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 ...

Acute aerobic exercise differentially alters acylated ghrelin and perceived fullness in normal-weight and obese individuals.

PubMed

Heden, Timothy D; Liu, Ying; Park, Youngmin; Dellsperger, Kevin C; Kanaley, Jill A

2013-09-01

Adiposity alters acylated ghrelin concentrations, but it is unknown whether adiposity alters the effect of exercise and feeding on acylated ghrelin responses. Therefore, the purpose of this study was to determine whether adiposity [normal-weight (NW) vs. obese (Ob)] influences the effect of exercise and feeding on acylated ghrelin, hunger, and fullness. Fourteen NW and 14 Ob individuals completed two trials in a randomized counterbalanced fashion, including a prior exercise trial (EX) and a no exercise trial (NoEX). During the EX trial, the participants performed 1 h of treadmill walking (55-60% peak O2 uptake) during the evening, 12 h before a 4-h standardized mixed meal test. Frequent blood samples were taken and analyzed for acylated ghrelin, and a visual analog scale was used to assess perceived hunger and fullness. In NW individuals, EX, compared with NoEX, reduced fasting acylated ghrelin concentrations by 18% (P = 0.03), and, in response to feeding, the change in acylated ghrelin (P = 0.02) was attenuated by 39%, but perceived hunger and fullness were unaltered. In Ob individuals, despite no changes in fasting or postprandial acylated ghrelin concentrations with EX, postprandial fullness was attenuated by 46% compared with NoEX (P = 0.05). In summary, exercise performed the night before a meal suppresses acylated ghrelin concentrations in NW individuals without altering perceived hunger or fullness. In Ob individuals, despite no changes in acylated ghrelin concentrations, EX reduced the fullness response to the test meal. Acylated ghrelin and perceived fullness responses are differently altered by acute aerobic exercise in NW and Ob individuals.

The Role of the Environment in Eliciting Phantom-Like Sensations in Non-Amputees

PubMed Central

Lewis, Elizabeth; Lloyd, Donna M.; Farrell, Martin J.

2013-01-01

Following the amputation of a limb, many amputees report that they can still vividly perceive its presence despite conscious knowledge that it is not physically there. However, our ability to probe the mental representation of this experience is limited by the intractable and often distressing pain associated with amputation. Here, we present a method for eliciting phantom-like experiences in non-amputees using a variation of the rubber hand illusion in which a finger has been removed from the rubber hand. An interpretative phenomenological analysis revealed that the structure of this experience shares a wide range of sensory attributes with subjective reports of phantom limb experience. For example, when the space where the ring finger should have been on the rubber hand was stroked, 93% of participants (i.e., 28/30) reported the vivid presence of a finger that they could not see and a total of 57% (16/28) of participants who felt that the finger was present reported one or more additional sensory qualities such as tingling or numbness (25%; 7/28) and alteration in the perceived size of the finger (50%; 14/28). These experiences indicate the adaptability of body experience and share some characteristics of the way that phantom limbs are described. Participants attributed changes to the shape and size of their “missing” finger to the way in which the experimenter mimed stroking in the area occupied by the missing finger. This alteration of body perception is similar to the phenomenon of telescoping experienced by people with phantom limbs and suggests that our sense of embodiment not only depends on internal body representations but on perceptual information coming from peripersonal space. PMID:23355829

Obesity Bias in Children: The Role of Actual and Perceived Body Size

ERIC Educational Resources Information Center

Kornilaki, Ekaterina N.

2015-01-01

The aim of this study was to examine how children perceive their body size and whether their actual or perceived body size can explain their anti-fat views. Four hundred and fourteen 5-6, 7-8 and 9-10-year-old children were read short vignettes depicting two characters, one possessing a positive and the other a negative quality. Following each…

Garment sizes in perception of body size.

PubMed

Fan, Jintu; Newton, Edward; Lau, Lilian; Liu, Fu

2003-06-01

This paper reports an experimental investigation of the effect of garment size on perceived body size. The perceived body sizes of three Chinese men (thin, medium, and obese build) wearing different sizes of white T-shirts were assessed using Thompson and Gray's 1995 Nine-figural Scale in 1 (thinnest) to 9 (obese) grade and a newly-proposed method. Within the limit of commercially available T-shirt sizes, for thin and medium persons, perceived body sizes are bigger when wearing T-shirts of larger sizes. For an obese person, however, wearing a large size T-shirt tends to make him look thinner. The study also showed that the newly proposed comparative method is more reliable in comparing body size perception but without measuring the magnitude of the change in body-size grade. The figural scale and the comparative method can be complementary.

Illusory Distance Modulates Perceived Size of Afterimage despite the Disappearance of Depth Cues

PubMed Central

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

It’s Out of My Hands! Grasping Capacity May Not Influence Perceived Object Size

PubMed Central

2017-01-01

Linkenauger, Witt, and Proffitt (2011) found that the perceived size of graspable objects was scaled by perceived grasping capacity. However, it is possible that this effect occurred because object size was estimated on the same trial as grasping capacity. This may have led to a conflation of estimates of perceived action capacity and spatial properties. In 5 experiments, we tested Linkenauger et al.’s claim that right-handed observers overestimate the grasping capacity of their right hand relative to their left hand, and that this, in turn, leads them to underestimate the size of objects to-be-grasped in their right hand relative to their left hand. We replicated the finding that right handers overestimate the size and grasping capacity of their right hand relative to their left hand. However, when estimates of object size and grasping capacity were made in separate tasks, objects grasped in the right hand were not underestimated relative to those grasped in the left hand. Further, when grasping capacity was physically restricted, observers appropriately recalibrated their perception of their maximum grasp but estimates of object size were unaffected. Our results suggest that changes in action capacity may not influence perceived object size if sources of conflation are controlled for. PMID:28191987

Ideal Body Size as a Mediator for the Gender-Specific Association Between Socioeconomic Status and Body Mass Index: Evidence From an Upper-Middle-Income Country in the African Region.

PubMed

Yepes, Maryam; Maurer, Jürgen; Stringhini, Silvia; Viswanathan, Barathi; Gedeon, Jude; Bovet, Pascal

2016-04-01

While obesity continues to rise globally, the associations between body size, gender, and socioeconomic status (SES) seem to vary in different populations, and little is known on the contribution of perceived ideal body size in the social disparity of obesity in African countries. We examined the gender and socioeconomic patterns of body mass index (BMI) and perceived ideal body size in the Seychelles, a middle-income small island state in the African region. We also assessed the potential role of perceived ideal body size as a mediator for the gender-specific association between SES and BMI. A population-based survey of 1,240 adults aged 25 to 64 years conducted in December 2013. Participants' BMI was calculated based on measured weight and height; ideal body size was assessed using a nine-silhouette instrument. Three SES indicators were considered: income, education, and occupation. BMI and perceived ideal body size were both higher among men of higher versus lower SES (p< .001) but lower among women of higher versus lower SES (p< .001), irrespective of the SES indicator used. Multivariate analysis showed a strong and direct association between perceived ideal body size and BMI in both men and women (p< .001) and was consistent with a potential mediating role of perceived ideal body size in the gender-specific associations between SES and BMI. Our study emphasizes the importance of gender and socioeconomic differences in BMI and ideal body size and suggests that public health interventions that promote perception of healthy weight could help mitigate SES-related disparities in BMI. © 2016 Society for Public Health Education.

The Effect of a Web Seal's Placement, Color, and Size, and the E-Retailer's Name on Intention to Purchase Online as Mediated by Perceived Trust and Perceived Risk

ERIC Educational Resources Information Center

Stewart, Roy

2012-01-01

This study investigates the effects of the e-retailer's "Website Name," and a third party assurance seal's position, color, and size on "Intention to Purchase Online". Since "Intention to Purchase Online" is influenced by both "Perceived Trust" and "Perceived Risk," and since…

The influence of varying maxillary incisal edge embrasure space and interproximal contact area dimensions on perceived smile aesthetics.

PubMed

Foulger, T E; Tredwin, C J; Gill, D S; Moles, D R

2010-08-14

The aim of this study was to determine the influence of incisal edge embrasure space and interproximal contact area dimensions on perceived smile aesthetics. Cross-sectional study. Postgraduate dental teaching hospital. A photograph of a smiling female, displaying only the lips and maxillary teeth was digitally altered. First, the proportions of the incisal edge embrasure spaces were modified to produce five different images. Secondly, the lengths of the interproximal contact areas were altered to produce five different images. The two sets of photographs were ranked from 'most attractive' to 'least attractive' by 35 dentists, 35 dental technicians and 35 patients. An embrasure space arrangement where the size of the embrasures increases progressively distally from the midline was deemed most attractive; absence of embrasure spaces was deemed least attractive. In assessing the interproximal contact areas, all groups assessed an arrangement where the areas between the teeth were equal (and 50% the length of the central incisor) as most attractive, and where the contact areas increased in length progressively distally from the midline as least attractive. There were few statistically significant differences between the groups in these perceptions. Whilst there is broad agreement in what the participant groups deem to be aesthetic, our findings do not wholly correspond to the 'ideals' that have been previously suggested in the dental literature.

Is portion size selection associated with expected satiation, perceived healthfulness or expected tastiness? A case study on pizza using a photograph-based computer task.

PubMed

Labbe, D; Rytz, A; Godinot, N; Ferrage, A; Martin, N

2017-01-01

Increasing portion sizes over the last 30 years are considered to be one of the factors underlying overconsumption. Past research on the drivers of portion selection for foods showed that larger portions are selected for foods delivering low expected satiation. However, the respective contribution of expected satiation vs. two other potential drivers of portion size selection, i.e. perceived healthfulness and expected tastiness, has never been explored. In this study, we conjointly explored the role of expected satiation, perceived healthfulness and expected tastiness when selecting portions within a range of six commercial pizzas varying in their toppings and brands. For each product, 63 pizza consumers selected a portion size that would satisfy them for lunch and scored their expected satiation, perceived healthfulness and expected tastiness. As six participants selected an entire pizza as ideal portion independently of topping or brand, their data sets were not considered in the data analyses completed on responses from 57 participants. Hierarchical multiple regression analyses showed that portion size variance was predicted by perceived healthiness and expected tastiness variables. Two sub-groups of participants with different portion size patterns across pizzas were identified through post-hoc exploratory analysis. The explanatory power of the regression model was significantly improved by adding interaction terms between sub-group and expected satiation variables and between sub-group and perceived healthfulness variables to the model. Analysis at a sub-group level showed either positive or negative association between portion size and expected satiation depending on sub-groups. For one group, portion size selection was more health-driven and for the other, more hedonic-driven. These results showed that even when considering a well-liked product category, perceived healthfulness can be an important factor influencing portion size decision. Copyright © 2016 Nestec S.A. Published by Elsevier Ltd.. All rights reserved.

Perceived depth between familiar objects.

DOT National Transportation Integrated Search

1967-08-01

In aviation, size cues are frequently used in a pilot's evaluation of depth or distance. In the study, the hypothesis was examined that the essential factor in the size cue to depth from familiar objects is the perceived size S' per unit of retinal s...

Form features provide a cue to the angular velocity of rotating objects

PubMed Central

Blair, Christopher David; Goold, Jessica; Killebrew, Kyle; Caplovitz, Gideon Paul

2013-01-01

As an object rotates, each location on the object moves with an instantaneous linear velocity dependent upon its distance from the center of rotation, while the object as a whole rotates with a fixed angular velocity. Does the perceived rotational speed of an object correspond to its angular velocity, linear velocities, or some combination of the two? We had observers perform relative speed judgments of different sized objects, as changing the size of an object changes the linear velocity of each location on the object’s surface, while maintaining the object’s angular velocity. We found that the larger a given object is, the faster it is perceived to rotate. However, the observed relationships between size and perceived speed cannot be accounted for simply by size-related changes in linear velocity. Further, the degree to which size influences perceived rotational speed depends on the shape of the object. Specifically, perceived rotational speeds of objects with corners or regions of high contour curvature were less affected by size. The results suggest distinct contour features, such as corners or regions of high or discontinuous contour curvature, provide cues to the angular velocity of a rotating object. PMID:23750970

Form features provide a cue to the angular velocity of rotating objects.

PubMed

Blair, Christopher David; Goold, Jessica; Killebrew, Kyle; Caplovitz, Gideon Paul

2014-02-01

As an object rotates, each location on the object moves with an instantaneous linear velocity, dependent upon its distance from the center of rotation, whereas the object as a whole rotates with a fixed angular velocity. Does the perceived rotational speed of an object correspond to its angular velocity, linear velocities, or some combination of the two? We had observers perform relative speed judgments of different-sized objects, as changing the size of an object changes the linear velocity of each location on the object's surface, while maintaining the object's angular velocity. We found that the larger a given object is, the faster it is perceived to rotate. However, the observed relationships between size and perceived speed cannot be accounted for simply by size-related changes in linear velocity. Further, the degree to which size influences perceived rotational speed depends on the shape of the object. Specifically, perceived rotational speeds of objects with corners or regions of high-contour curvature were less affected by size. The results suggest distinct contour features, such as corners or regions of high or discontinuous contour curvature, provide cues to the angular velocity of a rotating object. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Perceived face size in healthy adults.

PubMed

D'Amour, Sarah; Harris, Laurence R

2017-01-01

Perceptual body size distortions have traditionally been studied using subjective, qualitative measures that assess only one type of body representation-the conscious body image. Previous research on perceived body size has typically focused on measuring distortions of the entire body and has tended to overlook the face. Here, we present a novel psychophysical method for determining perceived body size that taps into implicit body representation. Using a two-alternative forced choice (2AFC), participants were sequentially shown two life-size images of their own face, viewed upright, upside down, or tilted 90°. In one interval, the width or length dimension was varied, while the other interval contained an undistorted image. Participants reported which image most closely matched their own face. An adaptive staircase adjusted the distorted image to hone in on the image that was equally likely to be judged as matching their perceived face as the accurate image. When viewed upright or upside down, face width was overestimated and length underestimated, whereas perception was accurate for the on-side views. These results provide the first psychophysically robust measurements of how accurately healthy participants perceive the size of their face, revealing distortions of the implicit body representation independent of the conscious body image.

The role of retinal versus perceived size in the effects of pitched displays on visually perceived eye level

NASA Technical Reports Server (NTRS)

Post, R. B.; Welch, R. B.

1996-01-01

Visually perceived eye level (VPEL) was measured while subjects viewed two vertical lines which were either upright or pitched about the horizontal axis. In separate conditions, the display consisted of a relatively large pair of lines viewed at a distance of 1 m, or a display scaled to one third the dimensions and viewed at a distance of either 1 m or 33.3 cm. The small display viewed at 33.3 cm produced a retinal image the same size as that of the large display at 1 m. Pitch of all three displays top-toward and top-away from the observer caused upward and downward VPEL shifts, respectively. These effects were highly similar for the large display and the small display viewed at 33.3 cm (ie equal retinal size), but were significantly smaller for the small display viewed at 1 m. In a second experiment, perceived size of the three displays was measured and found to be highly accurate. The results of the two experiments indicate that the effect of optical pitch on VPEL depends on the retinal image size of stimuli rather than on perceived size.

Perspective Space as a Model for Distance and Size Perception.

PubMed

Erkelens, Casper J

2017-01-01

In the literature, perspective space has been introduced as a model of visual space. Perspective space is grounded on the perspective nature of visual space during both binocular and monocular vision. A single parameter, that is, the distance of the vanishing point, transforms the geometry of physical space into that of perspective space. The perspective-space model predicts perceived angles, distances, and sizes. The model is compared with other models for distance and size perception. Perspective space predicts that perceived distance and size as a function of physical distance are described by hyperbolic functions. Alternatively, power functions have been widely used to describe perceived distance and size. Comparison of power and hyperbolic functions shows that both functions are equivalent within the range of distances that have been judged in experiments. Two models describing perceived distance on the ground plane appear to be equivalent with the perspective-space model too. The conclusion is that perspective space unifies a number of models of distance and size perception.

Perspective Space as a Model for Distance and Size Perception

PubMed Central

2017-01-01

In the literature, perspective space has been introduced as a model of visual space. Perspective space is grounded on the perspective nature of visual space during both binocular and monocular vision. A single parameter, that is, the distance of the vanishing point, transforms the geometry of physical space into that of perspective space. The perspective-space model predicts perceived angles, distances, and sizes. The model is compared with other models for distance and size perception. Perspective space predicts that perceived distance and size as a function of physical distance are described by hyperbolic functions. Alternatively, power functions have been widely used to describe perceived distance and size. Comparison of power and hyperbolic functions shows that both functions are equivalent within the range of distances that have been judged in experiments. Two models describing perceived distance on the ground plane appear to be equivalent with the perspective-space model too. The conclusion is that perspective space unifies a number of models of distance and size perception. PMID:29225765

Visual illusions and plate design: the effects of plate rim widths and rim coloring on perceived food portion size.

PubMed

McClain, A D; van den Bos, W; Matheson, D; Desai, M; McClure, S M; Robinson, T N

2014-05-01

The Delboeuf Illusion affects perceptions of the relative sizes of concentric shapes. This study was designed to extend research on the application of the Delboeuf illusion to food on a plate by testing whether a plate's rim width and coloring influence perceptual bias to affect perceived food portion size. Within-subjects experimental design. Experiment 1 tested the effect of rim width on perceived food portion size. Experiment 2 tested the effect of rim coloring on perceived food portion size. In both experiments, participants observed a series of photographic images of paired, side-by-side plates varying in designs and amounts of food. From each pair, participants were asked to select the plate that contained more food. Multilevel logistic regression examined the effects of rim width and coloring on perceived food portion size. Experiment 1: participants overestimated the diameter of food portions by 5% and the visual area of food portions by 10% on plates with wider rims compared with plates with very thin rims (P<0.0001). The effect of rim width was greater with larger food portion sizes. Experiment 2: participants overestimated the diameter of food portions by 1.5% and the visual area of food portions by 3% on plates with rim coloring compared with plates with no coloring (P=0.01). The effect of rim coloring was greater with smaller food portion sizes. The Delboeuf illusion applies to food on a plate. Participants overestimated food portion size on plates with wider and colored rims. These findings may help design plates to influence perceptions of food portion sizes.

Investigating Young Children's Perceptions of Body Size and Healthy Habits

ERIC Educational Resources Information Center

Xu, Tingting; Nerren, Jannah S.

2017-01-01

Attitudes and biases toward body size perceived as fat and body size perceived as thin are present in young children (Cramer and Steinwert in "J Appl Dev Psychol" 19(3):429-451, 1998; Worobey and Worobey in "Body Image" 11:171-174, 2014). However, the information children have regarding body size and ways to modify body size…

The moon illusion: a different view through the legs.

PubMed

Coren, S

1992-12-01

The fact that the overestimation of the horizon moon is reduced when individuals bend over and view it through their legs has been used as support for theories of the moon illusion based upon angle of regard and vestibular inputs. Inversion of the visual scene, however, can also reduce the salience of depth cue, so illusion reduction might be consistent with size constancy explanations. A sample of 70 subjects viewed normal and inverted pictorial arrays. The moon illusion was reduced in the inverted arrays, suggesting that the "through the legs" reduction of the moon illusion may reflect the alteration in perceived depth associated with scene inversion rather than angle of regard or vestibular effects.

Changes in the distribution of sustained attention alter the perceived structure of visual space.

PubMed

Fortenbaugh, Francesca C; Robertson, Lynn C; Esterman, Michael

2017-02-01

Visual spatial attention is a critical process that allows for the selection and enhanced processing of relevant objects and locations. While studies have shown attentional modulations of perceived location and the representation of distance information across multiple objects, there remains disagreement regarding what influence spatial attention has on the underlying structure of visual space. The present study utilized a method of magnitude estimation in which participants must judge the location of briefly presented targets within the boundaries of their individual visual fields in the absence of any other objects or boundaries. Spatial uncertainty of target locations was used to assess perceived locations across distributed and focused attention conditions without the use of external stimuli, such as visual cues. Across two experiments we tested locations along the cardinal and 45° oblique axes. We demonstrate that focusing attention within a region of space can expand the perceived size of visual space; even in cases where doing so makes performance less accurate. Moreover, the results of the present studies show that when fixation is actively maintained, focusing attention along a visual axis leads to an asymmetrical stretching of visual space that is predominantly focused across the central half of the visual field, consistent with an expansive gradient along the focus of voluntary attention. These results demonstrate that focusing sustained attention peripherally during active fixation leads to an asymmetrical expansion of visual space within the central visual field. Published by Elsevier Ltd.

Maternal body condition influences magnitude of anti-predator response in offspring.

PubMed

Bennett, Amanda M; Murray, Dennis L

2014-11-07

Organisms exhibit plasticity in response to their environment, but there is large variation even within populations in the expression and magnitude of response. Maternal influence alters offspring survival through size advantages in growth and development. However, the relationship between maternal influence and variation in plasticity in response to predation risk is unknown. We hypothesized that variation in the magnitude of plastic responses between families is at least partly due to maternal provisioning and examined the relationship between maternal condition, egg provisioning and magnitude of plastic response to perceived predation risk (by dragonfly larvae: Aeshna spp.) in northern leopard frogs (Lithobates pipiens). Females in better body condition tended to lay more (clutch size) larger (egg diameter) eggs. Tadpoles responded to predation risk by increasing relative tail depth (morphology) and decreasing activity (behaviour). We found a positive relationship between morphological effect size and maternal condition, but no relationship between behavioural effect size and maternal condition. These novel findings suggest that limitations imposed by maternal condition can constrain phenotypic variation, ultimately influencing the capacity of populations to respond to environmental change. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Verification of Emmert's law in actual and virtual environments.

PubMed

Nakamizo, Sachio; Imamura, Mariko

2004-11-01

We examined Emmert's law by measuring the perceived size of an afterimage and the perceived distance of the surface on which the afterimage was projected in actual and virtual environments. The actual environment consisted of a corridor with ample cues as to distance and depth. The virtual environment was made from the CAVE of a virtual reality system. The afterimage, disc-shaped and one degree in diameter, was produced by flashing with an electric photoflash. The observers were asked to estimate the perceived distance to surfaces located at various physical distances (1 to 24 m) by the magnitude estimation method and to estimate the perceived size of the afterimage projected on the surfaces by a matching method. The results show that the perceived size of the afterimage was directly proportional to the perceived distance in both environments; thus, Emmert's law holds in virtual as well as actual environments. We suggest that Emmert's law is a specific case of a functional principle of distance scaling by the visual system.

Visual illusions and plate design: The effects of plate rim widths and rim coloring on perceived food portion size

PubMed Central

McClain, Arianna; van den Bos, Wouter; Matheson, Donna; Desai, Manisha; McClure, Samuel M.; Robinson, Thomas N.

2013-01-01

OBJECTIVE The Delboeuf Illusion affects perceptions of the relative sizes of concentric shapes. This study was designed to extend research on the application of the Delboeuf illusion to food on a plate by testing whether a plate’s rim width and coloring influence perceptual bias to affect perceived food portion size. DESIGN AND METHODS Within-subjects experimental design. Experiment 1 tested the effect of rim width on perceived food portion size. Experiment 2 tested the effect of rim coloring on perceived food portion size. In both experiments, participants observed a series of photographic images of paired, side-by-side plates varying in designs and amounts of food. From each pair, participants were asked to select the plate that contained more food. Multi-level logistic regression examined the effects of rim width and coloring on perceived food portion size. RESULTS Experiment 1: Participants overestimated the diameter of food portions by 5% and the visual area of food portions by 10% on plates with wider rims compared to plates with very thin rims (P<0.0001). The effect of rim width was greater with larger food portion sizes. Experiment 2: Participants overestimated the diameter of food portions by 1.5% and the visual area of food portions by 3% on plates with rim coloring compared to plates with no coloring (P=0.01). The effect of rim coloring was greater with smaller food portion sizes. CONCLUSION The Delboeuf illusion applies to food on a plate. Participants overestimated food portion size on plates with wider and colored rims. These findings may help design plates to influence perceptions of food portion sizes. PMID:24005858

A blind human expert echolocator shows size constancy for objects perceived by echoes.

PubMed

Milne, Jennifer L; Anello, Mimma; Goodale, Melvyn A; Thaler, Lore

2015-01-01

Some blind humans make clicking noises with their mouth and use the reflected echoes to perceive objects and surfaces. This technique can operate as a crude substitute for vision, allowing human echolocators to perceive silent, distal objects. Here, we tested if echolocation would, like vision, show size constancy. To investigate this, we asked a blind expert echolocator (EE) to echolocate objects of different physical sizes presented at different distances. The EE consistently identified the true physical size of the objects independent of distance. In contrast, blind and blindfolded sighted controls did not show size constancy, even when encouraged to use mouth clicks, claps, or other signals. These findings suggest that size constancy is not a purely visual phenomenon, but that it can operate via an auditory-based substitute for vision, such as human echolocation.

The natural moon illusion: a multifactor angular account.

PubMed

Plug, C; Ross, H E

1994-01-01

It is argued that the failure to explain the celestial illusion results from conceptual confusion about perceived size and from disregard of the observational evidence relating to the natural moon illusion. The evidence shows that the illusion consists of a perceived angular size enlargement of horizon objects, by a factor of about 1.5-2.0 in diameter in comparison with elevated objects. Most measurements of the illusion have been made in terms of angular size, although in some proposed explanations an illusion of linear size is assumed. The magnitude of the illusion varies, particularly with the detail of the horizon scene. The illusion can be explained as the sum of several factors that affect perceived angular size: size contrast, vergence commands and eye or head position, aerial perspective, and colour. The relative contributions of these factors are assessed.

The role of perceived stress and gender on portion selection patterns.

PubMed

Lim, E X; Sim, A Y; Forde, C G; Cheon, B K

2018-06-01

Stress is linked to increased preferences and consumption of palatable energy dense foods, particularly among females. Despite the role of stress on potentially obesogenic eating habits, its effect on pre-meal planning, such as the selection of portion sizes, remain unknown. Here, we investigated the relationship between perceived stress, gender, and intended portion sizes for diverse foods. Across two studies, increased perceived stress predicted larger (higher energy) intended portion sizes across a variety of food items among females, but not males. Additionally, for females, increased perceived stress was associated with lowered expectations of the satiety of foods presented, suggesting a potential mechanism by which stress may influence decisions about portion size. These findings reveal that the potentially obesogenic effects of stress on food judgments and behaviours (particularly among females) are not only expressed within meals, but also during more deliberate stages of planning that precedes meals. Copyright © 2018 Elsevier Inc. All rights reserved.

The paradoxical moon illusions.

PubMed

Gilinsky, A S

1980-02-01

An adaptation theory of visual space is developed and applied to the data of a variety of studies of visual space perception. By distinguishing between the perceived distance of an object and that of the background or sky, the theory resolves the paradox of the moon illusions and relates both perceived size and perceived distance of the moon to the absolute level of spatial adaptation. The theory assumes that visual space expands or contracts in adjustment to changes in the sensory indicators of depth and provides a measure, A, of this adaptation-level. Changes in A have two effects--one on perceived size, one on perceived distance. Since A varies systematically as a function of angle of regard, availability of cues, and the total space-value, A is a measure of the moon illusions, and a practical index of individual differences by pilots and astronauts in the perception of the size and distance of objects on the ground and in the air.

The effects of gap size and disturbance type on invasion of wet pine savanna by cogongrass, Imperata cylindrica (Poaceae)

USGS Publications Warehouse

King, S.E.; Grace, J.B.

2000-01-01

Cogongrass is a nonindigenous species perceived to threaten native communities of the southeastern United States through modification of species composition and alteration of community processes. To examine how gap size and disturbance type influence the invasion of wet pine savannas by cogongrass, we performed three field experiments to evaluate the response of cogongrass seeds and transplanted seedlings to four different gap sizes, four types of site disturbance, and recent burning of savanna vegetation. Cogongrass germinated, survived, and grew in all gap sizes, from 0 to 100 cm in diameter. Similarly, disturbance type had no effect on germination or seedling and transplant survival. Tilling, however, significantly enhanced transplanted seedling growth, resulting in a tenfold increase in biomass over the other disturbance types. Seedling survival to 1 and 2 mo was greater in burned savanna than unburned savanna, although transplant survival and growth were not affected by burning. Results of this study suggest that cogongrass can germinate, survive, and grow in wet pine savanna communities regardless of gap size or type of disturbance, including burning. Burning of savanna vegetation may enhance establishment by improving early seedling survival, and soil disturbance can facilitate invasion of cogongrass by enhancing plant growth.

The effects of gap size and disturbance type on invasion of wet pine savanna by cogongrass, Imperata cylindrica (Poaceae).

PubMed

King, S E; Grace, J B

2000-09-01

Cogongrass is a nonindigenous species perceived to threaten native communities of the southeastern United States through modification of species composition and alteration of community processes. To examine how gap size and disturbance type influence the invasion of wet pine savannas by cogongrass, we performed three field experiments to evaluate the response of cogongrass seeds and transplanted seedlings to four different gap sizes, four types of site disturbance, and recent burning of savanna vegetation. Cogongrass germinated, survived, and grew in all gap sizes, from 0 to 100 cm in diameter. Similarly, disturbance type had no effect on germination or seedling and transplant survival. Tilling, however, significantly enhanced transplanted seedling growth, resulting in a tenfold increase in biomass over the other disturbance types. Seedling survival to 1 and 2 mo was greater in burned savanna than unburned savanna, although transplant survival and growth were not affected by burning. Results of this study suggest that cogongrass can germinate, survive, and grow in wet pine savanna communities regardless of gap size or type of disturbance, including burning. Burning of savanna vegetation may enhance establishment by improving early seedling survival, and soil disturbance can facilitate invasion of cogongrass by enhancing plant growth.

Size Matters: The Link between Staff Size and Perceived Organizational Support in Early Childhood Education

ERIC Educational Resources Information Center

Ho, Dora; Lee, Moosung; Teng, Yue

2016-01-01

Purpose: The purpose of this paper is to examine the relationship between staff size and perceived organizational support (POS) in early childhood education (ECE) organizations. Design/methodology/approach: A territory-wide questionnaire survey was designed to investigate the perceptions of preschool teachers in Hong Kong on four dimensions of…

Weber's Illusion and Body Shape: Anisotropy of Tactile Size Perception on the Hand

ERIC Educational Resources Information Center

Longo, Matthew R.; Haggard, Patrick

2011-01-01

The perceived distance between touches on a single skin surface is larger on regions of high tactile sensitivity than those with lower acuity, an effect known as "Weber's illusion". This illusion suggests that tactile size perception involves a representation of the perceived size of body parts preserving characteristics of the somatosensory…

Attention changes perceived size of moving visual patterns.

PubMed

Anton-Erxleben, Katharina; Henrich, Christian; Treue, Stefan

2007-08-23

Spatial attention shifts receptive fields in monkey extrastriate visual cortex toward the focus of attention (S. Ben Hamed, J. R. Duhamel, F. Bremmer, & W. Graf, 2002; C. E. Connor, J. L. Gallant, D. C. Preddie, & D. C. Van Essen, 1996; C. E. Connor, D. C. Preddie, J. L. Gallant, & D. C. Van Essen, 1997; T. Womelsdorf, K. Anton-Erxleben, F. Pieper, & S. Treue, 2006). This distortion in the retinotopic distribution of receptive fields might cause distortions in spatial perception such as an increase of the perceived size of attended stimuli. Here we test for such an effect in human subjects by measuring the point of subjective equality (PSE) for the perceived size of a neutral and an attended stimulus when drawing automatic attention to one of two spatial locations. We found a significant increase in perceived size of attended stimuli. Depending on the absolute stimulus size, this effect ranged from 4% to 12% and was more pronounced for smaller than for larger stimuli. In our experimental design, an attentional effect on task difficulty or a cue bias might influence the PSE measure. We performed control experiments and indeed found such effects, but they could only account for part of the observed results. Our findings demonstrate that the allocation of transient spatial attention onto a visual stimulus increases its perceived size and additionally biases subjects to select this stimulus for a perceptual judgment.

Relationship between perceived body image and recorded body mass index among Kuwaiti female university students.

PubMed

Kabir, Yearul; Zafar, Tasleem A; Waslien, Carol

2013-01-01

The associations between body image and attitudes toward obesity and thinness and their associations with measured body mass index (BMI) among female students of Kuwait University (n = 137) was examined in 2008. The body image perceptions were assessed using nine female silhouettes figures. The difference between current perceived body image (PBI) and ideal body image (IBI) was used as a measure of body image dissatisfaction (BID). Students tended to have a bigger PBI and smaller IBI than would be expected from their BMI category, leading to high levels of BID in each BMI category. PBI, IBI, BID, RBI were highly correlated with each other, and BMI was significantly correlated with each of them. The coefficients of these associations were not significantly altered in multiple regression analysis by the addition of potential confounding variables, such as age, marital status, physical activity, dieting behavior, parental education, and family size. These results suggest that PBI and a desire to be thinner were strongly related to BID and that thinness is becoming more desired in Kuwaiti society than the plump body image of the past.

Does apparent size capture attention in visual search? Evidence from the Muller-Lyer illusion.

PubMed

Proulx, Michael J; Green, Monique

2011-11-23

Is perceived size a crucial factor for the bottom-up guidance of attention? Here, a visual search experiment was used to examine whether an irrelevantly longer object can capture attention when participants were to detect a vertical target item. The longer object was created by an apparent size manipulation, the Müller-Lyer illusion; however, all objects contained the same number of pixels. The vertical target was detected more efficiently when it was also perceived as the longer item that was defined by apparent size. Further analysis revealed that the longer Müller-Lyer object received a greater degree of attentional priority than published results for other features such as retinal size, luminance contrast, and the abrupt onset of a new object. The present experiment has demonstrated for the first time that apparent size can capture attention and, thus, provide bottom-up guidance on the basis of perceived salience.

Big Money: The Effect of Money Size on Value Perceptions and Saving Motivation.

PubMed

Peetz, Johanna; Soliman, Monica

2016-01-28

Motivated perception has been shown to affect people's estimates of money (e.g., perceiving coins as larger than real size). In the present research, we examine whether simply varying the size of a picture of money can affect its perceived value and subsequent decisions. Participants presented with a picture of money enlarged by 15% perceived the depicted money as more valuable compared with those seeing a real-size picture (Study 1). When told to imagine their own cash and banked money in the depicted form, participants presented with a picture enlarged by 15% felt more subjectively wealthy and reported fewer intentions to conserve their money compared with those seeing a real-size picture of the same money (Study 2). Together, these studies suggest that judgments about money and even attitudes toward personal spending can be influenced by manipulating the size of a picture of money. © The Author(s) 2016.

Psychosocial risks in small enterprises: The mediating role of perceived working conditions in the relationship between enterprise size and workers' anxious or depressive episodes.

PubMed

Encrenaz, Gaëlle; Laberon, Sonia; Lagabrielle, Christine; Debruyne, Gautier; Pouyaud, Jacques; Rascle, Nicole

2018-03-20

The relationship between enterprise size and psychosocial working conditions has received little attention so far but some findings suggest that they are more favorable in small enterprises. This could have a positive impact on workers' mental health. The objective of this study was to test the mediating effect of perceived working conditions in the relationship between enterprise size and anxious or depressive episodes. Data from the 2010 SUMER French periodical cross-sectional survey was analyzed (N=31 420 for the present study). Anxious or depressive episodes were measured with the hospital anxiety and depression scale (HAD) and perceived working conditions were psychological demand, decision latitude and social support as assessed with Karasek's job content questionnaire (JCQ). The indirect effect was tested according to the method proposed by Preacher and Hayes (2008). In a multivariate logistic regression, the risk of anxious or depressive episodes was found to be lower in micro-enterprises (2-9 employees). Formal tests pointed to a significant indirect effect of enterprise size on mental health through perceived working conditions, with a larger effect for psychological demand. Conclusion This study highlights perceived working conditions as an explanation of the effects of enterprise size.

Does Flattened Sky Dome Reduces Perceived Moon Size

NASA Astrophysics Data System (ADS)

Toskovic, O.

2009-09-01

The aim of this study was to examine the Flattened sky dome model as an explanation of the Moon illusion. Two experiments were done, in a dark room, in which distribution of depth cues is the same towards horizon as towards zenith. In the first experiment 14 participants had the task to equalize the perceived distances of three stimuli in three directions (horizontal, tilted 45 degrees and vertical). In the second experiment 16 participants had the task to estimate the perceived sizes of three stimuli in the same three directions. For distance estimates we found differences among three directions in a way, that as the head tilts upwards, the perceived space is being elongated, which is the opposite to flattened sky dome. For size estimates we found no difference among the three directions.

Attention Alters Perceived Attractiveness.

PubMed

Störmer, Viola S; Alvarez, George A

2016-04-01

Can attention alter the impression of a face? Previous studies showed that attention modulates the appearance of lower-level visual features. For instance, attention can make a simple stimulus appear to have higher contrast than it actually does. We tested whether attention can also alter the perception of a higher-order property-namely, facial attractiveness. We asked participants to judge the relative attractiveness of two faces after summoning their attention to one of the faces using a briefly presented visual cue. Across trials, participants judged the attended face to be more attractive than the same face when it was unattended. This effect was not due to decision or response biases, but rather was due to changes in perceptual processing of the faces. These results show that attention alters perceived facial attractiveness, and broadly demonstrate that attention can influence higher-level perception and may affect people's initial impressions of one another. © The Author(s) 2016.

How Weight Affects the Perceived Spacing between the Thumb and Fingers during Grasping

PubMed Central

Butler, Annie A.; Héroux, Martin E.; Gandevia, Simon C.

2015-01-01

We know much about mechanisms determining the perceived size and weight of lifted objects, but little about how these properties of size and weight affect the body representation (e.g. grasp aperture of the hand). Without vision, subjects (n = 16) estimated spacing between fingers and thumb (perceived grasp aperture) while lifting canisters of the same width (6.6cm) but varied weights (300, 600, 900, and 1200 g). Lifts were performed by movement of either the wrist, elbow or shoulder to examine whether lifting with different muscle groups affects the judgement of grasp aperture. Results for perceived grasp aperture were compared with changes in perceived weight of objects of different sizes (5.2, 6.6, and 10 cm) but the same weight (600 g). When canisters of the same width but different weights were lifted, perceived grasp aperture decreased 4.8% [2.2 ‒ 7.4] (mean [95% CI]; P < 0.001) from the lightest to the heaviest canister, no matter how they were lifted. For objects of the same weight but different widths, perceived weight decreased 42.3% [38.2 ‒ 46.4] from narrowest to widest (P < 0.001), as expected from the size-weight illusion. Thus, despite a highly distorted perception of the weight of objects based on their size, we conclude that proprioceptive afferents maintain a reasonably stable perception of the aperture of the grasping hand over a wide range of object weights. Given the small magnitude of this ‘weight-grasp aperture’ illusion, we propose the brain has access to a relatively stable ‘perceptual ruler’ to aid the manipulation of different objects. PMID:25996760

Fast and Forceful: Modulation of Response Activation Induced by Shifts of Perceived Depth in Virtual 3D Space

PubMed Central

Plewan, Thorsten; Rinkenauer, Gerhard

2016-01-01

Reaction time (RT) can strongly be influenced by a number of stimulus properties. For instance, there was converging evidence that perceived size rather than physical (i.e., retinal) size constitutes a major determinant of RT. However, this view has recently been challenged since within a virtual three-dimensional (3D) environment retinal size modulation failed to influence RT. In order to further investigate this issue in the present experiments response force (RF) was recorded as a supplemental measure of response activation in simple reaction tasks. In two separate experiments participants’ task was to react as fast as possible to the occurrence of a target located close to the observer or farther away while the offset between target locations was increased from Experiment 1 to Experiment 2. At the same time perceived target size (by varying the retinal size across depth planes) and target type (sphere vs. soccer ball) were modulated. Both experiments revealed faster and more forceful reactions when targets were presented closer to the observers. Perceived size and target type barely affected RT and RF in Experiment 1 but differentially affected both variables in Experiment 2. Thus, the present findings emphasize the usefulness of RF as a supplement to conventional RT measurement. On a behavioral level the results confirm that (at least) within virtual 3D space perceived object size neither strongly influences RT nor RF. Rather the relative position within egocentric (body-centered) space presumably indicates an object’s behavioral relevance and consequently constitutes an important modulator of visual processing. PMID:28018273

The Perceived Stress Levels of Primary and Secondary Principals.

ERIC Educational Resources Information Center

Savery, Lawson K.; Detiuk, Michael

1986-01-01

Research conducted in Western Australian government schools indicates perceived stress among principals, particularly role overload and role conflict. Primary principals experienced greater stress than secondary principals. Suggestions on how the education department can reduce employee stress include altering leadership styles and offering stress…

Linking models of human behaviour and climate alters projected climate change

DOE PAGES

Beckage, Brian; Gross, Louis J.; Lacasse, Katherine; ...

2018-01-01

Although not considered in climate models, perceived risk stemming from extreme climate events may induce behavioural changes that alter greenhouse gas emissions. Here, we link the C-ROADS climate model to a social model of behavioural change to examine how interactions between perceived risk and emissions behaviour influence projected climate change. Our coupled climate and social model resulted in a global temperature change ranging from 3.4–6.2 °C by 2100 compared with 4.9 °C for the C-ROADS model alone, and led to behavioural uncertainty that was of a similar magnitude to physical uncertainty (2.8 °C versus 3.5 °C). Model components with themore » largest influence on temperature were the functional form of response to extreme events, interaction of perceived behavioural control with perceived social norms, and behaviours leading to sustained emissions reductions. Lastly, our results suggest that policies emphasizing the appropriate attribution of extreme events to climate change and infrastructural mitigation may reduce climate change the most.« less

Linking models of human behaviour and climate alters projected climate change

NASA Astrophysics Data System (ADS)

Beckage, Brian; Gross, Louis J.; Lacasse, Katherine; Carr, Eric; Metcalf, Sara S.; Winter, Jonathan M.; Howe, Peter D.; Fefferman, Nina; Franck, Travis; Zia, Asim; Kinzig, Ann; Hoffman, Forrest M.

2018-01-01

Although not considered in climate models, perceived risk stemming from extreme climate events may induce behavioural changes that alter greenhouse gas emissions. Here, we link the C-ROADS climate model to a social model of behavioural change to examine how interactions between perceived risk and emissions behaviour influence projected climate change. Our coupled climate and social model resulted in a global temperature change ranging from 3.4-6.2 °C by 2100 compared with 4.9 °C for the C-ROADS model alone, and led to behavioural uncertainty that was of a similar magnitude to physical uncertainty (2.8 °C versus 3.5 °C). Model components with the largest influence on temperature were the functional form of response to extreme events, interaction of perceived behavioural control with perceived social norms, and behaviours leading to sustained emissions reductions. Our results suggest that policies emphasizing the appropriate attribution of extreme events to climate change and infrastructural mitigation may reduce climate change the most.

Linking models of human behaviour and climate alters projected climate change

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

Beckage, Brian; Gross, Louis J.; Lacasse, Katherine

Although not considered in climate models, perceived risk stemming from extreme climate events may induce behavioural changes that alter greenhouse gas emissions. Here, we link the C-ROADS climate model to a social model of behavioural change to examine how interactions between perceived risk and emissions behaviour influence projected climate change. Our coupled climate and social model resulted in a global temperature change ranging from 3.4–6.2 °C by 2100 compared with 4.9 °C for the C-ROADS model alone, and led to behavioural uncertainty that was of a similar magnitude to physical uncertainty (2.8 °C versus 3.5 °C). Model components with themore » largest influence on temperature were the functional form of response to extreme events, interaction of perceived behavioural control with perceived social norms, and behaviours leading to sustained emissions reductions. Lastly, our results suggest that policies emphasizing the appropriate attribution of extreme events to climate change and infrastructural mitigation may reduce climate change the most.« less

Evaluators' Perceptions of Teachers' Use of Behavior Alteration Techniques.

ERIC Educational Resources Information Center

Allen, Terre; Edwards, Renee

1988-01-01

Examines which message-based behavior alteration techniques (BATs) teacher evaluators perceive as commonly used by good, average, and poor teachers. Reports that principals equate reward-type messages with effective teaching and punishment-type messages with ineffective teaching. (MM)

A preconscious neural mechanism of hypnotically altered colors: a double case study.

PubMed

Koivisto, Mika; Kirjanen, Svetlana; Revonsuo, Antti; Kallio, Sakari

2013-01-01

Hypnotic suggestions may change the perceived color of objects. Given that chromatic stimulus information is processed rapidly and automatically by the visual system, how can hypnotic suggestions affect perceived colors in a seemingly immediate fashion? We studied the mechanisms of such color alterations by measuring electroencephalography in two highly suggestible participants as they perceived briefly presented visual shapes under posthypnotic color alternation suggestions such as "all the squares are blue". One participant consistently reported seeing the suggested colors. Her reports correlated with enhanced evoked upper beta-band activity (22 Hz) 70-120 ms after stimulus in response to the shapes mentioned in the suggestion. This effect was not observed in a control condition where the participants merely tried to simulate the effects of the suggestion on behavior. The second participant neither reported color alterations nor showed the evoked beta activity, although her subjective experience and event-related potentials were changed by the suggestions. The results indicate a preconscious mechanism that first compares early visual input with a memory representation of the suggestion and consequently triggers the color alteration process in response to the objects specified by the suggestion. Conscious color experience is not purely the result of bottom-up processing but it can be modulated, at least in some individuals, by top-down factors such as hypnotic suggestions.

Why Barbie Feels Heavier than Ken: The Influence of Size-Based Expectancies and Social Cues on the Illusory Perception of Weight

ERIC Educational Resources Information Center

Dijker, Anton J. M.

2008-01-01

In order to examine the relative influence of size-based expectancies and social cues on the perceived weight of objects, two studies were performed, using equally weighing dolls differing in sex-related and age-related vulnerability or physical strength cues. To increase variation in perceived size, stimulus objects were viewed through optical…

When perception reflects reality: Non-native grass invasion alters small mammal risk landscapes and survival

USGS Publications Warehouse

Ceradnini, Joseph P.; Chalfoun, Anna D.

2017-01-01

Modification of habitat structure due to invasive plants can alter the risk landscape for wildlife by, for example, changing the quality or availability of refuge habitat. Whether perceived risk corresponds with actual fitness outcomes, however, remains an important open question. We simultaneously measured how habitat changes due to a common invasive grass (cheatgrass, Bromus tectorum) affected the perceived risk, habitat selection, and apparent survival of a small mammal, enabling us to assess how well perceived risk influenced important behaviors and reflected actual risk. We measured perceived risk by nocturnal rodents using a giving-up density foraging experiment with paired shrub (safe) and open (risky) foraging trays in cheatgrass and native habitats. We also evaluated microhabitat selection across a cheatgrass gradient as an additional assay of perceived risk and behavioral responses for deer mice (Peromyscus maniculatus) at two spatial scales of habitat availability. Finally, we used mark-recapture analysis to quantify deer mouse apparent survival across a cheatgrass gradient while accounting for detection probability and other habitat features. In the foraging experiment, shrubs were more important as protective cover in cheatgrass-dominated habitats, suggesting that cheatgrass increased perceived predation risk. Additionally, deer mice avoided cheatgrass and selected shrubs, and marginally avoided native grass, at two spatial scales. Deer mouse apparent survival varied with a cheatgrass–shrub interaction, corresponding with our foraging experiment results, and providing a rare example of a native plant mediating the effects of an invasive plant on wildlife. By synthesizing the results of three individual lines of evidence (foraging behavior, habitat selection, and apparent survival), we provide a rare example of linkage between behavioral responses of animals indicative of perceived predation risk and actual fitness outcomes. Moreover, our results suggest that exotic grass invasions can influence wildlife populations by altering risk landscapes and survival.

Perceived Chronic Stress Exposure Modulates Reward-Related Medial Prefrontal Cortex Responses to Acute Stress in Depression

PubMed Central

Kumar, Poornima; Slavich, George M.; Berghorst, Lisa H.; Treadway, Michael T.; Brooks, Nancy H.; Dutra, Sunny J.; Greve, Douglas N.; O'Donovan, Aoife; Bleil, Maria E.; Maninger, Nicole; Pizzagalli, Diego A.

2015-01-01

Introduction Major depressive disorder (MDD) is often precipitated by life stress and growing evidence suggests that stress-induced alterations in reward processing may contribute to such risk. However, no human imaging studies have examined how recent life stress exposure modulates the neural systems that underlie reward processing in depressed and healthy individuals. Methods In this proof-of-concept study, 12 MDD and 10 psychiatrically healthy individuals were interviewed using the Life Events and Difficulties Schedule (LEDS) to assess their perceived levels of recent acute and chronic life stress exposure. Additionally, each participant performed a monetary incentive delay task under baseline (no-stress) and stress (social-evaluative) conditions during functional MRI. Results Across groups, medial prefrontal cortex (mPFC) activation to reward feedback was greater during acute stress versus no-stress conditions in individuals with greater perceived stressor severity. Under acute stress, depressed individuals showed a positive correlation between perceived stressor severity levels and reward-related mPFC activation (r = 0.79, p = 0.004), whereas no effect was found in healthy controls. Moreover, for depressed (but not healthy) individuals, the correlations between the stress (r = 0.79) and no-stress (r = −0.48) conditions were significantly different. Finally, relative to controls, depressed participants showed significantly reduced mPFC grey matter, but functional findings remained when accounting for structural differences. Limitation Small sample size, which warrants replication. Conclusion Depressed individuals experiencing greater recent life stress recruited the mPFC more under stress when processing rewards. Our results represent an initial step toward elucidating mechanisms underlying stress sensitization and recurrence in depression. PMID:25898329

Perceived size of friends and weight evaluation among low-income adolescents

PubMed Central

Milan, Stephanie

2018-01-01

Drawing from social comparison theory, we examine how perceptions of friends’ body sizes may influence adolescents’ subjective evaluations of their own body (e.g., how accurate they are in judging their weight, how much body dissatisfaction they feel), particularly for adolescent females. Participants were low-income, minority adolescents (Study 1: N = 194 females, Mean age = 15.4; Study 2: N = 409 males and females; Mean age = 14.9). Adolescents used figure rating scales to indicate their perceived size and that of four of their closest friends and completed several measures of subjective weight evaluation (e.g., weight classification, body dissatisfaction, internalized weight bias). In both studies, how adolescents perceived their body size and the body sizes of their thinnest and heaviest friends were positively correlated. In Study 1, overweight females based on measured BMI were less likely to accurately judge themselves as overweight if they had a close friend they perceived as heavy. In addition, females who viewed themselves as having a larger figure reported more internalized weight bias when they had friends they viewed as relatively thin. Findings from Study 2 suggest that how friends’ bodies are perceived is predictive of subjective weight evaluation measures only for adolescent females. Programs that address negative aspects of social comparison may be important in preventing both obesity and eating disorder symptoms in adolescent females. PMID:26403505

A flight by periscope and where it landed.

PubMed

Roscoe, Stanley N; Acosta, Hector M

2008-06-01

This study defines display design factors linking visual accommodation and the perceived size of distant objects. In 1947, in anticipation of augmented contact and sensor-relayed contact displays, a periscope was installed in an airplane to serve as a sensor-based contact display simulator. To achieve normal landing performance, however, the unity image had to be magnified. This successful intervention, first published in 1966 in Human Factors, implicated oculomotor mechanisms and higher perceptual functions and became the observational basis for a series of investigative hypotheses. Observers registered the perceived size of the collimated image of a "moon" by adjusting a disk of light while alternatively providing optometric measurements of accommodative distance. Various investigators found high correlations between focal distances and perceived moon sizes. The simulated moon provided a superior vehicle for revealing the relationship between focal distance and perceived size and the factors affecting both. The operational display design implications and the possibility of a partial explanation for the moon illusion provided the motivation for an important doctoral research project involving eight factors that affect both focal distance and perceived size. The investigation reaffirmed that virtual images, as found in head-up and head-mounted displays (HUDs and HMDs, respectively), do not consistently draw focus to optical infinity and that a variety of factors necessarily manipulated by display designers and present in many operational systems can affect visual performance partially through the mediation of accommodation.

Beliefs about penis size: validation of a scale for men ashamed about their penis size.

PubMed

Veale, David; Eshkevari, Ertimiss; Read, Julie; Miles, Sarah; Troglia, Andrea; Phillips, Rachael; Echeverria, Lina Maria Carmona; Fiorito, Chiara; Wylie, Kevan; Muir, Gordon

2014-01-01

No measures are available for understanding beliefs in men who experience shame about the perceived size of their penis. Such a measure might be helpful for treatment planning, and measuring outcome after any psychological or physical intervention. Our aim was to validate a newly developed measure called the Beliefs about Penis Size Scale (BAPS). One hundred seventy-three male participants completed a new questionnaire consisting of 18 items to be validated and developed into the BAPS, as well as various other standardized measures. A urologist also measured actual penis size. The BAPS was validated against six psychosexual self-report questionnaires as well as penile size measurements. Exploratory factor analysis reduced the number of items in the BAPS from 18 to 10, which was best explained by one factor. The 10-item BAPS had good internal consistency and correlated significantly with measures of depression, anxiety, body image quality of life, social anxiety, erectile function, overall satisfaction, and the importance attached to penis size. The BAPS was not found to correlate with actual penis size. It was able to discriminate between those who had concerns or were dissatisfied about their penis size and those who were not. This is the first study to develop a scale for measurement of beliefs about penis size. It may be used as part of an assessment for men who experience shame about the perceived size of their penis and as an outcome measure after treatment. The BAPS measures various manifestations of masculinity and shame about their perceived penis size including internal self-evaluative beliefs; negative evaluation by others; anticipated consequences of a perceived small penis, and extreme self-consciousness. © 2013 International Society for Sexual Medicine.

Perceived Spaciousness and Preference in Sequential Experience.

PubMed

Bokharaei, Saleheh; Nasar, Jack L

2016-11-01

We assessed the perceived spaciousness and preference for a destination space in relation to six attributes (size, lighting, window size, texture, wall mural, and amount of furniture) of it and of the space experienced before it. Studies have examined effects of these attributes but not for dynamic experience or preference. We created 24 virtual reality walks between each possible pair of two levels of each attribute. For each destination space, 31 students (13 men, 18 women) rated spaciousness and 30 students (16 men, 14 women) rated preference. We conducted separate 2 × 2 repeated-measure ANOVAs across each condition for perceived spaciousness and preference. Participants judged the space that was larger, was more brightly lit, with a larger window, or with less furniture as the more spacious. These attributes also increased preference. Consonant with adaptation-level theory, participants judged offices as higher in spaciousness and preference if preceded by a space that was smaller, was more dimly lit, or had smaller windows. The findings suggest that perceived spaciousness varies with size, lightness, window size, and amount of furniture but that perception also depends on the size, lightness, and size of the space experienced before. Designers could use the findings to manipulate features to make a space appear larger or more desirable. © 2016, Human Factors and Ergonomics Society.

Comparative study of stress and quality of life in outpatients consulting for different dermatoses in 5 academic departments of dermatology.

PubMed

Misery, Laurent; Thomas, Luc; Jullien, Denis; Cambazard, Frédéric; Humbert, Philippe; Dubertret, Louis; Dehen, Laure; Macy, Guy; Boussetta, Sami; Taieb, Charles

2008-01-01

In this study, perceived stress and quality of life were measured with PCV-Metra and SF-12 scales in outpatients consulting for different dermatoses in 5 academic dermatology departments for 5 consecutive days. 658 patients were enrolled in the study. Perceived stress was higher in women and the mental component of their quality of life was more altered. Perceived stress was higher in Paris than in other areas and was respectively 11.4, 10.4, 9.2 and 8.9 for psoriasis, acne, atopic dermatitis and pigmented tumours. Perceived stress was correlated to mental quality of life. Stress was more elevated in people with inflammatory dermatoses than in those with tumours. To our knowledge, this is the first comparative study of both stress and quality of life levels in different dermatoses. Stress levels were lower in people with pigmented tumours, suggesting that they can be used as controls in comparative studies because they can be considered as healthy subjects. On the contrary, patients with psoriasis had a very high level of perceived stress and a deeply altered quality of life.

Social Capital, Place Meanings, and Perceived Resilience to Climate Change

ERIC Educational Resources Information Center

Smith, Jordan W.; Anderson, Dorothy H.; Moore, Roger L.

2012-01-01

This research analyzes individuals' perceived resilience to changing climatic conditions. Specifically, we suggest individual resilience is composed of an awareness of localized risks created because of climate change, a willingness to learn about, and plan for, the potential impacts of altered environmental conditions, and general appraisals of…

Combining the role of convenience and consideration set size in explaining fish consumption in Norway.

PubMed

Rortveit, Asbjorn Warvik; Olsen, Svein Ottar

2009-04-01

The purpose of this study is to explore how convenience orientation, perceived product inconvenience and consideration set size are related to attitudes towards fish and fish consumption. The authors present a structural equation model (SEM) based on the integration of two previous studies. The results of a SEM analysis using Lisrel 8.72 on data from a Norwegian consumer survey (n=1630) suggest that convenience orientation and perceived product inconvenience have a negative effect on both consideration set size and consumption frequency. Attitude towards fish has the greatest impact on consumption frequency. The results also indicate that perceived product inconvenience is a key variable since it has a significant impact on attitude, and on consideration set size and consumption frequency. Further, the analyses confirm earlier findings suggesting that the effect of convenience orientation on consumption is partially mediated through perceived product inconvenience. The study also confirms earlier findings suggesting that the consideration set size affects consumption frequency. Practical implications drawn from this research are that the seafood industry would benefit from developing and positioning products that change beliefs about fish as an inconvenient product. Future research for other food categories should be done to enhance the external validity.

Integrated Cuing Requirements (ICR) Study: Demonstration Data Base and Users Guide.

DTIC Science & Technology

1983-07-01

viewed with a servo-mounted televison camera and used to provide a visual scene for an observer in an ATD. Modulation: Mathematically, the absolute...i(b). CROSS REFERENCE The impact of stationary scene RESULTS. . details was also tested in this See (c) study. See Figure 33.5-1. Ial TEST APPARATUS...size. (See the discussion of * the impact of perceived distance on perceived size in Section 31._.) Figure 33.4-1 Perceived Distance and Velocity of Self

Out of control mortality matters: the effect of perceived uncontrollable mortality risk on a health-related decision.

PubMed

Pepper, Gillian V; Nettle, Daniel

2014-01-01

Prior evidence from the public health literature suggests that both control beliefs and perceived threats to life are important for health behaviour. Our previously presented theoretical model generated the more specific hypothesis that uncontrollable, but not controllable, personal mortality risk should alter the payoff from investment in health protection behaviours. We carried out three experiments to test whether altering the perceived controllability of mortality risk would affect a health-related decision. Experiment 1 demonstrated that a mortality prime could be used to alter a health-related decision: the choice between a healthier food reward (fruit) and an unhealthy alternative (chocolate). Experiment 2 demonstrated that it is the controllability of the mortality risk being primed that generates the effect, rather than mortality risk per se. Experiment 3 showed that the effect could be seen in a surreptitious experiment that was not explicitly health related. Our results suggest that perceptions about the controllability of mortality risk may be an important factor in people's health-related decisions. Thus, techniques for adjusting perceptions about mortality risk could be important tools for use in health interventions. More importantly, tackling those sources of mortality that people perceive to be uncontrollable could have a dual purpose: making neighbourhoods and workplaces safer would have the primary benefit of reducing uncontrollable mortality risk, which could lead to a secondary benefit from improved health behaviours.

Bodily Sensory Inputs and Anomalous Bodily Experiences in Complex Regional Pain Syndrome: Evaluation of the Potential Effects of Sound Feedback

PubMed Central

Tajadura-Jiménez, Ana; Cohen, Helen; Bianchi-Berthouze, Nadia

2017-01-01

Neuroscientific studies have shown that human's mental body representations are not fixed but are constantly updated through sensory feedback, including sound feedback. This suggests potential new therapeutic sensory approaches for patients experiencing body-perception disturbances (BPD). BPD can occur in association with chronic pain, for example in Complex Regional Pain Syndrome (CRPS). BPD often impacts on emotional, social, and motor functioning. Here we present the results from a proof-of-principle pilot study investigating the potential value of using sound feedback for altering BPD and its related emotional state and motor behavior in those with CRPS. We build on previous findings that real-time alteration of the sounds produced by walking can alter healthy people's perception of their own body size, while also resulting in more active gait patterns and a more positive emotional state. In the present study we quantified the emotional state, BPD, pain levels and gait of twelve people with CRPS Type 1, who were exposed to real-time alteration of their walking sounds. Results confirm previous reports of the complexity of the BPD linked to CRPS, as participants could be classified into four BPD subgroups according to how they mentally visualize their body. Further, results suggest that sound feedback may affect the perceived size of the CRPS affected limb and the pain experienced, but that the effects may differ according to the type of BPD. Sound feedback affected CRPS descriptors and other bodily feelings and emotions including feelings of emotional dominance, limb detachment, position awareness, attention and negative feelings toward the limb. Gait also varied with sound feedback, affecting the foot contact time with the ground in a way consistent with experienced changes in body weight. Although, findings from this small pilot study should be interpreted with caution, they suggest potential applications for regenerating BDP and its related bodily feelings in a clinical setting for patients with chronic pain and BPD. PMID:28798671

Impaired flexible decision-making in Major Depressive Disorder.

PubMed

Cella, Matteo; Dymond, Simon; Cooper, Andy

2010-07-01

Depression is associated with dysfunctional affective states, neuropsychological impairment and altered sensitivity to reward and punishment. These impairments can influence complex decision-making in changing environments. The contingency shifting variant Iowa Gambling Task (IGT) was used to assess flexible decision-making performance in a group of medicated unipolar Major Depressive Disorder (MDD) patients (n=19) and a group of healthy control volunteers (n=20). The task comprised the standard IGT followed by a contingency-shift phase where decks progressively changed reward and punishment schedule. Patients with MDD showed impaired performance compared to controls during both the standard and the contingency-shift phases of the IGT. Analysis of the contingency-shift phase demonstrated that individuals with depression had difficulties perceiving when a previously bad contingency became good. The present findings have several limitations including small sample size, the possible confounding role of medication and absence of other neuropsychological tests (i.e., executive function). Depressed patients show impaired decision-making behaviour in static and dynamic environments. Altered sensitivity to reward and punishment is proposed as the mechanism responsible for the lack of advantageous choices and poor adjustment to a changing environment.

Endothelial cells respond to the direction of mechanical stimuli through SMAD signaling to regulate coronary artery size.

PubMed

Poduri, Aruna; Chang, Andrew H; Raftrey, Brian; Rhee, Siyeon; Van, Mike; Red-Horse, Kristy

2017-09-15

How mechanotransduction intersects with chemical and transcriptional factors to shape organogenesis is an important question in developmental biology. This is particularly relevant to the cardiovascular system, which uses mechanical signals from flowing blood to stimulate cytoskeletal and transcriptional responses that form a highly efficient vascular network. Using this system, artery size and structure are tightly regulated, but the underlying mechanisms are poorly understood. Here, we demonstrate that deletion of Smad4 increased the diameter of coronary arteries during mouse embryonic development, a phenotype that followed the initiation of blood flow. At the same time, the BMP signal transducers SMAD1/5/8 were activated in developing coronary arteries. In a culture model of blood flow-induced shear stress, human coronary artery endothelial cells failed to align when either BMPs were inhibited or SMAD4 was depleted. In contrast to control cells, SMAD4- deficient cells did not migrate against the direction of shear stress and increased proliferation rates specifically under flow. Similar alterations were seen in coronary arteries in vivo Thus, endothelial cells perceive the direction of blood flow and respond through SMAD signaling to regulate artery size. © 2017. Published by The Company of Biologists Ltd.

Pressure-controlled treadmill training in chronic stroke: a case study with AlterG.

PubMed

Lathan, Cherise; Myler, Andrew; Bagwell, Jennifer; Powers, Christopher M; Fisher, Beth E

2015-04-01

Body-weight-supported treadmill training has been shown to be an effective intervention to improve walking characteristics for individuals who have experienced a stroke. A pressure-controlled treadmill utilizes a sealed chamber in which air pressure can be altered in a controlled manner to counteract the effects of gravity. The focus of this case study was to assess the immediate and short-term impact of a pressure-controlled treadmill to improve gait parameters, reduce fall risk, improve participation, and reduce the self-perceived negative impact of stroke in an individual with chronic stroke. The subject was an 81-year-old man (14.5 months poststroke). He had slow walking speed, poor endurance, and multiple gait deviations. The subject trained 4 times per week for 4 weeks (40 minutes per session) on a pressure-controlled treadmill (AlterG M320) to counter the influence of gravity on the lower extremities. Following training, self-selected gait speed increased from 0.50 m/s to 0.96 m/s, as measured by the 10-meter walk test. Stride length increased from 0.58 m to 0.95 m after training and to 1.00 m at 1-month follow-up. Peak hip flexion increased from 3.7° to 24.6° after training and to 19.4° at 1-month follow-up. Peak knee flexion increased from 19.4° to 34.3° after training and to 42.7° at 1-month follow-up. Measures of endurance, fall risk, and percentage of perceived recovery also were found to improve posttraining. Training with a pressure-controlled treadmill may be a viable alternative to traditional body-weight-supported treadmill training for persons poststroke. Additional studies with larger sample sizes are needed to elucidate the role of pressure-controlled treadmill training in this population. Video abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A97).

