less complex than a true three-dimensional transformation but yields an equally compelling depth impression, often perceptually indiscriminable from the true spatial transformation. Several possible applications for this technique are discussed (e.g., animating contour maps and air traffic control displays so as to evoke accurate depth percepts).
NASA Astrophysics Data System (ADS)
Bostaph, Ekaterina
This research aimed to study the potential for breaking through object size limitations of current X-ray computed tomography (CT) systems by implementing a limited angle scanning technique. CT stands out among other industrial nondestructive inspection (NDI) methods due to its unique ability to perform 3D volumetric inspection, unmatched micro-focus resolution, and objectivity that allows for automated result interpretation. This work attempts to advance NDI technique to enable microstructural material characterization and structural diagnostics of composite structures, where object sizes often prohibit the application of full 360° CT. Even in situations where the objects can be accommodated within existing micro-CT configuration, achieving sufficient magnification along with full rotation may not be viable. An effort was therefore made to achieve high-resolution scans from projection datasets with limited angular coverage (less than 180°) by developing effective reconstruction algorithms in conjunction with robust scan acquisition procedures. Internal features of inspected objects barely distinguishable in a 2D X-ray radiograph can be enhanced by additional projections that are reconstructed to a stack of slices, dramatically improving depth perception, a technique referred to as digital tomosynthesis. Building on the success of state-of-the-art medical tomosynthesis systems, this work sought to explore the feasibility of this technique for composite structures in aerospace applications. The challenge lies in the fact that the slices generated in medical tomosynthesis are too thick for relevant industrial applications. In order to adapt this concept to composite structures, reconstruction algorithms were expanded by implementation of optimized iterative stochastic methods (capable of reducing noise and refining scan quality) which resulted in better depth perception. The optimal scan acquisition procedure paired with the improved reconstruction algorithm facilitated higher in-plane and depth resolution compared to the clinical application. The developed limited angle tomography technique was demonstrated to be able to detect practically significant manufacturing defects (voids) and structural damage (delaminations) critical to structural integrity of composite parts. Keeping in mind the intended real-world aerospace applications where objects often have virtually unlimited in-plane dimensions, the developed technique of partial scanning could potentially extend the versatility of CT-based inspection and enable game changing NDI systems.
[Hospital self-management policy in Chile: perceptions of decision-makers].
Méndez, Claudio A; Miranda, Christian; Torres, M Cristina; Márquez, Myriam
2013-01-01
To learn the perceptions of decision-makers concerning the imple-men-t-ation stage of a hospital self-management policy in two highly complex hospitals in southern Chile. A descriptive, exploratory, qualitative study based on semi-structured in-depth interviews of decision-makers at the Regional Hospital of Valdivia and the Hospital San José de Osorno from August 2010 to December 2011. A convenience sample of 26 decision-makers was selected. The 26 interviews were recorded and transcribed verbatim. The information was analyzed using inductive content analysis. The interviewees consider the concept of self-management to be determined by autonomy in decision-making about resource allocation and the financing of health service delivery in the hospitals. They also stated that human resources and financing policies should be included to improve the implementation stage. They related weaknesses with the lack of organizational capabilities and managerial skills in the health teams implementing the changes. Conceptually, the hospital self-management policy is based on financial autonomy, and implementation is affected by persistent capacity gaps in policy design.
Wong, Eliza M L; Zhong, Xue Bing; Sit, Janet W H; Chair, Sek Ying; Leung, Doris Y P; Leung, Carmen; Leung, K C
2016-09-01
This study examined the attitudes of Chinese patients with coronary heart disease (CHD) toward the outpatient cardiac rehabilitation program (OCRP), as well as their exercise behavior, intention, maintenance and related factors. A qualitative descriptive study design was used, and 22 CHD patients were recruited in Hong Kong in 2014. In-depth interviews and content analyses were conducted. The tripartite model of attitudes was adopted as research framework. Two themes were identified: (1) informant attitude (perception, affection, and practice) toward the OCRP and (2) Exercise Behavior - intention, maintenance and its related factors. Most informants showed positive perception and affection regarding the outpatient rehabilitation program, leading to regular practice of exercise in the program and at home. Peer, group dynamic, social support and Chinese culture influences on exercise behavior may serve as major facilitators to maintain exercise behavior. Positive attitude toward the OCRP enhanced the participation rate, whereas peer and social support from the family and workplace were useful to improve the maintenance of exercise behavior. Overall, this study provides insights into strategic planning for the OCRP and continual support for CHD patients in the community.
Servin, Argentina E; Muñoz, Fátima A; Zúñiga, María Luisa
2014-01-01
Latinos living with HIV residing in the US-Mexico border region frequently seek care on both sides of the border. Given this fact, a border health perspective to understanding barriers to care is imperative to improve patient health outcomes. This qualitative study describes and compares experiences and perceptions of Mexican and US HIV care providers regarding barriers to HIV care access for Latino patients living in the US-Mexico border region. In 2010, we conducted in-depth qualitative interviews with HIV care providers in Tijuana (n = 10) and San Diego (n = 9). We identified important similarities and differences between Mexican and US healthcare provider perspectives on HIV care access and barriers to service utilisation. Similarities included the fact that HIV-positive Latino patients struggle with access to ART medication, mental health illness, substance abuse and HIV-related stigma. Differences included Mexican provider perceptions of medication shortages and US providers feeling that insurance gaps influenced medication access. Differences and similarities have important implications for cross-border efforts to coordinate health services for patients who seek care in both countries.
Villa-Torres, Laura; Fleming, Paul; Barrington, Clare
2016-01-01
The promotor de salud, or community health worker (CHW) role, is highly feminized and little is known about how men view their participation in CHW programs. We conducted in-depth interviews with Latino men in North Carolina to explore this gap. We used systematic coding and display procedures informed by Grounded Theory to analyze the data. Men described their communities as lacking cohesion, making integration of Latino immigrants difficult. Most did not consider themselves leaders or feel they had leaders in their communities. Their perceptions of the feminized CHW role as well as the volunteer or low-paid nature of CHW work conflicted with men’s provider role. They also did not think they could perform the CHW role because they lacked education, skills, and broad networks. Efforts to increase male participation in CHW programs in new Latino immigrant destinations will need to understand and address these gender and migration-related dynamics in order to engage both women and men in improving the health of their communities. PMID:24989349
Mothers' perceptions of children's food behaviors: use of focus group interview study
Lee, Young-Mee; Oh, Yu-Jin; Lee, Min-June
2008-01-01
Children's food behaviors have been expressed in a various ways because of recent changes in their family environment. Thus, this study was performed to investigate in-depth qualitative research on the mother's perception on children's food behaviors by focused group interview. This study was designed in four steps of planning, collection of participants, process, and analysis. Participants for the focus group interview were recruited and sampled from households with elementary school students in the Seoul and Gyeonggido areas. Groups were divided by total income and education expense levels. 1) High income household: It is better to improve currently existing web sites for nutrition education. 2) Mid income household: Easy, practical, and inexpensive off-line cooking class/nutrition education classes for mothers are needed. Nutrition programs for children should be developed through mass media and be promoted in the broadcasting circle. 3) Low income household: Motivation is required for mothers' education and the serious nutritional problems of children should be informed through mass media and home correspondence from school. And interesting educational materials should be developed for children to read whenever they want. PMID:20016728
Li, Zhi; Sun, Emily; Strawser, Cassandra J.; Spiegel, Ariana; Klein, Brennan; Durgin, Frank H.
2012-01-01
Two experiments are reported concerning the perception of ground extent in order to discover whether prior reports of anisotropy between frontal extents and extents in depth were consistent across different measures (visual matching and pantomime walking) and test environments (outdoor environments and virtual environments). In Experiment 1 it was found that depth extents of up to 7 m are indeed perceptually compressed relative to frontal extents in an outdoor environment, and that perceptual matching provided more precise estimates than did pantomime walking. In Experiment 2, similar anisotropies were found using similar tasks in a similar (but virtual) environment. In both experiments pantomime walking measures seemed to additionally compress the range of responses. Experiment 3 supported the hypothesis that range compression in walking measures of perceived distance might be due to proactive interference (memory contamination). It is concluded that walking measures are calibrated for perceived egocentric distance, but that pantomime walking measures may suffer range compression. Depth extents along the ground are perceptually compressed relative to frontal ground extents in a manner consistent with the angular scale expansion hypothesis. PMID:22889186
Verstraten, Frans A J; Niehorster, Diederick C; van de Grind, Wim A; Wade, Nicholas J
2015-10-01
In his original contribution, Exner's principal concern was a comparison between the properties of different aftereffects, and particularly to determine whether aftereffects of motion were similar to those of color and whether they could be encompassed within a unified physiological framework. Despite the fact that he was unable to answer his main question, there are some excellent-so far unknown-contributions in Exner's paper. For example, he describes observations that can be related to binocular interaction, not only in motion aftereffects but also in rivalry. To the best of our knowledge, Exner provides the first description of binocular rivalry induced by differently moving patterns in each eye, for motion as well as for their aftereffects. Moreover, apart from several known, but beautifully addressed, phenomena he makes a clear distinction between motion in depth based on stimulus properties and motion in depth based on the interpretation of motion. That is, the experience of movement, as distinct from the perception of movement. The experience, unlike the perception, did not result in a motion aftereffect in depth.
Niehorster, Diederick C.; van de Grind, Wim A.; Wade, Nicholas J.
2015-01-01
In his original contribution, Exner’s principal concern was a comparison between the properties of different aftereffects, and particularly to determine whether aftereffects of motion were similar to those of color and whether they could be encompassed within a unified physiological framework. Despite the fact that he was unable to answer his main question, there are some excellent—so far unknown—contributions in Exner’s paper. For example, he describes observations that can be related to binocular interaction, not only in motion aftereffects but also in rivalry. To the best of our knowledge, Exner provides the first description of binocular rivalry induced by differently moving patterns in each eye, for motion as well as for their aftereffects. Moreover, apart from several known, but beautifully addressed, phenomena he makes a clear distinction between motion in depth based on stimulus properties and motion in depth based on the interpretation of motion. That is, the experience of movement, as distinct from the perception of movement. The experience, unlike the perception, did not result in a motion aftereffect in depth. PMID:27648213
The Limits of Human Stereopsis in Space and Time
Kane, David; Guan, Phillip
2014-01-01
To encode binocular disparity, the visual system determines the image patches in one eye that yield the highest correlation with patches in the other eye. The computation of interocular correlation occurs after spatiotemporal filtering of monocular signals, which leads to restrictions on disparity variations that can support depth perception. We quantified those restrictions by measuring humans' ability to see disparity variation at a wide range of spatial and temporal frequencies. Lower-disparity thresholds cut off at very low spatiotemporal frequencies, which is consistent with the behavior of V1 neurons. Those thresholds are space–time separable, suggesting that the underlying neural mechanisms are separable. We also found that upper-disparity limits were characterized by a spatiotemporal, disparity-gradient limit; to be visible, disparity variation cannot exceed a fixed amount for a given interval in space–time. Our results illustrate that the disparity variations that humans can see are very restricted compared with the corresponding luminance variations. The results also provide insight into the neural mechanisms underlying depth from disparity, such as why stimuli with long interocular delays can still yield clear depth percepts. PMID:24453329
Bouquet de Joliniere, Jean; Librino, Armando; Dubuisson, Jean-Bernard; Khomsi, Fathi; Ben Ali, Nordine; Fadhlaoui, Anis; Ayoubi, J. M.; Feki, Anis
2016-01-01
Minimally invasive surgery (MIS) can be considered as the greatest surgical innovation over the past 30 years. It revolutionized surgical practice with well-proven advantages over traditional open surgery: reduced surgical trauma and incision-related complications, such as surgical-site infections, postoperative pain and hernia, reduced hospital stay, and improved cosmetic outcome. Nonetheless, proficiency in MIS can be technically challenging as conventional laparoscopy is associated with several limitations as the two-dimensional (2D) monitor reduction in-depth perception, camera instability, limited range of motion, and steep learning curves. The surgeon has a low force feedback, which allows simple gestures, respect for tissues, and more effective treatment of complications. Since the 1980s, several computer sciences and robotics projects have been set up to overcome the difficulties encountered with conventional laparoscopy, to augment the surgeon’s skills, achieve accuracy and high precision during complex surgery, and facilitate widespread of MIS. Surgical instruments are guided by haptic interfaces that replicate and filter hand movements. Robotically assisted technology offers advantages that include improved three-dimensional stereoscopic vision, wristed instruments that improve dexterity, and tremor canceling software that improves surgical precision. PMID:27200358
Oncology nurses and the experience of participation in an evidence-based practice project.
Fridman, Mary; Frederickson, Keville
2014-07-01
To illuminate the experiences of oncology nurses who participated in an evidence-based practice (EBP) project in an institution with an EBP organizational structure. A descriptive phenomenologic approach and in-depth interviews with each participant. An oncology-focused academic medical center with an established organizational infrastructure for EBP. 12 RNs working in an oncology setting who participated in an EBP project. Descriptive, qualitative phenomenologic approach through use of interviews and analysis of interview text. Four essential themes (i.e., support, challenges, evolution, and empowerment) and 11 subthemes emerged that reflected nurses' professional and personal growth, as well as the creation of a culture of EBP in the workplace. The participants described the EBP project as a positive, empowering personal and professional evolutionary experience with supports and challenges that resulted in improvements in patient care. To the authors' knowledge, the current study is the first qualitative study to demonstrate improved nursing outcomes (e.g., professional growth, improved nursing performance) and nurses' perception of improved patient outcomes (e.g., ongoing healthcare collaboration, evidence-based changes in practice).
Bornhoft, J M; Strabala, K W; Wortman, T D; Lehman, A C; Oleynikov, D; Farritor, S M
2011-01-01
The objective of this research is to study the effectiveness of using a stereoscopic visualization system for performing remote surgery. The use of stereoscopic vision has become common with the advent of the da Vinci® system (Intuitive, Sunnyvale CA). This system creates a virtual environment that consists of a 3-D display for visual feedback and haptic tactile feedback, together providing an intuitive environment for remote surgical applications. This study will use simple in vivo robotic surgical devices and compare the performance of surgeons using the stereoscopic interfacing system to the performance of surgeons using one dimensional monitors. The stereoscopic viewing system consists of two cameras, two monitors, and four mirrors. The cameras are mounted to a multi-functional miniature in vivo robot; and mimic the depth perception of the actual human eyes. This is done by placing the cameras at a calculated angle and distance apart. Live video streams from the left and right cameras are displayed on the left and right monitors, respectively. A system of angled mirrors allows the left and right eyes to see the video stream from the left and right monitor, respectively, creating the illusion of depth. The haptic interface consists of two PHANTOM Omni® (SensAble, Woburn Ma) controllers. These controllers measure the position and orientation of a pen-like end effector with three degrees of freedom. As the surgeon uses this interface, they see a 3-D image and feel force feedback for collision and workspace limits. The stereoscopic viewing system has been used in several surgical training tests and shows a potential improvement in depth perception and 3-D vision. The haptic system accurately gives force feedback that aids in surgery. Both have been used in non-survival animal surgeries, and have successfully been used in suturing and gallbladder removal. Bench top experiments using the interfacing system have also been conducted. A group of participants completed two different surgical training tasks using both a two dimensional visual system and the stereoscopic visual system. Results suggest that the stereoscopic visual system decreased the amount of time taken to complete the tasks. All participants also reported that the stereoscopic system was easier to utilize than the two dimensional system. Haptic controllers combined with stereoscopic vision provides for a more intuitive virtual environment. This system provides the surgeon with 3-D vision, depth perception, and the ability to receive feedback through forces applied in the haptic controller while performing surgery. These capabilities potentially enable the performance of more complex surgeries with a higher level of precision.
Fibromyalgia Pain: Options for Coping
... 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 ...
... J, et al. A national survey on public perceptions of miscarriage. Obstetrics & Gynecology. 2015;125:1313. Kropmans ... conditions/pregnancy-loss-miscarriage/in-depth/pregnancy-loss/art-20047983 . Mayo Clinic Footer Legal Conditions and Terms ...
Dynamic lens and monovision 3D displays to improve viewer comfort.
Johnson, Paul V; Parnell, Jared Aq; Kim, Joohwan; Saunter, Christopher D; Love, Gordon D; Banks, Martin S
2016-05-30
Stereoscopic 3D (S3D) displays provide an additional sense of depth compared to non-stereoscopic displays by sending slightly different images to the two eyes. But conventional S3D displays do not reproduce all natural depth cues. In particular, focus cues are incorrect causing mismatches between accommodation and vergence: The eyes must accommodate to the display screen to create sharp retinal images even when binocular disparity drives the eyes to converge to other distances. This mismatch causes visual discomfort and reduces visual performance. We propose and assess two new techniques that are designed to reduce the vergence-accommodation conflict and thereby decrease discomfort and increase visual performance. These techniques are much simpler to implement than previous conflict-reducing techniques. The first proposed technique uses variable-focus lenses between the display and the viewer's eyes. The power of the lenses is yoked to the expected vergence distance thereby reducing the mismatch between vergence and accommodation. The second proposed technique uses a fixed lens in front of one eye and relies on the binocularly fused percept being determined by one eye and then the other, depending on simulated distance. We conducted performance tests and discomfort assessments with both techniques and compared the results to those of a conventional S3D display. The first proposed technique, but not the second, yielded clear improvements in performance and reductions in discomfort. This dynamic-lens technique therefore offers an easily implemented technique for reducing the vergence-accommodation conflict and thereby improving viewer experience.
Hogle, Nancy J; Widmann, Warren D; Ude, Aku O; Hardy, Mark A; Fowler, Dennis L
2008-01-01
To determine whether LapSim training (version 3.0; Surgical Science Ltd, Göteborg, Sweden) to criteria for novice PGY1 surgical residents had predictive validity for improvement in the performance of laparoscopic cholecystectomy. In all, 21 PGY1 residents performed laparoscopic cholecystectomies in pigs after minimal training; their performance was evaluated by skilled laparoscopic surgeons using the validated tool GOALS (global operative assessment of laparoscopic operative skills: depth perception, bimanual dexterity, efficiency, tissue handling, and overall competence). From the group, 10 residents trained to competency on the LapSim Basic Skills Programs (camera navigation, instrument navigation, coordination, grasping, lifting and grasping, cutting, and clip applying). All 21 PGY1 residents again performed laparoscopic cholecystectomies on pigs; their performance was again evaluated by skilled laparoscopic surgeons using GOALS. Additionally, we studied the rate of learning to determine whether the slow or fast learners on the LapSim performed equivalently when performing actual cholecystectomies in pigs. Finally, 6 categorical residents were tracked, and their clinical performance on all of the laparoscopic cholecystectomies in which they were "surgeon, junior" was prospectively evaluated using the GOALS criteria. We found a statistical improvement of depth perception in the operative performance of cholecystectomies in pigs in the group trained on the LapSim. In the other 4 domains, a trend toward improvement was observed. No correlation between being a fast learner and the ultimate skill was demonstrated in the clinical performance of laparoscopic cholecystectomies. We did find that the fast learners on LapSim all were past or current video game players ("gamers"); however, that background did not translate into better clinical performance. Using current criteria, we doubt that the time and effort spent training novice PGY1 Surgical Residents on the basic LapSim training programs is justified, as such training to competence lacks predictive validity in most domains of the GOALS program. We are investigating 2 other approaches: more difficult training exercises using the LapSim system and an entirely different approach using haptic technology (ProMis; Haptica Ltd., Ireland), which uses real instruments, with training on realistic 3-dimensional models with real rather than simulated cutting, sewing, and dissection. Although experienced video gamers achieve competency faster than nongamers on LapSim programs, that skill set does not translate into improved clinical performance.
Okuga, Monica; Nabirye, Rose Chalo; Sewankambo, Nelson Kaulukusi; Nakanjako, Damalie
2017-01-01
Limited data are available on the experiences of parental HIV disclosure to children in Uganda. We conducted a qualitative study comprising sixteen in-depth interviews and four focus group discussions with parents receiving highly active antiretroviral therapy. Analysis was done using Atlas.ti qualitative research software. Back-and-forth triangulation was done between transcripts of the in-depth interviews and focus group discussions, and themes and subthemes were developed. Barriers to parents' disclosure included perceptions that children are too young to understand what HIV infection means and fears of secondary disclosure by the children. Immediate outcomes of disclosure included children getting scared and crying, although such instances often gave way to more enduring positive experiences for the parents, such as support in adherence to medical care, help in household chores, and a decrease in financial demands from the children. Country-specific interventions are needed to improve the process of parental HIV disclosure to children and this should encompass preparation on how to deal with the immediate psychological challenges associated with the parent's disclosure. PMID:29209538
Understanding Your Vision: The "Imperfect Eye"
... including peripheral awareness (side vision), eye coordination, depth perception, focusing ability, and color vision that make up ... the conditions for which you may be at risk." — Dr. Emily Chew National Eye Institute Farsighted If ...
Schouten, Ben; Troje, Nikolaus F.; Vroomen, Jean; Verfaillie, Karl
2011-01-01
Background The focus in the research on biological motion perception traditionally has been restricted to the visual modality. Recent neurophysiological and behavioural evidence, however, supports the idea that actions are not represented merely visually but rather audiovisually. The goal of the present study was to test whether the perceived in-depth orientation of depth-ambiguous point-light walkers (plws) is affected by the presentation of looming or receding sounds synchronized with the footsteps. Methodology/Principal Findings In Experiment 1 orthographic frontal/back projections of plws were presented either without sound or with sounds of which the intensity level was rising (looming), falling (receding) or stationary. Despite instructions to ignore the sounds and to only report the visually perceived in-depth orientation, plws accompanied with looming sounds were more often judged to be facing the viewer whereas plws paired with receding sounds were more often judged to be facing away from the viewer. To test whether the effects observed in Experiment 1 act at a perceptual level rather than at the decisional level, in Experiment 2 observers perceptually compared orthographic plws without sound or paired with either looming or receding sounds to plws without sound but with perspective cues making them objectively either facing towards or facing away from the viewer. Judging whether either an orthographic plw or a plw with looming (receding) perspective cues is visually most looming becomes harder (easier) when the orthographic plw is paired with looming sounds. Conclusions/Significance The present results suggest that looming and receding sounds alter the judgements of the in-depth orientation of depth-ambiguous point-light walkers. While looming sounds are demonstrated to act at a perceptual level and make plws look more looming, it remains a challenge for future research to clarify at what level in the processing hierarchy receding sounds affect how observers judge the in-depth perception of plws. PMID:21373181
Lam, Phoebe; Lopez Filici, Ana; Middleton, Claire; McGillicuddy, Patricia
2018-01-01
To practice interprofessional collaboration (IPC), understanding the roles of each profession in the team is key. Anesthesia assistants (AAs) are a relatively new addition to the Canadian healthcare system. As a result, its role in the delivery of anesthesia care can be misunderstood by other healthcare professionals. Using an exploratory multiple case study design, this article explores healthcare professionals' perceptions of the AA role and its impact on patients and IPC. Sixteen semi-structured, in-depth interviews were conducted with a purposive sample of nine healthcare professions from inside and outside the peri-operative care unit in two urban, acute care, university-affiliated teaching research hospitals in Ontario. A thematic analysis of the interview transcripts identified five overarching themes: limited understanding of the AA role, improved patient-centred care, improve IPC and interprofessional education, ongoing challenges, and the future direction for professional growth. Results indicated that despite regular clinical practice collaboration, participants have a limited understanding of AAs in terms of their educational prerequisites, scope of practice, and roles. One reason for this lack of understanding is that there is a high variability of titles and clinical duties for non-physician anesthesia providers. The diverse range of anesthesia services provided by AAs can also become a barrier to the full understanding of their scope of practice and roles. The limited understanding of the AA role was reported as one of AAs' ongoing challenges. It prevents AAs from realising their full scope of practice. Participants suggested that AAs' professional growth should focus on promoting and expanding their role. Understanding other healthcare professionals' perceptions of AAs will assist them to become better ambassadors for their role, and to more effectively promote and practice IPC. Ultimately, this will result in improved interprofessional teamwork to deliver effective and efficient patient care.
Jones, Caroline O H; Wasunna, Beatrice; Sudoi, Raymond; Githinji, Sophie; Snow, Robert W; Zurovac, Dejan
2012-01-01
This paper presents the results of a qualitative study to investigate the perceptions and experiences of health workers involved in a a cluster-randomized controlled trial of a novel intervention to improve health worker malaria case-management in 107 government health facilities in Kenya. The intervention involved sending text-messages about paediatric outpatient malaria case-management accompanied by "motivating" quotes to health workers' mobile phones. Ten malaria messages were developed reflecting recommendations from the Kenyan national guidelines. Two messages were delivered per day for 5 working days and the process was repeated for 26 weeks (May to October 2009). The accompanying quotes were unique to each message. The intervention was delivered to 119 health workers and there were significant improvements in correct artemether-lumefantrine (AL) management both immediately after the intervention (November 2009) and 6 months later (May 2010). In-depth interviews with 24 health workers were undertaken to investigate the possible drivers of this change. The results suggest high acceptance of all components of the intervention, with the active delivery of information in an on the job setting, the ready availability of new and stored text messages and the perception of being kept 'up to date' as important factors influencing practice. Applying the construct of stages of change we infer that in this intervention the SMS messages were operating primarily at the action and maintenance stages of behaviour change achieving their effect by creating an enabling environment and providing a prompt to action for the implementation of case management practices that had already been accepted as the clinical norm by the health workers. Future trials testing the effectiveness of SMS reminders in creating an enabling environment for the establishment of new norms in clinical practice as well as in providing a prompt to action for the implementation of the new case-management guidelines are justified.
