The Effects of Face Inversion and Face Race on the P100 ERP.
Colombatto, Clara; McCarthy, Gregory
2017-04-01
Research about the neural basis of face recognition has investigated the timing and anatomical substrates of different stages of face processing. Scalp-recorded ERP studies of face processing have focused on the N170, an ERP with a peak latency of ∼170 msec that has long been associated with the initial structural encoding of faces. However, several studies have reported earlier ERP differences related to faces, suggesting that face-specific processes might occur before N170. Here, we examined the influence of face inversion and face race on the timing of face-sensitive scalp-recorded ERPs by examining neural responses to upright and inverted line-drawn and luminance-matched white and black faces in a sample of white participants. We found that the P100 ERP evoked by inverted faces was significantly larger than that evoked by upright faces. Although this inversion effect was statistically significant at 100 msec, the inverted-upright ERP difference peaked at 138 msec, suggesting that it might represent an activity in neural sources that overlap with P100. Inverse modeling of the inversion effect difference waveform suggested possible neural sources in pericalcarine extrastriate visual cortex and lateral occipito-temporal cortex. We also found that the inversion effect difference wave was larger for white faces. These results are consistent with behavioral evidence that individuals process the faces of their own races more configurally than faces of other races. Taken together, the inversion and race effects observed in the current study suggest that configuration influences face processing by at least 100 msec.
Komes, Jessica; Schweinberger, Stefan R.; Wiese, Holger
2015-01-01
Previous event-related potential (ERP) research revealed that older relative to younger adults show reduced inversion effects in the N170 (with more negative amplitudes for inverted than upright faces), suggestive of impairments in face perception. However, as these studies used young to middle-aged faces only, this finding may reflect preferential processing of own- relative to other-age faces rather than age-related decline. We conducted an ERP study in which young and older participants categorized young and old upright or inverted faces by age. Stimuli were presented either unfiltered or low-pass filtered at 30, 20, or 10 cycles per image (CPI). Response times revealed larger inversion effects, with slower responses for inverted faces, for young faces in young participants. Older participants did not show a corresponding effect. ERPs yielded a trend toward reduced N170 inversion effects in older relative to younger adults independent of face age. Moreover, larger inversion effects for young relative to old faces were detected, and filtering resulted in smaller N170 amplitudes. The reduced N170 inversion effect in older adults may reflect age-related changes in neural correlates of face perception. A smaller N170 inversion effect for old faces may indicate that facial changes with age hamper early face perception stages. PMID:26441790
Attention Misplaced: The Role of Diagnostic Features in the Face-Inversion Effect
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Hills, Peter J.; Ross, David A.; Lewis, Michael B.
2011-01-01
Inversion disproportionately impairs recognition of face stimuli compared to nonface stimuli arguably due to the holistic manner in which faces are processed. A qualification is put forward in which the first point fixated on is different for upright and inverted faces and this carries some of the face-inversion effect. Three experiments explored…
Face-Evoked Steady-State Visual Potentials: Effects of Presentation Rate and Face Inversion
Gruss, L. Forest; Wieser, Matthias J.; Schweinberger, Stefan R.; Keil, Andreas
2012-01-01
Face processing can be explored using electrophysiological methods. Research with event-related potentials has demonstrated the so-called face inversion effect, in which the N170 component is enhanced in amplitude and latency to inverted, compared to upright, faces. The present study explored the extent to which repetitive lower-level visual cortical engagement, reflected in flicker steady-state visual evoked potentials (ssVEPs), shows similar amplitude enhancement to face inversion. We also asked if inversion-related ssVEP modulation would be dependent on the stimulation rate at which upright and inverted faces were flickered. To this end, multiple tagging frequencies were used (5, 10, 15, and 20 Hz) across two studies (n = 21, n = 18). Results showed that amplitude enhancement of the ssVEP for inverted faces was found solely at higher stimulation frequencies (15 and 20 Hz). By contrast, lower frequency ssVEPs did not show this inversion effect. These findings suggest that stimulation frequency affects the sensitivity of ssVEPs to face inversion. PMID:23205009
The Effect of Inversion on 3- to 5-Year-Olds' Recognition of Face and Nonface Visual Objects
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Picozzi, Marta; Cassia, Viola Macchi; Turati, Chiara; Vescovo, Elena
2009-01-01
This study compared the effect of stimulus inversion on 3- to 5-year-olds' recognition of faces and two nonface object categories matched with faces for a number of attributes: shoes (Experiment 1) and frontal images of cars (Experiments 2 and 3). The inversion effect was present for faces but not shoes at 3 years of age (Experiment 1). Analogous…
The role of experience-based perceptual learning in the face inversion effect.
Civile, Ciro; Obhi, Sukhvinder S; McLaren, I P L
2018-04-03
Perceptual learning of the type we consider here is a consequence of experience with a class of stimuli. It amounts to an enhanced ability to discriminate between stimuli. We argue that it contributes to the ability to distinguish between faces and recognize individuals, and in particular contributes to the face inversion effect (better recognition performance for upright vs inverted faces). Previously, we have shown that experience with a prototype defined category of checkerboards leads to perceptual learning, that this produces an inversion effect, and that this effect can be disrupted by Anodal tDCS to Fp3 during pre-exposure. If we can demonstrate that the same tDCS manipulation also disrupts the inversion effect for faces, then this will strengthen the claim that perceptual learning contributes to that effect. The important question, then, is whether this tDCS procedure would significantly reduce the inversion effect for faces; stimuli that we have lifelong expertise with and for which perceptual learning has already occurred. Consequently, in the experiment reported here we investigated the effects of anodal tDCS at Fp3 during an old/new recognition task for upright and inverted faces. Our results show that stimulation significantly reduced the face inversion effect compared to controls. The effect was one of reducing recognition performance for upright faces. This result is the first to show that tDCS affects perceptual learning that has already occurred, disrupting individuals' ability to recognize upright faces. It provides further support for our account of perceptual learning and its role as a key factor in face recognition. Copyright © 2018 Elsevier Ltd. All rights reserved.
Developmental origins of the face inversion effect.
Cashon, Cara H; Holt, Nicholas A
2015-01-01
A hallmark of adults' expertise for faces is that they are better at recognizing, discriminating, and processing upright faces compared to inverted faces. We investigate the developmental origins of "the face inversion effect" by reviewing research on infants' perception of upright and inverted faces during the first year of life. We review the effects of inversion on infants' face preference, recognition, processing (holistic and second-order configural), and scanning as well as face-related neural responses. Particular attention is paid to the developmental patterns that emerge within and across these areas of face perception. We conclude that the developmental origins of the inversion effect begin in the first few months of life and grow stronger over the first year, culminating in effects that are commonly thought to indicate adult-like expertise. We posit that by the end of the first year, infants' face-processing system has become specialized to upright faces and a foundation for adults' upright-face expertise has been established. Developmental mechanisms that may facilitate the emergence of this upright-face specialization are discussed, including the roles that physical and social development may play in upright faces' becoming more meaningful to infants during the first year. © 2015 Elsevier Inc. All rights reserved.
Bonemei, Rob; Costantino, Andrea I; Battistel, Ilenia; Rivolta, Davide
2018-05-01
Faces and bodies are more difficult to perceive when presented inverted than when presented upright (i.e., stimulus inversion effect), an effect that has been attributed to the disruption of holistic processing. The features that can trigger holistic processing in faces and bodies, however, still remain elusive. In this study, using a sequential matching task, we tested whether stimulus inversion affects various categories of visual stimuli: faces, faceless heads, faceless heads in body context, headless bodies naked, whole bodies naked, headless bodies clothed, and whole bodies clothed. Both accuracy and inversion efficiency score results show inversion effects for all categories but for clothed bodies (with and without heads). In addition, the magnitude of the inversion effect for face, naked body, and faceless heads was similar. Our findings demonstrate that the perception of faces, faceless heads, and naked bodies relies on holistic processing. Clothed bodies (with and without heads), on the other side, may trigger clothes-sensitive rather than body-sensitive perceptual mechanisms. © 2017 The British Psychological Society.
A Face Inversion Effect without a Face
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Brandman, Talia; Yovel, Galit
2012-01-01
Numerous studies have attributed the face inversion effect (FIE) to configural processing of internal facial features in upright but not inverted faces. Recent findings suggest that face mechanisms can be activated by faceless stimuli presented in the context of a body. Here we asked whether faceless stimuli with or without body context may induce…
Familiarity facilitates feature-based face processing.
Visconti di Oleggio Castello, Matteo; Wheeler, Kelsey G; Cipolli, Carlo; Gobbini, M Ida
2017-01-01
Recognition of personally familiar faces is remarkably efficient, effortless and robust. We asked if feature-based face processing facilitates detection of familiar faces by testing the effect of face inversion on a visual search task for familiar and unfamiliar faces. Because face inversion disrupts configural and holistic face processing, we hypothesized that inversion would diminish the familiarity advantage to the extent that it is mediated by such processing. Subjects detected personally familiar and stranger target faces in arrays of two, four, or six face images. Subjects showed significant facilitation of personally familiar face detection for both upright and inverted faces. The effect of familiarity on target absent trials, which involved only rejection of unfamiliar face distractors, suggests that familiarity facilitates rejection of unfamiliar distractors as well as detection of familiar targets. The preserved familiarity effect for inverted faces suggests that facilitation of face detection afforded by familiarity reflects mostly feature-based processes.
Super-recognizers: people with extraordinary face recognition ability.
Russell, Richard; Duchaine, Brad; Nakayama, Ken
2009-04-01
We tested 4 people who claimed to have significantly better than ordinary face recognition ability. Exceptional ability was confirmed in each case. On two very different tests of face recognition, all 4 experimental subjects performed beyond the range of control subject performance. They also scored significantly better than average on a perceptual discrimination test with faces. This effect was larger with upright than with inverted faces, and the 4 subjects showed a larger "inversion effect" than did control subjects, who in turn showed a larger inversion effect than did developmental prosopagnosics. This result indicates an association between face recognition ability and the magnitude of the inversion effect. Overall, these "super-recognizers" are about as good at face recognition and perception as developmental prosopagnosics are bad. Our findings demonstrate the existence of people with exceptionally good face recognition ability and show that the range of face recognition and face perception ability is wider than has been previously acknowledged.
Meinhardt, Günter; Kurbel, David; Meinhardt-Injac, Bozana; Persike, Malte
2018-03-22
Some years ago an asymmetry was reported for the inversion effect for horizontal (H) and vertical (V) relational face manipulations (Goffaux & Rossion, 2007). Subsequent research examined whether a specific disruption of long-range relations underlies the H/V inversion asymmetry (Sekunova & Barton, 2008). Here, we tested how detection of changes in interocular distance (H) and eye height (V) depends on cardinal internal features and external feature surround. Results replicated the H/V inversion asymmetry. Moreover, we found very different face cue dependencies for both change types. Performance and inversion effects did not depend on the presence of other face cues for detecting H changes. In contrast, accuracy for detecting V changes strongly depended on internal and external features, showing cumulative improvement when more cues were added. Inversion effects were generally large, and larger with external feature surround. The cue independence in detecting H relational changes indicates specialized local processing tightly tuned to the eyes region, while the strong cue dependency in detecting V relational changes indicates a global mechanism of cue integration across different face regions. These findings suggest that the H/V asymmetry of the inversion effect rests on an H/V anisotropy of face cue dependency, since only the global V mechanism suffers from disruption of cue integration as the major effect of face inversion. Copyright © 2018. Published by Elsevier Ltd.
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Bedard, Catherine; Belin, Pascal
2004-01-01
Voice is the carrier of speech but is also an ''auditory face'' rich in information on the speaker's identity and affective state. Three experiments explored the possibility of a ''voice inversion effect,'' by analogy to the classical ''face inversion effect,'' which could support the hypothesis of a voice-specific module. Experiment 1 consisted…
Sugase-Miyamoto, Yasuko; Matsumoto, Narihisa; Ohyama, Kaoru; Kawano, Kenji
2014-09-10
To investigate the effect of face inversion and thatcherization (eye inversion) on temporal processing stages of facial information, single neuron activities in the temporal cortex (area TE) of two rhesus monkeys were recorded. Test stimuli were colored pictures of monkey faces (four with four different expressions), human faces (three with four different expressions), and geometric shapes. Modifications were made in each face-picture, and its four variations were used as stimuli: upright original, inverted original, upright thatcherized, and inverted thatcherized faces. A total of 119 neurons responded to at least one of the upright original facial stimuli. A majority of the neurons (71%) showed activity modulations depending on upright and inverted presentations, and a lesser number of neurons (13%) showed activity modulations depending on original and thatcherized face conditions. In the case of face inversion, information about the fine category (facial identity and expression) decreased, whereas information about the global category (monkey vs human vs shape) was retained for both the original and thatcherized faces. Principal component analysis on the neuronal population responses revealed that the global categorization occurred regardless of the face inversion and that the inverted faces were represented near the upright faces in the principal component analysis space. By contrast, the face inversion decreased the ability to represent human facial identity and monkey facial expression. Thus, the neuronal population represented inverted faces as faces but failed to represent the identity and expression of the inverted faces, indicating that the neuronal representation in area TE cause the perceptual effect of face inversion. Copyright © 2014 the authors 0270-6474/14/3412457-13$15.00/0.
Lavallée, Marie Maxime; Gandini, Delphine; Rouleau, Isabelle; Vallet, Guillaume T; Joannette, Maude; Kergoat, Marie-Jeanne; Busigny, Thomas; Rossion, Bruno; Joubert, Sven
2016-01-01
Prevalent face recognition difficulties in Alzheimer's disease (AD) have typically been attributed to the underlying episodic and semantic memory impairment. The aim of the current study was to determine if AD patients are also impaired at the perceptual level for faces, more specifically at extracting a visual representation of an individual face. To address this question, we investigated the matching of simultaneously presented individual faces and of other nonface familiar shapes (cars), at both upright and inverted orientation, in a group of mild AD patients and in a group of healthy older controls matched for age and education. AD patients showed a reduced inversion effect (i.e., larger performance for upright than inverted stimuli) for faces, but not for cars, both in terms of error rates and response times. While healthy participants showed a much larger decrease in performance for faces than for cars with inversion, the inversion effect did not differ significantly for faces and cars in AD. This abnormal inversion effect for faces was observed in a large subset of individual patients with AD. These results suggest that AD patients have deficits in higher-level visual processes, more specifically at perceiving individual faces, a function that relies on holistic representations specific to upright face stimuli. These deficits, combined with their memory impairment, may contribute to the difficulties in recognizing familiar people that are often reported in patients suffering from the disease and by their caregivers.
Chinese Characters Elicit Face-Like N170 Inversion Effects
ERIC Educational Resources Information Center
Wang, Man-Ying; Kuo, Bo-Cheng; Cheng, Shih-Kuen
2011-01-01
Recognition of both faces and Chinese characters is commonly believed to rely on configural information. While faces typically exhibit behavioral and N170 inversion effects that differ from non-face stimuli (Rossion, Joyce, Cottrell, & Tarr, 2003), the current study examined whether a similar reliance on configural processing may result in similar…
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Sangrigoli, Sandy; de Schonen, Scania
2004-01-01
In adults, three phenomena are taken to demonstrate an experience effect on face recognition: an inversion effect, a non-native face effect (so-called "other-race" effect) and their interaction. It is crucial for our understanding of the developmental perception mechanisms of object processing to discover when these effects are present in…
Yovel, Galit
2009-11-01
It is often argued that picture-plane face inversion impairs discrimination of the spacing among face features to a greater extent than the identity of the facial features. However, several recent studies have reported similar inversion effects for both types of face manipulations. In a recent review, Rossion (2008) claimed that similar inversion effects for spacing and features are due to methodological and conceptual shortcomings and that data still support the idea that inversion impairs the discrimination of features less than that of the spacing among them. Here I will claim that when facial features differ primarily in shape, the effect of inversion on features is not smaller than the one on spacing. It is when color/contrast information is added to facial features that the inversion effect on features decreases. This obvious observation accounts for the discrepancy in the literature and suggests that the large inversion effect that was found for features that differ in shape is not a methodological artifact. These findings together with other data that are discussed are consistent with the idea that the shape of facial features and the spacing among them are integrated rather than dissociated in the holistic representation of faces.
Super-recognizers: People with extraordinary face recognition ability
Russell, Richard; Duchaine, Brad; Nakayama, Ken
2014-01-01
We tested four people who claimed to have significantly better than ordinary face recognition ability. Exceptional ability was confirmed in each case. On two very different tests of face recognition, all four experimental subjects performed beyond the range of control subject performance. They also scored significantly better than average on a perceptual discrimination test with faces. This effect was larger with upright than inverted faces, and the four subjects showed a larger ‘inversion effect’ than control subjects, who in turn showed a larger inversion effect than developmental prosopagnosics. This indicates an association between face recognition ability and the magnitude of the inversion effect. Overall, these ‘super-recognizers’ are about as good at face recognition and perception as developmental prosopagnosics are bad. Our findings demonstrate the existence of people with exceptionally good face recognition ability, and show that the range of face recognition and face perception ability is wider than previously acknowledged. PMID:19293090
Combined Effects of Inversion and Feature Removal on N170 Responses Elicited by Faces and Car Fronts
ERIC Educational Resources Information Center
Kloth, Nadine; Itier, Roxane J.; Schweinberger, Stefan R.
2013-01-01
The face-sensitive N170 is typically enhanced for inverted compared to upright faces. Itier, Alain, Sedore, and McIntosh (2007) recently suggested that this N170 inversion effect is mainly driven by the eye region which becomes salient when the face configuration is disrupted. Here we tested whether similar effects could be observed with non-face…
Kret, Mariska E; Tomonaga, Masaki
2016-01-01
For social species such as primates, the recognition of conspecifics is crucial for their survival. As demonstrated by the 'face inversion effect', humans are experts in recognizing faces and unlike objects, recognize their identity by processing it configurally. The human face, with its distinct features such as eye-whites, eyebrows, red lips and cheeks signals emotions, intentions, health and sexual attraction and, as we will show here, shares important features with the primate behind. Chimpanzee females show a swelling and reddening of the anogenital region around the time of ovulation. This provides an important socio-sexual signal for group members, who can identify individuals by their behinds. We hypothesized that chimpanzees process behinds configurally in a way humans process faces. In four different delayed matching-to-sample tasks with upright and inverted body parts, we show that humans demonstrate a face, but not a behind inversion effect and that chimpanzees show a behind, but no clear face inversion effect. The findings suggest an evolutionary shift in socio-sexual signalling function from behinds to faces, two hairless, symmetrical and attractive body parts, which might have attuned the human brain to process faces, and the human face to become more behind-like.
The effect of inversion on face recognition in adults with autism spectrum disorder.
Hedley, Darren; Brewer, Neil; Young, Robyn
2015-05-01
Face identity recognition has widely been shown to be impaired in individuals with autism spectrum disorders (ASD). In this study we examined the influence of inversion on face recognition in 26 adults with ASD and 33 age and IQ matched controls. Participants completed a recognition test comprising upright and inverted faces. Participants with ASD performed worse than controls on the recognition task but did not show an advantage for inverted face recognition. Both groups directed more visual attention to the eye than the mouth region and gaze patterns were not found to be associated with recognition performance. These results provide evidence of a normal effect of inversion on face recognition in adults with ASD.
The Effect of Inversion on Face Recognition in Adults with Autism Spectrum Disorder
ERIC Educational Resources Information Center
Hedley, Darren; Brewer, Neil; Young, Robyn
2015-01-01
Face identity recognition has widely been shown to be impaired in individuals with autism spectrum disorders (ASD). In this study we examined the influence of inversion on face recognition in 26 adults with ASD and 33 age and IQ matched controls. Participants completed a recognition test comprising upright and inverted faces. Participants with ASD…
ERIC Educational Resources Information Center
Reed, Catherine L.; Beall, Paula M.; Stone, Valerie E.; Kopelioff, Lila; Pulham, Danielle J.; Hepburn, Susan L.
2007-01-01
Autism has been associated with atypical face and configural processing, as indicated by the lack of a face inversion effect (better recognition of upright than inverted faces). We investigated whether such atypical processing was restricted to the face or extended to social information found in body postures. An inversion paradigm compared…
Faces in Context: Does Face Perception Depend on the Orientation of the Visual Scene?
Taubert, Jessica; van Golde, Celine; Verstraten, Frans A J
2016-10-01
The mechanisms held responsible for familiar face recognition are thought to be orientation dependent; inverted faces are more difficult to recognize than their upright counterparts. Although this effect of inversion has been investigated extensively, researchers have typically sliced faces from photographs and presented them in isolation. As such, it is not known whether the perceived orientation of a face is inherited from the visual scene in which it appears. Here, we address this question by measuring performance in a simultaneous same-different task while manipulating both the orientation of the faces and the scene. We found that the face inversion effect survived scene inversion. Nonetheless, an improvement in performance when the scene was upside down suggests that sensitivity to identity increased when the faces were more easily segmented from the scene. Thus, while these data identify congruency with the visual environment as a contributing factor in recognition performance, they imply different mechanisms operate on upright and inverted faces. © The Author(s) 2016.
Face inversion effects in autism: a combined looking time and pupillometric study.
Falck-Ytter, Terje
2008-10-01
Previous research has found that in typically developing individuals, behavioral performance declines and electrophysiological brain responses are altered when the face is inverted. Such effects are generally attributed to disruption of configural information. Individuals with autism spectrum disorder (ASD) have been found to show less pronounced inversion effects, a result in line with the view that featural processing of faces is enhanced in ASD. No study has determined if, or how, such local bias is reflected in the eye movements used in face observation. In this eye tracking study, looking time and pupil dilation were investigated during the presentation of upright and inverted faces in preschool children with ASD and typically developing preschoolers. On average, both children with ASD and typically developing children looked less at the face and the eye areas during inverted presentations than during upright presentations. Nevertheless, individuals with ASD had a stronger tendency than typically developing children to look at the same face features during upright and inverted presentations, which is suggestive of a local bias. Pupil dilation, reflecting increased processing load, was larger for inverted than upright faces in the ASD group only, and pupillary inversion effects were stronger in ASD than in typically developing children.
Tanaka, James W; Kaiser, Martha D; Hagen, Simen; Pierce, Lara J
2014-05-01
Given that all faces share the same set of features-two eyes, a nose, and a mouth-that are arranged in similar configuration, recognition of a specific face must depend on our ability to discern subtle differences in its featural and configural properties. An enduring question in the face-processing literature is whether featural or configural information plays a larger role in the recognition process. To address this question, the face dimensions task was designed, in which the featural and configural properties in the upper (eye) and lower (mouth) regions of a face were parametrically and independently manipulated. In a same-different task, two faces were sequentially presented and tested in their upright or in their inverted orientation. Inversion disrupted the perception of featural size (Exp. 1), featural shape (Exp. 2), and configural changes in the mouth region, but it had relatively little effect on the discrimination of featural size and shape and configural differences in the eye region. Inversion had little effect on the perception of information in the top and bottom halves of houses (Exp. 3), suggesting that the lower-half impairment was specific to faces. Spatial cueing to the mouth region eliminated the inversion effect (Exp. 4), suggesting that participants have a bias to attend to the eye region of an inverted face. The collective findings from these experiments suggest that inversion does not differentially impair featural or configural face perceptions, but rather impairs the perception of information in the mouth region of the face.
Lahaie, A; Mottron, L; Arguin, M; Berthiaume, C; Jemel, B; Saumier, D
2006-01-01
Configural processing in autism was studied in Experiment 1 by using the face inversion effect. A normal inversion effect was observed in the participants with autism, suggesting intact configural face processing. A priming paradigm using partial or complete faces served in Experiment 2 to assess both local and configural face processing. Overall, normal priming effects were found in participants with autism, irrespective of whether the partial face primes were intuitive face parts (i.e., eyes, nose, etc.) or arbitrary segments. An exception, however, was that participants with autism showed magnified priming with single face parts relative to typically developing control participants. The present findings argue for intact configural processing in autism along with an enhanced processing for individual face parts. The face-processing peculiarities known to characterize autism are discussed on the basis of these results and past congruent results with nonsocial stimuli.
Itier, Roxane J; Taylor, Margot J
2002-02-01
Using ERPs in a face recognition task, we investigated whether inversion and contrast reversal, which seem to disrupt different aspects of face configuration, differentially affected encoding and memory for faces. Upright, inverted, and negative (contrast-reversed) unknown faces were either immediately repeated (0-lag) or repeated after 1 intervening face (1-lag). The encoding condition (new) consisted of the first presentation of items correctly recognized in the two repeated conditions. 0-lag faces were recognized better and faster than 1-lag faces. Inverted and negative pictures elicited longer reaction times, lower hit rates, and higher false alarm rates than upright faces. ERP analyses revealed that negative and inverted faces affected both early (encoding) and late (recognition) stages of face processing. Early components (N170, VPP) were delayed and enhanced by both inversion and contrast reversal which also affected P1 and P2 components. Amplitudes were higher for inverted faces at frontal and parietal sites from 350 to 600 ms. Priming effects were seen at encoding stages, revealed by shorter latencies and smaller amplitudes of N170 for repeated stimuli, which did not differ depending on face type. Repeated faces yielded more positive amplitudes than new faces from 250 to 450 ms frontally and from 400 to 600 ms parietally. However, ERP differences revealed that the magnitude of this repetition effect was smaller for negative and inverted than upright faces at 0-lag but not at 1-lag condition. Thus, face encoding and recognition processes were affected by inversion and contrast-reversal differently.
Effects of configural processing on the perceptual spatial resolution for face features.
Namdar, Gal; Avidan, Galia; Ganel, Tzvi
2015-11-01
Configural processing governs human perception across various domains, including face perception. An established marker of configural face perception is the face inversion effect, in which performance is typically better for upright compared to inverted faces. In two experiments, we tested whether configural processing could influence basic visual abilities such as perceptual spatial resolution (i.e., the ability to detect spatial visual changes). Face-related perceptual spatial resolution was assessed by measuring the just noticeable difference (JND) to subtle positional changes between specific features in upright and inverted faces. The results revealed robust inversion effect for spatial sensitivity to configural-based changes, such as the distance between the mouth and the nose, or the distance between the eyes and the nose. Critically, spatial resolution for face features within the region of the eyes (e.g., the interocular distance between the eyes) was not affected by inversion, suggesting that the eye region operates as a separate 'gestalt' unit which is relatively immune to manipulations that would normally hamper configural processing. Together these findings suggest that face orientation modulates fundamental psychophysical abilities including spatial resolution. Furthermore, they indicate that classic psychophysical methods can be used as a valid measure of configural face processing. Copyright © 2015 Elsevier Ltd. All rights reserved.
Individual Differences in (Non-Visual) Processing Style Predict the Face Inversion Effect
ERIC Educational Resources Information Center
Wyer, Natalie A.; Martin, Douglas; Pickup, Tracey; Macrae, C. Neil
2012-01-01
Recent research suggests that individuals with relatively weak global precedence (i.e., a smaller propensity to view visual stimuli in a configural manner) show a reduced face inversion effect (FIE). Coupled with such findings, a number of recent studies have demonstrated links between an advantage for feature-based processing and the presentation…
Face and body perception in schizophrenia: a configural processing deficit?
Soria Bauser, Denise; Thoma, Patrizia; Aizenberg, Victoria; Brüne, Martin; Juckel, Georg; Daum, Irene
2012-01-30
Face and body perception rely on common processing mechanisms and activate similar but not identical brain networks. Patients with schizophrenia show impaired face perception, and the present study addressed for the first time body perception in this group. Seventeen patients diagnosed with schizophrenia or schizoaffective disorder were compared to 17 healthy controls on standardized tests assessing basic face perception skills (identity discrimination, memory for faces, recognition of facial affect). A matching-to-sample task including emotional and neutral faces, bodies and cars either in an upright or in an inverted position was administered to assess potential category-specific performance deficits and impairments of configural processing. Relative to healthy controls, schizophrenia patients showed poorer performance on the tasks assessing face perception skills. In the matching-to-sample task, they also responded more slowly and less accurately than controls, regardless of the stimulus category. Accuracy analysis showed significant inversion effects for faces and bodies across groups, reflecting configural processing mechanisms; however reaction time analysis indicated evidence of reduced inversion effects regardless of category in schizophrenia patients. The magnitude of the inversion effects was not related to clinical symptoms. Overall, the data point towards reduced configural processing, not only for faces but also for bodies and cars in individuals with schizophrenia. © 2011 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Sekunova, Alla; Barton, Jason J. S.
2008-01-01
A recent study hypothesized a configurational anisotropy in the face inversion effect, with vertical relations more difficult to process. However, another difference in the stimuli of that report was that the vertical but not horizontal shifts lacked local spatial references. Difficulty processing long-range spatial relations might also be…
Munk, Aisha J. L.; Hermann, Andrea; El Shazly, Jasmin; Grant, Phillip; Hennig, Jürgen
2016-01-01
Background In event-related potentials, the N170 manifests itself especially in reaction to faces. In the healthy population, face-inversion leads to stronger negative amplitudes and prolonged latencies of the N170, effects not being present in patients with autism-spectrum-disorder (ASD). ASD has frequently been associated with differences in oxytocinergic neurotransmission. This ERP-study aimed to investigate the face-inversion effect in association with oxytocinergic candidate genes. It was expected that risk-allele-carriers of the oxytocin-receptor-gene-polymorphism (rs53576) and of CD38 (rs379863) responded similar to upright and inverted faces as persons with ASD. Additionally, reactions to different facial emotional expressions were studied. As there have been difficulties with replications of those molecular genetic association studies, we aimed to replicate our findings in a second study. Method Seventy-two male subjects in the first-, and seventy-eight young male subjects in the replication-study conducted a face-inversion-paradigm, while recording EEG. DNA was extracted from buccal cells. Results Results revealed stronger N170-amplitudes and longer latencies in reaction to inverted faces in comparison to upright ones. Furthermore, effects of emotion on N170 were evident. Those effects were present in the first and in the second study. Whereas we found molecular-genetic associations of oxytocinergic polymorphisms with the N170 in the first study, we failed to do so in the replication sample. Conclusion Results indicate that a deeper theoretical understanding of this research-field is needed, in order to generate possible explanations for these findings. Results, furthermore, support the hypotheses that success of reproducibility is correlated with strength of lower original p-values and larger effect sizes in the original study. PMID:27015428
Orientation-sensitivity to facial features explains the Thatcher illusion.
Psalta, Lilia; Young, Andrew W; Thompson, Peter; Andrews, Timothy J
2014-10-09
The Thatcher illusion provides a compelling example of the perceptual cost of face inversion. The Thatcher illusion is often thought to result from a disruption to the processing of spatial relations between face features. Here, we show the limitations of this account and instead demonstrate that the effect of inversion in the Thatcher illusion is better explained by a disruption to the processing of purely local facial features. Using a matching task, we found that participants were able to discriminate normal and Thatcherized versions of the same face when they were presented in an upright orientation, but not when the images were inverted. Next, we showed that the effect of inversion was also apparent when only the eye region or only the mouth region was visible. These results demonstrate that a key component of the Thatcher illusion is to be found in orientation-specific encoding of the expressive features (eyes and mouth) of the face. © 2014 ARVO.
Configural and component processing in simultaneous and sequential lineup procedures.
Flowe, Heather D; Smith, Harriet M J; Karoğlu, Nilda; Onwuegbusi, Tochukwu O; Rai, Lovedeep
2016-01-01
Configural processing supports accurate face recognition, yet it has never been examined within the context of criminal identification lineups. We tested, using the inversion paradigm, the role of configural processing in lineups. Recent research has found that face discrimination accuracy in lineups is better in a simultaneous compared to a sequential lineup procedure. Therefore, we compared configural processing in simultaneous and sequential lineups to examine whether there are differences. We had participants view a crime video, and then they attempted to identify the perpetrator from a simultaneous or sequential lineup. The test faces were presented either upright or inverted, as previous research has shown that inverting test faces disrupts configural processing. The size of the inversion effect for faces was the same across lineup procedures, indicating that configural processing underlies face recognition in both procedures. Discrimination accuracy was comparable across lineup procedures in both the upright and inversion condition. Theoretical implications of the results are discussed.
Wiese, Holger
2013-01-01
We are typically more accurate at remembering own- than other-race faces. This “own-race bias” has been suggested to result from enhanced expertise with and more efficient perceptual processing of own-race than other-race faces. In line with this idea, the N170, an event-related potential correlate of face perception, has been repeatedly found to be larger for other-race faces. Other studies, however, found no difference in N170 amplitude for faces from diverse ethnic groups. The present study tested whether these seemingly incongruent findings can be explained by varying task demands. European participants were presented with upright and inverted European and Asian faces (as well as European and Asian houses), and asked to either indicate the ethnicity or the orientation of the stimuli. Larger N170s for other-race faces were observed in the ethnicity but not in the orientation task, suggesting that the necessity to process facial category information is a minimum prerequisite for the occurrence of the effect. In addition, N170 inversion effects, with larger amplitudes for inverted relative to upright stimuli, were more pronounced for own- relative to other-race faces in both tasks. Overall, the present findings suggest that the occurrence of ethnicity effects in N170 for upright faces depends on the amount of facial detail required for the task at hand. At the same time, the larger inversion effects for own- than other-race faces occur independent of task and may reflect the fine-tuning of perceptual processing to faces of maximum expertise. PMID:24399955
Van Belle, Goedele; Vanduffel, Wim; Rossion, Bruno; Vogels, Rufin
2014-01-01
It is widely believed that face processing in the primate brain occurs in a network of category-selective cortical regions. Combined functional MRI (fMRI)-single-cell recording studies in macaques have identified high concentrations of neurons that respond more to faces than objects within face-selective patches. However, cells with a preference for faces over objects are also found scattered throughout inferior temporal (IT) cortex, raising the question whether face-selective cells inside and outside of the face patches differ functionally. Here, we compare the properties of face-selective cells inside and outside of face-selective patches in the IT cortex by means of an image manipulation that reliably disrupts behavior toward face processing: inversion. We recorded IT neurons from two fMRI-defined face-patches (ML and AL) and a region outside of the face patches (herein labeled OUT) during upright and inverted face stimulation. Overall, turning faces upside down reduced the firing rate of face-selective cells. However, there were differences among the recording regions. First, the reduced neuronal response for inverted faces was independent of stimulus position, relative to fixation, in the face-selective patches (ML and AL) only. Additionally, the effect of inversion for face-selective cells in ML, but not those in AL or OUT, was impervious to whether the neurons were initially searched for using upright or inverted stimuli. Collectively, these results show that face-selective cells differ in their functional characteristics depending on their anatomicofunctional location, suggesting that upright faces are preferably coded by face-selective cells inside but not outside of the fMRI-defined face-selective regions of the posterior IT cortex. PMID:25520434
ERIC Educational Resources Information Center
Crookes, Kate; Hayward, William G.
2012-01-01
Presenting a face inverted (upside down) disrupts perceptual sensitivity to the spacing between the features. Recently, it has been shown that this disruption is greater for vertical than horizontal changes in eye position. One explanation for this effect proposed that inversion disrupts the processing of long-range (e.g., eye-to-mouth distance)…
Combined effects of inversion and feature removal on N170 responses elicited by faces and car fronts
Kloth, Nadine; Itier, Roxane J.; Schweinberger, Stefan R.
2014-01-01
The face-sensitive N170 is typically enhanced for inverted compared to upright faces. Itier, Alain, Sedore, and McIntosh (2007) recently suggested that this N170 inversion effect is mainly driven by the eye region which becomes salient when the face configuration is disrupted. Here we tested whether similar effects could be observed with non-face objects that are structurally similar to faces in terms of possessing a homogeneous within-class first-order feature configuration. We presented upright and inverted pictures of intact car fronts, car fronts without lights, and isolated lights, in addition to analogous face conditions. Upright cars elicited substantial N170 responses of similar amplitude to those evoked by upright faces. In strong contrast to face conditions however, the car-elicited N170 was mainly driven by the global shape rather than the presence or absence of lights, and was dramatically reduced for isolated lights. Overall, our data confirm a differential influence of the eye region in upright and inverted faces. Results for car fronts do not suggest similar interactive encoding of eye-like features and configuration for non-face objects, even when these objects possess a similar feature configuration as faces. PMID:23485023
Leube, Dirk T; Yoon, Hyo Woon; Rapp, Alexander; Erb, Michael; Grodd, Wolfgang; Bartels, Mathias; Kircher, Tilo T J
2003-05-22
Perception of upright faces relies on configural processing. Therefore recognition of inverted, compared to upright faces is impaired. In a functional magnetic resonance imaging experiment we investigated the neural correlate of a face inversion task. Thirteen healthy subjects were presented with a equal number of upright and inverted faces alternating with a low level baseline with an upright and inverted picture of an abstract symbol. Brain activation was calculated for upright minus inverted faces. For this differential contrast, we found a signal change in the right superior temporal sulcus and right insula. Configural properties are processed in a network comprising right superior temporal and insular cortex.
Discrimination of human and dog faces and inversion responses in domestic dogs (Canis familiaris).
Racca, Anaïs; Amadei, Eleonora; Ligout, Séverine; Guo, Kun; Meints, Kerstin; Mills, Daniel
2010-05-01
Although domestic dogs can respond to many facial cues displayed by other dogs and humans, it remains unclear whether they can differentiate individual dogs or humans based on facial cues alone and, if so, whether they would demonstrate the face inversion effect, a behavioural hallmark commonly used in primates to differentiate face processing from object processing. In this study, we first established the applicability of the visual paired comparison (VPC or preferential looking) procedure for dogs using a simple object discrimination task with 2D pictures. The animals demonstrated a clear looking preference for novel objects when simultaneously presented with prior-exposed familiar objects. We then adopted this VPC procedure to assess their face discrimination and inversion responses. Dogs showed a deviation from random behaviour, indicating discrimination capability when inspecting upright dog faces, human faces and object images; but the pattern of viewing preference was dependent upon image category. They directed longer viewing time at novel (vs. familiar) human faces and objects, but not at dog faces, instead, a longer viewing time at familiar (vs. novel) dog faces was observed. No significant looking preference was detected for inverted images regardless of image category. Our results indicate that domestic dogs can use facial cues alone to differentiate individual dogs and humans and that they exhibit a non-specific inversion response. In addition, the discrimination response by dogs of human and dog faces appears to differ with the type of face involved.
Famous face recognition, face matching, and extraversion.
Lander, Karen; Poyarekar, Siddhi
2015-01-01
It has been previously established that extraverts who are skilled at interpersonal interaction perform significantly better than introverts on a face-specific recognition memory task. In our experiment we further investigate the relationship between extraversion and face recognition, focusing on famous face recognition and face matching. Results indicate that more extraverted individuals perform significantly better on an upright famous face recognition task and show significantly larger face inversion effects. However, our results did not find an effect of extraversion on face matching or inverted famous face recognition.
Face perception is tuned to horizontal orientation in the N170 time window.
Jacques, Corentin; Schiltz, Christine; Goffaux, Valerie
2014-02-07
The specificity of face perception is thought to reside both in its dramatic vulnerability to picture-plane inversion and its strong reliance on horizontally oriented image content. Here we asked when in the visual processing stream face-specific perception is tuned to horizontal information. We measured the behavioral performance and scalp event-related potentials (ERP) when participants viewed upright and inverted images of faces and cars (and natural scenes) that were phase-randomized in a narrow orientation band centered either on vertical or horizontal orientation. For faces, the magnitude of the inversion effect (IE) on behavioral discrimination performance was significantly reduced for horizontally randomized compared to vertically or nonrandomized images, confirming the importance of horizontal information for the recruitment of face-specific processing. Inversion affected the processing of nonrandomized and vertically randomized faces early, in the N170 time window. In contrast, the magnitude of the N170 IE was much smaller for horizontally randomized faces. The present research indicates that the early face-specific neural representations are preferentially tuned to horizontal information and offers new perspectives for a description of the visual information feeding face-specific perception.
It's All in Your Head: Why Is the Body Inversion Effect Abolished for Headless Bodies?
ERIC Educational Resources Information Center
Yovel, Galit; Pelc, Tatiana; Lubetzky, Ida
2010-01-01
It has been recently argued that human bodies are processed by a specialized processing mechanism. Central evidence was that body inversion reduces recognition abilities (body inversion effect; BIE) as much as it does for faces, but more than for other objects. Here we showed that the BIE is markedly reduced for headless bodies and examined the…
Kloth, Nadine; Itier, Roxane J; Schweinberger, Stefan R
2013-04-01
The face-sensitive N170 is typically enhanced for inverted compared to upright faces. Itier, Alain, Sedore, and McIntosh (2007) recently suggested that this N170 inversion effect is mainly driven by the eye region which becomes salient when the face configuration is disrupted. Here we tested whether similar effects could be observed with non-face objects that are structurally similar to faces in terms of possessing a homogeneous within-class first-order feature configuration. We presented upright and inverted pictures of intact car fronts, car fronts without lights, and isolated lights, in addition to analogous face conditions. Upright cars elicited substantial N170 responses of similar amplitude to those evoked by upright faces. In strong contrast to face conditions however, the car-elicited N170 was mainly driven by the global shape rather than the presence or absence of lights, and was dramatically reduced for isolated lights. Overall, our data confirm a differential influence of the eye region in upright and inverted faces. Results for car fronts do not suggest similar interactive encoding of eye-like features and configuration for non-face objects, even when these objects possess a similar feature configuration as faces. Copyright © 2013 Elsevier Inc. All rights reserved.
Opposite effects on facial morphology due to gene dosage sensitivity.
Hammond, Peter; McKee, Shane; Suttie, Michael; Allanson, Judith; Cobben, Jan-Maarten; Maas, Saskia M; Quarrell, Oliver; Smith, Ann C M; Lewis, Suzanne; Tassabehji, May; Sisodiya, Sanjay; Mattina, Teresa; Hennekam, Raoul
2014-09-01
Sequencing technology is increasingly demonstrating the impact of genomic copy number variation (CNV) on phenotypes. Opposing variation in growth, head size, cognition and behaviour is known to result from deletions and reciprocal duplications of some genomic regions. We propose normative inversion of face shape, opposing difference from a matched norm, as a basis for investigating the effects of gene dosage on craniofacial development. We use dense surface modelling techniques to match any face (or part of a face) to a facial norm of unaffected individuals of matched age, sex and ethnicity and then we reverse the individual's face shape differences from the matched norm to produce the normative inversion. We demonstrate for five genomic regions, 4p16.3, 7q11.23, 11p15, 16p13.3 and 17p11.2, that such inversion for individuals with a duplication or (epi)-mutation produces facial forms remarkably similar to those associated with a deletion or opposite (epi-)mutation of the same region, and vice versa. The ability to visualise and quantify face shape effects of gene dosage is of major benefit for determining whether a CNV is the cause of the phenotype of an individual and for predicting reciprocal consequences. It enables face shape to be used as a relatively simple and inexpensive functional analysis of the gene(s) involved.
Disordered high-frequency oscillation in face processing in schizophrenia patients
Liu, Miaomiao; Pei, Guangying; Peng, Yinuo; Wang, Changming; Yan, Tianyi; Wu, Jinglong
2018-01-01
Abstract Schizophrenia is a complex disorder characterized by marked social dysfunctions, but the neural mechanism underlying this deficit is unknown. To investigate whether face-specific perceptual processes are influenced in schizophrenia patients, both face detection and configural analysis were assessed in normal individuals and schizophrenia patients by recording electroencephalogram (EEG) data. Here, a face processing model was built based on the frequency oscillations, and the evoked power (theta, alpha, and beta bands) and the induced power (gamma bands) were recorded while the subjects passively viewed face and nonface images presented in upright and inverted orientations. The healthy adults showed a significant face-specific effect in the alpha, beta, and gamma bands, and an inversion effect was observed in the gamma band in the occipital lobe and right temporal lobe. Importantly, the schizophrenia patients showed face-specific deficits in the low-frequency beta and gamma bands, and the face inversion effect in the gamma band was absent from the occipital lobe. All these results revealed face-specific processing in patients due to the disorder of high-frequency EEG, providing additional evidence to enrich future studies investigating neural mechanisms and serving as a marked diagnostic basis. PMID:29419668
ERIC Educational Resources Information Center
Goffaux, Valerie; Rossion, Bruno
2007-01-01
Upside-down inversion disrupts the processing of spatial relations between the features of a face, while largely preserving local feature analysis. However, recent studies on face inversion failed to observe a clear dissociation between relational and featural processing. To resolve these discrepancies and clarify how inversion affects face…
ERIC Educational Resources Information Center
Cleary, Laura; Brady, Nuala; Fitzgerald, Michael; Gallagher, Louise
2015-01-01
Impaired face perception in autism spectrum disorders is thought to reflect a perceptual style characterized by componential rather than configural processing of faces. This study investigated face processing in adolescents with autism spectrum disorders using the Thatcher illusion, a perceptual phenomenon exhibiting "inversion effects"…
Matheson, H E; Bilsbury, T G; McMullen, P A
2012-03-01
A large body of research suggests that faces are processed by a specialized mechanism within the human visual system. This specialized mechanism is made up of subprocesses (Maurer, LeGrand, & Mondloch, 2002). One subprocess, called second- order relational processing, analyzes the metric distances between face parts. Importantly, it is well established that other-race faces and contrast-reversed faces are associated with impaired performance on numerous face processing tasks. Here, we investigated the specificity of second-order relational processing by testing how this process is applied to faces of different race and photographic contrast. Participants completed a feature displacement discrimination task, directly measuring the sensitivity to second-order relations between face parts. Across three experiments we show that, despite absolute differences in sensitivity in some conditions, inversion impaired performance in all conditions. The presence of robust inversion effects for all faces suggests that second-order relational processing can be applied to faces of different race and photographic contrast.
Face inversion increases attractiveness.
Leder, Helmut; Goller, Juergen; Forster, Michael; Schlageter, Lena; Paul, Matthew A
2017-07-01
Assessing facial attractiveness is a ubiquitous, inherent, and hard-wired phenomenon in everyday interactions. As such, it has highly adapted to the default way that faces are typically processed: viewing faces in upright orientation. By inverting faces, we can disrupt this default mode, and study how facial attractiveness is assessed. Faces, rotated at 90 (tilting to either side) and 180°, were rated on attractiveness and distinctiveness scales. For both orientations, we found that faces were rated more attractive and less distinctive than upright faces. Importantly, these effects were more pronounced for faces rated low in upright orientation, and smaller for highly attractive faces. In other words, the less attractive a face was, the more it gained in attractiveness by inversion or rotation. Based on these findings, we argue that facial attractiveness assessments might not rely on the presence of attractive facial characteristics, but on the absence of distinctive, unattractive characteristics. These unattractive characteristics are potentially weighed against an individual, attractive prototype in assessing facial attractiveness. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
Jemel, Boutheina; Coutya, Julie; Langer, Caroline; Roy, Sylvain
2009-01-01
Background While there is a general agreement that picture-plane inversion is more detrimental to face processing than to other seemingly complex visual objects, the origin of this effect is still largely debatable. Here, we address the question of whether face inversion reflects a quantitative or a qualitative change in processing mode by investigating the pattern of event-related potential (ERP) response changes with picture plane rotation of face and house pictures. Thorough analyses of topographical (Scalp Current Density maps, SCD) and dipole source modeling were also conducted. Results We find that whilst stimulus orientation affected in a similar fashion participants' response latencies to make face and house decisions, only the ERPs in the N170 latency range were modulated by picture plane rotation of faces. The pattern of N170 amplitude and latency enhancement to misrotated faces displayed a curvilinear shape with an almost linear increase for rotations from 0° to 90° and a dip at 112.5° up to 180° rotations. A similar discontinuity function was also described for SCD occipito-temporal and temporal current foci with no topographic distribution changes, suggesting that upright and misrotated faces activated similar brain sources. This was confirmed by dipole source analyses showing the involvement of bilateral sources in the fusiform and middle occipital gyri, the activity of which was differentially affected by face rotation. Conclusion Our N170 findings provide support for both the quantitative and qualitative accounts for face rotation effects. Although the qualitative explanation predicted the curvilinear shape of N170 modulations by face misrotations, topographical and source modeling findings suggest that the same brain regions, and thus the same mechanisms, are probably at work when processing upright and rotated faces. Taken collectively, our results indicate that the same processing mechanisms may be involved across the whole range of face orientations, but would operate in a non-linear fashion. Finally, the response tuning of the N170 to rotated faces extends previous reports and further demonstrates that face inversion affects perceptual analyses of faces, which is reflected within the time range of the N170 component. PMID:19691846
Jemel, Boutheina; Coutya, Julie; Langer, Caroline; Roy, Sylvain
2009-08-19
While there is a general agreement that picture-plane inversion is more detrimental to face processing than to other seemingly complex visual objects, the origin of this effect is still largely debatable. Here, we address the question of whether face inversion reflects a quantitative or a qualitative change in processing mode by investigating the pattern of event-related potential (ERP) response changes with picture plane rotation of face and house pictures. Thorough analyses of topographical (Scalp Current Density maps, SCD) and dipole source modeling were also conducted. We find that whilst stimulus orientation affected in a similar fashion participants' response latencies to make face and house decisions, only the ERPs in the N170 latency range were modulated by picture plane rotation of faces. The pattern of N170 amplitude and latency enhancement to misrotated faces displayed a curvilinear shape with an almost linear increase for rotations from 0 degrees to 90 degrees and a dip at 112.5 degrees up to 180 degrees rotations. A similar discontinuity function was also described for SCD occipito-temporal and temporal current foci with no topographic distribution changes, suggesting that upright and misrotated faces activated similar brain sources. This was confirmed by dipole source analyses showing the involvement of bilateral sources in the fusiform and middle occipital gyri, the activity of which was differentially affected by face rotation. Our N170 findings provide support for both the quantitative and qualitative accounts for face rotation effects. Although the qualitative explanation predicted the curvilinear shape of N170 modulations by face misrotations, topographical and source modeling findings suggest that the same brain regions, and thus the same mechanisms, are probably at work when processing upright and rotated faces. Taken collectively, our results indicate that the same processing mechanisms may be involved across the whole range of face orientations, but would operate in a non-linear fashion. Finally, the response tuning of the N170 to rotated faces extends previous reports and further demonstrates that face inversion affects perceptual analyses of faces, which is reflected within the time range of the N170 component.