Psychophysical Test for the Independence of Perception and Action

ERIC Educational Resources Information Center

Amazeen, Eric L.; DaSilva, Flavio

2005-01-01

Research has suggested that perception and action are independent (see M. A. Goodale & A. Haffenden, 1998). The authors used the Ebbinghaus illusion to test this hypothesis in 2 experiments. Verbal reports of perceived size were compared with maximum grip aperture during grasping (Experiment 1) and manual reports of perceived size (Experiment 2).…

Perception of Foreign Accent Syndrome Speech and Its Relation to Segmental Characteristics

ERIC Educational Resources Information Center

Dankovicova, Jana; Hunt, Claire

2011-01-01

Foreign accent syndrome (FAS) is an acquired neurogenic disorder characterized by altered speech that sounds foreign-accented. This study presents a British subject perceived to speak with an Italian (or Greek) accent after a brainstem (pontine) stroke. Native English listeners rated the strength of foreign accent and impairment they perceived in…

Perceived Intensity of Emotional Point-Light Displays Is Reduced in Subjects with ASD

ERIC Educational Resources Information Center

Krüger, Britta; Kaletsch, Morten; Pilgramm, Sebastian; Schwippert, Sven-Sören; Hennig, Jürgen; Stark, Rudolf; Lis, Stefanie; Gallhofer, Bernd; Sammer, Gebhard; Zentgraf, Karen; Munzert, Jörn

2018-01-01

One major characteristic of autism spectrum disorder (ASD) is problems with social interaction and communication. The present study explored ASD-related alterations in perceiving emotions expressed via body movements. 16 participants with ASD and 16 healthy controls observed video scenes of human interactions conveyed by point-light displays. They…

From the Cover: Explaining the moon illusion

NASA Astrophysics Data System (ADS)

Kaufman, Lloyd; Kaufman, James H.

2000-01-01

An old explanation of the moon illusion holds that various cues place the horizon moon at an effectively greater distance than the elevated moon. Although both moons have the same angular size, the horizon moon must be perceived as larger. More recent explanations hold that differences in accommodation or other factors cause the elevated moon to appear smaller. As a result of this illusory difference in size, the elevated moon appears to be more distant than the horizon moon. These two explanations, both based on the geometry of stereopsis, lead to two diametrically opposed hypotheses. That is, a depth interval at a long distance is associated with a smaller binocular disparity, whereas an equal depth interval at a smaller distance is associated with a larger disparity. We conducted experiments involving artificial moons and confirmed the hypothesis that the horizon moon is at a greater perceptual distance. Moreover, when a moon of constant angular size was moved closer it was also perceived as growing smaller, which is consistent with the older explanation. Although Emmert's law does not predict the size-distance relationship over long distances, we conclude that the horizon moon is perceived as larger because the perceptual system treats it as though it is much farther away. Finally, we observe that recent explanations substitute perceived size for angular size as a cue to distance. Thus, they imply that perceptions cause perceptions.

Explaining the moon illusion.

PubMed

Kaufman, L; Kaufman, J H

2000-01-04

An old explanation of the moon illusion holds that various cues place the horizon moon at an effectively greater distance than the elevated moon. Although both moons have the same angular size, the horizon moon must be perceived as larger. More recent explanations hold that differences in accommodation or other factors cause the elevated moon to appear smaller. As a result of this illusory difference in size, the elevated moon appears to be more distant than the horizon moon. These two explanations, both based on the geometry of stereopsis, lead to two diametrically opposed hypotheses. That is, a depth interval at a long distance is associated with a smaller binocular disparity, whereas an equal depth interval at a smaller distance is associated with a larger disparity. We conducted experiments involving artificial moons and confirmed the hypothesis that the horizon moon is at a greater perceptual distance. Moreover, when a moon of constant angular size was moved closer it was also perceived as growing smaller, which is consistent with the older explanation. Although Emmert's law does not predict the size-distance relationship over long distances, we conclude that the horizon moon is perceived as larger because the perceptual system treats it as though it is much farther away. Finally, we observe that recent explanations substitute perceived size for angular size as a cue to distance. Thus, they imply that perceptions cause perceptions.

Relationship Between Auditory Context and Visual Distance Perception: Effect of Musical Expertise in the Ability to Translate Reverberation Cues Into Room-Size Perception.

PubMed

Etchemendy, Pablo E; Spiousas, Ignacio; Vergara, Ramiro

2018-01-01

In a recently published work by our group [ Scientific Reports, 7, 7189 (2017)], we performed experiments of visual distance perception in two dark rooms with extremely different reverberation times: one anechoic ( T ∼ 0.12 s) and the other reverberant ( T ∼ 4 s). The perceived distance of the targets was systematically greater in the reverberant room when contrasted to the anechoic chamber. Participants also provided auditorily perceived room-size ratings which were greater for the reverberant room. Our hypothesis was that distance estimates are affected by room size, resulting in farther responses for the room perceived larger. Of much importance to the task was the subjects' ability to infer room size from reverberation. In this article, we report a postanalysis showing that participants having musical expertise were better able to extract and translate reverberation cues into room-size information than nonmusicians. However, the degree to which musical expertise affects visual distance estimates remains unclear.

Development and Validation of an Instrument for Early Assessment of Management Potential in a Mid-Size Chemical Company

ERIC Educational Resources Information Center

Zehner, Robert L.; Holton, Elwood F., III

2004-01-01

This study reports on development and concurrent validation of a competency instrument to identify potential leaders in a mid-size chemical company. Four competencies were identified: courageous problem solving, perceived energy, networking, and perceived motivation. Four different comparison groups were examined in logistic regression analyses.…

Body size dissatisfaction among young adults from the 1982 Pelotas birth cohort

PubMed Central

Mintem, G C; Horta, B L; Domingues, M R; Gigante, D P

2015-01-01

Background/Objectives: To identify the prevalence and factors associated with body dissatisfaction. Subjects/Methods: Birth cohort study investigating 4100 subjects (2187 men and 1913 women) aged between 22 and 23 years who answered questionnaires, including the body satisfaction Stunkard Scale were included in the study; they were weighed and measured. Multinomial logistic regression was used in the crude and adjusted analyses. Results: The prevalence of body dissatisfaction was 64% (95% CI, 62.7–65.6); 42% (95% CI, 40.6–43.6) of the subjects reported feeling larger than the desired body size, and 22% (95% CI, 20.7–23.3) reported feeling smaller than desired. Underweight subjects, subjects with less schooling, poor and sedentary male subjects with low psychological well-being and female subjects who were already mothers were more likely to express body dissatisfaction, perceiving their body as smaller than the desirable body size. The prevalence of body dissatisfaction was also high among overweight subjects, subjects with a high socioeconomic status and married female subjects, who perceived their body size as too large. Minor psychiatric disorders were associated with body dissatisfaction in all subjects, regardless of perceiving themselves as larger or smaller than the desired body size. Most women perceived themselves as larger, but similar proportions of men perceived themselves as too small or too large. Conclusions: Body dissatisfaction was observed among men and women with normal weight, but it was more evident in the obese individuals. Regardless of the nutritional status, both men and women should be appropriately counseled because body size perception can lead to unhealthy behaviors in relation to diet and physical activity. PMID:25074390

Putting to a bigger hole: Golf performance relates to perceived size

PubMed Central

Witt, Jessica K.; Linkenauger, Sally A.; Bakdash, Jonathan Z.; Proffitt, Dennis R.

2011-01-01

When engaged in a skilled behaviour such as occurs in sports, people's perceptions relate optical information to their performance. In current research we demonstrate the effects of performance on size perception in golfers. We found golfers who played better judged the hole to be bigger than golfers who did not play as well (Study 1). In follow-up laboratory experiments, participants putted on a golf mat from a location near or far from the hole then judged the size of the hole. Participants who putted from the near location perceived the hole to be bigger than participants who putted from the far location. Our results demonstrate that perception is influenced by the perceiver's current ability to act effectively in the environment. PMID:18567258

Perceived life stress exposure modulates reward-related medial prefrontal cortex responses to acute stress in depression.

PubMed

Kumar, Poornima; Slavich, George M; Berghorst, Lisa H; Treadway, Michael T; Brooks, Nancy H; Dutra, Sunny J; Greve, Douglas N; O'Donovan, Aoife; Bleil, Maria E; Maninger, Nicole; Pizzagalli, Diego A

2015-07-15

Major depressive disorder (MDD) is often precipitated by life stress and growing evidence suggests that stress-induced alterations in reward processing may contribute to such risk. However, no human imaging studies have examined how recent life stress exposure modulates the neural systems that underlie reward processing in depressed and healthy individuals. In this proof-of-concept study, 12 MDD and 10 psychiatrically healthy individuals were interviewed using the Life Events and Difficulties Schedule (LEDS) to assess their perceived levels of recent acute and chronic life stress exposure. Additionally, each participant performed a monetary incentive delay task under baseline (no-stress) and stress (social-evaluative) conditions during functional MRI. Across groups, medial prefrontal cortex (mPFC) activation to reward feedback was greater during acute stress versus no-stress conditions in individuals with greater perceived stressor severity. Under acute stress, depressed individuals showed a positive correlation between perceived stressor severity levels and reward-related mPFC activation (r=0.79, p=0.004), whereas no effect was found in healthy controls. Moreover, for depressed (but not healthy) individuals, the correlations between the stress (r=0.79) and no-stress (r=-0.48) conditions were significantly different. Finally, relative to controls, depressed participants showed significantly reduced mPFC gray matter, but functional findings remained robust while accounting for structural differences. Small sample size, which warrants replication. Depressed individuals experiencing greater recent life stress recruited the mPFC more under stress when processing rewards. Our results represent an initial step toward elucidating mechanisms underlying stress sensitization and recurrence in depression. Copyright © 2015 Elsevier B.V. All rights reserved.

Assessing the influence of skin color and tooth shade value on perceived smile attractiveness.

PubMed

Sabherwal, Ruchika S; Gonzalez, Juan; Naini, Farhad B

2009-06-01

The authors conducted a study to determine whether variations in skin color would influence perceptions of smile attractiveness for a given tooth shade value. Using a photograph of a woman smiling, the authors altered skin color to consist of four tones (fair, fair/medium, medium/dark and dark) and altered tooth shade value (brightness) to range from 00 (brightest) to 05 (darkest). Two groups of judges (70 dentists, 70 laypeople) completed a questionnaire and rated the images for smile attractiveness. For most tooth shade values (00, 01, 03, 04, 05), multiple mixed linear regression showed that variation in skin color influenced respondents' perceptions of smile attractiveness (P < .001). For images corresponding to tooth shade values 01, 02, 03, 04 and 05, men provided lower ratings than did women (P < .05). Attractiveness ratings increased with the age of participants (P < .05). Dentists rated images higher than did laypeople (P < .05). Variation in skin color for most tooth shade values influenced dentists' and laypeople's perceived smile attractiveness. Dentists and laypeople did not perceive the brightest tooth shade to be the most attractive, and they did not perceive all skin colors to be equally attractive with bright white teeth. Respondents perceived dark skin with bright white teeth and fair skin with dark teeth as relatively unattractive.

Power in the Classroom VII: Linking Behavior Alteration Techniques to Cognitive Learning.

ERIC Educational Resources Information Center

Richmond, Virginia P.; And Others

1987-01-01

Argues that Behavior Alteration Techniques (BATs) improve students' on-task compliance which, in turn, is consistently associated with achievement. Indicates a substantial relationship between BAT use and cognitive learning on both absolute and relative measures of achievement. Shows that the teachers perceived by students as "good"…

Age-Related Changes to Spectral Voice Characteristics Affect Judgments of Prosodic, Segmental, and Talker Attributes for Child and Adult Speech

ERIC Educational Resources Information Center

Dilley, Laura C.; Wieland, Elizabeth A.; Gamache, Jessica L.; McAuley, J. Devin; Redford, Melissa A.

2013-01-01

Purpose: As children mature, changes in voice spectral characteristics co-vary with changes in speech, language, and behavior. In this study, spectral characteristics were manipulated to alter the perceived ages of talkers' voices while leaving critical acoustic-prosodic correlates intact, to determine whether perceived age differences were…

Size matters: Perceived depth magnitude varies with stimulus height.

PubMed

Tsirlin, Inna; Wilcox, Laurie M; Allison, Robert S

2016-06-01

Both the upper and lower disparity limits for stereopsis vary with the size of the targets. Recently, Tsirlin, Wilcox, and Allison (2012) suggested that perceived depth magnitude from stereopsis might also depend on the vertical extent of a stimulus. To test this hypothesis we compared apparent depth in small discs to depth in long bars with equivalent width and disparity. We used three estimation techniques: a virtual ruler, a touch-sensor (for haptic estimates) and a disparity probe. We found that depth estimates were significantly larger for the bar stimuli than for the disc stimuli for all methods of estimation and different configurations. In a second experiment, we measured perceived depth as a function of the height of the bar and the radius of the disc. Perceived depth increased with increasing bar height and disc radius suggesting that disparity is integrated along the vertical edges. We discuss size-disparity correlation and inter-neural excitatory connections as potential mechanisms that could account for these results. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Visual System's Intrinsic Bias and Knowledge of Size Mediate Perceived Size and Location in the Dark

ERIC Educational Resources Information Center

Zhou, Liu; He, Zijiang J.; Ooi, Teng Leng

2013-01-01

Dimly lit targets in the dark are perceived as located about an implicit slanted surface that delineates the visual system's intrinsic bias (Ooi, Wu, & He, 2001). If the intrinsic bias reflects the internal model of visual space--as proposed here--its influence should extend beyond target localization. Our first 2 experiments demonstrated that…

Auditory environmental context affects visual distance perception.

PubMed

Etchemendy, Pablo E; Abregú, Ezequiel; Calcagno, Esteban R; Eguia, Manuel C; Vechiatti, Nilda; Iasi, Federico; Vergara, Ramiro O

2017-08-03

In this article, we show that visual distance perception (VDP) is influenced by the auditory environmental context through reverberation-related cues. We performed two VDP experiments in two dark rooms with extremely different reverberation times: an anechoic chamber and a reverberant room. Subjects assigned to the reverberant room perceived the targets farther than subjects assigned to the anechoic chamber. Also, we found a positive correlation between the maximum perceived distance and the auditorily perceived room size. We next performed a second experiment in which the same subjects of Experiment 1 were interchanged between rooms. We found that subjects preserved the responses from the previous experiment provided they were compatible with the present perception of the environment; if not, perceived distance was biased towards the auditorily perceived boundaries of the room. Results of both experiments show that the auditory environment can influence VDP, presumably through reverberation cues related to the perception of room size.

Recognition Alters the Spatial Pattern of fMRI Activation in Early Retinotopic Cortex

PubMed Central

Vul, E.; Kanwisher, N.

2010-01-01

Early retinotopic cortex has traditionally been viewed as containing a veridical representation of the low-level properties of the image, not imbued by high-level interpretation and meaning. Yet several recent results indicate that neural representations in early retinotopic cortex reflect not just the sensory properties of the image, but also the perceived size and brightness of image regions. Here we used functional magnetic resonance imaging pattern analyses to ask whether the representation of an object in early retinotopic cortex changes when the object is recognized compared with when the same stimulus is presented but not recognized. Our data confirmed this hypothesis: the pattern of response in early retinotopic visual cortex to a two-tone “Mooney” image of an object was more similar to the response to the full grayscale photo version of the same image when observers knew what the two-tone image represented than when they did not. Further, in a second experiment, high-level interpretations actually overrode bottom-up stimulus information, such that the pattern of response in early retinotopic cortex to an identified two-tone image was more similar to the response to the photographic version of that stimulus than it was to the response to the identical two-tone image when it was not identified. Our findings are consistent with prior results indicating that perceived size and brightness affect representations in early retinotopic visual cortex and, further, show that even higher-level information—knowledge of object identity—also affects the representation of an object in early retinotopic cortex. PMID:20071627

An Examination of Self-Perceived Transformational Leadership Behaviors of Texas Superintendents

ERIC Educational Resources Information Center

Fenn, Walter Lloyd; Mixon, Jason

2011-01-01

This study examined self-perceived transformational leadership behaviors among Texas superintendents. The purpose of this study was to examine if relationships existed between superintendents' self-perceived transformational leadership style, district size, teaching, principal, and superintendent years of experience. A review of the literature…

Explaining the moon illusion

PubMed Central

Kaufman, Lloyd; Kaufman, James H.

2000-01-01

An old explanation of the moon illusion holds that various cues place the horizon moon at an effectively greater distance than the elevated moon. Although both moons have the same angular size, the horizon moon must be perceived as larger. More recent explanations hold that differences in accommodation or other factors cause the elevated moon to appear smaller. As a result of this illusory difference in size, the elevated moon appears to be more distant than the horizon moon. These two explanations, both based on the geometry of stereopsis, lead to two diametrically opposed hypotheses. That is, a depth interval at a long distance is associated with a smaller binocular disparity, whereas an equal depth interval at a smaller distance is associated with a larger disparity. We conducted experiments involving artificial moons and confirmed the hypothesis that the horizon moon is at a greater perceptual distance. Moreover, when a moon of constant angular size was moved closer it was also perceived as growing smaller, which is consistent with the older explanation. Although Emmert's law does not predict the size–distance relationship over long distances, we conclude that the horizon moon is perceived as larger because the perceptual system treats it as though it is much farther away. Finally, we observe that recent explanations substitute perceived size for angular size as a cue to distance. Thus, they imply that perceptions cause perceptions. PMID:10618447

Perception of health from facial cues

PubMed Central

Henderson, Audrey J.; Holzleitner, Iris J.; Talamas, Sean N.

2016-01-01

Impressions of health are integral to social interactions, yet poorly understood. A review of the literature reveals multiple facial characteristics that potentially act as cues to health judgements. The cues vary in their stability across time: structural shape cues including symmetry and sexual dimorphism alter slowly across the lifespan and have been found to have weak links to actual health, but show inconsistent effects on perceived health. Facial adiposity changes over a medium time course and is associated with both perceived and actual health. Skin colour alters over a short time and has strong effects on perceived health, yet links to health outcomes have barely been evaluated. Reviewing suggested an additional influence of demeanour as a perceptual cue to health. We, therefore, investigated the association of health judgements with multiple facial cues measured objectively from two-dimensional and three-dimensional facial images. We found evidence for independent contributions of face shape and skin colour cues to perceived health. Our empirical findings: (i) reinforce the role of skin yellowness; (ii) demonstrate the utility of global face shape measures of adiposity; and (iii) emphasize the role of affect in facial images with nominally neutral expression in impressions of health. PMID:27069057

Effect of downed woody debris on small mammal anti-predator behavior.

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

Hinkleman, Travis, M.; Orrock, John, L.; Loeb, Susan, C.

2011-10-01

Anti-predator behavior can affect prey growth, reproduction, survival, and generate emergent effects in food webs. Small mammals often lower the cost of predation by altering their behavior in response to shrubs,but the importance of other microhabitat features, such as downed woody debris, for anti-predator behavior is unknown. We used givingup densities to quantify the degree to which downed woody debris alters perceived predation risk by small mammals in southeastern pineforests. We placed 14 foraging trays next to large downed woody debris,shrubs, and in open areas for 12 consecutive nights. Moon illumination, a common indicator of predation risk, led to amore » similar reduction in small mammal foraging in all three microhabitats (open, downed woody debris,and shrub). Small mammals perceived open microhabitats as riskier than shrub microhabitats, with downed woody debris habitats perceived as being of intermediate risk between shrub and open microhabitats. Despite the presumed benefits of the protective cover of downed woody debris, small mammals may perceive downed woody debris as a relatively risky foraging site in southeastern pine forests where the high diversity and abundance of rodent-eating snakes may provide a primary predatory threat.« less

Decisions to shoot in a weapon identification task: The influence of cultural stereotypes and perceived threat on false positive errors.

PubMed

Fleming, Kevin K; Bandy, Carole L; Kimble, Matthew O

2010-01-01

The decision to shoot a gun engages executive control processes that can be biased by cultural stereotypes and perceived threat. The neural locus of the decision to shoot is likely to be found in the anterior cingulate cortex (ACC), where cognition and affect converge. Male military cadets at Norwich University (N=37) performed a weapon identification task in which they made rapid decisions to shoot when images of guns appeared briefly on a computer screen. Reaction times, error rates, and electroencephalogram (EEG) activity were recorded. Cadets reacted more quickly and accurately when guns were primed by images of Middle-Eastern males wearing traditional clothing. However, cadets also made more false positive errors when tools were primed by these images. Error-related negativity (ERN) was measured for each response. Deeper ERNs were found in the medial-frontal cortex following false positive responses. Cadets who made fewer errors also produced deeper ERNs, indicating stronger executive control. Pupil size was used to measure autonomic arousal related to perceived threat. Images of Middle-Eastern males in traditional clothing produced larger pupil sizes. An image of Osama bin Laden induced the largest pupil size, as would be predicted for the exemplar of Middle East terrorism. Cadets who showed greater increases in pupil size also made more false positive errors. Regression analyses were performed to evaluate predictions based on current models of perceived threat, stereotype activation, and cognitive control. Measures of pupil size (perceived threat) and ERN (cognitive control) explained significant proportions of the variance in false positive errors to Middle-Eastern males in traditional clothing, while measures of reaction time, signal detection response bias, and stimulus discriminability explained most of the remaining variance.

The impact of coercion on services from the perspective of mental health care consumers with co-occurring disorders.

PubMed

Stanhope, Victoria; Marcus, Steven; Solomon, Phyllis

2009-02-01

Disengagement from services by people with serious mental illnesses continues to be a major challenge for the mental health system. Assertive community treatment combined with Housing First services is an intervention targeted toward consumers whom the system has failed to engage. The processes involved in engaging and maintaining consumers in mental health services play an important role but remain an understudied aspect of the intervention. This study examined the social interaction between consumers and case managers from the perspective of consumers. Seventy service contacts between unique consumer-case manager dyads were sampled. Consumers with co-occurring serious mental illness and substance use disorders completed interviews after each service contact. They provided information on sociodemographic characteristics, service contact characteristics, consumer-provider relationship, utilization of coercive strategies, perceived coercion, and service contact evaluation. Multivariate regression analyses examined the association of consumer-provider relationship and perceived coercion with service contact evaluation. Consumer-provider relationship was negatively associated with perceived coercion (effect size=.08). Perceived coercion was negatively associated with service contact evaluation (effect size=.34). Perceived coercion was positively associated with time in the program (effect size=.17) and negatively associated with length of the service contact (effect size=.14). Effect sizes ranging from .08 to .34 are typically considered small to medium. Findings demonstrate that for consumers, a positive response to service contacts indicated that they did not feel coerced. With consumers whose connection to services is tenuous, an immediate positive response to service contacts may be vital to maintain engagement. Research is needed to identify supportive case manager strategies that facilitate relationship building.

Decisions to Shoot in a Weapon Identification Task: The Influence of Cultural Stereotypes and Perceived Threat on False Positive Errors

PubMed Central

Fleming, Kevin K.; Bandy, Carole L.; Kimble, Matthew O.

2014-01-01

The decision to shoot engages executive control processes that can be biased by cultural stereotypes and perceived threat. The neural locus of the decision to shoot is likely to be found in the anterior cingulate cortex (ACC) where cognition and affect converge. Male military cadets at Norwich University (N=37) performed a weapon identification task in which they made rapid decisions to shoot when images of guns appeared briefly on a computer screen. Reaction times, error rates, and EEG activity were recorded. Cadets reacted more quickly and accurately when guns were primed by images of middle-eastern males wearing traditional clothing. However, cadets also made more false positive errors when tools were primed by these images. Error-related negativity (ERN) was measured for each response. Deeper ERN’s were found in the medial-frontal cortex following false positive responses. Cadets who made fewer errors also produced deeper ERN’s, indicating stronger executive control. Pupil size was used to measure autonomic arousal related to perceived threat. Images of middle-eastern males in traditional clothing produced larger pupil sizes. An image of Osama bin Laden induced the largest pupil size, as would be predicted for the exemplar of Middle East terrorism. Cadets who showed greater increases in pupil size also made more false positive errors. Regression analyses were performed to evaluate predictions based on current models of perceived threat, stereotype activation, and cognitive control. Measures of pupil size (perceived threat) and ERN (cognitive control) explained significant proportions of the variance in false positive errors to middle-eastern males in traditional clothing, while measures of reaction time, signal detection response bias, and stimulus discriminability explained most of the remaining variance. PMID:19813139

Does perceived race affect discrimination and recognition of ambiguous-race faces? A test of the sociocognitive hypothesis.

PubMed

Rhodes, Gillian; Lie, Hanne C; Ewing, Louise; Evangelista, Emma; Tanaka, James W

2010-01-01

Discrimination and recognition are often poorer for other-race than own-race faces. These other-race effects (OREs) have traditionally been attributed to reduced perceptual expertise, resulting from more limited experience, with other-race faces. However, recent findings suggest that sociocognitive factors, such as reduced motivation to individuate other-race faces, may also contribute. If the sociocognitive hypothesis is correct, then it should be possible to alter discrimination and memory performance for identical faces by altering their perceived race. We made identical ambiguous-race morphed faces look either Asian or Caucasian by presenting them in Caucasian or Asian face contexts, respectively. However, this perceived-race manipulation had no effect on either discrimination (Experiment 1) or memory (Experiment 2) for the ambiguous-race faces, despite the presence of the usual OREs in discrimination and recognition of unambiguous Asian and Caucasian faces in our participant population. These results provide no support for the sociocognitive hypothesis. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

Psychosocial correlates of the perceived stigma of problem drinking in the workplace.

PubMed

Reynolds, G Shawn; Lehman, Wayne E K; Bennett, Joel B

2008-07-01

The purpose of this study was to evaluate a questionnaire assessment of the perceived stigma of problem drinking that was designed for use in workplace substance abuse prevention research. Municipal employees from a mid-sized city (n = 315) and a large-sized city (n = 535) completed questionnaire measures of perceived coworker stigmatization of problem drinking, drinking levels, substance-use policy attitudes, workgroup stress and interdependence, alcohol-tolerance norms, and demographic variables. Inter-item correlation coefficients showed that the measure of the stigma of problem drinking had good internal consistency reliability (.76) in both samples. Hierarchical regression analyses showed that higher education, abstinence from alcohol, stress, and perceived temperance norms were all uniquely correlated with perceived stigma. Women and men perceived the same level of stigma from coworkers. Editors' Strategic Implications: This brief, validated measure provides organizations with a way to assess the level of stigma attached to alcohol abuse in their workplace culture, thereby enabling the organization to target and promote effective strategies to decrease the stigma attached to seeking help with the goal of reducing alcohol abuse.

Perceiving the present and a systematization of illusions.

PubMed

Changizi, Mark A; Hsieh, Andrew; Nijhawan, Romi; Kanai, Ryota; Shimojo, Shinsuke

2008-04-05

Over the history of the study of visual perception there has been great success at discovering countless visual illusions. There has been less success in organizing the overwhelming variety of illusions into empirical generalizations (much less explaining them all via a unifying theory). Here, this article shows that it is possible to systematically organize more than 50 kinds of illusion into a 7 × 4 matrix of 28 classes. In particular, this article demonstrates that (1) smaller sizes, (2) slower speeds, (3) greater luminance contrast, (4) farther distance, (5) lower eccentricity, (6) greater proximity to the vanishing point, and (7) greater proximity to the focus of expansion all tend to have similar perceptual effects, namely, to (A) increase perceived size, (B) increase perceived speed, (C) decrease perceived luminance contrast, and (D) decrease perceived distance. The detection of these empirical regularities was motivated by a hypothesis, called "perceiving the present," that the visual system possesses mechanisms for compensating neural delay during forward motion. This article shows how this hypothesis predicts the empirical regularity. 2008 Cognitive Science Society, Inc.

Canine substitution for missing maxillary lateral incisors: the influence of canine morphology, size, and shade on perceptions of smile attractiveness.

PubMed

Brough, Elaine; Donaldson, Ana Nora; Naini, Farhad B

2010-12-01

This study was conducted to determine whether variations in the morphology, size, or shade of maxillary canines would influence perceptions of smile attractiveness in patients with canines substituted for missing maxillary lateral incisors. A smiling photograph of a hypodontia patient who had had orthodontic space closure with maxillary canines replacing the lateral incisors was digitally modified to create a bilaterally symmetrical image. Four groups of images were created, digitally altering canine gingival height, crown tip height, canine width, and canine shade. Three groups of judges (40 orthodontists, 40 dentists, and 40 laypeople) ranked the images for smile attractiveness, also scoring the most and the least attractive of each of the 4 groups, and the most and least attractive of all images. Canine gingival height was the most attractive 0.5 mm below the gingival margin of the maxillary central incisor and progressively less attractive with increasing gingival height. Increasing canine width, increased canine tip height, and pointed canines were perceived to be unattractive. Brighter than normal shades of canines were preferred to darker shades. Narrow canine crowns were most frequently ranked as the most attractive overall, 1.5 mm narrower was preferred by the orthodontists and dentists, and 3.0 mm narrower was preferred by the laypeople. All 3 groups ranked the darkest image, 20 times darker than the original, most frequently as the least attractive image overall. There was good general agreement between orthodontists, dentists, and laypeople for all 4 parameters of smile attractiveness, although laypeople demonstrated greater intragroup variations. The morphology, size, and shade of the maxillary canine in patients having orthodontic space closure and lateral incisor substitution can have a marked effect on perceived smile attractiveness. Copyright © 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Art as Alterity in Education

ERIC Educational Resources Information Center

Zhao, Guoping

2014-01-01

In education, art has often been perceived as entertainment and decoration and is the first subject to go when there are budget cuts or test-score pressures. Drawing on Emmanuel Lévinas's idea of the primacy of radical alterity that breaks the totality of our being, enables self-transformation and ethics, and ensures community as a totality…

Power Moves Beyond Complementarity: A Staring Look Elicits Avoidance in Low Power Perceivers and Approach in High Power Perceivers

PubMed Central

Weick, Mario; McCall, Cade; Blascovich, Jim

2017-01-01

Sustained, direct eye-gaze—staring—is a powerful cue that elicits strong responses in many primate and nonprimate species. The present research examined whether fleeting experiences of high and low power alter individuals’ spontaneous responses to the staring gaze of an onlooker. We report two experimental studies showing that sustained, direct gaze elicits spontaneous avoidance tendencies in low power perceivers and spontaneous approach tendencies in high power perceivers. These effects emerged during interactions with different targets and when power was manipulated between-individuals (Study 1) and within-individuals (Study 2), thus attesting to a high degree of flexibility in perceivers’ reactions to gaze cues. Together, the present findings indicate that power can break the cycle of complementarity in individuals’ spontaneous responding: Low power perceivers complement and move away from, and high power perceivers reciprocate and move toward, staring onlookers. PMID:28903712

Disclaimer labels on fashion magazine advertisements: Does timing of digital alteration information matter?

PubMed

Bury, Belinda; Tiggemann, Marika; Slater, Amy

2017-04-01

The study aimed to investigate whether a message informing readers about digital alteration read before exposure to thin ideal advertisements would enhance the effectiveness of disclaimer labels. Participants were 280 female undergraduate students who viewed eleven thin ideal fashion magazine advertisements. Half viewed the advertisements in their original format, and half viewed the same advertisements with a digital alteration disclaimer label. Prior to viewing the advertisements, participants read either a brief message informing them that advertisements are commonly digitally altered, or a control message. Irrespective of experimental condition, exposure to the thin ideal advertisements led to increased body dissatisfaction, with social comparison predicting this increase. Neither the disclaimer label nor the pre-exposure message, nor their combination, led to reductions in perceived realism, social comparison, or body dissatisfaction. However, trait appearance comparison moderated the effect of pre-exposure message on perceived realism, such that women high on trait appearance comparison in the digital alteration pre-exposure message condition rated the models as relatively more realistic than did women low on this trait. It was concluded that more research is needed to identify brief and easy-to-implement universal prevention strategies that can reduce the negative effects of thin ideal media imagery on women's body image. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparing esthetic smile perceptions among laypersons with and without orthodontic treatment experience and dentists

PubMed Central

An, Seong-Mu; Choi, Sun-Young; Chung, Young-Wook; Jang, Tae-Ho

2014-01-01

Objective The purpose of this study was to examine whether orthodontic treatment experience affects the individual's perception of smile esthetics and to evaluate differences among orthodontically treated laypersons, non-treated laypersons, and dentists by using computerized image alterations. Methods A photograph of a woman's smile was digitally altered using a software image editing program. The alterations involved gingival margin height, crown width and length, incisal plane canting, and dental midline of the maxillary anterior teeth. Three groups of raters (orthodontically treated laypersons, non-treated laypersons, and dentists) evaluated the original and altered images using a visual analog scale. Results The threshold for detecting changes in maxillary central incisor gingival margin height among laypersons was 1.5 mm; the threshold of dentists, who were more perceptive, was 1.0 mm. For maxillary lateral incisor crown width and height, the threshold of all three groups was 3.0 mm. Canting of the incisal plane was perceived when the canting was 3.0 mm among non-treated laypersons, 2.0 mm among treated laypersons, and 1.0 mm among dentists. Non-treated laypersons could not perceive dental midline shifts; however, treated laypersons and dentists perceived them when the shift was ≥ 3.0 mm. Conclusions Laypersons with and without orthodontic treatment experience and dentists have different perceptions of smile esthetics. Orthodontically treated laypersons were more critical than non-treated laypersons regarding incisal plane canting and dental midline shifts. Based on these findings, it is suggested that orthodontic treatment experience improved the esthetic perceptions of laypersons. PMID:25473645

Relative size perception at a distance is best at eye level

NASA Technical Reports Server (NTRS)

Bertamini, M.; Yang, T. L.; Proffitt, D. R.; Kaiser, M. K. (Principal Investigator)

1998-01-01

Relative size judgments were collected for two objects at 30.5 m and 23.8 from the observer in order to assess how performance depends on the relationship between the size of the objects and the eye level of the observer. In three experiments in an indoor hallway and in one experiment outdoors, accuracy was higher for objects in the neighborhood of eye level. We consider these results in the light of two hypotheses. One proposes that observers localize the horizon as a reference for judging relative size, and the other proposes that observers perceive the general neighborhood of the horizon and then employ a height-in-visual-field heuristic. The finding that relative size judgments are best around the horizon implies that information that is independent of distance perception is used in perceiving size.

Relationships among Perceived Stress, Coping, and Grade Point Average in University Students

ERIC Educational Resources Information Center

Kewallal, Rajendra David

2013-01-01

This study explored the relationships among perceived stress, coping style, and academic performance in 210 students from a mid-sized public university and a small private college. Study participants were asked to complete the Perceived Stress Scale, the Brief COPE Questionnaire, and a demographic survey asking about their age, gender, grade point…

Body size preference and body weight perception among two migrant groups of non-Western origin.

PubMed

Nicolaou, Mary; Doak, Colleen; Dam, Rob van; Hosper, Karen; Seidell, Jaap; Stronks, Karien

2008-12-01

To evaluate body size preference, body weight perception and their relationship with actual weight in two migrant groups of non-Western origin, Turks and Moroccans; additionally, to study the association between body size preference and acculturation. Cross-sectional study. Amsterdam, The Netherlands. Males and females (18-30 years) were randomly selected from the population registry (n 451); participants, or at least one of their parents, were born in Turkey or Morocco. Body size preference was assessed using seven silhouette drawings and body weight perception was assessed by asking participants' opinion of own weight. Acculturation variables were generation status and two scale measures, cultural orientation and social contacts. Participants showed preference for a thin body size. The discrepancy between ideal and current size was significant in women but not men (P < 0.001). Perceived current body size was correlated with BMI (Spearman's correlation coefficient 0.60, P < 0.001 (men) and 0.73, P < 0.001 (women)). Among overweight participants (BMI = 25.0-29.9 kg/m2), 63-82 % of men and 35 % of women perceived themselves as 'average'. Paying attention to own body weight was associated with a discrepancy between ideal and current size among women and with perceiving oneself as 'overweight' among men. Body size preference was not significantly associated with the three acculturation variables. We did not observe a preference for large body sizes in these two non-Western migrant groups. Similar to Western populations, most women wished to be thinner than they were. This was not the case among men, the majority of whom were also unaware of being overweight.

Emotion and Perception: The Role of Affective Information

PubMed Central

Zadra, Jonathan R.; Clore, Gerald L.

2011-01-01

Visual perception and emotion are traditionally considered separate domains of study. In this article, however, we review research showing them to be less separable that usually assumed. In fact, emotions routinely affect how and what we see. Fear, for example, can affect low-level visual processes, sad moods can alter susceptibility to visual illusions, and goal-directed desires can change the apparent size of goal-relevant objects. In addition, the layout of the physical environment, including the apparent steepness of a hill and the distance to the ground from a balcony can both be affected by emotional states. We propose that emotions provide embodied information about the costs and benefits of anticipated action, information that can be used automatically and immediately, circumventing the need for cogitating on the possible consequences of potential actions. Emotions thus provide a strong motivating influence on how the environment is perceived. PMID:22039565

Body dissatisfaction and the wish for different silhouette is associated with higher adiposity and fat intake in female ballet dancers than male.

PubMed

Da Silva, Camila Lacerda; De Oliveira, Erick Prado; De Sousa, Maysa Vieira; Pimentel, Gustavo D

2016-01-01

It is known that behavioral disorders and altered food intake are linked to ballet dancers. Thus, the aim of the present study was to investigate the body composition, dietetic profile, self-perceived body image and social desirability in professional ballet dancers. This study was conducted from April to October 2010 in athletes screened for nutritional evaluation. Anthropometric, dietary, social desirability and self-perceived body image evaluation were performed to attend the aim of study. We found that ballet dancers are highly trained and eutrophic, although female dancers had higher adiposity and fat intake than male dancers. In addition, it was observed low consumption of calcium, dietary fiber, potassium, magnesium and vitamin A. Moreover, 30% of male ballet dancers have a strong desire for social acceptance. When the body image was evaluated by Body Shape Questionnaire (BSQ), was reported that 40% of the ballet female dancers have of moderate to severe alteration in body image and 20% of male dancers had slight alteration. Furthermore, the Drawings and Silhouettes Scale showed that 80% of male dancers wish to have a smaller or larger silhouette than the current self-perceived and 60% of the female dancers would like to have a silhouette lower than the self-perceive as current. Collectively, our results shown that most of the dancers were eutrophic, but female athletes have higher adiposity and present strong desire for a different shape of current. Furthermore, was found increased fat intake in female group; however, deficiencies in consumption of dietary fiber, calcium, potassium, magnesium and vitamin A were found in both gender.

The influence of varying maxillary lateral incisor dimensions on perceived smile aesthetics.

PubMed

Bukhary, S M N; Gill, D S; Tredwin, C J; Moles, D R

2007-12-22

The aim of this study was to determine the influence of varying the dimensions of the maxillary lateral incisors on perceived smile aesthetics. Clinical study. Postgraduate dental teaching hospital. A photograph of a female smile displaying only the lips and teeth was digitally altered. First, the width of the maxillary lateral incisors, in proportion to the central incisor, was altered at 5% intervals to produce six images (52%, 57%, 62% [the 'golden proportion'], 67%, 72% and 77%). In a second group, the length of the lateral incisor was altered at 0.5 mm increments to produce five images with the lateral incisor 0.5 mm, 1 mm, 1.5 mm, 2 mm and 2.5 mm shorter than the adjacent central incisor. The photos were ranked from 'most attractive' to 'least attractive' by 41 hypodontia patients, 46 non-hypodontia 'control' patients and 30 dentists. The 67% followed by the 72% lateral-to-central width proportions were the 'most preferred' by all groups. A maxillary lateral incisor that is 1-1.5 mm shorter than the central incisor was the 'most popular' maxillary lateral incisor length. The very short and very long maxillary lateral incisor was consistently perceived as 'least attractive'. There is no evidence to suggest that the golden proportion should be considered the ideal aesthetic standard when creating space for the replacement of missing lateral incisors.

The influence of social support and perceived stress on response time inconsistency.

PubMed

Phibbs, Sandi; Stawski, Robert S; MacDonald, Stuart W S; Munoz, Elizabeth; Smyth, Joshua M; Sliwinski, Martin J

2017-11-24

Lack of social support and high levels of stress represent potentially modifiable risk factors for cognitive aging. In this study we examined the relationships between these two risk factors and response time inconsistency (RTI), or trial-to-trial variability in choice response time tasks. RTI is an early indicator of declining cognitive health, and examining the influence of modifiable psychosocial risk factors on RTI is important for understanding and promoting cognitive health during adulthood and old age. Using data from a community sample study (n = 317; M age = 49, range = 19-83), we examined the effects of social support, including size of network and satisfaction with support, global perceived stress, and their interactions on RTI. Neither size of network nor satisfaction with support was associated with RTI independent of perceived stress. Stress was positively associated with increased RTI on all tasks, independent of social support. Perceived stress did not interact with either dimension of social support to predict RTI, and perceived stress effects were invariant across age and sex. Perceived stress, but not social support, may be a unique and modifiable risk factor for normal and pathological cognitive aging. Discussion focuses on the importance of perceived stress and its impact on RTI in supporting cognitive health in adulthood and old age.

Inspiration or deflation? Feeling similar or dissimilar to slim and plus-size models affects self-evaluation of restrained eaters.

PubMed

Papies, Esther K; Nicolaije, Kim A H

2012-01-01

The present studies examined the effect of perceiving images of slim and plus-size models on restrained eaters' self-evaluation. While previous research has found that such images can lead to either inspiration or deflation, we argue that these inconsistencies can be explained by differences in perceived similarity with the presented model. The results of two studies (ns=52 and 99) confirmed this and revealed that restrained eaters with high (low) perceived similarity to the model showed more positive (negative) self-evaluations when they viewed a slim model, compared to a plus-size model. In addition, Study 2 showed that inducing in participants a similarities mindset led to more positive self-evaluations after viewing a slim compared to a plus-size model, but only among restrained eaters with a relatively high BMI. These results are discussed in the context of research on social comparison processes and with regard to interventions for protection against the possible detrimental effects of media images. Copyright © 2011 Elsevier Ltd. All rights reserved.

Assessment of body perception among Swedish adolescents and young adults.

PubMed

Bergström, E; Stenlund, H; Svedjehäll, B

2000-01-01

To assess body perception in adolescents and young adults without anorexia nervosa. Using a visual size estimation technique, perceived body size was estimated in four groups of Swedish adolescents and young adults without anorexia nervosa (86 males and 95 females). Perceived body size was estimated at nine different body sites comparing these estimations to real body size. The results show that 95% of males and 96% of females overestimated their body size (mean overestimation: males +22%, females +33%). The overestimations were greatest in females. The greatest overestimations were made of the waist (males +31%, females +46%), buttocks (males +22%, females +42%), and thighs (males +27%, females +41%). The results indicate that overestimation of body size may be a general phenomenon in adolescents and young adults in a country such as Sweden, implying a similar, but less pronounced distortion of body image as in individuals with anorexia nervosa.

Do domestic dogs (Canis lupus familiaris) perceive the Delboeuf illusion?

PubMed

Miletto Petrazzini, Maria Elena; Bisazza, Angelo; Agrillo, Christian

2017-05-01

In the last decade, visual illusions have been repeatedly used as a tool to compare visual perception among species. Several studies have investigated whether non-human primates perceive visual illusions in a human-like fashion, but little attention has been paid to other mammals, and sensitivity to visual illusions has been never investigated in the dog. Here, we studied whether domestic dogs perceive the Delboeuf illusion. In human and non-human primates, this illusion creates a misperception of item size as a function of its surrounding context. To examine this effect in dogs, we adapted the spontaneous preference paradigm recently used with chimpanzees. Subjects were presented with two plates containing food. In control trials, two different amounts of food were presented in two identical plates. In this circumstance, dogs were expected to select the larger amount. In test trials, equal food portion sizes were presented in two plates differing in size: if dogs perceived the illusion as primates do, they were expected to select the amount of food presented in the smaller plate. Dogs significantly discriminated the two alternatives in control trials, whereas their performance did not differ from chance in test trials with the illusory pattern. The fact that dogs do not seem to be susceptible to the Delboeuf illusion suggests a potential discontinuity in the perceptual biases affecting size judgments between primates and dogs.

Effect of the retinal size of a peripheral cue on attentional orienting in two- and three-dimensional worlds.

PubMed

Jiang, Yizhou; Li, Sijie; Li, You; Zeng, Hang; Chen, Qi

2016-07-01

It has been documented that due to limited attentional resources, the size of the attentional focus is inversely correlated with processing efficiency. Moreover, by adopting a variety of two-dimensional size illusions induced by pictorial depth cues (e.g., the Ponzo illusion), previous studies have revealed that the perceived, rather than the retinal, size of an object determines its detection. It remains unclear, however, whether and how the retinal versus perceived size of a cue influences the process of attentional orienting to subsequent targets, and whether the corresponding influencing processes differ between two-dimensional (2-D) and three-dimensional (3-D) space. In the present study, we incorporated the dot probe paradigm with either a 2-D Ponzo illusion, induced by pictorial depth cues, or a virtual 3-D world in which the Ponzo illusion turned into visual reality. By varying the retinal size of the cue while keeping its perceived size constant (Exp. 1), we found that a cue with smaller retinal size significantly facilitated attentional orienting as compared to a cue with larger retinal size, and that the effects were comparable between 2-D and 3-D displays. Furthermore, when the pictorial background was removed and the cue display was positioned in either the farther or the closer depth plane (Exp. 2), or when both the depth and the background were removed (Exp. 3), the retinal size, rather than the depth, of the cue still affected attentional orienting. Taken together, our results suggest that the retinal size of a cue plays the crucial role in the visuospatial orienting of attention in both 2-D and 3-D.

Differential Gender Effects in the Relationship between Perceived Immune Functioning and Autistic Traits.

PubMed

Mackus, Marlou; Kruijff, Deborah de; Otten, Leila S; Kraneveld, Aletta D; Garssen, Johan; Verster, Joris C

2017-04-12

Altered immune functioning has been demonstrated in individuals with autism spectrum disorder (ASD). The current study explores the relationship between perceived immune functioning and experiencing ASD traits in healthy young adults. N = 410 students from Utrecht University completed a survey on immune functioning and autistic traits. In addition to a 1-item perceived immune functioning rating, the Immune Function Questionnaire (IFQ) was completed to assess perceived immune functioning. The Dutch translation of the Autism-Spectrum Quotient (AQ) was completed to examine variation in autistic traits, including the domains "social insights and behavior", "difficulties with change", "communication", "phantasy and imagination", and "detail orientation". The 1-item perceived immune functioning score did not significantly correlate with the total AQ score. However, a significant negative correlation was found between perceived immune functioning and the AQ subscale "difficulties with change" (r = -0.119, p = 0.019). In women, 1-item perceived immune functioning correlated significantly with the AQ subscales "difficulties with change" (r = -0.149, p = 0.029) and "communication" (r = -0.145, p = 0.032). In men, none of the AQ subscales significantly correlated with 1-item perceived immune functioning. In conclusion, a modest relationship between perceived immune functioning and several autistic traits was found.

Larger Stimuli Require Longer Processing Time for Perception.

PubMed

Kanai, Ryota; Dalmaijer, Edwin S; Sherman, Maxine T; Kawakita, Genji; Paffen, Chris L E

2017-05-01

The time it takes for a stimulus to reach awareness is often assessed by measuring reaction times (RTs) or by a temporal order judgement (TOJ) task in which perceived timing is compared against a reference stimulus. Dissociations of RT and TOJ have been reported earlier in which increases in stimulus intensity such as luminance intensity results in a decrease of RT, whereas perceived perceptual latency in a TOJ task is affected to a lesser degree. Here, we report that a simple manipulation of stimulus size has stronger effects on perceptual latency measured by TOJ than on motor latency measured by RT tasks. When participants were asked to respond to the appearance of a simple stimulus such as a luminance blob, the perceptual latency measured against a standard reference stimulus was up to 40 ms longer for a larger stimulus. In other words, the smaller stimulus was perceived to occur earlier than the larger one. RT on the other hand was hardly affected by size. The TOJ results were further replicated in a simultaneity judgement task, suggesting that the effects of size are not due to TOJ-specific response biases but more likely reflect an effect on perceived timing.

Metabolic cost and mechanics of walking in women with fibromyalgia syndrome.

PubMed

MacPhee, Renée S; McFall, Kristen; Perry, Stephen D; Tiidus, Peter M

2013-10-18

Fibromyalgia syndrome (FS) is characterized by the presence of widespread pain, fatigue, muscle weakness and reduced work capacity. Previous research has demonstrated that women with fibromyalgia have altered walking (gait) patterns, which may be a consequence of muscular pain. This altered gait is characterized by greater reliance on hip flexors rather than ankle plantar flexors and resembles gait patterns seen in normal individuals walking at higher speeds, suggesting that gait of individuals with fibromyalgia may be less efficient.This study compared rates of energy expenditure of 6 females with FS relative to 6 normal, age and weight matched controls, at various walking speeds on a motorized treadmill. Metabolic measurements including V02 (ml/kg/min), respirations, heart rate and calculated energy expenditures as well as the Borg Scale of Perceived Exertion scale ratings were determined at baseline and for 10 min while walking at each of 2, 4 and 5 km/hour on 1% grade. Kinematic recordings of limb and body movements while treadmill walking and separate measurements of ground reaction forces while walking over ground were also determined. In addition, all subjects completed the RAND 36-Item Health Survey (1.0). Gait analysis results were similar to previous reports of altered gait patterns in FS females. Despite noticeable differences in gait patterns, no significant differences (p > 0.05) existed between the FS and control subjects on any metabolic measures at any walking speed. Total number of steps taken was also similar between groups. Ratings on the Borg Scale of Perceived Exertion, the RAND and self-reported levels of pain indicated significantly greater (p < 0.05) perceived effort and pain in FS subjects relative to control subjects during walking and daily activities. The altered gait patterns and greater perceptions of effort and pain did not significantly increase the metabolic costs of walking in women with FS and hence, increased sensations of fatigue in FS women may not be related to alteration in metabolic cost of ambulation.

Metabolic cost and mechanics of walking in women with fibromyalgia syndrome

PubMed Central

2013-01-01

Background Fibromyalgia syndrome (FS) is characterized by the presence of widespread pain, fatigue, muscle weakness and reduced work capacity. Previous research has demonstrated that women with fibromyalgia have altered walking (gait) patterns, which may be a consequence of muscular pain. This altered gait is characterized by greater reliance on hip flexors rather than ankle plantar flexors and resembles gait patterns seen in normal individuals walking at higher speeds, suggesting that gait of individuals with fibromyalgia may be less efficient. This study compared rates of energy expenditure of 6 females with FS relative to 6 normal, age and weight matched controls, at various walking speeds on a motorized treadmill. Metabolic measurements including V02 (ml/kg/min), respirations, heart rate and calculated energy expenditures as well as the Borg Scale of Perceived Exertion scale ratings were determined at baseline and for 10 min while walking at each of 2, 4 and 5 km/hour on 1% grade. Kinematic recordings of limb and body movements while treadmill walking and separate measurements of ground reaction forces while walking over ground were also determined. In addition, all subjects completed the RAND 36-Item Health Survey (1.0). Findings Gait analysis results were similar to previous reports of altered gait patterns in FS females. Despite noticeable differences in gait patterns, no significant differences (p > 0.05) existed between the FS and control subjects on any metabolic measures at any walking speed. Total number of steps taken was also similar between groups. Ratings on the Borg Scale of Perceived Exertion, the RAND and self-reported levels of pain indicated significantly greater (p < 0.05) perceived effort and pain in FS subjects relative to control subjects during walking and daily activities. Conclusions The altered gait patterns and greater perceptions of effort and pain did not significantly increase the metabolic costs of walking in women with FS and hence, increased sensations of fatigue in FS women may not be related to alteration in metabolic cost of ambulation. PMID:24139565

Rapid Simultaneous Enhancement of Visual Sensitivity and Perceived Contrast during Saccade Preparation

PubMed Central

Rolfs, Martin; Carrasco, Marisa

2012-01-01

Humans and other animals with foveate vision make saccadic eye movements to prioritize the visual analysis of behaviorally relevant information. Even before movement onset, visual processing is selectively enhanced at the target of a saccade, presumably gated by brain areas controlling eye movements. Here we assess concurrent changes in visual performance and perceived contrast before saccades, and show that saccade preparation enhances perception rapidly, altering early visual processing in a manner akin to increasing the physical contrast of the visual input. Observers compared orientation and contrast of a test stimulus, appearing briefly before a saccade, to a standard stimulus, presented previously during a fixation period. We found simultaneous progressive enhancement in both orientation discrimination performance and perceived contrast as time approached saccade onset. These effects were robust as early as 60 ms after the eye movement was cued, much faster than the voluntary deployment of covert attention (without eye movements), which takes ~300 ms. Our results link the dynamics of saccade preparation, visual performance, and subjective experience and show that upcoming eye movements alter visual processing by increasing the signal strength. PMID:23035086

A multi-level analysis of the effects of age and gender stereotypes on trust in anthropomorphic technology by younger and older adults.

PubMed

Pak, Richard; McLaughlin, Anne Collins; Bass, Brock

2014-01-01

Previous research has shown that gender stereotypes, elicited by the appearance of the anthropomorphic technology, can alter perceptions of system reliability. The current study examined whether stereotypes about the perceived age and gender of anthropomorphic technology interacted with reliability to affect trust in such technology. Participants included a cross-section of younger and older adults. Through a factorial survey, participants responded to health-related vignettes containing anthropomorphic technology with a specific age, gender, and level of past reliability by rating their trust in the system. Trust in the technology was affected by the age and gender of the user as well as its appearance and reliability. Perceptions of anthropomorphic technology can be affected by pre-existing stereotypes about the capability of a specific age or gender. The perceived age and gender of automation can alter perceptions of the anthropomorphic technology such as trust. Thus, designers of automation should design anthropomorphic interfaces with an awareness that the perceived age and gender will interact with the user’s age and gender

Illusory Changes in Body Size Modulate Body Satisfaction in a Way That Is Related to Non-Clinical Eating Disorder Psychopathology

PubMed Central

Preston, Catherine; Ehrsson, H. Henrik

2014-01-01

Historically, body size overestimation has been linked to abnormal levels of body dissatisfaction found in eating disorders. However, recently this relationship has been called into question. Indeed, despite a link between how we perceive and how we feel about our body seeming intuitive, until now lack of an experimental method to manipulate body size has meant that a causal link, even in healthy participants, has remained elusive. Recent developments in body perception research demonstrate that the perceptual experience of the body can be readily manipulated using multisensory illusions. The current study exploits such illusions to modulate perceived body size in an attempt to influence body satisfaction. Participants were presented with stereoscopic video images of slimmer and wider mannequin bodies viewed through head-mounted displays from first person perspective. Illusory ownership was induced by synchronously stroking the seen mannequin body with the unseen real body. Pre and post-illusion affective and perceptual measures captured changes in perceived body size and body satisfaction. Illusory ownership of a slimmer body resulted in participants perceiving their actual body as slimmer and giving higher ratings of body satisfaction demonstrating a direct link between perceptual and affective body representations. Change in body satisfaction following illusory ownership of a wider body, however, was related to degree of (non-clinical) eating disorder psychopathology, which can be linked to fluctuating body representations found in clinical samples. The results suggest that body perception is linked to body satisfaction and may be of importance for eating disorder symptomology. PMID:24465698

A mass-density model can account for the size-weight illusion

PubMed Central

Bergmann Tiest, Wouter M.; Drewing, Knut

2018-01-01

When judging the heaviness of two objects with equal mass, people perceive the smaller and denser of the two as being heavier. Despite the large number of theories, covering bottom-up and top-down approaches, none of them can fully account for all aspects of this size-weight illusion and thus for human heaviness perception. Here we propose a new maximum-likelihood estimation model which describes the illusion as the weighted average of two heaviness estimates with correlated noise: One estimate derived from the object’s mass, and the other from the object’s density, with estimates’ weights based on their relative reliabilities. While information about mass can directly be perceived, information about density will in some cases first have to be derived from mass and volume. However, according to our model at the crucial perceptual level, heaviness judgments will be biased by the objects’ density, not by its size. In two magnitude estimation experiments, we tested model predictions for the visual and the haptic size-weight illusion. Participants lifted objects which varied in mass and density. We additionally varied the reliability of the density estimate by varying the quality of either visual (Experiment 1) or haptic (Experiment 2) volume information. As predicted, with increasing quality of volume information, heaviness judgments were increasingly biased towards the object’s density: Objects of the same density were perceived as more similar and big objects were perceived as increasingly lighter than small (denser) objects of the same mass. This perceived difference increased with an increasing difference in density. In an additional two-alternative forced choice heaviness experiment, we replicated that the illusion strength increased with the quality of volume information (Experiment 3). Overall, the results highly corroborate our model, which seems promising as a starting point for a unifying framework for the size-weight illusion and human heaviness perception. PMID:29447183

A mass-density model can account for the size-weight illusion.

PubMed

Wolf, Christian; Bergmann Tiest, Wouter M; Drewing, Knut

2018-01-01

When judging the heaviness of two objects with equal mass, people perceive the smaller and denser of the two as being heavier. Despite the large number of theories, covering bottom-up and top-down approaches, none of them can fully account for all aspects of this size-weight illusion and thus for human heaviness perception. Here we propose a new maximum-likelihood estimation model which describes the illusion as the weighted average of two heaviness estimates with correlated noise: One estimate derived from the object's mass, and the other from the object's density, with estimates' weights based on their relative reliabilities. While information about mass can directly be perceived, information about density will in some cases first have to be derived from mass and volume. However, according to our model at the crucial perceptual level, heaviness judgments will be biased by the objects' density, not by its size. In two magnitude estimation experiments, we tested model predictions for the visual and the haptic size-weight illusion. Participants lifted objects which varied in mass and density. We additionally varied the reliability of the density estimate by varying the quality of either visual (Experiment 1) or haptic (Experiment 2) volume information. As predicted, with increasing quality of volume information, heaviness judgments were increasingly biased towards the object's density: Objects of the same density were perceived as more similar and big objects were perceived as increasingly lighter than small (denser) objects of the same mass. This perceived difference increased with an increasing difference in density. In an additional two-alternative forced choice heaviness experiment, we replicated that the illusion strength increased with the quality of volume information (Experiment 3). Overall, the results highly corroborate our model, which seems promising as a starting point for a unifying framework for the size-weight illusion and human heaviness perception.

Recent advances in understanding nuclear size and shape

PubMed Central

Mukherjee, Richik N.; Chen, Pan; Levy, Daniel L.

2016-01-01

ABSTRACT Size and shape are important aspects of nuclear structure. While normal cells maintain nuclear size within a defined range, altered nuclear size and shape are associated with a variety of diseases. It is unknown if altered nuclear morphology contributes to pathology, and answering this question requires a better understanding of the mechanisms that control nuclear size and shape. In this review, we discuss recent advances in our understanding of the mechanisms that regulate nuclear morphology, focusing on nucleocytoplasmic transport, nuclear lamins, the endoplasmic reticulum, the cell cycle, and potential links between nuclear size and size regulation of other organelles. We then discuss the functional significance of nuclear morphology in the context of early embryonic development. Looking toward the future, we review new experimental approaches that promise to provide new insights into mechanisms of nuclear size control, in particular microfluidic-based technologies, and discuss how altered nuclear morphology might impact chromatin organization and physiology of diseased cells. PMID:26963026

The effect of a crunchy pseudo-chewing sound on perceived texture of softened foods.

PubMed

Endo, Hiroshi; Ino, Shuichi; Fujisaki, Waka

2016-12-01

Elderly individuals whose ability to chew and swallow has declined are often restricted to unpleasant diets of very soft food, leading to a poor appetite. To address this problem, we aimed to investigate the influence of altered auditory input of chewing sounds on the perception of food texture. The modified chewing sound was reported to influence the perception of food texture in normal foods. We investigated whether the perceived sensations of nursing care foods could be altered by providing altered auditory feedback of chewing sounds, even if the actual food texture is dull. Chewing sounds were generated using electromyogram (EMG) of the masseter. When the frequency properties of the EMG signal are modified and it is heard as a sound, it resembles a "crunchy" sound, much like that emitted by chewing, for example, root vegetables (EMG chewing sound). Thirty healthy adults took part in the experiment. In two conditions (with/without the EMG chewing sound), participants rated the taste, texture and evoked feelings of five kinds of nursing care foods using two questionnaires. When the "crunchy" EMG chewing sound was present, participants were more likely to evaluate food as having the property of stiffness. Moreover, foods were perceived as rougher and to have a greater number of ingredients in the condition with the EMG chewing sound, and satisfaction and pleasantness were also greater. In conclusion, the "crunchy" pseudo-chewing sound could influence the perception of food texture, even if the actual "crunchy" oral sensation is lacking. Considering the effect of altered auditory feedback while chewing, we can suppose that such a tool would be a useful technique to help people on texture-modified diets to enjoy their food. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Perceived Discrimination and Health: A Meta-Analytic Review

PubMed Central

Pascoe, Elizabeth A.; Richman, Laura Smart

2009-01-01

Perceived discrimination has been studied with regard to its impact on several types of health effects. This meta-analysis provides a comprehensive account of the relationships between multiple forms of perceived discrimination and both mental and physical health outcomes. In addition, this meta-analysis examines potential mechanisms by which perceiving discrimination may affect health, including through psychological and physiological stress responses and health behaviors. Analysis of 134 samples suggests that when weighting each study’s contribution by sample size, perceived discrimination has a significant negative effect on both mental and physical health. Perceived discrimination also produces significantly heightened stress responses and is related to participation in unhealthy and nonparticipation in healthy behaviors. These findings suggest potential pathways linking perceived discrimination to negative health outcomes. PMID:19586161

A matter of focus: Power-holders feel more responsible after adopting a cognitive other-focus, rather than a self-focus.

PubMed

Scholl, Annika; Sassenberg, Kai; Scheepers, Daan; Ellemers, Naomi; de Wit, Frank

2017-03-01

Social power implies responsibility. Yet, power-holders often follow only their own interests and overlook this responsibility. The present research illuminates how a previously adopted cognitive focus guides perceived responsibility when a person receives high (vs. low) power. In three experiments, adopting a cognitive focus on another person (vs. on the self or taking over another person's perspective) promoted perceived responsibility among individuals receiving high (but not low) power in a subsequent context. This effect was specific for perceived responsibility - a cognitive focus on another person did not change the perceived opportunity to pursue goals or the perceived relationship to an interaction partner (e.g., interpersonal closeness). While prior research examined how social values (i.e., chronically caring about others) guide responsibility among those holding power, the current findings highlight that mere cognitive processes (i.e., situationally focusing attention on others) alter perceived responsibility among those just about to receive power. © 2016 The British Psychological Society.

Perceived neighborhood ethnic diversity and social outcomes: Context-dependent effects within a postindustrial city undergoing regeneration

PubMed Central

Kearns, Ade; Whitley, Elise

2018-01-01

ABSTRACT This article examines whether perceived neighborhood ethnic diversity is associated with a range of social outcomes in a postindustrial city undergoing regeneration. The research included a survey in 3 types of deprived area in Glasgow: those undergoing regeneration, those directly adjoining regeneration areas, and those further removed from regeneration areas. In areas undergoing regeneration, perceived diversity was positively associated with many residential, cohesion, safety, and empowerment outcomes. This was also true, although to a lesser extent, in deprived areas at some distance from regeneration areas. In areas immediately surrounding the regeneration areas, perceived diversity had mixed associations with residential and safety outcomes and few associations with cohesion and empowerment outcomes. The results suggest that the effects of perceived diversity are context dependent within a city. Moreover, regeneration processes alter neighborhood contexts and therefore enable scale, timing, and duration of diversity to mediate the relationships between perceived diversity and social outcomes. PMID:29479290

Illusions of having small or large invisible bodies influence visual perception of object size

PubMed Central

van der Hoort, Björn; Ehrsson, H. Henrik

2016-01-01

The size of our body influences the perceived size of the world so that objects appear larger to children than to adults. The mechanisms underlying this effect remain unclear. It has been difficult to dissociate visual rescaling of the external environment based on an individual’s visible body from visual rescaling based on a central multisensory body representation. To differentiate these potential causal mechanisms, we manipulated body representation without a visible body by taking advantage of recent developments in body representation research. Participants experienced the illusion of having a small or large invisible body while object-size perception was tested. Our findings show that the perceived size of test-objects was determined by the size of the invisible body (inverse relation), and by the strength of the invisible body illusion. These findings demonstrate how central body representation directly influences visual size perception, without the need for a visible body, by rescaling the spatial representation of the environment. PMID:27708344

Mass is all that matters in the size-weight illusion.

PubMed

Plaisier, Myrthe A; Smeets, Jeroen B J

2012-01-01

An object in outer space is weightless due to the absence of gravity, but astronauts can still judge whether one object is heavier than another one by accelerating the object. How heavy an object feels depends on the exploration mode: an object is perceived as heavier when holding it against the pull of gravity than when accelerating it. At the same time, perceiving an object's size influences the percept: small objects feel heavier than large objects with the same mass (size-weight illusion). Does this effect depend on perception of the pull of gravity? To answer this question, objects were suspended from a long wire and participants were asked to push an object and rate its heaviness. This way the contribution of gravitational forces on the percept was minimised. Our results show that weight is not at all necessary for the illusion because the size-weight illusion occurred without perception of weight. The magnitude of the illusion was independent of whether inertial or gravitational forces were perceived. We conclude that the size-weight illusion does not depend on prior knowledge about weights of object, but instead on a more general knowledge about the mass of objects, independent of the contribution of gravity. Consequently, the size-weight illusion will have the same magnitude on Earth as it should have on the Moon or even under conditions of weightlessness.

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...

Perceived danger while intoxicated uniquely contributes to driving after drinking.