Jones, Caroline O. H.; Wasunna, Beatrice; Sudoi, Raymond; Githinji, Sophie; Snow, Robert W.; Zurovac, Dejan
2012-01-01
This paper presents the results of a qualitative study to investigate the perceptions and experiences of health workers involved in a a cluster-randomized controlled trial of a novel intervention to improve health worker malaria case-management in 107 government health facilities in Kenya. The intervention involved sending text-messages about paediatric outpatient malaria case-management accompanied by “motivating” quotes to health workers’ mobile phones. Ten malaria messages were developed reflecting recommendations from the Kenyan national guidelines. Two messages were delivered per day for 5 working days and the process was repeated for 26 weeks (May to October 2009). The accompanying quotes were unique to each message. The intervention was delivered to 119 health workers and there were significant improvements in correct artemether-lumefantrine (AL) management both immediately after the intervention (November 2009) and 6 months later (May 2010). In-depth interviews with 24 health workers were undertaken to investigate the possible drivers of this change. The results suggest high acceptance of all components of the intervention, with the active delivery of information in an on the job setting, the ready availability of new and stored text messages and the perception of being kept ‘up to date’ as important factors influencing practice. Applying the construct of stages of change we infer that in this intervention the SMS messages were operating primarily at the action and maintenance stages of behaviour change achieving their effect by creating an enabling environment and providing a prompt to action for the implementation of case management practices that had already been accepted as the clinical norm by the health workers. Future trials testing the effectiveness of SMS reminders in creating an enabling environment for the establishment of new norms in clinical practice as well as in providing a prompt to action for the implementation of the new case-management guidelines are justified. PMID:22719911
Determining the disease management process for epileptic patients: A qualitative study
Hosseini, Nazafarin; Sharif, Farkhondeh; Ahmadi, Fazlollah; Zare, Mohammad
2016-01-01
Background: Epilepsy exposes patients to many physical, social, and emotional challenges. Thus, it seems to portray a complex picture and needs holistic care. Medical treatment and psychosocial part of epilepsy remain central to managing and improving the patient's qualify of life through team efforts. Some studies have shown the dimensions of self-management, but its management process of epilepsy patients, especially in Iran, is not clear. This study aimed to determine the disease management process in patients with epilepsy in Iran. Materials and Methods: This qualitative approach and grounded theory study was conducted from January 2009 to February 2012 in Isfahan city (Iran). Thirty-two participants were recruited by the goal-oriented, and snowball sample selection and theoretical sampling methods. After conducting a total of 43 in-depth interviews with the participants, the researchers reached data saturation. Data were analyzed using Strauss and Corbin method. Results: With a focus on disease management process, researchers found three main themes and seven sub-themes as a psychosocial process (PSP). The main themes were: perception of threat to self-identity, effort to preserve self-identity, and burn out. The psychosocial aspect of the disease generated one main variable “the perception of identity loss” and one central variable “searching for self-identity.” Conclusions: Participants attributed threat to self-identity and burn out to the way their disease was managed requiring efforts to preserve their identity. Recommendations consist of support programs and strategies to improve the public perception of epilepsy in Iran, help patients accept their condition and preserve self-identity, and most importantly, enhance medical management of epilepsy. PMID:26985223
Meyer, Erika; Bunnell, Rebecca; Bio, Franklin A; Jalloh, Mohammad B; Sengeh, Paul; Hageman, Kathy M; Carroll, Dianna D; Conteh, Lansana; Morgan, Oliver
2018-01-01
Social mobilisation and risk communication were essential to the 2014–2015 West African Ebola response. By March 2015, >8500 Ebola cases and 3370 Ebola deaths were confirmed in Sierra Leone. Response efforts were focused on ‘getting to zero and staying at zero’. A critical component of this plan was to deepen and sustain community engagement. Several national quantitative studies conducted during this time revealed Ebola knowledge, personal prevention practices and traditional burial procedures improved as the outbreak waned, but healthcare system challenges were also noted. Few qualitative studies have examined these combined factors, along with survivor stigma during periods of ongoing transmission. To obtain an in-depth understanding of people’s perceptions, attitudes and behaviours associated with Ebola transmission risks, 27 focus groups were conducted between April and May 2015 with adult Sierra Leonean community members on: trust in the healthcare system, interactions with Ebola survivors, impact of Ebola on lives and livelihood, and barriers and facilitators to ending the outbreak. Participants perceived that as healthcare practices and facilities improved, so did community trust. Resource management remained a noted concern. Perceptions of survivors ranged from sympathy and empathy to fear and stigmatisation. Barriers included persistent denial of ongoing Ebola transmission, secret burials and movement across porous borders. Facilitators included personal protective actions, consistent messaging and the inclusion of women and survivors in the response. Understanding community experiences during the devastating Ebola epidemic provides practical lessons for engaging similar communities in risk communication and social mobilisation during future outbreaks and public health emergencies. PMID:29629189
Ugandan opinion-leaders' knowledge and perceptions of unsafe abortion.
Moore, Ann M; Kibombo, Richard; Cats-Baril, Deva
2014-10-01
While laws in Uganda surrounding abortion remain contradictory, a frequent interpretation of the law is that abortion is only allowed to save the woman's life. Nevertheless abortion occurs frequently under unsafe conditions at a rate of 54 abortions per 1000 women of reproductive age annually, taking a large toll on women's health. There are an estimated 148,500 women in Uganda who experience abortion complications annually. Understanding opinion leaders' knowledge and perceptions about unsafe abortion is critical to identifying ways to address this public health issue. We conducted in-depth, semi-structured interviews with 41 policy-makers, cultural leaders, local politicians and leaders within the health care sector in 2009-10 at the national as well as district (Bushenyi, Kamuli and Lira) level to explore their knowledge and perceptions of unsafe abortion and the potential for policy to address this issue. Only half of the sample knew the current law regulating abortion in Uganda. Respondents understood that the result of the current abortion restrictions included long-term health complications, unwanted children and maternal death. Perceived consequences of increasing access to safe abortion included improved health as well as overuse of abortion, marital conflict and less reliance on preventive behaviour. Opinion leaders expressed the most support for legalization of abortion in cases of rape when the perpetrator was unknown. Understanding opinion leaders' perspectives on this politically sensitive topic provides insight into the policy context of abortion laws, drivers behind maintaining the status quo, and ways to improve provision under the law: increase education among providers and opinion leaders. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine © The Author 2013; all rights reserved.
Digital science games' impact on sixth and eighth graders' perceptions of science
NASA Astrophysics Data System (ADS)
Peng, Li-Wei
2009-12-01
The quasi-experimental study investigated sixth and eighth graders' perceptions of science with gender, grade levels, and educational experiences as the variables. The Theory of Planned Behavior (Ajzen, 1985) claims that attitude toward the behavior, subjective norm, and perceived behavioral control play a major role in people's intentions, and these intentions ultimately impact their behavior. The study adopted a quantitative research approach by conducting a science perceptions survey for examining students' self-efficacy in learning science (i.e., perceived behavioral control), value of science (i.e., attitude toward the behavior), motivation in science (i.e., attitude toward the behavior), and perceptions of digital science games in science classes (i.e., perceived behavioral control). A total of 255 participants' responses from four rural Appalachian middle school science classrooms in southeastern Ohio were analyzed through a three-way ANCOVA factorial pre-test and post-test data analysis with experimental and comparison groups. Additionally, the study applied a semi-structured, in-depth interview as a qualitative research approach to further examine STEAM digital science games' and Fellows' impact on students' perceptions of science. Eight students in the experimental group were interviewed. Interview data were analyzed with an inductive method. The results found in the three-way ANCOVA data analysis indicated that the diversity of educational experiences was a significant factor that impacted sixth and eighth graders' perceptions of science. Additionally, the interaction of gender and educational experiences was another significant factor that impacted sixth and eighth graders' perceptions of science. The findings of the two short-answer questions identified the reasons why the participants liked or disliked science, as well as why the participants would or would not choose a career in science. The conclusions of the semi-structured, in-depth interview supported that the interviewees' perceptions of the STEAM digital science games and Fellows ranged from neutral to positive. Seven out of eight of the interviewees commented that the STEAM digital science games and Fellows enhanced the interviewees' perceptions of science and their choice of careers. Five out of eight of the interviewees intended to have careers in science.
Creating a Vision Channel for Observing Deep-Seated Anatomy in Medical Augmented Reality
NASA Astrophysics Data System (ADS)
Wimmer, Felix; Bichlmeier, Christoph; Heining, Sandro M.; Navab, Nassir
The intent of medical Augmented Reality (AR) is to augment the surgeon's real view on the patient with the patient's interior anatomy resulting from a suitable visualization of medical imaging data. This paper presents a fast and user-defined clipping technique for medical AR allowing for cutting away any parts of the virtual anatomy and images of the real part of the AR scene hindering the surgeon's view onto the deepseated region of interest. Modeled on cut-away techniques from scientific illustrations and computer graphics, the method creates a fixed vision channel to the inside of the patient. It enables a clear view on the focussed virtual anatomy and moreover improves the perception of spatial depth.
Index to FAA Office of Aerospace Medicine Reports: 1961 Through 2006
2007-01-01
Research Branch) has always comprised a group of research teams identified primarily by their specialty func- tions. In 2001, CAMI was renamed the...implications of unmanned aircraft accidents: Flight control problems. Above: This is an entry from the Chronological Index of research reports, shown... control research task. AD660198 65-32 Gogel WC, Mertens HW: Problems in depth perception: A method of simulating objects moving in depth. AD660171 1966 66
Seeing the tipping point: Balance perception and visual shape.
Firestone, Chaz; Keil, Frank C
2016-07-01
In a brief glance at an object or shape, we can appreciate a rich suite of its functional properties, including the organization of the object's parts, its optimal contact points for grasping, and its center of mass, or balancing point. However, in the real world and the laboratory, balance perception shows systematic biases whereby observers may misjudge a shape's center of mass by a severe margin. Are such biases simply quirks of physical reasoning? Or might they instead reflect more fundamental principles of object representation? Here we demonstrate systematically biased center-of-mass estimation for two-dimensional (2D) shapes (Study 1) and advance a surprising explanation of such biases. We suggest that the mind implicitly represents ordinary 2D shapes as rich, volumetric, three-dimensional (3D) objects, and that these "inflated" shape representations intrude on and bias perception of the 2D shape's geometric properties. Such "inflation" is a computer-graphics technique for segmenting shapes into parts, and we show that a model derived from this technique best accounts for the biases in center-of-mass estimation in Study 1. Further supporting this account, we show that reducing the need for inflated shape representations diminishes such biases: Center-of-mass estimation improved when cues to shapehood were attenuated (Study 2) and when shapes' depths were explicitly depicted using real-life objects laser-cut from wood (Study 3). We suggest that the technique of shape inflation is actually implemented in the mind; thus, biases in our impressions of balance reflect a more general functional characteristic of object perception. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Therapists' Perceptions of Their Encounter With Sex Offenders.
Elias, Haneen; Haj-Yahia, Muhammad M
2017-08-01
Despite the increasing interest in therapists' responses to their encounter with sex offenders, there is a lack of research on their subjective perceptions of this encounter and on their experience working with this client population. The study presented in this article is part of a larger qualitative research project conducted among 19 social workers (12 were women and 7 were men; their ages ranged from 30 to 66 years; 15 of them were Jewish and 4 were Arab). In-depth semi-structured interviews were conducted to examine their attitudes toward and perceptions of their encounter with sex offenders. The questions related to the therapists' perceptions regarding motives for committing sex offenses, therapists' perceptions of sex offenders, therapists' perceptions of the victims of sex offenders, and therapists' perceptions of the nature of their professional role. In this article, emphasis is placed on the development and changes of the therapists' perceptions following that encounter. The following five major domains of perceptions were revealed in the study: Therapists' perceptions of the offenders' personal motives for committing sex offenses, therapists' perceptions of sex offenders, therapists' perceptions of the experience of victimization, the process of changing perceptions, and the nature of the therapists' role. The results are discussed in light of Ajzen's conceptualization of the process of acquiring beliefs. The limitations of the study as well as its implications for future research and for shaping the perceptions of therapists toward sex offenders are discussed.
Samsiah, A.; Othman, Noordin; Jamshed, Shazia; Hassali, Mohamed Azmi
2016-01-01
Objective To explore and understand participants’ perceptions and attitudes towards the reporting of medication errors (MEs). Methods A qualitative study using in-depth interviews of 31 healthcare practitioners from nine publicly funded, primary care clinics in three states in peninsular Malaysia was conducted for this study. The participants included family medicine specialists, doctors, pharmacists, pharmacist assistants, nurses and assistant medical officers. The interviews were audiotaped and transcribed verbatim. Analysis of the data was guided by the framework approach. Results Six themes and 28 codes were identified. Despite the availability of a reporting system, most of the participants agreed that MEs were underreported. The nature of the error plays an important role in determining the reporting. The reporting system, organisational factors, provider factors, reporter’s burden and benefit of reporting also were identified. Conclusions Healthcare practitioners in primary care clinics understood the importance of reporting MEs to improve patient safety. Their perceptions and attitudes towards reporting of MEs were influenced by many factors which affect the decision-making process of whether or not to report. Although the process is complex, it primarily is determined by the severity of the outcome of the errors. The participants voluntarily report the errors if they are familiar with the reporting system, what error to report, when to report and what form to use. PMID:27906960
School experiences of early adolescent Latinos/as at risk for emotional and behavioral disorders.
Balagna, Ryan M; Young, Ellie L; Smith, Timothy B
2013-06-01
Previous research has shown that Latino/a middle school students exhibiting emotional or behavioral disturbance are at risk for undesirable academic outcomes. The purpose of this study was to understand the perceptions and experiences of at-risk Latino/a students to identify ways to improve interventions targeted to promote their academic retention and success. Participants included 11 Latino/a students between the ages of 11 and 13 years, 8 males and 3 females, who were screened as being at risk for behavior disorders using the Systematic Screening for Behavior Disorders (SSBD). These students shared their perceptions and experiences of schooling during in-depth qualitative interviews. Interpretative phenomenological analysis (IPA) was used to understand how these students made sense of their school experiences. Students' descriptions tended to be contextualized within relationships with peers, teachers, and family members. Many students shared experiences of being the target of overt racism and microaggressions from peers. Students believed they were more likely to be successful in school when teachers displayed flexibility with deadlines, provided extra help, and communicated a sense of warmth and caring. The data from this study suggested that school psychologists can benefit from attending to at-risk students' perceptions, which, in the context of this study, would require facilitating an inclusive school climate, fostering effective teacher and student relationships, and facilitating parent-teacher relationships during the difficult transition from elementary to middle school.
Matovu, Joseph Kb; Buregyeya, Esther; Arinaitwe, Jim; Wanyenze, Rhoda K
2017-11-01
In 2015, the World Health Organization reported that more than 60 million people were tested for HIV in 122 low- and middle-income countries between 2010 and 2014. Despite this level of progress, over 40% of people living with HIV remain unaware of their HIV status. This calls for innovative approaches to improve uptake of HIV testing services, including use of HIV self-test (HIVST) kits. We conducted a cross-sectional, qualitative study to assess pregnant women and their male partners' perceptions regarding female partner-delivered HIVST kits. This study was conducted at two health facilities in Central Uganda between November and December 2015. Data were collected on pregnant women's willingness to take HIVST kits to their male partners and other household members using eight focus group discussions and 30 in-depth interviews. Data were analyzed following a thematic framework approach. Overall, pregnant women were willing to take HIVST kits to their partners and other household members, with the exception of their cowives. Male partners were willing to use HIVST kits brought by their female partners. Our findings suggest that secondary distribution of HIVST kits through female partners is acceptable and has the potential to improve male partner and household-member HIV testing.
Inoue, Kumiyo; Kelly, Marguerite; Barratt, Alexandra; Bateson, Deborah; Rutherford, Alison; Black, Kirsten I; Stewart, Mary; Richters, Juliet
2017-04-01
Few studies have explored Australian women's understandings of contraception. This study examined the attitudes towards, and understandings of, the subdermal contraceptive implant expressed by women living in New South Wales (NSW), Australia. As part of a larger qualitative study using in-depth, open-ended interviews in 2012-2013 with women aged 16-49 years who had ever used contraception ( n =94), 65 interviews from women who discussed or mentioned the subdermal implant, but had not previously used the device, were examined and analysed using thematic analysis. The emergent themes were: satisfaction with current method; weak personal opinions and ambivalence; uncertainty due to specific concerns; and strong negative reactions - fear and dislike. Although there were a few positive perceptions expressed by women who had never used the subdermal implant, for the majority of women the perception was predominantly negative. Women tended to form negative impressions from the stories of other women about the subdermal implant. Interventions to enhance evidence-informed awareness of the relative advantages and disadvantages of the implant - for example, improved access to supportive contraceptive counselling - need investigation in the Australian context. Avenues to improve women's perceived control over the device could also be usefully investigated. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Developmental milestones record - 9 months
... Feeds self with fingers Throws or shakes objects SENSORY AND COGNITIVE SKILLS The 9-month-old typically: Babbles Has separation anxiety and may cling to parents Is developing depth perception Understands that objects continue to exist, even when ...
Flood Realities, Perceptions and the Depth of Divisions on Climate
Hamilton, Lawrence C; Wake, Cameron P; Hartter, Joel; Safford, Thomas G; Puchlopek, Alli J
2016-01-01
Research has led to broad agreement among scientists that anthropogenic climate change is happening now and likely to worsen. In contrast to scientific agreement, US public views remain deeply divided, largely along ideological lines. Science communication has been neutralised in some arenas by intense counter-messaging, but as adverse climate impacts become manifest they might intervene more persuasively in local perceptions. We look for evidence of this occurring with regard to realities and perceptions of flooding in the northeastern US state of New Hampshire. Although precipitation and flood damage have increased, with ample news coverage, most residents do not see a trend. Nor do perceptions about past and future local flooding correlate with regional impacts or vulnerability. Instead, such perceptions follow ideological patterns resembling those of global climate change. That information about the physical world can be substantially filtered by ideology is a common finding from sociological environment/society research. PMID:27818533
Kumbani, Lily C; Chirwa, Ellen; Malata, Address; Odland, Jon Øyvind; Bjune, Gunnar
2012-11-16
Malawi has a high perinatal mortality rate of 40 deaths per 1,000 births. To promote neonatal health, the Government of Malawi has identified essential health care packages for improving maternal and neonatal health in health care facilities. However, regardless of the availability of health services, women's perceptions of the care is important as it influences whether the women will or will not use the services. In Malawi 95% of pregnant women receive antenatal care from skilled attendants, but the number is reduced to 71% deliveries being conducted by skilled attendants. The objective of this study was to describe women's perceptions on perinatal care among the women delivered at a district hospital. A descriptive study design with qualitative data collection and analysis methods. Data were collected through face-to-face in-depth interviews using semi-structured interview guides collecting information on women's perceptions on perinatal care. A total of 14 in depth interviews were conducted with women delivering at Chiradzulu District Hospital from February to March 2011. The women were asked how they perceived the care they received from health workers during antepartum, intrapartum and postpartum. They were also asked about the information they received during provision of care. Data were manually analyzed using thematic analysis. Two themes from the study were good care and unsatisfactory care. Subthemes under good care were: respect, confidentiality, privacy and normal delivery. Providers' attitude, delay in providing care, inadequate care, and unavailability of delivery attendants were subthemes under unsatisfactory care. Although the results show that women wanted to be well received at health facilities, respected, treated with kindness, dignity and not shouted at, they were not critical of the care they received. The women did not know the quality of care to expect because they were not well informed. The women were not critical of the care they received because they were not aware of the standard of care. Instead they had low expectations. Health workers have a responsibility to inform women and their families about the care that women should expect. There is also a need for standardization of the antenatal information that is provided.
Sanusi, A; Akinyemi, Oluwaseun O; Onoviran, Oghemetega O
2014-12-01
Male involvement is crucial to female contraceptive use. This study examined how male knowledge and cultural perceptions of modern female contraceptives influence involvement in contraceptive use. A cross-sectional survey of 389 men from Ayete, Nigeria was used to regress a continuous male involvement score on demographic variables, knowledge of at least one method of modern female contraception and a scored male perception variable using Ordinary Least Squares regression. Controlling for perception, the knowledge of at least one method of modern female contraception was not significantly associated with a change in male involvement (p=0.264). Increasing positive perception was associated with higher male involvement scores (p=0.001). Higher educated males, those with a current desire to have children and males whose partners were currently using a method had greater male involvement scores (p<0.05). Policy and intervention efforts should be focused on changing cultural perceptions, in addition to providing in-depth knowledge of contraceptive methods.
ERIC Educational Resources Information Center
Hardman, Brenda Kay
2011-01-01
Teachers' perceptions of their school leaders influence student achievement in their schools. The extent of this influence is examined in this study. This quantitative study examined teachers' perceptions of the leadership style of their principals as transformational, transactional or passive-avoidant in improving and non-improving schools in…
Hollada, Jacqueline; Williams, Kendra N; Miele, Catherine H; Danz, David; Harvey, Steven A; Checkley, William
2017-02-13
Many households in low- and middle-income countries cook with inefficient biomass-burning stoves, which cause high levels of household air pollution and threaten long-term health. Although clean stoves and fuels are available, uptake and consistent use has been low. Using observations and in-depth interviews, we assessed the attitudes, preferences, and beliefs about traditional versus liquefied petroleum gas (LPG) stoves in rural Puno, Peru. A total of 31 in-depth interviews were conducted with primary cooks and their families, health workers, community leaders, and improved stove contractors. Six in-home observations of meal preparation were also conducted. Six major barriers to consistent use of clean stoves were identified: (1) perceived differences in food taste and nutrition by stove type; (2) cooking niches filled by different stoves; (3) social norms related to cooking practices; (4) safety concerns; (5) comparative costs of using different stoves; and (6) lack of awareness and concern about long-term health risks. These findings suggest that to successfully reduce household air pollution, clean cooking programs and policies must consider the many factors influencing adoption beyond health, such as cost, taste, fears, and cultural traditions. These factors could be incorporated into community-based and national efforts to scale-up sustained and exclusive adoption of clean cooking.
Hollada, Jacqueline; Williams, Kendra N.; Miele, Catherine H.; Danz, David; Harvey, Steven A.; Checkley, William
2017-01-01
Many households in low- and middle-income countries cook with inefficient biomass-burning stoves, which cause high levels of household air pollution and threaten long-term health. Although clean stoves and fuels are available, uptake and consistent use has been low. Using observations and in-depth interviews, we assessed the attitudes, preferences, and beliefs about traditional versus liquefied petroleum gas (LPG) stoves in rural Puno, Peru. A total of 31 in-depth interviews were conducted with primary cooks and their families, health workers, community leaders, and improved stove contractors. Six in-home observations of meal preparation were also conducted. Six major barriers to consistent use of clean stoves were identified: (1) perceived differences in food taste and nutrition by stove type; (2) cooking niches filled by different stoves; (3) social norms related to cooking practices; (4) safety concerns; (5) comparative costs of using different stoves; and (6) lack of awareness and concern about long-term health risks. These findings suggest that to successfully reduce household air pollution, clean cooking programs and policies must consider the many factors influencing adoption beyond health, such as cost, taste, fears, and cultural traditions. These factors could be incorporated into community-based and national efforts to scale-up sustained and exclusive adoption of clean cooking. PMID:28208813
Index to FAA Office of Aerospace Medicine Reports: 1961 Through 2012
2013-01-01
air traffic control research task. AD660198 65-32 Gogel WC, Mertens HW: Problems in depth perception: A method of simulating objects moving in depth...ADA092529/7 80-14 Smith RC: Stress, anxiety, and the air traffic control specialist: Some conclusions from a decade of research . ADA093266/5 80-15...PS, Manning CA: Selection of air traffic controllers for automated systems: applications from current research . ADA230058 90-14 Parker JF Jr, Shepherd
Perception of stochastic envelopes by normal-hearing and cochlear-implant listeners
Gomersall, Philip A.; Turner, Richard E.; Baguley, David M.; Deeks, John M.; Gockel, Hedwig E.; Carlyon, Robert P.
2016-01-01
We assessed auditory sensitivity to three classes of temporal-envelope statistics (modulation depth, modulation rate, and comodulation) that are important for the perception of ‘sound textures’. The textures were generated by a probabilistic model that prescribes the temporal statistics of a selected number of modulation envelopes, superimposed onto noise carriers. Discrimination thresholds were measured for normal-hearing (NH) listeners and users of a MED-EL pulsar cochlear implant (CI), for separate manipulations of the average rate and modulation depth of the envelope in each frequency band of the stimulus, and of the co-modulation between bands. Normal-hearing (NH) listeners' discrimination of envelope rate was similar for baseline modulation rates of 5 and 34 Hz, and much poorer than previously reported for sinusoidally amplitude-modulated sounds. In contrast, discrimination of model parameters that controlled modulation depth was poorer at the lower baseline rate, consistent with the idea that, at the lower rate, subjects get fewer ‘looks’ at the relevant information when comparing stimuli differing in modulation depth. NH listeners could discriminate differences in co-modulation across bands; a multidimensional scaling study revealed that this was likely due to genuine across-frequency processing, rather than within-channel cues. CI users' discrimination performance was worse overall than for NH listeners, but showed a similar dependence on stimulus parameters. PMID:26706708
Working memory training to improve speech perception in noise across languages
Ingvalson, Erin M.; Dhar, Sumitrajit; Wong, Patrick C. M.; Liu, Hanjun
2015-01-01
Working memory capacity has been linked to performance on many higher cognitive tasks, including the ability to perceive speech in noise. Current efforts to train working memory have demonstrated that working memory performance can be improved, suggesting that working memory training may lead to improved speech perception in noise. A further advantage of working memory training to improve speech perception in noise is that working memory training materials are often simple, such as letters or digits, making them easily translatable across languages. The current effort tested the hypothesis that working memory training would be associated with improved speech perception in noise and that materials would easily translate across languages. Native Mandarin Chinese and native English speakers completed ten days of reversed digit span training. Reading span and speech perception in noise both significantly improved following training, whereas untrained controls showed no gains. These data suggest that working memory training may be used to improve listeners' speech perception in noise and that the materials may be quickly adapted to a wide variety of listeners. PMID:26093435
Working memory training to improve speech perception in noise across languages.
Ingvalson, Erin M; Dhar, Sumitrajit; Wong, Patrick C M; Liu, Hanjun
2015-06-01
Working memory capacity has been linked to performance on many higher cognitive tasks, including the ability to perceive speech in noise. Current efforts to train working memory have demonstrated that working memory performance can be improved, suggesting that working memory training may lead to improved speech perception in noise. A further advantage of working memory training to improve speech perception in noise is that working memory training materials are often simple, such as letters or digits, making them easily translatable across languages. The current effort tested the hypothesis that working memory training would be associated with improved speech perception in noise and that materials would easily translate across languages. Native Mandarin Chinese and native English speakers completed ten days of reversed digit span training. Reading span and speech perception in noise both significantly improved following training, whereas untrained controls showed no gains. These data suggest that working memory training may be used to improve listeners' speech perception in noise and that the materials may be quickly adapted to a wide variety of listeners.
Segregation of Form, Color, Movement, and Depth: Anatomy, Physiology, and Perception.
ERIC Educational Resources Information Center
Livingstone, Margaret; Hubel, David
1988-01-01
Summarizes the anatomical, physiological, and psychological evidence related to the primate visual system. States that comparison of perceptual abilities with the electrophysiological properties of neurons may help deduce functions of visual areas. (RT)
De Martino, Federico; Moerel, Michelle; Ugurbil, Kamil; Goebel, Rainer; Yacoub, Essa; Formisano, Elia
2015-12-29
Columnar arrangements of neurons with similar preference have been suggested as the fundamental processing units of the cerebral cortex. Within these columnar arrangements, feed-forward information enters at middle cortical layers whereas feedback information arrives at superficial and deep layers. This interplay of feed-forward and feedback processing is at the core of perception and behavior. Here we provide in vivo evidence consistent with a columnar organization of the processing of sound frequency in the human auditory cortex. We measure submillimeter functional responses to sound frequency sweeps at high magnetic fields (7 tesla) and show that frequency preference is stable through cortical depth in primary auditory cortex. Furthermore, we demonstrate that-in this highly columnar cortex-task demands sharpen the frequency tuning in superficial cortical layers more than in middle or deep layers. These findings are pivotal to understanding mechanisms of neural information processing and flow during the active perception of sounds.
Murphy, Sue; Imam, Bita; MacIntyre, Donna L
2015-01-01
To compare the use of standardized patients (SPs) and volunteer patients (VPs) for physical therapy students' interviewing practice in terms of students' perception and overall costs. Students in the Master of Physical Therapy programme (n=80) at a Canadian university were divided into 20 groups of 4 and were randomly assigned to interview either an SP (10 groups) or a VP (10 groups). Students completed a survey about their perception of the usefulness of the activity and the ease and depth of information extraction. Survey responses as well as costs of the interview exercise were compared between SP and VP groups. No statistically significant between-groups difference was found for the majority of survey items. The cost of using an SP was $148, versus $50 for a VP. Students' perceptions of the usefulness of the activity in helping them to develop their interview skills and of the ease and depth of extracting information were similar for both SPs and VPs. Because the cost of using an SP is about three times that of using a VP, using VPs seem to be a more cost-effective option.