Environmental Inversion Effects in Face Perception
ERIC Educational Resources Information Center
Davidenko, Nicolas; Flusberg, Stephen J.
2012-01-01
Visual processing is highly sensitive to stimulus orientation; for example, face perception is drastically worse when faces are oriented inverted vs. upright. However, stimulus orientation must be established in relation to a particular reference frame, and in most studies, several reference frames are conflated. Which reference frame(s) matter in…
Turning Configural Processing Upside Down: Part and Whole Body Postures
ERIC Educational Resources Information Center
Reed, Catherine L.; Stone, Valerie E.; Grubb, Jefferson D.; McGoldrick, John E.
2006-01-01
Like faces, body postures are susceptible to an inversion effect in untrained viewers. The inversion effect may be indicative of configural processing, but what kind of configural processing is used for the recognition of body postures must be specified. The information available in the body stimulus was manipulated. The presence and magnitude of…
Inversion effect in the visual processing of Chinese character: an fMRI study.
Zhao, Jizheng; Liu, Jiangang; Li, Jun; Liang, Jimin; Feng, Lu; Ai, Lin; Tian, Jie
2010-07-05
Chinese people engage long-term processing of characters. It has been demonstrated that the presented orientation affects the perception of several types of stimuli when people have possessed expertise with them, e.g. face, body, and scene. However, the influence of inversion on the neural mechanism of Chinese character processing has not been sufficiently discussed. In the present study, a functional magnetic resonance imaging (fMRI) experiment is performed to examine the effect of inversion on Chinese character processing, which employs Chinese character, face and house as stimuli. The region of interest analysis demonstrates inversion leads to neural response increases for Chinese character in left fusiform character-preferential area, bilateral fusiform object-preferential area and bilateral occipital object-preferential area, and such inversion-caused changes in the response pattern of characters processing are highly similar to those of faces processing but quiet different from those of houses processing. Whole brain analysis reveals the upright characters recruit several language regions for phonology and semantic processing, however, the inverted characters activated extensive regions related to the visual information processing. Our findings reveal a shift from the character-preferential processing route to the generic object processing steam within visual cortex when the characters are inverted, and suggest that different mechanisms may underlie the upright and the inverted Chinese character, respectively. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.
The effects of facial color and inversion on the N170 event-related potential (ERP) component.
Minami, T; Nakajima, K; Changvisommid, L; Nakauchi, S
2015-12-17
Faces are important for social interaction because much can be perceived from facial details, including a person's race, age, and mood. Recent studies have shown that both configural (e.g. face shape and inversion) and surface information (e.g. surface color and reflectance properties) are important for face perception. Therefore, the present study examined the effects of facial color and inverted face properties on event-related potential (ERP) responses, particularly the N170 component. Stimuli consisted of natural and bluish-colored faces. Faces were presented in both upright and upside down orientations. An ANOVA was used to analyze N170 amplitudes and verify the effects of the main independent variables. Analysis of N170 amplitude revealed the significant interactions between stimulus orientation and color. Subsequent analysis indicated that N170 was larger for bluish-colored faces than natural-colored faces, and N170 to natural-colored faces was larger in response to inverted stimulus as compared to upright stimulus. Additionally, a multivariate pattern analysis (MVPA) investigated face-processing dynamics without any prior assumptions. Results distinguished, above chance, both facial color and orientation from single-trial electroencephalogram (EEG) signals. Decoding performance for color classification of inverted faces was significantly diminished as compared to an upright orientation. This suggests that processing orientation is predominant over facial color. Taken together, the present findings elucidate the temporal and spatial distribution of orientation and color processing during face processing. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.
Making heads turn: the effect of familiarity and stimulus rotation on a gender-classification task.
Stevenage, Sarah V; Osborne, Cara D
2006-01-01
Recent work has demonstrated that facial familiarity can moderate the influence of inversion when completing a configural processing task. Here, we examine whether familiarity interacts with intermediate angles of orientation in the same way that it interacts with inversion. Participants were asked to make a gender classification to familiar and unfamiliar faces shown at seven angles of orientation. Speed and accuracy of performance were assessed for stimuli presented (i) as whole faces and (ii) as internal features. When presented as whole faces, the task was easy, as revealed by ceiling levels of accuracy and no effect of familiarity or angle of rotation on response times. However, when stimuli were presented as internal features, an influence of facial familiarity was evident. Unfamiliar faces showed no increase in difficulty across angle of rotation, whereas familiar faces showed a marked increase in difficulty across angle, which was explained by significant linear and cubic trends in the data. Results were interpreted in terms of the benefit gained from a mental representation when face processing was impaired by stimulus rotation.
The Effects of Inversion and Familiarity on Face versus Body Cues to Person Recognition
ERIC Educational Resources Information Center
Robbins, Rachel A.; Coltheart, Max
2012-01-01
Extensive research has focused on face recognition, and much is known about this topic. However, much of this work seems to be based on an assumption that faces are the most important aspect of person recognition. Here we test this assumption in two experiments. We show that when viewers are forced to choose, they "do" use the face more than the…
The faces of development: a review of early face processing over childhood.
Taylor, M J; Batty, M; Itier, R J
2004-10-01
The understanding of the adult proficiency in recognizing and extracting information from faces is still limited despite the number of studies over the last decade. Our knowledge on the development of these capacities is even more restricted, as only a handful of such studies exist. Here we present a combined reanalysis of four ERP studies in children from 4 to 15 years of age and adults (n = 424, across the studies), which investigated face processing in implicit and explicit tasks. We restricted these analyses to what was common across studies: early ERP components and upright face processing across all four studies and the inversion effect, investigated in three of the studies. These data demonstrated that processing faces implicates very rapid neural activity, even in young children--at the P1 component--with protracted age-related change in both P1 and N170, that were sensitive to the different task demands. Inversion produced latency and amplitude effects on the P1 from the youngest group, but on N170 only starting in mid childhood. These developmental data suggest that there are functionally different sources of the P1 and N170, related to the processing of different aspects of faces.
Face inversion and acquired prosopagnosia reduce the size of the perceptual field of view.
Van Belle, Goedele; Lefèvre, Philippe; Rossion, Bruno
2015-03-01
Using a gaze-contingent morphing approach, we asked human observers to choose one of two faces that best matched the identity of a target face: one face corresponded to the reference face's fixated part only (e.g., one eye), the other corresponded to the unfixated area of the reference face. The face corresponding to the fixated part was selected significantly more frequently in the inverted than in the upright orientation. This observation provides evidence that face inversion reduces an observer's perceptual field of view, even when both upright and inverted faces are displayed at full view and there is no performance difference between these conditions. It rules out an account of the drop of performance for inverted faces--one of the most robust effects in experimental psychology--in terms of a mere difference in local processing efficiency. A brain-damaged patient with pure prosopagnosia, viewing only upright faces, systematically selected the face corresponding to the fixated part, as if her perceptual field was reduced relative to normal observers. Altogether, these observations indicate that the absence of visual knowledge reduces the perceptual field of view, supporting an indirect view of visual perception. Copyright © 2014 Elsevier B.V. All rights reserved.
Integration of internal and external facial features in 8- to 10-year-old children and adults.
Meinhardt-Injac, Bozana; Persike, Malte; Meinhardt, Günter
2014-06-01
Investigation of whole-part and composite effects in 4- to 6-year-old children gave rise to claims that face perception is fully mature within the first decade of life (Crookes & McKone, 2009). However, only internal features were tested, and the role of external features was not addressed, although external features are highly relevant for holistic face perception (Sinha & Poggio, 1996; Axelrod & Yovel, 2010, 2011). In this study, 8- to 10-year-old children and adults performed a same-different matching task with faces and watches. In this task participants attended to either internal or external features. Holistic face perception was tested using a congruency paradigm, in which face and non-face stimuli either agreed or disagreed in both features (congruent contexts) or just in the attended ones (incongruent contexts). In both age groups, pronounced context congruency and inversion effects were found for faces, but not for watches. These findings indicate holistic feature integration for faces. While inversion effects were highly similar in both age groups, context congruency effects were stronger for children. Moreover, children's face matching performance was generally better when attending to external compared to internal features. Adults tended to perform better when attending to internal features. Our results indicate that both adults and 8- to 10-year-old children integrate external and internal facial features into holistic face representations. However, in children's face representations external features are much more relevant. These findings suggest that face perception is holistic but still not adult-like at the end of the first decade of life. Copyright © 2014 Elsevier B.V. All rights reserved.
The other-race effect does not rely on memory: Evidence from a matching task.
Megreya, Ahmed M; White, David; Burton, A Mike
2011-08-01
Viewers are typically better at remembering faces from their own race than from other races; however, it is not yet established whether this effect is due to memorial or perceptual processes. In this study, UK and Egyptian viewers were given a simultaneous face-matching task, in which the target faces were presented upright or upside down. As with previous research using face memory tasks, participants were worse at matching other-race faces than own-race faces and showed a stronger face inversion effect for own-race faces. However, subjects' performance on own and other-race faces was highly correlated. These data provide strong evidence that difficulty in perceptual encoding of unfamiliar faces contributes substantially to the other-race effect and that accounts based entirely on memory cannot capture the full data. Implications for forensic settings are also discussed.
Beyond U-Shaped Development in Infants' Processing of Faces: An Information-Processing Account
ERIC Educational Resources Information Center
Cashon, Cara H.; Cohen, Leslie B.
2004-01-01
The development of the "inversion" effect in face processing was examined in infants 3 to 6 months of age by testing their integration of the internal and external features of upright and inverted faces using a variation of the "switch" visual habituation paradigm. When combined with previous findings showing that 7-month-olds use integrative…
Marinkovic, Ksenija; Courtney, Maureen G.; Witzel, Thomas; Dale, Anders M.; Halgren, Eric
2014-01-01
Although a crucial role of the fusiform gyrus (FG) in face processing has been demonstrated with a variety of methods, converging evidence suggests that face processing involves an interactive and overlapping processing cascade in distributed brain areas. Here we examine the spatio-temporal stages and their functional tuning to face inversion, presence and configuration of inner features, and face contour in healthy subjects during passive viewing. Anatomically-constrained magnetoencephalography (aMEG) combines high-density whole-head MEG recordings and distributed source modeling with high-resolution structural MRI. Each person's reconstructed cortical surface served to constrain noise-normalized minimum norm inverse source estimates. The earliest activity was estimated to the occipital cortex at ~100 ms after stimulus onset and was sensitive to an initial coarse level visual analysis. Activity in the right-lateralized ventral temporal area (inclusive of the FG) peaked at ~160 ms and was largest to inverted faces. Images containing facial features in the veridical and rearranged configuration irrespective of the facial outline elicited intermediate level activity. The M160 stage may provide structural representations necessary for downstream distributed areas to process identity and emotional expression. However, inverted faces additionally engaged the left ventral temporal area at ~180 ms and were uniquely subserved by bilateral processing. This observation is consistent with the dual route model and spared processing of inverted faces in prosopagnosia. The subsequent deflection, peaking at ~240 ms in the anterior temporal areas bilaterally, was largest to normal, upright faces. It may reflect initial engagement of the distributed network subserving individuation and familiarity. These results support dynamic models suggesting that processing of unfamiliar faces in the absence of a cognitive task is subserved by a distributed and interactive neural circuit. PMID:25426044
The Promiscuity of [beta]-Strand Pairing Allows for Rational Design of [beta]-Sheet Face Inversion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Makabe, Koki; Koide, Shohei
2009-06-17
Recent studies suggest the dominant role of main-chain H-bond formation in specifying {beta}-sheet topology. Its essentially sequence-independent nature implies a large degree of freedom in designing {beta}-sheet-based nanomaterials. Here we show rational design of {beta}-sheet face inversions by incremental deletions of {beta}-strands from the single-layer {beta}-sheet of Borrelia outer surface protein A. We show that a {beta}-sheet structure can be maintained when a large number of native contacts are removed and that one can design large-scale conformational transitions of a {beta}-sheet such as face inversion by exploiting the promiscuity of strand-strand interactions. High-resolution X-ray crystal structures confirmed the success ofmore » the design and supported the importance of main-chain H-bonds in determining {beta}-sheet topology. This work suggests a simple but effective strategy for designing and controlling nanomaterials based on {beta}-rich peptide self-assemblies.« less
Phasic alertness enhances processing of face and non-face stimuli in congenital prosopagnosia.
Tanzer, Michal; Weinbach, Noam; Mardo, Elite; Henik, Avishai; Avidan, Galia
2016-08-01
Congenital prosopagnosia (CP) is a severe face processing impairment that occurs in the absence of any obvious brain damage and has often been associated with a more general deficit in deriving holistic relations between facial features or even between non-face shape dimensions. Here we further characterized this deficit and examined a potential way to ameliorate it. To this end we manipulated phasic alertness using alerting cues previously shown to modulate attention and enhance global processing of visual stimuli in normal observers. Specifically, we first examined whether individuals with CP, similarly to controls, would show greater global processing when exposed to an alerting cue in the context of a non-facial task (Navon global/local task). We then explored the effect of an alerting cue on face processing (upright/inverted face discrimination). Confirming previous findings, in the absence of alerting cues, controls showed a typical global bias in the Navon task and an inversion effect indexing holistic processing in the upright/inverted task, while CP failed to show these effects. Critically, when alerting cues preceded the experimental trials, both groups showed enhanced global interference and a larger inversion effect. These results suggest that phasic alertness may modulate visual processing and consequently, affect global/holistic perception. Hence, these findings further reinforce the notion that global/holistic processing may serve as a possible mechanism underlying the face processing deficit in CP. Moreover, they imply a possible route for enhancing face processing in individuals with CP and thus shed new light on potential amelioration of this disorder. Copyright © 2016 Elsevier Ltd. All rights reserved.
Face-space: A unifying concept in face recognition research.
Valentine, Tim; Lewis, Michael B; Hills, Peter J
2016-10-01
The concept of a multidimensional psychological space, in which faces can be represented according to their perceived properties, is fundamental to the modern theorist in face processing. Yet the idea was not clearly expressed until 1991. The background that led to the development of face-space is explained, and its continuing influence on theories of face processing is discussed. Research that has explored the properties of the face-space and sought to understand caricature, including facial adaptation paradigms, is reviewed. Face-space as a theoretical framework for understanding the effect of ethnicity and the development of face recognition is evaluated. Finally, two applications of face-space in the forensic setting are discussed. From initially being presented as a model to explain distinctiveness, inversion, and the effect of ethnicity, face-space has become a central pillar in many aspects of face processing. It is currently being developed to help us understand adaptation effects with faces. While being in principle a simple concept, face-space has shaped, and continues to shape, our understanding of face perception.
Webb, Sara Jane; Jones, Emily; Merkle, Kristen; Kamara, Dana; Bavaro, Joshua; Aylward, Elizabeth; Dawson, Geraldine
2013-01-01
The effect of expertise training with faces was studied in adults with ASD who showed initial impairment in face recognition. Participants were randomly assigned to a computerized training program involving either faces or houses. Pre- and post-testing included standardized and experimental measures of behavior and event-related brain potentials (ERPs), as well as interviews after training. After training, all participants met behavioral criteria for expertise with the specific stimuli on which they received training. Scores on standardized measures improved after training for both groups, but only the face training group showed an increased face inversion effect behaviorally and electrophysiological changes to faces in the P100 component. These findings suggest that individuals with ASD can gain expertise in face processing through training. PMID:21484517
Proietti, Valentina; Pisacane, Antonella; Macchi Cassia, Viola
2013-01-01
Just like other face dimensions, age influences the way faces are processed by adults as well as by children. However, it remains unclear under what conditions exactly such influence occurs at both ages, in that there is some mixed evidence concerning the presence of a systematic processing advantage for peer faces (own-age bias) across the lifespan. Inconsistency in the results may stem from the fact that the individual’s face representation adapts to represent the most predominant age traits of the faces present in the environment, which is reflective of the individual’s specific living conditions and social experience. In the current study we investigated the processing of younger and older adult faces in two groups of adults (Experiment 1) and two groups of 3-year-old children (Experiment 2) who accumulated different amounts of experience with elderly people. Contact with elderly adults influenced the extent to which both adult and child participants showed greater discrimination abilities and stronger sensitivity to configural/featural cues in younger versus older adult faces, as measured by the size of the inversion effect. In children, the size of the inversion effect for older adult faces was also significantly correlated with the amount of contact with elderly people. These results show that, in both adults and children, visual experience with older adult faces can tune perceptual processing strategies to the point of abolishing the discrimination disadvantage that participants typically manifest for those faces in comparison to younger adult faces. PMID:23460867
Perception and Processing of Faces in the Human Brain Is Tuned to Typical Feature Locations
Schwarzkopf, D. Samuel; Alvarez, Ivan; Lawson, Rebecca P.; Henriksson, Linda; Kriegeskorte, Nikolaus; Rees, Geraint
2016-01-01
Faces are salient social stimuli whose features attract a stereotypical pattern of fixations. The implications of this gaze behavior for perception and brain activity are largely unknown. Here, we characterize and quantify a retinotopic bias implied by typical gaze behavior toward faces, which leads to eyes and mouth appearing most often in the upper and lower visual field, respectively. We found that the adult human visual system is tuned to these contingencies. In two recognition experiments, recognition performance for isolated face parts was better when they were presented at typical, rather than reversed, visual field locations. The recognition cost of reversed locations was equal to ∼60% of that for whole face inversion in the same sample. Similarly, an fMRI experiment showed that patterns of activity evoked by eye and mouth stimuli in the right inferior occipital gyrus could be separated with significantly higher accuracy when these features were presented at typical, rather than reversed, visual field locations. Our findings demonstrate that human face perception is determined not only by the local position of features within a face context, but by whether features appear at the typical retinotopic location given normal gaze behavior. Such location sensitivity may reflect fine-tuning of category-specific visual processing to retinal input statistics. Our findings further suggest that retinotopic heterogeneity might play a role for face inversion effects and for the understanding of conditions affecting gaze behavior toward faces, such as autism spectrum disorders and congenital prosopagnosia. SIGNIFICANCE STATEMENT Faces attract our attention and trigger stereotypical patterns of visual fixations, concentrating on inner features, like eyes and mouth. Here we show that the visual system represents face features better when they are shown at retinal positions where they typically fall during natural vision. When facial features were shown at typical (rather than reversed) visual field locations, they were discriminated better by humans and could be decoded with higher accuracy from brain activity patterns in the right occipital face area. This suggests that brain representations of face features do not cover the visual field uniformly. It may help us understand the well-known face-inversion effect and conditions affecting gaze behavior toward faces, such as prosopagnosia and autism spectrum disorders. PMID:27605606
Perceptual expertise in forensic facial image comparison
White, David; Phillips, P. Jonathon; Hahn, Carina A.; Hill, Matthew; O'Toole, Alice J.
2015-01-01
Forensic facial identification examiners are required to match the identity of faces in images that vary substantially, owing to changes in viewing conditions and in a person's appearance. These identifications affect the course and outcome of criminal investigations and convictions. Despite calls for research on sources of human error in forensic examination, existing scientific knowledge of face matching accuracy is based, almost exclusively, on people without formal training. Here, we administered three challenging face matching tests to a group of forensic examiners with many years' experience of comparing face images for law enforcement and government agencies. Examiners outperformed untrained participants and computer algorithms, thereby providing the first evidence that these examiners are experts at this task. Notably, computationally fusing responses of multiple experts produced near-perfect performance. Results also revealed qualitative differences between expert and non-expert performance. First, examiners' superiority was greatest at longer exposure durations, suggestive of more entailed comparison in forensic examiners. Second, experts were less impaired by image inversion than non-expert students, contrasting with face memory studies that show larger face inversion effects in high performers. We conclude that expertise in matching identity across unfamiliar face images is supported by processes that differ qualitatively from those supporting memory for individual faces. PMID:26336174
Impaired holistic processing in congenital prosopagnosia
Avidan, Galia; Tanzer, Michal; Behrmann, Marlene
2011-01-01
It has long been argued that face processing requires disproportionate reliance on holistic or configural processing, relative to that required for non-face object recognition, and that a disruption of such holistic processing may be causally implicated in prosopagnosia. Previously, we demonstrated that individuals with congenital prosopagnosia (CP) did not show the normal face inversion effect (better performance for upright compared to inverted faces) and evinced a local (rather than the normal global) bias in a compound letter global/local (GL) task, supporting the claim of disrupted holistic processing in prosopagnosia. Here, we investigate further the nature of holistic processing impairments in CP, first by confirming, in a large sample of CP individuals, the absence of the normal face inversion effect and the presence of the local bias on the GL task, and, second, by employing the composite face paradigm, often regarded as the gold standard for measuring holistic face processing. In this last task, we show that, in contrast with normal individuals, the CP group perform equivalently with aligned and misaligned faces and was impervious to (the normal) interference from the task-irrelevant bottom part of faces. Interestingly, the extent of the local bias evident in the composite task is correlated with the abnormality of performance on diagnostic face processing tasks. Furthermore, there is a significant correlation between the magnitude of the local bias in the GL and performance on the composite task. These results provide further evidence for impaired holistic processing in CP and, moreover, corroborate the critical role of this type of processing for intact face recognition. PMID:21601583
From face processing to face recognition: Comparing three different processing levels.
Besson, G; Barragan-Jason, G; Thorpe, S J; Fabre-Thorpe, M; Puma, S; Ceccaldi, M; Barbeau, E J
2017-01-01
Verifying that a face is from a target person (e.g. finding someone in the crowd) is a critical ability of the human face processing system. Yet how fast this can be performed is unknown. The 'entry-level shift due to expertise' hypothesis suggests that - since humans are face experts - processing faces should be as fast - or even faster - at the individual than at superordinate levels. In contrast, the 'superordinate advantage' hypothesis suggests that faces are processed from coarse to fine, so that the opposite pattern should be observed. To clarify this debate, three different face processing levels were compared: (1) a superordinate face categorization level (i.e. detecting human faces among animal faces), (2) a face familiarity level (i.e. recognizing famous faces among unfamiliar ones) and (3) verifying that a face is from a target person, our condition of interest. The minimal speed at which faces can be categorized (∼260ms) or recognized as familiar (∼360ms) has largely been documented in previous studies, and thus provides boundaries to compare our condition of interest to. Twenty-seven participants were included. The recent Speed and Accuracy Boosting procedure paradigm (SAB) was used since it constrains participants to use their fastest strategy. Stimuli were presented either upright or inverted. Results revealed that verifying that a face is from a target person (minimal RT at ∼260ms) was remarkably fast but longer than the face categorization level (∼240ms) and was more sensitive to face inversion. In contrast, it was much faster than recognizing a face as familiar (∼380ms), a level severely affected by face inversion. Face recognition corresponding to finding a specific person in a crowd thus appears achievable in only a quarter of a second. In favor of the 'superordinate advantage' hypothesis or coarse-to-fine account of the face visual hierarchy, these results suggest a graded engagement of the face processing system across processing levels as reflected by the face inversion effects. Furthermore, they underline how verifying that a face is from a target person and detecting a face as familiar - both often referred to as "Face Recognition" - in fact differs. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Huhn, Stefan; Peeling, Derek; Burkart, Maximilian
2017-10-01
With the availability of die face design tools and incremental solver technologies to provide detailed forming feasibility results in a timely fashion, the use of inverse solver technologies and resulting process improvements during the product development process of stamped parts often is underestimated. This paper presents some applications of inverse technologies that are currently used in the automotive industry to streamline the product development process and greatly increase the quality of a developed process and the resulting product. The first focus is on the so-called target strain technology. Application examples will show how inverse forming analysis can be applied to support the process engineer during the development of a die face geometry for Class `A' panels. The drawing process is greatly affected by the die face design and the process designer has to ensure that the resulting drawn panel will meet specific requirements regarding surface quality and a minimum strain distribution to ensure dent resistance. The target strain technology provides almost immediate feedback to the process engineer during the die face design process if a specific change of the die face design will help to achieve these specific requirements or will be counterproductive. The paper will further show how an optimization of the material flow can be achieved through the use of a newly developed technology called Sculptured Die Face (SDF). The die face generation in SDF is more suited to be used in optimization loops than any other conventional die face design technology based on cross section design. A second focus in this paper is on the use of inverse solver technologies for secondary forming operations. The paper will show how the application of inverse technology can be used to accurately and quickly develop trim lines on simple as well as on complex support geometries.
Differences between perception of human faces and body shapes: evidence from the composite illusion.
Soria Bauser, Denise A; Suchan, Boris; Daum, Irene
2011-01-01
The present study aimed to investigate whether human body forms--like human faces--undergo holistic processing. Evidence for holistic face processing comes from the face composite effect: two identical top halves of a face are perceived as being different if they are presented with different bottom parts. This effect disappears if both bottom halves are shifted laterally (misaligned) or if the stimulus is rotated by 180°. We investigated whether comparable composite effects are observed for human faces and human body forms. Matching of upright faces was more accurate and faster for misaligned compared to aligned presentations. By contrast, there were no processing differences between aligned and misaligned bodies. An inversion effect emerged, with better recognition performance for upright compared to inverted bodies but not faces. The present findings provide evidence for the assumption that holistic processing--investigated with the composite illusion--is not involved in the perception of human body forms. Copyright © 2010 Elsevier Ltd. All rights reserved.
Perceptual expertise in forensic facial image comparison.
White, David; Phillips, P Jonathon; Hahn, Carina A; Hill, Matthew; O'Toole, Alice J
2015-09-07
Forensic facial identification examiners are required to match the identity of faces in images that vary substantially, owing to changes in viewing conditions and in a person's appearance. These identifications affect the course and outcome of criminal investigations and convictions. Despite calls for research on sources of human error in forensic examination, existing scientific knowledge of face matching accuracy is based, almost exclusively, on people without formal training. Here, we administered three challenging face matching tests to a group of forensic examiners with many years' experience of comparing face images for law enforcement and government agencies. Examiners outperformed untrained participants and computer algorithms, thereby providing the first evidence that these examiners are experts at this task. Notably, computationally fusing responses of multiple experts produced near-perfect performance. Results also revealed qualitative differences between expert and non-expert performance. First, examiners' superiority was greatest at longer exposure durations, suggestive of more entailed comparison in forensic examiners. Second, experts were less impaired by image inversion than non-expert students, contrasting with face memory studies that show larger face inversion effects in high performers. We conclude that expertise in matching identity across unfamiliar face images is supported by processes that differ qualitatively from those supporting memory for individual faces. © 2015 The Author(s).
NASA Astrophysics Data System (ADS)
Nicollin, Florence; Gibert, Dominique; Lesparre, Nolwenn; Nussbaum, Christophe
2010-04-01
Electrical resistivity measurements were performed to characterize the anisotropy of electrical resistivity of the excavation damaged zone (EDZ) at the end-face of a gallery in the Opalinus clay of the Mont Terri Underground Rock Laboratory (URL). The data were acquired with a combination of square arrays in 18 zones on the gallery's face and in two series of four boreholes perpendicular to the face. Each data set is independently inverted using simulated annealing to recover the resistivity tensor. Both the stability and the non-uniqueness of the inverse problem are discussed with synthetic examples. The inversion of the data shows that the face is split in two domains separated by a tectonic fracture, with different resistivity values but with a common orientation. The direction of the maximum resistivity is found perpendicular to the bedding plane, and the direction of minimum resistivity is contained in the face's plane. These results show that the geo-electrical structure of the EDZ is controlled by a combination of effects due to tectonics, stratigraphy, and recent fracturing produced by the excavation of the gallery.
Semisupervised kernel marginal Fisher analysis for face recognition.
Wang, Ziqiang; Sun, Xia; Sun, Lijun; Huang, Yuchun
2013-01-01
Dimensionality reduction is a key problem in face recognition due to the high-dimensionality of face image. To effectively cope with this problem, a novel dimensionality reduction algorithm called semisupervised kernel marginal Fisher analysis (SKMFA) for face recognition is proposed in this paper. SKMFA can make use of both labelled and unlabeled samples to learn the projection matrix for nonlinear dimensionality reduction. Meanwhile, it can successfully avoid the singularity problem by not calculating the matrix inverse. In addition, in order to make the nonlinear structure captured by the data-dependent kernel consistent with the intrinsic manifold structure, a manifold adaptive nonparameter kernel is incorporated into the learning process of SKMFA. Experimental results on three face image databases demonstrate the effectiveness of our proposed algorithm.
Fakra, Eric; Jouve, Elisabeth; Guillaume, Fabrice; Azorin, Jean-Michel; Blin, Olivier
2015-03-01
Deficit in facial affect recognition is a well-documented impairment in schizophrenia, closely connected to social outcome. This deficit could be related to psychopathology, but also to a broader dysfunction in processing facial information. In addition, patients with schizophrenia inadequately use configural information-a type of processing that relies on spatial relationships between facial features. To date, no study has specifically examined the link between symptoms and misuse of configural information in the deficit in facial affect recognition. Unmedicated schizophrenia patients (n = 30) and matched healthy controls (n = 30) performed a facial affect recognition task and a face inversion task, which tests aptitude to rely on configural information. In patients, regressions were carried out between facial affect recognition, symptom dimensions and inversion effect. Patients, compared with controls, showed a deficit in facial affect recognition and a lower inversion effect. Negative symptoms and lower inversion effect could account for 41.2% of the variance in facial affect recognition. This study confirms the presence of a deficit in facial affect recognition, and also of dysfunctional manipulation in configural information in antipsychotic-free patients. Negative symptoms and poor processing of configural information explained a substantial part of the deficient recognition of facial affect. We speculate that this deficit may be caused by several factors, among which independently stand psychopathology and failure in correctly manipulating configural information. PsycINFO Database Record (c) 2015 APA, all rights reserved.
Lorenzino, Martina; Caminati, Martina; Caudek, Corrado
2018-05-25
One of the most important questions in face perception research is to understand what information is extracted from a face in order to recognize its identity. Recognition of facial identity has been attributed to a special sensitivity to "configural" information. However, recent studies have challenged the configural account by showing that participants are poor in discriminating variations of metric distances among facial features, especially for familiar as opposed to unfamiliar faces, whereas a configural account predicts the opposite. We aimed to extend these previous results by examining classes of unfamiliar faces with which we have different levels of expertise. We hypothesized an inverse relation between sensitivity to configural information and expertise with a given class of faces, but only for neutral expressions. By first matching perceptual discriminability, we measured tolerance to subtle configural transformations with same-race (SR) versus other-race (OR) faces, and with upright versus upside-down faces. Consistently with our predictions, we found a lower sensitivity to at-threshold configural changes for SR compared to OR faces. We also found that, for our stimuli, the face inversion effect disappeared for neutral but not for emotional faces - a result that can also be attributed to a lower sensitivity to configural transformations for faces presented in a more familiar orientation. The present findings question a purely configural account of face processing and suggest that the role of spatial-relational information in face processing varies according to the functional demands of the task and to the characteristics of the stimuli. Copyright © 2018 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Vida, Mark D.; Maurer, Daphne; Calder, Andrew J.; Rhodes, Gillian; Walsh, Jennifer A.; Pachai, Matthew V.; Rutherford, M. D.
2013-01-01
We examined the influences of face inversion and facial expression on sensitivity to eye contact in high-functioning adults with and without an autism spectrum disorder (ASD). Participants judged the direction of gaze of angry, fearful, and neutral faces. In the typical group only, the range of directions of gaze leading to the perception of eye…
On Response Bias in the Face Congruency Effect for Internal and External Features
Meinhardt, Günter; Meinhardt-Injac, Bozana; Persike, Malte
2017-01-01
Some years ago Cheung et al. (2008) proposed the complete design (CD) for measuring the failure of selective attention in composite objects. Since the CD is a fully balanced design, analysis of response bias may reveal potential effects of the experimental manipulation, the stimulus material, and/or attributes of the observers. Here we used the CD to prove whether external features modulate perception of internal features with the context congruency paradigm (Nachson et al., 1995; Meinhardt-Injac et al., 2010) in a larger sample of N = 303 subjects. We found a large congruency effect (Cohen's d = 1.78), which was attenuated by face inversion (d = 1.32). The congruency relation also strongly modulated response bias. In incongruent trials the proportion of “different” responses was much larger than in congruent trials (d = 0.79), which was again attenuated by face inversion (d = 0.43). Because in incongruent trials the wholes formed by integrating external and internal features are always different, while in congruent trials same and different wholes occur with the same frequency, a congruency related bias effect is expected from holistic integration. Our results suggest two behavioral markers of holistic processing in the context congruency paradigm: a performance advantage in congruent compared to incongruent trials, and a tendency toward more “different” responses in incongruent, compared to congruent trials. Since the results for both markers differed only quantitatively in upright and inverted presentation, our findings indicate no change of the face processing mode by picture plane rotation. A potential transfer to the composite face paradigm is discussed. PMID:29089880
Karmiloff-Smith, Annette; Thomas, Michael; Annaz, Dagmara; Humphreys, Kate; Ewing, Sandra; Brace, Nicola; Duuren, Mike; Pike, Graham; Grice, Sarah; Campbell, Ruth
2004-10-01
Face processing in Williams syndrome (WS) has been a topic of heated debate over the past decade. Initial claims about a normally developing ('intact') face-processing module were challenged by data suggesting that individuals with WS used a different balance of cognitive processes from controls, even when their behavioural scores fell within the normal range. Measurement of evoked brain potentials also point to atypical processes. However, two recent studies have claimed that people with WS process faces exactly like normal controls. In this paper, we examine the details of this continuing debate on the basis of three new face-processing experiments. In particular, for two of our experiments we built task-specific full developmental trajectories from childhood to adolescence/adulthood and plotted the WS data on these trajectories. The first experiment used photos of real faces. While it revealed broadly equivalent accuracy across groups, the WS participants were worse at configural processing when faces were upright and less sensitive than controls to face inversion. In Experiment 2, measuring face processing in a storybook context, the face inversion effect emerged clearly in controls but only weakly in the WS developmental trajectory. Unlike the controls, the Benton Face Recognition Test and the Pattern Construction results were not correlated in WS, highlighting the different developmental patterns in the two groups. Again in contrast to the controls, Experiment 3 with schematic faces and non-face stimuli revealed a configural-processing deficit in WS both with respect to their chronological age (CA) and to their level of performance on the Benton. These findings point to both delay and deviance in WS face processing and illustrate how vital it is to build developmental trajectories for each specific task.
Integrating conventional and inverse representation for face recognition.
Xu, Yong; Li, Xuelong; Yang, Jian; Lai, Zhihui; Zhang, David
2014-10-01
Representation-based classification methods are all constructed on the basis of the conventional representation, which first expresses the test sample as a linear combination of the training samples and then exploits the deviation between the test sample and the expression result of every class to perform classification. However, this deviation does not always well reflect the difference between the test sample and each class. With this paper, we propose a novel representation-based classification method for face recognition. This method integrates conventional and the inverse representation-based classification for better recognizing the face. It first produces conventional representation of the test sample, i.e., uses a linear combination of the training samples to represent the test sample. Then it obtains the inverse representation, i.e., provides an approximation representation of each training sample of a subject by exploiting the test sample and training samples of the other subjects. Finally, the proposed method exploits the conventional and inverse representation to generate two kinds of scores of the test sample with respect to each class and combines them to recognize the face. The paper shows the theoretical foundation and rationale of the proposed method. Moreover, this paper for the first time shows that a basic nature of the human face, i.e., the symmetry of the face can be exploited to generate new training and test samples. As these new samples really reflect some possible appearance of the face, the use of them will enable us to obtain higher accuracy. The experiments show that the proposed conventional and inverse representation-based linear regression classification (CIRLRC), an improvement to linear regression classification (LRC), can obtain very high accuracy and greatly outperforms the naive LRC and other state-of-the-art conventional representation based face recognition methods. The accuracy of CIRLRC can be 10% greater than that of LRC.
Miki, Kensaku; Takeshima, Yasuyuki; Watanabe, Shoko; Honda, Yukiko; Kakigi, Ryusuke
2011-04-06
We investigated the effects of inverting facial contour (hair and chin) and features (eyes, nose and mouth) on processing for static and dynamic face perception using magnetoencephalography (MEG). We used apparent motion, in which the first stimulus (S1) was replaced by a second stimulus (S2) with no interstimulus interval and subjects perceived visual motion, and presented three conditions as follows: (1) U&U: Upright contour and Upright features, (2) U&I: Upright contour and Inverted features, and (3) I&I: Inverted contour and Inverted features. In static face perception (S1 onset), the peak latency of the fusiform area's activity, which was related to static face perception, was significantly longer for U&I and I&I than for U&U in the right hemisphere and for U&I than for U&U and I&I in the left. In dynamic face perception (S2 onset), the strength (moment) of the occipitotemporal area's activity, which was related to dynamic face perception, was significantly larger for I&I than for U&U and U&I in the right hemisphere, but not the left. These results can be summarized as follows: (1) in static face perception, the activity of the right fusiform area was more affected by the inversion of features while that of the left fusiform area was more affected by the disruption of the spatial relation between the contour and features, and (2) in dynamic face perception, the activity of the right occipitotemporal area was affected by the inversion of the facial contour. Copyright © 2011 Elsevier B.V. All rights reserved.
The Impact of Early Bilingualism on Face Recognition Processes.
Kandel, Sonia; Burfin, Sabine; Méary, David; Ruiz-Tada, Elisa; Costa, Albert; Pascalis, Olivier
2016-01-01
Early linguistic experience has an impact on the way we decode audiovisual speech in face-to-face communication. The present study examined whether differences in visual speech decoding could be linked to a broader difference in face processing. To identify a phoneme we have to do an analysis of the speaker's face to focus on the relevant cues for speech decoding (e.g., locating the mouth with respect to the eyes). Face recognition processes were investigated through two classic effects in face recognition studies: the Other-Race Effect (ORE) and the Inversion Effect. Bilingual and monolingual participants did a face recognition task with Caucasian faces (own race), Chinese faces (other race), and cars that were presented in an Upright or Inverted position. The results revealed that monolinguals exhibited the classic ORE. Bilinguals did not. Overall, bilinguals were slower than monolinguals. These results suggest that bilinguals' face processing abilities differ from monolinguals'. Early exposure to more than one language may lead to a perceptual organization that goes beyond language processing and could extend to face analysis. We hypothesize that these differences could be due to the fact that bilinguals focus on different parts of the face than monolinguals, making them more efficient in other race face processing but slower. However, more studies using eye-tracking techniques are necessary to confirm this explanation.
The Influence of Flankers on Race Categorization of Faces
Sun, Hsin-Mei; Balas, Benjamin
2012-01-01
Context affects multiple cognitive and perceptual processes. In the present study, we asked how the context of a set of faces affected the perception of a target face’s race in two distinct tasks. In Experiments 1 and 2, participants categorized target faces according to perceived racial category (Black or White). In Experiment 1, the target face was presented alone, or with Black or White flanker faces. The orientation of flanker faces was also manipulated to investigate how face inversion effect interacts with the influences of flanker faces on the target face. The results showed that participants were more likely to categorize the target face as White when it was surrounded by inverted White faces (an assimilation effect). Experiment 2 further examined how different aspects of the visual context affect the perception of the target face by manipulating flanker faces’ shape and pigmentation as well as their orientation. The results showed that flanker faces’ shape and pigmentation affected the perception of the target face differently. While shape elicited a contrast effect, pigmentation appeared to be assimilative. These novel findings suggest that the perceived race of a face is modulated by the appearance of other faces and their distinct shape and pigmentation properties. However, the contrast and assimilation effects elicited by flanker faces’ shape and pigmentation may be specific to race categorization, since the same stimuli used in a delayed matching task (Experiment 3) revealed that flanker pigmentation induced a contrast effect on the perception of target pigmentation. PMID:22825930
Neural and cognitive face-selective markers: An integrative review.
Yovel, Galit
2016-03-01
Faces elicit robust and selective neural responses in the primate brain. These neural responses have been investigated with functional MRI and EEG in numerous studies, which have reported face-selective activations in the occipital-temporal cortex and an electrophysiological face-selective response that peaks 170 ms after stimulus onset at occipital-temporal sites. Evidence for face-selective processes has also been consistently reported in cognitive studies, which investigated the face inversion effect, the composite face effect and the left visual field (LVF) superiority. These cognitive effects indicate that the perceptual representation that we generate for faces differs from the representation that is generated for inverted faces or non-face objects. In this review, I will show that the fMRI and ERP face-selective responses are strongly associated with these three well-established behavioral face-selective measures. I will further review studies that examined the relationship between fMRI and EEG face-selective measures suggesting that they are strongly linked. Taken together these studies imply that a holistic representation of a face is generated at 170 ms after stimulus onset over the right hemisphere. These findings, which reveal a strong link between the various and complementary cognitive and neural measures of face processing, allow to characterize where, when and how faces are represented during the first 200 ms of face processing. Copyright © 2015 Elsevier Ltd. All rights reserved.
Joint sparse learning for 3-D facial expression generation.
Song, Mingli; Tao, Dacheng; Sun, Shengpeng; Chen, Chun; Bu, Jiajun
2013-08-01
3-D facial expression generation, including synthesis and retargeting, has received intensive attentions in recent years, because it is important to produce realistic 3-D faces with specific expressions in modern film production and computer games. In this paper, we present joint sparse learning (JSL) to learn mapping functions and their respective inverses to model the relationship between the high-dimensional 3-D faces (of different expressions and identities) and their corresponding low-dimensional representations. Based on JSL, we can effectively and efficiently generate various expressions of a 3-D face by either synthesizing or retargeting. Furthermore, JSL is able to restore 3-D faces with holes by learning a mapping function between incomplete and intact data. Experimental results on a wide range of 3-D faces demonstrate the effectiveness of the proposed approach by comparing with representative ones in terms of quality, time cost, and robustness.
Corrow, Sherryse L; Mathison, Jordan; Granrud, Carl E; Yonas, Albert
2014-01-01
Corrow, Granrud, Mathison, and Yonas (2011, Perception, 40, 1376-1383) found evidence that 6-month-old infants perceive the hollow face illusion. In the present study we asked whether 6-month-old infants perceive illusory depth reversal for a nonface object and whether infants' perception of the hollow face illusion is affected by mask orientation inversion. In experiment 1 infants viewed a concave bowl, and their reaches were recorded under monocular and binocular viewing conditions. Infants reached to the bowl as if it were convex significantly more often in the monocular than in the binocular viewing condition. These results suggest that infants perceive illusory depth reversal with a nonface stimulus and that the infant visual system has a bias to perceive objects as convex. Infants in experiment 2 viewed a concave face-like mask in upright and inverted orientations. Infants reached to the display as if it were convex more in the monocular than in the binocular condition; however, mask orientation had no effect on reaching. Previous findings that adults' perception of the hollow face illusion is affected by mask orientation inversion have been interpreted as evidence of stored-knowledge influences on perception. However, we found no evidence of such influences in infants, suggesting that their perception of this illusion may not be affected by stored knowledge, and that perceived depth reversal is not face-specific in infants.
Behavioral and neural evidence of increased attention to the bottom half of the face in deaf signers
Mitchell, Teresa V.; Letourneau, Susan M.; Maslin, Melissa T.
2013-01-01
Purpose This study examined the effects of deafness and sign language use on the distribution of attention across the top and bottom halves of faces. Methods In a composite face task, congenitally deaf signers and typically hearing controls made same/different judgments of the top or bottom halves of faces presented with the halves aligned or spatially misaligned, while event-related potentials (ERPs) were recorded. Results Both groups were more accurate when judging misaligned than aligned faces, which indicates holistic face processing. Misalignment affected all ERP components examined, with effects on the N170 resembling those of face inversion. Hearing adults were similarly accurate when judging the top and bottom halves of the faces, but deaf signers were more accurate when attending to the bottom than the top. Attending to the top elicited faster P1 and N170 latencies for both groups; within the deaf group, this effect was greatest for individuals who produced the highest accuracies when attending to the top. Conclusions These findings dovetail with previous research by providing behavioral and neural evidence of increased attention to the bottom half of the face in deaf signers, and by documenting that these effects generalize to a speeded task, in the absence of gaze shifts, with neutral facial expressions. PMID:23142816
Mitchell, Teresa V; Letourneau, Susan M; Maslin, Melissa C T
2013-01-01
This study examined the effects of deafness and sign language use on the distribution of attention across the top and bottom halves of faces. In a composite face task, congenitally deaf signers and typically hearing controls made same/different judgments of the top or bottom halves of faces presented with the halves aligned or spatially misaligned, while event-related potentials (ERPs) were recorded. Both groups were more accurate when judging misaligned than aligned faces, which indicates holistic face processing. Misalignment affected all ERP components examined, with effects on the N170 resembling those of face inversion. Hearing adults were similarly accurate when judging the top and bottom halves of the faces, but deaf signers were more accurate when attending to the bottom than the top. Attending to the top elicited faster P1 and N170 latencies for both groups; within the deaf group, this effect was greatest for individuals who produced the highest accuracies when attending to the top. These findings dovetail with previous research by providing behavioral and neural evidence of increased attention to the bottom half of the face in deaf signers, and by documenting that these effects generalize to a speeded task, in the absence of gaze shifts, with neutral facial expressions.
Nihei, Yuji; Minami, Tetsuto; Nakauchi, Shigeki
2018-01-01
Faces represent important information for social communication, because social information, such as face-color, expression, and gender, is obtained from faces. Therefore, individuals' tend to find faces unconsciously, even in objects. Why is face-likeness perceived in non-face objects? Previous event-related potential (ERP) studies showed that the P1 component (early visual processing), the N170 component (face detection), and the N250 component (personal detection) reflect the neural processing of faces. Inverted faces were reported to enhance the amplitude and delay the latency of P1 and N170. To investigate face-likeness processing in the brain, we explored the face-related components of the ERP through a face-like evaluation task using natural faces, cars, insects, and Arcimboldo paintings presented upright or inverted. We found a significant correlation between the inversion effect index and face-like scores in P1 in both hemispheres and in N170 in the right hemisphere. These results suggest that judgment of face-likeness occurs in a relatively early stage of face processing.