PubMed

Morris, David H; Treloar, Hayley R; Niculete, Maria E; McCarthy, Denis M

2014-02-01

Previous findings suggest that alcohol alters perceptions of risky behaviors such as drinking and driving. However, studies testing these perceptions as a predictor of drinking and driving typically measure these perceptions while participants are sober. This study tested whether the perceived danger of driving after drinking assessed while intoxicated was associated with increased willingness to drive and self-reported drinking-and-driving behavior over and above perceptions assessed while sober. Additionally, we tested the effect of acute tolerance on the perceived danger of driving after drinking assessed on the ascending and descending limbs of the breath alcohol concentration (BrAC) curve. Eighty-two young adults attended 2 counterbalanced laboratory sessions. In one session, participants consumed a moderate dose of alcohol (men: 0.72 g/kg, women: 0.65 g/kg) and reported their perceived danger of driving and willingness to drive at multiple points across the BrAC curve. On a separate occasion, participants remained sober and appraised the dangerousness of driving at a hypothetical, illegal BrAC. Perceptions of the dangerousness of driving following alcohol administration were associated with increased willingness to drive and higher rates of self-reported drinking-and-driving behavior over and above perceptions reported when sober. Furthermore, perceived danger was reduced on the descending limb of the BrAC curve, compared with the ascending limb, suggesting the occurrence of acute tolerance. Results from this study suggest that intoxicated perceptions are uniquely associated with drinking-and-driving decisions and that the perceived danger of drinking and driving is lower on the descending limb of the BrAC curve. Efforts to prevent alcohol-impaired driving have focused on increasing awareness of the danger of driving after drinking. Prevention efforts may be enhanced by educating drivers about how intoxication can alter perceived danger, and interventions may benefit from targeting perceptions of dangerousness while individuals are intoxicated in addition to when they are sober. Copyright © 2013 by the Research Society on Alcoholism.

Perceived Danger while Intoxicated Uniquely Contributes to Driving after Drinking

PubMed Central

Morris, David H.; Treloar, Hayley R.; Niculete, Maria E.; McCarthy, Denis M.

2013-01-01

Background Previous findings suggest that alcohol alters perceptions of risky behaviors such as drinking and driving. However, studies testing these perceptions as a predictor of drinking and driving typically measure these perceptions while participants are sober. The present study tested whether the perceived danger of driving after drinking assessed while intoxicated was associated with increased willingness to drive and self-reported drinking-and-driving behavior over and above perceptions assessed while sober. Additionally, we tested the effect of acute tolerance on the perceived danger of driving after drinking assessed on the ascending and descending limbs of the breath alcohol concentration (BrAC) curve. Methods Eighty-two young adults attended two counterbalanced laboratory sessions. In one session, participants consumed a moderate dose of alcohol (men: .72 g/kg, women: .65 g/kg) and reported the perceived danger of driving and their willingness to drive at multiple points across the BrAC curve. On a separate occasion, participants remained sober and appraised the dangerousness of driving at a hypothetical, illegal BrAC. Results Perceptions of the dangerousness of driving following alcohol administration were associated with increased willingness to drive and higher rates of self-reported drinking-and-driving behavior over and above perceptions reported when sober. Furthermore, perceived danger was reduced on the descending limb of the BrAC curve, compared to the ascending limb, suggesting the occurrence of acute tolerance. Conclusions Results from this study suggest that intoxicated perceptions are uniquely associated with drinking-and-driving decisions and that the perceived danger of drinking and driving is lower on the descending limb of the BrAC curve. Efforts to prevent alcohol-impaired driving have focused on increasing awareness of the danger of driving after drinking. Prevention efforts may be enhanced by educating drivers about how intoxication can alter perceived danger, and interventions may benefit from targeting perceptions of dangerousness while individuals are intoxicated in addition to when they are sober. PMID:24033630

Seeing the body distorts tactile size perception.

PubMed

Longo, Matthew R; Sadibolova, Renata

2013-03-01

Vision of the body modulates somatosensation, even when entirely non-informative about stimulation. For example, seeing the body increases tactile spatial acuity, but reduces acute pain. While previous results demonstrate that vision of the body modulates somatosensory sensitivity, it is unknown whether vision also affects metric properties of touch, and if so how. This study investigated how non-informative vision of the body modulates tactile size perception. We used the mirror box illusion to induce the illusion that participants were directly seeing their stimulated left hand, though they actually saw their reflected right hand. We manipulated whether participants: (a) had the illusion of directly seeing their stimulated left hand, (b) had the illusion of seeing a non-body object at the same location, or (c) looked directly at their non-stimulated right-hand. Participants made verbal estimates of the perceived distance between two tactile stimuli presented simultaneously to the dorsum of the left hand, either 20, 30, or 40mm apart. Vision of the body significantly reduced the perceived size of touch, compared to vision of the object or of the contralateral hand. In contrast, no apparent changes of perceived hand size were found. These results show that seeing the body distorts tactile size perception. Copyright © 2012 Elsevier B.V. All rights reserved.

Nutrition warnings as front-of-pack labels: influence of design features on healthfulness perception and attentional capture.

PubMed

Cabrera, Manuel; Machín, Leandro; Arrúa, Alejandra; Antúnez, Lucía; Curutchet, María Rosa; Giménez, Ana; Ares, Gastón

2017-12-01

Warnings are a new directive front-of-pack (FOP) nutrition labelling scheme that highlights products with high content of key nutrients. The design of warnings influences their ability to catch consumers' attention and to clearly communicate their intended meaning, which are key determinants of their effectiveness. The aim of the present work was to evaluate the influence of design features of warnings as a FOP nutrition labelling scheme on perceived healthfulness and attentional capture. Five studies with a total of 496 people were carried out. In the first study, the association of colour and perceived healthfulness was evaluated in an online survey in which participants had to rate their perceived healthfulness of eight colours. In the second study, the influence of colour, shape and textual information on perceived healthfulness was evaluated using choice-conjoint analysis. The third study focused on implicit associations between two design features (shape and colour) on perceived healthfulness. The fourth and fifth studies used visual search to evaluate the influence of colour, size and position of the warnings on attentional capture. Perceived healthfulness was significantly influenced by shape, colour and textual information. Colour was the variable with the largest contribution to perceived healthfulness. Colour, size and position of the warnings on the labels affected attentional capture. Results from the experiments provide recommendations for the design of warnings to identify products with unfavourable nutrient profile.

A longitudinal study of the relationships between the Big Five personality traits and body size perception.

PubMed

Hartmann, Christina; Siegrist, Michael

2015-06-01

The present study investigated the longitudinal development of body size perception in relation to different personality traits. A sample of Swiss adults (N=2905, 47% men), randomly selected from the telephone book, completed a questionnaire on two consecutive years (2012, 2013). Body size perception was assessed with the Contour Drawing Rating Scale and personality traits were assessed with a short version of the Big Five Inventory. Longitudinal analysis of change indicated that men and women scoring higher on conscientiousness perceived themselves as thinner one year later. In contrast, women scoring higher on neuroticism perceived their body size as larger one year later. No significant effect was observed for men scoring higher on neuroticism. These results were independent of weight changes, body mass index, age, and education. Our findings suggest that personality traits contribute to body size perception among adults. Copyright © 2015 Elsevier Ltd. All rights reserved.

Size Matters: Community Size, HIV Stigma, & Gender Differences

PubMed Central

Gonzalez, Adam; Miller, Carol T.; Solomon, Sondra E.; Bunn, Janice Yanushka; Cassidy, Daniel G.

2012-01-01

Conclusions regarding HIV stigma in rural areas are hampered by lack of agreement about rural classification. This investigation examined perceptions of HIV stigma among males and females with HIV/AIDS in metropolitan, micropolitan, and rural areas. Two-hundred people with HIV/AIDS completed a measure of perceived HIV stigma. Their county or town of residence was used to classify community size. Results indicated that community size was related to one aspect of perceived stigma, disclosure concerns, differently for men and women. Rural women reported more disclosure concerns than did metropolitan and micropolitan women. They also reported more disclosure concerns than rural men. Men in micropolitan communities reported more disclosure concerns than men in rural areas and tended to report more disclosure concerns than men in metropolitan areas. Understanding the relationship of community size to HIV stigmatization requires acknowledging that many communities are neither urban nor rural, and it requires considering gender differences. PMID:18815878

Neural Substrate of Body Size: Illusory Feeling of Shrinking of the Waist

PubMed Central

Kito, Tomonori; Sadato, Norihiro; Passingham, Richard E; Naito, Eiichi

2005-01-01

The perception of the size and shape of one's body (body image) is a fundamental aspect of how we experience ourselves. We studied the neural correlates underlying perceived changes in the relative size of body parts by using a perceptual illusion in which participants felt that their waist was shrinking. We scanned the brains of the participants using functional magnetic resonance imaging. We found that activity in the cortices lining the left postcentral sulcus and the anterior part of the intraparietal sulcus reflected the illusion of waist shrinking, and that this activity was correlated with the reported degree of shrinking. These results suggest that the perceived changes in the size and shape of body parts are mediated by hierarchically higher-order somatosensory areas in the parietal cortex. Based on this finding we suggest that relative size of body parts is computed by the integration of more elementary somatic signals from different body segments. PMID:16336049

Blade size and weight effects in shovel design.

PubMed

Freivalds, A; Kim, Y J

1990-03-01

The shovel is a basic tool that has undergone only nominal systematic design changes. Although previous studies found shovel-weight and blade-size effects of shovelling, the exact trade-off between the two has not been quantified. Energy expenditure, heart rate, ratings of perceived exertion and shovelling performance were measured on five subjects using five shovels with varying blade sizes and weights to move sand. Energy expenditure, normalised to subject weight and load handled, varied quadratically with the blade-size/shovel-weight (B/W) ratio. Minimum energy cost was at B/W = 0.0676 m2/kg, which for an average subject and average load would require an acceptable 5.16 kcal/min of energy expenditure. Subjects, through the ratings of perceived exertion, also strongly preferred the lighter shovels without regard to blade size. Too large a blade or too heavy a shovel increased energy expenditure beyond acceptable levels, while too small a blade reduced efficiency of the shovelling.

Multimodal lightsheet, structured illumination and Airyscan superresolution microscopy of chloroplast size and its impact on light propagation

USDA-ARS?s Scientific Manuscript database

Altering chloroplast size changes the way light propagates through a leaf by altering light reflectance and transmission as well as absorption by chlorophyll. Thus changing chloroplast size can used to manipulate leaf optical properties to optimize photosynthetic efficiency with the ultimate goal of...

An examination of the perceptions of social network characteristics associated with grandiose and vulnerable narcissism.

PubMed

Lamkin, Joanna; Clifton, Allan; Campbell, W Keith; Miller, Joshua D

2014-04-01

Two dimensions of narcissism exist, grandiose and vulnerable, which are thought to be associated with distinctly different patterns of interpersonal behavior. Social network analysis is a way of quantifying and analyzing interpersonal interactions that may prove useful for characterizing the networks associated with these narcissism dimensions. In the current study, participants (N = 148) completed scales assessing both narcissism dimensions and a measure of the five-factor model of personality. Egocentric network information about participants' 30 closest friends and family members (i.e., "alters") was also obtained. Both narcissism dimensions were characterized by negative perceptions of the individuals who comprise one's social networks, and many of these relations were mediated by individuals' higher levels of antagonism. Grandiose narcissism also interacted with alter centrality (i.e., importance to the network) such that individuals low on grandiose narcissism were less likely to perceive central alters in a negative light and were more attuned to central alters than were individuals high on grandiose narcissism. Overall, both narcissism dimensions were associated with perceiving one's overall social environment negatively because of the high levels of antagonism that characterize both narcissism dimensions. Individuals high on grandiose narcissism, however, appear to be more insensitive to the relative importance of individuals in their social networks. PsycINFO Database Record (c) 2014 APA, all rights reserved

The effects of alterations in the osseous external auditory canal on perceived sound quality.

PubMed

van Spronsen, Erik; Brienesse, Patrick; Ebbens, Fenna A; Waterval, Jerome J; Dreschler, Wouter A

2015-10-01

To evaluate the perceptual effect of the altered shape of the osseous external auditory canal (OEAC) on sound quality. Prospective study. Twenty subjects with normal hearing were presented with six simulated sound conditions representing the acoustic properties of six different ear canals (three normal ears and three cavities). The six different real ear unaided responses of these ear canals were used to filter Dutch sentences, resulting in six simulated sound conditions. A seventh unfiltered reference condition was used for comparison. Sound quality was evaluated using paired comparison ratings and a visual analog scale (VAS). Significant differences in sound quality were found between the normal and cavity conditions (all P < .001) using both the seven-point paired comparison rating and the VAS. No significant differences were found between the reference and normal conditions. Sound quality deteriorates when the OEAC is altered into a cavity. This proof of concept study shows that the altered acoustic quality of the OEAC after radical cavity surgery may lead to a clearly perceived deterioration in sound quality. Nevertheless, some questions remain about the extent to which these changes are affected by habituation and by other changes in middle ear anatomy and functionality. 4 © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Sensory, Cognitive, and Sensorimotor Learning Effects in Recognition Memory for Music.

PubMed

Mathias, Brian; Tillmann, Barbara; Palmer, Caroline

2016-08-01

Recent research suggests that perception and action are strongly interrelated and that motor experience may aid memory recognition. We investigated the role of motor experience in auditory memory recognition processes by musicians using behavioral, ERP, and neural source current density measures. Skilled pianists learned one set of novel melodies by producing them and another set by perception only. Pianists then completed an auditory memory recognition test during which the previously learned melodies were presented with or without an out-of-key pitch alteration while the EEG was recorded. Pianists indicated whether each melody was altered from or identical to one of the original melodies. Altered pitches elicited a larger N2 ERP component than original pitches, and pitches within previously produced melodies elicited a larger N2 than pitches in previously perceived melodies. Cortical motor planning regions were more strongly activated within the time frame of the N2 following altered pitches in previously produced melodies compared with previously perceived melodies, and larger N2 amplitudes were associated with greater detection accuracy following production learning than perception learning. Early sensory (N1) and later cognitive (P3a) components elicited by pitch alterations correlated with predictions of sensory echoic and schematic tonality models, respectively, but only for the perception learning condition, suggesting that production experience alters the extent to which performers rely on sensory and tonal recognition cues. These findings provide evidence for distinct time courses of sensory, schematic, and motoric influences within the same recognition task and suggest that learned auditory-motor associations influence responses to out-of-key pitches.

The consequences of perceived discrimination for psychological well-being: a meta-analytic review.

PubMed

Schmitt, Michael T; Branscombe, Nyla R; Postmes, Tom; Garcia, Amber

2014-07-01

In 2 meta-analyses, we examined the relationship between perceived discrimination and psychological well-being and tested a number of moderators of that relationship. In Meta-Analysis 1 (328 independent effect sizes, N = 144,246), we examined correlational data measuring both perceived discrimination and psychological well-being (e.g., self-esteem, depression, anxiety, psychological distress, life satisfaction). Using a random-effects model, the mean weighted effect size was significantly negative, indicating harm (r = -.23). Effect sizes were larger for disadvantaged groups (r = -.24) compared to advantaged groups (r = -.10), larger for children compared to adults, larger for perceptions of personal discrimination compared to group discrimination, and weaker for racism and sexism compared to other stigmas. The negative relationship was significant across different operationalizations of well-being but was somewhat weaker for positive outcomes (e.g., self-esteem, positive affect) than for negative outcomes (e.g., depression, anxiety, negative affect). Importantly, the effect size was significantly negative even in longitudinal studies that controlled for prior levels of well-being (r = -.15). In Meta-Analysis 2 (54 independent effect sizes, N = 2,640), we examined experimental data from studies manipulating perceptions of discrimination and measuring well-being. We found that the effect of discrimination on well-being was significantly negative for studies that manipulated general perceptions of discrimination (d = -.25), but effects did not differ from 0 when attributions to discrimination for a specific negative event were compared to personal attributions (d = .06). Overall, results support the idea that the pervasiveness of perceived discrimination is fundamental to its harmful effects on psychological well-being. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Body size perceptions among Pakistani women in Norway participating in a controlled trial to prevent deterioration of glucose tolerance.

PubMed

Hussain, Aysha; Bjørge, Benedikte; Hjellset, Victoria T; Holmboe-Ottesen, Gerd; Wandel, Margareta

2010-06-01

South Asians are prone to diabetes type 2 and cardiovascular diseases, which can be prevented by a diet leading to weight reduction. Body size perceptions may influence compliance to dietary advice. The objective was to study body size perceptions among Pakistani immigrant women in Norway, enrolled in a controlled trial to prevent deterioration of glucose tolerance by focussing on diet and physical activity. Participants (n=198) were 25-62 years of age, 79.8% had BMI > 25 and mean BMI was 29.6. Data were collected by questionnaire interviews with Punjabi/Urdu speaking interviewers, and body weight and height were measured. This article is based on baseline data. Stunkard's Figure Rating Scale was used. The scale consists of nine figures, representing women with different body shapes, from very thin (1-2) to very obese (6-9). The women were asked which body size they thought would connote health and wealth. A significantly smaller body size was related to health (mean 2.9) than to wealth (mean 3.3), p<0.01, and both were smaller than their self-rated own body size (mean 5.7), p<0.01. The women perceived that Pakistanis in Norway prefer women to have a smaller body size (mean 3.4) than people in Pakistan (mean 4.5), but larger than Norwegians (mean 2.5). A discrepancy score was calculated between self-rated own body size and perceived body size preference among Pakistanis in Norway. BMI was positively associated, and level of education negatively associated, with the discrepancy score. The women related body size numbers to BMI similarly to what has been described for US women. In conclusion, body size preferences among Pakistani women in this study were within the range of normal weight. However, there was a large discrepancy between own self-rated body size and the perceived ideal for Pakistanis in Norway.

Perceived sources of change in trainees' self-efficacy beliefs.

PubMed

Lent, Robert W; Cinamon, Rachel Gali; Bryan, Nicole A; Jezzi, Matthew M; Martin, Helena M; Lim, Robert

2009-09-01

Thought-listing procedures were used to examine the perceived incidence, size, direction, and bases of change in the session-level self-efficacy of therapists in training. Ninety-eight Master's-level trainees completed a cognitive assessment task immediately after each session with a client in their first practicum. Participants typically reported modest-sized, positive changes in their therapeutic self-efficacy at each session. Seven perceived sources of change in self-efficacy were identified. Some of these sources (e.g., trainees' performance evaluations, affective reactions) were consistent with general self-efficacy theory; others reflected the interpersonal performance context of therapy (e.g., perceptions of the therapeutic relationship and client behavior). Implications of the findings for training and future research on therapist development are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Length of home hospice care, family-perceived timing of referrals, perceived quality of care, and quality of death and dying in terminally ill cancer patients who died at home.

PubMed

Yamagishi, Akemi; Morita, Tatsuya; Kawagoe, Shohei; Shimizu, Megumi; Ozawa, Taketoshi; An, Emi; Kobayakawa, Makoto; Tsuneto, Satoru; Shima, Yasuo; Miyashita, Mitsunori

2015-02-01

This study aims to clarify the length of home hospice care, family-perceived timing of referrals, and their effects on the family-perceived quality of care and quality of death and dying of terminally ill cancer patients who died at home and identify the determinants of perceived late referrals. A multicenter questionnaire survey was conducted involving 1,052 family members of cancer patients who died at home supported by 15 home-based hospice services throughout Japan. A total of 693 responses were analyzed (effective response rate, 66 %). Patients received home-based hospice care for a median of 35.0 days, and 8.0 % received home hospice care for less than 1 week. While 1.5 % of the families reported the timing of referrals as early, 42 % reported the timing as late or too late. The families of patients with a length of care of less than 4 weeks were more likely to regard the timing of referrals as late or too late. The patients of family members who regarded the timing of referrals as late or too late had a significantly lower perceived quality of care (effect size, 0.18; P = 0.039) and lower quality of death and dying (effect size, 0.15, P = 0.063). Independent determinants of higher likelihoods of perceived late referrals included: frequent visits to emergency departments, patient being unprepared for worsening condition, and patient having concerns about relationship with new doctor. Discharge nurse availability was independently associated with lower likelihoods of perceived late referrals. A significant number of bereaved families regarded the timing of referrals to home hospices as late, and the perceived timing was associated with the family-perceived quality of care and quality of death and dying. Systematic strategies to overcome the barriers related to perceived late referrals are necessary.

Itsy bitsy spider?: Valence and self-relevance predict size estimation.

PubMed

Leibovich, Tali; Cohen, Noga; Henik, Avishai

2016-12-01

The current study explored the role of valence and self-relevance in size estimation of neutral and aversive animals. In Experiment 1, participants who were highly fearful of spiders and participants with low fear of spiders rated the size and unpleasantness of spiders and other neutral animals (birds and butterflies). We found that although individuals with both high and low fear of spiders rated spiders as highly unpleasant, only the highly fearful participants rated spiders as larger than butterflies. Experiment 2 included additional pictures of wasps (not self-relevant, but unpleasant) and beetles. The results of this experiment replicated those of Experiment 1 and showed a similar bias in size estimation for beetles, but not for wasps. Mediation analysis revealed that in the high-fear group both relevance and valence influenced perceived size, whereas in the low-fear group only valence affected perceived size. These findings suggest that the effect of highly relevant stimuli on size perception is both direct and mediated by valence. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Sound iconicity of abstract concepts: Place of articulation is implicitly associated with abstract concepts of size and social dominance.

PubMed

Auracher, Jan

2017-01-01

The concept of sound iconicity implies that phonemes are intrinsically associated with non-acoustic phenomena, such as emotional expression, object size or shape, or other perceptual features. In this respect, sound iconicity is related to other forms of cross-modal associations in which stimuli from different sensory modalities are associated with each other due to the implicitly perceived correspondence of their primal features. One prominent example is the association between vowels, categorized according to their place of articulation, and size, with back vowels being associated with bigness and front vowels with smallness. However, to date the relative influence of perceptual and conceptual cognitive processing on this association is not clear. To bridge this gap, three experiments were conducted in which associations between nonsense words and pictures of animals or emotional body postures were tested. In these experiments participants had to infer the relation between visual stimuli and the notion of size from the content of the pictures, while directly perceivable features did not support-or even contradicted-the predicted association. Results show that implicit associations between articulatory-acoustic characteristics of phonemes and pictures are mainly influenced by semantic features, i.e., the content of a picture, whereas the influence of perceivable features, i.e., size or shape, is overridden. This suggests that abstract semantic concepts can function as an interface between different sensory modalities, facilitating cross-modal associations.

Differential investments and opportunities: How do neighborhood conditions moderate the relationship between perceived housing discrimination and social capital?

PubMed

Yang, Tse-Chuan; Chen, I-Chien; Kim, Seulki; Choi, Seung-Won

2018-05-01

Though the adverse consequences of perceived housing discrimination have been documented, little is known about whether such experience undermines one's social capital in a neighborhood and even less is about whether and how this relationship is altered by neighborhood features. We proposed a framework that simultaneously considers within-individual and between-neighborhood processes. We applied multilevel structural equation models to data from Philadelphia (n = 9987) and found that (a) perceived housing discrimination was negatively associated with one's social capital even after other confounders were considered, (b) this negative association could be partly explained by the proliferated daily stress and anxiety mechanisms, (c) differential exposures to neighborhood social disadvantage accounted for the variation in social capital across neighborhoods, and (d) the adverse association between perceived housing discrimination and social capital could be attenuated by neighborhood stability. The findings suggested that appropriate interventions should buffer the negative association of perceived housing discrimination with social capital. Copyright © 2018 Elsevier Inc. All rights reserved.

Facial cues to perceived height influence leadership choices in simulated war and peace contexts.

PubMed

Re, Daniel E; DeBruine, Lisa M; Jones, Benedict C; Perrett, David I

2013-01-31

Body size and other signs of physical prowess are associated with leadership hierarchies in many social species. Here we (1) assess whether facial cues associated with perceived height and masculinity have different effects on leadership judgments in simulated wartime and peacetime contexts and (2) test how facial cues associated with perceived height and masculinity influence dominance perceptions. Results indicate that cues associated with perceived height and masculinity in potential leaders‟ faces are valued more in a wartime (vs. peacetime) context. Furthermore, increasing cues of apparent height and masculinity in faces increased perceived dominance. Together, these findings suggest that facial cues of physical stature contribute to establishing leadership hierarchies in humans.

Measuring the amplification of attention

PubMed Central

Blaser, Erik; Sperling, George; Lu, Zhong-Lin

1999-01-01

An ambiguous motion paradigm, in which the direction of apparent motion is determined by salience (i.e., the extent to which an area is perceived as figure versus ground), is used to assay the amplification of color by attention to color. In the red–green colored gratings used in these experiments, without attention instructions, salience depends on the chromaticity difference between colored stripes embedded in the motion sequence and the yellow background. Selective attention to red (or to green) alters the perceived direction of motion and is found to be equivalent to increasing the physical redness (or greenness) by 25–117%, depending on the observer and color. Whereas attention to a color drastically alters the salience of that color, it leaves color appearance unchanged. A computational model, which embodies separate, parallel pathways for object perception and for salience, accounts for 99% of the variance of the experimental data. PMID:10500237

Measuring the amplification of attention.

PubMed

Blaser, E; Sperling, G; Lu, Z L

1999-09-28

An ambiguous motion paradigm, in which the direction of apparent motion is determined by salience (i.e., the extent to which an area is perceived as figure versus ground), is used to assay the amplification of color by attention to color. In the red-green colored gratings used in these experiments, without attention instructions, salience depends on the chromaticity difference between colored stripes embedded in the motion sequence and the yellow background. Selective attention to red (or to green) alters the perceived direction of motion and is found to be equivalent to increasing the physical redness (or greenness) by 25-117%, depending on the observer and color. Whereas attention to a color drastically alters the salience of that color, it leaves color appearance unchanged. A computational model, which embodies separate, parallel pathways for object perception and for salience, accounts for 99% of the variance of the experimental data.

Acceptability and potential effectiveness of commercial portion control tools amongst people with obesity.

PubMed

Almiron-Roig, Eva; Domínguez, Angélica; Vaughan, David; Solis-Trapala, Ivonne; Jebb, Susan A

2016-12-01

Exposure to large portion sizes is a risk factor for obesity. Specifically designed tableware may modulate how much is eaten and help with portion control. We examined the experience of using a guided crockery set (CS) and a calibrated serving spoon set (SS) by individuals trying to manage their weight. Twenty-nine obese adults who had completed 7-12 weeks of a community weight-loss programme were invited to use both tools for 2 weeks each, in a crossover design, with minimal health professional contact. A paper-based questionnaire was used to collect data on acceptance, perceived changes in portion size, frequency, and type of meal when the tool was used. Scores describing acceptance, ease of use and perceived effectiveness were derived from five-point Likert scales from which binary indicators (high/low) were analysed using logistic regression. Mean acceptance, ease of use and perceived effectiveness were moderate to high (3·7-4·4 points). Tool type did not have an impact on indicators of acceptance, ease of use and perceived effectiveness (P>0·32 for all comparisons); 55 % of participants used the CS on most days v. 21 % for the SS. The CS was used for all meals, whereas the SS was mostly used for evening meals. Self-selected portion sizes increased for vegetables and decreased for chips and potatoes with both tools. Participants rated both tools as equally acceptable, easy to use and with similar perceived effectiveness. Formal trials to evaluate the impact of such tools on weight control are warranted.

Body image, body dissatisfaction and weight status in South Asian children: a cross-sectional study.

PubMed

Pallan, Miranda J; Hiam, Lucinda C; Duda, Joan L; Adab, Peymane

2011-01-09

Childhood obesity is a continuing problem in the UK and South Asian children represent a group that are particularly vulnerable to its health consequences. The relationship between body dissatisfaction and obesity is well documented in older children and adults, but is less clear in young children, particularly South Asians. A better understanding of this relationship in young South Asian children will inform the design and delivery of obesity intervention programmes. The aim of this study is to describe body image size perception and dissatisfaction, and their relationship to weight status in primary school aged UK South Asian children. Objective measures of height and weight were undertaken on 574 predominantly South Asian children aged 5-7 (296 boys and 278 girls). BMI z-scores, and weight status (underweight, healthy weight, overweight or obese) were calculated based on the UK 1990 BMI reference charts. Figure rating scales were used to assess perceived body image size (asking children to identify their perceived body size) and dissatisfaction (difference between perceived current and ideal body size). The relationship between these and weight status were examined using multivariate analyses. Perceived body image size was positively associated with weight status (partial regression coefficient for overweight/obese vs. non-overweight/obese was 0.63 (95% CI 0.26-0.99) and for BMI z-score was 0.21 (95% CI 0.10-0.31), adjusted for sex, age and ethnicity). Body dissatisfaction was also associated with weight status, with overweight and obese children more likely to select thinner ideal body size than healthy weight children (adjusted partial regression coefficient for overweight/obese vs. non-overweight/obese was 1.47 (95% CI 0.99-1.96) and for BMI z-score was 0.54 (95% CI 0.40-0.67)). Awareness of body image size and increasing body dissatisfaction with higher weight status is established at a young age in this population. This needs to be considered when designing interventions to reduce obesity in young children, in terms of both benefits and harms.

Body image, body dissatisfaction and weight status in south asian children: a cross-sectional study

PubMed Central

2011-01-01

Background Childhood obesity is a continuing problem in the UK and South Asian children represent a group that are particularly vulnerable to its health consequences. The relationship between body dissatisfaction and obesity is well documented in older children and adults, but is less clear in young children, particularly South Asians. A better understanding of this relationship in young South Asian children will inform the design and delivery of obesity intervention programmes. The aim of this study is to describe body image size perception and dissatisfaction, and their relationship to weight status in primary school aged UK South Asian children. Methods Objective measures of height and weight were undertaken on 574 predominantly South Asian children aged 5-7 (296 boys and 278 girls). BMI z-scores, and weight status (underweight, healthy weight, overweight or obese) were calculated based on the UK 1990 BMI reference charts. Figure rating scales were used to assess perceived body image size (asking children to identify their perceived body size) and dissatisfaction (difference between perceived current and ideal body size). The relationship between these and weight status were examined using multivariate analyses. Results Perceived body image size was positively associated with weight status (partial regression coefficient for overweight/obese vs. non-overweight/obese was 0.63 (95% CI 0.26-0.99) and for BMI z-score was 0.21 (95% CI 0.10-0.31), adjusted for sex, age and ethnicity). Body dissatisfaction was also associated with weight status, with overweight and obese children more likely to select thinner ideal body size than healthy weight children (adjusted partial regression coefficient for overweight/obese vs. non-overweight/obese was 1.47 (95% CI 0.99-1.96) and for BMI z-score was 0.54 (95% CI 0.40-0.67)). Conclusions Awareness of body image size and increasing body dissatisfaction with higher weight status is established at a young age in this population. This needs to be considered when designing interventions to reduce obesity in young children, in terms of both benefits and harms. PMID:21214956

Predicting Ideological Prejudice

PubMed Central

Brandt, Mark J.

2017-01-01

A major shortcoming of current models of ideological prejudice is that although they can anticipate the direction of the association between participants’ ideology and their prejudice against a range of target groups, they cannot predict the size of this association. I developed and tested models that can make specific size predictions for this association. A quantitative model that used the perceived ideology of the target group as the primary predictor of the ideology-prejudice relationship was developed with a representative sample of Americans (N = 4,940) and tested against models using the perceived status of and choice to belong to the target group as predictors. In four studies (total N = 2,093), ideology-prejudice associations were estimated, and these observed estimates were compared with the models’ predictions. The model that was based only on perceived ideology was the most parsimonious with the smallest errors. PMID:28394693

Using visuo-kinetic virtual reality to induce illusory spinal movement: the MoOVi Illusion

PubMed Central

Smith, Ross T.; Hunter, Estin V.; Davis, Miles G.; Sterling, Michele; Moseley, G. Lorimer

2017-01-01

Background Illusions that alter perception of the body provide novel opportunities to target brain-based contributions to problems such as persistent pain. One example of this, mirror therapy, uses vision to augment perceived movement of a painful limb to treat pain. Since mirrors can’t be used to induce augmented neck or other spinal movement, we aimed to test whether such an illusion could be achieved using virtual reality, in advance of testing its potential therapeutic benefit. We hypothesised that perceived head rotation would depend on visually suggested movement. Method In a within-subjects repeated measures experiment, 24 healthy volunteers performed neck movements to 50o of rotation, while a virtual reality system delivered corresponding visual feedback that was offset by a factor of 50%–200%—the Motor Offset Visual Illusion (MoOVi)—thus simulating more or less movement than that actually occurring. At 50o of real-world head rotation, participants pointed in the direction that they perceived they were facing. The discrepancy between actual and perceived direction was measured and compared between conditions. The impact of including multisensory (auditory and visual) feedback, the presence of a virtual body reference, and the use of 360o immersive virtual reality with and without three-dimensional properties, was also investigated. Results Perception of head movement was dependent on visual-kinaesthetic feedback (p = 0.001, partial eta squared = 0.17). That is, altered visual feedback caused a kinaesthetic drift in the direction of the visually suggested movement. The magnitude of the drift was not moderated by secondary variables such as the addition of illusory auditory feedback, the presence of a virtual body reference, or three-dimensionality of the scene. Discussion Virtual reality can be used to augment perceived movement and body position, such that one can perform a small movement, yet perceive a large one. The MoOVi technique tested here has clear potential for assessment and therapy of people with spinal pain. PMID:28243537

Using visuo-kinetic virtual reality to induce illusory spinal movement: the MoOVi Illusion.

PubMed

Harvie, Daniel S; Smith, Ross T; Hunter, Estin V; Davis, Miles G; Sterling, Michele; Moseley, G Lorimer

2017-01-01

Illusions that alter perception of the body provide novel opportunities to target brain-based contributions to problems such as persistent pain. One example of this, mirror therapy, uses vision to augment perceived movement of a painful limb to treat pain. Since mirrors can't be used to induce augmented neck or other spinal movement, we aimed to test whether such an illusion could be achieved using virtual reality, in advance of testing its potential therapeutic benefit. We hypothesised that perceived head rotation would depend on visually suggested movement. In a within-subjects repeated measures experiment, 24 healthy volunteers performed neck movements to 50 o of rotation, while a virtual reality system delivered corresponding visual feedback that was offset by a factor of 50%-200%-the Motor Offset Visual Illusion (MoOVi)-thus simulating more or less movement than that actually occurring. At 50 o of real-world head rotation, participants pointed in the direction that they perceived they were facing. The discrepancy between actual and perceived direction was measured and compared between conditions. The impact of including multisensory (auditory and visual) feedback, the presence of a virtual body reference, and the use of 360 o immersive virtual reality with and without three-dimensional properties, was also investigated. Perception of head movement was dependent on visual-kinaesthetic feedback ( p  = 0.001, partial eta squared = 0.17). That is, altered visual feedback caused a kinaesthetic drift in the direction of the visually suggested movement. The magnitude of the drift was not moderated by secondary variables such as the addition of illusory auditory feedback, the presence of a virtual body reference, or three-dimensionality of the scene. Virtual reality can be used to augment perceived movement and body position, such that one can perform a small movement, yet perceive a large one. The MoOVi technique tested here has clear potential for assessment and therapy of people with spinal pain.

Size Constancy in Bat Biosonar? Perceptual Interaction of Object Aperture and Distance

PubMed Central

Heinrich, Melina; Wiegrebe, Lutz

2013-01-01

Perception and encoding of object size is an important feature of sensory systems. In the visual system object size is encoded by the visual angle (visual aperture) on the retina, but the aperture depends on the distance of the object. As object distance is not unambiguously encoded in the visual system, higher computational mechanisms are needed. This phenomenon is termed “size constancy”. It is assumed to reflect an automatic re-scaling of visual aperture with perceived object distance. Recently, it was found that in echolocating bats, the ‘sonar aperture’, i.e., the range of angles from which sound is reflected from an object back to the bat, is unambiguously perceived and neurally encoded. Moreover, it is well known that object distance is accurately perceived and explicitly encoded in bat sonar. Here, we addressed size constancy in bat biosonar, recruiting virtual-object techniques. Bats of the species Phyllostomus discolor learned to discriminate two simple virtual objects that only differed in sonar aperture. Upon successful discrimination, test trials were randomly interspersed using virtual objects that differed in both aperture and distance. It was tested whether the bats spontaneously assigned absolute width information to these objects by combining distance and aperture. The results showed that while the isolated perceptual cues encoding object width, aperture, and distance were all perceptually well resolved by the bats, the animals did not assign absolute width information to the test objects. This lack of sonar size constancy may result from the bats relying on different modalities to extract size information at different distances. Alternatively, it is conceivable that familiarity with a behaviorally relevant, conspicuous object is required for sonar size constancy, as it has been argued for visual size constancy. Based on the current data, it appears that size constancy is not necessarily an essential feature of sonar perception in bats. PMID:23630598

Size constancy in bat biosonar? Perceptual interaction of object aperture and distance.

PubMed

Heinrich, Melina; Wiegrebe, Lutz

2013-01-01

Perception and encoding of object size is an important feature of sensory systems. In the visual system object size is encoded by the visual angle (visual aperture) on the retina, but the aperture depends on the distance of the object. As object distance is not unambiguously encoded in the visual system, higher computational mechanisms are needed. This phenomenon is termed "size constancy". It is assumed to reflect an automatic re-scaling of visual aperture with perceived object distance. Recently, it was found that in echolocating bats, the 'sonar aperture', i.e., the range of angles from which sound is reflected from an object back to the bat, is unambiguously perceived and neurally encoded. Moreover, it is well known that object distance is accurately perceived and explicitly encoded in bat sonar. Here, we addressed size constancy in bat biosonar, recruiting virtual-object techniques. Bats of the species Phyllostomus discolor learned to discriminate two simple virtual objects that only differed in sonar aperture. Upon successful discrimination, test trials were randomly interspersed using virtual objects that differed in both aperture and distance. It was tested whether the bats spontaneously assigned absolute width information to these objects by combining distance and aperture. The results showed that while the isolated perceptual cues encoding object width, aperture, and distance were all perceptually well resolved by the bats, the animals did not assign absolute width information to the test objects. This lack of sonar size constancy may result from the bats relying on different modalities to extract size information at different distances. Alternatively, it is conceivable that familiarity with a behaviorally relevant, conspicuous object is required for sonar size constancy, as it has been argued for visual size constancy. Based on the current data, it appears that size constancy is not necessarily an essential feature of sonar perception in bats.

Depth reversals in stereoscopic displays driven by apparent size

NASA Astrophysics Data System (ADS)

Sacher, Gunnar; Hayes, Amy; Thornton, Ian M.; Sereno, Margaret E.; Malony, Allen D.

1998-04-01

In visual scenes, depth information is derived from a variety of monocular and binocular cues. When in conflict, a monocular cue is sometimes able to override the binocular information. We examined the accuracy of relative depth judgments in orthographic, stereoscopic displays and found that perceived relative size can override binocular disparity as a depth cue in a situation where the relative size information is itself generated from disparity information, not from retinal size difference. A size discrimination task confirmed the assumption that disparity information was perceived and used to generate apparent size differences. The tendency for the apparent size cue to override disparity information can be modulated by varying the strength of the apparent size cue. In addition, an analysis of reaction times provides supporting evidence for this novel depth reversal effect. We believe that human perception must be regarded as an important component of stereoscopic applications. Hence, if applications are to be effective and accurate, it is necessary to take into account the richness and complexity of the human visual perceptual system that interacts with them. We discuss implications of this and similar research for human performance in virtual environments, the design of visual presentations for virtual worlds, and the design of visualization tools.

Hispanic maternal influences on daughters' unhealthy weight control behaviors: The role of maternal acculturation, adiposity, and body image disturbances.

PubMed

Olvera, Norma; Matthews-Ewald, Molly R; McCarley, Kendall; Scherer, Rhonda; Posada, Alexandria

2016-12-01

This study examined whether maternal adiposity, acculturation, and perceived-ideal body size discrepancy for daughters were associated with daughters' engagement in unhealthy weight control behaviors. A total of 97 Hispanic mother-daughter dyads completed surveys, rated a figure scale, and had their height, weight, and adiposity assessed. Mothers (M age =39.00, SD=6.20 years) selected larger ideal body sizes for their daughters (M age =11.12, SD=1.53 years) than their daughters selected for themselves. Mothers had a smaller difference between their perception of their daughters' body size and ideal body size compared to the difference between their daughters' selection of their perceived and ideal body size. More acculturated mothers and those mothers with larger waist-to-hip ratios were more likely to have daughters who engaged in unhealthy weight control behaviors. These findings highlight the relevant role that maternal acculturation and adiposity may have in influencing daughters' unhealthy weight control behaviors. Published by Elsevier Ltd.

The perceptual homunculus: the perception of the relative proportions of the human body.

PubMed

Linkenauger, Sally A; Wong, Hong Yu; Geuss, Michael; Stefanucci, Jeanine K; McCulloch, Kathleen C; Bülthoff, Heinrich H; Mohler, Betty J; Proffitt, Dennis R

2015-02-01

Given that observing one's body is ubiquitous in experience, it is natural to assume that people accurately perceive the relative sizes of their body parts. This assumption is mistaken. In a series of studies, we show that there are dramatic systematic distortions in the perception of bodily proportions, as assessed by visual estimation tasks, where participants were asked to compare the lengths of two body parts. These distortions are not evident when participants estimate the extent of a body part relative to a noncorporeal object or when asked to estimate noncorporal objects that are the same length as their body parts. Our results reveal a radical asymmetry in the perception of corporeal and noncorporeal relative size estimates. Our findings also suggest that people visually perceive the relative size of their body parts as a function of each part's relative tactile sensitivity and physical size.

Turbidity in oil-in-water-emulsions - Key factors and visual perception.

PubMed

Linke, C; Drusch, S

2016-11-01

The aim of the present study is to systematically describe the factors affecting turbidity in beverage emulsions and to get a better understanding of visual perception of turbidity. The sensory evaluation of the human visual perception of turbidity showed that humans are most sensitive to turbidity differences between two samples in the range between 1000 and 1500 NTU (ratio) (nephelometric turbidity units). At very high turbidity values >2000 TU in NTU (ratio) were needed to distinguish between samples that they were perceived significantly different. Particle size was the most important factor affecting turbidity. It was shown that a maximum turbidity occurs at a mean volume - surface diameter of 0.2μm for the oil droplet size. Additional parameters were the refractive index, the composition of the aqueous phase and the presence of excess emulsifier. In a concentration typical for a beverage emulsion a change in the refractive index of the oil phase may allow the alteration of turbidity by up to 30%. With the knowledge on visual perception of turbidity and the determining factors, turbidity can be tailored in product development according to the customer requirements and in quality control to define acceptable variations in optical appearance. Copyright © 2016. Published by Elsevier Ltd.

Iraqi adolescents: self-regard, self-derogation, and perceived threat in war.

PubMed

Carlton-Ford, Steve; Ender, Morten G; Tabatabai, Ahoo

2008-02-01

A year into the 2003 US-Iraq war, how were adolescents in Baghdad faring? Conflict-related events typically lower psychological well-being; in contrast, investment in and protection of threatened identities should lead to self-esteem striving and, presumably, better well-being. How threatened do Iraqi adolescents feel? Is their self-esteem related to their sense of threat? Do age, religion, ethnicity, and gender alter the link between perceived threat and self-esteem? We use data from 1000 randomly selected adolescents living in Baghdad during July 2004. Iraqi adolescents reported high levels of threat; those feeling more threatened reported higher levels of self-esteem. Social background correlates with both self-esteem and perceived threat, but controlling for social background does not eliminate the relationship between self-esteem and perceived threat. We interpret our results in light of theory and research concerning social identity, mortality threats, and war trauma.

Myeloid differentiation architecture of leukocyte transcriptome dynamics in perceived social isolation

PubMed Central

Cole, Steven W.; Capitanio, John P.; Chun, Katie; Arevalo, Jesusa M. G.; Ma, Jeffrey; Cacioppo, John T.

2015-01-01

To define the cellular mechanisms of up-regulated inflammatory gene expression and down-regulated antiviral response in people experiencing perceived social isolation (loneliness), we conducted integrative analyses of leukocyte gene regulation in humans and rhesus macaques. Five longitudinal leukocyte transcriptome surveys in 141 older adults showed up-regulation of the sympathetic nervous system (SNS), monocyte population expansion, and up-regulation of the leukocyte conserved transcriptional response to adversity (CTRA). Mechanistic analyses in a macaque model of perceived social isolation confirmed CTRA activation and identified selective up-regulation of the CD14++/CD16− classical monocyte transcriptome, functional glucocorticoid desensitization, down-regulation of Type I and II interferons, and impaired response to infection by simian immunodeficiency virus (SIV). These analyses identify neuroendocrine-related alterations in myeloid cell population dynamics as a key mediator of CTRA transcriptome skewing, which may both propagate perceived social isolation and contribute to its associated health risks. PMID:26598672

Emotion and anxiety potentiate the way attention alters visual appearance.

PubMed

Barbot, Antoine; Carrasco, Marisa

2018-04-12

The ability to swiftly detect and prioritize the processing of relevant information around us is critical for the way we interact with our environment. Selective attention is a key mechanism that serves this purpose, improving performance in numerous visual tasks. Reflexively attending to sudden information helps detect impeding threat or danger, a possible reason why emotion modulates the way selective attention affects perception. For instance, the sudden appearance of a fearful face potentiates the effects of exogenous (involuntary, stimulus-driven) attention on performance. Internal states such as trait anxiety can also modulate the impact of attention on early visual processing. However, attention does not only improve performance; it also alters the way visual information appears to us, e.g. by enhancing perceived contrast. Here we show that emotion potentiates the effects of exogenous attention on both performance and perceived contrast. Moreover, we found that trait anxiety mediates these effects, with stronger influences of attention and emotion in anxious observers. Finally, changes in performance and appearance correlated with each other, likely reflecting common attentional modulations. Altogether, our findings show that emotion and anxiety interact with selective attention to truly alter how we see.

Correlation Between Measured Noise And Its Visual Perception.

NASA Astrophysics Data System (ADS)

Bollen, Romain

1986-06-01

For obvious reasons people in the field claim that measured data do not agree with what they perceive. Scientists reply by saying that their data are "true". Are they? Since images are made to be looked at, a request for data meaningful for what is perceived, is not foolish. We show that, when noise is characterized by standard density fluctuation figures, a good correlation with noise perception by the naked eye on a large size radiograph is obtained in applying microdensitometric scanning with a 400 micron aperture. For other viewing conditions the aperture size has to be adapted.

Size illusion, distance illusion, and terrestrial passage: comment on reed.

PubMed

Loftus, G R

1985-03-01

Two assumptions of Reed's (1984) terrestrial passage theory are questioned. First, Reed assumes that the moon's failure to increase in visual subtense while elevating is accounted for strictly by perceptual distancing. This allows a formal account of the moon distance illusion, but at the expense of a compelling explanation of the moon size illusion. Second, in order to explain the distance illusion, Reed assumes that all objects, regardless of their perceived altitude, are perceived to start from a common point at the horizon. Several alternative application of Reed's terrestrial-passage foundation to the actual illusions are suggested.

Resource Security Impacts Men’s Female Breast Size Preferences

PubMed Central

Swami, Viren; Tovée, Martin J.

2013-01-01

It has been suggested human female breast size may act as signal of fat reserves, which in turn indicates access to resources. Based on this perspective, two studies were conducted to test the hypothesis that men experiencing relative resource insecurity should perceive larger breast size as more physically attractive than men experiencing resource security. In Study 1, 266 men from three sites in Malaysia varying in relative socioeconomic status (high to low) rated a series of animated figures varying in breast size for physical attractiveness. Results showed that men from the low socioeconomic context rated larger breasts as more attractive than did men from the medium socioeconomic context, who in turn perceived larger breasts as attractive than men from a high socioeconomic context. Study 2 compared the breast size judgements of 66 hungry versus 58 satiated men within the same environmental context in Britain. Results showed that hungry men rated larger breasts as significantly more attractive than satiated men. Taken together, these studies provide evidence that resource security impacts upon men’s attractiveness ratings based on women’s breast size. PMID:23483919

Field Differences in the Use and Perceived Usefulness of Scholarly Mailing Lists

ERIC Educational Resources Information Center

Talja, Sanna; Savolainen, Reijo; Maula, Hanni

2004-01-01

Based on a qualitative comparative study across four domains, this paper explores how the use and perceived usefulness of scholarly mailing lists is related to primary search methods, collaboration patterns, loci of critical information, physical proximity of like-minded colleagues, field size, the desirability of sharing information in public or…

A subjective study and an objective metric to quantify the granularity level of textures

NASA Astrophysics Data System (ADS)

Subedar, Mahesh M.; Karam, Lina J.

2015-03-01

Texture granularity is an important visual characteristic that is useful in a variety of applications, including analysis, recognition, and compression, to name a few. A texture granularity measure can be used to quantify the perceived level of texture granularity. The granularity level of the textures is influenced by the size of the texture primitives. A primitive is defined as the smallest recognizable repetitive object in the texture. If the texture has large primitives then the perceived granularity level tends to be lower as compared to a texture with smaller primitives. In this work we are presenting a texture granularity database referred as GranTEX which consists of 30 textures with varying levels of primitive sizes and granularity levels. The GranTEX database consists of both natural and man-made textures. A subjective study is conducted to measure the perceived granularity level of textures present in the GranTEX database. An objective metric that automatically measures the perceived granularity level of textures is also presented as part of this work. It is shown that the proposed granularity metric correlates well with the subjective granularity scores.

Being Attractive Brings Advantages: The Case of Parrot Species in Captivity

PubMed Central

Frynta, Daniel; Lišková, Silvie; Bültmann, Sebastian; Burda, Hynek

2010-01-01

Background Parrots are one of the most frequently kept and bred bird orders in captivity. This increases poaching and thus the potential importance of captive populations for rescue programmes managed by zoos and related institutions. Both captive breeding and poaching are selective and may be influenced by the attractiveness of particular species to humans. In this paper, we tested the hypothesis that the size of zoo populations is not only determined by conservation needs, but also by the perceived beauty of individual parrot species assessed by human observers. Methodology/Principal Findings For the purpose of data collection, we defined four sets of species (40 parrots, 367 parrots, 34 amazons, 17 macaws). Then, we asked 776 human respondents to evaluate parrot pictures of the selected species according to perceived beauty and we analyzed its association with color and morphological characters. Irrespective of the species set, we found a good agreement among the respondents. The preferred species tended to be large, colorful, and long-tailed. Conclusions/Significance We repeatedly confirmed significant, positive association between the perceived beauty and the size of worldwide zoo population. Moreover, the range size and body size appeared to be significant predictors of zoo population size. In contrast, the effects of other explanatory variables, including the IUCN (International Union for Conservation of Nature) listing, appeared insignificant. Our results may suggest that zoos preferentially keep beautiful parrots and pay less attention to conservation needs. PMID:20830206

Size, skills, and suffrage: Motivated distortions in perceived formidability of political leaders

PubMed Central

Blaker, Nancy M.; Pollet, Thomas V.

2017-01-01

Research shows that perception of physical size and status are positively associated. The current study was developed to replicate and extend earlier research on height perceptions of political leaders, indicating that supporters perceive their leaders as taller than non-supporters do, and winners are perceived as taller after the elections, while losers are perceived as shorter after the elections (winner/loser effects). Individuals use greater height and strength as indications of greater physical formidability. We hypothesized that in-group leaders’ height and strength, but not weight, would be overestimated more compared to out-group leaders’, and that this status-size association is not only driven by dominance, but also by prestige. We also tested whether previously found gender effects in estimates were due to using one’s own height as an anchor, and we used an improved methodological approach by relying on multiple measurements of physical formidability and a within-subject design for testing winner/loser effects. The results of a two-part longitudinal study (self-selected sample via voting advice website; NWave1 = 2,011; NWave2 = 322) suggest that estimated physical formidability of political leaders is affected by motivated perception, as prestige was positively associated with estimated formidability, and in-group leaders were estimated more formidable than out-group leaders. We conclude that distortions in judged formidability related to social status are the result of motivated social perception in order to promote group functioning and leadership. Although we did not replicate a winner-effect (greater estimations of formidability after winning the elections), we did find some evidence for a loser-effect. Earlier suggestions that men make larger estimations than women because of their own larger body size are not supported. Implications for theory and future research are discussed. PMID:29267275

Visual-haptic integration with pliers and tongs: signal “weights” take account of changes in haptic sensitivity caused by different tools

PubMed Central

Takahashi, Chie; Watt, Simon J.

2014-01-01

When we hold an object while looking at it, estimates from visual and haptic cues to size are combined in a statistically optimal fashion, whereby the “weight” given to each signal reflects their relative reliabilities. This allows object properties to be estimated more precisely than would otherwise be possible. Tools such as pliers and tongs systematically perturb the mapping between object size and the hand opening. This could complicate visual-haptic integration because it may alter the reliability of the haptic signal, thereby disrupting the determination of appropriate signal weights. To investigate this we first measured the reliability of haptic size estimates made with virtual pliers-like tools (created using a stereoscopic display and force-feedback robots) with different “gains” between hand opening and object size. Haptic reliability in tool use was straightforwardly determined by a combination of sensitivity to changes in hand opening and the effects of tool geometry. The precise pattern of sensitivity to hand opening, which violated Weber's law, meant that haptic reliability changed with tool gain. We then examined whether the visuo-motor system accounts for these reliability changes. We measured the weight given to visual and haptic stimuli when both were available, again with different tool gains, by measuring the perceived size of stimuli in which visual and haptic sizes were varied independently. The weight given to each sensory cue changed with tool gain in a manner that closely resembled the predictions of optimal sensory integration. The results are consistent with the idea that different tool geometries are modeled by the brain, allowing it to calculate not only the distal properties of objects felt with tools, but also the certainty with which those properties are known. These findings highlight the flexibility of human sensory integration and tool-use, and potentially provide an approach for optimizing the design of visual-haptic devices. PMID:24592245

Effects of adding an Italian theme to a restaurant on the perceived ethnicity, acceptability, and selection of foods.

PubMed

Bell, R; Meiselman, H L; Pierson, B J; Reeve, W G

1994-02-01

We investigated whether a change in the perceived ethnicity of a food can be produced without manipulating the food item itself, and if that change in ethnic perception is accompanied by a change in acceptability and food selection behavior. Italian and British foods were offered in a British restaurant for four days. Foods were offered for 2 days under control conditions, when the restaurant was decorated as usual. The identical foods then were offered in the restaurant for 2 more days under experimental conditions, when ethnic names were used on the menu to describe foods, and the restaurant was decorated with an Italian theme. Perceived ethnicity and acceptability of items were rated by customers each day, and item selection was tracked. The Italian theme increased selection of pasta and dessert items, and decreased the selection of fish. The Italian theme also increased the perceived Italian ethnicity of British pasta items, fish and veal, and increased the perceived Italian ethnicity of the meal overall. These findings show that changes in perceived ethnicity and food selection can be accomplished without altering food items, but merely by manipulating the environment, and may imply a unique strategy for increasing perceived menu variety.

Drive for muscularity and social physique anxiety mediate the perceived ideal physique muscle dysmorphia relationship.

PubMed

Thomas, Adam; Tod, David A; Edwards, Christian J; McGuigan, Michael R

2014-12-01

This study examined the mediating role of drive for muscularity and social physique anxiety (SPA) in the perceived muscular male ideal physique and muscle dysmorphia relationship in weight training men. Men (N = 146, mean ± SD; age, 22.8 ± 5.0 years; weight, 82.0 ± 11.1 kg; height, 1.80 ± 0.07 m; body mass index, 25.1 ± 3.0) who participated in weight training completed validated questionnaires measuring drive for muscularity, SPA, perceived muscular male ideal physique, global muscle dysmorphia, and several characteristics of muscle dysmorphia (exercise dependence, diet manipulation, concerns about size/symmetry, physique protection behavior, and supplementation). Perceived ideal physique was an independent predictor of muscle dysmorphia measures except physique protection (coefficients = 0.113-0.149, p ≤ 0.05). Perceived ideal physique also predicted muscle dysmorphia characteristics (except physique protection and diet) through the indirect drive for muscularity pathway (coefficients = 0.055-0.116, p ≤ 0.05). Perceived ideal physique also predicted size/symmetry concerns and physique protection through the indirect drive for muscularity and SPA pathway (coefficients = 0.080-0.025, p ≤ 0.05). These results extend current research by providing insights into the way correlates of muscle dysmorphia interact to predict the condition. The results also highlight signs (e.g., anxiety about muscularity) that strength and conditioning coaches can use to identify at-risk people who may benefit from being referred for psychological assistance.

Perceived racial discrimination and hypertension: a comprehensive systematic review.

PubMed

Dolezsar, Cynthia M; McGrath, Jennifer J; Herzig, Alyssa J M; Miller, Sydney B

2014-01-01

Discrimination is posited to underlie racial disparities in hypertension. Extant literature suggests a possible association between racial discrimination and blood pressure, although inconsistent findings have been reported. The aim of this comprehensive systematic review was to quantitatively evaluate the association between perceived racial discrimination with hypertensive status and systolic, diastolic, and ambulatory blood pressure. Electronic database search of PubMed and PsycINFO (keywords: blood pressure/hypertension/diastolic/systolic, racism/discrimination/prejudice/unfair treatment) was combined with descendancy and ascendancy approaches. Forty-four articles (N = 32,651) met inclusion criteria. Articles were coded for demographics, hypertensive diagnosis, blood pressure measurement, discrimination measure and constructs, study quality, and effect sizes. Random effects meta-analytic models were tested based on Fisher's Z, the derived common effect size metric. Overall, perceived racial discrimination was associated with hypertensive status, Zhypertension = 0.048, 95% CI [.013, .087], but not with resting blood pressure, Zsystolic = 0.011, 95% CI [-.006, .031], Zdiastolic = .016, 95% CI [-.006, .034]. Moderators that strengthened the relation included sex (male), race (Black), age (older), education (lower), and hypertensive status. Perceived discrimination was most strongly associated with nighttime ambulatory blood pressure, especially among Blacks. Despite methodological limitations in the existing literature, there was a small, significant association between perceived discrimination and hypertension. Future studies should consider ambulatory nighttime blood pressure, which may more accurately capture daily variation attributable to experienced racial discrimination. Perceived discrimination may partly explain racial health disparities. 2014 APA, all rights reserved

Perceived Racial Discrimination and Hypertension: A Comprehensive Systematic Review

PubMed Central

Dolezsar, Cynthia M.; McGrath, Jennifer J.; Herzig, Alyssa J. M.; Miller, Sydney B.

2017-01-01

Objective Discrimination is posited to underlie racial disparities in hypertension. Extant literature suggests a possible association between racial discrimination and blood pressure, although inconsistent findings have been reported. The aim of this comprehensive systematic review was to quantitatively evaluate the association between perceived racial discrimination with hypertensive status and systolic, diastolic, and ambulatory blood pressure. Method Electronic database search of PubMed and PsycINFO (keywords: blood pressure/hypertension/diastolic/systolic, racism/discrimination/prejudice/unfair treatment) was combined with descendancy and ascendancy approaches. Forty-four articles (N = 32,651) met inclusion criteria. Articles were coded for demographics, hypertensive diagnosis, blood pressure measurement, discrimination measure and constructs, study quality, and effect sizes. Results Random effects meta-analytic models were tested based on Fisher’s Z, the derived common effect size metric. Overall, perceived racial discrimination was associated with hypertensive status, Zhypertension = 0.048, 95% CI [.013, .087], but not with resting blood pressure, Zsystolic = 0.011, 95% CI [−.006, .031], Zdiastolic = .016, 95% CI [−.006, .034]. Moderators that strengthened the relation included sex (male), race (Black), age (older), education (lower), and hypertensive status. Perceived discrimination was most strongly associated with nighttime ambulatory blood pressure, especially among Blacks. Conclusions Despite methodological limitations in the existing literature, there was a small, significant association between perceived discrimination and hypertension. Future studies should consider ambulatory nighttime blood pressure, which may more accurately capture daily variation attributable to experienced racial discrimination. Perceived discrimination may partly explain racial health disparities. PMID:24417692

What Makes a Caseload (Un) Manageable? School-Based Speech-Language Pathologists Speak

ERIC Educational Resources Information Center

Katz, Lauren A.; Maag, Abby; Fallon, Karen A.; Blenkarn, Katie; Smith, Megan K.

2010-01-01

Purpose: Large caseload sizes and a shortage of speech-language pathologists (SLPs) are ongoing concerns in the field of speech and language. This study was conducted to identify current mean caseload size for school-based SLPs, a threshold at which caseload size begins to be perceived as unmanageable, and variables contributing to school-based…

An Archer's Perceived Form Scales the "Hitableness" of Archery Targets

ERIC Educational Resources Information Center

Lee, Yang; Lee, Sih; Carello, Claudia; Turvey, M. T.

2012-01-01

For skills that involve hitting a target, subsequent judgments of target size correlate with prior success in hitting that target. We used an archery context to examine the judgment-success relationship with varied target sizes in the absence of explicit knowledge of results. Competitive archers shot at targets 50 m away that varied in size among…

Perceived Racism and Mental Health among Black American Adults: A Meta-Analytic Review

ERIC Educational Resources Information Center

Pieterse, Alex L.; Todd, Nathan R.; Neville, Helen A.; Carter, Robert T.

2012-01-01

The literature indicates that perceived racism tends to be associated with adverse psychological and physiological outcomes; however, findings in this area are not yet conclusive. In this meta-analysis, we systematically reviewed 66 studies (total sample size of 18,140 across studies), published between January 1996 and April 2011, on the…

An Association between College Students' Health Promotion Practices and Perceived Stress

ERIC Educational Resources Information Center

Li, Ying; Lindsey, Billie J.

2013-01-01

This study was undertaken to gain a better understanding of health promotion practices among college students and the relationship of stress and the practice of various health behaviors. Method: In Fall 2008, 319 students from a mid-size university participated in a cross-sectional survey utilizing the Perceived Stress Scale (PSS) and the Health…

Facial skin pores: a multiethnic study

PubMed Central

Flament, Frederic; Francois, Ghislain; Qiu, Huixia; Ye, Chengda; Hanaya, Tomoo; Batisse, Dominique; Cointereau-Chardon, Suzy; Seixas, Mirela Donato Gianeti; Dal Belo, Susi Elaine; Bazin, Roland

2015-01-01

Skin pores (SP), as they are called by laymen, are common and benign features mostly located on the face (nose, cheeks, etc) that generate many aesthetic concerns or complaints. Despite the prevalence of skin pores, related literature is scarce. With the aim of describing the prevalence of skin pores and anatomic features among ethnic groups, a dermatoscopic instrument, using polarized lighting, coupled to a digital camera recorded the major features of skin pores (size, density, coverage) on the cheeks of 2,585 women in different countries and continents. A detection threshold of 250 μm, correlated to clinical scorings by experts, was input into a specific software to further allow for automatic counting of the SP density (N/cm2) and determination of their respective sizes in mm2. Integrating both criteria also led to establishing the relative part of the skin surface (as a percentage) that is actually covered by SP on cheeks. The results showed that the values of respective sizes, densities, and skin coverage: 1) were recorded in all studied subjects; 2) varied greatly with ethnicity; 3) plateaued with age in most cases; and 4) globally refected self-assessment by subjects, in particular those who self-declare having “enlarged pores” like Brazilian women. Inversely, Chinese women were clearly distinct from other ethnicities in having very low density and sizes. Analyzing the present results suggests that facial skin pore’s morphology as perceived by human eye less result from functional criteria of associated appendages such as sebaceous glands. To what extent skin pores may be viewed as additional criteria of a photo-altered skin is an issue to be further addressed. PMID:25733918

Testing direct and moderating effects of coping styles on the relationship between perceived stress and antenatal anxiety symptoms.

PubMed

Lau, Ying; Wang, Yuqiong; Kwong, Dennis Ho Keung; Wang, Ying

2015-01-01

The objective of this study was to test the direct and moderating effects of different coping styles in mitigating perceived stress associated with antenatal anxiety symptoms among 755 pregnant women in Chengdu. A cross-sectional study using a questionnaire survey was carried out. The Perceived Stress Scale, the Trait Coping Style Questionnaire and the Zung Self-rating Anxiety Scale were used to measure stress, coping and anxiety symptoms, respectively. Hierarchical regression analysis was used to test the direct and moderating effects of coping styles in the relationship between perceived stress and antenatal anxiety symptoms. Direct effects of negative coping (NC) styles were found. Women with higher NC scores were more likely to have anxiety symptoms. Positive coping (PC) styles had moderating effects on perceived stress, whereas NC styles did not. The findings of this study highlight the direct and moderating effects of coping styles. This knowledge is important to healthcare professionals in planning health service provision. Health services should dedicate resources to teaching pregnant women how to enhance PC styles, alter NC styles and cultivate optimistic thinking to alleviate anxiety symptoms.

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...

Validation of French and German versions of a Perceived Neighborhood Social Cohesion Questionnaire among young Swiss males, and its relationship with substance use.

PubMed

Dupuis, Marc; Studer, Joseph; Henchoz, Yves; Deline, Stéphane; Baggio, Stéphanie; N'Goran, Alexandra; Mohler-Kuo, Meichun; Gmel, Gerhard

2016-02-01

This study main purpose was the validation of both French and German versions of a Perceived Neighborhood Social Cohesion Questionnaire. The sample group comprised 5065 Swiss men from the "Cohort Study on Substance Use Risk Factors." Multigroup Confirmatory factor analysis showed that a three-factor model fits the data well, which substantiates the generalizability of Perceived Neighborhood Social Cohesion Questionnaire factor structure, regardless of the language. The Perceived Neighborhood Social Cohesion Questionnaire demonstrated excellent homogeneity (α = 95) and split-half reliability (r = .96). The Perceived Neighborhood Social Cohesion Questionnaire was sensitive to community size and participants' financial situation, confirming that it also measures real social conditions. Finally, weak but frequent correlations between Perceived Neighborhood Social Cohesion Questionnaire and alcohol, cigarette, and cannabis dependence were measured. © The Author(s) 2014.