Bandesha, G; Litva, A
2005-09-01
The new public health rejects old individualist attempts at improving health and embraces community-based approaches in reducing health inequalities. Primary Care Trusts in England face the challenge of converting community participation in health into reality. This study explores differences in perception of participation between lay and professional stakeholders of a community health project for a South Asian population in Greater Manchester. In-depth interviews and focus groups were used to explore the views of professional and lay stakeholders. All data were audio-taped, transcribed and analysed for emerging themes using a qualitative framework. Professionals talked of working in partnership with the community but lay stakeholders did not feel that they had control over the project. There were problems in engaging the community and local health professionals in the project. Lack of cultural awareness hampered participation in the project. There was agreement that the project improved the self-confidence of participants and created a more informed population. However, there was little support for claims of improvements in social cohesion and changes in lifestyle directly as a result of the project. Converting the rhetoric of community participation in health into reality is a greater challenge than was envisaged by policy makers. Marginalized communities may not be willing participants and issues of language and cultural sensitivity are important. Project outcomes need to be agreed to ensure projects are evaluated appropriately. Projects with South Asian communities should not be seen to be dealing with all 'ethnic health' issues without addressing changes in statutory organizations and other wider social determinants of health.
A neural model of visual figure-ground segregation from kinetic occlusion.
Barnes, Timothy; Mingolla, Ennio
2013-01-01
Freezing is an effective defense strategy for some prey, because their predators rely on visual motion to distinguish objects from their surroundings. An object moving over a background progressively covers (deletes) and uncovers (accretes) background texture while simultaneously producing discontinuities in the optic flow field. These events unambiguously specify kinetic occlusion and can produce a crisp edge, depth perception, and figure-ground segmentation between identically textured surfaces--percepts which all disappear without motion. Given two abutting regions of uniform random texture with different motion velocities, one region appears to be situated farther away and behind the other (i.e., the ground) if its texture is accreted or deleted at the boundary between the regions, irrespective of region and boundary velocities. Consequently, a region with moving texture appears farther away than a stationary region if the boundary is stationary, but it appears closer (i.e., the figure) if the boundary is moving coherently with the moving texture. A computational model of visual areas V1 and V2 shows how interactions between orientation- and direction-selective cells first create a motion-defined boundary and then signal kinetic occlusion at that boundary. Activation of model occlusion detectors tuned to a particular velocity results in the model assigning the adjacent surface with a matching velocity to the far depth. A weak speed-depth bias brings faster-moving texture regions forward in depth in the absence of occlusion (shearing motion). These processes together reproduce human psychophysical reports of depth ordering for key cases of kinetic occlusion displays. Copyright © 2012 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Alibakhshi, Goudarz; Dehvari, Najibeh
2015-01-01
English, particularly regarding a foreign language teachers' professional development, has been studied in depth. However, it is not known how Iranian English as a foreign language teachers perceive continuing professional development. This study explored the perceptions of Iranian English as a foreign language teachers of continuing professional…
Absolute Depth Sensitivity in Cat Primary Visual Cortex under Natural Viewing Conditions.
Pigarev, Ivan N; Levichkina, Ekaterina V
2016-01-01
Mechanisms of 3D perception, investigated in many laboratories, have defined depth either relative to the fixation plane or to other objects in the visual scene. It is obvious that for efficient perception of the 3D world, additional mechanisms of depth constancy could operate in the visual system to provide information about absolute distance. Neurons with properties reflecting some features of depth constancy have been described in the parietal and extrastriate occipital cortical areas. It has also been shown that, for some neurons in the visual area V1, responses to stimuli of constant angular size differ at close and remote distances. The present study was designed to investigate whether, in natural free gaze viewing conditions, neurons tuned to absolute depths can be found in the primary visual cortex (area V1). Single-unit extracellular activity was recorded from the visual cortex of waking cats sitting on a trolley in front of a large screen. The trolley was slowly approaching the visual scene, which consisted of stationary sinusoidal gratings of optimal orientation rear-projected over the whole surface of the screen. Each neuron was tested with two gratings, with spatial frequency of one grating being twice as high as that of the other. Assuming that a cell is tuned to a spatial frequency, its maximum response to the grating with a spatial frequency twice as high should be shifted to a distance half way closer to the screen in order to attain the same size of retinal projection. For hypothetical neurons selective to absolute depth, location of the maximum response should remain at the same distance irrespective of the type of stimulus. It was found that about 20% of neurons in our experimental paradigm demonstrated sensitivity to particular distances independently of the spatial frequencies of the gratings. We interpret these findings as an indication of the use of absolute depth information in the primary visual cortex.
NASA Astrophysics Data System (ADS)
Lu, Zhong-Lin; Sperling, George
2002-10-01
Two theories are considered to account for the perception of motion of depth-defined objects in random-dot stereograms (stereomotion). In the LuSperling three-motion-systems theory J. Opt. Soc. Am. A 18 , 2331 (2001), stereomotion is perceived by the third-order motion system, which detects the motion of areas defined as figure (versus ground) in a salience map. Alternatively, in his comment J. Opt. Soc. Am. A 19 , 2142 (2002), Patterson proposes a low-level motion-energy system dedicated to stereo depth. The critical difference between these theories is the preprocessing (figureground based on depth and other cues versus simply stereo depth) rather than the motion-detection algorithm itself (because the motion-extraction algorithm for third-order motion is undetermined). Furthermore, the ability of observers to perceive motion in alternating feature displays in which stereo depth alternates with other features such as texture orientation indicates that the third-order motion system can perceive stereomotion. This reduces the stereomotion question to Is it third-order alone or third-order plus dedicated depth-motion processing? Two new experiments intended to support the dedicated depth-motion processing theory are shown here to be perfectly accounted for by third-order motion, as are many older experiments that have previously been shown to be consistent with third-order motion. Cyclopean and rivalry images are shown to be a likely confound in stereomotion studies, rivalry motion being as strong as stereomotion. The phase dependence of superimposed same-direction stereomotion stimuli, rivalry stimuli, and isoluminant color stimuli indicates that these stimuli are processed in the same (third-order) motion system. The phase-dependence paradigm Lu and Sperling, Vision Res. 35 , 2697 (1995) ultimately can resolve the question of which types of signals share a single motion detector. All the evidence accumulated so far is consistent with the three-motion-systems theory. 2002 Optical Society of America
Tomonaga, Masaki; Imura, Tomoko
2010-07-08
Humans readily perceive whole shapes as intact when some portions of these shapes are occluded by another object. This type of amodal completion has also been widely reported among nonhuman animals and is related to pictorial depth perception. However, the effect of a cast shadow, a critical pictorial-depth cue for amodal completion has been investigated only rarely from the comparative-cognitive perspective. In the present study, we examined this effect in chimpanzees and humans. Chimpanzees were slower in responding to a Pacman target with an occluding square than to the control condition, suggesting that participants perceptually completed the whole circle. When a cast shadow was added to the square, amodal completion occurred in both species. On the other hand, however, critical differences between the species emerged when the cast shadow was added to the Pacman figure, implying that Pacman was in the sky casting a shadow on the square. The cast shadow prevented, to a significant extent, compulsory amodal completion in humans, but had no effect on chimpanzees. These results suggest that cast shadows played a critical role in enabling humans to infer the spatial relationship between Pacman and the square. For chimpanzees, however, a cast shadow may be perceived as another "object". A limited role for cast shadows in the perception of pictorial depth has also been reported with respect to human cognitive development. Further studies on nonhuman primates using a comparative-developmental perspective will clarify the evolutionary origin of the role of cast shadows in visual perception.
van der Beek, Feddo B; Briaire, Jeroen J; van der Marel, Kim S; Verbist, Berit M; Frijns, Johan H M
2016-01-01
In this study, the effects of the intracochlear position of cochlear implants on the clinical fitting levels were analyzed. A total of 130 adult subjects who used a CII/HiRes 90K cochlear implant with a HiFocus 1/1J electrode were included in the study. The insertion angle and the distance to the modiolus of each electrode contact were determined using high-resolution CT scanning. The threshold levels (T-levels) and maximum comfort levels (M-levels) at 1 year of follow-up were determined. The degree of speech perception of the subjects was evaluated during routine clinical follow-up. The depths of insertion of all the electrode contacts were determined. The distance to the modiolus was significantly smaller at the basal and apical cochlear parts compared with that at the middle of the cochlea (p < 0.05). The T-levels increased toward the basal end of the cochlea (3.4 dB). Additionally, the M-levels, which were fitted in our clinic using a standard profile, also increased toward the basal end, although with a lower amplitude (1.3 dB). Accordingly, the dynamic range decreased toward the basal end (2.1 dB). No correlation was found between the distance to the modiolus and the T-level or the M-level. Furthermore, the correlation between the insertion depth and stimulation levels was not affected by the duration of deafness, age at implantation or the time since implantation. Additionally, the T-levels showed a significant correlation with the speech perception scores (p < 0.05). The stimulation levels of the cochlear implants were affected by the intracochlear position of the electrode contacts, which were determined using postoperative CT scanning. Interestingly, these levels depended on the insertion depth, whereas the distance to the modiolus did not affect the stimulation levels. The T-levels increased toward the basal end of the cochlea. The level profiles were independent of the overall stimulation levels and were not affected by the biographical data of the patients, such as the duration of deafness, age at implantation or time since implantation. Further research is required to elucidate how fitting using level profiles with an increase toward the basal end of the cochlea benefits speech perception. Future investigations may elucidate an explanation for the effects of the intracochlear electrode position on the stimulation levels and might facilitate future improvements in electrode design. © 2016 S. Karger AG, Basel.
Depth cue reliance in surgeons and medical students.
Shah, J; Buckley, D; Frisby, J; Darzi, A
2003-09-01
Depth perception is reduced in endoscopic surgery, although little is known about the effect this has on surgical performance. To assess the role of depth cues, 45 subjects completed tests of depth cue reliance. Surgical skill was assessed using the Minimally Invasive Surgical Trainer-Virtual Reality, a previously validated laparoscopic simulator. We could demonstrate no difference in cue reliance for three depth cues--namely stereo, texture, and outline--between surgeons and medical students. Greater dominance on stereo for medical students was a positive finding and a negative finding for the surgeons when correlated with surgical performance. We suggest that surgeons learn to adapt to the nonstereo environment in MIS, and this is the first study to show evidence of this phenomenon. This difference in stereo reliance is a reflection of the experience that surgeons have with laparoscopy compared with medical students, who have none.
NASA Astrophysics Data System (ADS)
Rosas, Pedro; Wagemans, Johan; Ernst, Marc O.; Wichmann, Felix A.
2005-05-01
A number of models of depth-cue combination suggest that the final depth percept results from a weighted average of independent depth estimates based on the different cues available. The weight of each cue in such an average is thought to depend on the reliability of each cue. In principle, such a depth estimation could be statistically optimal in the sense of producing the minimum-variance unbiased estimator that can be constructed from the available information. Here we test such models by using visual and haptic depth information. Different texture types produce differences in slant-discrimination performance, thus providing a means for testing a reliability-sensitive cue-combination model with texture as one of the cues to slant. Our results show that the weights for the cues were generally sensitive to their reliability but fell short of statistically optimal combination - we find reliability-based reweighting but not statistically optimal cue combination.
Dolgov, Igor; Birchfield, David A; McBeath, Michael K; Thornburg, Harvey; Todd, Christopher G
2009-04-01
Perception of floor-projected moving geometric shapes was examined in the context of the Situated Multimedia Arts Learning Laboratory (SMALLab), an immersive, mixed-reality learning environment. As predicted, the projected destinations of shapes which retreated in depth (proximal origin) were judged significantly less accurately than those that approached (distal origin). Participants maintained similar magnitudes of error throughout the session, and no effect of practice was observed. Shape perception in an immersive multimedia environment is comparable to the real world. One may conclude that systematic exploration of basic psychological phenomena in novel mediated environments is integral to an understanding of human behavior in novel human-computer interaction architectures.
Rhythm Perception and Its Role in Perception and Learning of Dysrhythmic Speech.
Borrie, Stephanie A; Lansford, Kaitlin L; Barrett, Tyson S
2017-03-01
The perception of rhythm cues plays an important role in recognizing spoken language, especially in adverse listening conditions. Indeed, this has been shown to hold true even when the rhythm cues themselves are dysrhythmic. This study investigates whether expertise in rhythm perception provides a processing advantage for perception (initial intelligibility) and learning (intelligibility improvement) of naturally dysrhythmic speech, dysarthria. Fifty young adults with typical hearing participated in 3 key tests, including a rhythm perception test, a receptive vocabulary test, and a speech perception and learning test, with standard pretest, familiarization, and posttest phases. Initial intelligibility scores were calculated as the proportion of correct pretest words, while intelligibility improvement scores were calculated by subtracting this proportion from the proportion of correct posttest words. Rhythm perception scores predicted intelligibility improvement scores but not initial intelligibility. On the other hand, receptive vocabulary scores predicted initial intelligibility scores but not intelligibility improvement. Expertise in rhythm perception appears to provide an advantage for processing dysrhythmic speech, but a familiarization experience is required for the advantage to be realized. Findings are discussed in relation to the role of rhythm in speech processing and shed light on processing models that consider the consequence of rhythm abnormalities in dysarthria.
4D microscope-integrated OCT improves accuracy of ophthalmic surgical maneuvers
NASA Astrophysics Data System (ADS)
Carrasco-Zevallos, Oscar; Keller, Brenton; Viehland, Christian; Shen, Liangbo; Todorich, Bozho; Shieh, Christine; Kuo, Anthony; Toth, Cynthia; Izatt, Joseph A.
2016-03-01
Ophthalmic surgeons manipulate micron-scale tissues using stereopsis through an operating microscope and instrument shadowing for depth perception. While ophthalmic microsurgery has benefitted from rapid advances in instrumentation and techniques, the basic principles of the stereo operating microscope have not changed since the 1930's. Optical Coherence Tomography (OCT) has revolutionized ophthalmic imaging and is now the gold standard for preoperative and postoperative evaluation of most retinal and many corneal procedures. We and others have developed initial microscope-integrated OCT (MIOCT) systems for concurrent OCT and operating microscope imaging, but these are limited to 2D real-time imaging and require offline post-processing for 3D rendering and visualization. Our previously presented 4D MIOCT system can record and display the 3D surgical field stereoscopically through the microscope oculars using a dual-channel heads-up display (HUD) at up to 10 micron-scale volumes per second. In this work, we show that 4D MIOCT guidance improves the accuracy of depth-based microsurgical maneuvers (with statistical significance) in mock surgery trials in a wet lab environment. Additionally, 4D MIOCT was successfully performed in 38/45 (84%) posterior and 14/14 (100%) anterior eye human surgeries, and revealed previously unrecognized lesions that were invisible through the operating microscope. These lesions, such as residual and potentially damaging retinal deformation during pathologic membrane peeling, were visualized in real-time by the surgeon. Our integrated system provides an enhanced 4D surgical visualization platform that can improve current ophthalmic surgical practice and may help develop and refine future microsurgical techniques.
The riches of the cyclopean paradigm
NASA Astrophysics Data System (ADS)
Tyler, Christopher W.
2005-03-01
The cyclopean paradigm introduced by Bela Julesz remains one of the richest probes into the neural organization of sensory processing, by virtue of both its specificity for purely stereoscopic form and the sophistication of the processing required to retrieve it. The introduction of the sinusoidal stereograting showed that the perceptual limitations of human depth processing are very different from those for monocular form. Their use has also revealed the existence of hypercyclopean form channels selective for specific aspects of the monocularly invisible depth form. The natural extension of stereogratings to patches of stereoGabor ripple has allowed the measurement of the summation properties for depth structure, which is specific for narrow horizontal bars in depth. Consideration of the apparent motion between two cyclopean depth structures reveals the existence of a novel surface correspondence problem operating for cyclopean surfaces over time after the binocular correspondence has been solved. Such concepts imply that remains to be discovered about cyclopean stereopsis and its relationship to 3D form perception from other depth cues.
Gil-Pagés, Macarena; Stiles, Robert J; Parks, Christopher A; Neier, Steven C; Radulovic, Maja; Oliveros, Alfredo; Ferrer, Alejandro; Reed, Brendan K; Wilton, Katelynn M; Schrum, Adam G
2013-08-23
There is significant interest in the generation of improved assays to clearly identify experimental mice possessing functional vision, a property that could qualify mice for inclusion in behavioral and neuroscience studies. Widely employed current methods rely on mouse responses to visual cues in assays of reflexes, depth perception, or cognitive memory. However, commonly assessed mouse reflexes can sometimes be ambiguous in their expression, while depth perception assays are sometimes confounded by variation in anxiety responses and exploratory conduct. Furthermore, in situations where experimental groups vary in their cognitive memory capacity, memory assays may not be ideal for assessing differences in vision. We have optimized a non-invasive behavioral assay that relies on an untrained, innate response to identify individual experimental mice possessing functional vision: slow angled-descent forepaw grasping (SLAG). First, we verified that SLAG performance depends on vision and not olfaction. Next, all members of an age-ranged cohort of 158 C57BL/6 mice (57 wild-type, 101 knockout, age range 44-241 days) were assessed for functional vision using the SLAG test without training or conditioning. Subjecting the population to a second innate behavioral test, Dark Chamber preference, corroborated that the functional vision assessment of SLAG was valid. We propose that the SLAG assay is immediately useful to quickly and clearly identify experimental mice possessing functional vision. SLAG is based on a behavioral readout with a significant innate component with no requirement for training. This will facilitate the selection of mice of known sighted status in vision-dependent experiments that focus on other types of behavior, neuroscience, and/or cognitive memory.
Akhtar, Sadaf; Dolan, Alan; Barlow, Jane
2017-04-01
Over the last 20 years, increasing attention has been given to associations between dispositional forgiveness and specific mental health problems. However, few studies have assessed whether forgiving real-life interpersonal hurts may be related to diverse psychological health outcomes. The present study addresses this gap by investigating, in depth, relationships between perceptions about state forgiveness and a variety of mental wellbeing outcomes as well as exploring perceptions about the factors that may modify such effects. Developing an understanding of a forgiveness wellbeing relationship is of relevance to healthcare workers, researchers and policy makers with an interest in improving public health. In-depth semi-structured interviews were conducted, and data were analysed using grounded theory methods. From England and Ireland, eleven adults who were affiliated with religious/spiritual and secular/atheist groups were recruited using purposive and convenience sampling methods. Key themes that appeared to be related to the effects of unforgiveness were: increases in negative affect; reduction in cognitive abilities and barriers to psychological and social growth. For the majority of participants, state forgiveness had strong ties to participants perceived sense of mental wellbeing, including reductions in negative affect, feeling positive emotions, positive relations with others, spiritual growth, a sense of meaning and purpose in life as well as a greater sense of empowerment. The data also revealed a number of factors that may positively or negatively influence a forgiveness-wellbeing link such as: viewing an offender as spiritually similar or different, responsibility/karma, blaming, wanting restitution/apology as well as practices such as meditation and prayer. The findings suggest that forgiving a range of real-life interpersonal offences may be an important determinant of psychological wellbeing, particularly among religious/spiritual populations. Further research is, however, needed.
2013-01-01
Background There is significant interest in the generation of improved assays to clearly identify experimental mice possessing functional vision, a property that could qualify mice for inclusion in behavioral and neuroscience studies. Widely employed current methods rely on mouse responses to visual cues in assays of reflexes, depth perception, or cognitive memory. However, commonly assessed mouse reflexes can sometimes be ambiguous in their expression, while depth perception assays are sometimes confounded by variation in anxiety responses and exploratory conduct. Furthermore, in situations where experimental groups vary in their cognitive memory capacity, memory assays may not be ideal for assessing differences in vision. Results We have optimized a non-invasive behavioral assay that relies on an untrained, innate response to identify individual experimental mice possessing functional vision: slow angled-descent forepaw grasping (SLAG). First, we verified that SLAG performance depends on vision and not olfaction. Next, all members of an age-ranged cohort of 158 C57BL/6 mice (57 wild-type, 101 knockout, age range 44–241 days) were assessed for functional vision using the SLAG test without training or conditioning. Subjecting the population to a second innate behavioral test, Dark Chamber preference, corroborated that the functional vision assessment of SLAG was valid. Conclusions We propose that the SLAG assay is immediately useful to quickly and clearly identify experimental mice possessing functional vision. SLAG is based on a behavioral readout with a significant innate component with no requirement for training. This will facilitate the selection of mice of known sighted status in vision-dependent experiments that focus on other types of behavior, neuroscience, and/or cognitive memory. PMID:23971729
Depth image enhancement using perceptual texture priors
NASA Astrophysics Data System (ADS)
Bang, Duhyeon; Shim, Hyunjung
2015-03-01
A depth camera is widely used in various applications because it provides a depth image of the scene in real time. However, due to the limited power consumption, the depth camera presents severe noises, incapable of providing the high quality 3D data. Although the smoothness prior is often employed to subside the depth noise, it discards the geometric details so to degrade the distance resolution and hinder achieving the realism in 3D contents. In this paper, we propose a perceptual-based depth image enhancement technique that automatically recovers the depth details of various textures, using a statistical framework inspired by human mechanism of perceiving surface details by texture priors. We construct the database composed of the high quality normals. Based on the recent studies in human visual perception (HVP), we select the pattern density as a primary feature to classify textures. Upon the classification results, we match and substitute the noisy input normals with high quality normals in the database. As a result, our method provides the high quality depth image preserving the surface details. We expect that our work is effective to enhance the details of depth image from 3D sensors and to provide a high-fidelity virtual reality experience.
Fowlkes, Charless C.; Banks, Martin S.
2010-01-01
The shape of the contour separating two regions strongly influences judgments of which region is “figure” and which is “ground.” Convexity and other figure–ground cues are generally assumed to indicate only which region is nearer, but nothing about how much the regions are separated in depth. To determine the depth information conveyed by convexity, we examined natural scenes and found that depth steps across surfaces with convex silhouettes are likely to be larger than steps across surfaces with concave silhouettes. In a psychophysical experiment, we found that humans exploit this correlation. For a given binocular disparity, observers perceived more depth when the near surface's silhouette was convex rather than concave. We estimated the depth distributions observers used in making those judgments: they were similar to the natural-scene distributions. Our findings show that convexity should be reclassified as a metric depth cue. They also suggest that the dichotomy between metric and nonmetric depth cues is false and that the depth information provided many cues should be evaluated with respect to natural-scene statistics. Finally, the findings provide an explanation for why figure–ground cues modulate the responses of disparity-sensitive cells in visual cortex. PMID:20505093
Institutional and Cultural Perspectives on Home Birth in Israel
Meroz, Michal (Rosie); Gesser-Edelsburg, Anat
2015-01-01
ABSTRACT This study exposes doctors’ and midwives’ perceptions and misperceptions regarding home birth by examining their views on childbirth in general and on risk associated with home births in particular. It relies on an approach of risk communication and an anthropological framework. In a qualitative-constructive study, 19 in-depth interviews were conducted with hospital doctors, hospital midwives, home-birth midwives, and a home-birth obstetrician. Our findings reveal that hospital midwives and doctors suffer from lack of exposure to home births, leading to disagreement regarding norms and risk; it also revealed sexist or patriarchal worldviews. Recommendations include improving communication between home-birth midwives and hospital counterparts; increased exposure of hospital doctors to home birth, creating new protocols in collaboration with home-birth midwives; and establishing a national database of home births. PMID:26937159
Evaluation of microsurgical tasks with OCT-guided and/or robot-assisted ophthalmic forceps
Yu, Haoran; Shen, Jin-Hui; Shah, Rohan J.; Simaan, Nabil; Joos, Karen M.
2015-01-01
Real-time intraocular optical coherence tomography (OCT) visualization of tissues with surgical feedback can enhance retinal surgery. An intraocular 23-gauge B-mode forward-imaging co-planar OCT-forceps, coupling connectors and algorithms were developed to form a unique ophthalmic surgical robotic system. Approach to the surface of a phantom or goat retina by a manual or robotic-controlled forceps, with and without real-time OCT guidance, was performed. Efficiency of lifting phantom membranes was examined. Placing the co-planar OCT imaging probe internal to the surgical tool reduced instrument shadowing and permitted constant tracking. Robotic assistance together with real-time OCT feedback improved depth perception accuracy. The first-generation integrated OCT-forceps was capable of peeling membrane phantoms despite smooth tips. PMID:25780736
3D laptop for defense applications
NASA Astrophysics Data System (ADS)
Edmondson, Richard; Chenault, David
2012-06-01
Polaris Sensor Technologies has developed numerous 3D display systems using a US Army patented approach. These displays have been developed as prototypes for handheld controllers for robotic systems and closed hatch driving, and as part of a TALON robot upgrade for 3D vision, providing depth perception for the operator for improved manipulation and hazard avoidance. In this paper we discuss the prototype rugged 3D laptop computer and its applications to defense missions. The prototype 3D laptop combines full temporal and spatial resolution display with the rugged Amrel laptop computer. The display is viewed through protective passive polarized eyewear, and allows combined 2D and 3D content. Uses include robot tele-operation with live 3D video or synthetically rendered scenery, mission planning and rehearsal, enhanced 3D data interpretation, and simulation.
Introducing the depth transfer curve for 3D capture system characterization
NASA Astrophysics Data System (ADS)
Goma, Sergio R.; Atanassov, Kalin; Ramachandra, Vikas
2011-03-01
3D technology has recently made a transition from movie theaters to consumer electronic devices such as 3D cameras and camcorders. In addition to what 2D imaging conveys, 3D content also contains information regarding the scene depth. Scene depth is simulated through the strongest brain depth cue, namely retinal disparity. This can be achieved by capturing an image by horizontally separated cameras. Objects at different depths will be projected with different horizontal displacement on the left and right camera images. These images, when fed separately to either eye, leads to retinal disparity. Since the perception of depth is the single most important 3D imaging capability, an evaluation procedure is needed to quantify the depth capture characteristics. Evaluating depth capture characteristics subjectively is a very difficult task since the intended and/or unintended side effects from 3D image fusion (depth interpretation) by the brain are not immediately perceived by the observer, nor do such effects lend themselves easily to objective quantification. Objective evaluation of 3D camera depth characteristics is an important tool that can be used for "black box" characterization of 3D cameras. In this paper we propose a methodology to evaluate the 3D cameras' depth capture capabilities.
The right hemisphere in esthetic perception.