Nihei, Yuji; Minami, Tetsuto; Nakauchi, Shigeki
2018-01-01
Faces represent important information for social communication, because social information, such as face-color, expression, and gender, is obtained from faces. Therefore, individuals' tend to find faces unconsciously, even in objects. Why is face-likeness perceived in non-face objects? Previous event-related potential (ERP) studies showed that the P1 component (early visual processing), the N170 component (face detection), and the N250 component (personal detection) reflect the neural processing of faces. Inverted faces were reported to enhance the amplitude and delay the latency of P1 and N170. To investigate face-likeness processing in the brain, we explored the face-related components of the ERP through a face-like evaluation task using natural faces, cars, insects, and Arcimboldo paintings presented upright or inverted. We found a significant correlation between the inversion effect index and face-like scores in P1 in both hemispheres and in N170 in the right hemisphere. These results suggest that judgment of face-likeness occurs in a relatively early stage of face processing. PMID:29503612
Croydon, Abigail; Pimperton, Hannah; Ewing, Louise; Duchaine, Brad C; Pellicano, Elizabeth
2014-09-01
Face recognition ability follows a lengthy developmental course, not reaching maturity until well into adulthood. Valid and reliable assessments of face recognition memory ability are necessary to examine patterns of ability and disability in face processing, yet there is a dearth of such assessments for children. We modified a well-known test of face memory in adults, the Cambridge Face Memory Test (Duchaine & Nakayama, 2006, Neuropsychologia, 44, 576-585), to make it developmentally appropriate for children. To establish its utility, we administered either the upright or inverted versions of the computerised Cambridge Face Memory Test - Children (CFMT-C) to 401 children aged between 5 and 12 years. Our results show that the CFMT-C is sufficiently sensitive to demonstrate age-related gains in the recognition of unfamiliar upright and inverted faces, does not suffer from ceiling or floor effects, generates robust inversion effects, and is capable of detecting difficulties in face memory in children diagnosed with autism. Together, these findings indicate that the CFMT-C constitutes a new valid assessment tool for children's face recognition skills. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Bin, Liu; Zhengyu, Liu; Shucai, Li; Lichao, Nie; Maoxin, Su; Huaifeng, Sun; Kerui, Fan; Xinxin, Zhang; Yonghao, Pang
2017-09-01
This paper describes the application of a comprehensive surface geophysical investigation of underground karst systems ahead of the tunnel face in the Xiaoheyan section in the main line of the water supply project from Songhua River, located in Jilin, China. To make an accurate investigation, Surface Electrical Resistivity Tomography (S-ERT), Transient Electromagnetic Method (TEM), Geological Drilling (Geo-D) and Three-dimensional Cross-hole Electrical Resistivity Tomography (3D cross-hole ERT) were applied to gain a comprehensive interpretation. To begin with, S-ERT and TEM are adopted to detect and delineate the underground karst zone. Based on the detection results, surface and in-tunnel Geo-D are placed in major areas with more specific and accurate information gained. After that, survey lines of 3D cross-hole ERT are used to conduct detailed exploration towards underground karst system. In the comprehensive investigation, it is the major question to make the best of prior information so as to promote the quality of detection. The paper has put forward strategies to make the full use of effective information in data processing and the main ideas of those strategies include: (1) Take the resistivity distribution of the subsurface stratum gained by S-ERT inversion as the initial model of TEM inversion; (2) Arrange borehole positions with the results of S-ERT and TEM. After that, gain more accurate information about resistivity of subsurface stratum using those boreholes located; (3) Through the comprehensive analysis of the information about S-ERT, TEM and Geo-D, set the initial model of 3D cross-hole resistivity inversion and meanwhile, gain the variation range of stratum resistivity. At last, a 3D cross-hole resistivity inversion based on the incorporated initial model and inequality constraint is conducted. Constrained inversion and joint interpretation are realized by the effective use of prior information in comprehensive investigation, helping to suppress the non-uniqueness problem of inversion so as to raise its reliability. In this way, a 3D detailed model of underground karst system which is 30 m ahead of tunnel face is finally formed. At the end of the paper, there is a geological sketch of the revealed karst caves, which illustrates the effectiveness of the presented strategy. To sum up, in the comprehensive investigation of underground karst caves, the integrated use of prior information can help to yield more accurate and detailed results.
Oliver, Lindsay D; Mao, Alexander; Mitchell, Derek G V
2015-01-01
Though emotional faces preferentially reach awareness, the present study utilised both objective and subjective indices of awareness to determine whether they enhance subjective awareness and "blindsight". Under continuous flash suppression, participants localised a disgusted, fearful or neutral face (objective index), and rated their confidence (subjective index). Psychopathic traits were also measured to investigate their influence on emotion perception. As predicted, fear increased localisation accuracy, subjective awareness and "blindsight" of upright faces. Coldhearted traits were inversely related to subjective awareness, but not "blindsight", of upright fearful faces. In a follow-up experiment using inverted faces, increased localisation accuracy and awareness, but not "blindsight", were observed for fear. Surprisingly, awareness of inverted fearful faces was positively correlated with coldheartedness. These results suggest that emotion enhances both pre-conscious processing and the qualitative experience of awareness, but that pre-conscious and conscious processing of emotional faces rely on at least partially dissociable cognitive mechanisms.
Super-Memorizers Are Not Super-Recognizers
Ramon, Meike; Miellet, Sebastien; Dzieciol, Anna M.; Konrad, Boris Nikolai
2016-01-01
Humans have a natural expertise in recognizing faces. However, the nature of the interaction between this critical visual biological skill and memory is yet unclear. Here, we had the unique opportunity to test two individuals who have had exceptional success in the World Memory Championships, including several world records in face-name association memory. We designed a range of face processing tasks to determine whether superior/expert face memory skills are associated with distinctive perceptual strategies for processing faces. Superior memorizers excelled at tasks involving associative face-name learning. Nevertheless, they were as impaired as controls in tasks probing the efficiency of the face system: face inversion and the other-race effect. Super memorizers did not show increased hippocampal volumes, and exhibited optimal generic eye movement strategies when they performed complex multi-item face-name associations. Our data show that the visual computations of the face system are not malleable and are robust to acquired expertise involving extensive training of associative memory. PMID:27008627
Super-Memorizers Are Not Super-Recognizers.
Ramon, Meike; Miellet, Sebastien; Dzieciol, Anna M; Konrad, Boris Nikolai; Dresler, Martin; Caldara, Roberto
2016-01-01
Humans have a natural expertise in recognizing faces. However, the nature of the interaction between this critical visual biological skill and memory is yet unclear. Here, we had the unique opportunity to test two individuals who have had exceptional success in the World Memory Championships, including several world records in face-name association memory. We designed a range of face processing tasks to determine whether superior/expert face memory skills are associated with distinctive perceptual strategies for processing faces. Superior memorizers excelled at tasks involving associative face-name learning. Nevertheless, they were as impaired as controls in tasks probing the efficiency of the face system: face inversion and the other-race effect. Super memorizers did not show increased hippocampal volumes, and exhibited optimal generic eye movement strategies when they performed complex multi-item face-name associations. Our data show that the visual computations of the face system are not malleable and are robust to acquired expertise involving extensive training of associative memory.
Bennetts, Rachel J; Mole, Joseph; Bate, Sarah
2017-09-01
Face recognition abilities vary widely. While face recognition deficits have been reported in children, it is unclear whether superior face recognition skills can be encountered during development. This paper presents O.B., a 14-year-old female with extraordinary face recognition skills: a "super-recognizer" (SR). O.B. demonstrated exceptional face-processing skills across multiple tasks, with a level of performance that is comparable to adult SRs. Her superior abilities appear to be specific to face identity: She showed an exaggerated face inversion effect and her superior abilities did not extend to object processing or non-identity aspects of face recognition. Finally, an eye-movement task demonstrated that O.B. spent more time than controls examining the nose - a pattern previously reported in adult SRs. O.B. is therefore particularly skilled at extracting and using identity-specific facial cues, indicating that face and object recognition are dissociable during development, and that super recognition can be detected in adolescence.
Duncum, A J F; Atkins, K J; Beilharz, F L; Mundy, M E
2016-01-01
Individuals with body dysmorphic disorder (BDD) and clinically concerning body-image concern (BIC) appear to possess abnormalities in the way they perceive visual information in the form of a bias towards local visual processing. As inversion interrupts normal global processing, forcing individuals to process locally, an upright-inverted stimulus discrimination task was used to investigate this phenomenon. We examined whether individuals with nonclinical, yet high levels of BIC would show signs of this bias, in the form of reduced inversion effects (i.e., increased local processing). Furthermore, we assessed whether this bias appeared for general visual stimuli or specifically for appearance-related stimuli, such as faces and bodies. Participants with high-BIC (n = 25) and low-BIC (n = 30) performed a stimulus discrimination task with upright and inverted faces, scenes, objects, and bodies. Unexpectedly, the high-BIC group showed an increased inversion effect compared to the low-BIC group, indicating perceptual abnormalities may not be present as local processing biases, as originally thought. There was no significant difference in performance across stimulus types, signifying that any visual processing abnormalities may be general rather than appearance-based. This has important implications for whether visual processing abnormalities are predisposing factors for BDD or develop throughout the disorder.
2015-12-15
UXO community . NAME Total Number: PERCENT_SUPPORTEDNAME FTE Equivalent: Total Number: Irma Shamatava 0.50 0.50 1 Resolving and Discriminating...Distinguishing an object of interest from innocuous items is the main problem that the UXO community is facing currently. This inverse problem...innocuous items is the main problem that the UXO community is facing currently. This inverse problem demands fast and accurate representation of
Face identity recognition in autism spectrum disorders: a review of behavioral studies.
Weigelt, Sarah; Koldewyn, Kami; Kanwisher, Nancy
2012-03-01
Face recognition--the ability to recognize a person from their facial appearance--is essential for normal social interaction. Face recognition deficits have been implicated in the most common disorder of social interaction: autism. Here we ask: is face identity recognition in fact impaired in people with autism? Reviewing behavioral studies we find no strong evidence for a qualitative difference in how facial identity is processed between those with and without autism: markers of typical face identity recognition, such as the face inversion effect, seem to be present in people with autism. However, quantitatively--i.e., how well facial identity is remembered or discriminated--people with autism perform worse than typical individuals. This impairment is particularly clear in face memory and in face perception tasks in which a delay intervenes between sample and test, and less so in tasks with no memory demand. Although some evidence suggests that this deficit may be specific to faces, further evidence on this question is necessary. Copyright © 2011 Elsevier Ltd. All rights reserved.
Chromosomal inversion differences correlate with range overlap in passerine birds.
Hooper, Daniel M; Price, Trevor D
2017-10-01
Chromosomal inversions evolve frequently but the reasons for this remain unclear. We used cytological descriptions of 411 species of passerine birds to identify large pericentric inversion differences between species, based on the position of the centromere. Within 81 small clades comprising 284 of the species, we found 319 differences on the 9 largest autosomes combined, 56 on the Z chromosome, and 55 on the W chromosome. We also identified inversions present within 32 species. Using a new fossil-calibrated phylogeny, we examined the phylogenetic, demographic and genomic context in which these inversions have evolved. The number of inversion differences between closely related species is consistently predicted by whether the ranges of species overlap, even when time is controlled for as far as is possible. Fixation rates vary across the autosomes, but inversions are more likely to be fixed on the Z chromosome than the average autosome. Variable mutagenic input alone (estimated by chromosome size, map length, GC content or repeat density) cannot explain the differences between chromosomes in the number of inversions fixed. Together, these results support a model in which inversions increase because of their effects on recombination suppression in the face of hybridization. Other factors associated with hybridization may also contribute, including the possibility that inversions contain incompatibility alleles, making taxa less likely to collapse following secondary contact.
Artificial faces are harder to remember
Balas, Benjamin; Pacella, Jonathan
2015-01-01
Observers interact with artificial faces in a range of different settings and in many cases must remember and identify computer-generated faces. In general, however, most adults have heavily biased experience favoring real faces over synthetic faces. It is well known that face recognition abilities are affected by experience such that faces belonging to “out-groups” defined by race or age are more poorly remembered and harder to discriminate from one another than faces belonging to the “in-group.” Here, we examine the extent to which artificial faces form an “out-group” in this sense when other perceptual categories are matched. We rendered synthetic faces using photographs of real human faces and compared performance in a memory task and a discrimination task across real and artificial versions of the same faces. We found that real faces were easier to remember, but only slightly more discriminable than artificial faces. Artificial faces were also equally susceptible to the well-known face inversion effect, suggesting that while these patterns are still processed by the human visual system in a face-like manner, artificial appearance does compromise the efficiency of face processing. PMID:26195852
Inverting faces elicits sensitivity to race on the N170 component: a cross-cultural study.
Vizioli, Luca; Foreman, Kay; Rousselet, Guillaume A; Caldara, Roberto
2010-01-29
Human beings are natural experts at processing faces, with some notable exceptions. Same-race faces are better recognized than other-race faces: the so-called other-race effect (ORE). Inverting faces impairs recognition more than for any other inverted visual object: the so-called face inversion effect (FIE). Interestingly, the FIE is stronger for same- compared to other-race faces. At the electrophysiological level, inverted faces elicit consistently delayed and often larger N170 compared to upright faces. However, whether the N170 component is sensitive to race is still a matter of ongoing debate. Here we investigated the N170 sensitivity to race in the framework of the FIE. We recorded EEG from Western Caucasian and East Asian observers while presented with Western Caucasian, East Asian and African American faces in upright and inverted orientations. To control for potential confounds in the EEG signal that might be evoked by the intrinsic and salient differences in the low-level properties of faces from different races, we normalized their amplitude-spectra, luminance and contrast. No differences on the N170 were observed for upright faces. Critically, inverted same-race faces lead to greater recognition impairment and elicited larger N170 amplitudes compared to inverted other-race faces. Our results indicate a finer-grained neural tuning for same-race faces at early stages of processing in both groups of observers.
An inverse dynamics approach to face animation.
Pitermann, M; Munhall, K G
2001-09-01
Muscle-based models of the human face produce high quality animation but rely on recorded muscle activity signals or synthetic muscle signals that are often derived by trial and error. This paper presents a dynamic inversion of a muscle-based model (Lucero and Munhall, 1999) that permits the animation to be created from kinematic recordings of facial movements. Using a nonlinear optimizer (Powell's algorithm), the inversion produces a muscle activity set for seven muscles in the lower face that minimize the root mean square error between kinematic data recorded with OPTOTRAK and the corresponding nodes of the modeled facial mesh. This inverted muscle activity is then used to animate the facial model. In three tests of the inversion, strong correlations were observed for kinematics produced from synthetic muscle activity, for OPTOTRAK kinematics recorded from a talker for whom the facial model is morphologically adapted and finally for another talker with the model morphology adapted to a different individual. The correspondence between the animation kinematics and the three-dimensional OPTOTRAK data are very good and the animation is of high quality. Because the kinematic to electromyography (EMG) inversion is ill posed, there is no relation between the actual EMG and the inverted EMG. The overall redundancy of the motor system means that many different EMG patterns can produce the same kinematic output.
Relation between Amygdala Structure and Function in Adolescents with Bipolar Disorder
ERIC Educational Resources Information Center
Kalmar, Jessica H.; Wang, Fei; Chepenik, Lara G.; Womer, Fay Y.; Jones, Monique M.; Pittman, Brian; Shah, Maulik P.; Martin, Andres; Constable, R. Todd; Blumberg, Hilary P.
2009-01-01
Adolescents with bipolar disorder showed decreased amygdala volume and increased amygdala response to emotional faces. Amygdala volume is inversely related to activation during emotional face processing.
Monkeys and Humans Share a Common Computation for Face/Voice Integration
Chandrasekaran, Chandramouli; Lemus, Luis; Trubanova, Andrea; Gondan, Matthias; Ghazanfar, Asif A.
2011-01-01
Speech production involves the movement of the mouth and other regions of the face resulting in visual motion cues. These visual cues enhance intelligibility and detection of auditory speech. As such, face-to-face speech is fundamentally a multisensory phenomenon. If speech is fundamentally multisensory, it should be reflected in the evolution of vocal communication: similar behavioral effects should be observed in other primates. Old World monkeys share with humans vocal production biomechanics and communicate face-to-face with vocalizations. It is unknown, however, if they, too, combine faces and voices to enhance their perception of vocalizations. We show that they do: monkeys combine faces and voices in noisy environments to enhance their detection of vocalizations. Their behavior parallels that of humans performing an identical task. We explored what common computational mechanism(s) could explain the pattern of results we observed across species. Standard explanations or models such as the principle of inverse effectiveness and a “race” model failed to account for their behavior patterns. Conversely, a “superposition model”, positing the linear summation of activity patterns in response to visual and auditory components of vocalizations, served as a straightforward but powerful explanatory mechanism for the observed behaviors in both species. As such, it represents a putative homologous mechanism for integrating faces and voices across primates. PMID:21998576
Steepening of Waves at the Duskside Magnetopause
NASA Technical Reports Server (NTRS)
Plaschke, F.; Kahr, N.; Fischer, D.; Nakamura, R.; Baumjohann, W.; Magnes, W.; Burch, J. L.; Torbert, R.; Russell, C. T.; Giles, B. L.;
2016-01-01
Surface waves at the magnetopause flanks typically feature steeper, i.e., more inclined leading (antisunward facing) than trailing (sunward facing) edges. This is expected for Kelvin-Helmholtz instability (KHI) amplified waves. Very rarely, during northward interplanetary magnetic field (IMF) conditions, anomalous inverse steepening has been observed. The small-scale tetrahedral configuration of the Magnetospheric Multiscale spacecraft and their high time resolution measurements enable us to routinely ascertain magnetopause boundary inclinations during surface wave passage with high accuracy by four-spacecraft timing analysis. At the dusk flank magnetopause, 77%/23% of the analyzed wave intervals exhibit regular inverse steepening. Inverse steepening happens during northward IMF conditions, as previously reported and, in addition, during intervals of dominant equatorial IMF. Inverse steepening observed under the latter conditions may be due to the absence of KHI or due to instabilities arising from the alignment of flow and magnetic fields in the magnetosheath.
Familiarity enhances visual working memory for faces.
Jackson, Margaret C; Raymond, Jane E
2008-06-01
Although it is intuitive that familiarity with complex visual objects should aid their preservation in visual working memory (WM), empirical evidence for this is lacking. This study used a conventional change-detection procedure to assess visual WM for unfamiliar and famous faces in healthy adults. Across experiments, faces were upright or inverted and a low- or high-load concurrent verbal WM task was administered to suppress contribution from verbal WM. Even with a high verbal memory load, visual WM performance was significantly better and capacity estimated as significantly greater for famous versus unfamiliar faces. Face inversion abolished this effect. Thus, neither strategic, explicit support from verbal WM nor low-level feature processing easily accounts for the observed benefit of high familiarity for visual WM. These results demonstrate that storage of items in visual WM can be enhanced if robust visual representations of them already exist in long-term memory.
Deep and shallow encoding effects on face recognition: an ERP study.
Marzi, Tessa; Viggiano, Maria Pia
2010-12-01
Event related potentials (ERPs) were employed to investigate whether and when brain activity related to face recognition varies according to the processing level undertaken at encoding. Recognition was assessed when preceded by a "shallow" (orientation judgement) or by a "deep" study task (occupation judgement). Moreover, we included a further manipulation by presenting at encoding faces either in the upright or inverted orientation. As expected, deeply encoded faces were recognized more accurately and more quickly with respect to shallowly encoded faces. The ERP showed three main findings: i) as witnessed by more positive-going potentials for deeply encoded faces, at early and later processing stage, face recognition was influenced by the processing strategy adopted during encoding; ii) structural encoding, indexed by the N170, turned out to be "cognitively penetrable" showing repetition priming effects for deeply encoded faces; iii) face inversion, by disrupting configural processing during encoding, influenced memory related processes for deeply encoded faces and impaired the recognition of faces shallowly processed. The present study adds weight to the concept that the depth of processing during memory encoding affects retrieval. We found that successful retrieval following deep encoding involved both familiarity- and recollection-related processes showing from 500 ms a fronto-parietal distribution, whereas shallow encoding affected only earlier processing stages reflecting perceptual priming. Copyright © 2010 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Roberson, Debi; Kikutani, Mariko; Doge, Paula; Whitaker, Lydia; Majid, Asifa
2012-01-01
Three studies investigated developmental changes in facial expression processing, between 3 years-of-age and adulthood. For adults and older children, the addition of sunglasses to upright faces caused an equivalent decrement in performance to face inversion. However, younger children showed "better" classification of expressions of faces wearing…
Holistic processing and reliance on global viewing strategies in older adults' face perception.
Meinhardt-Injac, Bozana; Persike, Malte; Meinhardt, Günter
2014-09-01
There is increasing evidence that face recognition might be impaired in older adults, but it is unclear whether the impairment is truly perceptual, and face specific. In order to address this question we compared performance in same/different matching tasks with face and non-face objects (watches) among young (mean age 23.7) and older adults (mean age 70.4) using a context congruency paradigm (Meinhardt-Injac, Persike & Meinhardt, 2010, Meinhardt-Injac, Persike and Meinhardt, 2011a). Older adults were less accurate than young adults with both object classes, while face matching was notably impaired. Effects of context congruency and inversion, measured as the hallmarks of holistic processing, were equally strong in both age groups, and were found only for faces, but not for watches. The face specific decline in older adults revealed deficits in handling internal facial features, while young adults matched external and internal features equally well. Comparison with non-face stimuli showed that this decline was face specific, and did not concern processing of object features in general. Taken together, the results indicate no age-related decline in the capabilities to process faces holistically. Rather, strong holistic effects, combined with a loss of precision in handling internal features indicate that older adults rely on global viewing strategies for faces. At the same time, access to the exact properties of inner face details becomes restricted. Copyright © 2014. Published by Elsevier B.V.
McKone, Elinor; Hall, Ashleigh; Pidcock, Madeleine; Palermo, Romina; Wilkinson, Ross B; Rivolta, Davide; Yovel, Galit; Davis, Joshua M; O'Connor, Kirsty B
2011-03-01
The Cambridge Face Memory Test (CFMT, Duchaine & Nakayama, 2006) provides a validated format for testing novel face learning and has been a crucial instrument in the diagnosis of developmental prosopagnosia. Yet, some individuals who report everyday face recognition symptoms consistent with prosopagnosia, and are impaired on famous face tasks, perform normally on the CFMT. Possible reasons include measurement error, CFMT assessment of memory only at short delays, and a face set whose ethnicity is matched to only some Caucasian groups. We develop the "CFMT-Australian" (CFMT-Aus), which complements the CFMT-original by using ethnicity better matched to a different European subpopulation. Results confirm reliability (.88) and validity (convergent, divergent using cars, inversion effects). We show that face ethnicity within a race has subtle but clear effects on face processing even in normal participants (includes cross-over interaction for face ethnicity by perceiver country of origin in distinctiveness ratings). We show that CFMT-Aus clarifies diagnosis of prosopagnosia in 6 previously ambiguous cases. In 3 cases, this appears due to the better ethnic match to prosopagnosics. We also show that face memory at short (<3-min), 20-min, and 24-hr delays taps overlapping processes in normal participants. There is some suggestion that a form of prosopagnosia may exist that is long delay only and/or reflects failure to benefit from face repetition. © 2011 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business
Efficient search for a face by chimpanzees (Pan troglodytes).
Tomonaga, Masaki; Imura, Tomoko
2015-07-16
The face is quite an important stimulus category for human and nonhuman primates in their social lives. Recent advances in comparative-cognitive research clearly indicate that chimpanzees and humans process faces in a special manner; that is, using holistic or configural processing. Both species exhibit the face-inversion effect in which the inverted presentation of a face deteriorates their perception and recognition. Furthermore, recent studies have shown that humans detect human faces among non-facial objects rapidly. We report that chimpanzees detected chimpanzee faces among non-facial objects quite efficiently. This efficient search was not limited to own-species faces. They also found human adult and baby faces--but not monkey faces--efficiently. Additional testing showed that a front-view face was more readily detected than a profile, suggesting the important role of eye-to-eye contact. Chimpanzees also detected a photograph of a banana as efficiently as a face, but a further examination clearly indicated that the banana was detected mainly due to a low-level feature (i.e., color). Efficient face detection was hampered by an inverted presentation, suggesting that configural processing of faces is a critical element of efficient face detection in both species. This conclusion was supported by a simple simulation experiment using the saliency model.
Efficient search for a face by chimpanzees (Pan troglodytes)
Tomonaga, Masaki; Imura, Tomoko
2015-01-01
The face is quite an important stimulus category for human and nonhuman primates in their social lives. Recent advances in comparative-cognitive research clearly indicate that chimpanzees and humans process faces in a special manner; that is, using holistic or configural processing. Both species exhibit the face-inversion effect in which the inverted presentation of a face deteriorates their perception and recognition. Furthermore, recent studies have shown that humans detect human faces among non-facial objects rapidly. We report that chimpanzees detected chimpanzee faces among non-facial objects quite efficiently. This efficient search was not limited to own-species faces. They also found human adult and baby faces-but not monkey faces-efficiently. Additional testing showed that a front-view face was more readily detected than a profile, suggesting the important role of eye-to-eye contact. Chimpanzees also detected a photograph of a banana as efficiently as a face, but a further examination clearly indicated that the banana was detected mainly due to a low-level feature (i.e., color). Efficient face detection was hampered by an inverted presentation, suggesting that configural processing of faces is a critical element of efficient face detection in both species. This conclusion was supported by a simple simulation experiment using the saliency model. PMID:26180944
Utterance independent bimodal emotion recognition in spontaneous communication
NASA Astrophysics Data System (ADS)
Tao, Jianhua; Pan, Shifeng; Yang, Minghao; Li, Ya; Mu, Kaihui; Che, Jianfeng
2011-12-01
Emotion expressions sometimes are mixed with the utterance expression in spontaneous face-to-face communication, which makes difficulties for emotion recognition. This article introduces the methods of reducing the utterance influences in visual parameters for the audio-visual-based emotion recognition. The audio and visual channels are first combined under a Multistream Hidden Markov Model (MHMM). Then, the utterance reduction is finished by finding the residual between the real visual parameters and the outputs of the utterance related visual parameters. This article introduces the Fused Hidden Markov Model Inversion method which is trained in the neutral expressed audio-visual corpus to solve the problem. To reduce the computing complexity the inversion model is further simplified to a Gaussian Mixture Model (GMM) mapping. Compared with traditional bimodal emotion recognition methods (e.g., SVM, CART, Boosting), the utterance reduction method can give better results of emotion recognition. The experiments also show the effectiveness of our emotion recognition system when it was used in a live environment.
Devue, Christel; Barsics, Catherine
2016-10-01
Most humans seem to demonstrate astonishingly high levels of skill in face processing if one considers the sophisticated level of fine-tuned discrimination that face recognition requires. However, numerous studies now indicate that the ability to process faces is not as fundamental as once thought and that performance can range from despairingly poor to extraordinarily high across people. Here we studied people who are super specialists of faces, namely portrait artists, to examine how their specific visual experience with faces relates to a range of face processing skills (perceptual discrimination, short- and longer term recognition). Artists show better perceptual discrimination and, to some extent, recognition of newly learned faces than controls. They are also more accurate on other perceptual tasks (i.e., involving non-face stimuli or mental rotation). By contrast, artists do not display an advantage compared to controls on longer term face recognition (i.e., famous faces) nor on person recognition from other sensorial modalities (i.e., voices). Finally, the face inversion effect exists in artists and controls and is not modulated by artistic practice. Advantages in face processing for artists thus seem to closely mirror perceptual and visual short term memory skills involved in portraiture. Copyright © 2016 Elsevier Ltd. All rights reserved.
AUTISTIC TRAITS INFLUENCE GAZE-ORIENTED ATTENTION TO HAPPY BUT NOT FEARFUL FACES
Lassalle, Amandine; Itier, Roxane J.
2017-01-01
The relationship between autistic traits and gaze-oriented attention to fearful and happy faces was investigated at the behavioral and neuronal levels. Upright and inverted dynamic face stimuli were used in a gaze-cueing paradigm while ERPs were recorded. Participants responded faster to gazed-at than to non-gazed-at targets and this Gaze Orienting Effect (GOE) diminished with inversion, suggesting it relies on facial configuration. It was also larger for fearful than happy faces but only in participants with high Autism Quotient (AQ) scores. While the GOE to fearful faces was of similar magnitude regardless of AQ scores, a diminished GOE to happy faces was found in participants with high AQ scores. At the ERP level, a congruency effect on target-elicited P1 component reflected enhanced visual processing of gazed-at targets. In addition, cue-triggered early directing attention negativity and anterior directing attention negativity reflected, respectively, attention orienting and attention holding at gazed-at locations. These neural markers of spatial attention orienting were not modulated by emotion and were not found in participants with high AQ scores. Together these findings suggest that autistic traits influence attention orienting to gaze and its modulation by social emotions such as happiness. PMID:25222883
Yang, Ping; Wang, Min; Jin, Zhenlan; Li, Ling
2015-01-01
The ability to focus on task-relevant information, while suppressing distraction, is critical for human cognition and behavior. Using a delayed-match-to-sample (DMS) task, we investigated the effects of emotional face distractors (positive, negative, and neutral faces) on early and late phases of visual short-term memory (VSTM) maintenance intervals, using low and high VSTM loads. Behavioral results showed decreased accuracy and delayed reaction times (RTs) for high vs. low VSTM load. Event-related potentials (ERPs) showed enhanced frontal N1 and occipital P1 amplitudes for negative faces vs. neutral or positive faces, implying rapid attentional alerting effects and early perceptual processing of negative distractors. However, high VSTM load appeared to inhibit face processing in general, showing decreased N1 amplitudes and delayed P1 latencies. An inverse correlation between the N1 activation difference (high-load minus low-load) and RT costs (high-load minus low-load) was found at left frontal areas when viewing negative distractors, suggesting that the greater the inhibition the lower the RT cost for negative faces. Emotional interference effect was not found in the late VSTM-related parietal P300, frontal positive slow wave (PSW) and occipital negative slow wave (NSW) components. In general, our findings suggest that the VSTM load modulates the early attention and perception of emotional distractors. PMID:26388763
Simons, Raluca M; Simons, Jeffrey S; Olson, Dawne; Baugh, Lee; Magnotta, Vincent; Forster, Gina
2016-11-01
This fMRI study tested a model of combat trauma, posttraumatic stress symptoms (PTSS), alcohol use, and behavioral and neural responses to emotional cues in 100 OIF/OEF/OND veterans. Multilevel structural equation models were tested for left and right dorsal ACC (dACC), rostral ACC (rACC), and amygdala blood-oxygen- level dependent responses during the emotional counting Stroop test and masked faces task. In the Stroop task, combat exposure moderated the effect of combat stimuli resulting in hyperactivation in the rACC and dACC. Activation in the left amygdala also increased in response to combat stimuli, but effects did not vary as a function of combat severity. In the masked faces task, activation patterns did not vary as a function of stimulus. However, at the between-person level, amygdala activation during the masked faces task was inversely associated with PTSS. In respect to behavioral outcomes, higher PTSS were associated with a stronger Stroop effect, suggesting greater interference associated with combat words. Results are consistent with the premise that combat trauma results in hyperactivation in the ACC in response to combat stimuli, and, via its effect on PTSS, is associated with deficits in cognitive performance in the presence of combat stimuli. Across tasks, predeployment drinking was inversely associated with activation in the dACC but not the rACC or amygdala. Drinking may be a buffering factor, or negatively reinforcing in part because of its effects on normalizing brain response following trauma exposure. Alternatively, drinking may undermine adaptive functioning of the dACC when responding to traumatic stress cues. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
The Caledonian face test: A new test of face discrimination.
Logan, Andrew J; Wilkinson, Frances; Wilson, Hugh R; Gordon, Gael E; Loffler, Gunter
2016-02-01
This study aimed to develop a clinical test of face perception which is applicable to a wide range of patients and can capture normal variability. The Caledonian face test utilises synthetic faces which combine simplicity with sufficient realism to permit individual identification. Face discrimination thresholds (i.e. minimum difference between faces required for accurate discrimination) were determined in an "odd-one-out" task. The difference between faces was controlled by an adaptive QUEST procedure. A broad range of face discrimination sensitivity was determined from a group (N=52) of young adults (mean 5.75%; SD 1.18; range 3.33-8.84%). The test is fast (3-4 min), repeatable (test-re-test r(2)=0.795) and demonstrates a significant inversion effect. The potential to identify impairments of face discrimination was evaluated by testing LM who reported a lifelong difficulty with face perception. While LM's impairment for two established face tests was close to the criterion for significance (Z-scores of -2.20 and -2.27) for the Caledonian face test, her Z-score was -7.26, implying a more than threefold higher sensitivity. The new face test provides a quantifiable and repeatable assessment of face discrimination ability. The enhanced sensitivity suggests that the Caledonian face test may be capable of detecting more subtle impairments of face perception than available tests. Copyright © 2015 Elsevier Ltd. All rights reserved.
Riesenhuber, Maximilian; Wolff, Brian S.
2009-01-01
Summary A recent article in Acta Psychologica (“Picture-plane inversion leads to qualitative changes of face perception” by B. Rossion, 2008) criticized several aspects of an earlier paper of ours (Riesenhuber et al., “Face processing in humans is compatible with a simple shape-based model of vision”, Proc Biol Sci, 2004). We here address Rossion’s criticisms and correct some misunderstandings. To frame the discussion, we first review our previously presented computational model of face recognition in cortex (Jiang et al., “Evaluation of a shape-based model of human face discrimination using fMRI and behavioral techniques”, Neuron, 2006) that provides a concrete biologically plausible computational substrate for holistic coding, namely a neural representation learned for upright faces, in the spirit of the original simple-to-complex hierarchical model of vision by Hubel and Wiesel. We show that Rossion’s and others’ data support the model, and that there is actually a convergence of views on the mechanisms underlying face recognition, in particular regarding holistic processing. PMID:19665104
Liao, Ke; Zhu, Min; Ding, Lei
2013-08-01
The present study investigated the use of transform sparseness of cortical current density on human brain surface to improve electroencephalography/magnetoencephalography (EEG/MEG) inverse solutions. Transform sparseness was assessed by evaluating compressibility of cortical current densities in transform domains. To do that, a structure compression method from computer graphics was first adopted to compress cortical surface structure, either regular or irregular, into hierarchical multi-resolution meshes. Then, a new face-based wavelet method based on generated multi-resolution meshes was proposed to compress current density functions defined on cortical surfaces. Twelve cortical surface models were built by three EEG/MEG softwares and their structural compressibility was evaluated and compared by the proposed method. Monte Carlo simulations were implemented to evaluate the performance of the proposed wavelet method in compressing various cortical current density distributions as compared to other two available vertex-based wavelet methods. The present results indicate that the face-based wavelet method can achieve higher transform sparseness than vertex-based wavelet methods. Furthermore, basis functions from the face-based wavelet method have lower coherence against typical EEG and MEG measurement systems than vertex-based wavelet methods. Both high transform sparseness and low coherent measurements suggest that the proposed face-based wavelet method can improve the performance of L1-norm regularized EEG/MEG inverse solutions, which was further demonstrated in simulations and experimental setups using MEG data. Thus, this new transform on complicated cortical structure is promising to significantly advance EEG/MEG inverse source imaging technologies. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Discrimination of emotional facial expressions by tufted capuchin monkeys (Sapajus apella).
Calcutt, Sarah E; Rubin, Taylor L; Pokorny, Jennifer J; de Waal, Frans B M
2017-02-01
Tufted or brown capuchin monkeys (Sapajus apella) have been shown to recognize conspecific faces as well as categorize them according to group membership. Little is known, though, about their capacity to differentiate between emotionally charged facial expressions or whether facial expressions are processed as a collection of features or configurally (i.e., as a whole). In 3 experiments, we examined whether tufted capuchins (a) differentiate photographs of neutral faces from either affiliative or agonistic expressions, (b) use relevant facial features to make such choices or view the expression as a whole, and (c) demonstrate an inversion effect for facial expressions suggestive of configural processing. Using an oddity paradigm presented on a computer touchscreen, we collected data from 9 adult and subadult monkeys. Subjects discriminated between emotional and neutral expressions with an exceptionally high success rate, including differentiating open-mouth threats from neutral expressions even when the latter contained varying degrees of visible teeth and mouth opening. They also showed an inversion effect for facial expressions, results that may indicate that quickly recognizing expressions does not originate solely from feature-based processing but likely a combination of relational processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
A novel BCI based on ERP components sensitive to configural processing of human faces
NASA Astrophysics Data System (ADS)
Zhang, Yu; Zhao, Qibin; Jing, Jin; Wang, Xingyu; Cichocki, Andrzej
2012-04-01
This study introduces a novel brain-computer interface (BCI) based on an oddball paradigm using stimuli of facial images with loss of configural face information (e.g., inversion of face). To the best of our knowledge, till now the configural processing of human faces has not been applied to BCI but widely studied in cognitive neuroscience research. Our experiments confirm that the face-sensitive event-related potential (ERP) components N170 and vertex positive potential (VPP) have reflected early structural encoding of faces and can be modulated by the configural processing of faces. With the proposed novel paradigm, we investigate the effects of ERP components N170, VPP and P300 on target detection for BCI. An eight-class BCI platform is developed to analyze ERPs and evaluate the target detection performance using linear discriminant analysis without complicated feature extraction processing. The online classification accuracy of 88.7% and information transfer rate of 38.7 bits min-1 using stimuli of inverted faces with only single trial suggest that the proposed paradigm based on the configural processing of faces is very promising for visual stimuli-driven BCI applications.
A novel BCI based on ERP components sensitive to configural processing of human faces.
Zhang, Yu; Zhao, Qibin; Jin, Jing; Wang, Xingyu; Cichocki, Andrzej
2012-04-01
This study introduces a novel brain-computer interface (BCI) based on an oddball paradigm using stimuli of facial images with loss of configural face information (e.g., inversion of face). To the best of our knowledge, till now the configural processing of human faces has not been applied to BCI but widely studied in cognitive neuroscience research. Our experiments confirm that the face-sensitive event-related potential (ERP) components N170 and vertex positive potential (VPP) have reflected early structural encoding of faces and can be modulated by the configural processing of faces. With the proposed novel paradigm, we investigate the effects of ERP components N170, VPP and P300 on target detection for BCI. An eight-class BCI platform is developed to analyze ERPs and evaluate the target detection performance using linear discriminant analysis without complicated feature extraction processing. The online classification accuracy of 88.7% and information transfer rate of 38.7 bits min(-1) using stimuli of inverted faces with only single trial suggest that the proposed paradigm based on the configural processing of faces is very promising for visual stimuli-driven BCI applications.
Dissociation between recognition and detection advantage for facial expressions: a meta-analysis.
Nummenmaa, Lauri; Calvo, Manuel G
2015-04-01
Happy facial expressions are recognized faster and more accurately than other expressions in categorization tasks, whereas detection in visual search tasks is widely believed to be faster for angry than happy faces. We used meta-analytic techniques for resolving this categorization versus detection advantage discrepancy for positive versus negative facial expressions. Effect sizes were computed on the basis of the r statistic for a total of 34 recognition studies with 3,561 participants and 37 visual search studies with 2,455 participants, yielding a total of 41 effect sizes for recognition accuracy, 25 for recognition speed, and 125 for visual search speed. Random effects meta-analysis was conducted to estimate effect sizes at population level. For recognition tasks, an advantage in recognition accuracy and speed for happy expressions was found for all stimulus types. In contrast, for visual search tasks, moderator analysis revealed that a happy face detection advantage was restricted to photographic faces, whereas a clear angry face advantage was found for schematic and "smiley" faces. Robust detection advantage for nonhappy faces was observed even when stimulus emotionality was distorted by inversion or rearrangement of the facial features, suggesting that visual features primarily drive the search. We conclude that the recognition advantage for happy faces is a genuine phenomenon related to processing of facial expression category and affective valence. In contrast, detection advantages toward either happy (photographic stimuli) or nonhappy (schematic) faces is contingent on visual stimulus features rather than facial expression, and may not involve categorical or affective processing. (c) 2015 APA, all rights reserved).
Holistic face representation is highly orientation-specific.
Rosenthal, Gideon; Levakov, Gidon; Avidan, Galia
2017-09-29
It has long been argued that face processing requires disproportionate reliance on holistic processing (HP), relative to that required for nonface object recognition. Nevertheless, whether the holistic nature of face perception is achieved via a unique internal representation or by the employment of an automated attention mechanism is still debated. Previous studies had used the face inversion effect (FIE), a unique face-processing marker, or the face composite task, a gold standard paradigm measuring holistic processing, to examine the validity of these two different hypotheses, with some studies combining the two paradigms. However, the results of such studies remain inconclusive, particularly pertaining to the issue of the two proposed HP mechanisms-an internal representation as opposed to an automated attention mechanism. Here, using the complete composite paradigm design, we aimed to examine whether face rotation yields a nonlinear or a linear drop in HP, thus supporting an account that face processing is based either on an orientation-dependent internal representation or on automated attention. Our results reveal that even a relatively small perturbation in face orientation (30 deg away from upright) already causes a sharp decline in HP. These findings support the face internal representation hypothesis and the notion that the holistic processing of faces is highly orientation-specific.
Perceptual dehumanization of faces is activated by norm violations and facilitates norm enforcement.
Fincher, Katrina M; Tetlock, Philip E
2016-02-01
This article uses methods drawn from perceptual psychology to answer a basic social psychological question: Do people process the faces of norm violators differently from those of others--and, if so, what is the functional significance? Seven studies suggest that people process these faces different and the differential processing makes it easier to punish norm violators. Studies 1 and 2 use a recognition-recall paradigm that manipulated facial-inversion and spatial frequency to show that people rely upon face-typical processing less when they perceive norm violators' faces. Study 3 uses a facial composite task to demonstrate that the effect is actor dependent, not action dependent, and to suggest that configural processing is the mechanism of perceptual change. Studies 4 and 5 use offset faces to show that configural processing is only attenuated when they belong to perpetrators who are culpable. Studies 6 and 7 show that people find it easier to punish inverted faces and harder to punish faces displayed in low spatial frequency. Taken together, these data suggest a bidirectional flow of causality between lower-order perceptual and higher-order cognitive processes in norm enforcement. PsycINFO Database Record (c) 2016 APA, all rights reserved.
Explaining Sad People's Memory Advantage for Faces.
Hills, Peter J; Marquardt, Zoe; Young, Isabel; Goodenough, Imogen
2017-01-01
Sad people recognize faces more accurately than happy people (Hills et al., 2011). We devised four hypotheses for this finding that are tested between in the current study. The four hypotheses are: (1) sad people engage in more expert processing associated with face processing; (2) sad people are motivated to be more accurate than happy people in an attempt to repair their mood; (3) sad people have a defocused attentional strategy that allows more information about a face to be encoded; and (4) sad people scan more of the face than happy people leading to more facial features to be encoded. In Experiment 1, we found that dysphoria (sad mood often associated with depression) was not correlated with the face-inversion effect (a measure of expert processing) nor with response times but was correlated with defocused attention and recognition accuracy. Experiment 2 established that dysphoric participants detected changes made to more facial features than happy participants. In Experiment 3, using eye-tracking we found that sad-induced participants sampled more of the face whilst avoiding the eyes. Experiment 4 showed that sad-induced people demonstrated a smaller own-ethnicity bias. These results indicate that sad people show different attentional allocation to faces than happy and neutral people.
Dimitriou, D; Leonard, H C; Karmiloff-Smith, A; Johnson, M H; Thomas, M S C
2015-05-01
Configural processing in face recognition is a sensitivity to the spacing between facial features. It has been argued both that its presence represents a high level of expertise in face recognition, and also that it is a developmentally vulnerable process. We report a cross-syndrome investigation of the development of configural face recognition in school-aged children with autism, Down syndrome and Williams syndrome compared with a typically developing comparison group. Cross-sectional trajectory analyses were used to compare configural and featural face recognition utilising the 'Jane faces' task. Trajectories were constructed linking featural and configural performance either to chronological age or to different measures of mental age (receptive vocabulary, visuospatial construction), as well as the Benton face recognition task. An emergent inversion effect across age for detecting configural but not featural changes in faces was established as the marker of typical development. Children from clinical groups displayed atypical profiles that differed across all groups. We discuss the implications for the nature of face processing within the respective developmental disorders, and how the cross-sectional syndrome comparison informs the constraints that shape the typical development of face recognition. © 2014 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.
Expertise for upright faces improves the precision but not the capacity of visual working memory.
Lorenc, Elizabeth S; Pratte, Michael S; Angeloni, Christopher F; Tong, Frank
2014-10-01
Considerable research has focused on how basic visual features are maintained in working memory, but little is currently known about the precision or capacity of visual working memory for complex objects. How precisely can an object be remembered, and to what extent might familiarity or perceptual expertise contribute to working memory performance? To address these questions, we developed a set of computer-generated face stimuli that varied continuously along the dimensions of age and gender, and we probed participants' memories using a method-of-adjustment reporting procedure. This paradigm allowed us to separately estimate the precision and capacity of working memory for individual faces, on the basis of the assumptions of a discrete capacity model, and to assess the impact of face inversion on memory performance. We found that observers could maintain up to four to five items on average, with equally good memory capacity for upright and upside-down faces. In contrast, memory precision was significantly impaired by face inversion at every set size tested. Our results demonstrate that the precision of visual working memory for a complex stimulus is not strictly fixed but, instead, can be modified by learning and experience. We find that perceptual expertise for upright faces leads to significant improvements in visual precision, without modifying the capacity of working memory.
NASA Technical Reports Server (NTRS)
1997-01-01
Session MP4 includes short reports on: (1) Face Recognition in Microgravity: Is Gravity Direction Involved in the Inversion Effect?; (2) Motor Timing under Microgravity; (3) Perceived Self-Motion Assessed by Computer-Generated Animations: Complexity and Reliability; (4) Prolonged Weightlessness Reference Frames and Visual Symmetry Detection; (5) Mental Representation of Gravity During a Locomotor Task; and (6) Haptic Perception in Weightlessness: A Sense of Force or a Sense of Effort?
Toward a unified model of face and object recognition in the human visual system
Wallis, Guy
2013-01-01
Our understanding of the mechanisms and neural substrates underlying visual recognition has made considerable progress over the past 30 years. During this period, accumulating evidence has led many scientists to conclude that objects and faces are recognised in fundamentally distinct ways, and in fundamentally distinct cortical areas. In the psychological literature, in particular, this dissociation has led to a palpable disconnect between theories of how we process and represent the two classes of object. This paper follows a trend in part of the recognition literature to try to reconcile what we know about these two forms of recognition by considering the effects of learning. Taking a widely accepted, self-organizing model of object recognition, this paper explains how such a system is affected by repeated exposure to specific stimulus classes. In so doing, it explains how many aspects of recognition generally regarded as unusual to faces (holistic processing, configural processing, sensitivity to inversion, the other-race effect, the prototype effect, etc.) are emergent properties of category-specific learning within such a system. Overall, the paper describes how a single model of recognition learning can and does produce the seemingly very different types of representation associated with faces and objects. PMID:23966963
Allergic conditions and risk of glioma and meningioma in the CERENAT case-control study.
Pouchieu, Camille; Raherison, Chantal; Piel, Clément; Migault, Lucile; Carles, Camille; Fabbro-Perray, Pascale; Loiseau, Hugues; Guillamo, Jean-Sébastien; Lebailly, Pierre; Baldi, Isabelle
2018-06-01
Inverse association between allergic conditions and glioma risk has been consistently reported in epidemiological studies with little attention paid to potential environmental confounders; the association with meningioma risk is less consistent. We examined the association between allergy history and risk of glioma and meningioma in adults using data from the CERENAT (CEREbral tumors: a NATional study) multicenter case-control study carried out in 4 areas in France in 2004-2010. Participants' histories of doctor-diagnosed allergic asthma, eczema, rhinitis/hay fever and other allergic conditions were collected at onset through a detailed questionnaire delivered in a face-to-face interview. Conditional logistic regression for matched sets was adjusted for participants' educational level and mobile phone use. A total of 273 glioma cases, 218 meningioma cases and 982 matched controls selected from the local electoral rolls were analyzed. A significant inverse association was found between glioma and a history of any allergy (OR 0.52, 95% CI 0.36-0.75), with a dose-effect relationship with the number of allergic conditions reported (p-trend = 0.001) and a particularly strong association with hay fever/allergic rhinitis (OR 0.46, 95% CI 0.30-0.72). Interestingly, associations with glioma risk were more pronounced in women. For meningioma, no association was observed with overall or specific allergic conditions. Our findings confirmed the inverse association between allergic conditions and glioma risk but questioned the role of allergy in meningioma risk. Future research is needed to clarify the biological mechanism of overall allergy and allergic rhinitis on glioma and to confirm the different effect by gender.
Dennett, Hugh W; McKone, Elinor; Tavashmi, Raka; Hall, Ashleigh; Pidcock, Madeleine; Edwards, Mark; Duchaine, Bradley
2012-06-01
Many research questions require a within-class object recognition task matched for general cognitive requirements with a face recognition task. If the object task also has high internal reliability, it can improve accuracy and power in group analyses (e.g., mean inversion effects for faces vs. objects), individual-difference studies (e.g., correlations between certain perceptual abilities and face/object recognition), and case studies in neuropsychology (e.g., whether a prosopagnosic shows a face-specific or object-general deficit). Here, we present such a task. Our Cambridge Car Memory Test (CCMT) was matched in format to the established Cambridge Face Memory Test, requiring recognition of exemplars across view and lighting change. We tested 153 young adults (93 female). Results showed high reliability (Cronbach's alpha = .84) and a range of scores suitable both for normal-range individual-difference studies and, potentially, for diagnosis of impairment. The mean for males was much higher than the mean for females. We demonstrate independence between face memory and car memory (dissociation based on sex, plus a modest correlation between the two), including where participants have high relative expertise with cars. We also show that expertise with real car makes and models of the era used in the test significantly predicts CCMT performance. Surprisingly, however, regression analyses imply that there is an effect of sex per se on the CCMT that is not attributable to a stereotypical male advantage in car expertise.
Detection of emotional faces: salient physical features guide effective visual search.