The Effect of Furnishing on Perceived Spatial Dimensions and Spaciousness of Interior Space

PubMed Central

von Castell, Christoph; Oberfeld, Daniel; Hecht, Heiko

2014-01-01

Despite the ubiquity of interior space design, there is virtually no scientific research on the influence of furnishing on the perception of interior space. We conducted two experiments in which observers were asked to estimate the spatial dimensions (size of the room dimensions in meters and centimeters) and to judge subjective spaciousness of various rooms. Experiment 1 used true-to-scale model rooms with a square surface area. Furnishing affected both the perceived height and the spaciousness judgments. The furnished room was perceived as higher but less spacious. In Experiment 2, rooms with different square surface areas and constant physical height were presented in virtual reality. Furnishing affected neither the perceived spatial dimensions nor the perceived spaciousness. Possible reasons for this discrepancy, such as the influence of the presentation medium, are discussed. Moreover, our results suggest a compression of perceived height and depth with decreasing surface area of the room. PMID:25409456

The effect of furnishing on perceived spatial dimensions and spaciousness of interior space.

PubMed

von Castell, Christoph; Oberfeld, Daniel; Hecht, Heiko

2014-01-01

Despite the ubiquity of interior space design, there is virtually no scientific research on the influence of furnishing on the perception of interior space. We conducted two experiments in which observers were asked to estimate the spatial dimensions (size of the room dimensions in meters and centimeters) and to judge subjective spaciousness of various rooms. Experiment 1 used true-to-scale model rooms with a square surface area. Furnishing affected both the perceived height and the spaciousness judgments. The furnished room was perceived as higher but less spacious. In Experiment 2, rooms with different square surface areas and constant physical height were presented in virtual reality. Furnishing affected neither the perceived spatial dimensions nor the perceived spaciousness. Possible reasons for this discrepancy, such as the influence of the presentation medium, are discussed. Moreover, our results suggest a compression of perceived height and depth with decreasing surface area of the room.

The impact of self-reported psychological stress levels on changes to peripheral blood immune biomarkers in recreational marathon runners during training and recovery.

PubMed

Rehm, Kristina E; Elci, Okan U; Hahn, Kathryn; Marshall, Gailen D

2013-01-01

Marathon training is both physically and psychologically stressful, both of which can lead to altered immunity. The purpose of this study was to determine if the overall immunoregulatory changes associated with the physical stress of marathon training are affected by psychological stress. Nineteen recreational marathoners completed the Perceived Stress Scale (PSS), State-Trait Anxiety Inventory (STAI) and Penn State Worry Questionnaire (PSWQ), and had levels of T cell subpopulations and cytokine (IFNγ, IL4 and IL10) production determined 4 weeks before (baseline), 24-48 h before (prerace) and 1 week after (recovery) participation in a marathon. PSS scores decreased at the prerace visit compared to baseline and remained low at recovery. Compared to baseline, there were significant changes to numerous immune measures at the prerace visit, including decreases in Th1/Th2 ratio, Tc1/Tc2 ratio, Tr1 and Th3 cell populations as well as decreases in IFNγ/IL4 cytokine ratio and IL10 production. Most immune parameters had returned to near baseline values at the recovery visit. Higher levels of perceived stress, anxiety and worry exacerbated many of the alterations in immunity that were observed at the prerace visit. Higher levels of perceived stress and worry had significant effects on changes to Treg, IL4 production and the IFNγ/IL4 cytokine ratio. Stress had an additional impact on changes in IL10 production. High anxiety levels resulted in significant changes to Treg, Tr1 and Th3. These data suggest that recreational marathon runners with higher levels of psychological stress may be more at risk for the immune alterations that are common during periods of prolonged physical training. Copyright © 2013 S. Karger AG, Basel.

Long-term support and personal adjustment of adolescent and older mothers.

PubMed

Schilmoeller, G L; Baranowski, M D; Higgins, B S

1991-01-01

Adolescent and older mothers reported the size and quality of social networks and perceptions of family support at 1, 6, and 12 months postpartum. Maternal behavior, general life satisfaction, and parental satisfaction were assessed at 12 months. No significant differences were found in the size of social networks and quality of interactions within those networks, though older mothers had significantly higher scores on perceived family support than did adolescent mothers. Perceived family support and quality of interactions within the social network generally were associated positively with maternal behavior, life satisfaction, and parental satisfaction. This was true in more cases for the adolescent than for older mothers.

Overestimation of heights in virtual reality is influenced more by perceived distal size than by the 2-D versus 3-D dimensionality of the display.

PubMed

Dixon, Melissa W; Proffitt, Dennis R

2002-01-01

One important aspect of the pictorial representation of a scene is the depiction of object proportions. Yang, Dixon, and Proffitt (1999 Perception 28 445-467) recently reported that the magnitude of the vertical-horizontal illusion was greater for vertical extents presented in three-dimensional (3-D) environments compared to two-dimensional (2-D) displays. However, because all of the 3-D environments were large and all of the 2-D displays were small, the question remains whether the observed magnitude differences were due solely to the dimensionality of the displays (2-D versus 3-D) or to the perceived distal size of the extents (small versus large). We investigated this question by comparing observers' judgments of vertical relative to horizontal extents on a large but 2-D display compared to the large 3-D and the small 2-D displays used by Yang et al (1999). The results confirmed that the magnitude differences for vertical overestimation between display media are influenced more by the perceived distal object size rather than by the dimensionality of the display.

Overestimation of heights in virtual reality is influenced more by perceived distal size than by the 2-D versus 3-D dimensionality of the display

NASA Technical Reports Server (NTRS)

Dixon, Melissa W.; Proffitt, Dennis R.; Kaiser, M. K. (Principal Investigator)

2002-01-01

One important aspect of the pictorial representation of a scene is the depiction of object proportions. Yang, Dixon, and Proffitt (1999 Perception 28 445-467) recently reported that the magnitude of the vertical-horizontal illusion was greater for vertical extents presented in three-dimensional (3-D) environments compared to two-dimensional (2-D) displays. However, because all of the 3-D environments were large and all of the 2-D displays were small, the question remains whether the observed magnitude differences were due solely to the dimensionality of the displays (2-D versus 3-D) or to the perceived distal size of the extents (small versus large). We investigated this question by comparing observers' judgments of vertical relative to horizontal extents on a large but 2-D display compared to the large 3-D and the small 2-D displays used by Yang et al (1999). The results confirmed that the magnitude differences for vertical overestimation between display media are influenced more by the perceived distal object size rather than by the dimensionality of the display.

Effect of Display Technology on Perceived Scale of Space.

PubMed

Geuss, Michael N; Stefanucci, Jeanine K; Creem-Regehr, Sarah H; Thompson, William B; Mohler, Betty J

2015-11-01

Our goal was to evaluate the degree to which display technologies influence the perception of size in an image. Research suggests that factors such as whether an image is displayed stereoscopically, whether a user's viewpoint is tracked, and the field of view of a given display can affect users' perception of scale in the displayed image. Participants directly estimated the size of a gap by matching the distance between their hands to the gap width and judged their ability to pass unimpeded through the gap in one of five common implementations of three display technologies (two head-mounted displays [HMD] and a back-projection screen). Both measures of gap width were similar for the two HMD conditions and the back projection with stereo and tracking. For the displays without tracking, stereo and monocular conditions differed from each other, with monocular viewing showing underestimation of size. Display technologies that are capable of stereoscopic display and tracking of the user's viewpoint are beneficial as perceived size does not differ from real-world estimates. Evaluations of different display technologies are necessary as display conditions vary and the availability of different display technologies continues to grow. The findings are important to those using display technologies for research, commercial, and training purposes when it is important for the displayed image to be perceived at an intended scale. © 2015, Human Factors and Ergonomics Society.

Manipulating stereopsis and vergence in an outdoor setting: moon, sky and horizon.

PubMed

Enright, J T

1989-01-01

A simple stimulus generator has been constructed that permits a small illuminated target to be seen with variable inter-ocular disparity, when superimposed upon the binocular view of an outdoor landscape. This device was applied to several questions involving perception of size, distance and orientation, with the following results: (1) when the apparent distance to an "artificial moon", as perceived through stereopsis, is decreased by about 50-fold (from near horizon to about 60 m), its apparent size is reduced by only a miniscule amount (8% on average); hence, the moon illusion is probably not due to compensation--conscious or subconscious--for its apparent distance; (2) those changes in apparent size known as convergence micropsia vary as a function of the visual surround; for a vergence change of 1 deg, greater perceived change in size of a small target arises when a landscape is seen nearby than with empty sky as surround; (3) when a target is shown somewhat above the horizon against an empty sky, it must be viewed with divergence of the visual axes (image positions for "hyper-infinite" distance), in order to be perceived as vertically above objects on the skyline; this effect implies a strong backward tilt to the apparent vertical and probably reflects an attempt to "null out" the perceptual consequences of the convergence that typically occurs during downward saccades.

Hardness and posting of foot orthoses modify plantar contact area, plantar pressure, and perceived comfort when cycling.

PubMed

Bousie, Jaquelin A; Blanch, Peter; McPoil, Thomas G; Vicenzino, Bill

2018-07-01

To evaluate the effects of hardness and posting of orthoses on plantar profile and perceived comfort and support during cycling. A repeated measures study with randomised order of orthoses, hardness, and posting conditions. Twenty-three cyclists cycled at a cadence of 90rpm and a perceived exertion rating of twelve. Contoured soft and hard orthoses with or without a medial forefoot or lateral forefoot post were evaluated. Plantar contact area, mean pressure and peak pressure were measured for nine plantar regions using the pedar ® -X system and represented as a percentage of the total (CA%, MP%, and PP% respectively). Perceived comfort and support was rated on a visual analogue scale. The softer orthosis significantly increased CA% (p=0.014) across the midfoot and heel with a decrease in the toe region and forefoot. MP% (p=0.034) and PP% (p=0.012) were significantly increased at the mid and lateral forefoot with reductions in MP% at the midfoot and in PP% at the hallux and toes. Forefoot posting significantly increased CA% (p=0.018) at the toes and forefoot and decreased it at the heel. PP% was significantly altered (p=0.013) based on posting position. Lateral forefoot posting significantly decreased heel comfort (p=0.036). When cycling, a soft, contoured orthosis increased contact across the midfoot and heel, modulating forefoot and midfoot plantar pressures but not altering comfort or support. Forefoot postings significantly modified contact areas and plantar pressures and reduced comfort at the heel. Copyright © 2017. Published by Elsevier Ltd.

Four-flux model of the light scattering in porous varnish and paint layers: towards understanding the visual appearance of altered blanched easel oil paintings

NASA Astrophysics Data System (ADS)

Genty-Vincent, Anaïs; Van Song, Théo Phan; Andraud, Christine; Menu, Michel

2017-07-01

Blanching of easel oil paintings is a recurring alteration that can affect the varnish layer and also the paint layer itself, and strongly alter the visual appearance. Our examinations by field emission gun scanning electron microscopy (FEG-SEM) of altered and unaltered samples revealed the presence of spherical pores in the altered layers, with a pore size ranging from few nanometers to few micrometers. The aim of the present study is to corroborate that the visual appearance modification can be explained by light scattering theories (Mie or Rayleigh depending on the pore size of the considered layer). The four-flux model was used to resolve the radiative transfer equation (RTE) and model the light scattering in porous varnish layers as well as in porous green earth and raw umber oil paint layers. It enables to highlight that the pore size has an important impact on the visual appearance of the altered layer (color and opacity modification). The pore concentration and the thickness of the altered part affect, however, only the opacity. This work points out that the blanching of easel oil paintings is due to light scattering by the pores, which is an important result toward the proposal of adapted and durable future conservation treatments.

Characterizing visual asymmetries in contrast perception using shaded stimuli.

PubMed

Chacón, José; Castellanos, Miguel Ángel; Serrano-Pedraza, Ignacio

2015-01-01

Previous research has shown a visual asymmetry in shaded stimuli where the perceived contrast depended on the polarity of their dark and light areas (Chacón, 2004). In particular, circles filled out with a top-dark luminance ramp were perceived with higher contrast than top-light ones although both types of stimuli had the same physical contrast. Here, using shaded stimuli, we conducted four experiments in order to find out if the perceived contrast depends on: (a) the contrast level, (b) the type of shading (continuous vs. discrete) and its degree of perceived three-dimensionality, (c) the orientation of the shading, and (d) the sign of the perceived contrast alterations. In all experiments the observers' tasks were to equate the perceived contrast of two sets of elements (usually shaded with opposite luminance polarity), in order to determine the subjective equality point. Results showed that (a) there is a strong difference in perceived contrast between circles filled out with luminance ramp top-dark and top-light that is similar for different contrast levels; (b) we also found asymmetries in contrast perception with different shaded stimuli, and this asymmetry was not related with the perceived three-dimensionality but with the type of shading, being greater for continuous-shading stimuli; (c) differences in perceived contrast varied with stimulus orientation, showing the maximum difference on vertical axis with a left bias consistent with the bias found in previous studies that used visual-search tasks; and (d) asymmetries are consistent with an attenuation in perceived contrast that is selective for top-light vertically-shaded stimuli.

Seeing big things: overestimation of heights is greater for real objects than for objects in pictures

NASA Technical Reports Server (NTRS)

Yang, T. L.; Dixon, M. W.; Proffitt, D. R.; Kaiser, M. K. (Principal Investigator)

1999-01-01

In six experiments we demonstrate that the vertical-horizontal illusion that is evoked when viewing photographs and line drawings is relatively small, whereas the magnitude of this illusion when large objects are viewed is at least twice as great. Furthermore, we show that the illusion is due more to vertical overestimation than horizontal underestimation. The lack of a difference in vertical overestimation between pictures and line drawings suggests that vertical overestimation in pictures depends solely on the perceived physical size of the projection on the picture surface, rather than on what is apparent about an object's represented size. The vertical-horizontal illusion is influenced by perceived physical size. It is greater when viewing large objects than small pictures of these same objects, even when visual angles are equated.

Majority Group Members' Negative Reactions to Future Demographic Shifts Depend on the Perceived Legitimacy of Their Status: Findings from the United States and Portugal.

PubMed

Outten, H Robert; Lee, Timothy; Costa-Lopes, Rui; Schmitt, Michael T; Vala, Jorge

2018-01-01

Using concepts from social identity theory (Tajfel and Turner, 1979), we examined whether racial/ethnic majority group members' reactions to future demographic shifts is a function of the degree to which they perceive their ingroup's higher-status in society to be legitimate. In two studies, participants who varied in the degree to which they perceived their group's status to be legitimate were either exposed to real projections for 2060 (i.e., large decline in proportion of population that is the "majority" group), or fake projections for 2060-that resembled current figures (i.e., small decline). In Study 1, White Americans who perceived their status to be highly legitimate expressed greater intergroup threat, and negative feelings (anger and fear) toward minorities after exposure to projections with a large decline in the relative size of the White American population. In contrast, demographic shift condition had no effect on intergroup threat and negative feelings toward minorities among White Americans who perceived their status to be relatively illegitimate; negative feelings and threat remained low across both conditions. Similarly, in Study 2, ethnic Portuguese people in Portugal exposed to projections in which there was a large decline in the relative size of the ethnic Portuguese population experienced more intergroup threat and expressed a greater desire to engage in anti-immigration behaviors. The effect of demographic shift condition on intergroup threat and anti-immigration behaviors was stronger among ethnic Portuguese who perceived their status to be legitimate compared to ethnic Portuguese people who perceived their status to be relatively illegitimate. These results highlight that across different cultural contexts, majority group members' beliefs about the legitimacy of intergroup relations can affect their reactions to the prospect of increased diversity.

Blood Oxygen Level-Dependent Activation of the Primary Visual Cortex Predicts Size Adaptation Illusion

PubMed Central

Pooresmaeili, Arezoo; Arrighi, Roberto; Biagi, Laura; Morrone, Maria Concetta

2016-01-01

In natural scenes, objects rarely occur in isolation but appear within a spatiotemporal context. Here, we show that the perceived size of a stimulus is significantly affected by the context of the scene: brief previous presentation of larger or smaller adapting stimuli at the same region of space changes the perceived size of a test stimulus, with larger adapting stimuli causing the test to appear smaller than veridical and vice versa. In a human fMRI study, we measured the blood oxygen level-dependent activation (BOLD) responses of the primary visual cortex (V1) to the contours of large-diameter stimuli and found that activation closely matched the perceptual rather than the retinal stimulus size: the activated area of V1 increased or decreased, depending on the size of the preceding stimulus. A model based on local inhibitory V1 mechanisms simulated the inward or outward shifts of the stimulus contours and hence the perceptual effects. Our findings suggest that area V1 is actively involved in reshaping our perception to match the short-term statistics of the visual scene. PMID:24089504

Quorum-quenching limits quorum-sensing exploitation by signal-negative invaders

USDA-ARS?s Scientific Manuscript database

Some bacteria produce and perceive quorum-sensing (QS) signals that coordinate several behaviors, including the physiologically costly processes of exoenzyme production and plasmid transfer. In the case of plasmid transfer, the emergence of QS signal-altered invaders and their policing are poorly do...

The effects of social identity threat and social identity affirmation on laypersons' perception of scientists.

PubMed

Nauroth, Peter; Gollwitzer, Mario; Kozuchowski, Henrik; Bender, Jens; Rothmund, Tobias

2017-10-01

Public debates about socio-scientific issues (e.g. climate change or violent video games) are often accompanied by attacks on the reputation of the involved scientists. Drawing on the social identity approach, we report a minimal group experiment investigating the conditions under which scientists are perceived as non-prototypical, non-reputable, and incompetent. Results show that in-group affirming and threatening scientific findings (compared to a control condition) both alter laypersons' evaluations of the study: in-group affirming findings lead to more positive and in-group threatening findings to more negative evaluations. However, only in-group threatening findings alter laypersons' perceptions of the scientists who published the study: scientists were perceived as less prototypical, less reputable, and less competent when their research results imply a threat to participants' social identity compared to a non-threat condition. Our findings add to the literature on science reception research and have implications for understanding the public engagement with science.

Gender stereotype-consistent memories: How system justification motivation distorts the recollection of information related to the self.

PubMed

Bonnot, Virginie; Krauth-Gruber, Silvia

2018-01-01

Research based on system justification theory has shown that women's self-perceptions may be altered by the motivation to justify the system and its inequalities. Self-perceptions being built on past experiences, the present study aimed to explore how system justification motivation induced through a system dependency manipulation may alter both women's recall of autobiographical memories and their behavior. Women who were led to feel highly dependent on the social system perceived themselves as more competent and recalled memories of higher competence in the verbal domain compared with the negatively stereotyped scientific domain. Women's behavioral choices (between doing a verbal or a math exercise) also revealed a higher preference for the gender stereotype-consistent verbal exercise in the high-system dependency condition, as compared with the low-system dependency condition. These results suggest that gender stereotypes may not only satisfy self- or group-serving motivation but also the need to perceive the system in a positive light.

Back from the future: Volitional postdiction of perceived apparent motion direction.

PubMed

Sun, Liwei; Frank, Sebastian M; Hartstein, Kevin C; Hassan, Wassim; Tse, Peter U

2017-11-01

Among physical events, it is impossible that an event could alter its own past for the simple reason that past events precede future events, and not vice versa. Moreover, to do so would invoke impossible self-causation. However, mental events are constructed by physical neuronal processes that take a finite duration to execute. Given this fact, it is conceivable that later brain events could alter the ongoing interpretation of previous brain events if they arrive within this finite duration of interpretive processing, before a commitment is made to what happened. In the current study, we show that humans can volitionally influence how they perceive an ambiguous apparent motion sequence, as long as the top-down command occurs up to 300ms after the occurrence of the actual motion event in the world. This finding supports the view that there is a temporal integration period over which perception is constructed on the basis of both bottom-up and top-down inputs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Contact Instrument Calibration Targets on Mars Rover Curiosity

NASA Image and Video Library

2012-02-07

Two instruments at the end of the robotic arm on NASA Mars rover Curiosity will use calibration targets attached to a shoulder joint of the arm. The penny is a size reference giving the public a familiar object for perceiving size on Mars easily.

Dietary Habits and Body Size Perception of Elementary School Children

ERIC Educational Resources Information Center

Murimi, Mary W.

2004-01-01

This study assessed the attitudes and concerns of children in grades 1 through 5 regarding their perceived body size and ideal body size, and it assessed their Body Mass Index (BMI) and dietary habits. This study found an overweight prevalence of 11.4%, based on the children's BMI. Most of the overweight students were either African American or…

Update on the recommended viewing protocol for FAXIL threshold contrast detail detectability test objects used in television fluoroscopy.

PubMed

Launders, J H; McArdle, S; Workman, A; Cowen, A R

1995-01-01

The significance of varying the viewing conditions that may affect the perceived threshold contrast of X-ray television fluoroscopy systems has been investigated. Factors investigated include the ambient room lighting and the viewing distance. The purpose of this study is to find the optimum viewing protocol with which to measure the threshold detection index. This is a particular problem when trying to compare the image quality of television fluoroscopy systems in different input field sizes. The results show that the viewing distance makes a significant difference to the perceived threshold contrast, whereas the ambient light conditions make no significant difference. Experienced observers were found to be capable of finding the optimum viewing distance for detecting details of each size, in effect using a flexible viewing distance. This allows the results from different field sizes to be normalized to account for both the magnification and the entrance air kerma rate differences, which in turn allow for a direct comparison of performance in different field sizes.

Juvenile exposure to predator cues induces a larger egg size in fish

PubMed Central

Segers, Francisca H. I. D.; Taborsky, Barbara

2012-01-01

When females anticipate a hazardous environment for their offspring, they can increase offspring survival by producing larger young. Early environmental experience determines egg size in different animal taxa. We predicted that a higher perceived predation risk by juveniles would cause an increase in the sizes of eggs that they produce as adults. To test this, we exposed juveniles of the mouthbrooding cichlid Eretmodus cyanostictus in a split-brood experiment either to cues of a natural predator or to a control situation. After maturation, females that had been confronted with predators produced heavier eggs, whereas clutch size itself was not affected by the treatment. This effect cannot be explained by a differential female body size because the predator treatment did not influence growth trajectories. The observed increase of egg mass is likely to be adaptive, as heavier eggs gave rise to larger young and in fish, juvenile predation risk drops sharply with increasing body size. This study provides the first evidence that predator cues perceived by females early in life positively affect egg mass, suggesting that these cues allow her to predict the predation risk for her offspring. PMID:21976689

Alterations of male sexual behavior by learned aversions to hamster vaginal secretion.

PubMed

Johnston, R E; Zahorik, D M; Immler, K; Zakon, H

1978-02-01

Male hamsters poisoned after their first adult exposure to the vaginal secretion of female hamsters became hesitant to approach and ingest the secretion. The same aversion-training procedure also altered the responses of males to estrous females, changing the latency, frequency, and duration of a variety of behaviors that are commonly taken as indexes of sexual attraction or arousal and of copulatory performance. The effects suggest that the aversions to vaginal secretion alter the perceived meaning of the secretion for male hamsters, and analysis of the correlations between various measures of sexual arousal and performance support the hypothesis that separate mechanisms underlie the effects of the secretion on appetitive and consummatory sexual behavior.

The predictive role of health-promoting behaviours and perceived stress in aneurysmal rupture.

PubMed

Lee, Mi-Sun; Park, Chang G; Hughes, Tonda L; Jun, Sang-Eun; Whang, Kum; Kim, Nahyun

2018-03-01

To examine the roles of two modifiable factors-health-promoting behaviours and perceived stress-in predicting aneurysmal rupture. Unruptured intracranial aneurysm detection produces significant stress and anxiety in patients because of the risk of rupture. Compared to nonmodifiable risk factors for rupture such as age, gender and aneurysm size/location, less attention has been given to modifiable risk factors. Two modifiable factors, health-promoting behaviours and perceived stress, have hardly been examined as potential predictors of rupture. This study used a cross-sectional design. We assessed 155 patients with intracranial aneurysms-that is, subarachnoid haemorrhage (n = 77) or unruptured intracranial aneurysm (n = 78)-to examine (i) baseline characteristics (patient and aneurysmal factors), (ii) health-related factors (lifestyle habits and health-promoting behaviour) and (iii) perceived stress levels (psychological stress and physical stress). Patient records provided medical histories and aneurysmal factors; other data were collected using a structured questionnaire addressing lifestyle habits, the Health-Promoting Lifestyle Profile-II to measure health-promoting behaviour and the Perceived Stress Questionnaire to measure perceived-psychological stress and perceived-physical stress levels. Bivariate analysis indicated that aneurysm rupture risk was associated with female gender, aneurysm size/location, defecation frequency, hyperlipidaemia, sedentary time, low Health-Promoting Lifestyle Profile-II mean scores and high perceived-psychological stress scores. After adjusting for known risk factors, the mean Health-Promoting Lifestyle Profile-II and perceived-psychological stress scores remained robust predictors of rupture. Furthermore, known risk factors combined with these scores had greater predictive power than known risk factors alone. Health-promoting behaviour and psychological stress are promising modifiable factors for reducing risk of aneurysmal rupture. Our findings may stimulate greater understanding of mechanisms underlying aneurysmal rupture and suggest practical strategies for nurses to employ in optimising conservative management of rupture risk by teaching patients how to modify their risk. Both health-promoting behaviour and perceived stress should be addressed when designing preventive nursing interventions for patients with unruptured intracranial aneurysm. © 2017 John Wiley & Sons Ltd.

Size and distance are perceived independently in an optical tunnel: Evidence for direct perception.

PubMed

Kim, Seokhun; Carello, Claudia; Turvey, Michael T

2016-08-01

The historical but questionable size-distance invariance hypothesis (SDIH) features computation over geometric, oculomotor, and binocular cues and the coupling of percepts-perceived size, S', is mediated by perceived distance, D'. A contemporary non-mediational hypothesis holds that S' and D' are specific to distinct optical variables. We report two experiments with an optical tunnel, an arrangement of alternating black and white concentric rings, that allows systematic manipulation of the optic array at a point of observation while controlling a variety of size and depth cues. Participants viewed targets of different sizes at different distances monocularly, reporting S' and D' via magnitude production. In Experiment 1, the target was either placed in a continuous tunnel (extending 164cm) or in a tunnel that truncated at the target's location. Experiment 2 included a third tunnel, one that was truncated with a flat depiction of the posterior surface structure that would have been visible in the continuous tunnel. In both experiments, S' decreased with D but D' was unaffected by S. Partial correlation analyses showed that the relationship between S' and D' was not significant when the contributions of other variables were removed. Importantly, S' and D' were affected differently by manipulations of the optical tunnel's continuity while computationally obvious visual cues were controlled. These outcomes suggest that D' is not a mediator of S'. Rather S' and D' are independently determined with correlated but different optical bases, results that support the direct model. Copyright © 2016 Elsevier Ltd. All rights reserved.

Adolescents' reactions to universal and indicated prevention programs for depression: perceived stigma and consumer satisfaction.

PubMed

Rapee, Ronald M; Wignall, Ann; Sheffield, Jeanie; Kowalenko, Nick; Davis, Anna; McLoone, Jordana; Spence, Susan H

2006-06-01

There is a common view that one of the major considerations in selecting between universal and indicated interventions is the marked stigma produced by the latter. However, to date there has been no empirical examination of this assumption. The current study examined reported stigma and program satisfaction following two school-based interventions aimed at preventing depression in 532 middle adolescents. The interventions were conducted either across entire classes by classroom teachers (universal delivery) or in small high risk groups by mental health professionals (indicated delivery). The indicated delivery was associated with significantly greater levels of perceived stigma, but effect sizes were small and neither program was associated with marked stigma in absolute terms. Perceived stigma was more strongly associated with aspects of the individual including being male and showing greater externalizing symptomatology. In contrast, the indicated program was evaluated more positively by both participants and program leaders and effect sizes for these measures of satisfaction were moderate to large. The results point to the need for further empirical evaluation of both perceived stigma and program satisfaction in providing balanced considerations of the value of indicated and universal programs.

Willingness to participate in accountable care organizations: health care managers' perspective.

PubMed

Wan, Thomas T H; Demachkie Masri, Maysoun; Ortiz, Judith; Lin, Blossom Y J

2014-01-01

This study examines how health care managers responded to the accountable care organization (ACO). The effect of perceived benefits and barriers of the commitment to develop a strategic plan for ACOs and willingness to participate in ACOs is analyzed, using organizational social capital, health information technology uses, health systems integration and size of the health networks, geographic factors, and knowledge about ACOs as predictors. Propensity score matching and analysis are used to adjust the state and regional variations. When the number of perceived benefits is greater than the number of perceived barriers, health care managers are more likely to reveal a stronger commitment to develop a strategic plan for ACO adoption. Health care managers who perceived their organizations as lacking leadership support or commitment, financial incentives, and legal and regulatory support to ACO adoption were less willing to participate in ACOs in the future. Future research should gather more diverse views from a larger sample size of health professionals regarding ACO participation. The perspective of health care managers should be seriously considered in the adoption of an innovative health care delivery system. The transparency on policy formulation should consider multiple views of health care managers.

Warming alters community size structure and ecosystem functioning

PubMed Central

Dossena, Matteo; Yvon-Durocher, Gabriel; Grey, Jonathan; Montoya, José M.; Perkins, Daniel M.; Trimmer, Mark; Woodward, Guy

2012-01-01

Global warming can affect all levels of biological complexity, though we currently understand least about its potential impact on communities and ecosystems. At the ecosystem level, warming has the capacity to alter the structure of communities and the rates of key ecosystem processes they mediate. Here we assessed the effects of a 4°C rise in temperature on the size structure and taxonomic composition of benthic communities in aquatic mesocosms, and the rates of detrital decomposition they mediated. Warming had no effect on biodiversity, but altered community size structure in two ways. In spring, warmer systems exhibited steeper size spectra driven by declines in total community biomass and the proportion of large organisms. By contrast, in autumn, warmer systems had shallower size spectra driven by elevated total community biomass and a greater proportion of large organisms. Community-level shifts were mirrored by changes in decomposition rates. Temperature-corrected microbial and macrofaunal decomposition rates reflected the shifts in community structure and were strongly correlated with biomass across mesocosms. Our study demonstrates that the 4°C rise in temperature expected by the end of the century has the potential to alter the structure and functioning of aquatic ecosystems profoundly, as well as the intimate linkages between these levels of ecological organization. PMID:22496185

Impacts of casinos on key pathways to health: qualitative findings from American Indian gaming communities in California.

PubMed

Kodish, Stephen R; Gittelsohn, Joel; Oddo, Vanessa M; Jones-Smith, Jessica C

2016-07-22

Three decades ago, casino gaming on sovereign American Indian lands was legalized with differential economic and social implications. While casinos have improved the incomes of tribal communities, there have been both positive and negative findings in relation to health impacts. We sought to understand the perceived pathways by which casinos impact individual and community health through voices of the community. We conducted semi-structured, interviews with tribal leaders (n =12) and tribal members (n =24) from tribal communities (n = 23) representing different regions of California. We inductively analyzed textual data drawing from Grounded Theory, first using line-by-line coding to identify analytic categories from emergent themes in consideration of the study objective. Then, focused codes were applied to identify salient themes, which we represented through exemplar quotes and an overall conceptual framework. Data were managed and coded using Dedoose software. American Indian-owned casinos are perceived to influence the health of tribal communities through three pathways: 1) improving the tribal economy 2) altering the built environment, and 3) disrupting the the social landscape. Forming these pathways are a series of interrelated health determinants. Improvement of the tribal economy, through both job creation for tribal members and improved tribal cash flow, was perceived by participants to both influence health. Specifically, improved cash flow has resulted in new wellness programs, community centers, places for recreation, and improved social services. Higher disposable incomes have led to better financial stability, increased access to healthy food, and more opportunities for physical activity. Yet, higher disposable incomes were perceived to also contribute to negative health behaviors, most notably increased drug and alcohol abuse. Casinos were also perceived to alter built environments, resulting in increased availability and access to unhealthy food. And to a lesser extent, they were perceived to disrupt the social landscape of communities with impacts on tribal community value systems. Casino environments improve economic conditions of tribal communities, but present important social and public health challenges. Policy makers at federal, state, and tribal levels should consider the perceptions of tribal members and leaders when determining policies in light of casino development.

Extending Research on Oral Reading Fluency Measures, Reading Speed, and Comprehension

ERIC Educational Resources Information Center

Schall, Megan; Skinner, Christopher H.; Cazzell, Samantha; Ciancio, Dennis; Ruddy, Jonah; Thompson, Kelly

2016-01-01

Middle-school students completed a comprehension assessment. The following day, they read four, 120-word passages, two standard and two non-standard ransom-note passages with altered font sizes. Altering font sizes increased students' reading time (i.e., reduced reading speed) by an average of 3 s and decreased students' words correct per minute…

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

EPA Science Inventory

The estrogenic and antiandrogenic pesticide methoxychlor alters the reproductive tract and behavior without affecting pituitary size or LH and prolactin secretion in male rats.

Gray LE Jr, Ostby J, Cooper RL, Kelce WR.

Endocrinology Branch, United States Environment...

Vection Modulates Emotional Valence of Autobiographical Episodic Memories

ERIC Educational Resources Information Center

Seno, Takeharu; Kawabe, Takahiro; Ito, Hiroyuki; Sunaga, Shoji

2013-01-01

We examined whether illusory self-motion perception ("vection") induced by viewing upward and downward grating motion stimuli can alter the emotional valence of recollected autobiographical episodic memories. We found that participants recollected positive episodes more often while perceiving upward vection. However, when we tested a small moving…

Sounds Exaggerate Visual Shape

ERIC Educational Resources Information Center

Sweeny, Timothy D.; Guzman-Martinez, Emmanuel; Ortega, Laura; Grabowecky, Marcia; Suzuki, Satoru

2012-01-01

While perceiving speech, people see mouth shapes that are systematically associated with sounds. In particular, a vertically stretched mouth produces a /woo/ sound, whereas a horizontally stretched mouth produces a /wee/ sound. We demonstrate that hearing these speech sounds alters how we see aspect ratio, a basic visual feature that contributes…

Comparative transcriptomics involving greenbug and water-deficit stress responses in hard-red winter wheat

USDA-ARS?s Scientific Manuscript database

Sessile nature of plants necessitates them to perceive impending cues about biotic and abiotic stresses and alter their growth accordingly by eliciting appropriate defense signals. During the evolutionary progression, plants have developed sophisticated mechanisms to precisely identify the nature of...

The feasibility and utility of grocery receipt analyses for dietary assessment.

PubMed

Martin, Sarah Levin; Howell, Teresa; Duan, Yan; Walters, Michele

2006-03-30

To establish the feasibility and utility of a simple data collection methodology for dietary assessment. Using a cross-sectional design, trained data collectors approached adults (approximately 20 - 40 years of age) at local grocery stores and asked whether they would volunteer their grocery receipts and answer a few questions for a small stipend (dollar 1). The grocery data were divided into 3 categories: "fats, oils, and sweets," "processed foods," and "low-fat/low-calorie substitutions" as a percentage of the total food purchase price. The questions assessed the shopper's general eating habits (eg, fast-food consumption) and a few demographic characteristics and health aspects (eg, perception of body size). Statistical Analyses Performed. Descriptive and analytic analyses using non-parametric tests were conducted in SAS. Forty-eight receipts and questionnaires were collected. Nearly every respondent reported eating fast food at least once per month; 27% ate out once or twice a day. Frequency of fast-food consumption was positively related to perceived body size of the respondent (p = 0.02). Overall, 30% of the food purchase price was for fats, oils, sweets, 10% was for processed foods, and almost 6% was for low-fat/low-calorie substitutions. Households where no one was perceived to be overweight spent a smaller proportion of their food budget on fats, oils, and sweets than did households where at least one person was perceived to be overweight (p = 0.10); household where the spouse was not perceived to be overweight spent less on fats, oils, and sweets (p = 0.02) and more on low-fat/low-calorie substitutions (p = 0.09) than did households where the spouse was perceived to be overweight; and, respondents who perceived themselves to be overweight spent more on processed foods than did respondents who did not perceive themselves to be overweight (p = 0.06). This simple dietary assessment method, although global in nature, may be a useful indicator of dietary practices as evidenced by its association with perceived weight status.

Comparing Psychosocial Correlates of Condomless Anal Sex in HIV-Diagnosed and HIV-Nondiagnosed Men Who Have Sex with Men: A Series of Meta-Analyses of Studies from 1993-2013.

PubMed

Lacefield, Katharine; Negy, Charles; Schrader, Ronald M; Kuhlman, Christina

2015-09-01

Men who have sex with men (MSM) continue to be overrepresented in rates of incidence and prevalence of human immunodeficiency virus (HIV). Both HIV-diagnosed (HIV-D) and HIV-nondiagnosed (HIV-N) MSM report a variety of reasons for intentional and unintentional nonuse of condoms. Elucidating and comparing reasons for continued engagement in condomless anal sex specific to both HIV-D and HIV-N MSM likely is important to identifying effective prevention. This study employed meta-analytic methods to evaluate and compare correlates to condomless anal sex in both HIV-D and HIV-N MSM from primary studies from 1993 to February 2013. Of the 19 individual correlates assessed within the subgroup of HIV-D MSM, variables that achieved significant effect were alcohol, mind-altering substance use, sexual-enhancement medication, intentional condom nonuse, self-efficacy, attitudes toward condom use, social support, gay identity, compulsivity, trading sex, and number of sex partners. Those that were statistically non-significant were intention to use a condom, perceived risk, perceived norms, perceived responsibility, HIV medical management, treatment optimism, mental health, and setting. Of the 12 correlates assessed within the subgroup of HIV-N MSM, variables that achieved significant effect were alcohol, mind-altering substance use, intentional condom nonuse, attitudes toward condom use, perceived risk, and setting. Those observed as statistically non-significant were perceived norms, social support, gay identity, mental health, trading sex, and number of sex partners. Study results have clinical implications that may guide future prevention research and practice by highlighting risk variables shared between HIV-N and HIV-D MSM, as well as variables observed to be unique to each group that may warrant more tailored intervention. Further investigation is recommended to elucidate the relationships among these variables such that optimal intervention can be determined.

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

PubMed

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

2012-02-01

To assess Australian consumers' perception of portion size of fast-food items and their ability to estimate energy content. Cross-sectional computer-based survey. Australia. Fast-food consumers (168 male, 324 female) were asked to recall the items eaten at the most recent visit to a fast-food restaurant, rate the prospective satiety and estimate the energy content of seven fast-food or 'standard' meals relative to a 9000 kJ Guideline Daily Amount. Nine dietitians also completed the energy estimation task. Ratings of prospective satiety generally aligned with the actual size of the meals and indicated that consumers perceived all meals to provide an adequate amount of food, although this differed by gender. The magnitude of the error in energy estimation by consumers was three to ten times that of the dietitians. In both males and females, the average error in energy estimation for the fast-food meals (females: mean 3911 (sd 1998) kJ; males: mean 3382 (sd 1957) kJ) was significantly (P < 0·001) larger than for the standard meals (females: mean 2607 (sd 1623) kJ; males: mean 2754 (sd 1652) kJ). In women, error in energy estimation for fast-food items predicted actual energy intake from fast-food items (β = 0·16, P < 0·01). Knowledge of the energy content of standard and fast-food meals in fast-food consumers in Australia is poor. Awareness of dietary energy should be a focus of health promotion if nutrition information, in its current format, is going to alter behaviour.

Perceived racial discrimination, but not mistrust of medical researchers, predicts the heat pain tolerance of African Americans with symptomatic knee osteoarthritis.

PubMed

Goodin, Burel R; Pham, Quyen T; Glover, Toni L; Sotolongo, Adriana; King, Christopher D; Sibille, Kimberly T; Herbert, Matthew S; Cruz-Almeida, Yenisel; Sanden, Shelley H; Staud, Roland; Redden, David T; Bradley, Laurence A; Fillingim, Roger B

2013-11-01

Studies have shown that perceived racial discrimination is a significant predictor of clinical pain severity among African Americans. It remains unknown whether perceived racial discrimination also alters the nociceptive processing of painful stimuli, which, in turn, could influence clinical pain severity. This study examined associations between perceived racial discrimination and responses to noxious thermal stimuli among African Americans and non-Hispanic Whites. Mistrust of medical researchers was also assessed given its potential to affect responses to the noxious stimuli. One-hundred and 30 (52% African American, 48% non-Hispanic White) community-dwelling older adults with symptomatic knee osteoarthritis completed two study sessions. In session one, individuals provided demographic, socioeconomic, physical and mental health information. They completed questionnaires related to perceived lifetime frequency of racial discrimination and mistrust of medical researchers. In session two, individuals underwent a series of controlled thermal stimulation procedures to assess heat pain sensitivity, particularly heat pain tolerance. African Americans were more sensitive to heat pain and reported greater perceived racial discrimination as well as greater mistrust of medical researchers compared with non-Hispanic Whites. Greater perceived racial discrimination significantly predicted lower heat pain tolerance for African Americans but not non-Hispanic Whites. Mistrust of medical researchers did not significantly predict heat pain tolerance for either racial group. These results lend support to the idea that perceived racial discrimination may influence the clinical pain severity of African Americans via the nociceptive processing of painful stimuli.

Components of family history associated with women's disease perceptions for cancer: a report from the Family Healthware™ Impact Trial.

PubMed

Rubinstein, Wendy S; O'neill, Suzanne M; Rothrock, Nan; Starzyk, Erin J; Beaumont, Jennifer L; Acheson, Louise S; Wang, Catharine; Gramling, Robert; Galliher, James M; Ruffin, Mack T

2011-01-01

To determine the specific components of family history and personal characteristics related to disease perceptions about breast, colon, and ovarian cancers. Baseline, cross-sectional data on 2,505 healthy women aged 35-65 years enrolled from 41 primary care practices in the cluster-randomized Family Healthware™ Impact Trial, assessed for detailed family history and perceived risk, perceived severity, worry, and perceived control over getting six common diseases including breast, colon, and ovarian cancers. Participants provided family history information on 41,841 total relatives. We found evidence of underreporting of paternal family history and lower perceived breast cancer risk with cancer in the paternal versus maternal lineage. We observed cancer-specific perceived risks and worry for individual family history elements and also found novel "spillover" effects where a family history of one cancer was associated with altered disease perceptions of another. Having a mother with early-onset breast or ovarian cancer was strongly associated with perceived risk of breast cancer. Age, parenthood, and affected lineage were associated with disease perceptions and ran counter to empiric risks. Understanding patients' formulation of risk for multiple diseases is important for public health initiatives that seek to inform risk appraisal, influence disease perceptions, or match preventive interventions to existing risk perceptions.

Interocular induction of illusory size perception.

PubMed

Song, Chen; Schwarzkopf, D Samuel; Rees, Geraint

2011-03-11

The perceived size of objects not only depends on their physical size but also on the surroundings in which they appear. For example, an object surrounded by small items looks larger than a physically identical object surrounded by big items (Ebbinghaus illusion), and a physically identical but distant object looks larger than an object that appears closer in space (Ponzo illusion). Activity in human primary visual cortex (V1) reflects the perceived rather than the physical size of objects, indicating an involvement of V1 in illusory size perception. Here we investigate the role of eye-specific signals in two common size illusions in order to provide further information about the mechanisms underlying illusory size perception. We devised stimuli so that an object and its spatial context associated with illusory size perception could be presented together to one eye or separately to two eyes. We found that the Ponzo illusion had an equivalent magnitude whether the objects and contexts were presented to the same or different eyes, indicating that it may be largely mediated by binocular neurons. In contrast, the Ebbinghaus illusion became much weaker when objects and their contexts were presented to different eyes, indicating important contributions to the illusion from monocular neurons early in the visual pathway. Our findings show that two well-known size illusions - the Ponzo illusion and the Ebbinghaus illusion - are mediated by different neuronal populations, and suggest that the underlying neural mechanisms associated with illusory size perception differ and can be dependent on monocular channels in the early visual pathway.

Taking a Hands-On Approach: Apparent Grasping Ability Scales the Perception of Object Size

ERIC Educational Resources Information Center

Linkenauger, Sally A.; Witt, Jessica K.; Proffitt, Dennis R.

2011-01-01

We examined whether the apparent size of an object is scaled to the morphology of the relevant body part with which one intends to act on it. To be specific, we tested if the visually perceived size of graspable objects is scaled to the extent of apparent grasping ability for the individual. Previous research has shown that right-handed…

Human-resource professionals' perceptions of organizational politics as a function of experience, organizational size, and perceived independence.

PubMed

Conner, Deondra S

2006-12-01

The author examined human-resource professionals' occupation-related and general work experience, socialization from participation in professional activities, organizational size, and perceived independence as predictors of perceptions of organizational politics (POPS). Results varied with the author's use of the overall POPS scale (K. M. Kacmar & G. R. Ferris, 1991) vs. a more specific subscale that measured perceptions related to such issues as pay- and promotion-related politics. It was most notable that work experience appeared to have an inverse relationship with POPS among human-resource professionals in the area of pay and promotions. The author discussed results in relation to the implications and directions for future research.

Thinking big: the effect of sexually objectifying music videos on bodily self-perception in young women.

PubMed

Mischner, Isabelle H S; van Schie, Hein T; Wigboldus, Daniël H J; van Baaren, Rick B; Engels, Rutger C M E

2013-01-01

The present study investigated the effect of sexually objectifying music video exposure on young women's implicit bodily self-perception and the moderating role of self-esteem. Fifty-six college women of normal weight were either exposed to three sexually objectifying music videos or three neutral music videos. Perceived and ideal body size were measured both before and after video exposure, using horizontally stretched and compressed photographs of the participant's own body in swimming garment. As expected, only women low (but not high) in self-esteem were negatively affected by the sexually objectifying content of the music videos: they perceived themselves as bigger and showed an increased discrepancy between their perceived and ideal body size after video exposure. The neutral music videos did not influence women's bodily self-perceptions. These findings suggest that body image is a flexible construct, and that high self-esteem can protect women against the adverse effects of sexually objectifying media. Copyright © 2012 Elsevier Ltd. All rights reserved.

Does Screen Size Matter for Smartphones? Utilitarian and Hedonic Effects of Screen Size on Smartphone Adoption

PubMed Central

Kim, Ki Joon

2014-01-01

Abstract This study explores the psychological effects of screen size on smartphone adoption by proposing an extended Technology Acceptance Model (TAM) that integrates an empirical comparison between large and small screens with perceived control, affective quality, and the original TAM constructs. A structural equation modeling analysis was conducted on data collected from a between-subjects experiment (N=130) in which users performed a web-based task on a smartphone with either a large (5.3 inches) or a small (3.7 inches) screen. Results show that a large screen, compared to a small screen, is likely to lead to higher smartphone adoption by simultaneously promoting both the utilitarian and hedonic qualities of smartphones, which in turn positively influence perceived ease of use of—and attitude toward—the device respectively. Implications and directions for future research are discussed. PMID:24694112

Does screen size matter for smartphones? Utilitarian and hedonic effects of screen size on smartphone adoption.

PubMed

Kim, Ki Joon; Sundar, S Shyam

2014-07-01

This study explores the psychological effects of screen size on smartphone adoption by proposing an extended Technology Acceptance Model (TAM) that integrates an empirical comparison between large and small screens with perceived control, affective quality, and the original TAM constructs. A structural equation modeling analysis was conducted on data collected from a between-subjects experiment (N=130) in which users performed a web-based task on a smartphone with either a large (5.3 inches) or a small (3.7 inches) screen. Results show that a large screen, compared to a small screen, is likely to lead to higher smartphone adoption by simultaneously promoting both the utilitarian and hedonic qualities of smartphones, which in turn positively influence perceived ease of use of-and attitude toward-the device respectively. Implications and directions for future research are discussed.

Perceived causality, force, and resistance in the absence of launching.

PubMed

Hubbard, Timothy L; Ruppel, Susan E

2017-04-01

In the launching effect, a moving object (the launcher) contacts a stationary object (the target), and upon contact, the launcher stops and the target begins moving in the same direction and at the same or slower velocity as previous launcher motion (Michotte, 1946/1963). In the study reported here, participants viewed a modified launching effect display in which the launcher stopped before or at the moment of contact and the target remained stationary. Participants rated perceived causality, perceived force, and perceived resistance of the launcher on the target or the target on the launcher. For launchers and for targets, increases in the size of the spatial gap between the final location of the launcher and the location of the target decreased ratings of perceived causality and ratings of perceived force and increased ratings of perceived resistance. Perceived causality, perceived force, and perceived resistance exhibited gradients or fields extending from the launcher and from the target and were not dependent upon contact of the launcher and target. Causal asymmetries and force asymmetries reported in previous studies did not occur, and this suggests that such asymmetries might be limited to typical launching effect stimuli. Deviations from Newton's laws of motion are noted, and the existence of separate radii of action extending from the launcher and from the target is suggested.

Welcome to Wonderland: The Influence of the Size and Shape of a Virtual Hand On the Perceived Size and Shape of Virtual Objects

PubMed Central

Linkenauger, Sally A.; Leyrer, Markus; Bülthoff, Heinrich H.; Mohler, Betty J.

2013-01-01

The notion of body-based scaling suggests that our body and its action capabilities are used to scale the spatial layout of the environment. Here we present four studies supporting this perspective by showing that the hand acts as a metric which individuals use to scale the apparent sizes of objects in the environment. However to test this, one must be able to manipulate the size and/or dimensions of the perceiver’s hand which is difficult in the real world due to impliability of hand dimensions. To overcome this limitation, we used virtual reality to manipulate dimensions of participants’ fully-tracked, virtual hands to investigate its influence on the perceived size and shape of virtual objects. In a series of experiments, using several measures, we show that individuals’ estimations of the sizes of virtual objects differ depending on the size of their virtual hand in the direction consistent with the body-based scaling hypothesis. Additionally, we found that these effects were specific to participants’ virtual hands rather than another avatar’s hands or a salient familiar-sized object. While these studies provide support for a body-based approach to the scaling of the spatial layout, they also demonstrate the influence of virtual bodies on perception of virtual environments. PMID:23874681

The influence of craniofacial to standing height proportion on perceived attractiveness.

PubMed

Naini, F B; Cobourne, M T; McDonald, F; Donaldson, A N A

2008-10-01

An idealised male image, based on Vitruvian Man, was created. The craniofacial height was altered from a proportion of 1/6 to 1/10 of standing height, creating 10 images shown in random order to 89 observers (74 lay people; 15 clinicians), who ranked the images from the most to the least attractive. The main outcome was the preference ranks of image attractiveness given by the observers. Linear regressions were used to assess what influences the choice for the most and the least attractive images, followed by a multivariate rank ordinal logistic regression to test the influence of age, gender, ethnicity and professional status of the observer. A craniofacial height to standing height proportion of 1/7.5 was perceived as the most attractive (36%), followed by a proportion of 1/8 (26%). The images chosen as most attractive by more than 10% of observers had a mean proportion of 1/7.8(min=1/7; max=1/8.5). The images perceived as most unattractive had a proportion of 1/6 and 1/10. The choice of images was not influenced by the age, gender, ethnicity or professional status of the observers. The ideal craniofacial height to standing height proportion is in the range 1/7 to 1/8.5. This finding should be considered when planning treatment to alter craniofacial or facial height.

Predictors of physical performance and functional ability in people 50+ with and without fibromyalgia.

PubMed

Jones, C Jessie; Rutledge, Dana N; Aquino, Jordan

2010-07-01

The purposes of this study were to determine whether people with and without fibromyalgia (FM) age 50 yr and above showed differences in physical performance and perceived functional ability and to determine whether age, gender, depression, and physical activity level altered the impact of FM status on these factors. Dependent variables included perceived function and 6 performance measures (multidimensional balance, aerobic endurance, overall functional mobility, lower body strength, and gait velocity-normal or fast). Independent (predictor) variables were FM status, age, gender, depression, and physical activity level. Results indicated significant differences between adults with and without FM on all physical-performance measures and perceived function. Linear-regression models showed that the contribution of significant predictors was in expected directions. All regression models were significant, accounting for 16-65% of variance in the dependent variables.

The Affective Gatekeeper: A Synthesis of Perspectives on Creativity.

ERIC Educational Resources Information Center

Bagley, Dan S., III

1979-01-01

The article presents research reports on the nature of creativity, including such elements as its characteristics; the function of the affective gatekeeper (which filters the "reality" perceived by each individual); the constructs of perception; and the functions of role playing, altered states of consciousness, and fantasy. (PHR)

Interpreting the Value of Ecosystem Services in a Great Lakes Estuary from the Behavior of Individuals and Communities

EPA Science Inventory

Fundamentally, economists study human behavior. Financial and political investments are justified in terms of the real, perceived, or potential value of benefits. Unlike economic systems, investments in and benefits from ecosystems are difficult to monetize. We are applying alter...

Brief Report: Altered Horizontal Binding of Single Dots to Coherent Motion in Autism

ERIC Educational Resources Information Center

David, Nicole; Rose, Michael; Schneider, Till R.; Vogeley, Kai; Engel, Andreas K.

2010-01-01

Individuals with autism often show a fragmented way of perceiving their environment, suggesting a disorder of information integration, possibly due to disrupted communication between brain areas. We investigated thirteen individuals with high-functioning autism (HFA) and thirteen healthy controls using the metastable motion quartet, a stimulus…

Feelings of Control: Contingency Determines Experience of Action

ERIC Educational Resources Information Center

Moore, James W.; Lagnado, David; Deal, Darvany C.; Haggard, Patrick

2009-01-01

The experience of causation is a pervasive product of the human mind. Moreover, the experience of causing an event alters subjective time: actions are perceived as temporally shifted towards their effects [Haggard, P., Clark, S., & Kalogeras, J. (2002). Voluntary action and conscious awareness. "Nature Neuroscience," 5(4), 382-385]. This temporal…

Ventilation and Speech Characteristics during Submaximal Aerobic Exercise

ERIC Educational Resources Information Center

Baker, Susan E.; Hipp, Jenny; Alessio, Helaine

2008-01-01

Purpose: This study examined alterations in ventilation and speech characteristics as well as perceived dyspnea during submaximal aerobic exercise tasks. Method: Twelve healthy participants completed aerobic exercise-only and simultaneous speaking and aerobic exercise tasks at 50% and 75% of their maximum oxygen consumption (VO[subscript 2] max).…

Cultural Complicities: Elitism, Heteronormativity and Violence in the Education Marketplace

ERIC Educational Resources Information Center

Saltmarsh, Sue

2007-01-01

Educational discourse in Australia has been dramatically altered in recent decades as neoliberal choice policies favouring an increasingly marketized, tiered educational landscape have witnessed a burgeoning of private sector schooling. In this climate, many perceive private sector schooling as providing moral, social and academic benefits beyond…

Disabling Spatialities and the Regulation of a Visible Secret.

ERIC Educational Resources Information Center

Hawkesworth, Marian

2001-01-01

Participants in this study testify that acne alterations to the skin often bring about changes in spatial practices or body movements on account of society's aesthetic prejudices regarding facial disfigurement. Examines the urban geographies of people distinguished by their perceived facial differences. Explains that problems of exclusion arise…

Effects of eccentricity on color contrast.

PubMed

Vanston, John E; Crognale, Michael A

2018-04-01

Using near-threshold stimuli, human color sensitivity has been shown to decrease across the visual field, likely due in part to physiological differences between the fovea and periphery. It remains unclear to what extent this holds true for suprathreshold stimuli. The current study used suprathreshold contrast matching to examine how perceived contrast varies with eccentricity along the cardinal axes in a cone-opponent space. Our data show that, despite increasing stimulus size in the periphery, the LM axis stimuli were still perceived as reduced in contrast, whereas the S axis perceived contrast was observed to increase with eccentricity.

Controlling the perceived distance of an auditory object by manipulation of loudspeaker directivity.

PubMed

Laitinen, Mikko-Ville; Politis, Archontis; Huhtakallio, Ilkka; Pulkki, Ville

2015-06-01

This work presents a method to control the perceived distance of an auditory object by changing the directivity pattern of a loudspeaker and consequently the direct-to-reverberant ratio at the listening spot. Control of the directivity pattern is achieved by beamforming using a compact multi-driver loudspeaker unit. A small-sized cubic array consisting of six drivers is assembled, and per driver beamforming filters are derived from directional measurements of the array. The proposed method is evaluated using formal listening tests. The results show that the perceived distance can be controlled effectively by directivity pattern modification.

Time counts: future time perspective, goals, and social relationships.

PubMed

Lang, Frieder R; Carstensen, Laura L

2002-03-01

On the basis of postulates derived from socioemotional selectivity theory, the authors explored the extent to which future time perspective (FTP) is related to social motivation, and to the composition and perceived quality of personal networks. Four hundred eighty German participants with ages ranging from 20 to 90 years took part in the study. In 2 card-sort tasks, participants indicated their partner preference and goal priority. Participants also completed questionnaires on personal networks and social satisfaction. Older people, as a group, perceived their future time as more limited than younger people. Individuals who perceived future time as being limited prioritized emotionally meaningful goals (e.g., generativity, emotion regulation), whereas individuals who perceived their futures as open-ended prioritized instrumental or knowledge-related goals. Priority of goal domains was found to be differently associated with the size, composition, and perceived quality of personal networks depending on FTP. Prioritizing emotion-regulatory goals was associated with greater social satisfaction and less perceived strain with others when participants perceived their future as limited. Findings underscore the importance of FTP in the self-regulation of social relationships and the subjective experience associated with them.

Analysis of perceived risk among construction workers: a cross-cultural study and reflection on the Hofstede model.

PubMed

Martinez-Fiestas, Myriam; Rodríguez-Garzón, Ignacio; Delgado-Padial, Antonio; Lucas-Ruiz, Valeriano

2017-09-01

This article presents a cross-cultural study on perceived risk in the construction industry. Worker samples from three different countries were studied: Spain, Peru and Nicaragua. The main goal was to explain how construction workers perceive their occupational hazard and to analyze how this is related to their national culture. The model used to measure perceived risk was the psychometric paradigm. The results show three very similar profiles, indicating that risk perception is independent of nationality. A cultural analysis was conducted using the Hofstede model. The results of this analysis and the relation to perceived risk showed that risk perception in construction is independent of national culture. Finally, a multiple lineal regression analysis was conducted to determine what qualitative attributes could predict the global quantitative size of risk perception. All of the findings have important implications regarding the management of safety in the workplace.

Kindergarten Children's Perception of Animals Focusing on the Look and Fear of Animals

ERIC Educational Resources Information Center

Kubiatko, Milan

2012-01-01

The study is focusing on the finding out the children's perceiving of animals from the view of look and fear. The additional aims were to find out the influence of gender and age on the perceiving of animals from the view of look and fear. The sample size was created by the 27 Czech kindergarten children from two kindergartens. The number of 5…

Social Network Characteristics, Social Support, and Cigarette Smoking among Asian/Pacific Islander Young Adults

PubMed Central

Pokhrel, Pallav; Fagan, Pebbles; Cassel, Kevin; Trinidad, Dennis R.; Kaholokula, Joseph Keawe‘aimoku; Herzog, Thaddeus A.

2016-01-01

Cigarette smoking may be one of the factors contributing to the high levels of cancer-related mortality experienced by certain Asian/Pacific Islander (A/PI) subgroups (e.g., Native Hawaiian). Given the collectivist cultural orientation attributed to A/PI groups, social strategies are recommended for substance abuse or smoking cessation treatment among A/PI. However, research examining how social network characteristics and social support relate to smoking across A/PI subgroups has been lacking. This study investigated the associations between social network characteristics (e.g., size, composition), perceived social support, and recent cigarette use across Native Hawaiian, Filipino, and East Asian (e.g., Japanese, Chinese) young adults (18–35 year old). Cross-sectional, self-report data were collected from N = 435 participants (M age = 25.6, SD = 8.3; 61% women). Ethnic differences were found in a number of pathways linking social network characteristics, perceived social support, and cigarette smoking. Larger network size was strongly associated with higher perceived social support and lower recent cigarette smoking among Native Hawaiians but not Filipinos or East Asians. Higher perceived social support was associated with lower recent smoking among East Asians and Filipinos but not Native Hawaiians. Implications are discussed with regard to smoking prevention and cessation among A/PI. PMID:27297612

Using body size to predict perceptual range

Treesearch

Stephen G. Mech; Patrick A. Zollner

2002-01-01

We examined the relationship between body size and perceptual range (the distance at which an animal can perceive landscape elements) for a group of forest-dwelling rodents. We used previously published data on orientation ability at various distances for three sciurid species (gray squirrel, fox squirrel and chipmunk) and one murid species (white-footed mouse) to...

A Matter of Size: Flipping Library Instruction in Various Engineering Classrooms

ERIC Educational Resources Information Center

Maddison, Tasha

2015-01-01

This case study explores the use of flipped teaching in three different undergraduate engineering courses, discussing the advantages and disadvantages of class size and how it affects the delivery of information literacy instruction as observed through student engagement and the perceived helpfulness of the instruction. A flipped classroom was…

The spiral aftereffect : III, Some effects of perceived size, retinal size, and retinal speed on the duration of illusory motion.

DOT National Transportation Integrated Search

1971-07-01

Many safety problems encountered in aviation have been attributed to visual illusions. One of the various types of visual illusions, that of apparent motion, includes as an aftereffect the apparent reversed motion of an object after it ceases real mo...

Class Size: Teachers' Perspectives

ERIC Educational Resources Information Center

Watson, Kevin; Handal, Boris; Maher, Marguerite

2016-01-01

A consistent body of research shows that large classes have been perceived by teachers as an obstacle to deliver quality teaching. This large-scale study sought to investigate further those differential effects by asking 1,119 teachers from 321 K-12 schools in New South Wales (Australia) their perceptions of ideal class size for a variety of…

Characterization of an air jet haptic lump display.

PubMed

Bianchi, Matteo; Gwilliam, James C; Degirmenci, Alperen; Okamura, Allison M

2011-01-01

During manual palpation, clinicians rely on distributed tactile information to identify and localize hard lumps embedded in soft tissue. The development of tactile feedback systems to enhance palpation using robot-assisted minimally invasive surgery (RMIS) systems is challenging due to size and weight constraints, motivating a pneumatic actuation strategy. Recently, an air jet approach has been proposed for generating a lump percept. We use this technique to direct a thin stream of air through an aperture directly on the finger pad, which indents the skin in a hemispherical manner, producing a compelling lump percept. We hypothesize that the perceived parameters of the lump (e.g. size and stiffness) can be controlled by jointly adjusting air pressure and the aperture size through which air escapes. In this work, we investigate how these control variables interact to affect perceived pressure on the finger pad. First, we used a capacitive tactile sensor array to measure the effect of aperture size on output pressure, and found that peak output pressure increases with aperture size. Second, we performed a psychophysical experiment for each aperture size to determine the just noticeable difference (JND) of air pressure on the finger pad. Subject-averaged pressure JND values ranged from 19.4-24.7 kPa, with no statistical differences observed between aperture sizes. The aperture-pressure relationship and the pressure JND values will be fundamental for future display control.

Perceived racial discrimination, but not mistrust of medical researchers, predicts the heat pain tolerance of African Americans with symptomatic knee osteoarthritis

PubMed Central

Pham, Quyen T.; Glover, Toni L.; Sotolongo, Adriana; King, Christopher D.; Sibille, Kimberly T.; Herbert, Matthew S.; Cruz-Almeida, Yenisel; Sanden, Shelley H.; Staud, Roland; Redden, David T.; Bradley, Laurence A.; Fillingim, Roger B.

2014-01-01

Objective Studies have shown that perceived racial discrimination is a significant predictor of clinical pain severity among African Americans. It remains unknown whether perceived racial discrimination also alters the nociceptive processing of painful stimuli, which, in turn, could influence clinical pain severity. This study examined associations between perceived racial discrimination and responses to noxious thermal stimuli among African Americans and non-Hispanic whites. Mistrust of medical researchers was also assessed given its potential to affect responses to the noxious stimuli. Method One hundred and thirty (52% African American, 48% non-Hispanic white) community-dwelling older adults with symptomatic knee osteoarthritis completed two study sessions. In session one, individuals provided demographic, socioeconomic, physical and mental health information. They completed questionnaires related to perceived lifetime frequency of racial discrimination and mistrust of medical researchers. In session two, individuals underwent a series of controlled thermal stimulation procedures to assess heat pain sensitivity, particularly heat pain tolerance. Results African Americans were more sensitive to heat pain and reported greater perceived racial discrimination as well as greater mistrust of medical researchers compared to non-Hispanic whites. Greater perceived racial discrimination significantly predicted lower heat pain tolerance for African Americans but not non-Hispanic whites. Mistrust of medical researchers did not significantly predict heat pain tolerance for either racial group Conclusion These results lend support to the idea that perceived racial discrimination may influence the clinical pain severity of African Americans via the nociceptive processing of painful stimuli. PMID:24219416

Muscle fiber type proportion and size is not altered in mcardle disease.

PubMed

Henning, Franclo; Cunninghame, Carol Anne; Martín, Miguel Angel; Rubio, Juan Carlos; Arenas, Joaquín; Lucia, Alejandro; HernáNdez-Laín, Aurelio; Kohn, Tertius Abraham

2017-06-01

McArdle disease is a metabolic myopathy that presents with exercise intolerance and episodic rhabdomyolysis. Excessive muscle recruitment has also been shown to be present during strenuous exercise, suggesting decreased power output. These findings could potentially be explained by either impaired contractility, decreased fiber size, or altered fiber type proportion. However, there is a paucity of data on the morphological features seen on muscle histology. We examined muscle biopsies of patients with McArdle disease from a Spanish cohort and compared the findings with healthy controls. We found no significant difference in the fiber type proportion or mean fiber size between McArdle patients and controls in the biceps brachii or vastus lateralis muscles. No alterations in muscle fiber type proportion or size were found on muscle histology of patients with McArdle disease. Future research should focus on assessment of muscle fiber contractility to investigate the functional impairment. Muscle Nerve 55: 916-918, 2017. © 2016 Wiley Periodicals, Inc.