Bromberger, Bianca; Sternschein, Rebecca; Widick, Page; Smith, William; Chatterjee, Anjan
2011-01-01
Little about the neuropsychology of art perception and evaluation is known. Most neuropsychological approaches to art have focused on art production and have been anecdotal and qualitative. The field is in desperate need of quantitative methods if it is to advance. Here, we combine a quantitative approach to the assessment of art with modern voxel-lesion-symptom-mapping methods to determine brain-behavior relationships in art perception. We hypothesized that perception of different attributes of art are likely to be disrupted by damage to different regions of the brain. Twenty participants with right hemisphere damage were given the Assessment of Art Attributes, which is designed to quantify judgments of descriptive attributes of visual art. Each participant rated 24 paintings on 6 conceptual attributes (depictive accuracy, abstractness, emotion, symbolism, realism, and animacy) and 6 perceptual attributes (depth, color temperature, color saturation, balance, stroke, and simplicity) and their interest in and preference for these paintings. Deviation scores were obtained for each brain-damaged participant for each attribute based on correlations with group average ratings from 30 age-matched healthy participants. Right hemisphere damage affected participants' judgments of abstractness, accuracy, and stroke quality. Damage to areas within different parts of the frontal parietal and lateral temporal cortices produced deviation in judgments in four of six conceptual attributes (abstractness, symbolism, realism, and animacy). Of the formal attributes, only depth was affected by inferior prefrontal damage. No areas of brain damage were associated with deviations in interestingness or preference judgments. The perception of conceptual and formal attributes in artwork may in part dissociate from each other and from evaluative judgments. More generally, this approach demonstrates the feasibility of quantitative approaches to the neuropsychology of art.
Servin, Argentina E.; Muñoz, Fátima A.; Zúñiga, María Luisa
2015-01-01
Latinos living with HIV residing in the US-Mexico border region frequently seek care on both sides of the border. Given this fact, a border health perspective to understanding barriers to care is imperative to improve patient health outcomes. This qualitative study describes and compares experiences and perceptions of Mexican and US HIV care providers regarding barriers to HIV care access for Latino patients living in the US-Mexico border region. In 2010, we conducted in-depth qualitative interviews with HIV care providers in Tijuana (n = 10) and San Diego (n = 9). We identified important similarities and differences between Mexican and US healthcare provider perspectives on HIV care access and barriers to service utilisation. Similarities included the fact that HIV-positive Latino patients struggle with access to ART medication, mental health illness, substance abuse and HIV-related stigma. Differences included Mexican provider perceptions of medication shortages and US providers feeling that insurance gaps influenced medication access. Differences and similarities have important implications for cross-border efforts to coordinate health services for patients who seek care in both countries. PMID:24592920
Caregivers in China: Knowledge of Mild Cognitive Impairment
Dai, Baozhen; Mao, Zongfu; Mei, John; Levkoff, Sue; Wang, Huali; Pacheco, Misty; Wu, Bei
2013-01-01
This study aimed to examine the experience and knowledge of mild cognitive impairment (MCI) among Chinese family caregivers of individuals with MCI. The sample was recruited from memory clinics in Zhongnan Hospital in Wuhan, China. In-depth semi-structured interviews were used. Thirteen family members of individuals diagnosed with MCI participated in the study. Data analysis revealed three themes: 1) initial recognition of cognitive decline; 2) experience of the diagnosis of MCI; 3) perception of cognitive decline as a normal part of aging. While family members recognized the serious consequences of memory loss (e.g. getting lost), they would typically not take their family members to see a doctor until something specific triggered their access to the medical care system. The Chinese traditional perception of dementia as part of normal aging may serve to lessen the stigma of individuals with MCI, while the term “laonian chidai” which literally translates to “stupid, demented elderly” may exacerbate the stigma associated with individuals with MCI. It is suggested that family members’ worries may be relieved by improving their access to accurate knowledge of the disease, community-based and institutional care services, and culturally appropriately words are needed for MCI. PMID:23326541
Providers’ Perceptions of and Receptivity toward Evidence-Based HIV Prevention Interventions
Owczarzak, Jill; Dickson-Gomez, Julia
2014-01-01
Since 1999, the Centers for Disease Control have trained over 10,000 service providers from more than 5,000 agencies to implement evidence-based HIV prevention interventions through its Diffusion of Effective Behavioral Interventions (DEBI) program. Based on in-depth, semi-structured interviews with a convenience sample of 22 HIV prevention service providers from 8 agencies in Wisconsin who participated in DEBI training, this article explores providers’ motivations for attending DEBI training, perceptions of the utility and value of the DEBI program, and criticisms of the program. Providers indicated that they attended training as part of general skill-building efforts, as a way to improve services through the adoption of evidence-based interventions, and to better meet client needs. DEBI training participants were critical of the program's “top down” approach, perceived lack of fit between the DEBI and their target populations, and what they perceived as a lack of evidence that the interventions would work with their particular populations. These results suggest that in order for the DEBI program to be more widely accepted, the experiences and expertise of providers need to be more fully integrated into the processes of developing, disseminating, and adapting evidence-based HIV prevention interventions. PMID:21517660
Physicians' perceptions of mobile technology for enhancing asthma care for youth.
Schneider, Tali; Panzera, Anthony Dominic; Martinasek, Mary; McDermott, Robert; Couluris, Marisa; Lindenberger, James; Bryant, Carol
2016-06-01
This study assessed physicians' receptivity to using mobile technology as a strategy in patient care for adolescents with asthma. Understanding physicians' perceived barriers and benefits of integrating mobile technology in adolescents' asthma care and self-management is an initial step in enhancing overall patient and disease outcomes. We conducted in-depth interviews with second- and third-year pediatric residents and attending physicians who oversee pediatric residents in training (N = 27) at an academic medical center in the southeastern United States. We identified both benefits from and barriers to broader use of mobile technologies for improving asthma outcomes in adolescents. Resident physicians demonstrated greater readiness for integrating these technologies than did attending physicians. Prior to adoption of mobile technologies in the care of adolescent asthma patients, barriers to implementation should be understood. Prior to widespread adoption, such systems will need to be evaluated against traditional care for demonstration of patient outcomes that improve on the current situation. © The Author(s) 2014.
NASA Astrophysics Data System (ADS)
Leggett, Allison Gail Wilson
The No Child Left Behind (NCLB) Act of 2001 presented one of the most significant and comprehensive literacy reforms in many years (McDonnell, 2005; U.S. Department of Education, 2006). The era of school accountability and standards based reform has brought many challenges and changes to public schools. Increasingly, public officials and educational administrators are asked to use standards based assessments to make high-stakes decisions, such as whether a student will move on to the next grade level or receive a diploma (American Psychological Association, 2005). It is important to understand any shifts in teachers' perceptions and to identify the changes teachers are making as they implement standards-based reform. This mixed-methods study was designed to assess teachers' perceptions of changes related to standards-based reform as supported by Fullan's (2001) change theory and transformational leadership theory. Survey questions sought to identify teacher perceptions of changes in curriculum, instruction and daily practice as schools documented and incorporated standards-based reform and began focusing on preparing students for the California Standards Test in Science (CSTS). Using descriptive statistical analysis and in-depth interviews, results show favorable insight towards standards-based reform. The survey was distributed to 30 middle school science teachers from 10 low-performing schools in Los Angeles, California. Results were analyzed using Spearman rank-ordered correlations. Interviews were conducted on middle school teachers represented by each grade level. Teachers who receive more support from administrators have more positive attitudes toward all aspects of SBR and the CSTS as measured in this study. No school should overlook the potential of a supportive administration in its effort to improve school programs.
Presentations of Shape in Object Recognition and Long-Term Visual Memory
1994-04-05
theory of human image understanding . Psychological Review, 94, 115-147. Biederman, I., & Gerhardstein, P. C. (1993). Recognizing depth-rotated...Kybemetik. Submitted to Journal of Experimental Psychology: Human Perception and Performance. REFERENCES Biederman, I. (1987). Recognition-by-components: A
Size cues and the adjacency principle.
DOT National Transportation Integrated Search
1963-11-01
The purpose of the present study was to apply the adjacency principle to the perception of relative depth from size cues. In agreement with the adjacency principle, it was found that the size cue between adjacent objects was more effective than the s...
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.
Schofield, Casey A; Weis, Henry; Ponzini, Gabriella; McHugh, R Kathryn
2017-12-01
The current study aimed to determine whether brief exposure to a webpage about cognitive-behavioral therapy (CBT) for the anxiety disorders improved knowledge and perceptions of this treatment. Further, this study tested whether participants were uniquely compelled by CBT if the mechanism of change cited neurological processes. Participants (N = 389) recruited online viewed a webpage screenshot that described CBT for anxiety. Participants were randomized to view a version of the webpage which either described the mechanism of change as: 1) psychological, 2) neurological, 3) combination of neurological and psychological, or 4) no mechanism described. Participants completed measures of knowledge and perception of CBT before and after viewing the webpage. Credibility ratings and symptoms were assessed after viewing the webpage. Knowledge of CBT was limited and perceptions were largely neutral to somewhat positive at baseline. Both knowledge and perceptions of CBT meaningfully improved after viewing the webpage. Mechanism of change did not impact perceptions of CBT or its credibility, though in the neurological and combination conditions there was less improvement in knowledge than in the psychological or control conditions. Greater symptoms of anxiety were associated with slightly less improvement in knowledge and perceptions. The study did not include long-term follow up, so the durability of the effects is unknown. Further, sample homogeneity undermines broad generalizability. There is significant room and capacity to improve lay-people's knowledge and perceptions of CBT. Neurological explanations did not appear to uniquely promote the perception of CBT or its credibility. Copyright © 2017. Published by Elsevier Ltd.
Perception of Child Weight and Feeding Styles in Parents of Chinese-American Preschoolers.
Chang, Lucy Y; Mendelsohn, Alan L; Fierman, Arthur H; Au, Loretta Y; Messito, Mary Jo
2017-04-01
Parent perception of weight and feeding styles are associated with obesity in other racial groups but have not been explored in-depth in Chinese-American preschoolers. Cross-sectional survey of 253 Chinese-American parents with preschoolers was performed in a community clinic. Regression analysis was used to assess relationships between parental perception of weight and feeding styles. Parent under-perception of weight was common but more likely in boys than girls (χ 2 = 4.91, p = 0.03). Pressuring was also greater in boys [adjusted mean difference (95% CI) 0.24 (0.004, 0.49)]. In girls, pressuring was lower for children perceived as overweight [adjusted mean difference in CFQ scores -0.75 (-1.27, -0.23)]; in boys, pressuring was high regardless of perceived child weight. Weight perceptions and feeding styles related to childhood obesity in other groups were identified in Chinese-American families. Parent under-perception of child weight and pressure to eat were more common in boys. These factors should be addressed in Chinese-American preschooler obesity prevention programs.
Valenta, Sabine; De Geest, Sabina; Fierz, Katharina; Beckmann, Sonja; Halter, Jörg; Schanz, Urs; Nair, Gayathri; Kirsch, Monika
2017-04-01
To give a first description of the perception of late effects among long-term survivors after Allogeneic Haematopoietic Stem Cell Transplantation (HSCT) and to validate the German Brief Illness Perception Questionnaire (BIPQ). This is a secondary analysis of data from the cross-sectional, mixed-method PROVIVO study, which included 376 survivors from two Swiss HSCT-centres. First, we analysed the sample characteristics and the distribution for each BIPQ item. Secondly, we tested three validity types following the American Educational Research Association (AERA)Standards: content validity indices (CVIs) were assessed based on an expert survey (n = 9). A confirmatory factor analysis (CFA) explored the internal structure, and correlations tested the validity in relations to other variables including data from the Hospital Anxiety and Depression Scale (HADS), the number and burden of late effects and clinical variables. In total, 319 HSCT recipients returned completed BIPQs. For this sample, the most feared threat for post-transplant life was long lasting late effects (median = 8/10). The expert-survey revealed an overall acceptable CVI (0.82), three items-on personal control, treatment control and causal representation-yielded low CVIs (<.78). The CFA confirmed that the BIPQ fits the underlying construct, the Common-Sense Model (CSM) (χ 2 (df) = 956.321, p = 0.00). The HADS-scores correlated strongly with the item emotional representation (r = 0.648; r = 0.656). According to its overall content validity, the German BIPQ is a promising instrument to gain deeper insights into patients' perceptions of HSCT late effects. However, as three items revealed potential problems, improvements and adaptions in translation are therefore required. Following these revisions, validity evidence should be re-examined through an in-depth patient survey. Copyright © 2017 Elsevier Ltd. All rights reserved.
Climate Change Perceptions of NY State Farmers: The Role of Risk Perceptions and Adaptive Capacity.
Takahashi, Bruno; Burnham, Morey; Terracina-Hartman, Carol; Sopchak, Amanda R; Selfa, Theresa
2016-12-01
Climate change is expected to severely impact agricultural practices in many important food-producing regions, including the Northeast United States. Changing climate conditions, such as increases in the amount of rainfall, will require farmers to adapt. Yet, little is known with regard to farmers' perceptions and understandings about climate change, especially in the industrialized country context. This paper aims at overcoming this research limitation, as well as determining the existing contextual, cognitive, and psychological barriers that can prevent adoption of sustainable practices of farmers in New York State. The study is framed within the adaptive capacity and risk perception literature, and is based on a qualitative analysis of in-depth interviews with farmers in 21 farms in two counties in Central New York. The results reveal diverging views about the long-term consequences of climate change. Results also reveal that past experience remains as the most important source of information that influences beliefs and perceptions about climate change, confirming previous research.
Climate Change Perceptions of NY State Farmers: The Role of Risk Perceptions and Adaptive Capacity
NASA Astrophysics Data System (ADS)
Takahashi, Bruno; Burnham, Morey; Terracina-Hartman, Carol; Sopchak, Amanda R.; Selfa, Theresa
2016-12-01
Climate change is expected to severely impact agricultural practices in many important food-producing regions, including the Northeast United States. Changing climate conditions, such as increases in the amount of rainfall, will require farmers to adapt. Yet, little is known with regard to farmers' perceptions and understandings about climate change, especially in the industrialized country context. This paper aims at overcoming this research limitation, as well as determining the existing contextual, cognitive, and psychological barriers that can prevent adoption of sustainable practices of farmers in New York State. The study is framed within the adaptive capacity and risk perception literature, and is based on a qualitative analysis of in-depth interviews with farmers in 21 farms in two counties in Central New York. The results reveal diverging views about the long-term consequences of climate change. Results also reveal that past experience remains as the most important source of information that influences beliefs and perceptions about climate change, confirming previous research.
Networking activities and perceptions of HIV risk among male migrant market vendors in China.
Wang, Wenqing; Muessig, Kathryn E; Li, Mingqiang; Zhang, Ying-Xia; Zhang, Yingxia
2014-02-01
HIV research among internal migrants in China has not fully explored the contexts and perceptions of "risk". In 2011, urban markets in Liuzhou, China were mapped, and sixty male vendors, age 22-56, were selected for in-depth interviews on migration, social and family life, and perceptions and practices of sexual risk behavior. Participants were evenly divided among higher income shop and small stall vendors. All men were sexually active. Only the shop vendors reported non-marital sexual partners, including concurrent partners (n = 15), commercial partners (n = 10), and other sexual relationships (n = 11). Shop vendors engaged in networking activities that facilitated commercial and non-commercial high-risk sex. Perceptions of HIV risk from commercial sex led some men to doubt the protective ability of condoms and rely on local (unproven) self-protection techniques. Networking activities played a role in high-risk sex and shaping migrants' risk perceptions and health practices. The networks created through these processes could also be used to facilitate health promotion activities.
Ernecoff, Natalie C; Witteman, Holly O; Chon, Kristen; Chen, Yanquan Iris; Buddadhumaruk, Praewpannarai; Chiarchiaro, Jared; Shotsberger, Kaitlin J; Shields, Anne-Marie; Myers, Brad A; Hough, Catherine L; Carson, Shannon S; Lo, Bernard; Matthay, Michael A; Anderson, Wendy G; Peterson, Michael W; Steingrub, Jay S; Arnold, Robert M; White, Douglas B
2016-06-01
Although barriers to shared decision making in intensive care units are well documented, there are currently no easily scaled interventions to overcome these problems. We sought to assess stakeholders' perceptions of the acceptability, usefulness, and design suggestions for a tablet-based tool to support communication and shared decision making in ICUs. We conducted in-depth semi-structured interviews with 58 key stakeholders (30 surrogates and 28 ICU care providers). Interviews explored stakeholders' perceptions about the acceptability of a tablet-based tool to support communication and shared decision making, including the usefulness of modules focused on orienting families to the ICU, educating them about the surrogate's role, completing a question prompt list, eliciting patient values, educating about treatment options, eliciting perceptions about prognosis, and providing psychosocial support resources. The interviewer also elicited stakeholders' design suggestions for such a tool. We used constant comparative methods to identify key themes that arose during the interviews. Overall, 95% (55/58) of participants perceived the proposed tool to be acceptable, with 98% (57/58) of interviewees finding six or more of the seven content domains acceptable. Stakeholders identified several potential benefits of the tool including that it would help families prepare for the surrogate role and for family meetings as well as give surrogates time and a framework to think about the patient's values and treatment options. Key design suggestions included: conceptualize the tool as a supplement to rather than a substitute for surrogate-clinician communication; make the tool flexible with respect to how, where, and when surrogates can access the tool; incorporate interactive exercises; use video and narration to minimize the cognitive load of the intervention; and build an extremely simple user interface to maximize usefulness for individuals with low computer literacy. There is broad support among stakeholders for the use of a tablet-based tool to improve communication and shared decision making in ICUs. Eliciting the perspectives of key stakeholders early in the design process yielded important insights to create a tool tailored to the needs of surrogates and care providers in ICUs. Copyright © 2016 Elsevier Inc. All rights reserved.
Perceptions of teaching and learning automata theory in a college-level computer science course
NASA Astrophysics Data System (ADS)
Weidmann, Phoebe Kay
This dissertation identifies and describes student and instructor perceptions that contribute to effective teaching and learning of Automata Theory in a competitive college-level Computer Science program. Effective teaching is the ability to create an appropriate learning environment in order to provide effective learning. We define effective learning as the ability of a student to meet instructor set learning objectives, demonstrating this by passing the course, while reporting a good learning experience. We conducted our investigation through a detailed qualitative case study of two sections (118 students) of Automata Theory (CS 341) at The University of Texas at Austin taught by Dr. Lily Quilt. Because Automata Theory has a fixed curriculum in the sense that many curricula and textbooks agree on what Automata Theory contains, differences being depth and amount of material to cover in a single course, a case study would allow for generalizable findings. Automata Theory is especially problematic in a Computer Science curriculum since students are not experienced in abstract thinking before taking this course, fail to understand the relevance of the theory, and prefer classes with more concrete activities such as programming. This creates a special challenge for any instructor of Automata Theory as motivation becomes critical for student learning. Through the use of student surveys, instructor interviews, classroom observation, material and course grade analysis we sought to understand what students perceived, what instructors expected of students, and how those perceptions played out in the classroom in terms of structure and instruction. Our goal was to create suggestions that would lead to a better designed course and thus a higher student success rate in Automata Theory. We created a unique theoretical basis, pedagogical positivism, on which to study college-level courses. Pedagogical positivism states that through examining instructor and student perceptions of teaching and learning, improvements to a course are possible. These improvements can eventually develop a "best practice" instructional environment. This view is not possible under a strictly constructivist learning theory as there is no way to teach a group of individuals in a "best" way. Using this theoretical basis, we examined the gathered data from CS 341. (Abstract shortened by UMI.)
Final year MBBS students' perception for observed structured clinical examination.
Siddiqui, Faisal Ghani
2013-01-01
To determine perceptions of final year students about observed structured clinical examination (OSCE) and to determine its acceptance among these students. Sequential mixed method design using survey questionnair and in-depth interviews. The study constituted a one-time survey and in-depth interviews conducted over a period of three consecutive days during final year MBBS annual examination at OSCE centre, from April 04, 2010 to April 06, 2010. Three hundred and fifty final year MBBS students, selected through non-probability convenience sampling, were asked to fill the 12-item questionnaire. Three hundred and thirty one students returned the forms. In-depth, structured interviews with 22 students, selected by non-probability purposive sampling, were conducted. The interviews were tape recorded for subsequent transcription. The statistical analysis was done using SPSS 17. The qualitative data was analyzed through content analysis techniques. Three hundred and thirty one final year MBBS students (50.6% females) filled the questionnaire (response rate 94.6%). Fifty three percent respondents agreed that the OSCE tasks were taught during clinical rotations. The experience was stressful for 67.9% respondents. Inadequate prior guidelines, inadequate time for stations, newness of the assessment format and vague instructions were the main causes for stress. Over 70% of the students felt that OSCE helped them identify areas of weakness in their practical and clinical skills; 56.5% felt that the stations dealt with practical skills. Seventy nine percent students were happy with the attitude of the examiners while 19% students felt that the facilitators were uncooperative; failure of the examiners to observe the students during performance of the tasks was the major cause for dissatisfaction. Nearly thirty percent (29.9%) respondent felt that the stations were difficult to understand. Over forty nine percent (49.7%) complained that adequate guidelines were not given prior to the examination. Overall, 67% students were satisfied with this new method of assessment. The overall acceptance of the students for OSCE was low. Reforms such as redesigning of curriculum and learning objectives, training the faculty in conduct of OSCE, involving more external examiners and establishment of a skill's lab would help improve this assessment tool.
Farista, Sana; Koppolu, Pradeep; Baroudi, Kusai; Uppada, Udaykiran; Mishra, Ashank; Savarimath, Abhishek; Lingam, Amara Swapna
2016-01-01
Introduction Inadequate vestibular depth results in poor plaque control owing to an insufficient width of keratinized gingiva. Vestibuloplasty provides the necessary vestibular depth and can be performed either with a scalpel, electrocautery or lasers. Aim To evaluate the patient perceptions related to pain and discomfort on the 1st, 3rd and the 7th day post vestibuloplasty and also assess the healing outcomes related to the treatment of inadequate vestibular depth either with the diode laser or the scalpel. Materials and Methods Twenty patients who had inadequate vestibular depth and required vestibuloplasty were assigned randomly to undergo the procedure either with the scalpel or the laser. The data obtained was analysed for intergroup comparison with an independent paired t-test and intragroup comparison was determined by a paired t-test. Results Intragroup comparison within the laser group for VAS scores of pain and discomfort within all the reported days exhibited a significant difference (p<0.05). Inter group comparison revealed that the patients in the laser group had lower VAS cores for pain and discomfort compared to the scalpel group (p<0.05). Analysis of the three pointer scale for healing revealed that the patients in the laser group exhibited better healing outcomes on the 1st, 3rd and the 7th day compared to the scalpel group. Conclusion Observations from the study highlight the opinion that laser can be a safe and effective alternative to traditional vestibuloplasty performed with the scalpel. PMID:27437370
Dennis, Amanda; Blanchard, Kelly
2013-01-01
Objective To evaluate the implementation of state Medicaid abortion policies and the impact of these policies on abortion clients and abortion providers. Data Source From 2007 to 2010, in-depth interviews were conducted with representatives of 70 abortion-providing facilities in 15 states. Study Design In-depth interviews focused on abortion providers' perceptions regarding Medicaid and their experiences working with Medicaid and securing reimbursement in cases that should receive federal funding: rape, incest, and life endangerment. Data Extraction Data were transcribed verbatim before being coded. Principal Findings In two study states, abortion providers reported that 97 percent of submitted claims for qualifying cases were funded. Success receiving reimbursement was attributed to streamlined electronic billing procedures, timely claims processing, and responsive Medicaid staff. Abortion providers in the other 13 states reported reimbursement for 36 percent of qualifying cases. Providers reported difficulties obtaining reimbursement due to unclear rejections of qualifying claims, complex billing procedures, lack of knowledgeable Medicaid staff with whom billing problems could be discussed, and low and slow reimbursement rates. Conclusions Poor state-level implementation of Medicaid coverage of abortion policies creates barriers for women seeking abortion. Efforts to ensure policies are implemented appropriately would improve women's health. PMID:22742741
Dennis, Amanda; Blanchard, Kelly
2013-02-01
To evaluate the implementation of state Medicaid abortion policies and the impact of these policies on abortion clients and abortion providers. From 2007 to 2010, in-depth interviews were conducted with representatives of 70 abortion-providing facilities in 15 states. In-depth interviews focused on abortion providers' perceptions regarding Medicaid and their experiences working with Medicaid and securing reimbursement in cases that should receive federal funding: rape, incest, and life endangerment. Data were transcribed verbatim before being coded. In two study states, abortion providers reported that 97 percent of submitted claims for qualifying cases were funded. Success receiving reimbursement was attributed to streamlined electronic billing procedures, timely claims processing, and responsive Medicaid staff. Abortion providers in the other 13 states reported reimbursement for 36 percent of qualifying cases. Providers reported difficulties obtaining reimbursement due to unclear rejections of qualifying claims, complex billing procedures, lack of knowledgeable Medicaid staff with whom billing problems could be discussed, and low and slow reimbursement rates. Poor state-level implementation of Medicaid coverage of abortion policies creates barriers for women seeking abortion. Efforts to ensure policies are implemented appropriately would improve women's health. © Health Research and Educational Trust.
Sakata, H; Taira, M; Kusunoki, M; Murata, A; Tanaka, Y
1997-08-01
Recent neurophysiological studies in alert monkeys have revealed that the parietal association cortex plays a crucial role in depth perception and visually guided hand movement. The following five classes of parietal neurons covering various aspects of these functions have been identified: (1) depth-selective visual-fixation (VF) neurons of the inferior parietal lobule (IPL), representing egocentric distance; (2) depth-movement sensitive (DMS) neurons of V5A and the ventral intraparietal (VIP) area representing direction of linear movement in 3-D space; (3) depth-rotation-sensitive (RS) neurons of V5A and the posterior parietal (PP) area representing direction of rotary movement in space; (4) visually responsive manipulation-related neurons (visual-dominant or visual-and-motor type) of the anterior intraparietal (AIP) area, representing 3-D shape or orientation (or both) of objects for manipulation; and (5) axis-orientation-selective (AOS) and surface-orientation-selective (SOS) neurons in the caudal intraparietal sulcus (cIPS) sensitive to binocular disparity and representing the 3-D orientation of the longitudinal axes and flat surfaces, respectively. Some AOS and SOS neurons are selective in both orientation and shape. Thus the dorsal visual pathway is divided into at least two subsystems, V5A, PP and VIP areas for motion vision and V6, LIP and cIPS areas for coding position and 3-D features. The cIPS sends the signals of 3-D features of objects to the AIP area, which is reciprocally connected to the ventral premotor (F5) area and plays an essential role in matching hand orientation and shaping with 3-D objects for manipulation.