Calvo, Manuel G; Nummenmaa, Lauri
2008-08-01
In this study, the authors investigated how salient visual features capture attention and facilitate detection of emotional facial expressions. In a visual search task, a target emotional face (happy, disgusted, fearful, angry, sad, or surprised) was presented in an array of neutral faces. Faster detection of happy and, to a lesser extent, surprised and disgusted faces was found both under upright and inverted display conditions. Inversion slowed down the detection of these faces less than that of others (fearful, angry, and sad). Accordingly, the detection advantage involves processing of featural rather than configural information. The facial features responsible for the detection advantage are located in the mouth rather than the eye region. Computationally modeled visual saliency predicted both attentional orienting and detection. Saliency was greatest for the faces (happy) and regions (mouth) that were fixated earlier and detected faster, and there was close correspondence between the onset of the modeled saliency peak and the time at which observers initially fixated the faces. The authors conclude that visual saliency of specific facial features--especially the smiling mouth--is responsible for facilitated initial orienting, which thus shortens detection. (PsycINFO Database Record (c) 2008 APA, all rights reserved).
Face processing among twins with and without autism: social correlates and twin concordance.
Neuhaus, Emily; Kresse, Anna; Faja, Susan; Bernier, Raphael A; Webb, Sara Jane
2016-01-01
Autism spectrum disorder (ASD) has a strong heritable basis, as evidenced by twin concordance rates. Within ASD, symptom domains may arise via independent genetic contributions, with varying heritabilities and genetic mechanisms. In this article, we explore social functioning in the form of (i) electrophysiological and behavioral measures of face processing (P1 and N170) and (ii) social behavior among child and adolescent twins with (N = 52) and without ASD (N = 66). Twins without ASD had better holistic face processing and face memory, faster P1 responses and greater sensitivity to the effects of facial inversion on P1. In contrast, N170 responses to faces were similar across diagnosis, with more negative amplitudes for faces vs non-face images. Across the sample, stronger social skills and fewer social difficulties were associated with faster P1 and N170 responses to upright faces, and better face memory. Twins were highly correlated within pairs across most measures, but correlations were significantly stronger for monozygotic vs dizygotic pairs on N170 latency and social problems. We suggest common developmental influences across twins for face processing and social behavior, but highlight (i) neural speed of face processing and (ii) social difficulties as important avenues in the search for genetic underpinnings in ASD. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
Sanchez-Lopez, Alvaro; Vanderhasselt, Marie-Anne; Allaert, Jens; Baeken, Chris; De Raedt, Rudi
2018-06-01
Attention to relevant emotional information in the environment is an important process related to vulnerability and resilience for mood and anxiety disorders. In the present study, the effects of left and right dorsolateral prefrontal cortex (i.e., DLPFC) stimulation on attentional mechanisms of emotional processing were tested and contrasted. A sample of 54 healthy participants received 20 min of active and sham anodal transcranial direct current stimulation (i.e., tDCS) either of the left (n = 27) or of the right DLPFC (n = 27) on two separate days. The anode electrode was placed over the left or the right DLPFC, the cathode over the corresponding contra lateral supraorbital area. After each neurostimulation session, participants completed an eye-tracking task assessing direct processes of attentional engagement towards and attentional disengagement away from emotional faces (happy, disgusted, and sad expressions). Compared to sham, active tDCS over the left DLPFC led to faster gaze disengagement, whereas active tDCS over the right DLPFC led to slower gaze disengagement from emotional faces. Between-group comparisons showed that such inverse change patterns were significantly different and generalized for all types of emotion. Our findings support a lateralized role of left and right DLPFC activity in enhancing/worsening the top-down regulation of emotional attention processing. These results support the rationale of new therapies for affective disorders aimed to increase the activation of the left over the right DLPFC in combination with attentional control training, and identify specific target attention mechanisms to be trained.
Generalised filtering and stochastic DCM for fMRI.
Li, Baojuan; Daunizeau, Jean; Stephan, Klaas E; Penny, Will; Hu, Dewen; Friston, Karl
2011-09-15
This paper is about the fitting or inversion of dynamic causal models (DCMs) of fMRI time series. It tries to establish the validity of stochastic DCMs that accommodate random fluctuations in hidden neuronal and physiological states. We compare and contrast deterministic and stochastic DCMs, which do and do not ignore random fluctuations or noise on hidden states. We then compare stochastic DCMs, which do and do not ignore conditional dependence between hidden states and model parameters (generalised filtering and dynamic expectation maximisation, respectively). We first characterise state-noise by comparing the log evidence of models with different a priori assumptions about its amplitude, form and smoothness. Face validity of the inversion scheme is then established using data simulated with and without state-noise to ensure that DCM can identify the parameters and model that generated the data. Finally, we address construct validity using real data from an fMRI study of internet addiction. Our analyses suggest the following. (i) The inversion of stochastic causal models is feasible, given typical fMRI data. (ii) State-noise has nontrivial amplitude and smoothness. (iii) Stochastic DCM has face validity, in the sense that Bayesian model comparison can distinguish between data that have been generated with high and low levels of physiological noise and model inversion provides veridical estimates of effective connectivity. (iv) Relaxing conditional independence assumptions can have greater construct validity, in terms of revealing group differences not disclosed by variational schemes. Finally, we note that the ability to model endogenous or random fluctuations on hidden neuronal (and physiological) states provides a new and possibly more plausible perspective on how regionally specific signals in fMRI are generated. Copyright © 2011. Published by Elsevier Inc.
Explaining Sad People’s Memory Advantage for Faces
Hills, Peter J.; Marquardt, Zoe; Young, Isabel; Goodenough, Imogen
2017-01-01
Sad people recognize faces more accurately than happy people (Hills et al., 2011). We devised four hypotheses for this finding that are tested between in the current study. The four hypotheses are: (1) sad people engage in more expert processing associated with face processing; (2) sad people are motivated to be more accurate than happy people in an attempt to repair their mood; (3) sad people have a defocused attentional strategy that allows more information about a face to be encoded; and (4) sad people scan more of the face than happy people leading to more facial features to be encoded. In Experiment 1, we found that dysphoria (sad mood often associated with depression) was not correlated with the face-inversion effect (a measure of expert processing) nor with response times but was correlated with defocused attention and recognition accuracy. Experiment 2 established that dysphoric participants detected changes made to more facial features than happy participants. In Experiment 3, using eye-tracking we found that sad-induced participants sampled more of the face whilst avoiding the eyes. Experiment 4 showed that sad-induced people demonstrated a smaller own-ethnicity bias. These results indicate that sad people show different attentional allocation to faces than happy and neutral people. PMID:28261138
Associative (prosop)agnosia without (apparent) perceptual deficits: a case-study.
Anaki, David; Kaufman, Yakir; Freedman, Morris; Moscovitch, Morris
2007-04-09
In associative agnosia early perceptual processing of faces or objects are considered to be intact, while the ability to access stored semantic information about the individual face or object is impaired. Recent claims, however, have asserted that associative agnosia is also characterized by deficits at the perceptual level, which are too subtle to be detected by current neuropsychological tests. Thus, the impaired identification of famous faces or common objects in associative agnosia stems from difficulties in extracting the minute perceptual details required to identify a face or an object. In the present study, we report the case of a patient DBO with a left occipital infarct, who shows impaired object and famous face recognition. Despite his disability, he exhibits a face inversion effect, and is able to select a famous face from among non-famous distractors. In addition, his performance is normal in an immediate and delayed recognition memory for faces, whose external features were deleted. His deficits in face recognition are apparent only when he is required to name a famous face, or select two faces from among a triad of famous figures based on their semantic relationships (a task which does not require access to names). The nature of his deficits in object perception and recognition are similar to his impairments in the face domain. This pattern of behavior supports the notion that apperceptive and associative agnosia reflect distinct and dissociated deficits, which result from damage to different stages of the face and object recognition process.
Lapate, R. C.; Rokers, B.; Tromp, D. P. M.; Orfali, N. S.; Oler, J. A.; Doran, S. T.; Adluru, N.; Alexander, A. L.; Davidson, R. J.
2016-01-01
Conscious awareness of negative cues is thought to enhance emotion-regulatory capacity, but the neural mechanisms underlying this effect are unknown. Using continuous flash suppression (CFS) in the MRI scanner, we manipulated visual awareness of fearful faces during an affect misattribution paradigm, in which preferences for neutral objects can be biased by the valence of a previously presented stimulus. The amygdala responded to fearful faces independently of awareness. However, when awareness of fearful faces was prevented, individuals with greater amygdala responses displayed a negative bias toward unrelated novel neutral faces. In contrast, during the aware condition, inverse coupling between the amygdala and prefrontal cortex reduced this bias, particularly among individuals with higher structural connectivity in the major white matter pathway connecting the prefrontal cortex and amygdala. Collectively, these results indicate that awareness promotes the function of a critical emotion-regulatory network targeting the amygdala, providing a mechanistic account for the role of awareness in emotion regulation. PMID:27181344
Garman, Heather D.; Spaulding, Christine J.; Webb, Sara Jane; Mikami, Amori Yee; Morris, James P.
2016-01-01
This study examined social motivation and early-stage face perception as frameworks for understanding impairments in facial emotion recognition (FER) in a well-characterized sample of youth with autism spectrum disorders (ASD). Early-stage face perception (N170 event-related potential latency) was recorded while participants completed a standardized FER task, while social motivation was obtained via parent report. Participants with greater social motivation exhibited poorer FER, while those with shorter N170 latencies exhibited better FER for child angry faces stimuli. Social motivation partially mediated the relationship between a faster N170 and better FER. These effects were all robust to variations in IQ, age, and ASD severity. These findings augur against theories implicating social motivation as uniformly valuable for individuals with ASD, and augment models suggesting a close link between early-stage face perception, social motivation, and FER in this population. Broader implications for models and development of FER in ASD are discussed. PMID:26743637
Garman, Heather D; Spaulding, Christine J; Webb, Sara Jane; Mikami, Amori Yee; Morris, James P; Lerner, Matthew D
2016-12-01
This study examined social motivation and early-stage face perception as frameworks for understanding impairments in facial emotion recognition (FER) in a well-characterized sample of youth with autism spectrum disorders (ASD). Early-stage face perception (N170 event-related potential latency) was recorded while participants completed a standardized FER task, while social motivation was obtained via parent report. Participants with greater social motivation exhibited poorer FER, while those with shorter N170 latencies exhibited better FER for child angry faces stimuli. Social motivation partially mediated the relationship between a faster N170 and better FER. These effects were all robust to variations in IQ, age, and ASD severity. These findings augur against theories implicating social motivation as uniformly valuable for individuals with ASD, and augment models suggesting a close link between early-stage face perception, social motivation, and FER in this population. Broader implications for models and development of FER in ASD are discussed.
Zeugin, David; Arfa, Norhan; Notter, Michael; Murray, Micah M; Ionta, Silvio
2017-08-30
Face recognition is an apparently straightforward but, in fact, complex ability, encompassing the activation of at least visual and somatosensory representations. Understanding how identity shapes the interplay between these face-related affordances could clarify the mechanisms of self-other discrimination. To this aim, we exploited the so-called "face inversion effect" (FIE), a specific bias in the mental rotation of face images (of other people): with respect to inanimate objects, face images require longer time to be mentally rotated from the upside-down. Via the FIE, which suggests the activation of somatosensory mechanisms, we assessed identity-related changes in the interplay between visual and somatosensory affordances between self- and other-face representations. Methodologically, to avoid the potential interference of the somatosensory feedback associated with musculoskeletal movements, we introduced the tracking of gaze direction to record participants' response. Response times from twenty healthy participants showed the larger FIE for self- than other-faces, suggesting that the impact of somatosensory affordances on mental representation of faces varies according to identity. The present study lays the foundations of a quantifiable method to implicitly assess self-other discrimination, with possible translational benefits for early diagnosis of face processing disturbances (e.g. prosopagnosia), and for neurophysiological studies on self-other discrimination in ethological settings. Copyright © 2017 Elsevier B.V. All rights reserved.
How Negative Social Bias Affects Memory for Faces: An Electrical Neuroimaging Study
Proverbio, Alice Mado; La Mastra, Francesca; Zani, Alberto
2016-01-01
During social interactions, we make inferences about people’s personal characteristics based on their appearance. These inferences form a potential prejudice that can positively or negatively bias our interaction with them. Not much is known about the effects of negative bias on face perception and the ability to recognize people faces. This ability was investigated by recording event-related potentials (ERPs) from 128 sites in 16 volunteers. In the first session (encoding), they viewed 200 faces associated with a short fictional story that described anecdotal positive or negative characteristics about each person. In the second session (recognition), they underwent an old/new memory test, in which they had to distinguish 100 new faces from the previously shown faces. ERP data relative to the encoding phase showed a larger anterior negativity in response to negatively (vs. positively) biased faces, indicating an additional processing of faces with unpleasant social traits. In the recognition task, ERPs recorded in response to new faces elicited a larger FN400 than to old faces, and to positive than negative faces. Additionally, old faces elicited a larger Old-New parietal response than new faces, in the form of an enlarged late positive (LPC) component. An inverse solution SwLORETA (450–550 ms) indicated that remembering old faces was associated with the activation of right superior frontal gyrus (SFG), left medial temporal gyrus, and right fusiform gyrus. Only negatively connoted faces strongly activated the limbic and parahippocampal areas and the left SFG. A dissociation was found between familiarity (modulated by negative bias) and recollection (distinguishing old from new faces). PMID:27655327
Does Face Inversion Change Spatial Frequency Tuning?
ERIC Educational Resources Information Center
Willenbockel, Verena; Fiset, Daniel; Chauvin, Alan; Blais, Caroline; Arguin, Martin; Tanaka, James W.; Bub, Daniel N.; Gosselin, Frederic
2010-01-01
The authors examined spatial frequency (SF) tuning of upright and inverted face identification using an SF variant of the Bubbles technique (F. Gosselin & P. G. Schyns, 2001). In Experiment 1, they validated the SF Bubbles technique in a plaid detection task. In Experiments 2a-c, the SFs used for identifying upright and inverted inner facial…
Peters, Judith C; Vlamings, Petra; Kemner, Chantal
2013-05-01
Face perception in adults depends on skilled processing of interattribute distances ('configural' processing), which is disrupted for faces presented in inverted orientation (face inversion effect or FIE). Children are not proficient in configural processing, and this might relate to an underlying immaturity to use facial information in low spatial frequency (SF) ranges, which capture the coarse information needed for configural processing. We hypothesized that during adolescence a shift from use of high to low SF information takes place. Therefore, we studied the influence of SF content on neural face processing in groups of children (9-10 years), adolescents (14-15 years) and young adults (21-29 years) by measuring event-related potentials (ERPs) to upright and inverted faces which varied in SF content. Results revealed that children show a neural FIE in early processing stages (i.e. P1; generated in early visual areas), suggesting a superficial, global facial analysis. In contrast, ERPs of adults revealed an FIE at later processing stages (i.e. N170; generated in face-selective, higher visual areas). Interestingly, adolescents showed FIEs in both processing stages, suggesting a hybrid developmental stage. Furthermore, adolescents and adults showed FIEs for stimuli containing low SF information, whereas such effects were driven by both low and high SF information in children. These results indicate that face processing has a protracted maturational course into adolescence, and is dependent on changes in SF processing. During adolescence, sensitivity to configural cues is developed, which aids the fast and holistic processing that is so special for faces. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
ERIC Educational Resources Information Center
Sangwin, Christopher J.; Jones, Ian
2017-01-01
In this paper we report the results of an experiment designed to test the hypothesis that when faced with a question involving the inverse direction of a reversible mathematical process, students solve a multiple-choice version by verifying the answers presented to them by the direct method, not by undertaking the actual inverse calculation.…
Is the Thatcher Illusion Modulated by Face Familiarity? Evidence from an Eye Tracking Study
2016-01-01
Thompson (1980) first detected and described the Thatcher Illusion, where participants instantly perceive an upright face with inverted eyes and mouth as grotesque, but fail to do so when the same face is inverted. One prominent but controversial explanation is that the processing of configural information is disrupted in inverted faces. Studies investigating the Thatcher Illusion either used famous faces or non-famous faces. Highly familiar faces were often thought to be processed in a pronounced configural mode, so they seem ideal candidates to be tested in one Thatcher study against unfamiliar faces–but this has never been addressed so far. In our study, participants evaluated 16 famous and 16 non-famous faces for their grotesqueness. We tested whether familiarity (famous/non-famous faces) modulates reaction times, correctness of grotesqueness assessments (accuracy), and eye movement patterns for the factors orientation (upright/inverted) and Thatcherisation (Thatcherised/non-Thatcherised). On a behavioural level, familiarity effects were only observable via face inversion (higher accuracy and sensitivity for famous compared to non-famous faces) but not via Thatcherisation. Regarding eye movements, however, Thatcherisation influenced the scanning of famous and non-famous faces, for instance, in scanning the mouth region of the presented faces (higher number, duration and dwell time of fixations for famous compared to non-famous faces if Thatcherised). Altogether, famous faces seem to be processed in a more elaborate, more expertise-based way than non-famous faces, whereas non-famous, inverted faces seem to cause difficulties in accurate and sensitive processing. Results are further discussed in the face of existing studies of familiar vs. unfamiliar face processing. PMID:27776145
Zeng, F-f; Xu, C-h; Liu, Y-t; Fan, Y-y; Lin, X-l; Lu, Y-k; Zhang, C-x; Chen, Y-m
2014-02-04
Intakes of choline and betaine have been inversely related to the risk of various neoplasms, but scant data exist on nasopharyngeal carcinoma (NPC). We examined the association between consumption of choline and betaine and risk of NPC. We conducted a case-control study with 600 incident NPC patients and 600 controls 1 : 1 matched by age, sex and household type in Guangdong, China. Dietary intake was assessed by a food frequency questionnaire through face-to-face interview. Intakes of total choline, betaine and choline+betaine were inversely related to NPC after adjustment for various lifestyle and dietary factors (all P-trend <0.001). Adjusted odds ratios (95% CI) for quartile 4 (vs quartile 1) were 0.42 (0.29, 0.61) for total choline, 0.50 (0.35, 0.72) for betaine and 0.44 (0.30, 0.64) for betaine+total choline. Regarding various sources of choline, lower NPC risk was associated with greater intakes of choline from phosphatidylcholine, free choline, glycerophosphocholine and phosphocholine, but not sphingomyelin. These findings are consistent with a beneficial effect of choline and betaine intakes on carcinogenesis.
Zeng, F-f; Xu, C-h; Liu, Y-t; Fan, Y-y; Lin, X-l; Lu, Y-k; Zhang, C-x; Chen, Y-m
2014-01-01
Background: Intakes of choline and betaine have been inversely related to the risk of various neoplasms, but scant data exist on nasopharyngeal carcinoma (NPC). We examined the association between consumption of choline and betaine and risk of NPC. Methods: We conducted a case–control study with 600 incident NPC patients and 600 controls 1 : 1 matched by age, sex and household type in Guangdong, China. Dietary intake was assessed by a food frequency questionnaire through face-to-face interview. Results: Intakes of total choline, betaine and choline+betaine were inversely related to NPC after adjustment for various lifestyle and dietary factors (all P-trend <0.001). Adjusted odds ratios (95% CI) for quartile 4 (vs quartile 1) were 0.42 (0.29, 0.61) for total choline, 0.50 (0.35, 0.72) for betaine and 0.44 (0.30, 0.64) for betaine+total choline. Regarding various sources of choline, lower NPC risk was associated with greater intakes of choline from phosphatidylcholine, free choline, glycerophosphocholine and phosphocholine, but not sphingomyelin. Conclusion: These findings are consistent with a beneficial effect of choline and betaine intakes on carcinogenesis. PMID:24169354
Chu, Denise A; Bryant, Richard A; Gatt, Justine M; Harris, Anthony Wf
2018-03-01
Posttraumatic stress disorder and childhood trauma frequently co-occur. Both are associated with abnormal neural responses to salient emotion stimuli. As childhood trauma is a risk factor for posttraumatic stress disorder, differentiating between their neurophysiological effects is necessary to elucidate the neural pathways by which childhood trauma exposure contributes to increased posttraumatic stress disorder risks. Face-specific N170 evoked response potentials for backward-masked (non-conscious) and conscious threat (fear, angry) and non-threat (happy) faces were measured in 77 adults (18-64 years old, 64% women, 78% right-handed) symptomatic for posttraumatic stress disorder. Differences in N170 peak amplitudes for fear-versus-happy and angry-versus-happy faces at bilateral temporo-occipital (T5, T6) sites were computed. The effect of cumulative exposure to childhood interpersonal trauma, other childhood trauma, adult trauma, depression and posttraumatic stress disorder symptom severity on the N170 response was assessed using hierarchical multiple regression analyses. T5 N170 peak amplitudes for non-conscious fear-versus-happy faces were inversely related to cumulative childhood interpersonal trauma after accounting for socio-demographic, clinical symptom and other trauma factors. Posttraumatic stress disorder Avoidance was positively associated with N170 peak amplitudes for non-conscious fear-versus-happy faces, primarily due to reduced N170 responsivity to happy faces. Childhood interpersonal trauma exposure is associated with reduced discrimination between fear and happy faces, while avoidance symptom severity is associated with dampened responsivity to automatically processed happy faces in posttraumatic stress disorder adults. Results are discussed in terms of the likely contributions of impaired threat discrimination and deficient reward processing during neural processing of salient emotion stimuli, to increased risks of posttraumatic stress disorder onset and chronicity in childhood interpersonal trauma-exposed adults.
Busigny, Thomas; Van Belle, Goedele; Jemel, Boutheina; Hosein, Anthony; Joubert, Sven; Rossion, Bruno
2014-04-01
Recent studies have provided solid evidence for pure cases of prosopagnosia following brain damage. The patients reported so far have posterior lesions encompassing either or both the right inferior occipital cortex and fusiform gyrus, and exhibit a critical impairment in generating a sufficiently detailed holistic percept to individualize faces. Here, we extended these observations to include the prosopagnosic patient LR (Bukach, Bub, Gauthier, & Tarr, 2006), whose damage is restricted to the anterior region of the right temporal lobe. First, we report that LR is able to discriminate parametrically defined individual exemplars of nonface object categories as accurately and quickly as typical observers, which suggests that the visual similarity account of prosopagnosia does not explain his impairments. Then, we show that LR does not present with the typical face inversion effect, whole-part advantage, or composite face effect and, therefore, has impaired holistic perception of individual faces. Moreover, the patient is more impaired at matching faces when the facial part he fixates is masked than when it is selectively revealed by means of gaze contingency. Altogether these observations support the view that the nature of the critical face impairment does not differ qualitatively across patients with acquired prosopagnosia, regardless of the localization of brain damage: all these patients appear to be impaired to some extent at what constitutes the heart of our visual expertise with faces, namely holistic perception at a sufficiently fine-grained level of resolution to discriminate exemplars of the face class efficiently. This conclusion raises issues regarding the existing criteria for diagnosis/classification of patients as cases of apperceptive or associative prosopagnosia. Copyright © 2014 Elsevier Ltd. All rights reserved.
Inverse grading and hydraulic equivalence in grain-flow deposits
Sallenger, A. H.
1979-01-01
Inversely graded grain-flow deposits are characterized by a hydraulic equivalence that differs from that based on settling velocities or entrainment. Dispersive equivalence, derived from the dispersive pressure hypothesis on how inverse grading develops, was found to agree reasonably well with observed relationships between grain sizes and densities in grain-flow deposits. Furthermore, observed relationships in deposits formed in subaerial and subaqueous environments were found to be independent of fluid density as is required by dispersive equivalence. The results suggest that dispersive pressure controls the development of the inverse grading common to beach foreshore laminations, slip-face foreset strata, the basal parts of some coarse-grained turbidites, and other diverse deposits.
Vrancken, Leia; Germeys, Filip; Verfaillie, Karl
2017-01-01
A considerable amount of research on identity recognition and emotion identification with the composite design points to the holistic processing of these aspects in faces and bodies. In this paradigm, the interference from a nonattended face half on the perception of the attended half is taken as evidence for holistic processing (i.e., a composite effect). Far less research, however, has been dedicated to the concept of gaze. Nonetheless, gaze perception is a substantial component of face and body perception, and holds critical information for everyday communicative interactions. Furthermore, the ability of human observers to detect direct versus averted eye gaze is effortless, perhaps similar to identity perception and emotion recognition. However, the hypothesis of holistic perception of eye gaze has never been tested directly. Research on gaze perception with the composite design could facilitate further systematic comparison with other aspects of face and body perception that have been investigated using the composite design (i.e., identity and emotion). In the present research, a composite design was administered to assess holistic processing of gaze cues in faces (Experiment 1) and bodies (Experiment 2). Results confirmed that eye and head orientation (Experiment 1A) and head and body orientation (Experiment 2A) are integrated in a holistic manner. However, the composite effect was not completely disrupted by inversion (Experiments 1B and 2B), a finding that will be discussed together with implications for future research.
Medicine, morality and health care social media.
Timimi, Farris K
2012-08-02
Social media includes many different forms of technology including online forums, blogs, microblogs (i.e. Twitter), wikipedias, video blogs, social networks and podcasting. The use of social media has grown exponentially and time spent on social media sites now represents one in five minutes spent online. Concomitant with this online growth, there has been an inverse trajectory in direct face-to-face patient-provider moments, which continue to become scarcer across the spectrum of health care. In contrast to standard forms of engagement and education, social media has advantages to include profound reach, immediate availability, an archived presence and broad accessibility. Our opportunity as health care providers to partner with our patients has never been greater, yet all too often we allow risk averse fears to limit our ability to truly leverage our good content effectively to the online community. This risk averse behavior truly limits our capacity to effectively engage our patients where they are--online.
Albonico, Andrea; Malaspina, Manuela; Daini, Roberta
2017-09-01
The Benton Facial Recognition Test (BFRT) and Cambridge Face Memory Test (CFMT) are two of the most common tests used to assess face discrimination and recognition abilities and to identify individuals with prosopagnosia. However, recent studies highlighted that participant-stimulus match ethnicity, as much as gender, has to be taken into account in interpreting results from these tests. Here, in order to obtain more appropriate normative data for an Italian sample, the CFMT and BFRT were administered to a large cohort of young adults. We found that scores from the BFRT are not affected by participants' gender and are only slightly affected by participant-stimulus ethnicity match, whereas both these factors seem to influence the scores of the CFMT. Moreover, the inclusion of a sample of individuals with suspected face recognition impairment allowed us to show that the use of more appropriate normative data can increase the BFRT efficacy in identifying individuals with face discrimination impairments; by contrast, the efficacy of the CFMT in classifying individuals with a face recognition deficit was confirmed. Finally, our data show that the lack of inversion effect (the difference between the total score of the upright and inverted versions of the CFMT) could be used as further index to assess congenital prosopagnosia. Overall, our results confirm the importance of having norms derived from controls with a similar experience of faces as the "potential" prosopagnosic individuals when assessing face recognition abilities.
Early sensitivity for eyes within faces: a new neuronal account of holistic and featural processing
Nemrodov, Dan; Anderson, Thomas; Preston, Frank F.; Itier, Roxane J.
2017-01-01
Eyes are central to face processing however their role in early face encoding as reflected by the N170 ERP component is unclear. Using eye tracking to enforce fixation on specific facial features, we found that the N170 was larger for fixation on the eyes compared to fixation on the forehead, nasion, nose or mouth, which all yielded similar amplitudes. This eye sensitivity was seen in both upright and inverted faces and was lost in eyeless faces, demonstrating it was due to the presence of eyes at fovea. Upright eyeless faces elicited largest N170 at nose fixation. Importantly, the N170 face inversion effect (FIE) was strongly attenuated in eyeless faces when fixation was on the eyes but was less attenuated for nose fixation and was normal when fixation was on the mouth. These results suggest the impact of eye removal on the N170 FIE is a function of the angular distance between the fixated feature and the eye location. We propose the Lateral Inhibition, Face Template and Eye Detector based (LIFTED) model which accounts for all the present N170 results including the FIE and its interaction with eye removal. Although eyes elicit the largest N170 response, reflecting the activity of an eye detector, the processing of upright faces is holistic and entails an inhibitory mechanism from neurons coding parafoveal information onto neurons coding foveal information. The LIFTED model provides a neuronal account of holistic and featural processing involved in upright and inverted faces and offers precise predictions for further testing. PMID:24768932
Gender interactions in the recognition of emotions and conduct symptoms in adolescents.
Halász, József; Aspán, Nikoletta; Bozsik, Csilla; Gádoros, Júlia; Inántsy-Pap, Judit
2014-01-01
According to literature data, impairment in the recognition of emotions might be related to antisocial developmental pathway. In the present study, the relationship between gender-specific interaction of emotion recognition and conduct symptoms were studied in non-clinical adolescents. After informed consent, 29 boys and 24 girls (13-16 years, 14 ± 0.1 years) participated in the study. The parent version of the Strengths and Difficulties Questionnaire was used to assess behavioral problems. The recognition of basic emotions was analyzed according to both the gender of the participants and the gender of the stimulus faces via the "Facial Expressions of Emotion- Stimuli and Tests". Girls were significantly better than boys in the recognition of disgust, irrespective from the gender of the stimulus faces, albeit both genders were significantly better in the recognition of disgust in the case of male stimulus faces compared to female stimulus faces. Both boys and girls were significantly better in the recognition of sadness in the case of female stimulus faces compared to male stimulus faces. There was no gender effect (neither participant nor stimulus faces) in the recognition of other emotions. Conduct scores in boys were inversely correlated with the recognition of fear in male stimulus faces (R=-0.439, p<0.05) and with overall emotion recognition in male stimulus faces (R=-0.558, p<0.01). In girls, conduct scores were shown a tendency for positive correlation with disgust recognition in female stimulus faces (R=0.376, p<0.07). A gender-specific interaction between the recognition of emotions and antisocial developmentalpathway is suggested.
Are two plasma equilibrium states possible when the emission coefficient exceeds unity?
NASA Astrophysics Data System (ADS)
Campanell, M. D.; Umansky, M. V.
2017-05-01
Two floating sheath solutions with strong electron emission in planar geometry have been proposed, a "space-charge limited" (SCL) sheath and an "inverse" sheath. SCL and inverse models contain different assumptions about conditions outside the sheath (e.g., the velocity of ions entering the sheath). So it is not yet clear whether both sheaths are possible in practice, or only one. Here we treat the global presheath-sheath problem for a plasma produced volumetrically between two planar walls. We show that all equilibrium requirements (a) floating condition, (b) plasma shielding, and (c) presheath force balance, can indeed be satisfied in two different ways when the emission coefficient γ > 1. There is one solution with SCL sheaths and one with inverse sheaths, each with sharply different presheath distributions. As we show for the first time in 1D-1V simulations, a SCL and inverse equilibrium are both possible in plasmas with the same upstream properties (e.g., same N and Te). However, maintaining a true SCL equilibrium requires no ionization or charge exchange collisions in the sheath, or else cold ion accumulation in the SCL's "dip" forces a transition to the inverse. This suggests that only a monotonic inverse type sheath potential should exist at any plasma-facing surface with strong emission, whether be a divertor plate, emissive probe, dust grain, Hall thruster channel wall, sunlit object in space, etc. Nevertheless, SCL sheaths might still be possible if the ions in the dip can escape. Our simulations demonstrate ways in which SCL and inverse regimes might be distinguished experimentally based on large-scale presheath effects, without having to probe inside the sheath.
Inverse opal with an ultraviolet photonic gap
NASA Astrophysics Data System (ADS)
Ni, Peigen; Cheng, Bingying; Zhang, Daozhong
2002-03-01
Photonic crystals composed of TiO2 and air voids fabricated by the template method exhibit an ultraviolet photonic stop band (˜380 nm) in the Γ-L direction. Scanning electron microscopy images show that the inverse opal possesses face-centered-cubic symmetry with a lattice constant of 240 nm. The transmission spectra show that the change in transmittance is one order of magnitude in the gap, which is in accord with the reflection spectrum.
Superconducting gravity gradiometer and a test of inverse square law
NASA Technical Reports Server (NTRS)
Moody, M. V.; Paik, Ho Jung
1989-01-01
The equivalence principle prohibits the distinction of gravity from acceleration by a local measurement. However, by making a differential measurement of acceleration over a baseline, platform accelerations can be cancelled and gravity gradients detected. In an in-line superconducting gravity gradiometer, this differencing is accomplished with two spring-mass accelerometers in which the proof masses are confined to motion in a single degree of freedom and are coupled together by superconducting circuits. Platform motions appear as common mode accelerations and are cancelled by adjusting the ratio of two persistent currents in the sensing circuit. The sensing circuit is connected to a commercial SQUID amplifier to sense changes in the persistent currents generated by differential accelerations, i.e., gravity gradients. A three-axis gravity gradiometer is formed by mounting six accelerometers on the faces of a precision cube, with the accelerometers on opposite faces of the cube forming one of three in-line gradiometers. A dedicated satellite mission for mapping the earth's gravity field is an important one. Additional scientific goals are a test of the inverse square law to a part in 10(exp 10) at 100 km, and a test of the Lense-Thirring effect by detecting the relativistic gravity magnetic terms in the gravity gradient tensor for the earth.
Keane, Brian P; Silverstein, Steven M; Wang, Yushi; Papathomas, Thomas V
2013-05-01
Schizophrenia patients are less susceptible to depth inversion illusions (DIIs) in which concave faces appear as convex, but what stimulus attributes generate this effect and how does it vary with clinical state? To address these issues, we had 30 schizophrenia patients and 25 well-matched healthy controls make convexity judgments on physically concave faces and scenes. Patients were selectively sampled from three levels of care to ensure symptom heterogeneity. Half of the concave objects were painted with realistic texture to enhance the convexity illusion; the remaining objects were painted uniform beige to reduce the illusion. Subjects viewed the objects with one eye while laterally moving in front of the stimulus (to see depth via motion parallax) or with two eyes while remaining motionless (to see depth stereoscopically). For each group, DIIs were stronger with texture than without, and weaker with stereoscopic information than without, indicating that patients responded normally to stimulus alterations. More importantly, patients experienced fewer illusions than controls irrespective of the face/scene category, texture, or viewing condition (parallax/stereo). Illusions became less frequent as patients experienced more positive symptoms and required more structured treatment. Taken together, these results indicate that people with schizophrenia experience fewer DIIs with a variety of object types and viewing conditions, perhaps because of a lessened tendency to construe any type of object as convex. Moreover, positive symptoms and the need for structured treatment are associated with more accurate 3-D perception, suggesting that DII may serve as a state marker for the illness. © 2013 American Psychological Association
Alcoholism and dampened temporal limbic activation to emotional faces.
Marinkovic, Ksenija; Oscar-Berman, Marlene; Urban, Trinity; O'Reilly, Cara E; Howard, Julie A; Sawyer, Kayle; Harris, Gordon J
2009-11-01
Excessive chronic drinking is accompanied by a broad spectrum of emotional changes ranging from apathy and emotional flatness to deficits in comprehending emotional information, but their neural bases are poorly understood. Emotional abnormalities associated with alcoholism were examined with functional magnetic resonance imaging in abstinent long-term alcoholic men in comparison to healthy demographically matched controls. Participants were presented with emotionally valenced words and photographs of faces during deep (semantic) and shallow (perceptual) encoding tasks followed by recognition. Overall, faces evoked stronger activation than words, with the expected material-specific laterality (left hemisphere for words, and right for faces) and depth of processing effects. However, whereas control participants showed stronger activation in the amygdala and hippocampus when viewing faces with emotional (relative to neutral) expressions, the alcoholics responded in an undifferentiated manner to all facial expressions. In the alcoholic participants, amygdala activity was inversely correlated with an increase in lateral prefrontal activity as a function of their behavioral deficits. Prefrontal modulation of emotional function as a compensation for the blunted amygdala activity during a socially relevant face appraisal task is in agreement with a distributed network engagement during emotional face processing. Deficient activation of amygdala and hippocampus may underlie impaired processing of emotional faces associated with long-term alcoholism and may be a part of the wide array of behavioral problems including disinhibition, concurring with previously documented interpersonal difficulties in this population. Furthermore, the results suggest that alcoholics may rely on prefrontal rather than temporal limbic areas in order to compensate for reduced limbic responsivity and to maintain behavioral adequacy when faced with emotionally or socially challenging situations.
Affect and neural activity in women with PTSD during a task of emotional interference.
Brown, Wilson J; Wojtalik, Jessica A; Dewey, Daniel; Bruce, Steven E; Yang, Zhen; Sheline, Yvette I
2016-11-01
The current study sought to determine the relationship between self-reported dimensions of affect and activation in brain regions associated with emotion regulation in PTSD during a task of non-conscious emotional processing in interpersonal trauma survivors with PTSD and healthy controls. Participants included 52 women diagnosed with PTSD and 18 female healthy controls. All participants completed a clinical assessment including the SCID, CAPS, and PANAS followed by a functional MRI assessment including a task of implicit emotional conflict. When PTSD participants were oriented to fearful faces, negative affect (NA) was inversely related to activation in the left amygdala and positive affect (PA) was inversely related to activation in the right amygdala. When ignoring fearful faces, NA was positively associated with activation in the right parahippocampal gyrus and PA was inversely related to activation in the left hippocampus. Similar results were observed in healthy controls regarding PA. However, NA was not significantly related to any region of interest in healthy controls. Limitations include the homogeneity of the healthy controls with regard to racial diversity, results may only be specific to female interpersonal trauma survivors with PTSD, and neutral faces within the conflict task may be perceived as negative by clinical samples. Persistent, increased NA may represent a proxy for disruptions in emotional processing in interpersonal trauma survivors with PTSD. As such, clinicians may prioritize increasing emotional awareness through emotion regulation and/or distress tolerance strategies in this population. Copyright © 2016 Elsevier B.V. All rights reserved.
Arizpe, Joseph; Kravitz, Dwight J.; Yovel, Galit; Baker, Chris I.
2012-01-01
Fixation patterns are thought to reflect cognitive processing and, thus, index the most informative stimulus features for task performance. During face recognition, initial fixations to the center of the nose have been taken to indicate this location is optimal for information extraction. However, the use of fixations as a marker for information use rests on the assumption that fixation patterns are predominantly determined by stimulus and task, despite the fact that fixations are also influenced by visuo-motor factors. Here, we tested the effect of starting position on fixation patterns during a face recognition task with upright and inverted faces. While we observed differences in fixations between upright and inverted faces, likely reflecting differences in cognitive processing, there was also a strong effect of start position. Over the first five saccades, fixation patterns across start positions were only coarsely similar, with most fixations around the eyes. Importantly, however, the precise fixation pattern was highly dependent on start position with a strong tendency toward facial features furthest from the start position. For example, the often-reported tendency toward the left over right eye was reversed for the left starting position. Further, delayed initial saccades for central versus peripheral start positions suggest greater information processing prior to the initial saccade, highlighting the experimental bias introduced by the commonly used center start position. Finally, the precise effect of face inversion on fixation patterns was also dependent on start position. These results demonstrate the importance of a non-stimulus, non-task factor in determining fixation patterns. The patterns observed likely reflect a complex combination of visuo-motor effects and simple sampling strategies as well as cognitive factors. These different factors are very difficult to tease apart and therefore great caution must be applied when interpreting absolute fixation locations as indicative of information use, particularly at a fine spatial scale. PMID:22319606
De Donno, Giorgio; Cardarelli, Ettore
2017-01-01
In this paper, we present a new code for the modelling and inversion of resistivity and chargeability data using a priori information to improve the accuracy of the reconstructed model for landfill. When a priori information is available in the study area, we can insert them by means of inequality constraints on the whole model or on a single layer or assigning weighting factors for enhancing anomalies elongated in the horizontal or vertical directions. However, when we have to face a multilayered scenario with numerous resistive to conductive transitions (the case of controlled landfills), the effective thickness of the layers can be biased. The presented code includes a model-tuning scheme, which is applied after the inversion of field data, where the inversion of the synthetic data is performed based on an initial guess, and the absolute difference between the field and synthetic inverted models is minimized. The reliability of the proposed approach has been supported in two real-world examples; we were able to identify an unauthorized landfill and to reconstruct the geometrical and physical layout of an old waste dump. The combined analysis of the resistivity and chargeability (normalised) models help us to remove ambiguity due to the presence of the waste mass. Nevertheless, the presence of certain layers can remain hidden without using a priori information, as demonstrated by a comparison of the constrained inversion with a standard inversion. The robustness of the above-cited method (using a priori information in combination with model tuning) has been validated with the cross-section from the construction plans, where the reconstructed model is in agreement with the original design. Copyright © 2016 Elsevier Ltd. All rights reserved.
Are two plasma equilibrium states possible when the emission coefficient exceeds unity?
Campanell, Michael D.; Umansky, M. V.
2017-02-28
Two floating sheath solutions with strong electron emission in planar geometry have been proposed, a “space-charge limited” (SCL) sheath and an “inverse” sheath. SCL and inverse models contain different assumptions about conditions outside the sheath (e.g., the velocity of ions entering the sheath). So it is not yet clear whether both sheaths are possible in practice, or only one. Here we treat the global presheath-sheath problem for a plasma produced volumetrically between two planar walls. We show that all equilibrium requirements (a) floating condition, (b) plasma shielding, and (c) presheath force balance, can indeed be satisfied in two different waysmore » when the emission coefficient γ > 1. There is one solution with SCL sheaths and one with inverse sheaths, each with sharply different presheath distributions. As we show for the first time in 1D-1V simulations, a SCL and inverse equilibrium are both possible in plasmas with the same upstream properties (e.g., same N and Te). However, maintaining a true SCL equilibrium requires no ionization or charge exchange collisions in the sheath, or else cold ion accumulation in the SCL's “dip” forces a transition to the inverse. This suggests that only a monotonic inverse type sheath potential should exist at any plasma-facing surface with strong emission, whether be a divertor plate, emissive probe, dust grain, Hall thruster channel wall, sunlit object in space, etc. Nevertheless, SCL sheaths might still be possible if the ions in the dip can escape. Finally, our simulations demonstrate ways in which SCL and inverse regimes might be distinguished experimentally based on large-scale presheath effects, without having to probe inside the sheath.« less
Periodic order and defects in Ni-based inverse opal-like crystals on the mesoscopic and atomic scale
NASA Astrophysics Data System (ADS)
Chumakova, A. V.; Valkovskiy, G. A.; Mistonov, A. A.; Dyadkin, V. A.; Grigoryeva, N. A.; Sapoletova, N. A.; Napolskii, K. S.; Eliseev, A. A.; Petukhov, A. V.; Grigoriev, S. V.
2014-10-01
The structure of inverse opal crystals based on nickel was probed on the mesoscopic and atomic levels by a set of complementary techniques such as scanning electron microscopy and synchrotron microradian and wide-angle diffraction. The microradian diffraction revealed the mesoscopic-scale face-centered-cubic (fcc) ordering of spherical voids in the inverse opal-like structure with unit cell dimension of 750±10nm. The diffuse scattering data were used to map defects in the fcc structure as a function of the number of layers in the Ni inverse opal-like structure. The average lateral size of mesoscopic domains is found to be independent of the number of layers. 3D reconstruction of the reciprocal space for the inverse opal crystals with different thickness provided an indirect study of original opal templates in a depth-resolved way. The microstructure and thermal response of the framework of the porous inverse opal crystal was examined using wide-angle powder x-ray diffraction. This artificial porous structure is built from nickel crystallites possessing stacking faults and dislocations peculiar for the nickel thin films.
Characterizing the impact of model error in hydrologic time series recovery inverse problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hansen, Scott K.; He, Jiachuan; Vesselinov, Velimir V.
Hydrologic models are commonly over-smoothed relative to reality, owing to computational limitations and to the difficulty of obtaining accurate high-resolution information. When used in an inversion context, such models may introduce systematic biases which cannot be encapsulated by an unbiased “observation noise” term of the type assumed by standard regularization theory and typical Bayesian formulations. Despite its importance, model error is difficult to encapsulate systematically and is often neglected. In this paper, model error is considered for an important class of inverse problems that includes interpretation of hydraulic transients and contaminant source history inference: reconstruction of a time series thatmore » has been convolved against a transfer function (i.e., impulse response) that is only approximately known. Using established harmonic theory along with two results established here regarding triangular Toeplitz matrices, upper and lower error bounds are derived for the effect of systematic model error on time series recovery for both well-determined and over-determined inverse problems. It is seen that use of additional measurement locations does not improve expected performance in the face of model error. A Monte Carlo study of a realistic hydraulic reconstruction problem is presented, and the lower error bound is seen informative about expected behavior. Finally, a possible diagnostic criterion for blind transfer function characterization is also uncovered.« less
Characterizing the impact of model error in hydrologic time series recovery inverse problems
Hansen, Scott K.; He, Jiachuan; Vesselinov, Velimir V.
2017-10-28
Hydrologic models are commonly over-smoothed relative to reality, owing to computational limitations and to the difficulty of obtaining accurate high-resolution information. When used in an inversion context, such models may introduce systematic biases which cannot be encapsulated by an unbiased “observation noise” term of the type assumed by standard regularization theory and typical Bayesian formulations. Despite its importance, model error is difficult to encapsulate systematically and is often neglected. In this paper, model error is considered for an important class of inverse problems that includes interpretation of hydraulic transients and contaminant source history inference: reconstruction of a time series thatmore » has been convolved against a transfer function (i.e., impulse response) that is only approximately known. Using established harmonic theory along with two results established here regarding triangular Toeplitz matrices, upper and lower error bounds are derived for the effect of systematic model error on time series recovery for both well-determined and over-determined inverse problems. It is seen that use of additional measurement locations does not improve expected performance in the face of model error. A Monte Carlo study of a realistic hydraulic reconstruction problem is presented, and the lower error bound is seen informative about expected behavior. Finally, a possible diagnostic criterion for blind transfer function characterization is also uncovered.« less
Prete, Giulia; Capotosto, Paolo; Zappasodi, Filippo; Laeng, Bruno; Tommasi, Luca
2015-12-01
In a high-resolution electroencephalographic study, participants evaluated the friendliness level of upright and inverted 'hybrid faces', i.e. facial photos containing a subliminal emotional core in the low spatial frequencies (< 6 cycles/image), superimposed on a neutral expression in the rest of the spatial frequencies. Upright happy and angry faces were judged as more friendly or less friendly than neutral faces, respectively. We observed the time course of cerebral correlates of these stimuli with event-related potentials (ERPs), confirming that hybrid faces elicited the posterior emotion-related and face-related components (P1, N170 and P2), previously shown to be engaged by non-subliminal emotional stimuli. In addition, these components were stronger in the right hemisphere and were both enhanced and delayed by face inversion. A frontal positivity (210-300 ms) was stronger for emotional than for neutral faces, and for upright than for inverted faces. Hence, hybrid faces represent an original approach in the study of subliminal emotions, which appears promising for investigating their electrophysiological correlates. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
Alcoholism and Dampened Temporal Limbic Activation to Emotional Faces
Marinkovic, Ksenija; Oscar-Berman, Marlene; Urban, Trinity; O’Reilly, Cara E.; Howard, Julie A.; Sawyer, Kayle; Harris, Gordon J.