Nanoparticle distribution during systemic inflammation is size-dependent and organ-specific

NASA Astrophysics Data System (ADS)

Chen, K.-H.; Lundy, D. J.; Toh, E. K.-W.; Chen, C.-H.; Shih, C.; Chen, P.; Chang, H.-C.; Lai, J. J.; Stayton, P. S.; Hoffman, A. S.; Hsieh, P. C.-H.

2015-09-01

This study comprehensively investigates the changing biodistribution of fluorescent-labelled polystyrene latex bead nanoparticles in a mouse model of inflammation. Since inflammation alters systemic circulatory properties, increases vessel permeability and modulates the immune system, we theorised that systemic inflammation would alter nanoparticle distribution within the body. This has implications for prospective nanocarrier-based therapies targeting inflammatory diseases. Low dose lipopolysaccharide (LPS), a bacterial endotoxin, was used to induce an inflammatory response, and 20 nm, 100 nm or 500 nm polystyrene nanoparticles were administered after 16 hours. HPLC analysis was used to accurately quantify nanoparticle retention by each vital organ, and tissue sections revealed the precise locations of nanoparticle deposition within key tissues. During inflammation, nanoparticles of all sizes redistributed, particularly to the marginal zones of the spleen. We found that LPS-induced inflammation induces splenic macrophage polarisation and alters leukocyte uptake of nanoparticles, with size-dependent effects. In addition, spleen vasculature becomes significantly more permeable following LPS treatment. We conclude that systemic inflammation affects nanoparticle distribution by multiple mechanisms, in a size dependent manner.This study comprehensively investigates the changing biodistribution of fluorescent-labelled polystyrene latex bead nanoparticles in a mouse model of inflammation. Since inflammation alters systemic circulatory properties, increases vessel permeability and modulates the immune system, we theorised that systemic inflammation would alter nanoparticle distribution within the body. This has implications for prospective nanocarrier-based therapies targeting inflammatory diseases. Low dose lipopolysaccharide (LPS), a bacterial endotoxin, was used to induce an inflammatory response, and 20 nm, 100 nm or 500 nm polystyrene nanoparticles were administered after 16 hours. HPLC analysis was used to accurately quantify nanoparticle retention by each vital organ, and tissue sections revealed the precise locations of nanoparticle deposition within key tissues. During inflammation, nanoparticles of all sizes redistributed, particularly to the marginal zones of the spleen. We found that LPS-induced inflammation induces splenic macrophage polarisation and alters leukocyte uptake of nanoparticles, with size-dependent effects. In addition, spleen vasculature becomes significantly more permeable following LPS treatment. We conclude that systemic inflammation affects nanoparticle distribution by multiple mechanisms, in a size dependent manner. Electronic supplementary information (ESI) available: IF images of brain, heart, low magnification images of spleen, mouse heart rate and blood pressure post-LPS. See DOI: 10.1039/c5nr03626g

Interocular induction of illusory size perception

PubMed Central

2011-01-01

Background The perceived size of objects not only depends on their physical size but also on the surroundings in which they appear. For example, an object surrounded by small items looks larger than a physically identical object surrounded by big items (Ebbinghaus illusion), and a physically identical but distant object looks larger than an object that appears closer in space (Ponzo illusion). Activity in human primary visual cortex (V1) reflects the perceived rather than the physical size of objects, indicating an involvement of V1 in illusory size perception. Here we investigate the role of eye-specific signals in two common size illusions in order to provide further information about the mechanisms underlying illusory size perception. Results We devised stimuli so that an object and its spatial context associated with illusory size perception could be presented together to one eye or separately to two eyes. We found that the Ponzo illusion had an equivalent magnitude whether the objects and contexts were presented to the same or different eyes, indicating that it may be largely mediated by binocular neurons. In contrast, the Ebbinghaus illusion became much weaker when objects and their contexts were presented to different eyes, indicating important contributions to the illusion from monocular neurons early in the visual pathway. Conclusions Our findings show that two well-known size illusions - the Ponzo illusion and the Ebbinghaus illusion - are mediated by different neuronal populations, and suggest that the underlying neural mechanisms associated with illusory size perception differ and can be dependent on monocular channels in the early visual pathway. PMID:21396093

Does body size affect a bird's sensitivity to patch size and landscape structure?

USGS Publications Warehouse

Winter, Maiken; Johnson, Douglas H.; Shaffer, Jill A.

2006-01-01

Larger birds are generally more strongly affected by habitat loss and fragmentation than are smaller ones because they require more resources and thus larger habitat patches. Consequently, conservation actions often favor the creation or protection of larger over smaller patches. However, in grassland systems the boundaries between a patch and the surrounding landscape, and thus the perceived size of a patch, can be indistinct. We investigated whether eight grassland bird species with different body sizes perceived variation in patch size and landscape structure in a consistent manner. Data were collected from surveys conducted in 44 patches of northern tallgrass prairie during 1998–2001. The response to patch size was very similar among species regardless of body size (density was little affected by patch size), except in the Greater Prairie-Chicken (Tympanuchus cupido), which showed a threshold effect and was not found in patches smaller than 140 ha. In landscapes containing 0%–30% woody vegetation, smaller species responded more negatively to increases in the percentage of woody vegetation than larger species, but above an apparent threshold of 30%, larger species were not detected. Further analyses revealed that the observed variation in responses to patch size and landscape structure among species was not solely due to body size per se, but to other differences among species. These results indicate that a stringent application of concepts requiring larger habitat patches for larger species appears to limit the number of grassland habitats that can be protected and may not always be the most effective conservation strategy.

Variation in home range size of red foxes Vulpes vulpes along a gradient of productivity and human landscape alteration

PubMed Central

2017-01-01

Home range size is a fundamental concept for understanding animal dispersion and ecological needs, and it is one of the most commonly reported ecological attributes of free-ranging mammals. Previous studies indicate that red foxes Vulpes vulpes display great variability in home range size. Yet, there has been little consensus regarding the reasons why home range sizes of red foxes vary so extensively. In this study, we examine possible causes of variation in red fox home range sizes using data from 52 GPS collared red foxes from four study areas representing a gradient of landscape productivity and human landscape alteration in Norway and Sweden. Using 90% Local Convex Hull home range estimates, we examined how red fox home range size varied in relation to latitude, elevation, vegetation zone, proportion of agricultural land and human settlement within a home range, and sex and age. We found considerable variation in red fox home range sizes, ranging between 0.95 km2 to 44 km2 (LoCoH 90%) and 2.4 km2 to 358 km2 (MCP 100%). Elevation, proportion of agricultural land and sex accounted for 50% of the variation in home range size found amongst foxes, with elevation having the strongest effect. Red foxes residing in more productive landscapes (those in more southern vegetation zones), had home ranges approximately four times smaller than the home ranges of foxes in the northern boreal vegetation zone. Our results indicate that home range size was influenced by a productivity gradient at both the landscape (latitude) and the local (elevation) scale. The influence of the proportion of agriculture land on home range size of foxes illustrates how human landscape alteration can affect the space use and distribution of red foxes. Further, the variation in home range size found in this study demonstrates the plasticity of red foxes to respond to changing human landscape alteration as well as changes in landscape productivity, which may be contributing to red fox population increases and northern range expansions. PMID:28384313

Altering the Trajectory of the Self-Fulfilling Prophecy: Asset-Based Pedagogy and Classroom Dynamics

ERIC Educational Resources Information Center

López, Francesca A.

2017-01-01

Prior research has contributed to our understanding about the ways teachers communicate their expectations to students, how students perceive differential teacher behaviors, and their effect on students' own perceptions of ability and achievement. Despite more than half a century of this work, historically marginalized students continue to be…

Effect of Sex on Perceived Support and Burnout in University Students

ERIC Educational Resources Information Center

Weckwerth, Amanda C.; Flynn, Deborah M.

2006-01-01

Sex differences in the experience of social support and frequency of burnout were examined in university students from a small Northern Ontario University. An altered version of the Maslach Burnout Inventory Human Services Survey (MBI-HSS) (Maslach & Jackson, 1996) termed the AMBI-HSS, and the Social Provisions Scale (SPS) (Cutrona &…

Action Alters Object Identification: Wielding a Gun Increases the Bias to See Guns

ERIC Educational Resources Information Center

Witt, Jessica K.; Brockmole, James R.

2012-01-01

Stereotypes, expectations, and emotions influence an observer's ability to detect and categorize objects as guns. In light of recent work in action-perception interactions, however, there is another unexplored factor that may be critical: The action choices available to the perceiver. In five experiments, participants determined whether another…

[Dealing with the body through cosmetic surgery].

PubMed

Mateu, Jacques; Tournier, Sylvie

2011-06-01

Plastic surgery is reconstructive or cosmetic. It alters the appearance of a body which a patient is unable to live with, an unconventional or badly perceived body, one of the causes of malaise. After the operation, the patient must be supported without judgement in coming to terms with his or her new body image.

A Proactive Model to Control Reactive Behaviors

ERIC Educational Resources Information Center

Dehnad, Vida

2017-01-01

Adaptation to change is not an easy process and sometimes does not happen at all. When people perceive that their freedom is going to be altered due to an unwanted change, they outwardly exhibit some symptomatic reactive behaviors such as inertia, resistance, skepticism, and aggression. No matter how intense people's reactance is, only a few of…

The Experience of Children Living with Sensory Processing Disorder

ERIC Educational Resources Information Center

Scotch, Melissa Dawn

2017-01-01

Sensory processing disorder (SPD) is a neurological condition that alters the way an individual perceives sensory information. Although the condition has been studied for more than 40 years, SPD remains a difficult condition to diagnose, treat, and live with because it affects individuals uniquely, and the symptoms can change from childhood to…

Stress habituation and alterations in perceived stress predict BMI percentile changes across a school year

USDA-ARS?s Scientific Manuscript database

Adolescents experience stressful situations at a high rate during school. Indeed, school is the most common source of stress for teens. This high rate of stress may promote increases in adiposity during a developmental period important for establishing the adult physique. Adiposity gains may be th...

Chilling-induced tomato flavor loss is associated with altered volatile synthesis and transient changes in DNA methylation

USDA-ARS?s Scientific Manuscript database

Commercial tomatoes are widely perceived by consumers as lacking flavor. A major part of that problem is a postharvest handling system that chills fruit. Low-temperature storage is widely used to slow ripening and reduce decay. However, chilling results in loss of flavor. Flavor-associated volatiles...

Eco-Theatre and New Media: Devising toward Transnational Balance

ERIC Educational Resources Information Center

Glazier, Marnie J.

2012-01-01

This dissertation seeks to address the pivotal ecological and technological realities of the twenty-first century, currently giving rise to new patterns of existence and new paradigms of human inquiry. This study will ask how technological innovation and environmental urgency have altered the ways in which human beings think, and thus perceive the…

Substitution of Marijuana for Alcohol: The Role of Perceived Access and Harm

ERIC Educational Resources Information Center

Alter, Randi J.; Lohrmann, David K.; Greene, Robert

2006-01-01

Research has shown significant declines in gateway drug use among participants in a school/community substance abuse prevention intervention in a midwestern, suburban school district (Lohrmann, Alter, Greene, & Younoszai, 2005). Though still at or below national levels, student marijuana use was not impacted as positively. The current study…

Immune responsiveness and risk of illness in U.S. Air Force Academy cadets during basic cadet training

NASA Technical Reports Server (NTRS)

Lee, David J.; Meehan, Richard T.; Robinson, Christine; Mabry, Thomas R.; Smith, Morey L.

1992-01-01

It has been proposed, but not confirmed, that environmental stressors alter immune function and increase the risk of viral infection among healthy individuals. This hypothesis was evaluated by examining the relationship among stress, immune function, and illness in 96 first-year U.S. Air Force Academy cadets during orientation and four weeks later during the stressful environment of basic cadet training (BCT). Perceived stress and well-being levels of cadets were assessed via questionnaire. Immune responsiveness was analyzed by PHA-stimulated thymidine uptake in mononuclear leucocytes and by serologic evidence of reactivation of the Epstein-Barr virus (EBV). Results showed significant declines in in vitro PHA-induced lymphocyte transformation (-35 percent)and subjective well-being (-19 percent) from orientation to BCT with corresponding, significant increases in perceived stress (+32 percent). Despite significantly altered in vitro immune responsiveness, there was no serologic evidence of EBV reactivation nor was there an association between these measures and risk of illness as determined by medical chart review and self-reported symptoms.

Differential brain responses to cries of infants with autistic disorder and typical development: an fMRI study.

PubMed

Venuti, Paola; Caria, Andrea; Esposito, Gianluca; De Pisapia, Nicola; Bornstein, Marc H; de Falco, Simona

2012-01-01

This study used fMRI to measure brain activity during adult processing of cries of infants with autistic disorder (AD) compared to cries of typically developing (TD) infants. Using whole brain analysis, we found that cries of infants with AD compared to those of TD infants elicited enhanced activity in brain regions associated with verbal and prosodic processing, perhaps because altered acoustic patterns of AD cries render them especially difficult to interpret, and increased activity in brain regions associated with emotional processing, indicating that AD cries also elicit more negative feelings and may be perceived as more aversive and/or arousing. Perceived distress engendered by AD cries related to increased activation in brain regions associated with emotional processing. This study supports the hypothesis that cry is an early and meaningful anomaly displayed by children with AD. It could be that cries associated with AD alter parent-child interactions much earlier than the time that reliable AD diagnosis normally occurs. Copyright © 2012 Elsevier Ltd. All rights reserved.

Congenital heart disease affects cerebral size but not brain growth.

PubMed

Ortinau, Cynthia; Inder, Terrie; Lambeth, Jennifer; Wallendorf, Michael; Finucane, Kirsten; Beca, John

2012-10-01

Infants with congenital heart disease (CHD) have delayed brain maturation and alterations in brain volume. Brain metrics is a simple measurement technique that can be used to evaluate brain growth. This study used brain metrics to test the hypothesis that alterations in brain size persist at 3 months of age and that infants with CHD have slower rates of brain growth than control infants. Fifty-seven infants with CHD underwent serial brain magnetic resonance imaging (MRI). To evaluate brain growth across the first 3 months of life, brain metrics were undertaken using 19 tissue and fluid spaces shown on MRIs performed before surgery and again at 3 months of age. Before surgery, infants with CHD have smaller frontal, parietal, cerebellar, and brain stem measures (p < 0.001). At 3 months of age, alterations persisted in all measures except the cerebellum. There was no difference between control and CHD infants in brain growth. However, the cerebellum trended toward greater growth in infants with CHD. Somatic growth was the primary factor that related to brain growth. Presence of focal white matter lesions before and after surgery did not relate to alterations in brain size or growth. Although infants with CHD have persistent alterations in brain size at 3 months of age, rates of brain growth are similar to that of healthy term infants. Somatic growth was the primary predictor of brain growth, emphasizing the importance of optimal weight gain in this population.

Controlled transport of latex beads through vertically aligned carbon nanofiber membranes

NASA Astrophysics Data System (ADS)

Zhang, L.; Melechko, A. V.; Merkulov, V. I.; Guillorn, M. A.; Simpson, M. L.; Lowndes, D. H.; Doktycz, M. J.

2002-07-01

Stripes of vertically aligned carbon nanofibers (VACNFs) have been used to form membranes for size selectively controlling the transport of latex beads. Fluidic structures were created in poly(dimethylsiloxane) (PDMS) and interfaced to the VACNF structures for characterization of the membrane pore size. Solutions of fluorescently labeled latex beads were introduced into the PDMS channels and characterized by fluorescence and scanning electron microscopy. Results show that the beads size selectively pass through the nanofiber barriers and the size restriction limit correlates with the interfiber spacing. The results suggest that altering VACNF array density can alter fractionation properties of the membrane. Such membranes may be useful for molecular sorting and for mimicking the properties of natural membranes.

Women with spontaneous 46,XX primary ovarian insufficiency (hypergonadotropic hypogonadism) have lower perceived social support than control women

PubMed Central

Orshan, Susan A.; Ventura, June L.; Covington, Sharon N.; Vanderhoof, Vien H.; Troendle, James F.; Nelson, Lawrence M.

2009-01-01

Objective To test the hypothesis that women with spontaneous primary ovarian insufficiency differ from control women with regard to perceived social support and to investigate the relationship between perceived social support and self-esteem. Design Cross-sectional Setting Mark O. Hatfield Clinical Research Center, National Institutes of Health. Patient(s) Women diagnosed with spontaneous primary ovarian insufficiency (N=154) at a mean age of 27 years and healthy control women (N=63). Intervention(s) Administration of validated self-reporting instruments. Main Outcome Measure(s) Personal Resource Questionnaire-85 (PRQ85), Rosenberg Self-Esteem Scale Result(s) Women with primary ovarian insufficiency had significantly lower scores than controls on the perceived social support scale and the self-esteem scale. The findings remained significant after modeling with multivariate regression for differences in age, marital status, and having children. In patients there was a significant positive correlation between self-esteem scores and perceived social support. We found no significant differences in perceived social support or self-esteem related to marital status, whether or not they had children, or time since diagnosis. Conclusion(s) This evidence supports the need for prospective controlled studies. Strategies to improve social support and self-esteem might provide a therapeutic approach to reduce the emotional suffering that accompanies the life-altering diagnosis of spontaneous primary ovarian insufficiency. PMID:18829005

Components of family history associated with women's disease perceptions for cancer: A report from the Family Healthware™ Impact Trial

PubMed Central

Rubinstein, Wendy S.; O'Neill, Suzanne M.; Rothrock, Nan; Starzyk, Erin J.; Beaumont, Jennifer L.; Acheson, Louise S.; Wang, Catharine; Gramling, Robert; Galliher, James M.; Ruffin, Mack T.

2014-01-01

Purpose To determine the specific components of family history and personal characteristics related to disease perceptions about breast, colon, and ovarian cancers. Methods Baseline, cross-sectional data on 2,505 healthy women aged 35–65 years enrolled from 41 primary care practices in the cluster-randomized Family Healthware™ Impact Trial, assessed for detailed family history and perceived risk, perceived severity, worry, and perceived control over getting six common diseases including breast, colon, and ovarian cancers. Results Participants provided family history information on 41,841 total relatives. We found evidence of underreporting of paternal family history and lower perceived breast cancer risk with cancer in the paternal versus maternal lineage. We observed cancer-specific perceived risks and worry for individual family history elements and also found novel “spillover” effects where a family history of one cancer was associated with altered disease perceptions of another. Having a mother with early-onset breast or ovarian cancer was strongly associated with perceived risk of breast cancer. Age, parenthood, and affected lineage were associated with disease perceptions and ran counter to empiric risks. Conclusions Understanding patients' formulation of risk for multiple diseases is important for public health initiatives that seek to inform risk appraisal, influence disease perceptions, or match preventive interventions to existing risk perceptions. PMID:21150785

Ideal Body Size as a Mediator for the Gender-Specific Association between Socioeconomic Status and Body Mass Index: Evidence from an Upper-Middle-Income Country in the African Region

ERIC Educational Resources Information Center

Yepes, Maryam; Maurer, Jürgen; Stringhini, Silvia; Viswanathan, Barathi; Gedeon, Jude; Bovet, Pascal

2016-01-01

Background: While obesity continues to rise globally, the associations between body size, gender, and socioeconomic status (SES) seem to vary in different populations, and little is known on the contribution of perceived ideal body size in the social disparity of obesity in African countries. Purpose: We examined the gender and socioeconomic…

Role of parafovea in blur perception.

PubMed

Venkataraman, Abinaya Priya; Radhakrishnan, Aiswaryah; Dorronsoro, Carlos; Lundström, Linda; Marcos, Susana

2017-09-01

The blur experienced by our visual system is not uniform across the visual field. Additionally, lens designs with variable power profile such as contact lenses used in presbyopia correction and to control myopia progression create variable blur from the fovea to the periphery. The perceptual changes associated with varying blur profile across the visual field are unclear. We therefore measured the perceived neutral focus with images of different angular subtense (from 4° to 20°) and found that the amount of blur, for which focus is perceived as neutral, increases when the stimulus was extended to cover the parafovea. We also studied the changes in central perceived neutral focus after adaptation to images with similar magnitude of optical blur across the image or varying blur from center to the periphery. Altering the blur in the periphery had little or no effect on the shift of perceived neutral focus following adaptation to normal/blurred central images. These perceptual outcomes should be considered while designing bifocal optical solutions for myopia or presbyopia. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

A psychophysiological evaluation of the perceived urgency of auditory warning signals

NASA Technical Reports Server (NTRS)

Burt, J. L.; Bartolome, D. S.; Burdette, D. W.; Comstock, J. R. Jr

1995-01-01

One significant concern that pilots have about cockpit auditory warnings is that the signals presently used lack a sense of priority. The relationship between auditory warning sound parameters and perceived urgency is, therefore, an important topic of enquiry in aviation psychology. The present investigation examined the relationship among subjective assessments of urgency, reaction time, and brainwave activity with three auditory warning signals. Subjects performed a tracking task involving automated and manual conditions, and were presented with auditory warnings having various levels of perceived and situational urgency. Subjective assessments revealed that subjects were able to rank warnings on an urgency scale, but rankings were altered after warnings were mapped to a situational urgency scale. Reaction times differed between automated and manual tracking task conditions, and physiological data showed attentional differences in response to perceived and situational warning urgency levels. This study shows that the use of physiological measures sensitive to attention and arousal, in conjunction with behavioural and subjective measures, may lead to the design of auditory warnings that produce a sense of urgency in an operator that matches the urgency of the situation.

Altered Sense of Body Ownership and Agency in Posttraumatic Stress Disorder and Its Dissociative Subtype: A Rubber Hand Illusion Study.

PubMed

Rabellino, Daniela; Burin, Dalila; Harricharan, Sherain; Lloyd, Chantelle; Frewen, Paul A; McKinnon, Margaret C; Lanius, Ruth A

2018-01-01

Traumatic experiences have been linked to the development of altered states of consciousness affecting bodily perception, including alterations in body ownership and in sense of agency, the conscious experience of the body as one's own and under voluntary control. Severe psychological trauma and prolonged distress may lead to posttraumatic stress disorder (PTSD). Together, symptoms of derealization and, related specifically to the sense of body ownership and agency, of depersonalization (where parts of the body or the entire body itself is perceived as detached and out of control), constitute the dissociative subtype (PTSD+DS). In this study, we explored the Rubber Hand Illusion, an experimental paradigm utilized to manipulate sense of body ownership in PTSD ( n = 4) and PTSD+DS ( n = 6) as compared to healthy controls ( n = 7). Perceived finger location and self-report questionnaires were used as behavioral and subjective measures of the illusion, respectively. In addition, the correlation between the illusion's effect and sense of agency as a continuous feeling of controlling one's own body movements was explored. Here, a lower illusion effect was observed in the PTSD as compared to the control group after synchronous stimulation for both the proprioceptive drift and subjectively perceived illusion. Moreover, by both proprioceptive drift and by subjective ratings, the PTSD+DS group showed a response characterized by high variance, ranging from a very strong to a very weak effect of the illusion. Finally, sense of agency showed a trend toward a negative correlation with the strength of the illusion as subjectively perceived by participants with PTSD and PTSD+DS. These findings suggest individuals with PTSD may, at times, maintain a rigid representation of the body as an avoidance strategy, with top-down cognitive processes weakening the impact of manipulation of body ownership. By contrast, the response elicited in PTSD+DS appeared to be driven by either an increased vulnerability to manipulation of embodiment or by a dominant top-down cognitive representation of the body, with disruption of multisensory integration processes likely in both cases. Taken together, these findings further our understanding of bodily consciousness in PTSD and its dissociative subtype and highlight the supportive role played by sense of agency for the maintenance of body ownership.

Altered Sense of Body Ownership and Agency in Posttraumatic Stress Disorder and Its Dissociative Subtype: A Rubber Hand Illusion Study

PubMed Central

Rabellino, Daniela; Burin, Dalila; Harricharan, Sherain; Lloyd, Chantelle; Frewen, Paul A.; McKinnon, Margaret C.; Lanius, Ruth A.

2018-01-01

Traumatic experiences have been linked to the development of altered states of consciousness affecting bodily perception, including alterations in body ownership and in sense of agency, the conscious experience of the body as one's own and under voluntary control. Severe psychological trauma and prolonged distress may lead to posttraumatic stress disorder (PTSD). Together, symptoms of derealization and, related specifically to the sense of body ownership and agency, of depersonalization (where parts of the body or the entire body itself is perceived as detached and out of control), constitute the dissociative subtype (PTSD+DS). In this study, we explored the Rubber Hand Illusion, an experimental paradigm utilized to manipulate sense of body ownership in PTSD (n = 4) and PTSD+DS (n = 6) as compared to healthy controls (n = 7). Perceived finger location and self-report questionnaires were used as behavioral and subjective measures of the illusion, respectively. In addition, the correlation between the illusion's effect and sense of agency as a continuous feeling of controlling one's own body movements was explored. Here, a lower illusion effect was observed in the PTSD as compared to the control group after synchronous stimulation for both the proprioceptive drift and subjectively perceived illusion. Moreover, by both proprioceptive drift and by subjective ratings, the PTSD+DS group showed a response characterized by high variance, ranging from a very strong to a very weak effect of the illusion. Finally, sense of agency showed a trend toward a negative correlation with the strength of the illusion as subjectively perceived by participants with PTSD and PTSD+DS. These findings suggest individuals with PTSD may, at times, maintain a rigid representation of the body as an avoidance strategy, with top-down cognitive processes weakening the impact of manipulation of body ownership. By contrast, the response elicited in PTSD+DS appeared to be driven by either an increased vulnerability to manipulation of embodiment or by a dominant top-down cognitive representation of the body, with disruption of multisensory integration processes likely in both cases. Taken together, these findings further our understanding of bodily consciousness in PTSD and its dissociative subtype and highlight the supportive role played by sense of agency for the maintenance of body ownership. PMID:29765311

Heart rate variability during acute psychosocial stress: A randomized cross-over trial of verbal and non-verbal laboratory stressors.

PubMed

Brugnera, Agostino; Zarbo, Cristina; Tarvainen, Mika P; Marchettini, Paolo; Adorni, Roberta; Compare, Angelo

2018-05-01

Acute psychosocial stress is typically investigated in laboratory settings using protocols with distinctive characteristics. For example, some tasks involve the action of speaking, which seems to alter Heart Rate Variability (HRV) through acute changes in respiration patterns. However, it is still unknown which task induces the strongest subjective and autonomic stress response. The present cross-over randomized trial sought to investigate the differences in perceived stress and in linear and non-linear analyses of HRV between three different verbal (Speech and Stroop) and non-verbal (Montreal Imaging Stress Task; MIST) stress tasks, in a sample of 60 healthy adults (51.7% females; mean age = 25.6 ± 3.83 years). Analyses were run controlling for respiration rates. Participants reported similar levels of perceived stress across the three tasks. However, MIST induced a stronger cardiovascular response than Speech and Stroop tasks, even after controlling for respiration rates. Finally, women reported higher levels of perceived stress and lower HRV both at rest and in response to acute psychosocial stressors, compared to men. Taken together, our results suggest the presence of gender-related differences during psychophysiological experiments on stress. They also suggest that verbal activity masked the vagal withdrawal through altered respiration patterns imposed by speaking. Therefore, our findings support the use of highly-standardized math task, such as MIST, as a valid and reliable alternative to verbal protocols during laboratory studies on stress. Copyright © 2018 Elsevier B.V. All rights reserved.

Successful E-Learning in Small and Medium-Sized Enterprises

ERIC Educational Resources Information Center

Paulsen, Morten Flate

2009-01-01

So far, e-learning has primarily been used when there are many learners involved. The up-front investments related to e-learning are relatively high, and may be perceived as prohibitive for small and medium-sized enterprises (SMEs). Some e-learning is, however, getting less expensive, and some e-learning models are more suited for small-scale…

What Does School Size Do: Safety Perceptions of Educators and Students

ERIC Educational Resources Information Center

Bakioglu, Aysen; Geyin, Cigdem

2009-01-01

The purpose of this study is to find out how teachers, principals, vice principals and students perceive school safety and how that differs related to school size. 194 educators and 1420 students' views were elicited by two self-deviced school safety inventories conducted in 10 state high schools in Istanbul in 2008. Cronbach alpha value for…

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

Lin, Qingqing; Li, Huilin; Wang, Tong

Perfringolysin O (PFO) is a transmembrane (TM) β-barrel protein that inserts into mammalian cell membranes. Once inserted into membranes, PFO assembles into pore-forming oligomers containing 30–50 PFO monomers. These form a pore of up to 300 Å, far exceeding the size of most other proteinaceous pores. In this study, we found that altering PFO TM segment length can alter the size of PFO pores. A PFO mutant with lengthened TM segments oligomerized to a similar extent as wild-type PFO, and exhibited pore-forming activity and a pore size very similar to wild-type PFO as measured by electron microscopy and a leakagemore » assay. In contrast, PFO with shortened TM segments exhibited a large reduction in pore-forming activity and pore size. This suggests that the interaction between TM segments can greatly affect the size of pores formed by TM β-barrel proteins. PFO may be a promising candidate for engineering pore size for various applications.« less

The Influence of Neighborhood Aesthetics, Safety, and Social Cohesion on Perceived Stress in Disadvantaged Communities.

PubMed

Henderson, Heather; Child, Stephanie; Moore, Spencer; Moore, Justin B; Kaczynski, Andrew T

2016-09-01

Limited research has explored how specific elements of physical and social environments influence mental health indicators such as perceived stress, or whether such associations are moderated by gender. This study examined the relationship between selected neighborhood characteristics and perceived stress levels within a primarily low-income, older, African-American population in a mid-sized city in the Southeastern U.S. Residents (n = 394; mean age=55.3 years, 70.9% female, 89.3% African American) from eight historically disadvantaged neighborhoods completed surveys measuring perceptions of neighborhood safety, social cohesion, aesthetics, and stress. Multivariate linear regression models examined the association between each of the three neighborhood characteristics and perceived stress. Greater perceived safety, improved neighborhood aesthetics, and social cohesion were significantly associated with lower perceived stress. These associations were not moderated by gender. These findings suggest that improving social attributes of neighborhoods may have positive impacts on stress and related benefits for population health. Future research should examine how neighborhood characteristics influence stress over time. © Society for Community Research and Action 2016.

Reducing workplace burnout: the relative benefits of cardiovascular and resistance exercise

PubMed Central

Bretland, Rachel Judith

2015-01-01

Objectives. The global burden of burnout cost is in excess of $300 billion annually. Locally, just under half of working Australians experience high levels of occupational burnout. Consequently, burnout interventions are paramount to organisational productivity. Exercise has the potential to provide a multilevel and cost effective burnout intervention. The current study aims to extend the literature by comparing cardiovascular with resistance exercise to assess their relative effectiveness against well-being, perceived stress, and burnout. Design. Participants were 49 (36 females and 13 males) previously inactive volunteers ranging in age from 19 to 68 that completed a four week exercise program of either cardiovascular, resistance, or no exercise (control). Randomised control trial design was employed. Method. Participants were measured against the Subjective Exercise Experience Scale, the Perceived Stress Scale, and the Maslach Burnout Inventory. Results. After four weeks of exercise participants had greater positive well-being and personal accomplishment, and concomitantly less psychological distress, perceived stress, and emotional exhaustion. Cardiovascular exercise was found to increase well-being and decrease psychological distress, perceived stress, and emotional exhaustion. Resistance training was noticeably effective in increasing well-being and personal accomplishment and to reduce perceived stress. The present findings revealed large effect sizes suggesting that exercise may be an effective treatment for burnout. However, given a small sample size further research needs to be conducted. Conclusion. Exercise has potential to be an effective burnout intervention. Different types of exercise may assist employees in different ways. Organisations wishing to proactively reduce burnout can do so by encouraging their employees to access regular exercise programs. PMID:25870778

The impact of structural packaging design on young adult smokers' perceptions of tobacco products.

PubMed

Borland, Ron; Savvas, Steven; Sharkie, Fiona; Moore, Karen

2013-03-01

To examine the extent that novel cigarette pack shapes and openings have on smokers' perceptions of those packs and the cigarettes contained within. Using a web-based survey, 160 young adult ever-smokers (18-29 years) were shown computer images of plain packaged cigarette packs in five different shapes. This was followed by packs illustrating five different methods of opening. Brand (prestige or budget) and size of the health warnings (30% or 70% warning size) were between-subject conditions. Respondents ranked packs on attractiveness, perceived quality of the cigarettes contained within and extent that the pack distracted from health warnings. Ratings of attractiveness and perceived quality were significantly associated in both substudies, but tendency to distract from warnings was more independent. Significant differences were found between the pack shapes on attractiveness, perceived quality and distraction from warnings. Standard, 2×10 and 4×5 packs were ranked less attractive than Bevelled and Rounded packs. 2×10 and 4×5 packs were also perceived as lower quality than Bevelled and Rounded packs. The Standard pack was less distracting to health warnings than all other shapes except the 2×10 pack. Pack openings were perceived as different on quality of cigarettes contained and extent of distraction to warnings. The Standard Flip-top was rated significantly lower in distracting from warnings than all other openings. Pack shape and pack opening affect ever-smokers' perceptions of the packs and the cigarettes they contain. This means that they have the potential to create appeal and differentiate products and thus should be regulated.

Reducing workplace burnout: the relative benefits of cardiovascular and resistance exercise.

PubMed

Bretland, Rachel Judith; Thorsteinsson, Einar Baldvin

2015-01-01

Objectives. The global burden of burnout cost is in excess of $300 billion annually. Locally, just under half of working Australians experience high levels of occupational burnout. Consequently, burnout interventions are paramount to organisational productivity. Exercise has the potential to provide a multilevel and cost effective burnout intervention. The current study aims to extend the literature by comparing cardiovascular with resistance exercise to assess their relative effectiveness against well-being, perceived stress, and burnout. Design. Participants were 49 (36 females and 13 males) previously inactive volunteers ranging in age from 19 to 68 that completed a four week exercise program of either cardiovascular, resistance, or no exercise (control). Randomised control trial design was employed. Method. Participants were measured against the Subjective Exercise Experience Scale, the Perceived Stress Scale, and the Maslach Burnout Inventory. Results. After four weeks of exercise participants had greater positive well-being and personal accomplishment, and concomitantly less psychological distress, perceived stress, and emotional exhaustion. Cardiovascular exercise was found to increase well-being and decrease psychological distress, perceived stress, and emotional exhaustion. Resistance training was noticeably effective in increasing well-being and personal accomplishment and to reduce perceived stress. The present findings revealed large effect sizes suggesting that exercise may be an effective treatment for burnout. However, given a small sample size further research needs to be conducted. Conclusion. Exercise has potential to be an effective burnout intervention. Different types of exercise may assist employees in different ways. Organisations wishing to proactively reduce burnout can do so by encouraging their employees to access regular exercise programs.

Proprioceptive role for palisade endings in extraocular muscles: evidence from the Jendrassik Maneuver.

PubMed

Niechwiej-Szwedo, E; González, E; Bega, S; Verrier, M C; Wong, A M; Steinbach, M J

2006-07-01

A proprioceptive hypothesis for the control of eye movements has been recently proposed based on neuroanatomical tracing studies. It has been suggested that the non-twitch motoneurons could be involved in modulating the gain of sensory feedback from the eye muscles analogous to the gamma (gamma) motoneurons which control the gain of proprioceptive feedback in skeletal muscles. We conducted behavioral and psychophysical experiments to test the above hypothesis using the Jendrassik Maneuver (JM) to alter the activity of gamma motoneurons. It was hypothesized that the JM would alter the proprioceptive feedback from the eye muscles which would result in misregistration of eye position and mislocalization of targets. In the first experiment, vergence eye movements and pointing responses were examined. Data showed that the JM affected the localization responses but not the actual eye position. Perceptual judgments were tested in the second experiment, and the results showed that targets were perceived as farther when the afferent feedback was altered by the JM. Overall, the results from the two experiments showed that eye position was perceived as more divergent with the JM, but the actual eye movements were not affected. We tested this further in Experiment 3 by examining the effect of JM on the amplitude and velocity of saccadic eye movements. As expected, there were no significant differences in saccadic parameters between the control and experimental conditions. Overall, the present study provides novel insight into the mechanism which may be involved in the use of sensory feedback from the eye muscles. Data from the first two experiments support the hypothesis that the JM alters the registered eye position, as evidenced by the localization errors. We propose that the altered eye position signal is due to the effect of the JM which changes the gain of the sensory feedback from the eye muscles, possibly via the activity of non-twitch motoneurons.

Stimulus size dependence of hue changes induced by chromatic surrounds.

PubMed

Kellner, Christian Johannes; Wachtler, Thomas

2016-03-01

A chromatic surround induces a change in the perceived hue of a stimulus. This shift in hue depends on the chromatic difference between the stimulus and the surround. We investigated how chromatic induction varies with stimulus size and whether the size dependence depends on the surround hue. Subjects performed asymmetric matching of color stimuli with different sizes in surrounds of different chromaticities. Generally, induced hue shifts decreased with increasing stimulus size. This decrease was quantitatively different for different surround hues. However, when size effects were normalized to an overall induction strength, the chromatic specificity was largely reduced. The separability of inducer chromaticity and stimulus size suggests that these effects are mediated by different neural mechanisms.

Perceived Stress After Acute Myocardial Infarction: A Comparison Between Young and Middle-Aged Women Versus Men.

PubMed

Xu, Xiao; Bao, Haikun; Strait, Kelly M; Edmondson, Donald E; Davidson, Karina W; Beltrame, John F; Bueno, Héctor; Lin, Haiqun; Dreyer, Rachel P; Brush, John E; Spertus, John A; Lichtman, Judith H; DʼOnofrio, Gail; Krumholz, Harlan M

2017-01-01

The aim of the study was to examine how psychological stress changes over time in young and middle-aged patients after experiencing an acute myocardial infarction (AMI) and whether these changes differ between men and women. We analyzed data obtained from 2358 women and 1151 men aged 18 to 55 years hospitalized for AMI. Psychological stress was measured using the 14-item Perceived Stress Scale (PSS-14) at initial hospitalization and at 1 month and 12 months after AMI. We used linear mixed-effects models to examine changes in PSS-14 scores over time and sex differences in these changes, while adjusting for patient characteristics and accounting for correlation among repeated observations within patients. Overall, patients' perceived stress decreased over time, especially during the first month after AMI. Women had higher levels of perceived stress than men throughout the 12-month period (difference in PSS-14 score = 3.63, 95% confidence interval = 3.08 to 4.18, p < .001), but they did not differ in how stress changed over time. Adjustment for patient characteristics did not alter the overall pattern of sex difference in changes of perceived stress over time other than attenuating the magnitude of sex difference in PSS-14 score (difference between women and men = 1.74, 95% confidence interval = 1.32 to 2.16, p < .001). The magnitude of sex differences in perceived stress was similar in patients with versus without post-AMI angina, even though patients with angina experienced less improvement in PSS-14 score than those without angina. In young and middle-aged patients with AMI, women reported higher levels of perceived stress than men throughout the first 12 months of recovery. However, women and men had a similar pattern in how perceived stress changed over time.

Dormancy cues alter insect temperature-size relationships.

PubMed

Clemmensen, Sharon F; Hahn, Daniel A

2015-01-01

Developmental temperatures can have dramatic effects on body size in ectotherms. Thermal plasticity in body size is often viewed in the context of seasonality, but the role of seasonal dormancy responses in generating temperature-size relationships is underappreciated. We used the moth Helicoverpa zea (corn earworm) to examine how photoperiodic seasonal dormancy programming for pupal diapause affects the temperature-size relationship. Specifically, we partition out the contributions of somatic growth versus nutrient storage as fat to the thermal reaction norm for size. With increasing temperature from 16 °C to 20 °C, dormant pupae were both overall larger and progressively fatter than non-dormant pupae. This body mass response is likely driven by concurrent increases in food consumption and longer development times as temperatures increase. Our results demonstrate that seasonal photoperiodic cues can alter temperature-size relationships during pre-dormancy development. For biologists interested in seasonal effects on temperature-size relationships, our results suggest that the key to fully understanding these relationships may lie in integrating multiple seasonal cues and multiple aspects of body size and composition in a nutrient-allocation framework.

The sound of the crowd: auditory information modulates the perceived emotion of a crowd based on bodily expressions.

PubMed

McHugh, Joanna E; Kearney, Gavin; Rice, Henry; Newell, Fiona N

2012-02-01

Although both auditory and visual information can influence the perceived emotion of an individual, how these modalities contribute to the perceived emotion of a crowd of characters was hitherto unknown. Here, we manipulated the ambiguity of the emotion of either a visual or auditory crowd of characters by varying the proportions of characters expressing one of two emotional states. Using an intersensory bias paradigm, unambiguous emotional information from an unattended modality was presented while participants determined the emotion of a crowd in an attended, but different, modality. We found that emotional information in an unattended modality can disambiguate the perceived emotion of a crowd. Moreover, the size of the crowd had little effect on these crossmodal influences. The role of audiovisual information appears to be similar in perceiving emotion from individuals or crowds. Our findings provide novel insights into the role of multisensory influences on the perception of social information from crowds of individuals. PsycINFO Database Record (c) 2012 APA, all rights reserved

An Exploration of College Instructors' Use of Classroom Justice, Power, and Behavior Alteration Techniques

ERIC Educational Resources Information Center

Horan, Sean M.; Myers, Scott A.

2009-01-01

A growing body of research indicates that classroom justice concerns are important to students. When students perceive their instructors are not concerned about justice, they report a host of negative outcomes. Due to the importance of justice assigned to students, the present study sought to understand how instructors view justice. Results…

Audiovisual Speech Perception and Eye Gaze Behavior of Adults with Asperger Syndrome

ERIC Educational Resources Information Center

Saalasti, Satu; Katsyri, Jari; Tiippana, Kaisa; Laine-Hernandez, Mari; von Wendt, Lennart; Sams, Mikko

2012-01-01

Audiovisual speech perception was studied in adults with Asperger syndrome (AS), by utilizing the McGurk effect, in which conflicting visual articulation alters the perception of heard speech. The AS group perceived the audiovisual stimuli differently from age, sex and IQ matched controls. When a voice saying /p/ was presented with a face…

Perceived Life Changes in Adults with Acquired Immunodeficiency Syndrome and Kaposi’s Sarcoma Utilizing a Behavioral Systems Model.

DTIC Science & Technology

1987-01-01

occur"(p.613). It is hoped chat this study will provide a foundation for fur- ther research, a characteristic expectation of descriptive research...providing it to any patient that must alter *their sexual practices. Like the vulvectomy, bilateral orchiectomy, and even ostomy patients, these patients

Phonological and Phonetic Marking of Information Status in Foreign Accent Syndrome

ERIC Educational Resources Information Center

Kuschmann, Anja; Lowit, Anja

2012-01-01

Background: Foreign Accent Syndrome (FAS) is a motor speech disorder in which a variety of segmental and suprasegmental errors lead to the perception of a new accent in speech. Whilst changes in intonation have been identified to contribute considerably to the perceived alteration in accent, research has rarely focused on how these changes impact…

Professional hazards? The impact of models' body size on advertising effectiveness and women's body-focused anxiety in professions that do and do not emphasize the cultural ideal of thinness.

PubMed

Dittmar, Helga; Howard, Sarah

2004-12-01

Previous experimental research indicates that the use of average-size women models in advertising prevents the well-documented negative effect of thin models on women's body image, while such adverts are perceived as equally effective (Halliwell & Dittmar, 2004). The current study extends this work by: (a) seeking to replicate the finding of no difference in advertising effectiveness between average-size and thin models (b) examining level of ideal-body internalization as an individual, internal factor that moderates women's vulnerability to thin media models, in the context of (c) comparing women in professions that differ radically in their focus on, and promotion of, the sociocultural ideal of thinness for women--employees in fashion advertising (n = 75) and teachers in secondary schools (n = 75). Adverts showing thin, average-size and no models were perceived as equally effective. High internalizers in both groups of women felt worse about their body image after exposure to thin models compared to other images. Profession affected responses to average-size models. Teachers reported significantly less body-focused anxiety after seeing average-size models compared to no models, while there was no difference for fashion advertisers. This suggests that women in professional environments with less focus on appearance-related ideals can experience increased body-esteem when exposed to average-size models, whereas women in appearance-focused professions report no such relief.

Decreasing transmembrane segment length greatly decreases perfringolysin O pore size

DOE PAGES

Lin, Qingqing; Li, Huilin; Wang, Tong; ...

2015-04-08

Perfringolysin O (PFO) is a transmembrane (TM) β-barrel protein that inserts into mammalian cell membranes. Once inserted into membranes, PFO assembles into pore-forming oligomers containing 30–50 PFO monomers. These form a pore of up to 300 Å, far exceeding the size of most other proteinaceous pores. In this study, we found that altering PFO TM segment length can alter the size of PFO pores. A PFO mutant with lengthened TM segments oligomerized to a similar extent as wild-type PFO, and exhibited pore-forming activity and a pore size very similar to wild-type PFO as measured by electron microscopy and a leakagemore » assay. In contrast, PFO with shortened TM segments exhibited a large reduction in pore-forming activity and pore size. This suggests that the interaction between TM segments can greatly affect the size of pores formed by TM β-barrel proteins. PFO may be a promising candidate for engineering pore size for various applications.« less

Social Network Characteristics, Social Support, and Cigarette Smoking among Asian/Pacific Islander Young Adults.

PubMed

Pokhrel, Pallav; Fagan, Pebbles; Cassel, Kevin; Trinidad, Dennis R; Kaholokula, Joseph Keawe'aimoku; Herzog, Thaddeus A

2016-06-01

Cigarette smoking may be one of the factors contributing to the high levels of cancer-related mortality experienced by certain Asian/Pacific Islander (A/PI) subgroups (e.g., Native Hawaiian). Given the collectivist cultural orientation attributed to A/PI groups, social strategies are recommended for substance abuse or smoking cessation treatment among A/PI. However, research examining how social network characteristics and social support relate to smoking across A/PI subgroups has been lacking. This study investigated the associations between social network characteristics (e.g., size, composition), perceived social support, and recent cigarette use across Native Hawaiian, Filipino, and East Asian (e.g., Japanese, Chinese) young adults (18-35 year old). Cross-sectional, self-report data were collected from N = 435 participants (M age = 25.6, SD = 8.3; 61% women). Ethnic differences were found in a number of pathways linking social network characteristics, perceived social support, and cigarette smoking. Larger network size was strongly associated with higher perceived social support and lower recent cigarette smoking among Native Hawaiians but not Filipinos or East Asians. Higher perceived social support was associated with lower recent smoking among East Asians and Filipinos but not Native Hawaiians. Implications are discussed with regard to smoking prevention and cessation among A/PI. © Society for Community Research and Action 2016.

Is Hefting to Perceive the Affordance for Throwing a Smart Perceptual Mechanism?

ERIC Educational Resources Information Center

Zhu, Qin; Bingham, Geoffrey P.

2008-01-01

G. P. Bingham, R. C. Schmidt, and L. D. Rosenblum (1989) found that, by hefting objects of different sizes and weights, people could choose the optimal weight in each size for throwing to a maximum distance. In Experiment 1, the authors replicated this result. G. P. Bingham et al. hypothesized that hefting is a smart mechanism that allows objects…

A Case Study and Analysis of a Successful and Collaborative Student-Centered Textbook Reserve Program in a Mid-Size Academic Library

ERIC Educational Resources Information Center

Schlak, Timothy M.; Johnston, Bruce

2018-01-01

This article presents an innovative textbook reserve program at a mid-sized academic library. Research conducted subsequent to the program's launch showed a positive correlation between students' use of the program and their perceived academic success. In addition, the program has proved effective at helping students with college affordability.…

Is hefting to perceive the affordance for throwing a smart perceptual mechanism?

PubMed

Zhu, Qin; Bingham, Geoffrey P

2008-08-01

G. P. Bingham, R. C. Schmidt, and L. D. Rosenblum (1989) found that, by hefting objects of different sizes and weights, people could choose the optimal weight in each size for throwing to a maximum distance. In Experiment 1, the authors replicated this result. G. P. Bingham et al. hypothesized that hefting is a smart mechanism that allows objects to be perceived in the context of throwing dynamics. This hypothesis entails 2 assumptions. First, hefting by hand is required for information about throwing by hand. The authors tested and confirmed this in Experiments 2 and 3. Second, optimal objects are determined by the dynamics of throwing. In Experiment 4, the authors tested this by measuring throwing release angles and using them with mean thrown distances from Experiment 1 and object sizes and weights to simulate projectile motion and recover release velocities. The results showed that only weight, not size, affects throwing. This failed to provide evidence supporting the particular smart mechanism hypothesis of G. P. Bingham et al. Because the affordance relation is determined in part by the dynamics of projectile motion, the results imply that the affordance is learned from knowledge of results of throwing.

Perceived area and the luminosity threshold.

PubMed

Bonato, F; Gilchrist, A L

1999-07-01

Observers made forced-choice opaque/luminous responses to targets of varying luminance and varying size presented (1) on the wall of a laboratory, (2) as a disk within an annulus, and (3) embedded within a Mondrian array presented within a vision tunnel. Lightness matches were also made for nearby opaque surfaces. The results show that the threshold luminance value at which a target begins to appear self-luminous increases with its size, defined as perceived size, not retinal size. More generally, the larger the target, the more an increase in its luminance induces grayness/blackness into the surround and the less it induces luminosity into the target, and vice versa. Corresponding to this luminosity/grayness tradeoff, there appears to be an invariant: Across a wide variety of conditions, a target begins to appear luminous when its luminance is about 1.7 times that of a surface that would appear white in the same illumination. These results show that the luminosity threshold behaves like a surface lightness value--the maximum lightness value, in fact--and is subject to the same laws of anchoring (such as the area rule proposed by Li & Gilchrist, 1999) as surface lightness.

Cyclic development of igneous features and their relationship to high-temperature hydrothermal features in the Henderson porphyry molybdenum deposit, Colorado

USGS Publications Warehouse

Carten, R.B.; Geraghty, E.P.; Walker, B.M.

1988-01-01

The Henderson porphyry molybdenum deposit was formed by the superposition of coupled alteration and mineralization events, of varying intensity and size, that were associated with each of at least 11 intrusions. Deposition of molybdenite was accompanied by time-equivalent silicic and potassic alteration. High-temperature alteration and mineralization are spatially and temporally linked to the crystallization of compositionally zoned magma in the apex of stocks. Differences in hydrothermal features associated with each intrusion (e.g., mass of ore, orientation and type of veins, density of veins, and intensity of alteration) correlate with differences in primary igneous features (e.g., composition, texture, morphology, and size). The systematic relations between hydrothermal and magmatic features suggest that primary magma compositions, including volatile contents, largely control the geometry, volume, level of emplacement, and mechanisms of crystallization of stocks. These elements in turn govern the orientations and densities of fractures, which ultimately determine the distribution patterns of hydrothermal alteration and mineralization. -from Authors

Analysis of Swedish Forest Owners' Information and Knowledge-Sharing Networks for Decision-Making: Insights for Climate Change Communication and Adaptation.

PubMed

André, Karin; Baird, Julia; Gerger Swartling, Åsa; Vulturius, Gregor; Plummer, Ryan

2017-06-01

To further the understanding of climate change adaptation processes, more attention needs to be paid to the various contextual factors that shape whether and how climate-related knowledge and information is received and acted upon by actors involved. This study sets out to examine the characteristics of forest owners' in Sweden, the information and knowledge-sharing networks they draw upon for decision-making, and their perceptions of climate risks, their forests' resilience, the need for adaptation, and perceived adaptive capacity. By applying the concept of ego-network analysis, the empirical data was generated by a quantitative survey distributed to 3000 private forest owners' in Sweden in 2014 with a response rate of 31%. The results show that there is a positive correlation, even though it is generally weak, between forest owner climate perceptions and (i) network features, i.e. network size and heterogeneity, and (ii) presence of certain alter groups (i.e. network members or actors). Results indicate that forest owners' social networks currently serve only a minimal function of sharing knowledge of climate change and adaptation. Moreover, considering the fairly infrequent contact between respondents and alter groups, the timing of knowledge sharing is important. In conclusion we suggest those actors that forest owners' most frequently communicate with, especially forestry experts providing advisory services (e.g. forest owner associations, companies, and authorities) have a clear role to communicate both the risks of climate change and opportunities for adaptation. Peers are valuable in connecting information about climate risks and adaptation to the actual forest property.

Analysis of Swedish Forest Owners' Information and Knowledge-Sharing Networks for Decision-Making: Insights for Climate Change Communication and Adaptation

NASA Astrophysics Data System (ADS)

André, Karin; Baird, Julia; Gerger Swartling, Åsa; Vulturius, Gregor; Plummer, Ryan

2017-06-01

To further the understanding of climate change adaptation processes, more attention needs to be paid to the various contextual factors that shape whether and how climate-related knowledge and information is received and acted upon by actors involved. This study sets out to examine the characteristics of forest owners' in Sweden, the information and knowledge-sharing networks they draw upon for decision-making, and their perceptions of climate risks, their forests' resilience, the need for adaptation, and perceived adaptive capacity. By applying the concept of ego-network analysis, the empirical data was generated by a quantitative survey distributed to 3000 private forest owners' in Sweden in 2014 with a response rate of 31%. The results show that there is a positive correlation, even though it is generally weak, between forest owner climate perceptions and (i) network features, i.e. network size and heterogeneity, and (ii) presence of certain alter groups (i.e. network members or actors). Results indicate that forest owners' social networks currently serve only a minimal function of sharing knowledge of climate change and adaptation. Moreover, considering the fairly infrequent contact between respondents and alter groups, the timing of knowledge sharing is important. In conclusion we suggest those actors that forest owners' most frequently communicate with, especially forestry experts providing advisory services (e.g. forest owner associations, companies, and authorities) have a clear role to communicate both the risks of climate change and opportunities for adaptation. Peers are valuable in connecting information about climate risks and adaptation to the actual forest property.

Family size and effective population size in a hatchery stock of coho salmon (Oncorhynchus kisutch)

USGS Publications Warehouse

Simon, R.C.; McIntyre, J.D.; Hemmingsen, A.R.

1986-01-01

Means and variances of family size measured in five year-classes of wire-tagged coho salmon (Oncorhynchus kisutch) were linearly related. Population effective size was calculated by using estimated means and variances of family size in a 25-yr data set. Although numbers of age 3 adults returning to the hatchery appeared to be large enough to avoid inbreeding problems (the 25-yr mean exceeded 4500), the numbers actually contributing to the hatchery production may be too low. Several strategies are proposed to correct the problem perceived. Argument is given to support the contention that the problem of effective size is fairly general and is not confined to the present study population.

Bigness is in the eye of the beholder. [size and distance perception of pilots in flight

NASA Technical Reports Server (NTRS)

Roscoe, S. N.

1985-01-01

This report reviews an investigation of judgments of size and distance as required of pilots in flight. The experiments covered a broad spectrum of basic psychophysiological issues involving the measurement of visual accommodation and its correlation with various other dependent variables. Psychophysiological issues investigated included the size-distance invariance hypothesis, the projection of afterimages, the moon illusion, night and empty-field myopia, the dark focus and its so-called Mandelbaum effect, the nature and locus of the accommodative stimulus, the relation between accommodation, retinal size, and perceived size, and possible relationships among accommodative responses, autonomic balance, and personality variables.

Intraspecific variation in body size does not alter the effects of mesopredators on prey.

PubMed

Gallagher, Austin J; Brandl, Simon J; Stier, Adrian C

2016-12-01

As humans continue to alter the species composition and size structure of marine food webs, it is critical to understand size-dependent effects of predators on prey. Yet, how shifts in predator body size mediate the effect of predators is understudied in tropical marine ecosystems, where anthropogenic harvest has indirectly increased the density and size of small-bodied predators. Here, we combine field surveys and a laboratory feeding experiment in coral reef fish communities to show that small and large predators of the same species can have similar effects. Specifically, surveys show that the presence of a small predator ( Paracirrhites arcatus ) was correlated with lower chances of prey fish presence, but these correlations were independent of predator size. Experimental trials corroborated the size-independent effect of the predator; attack rates were indistinguishable between small and large predators, suggesting relatively even effects of hawkfish in various size classes on the same type of prey. Our results indicate that the effects of small predators on coral reefs can be size-independent, suggesting that variation in predator size-structure alone may not always affect the functional role of these predators.

Nuclear size is sensitive to NTF2 protein levels in a manner dependent on Ran binding

PubMed Central

Vuković, Lidija D.; Jevtić, Predrag; Zhang, Zhaojie; Stohr, Bradley A.; Levy, Daniel L.

2016-01-01

ABSTRACT Altered nuclear size is associated with many cancers, and determining whether cancer-associated changes in nuclear size contribute to carcinogenesis necessitates an understanding of mechanisms of nuclear size regulation. Although nuclear import rates generally positively correlate with nuclear size, NTF2 levels negatively affect nuclear size, despite the role of NTF2 (also known as NUTF2) in nuclear recycling of the import factor Ran. We show that binding of Ran to NTF2 is required for NTF2 to inhibit nuclear expansion and import of large cargo molecules in Xenopus laevis egg and embryo extracts, consistent with our observation that NTF2 reduces the diameter of the nuclear pore complex (NPC) in a Ran-binding-dependent manner. Furthermore, we demonstrate that ectopic NTF2 expression in Xenopus embryos and mammalian tissue culture cells alters nuclear size. Finally, we show that increases in nuclear size during melanoma progression correlate with reduced NTF2 expression, and increasing NTF2 levels in melanoma cells is sufficient to reduce nuclear size. These results show a conserved capacity for NTF2 to impact on nuclear size, and we propose that NTF2 might be a new cancer biomarker. PMID:26823604

Human Exploration of Enclosed Spaces through Echolocation.

PubMed

Flanagin, Virginia L; Schörnich, Sven; Schranner, Michael; Hummel, Nadine; Wallmeier, Ludwig; Wahlberg, Magnus; Stephan, Thomas; Wiegrebe, Lutz

2017-02-08

Some blind humans have developed echolocation, as a method of navigation in space. Echolocation is a truly active sense because subjects analyze echoes of dedicated, self-generated sounds to assess space around them. Using a special virtual space technique, we assess how humans perceive enclosed spaces through echolocation, thereby revealing the interplay between sensory and vocal-motor neural activity while humans perform this task. Sighted subjects were trained to detect small changes in virtual-room size analyzing real-time generated echoes of their vocalizations. Individual differences in performance were related to the type and number of vocalizations produced. We then asked subjects to estimate virtual-room size with either active or passive sounds while measuring their brain activity with fMRI. Subjects were better at estimating room size when actively vocalizing. This was reflected in the hemodynamic activity of vocal-motor cortices, even after individual motor and sensory components were removed. Activity in these areas also varied with perceived room size, although the vocal-motor output was unchanged. In addition, thalamic and auditory-midbrain activity was correlated with perceived room size; a likely result of top-down auditory pathways for human echolocation, comparable with those described in echolocating bats. Our data provide evidence that human echolocation is supported by active sensing, both behaviorally and in terms of brain activity. The neural sensory-motor coupling complements the fundamental acoustic motor-sensory coupling via the environment in echolocation. SIGNIFICANCE STATEMENT Passive listening is the predominant method for examining brain activity during echolocation, the auditory analysis of self-generated sounds. We show that sighted humans perform better when they actively vocalize than during passive listening. Correspondingly, vocal motor and cerebellar activity is greater during active echolocation than vocalization alone. Motor and subcortical auditory brain activity covaries with the auditory percept, although motor output is unchanged. Our results reveal behaviorally relevant neural sensory-motor coupling during echolocation. Copyright © 2017 the authors 0270-6474/17/371614-14$15.00/0.

The perceptions of UK youth of branded and standardized, 'plain' cigarette packaging.

PubMed

Hammond, David; White, Christine; Anderson, Will; Arnott, Deborah; Dockrell, Martin

2014-08-01

Tobacco packaging is an important form of promotion. Standardizing cigarette packages ('plain' packaging) represents a novel tobacco control policy. This study examined perceptions of branded and standardized cigarette packages among British youth. Seven hundred twelve youth aged 11-17 completed an online survey. Participants viewed pairs of packages altered using a 3 × 2 factorial design: health warning type (40% text, 40% pictorial or 80% pictorial) × standardized pack colour (white vs. brown). A discrete-choice task was used in which participants selected packs based on attractiveness, taste, tar, health risk, impact of health warning and enticement to start smoking. Participants also compared regular Silk Cut and 'Superslims' Silk Cut packs. Participants completed a final selection task from two standardized and two branded packs. Warning type was significantly associated with all six outcomes: packs with larger pictorial warnings were more likely to be perceived as less attractive, less smooth, greater health risk, higher tar delivery, more effective health warnings and less likely to encourage initiation. The same pattern was found for brown vs. white standardized packages, with the exception of attractiveness and initiation. Compared with the regular Silk Cut pack, the 'Superslims' Silk Cut pack was perceived as significantly more favourable on all six outcomes. Finally, among respondents who selected a pack in the pack selection task, 95.1% selected a branded pack vs. 4.9% who selected a standardized pack. Increasing the size of pictorial health warnings and standardizing the appearance and shape of packages may discourage smoking initiation among young people. © The Author 2013. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Cannibalism by damselflies increases with rising temperature

PubMed Central

Kirk, Devin; Shea, Dylan

2017-01-01

Trophic interactions are likely to change under climate warming. These interactions can be altered directly by changing consumption rates, or indirectly by altering growth rates and size asymmetries among individuals that in turn affect feeding. Understanding these processes is particularly important for intraspecific interactions, as direct and indirect changes may exacerbate antagonistic interactions. We examined the effect of temperature on activity rate, growth and intraspecific size asymmetries, and how these temperature dependencies affected cannibalism in Lestes congener, a damselfly with marked intraspecific variation in size. Temperature increased activity rates and exacerbated differences in body size by increasing growth rates. Increased activity and changes in body size interacted to increase cannibalism at higher temperatures. We argue that our results are likely to be general to species with life-history stages that vary in their temperature dependencies, and that the effects of climate change on communities may depend on the temperature dependencies of intraspecific interactions. PMID:28515331

Cannibalism by damselflies increases with rising temperature.

PubMed

Start, Denon; Kirk, Devin; Shea, Dylan; Gilbert, Benjamin

2017-05-01

Trophic interactions are likely to change under climate warming. These interactions can be altered directly by changing consumption rates, or indirectly by altering growth rates and size asymmetries among individuals that in turn affect feeding. Understanding these processes is particularly important for intraspecific interactions, as direct and indirect changes may exacerbate antagonistic interactions. We examined the effect of temperature on activity rate, growth and intraspecific size asymmetries, and how these temperature dependencies affected cannibalism in Lestes congener , a damselfly with marked intraspecific variation in size. Temperature increased activity rates and exacerbated differences in body size by increasing growth rates. Increased activity and changes in body size interacted to increase cannibalism at higher temperatures. We argue that our results are likely to be general to species with life-history stages that vary in their temperature dependencies, and that the effects of climate change on communities may depend on the temperature dependencies of intraspecific interactions. © 2017 The Author(s).

No Differences Between Alter G-Trainer and Active and Passive Recovery Strategies on Isokinetic Strength, Systemic Oxidative Stress and Perceived Muscle Soreness After Exercise-Induced Muscle Damage.

PubMed

Cooke, Matthew B; Nix, Carrie M; Greenwood, Lori D; Greenwood, Mike C

2018-03-01

Cooke, MB, Nix, C, Greenwood, L, and Greenwood, M. No Differences Between Alter G-Trainer and Active and Passive Recovery Strategies on Isokinetic Strength, Systemic Oxidative Stress and Perceived Muscle Soreness After Exercise-Induced Muscle Damage. J Strength Cond Res 32(3): 736-747, 2018-The incidence of muscle injuries is prevalent in elite sport athletes and weekend warriors and strategies that safely and effectively hasten recovery are highly desirable. The purpose of this study was to examine the differences between 3 recovery methods after eliciting muscle damage in recreationally active men relative to maximal isokinetic contractions, perceived muscle soreness, and psychological mood states. Twenty-five recreationally active men (22.15 ± 3.53 years, 75.75 ± 11.91 kg, 180.52 ± 7.3 cm) were randomly matched by V[Combining Dot Above]O2 peak (53.86 ± 6.65 ml·kg·min) and assigned to one of 3 recovery methods: anti-gravity treadmill (G-Trainer) (N = 8), conventional treadmill (N = 8) or static stretching (N = 9). Recovery methods were performed 30 minutes, 24, 48, and 72 hours after a 45-minute downhill run. Following eccentrically biased running, no significant differences were noted in isokinetic knee flexion and extension peak torque, systemic markers of muscle damage, oxidative stress and lipid peroxidation such as serum creatine kinase (CK), superoxide dismutase (SOD), and malondialdehyde (MDA), respectively, and subjective ratings of perceived muscle soreness between recovery methods. The G-Trainer group did however display a higher mood state as indicated by the Profile of Mood State global scores at 24 hours postexercise when compared to the conventional treadmill recovery group (p = 0.035). The improved mood state after the use of the anti-gravity treadmill may provide clinical relevance to other populations.

Growth-Related Neural Reorganization and the Autism Phenotype: A Test of the Hypothesis that Altered Brain Growth Leads to Altered Connectivity

ERIC Educational Resources Information Center

Lewis, John D.; Elman, Jeffrey L.

2008-01-01

Theoretical considerations, and findings from computational modeling, comparative neuroanatomy and developmental neuroscience, motivate the hypothesis that a deviant brain growth trajectory will lead to deviant patterns of change in cortico-cortical connectivity. Differences in brain size during development will alter the relative cost and…

The Impact of Cigarette Plain Packaging on Health Warning Salience and Perceptions: Implications for Public Health Policy.