Chiang, Kuei-Feng; Wang, Hsiu-Hung; Chien, I-Kuang; Liou, Jhao-Kun; Hung, Chung-Lieh; Huang, Chien-Min; Yang, Feng-Yueh
2015-04-01
Telecare has not only brought down medical expenses, but has also become an important tool to address healthcare needs. In recent years, the Taiwanese government has been concerned about this healthcare issue. However, only a few hospitals provide telecare. This study aims at investigating the barriers that healthcare providers face while implementing home telecare in Taiwan. A qualitative research design was employed in this study, with semi-structured in-depth interviews. The sample was obtained from five hospitals, including three medical centers and two regional hospitals. A total of 31 healthcare providers were interviewed, including case managers (n=11), administrators (n=7), physicians (n=7), and nurses (n=6). The results were summarized into five themes, including: (1) unsuitable laws and vague policies, (2) the policy implementation fails to meet public needs, (3) lack of organizational support, (4) lack of quality and convenience of the system, and (5) inadequate public perception and attitudes. Obstacles in policy and regulations are the most fundamental difficulties for telecare implementation, therefore the government should provide a clear direction by planning policies, legislate appropriate regulations, and incorporate telecare into the scope of medical insurance, in order to improve the environment and stimulate the telecare service market. In order to improve the success rate of telecare, administrators should be able to identify an appropriate cost-benefit model to build a humane system to satisfy public needs and to provide staff with resources and support. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Bridges, John Fp; Gallego, Gisselle; Blauvelt, Barri M
2011-07-28
Liver cancer is the fifth most common cancer in men and the seventh for women. Usually because of late diagnosis, the prognosis for liver cancer remains poor, resulting in liver cancer being the third most common cause of death from cancer. While some countries have treatment guidelines, little is known or understood about the strategies needed for liver cancer control internationally. To explore leading liver cancer clinician's perceptions of the current public policy needs to control liver cancer internationally. Key informant interviews were conducted with a range of liver cancer clinicians involved in policy in eleven countries. Interviews were digitally recorded, transcribed verbatim, translated (where necessary), de-identified and analyzed by two researchers using a constant comparative method. Twenty in-depth semi-structured interviews were conducted in: Australia, China, France, Germany, Italy, Japan, Spain, South Korea, Taiwan, Turkey and the United States. Nine themes were identified and cluster into three groups: 1) Promoting prevention via early risk assessment, focusing on viral hepatitis and other lifestyle factors; 2) Increasing political, public and medical community awareness; and 3) Improving funding for screening, liver cancer surveillance and treatment. This study is an important step towards developing an evidence-based approach to assessing preparedness for implementing comprehensive liver cancer control strategies. Evaluation mechanisms to assess countries' performance on the needs described are needed. Future research will concentrate of understanding how these needs vary across countries and the optimal strategies to improve the diagnosis and prognosis of patients with liver cancer internationally.
Problems in depth perception : equidistance judgments in the vicinity of a binocular illusion.
DOT National Transportation Integrated Search
1966-07-01
Judgments of the size and distance of objects are sometimes made in aircraft under background-viewing conditions that may themselves create false sensory impressions (illusions). In this study, the effects of a background illusion on judgments of the...
The equidistance tendency and its consequences : problems in depth perception.
DOT National Transportation Integrated Search
1965-04-01
The equidistance tendency is the tendency for objects or other inhomogeneities in the field-of-view to appear at the same distance as each other with the strength of this tendency being inversely related to directional separation. The evidence for th...
NASA Astrophysics Data System (ADS)
Ogawa, Masahiko; Shidoji, Kazunori
2011-03-01
High-resolution stereoscopic images are effective for use in virtual reality and teleoperation systems. However, the higher the image resolution, the higher is the cost of computer processing and communication. To reduce this cost, numerous earlier studies have suggested the use of multi-resolution images, which have high resolution in region of interests and low resolution in other areas. However, observers can perceive unpleasant sensations and incorrect depth because they can see low-resolution areas in their field of vision. In this study, we conducted an experiment to research the relationship between the viewing field and the perception of image resolution, and determined respective thresholds of image-resolution perception for various positions of the viewing field. The results showed that participants could not distinguish between the high-resolution stimulus and the decreased stimulus, 63 ppi, at positions more than 8 deg outside the gaze point. Moreover, with positions shifted a further 11 and 13 deg from the gaze point, participants could not distinguish between the high-resolution stimulus and the decreased stimuli whose resolution densities were 42 and 25 ppi. Hence, we will propose the composition of multi-resolution images in which observers do not perceive unpleasant sensations and incorrect depth with data reduction (compression).
College student perceptions of science teachers and the effect on science teaching as a career path
NASA Astrophysics Data System (ADS)
Cost, Michael George
2000-10-01
Past research documented that student perceptions of scientists constituted a stereotypical image that had a negative effect on the students' attitudes towards science and resulted in low numbers of students studying to become scientists and engineers in college. The present study paralleled the research on student perceptions of scientists to investigate to what extent student perceptions of science teachers affect their willingness to consider science teaching as a career. This was accomplished by surveying 91 college students and 25 science teachers at the beginning, middle, and end of the collegiate career path of becoming a science teacher. Each survey contained quantitative data utilizing seven-point semantic differential scales and written open response questions. In-depth interviews with two members of each level were conducted to supplement the survey data. The study found that college students begin college with a positive perception of teaching as a career and highly rank teachers, especially science teachers, as having a positive influence on their career path. The qualities of job enjoyment, job stability, and helping others that are characteristic of teaching were also found to be of high importance. Perceptions of the personal, social, professional, and career qualities of a science teacher were found to differ from a scientist. While both science teachers and scientists were found to be responsible, persistent, and productive, science teachers were perceived as being a distinct career possessing qualities that make them more personable, sociable, and wise than scientists. Some gender differences were detected but there was no evidence of gender bias affecting students choosing a career path to science teaching. Science teachers were perceived to be very supportive of females pursuing scientific career paths. The study also found evidence that some introductory level college students steer away from science teaching because of low salary, the lack of promotion, and the efforts of influential people including science teachers. The study calls for departments of science education to take a more active role in the recruitment of new science teachers and the improvement of undergraduate science education.
Self-perception of voice in transgender persons during cross-sex hormone therapy.
Bultynck, Charlotte; Pas, Charlotte; Defreyne, Justine; Cosyns, Marjan; den Heijer, Martin; T'Sjoen, Guy
2017-12-01
Self-perception of voice has a significant psychosocial impact on transgender persons. Research about the evolution of self-perception of voice during cross-sex hormone therapy (CSHT) is lacking. The aim of this study was to examine if self-perception of voice changes during CSHT, and if a change of serum testosterone levels as a result of CSHT can predict a change of self-perception of voice. Prospective longitudinal study. The Transsexual Voice Questionnaire (TVQ), consisting of three factors-anxiety and avoidance (AA), gender identity (GI), and voice quality (VQ)-was used. Transgender persons completed the TVQ at baseline (80 trans men and 103 trans women), after 3 and 12 months of CSHT follow-up. Trans men: From 0 to 3 months, 0 to 12 months, and 3 to 2 months of CSHT, the AA and GI scores improved. From 0 to 3 months of CSHT, the increasing testosterone level was predictive for the improvements of AA and GI scores. Trans women: From 0 to 3 months, the GI score improved. From 0 to 12 months, the AA, GI, and VQ scores improved. Improvements of self-perception of voice could not be predicted by changing serum testosterone levels. During CSHT, self-perception of voice improves in both trans men and trans women. In trans men only, the improving self-perception of voice during the first 3 months can be attributed to the CSHT. For trans women, this study supports that testosterone has acted irreversibly virializing to the voice before CSHT, if they already went through male puberty. 4. Laryngoscope, 127:2796-2804, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.
Fransen, Mirjam P; Beune, Erik J A J; Baim-Lance, Abigail M; Bruessing, Raynold C; Essink-Bot, Marie-Louise
2015-05-01
The aim of the present study was to explore perceptions and strategies of health care providers regarding diabetes self-management support for patients with low health literacy (LHL), and to compare their self-management support with the needs of patients with LHL and type 2 diabetes. This study serves as a problem analysis for systematic intervention development to improve diabetes self-management among patients with LHL. This qualitative study used in-depth interviews with general practitioners (n = 4), nurse practitioners (n = 5), and patients with LHL (n = 31). The results of the interviews with health care providers guided the patient interviews. In addition, we observed 10 general practice consultations. Providers described patients with LHL as uninvolved and less motivated patients who do not understand self-management. Their main strategy to improve self-management was to provide standard information on a repeated basis. Patients with LHL seemed to have a different view of diabetes self-management than their providers. Most demonstrated a low awareness of what self-management involves, but did not express needing more information. They reported several practical barriers to self-management, although they seemed reluctant to use the information provided to overcome them. Providing and repeating information does not fit the needs of patients with LHL regarding diabetes self-management support. Health care providers do not seem to have the insight or the tools to systematically support diabetes self-management in this group. Systematic intervention development with a focus on skills-based approaches rather than cognition development may improve diabetes self-management support of patients with LHL. © 2014 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.
Shaw, Bryan; Amouzou, Agbessi; Miller, Nathan P; Bryce, Jennifer; Surkan, Pamela J
2017-03-09
Ethiopia has experienced rapid improvements in its healthcare infrastructure, such as through the recent scale up of integrated community case management (iCCM) delivered by community-based health extension workers (HEWs) targeting children under the age of five. Despite notable improvements in child outcomes, the use of HEWs delivering iCCM remains very low. The aim of our study was to explain this phenomenon by examining care-seeking practices and treatment for sick children in two rural districts in the Oromia Region of Ethiopia. Using qualitative methods, we explored perceptions of child illness, influences on decision-making processes occurring over the course of a child's illness and caregiver perceptions of available community-based sources of child illness care. Sixteen focus group discussions (FGDs) and 40 in-depth interviews (IDIs) were held with mothers of children under age five. For additional perspective, 16 IDIs were conducted fathers and 22 IDIs with health extension workers and community health volunteers. Caregivers often described the act of care-seeking for a sick child as a time of considerable uncertainty. In particular, mothers of sick children described the cultural, social and community-based resources available to minimize this uncertainty as well as constraints and strategies for accessing these resources in order to receive treatment for a sick child. The level of trust and familiarity were the most common dynamics noted as influencing care-seeking strategies; trust in biomedical and government providers was often low. Overall, our research highlights the multiple and dynamic influences on care-seeking for sick children in rural Ethiopia. An understanding of these influences is critical for the success of existing and future health interventions and continued improvement of child health in Ethiopia.
Sharma, Bharati; Ramani, K.V.; Mavalankar, Dileep; Kanguru, Lovney; Hussein, Julia
2015-01-01
Background Infections acquired during childbirth are a common cause of maternal and perinatal mortality and morbidity. Changing provider behaviour and organisational settings within the health system is key to reducing the spread of infection. Objective To explore the opinions of health personnel on health system factors related to infection control and their perceptions of change in a sample of hospital maternity units. Design An organisational change process called ‘appreciative inquiry’ (AI) was introduced in three maternity units of hospitals in Gujarat, India. AI is a change process that builds on recognition of positive actions, behaviours, and attitudes. In-depth interviews were conducted with health personnel to elicit information on the environment within which they work, including physical and organisational factors, motivation, awareness, practices, perceptions of their role, and other health system factors related to infection control activities. Data were obtained from three hospitals which implemented AI and another three not involved in the intervention. Results Challenges which emerged included management processes (e.g. decision-making and problem-solving modalities), human resource shortages, and physical infrastructure (e.g. space, water, and electricity supplies). AI was perceived as having a positive influence on infection control practices. Respondents also said that management processes improved although some hospitals had already undergone an accreditation process which could have influenced the changes described. Participants reported that team relationships had been strengthened due to AI. Conclusion Technical knowledge is often emphasised in health care settings and less attention is paid to factors such as team relationships, leadership, and problem solving. AI can contribute to improving infection control by catalysing and creating forums for team building, shared decision making and problem solving in an enabling environment. PMID:26119249
Sharma, Bharati; Ramani, K V; Mavalankar, Dileep; Kanguru, Lovney; Hussein, Julia
2015-01-01
Infections acquired during childbirth are a common cause of maternal and perinatal mortality and morbidity. Changing provider behaviour and organisational settings within the health system is key to reducing the spread of infection. To explore the opinions of health personnel on health system factors related to infection control and their perceptions of change in a sample of hospital maternity units. An organisational change process called 'appreciative inquiry' (AI) was introduced in three maternity units of hospitals in Gujarat, India. AI is a change process that builds on recognition of positive actions, behaviours, and attitudes. In-depth interviews were conducted with health personnel to elicit information on the environment within which they work, including physical and organisational factors, motivation, awareness, practices, perceptions of their role, and other health system factors related to infection control activities. Data were obtained from three hospitals which implemented AI and another three not involved in the intervention. Challenges which emerged included management processes (e.g. decision-making and problem-solving modalities), human resource shortages, and physical infrastructure (e.g. space, water, and electricity supplies). AI was perceived as having a positive influence on infection control practices. Respondents also said that management processes improved although some hospitals had already undergone an accreditation process which could have influenced the changes described. Participants reported that team relationships had been strengthened due to AI. Technical knowledge is often emphasised in health care settings and less attention is paid to factors such as team relationships, leadership, and problem solving. AI can contribute to improving infection control by catalysing and creating forums for team building, shared decision making and problem solving in an enabling environment.
Description of Success: A Four-Teacher Instructional Model.
ERIC Educational Resources Information Center
Reed, Dianne
This study described a four-teacher instructional model in operation at an elementary school, noting the perceptions of fourth grade students, parents, and teachers regarding the model. The model encompassed teaming, block scheduling, departmentalization of subjects, integrated/interdisciplinary instruction, and in-depth instruction in each…
PSYCHOSOCIAL PHENOMENA AND BUILDING DESIGN.
ERIC Educational Resources Information Center
IZUMI, KIYOSHI
THE DEPTH OF PSYCHOSOCIAL CONSIDERATION VARIES WITH ARCHITECTURAL FUNCTION. THESE FACTORS INCREASE AS A BUILDING USAGE BECOMES MORE ANTHROPOPHILIC. SITUATIONS RELATING TO AMBIGUOUS DESIGN MUST BE ELIMINATED IN BUILDING DESIGN. PROBLEMS INVOLVING VISUAL PERCEPTION SUCH AS (1) GLASS DOORS, (2) APPARENT INSECURITY OF STRUCTURE, (3) AMBIGUOUS SYMBOLIC…
Parent Empowerment and Teacher Professionalism: Teachers' Perspective
ERIC Educational Resources Information Center
Addi-Raccah, Audrey; Arviv-Elyashiv, Rinate
2008-01-01
School decentralization, which has reshaped power relations in the educational system, has empowered teachers and parents. Taking Abbott's approach to professions, the authors examine teachers' perceptions of the implications of parents' empowerment for teacher--parent relations. In-depth interviews with homeroom teachers in affluent urban…
Binocular Perception of 2D Lateral Motion and Guidance of Coordinated Motor Behavior.
Fath, Aaron J; Snapp-Childs, Winona; Kountouriotis, Georgios K; Bingham, Geoffrey P
2016-04-01
Zannoli, Cass, Alais, and Mamassian (2012) found greater audiovisual lag between a tone and disparity-defined stimuli moving laterally (90-170 ms) than for disparity-defined stimuli moving in depth or luminance-defined stimuli moving laterally or in depth (50-60 ms). We tested if this increased lag presents an impediment to visually guided coordination with laterally moving objects. Participants used a joystick to move a virtual object in several constant relative phases with a laterally oscillating stimulus. Both the participant-controlled object and the target object were presented using a disparity-defined display that yielded information through changes in disparity over time (CDOT) or using a luminance-defined display that additionally provided information through monocular motion and interocular velocity differences (IOVD). Performance was comparable for both disparity-defined and luminance-defined displays in all relative phases. This suggests that, despite lag, perception of lateral motion through CDOT is generally sufficient to guide coordinated motor behavior.
NASA Astrophysics Data System (ADS)
Wixson, Steve E.
1990-07-01
Transparent Volume Imaging began with the stereo xray in 1895 and ended for most investigators when radiation safety concerns eliminated the second view. Today, similiar images can be generated by the computer without safety hazards providing improved perception and new means of image quantification. A volumetric workstation is under development based on an operational prototype. The workstation consists of multiple symbolic and numeric processors, binocular stereo color display generator with large image memory and liquid crystal shutter, voice input and output, a 3D pointer that uses projection lenses so that structures in 3 space can be touched directly, 3D hard copy using vectograph and lenticular printing, and presentation facilities using stereo 35mm slide and stereo video tape projection. Volumetric software includes a volume window manager, Mayo Clinic's Analyze program and our Digital Stereo Microscope (DSM) algorithms. The DSM uses stereo xray-like projections, rapidly oscillating motion and focal depth cues such that detail can be studied in the spatial context of the entire set of data. Focal depth cues are generated with a lens and apeture algorithm that generates a plane of sharp focus, and multiple stereo pairs each with a different plane of sharp focus are generated and stored in the large memory for interactive selection using a physical or symbolic depth selector. More recent work is studying non-linear focussing. Psychophysical studies are underway to understand how people perce ive images on a volumetric display and how accurately 3 dimensional structures can be quantitated from these displays.
The specificity of cortical region KO to depth structure.
Tyler, Christopher W; Likova, Lora T; Kontsevich, Leonid L; Wade, Alex R
2006-03-01
Functional MRI studies have identified a cortical region designated as KO between retinotopic areas V3A/B and motion area V5 in human cortex as particularly responsive to motion-defined or kinetic borders. To determine the response of the KO region to more general aspects of structure, we used stereoscopic depth borders and disparate planes with no borders, together with three stimulus types that evoked no depth percept: luminance borders, line contours and illusory phase borders. Responses to these stimuli in the KO region were compared with the responses in retinotopically defined areas that have been variously associated with disparity processing in neurophysiological and fMRI studies. The strongest responses in the KO region were to stimuli evoking perceived depth structure from either disparity or motion cues, but it showed negligible responses either to luminance-based contour stimuli or to edgeless disparity stimuli. We conclude that the region designated as KO is best regarded as a primary center for the generic representation of depth structure rather than any kind of contour specificity.
Improved Boundary Layer Depth Retrievals from MPLNET
NASA Technical Reports Server (NTRS)
Lewis, Jasper R.; Welton, Ellsworth J.; Molod, Andrea M.; Joseph, Everette
2013-01-01
Continuous lidar observations of the planetary boundary layer (PBL) depth have been made at the Micropulse Lidar Network (MPLNET) site in Greenbelt, MD since April 2001. However, because of issues with the operational PBL depth algorithm, the data is not reliable for determining seasonal and diurnal trends. Therefore, an improved PBL depth algorithm has been developed which uses a combination of the wavelet technique and image processing. The new algorithm is less susceptible to contamination by clouds and residual layers, and in general, produces lower PBL depths. A 2010 comparison shows the operational algorithm overestimates the daily mean PBL depth when compared to the improved algorithm (1.85 and 1.07 km, respectively). The improved MPLNET PBL depths are validated using radiosonde comparisons which suggests the algorithm performs well to determine the depth of a fully developed PBL. A comparison with the Goddard Earth Observing System-version 5 (GEOS-5) model suggests that the model may underestimate the maximum daytime PBL depth by 410 m during the spring and summer. The best agreement between MPLNET and GEOS-5 occurred during the fall and they diered the most in the winter.
The perception of three-dimensionality across continuous surfaces
NASA Technical Reports Server (NTRS)
Stevens, Kent A.
1989-01-01
The apparent three-dimensionality of a viewed surface presumably corresponds to several internal preceptual quantities, such as surface curvature, local surface orientation, and depth. These quantities are mathematically related for points within the silhouette bounds of a smooth, continuous surface. For instance, surface curvature is related to the rate of change of local surface orientation, and surface orientation is related to the local gradient of distance. It is not clear to what extent these 3D quantities are determined directly from image information rather than indirectly from mathematically related forms, by differentiation or by integration within boundary constraints. An open empirical question, for example, is to what extent surface curvature is perceived directly, and to what extent it is quantitative rather than qualitative. In addition to surface orientation and curvature, one derives an impression of depth, i.e., variations in apparent egocentric distance. A static orthographic image is essentially devoid of depth information, and any quantitative depth impression must be inferred from surface orientation and other sources. Such conversion of orientation to depth does appear to occur, and even to prevail over stereoscopic depth information under some circumstances.
Differential responses in dorsal visual cortex to motion and disparity depth cues
Arnoldussen, David M.; Goossens, Jeroen; van den Berg, Albert V.
2013-01-01
We investigated how interactions between monocular motion parallax and binocular cues to depth vary in human motion areas for wide-field visual motion stimuli (110 × 100°). We used fMRI with an extensive 2 × 3 × 2 factorial blocked design in which we combined two types of self-motion (translational motion and translational + rotational motion), with three categories of motion inflicted by the degree of noise (self-motion, distorted self-motion, and multiple object-motion), and two different view modes of the flow patterns (stereo and synoptic viewing). Interactions between disparity and motion category revealed distinct contributions to self- and object-motion processing in 3D. For cortical areas V6 and CSv, but not the anterior part of MT+ with bilateral visual responsiveness (MT+/b), we found a disparity-dependent effect of rotational flow and noise: When self-motion perception was degraded by adding rotational flow and moderate levels of noise, the BOLD responses were reduced compared with translational self-motion alone, but this reduction was cancelled by adding stereo information which also rescued the subject's self-motion percept. At high noise levels, when the self-motion percept gave way to a swarm of moving objects, the BOLD signal strongly increased compared to self-motion in areas MT+/b and V6, but only for stereo in the latter. BOLD response did not increase for either view mode in CSv. These different response patterns indicate different contributions of areas V6, MT+/b, and CSv to the processing of self-motion perception and the processing of multiple independent motions. PMID:24339808
Auto-converging stereo cameras for 3D robotic tele-operation
NASA Astrophysics Data System (ADS)
Edmondson, Richard; Aycock, Todd; Chenault, David
2012-06-01
Polaris Sensor Technologies has developed a Stereovision Upgrade Kit for TALON robot to provide enhanced depth perception to the operator. This kit previously required the TALON Operator Control Unit to be equipped with the optional touchscreen interface to allow for operator control of the camera convergence angle adjustment. This adjustment allowed for optimal camera convergence independent of the distance from the camera to the object being viewed. Polaris has recently improved the performance of the stereo camera by implementing an Automatic Convergence algorithm in a field programmable gate array in the camera assembly. This algorithm uses scene content to automatically adjust the camera convergence angle, freeing the operator to focus on the task rather than adjustment of the vision system. The autoconvergence capability has been demonstrated on both visible zoom cameras and longwave infrared microbolometer stereo pairs.
Improved evaluation of optical depth components from Langley plot data
NASA Technical Reports Server (NTRS)
Biggar, S. F.; Gellman, D. I.; Slater, P. N.
1990-01-01
A simple, iterative procedure to determine the optical depth components of the extinction optical depth measured by a solar radiometer is presented. Simulated data show that the iterative procedure improves the determination of the exponent of a Junge law particle size distribution. The determination of the optical depth due to aerosol scattering is improved as compared to a method which uses only two points from the extinction data. The iterative method was used to determine spectral optical depth components for June 11-13, 1988 during the MAC III experiment.
Perceived change in orientation from optic flow in the central visual field
NASA Technical Reports Server (NTRS)
Dyre, Brian P.; Andersen, George J.
1988-01-01
The effects of internal depth within a simulation display on perceived changes in orientation have been studied. Subjects monocularly viewed displays simulating observer motion within a volume of randomly positioned points through a window which limited the field of view to 15 deg. Changes in perceived spatial orientation were measured by changes in posture. The extent of internal depth within the display, the presence or absence of visual information specifying change in orientation, and the frequency of motion supplied by the display were examined. It was found that increased sway occurred at frequencies equal to or below 0.375 Hz when motion at these frequencies was displayed. The extent of internal depth had no effect on the perception of changing orientation.
Measuring sensitivity to viewpoint change with and without stereoscopic cues.
Bell, Jason; Dickinson, Edwin; Badcock, David R; Kingdom, Frederick A A
2013-12-04
The speed and accuracy of object recognition is compromised by a change in viewpoint; demonstrating that human observers are sensitive to this transformation. Here we discuss a novel method for simulating the appearance of an object that has undergone a rotation-in-depth, and include an exposition of the differences between perspective and orthographic projections. Next we describe a method by which human sensitivity to rotation-in-depth can be measured. Finally we discuss an apparatus for creating a vivid percept of a 3-dimensional rotation-in-depth; the Wheatstone Eight Mirror Stereoscope. By doing so, we reveal a means by which to evaluate the role of stereoscopic cues in the discrimination of viewpoint rotated shapes and objects.
A clustering approach to segmenting users of internet-based risk calculators.
Harle, C A; Downs, J S; Padman, R
2011-01-01
Risk calculators are widely available Internet applications that deliver quantitative health risk estimates to consumers. Although these tools are known to have varying effects on risk perceptions, little is known about who will be more likely to accept objective risk estimates. To identify clusters of online health consumers that help explain variation in individual improvement in risk perceptions from web-based quantitative disease risk information. A secondary analysis was performed on data collected in a field experiment that measured people's pre-diabetes risk perceptions before and after visiting a realistic health promotion website that provided quantitative risk information. K-means clustering was performed on numerous candidate variable sets, and the different segmentations were evaluated based on between-cluster variation in risk perception improvement. Variation in responses to risk information was best explained by clustering on pre-intervention absolute pre-diabetes risk perceptions and an objective estimate of personal risk. Members of a high-risk overestimater cluster showed large improvements in their risk perceptions, but clusters of both moderate-risk and high-risk underestimaters were much more muted in improving their optimistically biased perceptions. Cluster analysis provided a unique approach for segmenting health consumers and predicting their acceptance of quantitative disease risk information. These clusters suggest that health consumers were very responsive to good news, but tended not to incorporate bad news into their self-perceptions much. These findings help to quantify variation among online health consumers and may inform the targeted marketing of and improvements to risk communication tools on the Internet.
Oba, Sandra I.; Galvin, John J.; Fu, Qian-Jie
2014-01-01
Auditory training has been shown to significantly improve cochlear implant (CI) users’ speech and music perception. However, it is unclear whether post-training gains in performance were due to improved auditory perception or to generally improved attention, memory and/or cognitive processing. In this study, speech and music perception, as well as auditory and visual memory were assessed in ten CI users before, during, and after training with a non-auditory task. A visual digit span (VDS) task was used for training, in which subjects recalled sequences of digits presented visually. After the VDS training, VDS performance significantly improved. However, there were no significant improvements for most auditory outcome measures (auditory digit span, phoneme recognition, sentence recognition in noise, digit recognition in noise), except for small (but significant) improvements in vocal emotion recognition and melodic contour identification. Post-training gains were much smaller with the non-auditory VDS training than observed in previous auditory training studies with CI users. The results suggest that post-training gains observed in previous studies were not solely attributable to improved attention or memory, and were more likely due to improved auditory perception. The results also suggest that CI users may require targeted auditory training to improve speech and music perception. PMID:23516087
Uzochukwu, Benjamin S C; Onwujekwe, Emmanuel; Ezuma, Nkoli N; Ezeoke, Ogochukwu P; Ajuba, Miriam O; Sibeudu, Florence T
2011-01-31
Developments in rapid diagnostic tests (RDTs) have opened new possibilities for improved remote malaria diagnosis that is independent of microscopic diagnosis. Studies in some settings have tried to assess the influence of RDTs on the prescribing behaviour of health workers, but such information is generally lacking in Nigeria and many parts of sub-Saharan Africa. This study analysed health workers' perceptions of RDTs and their potential influence on their prescribing and treatment practices after their introduction. The study was conducted in four health centers in the Enugu East local government of Enugu State, Nigeria. All 32 health workers in the health centers where RDTs were deployed were interviewed by field workers. Information was sought on their perception of symptoms-based, RDT-based, and microscopy-based malaria diagnoses. In addition, prescription analysis was carried out on 400 prescriptions before and 12 months after RDT deployment. The majority of the health workers perceived RDTs to be more effective for malaria diagnosis than microscopy and clinical diagnosis. They also felt that the benefits of RDTs included increased use of RDTs in the facilities and the tendency to prescribe more Artemisinin-based combination therapies (ACTs) and less chloroquine and SP. Some of the health workers experienced some difficulties in the process of using RDT kits. ACTs were prescribed in 74% of RDT-negative results. RDT-supported malaria diagnosis may have led to the overprescription of ACTs, with the drug being prescribed to people with RDT-negative results. However, the prescription of other antimalarial drugs that are not first-line drugs has been reduced. Efforts should be made to encourage health workers to trust RDT results and prescribe ACTs only to those with positive RDT results. In-depth studies are needed to determine why health workers continue to prescribe ACTs in RDT-negative results.