2013-01-01
Background Excessive chronic drinking is accompanied by a broad spectrum of emotional changes ranging from apathy and emotional flatness to deficits in comprehending emotional information, but their neural bases are poorly understood. Methods Emotional abnormalities associated with alcoholism were examined with functional magnetic resonance imaging in abstinent long-term alcoholic men in comparison to healthy demographically matched controls. Participants were presented with emotionally valenced words and photographs of faces during deep (semantic) and shallow (perceptual) encoding tasks followed by recognition. Results Overall, faces evoked stronger activation than words, with the expected material-specific laterality (left hemisphere for words, and right for faces) and depth of processing effects. However, whereas control participants showed stronger activation in the amygdala and hippocampus when viewing faces with emotional (relative to neutral) expressions, the alcoholics responded in an undifferentiated manner to all facial expressions. In the alcoholic participants, amygdala activity was inversely correlated with an increase in lateral prefrontal activity as a function of their behavioral deficits. Prefrontal modulation of emotional function as a compensation for the blunted amygdala activity during a socially relevant face appraisal task is in agreement with a distributed network engagement during emotional face processing. Conclusions Deficient activation of amygdala and hippocampus may underlie impaired processing of emotional faces associated with long-term alcoholism and may be a part of the wide array of behavioral problems including disinhibition, concurring with previously documented interpersonal difficulties in this population. Furthermore, the results suggest that alcoholics may rely on prefrontal rather than temporal limbic areas in order to compensate for reduced limbic responsivity and to maintain behavioral adequacy when faced with emotionally or socially challenging situations. PMID:19673745
Graewe, Britta; De Weerd, Peter; Farivar, Reza; Castelo-Branco, Miguel
2012-01-01
Many studies have linked the processing of different object categories to specific event-related potentials (ERPs) such as the face-specific N170. Despite reports showing that object-related ERPs are influenced by visual stimulus features, there is consensus that these components primarily reflect categorical aspects of the stimuli. Here, we re-investigated this idea by systematically measuring the effects of visual feature manipulations on ERP responses elicited by both structure-from-motion (SFM)-defined and luminance-defined object stimuli. SFM objects elicited a novel component at 200–250 ms (N250) over parietal and posterior temporal sites. We found, however, that the N250 amplitude was unaffected by restructuring SFM stimuli into meaningless objects based on identical visual cues. This suggests that this N250 peak was not uniquely linked to categorical aspects of the objects, but is strongly determined by visual stimulus features. We provide strong support for this hypothesis by parametrically manipulating the depth range of both SFM- and luminance-defined object stimuli and showing that the N250 evoked by SFM stimuli as well as the well-known N170 to static faces were sensitive to this manipulation. Importantly, this effect could not be attributed to compromised object categorization in low depth stimuli, confirming a strong impact of visual stimulus features on object-related ERP signals. As ERP components linked with visual categorical object perception are likely determined by multiple stimulus features, this creates an interesting inverse problem when deriving specific perceptual processes from variations in ERP components. PMID:22363479
Graewe, Britta; De Weerd, Peter; Farivar, Reza; Castelo-Branco, Miguel
2012-01-01
Many studies have linked the processing of different object categories to specific event-related potentials (ERPs) such as the face-specific N170. Despite reports showing that object-related ERPs are influenced by visual stimulus features, there is consensus that these components primarily reflect categorical aspects of the stimuli. Here, we re-investigated this idea by systematically measuring the effects of visual feature manipulations on ERP responses elicited by both structure-from-motion (SFM)-defined and luminance-defined object stimuli. SFM objects elicited a novel component at 200-250 ms (N250) over parietal and posterior temporal sites. We found, however, that the N250 amplitude was unaffected by restructuring SFM stimuli into meaningless objects based on identical visual cues. This suggests that this N250 peak was not uniquely linked to categorical aspects of the objects, but is strongly determined by visual stimulus features. We provide strong support for this hypothesis by parametrically manipulating the depth range of both SFM- and luminance-defined object stimuli and showing that the N250 evoked by SFM stimuli as well as the well-known N170 to static faces were sensitive to this manipulation. Importantly, this effect could not be attributed to compromised object categorization in low depth stimuli, confirming a strong impact of visual stimulus features on object-related ERP signals. As ERP components linked with visual categorical object perception are likely determined by multiple stimulus features, this creates an interesting inverse problem when deriving specific perceptual processes from variations in ERP components.
Freezing of soft spheres: A critical test for weighted-density-functional theories
NASA Astrophysics Data System (ADS)
Laird, Brian B.; Kroll, D. M.
1990-10-01
We study the freezing properties of systems with inverse-power and Yukawa interactions (soft spheres), using recently developed weighted-density-functional theories. We find that the modified weighted-density-functional approximation (MWDA) of Denton and Ashcroft yields results for the liquid to face-centered-cubic (fcc) structure transition that represent a significant improvement over those of earlier ``second-order'' density-functional freezing theories; however, this theory, like the earlier ones, fails to predict any liquid to body-centered-cubic (bcc) transition, even under conditions where the computer simulations indicate that this should be the equilibrium solid structure. In addition, we show that both the modified effective-liquid approximation (MELA) of Baus [J. Phys. Condens. Matter 2, 2111 (1990)] and the generalized effective-liquid approximation of Lutsko and Baus [Phys. Rev. Lett. 64, 761 (1990)], while giving excellent results for the freezing of hard spheres, fail completely to predict freezing into either fcc or bcc solid phases for soft inverse-power potentials. We also give an alternate derivation of the MWDA that makes clearer its connection to earlier theories.
Thirioux, Bérangère; Wehrmann, Moritz; Langbour, Nicolas; Jaafari, Nematollah; Berthoz, Alain
2016-01-01
Looking at our face in a mirror is one of the strongest phenomenological experiences of the Self in which we need to identify the face as reflected in the mirror as belonging to us. Recent behavioral and neuroimaging studies reported that self-face identification not only relies upon visual-mnemonic representation of one’s own face but also upon continuous updating and integration of visuo-tactile signals. Therefore, bodily self-consciousness plays a major role in self-face identification, with respect to interplay between unisensory and multisensory processing. However, if previous studies demonstrated that the integration of multisensory body-related signals contributes to the visual processing of one’s own face, there is so far no data regarding how self-face identification, inversely, contributes to bodily self-consciousness. In the present study, we tested whether self–other face identification impacts either the egocentered or heterocentered visuo-spatial mechanisms that are core processes of bodily self-consciousness and sustain self–other distinction. For that, we developed a new paradigm, named “Double Mirror.” This paradigm, consisting of a semi-transparent double mirror and computer-controlled Light Emitting Diodes, elicits self–other face merging illusory effect in ecologically more valid conditions, i.e., when participants are physically facing each other and interacting. Self-face identification was manipulated by exposing pairs of participants to an Interpersonal Visual Stimulation in which the reflection of their faces merged in the mirror. Participants simultaneously performed visuo-spatial and mental own-body transformation tasks centered on their own face (egocentered) or the face of their partner (heterocentered) in the pre- and post-stimulation phase. We show that self–other face identification altered the egocentered visuo-spatial mechanisms. Heterocentered coding was preserved. Our data suggest that changes in self-face identification induced a bottom-up conflict between the current visual representation and the stored mnemonic representation of one’s own face which, in turn, top-down impacted bodily self-consciousness. PMID:27610095
Magnetic topology of Co-based inverse opal-like structures
NASA Astrophysics Data System (ADS)
Grigoryeva, N. A.; Mistonov, A. A.; Napolskii, K. S.; Sapoletova, N. A.; Eliseev, A. A.; Bouwman, W.; Byelov, D. V.; Petukhov, A. V.; Chernyshov, D. Yu.; Eckerlebe, H.; Vasilieva, A. V.; Grigoriev, S. V.
2011-08-01
The magnetic and structural properties of a cobalt inverse opal-like crystal have been studied by a combination of complementary techniques ranging from polarized neutron scattering and superconducting quantum interference device (SQUID) magnetometry to x-ray diffraction. Microradian small-angle x-ray diffraction shows that the inverse opal-like structure (OLS) synthesized by the electrochemical method fully duplicates the three-dimensional net of voids of the template artificial opal. The inverse OLS has a face-centered cubic (fcc) structure with a lattice constant of 640±10 nm and with a clear tendency to a random hexagonal close-packed structure along the [111] axes. Wide-angle x-ray powder diffraction shows that the atomic cobalt structure is described by coexistence of 95% hexagonal close-packed and 5% fcc phases. The SQUID measurements demonstrate that the inverse OLS film possesses easy-plane magnetization geometry with a coercive field of 14.0 ± 0.5 mT at room temperature. The detailed picture of the transformation of the magnetic structure under an in-plane applied field was detected with the help of small-angle diffraction of polarized neutrons. In the demagnetized state the magnetic system consists of randomly oriented magnetic domains. A complex magnetic structure appears upon application of the magnetic field, with nonhomogeneous distribution of magnetization density within the unit element of the OLS. This distribution is determined by the combined effect of the easy-plane geometry of the film and the crystallographic geometry of the opal-like structure with respect to the applied field direction.
Fantauzzo, Katherine A.; Tadin-Strapps, Marija; You, Yun; Mentzer, Sarah E.; Baumeister, Friedrich A.M.; Cianfarani, Stefano; Van Maldergem, Lionel; Warburton, Dorothy; Sundberg, John P.; Christiano, Angela M.
2008-01-01
Ambras syndrome (AS) is a rare form of congenital hypertrichosis with excessive hair on the shoulders, face and ears. Cytogenetic studies have previously implicated an association with rearrangements of chromosome 8. Here we define an 11.5 Mb candidate interval for AS on chromosome 8q based on cytogenetic breakpoints in three patients. TRPS1, a gene within this interval, was deleted in a patient with an 8q23 chromosomal rearrangement, while its expression was significantly downregulated in another patient with an inversion breakpoint 7.3 Mb downstream of TRPS1. Here, we describe the first potential long-range position effect on the expression of TRPS1. To gain insight into the mechanisms by which Trps1 affects the hair follicle, we performed a detailed analysis of the hair abnormalities in Koa mice, a mouse model of hypertrichosis. We found that the proximal breakpoint of the Koa inversion is located 791 kb upstream of Trps1. Quantitative real-time polymerase chain reaction, in situ hybridization and immunofluorescence analysis revealed that Trps1 expression levels are reduced in Koa mutant mice at the sites of pathology for the phenotype. We determined that the Koa inversion creates a new Sp1 binding site and translocates additional Sp1 binding sites within a highly conserved stretch spanning the proximal breakpoint, providing a potential mechanism for the position effect. Collectively, these results describe a position effect that downregulates TRPS1 expression as the probable cause of hypertrichosis in AS in humans and the Koa phenotype in mice. PMID:18713754
Face Centered Cubic SnSe as a Z2 Trivial Dirac Nodal Line Material
NASA Astrophysics Data System (ADS)
Tateishi, Ikuma; Matsuura, Hiroyasu
2018-07-01
The presence of a Dirac nodal line in a time-reversal and inversion symmetric system is dictated by the Z2 index when spin-orbit interaction is absent. In a first principles calculation, we show that a Dirac nodal line can emerge in Z2 trivial material by calculating the band structure of SnSe in a face centered cubic lattice as an example. We qualitatively show that it becomes a topological crystalline insulator when spin-orbit interaction is taken into account. We clarify the origin of the Dirac nodal line by obtaining irreducible representations corresponding to bands and explain the triviality of the Z2 index. We construct an effective model representing the Dirac nodal line using the k · p method, and discuss the Berry phase and a surface state expected from the Dirac nodal line.
NASA Astrophysics Data System (ADS)
Raefat, Saad; Garoum, Mohammed; Laaroussi, Najma; Thiam, Macodou; Amarray, Khaoula
2017-07-01
In this work experimental investigation of apparent thermal diffusivity and adiabatic limit temperature of expanded granular perlite mixes has been made using the flash technic. Perlite granulates were sieved to produce essentially three characteristic grain sizes. The consolidated samples were manufactured by mixing controlled proportions of the plaster and water. The effect of the particle size on the diffusivity was examined. The inverse estimation of the diffusivity and the adiabatic limit temperature at the rear face as well as the heat losses coefficients were performed using several numerical global minimization procedures. The function to be minimized is the quadratic distance between the experimental temperature rise at the rear face and the analytical model derived from the one dimension heat conduction. It is shown that, for all granulometry tested, the estimated parameters lead to a good agreement between the mathematical model and experimental data.
Spontaneous Water Oxidation at Hematite (α-Fe2O3) Crystal Faces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chatman, Shawn ME; Zarzycki, Piotr P.; Rosso, Kevin M.
2015-01-28
Hematite (α-Fe2O3) persists as a promising candidate for photoelectrochemical water splitting but a slow oxygen evolution reaction (OER) at its surfaces remains a limitation. Here we extend a series of studies that examine pH-dependent surface potentials and electron transfer properties of effectively perfect low-index crystal faces of hematite in contact with simple electrolyte. Zero resistance amperometry was performed in a two electrode configuration to quantify spontaneous dark current between hematite crystal face pairs (001)/(012), (001)/(113), and (012)/(113) at pH 3. Exponentially decaying currents initially of up to 200 nA were reported between faces over four minute experiments. Fourth order ZRAmore » kinetics indicated rate limitation by the OER for current that flows between (001)/(012) and (001)/(113) face pairs, with the (012) and (113) faces serving as the anodes when paired with (001). The cathodic partner reaction is reductive dissolution of the (001) face, converting surface Fe3+ to solubilized aqueous Fe2+, at a rate maintained by the OER at the anode. In contrast, OER rate limitation does not manifest for the (012)/(113) pair. The uniqueness of the (001) face is established in terms of a faster intrinsic ability to accept the protons required for the reductive dissolution reaction. OER rate limitation inversely may thus arise from sluggish kinetics of hematite surfaces to dispense with the protons that accompany the four-electron OER. The results are explained in terms of semi-quantitative energy band diagrams. The finding may be useful as a consideration for tailoring the design of polycrystalline hematite photoanodes that present multiple terminations to the interface with electrolyte.« less
Multiparameter elastic full waveform inversion with facies-based constraints
NASA Astrophysics Data System (ADS)
Zhang, Zhen-dong; Alkhalifah, Tariq; Naeini, Ehsan Zabihi; Sun, Bingbing
2018-06-01
Full waveform inversion (FWI) incorporates all the data characteristics to estimate the parameters described by the assumed physics of the subsurface. However, current efforts to utilize FWI beyond improved acoustic imaging, like in reservoir delineation, faces inherent challenges related to the limited resolution and the potential trade-off between the elastic model parameters. Some anisotropic parameters are insufficiently updated because of their minor contributions to the surface collected data. Adding rock physics constraints to the inversion helps mitigate such limited sensitivity, but current approaches to add such constraints are based on including them as a priori knowledge mostly valid around the well or as a global constraint for the whole area. Since similar rock formations inside the Earth admit consistent elastic properties and relative values of elasticity and anisotropy parameters (this enables us to define them as a seismic facies), utilizing such localized facies information in FWI can improve the resolution of inverted parameters. We propose a novel approach to use facies-based constraints in both isotropic and anisotropic elastic FWI. We invert for such facies using Bayesian theory and update them at each iteration of the inversion using both the inverted models and a priori information. We take the uncertainties of the estimated parameters (approximated by radiation patterns) into consideration and improve the quality of estimated facies maps. Four numerical examples corresponding to different acquisition, physical assumptions and model circumstances are used to verify the effectiveness of the proposed method.
A fast multigrid-based electromagnetic eigensolver for curved metal boundaries on the Yee mesh
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bauer, Carl A., E-mail: carl.bauer@colorado.edu; Werner, Gregory R.; Cary, John R.
For embedded boundary electromagnetics using the Dey–Mittra (Dey and Mittra, 1997) [1] algorithm, a special grad–div matrix constructed in this work allows use of multigrid methods for efficient inversion of Maxwell’s curl–curl matrix. Efficient curl–curl inversions are demonstrated within a shift-and-invert Krylov-subspace eigensolver (open-sourced at ([ofortt]https://github.com/bauerca/maxwell[cfortt])) on the spherical cavity and the 9-cell TESLA superconducting accelerator cavity. The accuracy of the Dey–Mittra algorithm is also examined: frequencies converge with second-order error, and surface fields are found to converge with nearly second-order error. In agreement with previous work (Nieter et al., 2009) [2], neglecting some boundary-cut cell faces (as is requiredmore » in the time domain for numerical stability) reduces frequency convergence to first-order and surface-field convergence to zeroth-order (i.e. surface fields do not converge). Additionally and importantly, neglecting faces can reduce accuracy by an order of magnitude at low resolutions.« less
Barriers to providing the sexuality education that teachers believe students need.
Eisenberg, Marla E; Madsen, Nikki; Oliphant, Jennifer A; Sieving, Renee E
2013-05-01
Sexuality education teachers' perspectives are important to gain a full understanding of the issues surrounding teaching this subject. This study uses a statewide sample of public school teachers to examine what sexuality education content is taught, what barriers teachers face, and which barriers are associated with teaching specific topics. Participants included 368 middle and high school teachers with sexuality education assignments in Minnesota. Survey data included topics they teach, what they think they should teach, and barriers they face. Logistic regression was used to examine associations between barriers and teaching each of 9 sexual health topics, among those who believed the topic should be taught. Almost two thirds of participants faced structural barriers; 45% were concerned about parent, student, or administrator response; and one quarter reported restrictive policies. Structural barriers were inversely associated with teaching about communication (OR = 0.20), teen parenting (OR = 0.34), and abortion (OR = 0.32); concerns about responses were associated only with teaching about sexual violence (OR = 0.42); and restrictive policies were inversely associated with teaching about abortion (OR = 0.23) and sexual orientation (OR = 0.47). Addressing teachers' barriers requires a multipronged approach, including curriculum development and evaluation, training, and reframing the policy debate to support a wider range of sexuality education topics. © 2013, American School Health Association.
Kinematical synthesis of an inversion of the double linked fourbar for morphing wing applications
NASA Astrophysics Data System (ADS)
Aguirrebeitia, J.; Avilés, R.; Fernández, I.; Abasolo, M.
2013-03-01
This paper presents the kinematical features of an inversion of the double linked fourbar for morphing wing purposes. The structure of the mechanism is obtained using structural synthesis concepts, from an initial conceptual schematic. Then, kinematic characteristics as instant center of rotation, lock positions, dead point positions and uncertainty positions are derived for this mechanism in order to face the last step, the dimensional synthesis; in this sense, two kinds of dimensional synthesis are arranged to guide the wing along two positions, and to fulfill with the second one some aerodynamic and minimum actuation energy related issues.
Broadband focusing ultrasonic transducers based on dimpled LiNbO3 plate with inversion layer.
Chen, Jin; Dai, Ji-Yan; Zhang, Chao; Zhang, Zhitian; Feng, Guanping
2012-12-01
A high-frequency broadband focusing transducer based on dimpled LiNbO(3) inversion layer plate has been fabricated and characterized. A spherical surface with a curvature radius of 6 mm is formed on the half-thickness LiNbO(3) inversion layer plate of Y36° cut orientation. The domain structure in the cross section is observed after a hydrofluoric acid etching process. For transducer fabrication, conductive epoxy is used as the backing material and polymer is deposited on the front face as the matching layer. The center frequency, bandwidth, and insertion loss of the focused transducer are measured to be 72 MHz, 136%, and -32 dB, respectively. The focused transducer has been successfully used for rabbit eyeball imaging and a better imaging capability compared with the planar transducer has been demonstrated. These promising results prove that the dimpled LiNbO(3) inversion layer plate has great potential for fabrication of high-frequency broadband focusing ultrasonic transducers.
Quality of life in schizophrenia spectrum disorders: associations with insight and psychopathology.
Margariti, Maria; Ploumpidis, Dimitris; Economou, Marina; Christodoulou, George N; Papadimitriou, George N
2015-02-28
Therapeutic interventions in chronic mental illness face the important challenge to pursuit the quality of life (QOL) of patients. Insight into chronic mental illness, though a prerequisite for treatment adherence and a positive therapeutic outcome, has shown adverse associations with subjective QOL. This study aims to explore the contribution of psychopathological symptoms on the ambiguous role of insight on QOL. Seventy-two outpatients with schizophrenia spectrum disorders were assessed using the positive and negative syndrome scale, the scale to assess unawareness of mental disorder, and the WHOQOL-100 instrument for the assessment of quality of life. Insight was found to associate inversely with quality of life. Among psychopathological symptoms, depressive symptoms were the strongest negative contributor on QOL. Mediation analysis revealed that the effects of awareness of the consequences of illness on QOL were largely mediated by depressive symptoms (full mediation for the effect on physical and psychological domain and partial mediation for the effect on independence and environment domain of the QOL). Our results suggest that the inverse relationship between insight and subjective quality of life is partially mediated by depressive symptoms. We discuss theoretical and therapeutic implications of the findings, in conjunction with similar recent research data. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Solving geosteering inverse problems by stochastic Hybrid Monte Carlo method
Shen, Qiuyang; Wu, Xuqing; Chen, Jiefu; ...
2017-11-20
The inverse problems arise in almost all fields of science where the real-world parameters are extracted from a set of measured data. The geosteering inversion plays an essential role in the accurate prediction of oncoming strata as well as a reliable guidance to adjust the borehole position on the fly to reach one or more geological targets. This mathematical treatment is not easy to solve, which requires finding an optimum solution among a large solution space, especially when the problem is non-linear and non-convex. Nowadays, a new generation of logging-while-drilling (LWD) tools has emerged on the market. The so-called azimuthalmore » resistivity LWD tools have azimuthal sensitivity and a large depth of investigation. Hence, the associated inverse problems become much more difficult since the earth model to be inverted will have more detailed structures. The conventional deterministic methods are incapable to solve such a complicated inverse problem, where they suffer from the local minimum trap. Alternatively, stochastic optimizations are in general better at finding global optimal solutions and handling uncertainty quantification. In this article, we investigate the Hybrid Monte Carlo (HMC) based statistical inversion approach and suggest that HMC based inference is more efficient in dealing with the increased complexity and uncertainty faced by the geosteering problems.« less
Ahmed, Lubna
2018-03-01
The ability to correctly interpret facial expressions is key to effective social interactions. People are well rehearsed and generally very efficient at correctly categorizing expressions. However, does their ability to do so depend on how cognitively loaded they are at the time? Using repeated-measures designs, we assessed the sensitivity of facial expression categorization to cognitive resources availability by measuring people's expression categorization performance during concurrent low and high cognitive load situations. In Experiment1, participants categorized the 6 basic upright facial expressions in a 6-automated-facial-coding response paradigm while maintaining low or high loading information in working memory (N = 40; 60 observations per load condition). In Experiment 2, they did so for both upright and inverted faces (N = 46; 60 observations per load and inversion condition). In both experiments, expression categorization for upright faces was worse during high versus low load. Categorization rates actually improved with increased load for the inverted faces. The opposing effects of cognitive load on upright and inverted expressions are explained in terms of a cognitive load-related dispersion in the attentional window. Overall, the findings support that expression categorization is sensitive to cognitive resources availability and moreover suggest that, in this paradigm, it is the perceptual processing stage of expression categorization that is affected by cognitive load. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Xu, Wang Hong; Zheng, Wei; Xiang, Yong Bing; Ruan, Zhi Xian; Cheng, Jia Rong; Dai, Qi; Gao, Yu Tang; Shu, Xiao Ou
2004-01-01
Objective To evaluate the association of intake of soya food, a rich source of phytoestrogens, with the risk of endometrial cancer. Design Population based case-control study, with detailed information on usual soya food intake over the past five years collected by face to face interview using a food frequency questionnaire. Setting Urban Shanghai, China. Participants 832 incident cases of endometrial cancer in women aged of 30 to 69 years diagnosed during 1997-2001 and identified from the Shanghai Cancer Registry; 846 control women frequency matched to cases on age and randomly selected from the Shanghai Residential Registry. Main outcome measures Odds ratios for risk of endometrial cancer in women with different intakes of soya foods. Results Regular consumption of soya foods, measured as amount of either soya protein or soya isoflavones, was inversely associated with the risk of endometrial cancer. Compared with women with the lowest quarter of intake, the adjusted odds ratio of endometrial cancer was reduced from 0.93 to 0.85 and 0.67 with increasing quarter of soya protein intake (P for trend 0.01). A similar inverse association was observed for soya isoflavones and soya fibre intake. The inverse association seemed to be more pronounced among women with high body mass index and waist:hip ratio. Conclusion Regular intake of soya foods is associated with a reduced risk of endometrial cancer. PMID:15136343
The Two Faces of Sulfinates: Illustrating Umpolung Reactivity
ERIC Educational Resources Information Center
Tapia-Pineda, Adabelia; Perez-Arrieta, Carlos; Silva-Cuevas, Carolina; Paleo, Ehecatl; Lujan-Montelongo, J. Armando
2016-01-01
A simple, microscale experiment was developed with the aim of demonstrating the concept of umpolung in synthetic organic chemistry. Starting from a common alkyl sulfinate, students perform a polarity inversion by performing a Grignard-based sulfoxide synthesis and a Mannich-type formamide synthesis. The products are purified without chromatography…
Zhang, Cai-Xia; Pan, Mei-Xia; Li, Bin; Wang, Lian; Mo, Xiong-Fei; Chen, Yu-Ming; Lin, Fang-Yu; Ho, Suzanne C
2013-02-01
Few epidemiological studies have evaluated the association of choline and betaine intake with breast cancer risk and the results remain inconsistent. This study aimed to assess the relationship between dietary intake of choline and betaine and the risk of breast cancer among Chinese women. A two-stage case-control study was conducted, with 807 cases and 807 age- (5-year interval) and residence (rural/urban)-matched controls. A validated food frequency questionnaire was used to assess dietary intake by face-to-face interview. An unconditional logistic regression model was used to calculate multivariate-adjusted odds ratios (OR) and 95% confidence intervals (CI). A significant inverse association was found between dietary choline and betaine consumption and breast cancer risk. The adjusted OR for the highest quartile of intake compared with the lowest were 0.40 (95% CI = 0.28-0.57, P(trend) < 0.001) for total choline intake, 0.58 (95% CI = 0.42-0.80, P(trend) < 0.001) for betaine intake and 0.38 (0.27-0.53, P(trend) < 0.001) for choline plus betaine intake, respectively. Intakes of individual choline compouds, choline from glycerophosphocholine, phosphocholine, phosphatidylcholine, sphingomyelin and free choline were also negatively associated with breast cancer risk. The inverse association between choline intake and breast cancer risk was primarily confined to participants with low folate level (<242 g/day), with an OR (95% CI) of 0.46 (0.23-0.91) comparing the fourth quartile with the first quartile of choline intake (P(trend) = 0.005). The present study suggests that consumption of choline and betaine is inversely associated with the risk of breast cancer. The association of choline intake with breast cancer risk is probably modified by folate intake. © 2012 Japanese Cancer Association.
Smoking, genes encoding dopamine pathway and risk for Parkinson's disease.
Gu, Zhuqin; Feng, Xiuli; Dong, Xiumin; Chan, Piu
2010-09-20
Smoking has been reported to be inversely associated with Parkinson's disease (PD) in many studies, but a recent study in China found that smoking increased the risk of PD. Variants in genes associated with dopamine metabolism found to increase the risk for PD have also been associated with smoking behavior. To investigate the association between smoking and PD in a Chinese population and determine whether the genetic variants of genes involved in dopamine metabolism influence the relationship between smoking and risk for PD. Chinese PD patients were recruited from Xuanwu Hospital. Controls were sampled from community. Detailed information on life-long smoking behavior was collected by face-to-face interview. Genotypes were determined for SLC6A3 VNTR, COMT Val108/158Met and MAO-B intron13 A/G polymorphisms by PCR-RFLP, DHPLC and sequencing. Chi-square and logistic regression model were used in the analysis. 176 PD cases and 354 controls were enrolled in this study. 23.9% cases are smokers, compared to 48.0% in controls. Ever smoking is inversely associated with PD (odds ratio=0.14, 95% CI 0.08-0.26, adjusted for age and gender). None of the above-mentioned genetic polymorphisms was associated with PD risk or smoking. When each variant was included in the logistic regression model, the inverse association between smoking and PD remained the same, and the interactions between smoking and variants were not significant in the model. Our data support a reduction of PD risk associated with smoking in a Chinese population. These variants of genes associated with DA uptake and metabolism do not affect the inverse association between smoking and PD. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Bunge, H.; Hagelberg, C.; Travis, B.
2002-12-01
EarthScope will deliver data on structure and dynamics of continental North America and the underlying mantle on an unprecedented scale. Indeed, the scope of EarthScope makes its mission comparable to the large remote sensing efforts that are transforming the oceanographic and atmospheric sciences today. Arguably the main impact of new solid Earth observing systems is to transform our use of geodynamic models increasingly from conditions that are data poor to an environment that is data rich. Oceanographers and meteorologists already have made substantial progress in adapting to this environment, by developing new approaches of interpreting oceanographic and atmospheric data objectively through data assimilation methods in their models. However, a similarly rigorous theoretical framework for merging EarthScope derived solid Earth data with geodynamic models has yet to be devised. Here we explore the feasibility of data assimilation in mantle convection studies in an attempt to fit global geodynamic model calculations explicitly to tomographic and tectonic constraints. This is an inverse problem not quite unlike the inverse problem of finding optimal seismic velocity structures faced by seismologists. We derive the generalized inverse of mantle convection from a variational approach and present the adjoint equations of mantle flow. The substantial computational burden associated with solutions to the generalized inverse problem of mantle convection is made feasible using a highly efficient finite element approach based on the 3-D spherical fully parallelized mantle dynamics code TERRA, implemented on a cost-effective topical PC-cluster (geowulf) dedicated specifically to large-scale geophysical simulations. This dedicated geophysical modeling computer allows us to investigate global inverse convection problems having a spatial discretization of less than 50 km throughout the mantle. We present a synthetic high-resolution modeling experiment to demonstrate that mid-Cretaceous mantle structure can be inferred accurately from our inverse approach assuming present-day mantle structure is well-known, even if an initial first guess assumption about the mid-Cretaceous mantle involved only a simple 1-D radial temperature profile. We suggest that geodynamic inverse modeling should make it possible to infer a number of flow parameters from observational constraints of the mantle.
Palermo, Romina; O’Connor, Kirsty B.; Davis, Joshua M.; Irons, Jessica; McKone, Elinor
2013-01-01
Although good tests are available for diagnosing clinical impairments in face expression processing, there is a lack of strong tests for assessing “individual differences” – that is, differences in ability between individuals within the typical, nonclinical, range. Here, we develop two new tests, one for expression perception (an odd-man-out matching task in which participants select which one of three faces displays a different expression) and one additionally requiring explicit identification of the emotion (a labelling task in which participants select one of six verbal labels). We demonstrate validity (careful check of individual items, large inversion effects, independence from nonverbal IQ, convergent validity with a previous labelling task), reliability (Cronbach’s alphas of.77 and.76 respectively), and wide individual differences across the typical population. We then demonstrate the usefulness of the tests by addressing theoretical questions regarding the structure of face processing, specifically the extent to which the following processes are common or distinct: (a) perceptual matching and explicit labelling of expression (modest correlation between matching and labelling supported partial independence); (b) judgement of expressions from faces and voices (results argued labelling tasks tap into a multi-modal system, while matching tasks tap distinct perceptual processes); and (c) expression and identity processing (results argued for a common first step of perceptual processing for expression and identity). PMID:23840821
Palermo, Romina; O'Connor, Kirsty B; Davis, Joshua M; Irons, Jessica; McKone, Elinor
2013-01-01
Although good tests are available for diagnosing clinical impairments in face expression processing, there is a lack of strong tests for assessing "individual differences"--that is, differences in ability between individuals within the typical, nonclinical, range. Here, we develop two new tests, one for expression perception (an odd-man-out matching task in which participants select which one of three faces displays a different expression) and one additionally requiring explicit identification of the emotion (a labelling task in which participants select one of six verbal labels). We demonstrate validity (careful check of individual items, large inversion effects, independence from nonverbal IQ, convergent validity with a previous labelling task), reliability (Cronbach's alphas of.77 and.76 respectively), and wide individual differences across the typical population. We then demonstrate the usefulness of the tests by addressing theoretical questions regarding the structure of face processing, specifically the extent to which the following processes are common or distinct: (a) perceptual matching and explicit labelling of expression (modest correlation between matching and labelling supported partial independence); (b) judgement of expressions from faces and voices (results argued labelling tasks tap into a multi-modal system, while matching tasks tap distinct perceptual processes); and (c) expression and identity processing (results argued for a common first step of perceptual processing for expression and identity).
NASA Astrophysics Data System (ADS)
Podgornova, O.; Leaney, S.; Liang, L.
2018-07-01
Extracting medium properties from seismic data faces some limitations due to the finite frequency content of the data and restricted spatial positions of the sources and receivers. Some distributions of the medium properties make low impact on the data (including none). If these properties are used as the inversion parameters, then the inverse problem becomes overparametrized, leading to ambiguous results. We present an analysis of multiparameter resolution for the linearized inverse problem in the framework of elastic full-waveform inversion. We show that the spatial and multiparameter sensitivities are intertwined and non-sensitive properties are spatial distributions of some non-trivial combinations of the conventional elastic parameters. The analysis accounts for the Hessian information and frequency content of the data; it is semi-analytical (in some scenarios analytical), easy to interpret and enhances results of the widely used radiation pattern analysis. Single-type scattering is shown to have limited sensitivity, even for full-aperture data. Finite-frequency data lose multiparameter sensitivity at smooth and fine spatial scales. Also, we establish ways to quantify a spatial-multiparameter coupling and demonstrate that the theoretical predictions agree well with the numerical results.
Staton-Tindall, Michele; Duvall, Jamieson; Stevens-Watkins, Danelle; Oser, Carrie B.
2013-01-01
This study examines the role of spirituality as a moderator of the relationship between traumatic life experiences, mental health, and drug use in a sample of African American women. It was hypothesized that there would be an inverse relationship overall between spirituality and mental health and drug use among this sample of African American women. Secondly, was expected that spirituality would moderate the relationship between traumatic life events and mental health and drug use. African American women (n=206) were recruited from the community and from probation officers in three urban areas of a southern state, and face-to-face interviews were completed. Findings indicated that there was a main effect for spirituality (as measured by existential well-being on the Spiritual Well-Being Scale) and traumatic life events, mental health, and alcohol use. In addition, spirituality was a significant moderator of the relationship between traumatic life events and cocaine use. Discussion and implications for African American women are included. PMID:24041186
Evidence for perceptual deficits in associative visual (prosop)agnosia: a single-case study.
Delvenne, Jean François; Seron, Xavier; Coyette, Françoise; Rossion, Bruno
2004-01-01
Associative visual agnosia is classically defined as normal visual perception stripped of its meaning [Archiv für Psychiatrie und Nervenkrankheiten 21 (1890) 22/English translation: Cognitive Neuropsychol. 5 (1988) 155]: these patients cannot access to their stored visual memories to categorize the objects nonetheless perceived correctly. However, according to an influential theory of visual agnosia [Farah, Visual Agnosia: Disorders of Object Recognition and What They Tell Us about Normal Vision, MIT Press, Cambridge, MA, 1990], visual associative agnosics necessarily present perceptual deficits that are the cause of their impairment at object recognition Here we report a detailed investigation of a patient with bilateral occipito-temporal lesions strongly impaired at object and face recognition. NS presents normal drawing copy, and normal performance at object and face matching tasks as used in classical neuropsychological tests. However, when tested with several computer tasks using carefully controlled visual stimuli and taking both his accuracy rate and response times into account, NS was found to have abnormal performances at high-level visual processing of objects and faces. Albeit presenting a different pattern of deficits than previously described in integrative agnosic patients such as HJA and LH, his deficits were characterized by an inability to integrate individual parts into a whole percept, as suggested by his failure at processing structurally impossible three-dimensional (3D) objects, an absence of face inversion effects and an advantage at detecting and matching single parts. Taken together, these observations question the idea of separate visual representations for object/face perception and object/face knowledge derived from investigations of visual associative (prosop)agnosia, and they raise some methodological issues in the analysis of single-case studies of (prosop)agnosic patients.
Davies-Thompson, Jodie; Johnston, Samantha; Tashakkor, Yashar; Pancaroglu, Raika; Barton, Jason J S
2016-08-01
Visual words and faces activate similar networks but with complementary hemispheric asymmetries, faces being lateralized to the right and words to the left. A recent theory proposes that this reflects developmental competition between visual word and face processing. We investigated whether this results in an inverse correlation between the degree of lateralization of visual word and face activation in the fusiform gyri. 26 literate right-handed healthy adults underwent functional MRI with face and word localizers. We derived lateralization indices for cluster size and peak responses for word and face activity in left and right fusiform gyri, and correlated these across subjects. A secondary analysis examined all face- and word-selective voxels in the inferior occipitotemporal cortex. No negative correlations were found. There were positive correlations for the peak MR response between word and face activity within the left hemisphere, and between word activity in the left visual word form area and face activity in the right fusiform face area. The face lateralization index was positively rather than negatively correlated with the word index. In summary, we do not find a complementary relationship between visual word and face lateralization across subjects. The significance of the positive correlations is unclear: some may reflect the influences of general factors such as attention, but others may point to other factors that influence lateralization of function. Copyright © 2016 Elsevier B.V. All rights reserved.
Weak encoding of faces predicts socially influenced judgments of facial attractiveness.
Schnuerch, Robert; Koppehele-Gossel, Judith; Gibbons, Henning
2015-01-01
Conforming to the majority can be seen as a heuristic type of judgment, as it allows the individual to easily choose the most accurate or most socially acceptable type of behavior. People who process the currently to-be-judged items in a superficial, heuristic way should tend to conform to group judgment more than people processing these items in a systematic and elaborate way. We investigated this hypothesis using electroencephalography (EEG), analyzing whether the strength of neural encoding of faces was related to the tendency to adopt a group's evaluative judgments regarding these faces. As expected, we found that the amplitude of the N170, a specific neural correlate of face encoding, was inversely related to conformity across participants: The weaker the faces were encoded, the more the majority response regarding the faces' attractiveness was adopted instead of relying on the actual qualities of the faces. Applying neurophysiological methodology, we thus provide support for previous claims, based on behavioral data and theorizing, that social conformity is a heuristic type of judgment. We propose that weak encoding of judgment-relevant information is a typical, possibly even necessary, precursor of socially adjusted judgments, irrespective of one's current motivational goal (i.e., to be accurate or accepted).
ERIC Educational Resources Information Center
Cornes, Katherine; Donnelly, Nick; Godwin, Hayward; Wenger, Michael J.
2011-01-01
The Thatcher illusion (Thompson, 1980) is considered to be a prototypical illustration of the notion that face perception is dependent on configural processes and representations. We explored this idea by examining the relative contributions of perceptual and decisional processes to the ability of observers to identify the orientation of two…
USDA-ARS?s Scientific Manuscript database
Cotton (Gossypium hirsutum L.) producers in Alabama and across the Cotton Belt are faced with a rapidly expanding problem that decreases yields and increases production costs: herbicide-resistant weeds. Producers are increasingly relying on production methods that raise production costs, such as add...
Slow approach to steady motion of a concave body in a free-molecular gas
NASA Astrophysics Data System (ADS)
Tsuji, Tetsuro; Arai, Junichi; Kawano, Satoyuki
2015-07-01
A body in a free-molecular gas accelerated by a constant external force is considered on the basis of kinetic theory. The body is an infinitely long rectangular hollow column with one face removed, and thus it has a squarish U -shaped cross section. The concave part of the body points toward the direction of motion, and thus the gas molecules may be trapped in the concavity. Gas molecules undergo diffuse reflection on a base part, whereas specular reflection on two lateral parts. It is numerically shown that the velocity of the body approaches a terminal velocity, for which a drag force exerted by the gas counterbalances the external force, in such a way that their difference decreases in proportion to the inverse square of time for a large time. This rate of approach is slower than the known rate proportional to the inverse cube of time in the case of a body without concavity [Aoki et al., Phys. Rev. E 80, 016309 (2009), 10.1103/PhysRevE.80.016309]. Based on the detailed investigation on the velocity distribution function of gas molecules impinging on the body, it is clarified that the concavity prevents some molecules from escaping to infinity. This trapping enhances the effect of recollision between the body and the gas molecules, which is the cause of the inverse power laws, and thus leads to the slower approach.
New insights into old methods for identifying causal rare variants.
Wang, Haitian; Huang, Chien-Hsun; Lo, Shaw-Hwa; Zheng, Tian; Hu, Inchi
2011-11-29
The advance of high-throughput next-generation sequencing technology makes possible the analysis of rare variants. However, the investigation of rare variants in unrelated-individuals data sets faces the challenge of low power, and most methods circumvent the difficulty by using various collapsing procedures based on genes, pathways, or gene clusters. We suggest a new way to identify causal rare variants using the F-statistic and sliced inverse regression. The procedure is tested on the data set provided by the Genetic Analysis Workshop 17 (GAW17). After preliminary data reduction, we ranked markers according to their F-statistic values. Top-ranked markers were then subjected to sliced inverse regression, and those with higher absolute coefficients in the most significant sliced inverse regression direction were selected. The procedure yields good false discovery rates for the GAW17 data and thus is a promising method for future study on rare variants.
Reflection full-waveform inversion using a modified phase misfit function
NASA Astrophysics Data System (ADS)
Cui, Chao; Huang, Jian-Ping; Li, Zhen-Chun; Liao, Wen-Yuan; Guan, Zhe
2017-09-01
Reflection full-waveform inversion (RFWI) updates the low- and highwavenumber components, and yields more accurate initial models compared with conventional full-waveform inversion (FWI). However, there is strong nonlinearity in conventional RFWI because of the lack of low-frequency data and the complexity of the amplitude. The separation of phase and amplitude information makes RFWI more linear. Traditional phase-calculation methods face severe phase wrapping. To solve this problem, we propose a modified phase-calculation method that uses the phase-envelope data to obtain the pseudo phase information. Then, we establish a pseudophase-information-based objective function for RFWI, with the corresponding source and gradient terms. Numerical tests verify that the proposed calculation method using the phase-envelope data guarantees the stability and accuracy of the phase information and the convergence of the objective function. The application on a portion of the Sigsbee2A model and comparison with inversion results of the improved RFWI and conventional FWI methods verify that the pseudophase-based RFWI produces a highly accurate and efficient velocity model. Moreover, the proposed method is robust to noise and high frequency.
Adaptive divergence in the monkey flower Mimulus guttatus is maintained by a chromosomal inversion
Twyford, Alex D.; Friedman, Jannice
2015-01-01
Organisms exhibit an incredible diversity of life history strategies as adaptive responses to environmental variation. The establishment of novel life history strategies involves multilocus polymorphisms, which will be challenging to establish in the face of gene flow and recombination. Theory predicts that adaptive allelic combinations may be maintained and spread if they occur in genomic regions of reduced recombination, such as chromosomal inversion polymorphisms, yet empirical support for this prediction is lacking. Here, we use genomic data to investigate the evolution of divergent adaptive ecotypes of the yellow monkey flower Mimulus guttatus. We show that a large chromosomal inversion polymorphism is the major region of divergence between geographically widespread annual and perennial ecotypes. In contrast, ∼40,000 single nucleotide polymorphisms in collinear regions of the genome show no signal of life history, revealing genomic patterns of diversity have been shaped by localized homogenizing gene flow and large‐scale Pleistocene range expansion. Our results provide evidence for an inversion capturing and protecting loci involved in local adaptation, while also explaining how adaptive divergence can occur with gene flow. PMID:25879251
Lohse, Konrad; Clarke, Magnus; Ritchie, Michael G.; Etges, William J.
2015-01-01
Models of speciation‐with‐gene‐flow have shown that the reduction in recombination between alternative chromosome arrangements can facilitate the fixation of locally adaptive genes in the face of gene flow and contribute to speciation. However, it has proven frustratingly difficult to show empirically that inversions have reduced gene flow and arose during or shortly after the onset of species divergence rather than represent ancestral polymorphisms. Here, we present an analysis of whole genome data from a pair of cactophilic fruit flies, Drosophila mojavensis and D. arizonae, which are reproductively isolated in the wild and differ by several large inversions on three chromosomes. We found an increase in divergence at rearranged compared to colinear chromosomes. Using the density of divergent sites in short sequence blocks we fit a series of explicit models of species divergence in which gene flow is restricted to an initial period after divergence and may differ between colinear and rearranged parts of the genome. These analyses show that D. mojavensis and D. arizonae have experienced postdivergence gene flow that ceased around 270 KY ago and was significantly reduced in chromosomes with fixed inversions. Moreover, we show that these inversions most likely originated around the time of species divergence which is compatible with theoretical models that posit a role of inversions in speciation with gene flow. PMID:25824653
NASA Astrophysics Data System (ADS)
Mouhib, T.; Mouhsen, A.; Oualim, E. M.; Harmouchi, M.; Vigneron, J. P.; Defrance, P.
2009-02-01
Glass substrates coated with a stainless steel-tin double layer were prepared in order to achieve the inverse greenhouse effect. The measurements of the optical properties of the samples indicate that the needed specific spectral selectivity is available. Practical tests of radiative cooling were performed during clear night using a blackbody radiator covered by the coated plate with glass facing the sky. The blackbody temperature was observed to be 6.0 °C below that of the ambient, and the cooling power was estimated to be 27.9 W/m 2. Diurnal measurements indicated that cooling of the blackbody radiator is achieved except for approximately 6 hours around noon.
Order-disorder effects on the elastic properties of CuMPt6 (M=Cr and Co) compounds
NASA Astrophysics Data System (ADS)
Huang, Shuo; Li, Rui-Zi; Qi, San-Tao; Chen, Bao; Shen, Jiang
2014-04-01
The elastic properties of CuMPt6 (M=Cr and Co) in disordered face-centered cubic (fcc) structure and ordered Cu3Au-type structure are studied with lattice inversion embedded-atom method. The calculated lattice constant and Debye temperature agree quite well with the comparable experimental data. The obtained formation enthalpy demonstrates that the Cu3Au-type structure is energetically more favorable. Numerical estimates of the elastic constants, bulk/shear modulus, Young's modulus, Poisson's ratio, elastic anisotropy, and Debye temperature for both compounds are performed, and the results suggest that the disordered fcc structure is much softer than the ordered Cu3Au-type structure.
Razavi, Sonia M; Gonzalez, Marcial; Cuitiño, Alberto M
2015-04-30
We propose a general framework for determining optimal relationships for tensile strength of doubly convex tablets under diametrical compression. This approach is based on the observation that tensile strength is directly proportional to the breaking force and inversely proportional to a non-linear function of geometric parameters and materials properties. This generalization reduces to the analytical expression commonly used for flat faced tablets, i.e., Hertz solution, and to the empirical relationship currently used in the pharmaceutical industry for convex-faced tablets, i.e., Pitt's equation. Under proper parametrization, optimal tensile strength relationship can be determined from experimental results by minimizing a figure of merit of choice. This optimization is performed under the first-order approximation that a flat faced tablet and a doubly curved tablet have the same tensile strength if they have the same relative density and are made of the same powder, under equivalent manufacturing conditions. Furthermore, we provide a set of recommendations and best practices for assessing the performance of optimal tensile strength relationships in general. Based on these guidelines, we identify two new models, namely the general and mechanistic models, which are effective and predictive alternatives to the tensile strength relationship currently used in the pharmaceutical industry. Copyright © 2015 Elsevier B.V. All rights reserved.
Olfactory-visual integration facilitates perception of subthreshold negative emotion.
Novak, Lucas R; Gitelman, Darren R; Schuyler, Brianna; Li, Wen
2015-10-01
A fast growing literature of multisensory emotion integration notwithstanding, the chemical senses, intimately associated with emotion, have been largely overlooked. Moreover, an ecologically highly relevant principle of "inverse effectiveness", rendering maximal integration efficacy with impoverished sensory input, remains to be assessed in emotion integration. Presenting minute, subthreshold negative (vs. neutral) cues in faces and odors, we demonstrated olfactory-visual emotion integration in improved emotion detection (especially among individuals with weaker perception of unimodal negative cues) and response enhancement in the amygdala. Moreover, while perceptual gain for visual negative emotion involved the posterior superior temporal sulcus/pSTS, perceptual gain for olfactory negative emotion engaged both the associative olfactory (orbitofrontal) cortex and amygdala. Dynamic causal modeling (DCM) analysis of fMRI timeseries further revealed connectivity strengthening among these areas during crossmodal emotion integration. That multisensory (but not low-level unisensory) areas exhibited both enhanced response and region-to-region coupling favors a top-down (vs. bottom-up) account for olfactory-visual emotion integration. Current findings thus confirm the involvement of multisensory convergence areas, while highlighting unique characteristics of olfaction-related integration. Furthermore, successful crossmodal binding of subthreshold aversive cues not only supports the principle of "inverse effectiveness" in emotion integration but also accentuates the automatic, unconscious quality of crossmodal emotion synthesis. Copyright © 2015 Elsevier Ltd. All rights reserved.
Inverse target- and cue-priming effects of masked stimuli.
Mattler, Uwe
2007-02-01
The processing of a visual target that follows a briefly presented prime stimulus can be facilitated if prime and target stimuli are similar. In contrast to these positive priming effects, inverse priming effects (or negative compatibility effects) have been found when a mask follows prime stimuli before the target stimulus is presented: Responses are facilitated after dissimilar primes. Previous studies on inverse priming effects examined target-priming effects, which arise when the prime and the target stimuli share features that are critical for the response decision. In contrast, 3 experiments of the present study demonstrate inverse priming effects in a nonmotor cue-priming paradigm. Inverse cue-priming effects exhibited time courses comparable to inverse target-priming effects. Results suggest that inverse priming effects do not arise from specific processes of the response system but follow from operations that are more general.
Electrophysiological evidence for parts and wholes in visual face memory.
Towler, John; Eimer, Martin
2016-10-01
It is often assumed that upright faces are represented in a holistic fashion, while representations of inverted faces are essentially part-based. To assess this hypothesis, we recorded event-related potentials (ERPs) during a sequential face identity matching task where successively presented pairs of upright or inverted faces were either identical or differed with respect to their internal features, their external features, or both. Participants' task was to report on each trial whether the face pair was identical or different. To track the activation of visual face memory representations, we measured N250r components that emerge over posterior face-selective regions during the activation of visual face memory representations by a successful identity match. N250r components to full identity repetitions were smaller and emerged later for inverted as compared to upright faces, demonstrating that image inversion impairs face identity matching processes. For upright faces, N250r components were also elicited by partial repetitions of external or internal features, which suggest that the underlying identity matching processes are not exclusively based on non-decomposable holistic representations. However, the N250r to full identity repetitions was super-additive (i.e., larger than the sum of the two N250r components to partial repetitions of external or internal features) for upright faces, demonstrating that holistic representations were involved in identity matching processes. For inverted faces, N250r components to full and partial identity repetitions were strictly additive, indicating that the identity matching of external and internal features operated in an entirely part-based fashion. These results provide new electrophysiological evidence for qualitative differences between representations of upright and inverted faces in the occipital-temporal face processing system. Copyright © 2016 Elsevier Ltd. All rights reserved.