PubMed

Auemaneekul, Naruemon; Silpasuwan, Pimpan; Sirichotiratana, Nithat; Satitvipawee, Pratana; Sompopcharoen, Malinee; Viwatwongkasem, Chukiat; Sujirarat, Dusit

2015-11-01

The study employed a mixed methods design using focus group interviews with 6 student groups and self-administered questionnaires with 1239 students. The participants were nonsmoking, current smokers, and quit-smoking teenagers from secondary schools and colleges. Focus group revealed that although nonsmoking teenagers perceived fear appeals to warning messages, current smokers did not perceive fear appeals to health. Black and white backgrounds of the cigarette package were chosen as the best color for plain packaging. However, most participants suggested various pictorials and a bigger size of pictorial warnings for greater and more effective fear appeal. Odds ratio showed that males had 2.43 times the odds to perceive intention not to smoke. Teenagers who had never smoked and those who had quit smoking had 13.27 and 3.61 times the odds, respectively, to perceive intention not to smoke. © 2015 APJPH.

Network characteristics, perceived social support, and psychological adjustment in mothers of children with autism spectrum disorder.

PubMed

Benson, Paul R

2012-12-01

This study examined the characteristics of the support networks of 106 mothers of children with ASD and their relationship to perceived social support, depressed mood, and subjective well-being. Using structural equation modeling, two competing sets of hypotheses were assessed: (1) that network characteristics would impact psychological adjustment directly, and (2) that network effects on adjustment would be indirect, mediated by perceived social support. Results primarily lent support to the latter hypotheses, with measures of network structure (network size) and function (proportion of network members providing emotional support) predicting increased levels of perceived social support which, in turn, predicted decreased depressed mood and increased well-being. Results also indicated that increased interpersonal strain in the maternal network was directly and indirectly associated with increased maternal depression, while being indirectly linked to reduced well-being. Study limitations and implications are discussed.

Judging the differences between women's attractiveness and health: is there really a difference between judgments made by men and women?

PubMed

Stephen, Ian D; Perera, A Treshi-marie

2014-03-01

Perceived weight in the face and body size have been shown to be significant predictors of both attractiveness and health. Studies looking at the relationship between attractiveness, perceived health, and perceived weight in faces have found that individuals prefer a lower weight for attractiveness than for apparent health. Here, a group of twenty-four Asian participants were allowed to manipulate the apparent body mass indices (BMIs) of full-length photographs of young Malaysian Chinese women to enhance their perceived healthiness and attractiveness. Results showed that both men and women differentiated between attractiveness and health by preferring a lower BMI for attractiveness than health, suggesting a consistency in the preferred ideal BMI for attractiveness and healthy appearance across both sexes. Results also suggested that BMI provides important cues to judgments of attractive and healthy appearance. Copyright © 2013 Elsevier Ltd. All rights reserved.

Particulate matter in cigarette smoke increases ciliary axoneme beating through mechanical stimulation.

PubMed

Navarrette, Chelsea R; Sisson, Joseph H; Nance, Elizabeth; Allen-Gipson, Diane; Hanes, Justin; Wyatt, Todd A

2012-06-01

The lung's ability to trap and clear foreign particles via the mucociliary elevator is an important mechanism for protecting the lung against respirable irritants and microorganisms. Although cigarette smoke (CS) exposure and particulate inhalation are known to alter mucociliary clearance, little is known about how CS and nanoparticles (NPs) modify cilia beating at the cytoskeletal infrastructure, or axonemal, level. We used a cell-free model to introduce cigarette smoke extract (CSE) and NPs with variant size and surface chemistry to isolated axonemes and measured changes in ciliary motility. We hypothesized that CSE would alter cilia beating and that alterations in ciliary beat frequency (CBF) due to particulate matter would be size- and surface chemistry-dependent. Demembranated axonemes were isolated from ciliated bovine tracheas and exposed to adenosine triphosphate (ATP) to initiate motility. CBF was measured in response to 5% CSE, CSE filtrate, and carboxyl-modified (COOH), sulphate (SO(4))-modified (sulfonated), or PEG-coated polystyrene (PS) latex NPs ranging in size from 40 nm to 500 nm. CSE concentrations as low as 5% resulted in rapid, significant stimulation of CBF (p<0.05 vs. baseline control). Filtering CSE through a 0.2-μm filter attenuated this effect. Introduction of sulphate-modified PS beads ~300 nm in diameter resulted in a similar increase in CBF above baseline ATP levels. Uncharged, PEG-coated beads had no effect on CBF regardless of size. Similarly, COOH-coated particles less than 200 nm in diameter did not alter ciliary motility. However, COOH-coated PS particles larger than 300 nm increased CBF significantly and increased the number of motile points. These data show that NPs, including those found in CSE, mechanically stimulate axonemes in a size- and surface chemistry-dependent manner. Alterations in ciliary motility due to physicochemical properties of NPs may be important for inhalational lung injury and efficient drug delivery of respirable particles.

Ontogenetic functional diversity: size structure of a keystone predator drives functioning of a complex ecosystem.

PubMed

Rudolf, Volker H W; Rasmussen, Nick L

2013-05-01

A central challenge in community ecology is to understand the connection between biodiversity and the functioning of ecosystems. While traditional approaches have largely focused on species-level diversity, increasing evidence indicates that there exists substantial ecological diversity among individuals within species. By far, the largest source of this intraspecific diversity stems from variation among individuals in ontogenetic stage and size. Although such ontogenetic shifts are ubiquitous in natural communities, whether and how they scale up to influence the structure and functioning of complex ecosystems is largely unknown. Here we take an experimental approach to examine the consequences of ontogenetic niche shifts for the structure of communities and ecosystem processes. In particular we experimentally manipulated the stage structure in a keystone predator, larvae of the dragonfly Anax junius, in complex experimental pond communities to test whether changes in the population stage or size structure of a keystone species scale up to alter community structure and ecosystem processes, and how functional differences scale with relative differences in size among stages. We found that the functional role of A. junius was stage-specific. Altering what stages were present in a pond led to concurrent changes in community structure, primary producer biomass (periphyton and phytoplankton), and ultimately altered ecosystem processes (respiration and net primary productivity), indicating a strong, but stage-specific, trophic cascade. Interestingly, the stage-specific effects did not simply scale with size or biomass of the predator, but instead indicated clear ontogenetic niche shifts in ecological interactions. Thus, functional differences among stages within a keystone species scaled up to alter the functioning of entire ecosystems. Therefore, our results indicate that the classical approach of assuming an average functional role of a species can be misleading because functional roles are dynamic and will change with shifts in the stage structure of the species. In general this emphasizes the importance of accounting for functional diversity below the species level to predict how natural and anthropogenic changes alter the functioning of natural ecosystems.

The pleiotropic Arabidopsis frd mutation with altered coordination of chloroplast biogenesis, cell size and differentiation, organ size and number.

PubMed

Sulmon, Cécile; Gouesbet, Gwenola; Couée, Ivan; Cabello-Hurtado, Francisco; Cavalier, Annie; Penno, Christophe; Zaka, Raïhana; Bechtold, Nicole; Thomas, Daniel; El Amrani, Abdelhak

2006-11-01

In higher plants, plastid development must be tightly coordinated with cell and organ development. In this paper, a novel T-DNA-mutagenized Arabidopsis line showing chlorotic leaves and minute stature was identified in a genetic screen for altered chloroplast development. The mutation corresponded to a single locus on chromosome IV and was associated with insertion of the T-DNA. This locus was named FARFADET and resulted in pleiotropic effects on chloroplast biogenesis, cell size and differentiation, organ size and number. Thus, in contrast with previously described chlorotic mutants, frd mutants were affected not only in chloroplast development and chlorophyll accumulation, but also in cell and organ development. Alteration of differentiation affected different cell types such as leaf epidermal cells, trichomes, mesophyll cells, and columella cells. A major effect on mesophyll cell differentiation was the lack of palisadic parenchyma and absence of grana stacks. Moreover, meristem size and lateral meristem initiation were affected. Genetic and molecular characterisation showed that the T-DNA insertion generated 41 bp deletion in a potential miRNA precursor. The predicted miRNA target genes were involved in plant development and stress. It is therefore hypothesized that the frd mutation had affected coordination of cell developmental span and the control of the division-differentiation balance.

Tetrahedron deformation and alignment of perceived vorticity and strain in a turbulent flow

NASA Astrophysics Data System (ADS)

Pumir, Alain; Bodenschatz, Eberhard; Xu, Haitao

2013-03-01

We describe the structure and dynamics of turbulence by the scale-dependent perceived velocity gradient tensor as supported by following four tracers, i.e., fluid particles, that initially form a regular tetrahedron. We report results from experiments in a von Kármán swirling water flow and from numerical simulations of the incompressible Navier-Stokes equation. We analyze the statistics and the dynamics of the perceived rate of strain tensor and vorticity for initially regular tetrahedron of size r0 from the dissipative to the integral scale. Just as for the true velocity gradient, at any instant, the perceived vorticity is also preferentially aligned with the intermediate eigenvector of the perceived rate of strain. However, in the perceived rate of strain eigenframe fixed at a given time t = 0, the perceived vorticity evolves in time such as to align with the strongest eigendirection at t = 0. This also applies to the true velocity gradient. The experimental data at the higher Reynolds number suggests the existence of a self-similar regime in the inertial range. In particular, the dynamics of alignment of the perceived vorticity and strain can be rescaled by t0, the turbulence time scale of the flow when the scale r0 is in the inertial range. For smaller Reynolds numbers we found the dynamics to be scale dependent.

Impact of hospital atmosphere on perceived health care outcome.

PubMed

Narang, Ritu; Polsa, Pia; Soneye, Alabi; Fuxiang, Wei

2015-01-01

Healthcare service quality studies primarily examine the relationships between patients' perceived quality and satisfaction with healthcare services, clinical effectiveness, service use, recommendations and value for money. These studies suggest that patient-independent quality dimensions (structure, process and outcome) are antecedents to quality. The purpose of this paper is to propose an alternative by looking at the relationship between hospital atmosphere and healthcare quality with perceived outcome. Data were collected from Finland, India, Nigeria and the People's Republic of China. Regression analysis used perceived outcome as the dependent variable and atmosphere and healthcare service quality as independent variables. Findings - Results showed that atmosphere and healthcare service quality have a statistically significant relationship with patient perceived outcomes. The sample size was small and the sampling units were selected on convenience; thus, caution must be exercised in generalizing the findings. The study determined that service quality and atmosphere are considered significant for developing and developed nations. This result could have significant implications for policy makers and service providers developing healthcare quality and hospital atmosphere. Studies concentrate on healthcare outcome primarily regarding population health status, mortality, morbidity, customer satisfaction, loyalty, quality of life, customer behavior and consumption. However, the study exposes how patients perceive their health after treatment. Furthermore, the authors develop the healthcare service literature by considering atmosphere and perceived outcome.

Perceived food intolerance and irritable bowel syndrome in a population 3 years after a giardiasis-outbreak: a historical cohort study.

PubMed

Litleskare, Sverre; Wensaas, Knut-Arne; Eide, Geir Egil; Hanevik, Kurt; Kahrs, Gudrun Elise; Langeland, Nina; Rortveit, Guri

2015-11-19

Studies have shown an increased prevalence of irritable bowel syndrome (IBS) after acute gastroenteritis. Food as a precipitating and perpetuating factor in IBS has gained recent interest, but food intolerance following gastroenteritis is less investigated. The aims of this study were firstly, to compare perceived food intolerance in a group previously exposed to Giardia lamblia with a control group; secondly, to explore the relation with IBS status; and thirdly, to investigate associations with content of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) in foods reported. This is a historical cohort study with mailed questionnaire to 1252 Giardia exposed and a control cohort matched by gender and age. Differences between groups were investigated using bivariate and multivariate analyses. The questionnaire response rate in the exposed group was 65.3 % (817/1252) and in the control group 31.4 % (1128/3598). The adjusted odds ratio (OR) for perceived food intolerance for the exposed group was 2.00 with 95 % confidence interval (CI): 1.65 to 2.42, as compared with the control group. Perceived intolerance for dairy products was the most frequently reported intolerance, with an adjusted OR for the exposed of 1.95 (95 % CI: 1.51 to 2.51). Perceived intolerance for fatty foods, vegetables, fruit, cereals and alcohol was also significantly higher in the exposed group. The groups did not differ in perceived intolerance to spicy foods, coffee or soda. The association between exposure to Giardia infection and perceived food intolerance differed between the IBS group and the no-IBS group, but IBS was not a significant effect modifier for the association. Perceived intolerance for high FODMAP foods (adjusted OR 1.91) and low FODMAP foods (adjusted OR 1.55) was significantly associated with exposure status. Exposure to Giardia infection was associated with perceived food intolerance 3 years after giardiasis. IBS status did not alter the association between exposure status and perceived food intolerance. Perceived intolerance to high FODMAP foods and low FODMAP foods were both statistically significantly associated with exposure to Giardia infection.

Women and the Engineering Profession: the Stereotypical Engineer

NASA Astrophysics Data System (ADS)

Cory, Suzanne N.; Rezaie, Bahman

The paucity of female engineers has been a problem for years, and most universities suffer from a lack of women majoring in engineering. It is possible that the stereotypical image or perceived gender of engineers may deter young women from considering a career in the field. In order to determine whether 1st-year college students held perceptions regarding personality traits and probable gender of an engineer, a survey was developed based on the Personality Factor (PF) questionnaire originally developed by Cattell (1943). Results indicate that personality traits most often associated with engineers were primarily masculine. Also, engineers were most often expected to be male, especially by the females in this study. Perceived personality traits and the probable gender of engineers were compared to those of 5 other professions: accountants, lawyers, physicians, insurance broker/agents, and computer and information systems specialists. Several differences in perceived personality traits were found. In addition, engineers were perceived as more likely to be male than members of all of the other occupations studied except computer and information systems specialists. Possible approaches to begin altering young women's perceptions of personality traits and the probably gender of a stereotypical engineer are discussed.

The effect of e-cigarette warning labels on college students' perception of e-cigarettes and intention to use e-cigarettes.

PubMed

Lee, Hsiao-Yun; Lin, Hsien-Chang; Seo, Dong-Chul; Lohrmann, David K

2018-01-01

This study examined the effect of two e-cigarette warning labels on college students' perceived advantages and risks of e-cigarette use, as well as students' intentions to use e-cigarettes. The company-produced e-cigarette warning label carries abundant information with small font size while the governmental warning label has only two sentences presented in large font size. The effect of both labels have not yet been examined and verified. Data were collected in October 2015 from college students at a Midwestern university. A pretest-posttest design was employed with 338 students exposed to the warning label proposed by the FDA and 328 students exposed to the label created by e-cigarette companies. Structural equation modeling analysis was implemented to examine the effect of warning labels with the analytical model grounded in the Theory of Planned Behavior. Findings showed that college students' perceived advantages of e-cigarette use were positively related to their intentions to use e-cigarettes, while perceived risks were negatively associated with their intentions. When comparing two labels, the governmental label was found to reduce college students' intentions to use e-cigarettes via increasing perceived risks of e-cigarette use (β=0.10, p<0.05), however, not via decreasing perceived advantages of e-cigarette use. The warning label currently used by e-cigarette companies showed no influence on beliefs about or intentions to use e-cigarettes. The warning label proposed by the FDA is more effective than that created by e-cigarette companies, however, has room for improvement to make a greater impact on e-cigarette use intention. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of preventive online mindfulness interventions on stress and mindfulness: A meta-analysis of randomized controlled trials.

PubMed

Jayewardene, Wasantha P; Lohrmann, David K; Erbe, Ryan G; Torabi, Mohammad R

2017-03-01

Empirical evidence suggested that mind-body interventions can be effectively delivered online. This study aimed to examine whether preventive online mindfulness interventions (POMI) for non-clinical populations improve short- and long-term outcomes for perceived-stress (primary) and mindfulness (secondary). Systematic search of four electronic databases, manuscript reference lists, and journal content lists was conducted in 2016, using 21 search-terms. Eight randomized controlled trials (RCTs) evaluating effects of POMI in non-clinical populations with adequately reported perceived-stress and mindfulness measures pre- and post-intervention were included. Random-effects models utilized for all effect-size estimations with meta-regression performed for mean age and %females. Participants were volunteers (adults; predominantly female) from academic, workplace, or community settings. Most interventions utilized simplified Mindfulness-Based Stress Reduction protocols over 2-12 week periods. Post-intervention, significant medium effect found for perceived-stress (g = 0.432), with moderate heterogeneity and significant, but small, effect size for mindfulness (g = 0.275) with low heterogeneity; highest effects were for middle-aged individuals. At follow-up, significant large effect found for perceived-stress (g = 0.699) with low heterogeneity and significant medium effect (g = 0.466) for mindfulness with high heterogeneity. No publication bias was found for perceived-stress; publication bias found for mindfulness outcomes led to underestimation of effects, not overestimation. Number of eligible RCTs was low with inadequate data reporting in some studies. POMI had substantial stress reduction effects and some mindfulness improvement effects. POMI can be a more convenient and cost-effective strategy, compared to traditional face-to-face interventions, especially in the context of busy, hard-to-reach, but digitally-accessible populations.

Stimulus Expectancy Modulates Inferior Frontal Gyrus and Premotor Cortex Activity in Auditory Perception

ERIC Educational Resources Information Center

Osnes, Berge; Hugdahl, Kenneth; Hjelmervik, Helene; Specht, Karsten

2012-01-01

In studies on auditory speech perception, participants are often asked to perform active tasks, e.g. decide whether the perceived sound is a speech sound or not. However, information about the stimulus, inherent in such tasks, may induce expectations that cause altered activations not only in the auditory cortex, but also in frontal areas such as…

Non-native fish introductions and the decline of the mountain yellow-legged frog from within protected areas

Treesearch

R.A. Knapp; K.R. Matthews

2000-01-01

Abstract: One of the most puzzling aspects of the worldwide decline of amphibians is their disappearance from within protected areas. Because these areas are ostensibly undisturbed, habitat alterations are generally perceived as unlikely causes. The introduction of non-native fishes into protected areas, however, is a common practice throughout the world and may exert...

Do Limited English Students Jeopardize the Education of Other Students? Lessons from the North Carolina Public School System

ERIC Educational Resources Information Center

Diette, Timothy M.; Uwaifo Oyelere, Ruth

2017-01-01

The significant increase in immigration has altered the ethnic composition of public schools in many states. Given the perceived negative impact of immigrant students by some, we are interested in investigating whether higher concentrations of students with limited English (LE) skills in a school affect the academic performance of native students.…

Metal Oxide Nanoparticles: The Importance of Size, Shape, Chemical Composition, and Valence State in Determining Toxicity

NASA Astrophysics Data System (ADS)

Dunnick, Katherine

Nanoparticles, which are defined as a structure with at least one dimension between 1 and 100 nm, have the potential to be used in a variety of consumer products due to their improved functionality compared to similar particles of larger size. Their small size is associated with increased strength, improved catalytic properties, and increased reactivity; however, their size is also associated with increased toxicity in vitro and in vivo. Numerous toxicological studies have been conducted to determine the properties of nanomaterials that increase their toxicity in order to manufacture new nanomaterials with decreased toxicity. Data indicates that size, shape, chemical composition, and valence state of nanomaterials can dramatically alter their toxicity profile. Therefore, the purpose of this dissertation was to determine how altering the shape, size, and chemical composition of various metal oxide nanoparticles would affect their toxicity. Metal oxides are used in variety of consumer products, from spray-sun screens, to food coloring agents; thus, understanding the toxicity of metal oxides and determining which aspects affect their toxicity may provide safe alternatives nanomaterials for continued use in manufacturing. Tungstate nanoparticles toxicity was assessed in an in vitro model using RAW 264.7 cells. The size, shape, and chemical composition of these nanomaterials were altered and the effect on reactive oxygen species and general cytotoxicity was determined using a variety of techniques. Results demonstrate that shape was important in reactive oxygen species production as wires were able to induce significant reactive oxygen species compared to spheres. Shape, size, and chemical composition did not have much effect on the overall toxicity of these nanoparticles in RAW 264.7 cells over a 72 hour time course, implicating that the base material of the nanoparticles was not toxic in these cells. To further assess how chemical composition can affect toxicity, cerium oxide nanoparticles were chemically modified using a process known as doping, to alter their valence state. The size and shape of the cerium oxide nanoparticles remained constant. Overall, results indicated that cerium oxide was not toxic in both RLE-6TN and NR8383 pulmonary rat cells, however, chemically modifying the valence state of the nanomaterial did affect the antioxidant potential. To determine if this trend was measureable in vivo, rats were exposed to various cerium oxide nanoparticles via intratracheal instillation and damage, changes in pulmonary cell differentials, and phagocytic cell activity were assessed. Results implicate that chemically modifying the nanoparticles had an effect on the overall damage induced by the material but did not dramatically affect inflammatory potential or phagocytic cell activity. Overall the data from these studies imply that size, shape, chemical composition, and valence state of nanomaterials can be manipulated to alter their toxicity.

McGurk illusion recalibrates subsequent auditory perception

PubMed Central

Lüttke, Claudia S.; Ekman, Matthias; van Gerven, Marcel A. J.; de Lange, Floris P.

2016-01-01

Visual information can alter auditory perception. This is clearly illustrated by the well-known McGurk illusion, where an auditory/aba/ and a visual /aga/ are merged to the percept of ‘ada’. It is less clear however whether such a change in perception may recalibrate subsequent perception. Here we asked whether the altered auditory perception due to the McGurk illusion affects subsequent auditory perception, i.e. whether this process of fusion may cause a recalibration of the auditory boundaries between phonemes. Participants categorized auditory and audiovisual speech stimuli as /aba/, /ada/ or /aga/ while activity patterns in their auditory cortices were recorded using fMRI. Interestingly, following a McGurk illusion, an auditory /aba/ was more often misperceived as ‘ada’. Furthermore, we observed a neural counterpart of this recalibration in the early auditory cortex. When the auditory input /aba/ was perceived as ‘ada’, activity patterns bore stronger resemblance to activity patterns elicited by /ada/ sounds than when they were correctly perceived as /aba/. Our results suggest that upon experiencing the McGurk illusion, the brain shifts the neural representation of an /aba/ sound towards /ada/, culminating in a recalibration in perception of subsequent auditory input. PMID:27611960

Food perceptions in terms of health among Norwegian-Pakistani women participating in a culturally adapted intervention.

PubMed

Råberg Kjøllesdal, Marte Karoline; Hjellset, Victoria Telle; Bjørge, Benedikte; Holmboe-Ottesen, Gerd; Wandel, Margareta

2011-10-01

To explore food perceptions in terms of health among Pakistani immigrant women, and if such perceptions could be altered through a culturally adapted intervention. The study is a culturally adapted lifestyle intervention aiming at reducing diabetes risk among Pakistani women, Oslo, Norway. There were 198 participants (25-62 years) recruited through a multi-recruitment strategy and randomly assigned into intervention and control groups. Data were collected through interviews with the help of a structured questionnaire with open-ended questions. Baseline data showed that many women emphasised vegetables (87%) and fish (52%) as important in a healthy diet, and perceived that the consumption of sugar (66%), oil (60%) and hard fat (39%) should be limited. After intervention, there was an increased proportion of women in the intervention group who perceived that consumption of sugar (p = 0.021) and white flour (p = 0.010) should be limited, in line with the emphasis of the intervention. Food perceptions in terms of health were generally in line with public dietary advice, however, with large variation among the women. A culturally adapted intervention had the potential to alter such perceptions.

Environmental Management in Small and Medium-Sized Companies: An Analysis from the Perspective of the Theory of Planned Behavior

PubMed Central

Sánchez-Medina, Agustín J.; Romero-Quintero, Leonardo; Sosa-Cabrera, Silvia

2014-01-01

In the business context, concern for the environment began to develop when pressure from the public administration and environmental awareness groups raised the specific requirements for companies. The Theory of Planned Behavior considers that people's conduct is determined by the intention of carrying out a certain behavior. Thus, the individual's intent is determined by three factors related to the desired outcome of the behavior: the Personal Attitude toward the Results, the Perceived Social Norms, and the Perceived Behavioral Control over the action. Therefore, the objectives of this paper are to clarify the attitudes of the managers of Canarian small and medium-sized companies about taking environmental measures, and try to demonstrate whether there is a relationship between the proposed factors and the intention to take these measures. PMID:24533094

Environmental management in small and medium-sized companies: an analysis from the perspective of the theory of planned behavior.

PubMed

Sánchez-Medina, Agustín J; Romero-Quintero, Leonardo; Sosa-Cabrera, Silvia

2014-01-01

In the business context, concern for the environment began to develop when pressure from the public administration and environmental awareness groups raised the specific requirements for companies. The Theory of Planned Behavior considers that people's conduct is determined by the intention of carrying out a certain behavior. Thus, the individual's intent is determined by three factors related to the desired outcome of the behavior: the Personal Attitude toward the Results, the Perceived Social Norms, and the Perceived Behavioral Control over the action. Therefore, the objectives of this paper are to clarify the attitudes of the managers of Canarian small and medium-sized companies about taking environmental measures, and try to demonstrate whether there is a relationship between the proposed factors and the intention to take these measures.

Enrichment options for African painted dogs (Lycaon pictus).

PubMed

Cloutier, Tammy L; Packard, Jane M

2014-01-01

Best practices for carnivore enrichment encourage the diversity of species-typical behaviors, increased activity, and reduced stereotypic behavior; ideally considering the life-history and behavior of each species. African wild dogs (Lycaon pictus), or painted dogs, are social carnivores that have large home ranges and complex pack dynamics (e.g., variation in group size, relatedness, etc.). As there are relatively few studies on painted dog enrichment, the goal of this study was to compile a list of enrichment options used by institutions participating in the species survival plan (SSP). Representatives were asked to describe social groups (n = 45), enclosures (n = 21), enrichment practices (options, delivery frequency, perceived success), and overall best practices. Respondents (61%, n = 23) reported using options for all six enrichment categories recommended by the Canid Taxon Advisory Group: environmental enrichment devices, habitat, sensory, food, behavioral, and social. Perceived success was significantly higher for the food category, followed by the sensory and behavioral categories. All respondents reported delivering enrichment at least multiple times a month, and most reported multiple times per week. Enclosure size did not differ significantly for mixed-sex groups (n = 28) compared to single-sex groups (n = 17). We discuss respondents' suggestions for best practices and the need to record data to compare perceived success with actual behavioral effects, controlling for variation in group size and composition. Overall, respondents recommended a flexible approach, since not all painted dogs and groups respond in the same way to the enrichment options. © 2014 Wiley Periodicals, Inc.

Temperature-dependency of Magnetic Susceptibility U Advantages and Limits For Magneto-mineralogical Studies

NASA Astrophysics Data System (ADS)

Kontny, A.

Low-field magnetic susceptibility measurements in the temperature range U192 to 700 C (k(T)) are a widely applied method used for the identification of magnetic phases and characteristic magnetic phase transitions. One of the advantages of this method is the precise determination of titanomagnetite composition independently from grain size. However, the interpretations of k(T)-curves often are discussed controversially because other effects like grain size or the occurrence of more than one magnetic phase complicate the courses. Case studies from the titanomagnetite and titanohe- matite solid solution series including pure magnetite and hematite will be presented and variations in chemical composition, alteration and grain size will be discussed in relation to their geological significance. (1) In subaerially extruded basaltic lava differences in the low-temperature legs of the k(T) curves indicate variations in the degree of high-temperature (deuteric) oxidation of titanomagnetite. This alteration to magnetite-rich titanomagnetite is accompanied by a grain size reduction, which can be correlated with the development of a susceptibility peak at about U160 C. Fur- ther oxidation transforms the titanomagnetite into titanohematite which again results in a characteristic k(T) behavior at low temperatures with a decrease in k with in- creasing temperature (2) Hydrothermal alteration from magnetite to hematite creates a hematite phase that cannot be seen in k(T)-curves. However, hematite that is grown in sediments, can be identified by its Tc. Therefore it is assumed that crystallinity of magnetic phases seems to play a significant role to explain a different behaviour. (3) Submarine basalts rapidly quenched from high temperatures often show wide anti- clines in the k(T)-curves which can be correlated with a range of chemical composition and grain sizes, including small amounts of pure magnetite. This feature is commonly attributed to low-temperature alteration of single domain grains of titanomagnetite and is described for ocean floor basalts. An alternative interpretation is given by composi- tional and grain size variations due to small scale fractionation of melt related to the cooling of the lava. Generally, the high-temperature leg of k(T) curves mostly indi- cates the chemical composition (Tc) and degree of alteration, the low-temperature leg seems to be more sensible for grain size variations.

The association between meaning of caregiving, perceived social support and level of depression of Taiwanese caregivers of mentally ill patients.

PubMed

Yen, Wen-Jiuan; Lundeen, Sally

2006-09-01

Caregiving is a demanding responsibility. Because of the de-institutionalization movement, much of the care provided by hospitals has been shifted to the community. Caregivers' issues cannot be overlooked. The purposes of the study are: (a) to understand meaning of caregiving, perceived social support and level of depression of caregivers during the transition phase immediately following a family members' discharge from the hospital to the community; (b) to determine the association between determinants and meaning of caregiving, perceived social support level of depression; (c) to determine the association between meaning of caregiving, perceived social support level of depression. Fifty five caregivers of schizophrenic patients were recruited from a private hospital in Taipei, Taiwan. Certain characteristics of caregivers were found to be associated with lower levels of depression, meaning of caregiving and perceived social support. Perceived social support was shown to be a mediator between the meaning of caregiving and caregivers' level of depression. Despite the small sample size, the findings can serve as a reference for mental health professionals as they develop mental health care program for patients and also for caregivers.

Does Pre-Cooling With Whole-Body Immersion Affect Thermal Sensation or Perceived Exertion?: A Critically-Appraised Topic.

PubMed

Wohlfert, Timothy M; Miller, Kevin C

2018-02-21

Clinical Scenario: Exertional heat stroke (EHS) is a potentially deadly heat illness and poses a significant health risk to athletes; EHS survival rates are near 100% if properly recognized and treated. 1 Whole body cold water immersion (CWI) is the most effective method of lowering body core temperature. 2 Precooling (PC) with CWI before exercise may prevent severe hyperthermia and/or EHS by increasing the body's overall heat-storage capacity. 3 However, PC may also alter athletes' perception of how hot they feel or how hard they are exercising. Consequently, they may be unable to accurately perceive their body core temperature or how hard they are working which may predispose them to severe hyperthermia or EHS. Does PC with whole-body CWI affect thermal sensation (TS) or rating of perceived exertion (RPE) during exercise in the heat? In four studies, 4-7 RPE during exercise ranged from 12 ± 2 to 20 ± 3 with no clinically meaningful differences between PC and control trials. Thermal sensation scores ranged from 2 ± 1 to 8 ± 0.5 in control trials and from 2 ± 1 to 7.5 ± 0.5 during PC trials. Clinical Bottom Line: Precooling did not cause clinically-meaningful differences in RPE or TS during exercise. It is unlikely PC would predispose athletes to EHS by altering perceptions of exercise intensity or body core temperature. Strength of Recommendation: None of the reviewed studies 4-7 (all level 2 studies with PEDro scores ≥5) suggest PC with CWI influences RPE or TS in exercising males.

Abnormal structure and functional connectivity of the anterior insula at pain-free periovulation is associated with perceived pain during menstruation.

PubMed

Dun, Wang-Huan; Yang, Jing; Yang, Ling; Ding, Dun; Ma, Xue-Ying; Liang, Feng-Li; von Deneen, Karen M; Ma, Shao-Hui; Xu, Xiao-Ling; Liu, Jixin; Zhang, Ming

2017-12-01

Neuroimaging studies have demonstrated the critical role of the insula in pain pathways and its close relation with the perceived intensity of nociceptive stimuli. We aimed to identify the structural and functional characteristics of the insula during periovulatory phase in women with primary dysmenorrhea (PDM), and further investigate its association with the intensity of perceived pain during menstruation. Optimized voxel-based morphometry and functional connectivity (FC) analyses were applied by using 3-dimensional T1-weighted and resting functional magnetic resonance imaging (fMRI) in 36 patients at the peri-ovulation phase and 29 age-, education-, and gender-matched healthy controls (HC). A visual analogue scale (VAS) was used to examine the intensity of the abdominal pain at periovulation and menstruation. In our results, PDM patients had significant higher VAS-rating during menstruaion than periovulation. Compared with the HC, PDM patients had lower gray matter density in the left anterior insula (aINS). Taken the left aINS as a seed region, we further found hypoconnectivity between aINS and medial prefrontal cortex (mPFC), which showed negative relation with the VAS during menstruation. As the aINS is a key site of the salience network (SN) and the mPFC is a critical region in the default mode network (DMN), it's implicated a trait-related central-alteration that communications between pain attention and perception networks were disrupted without the ongoing menstrual pain. Moreover, result of correlation analysis, at least in part, suggested a possible role of altered FC (pain-free period) in predicting pain perception (menstruation).

Neurosurgery Elective for Preclinical Medical Students: Early Exposure and Changing Attitudes.

PubMed

Zuckerman, Scott L; Mistry, Akshitkumar M; Hanif, Rimal; Chambless, Lola B; Neimat, Joseph S; Wellons, John C; Mocco, J; Sills, Allen K; McGirt, Matthew J; Thompson, Reid C

2016-02-01

Exposure to surgical subspecialties is limited during the preclinical years of medical school. To offset this limitation, the authors created a neurosurgery elective for first- and second-year medical students. The objective was to provide each student with early exposure to neurosurgery by combining clinical experience with faculty discussions about the academic and personal realities of a career in neurosurgery. From 2012 to 2013, the authors offered a neurosurgery elective course to first- and second-year medical students. Each class consisted of the following: 1) peer-reviewed article analysis; 2) student presentation; 3) faculty academic lecture; 4) faculty personal lecture with question and answer period. Thirty-five students were enrolled over a 2-year period. After completing the elective, students were more likely to: consider neurosurgery as a future career (P < 0.0001), perceive the personalities of attending physicians to be more collegial and friendly (P = 0.0002), perceive attending quality of life to be higher (P < 0.0001), and believe it was achievable to be a neurosurgeon and have a family (P < 0.0001). The elective did not alter students' perceived difficulty of training (P = 0.7105). The neurosurgery elective course significantly increased student knowledge across several areas and changed perceptions about collegiality, quality of life, and family-work balance, while not altering the students' views about the difficulty of training. Adopting a neurosurgery elective geared towards preclinical medical students can significantly change attitudes about the field of neurosurgery and has potential to increase interest in pursuing a career in neurosurgery. Copyright © 2016 Elsevier Inc. All rights reserved.

Does context matter in evaluations of stigmatized individuals? An fMRI study.

PubMed

Krendl, Anne C; Moran, Joseph M; Ambady, Nalini

2013-06-01

The manner in which disparate affective responses shape attitudes toward other individuals has received a great deal of attention in neuroscience research. However, the malleability of these affective responses remains largely unexplored. The perceived controllability of a stigma (whether or not the bearer of the stigma is perceived as being responsible for his or her condition) has been found to polarize behavioral affective responses to that stigma. The current study uses functional magnetic resonance imaging to identify the neural correlates underlying the evaluation of stigmatized individuals (people who are homeless) when perceptions of the controllability of their condition are altered. Results demonstrated that perceivers engaged neural networks implicated in inferring intentionality (e.g. the medial prefrontal cortex) when they evaluated a homeless individual who was described as being responsible for becoming homeless. Conversely, neural networks associated with resolving strong affective responses (e.g. insula) were engaged when evaluating a homeless individual who was described as not being responsible for becoming homeless.

Enduring consequences of terrorism: 7-month follow-up survey of reactions to the bombings in London on 7 July 2005.

PubMed

Rubin, G James; Brewin, Chris R; Greenberg, Neil; Hughes, Jamie Hacker; Simpson, John; Wessely, Simon

2007-04-01

Terrorist attacks can have psychological effects on the general public. To assess the medium-term effects of the July 2005 London bombings on the general population in London and to identify risk factors for persistent effects. We telephoned 1010 Londoners 11-13 days after the bombings to assess stress levels, perceived threat and travel intentions. Seven months later, 574 respondents were contacted again and asked similar questions, and questions concerning altered perceptions of self and the world. ;Substantial stress' (11%), perceived threat to self (43%) and reductions in travel because of the bombings (19%) persisted at a reduced level; other perceived threats remained unchanged. A more negative world view was common. Other than degree of exposure to the bombings, there were no consistent predictors of which people with short-term reactions would develop persistent reactions. A longer-term impact of terrorism on the perceptions and behaviour of Londoners was documented.

Perceived importance of employees' traits in the service industry.

PubMed

Lange, Rense; Houran, James

2009-04-01

Selection assessments are common practice to help reduce employee turnover in the service industry, but as too little is known about employees' characteristics, which are valued most highly by human resources professionals, a sample of 108 managers and human resources professionals rated the perceived importance of 31 performance traits for Line, Middle, and Senior employees. Rasch scaling analyses indicated strong consensus among the respondents. Nonsocial skills, abilities, and traits such as Ethical Awareness, Self-motivation, Writing Skills, Verbal Ability, Creativity, and Problem Solving were rated as more important for higher level employees. By contrast, traits which directly affect the interaction with customers and coworkers (Service Orientation, Communication Style, Agreeableness, Sense of Humor, Sensitivity to Diversity, Group Process, and Team Building) were rated as more important for lower level employees. Respondents' age and sex did not substantially alter these findings. Results are discussed in terms of improving industry professionals' perceived ecological and external validities of generic and customized assessments of employee.

Assessing the influence of lower facial profile convexity on perceived attractiveness in the orthognathic patient, clinician, and layperson.

PubMed

Naini, Farhad B; Donaldson, Ana Nora A; McDonald, Fraser; Cobourne, Martyn T

2012-09-01

The aim was a quantitative evaluation of how the severity of lower facial profile convexity influences perceived attractiveness. The lower facial profile of an idealized image was altered incrementally between 14° to -16°. Images were rated on a Likert scale by orthognathic patients, laypeople, and clinicians. Attractiveness ratings were greater for straight profiles in relation to convex/concave, with no significant difference between convex and concave profiles. Ratings decreased by 0.23 of a level for every degree increase in the convexity angle. Class II/III patients gave significantly reduced ratings of attractiveness and had greater desire for surgery than class I. A straight profile is perceived as most attractive and greater degrees of convexity or concavity deemed progressively less attractive, but a range of 10° to -12° may be deemed acceptable; beyond these values surgical correction is desired. Patients are most critical, and clinicians are more critical than laypeople. Copyright © 2012 Elsevier Inc. All rights reserved.

Neuroticism as Distancing: Perceptual Sources of Evidence

PubMed Central

Liu, Tianwei; Ode, Scott; Moeller, Sara K.; Robinson, Michael D.

2013-01-01

Several theories and self-reported sources of data link individual differences in negative affectivity to avoidance motivation. Chronic avoidance motivation, through repeated practice, may result in a relatively cognitive distance-enhancing dynamic whereby events and stimuli are perceived as further away from the self, even when they are not threatening. Such predictions are novel, but follow from cybernetic theories of self-regulation. In five studies (total N = 463), relations of this type were investigated. Study 1 presented participants with phrases that were ambiguous and found that trait negative affect predicted phrase interpretation in a distance-enhancing temporal direction. Study 2 replicated this effect across a systematic manipulation of event valence. Study 3 asked individuals to estimate the size of words and found that individuals higher in neuroticism generally perceived words to be smaller than did individuals lower in neuroticism. In Study 4, people high (but not low) in neuroticism perceived words to be shrinking faster than they were growing. In Study 5, greater perceptual distancing, in a font size estimation task, predicted more adverse reactions to negative events in daily life. Although normative effects varied across studies, consistent support for a chronic distancing perspective of individual differences in negative affectivity was found. PMID:23527850

Replicating and extending Bourdon's (1902) experiment on motion parallax.

PubMed

Ono, Hiroshi; Lillakas, Linda; Kapoor, Anjani; Wong, Irene

2013-01-01

Bourdon conducted the first laboratory experiment on observer-produced motion parallax as a cue to depth. In three experiments, we replicated and extended Bourdon's experiment. In experiment 1, we reproduced his finding: when the two cues, motion parallax and relative height, were combined, accuracy of depth perception was high, and when the two cues were in conflict, accuracy was lower. In experiment 2, the relative height cue was replaced with relative retinal image size. As in experiment 1, when the two cues (motion parallax and relative retinal image size) were combined, accuracy was high, but when they were in conflict, it was lower. In experiment 3, the stimuli from experiments 1 and 2 were viewed monocularly with head movement and binocularly without head movement. In the binocular conditions, accuracy, certainty, and the extent of perceived depth were higher than in the monocular condition. In the conflict conditions, accuracy, certainty, and the extent of perceived depth were lower than in the no-conflict condition, but the extent of perceived motion was larger. These results are discussed in terms of recent findings about the effectiveness of motion parallax as a cue for depth.

Exploring the feasibility of traditional image querying tasks for industrial radiographs

NASA Astrophysics Data System (ADS)

Bray, Iliana E.; Tsai, Stephany J.; Jimenez, Edward S.

2015-08-01

Although there have been great strides in object recognition with optical images (photographs), there has been comparatively little research into object recognition for X-ray radiographs. Our exploratory work contributes to this area by creating an object recognition system designed to recognize components from a related database of radiographs. Object recognition for radiographs must be approached differently than for optical images, because radiographs have much less color-based information to distinguish objects, and they exhibit transmission overlap that alters perceived object shapes. The dataset used in this work contained more than 55,000 intermixed radiographs and photographs, all in a compressed JPEG form and with multiple ways of describing pixel information. For this work, a robust and efficient system is needed to combat problems presented by properties of the X-ray imaging modality, the large size of the given database, and the quality of the images contained in said database. We have explored various pre-processing techniques to clean the cluttered and low-quality images in the database, and we have developed our object recognition system by combining multiple object detection and feature extraction methods. We present the preliminary results of the still-evolving hybrid object recognition system.

Effects of spaceflight (STS-87) on tropisms and plastid positioning in protonemata of the moss Ceratodon purpureus

NASA Astrophysics Data System (ADS)

Kern, V. D.; Sack, F. D.

Apical cells of moss protonemata represent a single-celled system that perceives and reacts to light (positive and negative phototropism) and to gravity (negative gravitropism). Phototropism completely overrides gravitropism when apical cells are laterally irradiated with relatively high red light intensities, but below a defined light intensity threshold gravitropism competes with the phototropic reaction. A 16 day-long exposure to microgravity conditions demonstrated that gravitropism is allowed when protonemata are laterally illuminated with light intensities below 140 nmol m-2s-1. Protonemata that were grown in darkness in microgravity expressed an endogenous tendency to grow in arcs so that the overall culture morphology resembled a clockwise spiral. However this phenomenon only was observed in cultures that had reached a critical age and/or size. Organelle positioning in dark-grown apical cells was significantly altered in microgravity. Gravisensing most likely involves the sedimentation of starch-filled amyloplasts in a well-defined area of the tip cell. Amyloplasts that at 1-g are sedimented were clustered at the apical part of the sedimentation zone in microgravity. Clustering observed in microgravity or during clino-rotation significantly differs from sedimentation-induced plastid aggregations after inversion of tip cells at 1-g.

Method to study cell migration under uniaxial compression

PubMed Central

Srivastava, Nishit; Kay, Robert R.; Kabla, Alexandre J.

2017-01-01

The chemical, physical, and mechanical properties of the extracellular environment have a strong effect on cell migration. Aspects such as pore size or stiffness of the matrix influence the selection of the mechanism used by cells to propel themselves, including by pseudopods or blebbing. How a cell perceives its environment and how such a cue triggers a change in behavior are largely unknown, but mechanics is likely to be involved. Because mechanical conditions are often controlled by modifying the composition of the environment, separating chemical and physical contributions is difficult and requires multiple controls. Here we propose a simple method to impose a mechanical compression on individual cells without altering the composition of the matrix. Live imaging during compression provides accurate information about the cell's morphology and migratory phenotype. Using Dictyostelium as a model, we observe that a compression of the order of 500 Pa flattens the cells under gel by up to 50%. This uniaxial compression directly triggers a transition in the mode of migration from primarily pseudopodial to bleb driven in <30 s. This novel device is therefore capable of influencing cell migration in real time and offers a convenient approach with which to systematically study mechanotransduction in confined environments. PMID:28122819

Sleep quality during exam stress: the role of alcohol, caffeine and nicotine.

PubMed

Zunhammer, Matthias; Eichhammer, Peter; Busch, Volker

2014-01-01

Academic exam stress is known to compromise sleep quality and alter drug consumption in university students. Here we evaluated if sleeping problems and changes in legal drug consumption during exam stress are interrelated. We used the Pittsburgh Sleep Quality Index (PSQI) to survey sleep quality before, during, and after an academic exam period in 150 university students in a longitudinal questionnaire study. Self-reports of alcohol, caffeine, and nicotine consumption were obtained. The Perceived Stress Questionnaire (PSQ-20) was used as a measure of stress. Sleep quality and alcohol consumption significantly decreased, while perceived stress and caffeine consumption significantly increased during the exam period. No significant change in nicotine consumption was observed. In particular, students shortened their time in bed and showed symptoms of insomnia. Mixed model analysis indicated that sex, age, health status, as well as the amounts of alcohol and caffeine consumed had no significant influence on global sleep quality. The amount of nicotine consumed and perceived stress were identified as significant predictors of diminished sleep quality. Nicotine consumption had a small-to-very-small effect on sleep quality; perceived stress had a small-to-moderate effect. In conclusion, diminished sleep quality during exam periods was mainly predicted by perceived stress, while legal drug consumption played a minor role. Exam periods may pose an interesting model for the study of stress-induced sleeping problems and their mechanisms.

Sleep Quality during Exam Stress: The Role of Alcohol, Caffeine and Nicotine

PubMed Central

Zunhammer, Matthias; Eichhammer, Peter; Busch, Volker

2014-01-01

Academic exam stress is known to compromise sleep quality and alter drug consumption in university students. Here we evaluated if sleeping problems and changes in legal drug consumption during exam stress are interrelated. We used the Pittsburgh Sleep Quality Index (PSQI) to survey sleep quality before, during, and after an academic exam period in 150 university students in a longitudinal questionnaire study. Self-reports of alcohol, caffeine, and nicotine consumption were obtained. The Perceived Stress Questionnaire (PSQ-20) was used as a measure of stress. Sleep quality and alcohol consumption significantly decreased, while perceived stress and caffeine consumption significantly increased during the exam period. No significant change in nicotine consumption was observed. In particular, students shortened their time in bed and showed symptoms of insomnia. Mixed model analysis indicated that sex, age, health status, as well as the amounts of alcohol and caffeine consumed had no significant influence on global sleep quality. The amount of nicotine consumed and perceived stress were identified as significant predictors of diminished sleep quality. Nicotine consumption had a small-to-very-small effect on sleep quality; perceived stress had a small-to-moderate effect. In conclusion, diminished sleep quality during exam periods was mainly predicted by perceived stress, while legal drug consumption played a minor role. Exam periods may pose an interesting model for the study of stress-induced sleeping problems and their mechanisms. PMID:25279939

A comparison of workplace safety perceptions among financial decision-makers of medium- vs. large-size companies.

PubMed

Huang, Yueng-Hsiang; Leamon, Tom B; Courtney, Theodore K; Chen, Peter Y; DeArmond, Sarah

2011-01-01

This study, through a random national survey in the U.S., explored how corporate financial decision-makers perceive important workplace safety issues as a function of the size of the company for which they worked (medium- vs. large-size companies). Telephone surveys were conducted with 404 U.S. corporate financial decision-makers: 203 from medium-size companies and 201 from large companies. Results showed that the patterns of responding for participants from medium- and large-size companies were somewhat similar. The top-rated safety priorities in resource allocation reported by participants from both groups were overexertion, repetitive motion, and bodily reaction. They believed that there were direct and indirect costs associated with workplace injuries and for every dollar spent improving workplace safety, more than four dollars would be returned. They perceived the top benefits of an effective safety program to be predominately financial in nature - increased productivity and reduced costs - and the safety modification participants mentioned most often was to have more/better safety-focused training. However, more participants from large- than medium-size companies reported that "falling on the same level" was the major cause of workers' compensation loss, which is in line with industry loss data. Participants from large companies were more likely to see their safety programs as better than those of other companies in their industries, and those of medium-size companies were more likely to mention that there were no improvements needed for their companies. Copyright © 2009 Elsevier Ltd. All rights reserved.

Ergonomic approaches to designing educational materials for immersive multi-projection system

NASA Astrophysics Data System (ADS)

Shibata, Takashi; Lee, JaeLin; Inoue, Tetsuri

2014-02-01

Rapid advances in computer and display technologies have made it possible to present high quality virtual reality (VR) environment. To use such virtual environments effectively, research should be performed into how users perceive and react to virtual environment in view of particular human factors. We created a VR simulation of sea fish for science education, and we conducted an experiment to examine how observers perceive the size and depth of an object within their reach and evaluated their visual fatigue. We chose a multi-projection system for presenting the educational VR simulation, because this system can provide actual-size objects and produce stereo images located close to the observer. The results of the experiment show that estimation of size and depth was relatively accurate when subjects used physical actions to assess them. Presenting images within the observer's reach is suggested to be useful for education in VR environment. Evaluation of visual fatigue shows that the level of symptoms from viewing stereo images with a large disparity in VR environment was low in a short time.

"Skinny is prettier and normal: I want to be normal"-Perceived body image of non-Western ethnic minority children in the Netherlands.

PubMed

Veldhuis, Jolanda; Te Poel, Fam; Pepping, Rian; Konijn, Elly A; Spekman, Marloes L C

2017-03-01

While the prevalence of overweight and obesity is higher among children of some non-Western ethnic minorities than among their Caucasian counterparts, their body image is understudied. The current study examined the body image of Dutch children of non-Western ethnic minorities (i.e., Surinamese, Antillean, Moroccan, and Turkish). Sociocultural influences from school, media and home environments and their perceptions of overweight prevention programs were taken into account. Fifty-two non-Western ethnic minority children (aged 8-12 years) participated in semi-structured interviews and focus groups. Results showed that the children generally underestimated their current body size, which was often overweight, and preferred thin and 'normal' body sizes. Results further revealed important insights into culturally determined themes, relating to perceived preferences in media, peers, parents, and teachers, nutritional habits, and children's beliefs about school-based health interventions. We conclude that targeting culturally sensitive awareness about actual body size and healthy body images seems paramount in future interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Effects of Varying Electronic Cigarette Warning Label Design Features On Attention, Recall, and Product Perceptions Among Young Adults.

PubMed

Mays, Darren; Villanti, Andrea; Niaura, Raymond S; Lindblom, Eric N; Strasser, Andrew A

2017-12-13

This study was a 3 (Brand: Blu, MarkTen, Vuse) by 3 (Warning Size: 20%, 30%, or 50% of advertisement surface) by 2 (Warning Background: White, Red) experimental investigation of the effects of electronic cigarette (e-cigarette) warning label design features. Young adults aged 18-30 years (n = 544) were recruited online, completed demographic and tobacco use history measures, and randomized to view e-cigarette advertisements with warning labels that varied by the experimental conditions. Participants completed a task assessing self-reported visual attention to advertisements with a-priori regions of interest defined around warning labels. Warning message recall and perceived addictiveness of e-cigarettes were assessed post-exposure. Approximately half of participants reported attending to warning labels and reported attention was greater for warnings on red versus white backgrounds. Recall of the warning message content was also greater among those reporting attention to the warning label. Overall, those who viewed warnings on red backgrounds reported lower perceived addictiveness than those who viewed warnings on white backgrounds, and e-cigarette users reported lower perceived addictiveness than non-users. Among e-cigarette users, viewing warnings on white backgrounds produced perceptions more similar to non-users. Greater recall was significantly correlated with greater perceived addictiveness. This study provides some of the first evidence that e-cigarette warning label design features including size and coloring affect self-reported attention and content recall.

A Negative Revelation.

ERIC Educational Resources Information Center

Hillis, R. K.

1982-01-01

Describes how teaching secondary art students to perceive negative shape improved their drawings of a bicycle, a visually complex mechanical structure. Concentrating on negative shape forces students to work with the relationships between shapes and their relative sizes. (AM)

Managerial Receptivity and Implementation of Policies.

ERIC Educational Resources Information Center

Stevens, John M.; And Others

1980-01-01

Managerial receptivity to new policy, perceived emphasis by top level management, organizational size, work overload, perceptions of the importance of performance for promotion, and the manager's attitude toward change were important predictors for successful implementation. (Author)

Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study

PubMed Central

Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Wylie, Kevan; Muir, Gordon

2015-01-01

Introduction Little is known about the sexual functioning and behavior of men anxious about the size of their penis and the means that they might use to try to alter the size of their penis. Aim To compare sexual functioning and behavior in men with body dysmorphic disorder (BDD) concerning penis size and in men with small penis anxiety (SPA without BDD) and in a control group of men who do not have any concerns. Methods An opportunistic sample of 90 men from the community were recruited and divided into three groups: BDD (n = 26); SPA (n = 31) and controls (n = 33). Main Outcome Measures The Index of Erectile Function (IEF), sexual identity and history; and interventions to alter the size of their penis. Results Men with BDD compared with controls had reduced erectile dysfunction, orgasmic function, intercourse satisfaction and overall satisfaction on the IEF. Men with SPA compared with controls had reduced intercourse satisfaction. There were no differences in sexual desire, the frequency of intercourse or masturbation across any of the three groups. Men with BDD and SPA were more likely than the controls to attempt to alter the shape or size of their penis (for example jelqing, vacuum pumps or stretching devices) with poor reported success. Conclusion Men with BDD are more likely to have erectile dysfunction and less satisfaction with intercourse than controls but maintain their libido. Further research is required to develop and evaluate a psychological intervention for such men with adequate outcome measures. PMID:26468378

Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study.

PubMed

Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Wylie, Kevan; Muir, Gordon

2015-09-01

Little is known about the sexual functioning and behavior of men anxious about the size of their penis and the means that they might use to try to alter the size of their penis. To compare sexual functioning and behavior in men with body dysmorphic disorder (BDD) concerning penis size and in men with small penis anxiety (SPA without BDD) and in a control group of men who do not have any concerns. An opportunistic sample of 90 men from the community were recruited and divided into three groups: BDD (n = 26); SPA (n = 31) and controls (n = 33). The Index of Erectile Function (IEF), sexual identity and history; and interventions to alter the size of their penis. Men with BDD compared with controls had reduced erectile dysfunction, orgasmic function, intercourse satisfaction and overall satisfaction on the IEF. Men with SPA compared with controls had reduced intercourse satisfaction. There were no differences in sexual desire, the frequency of intercourse or masturbation across any of the three groups. Men with BDD and SPA were more likely than the controls to attempt to alter the shape or size of their penis (for example jelqing, vacuum pumps or stretching devices) with poor reported success. Men with BDD are more likely to have erectile dysfunction and less satisfaction with intercourse than controls but maintain their libido. Further research is required to develop and evaluate a psychological intervention for such men with adequate outcome measures.

Depression among Transgender Older adults: General and Minority Stress

PubMed Central

Hoy-Ellis, Charles P.; Fredriksen-Goldsen, Karen I.

2017-01-01

Objectives This study aims to (1) examine the direct and indirect effects internalized heterosexism, concealment of gender identity, and perceived general stress in association with depression among transgender older adults; and (2) to assess the relative contribution of each relationship. Methods Secondary analyses of data from a large community-based study of older sexual and gender minorities were conducted utilizing structural equation modeling with a subsample (n = 174) of transgender adults aged 50 to 86-years old. Results Disclosure of gender identity had no significant direct or indirect effects on either perceived general stress or depression. Internalized heterosexism did not have a direct effect on depression, but did have a significant indirect effect through perceived general stress. Finally, perceived general stress had an additional significant direct effect on depression, over and above internalized heterosexism. Total effect sizes appear to be considerable with standardized betas greater than 5.0. Conclusion Perceived general stress and internalized heterosexism independently and cumulatively have significant direct and indirect effects on depression among transgender older adults. Implications for depression among transgender older adults and the role of community psychology are discussed. PMID:28369987

Metro passengers’ route choice model and its application considering perceived transfer threshold

PubMed Central

Jin, Fanglei; Zhang, Yongsheng; Liu, Shasha

2017-01-01

With the rapid development of the Metro network in China, the greatly increased route alternatives make passengers’ route choice behavior and passenger flow assignment more complicated, which presents challenges to the operation management. In this paper, a path sized logit model is adopted to analyze passengers’ route choice preferences considering such parameters as in-vehicle time, number of transfers, and transfer time. Moreover, the “perceived transfer threshold” is defined and included in the utility function to reflect the penalty difference caused by transfer time on passengers’ perceived utility under various numbers of transfers. Next, based on the revealed preference data collected in the Guangzhou Metro, the proposed model is calibrated. The appropriate perceived transfer threshold value and the route choice preferences are analyzed. Finally, the model is applied to a personalized route planning case to demonstrate the engineering practicability of route choice behavior analysis. The results show that the introduction of the perceived transfer threshold is helpful to improve the model’s explanatory abilities. In addition, personalized route planning based on route choice preferences can meet passengers’ diversified travel demands. PMID:28957376

Perceived effects of attending physician workload in academic medical intensive care units: a national survey of training program directors.

PubMed

Ward, Nicholas S; Read, Richard; Afessa, Bekele; Kahn, Jeremy M

2012-02-01

Increases in the size and number of American intensive care units have not been accompanied by a comparable increase in the critical care physician workforce, raising concerns that intensivists are becoming overburdened by workload. This is especially concerning in academic intensive care units where attending physicians must couple teaching duties with patient care. We performed an in-person and electronic survey of the membership of the Association of Pulmonary and Critical Care Medicine Program Directors, soliciting information about patient workload, other hospital and medical education duties, and perceptions of the workplace and teaching environment of their intensive care units. Eighty-four out of a total 121 possible responses were received from program directors or their delegates, resulting in a response rate of 69%. The average daily (SD) census (as perceived by the respondents) was 18.8 ± 8.9 patients, and average (SD) maximum service size recalled was 24.1 ± 9.9 patients. Twenty-seven percent reported no policy setting an upper limit for the daily census. Twenty-eight percent of respondents felt the average census was "too many" and 71% felt the maximum size was "too many." The median (interquartile range) patient-to-attending physician ratio was 13 (10-16). When categorized according to this median, respondents from intensive care units with high patient/physician ratios (n = 31) perceived significantly more time constraints, more stress, and difficulties with teaching trainees than respondents with low patient/physician ratios (n = 40). The total number of non-nursing healthcare workers per patient was similar in both groups, suggesting that having more nonattending physician staff does not alleviate perceptions of overwork and stress in the attending physician. Academic intensive care unit physicians that direct fellowship programs frequently perceived being overburdened in the intensive care unit. Understaffing intensive care units with attending physicians may have a negative impact on teaching, patient care, and workforce stability.

Use of the electrosurgical unit in a carbon dioxide atmosphere.

PubMed

Culp, William C; Kimbrough, Bradly A; Luna, Sarah; Maguddayao, Aris J; Eidson, Jack L; Paolino, David V

2016-01-01

The electrosurgical unit (ESU) utilizes an electrical discharge to cut and coagulate tissue and is often held above the surgical site, causing a spark to form. The voltage at which the spark is created, termed the breakdown voltage, is governed by the surrounding gaseous environment. Surgeons are now utilizing the ESU laparoscopically with carbon dioxide insufflation, potentially altering ESU operating characteristics. This study examines the clinical implications of altering gas composition by measuring the spark gap distance as a marker of breakdown voltage and use of the ESU on a biologic model, both in room air and carbon dioxide. Paschen's Law predicted a 35% decrease in gap distance in carbon dioxide, while testing revealed an average drop of 37-47% as compared to air. However, surgical model testing revealed no perceivable clinical difference. Electrosurgery can be performed in carbon dioxide environments, although surgeons should be aware of potentially altered ESU performance.

Nuclear size is sensitive to NTF2 protein levels in a manner dependent on Ran binding.

PubMed

Vuković, Lidija D; Jevtić, Predrag; Zhang, Zhaojie; Stohr, Bradley A; Levy, Daniel L

2016-03-15

Altered nuclear size is associated with many cancers, and determining whether cancer-associated changes in nuclear size contribute to carcinogenesis necessitates an understanding of mechanisms of nuclear size regulation. Although nuclear import rates generally positively correlate with nuclear size, NTF2 levels negatively affect nuclear size, despite the role of NTF2 (also known as NUTF2) in nuclear recycling of the import factor Ran. We show that binding of Ran to NTF2 is required for NTF2 to inhibit nuclear expansion and import of large cargo molecules in Xenopus laevis egg and embryo extracts, consistent with our observation that NTF2 reduces the diameter of the nuclear pore complex (NPC) in a Ran-binding-dependent manner. Furthermore, we demonstrate that ectopic NTF2 expression in Xenopus embryos and mammalian tissue culture cells alters nuclear size. Finally, we show that increases in nuclear size during melanoma progression correlate with reduced NTF2 expression, and increasing NTF2 levels in melanoma cells is sufficient to reduce nuclear size. These results show a conserved capacity for NTF2 to impact on nuclear size, and we propose that NTF2 might be a new cancer biomarker. © 2016. Published by The Company of Biologists Ltd.

The effects of perceived quality on the behavioural economics of alcohol, amphetamine, cannabis, cocaine, and ecstasy purchases.

PubMed

Cole, Jon C; Goudie, Andrew J; Field, Matt; Loverseed, Anne-Claire; Charlton, Sarah; Sumnall, Harry R

2008-04-01

Previous research has indicated that non-dependent polydrug users are willing to pay more money to buy good quality drugs as their income increased. This study sought to examine whether altering the perceived quality of controlled drugs would affect drug purchases if the monetary price remained fixed. A random sample of 80 polydrug users were recruited. All participants were administered an anonymous questionnaire consisting of the Drug Abuse Screening Test for Adolescents (DAST-A), the Severity of Dependence Scale for cannabis (SDS), the Alcohol Use Disorders Identification Test (AUDIT), the Hospital Anxiety and Depression Scale (HADS), and questions about their drug use. Participants then completed a simulation of controlled drug purchases where the price of alcohol, amphetamine, cannabis, cocaine, and ecstasy remained the same but their perceived quality changed (i.e. unit price increased as the perceived quality decreased). The demand for alcohol was quality inelastic and alcohol quality had no effects on the purchase of any other controlled drug. Demand for cannabis was quality elastic and alcohol substituted for cannabis as its unit price increased. Demand for cocaine was quality elastic and alcohol, cannabis, and ecstasy substituted for cocaine as its unit price increased. Demand for ecstasy was quality elastic and alcohol and cocaine both substituted for ecstasy as its unit price increased. These results suggest that perceived quality influences the demand for controlled drugs and that monitoring the perceived quality of controlled drugs may provide a warning of potential public health problems in the near future.

The evolutionary legacy of size-selective harvesting extends from genes to populations

PubMed Central

Uusi-Heikkilä, Silva; Whiteley, Andrew R; Kuparinen, Anna; Matsumura, Shuichi; Venturelli, Paul A; Wolter, Christian; Slate, Jon; Primmer, Craig R; Meinelt, Thomas; Killen, Shaun S; Bierbach, David; Polverino, Giovanni; Ludwig, Arne; Arlinghaus, Robert

2015-01-01

Size-selective harvesting is assumed to alter life histories of exploited fish populations, thereby negatively affecting population productivity, recovery, and yield. However, demonstrating that fisheries-induced phenotypic changes in the wild are at least partly genetically determined has proved notoriously difficult. Moreover, the population-level consequences of fisheries-induced evolution are still being controversially discussed. Using an experimental approach, we found that five generations of size-selective harvesting altered the life histories and behavior, but not the metabolic rate, of wild-origin zebrafish (Danio rerio). Fish adapted to high positively size selective fishing pressure invested more in reproduction, reached a smaller adult body size, and were less explorative and bold. Phenotypic changes seemed subtle but were accompanied by genetic changes in functional loci. Thus, our results provided unambiguous evidence for rapid, harvest-induced phenotypic and evolutionary change when harvesting is intensive and size selective. According to a life-history model, the observed life-history changes elevated population growth rate in harvested conditions, but slowed population recovery under a simulated moratorium. Hence, the evolutionary legacy of size-selective harvesting includes populations that are productive under exploited conditions, but selectively disadvantaged to cope with natural selection pressures that often favor large body size. PMID:26136825

Web-enabled Exercise Generation Tool for Battle Command Training

DTIC Science & Technology

2010-08-01

perceived as fair. Some non-instructional bells and whistles, such as background music and two-dimensional animation, should be judiciously...modify the current image by changing its size or adding a caption (Figure 12). Second, the trainer can upload a new image from his/her computer and...specify properties such as size, caption , image credit, and whether the image is searchable and usable by other trainers (Figure 13). Finally, the

[Relationships between well-being and social support: a meta analysis of studies conducted in Turkey].

PubMed

Yalçın, İlhan

2015-01-01

The purpose of this study was to investigate overall relationships between well-being and social support through meta-analysis. Studies which investigated associations between social support and life satisfaction, subjective well-being, self-esteem, depression, loneliness were included in the meta-analysis. By doing literature review to assess studies for potential inclusion; studies were included which met the inclusion criteria. Inclusion criteria were that studies must be conducted in Turkey and must report a correlation coefficient between study variables. Data were analyzed using a random effect model. It was found that there was a positive relationship between overall well-being and social support; level of social support was negatively correlated with depression and loneliness. For well-being variables, the mean effect size of perceived support from family and for depression/loneliness, the mean effect size of perceived support from friends were significantly stronger than other support sources. For both well-being variables and depression/loneliness variables, mean effect size of studies conducted with older people was significantly stronger than studies conducted with other age groups. Also, mean effect size of theses were significantly stronger than articles. The findings are expected to contribute to a better understanding of relationships between social support and well-being.