Krishnan, Anand; Amarchand, Ritvik; Byass, Peter; Pandav, Chandrakant; Ng, Nawi
2014-01-31
Haryana was the first state in India to launch a conditional cash transfer (CCT) scheme in 1994. Initially it targeted all disadvantaged girls but was revised in 2005 to restrict it to second girl children of all groups. The benefit which accrued at girl attaining 18 years and subject to conditionalities of being fully immunized, studying till class 10 and remaining unmarried, was increased from about US$ 500 to US$ 2000. Using a mixed methods approach, we evaluated the implementation and possible impact of these two schemes. A survey was conducted among 200 randomly selected respondents of Ballabgarh Block in Haryana to assess their perceptions of girl children and related schemes. A cohort of births during this period was assembled from population database of 28 villages in this block and changes in sex ratio at birth and in immunization coverage at one year of age among boys and girls was measured. Education levels and mean age at marriage of daughters were compared with daughters-in-law from outside Haryana. In-depth interviews were conducted among district level implementers of these schemes to assess their perceptions of programs' implementation and impact. These were analyzed using a thematic approach. The perceptions of girls as a liability and poor (9% to 15%) awareness of the schemes was noted. The cohort analysis showed that while there has been an improvement in the indicators studied, these were similar to those seen among the control groups. Qualitative analysis identified a "conspiracy of silence" - an underplaying of the pervasiveness of the problem coupled with a passive implementation of the program and a clash between political culture of giving subsidies and a bureaucratic approach that imposed many conditionalities and documentary needs for availing of benefits. The apparent lack of impact on the societal mindset calls for a revision in the current approach of addressing a social issue by a purely conditional cash transfer program.
Jordan, Joanne E; Chua, Jason; Schütze, Robert; Wark, John D
2016-01-01
Objective To investigate young people's experiences of persistent musculoskeletal pain, including care needs and current service gaps as well as perceptions about the role of digital technologies to support their co-care. Methods A qualitative study employing two independent data collection modes: in-depth individual semistructured interviews and focus groups. Setting Community settings throughout Australia. Participants Participants were included if they had experienced persistent musculoskeletal pain of >3-month duration with an average of ≥3 on the visual analogue scale over the preceding 3 months, including non-specific conditions (eg, low back pain) and specific conditions (eg, juvenile idiopathic arthritis and other systemic arthritides), with/without pre-existing or current diagnosed mental health conditions. 23 young people (87.0% women; mean (SD) age: 20.8 (2.4) years) from across 6 Australian jurisdictions participated. Almost two-thirds of participants with persistent musculoskeletal pain reported comorbid mental health conditions. Main outcome measures Inductive and deductive approaches to analyse and derive key themes from verbatim transcripts. Results Participants described their daily experiences of living with persistent musculoskeletal pain, their fears and the challenges imposed by the invisibility of pain, and the two-way relationship between their pain and mental well-being. A lack of relevant and accessible information and resources tailored to young people's unique needs, integrated and youth-relevant healthcare services and adequately skilled healthcare practitioners were identified as key care gaps. Participants strongly advocated for the use of digital technologies to improve access to age-appropriate resources and support for co-care. Conclusions Young people living with persistent musculoskeletal pain described the absence of age-appropriate pain services and clearly articulated their perceptions on the role of, and opportunities provided by, digital technologies to connect with and support improved pain healthcare. Innovative and digitally-enabled models of pain care are likely to be helpful for this group. PMID:27940635
Miao, Melissa; Power, Emma; O'Halloran, Robyn
2015-01-01
Although clinical practice guidelines can facilitate evidence-based practice and improve the health outcomes of stroke patients, they continue to be underutilised. There is limited research into the reasons for this, especially in speech pathology. This study provides the first in-depth, qualitative examination of the barriers and facilitators that speech pathologists perceive and experience when implementing guidelines. A maximum variation sample of eight speech pathologists participated in a semi-structured interview concerning the implementation of the National Stroke Foundation's Clinical Guidelines for Stroke Management 2010. Interviews were transcribed, thematically analysed and member checked before overall themes were identified. Three main themes and ten subthemes were identified. The first main theme, making implementation explicit, reflected the necessity of accessing and understanding guideline recommendations, and focussing specifically on implementation in context. In the second theme, demand versus ability to change, the size of changes required was compared with available resources and collaboration. The final theme, Speech pathologist motivation to implement guidelines, demonstrated the influence of individual perception of the guidelines and personal commitment to improved practice. Factors affecting implementation are complex, and are not exclusively barriers or facilitators. Some potential implementation strategies are suggested. Further research is recommended. In most Western nations, stroke remains the single greatest cause of disability, including communication and swallowing disabilities. Although adherence to stroke clinical practice guidelines improves stroke patient outcomes, guidelines continue to be underutilised, and the reasons for this are not well understood. This is the first in-depth qualitative study identifying the complex barriers and facilitators to guideline implementation as experienced by speech pathologists in stroke care. Suggested implementation strategies include local monitoring of guideline implementation (e.g. team meetings, audits), increasing collaboration on implementation projects (e.g. managerial involvement, networking), and seeking speech pathologist input into guideline development.
Hickin, Sharon L; White, Sandra; Knopp-Sihota, Jennifer
2017-08-01
To determine the impact of education on nurses' knowledge of delirium, knowledge and perception of a validated screening tool, and delirium screening in the ICU. A quasi-experimental single group pretest-post-test design. A 16 bed ICU in a Canadian urban tertiary care centre. Nursing knowledge and perception were measured at baseline, 3-month and 18-month periods. Delirium screening was then assessed over 24-months. During the study period, 197 surveys were returned; 84 at baseline, 53 at 3-months post education, and 60 at the final assessment period 18-months post intervention. The significant improvements in mean knowledge scores at 3-months post intervention (7.2, SD 1.3) were not maintained at 18-months (5.3, SD 1.1). Screening tool perception scores remained unchanged. Improvements in the perception of utility were significant at both time periods (p=0.03, 0.02 respectively). Physician value significantly improved at 18-months (p=0.01). Delirium screening frequency improved after education (p<0.001) demonstrating a positive correlation over time (p<0.01). Multifaceted education is effective in improving delirium knowledge and screening; however, without sustained effort, progress is transient. Education improved perceived tool utility and over time utility perception and physician value improved. Copyright © 2017 Elsevier Ltd. All rights reserved.
Stereoscopic depth increases intersubject correlations of brain networks.
Gaebler, Michael; Biessmann, Felix; Lamke, Jan-Peter; Müller, Klaus-Robert; Walter, Henrik; Hetzer, Stefan
2014-10-15
Three-dimensional movies presented via stereoscopic displays have become more popular in recent years aiming at a more engaging viewing experience. However, neurocognitive processes associated with the perception of stereoscopic depth in complex and dynamic visual stimuli remain understudied. Here, we investigate the influence of stereoscopic depth on both neurophysiology and subjective experience. Using multivariate statistical learning methods, we compare the brain activity of subjects when freely watching the same movies in 2D and in 3D. Subjective reports indicate that 3D movies are more strongly experienced than 2D movies. On the neural level, we observe significantly higher intersubject correlations of cortical networks when subjects are watching 3D movies relative to the same movies in 2D. We demonstrate that increases in intersubject correlations of brain networks can serve as neurophysiological marker for stereoscopic depth and for the strength of the viewing experience. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
Ethical Becoming: Adult Ethical Development in Christian Congregations
ERIC Educational Resources Information Center
Carr-Chellman, Davin J.
2011-01-01
This is a study of adult ethical development in Christian congregations. Using an empirical hermeneutic phenomenological methodology, this study examined how five pastors understand and encourage ethical development, developing an in-depth analysis and interpretation of their perceptions of the phenomenon of adult ethical development. Two primary…
Professional Development Models That Promote Teacher Change and Impact Student Achievement
ERIC Educational Resources Information Center
Hawkins, Dawn
2017-01-01
To capture participants' perspectives regarding their experiences in South Carolina's Upstate Writing Project professional development, a series of in-depth, qualitative interviews was conducted with four teachers and two curriculum coaches from participating districts. Data provided insight into participant's perceptions of how their experiences…
Elementary School Counselors' Collaboration with Community Mental Health Providers
ERIC Educational Resources Information Center
Moran, Kristen; Bodenhorn, Nancy
2015-01-01
Perceptions and experiences of elementary school counselors' collaborative efforts with community mental health providers are examined through this exploratory phenomenological study. Ten participants engaged in two in-depth interviews. Collaboration was considered an effective way to increase services to students and their families. Six themes…
Students' Perspectives on Gatekeeping in Counselor Education: A Case Study
ERIC Educational Resources Information Center
Foster, Jennifer M.; Leppma, Monica; Hutchinson, Tracy S.
2014-01-01
Through in-depth interviews, the authors examined 10 master's-level counseling students' perceptions of gatekeeping. Case analysis resulted in 3 major themes pertaining to the necessity of gatekeeping, vital components, and counseling student characteristics. Implications of the findings are also discussed.
Developing Leadership: Exploring Childhoods of Women University Presidents
ERIC Educational Resources Information Center
Madsen, Susan R.
2007-01-01
Purpose: Researchers argue that much of who we are is developed during childhood. Yet, little exploratory research has been conducted regarding the childhood experiences, activities, personalities, and perceptions of successful leaders. This paper aims to address this issue. Design/methodology/approach: In-depth, qualitative interviews were…
Color constrains depth in da Vinci stereopsis for camouflage but not occlusion.
Wardle, Susan G; Gillam, Barbara J
2013-12-01
Monocular regions that occur with binocular viewing of natural scenes can produce a strong perception of depth--"da Vinci stereopsis." They occur either when part of the background is occluded in one eye, or when a nearer object is camouflaged against a background surface in one eye's view. There has been some controversy over whether da Vinci depth is constrained by geometric or ecological factors. Here we show that the color of the monocular region constrains the depth perceived from camouflage, but not occlusion, as predicted by ecological considerations. Quantitative depth was found in both cases, but for camouflage only when the color of the monocular region matched the binocular background. Unlike previous reports, depth failed even when nonmatching colors satisfied conditions for perceptual transparency. We show that placing a colored line at the boundary between the binocular and monocular regions is sufficient to eliminate depth from camouflage. When both the background and the monocular region contained vertical contours that could be fused, some observers appeared to use fusion, and others da Vinci constraints, supporting the existence of a separate da Vinci mechanism. The results show that da Vinci stereopsis incorporates color constraints and is more complex than previously assumed.
Perceptions of Healthy Eating in Four Alberta Communities: A Photovoice Project
Hammer, Brent A.; Vallianatos, Helen; Nieuwendyk, Laura M.
2016-01-01
Peoples’ perceptions of healthy eating are influenced by the cultural context in which they occur. Despite this general acceptance by health practitioners and social scientists, studies suggest that there remains a relative homogeneity around peoples’ perceptions that informs a hegemonic discourse around healthy eating. People often describe healthy eating in terms of learned information from sources that reflect societies’ norms and values, such as the Canada Food Guide and the ubiquitous phrase “fruits and vegetables”. Past research has examined how built environments shape people’s access to healthy living options, such as distribution of grocers versus convenience stores and fast food restaurants. Often overlooked is an in-depth understanding of how social contexts interact with built environments, molding peoples’ perceptions of healthy eating. This paper reports on perceptions of healthy eating in four communities across Alberta, Canada. A photovoice methodology was employed to elicit perceptions of healthy eating with 35 participants. This study illustrates how participants’ photographs and their stories convey multiple meanings about healthy eating within their own lives and communities. Findings suggest that a ‘local’ context is an important part of the discourse centered around the promotion of healthy eating practices in these and potential other communities. PMID:27390390
Perceptions of Healthy Eating in Four Alberta Communities: A Photovoice Project.
Hammer, Brent A; Vallianatos, Helen; Nykiforuk, Candace; Nieuwendyk, Laura M
2015-01-23
Peoples' perceptions of healthy eating are influenced by the cultural context in which they occur. Despite this general acceptance by health practitioners and social scientists, studies suggest that there remains a relative homogeneity around peoples' perceptions that informs a hegemonic discourse around healthy eating. People often describe healthy eating in terms of learned information from sources that reflect societies' norms and values, such as the Canada Food Guide and the ubiquitous phrase "fruits and vegetables". Past research has examined how built environments shape people's access to healthy living options, such as distribution of grocers versus convenience stores and fast food restaurants. Often overlooked is an in-depth understanding of how social contexts interact with built environments, molding peoples' perceptions of healthy eating. This paper reports on perceptions of healthy eating in four communities across Alberta, Canada. A photovoice methodology was employed to elicit perceptions of healthy eating with 35 participants. This study illustrates how participants' photographs and their stories convey multiple meanings about healthy eating within their own lives and communities. Findings suggest that a 'local' context is an important part of the discourse centered around the promotion of healthy eating practices in these and potential other communities.
1991-05-13
for the model classroom. Nevertheless, findings about the impact of interior design improvements 14 on student perceptions about the physical...from the impact of the model classroom interior design improvements on student perceptions about their physical learning environment. Delimitations of...their perceptions about places through personal experience. The intensity and quality of these personal experiences have a greater impact on people’s
Risk perception and moralization among smokers in the USA and Denmark: a qualitative approach.
Helweg-Larsen, Marie; Tobias, Margaret R; Cerban, Bettina M
2010-11-01
The present research explored the role that culture plays in smokers' description of their risk perceptions and experiences as targets of moralization. We conducted in-depth qualitative interviews with 15 smokers each from Denmark (a smoking-lenient culture) and the USA (a smoking-prohibitive culture). Smokers said they were well aware of the risks of smoking yet minimized the risks of active and passive smoking; Danes were particularly likely to minimize these risks. Smokers also described many experiences as targets of moralization and accepted some elements of moralized attitudes although overall Danes more strongly rejected moralized opinions. Smokers described adjusting to moralization by changing when and where but not how much they smoked. It is important to consider cultural influences on moralization and risk perception of smoking.
Gordon, Karen A.; Papsin, Blake C.; Nespoli, Gabe; Hopyan, Talar; Peretz, Isabelle; Russo, Frank A.
2017-01-01
Objectives: Children who use cochlear implants (CIs) have characteristic pitch processing deficits leading to impairments in music perception and in understanding emotional intention in spoken language. Music training for normal-hearing children has previously been shown to benefit perception of emotional prosody. The purpose of the present study was to assess whether deaf children who use CIs obtain similar benefits from music training. We hypothesized that music training would lead to gains in auditory processing and that these gains would transfer to emotional speech prosody perception. Design: Study participants were 18 child CI users (ages 6 to 15). Participants received either 6 months of music training (i.e., individualized piano lessons) or 6 months of visual art training (i.e., individualized painting lessons). Measures of music perception and emotional speech prosody perception were obtained pre-, mid-, and post-training. The Montreal Battery for Evaluation of Musical Abilities was used to measure five different aspects of music perception (scale, contour, interval, rhythm, and incidental memory). The emotional speech prosody task required participants to identify the emotional intention of a semantically neutral sentence under audio-only and audiovisual conditions. Results: Music training led to improved performance on tasks requiring the discrimination of melodic contour and rhythm, as well as incidental memory for melodies. These improvements were predominantly found from mid- to post-training. Critically, music training also improved emotional speech prosody perception. Music training was most advantageous in audio-only conditions. Art training did not lead to the same improvements. Conclusions: Music training can lead to improvements in perception of music and emotional speech prosody, and thus may be an effective supplementary technique for supporting auditory rehabilitation following cochlear implantation. PMID:28085739
Good, Arla; Gordon, Karen A; Papsin, Blake C; Nespoli, Gabe; Hopyan, Talar; Peretz, Isabelle; Russo, Frank A
Children who use cochlear implants (CIs) have characteristic pitch processing deficits leading to impairments in music perception and in understanding emotional intention in spoken language. Music training for normal-hearing children has previously been shown to benefit perception of emotional prosody. The purpose of the present study was to assess whether deaf children who use CIs obtain similar benefits from music training. We hypothesized that music training would lead to gains in auditory processing and that these gains would transfer to emotional speech prosody perception. Study participants were 18 child CI users (ages 6 to 15). Participants received either 6 months of music training (i.e., individualized piano lessons) or 6 months of visual art training (i.e., individualized painting lessons). Measures of music perception and emotional speech prosody perception were obtained pre-, mid-, and post-training. The Montreal Battery for Evaluation of Musical Abilities was used to measure five different aspects of music perception (scale, contour, interval, rhythm, and incidental memory). The emotional speech prosody task required participants to identify the emotional intention of a semantically neutral sentence under audio-only and audiovisual conditions. Music training led to improved performance on tasks requiring the discrimination of melodic contour and rhythm, as well as incidental memory for melodies. These improvements were predominantly found from mid- to post-training. Critically, music training also improved emotional speech prosody perception. Music training was most advantageous in audio-only conditions. Art training did not lead to the same improvements. Music training can lead to improvements in perception of music and emotional speech prosody, and thus may be an effective supplementary technique for supporting auditory rehabilitation following cochlear implantation.
ERIC Educational Resources Information Center
Alotaibi, Faihan; Almalki, Nabil
2016-01-01
This study aimed at examining Saudi Teachers' Perceptions of ICT Implementation for Student with Autism Spectrum Disorder at Mainstream Schools. Studies have shown that the use of ICT can improve learning activities of students' with autism through improved communication, better interactions and enhanced skills. However, the perceptions of…
Benefits of Exercise for the Quality of Life of Drug-Dependent Patients.
Giménez-Meseguer, Jorge; Tortosa-Martínez, Juan; de los Remedios Fernández-Valenciano, María
2015-01-01
This study combined quantitative and qualitative research methods to evaluate quality-of-life changes in drug-dependent patients after participation in a group-based exercise program. Quality of life (SF-36) and physical fitness (six-minute Walk Test, Timed Get Up and Go Test, and Chair Stand Test) were quantitatively determined in a group (n=37) of drug-dependent patients before and after a 12-week group exercise program (n=18) or routine care (n=19). Additionally, in-depth interviews were conducted at the end of the program with a subsample of 11 participants from the exercise group. Quantitative results showed improvements in fitness and different aspects of quality of life, such as physical function, mental health, vitality, social function, and general health perception. Qualitative results showed specific physical benefits (decreased injuries and muscle pain, decreased weight, and increased vitality with improvement in activities of daily living), psychological benefits (forgetting about everyday problems, improved mood, decreased stress and anxiety), social benefits, and a reduction in craving. The results of this study provide insight into the importance of exercise for the quality of life and recovery process of drug-dependent patients.
Improving Student Engagement in Veterinary Business Studies.
Armitage-Chan, Elizabeth; Jackson, Elizabeth
2018-01-01
Improving Student Engagement in Veterinary Business StudiesIn a densely packed veterinary curriculum, students may find it particularly challenging to engage in the less overtly clinical subjects, yet pressure from industry and an increasingly competitive employment market necessitate improved veterinary student education in business and management skills. We describe a curriculum intervention (formative reflective assignment) that optimizes workplace learning opportunities and aims to provide better student scaffolding for their in-context business learning. Students were asked to analyze a business practice they experienced during a period of extra-mural studies (external work placement). Following return to the college, they were then instructed to discuss their findings in their study group, and produce a group reflection on their learning. To better understand student engagement in this area, we analyzed individual and group components of the assignment. Thematic analysis revealed evidence of various depths of student engagement, and provided indications of the behaviors they used when engaging at different levels. Interactive and social practices (discussing business strategies with veterinary employees and student peers) appeared to facilitate student engagement, assist the perception of relevance of these skills, and encourage integration with other curriculum elements such as communication skills and clinical problem solving.
Arnold, Naomi Adele; Ng, Kim Tee; Jongman, Ellen Caroline; Hemsworth, Paul Hamilton
2007-11-01
The ability of cows (Bos taurus) to perceive depth has never been experimentally investigated. If cows can perceive depth, the milking pit in commercial milking facilities may be fear provoking for dairy cows, as past research has shown that most land-dwelling species possess an instinctive fear of heights. In the current study, 12 dairy heifers (1-year-old cows) were exposed to a milking pit (depth-exposed group) and 13 heifers (control group) were exposed to a standard change in the environment while they moved through a milking facility over a 5-day treatment period. Heifers in the depth-exposed group showed a higher heart rate (p < .05) and stopped more often (p < .05) than did those in the control group; persistence of heart rate but not of behavioral responses on repeated exposures indicated that some habituation to the depth stimulus had occurred. Depth exposure had no effect on cortisol concentrations or on ease of handling. These results indicate that heifers responded differently to a change in depth than they did to a standard change in the environment and provide evidence of both depth perception and acute fear of heights in cows. Copyright 2007 APA.
Networking Activities and Perceptions of HIV Risk Among Male Migrant Market Vendors in China
Wang, Wenqing; Muessig, Kathryn E.; Li, Mingqiang; Zhang, Yingxia
2013-01-01
HIV research among internal migrants in China has not fully explored the contexts and perceptions of “risk”. In 2011, urban markets in Liuzhou, China were mapped, and sixty male vendors, age 22 to 56, were selected for in-depth interviews on migration, social and family life, and perceptions and practices of sexual risk behavior. Participants were evenly divided among higher income shop and small stall vendors. All men were sexually active. Only the shop vendors reported non-marital sexual partners, including concurrent partners (n=15), commercial partners (n=10), and other sexual relationships (n=11). Shop vendors engaged in networking activities that facilitated commercial and non-commercial high-risk sex. Perceptions of HIV risk from commercial sex led some men to doubt the protective ability of condoms and rely on local (unproven) self-protection techniques. Networking activities played a role in high-risk sex and shaping migrants' risk perceptions and health practices. The networks created through these processes could also be used to facilitate health promotion activities. PMID:23572155
Disadvantaged Former Miners' Perspectives on Smoking Cessation: A Qualitative Study
ERIC Educational Resources Information Center
White, Simon; Baird, Wendy
2013-01-01
Objective: To explore disadvantaged former miners' perspectives in north Derbyshire, United Kingdom (UK) on smoking and smoking cessation. Methods: In-depth, audiotaped interviews with 16 disadvantaged former miners who smoked or had stopped smoking within six months. Results: Perceptions of being able to stop smoking with minimal difficulty and…
Gendered Harassment in Secondary Schools: Understanding Teachers' (Non) Interventions
ERIC Educational Resources Information Center
Meyer, Elizabeth J.
2008-01-01
This article provides an analysis of teachers' perceptions of and responses to gendered harassment in Canadian secondary schools based on in-depth interviews with six teachers in one urban school district. Gendered harassment includes any behaviour that polices and reinforces traditional heterosexual gender norms such as (hetero)sexual harassment,…
Communicating with homeowners in the interface about defensible space
Martha C. Monroe; Michelle Payton
2006-01-01
Although resource managers encourage residents to create defensible space, many report that homeowners still live in risky landscapes. This study explores the perceptions and attitudes of Minnesota and Florida interface homeowners toward their local landscape. By using in-depth interviews, we gained a better understanding of landscape values, preferences, and...
Contour Entropy: A New Determinant of Perceiving Ground or a Hole
ERIC Educational Resources Information Center
Gillam, Barbara J.; Grove, Philip M.
2011-01-01
Figure-ground perception is typically described as seeing one surface occluding another. Figure properties, not ground properties, are considered the significant factors. In scenes, however, a near surface will often occlude multiple contours and surfaces, often at different depths, producing alignments that are improbable except under conditions…
Elite Cricket Coach Education: A Bourdieusian Analysis
ERIC Educational Resources Information Center
Townsend, Robert C.; Cushion, Christopher
2017-01-01
The social structures within coach education have been largely unexplored, undiscussed, and treated as unproblematic in contributing to coach learning, both in research and practice. The study used semi-structured, in-depth interviews with 11 elite cricket coaches to gather their perceptions of an elite coach education programme. In particular,…
Teacher Practices: How They Promote or Hinder Student Engagement in Mathematics
ERIC Educational Resources Information Center
Skilling, Karen
2014-01-01
With persistent concerns about student engagement, interest and participation in mathematics, this research investigated the range of practices 31 Year 7 mathematics teachers reported using and how they perceived these practices influenced student engagement in mathematics. In-depth interviews revealed similarities in teachers' perceptions of…
Financial Conditions: An In-Depth Look at Fiscal Troubles on Campus.
ERIC Educational Resources Information Center
Scoby, Jerry L.
1993-01-01
A survey of 300 college and university business officers investigated the extent of the institutions' financial difficulties. Results reveal administrators' perceptions of the reasons for and solutions to financial problems, factors in institutional stability or strength, plans to maintain or strengthen the institution's financial condition,…
The International Student's Experience: An Exploratory Study of Students from Vietnam
ERIC Educational Resources Information Center
Wearring, Andrew; Le, Huong; Wilson, Rachel; Arambewela, Rodney
2015-01-01
International students are an important part of today's global university sector. This paper explores, through 10 in-depth interviews, the perceptions of Vietnamese international students studying with regard to their experience of teaching and learning in Australia. The findings indicate that Vietnamese students struggle with language,…
What's Good about Being Gay? Perspectives from Youth
ERIC Educational Resources Information Center
Harper, Gary W.; Brodsky, Asya; Bruce, Douglas
2012-01-01
This article explores gay and bisexual male adolescents' positive perceptions of their sexual orientation identity. In-depth qualitative interviews were conducted with an ethnically diverse sample of 63 gay/bisexual male adolescents in Chicago (N = 42) and Miami (N = 21). Data revealed two major conceptual categories: (1) positive personal…
School Technology Leadership in a Spanish Secondary School: The TEI Model
ERIC Educational Resources Information Center
Gallego-Arrufat, María-Jesús; Gutiérrez-Santiuste, Elba; Campaña-Jiménez, Rafael Luis
2017-01-01
This study analyzes the perception that teachers and management team members in secondary school education have of "technology-based educational innovation" (TEI). Two questionnaires and in-depth interviews permit us to analyze leaders' perspective of planning, development, and evaluation. The school leaders' view diverges from that of…
Social Validity: Perceptions of Check and Connect with Early Literacy Support
ERIC Educational Resources Information Center
Miltich Lyst, Aimee; Gabriel, Stacey; O'Shaughnessy, Tam E.; Meyers, Joel; Meyers, Barbara
2005-01-01
This article underscores the potential advantages of qualitative methods to illustrate the depth and complexity of social validity. This investigation evaluates the social validity of Check and Connect with Early Literacy Support (CCEL), through the perspectives of teachers and caregivers whose children participated in the intervention. Teachers…
Sensory Sensitivities and Discriminations and their Roles in Aviation
1991-10-31
asymmetry. Neurology, in press. 5. Zihl JD, Von Cramon D & Mai N (1983) Selective disturbance of movement vision after bilateral brain damage. Brain...1970) Electrophysiological correlate of binocular depth perception in man. Nature 255, 92-4. 1971 16. Regan D & Sperling HG (1971) A method of evoking
Graduates' Work: Organisational Change and Students' Attributes.