Induced Pacemaker Activity on Toad Skin
Bueno, Enrique J.; Corchs, Lelio
1968-01-01
The electrical transients produced on the isolated abdominal skin obtained from Bufo arenarum Hensel, under the influence of inward current pulses of constant intensity have been studied. When both faces of the skin are bathed with Ringer's solution, short pulses of inward current give rise to transient variations of the potential difference between both faces of the skin with "all-or-nothing" characteristics (action potentials, AP). When the outer face is bathed with a modified Ringer solution with low sodium content (2.4 mM), the transients are longer and they are only evident when the pulse is several hundred milliseconds long. With even longer pulses (several seconds) a repetitive activity can be elicited, with the electrical characteristics of a "pacemaker" activity. In all these "excitability" phenomena Na+ may be replaced by Li+ in the outer solution. The logarithm of the duration of AP's is inversely related to the logarithm of the increase in concentration of Na+ or Li+ in the solution bathing the external face of the skin. The duration of AP's is increased when the Ca++ concentration in the outer solution is raised. This effect is more evident with low sodium concentration on the outside. The evolution of the slope conductance during repetitive activity has been determined. The site and mechanisms of the "excitable" behavior of the skin and the induced repetitive activity are discussed. Under the experimental conditions employed the behavior of the skin is compared with that of normally excitable plasma membranes. PMID:5692095
An In-Depth Analysis of Exemplary Female Superintendents: A Qualitative Inquiry
ERIC Educational Resources Information Center
Kay, Patricia L.
2012-01-01
The number of women who serve as public school district superintendents is inversely proportionate to the number of women who work in public schools. Men continue to dominate the occupancy of this position. Barriers that women encounter in their career journey and obstacles faced by women who serve in the role of superintendent have been…
Micro-seismic imaging using a source function independent full waveform inversion method
NASA Astrophysics Data System (ADS)
Wang, Hanchen; Alkhalifah, Tariq
2018-03-01
At the heart of micro-seismic event measurements is the task to estimate the location of the source micro-seismic events, as well as their ignition times. The accuracy of locating the sources is highly dependent on the velocity model. On the other hand, the conventional micro-seismic source locating methods require, in many cases manual picking of traveltime arrivals, which do not only lead to manual effort and human interaction, but also prone to errors. Using full waveform inversion (FWI) to locate and image micro-seismic events allows for an automatic process (free of picking) that utilizes the full wavefield. However, full waveform inversion of micro-seismic events faces incredible nonlinearity due to the unknown source locations (space) and functions (time). We developed a source function independent full waveform inversion of micro-seismic events to invert for the source image, source function and the velocity model. It is based on convolving reference traces with these observed and modeled to mitigate the effect of an unknown source ignition time. The adjoint-state method is used to derive the gradient for the source image, source function and velocity updates. The extended image for the source wavelet in Z axis is extracted to check the accuracy of the inverted source image and velocity model. Also, angle gathers is calculated to assess the quality of the long wavelength component of the velocity model. By inverting for the source image, source wavelet and the velocity model simultaneously, the proposed method produces good estimates of the source location, ignition time and the background velocity for synthetic examples used here, like those corresponding to the Marmousi model and the SEG/EAGE overthrust model.
Rapid inverse planning for pressure-driven drug infusions in the brain.
Rosenbluth, Kathryn H; Martin, Alastair J; Mittermeyer, Stephan; Eschermann, Jan; Dickinson, Peter J; Bankiewicz, Krystof S
2013-01-01
Infusing drugs directly into the brain is advantageous to oral or intravenous delivery for large molecules or drugs requiring high local concentrations with low off-target exposure. However, surgeons manually planning the cannula position for drug delivery in the brain face a challenging three-dimensional visualization task. This study presents an intuitive inverse-planning technique to identify the optimal placement that maximizes coverage of the target structure while minimizing the potential for leakage outside the target. The technique was retrospectively validated using intraoperative magnetic resonance imaging of infusions into the striatum of non-human primates and into a tumor in a canine model and applied prospectively to upcoming human clinical trials.
Binary zone-plate array for a parallel joint transform correlator applied to face recognition.
Kodate, K; Hashimoto, A; Thapliya, R
1999-05-10
Taking advantage of small aberrations, high efficiency, and compactness, we developed a new, to our knowledge, design procedure for a binary zone-plate array (BZPA) and applied it to a parallel joint transform correlator for the recognition of the human face. Pairs of reference and unknown images of faces are displayed on a liquid-crystal spatial light modulator (SLM), Fourier transformed by the BZPA, intensity recorded on an optically addressable SLM, and inversely Fourier transformed to obtain correlation signals. Consideration of the bandwidth allows the relations among the channel number, the numerical aperture of the zone plates, and the pattern size to be determined. Experimentally a five-channel parallel correlator was implemented and tested successfully with a 100-person database. The design and the fabrication of a 20-channel BZPA for phonetic character recognition are also included.
Workflows for Full Waveform Inversions
NASA Astrophysics Data System (ADS)
Boehm, Christian; Krischer, Lion; Afanasiev, Michael; van Driel, Martin; May, Dave A.; Rietmann, Max; Fichtner, Andreas
2017-04-01
Despite many theoretical advances and the increasing availability of high-performance computing clusters, full seismic waveform inversions still face considerable challenges regarding data and workflow management. While the community has access to solvers which can harness modern heterogeneous computing architectures, the computational bottleneck has fallen to these often manpower-bounded issues that need to be overcome to facilitate further progress. Modern inversions involve huge amounts of data and require a tight integration between numerical PDE solvers, data acquisition and processing systems, nonlinear optimization libraries, and job orchestration frameworks. To this end we created a set of libraries and applications revolving around Salvus (http://salvus.io), a novel software package designed to solve large-scale full waveform inverse problems. This presentation focuses on solving passive source seismic full waveform inversions from local to global scales with Salvus. We discuss (i) design choices for the aforementioned components required for full waveform modeling and inversion, (ii) their implementation in the Salvus framework, and (iii) how it is all tied together by a usable workflow system. We combine state-of-the-art algorithms ranging from high-order finite-element solutions of the wave equation to quasi-Newton optimization algorithms using trust-region methods that can handle inexact derivatives. All is steered by an automated interactive graph-based workflow framework capable of orchestrating all necessary pieces. This naturally facilitates the creation of new Earth models and hopefully sparks new scientific insights. Additionally, and even more importantly, it enhances reproducibility and reliability of the final results.
Caharel, Stéphanie; Leleu, Arnaud; Bernard, Christian; Viggiano, Maria-Pia; Lalonde, Robert; Rebaï, Mohamed
2013-11-01
The properties of the face-sensitive N170 component of the event-related brain potential (ERP) were explored through an orientation discrimination task using natural faces, objects, and Arcimboldo paintings presented upright or inverted. Because Arcimboldo paintings are composed of non-face objects but have a global face configuration, they provide great control to disentangle high-level face-like or object-like visual processes at the level of the N170, and may help to examine the implication of each hemisphere in the global/holistic processing of face formats. For upright position, N170 amplitudes in the right occipito-temporal region did not differ between natural faces and Arcimboldo paintings but were larger for both of these categories than for objects, supporting the view that as early as the N170 time-window, the right hemisphere is involved in holistic perceptual processing of face-like configurations irrespective of their features. Conversely, in the left hemisphere, N170 amplitudes differed between Arcimboldo portraits and natural faces, suggesting that this hemisphere processes local facial features. For upside-down orientation in both hemispheres, N170 amplitudes did not differ between Arcimboldo paintings and objects, but were reduced for both categories compared to natural faces, indicating that the disruption of holistic processing with inversion leads to an object-like processing of Arcimboldo paintings due to the lack of local facial features. Overall, these results provide evidence that global/holistic perceptual processing of faces and face-like formats involves the right hemisphere as early as the N170 time-window, and that the local processing of face features is rather implemented in the left hemisphere. © 2013.
Luo, Wei-Ping; Fang, Yu-Jing; Lu, Min-Shan; Zhong, Xiao; Chen, Yu-Ming; Zhang, Cai-Xia
2015-04-14
The colour of the edible portion of vegetables and fruit reflects the presence of specific micronutrients and phytochemicals. No existing studies have examined the relationship between the intake of vegetable and fruit colour groups and the risk of colorectal cancer. The present study, therefore, aimed to investigate these associations in a Chinese population. A case-control study was conducted between July 2010 and July 2014 in Guangzhou, China, in which 1057 consecutively recruited cases of colorectal cancer were frequency-matched to 1057 controls by age (5-year interval), sex and residence (rural/urban). A validated FFQ was used to collect dietary information during face-to-face interviews. Vegetables and fruit were classified into four groups according to the colour of their primarily edible parts: green; orange/yellow; red/purple; white. Unconditional logistic regression models were used to estimate the OR and 95 % CI. A higher consumption of orange/yellow, red/purple and white vegetables and fruit was inversely associated with the risk of colorectal cancer, with adjusted OR of 0·16 (95 % CI 0·12, 0·22) for orange/yellow, 0·23 (95 % CI 0·17, 0·31) for red/purple and 0·53 (95 % CI 0·40, 0·70) for white vegetables and fruit when the highest and lowest quartiles were compared. Total vegetable intake and total fruit intake have also been found to be inversely associated with colorectal cancer risk. However, the intake of green vegetable and fruit was not associated with colorectal cancer risk. The results of the present study, therefore, suggest that a greater intake of orange/yellow, red/purple and white vegetables and fruit is inversely associated with the risk of colorectal cancer.
Staton-Tindall, Michele; Duvall, Jamieson; Stevens-Watkins, Danelle; Oser, Carrie B
2013-09-01
This study examines the role of spirituality as a moderator of the relationship between traumatic life experiences, mental health, and drug use in a sample of African American women. It was hypothesized that there would be an inverse relationship overall between spirituality and mental health and drug use among this sample of African American women. Secondly, was expected that spirituality would moderate the relationship between traumatic life events and mental health and drug use. African American women (n = 206) were recruited from the community and from probation officers in three urban areas of a southern state, and face-to-face interviews were completed. Findings indicated that there was a main effect for spirituality (as measured by existential well-being on the Spiritual Well-Being Scale) and traumatic life events, mental health, and alcohol use. In addition, spirituality was a significant moderator of the relationship between traumatic life events and cocaine use. Discussion and implications for African American women are included.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Small, Ward; Pearson, Mark A.; Metz, Tom R.
Dow Corning SE 1700 (reinforced polydimethylsiloxane) porous structures were made by direct ink writing (DIW) in a face centered tetragonal (FCT) configuration. The filament diameter was 250 μm. Structures consisting of 4, 8, or 12 layers were fabricated with center-to-center filament spacing (“road width” (RW)) of 475, 500, 525, 550, or 575 μm. Three compressive load-unload cycles to 2000 kPa were performed on four separate areas of each sample; three samples of each thickness and filament spacing were tested. At a given strain during the third loading phase, stress varied inversely with porosity. At 10% strain, the stress was nearlymore » independent of the number of layers (i.e., thickness). At higher strains (20- 40%), the stress was highest for the 4-layer structure; the 8- and 12-layer structures were nearly equivalent suggesting that the load deflection is independent of number of layers above 8 layers. Intra-and inter-sample variability of the load deflection response was higher for thinner and less porous structures.« less
Ultrafast magnetic vortex core switching driven by the topological inverse Faraday effect.
Taguchi, Katsuhisa; Ohe, Jun-ichiro; Tatara, Gen
2012-09-21
We present a theoretical discovery of an unconventional mechanism of inverse Faraday effect which acts selectively on topological magnetic structures. The effect, topological inverse Faraday effect, is induced by the spin Berry's phase of the magnetic structure when a circularly polarized light is applied. Thus a spin-orbit interaction is not necessary unlike that in the conventional inverse Faraday effect. We demonstrate by numerical simulation that topological inverse Faraday effect realizes ultrafast switching of a magnetic vortex within a switching time of 150 ps without magnetic field.
The Monetary Valuation of Lifetime Health Improvement and Life Expectancy Gains in Turkey
Tekeşin, Cem
2017-01-01
The main objective of this study is to estimate the monetary value of the gains of healthy days and life expectancy due to the ambient air quality standard that came into effect in 2014 by estimating the country-specific value of a life year (VOLY) and the value of the healthier and longer life (VHLL) for Turkey. Contingent valuation method is adopted to reveal individuals’ willingness to pay for an improvement of health condition and the extension of their life expectancy by avoiding respiratory and lung related illnesses. VHLL is composed of two parts, WTP for an extension of one’s life years (VOLY) and for an increase in the number of healthy days throughout one’s life time (VHLL-VOLY). We found that close to 80% of WTP is allocated to the latter component of VHLL and only 20% is for VOLY mainly due to Islamic beliefs of the respondents. A total of 1314 observations are collected by face-to-face interviews from Afsin-Elbistan, Kutahya-Tavsanli and Ankara. The estimated VHLL and VOLY are [41,750 TL, 10,258 TL] with all the observations, [30,185 TL, 7132 TL] for Afsin-Elbistan, [31,718 TL, 7081 TL] for Kutahya-Tavsanli and [52,334 TL, 14,813 TL] for Ankara. The Inverse-U shaped relationship between Age and WTP is confirmed. The income elasticities of WTP is found to be close to 0.5 for all study areas while an Inverse-U shaped relationship between the household income and Income Elasticity of WTP is observed in the income group based analysis. Age and household income are the two prominent determinants of VHLL. PMID:28961227
The Monetary Valuation of Lifetime Health Improvement and Life Expectancy Gains in Turkey.
Ara, Shihomi; Tekeşin, Cem
2017-09-29
The main objective of this study is to estimate the monetary value of the gains of healthy days and life expectancy due to the ambient air quality standard that came into effect in 2014 by estimating the country-specific value of a life year (VOLY) and the value of the healthier and longer life (VHLL) for Turkey. Contingent valuation method is adopted to reveal individuals' willingness to pay for an improvement of health condition and the extension of their life expectancy by avoiding respiratory and lung related illnesses. VHLL is composed of two parts, WTP for an extension of one's life years (VOLY) and for an increase in the number of healthy days throughout one's life time (VHLL-VOLY). We found that close to 80% of WTP is allocated to the latter component of VHLL and only 20% is for VOLY mainly due to Islamic beliefs of the respondents. A total of 1314 observations are collected by face-to-face interviews from Afsin-Elbistan, Kutahya-Tavsanli and Ankara. The estimated VHLL and VOLY are [41,750 TL, 10,258 TL] with all the observations, [30,185 TL, 7132 TL] for Afsin-Elbistan, [31,718 TL, 7081 TL] for Kutahya-Tavsanli and [52,334 TL, 14,813 TL] for Ankara. The Inverse-U shaped relationship between Age and WTP is confirmed. The income elasticities of WTP is found to be close to 0.5 for all study areas while an Inverse-U shaped relationship between the household income and Income Elasticity of WTP is observed in the income group based analysis. Age and household income are the two prominent determinants of VHLL.
Luo, Hong; Fang, Yu-Jing; Lu, Min-Shan; Pan, Zhi-Zhong; Huang, Jing; Chen, Yu-Ming; Zhang, Cai-Xia
2018-05-24
The effect of vitamin A (VA) and vitamin E (VE) on colorectal cancer (CRC) risk is controversial. The aim of this study is to examine the association between serum concentrations and dietary intakes of VA and VE and the risk of CRC in Guangdong, China. A total of 535 cases and 552 sex and age-matched (5-year interval) controls were recruited during July 2010 to September 2014. Dietary information was assessed by face-to-face interviews using a validated food frequency questionnaire. Concentrations of VA and VE were measured by high-performance liquid chromatography. Multivariable logistic regression was used to estimate the odds ratios (ORs) and 95% confidence interval (CI) after adjusting for various potential confounders. A higher intake of VA and VE was found to be associated with 52 and 43% reduction in CRC risk. The ORs of the highest quartile compared with the lowest quartile intake were 0.48 (95% CI: 0.31, 0.73, Ptrend<0.01) for VA and 0.57 (95% CI: 0.37, 0.88, Ptrend<0.01) for VE. An inverse association was also found between serum retinol and CRC risk, with an adjusted OR (95% CI) of 0.28 (0.19-0.43) (Ptrend<0.01). However, no statistically significant association was found between serum α-tocopherol and CRC risk. Stratified analysis by sex showed that serum retinol and dietary VA and VE were inversely associated with CRC risk in both sexes. This study supported the hypothesis that lower serum levels of retinol and lower intakes of VA and VE were associated with the risk of CRC in a Chinese population.
NASA Astrophysics Data System (ADS)
Abanov, Ar.; Chubukov, Andrey V.; Schmalian, J.
2003-03-01
We present the full analysis of the normal state properties of the spin-fermion model near the antiferromagnetic instability in two dimensions. The model describes low-energy fermions interacting with their own collective spin fluctuations, which soften at the antiferromagnetic transition. We argue that in 2D, the system has two typical energies-an effective spin-fermion interaction bar g and an energy ysf below which the system behaves as a Fermi liquid. The ratio of the two determines the dimensionless coupling constant for spin-fermion interaction lambda (2) alpha /line g /omega _{sf} . We show that u scales with the spin correlation length and diverges at criticality. This divergence implies that the conventional perturbative expansion breaks down. We develop a novel approach to the problem-the expansion in either the inverse number of hot spots in the Brillouin zone, or the inverse number of fermionic flavours-which allows us to explicitly account for all terms which diverge as powers of u, and treat the remaining, O(logu) terms in the RG formalism. We apply this technique to study the properties of the spin-fermion model in various frequency and temperature regimes. We present the results for the fermionic spectral function, spin susceptibility, optical conductivity and other observables. We compare our results in detail with the normal state data for the cuprates, and argue that the spin-fermion model is capable of explaining the anomalous normal state properties of the high Tc materials. We also show that the conventional Ӓ theory of the quantum-critical behaviour is inapplicable in 2D due to the singularity of the Ӓ vertex.
A Student's Dilemma: Is There a Trade-Off between a Higher Salary or Higher GPA
ERIC Educational Resources Information Center
Diette, Timothy M.; Raghav, Manu
2016-01-01
In this paper, we explore whether there is a relationship between average grades earned in a course and the national average salaries of graduates of the major associated with the course. Using student-level data from a selective private liberal arts college, we find an inverse relationship. The result suggests that students face a trade-off…
Characterization of a Method for Inverse Heat Conduction Using Real and Simulated Thermocouple Data
NASA Technical Reports Server (NTRS)
Pizzo, Michelle E.; Glass, David E.
2017-01-01
It is often impractical to instrument the external surface of high-speed vehicles due to the aerothermodynamic heating. Temperatures can instead be measured internal to the structure using embedded thermocouples, and direct and inverse methods can then be used to estimate temperature and heat flux on the external surface. Two thermocouples embedded at different depths are required to solve direct and inverse problems, and filtering schemes are used to reduce noise in the measured data. Accuracy in the estimated surface temperature and heat flux is dependent on several factors. Factors include the thermocouple location through the thickness of a material, the sensitivity of the surface solution to the error in the specified location of the embedded thermocouples, and the sensitivity to the error in thermocouple data. The effect of these factors on solution accuracy is studied using the methodology discussed in the work of Pizzo, et. al.1 A numerical study is performed to determine if there is an optimal depth at which to embed one thermocouple through the thickness of a material assuming that a second thermocouple is installed on the back face. Solution accuracy will be discussed for a range of embedded thermocouple depths. Moreover, the sensitivity of the surface solution to (a) the error in the specified location of the embedded thermocouple and to (b) the error in the thermocouple data are quantified using numerical simulation, and the results are discussed.
Adaptive divergence in the monkey flower Mimulus guttatus is maintained by a chromosomal inversion.
Twyford, Alex D; Friedman, Jannice
2015-06-01
Organisms exhibit an incredible diversity of life history strategies as adaptive responses to environmental variation. The establishment of novel life history strategies involves multilocus polymorphisms, which will be challenging to establish in the face of gene flow and recombination. Theory predicts that adaptive allelic combinations may be maintained and spread if they occur in genomic regions of reduced recombination, such as chromosomal inversion polymorphisms, yet empirical support for this prediction is lacking. Here, we use genomic data to investigate the evolution of divergent adaptive ecotypes of the yellow monkey flower Mimulus guttatus. We show that a large chromosomal inversion polymorphism is the major region of divergence between geographically widespread annual and perennial ecotypes. In contrast, ∼40,000 single nucleotide polymorphisms in collinear regions of the genome show no signal of life history, revealing genomic patterns of diversity have been shaped by localized homogenizing gene flow and large-scale Pleistocene range expansion. Our results provide evidence for an inversion capturing and protecting loci involved in local adaptation, while also explaining how adaptive divergence can occur with gene flow. © 2015 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.
2-D traveltime and waveform inversion for improved seismic imaging: Naga Thrust and Fold Belt, India
NASA Astrophysics Data System (ADS)
Jaiswal, Priyank; Zelt, Colin A.; Bally, Albert W.; Dasgupta, Rahul
2008-05-01
Exploration along the Naga Thrust and Fold Belt in the Assam province of Northeast India encounters geological as well as logistic challenges. Drilling for hydrocarbons, traditionally guided by surface manifestations of the Naga thrust fault, faces additional challenges in the northeast where the thrust fault gradually deepens leaving subtle surface expressions. In such an area, multichannel 2-D seismic data were collected along a line perpendicular to the trend of the thrust belt. The data have a moderate signal-to-noise ratio and suffer from ground roll and other acquisition-related noise. In addition to data quality, the complex geology of the thrust belt limits the ability of conventional seismic processing to yield a reliable velocity model which in turn leads to poor subsurface image. In this paper, we demonstrate the application of traveltime and waveform inversion as supplements to conventional seismic imaging and interpretation processes. Both traveltime and waveform inversion utilize the first arrivals that are typically discarded during conventional seismic processing. As a first step, a smooth velocity model with long wavelength characteristics of the subsurface is estimated through inversion of the first-arrival traveltimes. This velocity model is then used to obtain a Kirchhoff pre-stack depth-migrated image which in turn is used for the interpretation of the fault. Waveform inversion is applied to the central part of the seismic line to a depth of ~1 km where the quality of the migrated image is poor. Waveform inversion is performed in the frequency domain over a series of iterations, proceeding from low to high frequency (11-19 Hz) using the velocity model from traveltime inversion as the starting model. In the end, the pre-stack depth-migrated image and the waveform inversion model are jointly interpreted. This study demonstrates that a combination of traveltime and waveform inversion with Kirchhoff pre-stack depth migration is a promising approach for the interpretation of geological structures in a thrust belt.
Choline and betaine intake and colorectal cancer risk in Chinese population: a case-control study.
Lu, Min-Shan; Fang, Yu-Jing; Pan, Zhi-Zhong; Zhong, Xiao; Zheng, Mei-Chun; Chen, Yu-Ming; Zhang, Cai-Xia
2015-01-01
Few studies have examined the association of choline and betaine intake with colorectal cancer risk, although they might play an important role in colorectal cancer development because of their role as methyl donors. The aim of this study was to examine the relationship between consumption of choline and betaine and colorectal cancer risk in a Chinese population. A case-control study was conducted between July 2010 and December 2013 in Guangzhou, China. Eight hundred and ninety consecutively recruited colorectal cancer cases were frequency matched to 890 controls by age (5-year interval) and sex. Dietary information was assessed with a validated food frequency questionnaire by face-to-face interviews. The logistic regression model was used to estimate multivariate odds ratios (ORs) and 95% confidence intervals (CIs). Total choline intake was inversely associated with colorectal cancer risk after adjustment for various lifestyle and dietary factors. The multivariate-adjusted OR was 0.54 (95%CI = 0.37-0.80, Ptrend <0.01) comparing the highest with the lowest quartile. No significant associations were observed for betaine or total choline+betaine intakes. For choline-containing compounds, lower colorectal cancer risk was associated with higher intakes of choline from phosphatidylcholine, glycerophosphocholine and sphingomyelin but not for free choline and phosphocholine. The inverse association of total choline intake with colorectal cancer risk was observed in both men and women, colon and rectal cancer. These inverse associations were not modified by folate intake. These results indicate that high intake of total choline is associated with a lower risk of colorectal cancer.
Choline and Betaine Intake and Colorectal Cancer Risk in Chinese Population: A Case-Control Study
Pan, Zhi-Zhong; Zhong, Xiao; Zheng, Mei-Chun; Chen, Yu-Ming; Zhang, Cai-Xia
2015-01-01
Background Few studies have examined the association of choline and betaine intake with colorectal cancer risk, although they might play an important role in colorectal cancer development because of their role as methyl donors. The aim of this study was to examine the relationship between consumption of choline and betaine and colorectal cancer risk in a Chinese population. Methodology/Principal Findings A case-control study was conducted between July 2010 and December 2013 in Guangzhou, China. Eight hundred and ninety consecutively recruited colorectal cancer cases were frequency matched to 890 controls by age (5-year interval) and sex. Dietary information was assessed with a validated food frequency questionnaire by face-to-face interviews. The logistic regression model was used to estimate multivariate odds ratios (ORs) and 95% confidence intervals (CIs). Total choline intake was inversely associated with colorectal cancer risk after adjustment for various lifestyle and dietary factors. The multivariate-adjusted OR was 0.54 (95%CI = 0.37-0.80, Ptrend <0.01) comparing the highest with the lowest quartile. No significant associations were observed for betaine or total choline+betaine intakes. For choline-containing compounds, lower colorectal cancer risk was associated with higher intakes of choline from phosphatidylcholine, glycerophosphocholine and sphingomyelin but not for free choline and phosphocholine. The inverse association of total choline intake with colorectal cancer risk was observed in both men and women, colon and rectal cancer. These inverse associations were not modified by folate intake. Conclusions These results indicate that high intake of total choline is associated with a lower risk of colorectal cancer. PMID:25785727
NASA Astrophysics Data System (ADS)
Rajaji, V.; Pal, Koushik; Sarma, Saurav Ch.; Joseph, B.; Peter, Sebastian C.; Waghmare, Umesh V.; Narayana, Chandrabhas
2018-04-01
We report high-pressure Raman scattering measurements on the tetragonal phase of InTe corroborated with the first-principles density functional theory and synchrotron x-ray diffraction measurements. Anomalous pressure-dependent linewidths of the A1 g and Eg phonon modes provide evidence of an isostructural electronic transition at ˜3.6 GPa . The first-principles theoretical analysis reveals that it is associated with a semiconductor-to-metal transition due to increased density of states near the Fermi level. Further, this pressure induced metallization acts as a precursor for structural phase transition to a face centered cubic phase (F m 3 ¯m ) at ˜6.0 GPa . Interestingly, theoretical results reveal a pressure induced band inversion at the Z and M points of the Brillouin zone corresponding to pressures ˜1.0 and ˜1.4 GPa , respectively. As the parity of bands undergoing inversions is the same, the topology of the electronic state remains unchanged, and hence InTe retains its trivial band topology (Z2=0 ) . The pressure dependent behavior of the A1 g and Eg modes can be understood based on the results from the synchrotron x-ray diffraction, which shows anisotropic compressibility of the lattice in the a and c directions. Our Raman measurements up to ˜19 GPa further confirms the pressure induced structural phase transition from a face-centered to primitive cubic (F m 3 ¯m to P m 3 ¯m ) at P ˜15 GPa .
NASA Astrophysics Data System (ADS)
Castelo, A.; Mendioroz, A.; Celorrio, R.; Salazar, A.; López de Uralde, P.; Gorosmendi, I.; Gorostegui-Colinas, E.
2017-05-01
Lock-in vibrothermography is used to characterize vertical kissing and open cracks in metals. In this technique the crack heats up during ultrasound excitation due mainly to friction between the defect's faces. We have solved the inverse problem, consisting in determining the heat source distribution produced at cracks under amplitude modulated ultrasound excitation, which is an ill-posed inverse problem. As a consequence the minimization of the residual is unstable. We have stabilized the algorithm introducing a penalty term based on Total Variation functional. In the inversion, we combine amplitude and phase surface temperature data obtained at several modulation frequencies. Inversions of synthetic data with added noise indicate that compact heat sources are characterized accurately and that the particular upper contours can be retrieved for shallow heat sources. The overall shape of open and homogeneous semicircular strip-shaped heat sources representing open half-penny cracks can also be retrieved but the reconstruction of the deeper end of the heat source loses contrast. Angle-, radius- and depth-dependent inhomogeneous heat flux distributions within these semicircular strips can also be qualitatively characterized. Reconstructions of experimental data taken on samples containing calibrated heat sources confirm the predictions from reconstructions of synthetic data. We also present inversions of experimental data obtained from a real welded Inconel 718 specimen. The results are in good qualitative agreement with the results of liquids penetrants testing.
Feder, Jeffrey L.; Nosil, Patrik; Flaxman, Samuel M.
2014-01-01
Many hypotheses have been put forth to explain the origin and spread of inversions, and their significance for speciation. Several recent genic models have proposed that inversions promote speciation with gene flow due to the adaptive significance of the genes contained within them and because of the effects inversions have on suppressing recombination. However, the consequences of inversions for the dynamics of genome wide divergence across the speciation continuum remain unclear, an issue we examine here. We review a framework for the genomics of speciation involving the congealing of the genome into alternate adaptive states representing species (“genome wide congealing”). We then place inversions in this context as examples of how genetic hitchhiking can potentially hasten genome wide congealing. Specifically, we use simulation models to (i) examine the conditions under which inversions may speed genome congealing and (ii) quantify predicted magnitudes of these effects. Effects of inversions on promoting speciation were most common and pronounced when inversions were initially fixed between populations before secondary contact and adaptation involved many genes with small fitness effects. Further work is required on the role of underdominance and epistasis between a few loci of major effect within inversions. The results highlight five important aspects of the roles of inversions in speciation: (i) the geographic context of the origins and spread of inversions, (ii) the conditions under which inversions can facilitate divergence, (iii) the magnitude of that facilitation, (iv) the extent to which the buildup of divergence is likely to be biased within vs. outside of inversions, and (v) the dynamics of the appearance and disappearance of exceptional divergence within inversions. We conclude by discussing the empirical challenges in showing that inversions play a central role in facilitating speciation with gene flow. PMID:25206365
Measuring the face-sensitive N170 with a gaming EEG system: A validation study.
de Lissa, Peter; Sörensen, Sidsel; Badcock, Nicholas; Thie, Johnson; McArthur, Genevieve
2015-09-30
The N170 is a "face-sensitive" event-related potential (ERP) that occurs at around 170ms over occipito-temporal brain regions. The N170's potential to provide insight into the neural processing of faces in certain populations (e.g., children and adults with cognitive impairments) is limited by its measurement in scientific laboratories that can appear threatening to some people. The advent of cheap, easy-to-use portable gaming EEG systems provides an opportunity to record EEG in new contexts and populations. This study tested the validity of the face-sensitive N170 ERP measured with an adapted commercial EEG system (the Emotiv EPOC) that is used at home by gamers. The N170 recorded through both the gaming EEG system and the research EEG system exhibited face-sensitivity, with larger mean amplitudes in response to the face stimuli than the non-face stimuli, and a delayed N170 peak in response to face inversion. The EPOC system produced very similar N170 ERPs to a research-grade Neuroscan system, and was capable of recording face-sensitivity in the N170, validating its use as research tool in this arena. This opens new possibilities for measuring the face-sensitive N170 ERP in people who cannot travel to a traditional ERP laboratory (e.g., elderly people in care), who cannot tolerate laboratory conditions (e.g., people with autism), or who need to be tested in situ for practical or experimental reasons (e.g., children in schools). Copyright © 2015 Elsevier B.V. All rights reserved.
Poirier, Frédéric J A M; Faubert, Jocelyn
2012-06-22
Facial expressions are important for human communications. Face perception studies often measure the impact of major degradation (e.g., noise, inversion, short presentations, masking, alterations) on natural expression recognition performance. Here, we introduce a novel face perception technique using rich and undegraded stimuli. Participants modified faces to create optimal representations of given expressions. Using sliders, participants adjusted 53 face components (including 37 dynamic) including head, eye, eyebrows, mouth, and nose shape and position. Data was collected from six participants and 10 conditions (six emotions + pain + gender + neutral). Some expressions had unique features (e.g., frown for anger, upward-curved mouth for happiness), whereas others had shared features (e.g., open eyes and mouth for surprise and fear). Happiness was different from other emotions. Surprise was different from other emotions except fear. Weighted sum morphing provides acceptable stimuli for gender-neutral and dynamic stimuli. Many features were correlated, including (1) head size with internal feature sizes as related to gender, (2) internal feature scaling, and (3) eyebrow height and eye openness as related to surprise and fear. These findings demonstrate the method's validity for measuring the optimal facial expressions, which we argue is a more direct measure of their internal representations.
Decadal-scale coastal cliff retreat in southern and central California
NASA Astrophysics Data System (ADS)
Young, Adam P.
2018-01-01
Airborne LiDAR data collected in 1998 and 2009-2010 were used to measure coastal cliff erosion and retreat between the Mexico/California border and Bodega Head, California. Cliff erosion was detected along 44% of the 595 km of shoreline evaluated, while the remaining cliffs were relatively stable. The mean cliff top retreat rate was 0.12 m/yr, while mean retreat averaged over the entire cliff face was 0.04 m/yr. The maximum cliff top and face retreat rates were 4.2 and 3.8 m/yr, respectively. Historical ( 1930s to 1998) and recent retreat rates were significantly inversely correlated for areas with large historical or recent cliff retreat, such that locations with elevated historical retreat had low levels of recent retreat and locations with elevated recent retreat were preceded by low rates of historical retreat. The strength of this inverse correlation increased with cliff change magnitudes up to r2 of 0.91 for cliff top retreat rates > 2.9 m/yr. Mean recent retreat rates were 52-83% lower than mean historical retreat rates. Although beaches can protect cliffs against wave-driven erosion, cliffs fronted by beaches retreated 49% more than cliffs without beaches. On average, unarmored cliff faces retreated 0.05 m/yr between 1998 and 2009-2010, about three times faster than artificially armored cliffs. Alongshore metrics of wave-cliff impact, precipitation, and cliff hardness were generally not well correlated with recent cliff changes. A cliff hazard metric is used to detect cliff steepening and areas prone to future cliff top failures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Andersen, David R.; Bershady, Matthew A., E-mail: david.andersen@nrc-cnrc.gc.ca, E-mail: mab@astro.wisc.edu
2013-05-01
Using the integral field unit DensePak on the WIYN 3.5 m telescope we have obtained H{alpha} velocity fields of 39 nearly face-on disks at echelle resolutions. High-quality, uniform kinematic data and a new modeling technique enabled us to derive accurate and precise kinematic inclinations with mean i{sub kin} = 23 Degree-Sign for 90% of these galaxies. Modeling the kinematic data as single, inclined disks in circular rotation improves upon the traditional tilted-ring method. We measure kinematic inclinations with a precision in sin i of 25% at 20 Degree-Sign and 6% at 30 Degree-Sign . Kinematic inclinations are consistent with photometricmore » and inverse Tully-Fisher inclinations when the sample is culled of galaxies with kinematic asymmetries, for which we give two specific prescriptions. Kinematic inclinations can therefore be used in statistical ''face-on'' Tully-Fisher studies. A weighted combination of multiple, independent inclination measurements yield the most precise and accurate inclination. Combining inverse Tully-Fisher inclinations with kinematic inclinations yields joint probability inclinations with a precision in sin i of 10% at 15 Degree-Sign and 5% at 30 Degree-Sign . This level of precision makes accurate mass decompositions of galaxies possible even at low inclination. We find scaling relations between rotation speed and disk-scale length identical to results from more inclined samples. We also observe the trend of more steeply rising rotation curves with increased rotation speed and light concentration. This trend appears to be uncorrelated with disk surface brightness.« less
Quantifying facial expression recognition across viewing conditions.
Goren, Deborah; Wilson, Hugh R
2006-04-01
Facial expressions are key to social interactions and to assessment of potential danger in various situations. Therefore, our brains must be able to recognize facial expressions when they are transformed in biologically plausible ways. We used synthetic happy, sad, angry and fearful faces to determine the amount of geometric change required to recognize these emotions during brief presentations. Five-alternative forced choice conditions involving central viewing, peripheral viewing and inversion were used to study recognition among the four emotions. Two-alternative forced choice was used to study affect discrimination when spatial frequency information in the stimulus was modified. The results show an emotion and task-dependent pattern of detection. Facial expressions presented with low peak frequencies are much harder to discriminate from neutral than faces defined by either mid or high peak frequencies. Peripheral presentation of faces also makes recognition much more difficult, except for happy faces. Differences between fearful detection and recognition tasks are probably due to common confusions with sadness when recognizing fear from among other emotions. These findings further support the idea that these emotions are processed separately from each other.
Estimating Human Trabecular Meshwork Stiffness by Numerical Modeling and Advanced OCT Imaging.
Wang, Ke; Johnstone, Murray A; Xin, Chen; Song, Shaozhen; Padilla, Steven; Vranka, Janice A; Acott, Ted S; Zhou, Kai; Schwaner, Stephen A; Wang, Ruikang K; Sulchek, Todd; Ethier, C Ross
2017-09-01
The purpose of this study was to estimate human trabecular meshwork (hTM) stiffness, thought to be elevated in glaucoma, using a novel indirect approach, and to compare results with direct en face atomic force microscopy (AFM) measurements. Postmortem human eyes were perfused to measure outflow facility and identify high- and low-flow regions (HF, LF) by tracer. Optical coherence tomography (OCT) images were obtained as Schlemm's canal luminal pressure was directly manipulated. TM stiffness was deduced by an inverse finite element modeling (FEM) approach. A series of AFM forcemaps was acquired along a line traversing the anterior angle on a radially cut flat-mount corneoscleral wedge with TM facing upward. The elastic modulus of normal hTM estimated by inverse FEM was 70 ± 20 kPa (mean ± SD), whereas glaucomatous hTM was slightly stiffer (98 ± 19 kPa). This trend was consistent with TM stiffnesses measured by AFM: normal hTM stiffness = 1.37 ± 0.56 kPa, which was lower than glaucomatous hTM stiffness (2.75 ± 1.19 kPa). None of these differences were statistically significant. TM in HF wedges was softer than that in LF wedges for both normal and glaucomatous eyes based on the inverse FEM approach but not by AFM. Outflow facility was significantly correlated with TM stiffness estimated by FEM in six human eyes (P = 0.018). TM stiffness is higher, but only modestly so, in glaucomatous patients. Outflow facility in both normal and glaucomatous human eyes appears to associate with TM stiffness. This evidence motivates further studies to investigate factors underlying TM biomechanical property regulation.
NASA Astrophysics Data System (ADS)
Delay, Frederick; Badri, Hamid; Fahs, Marwan; Ackerer, Philippe
2017-12-01
Dual porosity models become increasingly used for simulating groundwater flow at the large scale in fractured porous media. In this context, model inversions with the aim of retrieving the system heterogeneity are frequently faced with huge parameterizations for which descent methods of inversion with the assistance of adjoint state calculations are well suited. We compare the performance of discrete and continuous forms of adjoint states associated with the flow equations in a dual porosity system. The discrete form inherits from previous works by some of the authors, as the continuous form is completely new and here fully differentiated for handling all types of model parameters. Adjoint states assist descent methods by calculating the gradient components of the objective function, these being a key to good convergence of inverse solutions. Our comparison on the basis of synthetic exercises show that both discrete and continuous adjoint states can provide very similar solutions close to reference. For highly heterogeneous systems, the calculation grid of the continuous form cannot be too coarse, otherwise the method may show lack of convergence. This notwithstanding, the continuous adjoint state is the most versatile form as its non-intrusive character allows for plugging an inversion toolbox quasi-independent from the code employed for solving the forward problem.
Study of Inverse Ni-based Photonic Crystal using the Microradian X-ray Diffraction
NASA Astrophysics Data System (ADS)
Vasilieva, A. V.; Grigoryeva, N. A.; Mistonov, A. A.; Sapoletova, N. A.; Napolskii, K. S.; Eliseev, A. A.; Lukashin, A. V.; Tretyakov, Yu D.; Petukhov, A. V.; Byelov, D.; Chernyshov, D.; Okorokov, A. I.; Bouwman, W. G.; Grigoriev, S. V.
2010-10-01
Inverse photonic nickel-based crystal films formed by electrocrystallization of metal inside the voids of polymer artificial opal have been studied using the microradian X-ray diffraction. Analysis of the diffraction images agrees with an face-centred cubic (FCC) structure with the lattice constant a0 = 650 ± 10 nm and indicates two types of stacking sequences coexisting in the crystal (twins of ABCABC... and ACBACB... ordering motifs), the ratio between them being 4:5 The transverse structural correlation length Ltran is 2.4 ± 0.1 μm, which corresponds to a sample thickness of 6 layers. The in-plane structural correlation length Llong is 3.4 ± 0.2 μm, and the structure mosaic is of order of 10°.
Soy and isoflavone intake are associated with reduced risk of ovarian cancer in southeast china.
Zhang, Min; Xie, Xing; Lee, Andy H; Binns, Colin W
2004-01-01
To investigate whether intake of soy and isoflavones has an inverse association with ovarian cancer risk, a case-control study was conducted in Hangzhou, China. Cases were 254 patients with histologically confirmed epithelial ovarian cancer. The 652 controls comprised 340 hospital visitors, 261 non-neoplastic hospital outpatients, and 51 women recruited from the community. Habitual dietary intakes including 9 soy foods were measured by face-to-face interview using a validated and reliable food-frequency questionnaire. Unconditional logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) accounting for age, demographic characteristics, hormonal factors, and total energy intake. Intake of soy and isoflavones was inversely related to the risk of ovarian cancer. Compared with the highest versus the lowest quartile intake, the ORs were 0.50 (95% CI = 0.31-0.82) for total soy foods and 0.51 (95% CI = 0.31-0.85) for isoflavones. Among subgroups of soy foods and isoflavones, the ORs for soybeans, bean curd, daidzein, genistein, and glycitein were 0.35 (95% CI = 0.22-0.58), 0.49 (95% CI = 0.29-0.81), 0.52 (95% CI = 0.31-0.87), 0.50 (95% CI = 0.30-0.84), and 0.59 (95% CI = 0.35-0.97), respectively.
The fusiform face area: a cortical region specialized for the perception of faces
Kanwisher, Nancy; Yovel, Galit
2006-01-01
Faces are among the most important visual stimuli we perceive, informing us not only about a person's identity, but also about their mood, sex, age and direction of gaze. The ability to extract this information within a fraction of a second of viewing a face is important for normal social interactions and has probably played a critical role in the survival of our primate ancestors. Considerable evidence from behavioural, neuropsychological and neurophysiological investigations supports the hypothesis that humans have specialized cognitive and neural mechanisms dedicated to the perception of faces (the face-specificity hypothesis). Here, we review the literature on a region of the human brain that appears to play a key role in face perception, known as the fusiform face area (FFA). Section 1 outlines the theoretical background for much of this work. The face-specificity hypothesis falls squarely on one side of a longstanding debate in the fields of cognitive science and cognitive neuroscience concerning the extent to which the mind/brain is composed of: (i) special-purpose (‘domain-specific’) mechanisms, each dedicated to processing a specific kind of information (e.g. faces, according to the face-specificity hypothesis), versus (ii) general-purpose (‘domain-general’) mechanisms, each capable of operating on any kind of information. Face perception has long served both as one of the prime candidates of a domain-specific process and as a key target for attack by proponents of domain-general theories of brain and mind. Section 2 briefly reviews the prior literature on face perception from behaviour and neurophysiology. This work supports the face-specificity hypothesis and argues against its domain-general alternatives (the individuation hypothesis, the expertise hypothesis and others). Section 3 outlines the more recent evidence on this debate from brain imaging, focusing particularly on the FFA. We review the evidence that the FFA is selectively engaged in face perception, by addressing (and rebutting) five of the most widely discussed alternatives to this hypothesis. In §4, we consider recent findings that are beginning to provide clues into the computations conducted in the FFA and the nature of the representations the FFA extracts from faces. We argue that the FFA is engaged both in detecting faces and in extracting the necessary perceptual information to recognize them, and that the properties of the FFA mirror previously identified behavioural signatures of face-specific processing (e.g. the face-inversion effect). Section 5 asks how the computations and representations in the FFA differ from those occurring in other nearby regions of cortex that respond strongly to faces and objects. The evidence indicates clear functional dissociations between these regions, demonstrating that the FFA shows not only functional specificity but also area specificity. We end by speculating in §6 on some of the broader questions raised by current research on the FFA, including the developmental origins of this region and the question of whether faces are unique versus whether similarly specialized mechanisms also exist for other domains of high-level perception and cognition. PMID:17118927
Unbalanced-flow, fluid-mixing plug with metering capabilities
NASA Technical Reports Server (NTRS)
England, John Dwight (Inventor); Kelley, Anthony R. (Inventor); Van Buskirk, Paul D. (Inventor)
2009-01-01
A fluid mixer plug has holes formed therethrough such that a remaining portion is closed to fluid flow. The plug's inlet face defines a central circuit region and a ring-shaped region with the ring-shaped region including at least some of the plug's remaining portion so-closed to fluid flow. This remaining portion or closed region at each radius R of the ring shaped region satisfies a radius independent, flow-based relationship. Entry openings are defined in the plug's inlet face in correspondence with the holes. The entry openings define an open flow area at each radius of the ring-shaped region. The open flow area at each such radius satisfies the inverse of the flow-based relationship defining the closed regions of the plug.
1,3-Bis(chloro-meth-yl)-2-methyl-5-nitro-benzene.
Shao, Chang-Lun; Li, Chunyuan; Liu, Zhen; Wei, Mei-Yan; Wang, Chang-Yun
2008-03-20
The title compound, C(9)H(9)Cl(2)NO(2), is a natural product isolated from the endophytic fungus No. B77 of the mangrove tree from the South China Sea coast. In the crystal structure, the mol-ecules lie on twofold axes and form offset stacks through face-to-face π-π inter-actions. Adjacent mol-ecules in each stack are related by a centre of inversion and have an inter-planar separation of 3.53 (1) Å, with a centroid-centroid distance of 3.76 (1) Å. Between stacks, there are C-H⋯O inter-actions to the nitro groups and Cl⋯Cl contacts of 3.462 (1) Å.
Henríquez-Hernández, Luis Alberto; Boada, Luis D; Pérez-Arellano, José Luis; Carranza, Cristina; Ruiz-Suárez, Norberto; Jaén Sánchez, Nieves; Valerón, Pilar F; Zumbado, Manuel; Camacho, María; Luzardo, Octavio P
2016-10-01
Polychlorinated biphenyls (PCBs) are toxic and persistent chemicals produced between 1930s and 1980s, which accumulate in humans and wildlife. Although a decreasing trend of PCB levels in humans has been described in developed countries, mainly as a consequence of strict regulations and remediation plans, an inverse trend has been recently reported in people from developing countries. We had the opportunity of sampling a series of African immigrants recently arrived to the Spanish archipelago of the Canary Islands, in which high levels of PCBs have been described, and we studied the relationships between their level of contamination and health status. A total of 570 subjects who underwent a complete medical examination and a face-to-face interview were recruited for this study. Hematological and biochemical parameters (blood and urine) were determined in all participants. Serology for the diagnostic of infectious diseases was also performed, and direct identification of parasites was performed in feces, urine or blood samples when appropriate. It is remarkable that up to 26.0% of the population had intestinal parasites, and we found an inverse relationship between PCB levels and parasitism and parasitic diseases: median values of PCBs were lower in parasitized subjects than in subjects without parasites in stool (237.6ng/g fat vs. 154.4ng/g fat for marker PCBs, p=0.015) and median values of dioxin-like PCBs were lower in subjects carrying pathogen parasites than among subjects showing non-pathogen parasites in stool (0.0 ng/g fat vs. 13.1ng/g fat, respectively; p=0.001). Although this inverse association had been described in some vertebrates this is the first study reporting such an association in humans. Furthermore, it has been also recently described that PCBs may disrupt iron metabolism, and we found a direct relationship between serum iron and total PCBs burden (r=0.231, p=0.025), suggesting that PCBs, although at subclinical level, could play a role on iron homeostasis. Although the role of PCBs in parasitism and in the iron metabolism needs future research, our findings may help to understand the adverse health outcomes associated to environmental exposure to PCBs and they might be used in exposed populations as indicators of subtle effects due to environmental insult. Copyright © 2015 Elsevier Inc. All rights reserved.