Forest fuel reduction alters fire severity and long-term carbon storage in three Pacific Northwest ecosystems

Treesearch

Stephen R. Mitchell; Mark E. Harmon; Kari E.B. O' Connell

2009-01-01

Two forest management objectives being debated in the context of federally managed landscapes in the U.S. Pacific Northwest involve a perceived trade-off between fire restoration and carbon sequestration. The former strategy would reduce fuel (and therefore carbon [C]) that has accumulated through a century of fire suppression and exclusion which has led to extreme...

Perceived Social Support and Markers of Heart Failure Severity

DTIC Science & Technology

2011-09-09

necessary for altering threat evaluation and enhancing self - esteem . Informational support, also referred to as appraisal support, describes the availability...1994). Social connections have been shown to enhance mood, reinforce self - esteem , and introduce adaptive coping resources for stress (Spiegel, Bloom...6MWT), self -reported symptoms as indicated by the Kansas City Cardiomyopathy Questionnaire (KCCQ), and levels of the biomarker BNP). Methods. Ninety

Mountain birdwatch: developing a coordinated monitoring program for high-elevation birds in the Atlantic northern forest

Treesearch

John D. Lloyd; Julie Hart; J. Dan Lambert

2010-01-01

Birds occupying high-elevation forests in the northeast are perceived to be at risk from a variety of external forces, most notably the potential loss and alteration of habitat associated with global climate change and the increased deployment of wind-energy facilities. However, the Breeding Bird Survey (BBS), a standardized national monitoring scheme widely used to...

The Republic of Singapore: Informed Questions

DTIC Science & Technology

2003-01-01

Singaporean society has, until recently, exhibited a high degree of tolerance and social cohesion .7 Yet Singapore exists as a conspicuously wealthy...immigrants threatens to alter Singapore’s ethnic composition and thus undermine the social cohesion upon which the country’s stability and...bold measures in response to perceived threats to the nation’s prized social cohesion . In March 2001, the government initiated high-level dialog

Perceived stigma and associated factors among people with epilepsy at Gondar University Hospital, Northwest Ethiopia: a cross-sectional institution based study.

PubMed

Bifftu, Berhanu Boru; Dachew, Berihun Assefa; Tiruneh, Bewket Tadesse

2015-12-01

Epilepsy is the world's most common neurological disorder, affecting approximately 69 million people worldwide. Perceived stigma affects many domains of the lives of people with epilepsy. However, in Ethiopia there is dearth of study on perceived stigma specifically among people with epilepsy. To assess the prevalence of perceived stigma and associated factors among people with epilepsy (PWE) attending the outpatient department of the University of Gondar hospital, Northwest Ethiopia, 2014. Institution based quantitative cross - sectional study was employed among 408 individuals people with epilepsy. Single population proportion formula was used utilized to calculate sample size. The participants were selected using systematic random sampling technique. Perceived stigma was measured using by the modified Family Interview Schedule (FIS) tool. Binary logistic regression analysis and adjusted odds ratio with 95% confidence interval were used to identify the associated factors with perceived stigma.. Overall, the prevalence of perceived stigma was found to be 71.6%. Marital status [single (AOR = 0.23, CI: 0.25, 0.90), widowed ( AOR = 0.37, CI: 0.15, 0.90) duration of illness [2-5 years (AOR = 4.38, CI:1.98,9.62, 6-10 years (AOR =4.29, CI:1.90,9.64, ≥11 years (AOR = 4.31,CI:1.84,10.00) and seizure frequency of [1-11per year (AOR=2.34, CI:2.21,3.56), ≥1per month (AOR = 5.63, CI:3.42,10.32)] were factors associated with perceived stigma. Overall, the prevalence of perceived stigma was found to be high. Marital status, long duration of illness and seizure frequency were factors associated with perceived stigma.

Perceived value in food selection when dining out: comparison of African Americans and Euro-Americans.

PubMed

Vinci, Debra M; Philipp, Steven F

2007-06-01

This descriptive study compares African Americans' and Euro-Americans' perceived value of food selection pertaining to cost, portion size, and meal satisfaction when eating away from home. A stratified sample was drawn from a southern U.S. metropolitan area (N= 1,011; 486 African American, 525 Euro-American). Analysis showed no difference between African-American and Euro-American adults by sex or how often they dined out. These two groups significantly differed across years of education, age, and answering 14 of 18 rated statements on value perceptions. African-Americans' value perceptions were influenced more by lower cost foods and larger portion sizes than those of Euro-Americans. For meal satisfaction, African Americans were more likely to agree with statements that indicate preferring foods high in energy and low in essential micronutrient density. This study supports the need for more investigation.

The size-weight illusion induced through human echolocation.

PubMed

Buckingham, Gavin; Milne, Jennifer L; Byrne, Caitlin M; Goodale, Melvyn A

2015-02-01

Certain blind individuals have learned to interpret the echoes of self-generated sounds to perceive the structure of objects in their environment. The current work examined how far the influence of this unique form of sensory substitution extends by testing whether echolocation-induced representations of object size could influence weight perception. A small group of echolocation experts made tongue clicks or finger snaps toward cubes of varying sizes and weights before lifting them. These echolocators experienced a robust size-weight illusion. This experiment provides the first demonstration of a sensory substitution technique whereby the substituted sense influences the conscious perception through an intact sense. © The Author(s) 2014.

A simple photometric factor in perceived depth order of bistable transparency patterns.

PubMed

Fukiage, Taiki; Oishi, Takeshi; Ikeuchi, Katsushi

2014-05-05

Previous studies on perceptual transparency defined the photometric condition in which perceived depth ordering between two surfaces becomes ambiguous. Even under this bistable transparency condition, it is known that depth-order perceptions are often biased toward one specific interpretation (Beck, Prazdny, & Ivry, 1984; Delogu, Fedorov, Belardinelli, & van Leeuwen, 2010; Kitaoka, 2005; Oyama & Nakahara, 1960). In this study, we examined what determines the perceived depth ordering for bistable transparency patterns using stimuli that simulated two partially overlapping disks resulting in four regions: a (background), b (portion of right disk), p (portion of left disk), and q (shared region). In contrast to the previous theory that proposed contributions of contrast against the background region (i.e., contrast at contour b/a and contrast at contour p/a) to perceived depth order in bistable transparency patterns, the present study demonstrated that contrast against the background region has little influence on perceived depth order compared with contrast against the shared region (i.e., contrast at contour b/q and contrast at contour p/q). In addition, we found that the perceived depth ordering is well predicted by a simpler model that takes into consideration only relative size of lightness difference against the shared region. Specifically, the probability that the left disk is perceived as being in front is proportional to (|b - q| - |p - q|) / (|b - q| + |p - q|) calculated based on lightness.

How Ghanaian, African-Surinamese and Dutch patients perceive and manage antihypertensive drug treatment: a qualitative study.

PubMed

Beune, Erik J A J; Haafkens, Joke A; Agyemang, Charles; Schuster, John S; Willems, Dick L

2008-04-01

To explore and compare how Ghanaian, African-Surinamese (Surinamese), and White-Dutch patients perceive and manage antihypertensive drug treatment in Amsterdam, the Netherlands. Qualitative study was conducted using detailed interviews with a purposive sample of 46 hypertensive patients without comorbidity who were prescribed antihypertensives. Patients in all the ethnic groups actively decided how to manage their prescribed antihypertensive regimens. In all the groups, confidence in the doctor and beneficial effects of medication were reasons for taking prescribed antihypertensive dosage. Particularly, ethnic-minority patients reported lowering or leaving off the prescribed medication dosage. Explanations for altering prescribed dosage comprised disliking chemical medications, fear of side effects and preference for alternative treatment. Surinamese and Ghanaian men also worried about the negative effects of antihypertensives on their sexual performance. Some Ghanaians mentioned fear of addiction or lack of money as explanations for altering prescribed dosage. Surinamese and Ghanaians often discontinued medication when visiting their homeland. Some respondents from all ethnic groups preferred natural treatments although treatment type varied. Patients' explanations for their decisions regarding the use of antihypertensives are often influenced by sociocultural issues and in ethnic-minority groups also by migration-related issues. Self-alteration of prescribed medication among Surinamese and Ghanaians may contribute to the low blood pressure (BP) control rate and high rate of malignant hypertension reported among these populations in the Netherlands. This study provides new information, which can help clinicians to understand how patients of diverse ethnic populations think about managing antihypertensive drug treatment and to address ethnic disparities in medication adherence and BP control.

Perceived Stress after Acute Myocardial Infarction: A Comparison between Young and Middle-Aged Women versus Men

PubMed Central

Xu, Xiao; Bao, Haikun; Strait, Kelly M.; Edmondson, Donald E.; Davidson, Karina W.; Beltrame, John F.; Bueno, Héctor; Lin, Haiqun; Dreyer, Rachel P.; Brush, John E.; Spertus, John A.; Lichtman, Judith H.; D’Onofrio, Gail; Krumholz, Harlan M.

2017-01-01

Objective To examine how psychological stress changes over time in young and middle-aged patients after experiencing an acute myocardial infarction (AMI) and whether these changes over time differ between men and women. Methods We analyzed data obtained from 2,358 women and 1,151 men aged 18–55 years hospitalized for an AMI. Psychological stress was measured using the 14-item Perceived Stress Scale (PSS-14) at initial hospitalization and at 1 and 12 months after AMI. We used linear mixed effects models to examine changes in PSS-14 scores over time and sex differences in these changes, while adjusting for patient characteristics and accounting for correlation among repeated observations within patients. Results Overall, patients’ perceived stress decreased over time, especially during the first month after AMI. Women had higher levels of perceived stress than men throughout the 12-month period (difference in PSS-14 score = 3.63, 95% confidence interval [CI] = 3.08 to 4.18, p<.001), but they did not differ in how stress changed over time. Adjustment for patient characteristics did not alter the overall pattern of sex difference in changes of perceived stress over time other than attenuating the magnitude of sex difference in PSS-14 score (difference between women and men = 1.74, 95% CI: 1.32 to 2.16, p<.001). The magnitude of sex differences in perceived stress was similar in patients with versus without post-AMI angina, even though patients with angina experienced less improvement in PSS-14 score than those without angina. Conclusions In young and middle-aged patients with AMI, women reported higher levels of perceived stress than men throughout the first 12 months of recovery. However, women and men had a similar pattern in how perceived stress changed over time. PMID:27984507

IS NITROGEN DEPOSITION ALTERING THE NITROGEN STATUS OF NORTHEASTERN FORESTS?

EPA Science Inventory

This paper reviews literature and compiles existing data to address the question "Is N deposition altering the N status in Northeastern forests?" Using correlational techniques and large sample size, three different categories of indicators appear to give different results. The...

Size speed bias or size arrival effect-How judgments of vehicles' approach speed and time to arrival are influenced by the vehicles' size.

PubMed

Petzoldt, Tibor

2016-10-01

Crashes at railway level crossings are a key problem for railway operations. It has been suggested that a potential explanation for such crashes might lie in a so-called size speed bias, which describes the phenomenon that observers underestimate the speed of larger objects, such as aircraft or trains. While there is some evidence that this size speed bias indeed exists, it is somewhat at odds with another well researched phenomenon, the size arrival effect. When asked to judge the time it takes an approaching object to arrive at a predefined position (time to arrival, TTA), observers tend to provide lower estimates for larger objects. In that case, road users' crossing decisions when confronted with larger vehicles should be rather conservative, which has been confirmed in multiple studies on gap acceptance. The aim of the experiment reported in this paper was to clarify the relationship between size speed bias and size arrival effect. Employing a relative judgment task, both speed and TTA estimates were assessed for virtual depictions of a train and a truck, using a car as a reference to compare against. The results confirmed the size speed bias for the speed judgments, with both train and truck being perceived as travelling slower than the car. A comparable bias was also present in the TTA estimates for the truck. In contrast, no size arrival effect could be found for the train or the truck, neither in the speed nor the TTA judgments. This finding is inconsistent with the fact that crossing behaviour when confronted with larger vehicles appears to be consistently more conservative. This discrepancy might be interpreted as an indication that factors other than perceived speed or TTA play an important role for the differences in gap acceptance between different types of vehicles. Copyright © 2016 Elsevier Ltd. All rights reserved.

Identification of Crystalline Minerals in Volcanic Alteration Products and Applications to the Surface of Mars

NASA Technical Reports Server (NTRS)

Bishop, J. L.; Madsen, M. B.; Murad, E.; Wagner, P. A.

2000-01-01

Visible, infrared and Mossbauer spectra have been measured for fine-grained alteration products of volcanic tephra and ash. Comparison of the spectral and chemical properties for different size separates and related samples provides information about the crystalline materials in these samples and how they may have formed. Hydrothermal processes can increase the alteration rates of the primary minerals and glass and provide S, Fe and/or water for formation of sulfates and hydrated minerals. Identification of crystalline alteration minerals on Mars may indicate hydrothermal alteration and sites of interesting geologic processes.

Size of the social network versus quality of social support: which is more protective against PTSD?

PubMed

Platt, Jonathan; Keyes, Katherine M; Koenen, Karestan C

2014-08-01

Supportive social networks are important to the post-traumatic response process. However, the effects of social network structure may be distinct from the perceived function of those networks. The present study examined the relative importance of role diversity and perceived strength of social support in mitigating post-traumatic stress disorder (PTSD). Data were drawn from respondents who report lifetime potentially traumatic events in the National Epidemiologic Survey on Alcohol and Related Conditions (N = 31,650). The Social Network Index (SNI) was used to measure the diversity of social connections. The Interpersonal Support Evaluation List (ISEL-12) was used to measure the perceived availability of social support within the network. Odds of current PTSD were compared among individuals representing four dichotomous types of social support: high diversity/high perceived strength, high diversity/low perceived strength, low diversity/high perceived strength, and low diversity/low perceived strength to examine which type of support is more protective against PTSD. Unadjusted odds of PTSD were 1.59 (95 % CI 1.39-1.82) for those with low versus high perceived support strength, and 1.10 (0.94-1.28) among those with non-diverse versus diverse social networks. Compared to the reference group (high diversity/high perceived strength), the adjusted odds of current PTSD were higher for two groups: low diversity/low perceived strength (OR = 1.62; 1.33-1.99), and low diversity/high perceived strength (OR = 1.57; 1.3-1.91). The high diversity/low perceived strength group had no greater odds of PTSD (OR = 1.02; 0.81-1.28). The diversity of a social network is potentially more protective against PTSD than the perception of strong social support. This suggests that programs, which engage individuals in social groups and activities may effectively attenuate the risk of PTSD. A better understanding of how these networks operate with respect to PTSD prevention and mitigation holds promise for improving psychiatric health.

The influence of vision, touch, and proprioception on body representation of the lower limbs.

PubMed

Stone, Kayla D; Keizer, Anouk; Dijkerman, H Chris

2018-04-01

Numerous studies have shown that the representation of the hand is distorted. When participants are asked to localize unseen points on the hand (e.g. the knuckle), it is perceived to be wider and shorter than its physical dimensions. Similar distortions occur when people are asked to judge the distance between two tactile points on the hand; estimates made in the longitudinal direction are perceived as significantly shorter than those made in the transverse direction. Yet, when asked to visually compare the shape and size of one's own hand to a template hand, individuals are accurate at estimating the size of their own hands. Thus, it seems that body representations are, at least in part, a function of the most prominent underlying sensory modality used to perceive the body part. Yet, it remains unknown if the representations of other body parts are similarly distorted. The lower limbs, for example, are structurally and functionally very different from the hands, yet their representation(s) are seldom studied. What does the body representation for the leg look like? And is leg representation dependent on which sense is probed when making judgments about its shape and size? In the current study, we investigated what the representation of the leg looks like in visually-, tactually-, and proprioceptively-guided tasks. Results revealed that the leg, like the hand, is distorted in a highly systematic manner. Distortions seem to rely, at least partly, on sensory input. This is the first study, to our knowledge, to systematically investigate leg representation in healthy individuals. Copyright © 2018 Elsevier B.V. All rights reserved.

Associations Between Fetal Growth and Self-Perceived Health Throughout Adulthood: A Co-twin Control Study.

PubMed

Mosing, Miriam A; Cnattingius, Sven; Gatz, Margaret; Neiderhiser, Jenae M; Pedersen, Nancy L

2016-05-01

The literature shows evidence for long-lasting effects of low birth weight (LBW) on many health outcomes, but little is known about effects on self-perceived health. Findings are mixed and studies are small, mostly focusing on LBW effects on health outcomes before adulthood. Further, as LBW and most health conditions including self-perceived health are partly heritable, associations between birth weight (BW) and adverse health outcomes may also be due to shared genetic as well as other (pre- and postnatal) unmeasured environmental influences. We explored LBW effects on self-perceived health in early and later adulthood using a very large and genetically informative sample of more than 50,000 Swedish twins. In addition, analyses within twin pairs (the co-twin control design) were used to examine potential associations between BW and the offspring's risk for poor self-perceived health independent of shared environmental or genetic factors, evidence which is critical for the understanding of underlying mechanisms. Results showed that lower BW was significantly associated with poorer self-perceived health during adulthood, although the effect size was small. Co-twin control analyses suggested that this increased risk may be due to shared underlying liability (environmental or genetic) rather than a direct effect of BW, but findings were not conclusive.

Community Cleavages: Gay and Bisexual Men’s Perceptions of Gay and Mainstream Community Acceptance in the Post-AIDS, Post-Rights Era

PubMed Central

Lewis, Nathaniel M.; Bauer, Greta R.; Coleman, Todd A.; Blot, Soraya; Pugh, Daniel; Fraser, Meredith; Powell, Leanne

2015-01-01

Changes in gay and bisexual men’s connectedness to the gay community are related to the declining public visibility of HIV/AIDS and greater acceptance for homosexuality and bisexuality in mainstream society. Little work, however, has focused on perceived acceptance for subgroups within the gay community or broader society. Using interviews (n = 20) and a survey (n = 202) of gay and bisexual men in a mid-sized Canadian city, we find perceived hierarchies of acceptance for the various subgroups as well as an age effect wherein middle-aged men perceive the least acceptance for all groups. These differences are linked with the uneven impact of social, political, and institutional changes relevant to gay and bisexual men in Canada. PMID:26011048

Discrete Element Modeling of Micro-scratch Tests: Investigation of Mechanisms of CO2 Alteration in Reservoir Rocks

NASA Astrophysics Data System (ADS)

Sun, Zhuang; Espinoza, D. Nicolas; Balhoff, Matthew T.; Dewers, Thomas A.

2017-12-01

The injection of CO2 into geological formations leads to geochemical re-equilibrium between the pore fluid and rock minerals. Mineral-brine-CO2 reactions can induce alteration of mechanical properties and affect the structural integrity of the storage formation. The location of alterable mineral phases within the rock skeleton is important to assess the potential effects of mineral dissolution on bulk geomechanical properties. Hence, although often disregarded, the understanding of particle-scale mechanisms responsible for alterations is necessary to predict the extent of geomechanical alteration as a function of dissolved mineral amounts. This study investigates the CO2-related rock chemo-mechanical alteration through numerical modeling and matching of naturally altered rocks probed with micro-scratch tests. We use a model that couples the discrete element method (DEM) and the bonded particle model (BPM) to perform simulations of micro-scratch tests on synthetic rocks that mimic Entrada sandstone. Experimental results serve to calibrate numerical scratch tests with DEM-BPM parameters. Sensitivity analyses indicate that the cement size and bond shear strength are the most sensitive microscopic parameters that govern the CO2-induced alteration in Entrada sandstone. Reductions in cement size lead to decrease in scratch toughness and an increase in ductility in the rock samples. This work demonstrates how small variations of microscopic bond properties in cemented sandstone can lead to significant changes in macroscopic large-strain mechanical properties.

Diversifying the composition and structure of managed late-successional forests with harvest gaps: What is the optimal gap size?

Treesearch

Christel C. Kern; Anthony W. D’Amato; Terry F. Strong

2013-01-01

Managing forests for resilience is crucial in the face of uncertain future environmental conditions. Because harvest gap size alters the species diversity and vertical and horizontal structural heterogeneity, there may be an optimum range of gap sizes for conferring resilience to environmental uncertainty. We examined the impacts of different harvest gap sizes on...

Imaging natural materials with a quasi-microscope. [spectrophotometry of granular materials

NASA Technical Reports Server (NTRS)

Bragg, S.; Arvidson, R.

1977-01-01

A Viking lander camera with auxilliary optics mounted inside the dust post was evaluated to determine its capability for imaging the inorganic properties of granular materials. During mission operations, prepared samples would be delivered to a plate positioned within the camera's field of view and depth of focus. The auxiliary optics would then allow soil samples to be imaged with an 11 pm pixel size in the broad band (high resolution, black and white) mode, and a 33 pm pixel size in the multispectral mode. The equipment will be used to characterize: (1) the size distribution of grains produced by igneous (intrusive and extrusive) processes or by shock metamorphism, (2) the size distribution resulting from crushing, chemical alteration, or by hydraulic or aerodynamic sorting; (3) the shape and degree of grain roundness and surface texture induced by mechanical and chemical alteration; and (4) the mineralogy and chemistry of grains.

Effect of stimuli presentation method on perception of room size using only acoustic cues

NASA Astrophysics Data System (ADS)

Hunt, Jeffrey Barnabas

People listen to music and speech in a large variety of rooms and many room parameters, including the size of the room, can drastically affect how well the speech is understood or the music enjoyed. While multi-modal (typically hearing and sight) tests may be more realistic, in order to isolate what acoustic cues listeners use to determine the size of a room, a listening-only tests is conducted here. Nearly all of the studies to-date on the perception of room volume using acoustic cues have presented the stimuli only over headphones and these studies have reported that, in most cases, the perceived room volume is more highly correlated with the perceived reverberation (reverberance) than with actual room volume. While reverberance may be a salient acoustic cue used for the determination or room size, the actual sound field in a room is not accurately reproduced when presented over headphones and it is thought that some of the complexities of the sound field that relate to perception of geometric volume, specifically directional information of reflections, may be lost. It is possible that the importance of reverberance may be overemphasized when using only headphones to present stimuli so a comparison of room-size perception is proposed where the sound field (from modeled and recorded impulse responses) is presented both over headphones and also over a surround system using higher order ambisonics to more accurately produce directional sound information. Major results are that, in this study, no difference could be seen between the two presentation methods and that reverberation time is highly correlated to room-size perception while real room size is not.

Adolescent screen-viewing behaviour is associated with consumption of sugar-sweetened beverages: the role of habit strength and perceived parental norms.

PubMed

Kremers, Stef P J; van der Horst, Klazine; Brug, Johannes

2007-05-01

The association between adolescent screen-viewing behaviour (i.e., television viewing and computer use) and the consumption of sugar-sweetened beverages was studied in a Dutch sample of adolescents (N=383) using self-administered questionnaires. In particular, the previously understudied role of habit and perceived parental norms in the execution of these behaviours was investigated. Results showed that screen-viewing behaviour was associated with consumption of sugar-sweetened beverages (r=.32). Habit strength of both behaviours correlated with a large effect size (r=.50). The interaction between both behaviours was underlined by the finding that consumption of sugar-sweetened beverages was explained by perceived parental norms regarding screen-viewing behaviour (beta=.12; adjusted for the behaviour and perceived parental norm regarding sugar-sweetened beverage consumption). Consequences of the identified role of habit and parental norms in the interplay between sedentary behaviour and consumption of sugar-sweetened beverages among adolescents are discussed.

A facial attractiveness account of gender asymmetries in interracial marriage.

PubMed

Lewis, Michael B

2012-01-01

In the US and UK, more Black men are married to White women than vice versa and there are more White men married to Asian women than vice versa. Models of interracial marriage, based on the exchange of racial status for other capital, cannot explain these asymmetries. A new explanation is offered based on the relative perceived facial attractiveness of the different race-by-gender groups. This explanation was tested using a survey of perceived facial attractiveness. This found that Black males are perceived as more attractive than White or East Asian males whereas among females, it is the East Asians that are perceived as most attractive on average. Incorporating these attractiveness patterns into the model of marriage decisions produces asymmetries in interracial marriage similar to those in the observed data in terms of direction and relative size. This model does not require differences in status between races nor different strategies based on gender. Predictions are also generated regarding the relative attractiveness of those engaging in interracial marriage.

Effects of lipid emulsion particle size on satiety and energy intake: a randomised cross-over trial.

PubMed

Poppitt, Sally D; Budgett, Stephanie C; MacGibbon, Alastair K; Quek, Siew-Young; Kindleysides, Sophie; Wiessing, Katy R

2018-03-01

Emulsified lipids, with central lipid core surrounded by polar lipid 'protective coat', have been proposed to stimulate the ileal brake, alter appetite, food intake and aid weight control. In addition to lipid composition, emulsion particle size may contribute to efficacy with small droplets providing a larger surface area for gastrointestinal (GI) lipase action and larger droplets prolonging and delaying digestion in the GI tract. Tube feeding studies delivering emulsions directly into the small intestine show clear effects of smaller particle size on appetite and food intake, but evidence from oral feeding studies is sparse. The objective of this study was to determine the effects of lipid emulsion particle size on appetite response and food intake. In a three-arm randomised cross-over, high-phospholipid (PL) dairy lipid emulsions or matched control were consumed at breakfast within a yoghurt smoothie: (i) large-particle size emulsion, LPE (diameter 0.759 µm, 10 g lipid emulsion, 190 g yoghurt), (ii) small-particle size emulsion, SPE (diameter 0.290 µm, 10 g lipid emulsion, 190 g yoghurt), (iii) control non-emulsion, NE (10 g non-emulsion lipid, 190 g yoghurt). Twenty male participants completed the study, where postprandial appetite response was rated using visual analogue scales (VAS) and ad libitum energy intake at a lunch meal measured 3 h later. There was a trend for LPE to suppress hunger (P = 0.08) and enhance fullness (P = 0.24) relative to both SPE and NE but not statistically significant, and no significant effect of either emulsion on food intake at the lunch meal (P > 0.05). Altering particle size of a high-PL emulsion did not enhance satiety or alter eating behaviour in a group of lean men.

Ablation and Chemical Alteration of Cosmic Dust Particles during Entry into the Earth’s Atmosphere

NASA Astrophysics Data System (ADS)

Rudraswami, N. G.; Shyam Prasad, M.; Dey, S.; Plane, J. M. C.; Feng, W.; Carrillo-Sánchez, J. D.; Fernandes, D.

2016-12-01

Most dust-sized cosmic particles undergo ablation and chemical alteration during atmospheric entry, which alters their original properties. A comprehensive understanding of this process is essential in order to decipher their pre-entry characteristics. The purpose of the study is to illustrate the process of vaporization of different elements for various entry parameters. The numerical results for particles of various sizes and various zenith angles are treated in order to understand the changes in chemical composition that the particles undergo as they enter the atmosphere. Particles with large sizes (> few hundred μm) and high entry velocities (>16 km s‑1) experience less time at peak temperatures compared to those that have lower velocities. Model calculations suggest that particles can survive with an entry velocity of 11 km s‑1 and zenith angles (ZA) of 30°–90°, which accounts for ∼66% of the region where particles retain their identities. Our results suggest that the changes in chemical composition of MgO, SiO2, and FeO are not significant for an entry velocity of 11 km s‑1 and sizes <300 μm, but the changes in these compositions become significant beyond this size, where FeO is lost to a major extent. However, at 16 km s‑1 the changes in MgO, SiO2, and FeO are very intense, which is also reflected in Mg/Si, Fe/Si, Ca/Si, and Al/Si ratios, even for particles with a size of 100 μm. Beyond 400 μm particle sizes at 16 km s‑1, most of the major elements are vaporized, leaving the refractory elements, Al and Ca, suspended in the troposphere.

Altering Pace Control and Pace Regulation: Attentional Focus Effects during Running.

PubMed

Brick, Noel E; Campbell, Mark J; Metcalfe, Richard S; Mair, Jacqueline L; Macintyre, Tadhg E

2016-05-01

To date, there are no published studies directly comparing self-controlled (SC) and externally controlled (EC) pace endurance tasks. However, previous research suggests pace control may impact on cognitive strategy use and effort perceptions. The primary aim of this study was to investigate the effects of manipulating perception of pace control on attentional focus, physiological, and psychological outcomes during running. The secondary aim was to determine the reproducibility of self-paced running performance when regulated by effort perceptions. Twenty experienced endurance runners completed four 3-km time trials on a treadmill. Subjects completed two SC pace trials, one perceived exertion clamped (PE) trial, and one EC pace time trial. PE and EC were completed in a counterbalanced order. Pacing strategy for EC and perceived exertion instructions for PE replicated the subjects' fastest SC time trial. Subjects reported a greater focus on cognitive strategies such as relaxing and optimizing running action during EC than during SC. The mean HR was 2% lower during EC than that during SC despite an identical pacing strategy. Perceived exertion did not differ between the three conditions. However, increased internal sensory monitoring coincided with elevated effort perceptions in some subjects during EC and a 10% slower completion time for PE (13.0 ± 1.6 min) than that for SC (11.8 ± 1.2 min). Altering pace control and pace regulation impacted on attentional focus. External control over pacing may facilitate performance, particularly when runners engage attentional strategies conducive to improved running efficiency. However, regulating pace based on effort perceptions alone may result in excessive monitoring of bodily sensations and a slower running speed. Accordingly, attentional focus interventions may prove beneficial for some athletes to adopt task-appropriate attentional strategies to optimize performance.

The Effect of Traditional Singing Warm-Up Versus Semioccluded Vocal Tract Exercises on the Acoustic Parameters of Singing Voice.

PubMed

Duke, Emily; Plexico, Laura W; Sandage, Mary J; Hoch, Matthew

2015-11-01

This study investigated the effect of traditional vocal warm-up versus semioccluded vocal tract exercises on the acoustic parameters of voice through three questions: does vocal warm-up condition significantly alter the singing power ratio of the singing voice? Is singing power ratio dependent upon vowel? Is perceived phonatory effort affected by warm-up condition? Hypotheses were that vocal warm-up would alter the singing power ratio, and that semioccluded vocal tract warm-up would affect the singing power ratio more than no warm-up or traditional warm-up, that singing power ratio would vary across vowel, and that perceived phonatory effort would vary with warm-up condition. This study was a within-participant repeated measures design with counterbalanced conditions. Thirteen male singers were recorded under three different conditions: no warm-up, traditional warm-up, and semioccluded vocal tract exercise warm-up. Recordings were made of these singers performing the Star Spangled Banner, and singing power ratio (SPR) was calculated from four vowels. Singers rated their perceived phonatory effort (PPE) singing the Star Spangled Banner after each warm-up condition. Warm-up condition did not significantly affect SPR. SPR was significantly different for /i/ and /e/. PPE was not significantly different between warm-up conditions. The present study did not find significant differences in SPR between warm-up conditions. SPR differences for /i/, support previous findings. PPE did not differ significantly across warm-up condition despite the expectation that traditional or semioccluded warm-up would cause a decrease. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Ghrelin increases the motivation to eat, but does not alter food palatability

PubMed Central

Overduin, Joost; Figlewicz, Dianne P.; Bennett-Jay, Jennifer; Kittleson, Sepideh

2012-01-01

Homeostatic eating cannot explain overconsumption of food and pathological weight gain. A more likely factor promoting excessive eating is food reward and its representation in the central nervous system (CNS). The anorectic hormones leptin and insulin reduce food reward and inhibit related CNS reward pathways. Conversely, the orexigenic gastrointestinal hormone ghrelin activates both homeostatic and reward-related neurocircuits. The current studies were conducted to identify in rats the effects of intracerebroventricular ghrelin infusions on two distinct aspects of food reward: hedonic valuation (i.e., “liking”) and the motivation to self-administer (i.e., “wanting”) food. To assess hedonic valuation of liquid food, lick motor patterns were recorded using lickometry. Although ghrelin administration increased energy intake, it did not alter the avidity of licking (initial lick rates or lick-cluster size). Several positive-control conditions ruled out lick-rate ceiling effects. Similarly, when the liquid diet was hedonically devalued with quinine supplementation, ghrelin failed to reverse the quinine-associated reduction of energy intake and avidity of licking. The effects of ghrelin on rats' motivation to eat were assessed using lever pressing to self-administer food in a progressive-ratio paradigm. Ghrelin markedly increased motivation to eat, to levels comparable to or greater than those seen following 24 h of food deprivation. Pretreatment with the dopamine D1 receptor antagonist SCH-23390 eliminated ghrelin-induced increases in lever pressing, without compromising generalized licking motor control, indicating a role for D1 signaling in ghrelin's motivational feeding effects. These results indicate that ghrelin increases the motivation to eat via D1 receptor-dependent mechanisms, without affecting perceived food palatability. PMID:22673784

Evidence-based tailoring of behavior-change campaigns: increasing fluoride-free water consumption in rural Ethiopia with persuasion.

PubMed

Huber, Alexandra C; Tobias, Robert; Mosler, Hans-Joachim

2014-03-01

Two hundred million people worldwide are at risk of developing dental and skeletal fluorosis due to excessive fluoride uptake from their water. Since medical treatment of the disease is difficult and mostly ineffective, preventing fluoride uptake is crucial. In the Ethiopian Rift Valley, a fluoride-removal community filter was installed. Despite having access to a fluoride filter, the community used the filter sparingly. During a baseline assessment, 173 face-to-face interviews were conducted to identify psychological factors that influence fluoride-free water consumption. Based on the results, two behavior-change campaigns were implemented: a traditional information intervention targeting perceived vulnerability, and an evidence-based persuasion intervention regarding perceived costs. The interventions were tailored to household characteristics. The campaigns were evaluated with a survey and analyzed in terms of their effectiveness in changing behavior and targeted psychological factors. While the intervention targeting perceived vulnerability showed no desirable effects, cost persuasion decreased the perceived costs and increased the consumption of fluoride-free water. This showed that altering subjective perceptions can change behavior even without changing objective circumstances. Moreover, interventions are more effective if they are based on evidence and tailored to specific households. © 2013 The International Association of Applied Psychology.

Execution of saccadic eye movements affects speed perception

PubMed Central

Goettker, Alexander; Braun, Doris I.; Schütz, Alexander C.; Gegenfurtner, Karl R.

2018-01-01

Due to the foveal organization of our visual system we have to constantly move our eyes to gain precise information about our environment. Doing so massively alters the retinal input. This is problematic for the perception of moving objects, because physical motion and retinal motion become decoupled and the brain has to discount the eye movements to recover the speed of moving objects. Two different types of eye movements, pursuit and saccades, are combined for tracking. We investigated how the way we track moving targets can affect the perceived target speed. We found that the execution of corrective saccades during pursuit initiation modifies how fast the target is perceived compared with pure pursuit. When participants executed a forward (catch-up) saccade they perceived the target to be moving faster. When they executed a backward saccade they perceived the target to be moving more slowly. Variations in pursuit velocity without corrective saccades did not affect perceptual judgments. We present a model for these effects, assuming that the eye velocity signal for small corrective saccades gets integrated with the retinal velocity signal during pursuit. In our model, the execution of corrective saccades modulates the integration of these two signals by giving less weight to the retinal information around the time of corrective saccades. PMID:29440494

Influence of foot orthosis customisation on perceived comfort during running.

PubMed

Lucas-Cuevas, A G; Pérez-Soriano, P; Priego-Quesada, J I; Llana-Belloch, S

2014-01-01

Although running is associated with many health benefits, it also exposes the body to greater risk of injury. Foot orthoses are an effective strategy to prevent such injuries. Comfort is an essential element in orthosis design since any discomfort alters the runner's biomechanics, compromising performance and increasing the risk of injury. The present study analyses the perceived comfort of three types of orthoses: custom-made, prefabricated and original running shoe insoles. Nine comfort variables for each insole were assessed in a sample of 40 runners. Custom-made and prefabricated insoles were both perceived as significantly more comfortable than the original insoles. The differences were clinically relevant and were potentially causes of modifications in running gait. Although the prefabricated insoles were rated slightly higher than the custom-made insoles, the differences were not statistically significant. This study shows that prefabricated insoles constitute a reasonable alternative to custom-made insoles in terms of comfort. The perceived level of comfort of footwear is considered to be a protective measure of the potential risk of running injuries. We here compared runners' perception of comfort of custom-made and prefabricated orthoses while running. We found that even though custom-made orthoses are closely matched to each individual's foot, such customisation does not necessarily imply greater comfort.

A link between individual differences in multisensory speech perception and eye movements

PubMed Central

Gurler, Demet; Doyle, Nathan; Walker, Edgar; Magnotti, John; Beauchamp, Michael

2015-01-01

The McGurk effect is an illusion in which visual speech information dramatically alters the perception of auditory speech. However, there is a high degree of individual variability in how frequently the illusion is perceived: some individuals almost always perceive the McGurk effect, while others rarely do. Another axis of individual variability is the pattern of eye movements make while viewing a talking face: some individuals often fixate the mouth of the talker, while others rarely do. Since the talker's mouth carries the visual speech necessary information to induce the McGurk effect, we hypothesized that individuals who frequently perceive the McGurk effect should spend more time fixating the talker's mouth. We used infrared eye tracking to study eye movements as 40 participants viewed audiovisual speech. Frequent perceivers of the McGurk effect were more likely to fixate the mouth of the talker, and there was a significant correlation between McGurk frequency and mouth looking time. The noisy encoding of disparity model of McGurk perception showed that individuals who frequently fixated the mouth had lower sensory noise and higher disparity thresholds than those who rarely fixated the mouth. Differences in eye movements when viewing the talker's face may be an important contributor to interindividual differences in multisensory speech perception. PMID:25810157

Egocentric networks of Chinese men who have sex with men: network components, condom use norms, and safer sex.

PubMed

Liu, Hongjie; Feng, Tiejian; Liu, Hui; Feng, Hucang; Cai, Yumao; Rhodes, Anne G; Grusky, Oscar

2009-10-01

Research on risk behaviors among men who have sex with men (MSM) is often based on individualistic models of health behavior, but sexual behavior is inherently social in nature and often determined by constituents of social networks. The objective of this study was to examine relationships among social networks, network norms of condom use, and safer sex. A respondent-driven sampling study recruited 350 MSM in the Shenzhen region of China between November and December 2007 and collected information on network components (relations, structures, and functions) and HIV risk behavior among egos (those interviewed) and their network alters. A total of 2385 alters were nominated by the 350 egos. Egos reported an average of 4 nonsexual relation alters and 2 sexual-partner alters. Egos perceived receiving more tangible and emotional support from nonsexual relation alters than from sexual-partner alters. Two thirds (69%) of egos consistently used condoms. Sixty-seven percent of egos reported having 1 or more alters who always encouraged egos to use condoms, 84% had 1 or more alters who consistently used condoms, and 55% had 1 or more alters who insisted on condom use. Both subjective and descriptive norms were positively associated with consistent condom use. Network components were associated with the levels of the two norms. These findings suggest that social network components may activate or strengthen condom use norms within networks, which, in turn, determine consistent condom use among MSM. HIV behavioral interventions need to target the promotion of safer sex practices through enhancing peer norms of condom use within networks.

Centrifuges in gravitational physiology research

NASA Technical Reports Server (NTRS)

Ballard, Rodney W.; Davies, Phil; Fuller, Charles A.

1993-01-01

Data from space flight and ground based experiments have clearly demonstrated the importance of Earth gravity for normal physiological function in man and animals. Gravitational Physiology is concerned with the role and influence of gravity on physiological systems. Research in this field examines how we perceive and respond to gravity and the mechanisms underlying these responses. Inherent in our search for answers to these questions is the ability to alter gravity, which is not physically possible without leaving Earth. However, useful experimental paradigms have been to modify the perceived force of gravity by changing either the orientation of subjects to the gravity vector (i.e., postural changes) or by applying inertial forces to augment the magnitude of the gravity vector. The later technique has commonly been used by applying centripetal force via centrifugation.

The moon illusion and size-distance scaling--evidence for shared neural patterns.

PubMed

Weidner, Ralph; Plewan, Thorsten; Chen, Qi; Buchner, Axel; Weiss, Peter H; Fink, Gereon R

2014-08-01

A moon near to the horizon is perceived larger than a moon at the zenith, although--obviously--the moon does not change its size. In this study, the neural mechanisms underlying the "moon illusion" were investigated using a virtual 3-D environment and fMRI. Illusory perception of an increased moon size was associated with increased neural activity in ventral visual pathway areas including the lingual and fusiform gyri. The functional role of these areas was further explored in a second experiment. Left V3v was found to be involved in integrating retinal size and distance information, thus indicating that the brain regions that dynamically integrate retinal size and distance play a key role in generating the moon illusion.

Perceptions as the crucial link? The mediating role of neighborhood perceptions in the relationship between the neighborhood context and neighborhood cohesion.

PubMed

Laméris, Joran; Hipp, John R; Tolsma, Jochem

2018-05-01

This study examines the effects of neighborhood racial in-group size, economic deprivation and the prevalence of crime on neighborhood cohesion among U.S. whites. We explore to what extent residents' perceptions of their neighborhood mediate these macro-micro relationships. We use a recent individual-level data set, the American Social Fabric Study (2012/2013), enriched with contextual-level data from the U.S. Census Bureau (2010) and employ multi-level structural equation models. We show that the racial in-group size is positively related to neighborhood cohesion and that neighborhood cohesion is lower in communities with a high crime rate. Individuals' perceptions of the racial in-group size partly mediate the relationship between the objective racial in-group size and neighborhood cohesion. Residents' perceptions of unsafety from crime also appear to be a mediating factor, not only for the objective crime rate but also for the objective racial in-group size. This is in line with our idea that racial stereotypes link racial minorities to crime whereby neighborhoods with a large non-white population are perceived to be more unsafe. Residents of the same neighborhood differ in how they perceive the degree of economic decay of the neighborhood and this causes them to evaluate neighborhood cohesion differently, however perceptions of neighborhood economic decay do not explain the link between the objective neighborhood context and neighborhood cohesion. Copyright © 2018. Published by Elsevier Inc.

The thrombospondin-1 N700S polymorphism is associated with early myocardial infarction without altering von Willebrand factor multimer size.

PubMed

Zwicker, Jeffrey I; Peyvandi, Flora; Palla, Roberta; Lombardi, Rossana; Canciani, Maria Teresa; Cairo, Andrea; Ardissino, Diego; Bernardinelli, Luisa; Bauer, Kenneth A; Lawler, Jack; Mannucci, Pier

2006-08-15

The N700S polymorphism of thrombospondin-1 (TSP-1) has been identified as a potential genetic risk factor for myocardial infarction (MI). In a large case-control study of 1425 individuals who survived a myocardial infarction prior to age 45, the N700S polymorphism was a significant risk factor for myocardial infarction in both homozygous (odds ratio [OR] 1.9, 95% confidence interval [CI] 1.1-3.3, P = .01) and heterozygous carriers of the S700 allele (OR 1.4, 95% CI 1.1-3.3, P = .01). TSP-1 has been shown to reduce von Willebrand factor (VWF) multimer size, and the domain responsible for VWF-reducing activity has been localized to the calcium-binding C-terminal sequence. As the N700S polymorphism was previously shown to alter the function of this domain, we investigated whether the altered VWF-reducing activity of TSP-1 underlies the observed prothrombotic phenotype. The TSP1 N700S polymorphism did not influence VWF multimer size in patients homozygous for either allele nor was there a significant reduction of VWF multimer size following incubation with recombinant N700S fragments or platelet-derived TSP-1.

The thrombospondin-1 N700S polymorphism is associated with early myocardial infarction without altering von Willebrand factor multimer size

PubMed Central

Zwicker, Jeffrey I.; Peyvandi, Flora; Palla, Roberta; Lombardi, Rossana; Canciani, Maria Teresa; Cairo, Andrea; Ardissino, Diego; Bernardinelli, Luisa; Bauer, Kenneth A.; Lawler, Jack; Mannucci, Pier

2006-01-01

The N700S polymorphism of thrombospondin-1 (TSP-1) has been identified as a potential genetic risk factor for myocardial infarction (MI). In a large case-control study of 1425 individuals who survived a myocardial infarction prior to age 45, the N700S polymorphism was a significant risk factor for myocardial infarction in both homozygous (odds ratio [OR] 1.9, 95% confidence interval [CI] 1.1-3.3, P = .01) and heterozygous carriers of the S700 allele (OR 1.4, 95% CI 1.1-3.3, P = .01). TSP-1 has been shown to reduce von Willebrand factor (VWF) multimer size, and the domain responsible for VWF-reducing activity has been localized to the calcium-binding C-terminal sequence. As the N700S polymorphism was previously shown to alter the function of this domain, we investigated whether the altered VWF-reducing activity of TSP-1 underlies the observed prothrombotic phenotype. The TSP1 N700S polymorphism did not influence VWF multimer size in patients homozygous for either allele nor was there a significant reduction of VWF multimer size following incubation with recombinant N700S fragments or platelet-derived TSP-1. PMID:16684956

Implementing Cardiopulmonary Resuscitation Training Programs in High Schools: Iowa's Experience.

PubMed

Hoyme, Derek B; Atkins, Dianne L

2017-02-01

To understand perceived barriers to providing cardiopulmonary resuscitation (CPR) education, implementation processes, and practices in high schools. Iowa has required CPR as a graduation requirement since 2011 as an unfunded mandate. A cross-sectional study was performed through multiple choice surveys sent to Iowa high schools to collect data about school demographics, details of CPR programs, cost, logistics, and barriers to implementation, as well as automated external defibrillator training and availability. Eighty-four schools responded (26%), with the most frequently reported school size of 100-500 students and faculty size of 25-50. When the law took effect, 51% of schools had training programs already in place; at the time of the study, 96% had successfully implemented CPR training. Perceived barriers to implementation were staffing, time commitment, equipment availability, and cost. The average estimated startup cost was <$1000 US, and the yearly maintenance cost was <$500 with funds typically allocated from existing school resources. The facilitator was a school official or volunteer for 81% of schools. Average estimated training time commitment per student was <2 hours. Automated external defibrillators are available in 98% of schools, and 61% include automated external defibrillator training in their curriculum. Despite perceived barriers, school CPR training programs can be implemented with reasonable resource and time allocations. Copyright © 2016 Elsevier Inc. All rights reserved.

Implementing Cardiopulmonary Resuscitation Training Programs in High Schools: Iowa's Experience

PubMed Central

Hoyme, Derek B.; Atkins, Dianne L.

2017-01-01

Objective To understand perceived barriers to providing cardiopulmonary resuscitation (CPR) education, implementation processes, and practices in high schools. Study design Iowa has required CPR as a graduation requirement since 2011 as an unfunded mandate. A cross-sectional study was performed through multiple choice surveys sent to Iowa high schools to collect data about school demographics, details of CPR programs, cost, logistics, and barriers to implementation, as well as automated external defibrillator training and availability. Results Eighty-four schools responded (26%), with the most frequently reported school size of 100-500 students and faculty size of 25-50. When the law took effect, 51% of schools had training programs already in place; at the time of the study, 96% had successfully implemented CPR training. Perceived barriers to implementation were staffing, time commitment, equipment availability, and cost. The average estimated startup cost was <$1000 US, and the yearly maintenance cost was <$500 with funds typically allocated from existing school resources. The facilitator was a school official or volunteer for 81% of schools. Average estimated training time commitment per student was <2 hours. Automated external defibrillators are available in 98% of schools, and 61% include automated external defibrillator training in their curriculum. Conclusions Despite perceived barriers, school CPR training programs can be implemented with reasonable resource and time allocations. PMID:27852456

Neuroticism as distancing: perceptual sources of evidence.

PubMed

Liu, Tianwei; Ode, Scott; Moeller, Sara K; Robinson, Michael D

2013-05-01

Several theories and self-reported sources of data link individual differences in negative affectivity to avoidance motivation. Chronic avoidance motivation, through repeated practice, may result in a relatively cognitive distance-enhancing dynamic whereby events and stimuli are perceived as further away from the self, even when they are not threatening. Such predictions are novel but follow from cybernetic theories of self-regulation. In 5 studies (total N = 463), relations of this type were investigated. Study 1 presented participants with phrases that were ambiguous and found that trait negative affect predicted phrase interpretation in a distance-enhancing temporal direction. Study 2 replicated this effect across a systematic manipulation of event valence. Study 3 asked individuals to estimate the size of words and found that individuals higher in neuroticism generally perceived words to be smaller than did individuals lower in neuroticism. In Study 4, people high (but not low) in neuroticism perceived words to be shrinking faster than they were growing. In Study 5, greater perceptual distancing, in a font size estimation task, predicted more adverse reactions to negative events in daily life. Although normative effects varied across studies, consistent support for a chronic distancing perspective of individual differences in negative affectivity was found. PsycINFO Database Record (c) 2013 APA, all rights reserved

Pilot Study of Parent Psychophysiologic Outcomes in Pediatric Hematopoietic Stem Cell Transplantation

PubMed Central

Ward, Jessica; Swanson, Barbara; Fogg, Louis; Rodgers, Cheryl

2016-01-01

Background Parents of children undergoing hematopoietic stem cell transplantation (HSCT) are at risk for psychological distress. This distress may result in aberrant immune, inflammatory or endocrine effects. These physiologic outcomes have not been reported previously. Main Objective To examine the feasibility of longitudinal testing of psychophysiological parameters of stress in parents of children undergoing HSCT. Methods This pilot study was conducted at a large children's hospital in the Midwest, and included parents of children who received autologous or allogeneic HSCT. Time points included: prior to start of HSCT conditioning, day +30, +60, and +100. Outcome variables included parent perceived stress, lymphocyte subsets, c-reactive protein (CRP), pro-inflammatory cytokines, salivary cortisol, and salivary amylase. Effect sizes were calculated for each outcome. Results Twelve parent-child dyads were enrolled (10 mothers, 2 fathers). Missing data was minimal. Parent perceived stress significantly increased from pre-HSCT through day +100, and parent CD3+ T lymphocyte counts decreased from pre-HSCT through day +100. No significant effects were observed for salivary studies, CRP, or pro-inflammatory cytokines. Effect sizes ranged from 1.23 (perceived stress) to 0.07 (CRP). Conclusion Results of this study suggest that it is feasible longitudinally measure parent psychophysiologic outcomes in the pediatric HSCT setting. Additionally, parent perceived stress increased linearly from start of conditioning through day +100, while parent T lymphocytes decreased concurrently. Implications for practice Routine psychological and physical health screening of parents of children undergoing HSCT are needed. Multidisciplinary psychosocial support services should be offered to parents at regular intervals during their child's HSCT. PMID:27257801

Manifest Meanings: The Selling (Not Telling) of American Indian History and the Case of "The Black Horse Ledger"

ERIC Educational Resources Information Center

Gercken, Becca

2010-01-01

What is the value or perceived necessity--for an Indian or for a white man--of changing Northern Cheyenne history? How are a reader's conclusions affected by her perception of the race of the person altering that history? Why is it acceptable to sell but not tell American Indian history? An examination of the visual and discursive rhetoric of "The…

Quality of Life in Parents of Young Adults with ASD: EpiTED Cohort

ERIC Educational Resources Information Center

Rattaz, Cécile; Michelon, Cécile; Roeyers, Herbert; Baghdadli, Amaria

2017-01-01

The impact of ASD on parental QOL was evaluated in the EpiTED cohort study at early adulthood. Two-third of parents of young adults with ASD (66.7%) reported that their QoL was at least moderately altered. The perceived impact of ASD on parental QoL was related to the young adults' level of adaptive skills, as well as to symptom severity and the…

48 CFR 2.101 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... research, planning, development, design, construction, alteration, or repair of real property; and (3..., evaluations, consultations, comprehensive planning, program management, conceptual designs, plans and... include the value and size of the modification and the comparative value and size of the final product...

48 CFR 2.101 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... research, planning, development, design, construction, alteration, or repair of real property; and (3..., evaluations, consultations, comprehensive planning, program management, conceptual designs, plans and... minor include the value and size of the modification and the comparative value and size of the final...

Delusional mood and delusional perception -- a phenomenological analysis.

PubMed

Fuchs, Thomas

2005-01-01

In the initial stages of schizophrenia, the environment as perceived by the patient changes into a puzzling, mysterious and stage-like scenery. At the same time, objects or persons may gain an overwhelming physiognomic expression and may even fuse with the patient's body. The paper explains these different alterations using Husserl's concept of intentional perception on the one hand, and Merleau-Ponty's concept of embodied perception on the other hand. The first may also be understood as describing the intersubjective constitution of reality through common concepts which structure intentional perception. The latter points to the embodiment of the perceiving subject and uncovers our intimate connection with the world mediated by the lived body. Thus, in each perception, an active, intentional or 'gnostic' component and a bodily, 'pathic' component work together. On this basis, the alteration of schizophrenic perception in delusional mood may be described as a paralysis of intentionality, or of the 'gnostic' component of perception. The synthetic and sense-bestowing processes effective in perception are seriously disturbed. On the other hand, as a result of the disturbance of intentional perception, physiognomic and expressive properties are set free within the perceptual field. The 'pathic' component of perception becomes independent. Thus, the intersubjective constitution of reality is replaced by idiosyncratic meanings and qualities of perception, leading finally into delusional perception.

Amelioration of cognitive, motor and endogenous defense functions with silymarin, piracetam and protocatechuic acid in the cerebral global ischemic rat model.

PubMed

Muley, Milind M; Thakare, Vishnu N; Patil, Rajesh R; Bafna, Pallavi A; Naik, Suresh R

2013-07-19

The neuroprotective activities of silymarin, piracetam and protocatechuic acid ethyl ester (PCA) on cerebral global ischemic/reperfusion were evaluated in a rat model. A midline ventral incision was made in the throat region. The right and left common carotid arteries were located and a bilateral common carotid artery occlusion (BCCAO) was performed for 30min using atraumatic clamps followed by a 24h period of reperfusion. Neurological/behavioral functions (cognitive and motor), endogenous defense systems (lipid peroxidation, glutathione, catalase, and superoxide dismutase), reduced water content and infarct size and histopathological alterations were then studied. Silymarin and PCA treatments significantly improved cognitive, motor and endogenous defense functions, histopathological alterations, and, reduced both water content and infarct size compared to the vehicle-treated ischemic control group. Piracetam treatment improved neurological and histopathological alterations, reduced water content and infarct size, but failed to restore/prevent the impaired endogenous defense functions significantly. Silymarin showed better neuroprotection than piracetam and PCA in experimentally induced global ischemic/reperfusion and was able to facilitate mnemonic performance. Copyright © 2013 Elsevier Inc. All rights reserved.

Physical characterization and in vitro biological impact of highly aggregated antibodies separated into size-enriched populations by fluorescence-activated cell sorting

PubMed Central

Telikepalli, Srivalli; Shinogle, Heather E.; Thapa, Prem S.; Kim, Jae Hyun; Deshpande, Meghana; Jawa, Vibha; Middaugh, C. Russell; Narhi, Linda O.; Joubert, Marisa K.; Volkin, David B.

2015-01-01

An IgG2 monoclonal antibody (mAb) solution was subjected to stirring, generating high concentrations of nanometer and subvisible particles, which were then successfully size enriched into different size bins by low speed centrifugation or a combination of gravitational sedimentation and Fluorescence-Activated Cell Sorting (FACS). The size-fractionated mAb particles were assessed for their ability to elicit the release of cytokines from a population of donor-derived human peripheral blood mononuclear cells (PBMC) at two phases of the immune response. Fractions enriched in nanometer-sized particles showed a lower response than those enriched in micron-sized particles in this assay. Particles of 5–10 μm in size displayed elevated cytokine release profiles compared to other size ranges. Stir-stressed mAb particles had amorphous morphology, contained protein with partially altered secondary structure, elevated surface hydrophobicity (compared to controls), and trace levels of elemental fluorine. FACS size-enriched the mAb particle samples, yet did not notably alter the overall morphology or composition of particles as measured by Microflow imaging, Transmission Electron Microscopy, and Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy. The utility and limitations of FACS for size separation of mAb particles and potential of in-vitro PBMC studies to rank order the immunogenic potential of various types of mAb particles is discussed. PMID:25753756

Poverty and perceived stress: Evidence from two unconditional cash transfer programs in Zambia.

PubMed

Hjelm, Lisa; Handa, Sudhanshu; de Hoop, Jacobus; Palermo, Tia

2017-03-01

Poverty is a chronic stressor that can lead to poor physical and mental health. This study examines whether two similar government poverty alleviation programs reduced the levels of perceived stress and poverty among poor households in Zambia. Secondary data from two cluster randomized controlled trials were used to evaluate the impacts of two unconditional cash transfer programs in Zambia. Participants were interviewed at baseline and followed over 36 months. Perceived stress among female caregivers was assessed using the Cohen Perceived Stress Scale (PSS). Poverty indicators assessed included per capita expenditure, household food security, and (nonproductive) asset ownership. Fixed effects and ordinary least squares regressions were run, controlling for age, education, marital status, household demographics, location, and poverty status at baseline. Cash transfers did not reduce perceived stress but improved economic security (per capita consumption expenditure, food insecurity, and asset ownership). Among these poverty indicators, only food insecurity was associated with perceived stress. Age and education showed no consistent association with stress, whereas death of a household member was associated with higher stress levels. In this setting, perceived stress was not reduced by a positive income shock but was correlated with food insecurity and household deaths, suggesting that food security is an important stressor in this context. Although the program did reduce food insecurity, the size of the reduction was not enough to generate a statistically significant change in stress levels. The measure used in this study appears not to be correlated with characteristics to which it has been linked in other settings, and thus, further research is needed to examine whether this widely used perceived stress measure appropriately captures the concept of perceived stress in this population. Copyright © 2017 UNICEF. Published by Elsevier Ltd.. All rights reserved.

A simulation analysis to characterize the dynamics of vaccinating behaviour on contact networks.

PubMed

Perisic, Ana; Bauch, Chris T

2009-05-28

Human behavior influences infectious disease transmission, and numerous "prevalence-behavior" models have analyzed this interplay. These previous analyses assumed homogeneously mixing populations without spatial or social structure. However, spatial and social heterogeneity are known to significantly impact transmission dynamics and are particularly relevant for certain diseases. Previous work has demonstrated that social contact structure can change the individual incentive to vaccinate, thus enabling eradication of a disease under a voluntary vaccination policy when the corresponding homogeneous mixing model predicts that eradication is impossible due to free rider effects. Here, we extend this work and characterize the range of possible behavior-prevalence dynamics on a network. We simulate transmission of a vaccine-preventable infection through a random, static contact network. Individuals choose whether or not to vaccinate on any given day according to perceived risks of vaccination and infection. We find three possible outcomes for behavior-prevalence dynamics on this type of network: small final number vaccinated and final epidemic size (due to rapid control through voluntary ring vaccination); large final number vaccinated and significant final epidemic size (due to imperfect voluntary ring vaccination), and little or no vaccination and large final epidemic size (corresponding to little or no voluntary ring vaccination). We also show that the social contact structure enables eradication under a broad range of assumptions, except when vaccine risk is sufficiently high, the disease risk is sufficiently low, or individuals vaccinate too late for the vaccine to be effective. For populations where infection can spread only through social contact network, relatively small differences in parameter values relating to perceived risk or vaccination behavior at the individual level can translate into large differences in population-level outcomes such as final size and final number vaccinated. The qualitative outcome of rational, self interested behaviour under a voluntary vaccination policy can vary substantially depending on interactions between social contact structure, perceived vaccine and disease risks, and the way that individual vaccination decision-making is modelled.

Perceived impact of smaller compared with larger-sized bottles of sugar-sweetened beverages on consumption: A qualitative analysis.

PubMed

Mantzari, Eleni; Hollands, Gareth J; Pechey, Rachel; Jebb, Susan; Marteau, Theresa M

2018-01-01

Sugar-sweetened beverage (SSB) consumption increases obesity risk and is linked to adverse health consequences. Large packages increase food consumption, but most evidence comes from studies comparing larger with standard packages, resulting in uncertainty regarding the impact of smaller packages. There is also little research on beverages. This qualitative study explores the experiences of consuming cola from smaller compared with larger bottles, to inform intervention strategies. Sixteen households in Cambridge, England, participating in a feasibility study assessing the impact of bottle size on in-home SSB consumption, received a set amount of cola each week for four weeks in one of four bottle sizes: 1500 ml, 1000 ml, 500 ml, or 250 ml, in random order. At the study end, household representatives were interviewed about their experiences of using each bottle, including perceptions of i) consumption level; ii) consumption-related behaviours; and iii) factors affecting consumption. Interviews were semi-structured and data analysed using the Framework approach. The present analysis focuses specifically on experiences relating to use of the smaller bottles. The smallest bottles were described as increasing drinking occasion frequency and encouraging consumption of numerous bottles in succession. Factors described as facilitating their consumption were: i) convenience and portability; ii) greater numbers of bottles available, which hindered consumption monitoring and control; iii) perceived insufficient quantity per bottle; and iv) positive attitudes. In a minority of cases the smallest bottles were perceived to have reduced consumption, but this was related to practical issues with the bottles that resulted in dislike. The perception of greater consumption and qualitative reports of drinking habits associated with the smallest bottles raise the possibility that the 'portion size effect' has a lower threshold, beyond which smaller portions and packages may increase consumption. This reinforces the need for empirical evidence to assess the in-home impact of smaller bottles on SSB consumption. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Population-Specific Use of the Same Tool-Assisted Alarm Call between Two Wild Orangutan Populations (Pongopygmaeus wurmbii) Indicates Functional Arbitrariness

PubMed Central

Lameira, Adriano R.; Hardus, Madeleine E.; Nouwen, Kim J. J. M.; Topelberg, Eva; Delgado, Roberto A.; Spruijt, Berry M.; Sterck, Elisabeth H. M.; Knott, Cheryl D.; Wich, Serge A.

2013-01-01

Arbitrariness is an elementary feature of human language, yet seldom an object of comparative inquiry. While arbitrary signals for the same function are relatively frequent between animal populations across taxa, the same signal with arbitrary functions is rare and it remains unknown whether, in parallel with human speech, it may involve call production in animals. To investigate this question, we examined a particular orangutan alarm call – the kiss-squeak – and two variants – hand and leaf kiss-squeaks. In Tuanan (Central Kalimantan, Indonesia), the acoustic frequency of unaided kiss-squeaks is negatively related to body size. The modified variants are correlated with perceived threat and are hypothesized to increase the perceived body size of the sender, as the use of a hand or leaves lowers the kiss-squeak’s acoustic frequency. We examined the use of these variants in the same context in another orangutan population of the same sub-species and with partially similar habitat at Cabang Panti (West Kalimantan, Indonesia). Identical analyses of data from this site provided similar results for unaided kiss-squeaks but dissimilar results for hand and leaf kiss-squeaks. Unaided kiss-squeaks at Cabang Panti were emitted as commonly and showed the same relationship to body size as in Tuanan. However, at Cabang Panti, hand kiss-squeaks were extremely rare, while leaf-use neither conveyed larger body size nor was related to perceived threat. These findings indicate functional discontinuity between the two sites and therefore imply functional arbitrariness of leaf kiss-squeaks. These results show for the first time the existence of animal signals involving call production with arbitrary function. Our findings are consistent with previous studies arguing that these orangutan call variants are socially learned and reconcile the role of gestures and calls within evolutionary theories based on common ancestry for speech and music. PMID:23861981

Population-specific use of the same tool-assisted alarm call between two wild orangutan populations (Pongo pygmaeus wurmbii) indicates functional arbitrariness [corrected].

PubMed

Lameira, Adriano R; Hardus, Madeleine E; Nouwen, Kim J J M; Topelberg, Eva; Delgado, Roberto A; Spruijt, Berry M; Sterck, Elisabeth H M; Knott, Cheryl D; Wich, Serge A

2013-01-01

Arbitrariness is an elementary feature of human language, yet seldom an object of comparative inquiry. While arbitrary signals for the same function are relatively frequent between animal populations across taxa, the same signal with arbitrary functions is rare and it remains unknown whether, in parallel with human speech, it may involve call production in animals. To investigate this question, we examined a particular orangutan alarm call - the kiss-squeak - and two variants - hand and leaf kiss-squeaks. In Tuanan (Central Kalimantan, Indonesia), the acoustic frequency of unaided kiss-squeaks is negatively related to body size. The modified variants are correlated with perceived threat and are hypothesized to increase the perceived body size of the sender, as the use of a hand or leaves lowers the kiss-squeak's acoustic frequency. We examined the use of these variants in the same context in another orangutan population of the same sub-species and with partially similar habitat at Cabang Panti (West Kalimantan, Indonesia). Identical analyses of data from this site provided similar results for unaided kiss-squeaks but dissimilar results for hand and leaf kiss-squeaks. Unaided kiss-squeaks at Cabang Panti were emitted as commonly and showed the same relationship to body size as in Tuanan. However, at Cabang Panti, hand kiss-squeaks were extremely rare, while leaf-use neither conveyed larger body size nor was related to perceived threat. These findings indicate functional discontinuity between the two sites and therefore imply functional arbitrariness of leaf kiss-squeaks. These results show for the first time the existence of animal signals involving call production with arbitrary function. Our findings are consistent with previous studies arguing that these orangutan call variants are socially learned and reconcile the role of gestures and calls within evolutionary theories based on common ancestry for speech and music.