ERIC Educational Resources Information Center
Harvey, Lee; Moon, Sue; Geall, Vicki; Bower, Ray
Employer and employee perceptions of the skills and abilities needed by college graduates in a changing workplace were examined through semistructured, in-depth interviews with a sample of 84 strategic managers, 84 college graduates, and 35 nongraduate employees in 91 organizations across England and Scotland that represented a mix of organization…
Professionalism: Doing a Good Job!
ERIC Educational Resources Information Center
Feather, Denis
2014-01-01
This paper considers the concept of professionalism via perceptions (real or imagined) of lecturers delivering higher education business programmes (HEBPs) in further education colleges in England. The study comprised 26 in-depth interviews conducted in the Yorkshire and Humber region in the UK. The study builds on Perkin's views of a professional…
Using an Artificial Rock Outcrop to Teach Geology
ERIC Educational Resources Information Center
Totten, Iris
2005-01-01
Teaching Earth science without exposure to rock outcrops limits students depth of understanding of Earth's processes, limits the concept of scale from their spatial visualization imaging, and distorts their perception of geologic time (Totten 2003). Through a grant funded by the National Science Foundation, an artificial rock outcrop was…
Women and the Superintendency: Perceptions of Gender Bias
ERIC Educational Resources Information Center
Garn, Gregg; Brown, Casey
2008-01-01
This research explored how 15 female superintendents from a southwestern state experienced issues of gender bias. Participants came from a mix of urban, rural, and suburban districts that varied in size from 150 to 25,000 students. Using in-depth interviews and a transcendental phenomenological qualitative approach, the researchers examined how…
Exploring Young Adult Sexual Minority Women's Perspectives on LGBTQ Smoking
ERIC Educational Resources Information Center
Youatt, Emily J.; Johns, Michelle M.; Pingel, Emily S.; Soler, Jorge H.; Bauermeister, José A.
2015-01-01
Smoking rates are higher among lesbian, gay, bisexual, transgender, and queer (LGBTQ) individuals than among heterosexuals. These disparities are exacerbated during the transition from youth to young adulthood. The current study uses in-depth qualitative interviews to understand perceptions of LGBTQ smoking among LBQ-identified women (N = 30, ages…
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…
Teacher Perceptions of Principals' Leadership Qualities: A Mixed Methods Study
ERIC Educational Resources Information Center
Hauserman, Cal P.; Ivankova, Nataliya V.; Stick, Sheldon L.
2013-01-01
This mixed methods sequential explanatory study utilized the Multi-factor Leadership Questionnaire, responses to open-ended questions, and in-depth interviews to identify transformational leadership qualities that were present among principals in Alberta, Canada. The first quantitative phase consisted of a random sample of 135 schools (with…
African American Girls' Ideal Dating Relationship Now and in the Future
ERIC Educational Resources Information Center
Debnam, Katrina J.; Howard, Donna E.; Garza, Mary A.; Green, Kerry M.
2017-01-01
Adolescence is a particularly important and challenging time for developing long-lasting romantic relationship patterns. However, limited empirical research has explored teen perceptions of ideal partner characteristics during adolescence or their significance to the quality of current and future relationships. Semi-structured in-depth interviews…
The Concept of Collection from the User's Perspective
ERIC Educational Resources Information Center
Lee, Hur-Li
2005-01-01
This study explores the concept and functions of collection from the perspective of the user. In-depth interviews with ten professors from a social science discipline and a natural science department provided descriptions of their information seeking involving material sources and their perceptions of the library collection. Participants used the…
Invisible Cultural Barriers: Contrasting Perspectives on Student Veterans' Transition
ERIC Educational Resources Information Center
Lim, Jae Hoon; Interiano, Claudia G.; Nowell, Caroline E.; Tkacik, Peter T.; Dahlberg, Jerry L.
2018-01-01
In this interpretative phenomenological study, the implicit cultural values and expectations embedded in faculty/staff's perceptions and how they functioned as a hidden curriculum against student veterans' smooth transition into higher education were analyzed based on in-depth interviews with 20 student veterans and 9 faculty/staff members. By…
16 CFR 1500.41 - Method of testing primary irritant substances.
Code of Federal Regulations, 2011 CFR
2011-01-01
...) to slight eschar formations (injuries in depth) 4 Edema formation: No edema 0 Very slight edema (barely perceptible) 1 Slight edema (edges of area well defined by definite raising) 2 Moderate edema (raised approximately 1 millimeter) 3 Severe edema (raised more than 1 millimeter and extending beyond the...
16 CFR 1500.41 - Method of testing primary irritant substances.
Code of Federal Regulations, 2010 CFR
2010-01-01
...) to slight eschar formations (injuries in depth) 4 Edema formation: No edema 0 Very slight edema (barely perceptible) 1 Slight edema (edges of area well defined by definite raising) 2 Moderate edema (raised approximately 1 millimeter) 3 Severe edema (raised more than 1 millimeter and extending beyond the...
ERIC Educational Resources Information Center
Susomrith, Pattanee; Coetzer, Alan
2015-01-01
Purpose: This paper aims to investigate barriers to employee participation in voluntary formal training and development opportunities from the perspective of employees in small engineering businesses. Design/methodology/approach: An exploratory qualitative methodology involving data collection via site visits and in-depth semi-structured…
Human perception testing methodology for evaluating EO/IR imaging systems
NASA Astrophysics Data System (ADS)
Graybeal, John J.; Monfort, Samuel S.; Du Bosq, Todd W.; Familoni, Babajide O.
2018-04-01
The U.S. Army's RDECOM CERDEC Night Vision and Electronic Sensors Directorate (NVESD) Perception Lab is tasked with supporting the development of sensor systems for the U.S. Army by evaluating human performance of emerging technologies. Typical research questions involve detection, recognition and identification as a function of range, blur, noise, spectral band, image processing techniques, image characteristics, and human factors. NVESD's Perception Lab provides an essential bridge between the physics of the imaging systems and the performance of the human operator. In addition to quantifying sensor performance, perception test results can also be used to generate models of human performance and to drive future sensor requirements. The Perception Lab seeks to develop and employ scientifically valid and efficient perception testing procedures within the practical constraints of Army research, including rapid development timelines for critical technologies, unique guidelines for ethical testing of Army personnel, and limited resources. The purpose of this paper is to describe NVESD Perception Lab capabilities, recent methodological improvements designed to align our methodology more closely with scientific best practice, and to discuss goals for future improvements and expanded capabilities. Specifically, we discuss modifying our methodology to improve training, to account for human fatigue, to improve assessments of human performance, and to increase experimental design consultation provided by research psychologists. Ultimately, this paper outlines a template for assessing human perception and overall system performance related to EO/IR imaging systems.
Disability assessment: the efficacy of multimedia interactive nurse education.
Chiang, Hui-Chaun; Lin, Feng-Yu; Hwu, Yueh-Juen
2013-06-01
Nearly 3% of the population in Taiwan is classified as disabled. Disability assessment directly relates to long-term care quality and resource allocation. The purpose of this study was to explore the effects of a multimedia interactive DVD on enhancing nurse knowledgeand disability assessment skills. The study was a quasi-experimental design. The experimental group received multimedia interactive DVD, and the control group received conventional classroom education. The study gathered data using scales assessing knowledge related to disability assessment and case studies. Scales were implemented before and after multimedia interactive DVD interventions at weeks 2 and 4. In-depth interviews with voice recording were used to collect qualitative data to elicit differences in perception between the experimental and control groups. This study found significant improvements in the experimental group in terms of disability assessment knowledge and case study assessment skills. These improvements lasted through at least 1-month posttest. Analysis of interview data for the experimental group showed that the multimedia interactive DVD provided a more flexible approach to learning than classroom education and improved participant self-confidence to conduct disability assessments. The study showed the effectiveness of the developed multimedia interactive DVD in significantly improving the disability assessment confidences of nurses. Study findings can be used as a reference guide for continuing educational efforts in long-term care settings.
Nurses' creativity: advantage or disadvantage.
Shahsavari Isfahani, Sara; Hosseini, Mohammad Ali; Fallahi Khoshknab, Masood; Peyrovi, Hamid; Khanke, Hamid Reza
2015-02-01
Recently, global nursing experts have been aggressively encouraging nurses to pursue creativity and innovation in nursing to improve nursing outcomes. Nurses' creativity plays a significant role in health and well-being. In most health systems across the world, nurses provide up to 80% of the primary health care; therefore, they are critically positioned to provide creative solutions for current and future global health challenges. The purpose of this study was to explore Iranian nurses' perceptions and experiences toward the expression of creativity in clinical settings and the outcomes of their creativity for health care organizations. A qualitative approach using content analysis was adopted. Data were collected through in-depth semistructured interviews with 14 nurses who were involved in the creative process in educational hospitals affiliated to Jahrom and Tehran Universities of Medical Sciences in Iran. Four themes emerged from the data analysis, including a) Improvement in quality of patient care, b) Improvement in nurses' quality of work, personal and social life, c) Promotion of organization, and d) Unpleasant outcomes. The findings indicated that nurses' creativity in health care organizations can lead to major changes of nursing practice, improvement of care and organizational performance. Therefore, policymakers, nurse educators, nursing and hospital managers should provide a nurturing environment that is conducive to creative thinking, giving the nurses opportunity for flexibility, creativity, support for change, and risk taking.
NASA Astrophysics Data System (ADS)
Dimitrievski, Martin; Goossens, Bart; Veelaert, Peter; Philips, Wilfried
2017-09-01
Understanding the 3D structure of the environment is advantageous for many tasks in the field of robotics and autonomous vehicles. From the robot's point of view, 3D perception is often formulated as a depth image reconstruction problem. In the literature, dense depth images are often recovered deterministically from stereo image disparities. Other systems use an expensive LiDAR sensor to produce accurate, but semi-sparse depth images. With the advent of deep learning there have also been attempts to estimate depth by only using monocular images. In this paper we combine the best of the two worlds, focusing on a combination of monocular images and low cost LiDAR point clouds. We explore the idea that very sparse depth information accurately captures the global scene structure while variations in image patches can be used to reconstruct local depth to a high resolution. The main contribution of this paper is a supervised learning depth reconstruction system based on a deep convolutional neural network. The network is trained on RGB image patches reinforced with sparse depth information and the output is a depth estimate for each pixel. Using image and point cloud data from the KITTI vision dataset we are able to learn a correspondence between local RGB information and local depth, while at the same time preserving the global scene structure. Our results are evaluated on sequences from the KITTI dataset and our own recordings using a low cost camera and LiDAR setup.
van Tulder, Raphael; Roth, Dominik; Laggner, Roberta; Krammel, Mario; Schriefl, Christoph; Kienbacher, Calvin; Novosad, Heinz; Chwojka, Constantin Christof; Sterz, Fritz; Havel, Christof; Schreiber, Wolfgang; Herkner, Harald
2017-02-01
The quality of telephone-assisted cardiopulmonary resuscitation (CPR) needs improvement. This study investigates whether a dispatchers' perception is an adequate measure of the actual quality of CPR provided by laypersons. Individual participant data from 3 randomized simulation trials, with identical methodology but different interventions, were combined for this analysis. Professional dispatchers gave telephone assistance to laypersons, who each provided 10 minutes of CPR on a manikin. Dispatchers were requested to classify the quality of providers' CPR as adequate or inadequate. Based on actual readings from manikins we classified providers' performance as adequate at 5-6 cm for depth and 100-120 compressions per minute (cpm) for rate. We calculated metrics of dispatcher accuracy. Six dispatchers rated the performance of 94 laypersons (38 women [42%]) with a mean (SD) age of 37 (14) years. In 905 analyzed minutes of telephone-assisted CPR, the mean compression depth and rate was 41 (13) mm and 98 (24) cpm, respectively. Analysis of dispatchers' diagnostic test accuracy for adequate compression depth yielded a sensitivity of 65% (95 CI 36%-95%) and specificity of 42% (95% CI, 32%-53%). Analysis of their assessment of adequate compression rate yielded a sensitivity of 75% (95% CI, 64%-86%) and specificity of 42% (95% CI, 32%-52%). Although dispatchers always underestimated the actual values of CPR parameters, the female dispatchers evaluations were less inaccurate than the evaluations of make dispatchers; the dispatchers overall (males and females together) underestimated the adequacy of female laypersons' CPR performance to a greater degree than female dispatchers did. The ability of dispatchers to estimate the quality of telephone-assisted CPR is limited. Dispatchers estimates of CPR adequacy needs to be studied further in order to find ways that telephone-assisted CPR might be improved.
Rutland, Catrin S; Dobbs, Heidi; Tötemeyer, Sabine
The first year of university is critical in shaping persistence decisions (whether students continue with and complete their degrees) and plays a formative role in influencing student attitudes and approaches to learning. Previous educational experiences, especially previous university education, shape the students' ability to adapt to the university environment and the study approaches they require to perform well in highly demanding professional programs such as medicine and veterinary medicine. The aim of this research was to explore the support mechanisms, academic achievements, and perception of students with different educational backgrounds in their first year of veterinary school. Using questionnaire data and examination grades, the effects upon perceptions, needs, and educational attainment in first-year students with and without prior university experience were analyzed to enable an in-depth understanding of their needs. Our findings show that school leavers (successfully completed secondary education, but no prior university experience) were outperformed in early exams by those who had previously graduated from university (even from unrelated degrees). Large variations in student perceptions and support needs were discovered between the two groups: graduate students perceived the difficulty and workload as less challenging and valued financial and IT support. Each student is an individual, but ensuring that universities understand their students and provide both academic and non-academic support is essential. This research explores the needs of veterinary students and offers insights into continued provision of support and improvements that can be made to help students achieve their potential and allow informed "Best Practice."
Adeagbo, O; Mullick, S; Pillay, D; Chersich, M; Morroni, C; Naidoo, N; Pleaner, M; Rees, H
2017-10-01
Background. The South African (SA) government introduced Implanon NXT, a long-acting subdermal contraceptive implant, in 2014 to expand contraceptive choice. Following an initial high uptake, its use declined considerably amid reports of early removals and frequent side-effects. We examine providers’ perceptions of training and attitudes towards Implanon NXT, as well as their views on the causes of early removals and the impact on the implant service. Objective. To assess healthcare providers’ perceptions and attitudes towards implant services in SA. Methods. In-depth interviews were conducted with eight nurses providing implant services in public facilities in Gauteng and North West Province. Emerging themes were identified, manually coded and thematically analysed following an interpretivism approach. Results. Nurses lacked confidence in providing implant services effectively, particularly removals, which they ascribed to the brief, cascade-type training received. Nurses generally held negative views towards the method. They also reported that side-effects are the most common reason for early removals – particularly irregular bleeding – and that men often do not support their partners who use the method. Lastly, it was found that providers require guidance on counselling regarding the method and standardised guidelines on the management of side-effects. Conclusion. Retraining and support of providers are needed to address competency gaps and negative attitudes towards the method. Assessment of providers’ readiness to perform removal procedures is also important. Finally, effective plans are necessary to improve implant continuation rates, especially among women whose partners are unsupportive. Creative Commons Attribution - NonCommercial Works License (CC BY-NC 4.0)
Madkour, Aubrey Spriggs; Swiatlo, Alison; Talan, Allison; LeSar, Kendra; Broussard, Marsha; Kendall, Carl; Seal, David
2016-10-01
Although teen dating violence victims' reticence in seeking help from adults is well documented, little is known about youths' comparative perceptions of the types of help offered by and effectiveness of various sources. This qualitative study solicited teens' perceptions of sources of help for victims using in-depth interviews with African American youth (ages 13-18) in two public high schools in New Orleans ( N = 38). Participants were recruited purposively by researchers during lunchtime and via referral by school personnel. Interviews were transcribed verbatim and coded independently by two study team members. Thematic content analyses were conducted. Teens reported that victims were most likely to seek help from friends, who were largely expected to provide advice and comfort. Nearly half reported that teens would be likely to seek help from family, who would provide more active responses to dating violence (i.e., reporting to authorities, confronting the abuser). Fewer respondents believed teens would seek help from other adults, such as school personnel, who were also perceived as likely to enlist outside authorities. Fears about lack of confidentiality and over-reaction were the main perceived barriers to accessing help from adults. Furthermore, although respondents believed teens would be less likely to seek help from adults, adults were perceived as more effective at stopping abuse compared with peers. Interventions that train peer helpers, explain confidentiality to teens, increase school personnel's ability to provide confidential counseling, and promote use of health services may improve access to help for teen dating violence victims.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Soria-Lara, Julio A., E-mail: j.a.sorialara@uva.nl; Bertolini, Luca, E-mail: l.bertolini@uva.nl; Brömmelstroet, Marco te, E-mail: M.C.G.teBrommelstroet@uva.nl
The effectiveness of EIA for evaluating transport planning projects is increasingly being questioned by practitioners, institutions and scholars. The academic literature has traditionally focused more on solving content-related problems with EIA (i.e. the measurement of environmental effects) than on process-related issues (i.e. the role of EIA in the planning process and the interaction between key actors). Focusing only on technical improvements is not sufficient for rectifying the effectiveness problems of EIA. In order to address this knowledge gap, the paper explores how EIA is experienced in the Spanish planning context and offers in-depth insight into EIA process-related issues in themore » field of urban transport planning. From the multitude of involved actors, the research focuses on exploring the perceptions of the two main professional groups: EIA developers and transport planners. Through a web-based survey we assess the importance of process-related barriers to the effective use of EIA in urban transport planning. The analyses revealed process issues based fundamentally on unstructured stakeholders involvement and an inefficient public participation - Highlights: • Qualitative research on perceptions of EIA participants on EIA processes. • Web-based survey with different participants (EIA-developers; transport planners). • It was seen an inefficient participation of stakeholders during the EIA processes.« less
Hweissa, N Ab; Lim, J N W; Su, T T
2016-09-01
In Libya, cervical cancer is ranked third as the most frequent cancer among women with early diagnosis being shown to reduce morbidity and mortality. Health-care providers can influence women's screening behaviours, and their lack of recommendations for screening can be one of the barriers that affect women's participation in screening programmes. This study aims to assess the health-care provider's perception around cervical cancer screening. In-depth, face-to-face interviews were conducted with 16 health-care providers, from both public and private sectors in Az-Zawiya city, Libya, between February and July of 2014. The interviews were recorded and transcribed, then analysed using thematic analysis. Our findings suggest that health-care providers did not provide sufficient information regarding cervical cancer screening for women who attend health-care facilities. The results highlight the role played by health-care professionals in motivating women to attend cervical cancer screening programs, and the need for health education of health-care providers to offer a precious advice regarding the screening. On the other hand, health-care providers highlighted that implementation of reminding system of cervical cancer screening will support them to improve screening attendance. In addition, health-care providers stressed the necessity for educational and awareness campaigns of cervical cancer screening among Libyan women. © 2016 John Wiley & Sons Ltd.
Day, Jenny; Taylor, Ann Clare Thorington; Summons, Peter; Van Der Riet, Pamela; Hunter, Sharyn; Maguire, Jane; Dilworth, Sophie; Bellchambers, Helen; Jeong, Sarah; Haydon, Gunilla; Harris, Margaret; Higgins, Isabel
2017-04-01
This paper reports phase one, conducted from March to June 2015, of a two-phase, qualitative descriptive study designed to explore the perceptions and experiences of older people before and after the introduction of consumer directed care (CDC) to home care packages (HCP) in Australia. Eligible consumers with a local HCP provider were mailed information about the study. Data collection occurred before the introduction of CDC and included face-to-face, in-depth interviews, summaries of interviews, field notes and reflective journaling. Semi-structured questions and 'emotional touchpoints' relating to home care were used to guide the interview conversation. Line-by-line data analysis, where significant statements were highlighted and clustered to reveal emergent themes, was used. Five older people, aged 81 to 91 years, participated in the study. The four emergent themes were: seeking quality and reciprocity in carer relationships; patchworking services; the waiting game; and technology with utility. Continuity of carers was central to the development of a trusting relationship and perceptions of care quality among older consumers. Care coordinators and workers should play a key role in ensuring older people receive timely information about CDC and their rights and responsibilities. Participants' use of contemporary technologies suggests opportunities to improve engagement of HCP clients in CDC.
Early vision and focal attention
NASA Astrophysics Data System (ADS)
Julesz, Bela
1991-07-01
At the thirty-year anniversary of the introduction of the technique of computer-generated random-dot stereograms and random-dot cinematograms into psychology, the impact of the technique on brain research and on the study of artificial intelligence is reviewed. The main finding-that stereoscopic depth perception (stereopsis), motion perception, and preattentive texture discrimination are basically bottom-up processes, which occur without the help of the top-down processes of cognition and semantic memory-greatly simplifies the study of these processes of early vision and permits the linking of human perception with monkey neurophysiology. Particularly interesting are the unexpected findings that stereopsis (assumed to be local) is a global process, while texture discrimination (assumed to be a global process, governed by statistics) is local, based on some conspicuous local features (textons). It is shown that the top-down process of "shape (depth) from shading" does not affect stereopsis, and some of the models of machine vision are evaluated. The asymmetry effect of human texture discrimination is discussed, together with recent nonlinear spatial filter models and a novel extension of the texton theory that can cope with the asymmetry problem. This didactic review attempts to introduce the physicist to the field of psychobiology and its problems-including metascientific problems of brain research, problems of scientific creativity, the state of artificial intelligence research (including connectionist neural networks) aimed at modeling brain activity, and the fundamental role of focal attention in mental events.
Improving depth resolutions in positron beam spectroscopy by concurrent ion-beam sputtering
NASA Astrophysics Data System (ADS)
John, Marco; Dalla, Ayham; Ibrahim, Alaa M.; Anwand, Wolfgang; Wagner, Andreas; Böttger, Roman; Krause-Rehberg, Reinhard
2018-05-01
The depth resolution of mono-energetic positron annihilation spectroscopy using a positron beam is shown to improve by concurrently removing the sample surface layer during positron beam spectroscopy. During ion-beam sputtering with argon ions, Doppler-broadening spectroscopy is performed with energies ranging from 3 keV to 5 keV allowing for high-resolution defect studies just below the sputtered surface. With this technique, significantly improved depth resolutions could be obtained even at larger depths when compared to standard positron beam experiments which suffer from extended positron implantation profiles at higher positron energies. Our results show that it is possible to investigate layered structures with a thickness of about 4 microns with significantly improved depth resolution. We demonstrated that a purposely generated ion-beam induced defect profile in a silicon sample could be resolved employing the new technique. A depth resolution of less than 100 nm could be reached.
A small business worksite wellness model for improving health behaviors.
Merrill, Ray M
2013-08-01
To evaluate the effectiveness of a wellness program delivered by WellSteps, LLC, aimed at improving employee health behaviors in small companies that lack the resources to independently develop and manage a wellness program. Analyses are based on 618 employees from five diverse companies that completed an initial personal health assessment. Exercise and dietary behaviors significantly improved across the five companies. Significant improvements in health perception and life satisfaction also resulted and were associated with improvements in health behaviors. Three of the five companies, each with fewer than 50 employees, were most effective in influencing positive health behaviors, health perceptions, and life satisfaction. The worksite wellness program effectively improved health behaviors, health perceptions, and life satisfaction.
Okereke, Ekechi; Tukur, Jamilu; Aminu, Amina; Butera, Jean; Mohammed, Bello; Tanko, Mustapha; Yisa, Ibrahim; Obonyo, Benson; Egboh, Mike
2015-02-15
An effective capacity building process for healthcare workers is required for the delivery of quality health care services. Work-based training can be applied for the capacity building of health care workers while causing minimum disruption to service delivery within health facilities. In 2012, clinical mentoring was introduced into the Jigawa State Health System through collaboration between the Jigawa State Ministry of Health and the Partnership for Transforming Health Systems Phase 2 (PATHS2). This study evaluates the perceptions of different stakeholders about clinical mentoring as a strategy for improving maternal, newborn and child health service delivery in Jigawa State, northern Nigeria. Interviews were conducted in February 2013 with different stakeholders within Jigawa State in Northern Nigeria. There were semi-structured interviews with 33 mentored health care workers as well as the health facility departmental heads for Obstetrics and Pediatrics in the selected clinical mentoring health facilities. In-depth interviews were also conducted with the clinical mentors and two senior government health officials working within the Jigawa State Ministry of Health. The qualitative data were audio-recorded; transcribed and thematically analysed. The study findings suggest that clinical mentoring improved service delivery within the clinical mentoring health facilities. Significant improvements in the professional capacity of mentored health workers were observed by clinical mentors, heads of departments and the mentored health workers. Best practices were introduced with the support of the clinical mentors such as appropriate baseline investigations for pediatric patients, the use of magnesium sulphate and misoprostol for the management of eclampsia and post-partum hemorrhage respectively. Government health officials indicate that clinical mentoring has led to more emphasis on the need for the provision of better quality health services. Stakeholders report that the introduction of clinical mentoring into the Jigawa State health system gave rise to an improved capacity of the mentored health care workers to deliver better quality maternal, newborn and child health services. It is anticipated that with a scale up of clinical mentoring, health outcomes will also significantly improve across northern Nigeria.
The role of spatial integration in the perception of surface orientation with active touch.
Giachritsis, Christos D; Wing, Alan M; Lovell, Paul G
2009-10-01
Vision research has shown that perception of line orientation, in the fovea area, improves with line length (Westheimer & Ley, 1997). This suggests that the visual system may use spatial integration to improve perception of orientation. In the present experiments, we investigated the role of spatial integration in the perception of surface orientation using kinesthetic and proprioceptive information from shoulder and elbow. With their left index fingers, participants actively explored virtual slanted surfaces of different lengths and orientations, and were asked to reproduce an orientation or discriminate between two orientations. Results showed that reproduction errors and discrimination thresholds improve with surface length. This suggests that the proprioceptive shoulder-elbow system may integrate redundant spatial information resulting from extended arm movements to improve orientation judgments.
Myers, Bronwyn; Williams, Petal Petersen; Johnson, Kim; Govender, Rajen; Manderscheid, Ron; Koch, J Randy
2016-02-22
In South Africa, concerns exist about the quality of substance abuse treatment. We developed a performance measurement system, known as the Service Quality Measures (SQM) initiative, to monitor the quality of treatment and assess efforts to improve quality of care. In 2014, the SQM system was implemented at six treatment sites to evaluate how implementation protocols could be improved in preparation for wider roll-out. To describe providers' perceptions of the feasibility and acceptability of implementing the SQM system, including barriers to and facilitators of implementation. We conducted 15 in-depth interviews (IDIs) with treatment providers from six treatment sites (two sites in KwaZulu-Natal and four in the Western Cape). Providers were asked about their experiences in implementing the system, the perceived feasibility of the system, and barriers to implementation. All IDIs were audio-recorded and transcribed verbatim. A framework approach was used to analyse the data. Providers reported that the SQM system was feasible to implement and acceptable to patients and providers. Issues identified through the IDIs included a perceived lack of clarity about sequencing of key elements in the implementation of the SQM system, questions on integration of the system into clinical care pathways, difficulties in tracking patients through the system, and concerns about maximising patient participation in the process. Findings suggest that the SQM system is feasible to implement and acceptable to providers, but that some refinements to the implementation protocols are needed to maximise patient participation and the likelihood of sustained implementation.