Atreja, Ashish; Mehta, Neil; Miller, Deborah; Moore, Shirley; Nichols, Karen; Miller, Holly; Harris, C Martin
2005-01-01
Disabled and elderly populations are the fastest growing segment of Internet usage. However, these people face an “Inverse Information law”- access to appropriate information is particularly difficult to those who need it the most. Our tertiary care Multiple Sclerosis (MS) center received funding to develop a MS specific patient portal linked to web messaging system so as to empower patients to become more active participants in their health care. In order to design an effective portal, we conducted a qualitative study using focus groups and direct observation techniques. The study explores the perceptions, expectations and interactions of MS patients with the portal and underscores the many challenges MS patients face in getting quality health information on the Internet. Many of the patient barriers were due to inappropriate font sizes, low contrast, cluttering of web page and use of dynamic and flashing objects. Some of these issues are not addressed by Section 508 accessibility guidelines. We believe that any future patient portal or health information web site needs to address these issues and educate the patients about accessibility options to enhance utilization and user satisfaction. PMID:16778993
Jin, Zi-yi; Han, Ren-qiang; Zhang, Xiao-feng; Wang, Xu-shan; Wu, Ming; Zhang, Zuo-feng; Zhao, Jin-kou
2013-02-01
To understand the relationship between green tea drinking and/or garlic consumption and lung cancer. A population-based case-control study was conducted in Ganyu county, Jiangsu province. Epidemiological data including demography, lifestyle, environmental exposures and dietary habits were collected by face-to-face interviews using a standardized questionnaire. Unconditional logistic regression was used to estimate adjusted odds ratios (OR) and their 95% confidence intervals (CI) in both univariate and multivariate analyses. Both green tea drinking and garlic consumption were inversely associated with lung cancer and the adjusted ORs were: 0.78 (95%CI: 0.65 - 0.95) for green tea, 0.79 (95%CI: 0.66 - 0.95) for garlic intake, and 0.69 (95%CI: 0.53 - 0.89) for both, respectively. They also modified the associations of smoking, fried food intake and cooking oil under high-temperature with lung cancer as risk factors. Potential interactions were found between garlic or green tea and the risk factors of lung cancer. Both green tea drinking and garlic consumption might serve as protective factors on lung cancer.
NASA Astrophysics Data System (ADS)
Pedesseau, Laurent; Jouanna, Paul
2004-12-01
The SASP (semianalytical stochastic perturbations) method is an original mixed macro-nano-approach dedicated to the mass equilibrium of multispecies phases, periphases, and interphases. This general method, applied here to the reflexive relation Ck⇔μk between the concentrations Ck and the chemical potentials μk of k species within a fluid in equilibrium, leads to the distribution of the particles at the atomic scale. The macroaspects of the method, based on analytical Taylor's developments of chemical potentials, are intimately mixed with the nanoaspects of molecular mechanics computations on stochastically perturbed states. This numerical approach, directly linked to definitions, is universal by comparison with current approaches, DLVO Derjaguin-Landau-Verwey-Overbeek, grand canonical Monte Carlo, etc., without any restriction on the number of species, concentrations, or boundary conditions. The determination of the relation Ck⇔μk implies in fact two problems: a direct problem Ck⇒μk and an inverse problem μk⇒Ck. Validation of the method is demonstrated in case studies A and B which treat, respectively, a direct problem and an inverse problem within a free saturated gypsum solution. The flexibility of the method is illustrated in case study C dealing with an inverse problem within a solution interphase, confined between two (120) gypsum faces, remaining in connection with a reference solution. This last inverse problem leads to the mass equilibrium of ions and water molecules within a 3 Å thick gypsum interface. The major unexpected observation is the repulsion of SO42- ions towards the reference solution and the attraction of Ca2+ ions from the reference solution, the concentration being 50 times higher within the interphase as compared to the free solution. The SASP method is today the unique approach able to tackle the simulation of the number and distribution of ions plus water molecules in such extreme confined conditions. This result is of prime importance for all coupled chemical-mechanical problems dealing with interfaces, and more generally for a wide variety of applications such as phase changes, osmotic equilibrium, surface energy, etc., in complex chemical-physics situations.
Integrated aquitard-aquifer flow with a mixed-type well-face boundary and skin effect
NASA Astrophysics Data System (ADS)
Feng, Qinggao; Zhan, Hongbin
2016-03-01
A general analytical model describing groundwater flow to a partially penetrating well pumped at a constant rate in a leaky confined aquifer is developed. The model incorporates the effects of aquitard storage, aquifer anisotropy, wellbore storage and a finite well skin by treating the aquitard leakage as an aquitard-aquifer interface flow problem, and considers the well-face as a mixed-type or non-uniform flux (NUF) rather than a uniform flux (UF) boundary condition, which is novel. The solution is obtained using the Laplace transform coupled with separation of variables and discretization methods, followed by the numerical inverse Laplace transform. Moreover, the solution unifies some cases for flow to a partially penetrating well in a leaky confined aquifer including Perina and Lee (2006), Feng and Zhan (2015) and Hunt (2005) or confined aquifer including Chiu et al. (2007), Yang et al. (2006) and Hantush (1964). The newly developed NUF solution is compared with the UF solution. The NUF drawdown is larger than the UF drawdown at early time, while the NUF drawdown is smaller than the UF drawdown at intermediate and late times. The non-uniform flux along the well-face has significant impact on drawdown in the skin zone, while the UF solution can completely replace the NUF solution at a radial distance from the pumped well equaling to or greater than the aquifer thickness. The NUF and UF drawdowns for no skin case are remarkably smaller than that for the positive skin case and larger than that for the negative skin case. A thicker well skin results in a smaller drawdown in the skin zone.
Fitness consequences of polymorphic inversions in the zebra finch genome.
Knief, Ulrich; Hemmrich-Stanisak, Georg; Wittig, Michael; Franke, Andre; Griffith, Simon C; Kempenaers, Bart; Forstmeier, Wolfgang
2016-09-29
Inversion polymorphisms constitute an evolutionary puzzle: they should increase embryo mortality in heterokaryotypic individuals but still they are widespread in some taxa. Some insect species have evolved mechanisms to reduce the cost of embryo mortality but humans have not. In birds, a detailed analysis is missing although intraspecific inversion polymorphisms are regarded as common. In Australian zebra finches (Taeniopygia guttata), two polymorphic inversions are known cytogenetically and we set out to detect these two and potentially additional inversions using genomic tools and study their effects on embryo mortality and other fitness-related and morphological traits. Using whole-genome SNP data, we screened 948 wild zebra finches for polymorphic inversions and describe four large (12-63 Mb) intraspecific inversion polymorphisms with allele frequencies close to 50 %. Using additional data from 5229 birds and 9764 eggs from wild and three captive zebra finch populations, we show that only the largest inversions increase embryo mortality in heterokaryotypic males, with surprisingly small effect sizes. We test for a heterozygote advantage on other fitness components but find no evidence for heterosis for any of the inversions. Yet, we find strong additive effects on several morphological traits. The mechanism that has carried the derived inversion haplotypes to such high allele frequencies remains elusive. It appears that selection has effectively minimized the costs associated with inversions in zebra finches. The highly skewed distribution of recombination events towards the chromosome ends in zebra finches and other estrildid species may function to minimize crossovers in the inverted regions.
Learn the Lagrangian: A Vector-Valued RKHS Approach to Identifying Lagrangian Systems.
Cheng, Ching-An; Huang, Han-Pang
2016-12-01
We study the modeling of Lagrangian systems with multiple degrees of freedom. Based on system dynamics, canonical parametric models require ad hoc derivations and sometimes simplification for a computable solution; on the other hand, due to the lack of prior knowledge in the system's structure, modern nonparametric models in machine learning face the curse of dimensionality, especially in learning large systems. In this paper, we bridge this gap by unifying the theories of Lagrangian systems and vector-valued reproducing kernel Hilbert space. We reformulate Lagrangian systems with kernels that embed the governing Euler-Lagrange equation-the Lagrangian kernels-and show that these kernels span a subspace capturing the Lagrangian's projection as inverse dynamics. By such property, our model uses only inputs and outputs as in machine learning and inherits the structured form as in system dynamics, thereby removing the need for the mundane derivations for new systems as well as the generalization problem in learning from scratches. In effect, it learns the system's Lagrangian, a simpler task than directly learning the dynamics. To demonstrate, we applied the proposed kernel to identify the robot inverse dynamics in simulations and experiments. Our results present a competitive novel approach to identifying Lagrangian systems, despite using only inputs and outputs.
Spatial-Numerical Associations Enhance the Short-Term Memorization of Digit Locations
Thevenot, Catherine; Dewi, Jasinta; Lavenex, Pamela B.; Bagnoud, Jeanne
2018-01-01
Little is known about how spatial-numerical associations (SNAs) affect the way individuals process their environment, especially in terms of learning and memory. In this study, we investigated the potential effects of SNAs in a digit memory task in order to determine whether spatially organized mental representations of numbers can influence the short-term encoding of digits positioned on an external display. To this aim, we designed a memory game in which participants had to match pairs of identical digits in a 9 × 2 matrix of cards. The nine cards of the first row had to be turned face up and then face down, one by one, to reveal a digit from 1 to 9. When a card was turned face up in the second row, the position of the matching digit in the first row had to be recalled. Our results showed that performance was better when small numbers were placed on the left side of the row and large numbers on the right side (i.e., congruent) as compared to the inverse (i.e., incongruent) or a random configuration. Our findings suggests that SNAs can enhance the memorization of digit positions and therefore that spatial mental representations of numbers can play an important role on the way humans process and encode the information around them. To our knowledge, this study is the first that reaches this conclusion in a context where digits did not have to be processed as numerical values. PMID:29867631
Neural bases of different cognitive strategies for facial affect processing in schizophrenia.
Fakra, Eric; Salgado-Pineda, Pilar; Delaveau, Pauline; Hariri, Ahmad R; Blin, Olivier
2008-03-01
To examine the neural basis and dynamics of facial affect processing in schizophrenic patients as compared to healthy controls. Fourteen schizophrenic patients and fourteen matched controls performed a facial affect identification task during fMRI acquisition. The emotional task included an intuitive emotional condition (matching emotional faces) and a more cognitively demanding condition (labeling emotional faces). Individual analysis for each emotional condition, and second-level t-tests examining both within-, and between-group differences, were carried out using a random effects approach. Psychophysiological interactions (PPI) were tested for variations in functional connectivity between amygdala and other brain regions as a function of changes in experimental conditions (labeling versus matching). During the labeling condition, both groups engaged similar networks. During the matching condition, schizophrenics failed to activate regions of the limbic system implicated in the automatic processing of emotions. PPI revealed an inverse functional connectivity between prefrontal regions and the left amygdala in healthy volunteers but there was no such change in patients. Furthermore, during the matching condition, and compared to controls, patients showed decreased activation of regions involved in holistic face processing (fusiform gyrus) and increased activation of regions associated with feature analysis (inferior parietal cortex, left middle temporal lobe, right precuneus). Our findings suggest that schizophrenic patients invariably adopt a cognitive approach when identifying facial affect. The distributed neocortical network observed during the intuitive condition indicates that patients may resort to feature-based, rather than configuration-based, processing and may constitute a compensatory strategy for limbic dysfunction.
Chu, Denise A; Bryant, Richard A; Gatt, Justine M; Harris, Anthony W F
2016-07-01
Enhanced threat-related processing is associated with both elevated anxiety and childhood exposure to trauma. Given the paucity of evidence regarding the effects of childhood and adult trauma exposure on subsequent psychophysiological processes in the absence of psychopathology, we investigated the relative impacts of childhood interpersonal and non-interpersonal trauma, as well as adult trauma exposure on neural processing of threat in healthy adults. We measured peak amplitudes of the N170 face-sensitive visual ERP component response to non-conscious and conscious Angry (threat) versus Happy (non-threat, positive) and Neutral (non-threat baseline) faces at temporo-occipital sites (right-T6; left-T5) in 489 psychiatrically asymptomatic adults (aged 18-70 years, 54% women, 94% right-handed). N170 peak amplitude differences between Angry vs Happy or Neutral faces were calculated and subjected to hierarchical multiple regression analysis, with trauma types (childhood interpersonal, childhood non-interpersonal and adult trauma) entered as predictors of interest. After controlling for sociodemographic and health factors, N170 peak amplitudes for non-conscious Angry vs Happy faces were inversely associated with childhood interpersonal trauma at T6 and adult trauma exposure at T5. Post-hoc repeated measures ANOVA indicated that unlike adults without trauma exposure, trauma-exposed adults failed to show significantly reduced N170 responses to Happy relative to Angry faces during non-conscious processing. This suggests that childhood interpersonal and adult trauma exposure are associated with a failure to differentiate between non-threat or positive and threat-related emotion cues. This is consistent with generalised hypervigilance seen in PTSD, and suggests trauma exposure is associated with a generalized heightened responsivity to non-conscious non-threat or positive as well as threat-related emotion cues in psychiatrically healthy adults. Copyright © 2016 Elsevier Ltd. All rights reserved.
The Inversion Effect for Chinese Characters Is Modulated by Radical Organization
ERIC Educational Resources Information Center
Luo, Canhuang; Chen, Wei; Zhang, Ye
2017-01-01
In studies of visual object recognition, strong inversion effects accompany the acquisition of expertise and imply the involvement of configural processing. Chinese literacy results in sensitivity to the orthography of Chinese characters. While there is some evidence that this orthographic sensitivity results in an inversion effect, and thus…
Eckstein, Monika; Markett, Sebastian; Kendrick, Keith M; Ditzen, Beate; Liu, Fang; Hurlemann, Rene; Becker, Benjamin
2017-04-01
The hypothalamic neuropeptide oxytocin (OT) has received increasing attention for its role in modulating social-emotional processes across species. Previous studies on using intranasal-OT in humans point to a crucial engagement of the amygdala in the observed neuromodulatory effects of OT under task and rest conditions. However, the amygdala is not a single homogenous structure, but rather a set of structurally and functionally heterogeneous nuclei that show distinct patterns of connectivity with limbic and frontal emotion-processing regions. To determine potential differential effects of OT on functional connectivity of the amygdala subregions, 79 male participants underwent resting-state fMRI following randomized intranasal-OT or placebo administration. In line with previous studies OT increased the connectivity of the total amygdala with dorso-medial prefrontal regions engaged in emotion regulation. In addition, OT enhanced coupling of the total amygdala with cerebellar regions. Importantly, OT differentially altered the connectivity of amygdala subregions with distinct up-stream cortical nodes, particularly prefrontal/parietal, and cerebellar down-stream regions. OT-induced increased connectivity with cerebellar regions were largely driven by effects on the centromedial and basolateral subregions, whereas increased connectivity with prefrontal regions were largely mediated by right superficial and basolateral subregions. OT decreased connectivity of the centromedial subregions with core hubs of the emotional face processing network in temporal, occipital and parietal regions. Preliminary findings suggest that effects on the superficial amygdala-prefrontal pathway were inversely associated with levels of subclinical depression, possibly indicating that OT modulation may be blunted in the context of increased pathological load. Together, the present findings suggest a subregional-specific modulatory role of OT on amygdala-centered emotion processing networks in humans. Copyright © 2017 Elsevier Inc. All rights reserved.
Loureiro, Cláudia; Pereira, Joana L; Pedrosa, M Arminda; Gonçalves, Fernando; Castro, Bruno B
2013-01-01
Competition is a major driving force in freshwaters, especially given the cyclic nature and dynamics of pelagic food webs. Competition is especially important in the initial species assortment during colonization and re-colonization events, which depends strongly on the environmental context. Subtle changes, such as saline intrusion, may disrupt competitive relationships and, thus, influence community composition. Bearing this in mind, our objective was to assess whether low salinity levels (using NaCl as a proxy) alter the competitive outcome (measured as the rate of population biomass increase) of Daphnia-Simocephalus experimental microcosms, taking into account interactions with priority effects (sequential species arrival order). With this approach, we aimed to experimentally demonstrate a putative mechanism of differential species sorting in brackish environments or in freshwaters facing secondary salinization. Experiments considered three salinity levels, regarding NaCl added (0.00, 0.75 and 1.50 g L(-1)), crossed with three competition scenarios (no priority, priority of Daphnia over Simocephalus, and vice-versa). At lower NaCl concentrations (0.00 and 0.75 g L(-1)), Daphnia was a significantly superior competitor, irrespective of the species inoculation order, suggesting negligible priority effects. However, the strong decrease in Daphnia population growth at 1.50 g L(-1) alleviated the competitive pressure on Simocephalus, causing an inversion of the competitive outcome in favour of Simocephalus. The intensity of this inversion depended on the competition scenario. This salinity-mediated disruption of the competitive outcome demonstrates that subtle environmental changes produce indirect effects in key ecological mechanisms, thus altering community composition, which may lead to serious implications in terms of ecosystem functioning (e.g. lake regime shifts due to reduced grazing) and biodiversity.
Zhang, Min; Huang, Jian; Xie, Xing; Holman, C D'Arcy J
2009-03-15
To investigate effects of dietary mushrooms and joint effects of mushrooms and green tea on breast cancer, a case-control study was conducted in southeast China in 2004-2005. The incident cases were 1,009 female patients aged 20-87 years with histologically confirmed breast cancer. The 1,009 age-matched controls were healthy women randomly recruited from outpatient breast clinics. Information on frequency and quantity of dietary intake of mushrooms and tea consumption, usual diet, and lifestyle were collected by face-to-face interview using a validated and reliable questionnaire. Compared with nonconsumers, the Odds ratios (Ors) were 0.36 (95% CI = 0.25-0.51) and 0.53 (0.38-0.73) for daily intake of >or=10 g fresh mushrooms and >or=4 g dried mushrooms, based on multivariate logistic regression analysis adjusting for established and potential confounders. There were dose-response relationships with significant tests for trend (p < 0.001). The inverse association was found in both pre- and postmenopausal women. Compared with those who consumed neither mushrooms nor green tea, the ORs were 0.11 (0.06-0.20) and 0.18 (0.11-0.29) for daily high intake of fresh and dried mushrooms combined with consuming beverages made from >or=1.05 g dried green tea leaves per day. The corresponding linear trends were statistically significant for joint effect (p < 0.001). We conclude that higher dietary intake of mushrooms decreased breast cancer risk in pre- and postmenopausal Chinese women and an additional decreased risk of breast cancer from joint effect of mushrooms and green tea was observed. More research is warranted to examine the effects of dietary mushrooms and mechanism of joint effects of phytochemicals on breast cancer.
Lavington, Erik; Kern, Andrew D
2017-11-06
Chromosomal inversions are a ubiquitous feature of genetic variation. Theoretical models describe several mechanisms by which inversions can drive adaptation and be maintained as polymorphisms. While inversions have been shown previously to be under selection, or contain genetic variation under selection, the specific phenotypic consequences of inversions leading to their maintenance remain unclear. Here we use genomic sequence and expression data from the Drosophila Genetic Reference Panel (DGRP) to explore the effects of two cosmopolitan inversions, In ( 2L ) t and In ( 3R ) Mo , on patterns of transcriptional variation. We demonstrate that each inversion has a significant effect on transcript abundance for hundreds of genes across the genome. Inversion-affected loci (IAL) appear both within inversions as well as on unlinked chromosomes. Importantly, IAL do not appear to be influenced by the previously reported genome-wide expression correlation structure. We found that five genes involved with sterol uptake, four of which are Niemann-Pick Type 2 orthologs, are upregulated in flies with In ( 3R ) Mo but do not have SNPs in linkage disequilibrium (LD) with the inversion. We speculate that this upregulation is driven by genetic variation in mod ( mdg4 ) that is in LD with In ( 3R ) Mo We find that there is little evidence for a regional or position effect of inversions on gene expression at the chromosomal level, but do find evidence for the distal breakpoint of In ( 3R ) Mo interrupting one gene and possibly disassociating the two flanking genes from regulatory elements. Copyright © 2017 Lavington and Kern.
Lavington, Erik; Kern, Andrew D.
2017-01-01
Chromosomal inversions are a ubiquitous feature of genetic variation. Theoretical models describe several mechanisms by which inversions can drive adaptation and be maintained as polymorphisms. While inversions have been shown previously to be under selection, or contain genetic variation under selection, the specific phenotypic consequences of inversions leading to their maintenance remain unclear. Here we use genomic sequence and expression data from the Drosophila Genetic Reference Panel (DGRP) to explore the effects of two cosmopolitan inversions, In(2L)t and In(3R)Mo, on patterns of transcriptional variation. We demonstrate that each inversion has a significant effect on transcript abundance for hundreds of genes across the genome. Inversion-affected loci (IAL) appear both within inversions as well as on unlinked chromosomes. Importantly, IAL do not appear to be influenced by the previously reported genome-wide expression correlation structure. We found that five genes involved with sterol uptake, four of which are Niemann-Pick Type 2 orthologs, are upregulated in flies with In(3R)Mo but do not have SNPs in linkage disequilibrium (LD) with the inversion. We speculate that this upregulation is driven by genetic variation in mod(mdg4) that is in LD with In(3R)Mo. We find that there is little evidence for a regional or position effect of inversions on gene expression at the chromosomal level, but do find evidence for the distal breakpoint of In(3R)Mo interrupting one gene and possibly disassociating the two flanking genes from regulatory elements. PMID:28916647
Polarity dependence of Mn incorporation in (Ga,Mn)N superlattices
NASA Astrophysics Data System (ADS)
Tropf, L.; Kunert, G.; Jakieła, R.; Wilhelm, R. A.; Figge, S.; Grenzer, J.; Hommel, D.
2016-03-01
In the context of recent efforts to combine high Mn concentrations in (Ga,Mn)N with a pronounced p-type carrier density, (Ga,Mn)N/GaN:Mg-superlattices have been fabricated using plasma-assisted molecular beam epitaxy. Profiles of the dopant atomic densities in the heterostructures are obtained by secondary ion mass spectroscopy. They show an abrupt drop of two to three orders of magnitude in both Mn and Mg concentrations after the first GaN:Mg layer above a critical Mg-flux. Scanning electron microscopy before and after selective etching reveals a polarity inversion from originally Ga-face to N-face GaN in samples in which high Mg fluxes were applied. From our observations, we are able to draw an analogy between the impurity incorporation laws of Mg and Mn.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Senesi, Andrew; Lee, Byeongdu
Herein, a general method to calculate the scattering functions of polyhedra, including both regular and semi-regular polyhedra, is presented. These calculations may be achieved by breaking a polyhedron into sets of congruent pieces, thereby reducing computation time by taking advantage of Fourier transforms and inversion symmetry. Each piece belonging to a set or subunit can be generated by either rotation or translation. Further, general strategies to compute truncated, concave and stellated polyhedra are provided. Using this method, the asymptotic behaviors of the polyhedral scattering functions are compared with that of a sphere. It is shown that, for a regular polyhedron,more » the form factor oscillation at highqis correlated with the face-to-face distance. In addition, polydispersity affects the Porod constant. The ideas presented herein will be important for the characterization of nanomaterials using small-angle scattering.« less
Inverse Doppler Effects in Broadband Acoustic Metamaterials
Zhai, S. L.; Zhao, X. P.; Liu, S.; Shen, F. L.; Li, L. L.; Luo, C. R.
2016-01-01
The Doppler effect refers to the change in frequency of a wave source as a consequence of the relative motion between the source and an observer. Veselago theoretically predicted that materials with negative refractions can induce inverse Doppler effects. With the development of metamaterials, inverse Doppler effects have been extensively investigated. However, the ideal material parameters prescribed by these metamaterial design approaches are complex and also challenging to obtain experimentally. Here, we demonstrated a method of designing and experimentally characterising arbitrary broadband acoustic metamaterials. These omni-directional, double-negative, acoustic metamaterials are constructed with ‘flute-like’ acoustic meta-cluster sets with seven double meta-molecules; these metamaterials also overcome the limitations of broadband negative bulk modulus and mass density to provide a region of negative refraction and inverse Doppler effects. It was also shown that inverse Doppler effects can be detected in a flute, which has been popular for thousands of years in Asia and Europe. PMID:27578317
Inverse Doppler Effects in Broadband Acoustic Metamaterials
NASA Astrophysics Data System (ADS)
Zhai, S. L.; Zhao, X. P.; Liu, S.; Shen, F. L.; Li, L. L.; Luo, C. R.
2016-08-01
The Doppler effect refers to the change in frequency of a wave source as a consequence of the relative motion between the source and an observer. Veselago theoretically predicted that materials with negative refractions can induce inverse Doppler effects. With the development of metamaterials, inverse Doppler effects have been extensively investigated. However, the ideal material parameters prescribed by these metamaterial design approaches are complex and also challenging to obtain experimentally. Here, we demonstrated a method of designing and experimentally characterising arbitrary broadband acoustic metamaterials. These omni-directional, double-negative, acoustic metamaterials are constructed with ‘flute-like’ acoustic meta-cluster sets with seven double meta-molecules; these metamaterials also overcome the limitations of broadband negative bulk modulus and mass density to provide a region of negative refraction and inverse Doppler effects. It was also shown that inverse Doppler effects can be detected in a flute, which has been popular for thousands of years in Asia and Europe.
Intelligent inversion method for pre-stack seismic big data based on MapReduce
NASA Astrophysics Data System (ADS)
Yan, Xuesong; Zhu, Zhixin; Wu, Qinghua
2018-01-01
Seismic exploration is a method of oil exploration that uses seismic information; that is, according to the inversion of seismic information, the useful information of the reservoir parameters can be obtained to carry out exploration effectively. Pre-stack data are characterised by a large amount of data, abundant information, and so on, and according to its inversion, the abundant information of the reservoir parameters can be obtained. Owing to the large amount of pre-stack seismic data, existing single-machine environments have not been able to meet the computational needs of the huge amount of data; thus, the development of a method with a high efficiency and the speed to solve the inversion problem of pre-stack seismic data is urgently needed. The optimisation of the elastic parameters by using a genetic algorithm easily falls into a local optimum, which results in a non-obvious inversion effect, especially for the optimisation effect of the density. Therefore, an intelligent optimisation algorithm is proposed in this paper and used for the elastic parameter inversion of pre-stack seismic data. This algorithm improves the population initialisation strategy by using the Gardner formula and the genetic operation of the algorithm, and the improved algorithm obtains better inversion results when carrying out a model test with logging data. All of the elastic parameters obtained by inversion and the logging curve of theoretical model are fitted well, which effectively improves the inversion precision of the density. This algorithm was implemented with a MapReduce model to solve the seismic big data inversion problem. The experimental results show that the parallel model can effectively reduce the running time of the algorithm.
Efficacy of an ankle brace with a subtalar locking system in inversion control in dynamic movements.
Zhang, Songning; Wortley, Michael; Chen, Qingjian; Freedman, Julia
2009-12-01
Controlled laboratory study. To examine effectiveness of an ankle brace with a subtalar locking system in restricting ankle inversion during passive and dynamic movements. Semirigid ankle braces are considered more effective in restricting ankle inversion than other types of brace, but a semirigid brace with a subtalar locking system may be even more effective. Nineteen healthy subjects with no history of major lower extremity injuries were included in the study. Participants performed 5 trials of an ankle inversion drop test and a lateral-cutting movement without wearing a brace and while wearing either the Element (with the subtalar locking system), a Functional ankle brace, or an ASO ankle brace. A 2-way repeated-measures analysis of variance (ANOVA) was used to assess brace differences (P?.05). All 3 braces significantly reduced total passive ankle frontal plane range of motion (ROM), with the Element ankle brace being the most effective. For the inversion drop the results showed significant reductions in peak ankle inversion angle and inversion ROM for all 3 braces compared to the no brace condition; and the peak inversion velocity was also reduced for the Element brace and the Functional brace. In the lateral-cutting movement, a small but significant reduction of the peak inversion angle in early foot contact and the peak eversion velocity at push-off were seen when wearing the Element and the Functional ankle braces compared to the no brace condition. Peak vertical ground reaction force was reduced for the Element brace compared to the ASO brace and the no brace conditions. These results suggest that the tested ankle braces, especially the Element brace, provided effective restriction of ankle inversion during both passive and dynamic movements.
Recombination rate predicts inversion size in Diptera.
Cáceres, M; Barbadilla, A; Ruiz, A
1999-01-01
Most species of the Drosophila genus and other Diptera are polymorphic for paracentric inversions. A common observation is that successful inversions are of intermediate size. We test here the hypothesis that the selected property is the recombination length of inversions, not their physical length. If so, physical length of successful inversions should be negatively correlated with recombination rate across species. This prediction was tested by a comprehensive statistical analysis of inversion size and recombination map length in 12 Diptera species for which appropriate data are available. We found that (1) there is a wide variation in recombination map length among species; (2) physical length of successful inversions varies greatly among species and is inversely correlated with the species recombination map length; and (3) neither the among-species variation in inversion length nor the correlation are observed in unsuccessful inversions. The clear differences between successful and unsuccessful inversions point to natural selection as the most likely explanation for our results. Presumably the selective advantage of an inversion increases with its length, but so does its detrimental effect on fertility due to double crossovers. Our analysis provides the strongest and most extensive evidence in favor of the notion that the adaptive value of inversions stems from their effect on recombination. PMID:10471710
The inverse skin effect in the Z-pinch and plasma focus
DOE Office of Scientific and Technical Information (OSTI.GOV)
Usenko, P. L., E-mail: otd4@expd.vniief.ru; Gaganov, V. V.
The inverse skin effect and its influence on the dynamics of high-current Z-pinch and plasma focus discharges in deuterium are analyzed. It is shown that the second compression responsible for the major fraction of the neutron yield can be interpreted as a result of the inverse skin effect resulting in the axial concentration of the longitudinal current density and the appearance of a reversed current in the outer layers of plasma pinches. Possible conditions leading to the enhancement of the inverse skin effect and accessible for experimental verification by modern diagnostics are formulated.
Attention Priority Map of Face Images in Human Early Visual Cortex.
Mo, Ce; He, Dongjun; Fang, Fang
2018-01-03
Attention priority maps are topographic representations that are used for attention selection and guidance of task-related behavior during visual processing. Previous studies have identified attention priority maps of simple artificial stimuli in multiple cortical and subcortical areas, but investigating neural correlates of priority maps of natural stimuli is complicated by the complexity of their spatial structure and the difficulty of behaviorally characterizing their priority map. To overcome these challenges, we reconstructed the topographic representations of upright/inverted face images from fMRI BOLD signals in human early visual areas primary visual cortex (V1) and the extrastriate cortex (V2 and V3) based on a voxelwise population receptive field model. We characterized the priority map behaviorally as the first saccadic eye movement pattern when subjects performed a face-matching task relative to the condition in which subjects performed a phase-scrambled face-matching task. We found that the differential first saccadic eye movement pattern between upright/inverted and scrambled faces could be predicted from the reconstructed topographic representations in V1-V3 in humans of either sex. The coupling between the reconstructed representation and the eye movement pattern increased from V1 to V2/3 for the upright faces, whereas no such effect was found for the inverted faces. Moreover, face inversion modulated the coupling in V2/3, but not in V1. Our findings provide new evidence for priority maps of natural stimuli in early visual areas and extend traditional attention priority map theories by revealing another critical factor that affects priority maps in extrastriate cortex in addition to physical salience and task goal relevance: image configuration. SIGNIFICANCE STATEMENT Prominent theories of attention posit that attention sampling of visual information is mediated by a series of interacting topographic representations of visual space known as attention priority maps. Until now, neural evidence of attention priority maps has been limited to studies involving simple artificial stimuli and much remains unknown about the neural correlates of priority maps of natural stimuli. Here, we show that attention priority maps of face stimuli could be found in primary visual cortex (V1) and the extrastriate cortex (V2 and V3). Moreover, representations in extrastriate visual areas are strongly modulated by image configuration. These findings extend our understanding of attention priority maps significantly by showing that they are modulated, not only by physical salience and task-goal relevance, but also by the configuration of stimuli images. Copyright © 2018 the authors 0270-6474/18/380149-09$15.00/0.
Universal inverse design of surfaces with thin nematic elastomer sheets.
Aharoni, Hillel; Xia, Yu; Zhang, Xinyue; Kamien, Randall D; Yang, Shu
2018-06-21
Programmable shape-shifting materials can take different physical forms to achieve multifunctionality in a dynamic and controllable manner. Although morphing a shape from 2D to 3D via programmed inhomogeneous local deformations has been demonstrated in various ways, the inverse problem-finding how to program a sheet in order for it to take an arbitrary desired 3D shape-is much harder yet critical to realize specific functions. Here, we address this inverse problem in thin liquid crystal elastomer (LCE) sheets, where the shape is preprogrammed by precise and local control of the molecular orientation of the liquid crystal monomers. We show how blueprints for arbitrary surface geometries can be generated using approximate numerical methods and how local extrinsic curvatures can be generated to assist in properly converting these geometries into shapes. Backed by faithfully alignable and rapidly lockable LCE chemistry, we precisely embed our designs in LCE sheets using advanced top-down microfabrication techniques. We thus successfully produce flat sheets that, upon thermal activation, take an arbitrary desired shape, such as a face. The general design principles presented here for creating an arbitrary 3D shape will allow for exploration of unmet needs in flexible electronics, metamaterials, aerospace and medical devices, and more.
Inverse opal photonic crystals with photonic band gaps in the visible and near-infrared
NASA Astrophysics Data System (ADS)
Jarvis, Brandon C.; Gilleland, Cody L.; Renfro, Tim; Gutierrez, Jose; Parikh, Kunjal; Glosser, R.; Landon, Preston B.
2005-08-01
Colloidal silica spheres with 200nm, 250nm, and 290nm diameters were self-assembled with single crystal crystallites 4-5mm wide and 10-15mm long. Larger spheres with diameters between 1000-2300nm were self-assembled with single crystal crystallites up to 1.5mm wide and 2mm long. The silica opals self-assembled vertically along the [100] direction of the face centered cubic lattice resulting in self-templated opals. Inverse opal photonic crystals with a partial band gap possessing a maximum in the near infrared at 3.8μm were constructed from opal templates composed of 2300nm diameter spheres with chalcogenide Ge33As12Se55 (AMTIR-1), a transparent glass in the near infrared with high refractive index. Inverse gold and gold/ polypropylene composite photonic crystals were fabricated from synthetic opal templates composed of 200-290nm silica spheres. The reflectance spectra and electrical conductance of the resulting structures is presented. Gold was infiltrated into opal templates as gold chloride and heat converted to metallic gold. Opals partially infiltrated with gold were co-infiltrated with polypropylene plastic for mechanical support prior to removal of the silica template with hydrofluoric acid.
Stoica, Grigoreta M.; Stoica, Alexandru Dan; An, Ke; ...
2014-11-28
The problem of calculating the inverse pole figure (IPF) is analyzed from the perspective of the application of time-of flight neutron diffraction toin situmonitoring of the thermomechanical behavior of engineering materials. On the basis of a quasi-Monte Carlo (QMC) method, a consistent set of grain orientations is generated and used to compute the weighting factors for IPF normalization. The weighting factors are instrument dependent and were calculated for the engineering materials diffractometer VULCAN (Spallation Neutron Source, Oak Ridge National Laboratory). The QMC method is applied to face-centered cubic structures and can be easily extended to other crystallographic symmetries. Examples includemore » 316LN stainless steelin situloaded in tension at room temperature and an Al–2%Mg alloy, substantially deformed by cold rolling and in situannealed up to 653 K.« less
The First Time Ever I Saw Your Feet: Inversion Effect in Newborns' Sensitivity to Biological Motion
ERIC Educational Resources Information Center
Bardi, Lara; Regolin, Lucia; Simion, Francesca
2014-01-01
Inversion effect in biological motion perception has been recently attributed to an innate sensitivity of the visual system to the gravity-dependent dynamic of the motion. However, the specific cues that determine the inversion effect in naïve subjects were never investigated. In the present study, we have assessed the contribution of the local…
Seeing the world topsy-turvy: The primary role of kinematics in biological motion inversion effects.
Fitzgerald, Sue-Anne; Brooks, Anna; van der Zwan, Rick; Blair, Duncan
2014-01-01
Physical inversion of whole or partial human body representations typically has catastrophic consequences on the observer's ability to perform visual processing tasks. Explanations usually focus on the effects of inversion on the visual system's ability to exploit configural or structural relationships, but more recently have also implicated motion or kinematic cue processing. Here, we systematically tested the role of both on perceptions of sex from upright and inverted point-light walkers. Our data suggest that inversion results in systematic degradations of the processing of kinematic cues. Specifically and intriguingly, they reveal sex-based kinematic differences: Kinematics characteristic of females generally are resistant to inversion effects, while those of males drive systematic sex misperceptions. Implications of the findings are discussed.
Fu, Weijie; Fang, Ying; Liu, Yu; Hou, Jianfu
2014-02-18
There is still uncertainty concerning the beneficial effects of shoe collar height for ankle sprain prevention and very few data are available in the literature regarding the effect of high-top and low-top shoes on muscle responses during landing. The purpose of this study was to quantify the effect of high-top and low-top shoes on ankle inversion kinematics and pre-landing EMG activation of ankle evertor muscles during landing on a tilted surface. Thirteen physical education students landed on four types of surfaces wearing either high-top shoes (HS) or low-top shoes (LS). The four conditions were 15° inversion, 30° inversion, combined 25° inversion + 10° plantar flexion, and combined 25° inversion + 20° plantar flexion. Ankle inversion kinematics and EMG data of the tibialis anterior (TA), peroneus longus (PL), and peroneus brevis (PB) muscles were measured simultaneously. A 2 × 4 (shoe × surface) repeated measures ANOVA was performed to examine the effect of shoe and landing surfaces on ankle inversion and EMG responses. No significant differences were observed between the various types of shoes in the maximum ankle inversion angle, the ankle inversion range of motion, and the maximum ankle inversion angular velocity after foot contact for all conditions. However, the onset time of TA and PB muscles was significantly later wearing HS compared to LS for the 15° inversion condition. Meanwhile, the mean amplitude of the integrated EMG from the 50 ms prior to contact (aEMGpre) of TA was significantly lower with HS compared to LS for the 15° inversion condition and the combined 25° inversion + 20° plantarflexion condition. Similarly, the aEMGpre when wearing HS compared to LS also showed a 37.2% decrease in PL and a 31.0% decrease in PB for the combined 25° inversion + 20° plantarflexion condition and the 15° inversion condition, respectively. These findings provide preliminary evidence suggesting that wearing high-top shoes can, in certain conditions, induce a delayed pre-activation timing and decreased amplitude of evertor muscle activity, and may therefore have a detrimental effect on establishing and maintaining functional ankle joint stability.
The Inversion Effect for Chinese Characters is Modulated by Radical Organization.
Luo, Canhuang; Chen, Wei; Zhang, Ye
2017-06-01
In studies of visual object recognition, strong inversion effects accompany the acquisition of expertise and imply the involvement of configural processing. Chinese literacy results in sensitivity to the orthography of Chinese characters. While there is some evidence that this orthographic sensitivity results in an inversion effect, and thus involves configural processing, that processing might depend on exact orthographic properties. Chinese character recognition is believed to involve a hierarchical process, involving at least two lower levels of representation: strokes and radicals. Radicals are grouped into characters according to certain types of structure, i.e. left-right structure, top-bottom structure, or simple characters with only one radical by itself. These types of radical structures vary in both familiarity, and in hierarchical level (compound versus simple characters). In this study, we investigate whether the hierarchical-level or familiarity of radical-structure has an impact on the magnitude of the inversion effect. Participants were asked to do a matching task on pairs of either upright or inverted characters with all the types of structure. Inversion effects were measured based on both reaction time and response sensitivity. While an inversion effect was observed in all 3 conditions, the magnitude of the inversion effect varied with radical structure, being significantly larger for the most familiar type of structure: characters consisting of 2 radicals organized from left to right. These findings indicate that character recognition involves extraction of configural structure as well as radical processing which play different roles in the processing of compound characters and simple characters.
Perez, Lilian G; Arredondo, Elva M; McKenzie, Thomas L; Holguin, Margarita; Elder, John P; Ayala, Guadalupe X
2015-10-01
Greater neighborhood social cohesion is linked to fewer depressive symptoms and greater physical activity, but the role of physical activity on the relationship between neighborhood social cohesion and depression is poorly understood. The purpose of the study was to examine the effects of physical activity on the association between neighborhood social cohesion and depressive symptoms. Multivariate logistic regression tested the moderation of self-reported leisure-time moderate-to-vigorous physical activity (LTMVPA) and active use of parks or recreational facilities on the association between neighborhood social cohesion and depressive symptoms among 295 randomly selected Latino adults who completed a face-to-face interview. After adjusting for age, gender, and income, neighborhood social cohesion and depressive symptoms were inversely related (OR = 0.8; 95% CI: 0.5-1.2). Active use of parks or recreational facilities moderated the association between neighborhood social cohesion and depressive symptoms but meeting the recommendations for LTMVPA did not. Latinos who reported active use of parks or recreational facilities and higher levels of neighborhood social cohesion had fewer depressive symptoms than peers who did not use these spaces. Future studies are needed to test strategies for promoting active use of parks or recreational facilities to address depression in Latinos.
Perez, Lilian G.; Arredondo, Elva M.; McKenzie, Thomas L.; Holguin, Margarita; Elder, John P.; Ayala, Guadalupe X.
2017-01-01
Background Greater neighborhood social cohesion is linked to fewer depressive symptoms and greater physical activity, but the role of physical activity on the relationship between neighborhood social cohesion and depression is poorly understood. The purpose of the study was to examine the effects of physical activity on the association between neighborhood social cohesion and depressive symptoms. Methods Multivariate logistic regression tested the moderation of self-reported leisure time moderate-to vigorous-physical activity (LTMVPA) and active use of parks or recreational facilities on the association between neighborhood social cohesion and depressive symptoms among 295 randomly selected Latino adults who completed a face-to-face interview. Results After adjusting for age, gender, and income, neighborhood social cohesion and depressive symptoms were inversely related (OR=0.8; 95% CI: 0.5–1.2). Active use of parks or recreational facilities moderated the association between neighborhood social cohesion and depressive symptoms but meeting the recommendations for LTMVPA did not. Latinos who reported active use of parks or recreational facilities and higher levels of neighborhood social cohesion had fewer depressive symptoms than peers who did not use these spaces. Conclusions Future studies are needed to test strategies for promoting active use of parks or recreational facilities to address depression in Latinos. PMID:25599244
From Agents to Objects: Sexist Attitudes and Neural Responses to Sexualized Targets
Cikara, Mina; Eberhardt, Jennifer L.; Fiske, Susan T.
2013-01-01
Agency attribution is a hallmark of mind perception; thus, diminished attributions of agency may disrupt social-cognition processes typically elicited by human targets. The current studies examine the effect of perceivers’ sexist attitudes on associations of agency with, and neural responses to, images of sexualized and clothed men and women. In study 1, male (but not female) participants with higher hostile sexism scores more quickly associated sexualized women with first-person action verbs (“handle”) and clothed women with third-person action verbs (“handles”) than the inverse, as compared to their less sexist peers. In study 2, hostile sexism correlated negatively with activation of regions associated with mental state attribution—mPFC, posterior cingulate, temporal poles—but only when viewing sexualized women. Heterosexual men best recognized images of sexualized female bodies (but not faces), as compared with other targets’ bodies; however, neither face nor body recognition were related to hostile sexism, suggesting the fMRI findings are not explained by more or less attention to sexualized female targets. Diminished mental-state attribution is not unique to targets that people prefer to avoid, as in dehumanization of stigmatized people. The current studies demonstrate that appetitive social targets may elicit a similar response depending on perceivers’ attitudes toward them. PMID:20350187
Schielzeth, Holger; Rios Villamil, Alejandro; Burri, Reto
2018-03-25
Recent developments in sequencing technologies have facilitated genomewide mapping of phenotypic variation in natural populations. Such mapping efforts face a number of challenges potentially leading to low reproducibility. However, reproducible research forms the basis of scientific progress. We here discuss the options for replication and the reasons for potential nonreproducibility. We then review the evidence for reproducible quantitative trait loci (QTL) with a focus on natural animal populations. Existing case studies of replication fall into three categories: (i) traits that have been mapped to major effect loci (including chromosomal inversion and supergenes) by independent research teams; (ii) QTL fine-mapped in discovery populations; and (iii) attempts to replicate QTL across multiple populations. Major effect loci, in particular those associated with inversions, have been successfully replicated in several cases within and across populations. Beyond such major effect variants, replication has been more successful within than across populations, suggesting that QTL discovered in natural populations may often be population-specific. This suggests that biological causes (differences in linkage patterns, allele frequencies or context-dependencies of QTL) contribute to nonreproducibility. Evidence from other fields, notably animal breeding and QTL mapping in humans, suggests that a significant fraction of QTL is indeed reproducible in direction and magnitude at least within populations. However, there is also a large number of QTL that cannot be easily reproduced. We put forward that more studies should explicitly address the causes and context-dependencies of QTL signals, in particular to disentangle linkage differences, allele frequency differences and gene-by-environment interactions as biological causes of nonreproducibility of QTL, especially between populations. © 2018 John Wiley & Sons Ltd.
Incorporating social anxiety into a model of college student problematic drinking
Ham, Lindsay S.; Hope, Debra A.
2009-01-01
College problem drinking and social anxiety are significant public health concerns with highly negative consequences. College students are faced with a variety of novel social situations and situations encouraging alcohol consumption. The current study involved developing a path model of college problem drinking, including social anxiety, in 316 college students referred to an alcohol intervention due to a campus alcohol violation. Contrary to hypotheses, social anxiety generally had an inverse relationship with problem drinking. As expected, perceived drinking norms had important positive, direct effects on drinking variables. However, the results generally did not support the hypotheses regarding the mediating or moderating function of the valuations of expected effects and provided little support for the mediating function of alcohol expectancies in the relations among social anxiety and alcohol variables. Therefore, it seems that the influence of peers may be more important for college students than alcohol expectancies and valuations of alcohol’s effects are. College students appear to be a unique population in respect to social anxiety and problem drinking. The implications of these results for college prevention and intervention programs were discussed. PMID:15561454
SU-E-T-459: Impact of Source Position and Traveling Time On HDR Skin Surface Applicator Dosimetry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeong, J; Barker, C; Zaider, M
Purpose: Observed dosimetric discrepancy between measured and treatment planning system (TPS) predicted values, during applicator commissioning, were traced to source position uncertainty in the applicator. We quantify the dosimetric impact of this geometric uncertainty, and of the source traveling time inside the applicator, and propose corrections for clinical use. Methods: We measured the dose profiles from the Varian Leipzig-style (horizontal) HDR skin applicator, using EBT3 film, photon diode, and optically stimulated luminescence dosimeter (OSLD) and three different GammaMed HDR afterloders. The dose profiles and depth dose of each aperture were measured at several depths (up to about 10 mm, dependingmore » on the dosimeter). The measured dose profiles were compared with Acuros calculated profiles in BrachyVision TPS. For the impact of the source position, EBT3 film measurements were performed with applicator, facing-down and facing-up orientations. The dose with and without source traveling was measured with diode detector using HDR timer and electrometer timer, respectively. Results: Depth doses measured using the three dosimeters were in good agreement, but were consistently higher than the Acuros dose calculations. Measurements with the applicator facing-up were significantly lower than those in the facing-down position with maximum difference of about 18% at the surface, due to source sag inside the applicator. Based on the inverse-square law, the effective source sag was evaluated to be about 0.5 mm from the planned position. The additional dose from the source traveling was about 2.8% for 30 seconds with 10 Ci source, decreasing with increased dwelling time and decreased source activity. Conclusion: Due to the short source-to-surface distance of the applicator, the small source sag inside the applicator has significant dosimetric impact, which should be considered before the clinical use of the applicator. Investigation of the effect for other applicators that have relatively large source lumen inner diameter may be warranted. Christopher Barker and Gil’ad Cohen are receiving research support for a study of skin surface brachytherapy from Elekta.« less
2D joint inversion of CSAMT and magnetic data based on cross-gradient theory
NASA Astrophysics Data System (ADS)
Wang, Kun-Peng; Tan, Han-Dong; Wang, Tao
2017-06-01
A two-dimensional forward and backward algorithm for the controlled-source audio-frequency magnetotelluric (CSAMT) method is developed to invert data in the entire region (near, transition, and far) and deal with the effects of artificial sources. First, a regularization factor is introduced in the 2D magnetic inversion, and the magnetic susceptibility is updated in logarithmic form so that the inversion magnetic susceptibility is always positive. Second, the joint inversion of the CSAMT and magnetic methods is completed with the introduction of the cross gradient. By searching for the weight of the cross-gradient term in the objective function, the mutual influence between two different physical properties at different locations are avoided. Model tests show that the joint inversion based on cross-gradient theory offers better results than the single-method inversion. The 2D forward and inverse algorithm for CSAMT with source can effectively deal with artificial sources and ensures the reliability of the final joint inversion algorithm.
NASA Technical Reports Server (NTRS)
Hartung, J. B.