A simulation analysis to characterize the dynamics of vaccinating behaviour on contact networks

PubMed Central

2009-01-01

Background Human behavior influences infectious disease transmission, and numerous "prevalence-behavior" models have analyzed this interplay. These previous analyses assumed homogeneously mixing populations without spatial or social structure. However, spatial and social heterogeneity are known to significantly impact transmission dynamics and are particularly relevant for certain diseases. Previous work has demonstrated that social contact structure can change the individual incentive to vaccinate, thus enabling eradication of a disease under a voluntary vaccination policy when the corresponding homogeneous mixing model predicts that eradication is impossible due to free rider effects. Here, we extend this work and characterize the range of possible behavior-prevalence dynamics on a network. Methods We simulate transmission of a vaccine-prevetable infection through a random, static contact network. Individuals choose whether or not to vaccinate on any given day according to perceived risks of vaccination and infection. Results We find three possible outcomes for behavior-prevalence dynamics on this type of network: small final number vaccinated and final epidemic size (due to rapid control through voluntary ring vaccination); large final number vaccinated and significant final epidemic size (due to imperfect voluntary ring vaccination), and little or no vaccination and large final epidemic size (corresponding to little or no voluntary ring vaccination). We also show that the social contact structure enables eradication under a broad range of assumptions, except when vaccine risk is sufficiently high, the disease risk is sufficiently low, or individuals vaccinate too late for the vaccine to be effective. Conclusion For populations where infection can spread only through social contact network, relatively small differences in parameter values relating to perceived risk or vaccination behavior at the individual level can translate into large differences in population-level outcomes such as final size and final number vaccinated. The qualitative outcome of rational, self interested behaviour under a voluntary vaccination policy can vary substantially depending on interactions between social contact structure, perceived vaccine and disease risks, and the way that individual vaccination decision-making is modelled. PMID:19476616

Moon Illusion and Emmert's Law.

PubMed

King, W L; Gruber, H E

1962-03-30

The perceived size of an afterimage varies with the part of the sky to which it is projected in a manner predictable from Emmert's Law and the appearance of the sky as a flattened dome. This effect is directly analogous to the moon illusion.

Perceived Cooling Using Asymmetrically-Applied Hot and Cold Stimuli.

PubMed

Manasrah, Ahmad; Crane, Nathan; Guldiken, Rasim; Reed, Kyle B

2017-01-01

Temperature perception is a highly nonlinear phenomenon with faster rates of change being perceived at much lower thresholds than slower rates. This paper presents a method that takes advantage of this nonlinear characteristic to generate a perception of continuous cooling even though the average temperature is not changing. The method uses multiple thermal actuators so that a few are cooling quickly while the rest of the actuators are heating slowly. The slowly-heating actuators are below the perceptual threshold temperature change and hence are not perceived, while the quickly-cooling actuators are above the perceptual temperature change, hence are perceived. As a result, a feeling of decreasing temperature was elicited, when in fact, there was no net change in the temperature of the skin. Three sets of judiciously designed experiments were conducted in this study, investigating the effects of actuator sizes, forearm measurement locations, patterns of actuator layout, and various heating/cooling time cycles. Our results showed that 19 out 21 participants perceived the continuous cooling effect as hypothesized. Our research indicates that the measurement location, heating/cooling cycle times, and arrangement of the actuators affect the perception of continuous cooling.

Depression Among Transgender Older Adults: General and Minority Stress.

PubMed

Hoy-Ellis, Charles P; Fredriksen-Goldsen, Karen I

2017-06-01

This study aims to (a) examine the direct and indirect effects internalized heterosexism, disclosure of gender identity, and perceived general stress in association with depression among transgender older adults; and (b) to assess the relative contribution of each relationship. Secondary analyses of data from a large community-based study of older sexual and gender minorities were conducted utilizing structural equation modeling with a subsample (n = 174) of transgender adults aged 50 to 86-years old. Disclosure of gender identity had no significant direct or indirect effects on either perceived general stress or depression. Internalized heterosexism did not have a direct effect on depression, but did have a significant indirect effect through perceived general stress. Finally, perceived general stress had an additional significant direct effect on depression, over and above internalized heterosexism. Total effect sizes appear to be considerable with standardized betas greater than 5.0. Perceived general stress and internalized heterosexism independently and cumulatively have significant direct and indirect effects on depression among transgender older adults. Implications for depression among transgender older adults and the role of community psychology are discussed. © Society for Community Research and Action 2017.

Perceived stress predicts altered reward and loss feedback processing in medial prefrontal cortex

PubMed Central

Treadway, Michael T.; Buckholtz, Joshua W.; Zald, David H.

2013-01-01

Stress is a significant risk factor for the development of psychopathology, particularly symptoms related to reward processing. Importantly, individuals display marked variation in how they perceive and cope with stressful events, and such differences are strongly linked to risk for developing psychiatric symptoms following stress exposure. However, many questions remain regarding the neural architecture that underlies inter-subject variability in perceptions of stressors. Using functional magnetic resonance imaging (fMRI) during a Monetary Incentive Delay (MID) paradigm, we examined the effects of self-reported perceived stress levels on neural activity during reward anticipation and feedback in a sample of healthy individuals. We found that subjects reporting more uncontrollable and overwhelming stressors displayed blunted neural responses in medial prefrontal cortex (mPFC) following feedback related to monetary gains as well monetary losses. This is consistent with preclinical models that implicate the mPFC as a key site of vulnerability to the noxious effects of uncontrollable stressors. Our data help translate these findings to humans, and elucidate some of the neural mechanisms that may underlie stress-linked risk for developing reward-related psychiatric symptoms. PMID:23730277

Orthognathic Surgery Has a Significant Effect on Perceived Personality Traits and Emotional Expressions.

PubMed

Mazzaferro, Daniel M; Wes, Ari M; Naran, Sanjay; Pearl, Rebecca; Bartlett, Scott P; Taylor, Jesse A

2017-11-01

The effects of orthognathic surgery go beyond objective cephalometric correction of facial and dental disproportion and malocclusion, respectively. The authors hypothesized that there is tangible improvement following surgery that alters publicly perceived personality traits and emotions. The authors used Amazon.com's Mechanical Turk (MTurk), a crowdsourcing tool, to determine how preoperative and postoperative images of orthognathic surgery patients were perceived on six personality traits and six emotional expressions based on posteroanterior and lateral photographs. Blinded respondents provided demographic information and were randomly assigned to one of two sets of 20 photographs (10 subjects before and after surgery). Data on 20 orthognathic surgery patients were collected from 476 individuals. The majority of participants were female (52.6 percent), 18 to 39 years old (67.9 percent), Caucasian (76.6 percent), had some college or technical training or graduated college (72.7 percent), and had an annual income between $20,000 and $99,999 (74.6 percent). A paired t test analysis found that subjects were perceived significantly more favorably after orthognathic surgery in 12 countenance categories: more dominant, trustworthy, friendly, intelligent, attractive, and happy; and also less threatening, angry, surprised, sad, afraid, and disgusted (p < 0.05). Raters with the highest annual income perceived a greater magnitude of dominance after surgery than those earning less (p < 0.001). There is significant improvement in the countenance of patients after orthognathic surgery, with both perceived personality traits and emotions deemed more favorable. Additional work is needed to better understand the physiologic underpinnings of such findings. Crowdsourcing technology offers a unique opportunity for surgeons to gather data regarding laypeople's perceptions of surgical outcomes in areas such as orthognathic surgery.

Effects of sweet flavorings and nicotine on the appeal and sensory properties of e-cigarettes among young adult vapers: Application of a novel methodology.

PubMed

Goldenson, Nicholas I; Kirkpatrick, Matthew G; Barrington-Trimis, Jessica L; Pang, Raina D; McBeth, Julia F; Pentz, Mary Ann; Samet, Jonathan M; Leventhal, Adam M

2016-11-01

Product characteristics that impact e-cigarette appeal by altering the sensory experience of vaping need to be identified to formulate evidence-based regulatory policies. While products that contain sweet flavorings and produce a "throat hit" (i.e., desirable airway irritation putatively caused by nicotine) are anecdotally cited as desirable reasons for vaping among young adults, experimental evidence of their impact on user appeal is lacking. This experiment applied a novel laboratory protocol to assess whether: (1) sweet flavorings and nicotine affect e-cigarette appeal; (2) sweet flavorings increase perceived sweetness; (3) nicotine increases throat hit; and (4) perceived sweetness and throat hit are associated with appeal. Young adult vapers (N=20; age 19-34) self-administered 20 standardized doses of aerosolized e-cigarette solutions varied according to a 3 flavor (sweet [e.g., cotton candy] vs. non-sweet [e.g., tobacco-flavored] vs. flavorless)×2 nicotine (6mg/mL nicotine vs. 0mg/mL [placebo]) double-blind, cross-over design. Participants rated appeal (liking, willingness to use again and perceived monetary value), perceived sweetness and throat hit strength after each administration. Sweet-flavored (vs. non-sweet and flavorless) solutions produced greater appeal and perceived sweetness ratings. Nicotine produced greater throat hit ratings than placebo, but did not significantly increase appeal nor interact with flavor effects on appeal. Controlling for flavor and nicotine, perceived sweetness was positively associated with appeal ratings; throat hit was not positively associated with appeal. Further identification of compounds in e-cigarette solutions that enhance sensory perceptions of sweetness, appeal, and utilization of e-cigarettes are warranted to inform evidence-based regulatory policies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effects of Sweet Flavorings and Nicotine on the Appeal and Sensory Properties of e-Cigarettes Among Young Adult Vapers: Application of a Novel Methodology*

PubMed Central

Goldenson, Nicholas I.; Kirkpatrick, Matthew G.; Barrington-Trimis, Jessica L.; Pang, Raina D.; McBeth, Julia F.; Pentz, Mary Ann; Samet, Jonathan M.; Leventhal, Adam M.

2016-01-01

Introduction Product characteristics that impact e-cigarette appeal by altering the sensory experience of vaping need to be identified to formulate evidence-based regulatory policies. While products that contain sweet flavorings and produce a “throat hit” (i.e., desirable airway irritation putatively caused by nicotine) are anecdotally cited as desirable reasons for vaping among young adults, experimental evidence of their impact on user appeal is lacking. This experiment applied a novel laboratory protocol to assess whether: (1) sweet flavorings and nicotine affect e-cigarette appeal; (2) sweet flavorings increase perceived sweetness; (3) nicotine increases throat hit; and (4) perceived sweetness and throat hit are associated with appeal. Methods Young adult vapers (N=20; age 19–34) self-administered 20 standardized doses of aerosolized e-cigarette solutions varied according to a 3 flavor (sweet [e.g., cotton candy] vs. non-sweet [e.g., tobacco-flavored] vs. flavorless) × 2 nicotine (6 mg/mL nicotine vs. 0 mg/mL [placebo]) double-blind, cross-over design. Participants rated appeal (liking, willingness to use again and perceived monetary value), perceived sweetness and throat hit strength after each administration. Results Sweet-flavored (vs. non-sweet and flavorless) solutions produced greater appeal and perceived sweetness ratings. Nicotine produced greater throat hit ratings than placebo, but did not significantly increase appeal nor interact with flavor effects on appeal. Controlling for flavor and nicotine, perceived sweetness was positively associated with appeal ratings; throat hit was not positively associated with appeal. Conclusions Further identification of compounds in e-cigarette solutions that enhance sensory perceptions of sweetness, appeal, and utilization of e-cigarettes are warranted to inform evidence-based regulatory policies. PMID:27676583

Blanching of paint and varnish layers in easel paintings: contribution to the understanding of the alteration

NASA Astrophysics Data System (ADS)

Genty-Vincent, Anaïs; Eveno, Myriam; Nowik, Witold; Bastian, Gilles; Ravaud, Elisabeth; Cabillic, Isabelle; Uziel, Jacques; Lubin-Germain, Nadège; Menu, Michel

2015-11-01

The blanching of easel paintings can affect the varnish layer and also the paint layer with a blurring effect. The understanding of the physicochemical and optical phenomena involved in the whitening process remains an important challenge for the painting conservation. A set of ca. 50 microsamples from French, Flemish, and Italian blanched oil paintings, from sixteenth to nineteenth century, have been collected for in deep investigations. In parallel, the reproduction of the alteration was achieved by preparing some paint layers according to historical treatises and altering them in a climatic chamber in a humid environment or directly by immersing in ultrapure water. The observation of raw samples with a field-emission gun scanning electron microscope revealed for the first time that the altered layers have an unexpected highly porous structure with a pore size ranging from ca. 40 nm to 2 μm. The formation mechanism of these pores should mostly be physical as the supplementary analyses (Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry) do not reveal any noticeable molecular modification. Considering the tiny size of the pores, the alteration can be explained by the Rayleigh or Mie light scattering.

Racial bias in judgments of physical size and formidability: From size to threat.

PubMed

Wilson, John Paul; Hugenberg, Kurt; Rule, Nicholas O

2017-07-01

Black men tend to be stereotyped as threatening and, as a result, may be disproportionately targeted by police even when unarmed. Here, we found evidence that biased perceptions of young Black men's physical size may play a role in this process. The results of 7 studies showed that people have a bias to perceive young Black men as bigger (taller, heavier, more muscular) and more physically threatening (stronger, more capable of harm) than young White men. Both bottom-up cues of racial prototypicality and top-down information about race supported these misperceptions. Furthermore, this racial bias persisted even among a target sample from whom upper-body strength was controlled (suggesting that racial differences in formidability judgments are a product of bias rather than accuracy). Biased formidability judgments in turn promoted participants' justifications of hypothetical use of force against Black suspects of crime. Thus, perceivers appear to integrate multiple pieces of information to ultimately conclude that young Black men are more physically threatening than young White men, believing that they must therefore be controlled using more aggressive measures. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Does relative out-group size in neighborhoods drive down associational life of Whites in the U.S.? Testing constrict, conflict and contact theories.

PubMed

Savelkoul, Michael; Hewstone, Miles; Scheepers, Peer; Stolle, Dietlind

2015-07-01

We test whether a larger percentage of non-Whites in neighborhoods decreases associational involvement and build on earlier research in three ways. First, we explicitly consider the ethnic composition of organizations, distinguishing involvement in bridging (with out-group members) and bonding (only in-group members) organizations. Second, we start from constrict theory and test competing sets of predictions derived from conflict and contact theories to explain these relationships. Third, we examine whether relative out-group size affects involvement in different types of voluntary organizations equally. Using data from the 2005 U.S. 'Citizenship, Involvement, Democracy' survey, the percentage of non-Whites in neighborhoods is largely unrelated with associational involvement or perceived ethnic threat. However, perceiving ethnic threat is consistently negatively related with involvement in bridging organizations. Simultaneously, a larger percentage of non-Whites fosters intergroup contact, which is negatively related with perceptions of ethnic threat and involvement in bonding leisure organizations. Our results shed more light on the relationship between the relative out-group size in neighborhoods and associational involvement as well as underlying explanations for this link. Copyright © 2015 Elsevier Inc. All rights reserved.

Head-body ratio as a visual cue for stature in people and sculptural art.

PubMed

Mather, George

2010-01-01

Body size is crucial for determining the outcome of competition for resources and mates. Many species use acoustic cues to measure caller body size. Vision is the pre-eminent sense for humans, but visual depth cues are of limited utility in judgments of absolute body size. The reliability of internal body proportion as a potential cue to stature was assessed with a large sample of anthropometric data, and the ratio of head height to body height (HBR) was found to be highly correlated with stature. A psychophysical experiment was carried out to investigate whether the cue actually influences stature judgments. Participants were shown pairs of photographs of human figures in which HBR had been manipulated systematically, and asked to select the figure that appeared taller. Results showed that figures with a relatively small HBR were consistently perceived as taller than figures with a relatively large HBR. Many classical statues such as Michelangelo's David depart from the classical proportions defined in Leonardo's Vitruvian Man. A supplementary experiment showed that perceived stature in classical statues also depends on HBR. Michelangelo's David was created with the HBR of a man 165 cm (5 ft 5 in) tall.

Brief report: altered horizontal binding of single dots to coherent motion in autism.

PubMed

David, Nicole; Rose, Michael; Schneider, Till R; Vogeley, Kai; Engel, Andreas K

2010-12-01

Individuals with autism often show a fragmented way of perceiving their environment, suggesting a disorder of information integration, possibly due to disrupted communication between brain areas. We investigated thirteen individuals with high-functioning autism (HFA) and thirteen healthy controls using the metastable motion quartet, a stimulus consisting of two dots alternately presented at four locations of a hypothetical square, thereby inducing an apparent motion percept. This percept is vertical or horizontal, the latter requiring binding of motion signals across cerebral hemispheres. Decreasing the horizontal distance between dots could facilitate horizontal percepts. We found evidence for altered horizontal binding in HFA: Individuals with HFA needed stronger facilitation to experience horizontal motion. These data are interpreted in light of reduced cross-hemispheric communication.

Witnessing a body in decline: Men's and women's perceptions of an altered physical appearance.

PubMed

Hilário, Ana Patrícia

2016-01-01

There has been a tendency within the literature to ignore how men and women who are very ill and at the end of life perceive and experience their visibly altered bodies. This article aims to provide new insights about this matter. A qualitative research approach was adopted. In-depth interviews were conducted with 10 hospice patients, 20 family members, and 20 members of hospice staff. Findings reveal that because of masculine and feminine norms, physical appearance is more a matter of concern to women than to men who are close to death. This contradicts theories that suggest that patients experience a disinvestment on their sense of masculinity and femininity alongside the process of bodily deterioration and decay prior impending potential death.

Reduced sensitivity for visual textures affects judgments of shape-from-shading and step-climbing behaviour in older adults.

PubMed

Schofield, Andrew J; Curzon-Jones, Benjamin; Hollands, Mark A

2017-02-01

Falls on stairs are a major hazard for older adults. Visual decline in normal ageing can affect step-climbing ability, altering gait and reducing toe clearance. Here we show that a loss of fine-grained visual information associated with age can affect the perception of surface undulations in patterned surfaces. We go on to show that such cues affect the limb trajectories of young adults, but due to their lack of sensitivity, not that of older adults. Interestingly neither the perceived height of a step nor conscious awareness is altered by our visual manipulation, but stepping behaviour is, suggesting that the influence of shape perception on stepping behaviour is via the unconscious, action-centred, dorsal visual pathway.

A simple but powerful theory of the moon illusion.

PubMed

Baird, J C; Wagner, M; Fuld, K

1990-08-01

Modification of Restle's theory (1970) explains the moon illusion and related phenomena on the basis of three principles: (1) The apparent sizes of objects are their perceived visual angles. (2) The apparent size of the moon is determined by the ratio of the angular extent of the moon relative to the extents subtended by objects composing the surrounding context, such as the sky and things on the ground. (3) The visual extents subtended by common objects of a constant physical size decrease systematically with increasing distance from the observer. Further development of this theory requires specification of both the components of the surrounding context and their relative importance in determining the apparent size and distance of the moon.

Silymarin improves the behavioural, biochemical and histoarchitecture alterations in focal ischemic rats: a comparative evaluation with piracetam and protocatachuic acid.

PubMed

Muley, Milind M; Thakare, Vishnu N; Patil, Rajesh R; Kshirsagar, Ajay D; Naik, Suresh R

2012-08-01

Comparative neuroprotective potential of silymarin, piracetam and protocatechuic acid ethyl ester (PCA) was evaluated in focal ischemic rats. Various pharmacological, biochemical (lipid peroxidation, reduced glutathione, catalase, nitrite content, brain water content) and behavioural (memory impairment, motor control, neurological score) including infarct size and histopathological alterations were evaluated. Silymarin (200mg/kg) and PCA treatment significantly improved behavioural, biochemical and histopathological changes, and reduced water content and infarct size. However, piracetam only improved behavioural and histopathological changes, reduced water content and infarct size. The findings indicate that silymarin exhibits neuroprotective activity better than PCA and piracetam in focal ischemia/reperfusion reflected by its better restoration of behavioural and antioxidant profile. Copyright © 2012 Elsevier Inc. All rights reserved.

Water in the early solar system: Mid-infrared studies of aqueous alteration on asteroids.

NASA Astrophysics Data System (ADS)

McAdam, Margaret M.; Sunshine, Jessica M.; Kelley, Michael S.; Trilling, David E.

2017-10-01

This work investigates the distribution of water in the early Solar System by connecting asteroids to carbonaceous chondrite meteorites using spectroscopy. Aqueous alteration or the chemical reaction between liquid water and silicates on the parent asteroid, has extensively affected several groups of carbonaceous chondrites. The degree of alteration or amount of hydrated minerals produced depends on a number of factors including the abundance of coaccreted water-ice, the internal distribution of water in the parent body and the setting of alteration (e.g., open vs. closed setting). Despite this complexity which is still under investigation, the mineralogical changes produced by aqueous alteration are well understood (e.g., Howard et al., 2015). The mid-infrared spectral region has been shown to be a tool for estimating the degree of alteration of asteroids and meteorites remotely (McAdam et al., 2015). Specifically, mid-infrared spectral features changes continuously with degree of alteration. In this region meteorites can be categorized into four groups based on their spectral characteristics: anhydrous, less altered, intermediately altered and highly altered. We present the estimated degrees of alteration for 73 main belt asteroids using these results. Hydrated minerals appear to be widespread in the main belt and asteroids have variable degrees of alteration. There does not appear to be any relationship between the estimated degree of alteration and size, albedo or heliocentric distance. This indicates that water-ice must have been a significant component of the solar nebula in the 2-5 AU region during the time of carbonaceous chondrite accretion (~2.7-4 Ma post-CAI formation; Sugiura and Fujiya, 2014). The snow-line therefore must have been in this region during this epoch. Furthermore, local heterogeneities of water-ice were likely common since asteroids of all sizes and heliocentric distances may exhibit any degree from anhydrous to highly altered. Additionally, asteroids that have been shown to have water-ice on their surfaces (e.g., Takir and Emery, 2012) appear to have hydrated minerals. This indicates that while these asteroids have water-ice, its presence did not prevent aqueous alteration.

7 CFR 999.1 - Regulation governing the importation of dates.

Code of Federal Regulations, 2012 CFR

2012-01-01

... includes dates coated with a substance materially altering their color. (5) Dates prepared or preserved... altering their color, or dates prepared for incorporation into a product by chopping, slicing, or other... hydration, the dates possess a reasonably good color, are reasonably uniform in size, are reasonably free...

7 CFR 999.1 - Regulation governing the importation of dates.

Code of Federal Regulations, 2011 CFR

2011-01-01

... includes dates coated with a substance materially altering their color. (5) Dates prepared or preserved... altering their color, or dates prepared for incorporation into a product by chopping, slicing, or other... hydration, the dates possess a reasonably good color, are reasonably uniform in size, are reasonably free...

Ultrasound and phenotypic measures of the reproductive tract of prepubertal gilts selected for increased uterine capacity

USDA-ARS?s Scientific Manuscript database

Direct selection for uterine capacity (UC) increases litter size without altering ovulation rate. A method to estimate UC in developing gilts would be beneficial for commercial selection strategies. We tested the hypothesis that selection for UC alters phenotypic characteristics of the reproductiv...

Effect of 3 Different Applications of Kinesio Taping Denko® on Electromyographic Activity: Inhibition or Facilitation of the Quadriceps of Males During Squat Exercise

PubMed Central

Serrão, Júlio C.; Mezêncio, Bruno; Claudino, João G.; Soncin, Rafael; Miyashiro, Pedro L. Sampaio; Sousa, Eric P.; Borges, Eduardo; Zanetti, Vinícius; Phillip, Igor; Mochizuki, Luiz; Amadio, Alberto C.

2016-01-01

Kinesio taping consists of a technique which uses the application of an elastic adhesive tape. It has become a widely used rehabilitation modality for the prevention and treatment of musculoskeletal disorders. The objective of this study was to verify the effect of the application of Kinesio Taping Denko® in three conditions (facilitation, inhibition, and placebo) on the electromyographic activity of the quadriceps and hamstrings muscles on facilitating or inhibiting the muscle function and on the perceived exertion during the barbell back squat exercise in healthy male subjects. Methods: It was a randomized, single-blinded and controlled study in which 18 males (28.0 ± 6.7 years old; 85.8 ± 8.2 kg mass; 1.80 ± 0.07 m tall; 0.97 ± 0.04 m lower limb length) performed barbell back squat exercise with different conditions of Kinesio Taping Denko® applications: Facilitation, inhibition and placebo. Previous to the mentioned conditions, all individuals were assessed without applying kinesio Taping Denko® during the exercise. OMNI scale was used after each set for perceived exertion evaluation. No differences (p < 0.05) in the electromyographic activity of the biceps femoris, vastus lateralis and vastus medialis or OMNI scale were recorded under any conditions. The results show that the kinesio taping denko®may not alter the magnitude of the electromyography activity of vastus lateralis, vastus medialis, and biceps femoris during the squat exercise. Furthermore, the perceived exertion was not affected by the kinesio taping denko® application. Key points Researchers involved in collecting data in this study have no financial or personal interest in the outcome of results or the sponsor. The perceived exertion was not affected by the kinesiology taping application. Kinesiology taping application may not alter the magnitude of EMG activity of vastuslateralis, vastusmedialis, and biceps femoris during the barbell back squat exercise. Electromyographic activity of kinesiology taping application on other muscle groups and in other cohorts, such as healthy elderly subjects and patients under a rehabilitation program require further investigation. PMID:27803618

Bilateral Symmetry of Distortions of Tactile Size Perception.

PubMed

Longo, Matthew R; Ghosh, Arko; Yahya, Tasneem

2015-01-01

The perceived distance between touches on the limbs is generally bigger for distances oriented across the width of the limb than for distances oriented along the length of the limb. The present study aimed to investigate the coherence of such distortions of tactile size perception across different skin surfaces. We investigated distortions of tactile size perception on the dorsal and palmar surfaces of both the left and right hands as well as the forehead. Participants judged which of two tactile distances felt larger. One distance was aligned with the proximodistal axis (along the body), the other with the mediolateral axis (across the body). Clear distortions were found on all five skin surfaces, with stimuli oriented across the width of the body being perceived as farther apart than those oriented along the length of the body. Consistent with previous results, distortions were smaller on the palmar than on the dorsal hand surface. Distortion on the forehead was intermediate between the dorsal and palmar surfaces. There were clear correlations between distortion on the left and right hands, for both the dorsal and palmar skin surfaces. In contrast, within each hand, there was no significant correlation between the two skin surfaces. Distortion on the forehead was not significantly correlated with that on any of the other skin surfaces. These results provide evidence for bilaterally symmetric representations underlying tactile size perception. © The Author(s) 2015.

Programming of endocrine mechanisms of cardiovascular control and growth.

PubMed

Green, L R

2001-01-01

Several epidemiologic studies have linked size at birth to health in adult life. One school of thought centers on the part that periconceptual or intrauterine events play in this relationship. The idea is that an event, or several events, during critical periods of development can program, or permanently alter, fetal physiology resulting in altered size at birth and subsequent adult disease, including that of the cardiovascular system. Maternal diet or body composition at the time of conception can influence placental development and subsequent transfer of nutrients and substrates to the fetus. Alterations to the maternal diet or body composition throughout gestation are then seen as challenges that are superimposed on this backdrop of periconceptual events. One task is to find an animal model that replicates the major features of the epidemiologic data: for adult cardiovascular disease this would be altered fetal size and the development of postnatal hypertension. In addition, a critical issue is to investigate the mechanisms underlying this Fetal Origins of Adult Disease hypothesis. The multiple mechanisms that constitute fetal cardiovascular responses to hypoxia in late gestation at neuronal, endocrine, and local tissue levels have been studied extensively, and there is evidence from several different experimental paradigms that these control mechanisms can be programmed by intrauterine challenges. This review synthesizes the current knowledge in this area and considers how the programming of cardiovascular control relates to fetal growth.

Demystifying first-cost green building premiums in healthcare.

PubMed

Houghton, Adele; Vittori, Gail; Guenther, Robin

2009-01-01

This study assesses the extent of "first-cost green building construction premiums" in the healthcare sector based on data submitted by and interviews with 13 current LEED-certified and LEED-registered healthcare project teams, coupled with a literature survey of articles on the topics of actual and perceived first-cost premiums associated with green building strategies. This analysis covers both perceived and realized costs across a range of projects in this sector, leading to the following conclusions: Construction first-cost premiums may be lower than is generally perceived, and they appear to be independent of both building size and level of "green" achievement; projects are using financial incentives and philanthropy to drive higher levels of achievement; premiums are decreasing over time; and projects are benefiting from improvements in health and productivity which, although difficult to monetize, are universally valued.

Perceived racism and mental health among Black American adults: a meta-analytic review.

PubMed

Pieterse, Alex L; Todd, Nathan R; Neville, Helen A; Carter, Robert T

2012-01-01

The literature indicates that perceived racism tends to be associated with adverse psychological and physiological outcomes; however, findings in this area are not yet conclusive. In this meta-analysis, we systematically reviewed 66 studies (total sample size of 18,140 across studies), published between January 1996 and April 2011, on the associations between racism and mental health among Black Americans. Using a random-effects model, we found a positive association between perceived racism and psychological distress (r = .20). We found a moderation effect for psychological outcomes, with anxiety, depression, and other psychiatric symptoms having a significantly stronger association than quality of life indicators. We did not detect moderation effects for type of racism scale, measurement precision, sample type, or type of publication. Implications for research and practice are discussed. (c) 2012 APA, all rights reserved).

Finding the faithless: perceived atheist prevalence reduces anti-atheist prejudice.

PubMed

Gervais, Will M

2011-04-01

Although prejudice is typically positively related to relative outgroup size, four studies found converging evidence that perceived atheist prevalence reduces anti-atheist prejudice. Study 1 demonstrated that anti-atheist prejudice among religious believers is reduced in countries in which atheists are especially prevalent. Study 2 demonstrated that perceived atheist prevalence is negatively associated with anti-atheist prejudice. Study 3 demonstrated a causal relationship: Reminders of atheist prevalence reduced explicit distrust of atheists. These results appeared distinct from intergroup contact effects. Study 4 demonstrated that prevalence information decreased implicit atheist distrust. The latter two experiments provide the first evidence that mere prevalence information can reduce prejudice against any outgroup. These findings offer insights about anti-atheist prejudice, a poorly understood phenomenon. Furthermore, they suggest both novel directions for future prejudice research and potential interventions that could reduce a variety of prejudices.

The influence of subjective norm on intention to use of learning management system among Malaysian higher education students

NASA Astrophysics Data System (ADS)

Baleghi-Zadeh, Sousan; Ayub, Ahmad Fauzi Mohd; Mahmud, Rosnaini; Daud, Shaffe Mohd

2014-12-01

In recent years, the use of learning management system by universities has been increasingly growing. However, the results of several studies have revealed that students do not fully use the information systems. The present study proposes a model which investigates the influence of three constructs of perceived ease of use, perceived usefulness, and subjective norm on behavior intention to use of learning management system. The sample size was 216 Malaysian undergraduate students. The results of the study revealed that the proposed model accounts for 31.1 % variance of behavior intention to use.

Shifts in the climate space of temperate cyprinid fishes due to climate change are coupled with altered body sizes and growth rates.

PubMed

Ruiz-Navarro, Ana; Gillingham, Phillipa K; Britton, J Robert

2016-09-01

Predictions of species responses to climate change often focus on distribution shifts, although responses can also include shifts in body sizes and population demographics. Here, shifts in the distributional ranges ('climate space'), body sizes (as maximum theoretical body sizes, L∞) and growth rates (as rate at which L∞ is reached, K) were predicted for five fishes of the Cyprinidae family in a temperate region over eight climate change projections. Great Britain was the model area, and the model species were Rutilus rutilus, Leuciscus leuciscus, Squalius cephalus, Gobio gobio and Abramis brama. Ensemble models predicted that the species' climate spaces would shift in all modelled projections, with the most drastic changes occurring under high emissions; all range centroids shifted in a north-westerly direction. Predicted climate space expanded for R. rutilus and A. brama, contracted for S. cephalus, and for L. leuciscus and G. gobio, expanded under low-emission scenarios but contracted under high emissions, suggesting the presence of some climate-distribution thresholds. For R. rutilus, A. brama, S. cephalus and G. gobio, shifts in their climate space were coupled with predicted shifts to significantly smaller maximum body sizes and/or faster growth rates, aligning strongly to aspects of temperature-body size theory. These predicted shifts in L∞ and K had considerable consequences for size-at-age per species, suggesting substantial alterations in population age structures and abundances. Thus, when predicting climate change outcomes for species, outputs that couple shifts in climate space with altered body sizes and growth rates provide considerable insights into the population and community consequences, especially for species that cannot easily track their thermal niches. © 2016 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Climate change alters the reproductive phenology and investment of a lacustrine fish, the three-spine stickleback.

PubMed

Hovel, Rachel A; Carlson, Stephanie M; Quinn, Thomas P

2017-06-01

High-latitude lakes are particularly sensitive to the effects of global climate change, demonstrating earlier ice breakup, longer ice-free seasons, and increased water temperatures. Such physical changes have implications for diverse life-history traits in taxa across entire lake food webs. Here, we use a five-decade time series from an Alaskan lake to explore effects of climate change on growth and reproduction of a widely distributed lacustrine fish, the three-spine stickleback (Gasterosteus aculeatus). We used multivariate autoregressive state-space (MARSS) models to describe trends in the mean length for multiple size classes and to explore the influence of physical (date of ice breakup, surface water temperature) and biological (density of con- and heterospecifics) factors. As predicted, mean size of age 1 and older fish at the end of the growing season increased across years with earlier ice breakup and warmer temperatures. In contrast, mean size of age 0 fish decreased over time. Overall, lower fish density and warmer water temperatures were associated with larger size for all cohorts. Earlier ice breakup was associated with larger size for age 1 and older fish but, paradoxically, with smaller size of age 0 fish. To explore this latter result, we used mixing models on age 0 size distributions, which revealed an additional cohort in years with early ice breakup, lowering the mean size of age 0 fish. Moreover, early ice breakup was associated with earlier breeding, evidenced by earlier capture of age 0 fish. Our results suggest that early ice breakup altered both timing and frequency of breeding; three-spine stickleback spawned earlier and more often in response to earlier ice breakup date. While previous studies have shown the influence of changing conditions in northern lakes on breeding timing and growth, this is the first to document increased breeding frequency, highlighting another pathway by which climate change can alter the ecology of northern lakes. © 2016 John Wiley & Sons Ltd.

The influence of attention toward facial expressions on size perception.

PubMed

Choi, Jeong-Won; Kim, Kiho; Lee, Jang-Han

2016-01-01

According to the New Look theory, size perception is affected by emotional factors. Although previous studies have attempted to explain the effects of both emotion and motivation on size perception, they have failed to identify the underlying mechanisms. This study aimed to investigate the underlying mechanisms of size perception by applying attention toward facial expressions using the Ebbinghaus illusion as a measurement tool. The participants, female university students, were asked to judge the size of a target stimulus relative to the size of facial expressions (i.e., happy, angry, and neutral) surrounding the target. The results revealed that the participants perceived angry and neutral faces to be larger than happy faces. This finding indicates that individuals pay closer attention to neutral and angry faces than happy ones. These results suggest that the mechanisms underlying size perception involve cognitive processes that focus attention toward relevant stimuli and block out irrelevant stimuli.

Perceiving Affordances for Fitting through Apertures

ERIC Educational Resources Information Center

Ishak, Shaziela; Adolph, Karen E.; Lin, Grace C.

2008-01-01

Affordances--possibilities for action--are constrained by the match between actors and their environments. For motor decisions to be adaptive, affordances must be detected accurately. Three experiments examined the correspondence between motor decisions and affordances as participants reached through apertures of varying size. A psychophysical…

Perceived social isolation is associated with altered functional connectivity in neural networks associated with tonic alertness and executive control.

PubMed

Layden, Elliot A; Cacioppo, John T; Cacioppo, Stephanie; Cappa, Stefano F; Dodich, Alessandra; Falini, Andrea; Canessa, Nicola

2017-01-15

Perceived social isolation (PSI), colloquially known as loneliness, is associated with selectively altered attentional, cognitive, and affective processes in humans, but the neural mechanisms underlying these adjustments remain largely unexplored. Behavioral, eye tracking, and neuroimaging research has identified associations between PSI and implicit hypervigilance for social threats. Additionally, selective executive dysfunction has been evidenced by reduced prepotent response inhibition in social Stroop and dichotic listening tasks. Given that PSI is associated with pre-attentional processes, PSI may also be related to altered resting-state functional connectivity (FC) in the brain. Therefore, we conducted the first resting-state fMRI FC study of PSI in healthy young adults. Five-minute resting-state scans were obtained from 55 participants (31 females). Analyses revealed robust associations between PSI and increased brain-wide FC in areas encompassing the right central operculum and right supramarginal gyrus, and these associations were not explained by depressive symptomatology, objective isolation, or demographics. Further analyses revealed that PSI was associated with increased FC between several nodes of the cingulo-opercular network, a network known to underlie the maintenance of tonic alertness. These regions encompassed the bilateral insula/frontoparietal opercula and ACC/pre-SMA. In contrast, FC between the cingulo-opercular network and right middle/superior frontal gyrus was reduced, a finding associated with diminished executive function in prior literature. We suggest that, in PSI, increased within-network cingulo-opercular FC may be associated with hypervigilance to social threat, whereas reduced right middle/superior frontal gyrus FC to the cingulo-opercular network may be associated with diminished impulse control. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of caffeine and aspirin on light resistance training performance, perceived exertion, and pain perception.

PubMed

Hudson, Geoffrey M; Green, J Matt; Bishop, Phillip A; Richardson, Mark T

2008-11-01

This study compared independent effects of caffeine and aspirin on muscular endurance (repetitions), heart rate (HR), perceived exertion (RPE), and perceived pain index (PPI) during light resistance training bouts performed to volitional failure. It was hypothesized that the hypoalgesic properties of these ergogenic aids would decrease pain perception and potentially result in enhanced performance. College-aged men (n = 15) participated in a within-subjects, double-blind study with three independent, counterbalanced sessions wherein aspirin (10 mg x kg(-1)), caffeine (6 mg x kg(-1)), or matched placebo were ingested 1 hour before exercise, and RPE, HR, PPI, and repetitions (per set and total per exercise) were recorded at 100% of individual, predetermined, 12-repetition maximum for leg extensions (LE) and seated arm curls (AC). Repeated-measures analyses of variance were used for between-trial comparisons. Caffeine resulted in significantly greater (p < 0.05) HR (LE and AC), total repetitions (LE), and repetitions in set 1 (LE and AC) compared with aspirin and placebo. Aspirin resulted in significantly higher PPI in set 1 (LE). In LE, 47% of participants' performance exceeded the predetermined effect size (>or= 5 repetitions) for total repetitions, with 53% exceeding the effect size (>or= 2 repetitions) for repetitions in set 1 with caffeine (vs. placebo). In AC, 53% (total repetitions) and 47% (set 1 repetitions) of participants exceeded effect sizes with caffeine (vs. placebo), with only 13% experiencing decrements in performance (total repetitions). Aspirin also produced a higher PPI and RPE overall and in set 1 (vs. placebo). This study demonstrates that caffeine significantly enhanced resistance training performance in LE and AC, whereas aspirin did not. Athletes may improve their resistance training performance by acute ingestion of caffeine. As with most ergogenic aids, our analyses indicate that individual responses vary greatly.

Correlates of Perceived Social Support in Chinese Adult Child Caregivers of Parent Stroke Survivors.

PubMed

Pan, Yuqin; Jones, Patricia S

2017-10-01

Prevalence of stroke and traditional filial responsibility involve adult children in caregiving to their parent stroke survivors in China. Support resources are insufficient because of the shrinking size of family and the underdeveloped support system. The aim of this study was to identify the correlates of perceived social support among adult child caregivers of parent stroke survivors in China. A cross-sectional correlational design was used in this study. A nonproportional quota sample of 126 adult child caregivers was recruited from Zhejiang Province, China. Data were collected at either the hospital stroke units or the respondents' homes using structured questionnaires of caregiving dyadic demographics and caregiving characteristics, 14-item Activities of Daily Living, 15-item Mutuality Scale, and 12-item Multidimensional Scale of Perceived Social Support. SPSS 17.0 was used for analysis. Caregivers' mutuality, education, full employment or being retired, monthly income, having a co-carer, and having a father as the care receiver were significantly positively associated with caregivers' perceived social support. However, mutuality was not significantly associated with caregivers' perceived social support after the other factors were adjusted. Adult child caregivers with higher levels of mutuality, education, or monthly income; who are fully employed or are retired; who have a co-carer; or who are caring for a father perceived more social support. Nursing strategies and social policies need to be directed to enhance caregiver mutuality and support caregiving efforts.

What are other parents saying? Perceived parental communication norms and the relationship between alcohol-specific parental communication and college student drinking

PubMed Central

Napper, Lucy E.; Hummer, Justin F.; Lac, Andrew; LaBrie, Joseph W.

2013-01-01

This study examined parents’ normative perceptions of other college parents’ alcohol-specific communication, and how parents’ perceived communication norms and alcohol-specific communication relate to student drinking outcomes. A sample of 457 student-parent dyads were recruited from a mid-size university. Students completed web-based assessments of alcohol-related attitudes and behaviors. Parents completed alcohol-specific measures of communication norms and parent-child communication, including communication content (i.e., targeted communication) and frequency of communication. Results indicated that parents overestimated how much other parents talked to their college students about the frequency and quantity of alcohol use, but underestimated how often parents initiated conversations about alcohol. In a path model, perceived communication norms positively predicted both targeted communication and frequency of communication. Perceived communication norms and targeted communication negatively predicted students’ attitude toward alcohol use. In contrast, more frequent communication predicted students holding more approving attitudes toward alcohol. The relationship between parents’ perceived communication norms and students’ drinking behaviors was mediated by the parental communication variables and student attitudes. Tests of indirect effects were undertaken to examine meditational processes. The findings underscore relations involving parental perceived communication norms and parents’ own alcohol communication and their children’s drinking outcomes. The complex relationships of different types of parental communication and student outcomes warrant further research. PMID:24128293

Ontogenetic and evolutionary effects of predation and competition on nine-spined stickleback (Pungitius pungitius) body size.

PubMed

Välimäki, Kaisa; Herczeg, Gábor

2012-07-01

1. Individual- and population-level variation in body size and growth often correlates with many fitness traits. Predation and food availability are expected to affect body size and growth as important agents of both natural selection and phenotypic plasticity. How differences in predation and food availability affect body size/growth during ontogeny in populations adapted to different predation and competition regimes is rarely studied. 2. Nine-spined stickleback (Pungitius pungitius) populations originating from habitats with varying levels of predation and competition are known to be locally adapted to their respective habitats in terms of body size and growth. Here, we studied how different levels of perceived predation risk and competition during ontogeny affect the reaction norms of body size and growth in (i) marine and pond populations adapted to different levels of predation and competition and (ii) different sexes. We reared nine-spined stickleback in a factorial experiment under two levels of perceived predation risk (present/absent) and competition (high/low food supply). 3. We found divergence in the reaction norms at two levels: (i) predation-adapted marine stickleback had stronger reactions to predatory cues than intraspecific competition-adapted pond stickleback, the latter being more sensitive to available food than the marine fish and (ii) females reacting more strongly to the treatments than males. 4. The repeated, habitat-dependent nature of the differences suggests that natural selection is the agent behind the observed patterns. Our results suggest that genetic adaptation to certain environmental factors also involves an increase in the range of expressible phenotypic plasticity. We found support for this phenomenon at two levels: (i) across populations driven by habitat type and (ii) within populations driven by sex. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

Comprehensive Nuclear-Test-Ban Treaty: Updated ’Safeguards’ and Net Assessments

DTIC Science & Technology

2009-06-03

measures that this nation can take unilaterally within the treaty to protect its nuclear security. To compensate for “disadvantages and risk” they...and strategic forces, and could be augmented with implementation measures . While Safeguards may be part of a future CTBT debate, both supporters and...A second path involves efforts to alter the net assessment through measures intended to mitigate perceived risks of the treaty. This path has been

High fat diet induced atherosclerosis is accompanied with low colonic bacterial diversity and altered abundances that correlates with plaque size, plasma A-FABP and cholesterol: a pilot study of high fat diet and its intervention with Lactobacillus rhamnosus GG (LGG) or telmisartan in ApoE-/- mice.

PubMed

Chan, Yee Kwan; Brar, Manreetpal Singh; Kirjavainen, Pirkka V; Chen, Yan; Peng, Jiao; Li, Daxu; Leung, Frederick Chi-Ching; El-Nezami, Hani

2016-11-08

Atherosclerosis appears to have multifactorial causes - microbial component like lipopolysaccharides (LPS) and other pathogen associated molecular patterns may be plausible factors. The gut microbiota is an ample source of such stimulants, and its dependent metabolites and altered gut metagenome has been an established link to atherosclerosis. In this exploratory pilot study, we aimed to elucidate whether microbial intervention with probiotics L. rhamnosus GG (LGG) or pharmaceuticals telmisartan (TLM) could improve atherosclerosis in a gut microbiota associated manner. Atherosclerotic phenotype was established by 12 weeks feeding of high fat (HF) diet as opposed to normal chow diet (ND) in apolipoprotein E knockout (ApoE -/- ) mice. LGG or TLM supplementation to HF diet was studied. Both LGG and TLM significantly reduced atherosclerotic plaque size and improved various biomarkers including endotoxin to different extents. Colonial microbiota analysis revealed that TLM restored HF diet induced increase in Firmicutes/Bacteroidetes ratio and decrease in alpha diversity; and led to a more distinct microbial clustering closer to ND in PCoA plot. Eubacteria, Anaeroplasma, Roseburia, Oscillospira and Dehalobacteria appeared to be protective against atherosclerosis and showed significant negative correlation with atherosclerotic plaque size and plasma adipocyte - fatty acid binding protein (A-FABP) and cholesterol. LGG and TLM improved atherosclerosis with TLM having a more distinct alteration in the colonic gut microbiota. Altered bacteria genera and reduced alpha diversity had significant correlations to atherosclerotic plaque size, plasma A-FABP and cholesterol. Future studies on such bacterial functional influence in lipid metabolism will be warranted.

CHAracteristics of research studies that iNfluence practice: a GEneral survey of Canadian orthopaedic Surgeons (CHANGES): a pilot survey.

PubMed

de Sa, Darren; Thornley, Patrick; Evaniew, Nathan; Madden, Kim; Bhandari, Mohit; Ghert, Michelle

2015-01-01

Evidence Based Medicine (EBM) is increasingly being applied to inform clinical decision-making in orthopaedic surgery. Despite the promotion of EBM in Orthopaedic Surgery, the adoption of results from high quality clinical research seems highly unpredictable and does not appear to be driven strictly by randomized trial data. The objective of this study was to pilot a survey to determine if we could identify surgeon opinions on the characteristics of research studies that are perceived as being most likely to influence clinical decision-making among orthopaedic surgeons in Canada. A 28-question electronic survey was distributed to active members of the Canadian Orthopaedic Association (COA) over a period of 11 weeks. The questionnaire sought to analyze the influence of both extrinsic and intrinsic characteristics of research studies and their potential to influence practice patterns. Extrinsic factors included the perceived journal quality and investigator profiles, economic impact, peer/patient/industry influence and individual surgeon residency/fellowship training experiences. Intrinsic factors included study design, sample size, and outcomes reported. Descriptive statistics are provided. Of the 109 members of the COA who opened the survey, 95 (87%) completed the survey in its entirety. The overall response rate was 11% (95/841). Surgeons achieved consensus on the influence of three key designs on their practices: 1) randomized controlled trials 94 (99%), 2) meta-analysis 83 (87%), and 3) systematic reviews 81 (85%). Sixty-seven percent of surgeons agreed that studies with sample sizes of 101-500 or more were more likely to influence clinical practice than smaller studies (n = <100). Factors other than design influencing adoption included 1) reputation of the investigators (99%) and 2) perceived quality of the journal (75%). Although study design and sample size (i.e. minimum of 100 patients) have some influence on clinical decision making, surgeon respondents are equally influenced by investigator reputation and perceived journal quality. At present, continued emphasis on the generation of large, methodologically sound clinical trials remains paramount to translating research findings to clinical practice changes. Specific to this pilot survey, strategies to solicit more widespread responses will be pursued.

Magnetic properties of ZnO nanoparticles.

PubMed

Garcia, M A; Merino, J M; Fernández Pinel, E; Quesada, A; de la Venta, J; Ruíz González, M L; Castro, G R; Crespo, P; Llopis, J; González-Calbet, J M; Hernando, A

2007-06-01

We experimentally show that it is possible to induce room-temperature ferromagnetic-like behavior in ZnO nanoparticles without doping with magnetic impurities but simply inducing an alteration of their electronic configuration. Capping ZnO nanoparticles ( approximately 10 nm size) with different organic molecules produces an alteration of their electronic configuration that depends on the particular molecule, as evidenced by photoluminescence and X-ray absorption spectroscopies and altering their magnetic properties that varies from diamagnetic to ferromagnetic-like behavior.

Relationship between self-discrepancy and worries about penis size in men with body dysmorphic disorder.

PubMed

Veale, David; Miles, Sarah; Read, Julie; Bramley, Sally; Troglia, Andrea; Carmona, Lina; Fiorito, Chiara; Wells, Hannah; Wylie, Kevan; Muir, Gordon

2016-06-01

We explored self-discrepancy in men with body dysmorphic disorder (BDD) concerned about penis size, men without BDD but anxious about penis size, and controls. Men with BDD (n=26) were compared to those with small penis anxiety (SPA; n=31) and controls (n=33), objectively (by measuring) and investigating self-discrepancy: actual size, ideal size, and size they felt they should be according to self and other. Most men under-estimated their penis size, with the BDD group showing the greatest discrepancy between perceived and ideal size. The SPA group showed a larger discrepancy than controls. This was replicated for the perceptions of others, suggesting the BDD group internalised the belief that they should have a larger penis size. There was a significant correlation between symptoms of BDD and this discrepancy. This self-actual and self-ideal/self-should discrepancy and the role of comparing could be targeted in therapy. Copyright © 2016. Published by Elsevier Ltd.

A survey of Australian adult users of altered auditory feedback devices for stuttering: use patterns, perceived effectiveness and satisfaction.

PubMed

Lincoln, Michelle; Walker, Clare

2007-10-15

Small portable devices that provide delayed auditory feedback (DAF) and/or frequency altered feedback (FAF) have been developed and marketed to clinicians and people who stutter as fluency enhancing aids for use in everyday speaking situations. The literature contains many laboratory-based reports about the impact of altered auditory feedback (AAF) on the speech of people who stutter but few reports about its use in everyday speaking situations. This paper investigates use patterns and perceptions of the effectiveness and satisfaction with AAF devices. The current study surveys 14 Australian AAF users. The survey responses revealed varied opinions about AAF devices and their use and effectiveness in everyday speaking situations. Opinions were somewhat related to the type of device used. The results of this study provide some important directions for future research. In particular there is need to investigate the effectiveness of AAF devices when used in conjunction with other traditional treatments.

Economic scarcity alters the perception of race

PubMed Central

Krosch, Amy R.; Amodio, David M.

2014-01-01

When the economy declines, racial minorities are hit the hardest. Although existing explanations for this effect focus on institutional causes, recent psychological findings suggest that scarcity may also alter perceptions of race in ways that exacerbate discrimination. We tested the hypothesis that economic resource scarcity causes decision makers to perceive African Americans as “Blacker” and that this visual distortion elicits disparities in the allocation of resources. Studies 1 and 2 demonstrated that scarcity altered perceptions of race, lowering subjects’ psychophysical threshold for seeing a mixed-race face as “Black” as opposed to “White.” In studies 3 and 4, scarcity led subjects to visualize African American faces as darker and more “stereotypically Black,” compared with a control condition. When presented to naïve subjects, face representations produced under scarcity elicited smaller allocations than control-condition representations. Together, these findings introduce a novel perceptual account for the proliferation of racial disparities under economic scarcity. PMID:24927595

Solar UV light regulates flavonoid metabolism in apple (Malus x domestica).

PubMed

Henry-Kirk, Rebecca A; Plunkett, Blue; Hall, Miriam; McGhie, Tony; Allan, Andrew C; Wargent, Jason J; Espley, Richard V

2018-03-01

Ultraviolet-B light (UV-B) is one environmental signal perceived by plants that affects the flavonoid pathway and influences the levels of anthocyanins, flavonols, and proanthocyanidins. To understand the mechanisms underlying UV exposure, apple trees were grown under spectral filters that altered transmission of solar UV light. Fruit analysis showed that UV induced changes in physiology, metabolism, and gene expression levels during development over a season. These changes were sustained after storage. Under low UV, ripening was delayed, fruit size decreased, and anthocyanin and flavonols were reduced. Expression analysis showed changes in response to UV light levels for genes in the regulation and biosynthesis of anthocyanin and flavonols. Transcription of flavonol synthase (FLS), ELONGATED HYPOCOTYL 5 (HY5), MYB10, and MYB22 were down-regulated throughout fruit development under reduced UV. Functional testing showed that the FLS promoter was activated by HY5, and this response was enhanced by the presence of MYB22. The MYB22 promoter can also be activated by the anthocyanin regulator, MYB10. As ambient levels of UV light vary around the globe, this study has implications for future crop production, the quality of which can be determined by the response to UV. © 2018 John Wiley & Sons Ltd.

Perception of aesthetics and personality traits in orthognathic surgery patients: A comparison of still and moving images

PubMed Central

Tran, Ulrich S.; Wutzl, Arno; Seemann, Rudolf; Millesi, Gabriele; Jagsch, Reinhold

2018-01-01

It is common in practicing orthognathic surgery to evaluate faces with retruded or protruded chins (dysgnathic faces) using photographs. Because motion may alter how the face is perceived, we investigated the perception of faces presented via photographs and videos. Two hundred naïve raters (lay persons, without maxillo facial surgery background) evaluated 12 subjects with varying chin anatomy [so-called skeletal Class I (normal chin), Class II (retruded chin), and Class III (protruded chin)]. Starting from eight traits, with Factor analysis we found a two-Factor solution, i.e. an "aesthetics associated traits cluster" and a Factor "personality traits cluster" which appeared to be uncorrelated. Internal consistency of the Factors found for photographs and videos was excellent. Generally, female raters delivered better ratings than males, but the effect sizes were small. We analyzed differences and the respective effect magnitude between photograph and video perception. For each skeletal class the aesthetics associated dimensions were rated similarly between photographs and video clips. In contrast, specific personality traits were rated differently. Differences in the class-specific personality traits seen on photographs were "smoothed" in the assessment of videos, which implies that photos enhance stereotypes commonly attributed to a retruded or protruded chin. PMID:29775466

Stand-level Allometry in Pinus taeda as Affected by Irrigation and Fertilization

Treesearch

J.S. King; T.J. Albaugh; H.L. Allen; L.W. Kress

1999-01-01

Changing environmental conditions have the potential to alter allometric relationships between plant parts, possibly leading to ecosystem-level feedbacks. We quantified allometric shifts in field-grown loblolly pine (Pinus taeda L.) in response to altered resource availability based on data from multiple harvests to correct for size-related changes...

PROLONGED FLOODING DECREASED STEM DENSITY, TREE SIZE AND SHIFTED COMPOSITION TOWARDS CLONAL SPECIES IN A CENTRAL FLORIDA HARDWOOD SWAMP

EPA Science Inventory

Human modifications of the landscape often cause changes in regional hydrology that, in turn, can result in the alteration of wetland hydrology. Altering hydrology can lead to hydroperiods that have prolonged or insufficient hydration, which can often cause changes in plant comm...

Estimation of wildfire size and risk changes due to fuels treatments

Treesearch

M. A. Cochrane; C. J. Moran; M. C. Wimberly; A. D. Baer; M. A. Finney; K. L. Beckendorf; J. Eidenshink; Z. Zhu

2012-01-01

Human land use practices, altered climates, and shifting forest and fire management policies have increased the frequency of large wildfires several-fold. Mitigation of potential fire behaviour and fire severity have increasingly been attempted through pre-fire alteration of wildland fuels using mechanical treatments and prescribed fires. Despite annual treatment of...

Stimulant Medication and the Hyperactive Adolescent: Myths and Facts.

ERIC Educational Resources Information Center

Clampit, M. K.; Pirkle, Jane B.

1983-01-01

Reviews literature that describes the rational and nonrational factors sustaining the myth that stimulant medication is ineffective for hyperactive adolescents. Discusses methodological problems and factors--such as increasing size, misbehavior and misattribution, and perceived relationship to drug abuse--that influence treatment decisions. (JAC)

Experience affects the outcome of agonistic contests without affecting the selective advantage of size

PubMed Central

Kasumovic, Michael M.; Elias, Damian O.; Punzalan, David; Mason, Andrew C.; Andrade, Maydianne C. B.

2009-01-01

In the field, phenotypic determinants of competitive success are not always absolute. For example, contest experience may alter future competitive performance. As future contests are not determined solely on phenotypic attributes, prior experience could also potentially alter phenotype–fitness associations. In this study, we examined the influence of single and multiple experiences on contest outcomes in the jumping spider Phidippus clarus. We also examined whether phenotype–fitness associations altered as individuals gained more experience. Using both size-matched contests and a tournament design, we found that both winning and losing experience affected future contest success; males with prior winning experience were more likely to win subsequent contests. Although experience was a significant determinant of success in future contests, male weight was approximately 1.3 times more important than experience in predicting contest outcomes. Despite the importance of experience in determining contest outcomes, patterns of selection did not change between rounds. Overall, our results show that experience can be an important determinant in contest outcomes, even in short-lived invertebrates, and that experience alone is unlikely to alter phenotype–fitness associations. PMID:20161296

Experience affects the outcome of agonistic contests without affecting the selective advantage of size.

PubMed

Kasumovic, Michael M; Elias, Damian O; Punzalan, David; Mason, Andrew C; Andrade, Maydianne C B

2009-06-01

In the field, phenotypic determinants of competitive success are not always absolute. For example, contest experience may alter future competitive performance. As future contests are not determined solely on phenotypic attributes, prior experience could also potentially alter phenotype-fitness associations. In this study, we examined the influence of single and multiple experiences on contest outcomes in the jumping spider Phidippus clarus. We also examined whether phenotype-fitness associations altered as individuals gained more experience. Using both size-matched contests and a tournament design, we found that both winning and losing experience affected future contest success; males with prior winning experience were more likely to win subsequent contests. Although experience was a significant determinant of success in future contests, male weight was approximately 1.3 times more important than experience in predicting contest outcomes. Despite the importance of experience in determining contest outcomes, patterns of selection did not change between rounds. Overall, our results show that experience can be an important determinant in contest outcomes, even in short-lived invertebrates, and that experience alone is unlikely to alter phenotype-fitness associations.

Perceived beauty of random texture patterns: A preference for complexity.

PubMed

Friedenberg, Jay; Liby, Bruce

2016-07-01

We report two experiments on the perceived aesthetic quality of random density texture patterns. In each experiment a square grid was filled with a progressively larger number of elements. Grid size in Experiment 1 was 10×10 with elements added to create a variety of textures ranging from 10%-100% fill levels. Participants rated the beauty of the patterns. Average judgments across all observers showed an inverted U-shaped function that peaked near middle densities. In Experiment 2 grid size was increased to 15×15 to see if observers preferred patterns with a fixed density or a fixed number of elements. The results of the second experiment were nearly identical to that of the first showing a preference for density over fixed element number. Ratings in both studies correlated positively with a GIF compression metric of complexity and with edge length. Within the range of stimuli used, observers judge more complex patterns to be more beautiful. Copyright © 2016 Elsevier B.V. All rights reserved.

Meta-Analysis of the Reasoned Action Approach (RAA) to Understanding Health Behaviors.

PubMed

McEachan, Rosemary; Taylor, Natalie; Harrison, Reema; Lawton, Rebecca; Gardner, Peter; Conner, Mark

2016-08-01

Reasoned action approach (RAA) includes subcomponents of attitude (experiential/instrumental), perceived norm (injunctive/descriptive), and perceived behavioral control (capacity/autonomy) to predict intention and behavior. To provide a meta-analysis of the RAA for health behaviors focusing on comparing the pairs of RAA subcomponents and differences between health protection and health-risk behaviors. The present research reports a meta-analysis of correlational tests of RAA subcomponents, examination of moderators, and combined effects of subcomponents on intention and behavior. Regressions were used to predict intention and behavior based on data from studies measuring all variables. Capacity and experiential attitude had large, and other constructs had small-medium-sized correlations with intention; all constructs except autonomy were significant independent predictors of intention in regressions. Intention, capacity, and experiential attitude had medium-large, and other constructs had small-medium-sized correlations with behavior; intention, capacity, experiential attitude, and descriptive norm were significant independent predictors of behavior in regressions. The RAA subcomponents have utility in predicting and understanding health behaviors.

The malleability of gender stereotypes: influence of population size on perceptions of men and women in the past, present, and future.

PubMed

Garcia-Retamero, Rocio; Müller, Stephanie M; López-Zafra, Esther

2011-01-01

Recent studies on the malleability of gender stereotypes show that they are flexible, dynamic structures that change with the passage of time. In a study, we examined perceptions about men and women of the past, present, and future in Spain and focused on the influence of an important demographic variable on these perceptions: the population size of people's location of residence. Results showed that people perceived an increase in similarity of men and women from the past to the present and from the present to the future. In less-populated locations, however, men and women were more gender stereotyped and, consequently, still perceived to be further from equality than those in more populated areas. We concluded that the study of dynamic gender stereotypes benefits from extensive research in populations that vary in their demographic characteristics and shows the importance of recent movements in rural areas supporting women's participation in the modernization process.

Predicting bias in perceived position using attention field models.

PubMed

Klein, Barrie P; Paffen, Chris L E; Pas, Susan F Te; Dumoulin, Serge O

2016-05-01

Attention is the mechanism through which we select relevant information from our visual environment. We have recently demonstrated that attention attracts receptive fields across the visual hierarchy (Klein, Harvey, & Dumoulin, 2014). We captured this receptive field attraction using an attention field model. Here, we apply this model to human perception: We predict that receptive field attraction results in a bias in perceived position, which depends on the size of the underlying receptive fields. We instructed participants to compare the relative position of Gabor stimuli, while we manipulated the focus of attention using exogenous cueing. We varied the eccentric position and spatial frequency of the Gabor stimuli to vary underlying receptive field size. The positional biases as a function of eccentricity matched the predictions by an attention field model, whereas the bias as a function of spatial frequency did not. As spatial frequency and eccentricity are encoded differently across the visual hierarchy, we speculate that they might interact differently with the attention field that is spatially defined.

Environmental factors and puberty timing: Expert panel research needs

EPA Science Inventory

An expert panel reviewed the literature on endocrine disrupting chemicals (EDCs), body size and puberty. The panel concluded that available experimental animal and human data support a possible role of EDCs and body size in relation to alterations in pubertal onset and progressio...

Alterations in welding process voltage affect the generation of ultrafine particles, fume composition, and pulmonary toxicity.

PubMed

Antonini, James M; Keane, Michael; Chen, Bean T; Stone, Samuel; Roberts, Jenny R; Schwegler-Berry, Diane; Andrews, Ronnee N; Frazer, David G; Sriram, Krishnan

2011-12-01

The goal was to determine if increasing welding voltage changes the physico-chemical properties of the fume and influences lung responses. Rats inhaled 40 mg/m³ (3 h/day × 3 days) of stainless steel (SS) welding fume generated at a standard voltage setting of 25 V (regular SS) or at a higher voltage (high voltage SS) of 30 V. Particle morphology, size and composition were characterized. Bronchoalveolar lavage was performed at different times after exposures to assess lung injury. Fumes collected from either of the welding conditions appeared as chain-like agglomerates of nanometer-sized primary particles. High voltage SS welding produced a greater number of ultrafine-sized particles. Fume generated by high voltage SS welding was higher in manganese. Pulmonary toxicity was more substantial and persisted longer after exposure to the regular SS fume. In summary, a modest raise in welding voltage affected fume size and elemental composition and altered the temporal lung toxicity profile.

Tunable particles alter macrophage uptake based on combinatorial effects of physical properties

PubMed Central

Garapaty, Anusha

2017-01-01

Abstract The ability to tune phagocytosis of particle‐based therapeutics by macrophages can enhance their delivery to macrophages or reduce their phagocytic susceptibility for delivery to non‐phagocytic cells. Since phagocytosis is affected by the physical and chemical properties of particles, it is crucial to identify any interplay between physical properties of particles in altering phagocytic interactions. The combinatorial effect of physical properties size, shape and stiffness was investigated on Fc receptor mediated macrophage interactions by fabrication of layer‐by‐layer tunable particles of constant surface chemistry. Our results highlight how changing particle stiffness affects phagocytic interaction intricately when combined with varying size or shape. Increase in size plays a dominant role over reduction in stiffness in reducing internalization by macrophages for spherical particles. Internalization of rod‐shaped, but not spherical particles, was highly dependent on stiffness. These particles demonstrate the interplay between size, shape and stiffness in interactions of Fc‐functionalized particles with macrophages during phagocytosis. PMID:29313025

Influence of riparian and watershed alterations on sandbars in a Great Plains river

USGS Publications Warehouse

Fischer, Jeffrey M.; Paukert, Craig P.; Daniels, M.L.

2014-01-01

Anthropogenic alterations have caused sandbar habitats in rivers and the biota dependent on them to decline. Restoring large river sandbars may be needed as these habitats are important components of river ecosystems and provide essential habitat to terrestrial and aquatic organisms. We quantified factors within the riparian zone of the Kansas River, USA, and within its tributaries that influenced sandbar size and density using aerial photographs and land use/land cover (LULC) data. We developed, a priori, 16 linear regression models focused on LULC at the local, adjacent upstream river bend, and the segment (18–44 km upstream) scales and used an information theoretic approach to determine what alterations best predicted the size and density of sandbars. Variation in sandbar density was best explained by the LULC within contributing tributaries at the segment scale, which indicated reduced sandbar density with increased forest cover within tributary watersheds. Similarly, LULC within contributing tributary watersheds at the segment scale best explained variation in sandbar size. These models indicated that sandbar size increased with agriculture and forest and decreased with urban cover within tributary watersheds. Our findings suggest that sediment supply and delivery from upstream tributary watersheds may be influential on sandbars within the Kansas River and that preserving natural grassland and reducing woody encroachment within tributary watersheds in Great Plains rivers may help improve sediment delivery to help restore natural river function.