Why are breastfeeding rates low in Lebanon? a qualitative study
2011-01-01
Background Breastfeeding is a cost-effective public health intervention that reduces infant morbidity and mortality in developing countries. In Lebanon, breastfeeding exclusivity and continuation rates are disappointingly low. This qualitative study aims at identifying barriers and promoters of breastfeeding in the Lebanese context by exploring mothers' perceptions and experiences in breastfeeding over a one year period. Methods We conducted focus group discussions in three hospitals in Beirut, Lebanon, and followed up 36 breastfeeding mothers with serial in-depth interviews for one year post-partum or until breastfeeding discontinuation. Results Themes generated from baseline interviews revealed several positive and negative perceptions of breastfeeding. Longitudinal follow up identified insufficient milk, fear of weight gain or breast sagging, pain, sleep deprivation, exhaustion, or maternal employment, as reasons for early breastfeeding discontinuation. Women who continued breastfeeding for one year were more determined to succeed and overcome any barrier, relying mostly on family support and proper time management. Conclusions Increasing awareness of future mothers about breast feeding difficulties, its benefits to children, mothers, and society at large may further promote breastfeeding, and improve exclusivity and continuation rates in Lebanon. A national strategy for early intervention during school years to increase young women's awareness may improve their self-confidence and determination to succeed in breastfeeding later. Moreover, prolonging maternity leave, having day-care facilities at work, creation of lactation peer support groups and hotlines, and training of doctors and nurses in proper lactation support may positively impact breastfeeding exclusivity and continuation rates. Further research is needed to assess the effectiveness of proposed interventions in the Lebanese context. PMID:21878101
Why are breastfeeding rates low in Lebanon? A qualitative study.
Nabulsi, Mona
2011-08-30
Breastfeeding is a cost-effective public health intervention that reduces infant morbidity and mortality in developing countries. In Lebanon, breastfeeding exclusivity and continuation rates are disappointingly low. This qualitative study aims at identifying barriers and promoters of breastfeeding in the Lebanese context by exploring mothers' perceptions and experiences in breastfeeding over a one year period. We conducted focus group discussions in three hospitals in Beirut, Lebanon, and followed up 36 breastfeeding mothers with serial in-depth interviews for one year post-partum or until breastfeeding discontinuation. Themes generated from baseline interviews revealed several positive and negative perceptions of breastfeeding. Longitudinal follow up identified insufficient milk, fear of weight gain or breast sagging, pain, sleep deprivation, exhaustion, or maternal employment, as reasons for early breastfeeding discontinuation. Women who continued breastfeeding for one year were more determined to succeed and overcome any barrier, relying mostly on family support and proper time management. Increasing awareness of future mothers about breast feeding difficulties, its benefits to children, mothers, and society at large may further promote breastfeeding, and improve exclusivity and continuation rates in Lebanon. A national strategy for early intervention during school years to increase young women's awareness may improve their self-confidence and determination to succeed in breastfeeding later. Moreover, prolonging maternity leave, having day-care facilities at work, creation of lactation peer support groups and hotlines, and training of doctors and nurses in proper lactation support may positively impact breastfeeding exclusivity and continuation rates. Further research is needed to assess the effectiveness of proposed interventions in the Lebanese context.
Okeke, T A; Okafor, H U; Uzochukwu, B S C
2006-07-01
Malaria remains one of the main causes of mortality among young children in sub-Saharan Africa. In Nigeria traditional healers play an important role in health care delivery and the majority of the population depend on them for most of their ailments. The aim of this study was to investigate the perceptions of traditional healers regarding causes, symptoms, treatment of uncomplicated malaria and referral practices for severe malaria with a view to developing appropriate intervention strategies aimed at improving referral practices for severe malaria. A qualitative study was carried out in Ugwogo-Nike, a rural community in south-east Nigeria, which included in-depth interviews with 23 traditional healers. The traditional healers believed that the treatment of severe malaria, especially convulsions, with herbal remedies was very effective. Some traditional healers were familiar with the signs and symptoms of malaria, but malaria was perceived as an environmentally related disease caused by heat from the scorching sun. The majority of traditional healers believed that convulsions are inherited from parents, while a minority attributed them to evil spirits. Most (16/23) will not refer cases to a health facility because they believe in the efficacy of their herbal remedies. The few that did refer did so after several stages of traditional treatment, which resulted in long delays of about two weeks before appropriate treatment was received. The fact that traditional healers are important providers of treatment for severe malaria, especially convulsions, underlines the need to enlist their support in efforts to improve referral practices for severe malaria.
False Color Terrain Model of Phoenix Workspace
NASA Technical Reports Server (NTRS)
2008-01-01
This is a terrain model of Phoenix's Robotic Arm workspace. It has been color coded by depth with a lander model for context. The model has been derived using images from the depth perception feature from Phoenix's Surface Stereo Imager (SSI). Red indicates low-lying areas that appear to be troughs. Blue indicates higher areas that appear to be polygons. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.Diffusion accessibility as a method for visualizing macromolecular surface geometry.
Tsai, Yingssu; Holton, Thomas; Yeates, Todd O
2015-10-01
Important three-dimensional spatial features such as depth and surface concavity can be difficult to convey clearly in the context of two-dimensional images. In the area of macromolecular visualization, the computer graphics technique of ray-tracing can be helpful, but further techniques for emphasizing surface concavity can give clearer perceptions of depth. The notion of diffusion accessibility is well-suited for emphasizing such features of macromolecular surfaces, but a method for calculating diffusion accessibility has not been made widely available. Here we make available a web-based platform that performs the necessary calculation by solving the Laplace equation for steady state diffusion, and produces scripts for visualization that emphasize surface depth by coloring according to diffusion accessibility. The URL is http://services.mbi.ucla.edu/DiffAcc/. © 2015 The Protein Society.
Music training improves pitch perception in prelingually deafened children with cochlear implants.
Chen, Joshua Kuang-Chao; Chuang, Ann Yi Chiun; McMahon, Catherine; Hsieh, Jen-Chuen; Tung, Tao-Hsin; Li, Lieber Po-Hung
2010-04-01
The comparatively poor music appreciation in patients with cochlear implants might be ascribed to an inadequate exposure to music; however, the effect of training on music perception in prelingually deafened children with cochlear implants remains unknown. This study aimed to investigate whether previous musical education improves pitch perception ability in these children. Twenty-seven children with congenital/prelingual deafness of profound degree were studied. Test stimuli consisted of 2 sequential piano tones, ranging from C (256 Hz) to B (495 Hz). Children were asked to identify the pitch relationship between the 2 tones (same, higher, or lower). Effects of musical training duration, pitch-interval size, current age, age of implantation, gender, and type of cochlear implant on accuracy of pitch perception were evaluated. The duration of musical training positively correlated with the correct rate of pitch perception. Pitch perception performance was better in children who had a cochlear implant and were older than 6 years than in those who were aged < or =6 years (ie, preschool). Effect of pitch-interval size was insignificant on pitch perception, and there was no correlation between pitch perception and the age of implantation, gender, or type of cochlear implant. Musical training seems to improve pitch perception ability in prelingually deafened children with a cochlear implant. Auditory plasticity might play an important role in such enhancement. This suggests that incorporation of a structured training program on music perception early in life and as part of the postoperative rehabilitation program for prelingually deafened children with cochlear implants would be beneficial. A longitudinal study is needed to show whether improvement of music performance in these children is measurable by use of auditory evoked potentials.
Koo, Fung Kuen
2011-10-01
This qualitative study explores how older Hong Kong ChineseAustralians perceive aging and to what extent this perception affects their participation in physical activities. The main methods used were in-depth interviews with 22 participants ranging in age from 60 to 91 years. Interviews were translated from Chinese (Cantonese) and transcribed into English. Content analysis was used to find recurring themes from the interview data. The main findings indicate that the perception of aging is to some extent influenced by culture. Some participants defined aging as being measured in years, and others defined it by the state of one's physical health, appearance, and capacity to continue fulfilling one's social roles. These perceptions strongly influenced their preferences for and participation in physical activities. Acknowledging the fact that Chinese-speaking people are not culturally homogeneous, this article makes some recommendations to health service providers with regard to the development of appropriate physical activity programs.
Equine Welfare in England and Wales: Exploration of Stakeholders' Understanding.
Horseman, Susan V; Buller, Henry; Mullan, Siobhan; Knowles, Toby G; Barr, Alistair R S; Whay, Helen R
2017-01-01
Investigating how those responsible for the care of nonhuman animals understand the concept of animal welfare is important for animal welfare improvement. In-depth interviews with 31 equine stakeholders were used to explore their perceptions and understanding of welfare. The results showed the stakeholders understood the concept of welfare in 4 ways. Firstly, welfare was understood in terms of the provision of resources-for example, food. Secondly, a "horse-centered" understanding of welfare was articulated; this understanding included the horses' mental state and was linked to natural behavior. Thirdly, the word welfare had negative connotations, and for some, good welfare was achieved through avoidance of negative states. Finally, interviewees discussed incidents that occurred in their own familiar contexts but suggested that these were not welfare problems. Evidence indicated that the ways in which equine stakeholders understood the concept of welfare might have been acting as a barrier to the alleviation of some equine welfare problems. There is a need for strategies aimed at improving equine welfare to consider stakeholder constructs of welfare and the ways in which these constructs are generated and acted upon.
2016-01-01
Binocular disparity is detected in the primary visual cortex by a process similar to calculation of local cross-correlation between left and right retinal images. As a consequence, correlation-based neural signals convey information about false disparities as well as the true disparity. The false responses in the initial disparity detectors are eliminated at later stages in order to encode only disparities of the features correctly matched between the two eyes. For a simple stimulus configuration, a feed-forward nonlinear process can transform the correlation signal into the match signal. For human observers, depth judgement is determined by a weighted sum of the correlation and match signals rather than depending solely on the latter. The relative weight changes with spatial and temporal parameters of the stimuli, allowing adaptive recruitment of the two computations under different visual circumstances. A full transformation from correlation-based to match-based representation occurs at the neuronal population level in cortical area V4 and manifests in single-neuron responses of inferior temporal and posterior parietal cortices. Neurons in area V5/MT represent disparity in a manner intermediate between the correlation and match signals. We propose that the correlation and match signals in these areas contribute to depth perception in a weighted, parallel manner. This article is part of the themed issue ‘Vision in our three-dimensional world’. PMID:27269600
Fujita, Ichiro; Doi, Takahiro
2016-06-19
Binocular disparity is detected in the primary visual cortex by a process similar to calculation of local cross-correlation between left and right retinal images. As a consequence, correlation-based neural signals convey information about false disparities as well as the true disparity. The false responses in the initial disparity detectors are eliminated at later stages in order to encode only disparities of the features correctly matched between the two eyes. For a simple stimulus configuration, a feed-forward nonlinear process can transform the correlation signal into the match signal. For human observers, depth judgement is determined by a weighted sum of the correlation and match signals rather than depending solely on the latter. The relative weight changes with spatial and temporal parameters of the stimuli, allowing adaptive recruitment of the two computations under different visual circumstances. A full transformation from correlation-based to match-based representation occurs at the neuronal population level in cortical area V4 and manifests in single-neuron responses of inferior temporal and posterior parietal cortices. Neurons in area V5/MT represent disparity in a manner intermediate between the correlation and match signals. We propose that the correlation and match signals in these areas contribute to depth perception in a weighted, parallel manner.This article is part of the themed issue 'Vision in our three-dimensional world'. © 2016 The Author(s).
Cohen, Jennifer H; Foglia, Mary Beth; Kwong, Katherine; Pearlman, Robert; Fox, Ellen
2015-01-01
Healthcare organizations with an ethical culture experience higher levels of employee productivity, less staff turnover, better levels of patient safety, resource and cost savings, and higher levels of patient satisfaction. Employees' perceptions of the ethics of their organization are considered a good indicator of the ethics culture. How employees rate the ethics of their organization is not well understood. Previous research has identified a number of attributes that are salient to employees' perceptions in this area. However, little is known about how employees synthesize their perceptions of these attributes to rate the ethics of their organization. Without this knowledge, managers have little specific information to act on to improve practices that would in turn improve employees' perceptions of their organization's ethics. For this study, we used data from Department of Veterans Affairs' (VA) 2014 IntegratedEthics@ Staff Survey administered to Veterans Health Administration (VHA) staff. We used multivariate regression analyses to investigate how VHA employees weigh their perceptions of eight attributes of an ethical organization to inform an overall rating of the ethics of their organization. We found that employee perceptions of fairness, clarity of expectations, accountability, and leadership's prioritization of ethics had the strongest associations with the overall rating. In addition, employees disproportionately weighed their positive perceptions in determining their overall rating. Therefore, a strategy to improve employees' perceptions of these attributes could potentially have the greatest marginal return on investment with respect to improving employees' perceptions of the ethics of an organization.
Domestic waste disposal practice and perceptions of private sector waste management in urban Accra
2014-01-01
Background Waste poses a threat to public health and the environment if it is not stored, collected, and disposed of properly. The perception of waste as an unwanted material with no intrinsic value has dominated attitudes towards disposal. This study investigates the domestic waste practices, waste disposal, and perceptions about waste and health in an urban community. Methods The study utilised a mixed-method approach. A cross-sectional survey questionnaire and in-depth interview were used to collect data. A total of 364 household heads were interviewed in the survey and six key informants were interviewed with the in-depth interviews. Results The results of the study revealed that 93.1% of households disposed of food debris as waste and 77.8% disposed of plastic materials as waste. The study also showed that 61.0% of the households disposed of their waste at community bins or had waste picked up at their homes by private contractors. The remaining 39.0% disposed of their waste in gutters, streets, holes and nearby bushes. Of those who paid for the services of private contractors, 62.9% were not satisfied with the services because of their cost and irregular collection. About 83% of the respondents were aware that improper waste management contributes to disease causation; most of the respondents thought that improper waste management could lead to malaria and diarrhoea. There was a general perception that children should be responsible for transporting waste from the households to dumping sites. Conclusion Proper education of the public, the provision of more communal trash bins, and the collection of waste by private contractors could help prevent exposing the public in municipalities to diseases. PMID:25005728
Domestic waste disposal practice and perceptions of private sector waste management in urban Accra.
Yoada, Ramatta Massa; Chirawurah, Dennis; Adongo, Philip Baba
2014-07-08
Waste poses a threat to public health and the environment if it is not stored, collected, and disposed of properly. The perception of waste as an unwanted material with no intrinsic value has dominated attitudes towards disposal. This study investigates the domestic waste practices, waste disposal, and perceptions about waste and health in an urban community. The study utilised a mixed-method approach. A cross-sectional survey questionnaire and in-depth interview were used to collect data. A total of 364 household heads were interviewed in the survey and six key informants were interviewed with the in-depth interviews. The results of the study revealed that 93.1% of households disposed of food debris as waste and 77.8% disposed of plastic materials as waste. The study also showed that 61.0% of the households disposed of their waste at community bins or had waste picked up at their homes by private contractors. The remaining 39.0% disposed of their waste in gutters, streets, holes and nearby bushes. Of those who paid for the services of private contractors, 62.9% were not satisfied with the services because of their cost and irregular collection. About 83% of the respondents were aware that improper waste management contributes to disease causation; most of the respondents thought that improper waste management could lead to malaria and diarrhoea. There was a general perception that children should be responsible for transporting waste from the households to dumping sites. Proper education of the public, the provision of more communal trash bins, and the collection of waste by private contractors could help prevent exposing the public in municipalities to diseases.
Unifying Terrain Awareness for the Visually Impaired through Real-Time Semantic Segmentation
Yang, Kailun; Wang, Kaiwei; Romera, Eduardo; Hu, Weijian; Sun, Dongming; Sun, Junwei; Cheng, Ruiqi; Chen, Tianxue; López, Elena
2018-01-01
Navigational assistance aims to help visually-impaired people to ambulate the environment safely and independently. This topic becomes challenging as it requires detecting a wide variety of scenes to provide higher level assistive awareness. Vision-based technologies with monocular detectors or depth sensors have sprung up within several years of research. These separate approaches have achieved remarkable results with relatively low processing time and have improved the mobility of impaired people to a large extent. However, running all detectors jointly increases the latency and burdens the computational resources. In this paper, we put forward seizing pixel-wise semantic segmentation to cover navigation-related perception needs in a unified way. This is critical not only for the terrain awareness regarding traversable areas, sidewalks, stairs and water hazards, but also for the avoidance of short-range obstacles, fast-approaching pedestrians and vehicles. The core of our unification proposal is a deep architecture, aimed at attaining efficient semantic understanding. We have integrated the approach in a wearable navigation system by incorporating robust depth segmentation. A comprehensive set of experiments prove the qualified accuracy over state-of-the-art methods while maintaining real-time speed. We also present a closed-loop field test involving real visually-impaired users, demonstrating the effectivity and versatility of the assistive framework. PMID:29748508
Imai, Hissei; Furukawa, Toshiaki A; Hayashi, Shin-U; Goto, Atsushi; Izumi, Kazuo; Hayashino, Yasuaki; Noda, Mitsuhiko
2018-03-01
We evaluated the associations of risk perception, self-efficacy, and trust with two health promotion behaviors (food habits and exercise) and depressive mood. Diabetic patients aged between 40 and 64 ( n = 1195) were included in the analyses. Risk perception worsened behavioral changes in terms of food habits and depression, whereas self-efficacy and trust improved food habits, exercise, and depression; trust improved exercise and depression. In conclusion, self-efficacy and trust appear to be more beneficial than risk perception for positive behavioral changes and for improving depression in diabetic patients. However, their influence on behavioral changes may be different according to the types of behaviors.
A Depth Map Generation Algorithm Based on Saliency Detection for 2D to 3D Conversion
NASA Astrophysics Data System (ADS)
Yang, Yizhong; Hu, Xionglou; Wu, Nengju; Wang, Pengfei; Xu, Dong; Rong, Shen
2017-09-01
In recent years, 3D movies attract people's attention more and more because of their immersive stereoscopic experience. However, 3D movies is still insufficient, so estimating depth information for 2D to 3D conversion from a video is more and more important. In this paper, we present a novel algorithm to estimate depth information from a video via scene classification algorithm. In order to obtain perceptually reliable depth information for viewers, the algorithm classifies them into three categories: landscape type, close-up type, linear perspective type firstly. Then we employ a specific algorithm to divide the landscape type image into many blocks, and assign depth value by similar relative height cue with the image. As to the close-up type image, a saliency-based method is adopted to enhance the foreground in the image and the method combine it with the global depth gradient to generate final depth map. By vanishing line detection, the calculated vanishing point which is regarded as the farthest point to the viewer is assigned with deepest depth value. According to the distance between the other points and the vanishing point, the entire image is assigned with corresponding depth value. Finally, depth image-based rendering is employed to generate stereoscopic virtual views after bilateral filter. Experiments show that the proposed algorithm can achieve realistic 3D effects and yield satisfactory results, while the perception scores of anaglyph images lie between 6.8 and 7.8.
Regulation and Mindful Resident Care in Nursing Homes
Colón-Emeric, Cathleen S.; Plowman, Donde; Bailey, Donald; Corazzini, Kirsten; Utley-Smith, Queen; Ammarell, Natalie; Toles, Mark; Anderson, Ruth
2009-01-01
Regulatory oversight is intended to improve the health outcomes of nursing home residents, yet evidence suggests that regulations can inhibit mindful staff behaviors that are associated with effective care. We explored the influence of regulations on mindful staff behavior as it relates to resident health outcomes, and offer a theoretical explanation of why regulations sometimes enhance mindfulness and other times inhibit it. We analyzed data from an in-depth, multiple case study including field notes, interviews, and documents collected in 8 nursing homes. We completed a conceptual/thematic description using the concept of mindfulness to reframe the observations. Shared facility mission strongly impacted staff perceptions of the purpose and utility of regulations. In facilities with a resident-centered culture, regulations increased mindful behavior, whereas in facilities with a cost-focused culture, regulations reduced mindful care practices. When managers emphasized the punitive aspects of regulation we observed a decrease in mindful practices in all facilities. PMID:20479137
Raju, M S; Rao, P S S
2011-01-01
As part of a community-based action research to reduce leprosy stigma, village committees were formed in 3 hyper endemic states of India. From a total of 10 village committees with nearly 200 members from Uttar Pradesh, a systematic random sample of 69 men and 23 women were interviewed in-depth regarding their views on sustainability of integrated leprosy services, as currently adopted. Their recommendations were also sought for further enhancement. Percentages were computed and compared for statistical significance using the z-normal test. The findings show that less than 50% of the respondents were confident that the present trend in voluntary early reporting for MDT and management of complications was adequate to sustain the integrated leprosy services. There were no differences by men or women members and they felt that lack of proper facilities, training and orientation of staff are most influencing factors. Many suggestions were given for improving the sustainability.
Discovering Self: Childbearing Adolescents' Maternal Identity.
Macintosh, Janelle; Callister, Lynn Clark
2015-01-01
Adolescent pregnancy and motherhood have long been a topic of interest for many healthcare professionals. However, there are limited data on how childbearing adolescents incorporate motherhood identity into their sense of self. The purpose of this study was to explore how childbearing adolescents perceive motherhood as becoming part of their personal identity. This qualitative study using ethnographic data collection involved 7 months of observation, interaction, and interviews. Data were collected from nine expectant adolescents during in-depth interviews. All participants were patients at a teen mother and child clinic staffed by certified nurse midwives and a pediatrician. Narrative content analysis revealed the overall theme of discovering self, with three major themes: confirming the pregnancy, the loss of my body, and imagining my child in my arms. Adolescent mothers may need assistance to construct their maternal identity in order to strengthen self-perceptions and improve maternal/child outcomes.
[Incentives to attract and retain the health workforce in rural areas of Peru: a qualitative study].
Huicho, Luis; Canseco, Francisco Díez; Lema, Claudia; Miranda, J Jaime; Lescano, Andrés G
2012-04-01
The study aimed to identify the main incentives for attracting and retaining health workers in rural and remote health facilities in Ayacucho, Peru. In-depth interviews were performed with 80 physicians, obstetricians, nurses, and nurse technicians in the poorest areas (20 per group), plus 11 health managers. Ayacucho lacks systematic policies for attracting and retaining human resources. The main incentives, in order of relevance, were higher wages, opportunities for further training, longer/permanent contracts, better infrastructure and medical equipment, and more staff. Interviewees also mentioned improved housing conditions and food, the opportunity to be closer to family, and recognition by the health system. Health workers and policymakers share perceptions on key incentives to encourage work in rural areas. However, there are also singularities to be considered when designing specific strategies. Public initiatives thus need to be monitored and evaluated closely in order to ensure the intended impact.
Analyzing task-based user study data to determine colormap efficiency
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ashton, Zoe Charon Maria; Wendelberger, Joanne Roth; Ticknor, Lawrence O.
2015-07-23
Domain scientists need colormaps to visualize their data and are especially useful for identifying areas of interest, like in ocean data to identify eddies or characterize currents. However, traditional Rainbow colormap performs poorly for understanding details, because of the small perceptual range. In order to assist domain scientists in recognizing and identifying important details in their data, different colormaps need to be applied to allow higher perceptual definition. Visual artist Francesca Samsel used her understanding of color theory to create new colormaps to improve perception. While domain scientists find the new colormaps to be useful, we implemented a rigorous andmore » quantitative study to determine whether or not the new colormaps have perceptually more colors. Color count data from one of these studies will be analyzed in depth in order to determine whether or not the new colormaps have more perceivable colors and what affects the number of perceivable colors.« less
Materials education activities
NASA Technical Reports Server (NTRS)
Ries, Heidi R.; Harris, Jonice; Leake, Woodrow W.; Bunnell, L. Roy; Berrettini, Robert
1993-01-01
Last year, at NEW: Update '91, a panel discussion was held to address the unique difficulties of attracting and retaining minorities and women in technical studies. Unfortunately, retention in technical majors is a problem of varying proportions for the entire student population, and must be improved in order to maintain the strength of the nation's industrial base. To investigate the cause of student attrition in technical majors, in-depth interviews of both current and former (non-graduating) engineering students at four colleges and universities in Colorado were conducted by Hewitt and Seymour. They found that there was no significant difference in the level of high school preparation and undergraduate academic performance in these two groups, despite the prevailing faculty perception that most students who switch from technical to nontechnical majors were underprepared. The majority of engineering students who changed majors reported that they were turned off by science, while one-third complained of poor teaching.
Robotic right middle lobectomy with a subxiphoid utility port.
Jayakumar, Shruti; Nardini, Marco; Papoulidis, Pavlos; Dunning, Joel
2018-06-01
We present the case of a 74-year-old man with Stage IIa pulmonary adenocarcinoma, for which he underwent a robotic right middle lobectomy. A 4-armed, 5-port approach was used. Four intercostal ports were created above the ninth rib using the Cerfolio's technique. The subxiphoid port was created in the midline, 5 cm down from the xiphisternum. The robot offers higher image quality, depth perception and improved articulation of the instruments, allowing for more accurate dissection and stitching. The usage of a subxiphoid utility port reduces the clashing between instruments, offers a good angle for stapling and provides a direct view of the instruments entering into the chest. Specimen removal through the subxiphoid port may reduce postoperative pain and enhance patient recovery. The use of the subxiphoid approach as a utility port for robotic surgery is promising and may be a suitable replacement for the traditional utility port.
Binocular summation for reflexive eye movements
Quaia, Christian; Optican, Lance M.; Cumming, Bruce G.
2018-01-01
Psychophysical studies and our own subjective experience suggest that, in natural viewing conditions (i.e., at medium to high contrasts), monocularly and binocularly viewed scenes appear very similar, with the exception of the improved depth perception provided by stereopsis. This phenomenon is usually described as a lack of binocular summation. We show here that there is an exception to this rule: Ocular following eye movements induced by the sudden motion of a large stimulus, which we recorded from three human subjects, are much larger when both eyes see the moving stimulus, than when only one eye does. We further discovered that this binocular advantage is a function of the interocular correlation between the two monocular images: It is maximal when they are identical, and reduced when the two eyes are presented with different images. This is possible only if the neurons that underlie ocular following are sensitive to binocular disparity. PMID:29621384
Between normality and deviance: the breakdown of batterers' identity following police intervention.
Buchbinder, Eli; Eisikovits, Zvi
2004-04-01
With the transformation of intimate violence from private trouble to social problem, police intervention in domestic violence cases became more prevalent. Research has focused mainly on battered women's perception of police intervention, their evaluations, and their level of satisfaction with the intervention. However, there is little research examining the perpetrators' subjective perceptions of such interventions. The purpose of this study is to describe and analyze battering men's perceptions of police intervention. The study is based on semistructured, in-depth interviews with 20 batterers who had repeated encounters with police. Findings show a continuum of self-management, ranging from attempts to preserve a normative identity in the first encounter to struggling against criminalization in the second encounter and adopting a victim identity in the third encounter. The findings are discussed in the context of gender identity and power relations.
Kim, Jooho; Ma, Jing; Almanza, Barbara
2017-06-01
The Food and Drug Administration recommended restaurant inspection scores change to a format that incorporated three new categories of violations: priority, priority foundation, and core. It was uncertain whether interested consumers would value the more in-depth information or become more confused. The purpose of this study was to assess consumer perception of the recommended inspection system. Data were collected from an online survey. Results showed that consumers want convenient access to the information either online or on the wall of restaurants, and some consumers do want to read inspection reports and use them in making dining decisions. Choice of restaurant inspection format did appear to change consumer understanding and perceptions about some of the violations. Results also demonstrated the importance of the words used to categorize violations.