1984-01-01
The Moon's center of mass is displaced from its center of figure about 2 km in a roughly earthward direction. Most maria are on the side of the Moon which faces the Earth. It is assumed that the Moon was initially spherically symmetric. The emplacement of mare basalts transfers mass which produces most of the observed center of mass displacement toward the Earth. The cause of the asymmetric distribution of lunar maria was examined. The Moon is in a spin orbit coupled relationship with the Earth and the effect of the Earth's gravity on the Moon is asymmetric. The earth-facing side of the Moon is a gravitational favored location for the extrusion of mare basalt magma in the same way that the topographically lower floor of a large impact basin is a gravitationally favored location. This asymmetric effect increases inversely with the fourth power of the Earth Moon distance. The history of the Earth-Moon system includes: formation of the Moon by accretion processes in a heliocentric orbit ner that of the Earth; a gravitational encounter with the Earth about 4 billion years ago resulting in capture of the Moon into a geocentric orbit and heating of the Moon through dissipation of energy related to tides raised during close approaches to the Earth(5) to produce mare basalt magma; and evolution of the Moon's orbit to its present position, slowly at first to accommodate more than 500 million years during which magmas were extruded.
Scott, Kate M.; Al-Hamzawi, Ali Obaid; Andrade, Laura H.; Borges, Guilherme; Caldas-de-Almeida, Jose Miguel; Fiestas, Fabian; Gureje, Oye; Hu, Chiyi; Karam, Elie G.; Kawakami, Norito; Lee, Sing; Levinson, Daphna; Lim, Carmen C.W.; Navarro-Mateu, Fernando; Okoliyski, Michail; Posada-Villa, Jose; Torres, Yolanda; Williams, David R.; Zakhozha, Victoria; Kessler, Ronald C.
2017-01-01
Importance The inverse social gradient in mental disorders is a well-established research finding with important implications for causal models and policy. This research has used traditional objective social status (OSS) measures such as education, income and occupation. Recently, subjective social status (SSS) measurement has been advocated to capture perception of relative social status, but to date there are no studies of associations between SSS and mental disorders. Objective To estimate associations of SSS with DSM-IV mental disorders in multiple countries and to investigate whether the associations persist after comprehensive adjustment of OSS. Design; Setting; Participants Face-to-face cross-sectional household surveys of community-dwelling adults in 18 countries in Asia, South Pacific, the Americas, Europe, the Middle East (n= 56,085). SSS was assessed with a self-anchoring scale reflecting respondent evaluations of their place in the social hierarchies of their countries in terms of income, education and occupation. Scores on the 1–10 SSS scale were categorised into four categories: low (scores 1–3); low-mid (scores 4 and 5); high-mid (scores 6 and 7); high (scores 8–10). OSS was assessed with a wide range of fine-grained objective indicators of income, education and occupation. Main Outcome Measures The Composite International Diagnostic Interview assessed 12-month prevalence of 16 DSM-IV mood, anxiety and impulse control disorders. Results Graded, inverse associations were found between SSS and all 16 mental disorders. Gross odds-ratios (lowest versus highest SSS categories) in the range 1.8–9.0 were attenuated but remained significant for all 16 disorders (ORs: 1.4–4.9) after adjusting for OSS indicators. The pattern of inverse association between SSS and mental disorders was significant in 14/18 individual countries, and in low, middle and high income country groups, but was significantly stronger in higher versus lower income countries. Conclusions Significant inverse associations between SSS and numerous DSM-IV mental disorders exist across a wide range of countries even after comprehensive adjustment for OSS. Although unclear whether these associations are due to social selection, social causation, or both, these results document clearly that research relying exclusively on standard OSS measures underestimates the steepness of the social gradient in mental disorders. PMID:25354080
Seeing the world topsy-turvy: The primary role of kinematics in biological motion inversion effects
Fitzgerald, Sue-Anne; Brooks, Anna; van der Zwan, Rick; Blair, Duncan
2014-01-01
Physical inversion of whole or partial human body representations typically has catastrophic consequences on the observer's ability to perform visual processing tasks. Explanations usually focus on the effects of inversion on the visual system's ability to exploit configural or structural relationships, but more recently have also implicated motion or kinematic cue processing. Here, we systematically tested the role of both on perceptions of sex from upright and inverted point-light walkers. Our data suggest that inversion results in systematic degradations of the processing of kinematic cues. Specifically and intriguingly, they reveal sex-based kinematic differences: Kinematics characteristic of females generally are resistant to inversion effects, while those of males drive systematic sex misperceptions. Implications of the findings are discussed. PMID:25469217
Inversion of time-domain induced polarization data based on time-lapse concept
NASA Astrophysics Data System (ADS)
Kim, Bitnarae; Nam, Myung Jin; Kim, Hee Joon
2018-05-01
Induced polarization (IP) surveys, measuring overvoltage phenomena of the medium, are widely and increasingly performed not only for exploration of mineral resources but also for engineering applications. Among several IP survey methods such as time-domain, frequency-domain and spectral IP surveys, this study introduces a noble inversion method for time-domain IP data to recover the chargeability structure of target medium. The inversion method employs the concept of 4D inversion of time-lapse resistivity data sets, considering the fact that measured voltage in time-domain IP survey is distorted by IP effects to increase from the instantaneous voltage measured at the moment the source current injection starts. Even though the increase is saturated very fast, we can consider the saturated and instantaneous voltages as a time-lapse data set. The 4D inversion method is one of the most powerful method for inverting time-lapse resistivity data sets. Using the developed IP inversion algorithm, we invert not only synthetic but also field IP data to show the effectiveness of the proposed method by comparing the recovered chargeability models with those from linear inversion that was used for the inversion of the field data in a previous study. Numerical results confirm that the proposed inversion method generates reliable chargeability models even though the anomalous bodies have large IP effects.
Pedrocchi, Alessandra; Pedotti, Antonio; Baroni, Guido; Massion, Jean; Ferrigno, Giancarlo
2003-11-01
Present investigation faces the question of quantitative assessment of exchanged forces and torques at the restraints during whole body posture exercises in long-term microgravity. Inverse dynamic modelling and total angular momentum at the ankle joint were used in order to reconstruct movement dynamics at the restraining point, represented by the ankle joint. The hypothesis is that the minimisation of the torques at the interface point assumes a key role in movement planning in 0 g. This hypothesis would respond to an optimisation of muscles activity, a minimisation of energy expenditure and therefore an accurate control of body movement. Results show that the 0 g movement strategy adopted ensures that the integral of the net ankle moment between the beginning and the end of the movement is zero. This expected mechanical constraint is not satisfied when 0 g movement dynamics is simulated using terrestrial kinematics. This accounts for a significant imposed change of movement strategy. Particularly, the efficient compensation of the inertial effects of the segments in terms of total angular momentum at the ankle joint was evidenced. These results explain the exaggerated axial synergies, observed on kinematics and which moved centre of mass (CM) backward from its already backward initial positioning, as a tool for enhancing the compensation and achieving the desired minimisation of the torques exchanges at the restraints.
Inverse Opal Photonic Crystals as an Optofluidic Platform for Fast Analysis of Hydrocarbon Mixtures.
Xu, Qiwei; Mahpeykar, Seyed Milad; Burgess, Ian B; Wang, Xihua
2018-06-13
Most of the reported optofluidic devices analyze liquid by measuring its refractive index. Recently, the wettability of liquid on various substrates has also been used as a key sensing parameter in optofluidic sensors. However, the above-mentioned techniques face challenges in the analysis of the relative concentration of components in an alkane hydrocarbon mixture, as both refractive indices and wettabilities of alkane hydrocarbons are very close. Here, we propose to apply volatility of liquid as the key sensing parameter, correlate it to the optical property of liquid inside inverse opal photonic crystals, and construct powerful optofluidic sensors for alkane hydrocarbon identification and analysis. We have demonstrated that via evaporation of hydrocarbons inside the periodic structure of inverse opal photonic crystals and observation of their reflection spectra, an inverse opal film could be used as a fast-response optofluidic sensor to accurately differentiate pure hydrocarbon liquids and relative concentrations of their binary and ternary mixtures in tens of seconds. In these 3D photonic crystals, pure chemicals with different volatilities would have different evaporation rates and can be easily identified via the total drying time. For multicomponent mixtures, the same strategy is applied to determine the relative concentration of each component simply by measuring drying time under different temperatures. Using this optofluidic sensing platform, we have determined the relative concentrations of ternary hydrocarbon mixtures with the difference of only one carbon between alkane hydrocarbons, which is a big step toward detailed hydrocarbon analysis for practical use.
Kerrigan, Deanna; Vazzano, Andrea; Bertoni, Neilane; Malta, Monica; Bastos, Francisco Inacio
2017-02-01
Limited research has examined the social context surrounding stigma and discrimination and HIV outcomes among people living with HIV (PLHIV). We surveyed 900 PLHIV in Brazil and examined the relationship between stigma, discrimination and HIV outcomes utilising multivariable logistic regression. HIV stigma and discrimination were inversely associated with age (AOR Stigma 0.65, 95% CI 0.49-0.88; AOR Discrimination 0.72, 95% CI 0.54-0.95) and income (AOR Stigma 0.74, 95% CI 0.55-0.99; AOR Discrimination 0.62, 95% CI 0.46-0.82). Stigma was inversely associated with education (AOR 0.71, 95% CI 0.52-0.96) and no history of sex work (AOR 0.56, 95% CI 0.35-0.90), and positively associated with having children (AOR 1.71, 95% CI 1.18-2.48). Discrimination was inversely associated with no history of drug use (AOR 0.63, 95% CI 0.42-0.95). Stigma and discrimination were found to be inversely associated with overall health (AOR Stigma 0.54, 95% CI 0.40-0.74; AOR Discrimination 0.71, 95% CI 0.52-0.97). Discrimination was associated with having a sexually transmitted infection since HIV diagnosis (AOR 1.63, 95% CI 1.14-2.32). Findings suggest that future interventions should address multiple social inequalities faced by PLHIV to reduce HIV stigma and discrimination and improve health and HIV outcomes.
The Breakup of Temperature Inversions In Steep Valleys
NASA Astrophysics Data System (ADS)
Colette, A.; Street, R.
The purpose of this research is to model and provide a better understanding of tem- perature inversions breakup in steep valleys. The Advanced Regional Prediction Sys- tem (ARPS), a three-dimensional, compressible, and non-hydrostatic modeling tool developed by the Center for Analysis and Prediction of Storms at the University of Oklahoma was used. Many field studies indicate that the evolution of the convective and inversion layers are strongly dependant on the surrounding topography. In relatively open valleys, the convective boundary layer usually grows from the bottom of the valley while in steeper cases, the upslope morning winds affects the dynamic of the mixing layer resulting in the destruction of the inversion from its bottom and its top (see Whiteman 1980). ARPS allows one to perform accurate simulation of such situations. First, written in terrain following coordinates, it handles steep topographies; then its extensive radi- ation and surface flux packages provide a good treatment of land related processes. Moreover, ARPS accounts for the incidence angle of sunrays, differencing the ex- posed and non-exposed mountain slopes. However, it neglects the topographic shade which can delay the sunrise of a hour or more in steep valleys. A new subroutine described by Colette etal. 2002 is thus used to compute the projected shade on the surrounding topography. Simulations of temperature inversion breakup for various two-dimensional valleys are presented. The time scale of evolution of the mixing layer is in good agreement with field studies and, as expected, the convective boundary layer shows an asymmetry between east and west facing slopes. The different patterns of inversion breakup doc- umented by Whiteman are also reproduced. These simulations of idealized cases give a better understanding of inversion breakup in steep valleys. Our code is now being applied to a real case: the study of a peculiar wind, la Ora del Garda, caused by the interaction between a lake breeze and a valley wind in the Garda Valley (Northern Italy). Preliminary simulations will be presented. The support of AC by TotalFinaElf and RS by the Physical Meteorology Program of NSF and the VTMX Program of DoE is appreciated.
Van Regenmortel, Marc H. V.
2018-01-01
Hypotheses and theories are essential constituents of the scientific method. Many vaccinologists are unaware that the problems they try to solve are mostly inverse problems that consist in imagining what could bring about a desired outcome. An inverse problem starts with the result and tries to guess what are the multiple causes that could have produced it. Compared to the usual direct scientific problems that start with the causes and derive or calculate the results using deductive reasoning and known mechanisms, solving an inverse problem uses a less reliable inductive approach and requires the development of a theoretical model that may have different solutions or none at all. Unsuccessful attempts to solve inverse problems in HIV vaccinology by reductionist methods, systems biology and structure-based reverse vaccinology are described. The popular strategy known as rational vaccine design is unable to solve the multiple inverse problems faced by HIV vaccine developers. The term “rational” is derived from “rational drug design” which uses the 3D structure of a biological target for designing molecules that will selectively bind to it and inhibit its biological activity. In vaccine design, however, the word “rational” simply means that the investigator is concentrating on parts of the system for which molecular information is available. The economist and Nobel laureate Herbert Simon introduced the concept of “bounded rationality” to explain why the complexity of the world economic system makes it impossible, for instance, to predict an event like the financial crash of 2007–2008. Humans always operate under unavoidable constraints such as insufficient information, a limited capacity to process huge amounts of data and a limited amount of time available to reach a decision. Such limitations always prevent us from achieving the complete understanding and optimization of a complex system that would be needed to achieve a truly rational design process. This is why the complexity of the human immune system prevents us from rationally designing an HIV vaccine by solving inverse problems. PMID:29387066
Estimating uncertainty of Full Waveform Inversion with Ensemble-based methods
NASA Astrophysics Data System (ADS)
Thurin, J.; Brossier, R.; Métivier, L.
2017-12-01
Uncertainty estimation is one key feature of tomographic applications for robust interpretation. However, this information is often missing in the frame of large scale linearized inversions, and only the results at convergence are shown, despite the ill-posed nature of the problem. This issue is common in the Full Waveform Inversion community.While few methodologies have already been proposed in the literature, standard FWI workflows do not include any systematic uncertainty quantifications methods yet, but often try to assess the result's quality through cross-comparison with other results from seismic or comparison with other geophysical data. With the development of large seismic networks/surveys, the increase in computational power and the more and more systematic application of FWI, it is crucial to tackle this problem and to propose robust and affordable workflows, in order to address the uncertainty quantification problem faced for near surface targets, crustal exploration, as well as regional and global scales.In this work (Thurin et al., 2017a,b), we propose an approach which takes advantage of the Ensemble Transform Kalman Filter (ETKF) proposed by Bishop et al., (2001), in order to estimate a low-rank approximation of the posterior covariance matrix of the FWI problem, allowing us to evaluate some uncertainty information of the solution. Instead of solving the FWI problem through a Bayesian inversion with the ETKF, we chose to combine a conventional FWI, based on local optimization, and the ETKF strategies. This scheme allows combining the efficiency of local optimization for solving large scale inverse problems and make the sampling of the local solution space possible thanks to its embarrassingly parallel property. References:Bishop, C. H., Etherton, B. J. and Majumdar, S. J., 2001. Adaptive sampling with the ensemble transform Kalman filter. Part I: Theoretical aspects. Monthly weather review, 129(3), 420-436.Thurin, J., Brossier, R. and Métivier, L. 2017,a.: Ensemble-Based Uncertainty Estimation in Full Waveform Inversion. 79th EAGE Conference and Exhibition 2017, (12 - 15 June, 2017)Thurin, J., Brossier, R. and Métivier, L. 2017,b.: An Ensemble-Transform Kalman Filter - Full Waveform Inversion scheme for Uncertainty estimation; SEG Technical Program Expanded Abstracts 2012
Dynamic propagation of symmetric Airy pulses with initial chirps in an optical fiber
NASA Astrophysics Data System (ADS)
Shi, Xiaohui; Huang, Xianwei; Deng, Yangbao; Tan, Chao; Bai, Yanfeng; Fu, Xiquan
2017-09-01
We analytically and numerically investigate the propagation dynamics of initially chirped symmetric Airy pulses in an optical fiber. The results show that the positive chirps act to promote the interference in generating a focal point on the propagation axis, while the negative chirps tend to suppress the focusing effect, as compared to conventional unchirped symmetric Airy pulses. The numerical results demonstrate that the linear propagation of chirped symmetric Airy pulses depend considerably on the chirp parameter and the primary lobe position. In the anomalous dispersion region, positively chirped symmetric Airy pulses first undergo an initial compression, and reach a foci due to the opposite acceleration, and then experience a lossy inversion transformation, and come to the opposite facing focal position. The impact of truncation coefficient and Kerr nonlinearity on the chirped symmetric Airy pulses propagation is also disclosed separately.
Robust vehicle detection in different weather conditions: Using MIPM
Menéndez, José Manuel; Jiménez, David
2018-01-01
Intelligent Transportation Systems (ITS) allow us to have high quality traffic information to reduce the risk of potentially critical situations. Conventional image-based traffic detection methods have difficulties acquiring good images due to perspective and background noise, poor lighting and weather conditions. In this paper, we propose a new method to accurately segment and track vehicles. After removing perspective using Modified Inverse Perspective Mapping (MIPM), Hough transform is applied to extract road lines and lanes. Then, Gaussian Mixture Models (GMM) are used to segment moving objects and to tackle car shadow effects, we apply a chromacity-based strategy. Finally, performance is evaluated through three different video benchmarks: own recorded videos in Madrid and Tehran (with different weather conditions at urban and interurban areas); and two well-known public datasets (KITTI and DETRAC). Our results indicate that the proposed algorithms are robust, and more accurate compared to others, especially when facing occlusions, lighting variations and weather conditions. PMID:29513664
Internal model of gravity influences configural body processing.
Barra, Julien; Senot, Patrice; Auclair, Laurent
2017-01-01
Human bodies are processed by a configural processing mechanism. Evidence supporting this claim is the body inversion effect, in which inversion impairs recognition of bodies more than other objects. Biomechanical configuration, as well as both visual and embodied expertise, has been demonstrated to play an important role in this effect. Nevertheless, the important factor of body inversion effect may also be linked to gravity orientation since gravity is one of the most fundamental constraints of our biology, behavior, and perception on Earth. The visual presentation of an inverted body in a typical body inversion paradigm turns the observed body upside down but also inverts the implicit direction of visual gravity in the scene. The orientation of visual gravity is then in conflict with the direction of actual gravity and may influence configural processing. To test this hypothesis, we dissociated the orientations of the body and of visual gravity by manipulating body posture. In a pretest we showed that it was possible to turn an avatar upside down (inversion relative to retinal coordinates) without inverting the orientation of visual gravity when the avatar stands on his/her hands. We compared the inversion effect in typical conditions (with gravity conflict when the avatar is upside down) to the inversion effect in conditions with no conflict between visual and physical gravity. The results of our experiment revealed that the inversion effect, as measured by both error rate and reaction time, was strongly reduced when there was no gravity conflict. Our results suggest that when an observed body is upside down (inversion relative to participants' retinal coordinates) but the orientation of visual gravity is not, configural processing of bodies might still be possible. In this paper, we discuss the implications of an internal model of gravity in the configural processing of observed bodies. Copyright © 2016 Elsevier B.V. All rights reserved.
Zagami, Roberto; Romeo, Andrea; Castriciano, Maria A; Monsù Scolaro, Luigi
2017-01-01
When mixtures of D 2 O/DCl are used to foster the self-assembly formation of TPPS 4 porphyrin J-aggregates in aqueous solutions, an inverse kinetic isotope effect of 0.4 and an inverse equilibrium isotope effect of 0.6 are clearly detected. Most importantly, the addition of at least 10 % D 2 O causes an inversion in the handedness of the final chiral J-aggregates, thus evidencing an important role of deuterium in driving the enantiomeric excess in the scalemic mixture of such supramolecular assemblies. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Construction of Joule Thomson inversion curves for mixtures using equation of state
NASA Astrophysics Data System (ADS)
Patankar, A. S.; Atrey, M. D.
2017-02-01
The Joule-Thomson effect is at the heart of Joule-Thomson cryocoolers and gas liquefaction cycles. The effective harnessing of this phenomenon necessitates the knowledge of Joule-Thomson coefficient and the inversion curve. When the working fluid is a mixture, (in mix refrigerant Joule-Thomson cryocooler, MRJT) the phase diagrams, equations of state and inversion curves of multi-component systems become important. The lowest temperature attainable by such a cryocooler depends on the inversion characteristics of the mixture used. In this work the construction of differential Joule-Thomson inversion curves of mixtures using Redlich-Kwong, Soave-Redlich-Kwong and Peng-Robinson equations of state is investigated assuming single phase. It is demonstrated that inversion curves constructed for pure fluids can be improved by choosing an appropriate value of acentric factor. Inversion curves are used to predict maximum inversion temperatures of multicomponent systems. An application where this information is critical is a two-stage J-T cryocooler using a mixture as the working fluid, especially for the second stage. The pre-cooling temperature that the first stage is required to generate depends on the maximum inversion temperature of the second stage working fluid.
Effects of Inversions on Within- and Between-Species Recombination and Divergence
Stevison, Laurie S.; Hoehn, Kenneth B.; Noor, Mohamed A. F.
2011-01-01
Chromosomal inversions disrupt recombination in heterozygotes by both reducing crossing-over within inverted regions and increasing it elsewhere in the genome. The reduction of recombination in inverted regions facilitates the maintenance of hybridizing species, as outlined by various models of chromosomal speciation. We present a comprehensive comparison of the effects of inversions on recombination rates and on nucleotide divergence. Within an inversion differentiating Drosophila pseudoobscura and Drosophila persimilis, we detected one double recombinant among 9,739 progeny from F1 hybrids screened, consistent with published double-crossover frequencies observed within species. Despite similar rates of exchange within and between species, we found no sequence-based evidence of ongoing gene exchange between species within this inversion, but significant exchange was inferred within species. We also observed greater differentiation at regions near inversion breakpoints between species versus within species. Moreover, we observed strong “interchromosomal effect” (higher recombination in inversion heterozygotes between species) with up to 9-fold higher recombination rates along collinear segments of chromosome two in hybrids. Further, we observed that regions most susceptible to changes in recombination rates corresponded to regions with lower recombination rates in homokaryotypes. Finally, we showed that interspecies nucleotide divergence is lower in regions with greater increases in recombination rate, potentially resulting from greater interspecies exchange. Overall, we have identified several similarities and differences between inversions segregating within versus between species in their effects on recombination and divergence. We conclude that these differences are most likely due to lower frequency of heterokaryotypes and to fitness consequences from the accumulation of various incompatibilities between species. Additionally, we have identified possible effects of inversions on interspecies gene exchange that had not been considered previously. PMID:21828374
NASA Astrophysics Data System (ADS)
Heincke, B.; Moorkamp, M.; Jegen, M.; Hobbs, R. W.
2012-12-01
Imaging of sub-basalt sediments with reflection seismic techniques is limited due to absorption, scattering and transmission effects and the presence of peg-leg multiples. Although many of the difficulties facing conventional seismic profiles can be overcome by recording long offset data resolution of sub-basalt sediments in seismic sections is typically still largely restricted. Therefore multi-parametric approaches in general and joint inversion strategies in particular (e.g. Colombo et al., 2008, Jordan et al., 2012) are considered as alternative to gain additional information from sub-basalt structures. Here, we combine in a 3-D joint inversion first-arrival time tomography, FTG gravity and MT data to identify the base basalt and resolve potential sediments underneath. For sub-basalt exploration the three methods complement each other such that the null space is reduced and significantly better resolved models can be obtained than would be possible by the individual methods: The seismic data gives a robust model for the supra-basalt sediments whilst the gravity field is dominated by the high density basalt and basement features. The MT on the other hand is sensitive to the conductivity in both the supra- and sub-basalt sediments. We will present preliminary individual and joint inversion result for a FTG, seismic and MT data set located in the Faroe-Shetland basin. Because the investigated area is rather large (~75 x 40 km) and the individual data sets are relatively huge, we use a joint inversion framework (see Moorkamp et al., 2011) which is designed to handle large amount of data/model parameters. This program has moreover the options to link the individual parameter models either petrophysically using fixed parameter relationships or structurally using the cross-gradient approach. The seismic data set consists of a pattern of 8 intersecting wide-angle seismic profiles with maximum offsets of up to ~24 km. The 3-D gravity data set (size :~ 30 x 30 km) is collected along parallel lines by a shipborne gradiometer and the marine MT data set is composed of 41 stations that are distributed over the whole investigation area. Logging results from a borehole located in the central part of the investigation area enable us to derive parameter relationships between seismic velocities, resistivities and densities that are adequately describe the rock property behaviors of both the basaltic lava flows and sedimentary layers in this region. In addition, a 3-D reflection seismic survey covering the central part allows us to incorporate the top of basalt and other features as constraints in the joint inversions and to evaluate the quality of the final results. Literature: D. Colombo, M. Mantovani, S. Hallinan, M. Virgilio, 2008. Sub-basalt depth imaging using simultaneous joint inversion of seismic and electromagnetic (MT) data: a CRB field study. SEG Expanded Abstract, Las Vegas, USA, 2674-2678. M. Jordan, J. Ebbing, M. Brönner, J. Kamm , Z. Du, P. Eliasson, 2012. Joint Inversion for Improved Sub-salt and Sub-basalt Imaging with Application to the More Margin. EAGE Expanded Abstracts, Copenhagen, DK. M. Moorkamp, B. Heincke, M. Jegen, A.W.Roberts, R.W. Hobbs, 2011. A framework for 3-D joint inversion of MT, gravity and seismic refraction data. Geophysical Journal International, 184, 477-493.
Ju, Xiangqun; Jamieson, Lisa M; Mejia, Gloria C
2016-12-01
To estimate the effect of mothers' education on Indigenous Australian children's dental caries experience while controlling for the mediating effect of children's sweet food intake. The Longitudinal Study of Indigenous Children is a study of two representative cohorts of Indigenous Australian children, aged from 6 months to 2 years (baby cohort) and from 3.5 to 5 years (child cohort) at baseline. The children's primary caregiver undertook a face-to-face interview in 2008 and repeated annually for the next 4 years. Data included household demographics, child health (nutrition information and dental health), maternal conditions and highest qualification levels. Mother's educational level was classified into four categories: 0-9 years, 10 years, 11-12 years and >12 years. Children's mean sweet food intake was categorized as <20%, 20-30%, and >30%. After multiple imputation of missing values, a marginal structural model with stabilized inverse probability weights was used to estimate the direct effect of mothers' education level on children's dental decay experience. From 2008 to 2012, complete data on 1720 mother-child dyads were available. Dental caries experience for children was 42.3% over the 5-year period. The controlled direct effect estimates of mother's education on child dental caries were 1.21 (95% CI: 1.01-1.45), 1.03 (95% CI: 0.91-1.18) and 1.07 (95% CI: 0.93-1.22); after multiple imputation of missing values, the effects were 1.21 (95% CI: 1.05-1.39), 1.06 (95% CI: 0.94-1.19) and 1.06 (95% CI: 0.95-1.19), comparing '0-9', '10' and '11-12' years to > 12 years of education. Mothers' education level had a direct effect on children's dental decay experience that was not mediated by sweet food intake and other risk factors when estimated using a marginal structural model. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Contributions of visual and embodied expertise to body perception.
Reed, Catherine L; Nyberg, Andrew A; Grubb, Jefferson D
2012-01-01
Recent research has demonstrated that our perception of the human body differs from that of inanimate objects. This study investigated whether the visual perception of the human body differs from that of other animate bodies and, if so, whether that difference could be attributed to visual experience and/or embodied experience. To dissociate differential effects of these two types of expertise, inversion effects (recognition of inverted stimuli is slower and less accurate than recognition of upright stimuli) were compared for two types of bodies in postures that varied in typicality: humans in human postures (human-typical), humans in dog postures (human-atypical), dogs in dog postures (dog-typical), and dogs in human postures (dog-atypical). Inversion disrupts global configural processing. Relative changes in the size and presence of inversion effects reflect changes in visual processing. Both visual and embodiment expertise predict larger inversion effects for human over dog postures because we see humans more and we have experience producing human postures. However, our design that crosses body type and typicality leads to distinct predictions for visual and embodied experience. Visual expertise predicts an interaction between typicality and orientation: greater inversion effects should be found for typical over atypical postures regardless of body type. Alternatively, embodiment expertise predicts a body, typicality, and orientation interaction: larger inversion effects should be found for all human postures but only for atypical dog postures because humans can map their bodily experience onto these postures. Accuracy data supported embodiment expertise with the three-way interaction. However, response-time data supported contributions of visual expertise with larger inversion effects for typical over atypical postures. Thus, both types of expertise affect the visual perception of bodies.
Risk factors for trachoma in Mali.
Schémann, J-F; Sacko, D; Malvy, D; Momo, G; Traore, L; Bore, O; Coulibaly, S; Banou, A
2002-02-01
Prior to commencing a campaign to eliminate blinding trachoma in Mali, a national disease prevalence survey was conducted from March 1996 to June 1997. The prevalence of trachoma was estimated and potential risk factors were studied. In each of Mali's seven regions (excluding the capital Bamako), a sample of 30 clusters was taken from the general population, in accordance with the principle of probability proportional to the size of the community. All children under 10 years of age were examined. The simplified clinical coding system proposed by the World Health Organization was used. The position of each village was established and subsequently related to the nearest meteorological station. Socioeconomic and environmental information was collected at both village and household level. The mother or caretaker of each child was questioned about availability and use of water for washing the child. At the time of examination, facial cleanliness and the presence of flies on the face were noted. A total of 15,187 children under 10 years of age were examined. The prevalence of active trachoma (follicular [TF] or intense trachoma [TI]) was 34.9% (95% CI : 32.3-37.6) and the prevalence of TI was 4.2% (95% CI : 3.5-5.0). Aridity/environmental dryness appears to be a risk factor influencing the current geographical distribution of trachoma. Small villages had considerably higher trachoma prevalence than their larger neighbours. The proximity of a medical centre and the existence of social organizations such as a women's association were associated with lower levels of trachoma. Crowded living conditions increased the risk. Using a monetary marker of wealth, we observed a linear inverse relation between wealth and trachoma prevalence. The presence of a dirty face was strongly associated with trachoma (odds ratio [OR] = 3.67) as was the presence of flies on the child's face (OR = 3.62). Trachoma prevalence increased with distance to a water source. Disease prevalence decreased with a higher frequency of both face washing and bathing. Of all the risk factors examined, facial cleanliness had the strongest association with the prevalence of trachoma. This was followed by the presence of flies on the child's face. Both face washing and bathing showed beneficial effects. Socioeconomic factors such as wealth were significantly explanatory. It is likely that hygiene education and fly control by environmental improvement could have a very significant impact on the prevalence of trachoma in Mali.
Localization of synchronous cortical neural sources.
Zerouali, Younes; Herry, Christophe L; Jemel, Boutheina; Lina, Jean-Marc
2013-03-01
Neural synchronization is a key mechanism to a wide variety of brain functions, such as cognition, perception, or memory. High temporal resolution achieved by EEG recordings allows the study of the dynamical properties of synchronous patterns of activity at a very fine temporal scale but with very low spatial resolution. Spatial resolution can be improved by retrieving the neural sources of EEG signal, thus solving the so-called inverse problem. Although many methods have been proposed to solve the inverse problem and localize brain activity, few of them target the synchronous brain regions. In this paper, we propose a novel algorithm aimed at localizing specifically synchronous brain regions and reconstructing the time course of their activity. Using multivariate wavelet ridge analysis, we extract signals capturing the synchronous events buried in the EEG and then solve the inverse problem on these signals. Using simulated data, we compare results of source reconstruction accuracy achieved by our method to a standard source reconstruction approach. We show that the proposed method performs better across a wide range of noise levels and source configurations. In addition, we applied our method on real dataset and identified successfully cortical areas involved in the functional network underlying visual face perception. We conclude that the proposed approach allows an accurate localization of synchronous brain regions and a robust estimation of their activity.
Dahl, Asa; Nyberg, Helene; Edéll-Gustafsson, Ulla
2003-10-01
Our knowledge of unstable critically ill patients placed in an inverse bed position on the neurointensive care unit (NICU) is fairly limited. The purpose of this study was to ascertain the variation in nurses' conceptions of the impact of clinical experiences on the care and working environments among patients with the head towards the centre of the room on an NICU. An important research question was: how is the nursing care of patients facing inwards on an NICU perceived? Interviews were conducted and analysed with 15 nurses, using the method of phenomenography. From a nursing perspective, four descriptive categories were found, which partly distinguished the nursing psychosocial environment from the physical environment. These were safety and security of mobile computer tomography (CT) on the NICU, availability and overview, integrated holistic view in an open nursing psychosocial environment and adaptation of practical equipment. In conclusion, inverse bed position is important for more individualised neurointensive nursing care among unstable patients subjected to frequent CT scans on the unit. More stable patients should be turned back to the traditional bed position in order to promote their recovery process. This new knowledge is important for the development of quality assurance, with regard to, amongst other things, the patient's dignity.
Shear response of Σ3{112} twin boundaries in face-centered-cubic metals
NASA Astrophysics Data System (ADS)
Wang, J.; Misra, A.; Hirth, J. P.
2011-02-01
Molecular statics and dynamics simulations were used to study the mechanisms of sliding and migration of Σ3{112} incoherent twin boundaries (ITBs) under applied shear acting in the boundary in the face-centered-cubic (fcc) metals, Ag, Cu, Pd, and Al, of varying stacking fault energies. These studies revealed that (i) ITBs can dissociate into two phase boundaries (PBs), bounding the hexagonal 9R phase, that contain different arrays of partial dislocations; (ii) the separation distance between the two PBs scales inversely with increasing stacking fault energy; (iii) for fcc metals with low stacking fault energy, one of the two PBs migrates through the collective glide of partials, referred to as the phase-boundary-migration (PBM) mechanism; (iv) for metals with high stacking energy, ITBs experience a coupled motion (migration and sliding) through the glide of interface disconnections, referred to as the interface-disconnection-glide (IDG) mechanism.
Li, YuHui; Jin, FeiTeng
2017-01-01
The inversion design approach is a very useful tool for the complex multiple-input-multiple-output nonlinear systems to implement the decoupling control goal, such as the airplane model and spacecraft model. In this work, the flight control law is proposed using the neural-based inversion design method associated with the nonlinear compensation for a general longitudinal model of the airplane. First, the nonlinear mathematic model is converted to the equivalent linear model based on the feedback linearization theory. Then, the flight control law integrated with this inversion model is developed to stabilize the nonlinear system and relieve the coupling effect. Afterwards, the inversion control combined with the neural network and nonlinear portion is presented to improve the transient performance and attenuate the uncertain effects on both external disturbances and model errors. Finally, the simulation results demonstrate the effectiveness of this controller. PMID:29410680
Stochastic Gabor reflectivity and acoustic impedance inversion
NASA Astrophysics Data System (ADS)
Hariri Naghadeh, Diako; Morley, Christopher Keith; Ferguson, Angus John
2018-02-01
To delineate subsurface lithology to estimate petrophysical properties of a reservoir, it is possible to use acoustic impedance (AI) which is the result of seismic inversion. To change amplitude to AI, removal of wavelet effects from the seismic signal in order to get a reflection series, and subsequently transforming those reflections to AI, is vital. To carry out seismic inversion correctly it is important to not assume that the seismic signal is stationary. However, all stationary deconvolution methods are designed following that assumption. To increase temporal resolution and interpretation ability, amplitude compensation and phase correction are inevitable. Those are pitfalls of stationary reflectivity inversion. Although stationary reflectivity inversion methods are trying to estimate reflectivity series, because of incorrect assumptions their estimations will not be correct, but may be useful. Trying to convert those reflection series to AI, also merging with the low frequency initial model, can help us. The aim of this study was to apply non-stationary deconvolution to eliminate time variant wavelet effects from the signal and to convert the estimated reflection series to the absolute AI by getting bias from well logs. To carry out this aim, stochastic Gabor inversion in the time domain was used. The Gabor transform derived the signal’s time-frequency analysis and estimated wavelet properties from different windows. Dealing with different time windows gave an ability to create a time-variant kernel matrix, which was used to remove matrix effects from seismic data. The result was a reflection series that does not follow the stationary assumption. The subsequent step was to convert those reflections to AI using well information. Synthetic and real data sets were used to show the ability of the introduced method. The results highlight that the time cost to get seismic inversion is negligible related to general Gabor inversion in the frequency domain. Also, obtaining bias could help the method to estimate reliable AI. To justify the effect of random noise on deterministic and stochastic inversion results, a stationary noisy trace with signal-to-noise ratio equal to 2 was used. The results highlight the inability of deterministic inversion in dealing with a noisy data set even using a high number of regularization parameters. Also, despite the low level of signal, stochastic Gabor inversion not only can estimate correctly the wavelet’s properties but also, because of bias from well logs, the inversion result is very close to the real AI. Comparing deterministic and introduced inversion results on a real data set shows that low resolution results, especially in the deeper parts of seismic sections using deterministic inversion, creates significant reliability problems for seismic prospects, but this pitfall is solved completely using stochastic Gabor inversion. The estimated AI using Gabor inversion in the time domain is much better and faster than general Gabor inversion in the frequency domain. This is due to the extra number of windows required to analyze the time-frequency information and also the amount of temporal increment between windows. In contrast, stochastic Gabor inversion can estimate trustable physical properties close to the real characteristics. Applying to a real data set could give an ability to detect the direction of volcanic intrusion and the ability of lithology distribution delineation along the fan. Comparing the inversion results highlights the efficiency of stochastic Gabor inversion to delineate lateral lithology changes because of the improved frequency content and zero phasing of the final inversion volume.
NASA Astrophysics Data System (ADS)
Brezinsek, S.; Laengner, M.; Coenen, J. W.; O'Mullane, M. G.; Pospieszczyk, A.; Sergienko, G.; Samm, U.
2017-12-01
Optical emission spectroscopy can be applied to determine in situ tungsten particle fluxes from erosion processes at plasma-facing materials. Inverse photon efficiencies convert photon fluxes of WI and WII line transitions into W and {{{W}}}+ particle fluxes, respectively, dependening on the local plasma conditions. Experiments in TEXTOR were carried out to determine effective conversion factors for different WI and WII transitions with the aid of WF6 injection into deuterium scrape-off layer plasmas in the electron temperature T e range between {T}{e}=20 {eV} and {T}{e}=82 {eV}. The inverse photon efficiencies or so-called effective \\tfrac{S}{{XB}}-values have been determined for WI lines at λ =400.9 {nm}, 429.5 nm, 488.7 nm, 498.3 nm, and 522.5 nm as well as for WII at λ =434.6 {nm} and compared with theoretical calculations from the ADAS data base. Moreover, a multi-machine scaling for the \\tfrac{S}{{XB}}-value in the range of T e between 2...100 {eV} has been determined for the most prominent WI line at λ =400.9 {nm} to \\tfrac{S}{{XB}}({T}{e})=53.63-56.07× {e}(0.045× {T{e}[{eV}])} considering experimental data from TEXTOR, ASDEX Upgrade, PSI and PISCES. Comparison with ADAS calculations for the same transition reveal a good qualitative agreement with the dependence on T e , but an underestimation of ADAS calculations of less than 25% over the full covered range of experimentally accessible T e in the multi-machine scaling. A good agreement within the experimental uncertainties is found between TEXTOR and ADAS \\tfrac{S}{{XB}}-values for WI at λ =429.5 {nm} and λ =488.7 {nm} whereas an underestimation of up to a factor two of ADAS values for WI at λ =522.5 {nm} and λ =498.3 {nm} was measured. Potentially, reasons for the discrepancy are an overestimation of applied ionisation rate coefficients in ADAS for neutral W and a stronger electron dependence n e for these transitions.
Inversion technique for IR heterodyne sounding of stratospheric constituents from space platforms
NASA Technical Reports Server (NTRS)
Abbas, M. M.; Shapiro, G. L.; Alvarez, J. M.
1981-01-01
The techniques which have been employed for inversion of IR heterodyne measurements for remote sounding of stratospheric trace constituents usually rely on either geometric effects based on limb-scan observations (i.e., onion peel techniques) or spectral effects by using weighting functions corresponding to different frequencies of an IR spectral line. An experimental approach and inversion technique are discussed which optimize the retrieval of concentration profiles by combining the geometric and the spectral effects in an IR heterodyne receiver. The results of inversions of some synthetic CIO spectral lines corresponding to solar occultation limb scans of the stratosphere are presented, indicating considerable improvement in the accuracy of the retrieved profiles. The effects of noise on the accuracy of retrievals are discussed for realistic situations.
Inversion technique for IR heterodyne sounding of stratospheric constituents from space platforms.
Abbas, M M; Shapiro, G L; Alvarez, J M
1981-11-01
The techniques which have been employed for inversion of IR heterodyne measurements for remote sounding of stratospheric trace constituents usually rely on either geometric effects based on limb-scan observations (i.e., onion peel techniques) or spectral effects by using weighting functions corresponding to different frequencies of an IR spectral line. An experimental approach and inversion technique are discussed which optimize the retrieval of concentration profiles by combining the geometric and the spectral effects in an IR heterodyne receiver. The results of inversions of some synthetic ClO spectral lines corresponding to solar occultation limb scans of the stratosphere are presented, indicating considerable improvement in the accuracy of the retrieved profiles. The effects of noise on the accuracy of retrievals are discussed for realistic situations.
Normal composite face effects in developmental prosopagnosia.
Biotti, Federica; Wu, Esther; Yang, Hua; Jiahui, Guo; Duchaine, Bradley; Cook, Richard
2017-10-01
Upright face perception is thought to involve holistic processing, whereby local features are integrated into a unified whole. Consistent with this view, the top half of one face appears to fuse perceptually with the bottom half of another, when aligned spatially and presented upright. This 'composite face effect' reveals a tendency to integrate information from disparate regions when faces are presented canonically. In recent years, the relationship between susceptibility to the composite effect and face recognition ability has received extensive attention both in participants with normal face recognition and participants with developmental prosopagnosia. Previous results suggest that individuals with developmental prosopagnosia may show reduced susceptibility to the effect suggestive of diminished holistic face processing. Here we describe two studies that examine whether developmental prosopagnosia is associated with reduced composite face effects. Despite using independent samples of developmental prosopagnosics and different composite procedures, we find no evidence for reduced composite face effects. The experiments yielded similar results; highly significant composite effects in both prosopagnosic groups that were similar in magnitude to the effects found in participants with normal face processing. The composite face effects exhibited by both samples and the controls were greatly diminished when stimulus arrangements were inverted. Our finding that the whole-face binding process indexed by the composite effect is intact in developmental prosopagnosia indicates that other factors are responsible for developmental prosopagnosia. These results are also inconsistent with suggestions that susceptibility to the composite face effect and face recognition ability are tightly linked. While the holistic process revealed by the composite face effect may be necessary for typical face perception, it is not sufficient; individual differences in face recognition ability likely reflect variability in multiple sequential processes. Copyright © 2017 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elyasi, Mehrdad; Bhatia, Charanjit S.; Yang, Hyunsoo, E-mail: eleyang@nus.edu.sg
2015-02-14
We have proposed a method to synchronize multiple spin-transfer torque oscillators based on spin pumping, inverse spin Hall, and spin Hall effects. The proposed oscillator system consists of a series of nano-magnets in junction with a normal metal with high spin-orbit coupling, and an accumulative feedback loop. We conduct simulations to demonstrate the effect of modulated charge currents in the normal metal due to spin pumping from each nano-magnet. We show that the interplay between the spin Hall effect and inverse spin Hall effect results in synchronization of the nano-magnets.
NASA Astrophysics Data System (ADS)
Hamdi, H.; Qausar, A. M.; Srigutomo, W.
2016-08-01
Controlled source audio-frequency magnetotellurics (CSAMT) is a frequency-domain electromagnetic sounding technique which uses a fixed grounded dipole as an artificial signal source. Measurement of CSAMT with finite distance between transmitter and receiver caused a complex wave. The shifted of the electric field due to the static effect caused elevated resistivity curve up or down and affects the result of measurement. The objective of this study was to obtain data that have been corrected for source and static effects as to have the same characteristic as MT data which are assumed to exhibit plane wave properties. Corrected CSAMT data were inverted to reveal subsurface resistivity model. Source effect correction method was applied to eliminate the effect of the signal source and static effect was corrected by using spatial filtering technique. Inversion method that used in this study is the Occam's 2D Inversion. The results of inversion produces smooth models with a small misfit value, it means the model can describe subsurface conditions well. Based on the result of inversion was predicted measurement area is rock that has high permeability values with rich hot fluid.
Optimal Design for Parameter Estimation in EEG Problems in a 3D Multilayered Domain
2014-03-30
dipole, C(x) = q δ(x − rq), where δ is the Dirac distribution, rq is a fixed point in the brain which represents the dipole location, and q is the dipole...again based on the formulations discussed above, we consider a function F of the form F (x, θ) = qδ(x− rq), where δ denotes the dirac distribution...Inverse Problems, 12, (1996), 565–577. [5] H.T. Banks, M.W. Buksas and T. Lin, Electromagnetic Material Interrogation Using Conductive Inter- faces and
Quintana, D S; Westlye, L T; Rustan, Ø G; Tesli, N; Poppy, C L; Smevik, H; Tesli, M; Røine, M; Mahmoud, R A; Smerud, K T; Djupesland, P G; Andreassen, O A
2015-01-01
Despite the promise of intranasal oxytocin (OT) for modulating social behavior, recent work has provided mixed results. This may relate to suboptimal drug deposition achieved with conventional nasal sprays, inter-individual differences in nasal physiology and a poor understanding of how intranasal OT is delivered to the brain in humans. Delivering OT using a novel ‘Breath Powered' nasal device previously shown to enhance deposition in intranasal sites targeted for nose-to-brain transport, we evaluated dose-dependent effects on social cognition, compared response with intravenous (IV) administration of OT, and assessed nasal cavity dimensions using acoustic rhinometry. We adopted a randomized, double-blind, double-dummy, crossover design, with 16 healthy male adults completing four single-dose treatments (intranasal 8 IU (international units) or 24 IU OT, 1 IU OT IV and placebo). The primary outcome was social cognition measured by emotional ratings of facial images. Secondary outcomes included the pharmacokinetics of OT, vasopressin and cortisol in blood and the association between nasal cavity dimensions and emotional ratings. Despite the fact that all the treatments produced similar plasma OT increases compared with placebo, there was a main effect of treatment on anger ratings of emotionally ambiguous faces. Pairwise comparisons revealed decreased ratings after 8 IU OT in comparison to both placebo and 24 IU OT. In addition, there was an inverse relationship between nasal valve dimensions and anger ratings of ambiguous faces after 8-IU OT treatment. These findings provide support for a direct nose-to-brain effect, independent of blood absorption, of low-dose OT delivered from a Breath Powered device. PMID:26171983
Quintana, D S; Westlye, L T; Rustan, Ø G; Tesli, N; Poppy, C L; Smevik, H; Tesli, M; Røine, M; Mahmoud, R A; Smerud, K T; Djupesland, P G; Andreassen, O A
2015-07-14
Despite the promise of intranasal oxytocin (OT) for modulating social behavior, recent work has provided mixed results. This may relate to suboptimal drug deposition achieved with conventional nasal sprays, inter-individual differences in nasal physiology and a poor understanding of how intranasal OT is delivered to the brain in humans. Delivering OT using a novel 'Breath Powered' nasal device previously shown to enhance deposition in intranasal sites targeted for nose-to-brain transport, we evaluated dose-dependent effects on social cognition, compared response with intravenous (IV) administration of OT, and assessed nasal cavity dimensions using acoustic rhinometry. We adopted a randomized, double-blind, double-dummy, crossover design, with 16 healthy male adults completing four single-dose treatments (intranasal 8 IU (international units) or 24 IU OT, 1 IU OT IV and placebo). The primary outcome was social cognition measured by emotional ratings of facial images. Secondary outcomes included the pharmacokinetics of OT, vasopressin and cortisol in blood and the association between nasal cavity dimensions and emotional ratings. Despite the fact that all the treatments produced similar plasma OT increases compared with placebo, there was a main effect of treatment on anger ratings of emotionally ambiguous faces. Pairwise comparisons revealed decreased ratings after 8 IU OT in comparison to both placebo and 24 IU OT. In addition, there was an inverse relationship between nasal valve dimensions and anger ratings of ambiguous faces after 8-IU OT treatment. These findings provide support for a direct nose-to-brain effect, independent of blood absorption, of low-dose OT delivered from a Breath Powered device.
Spectral optimized asymmetric segmented phase-only correlation filter.
Leonard, I; Alfalou, A; Brosseau, C
2012-05-10
We suggest a new type of optimized composite filter, i.e., the asymmetric segmented phase-only filter (ASPOF), for improving the effectiveness of a VanderLugt correlator (VLC) when used for face identification. Basically, it consists in merging several reference images after application of a specific spectral optimization method. After segmentation of the spectral filter plane to several areas, each area is assigned to a single winner reference according to a new optimized criterion. The point of the paper is to show that this method offers a significant performance improvement on standard composite filters for face identification. We first briefly revisit composite filters [adapted, phase-only, inverse, compromise optimal, segmented, minimum average correlation energy, optimal trade-off maximum average correlation, and amplitude-modulated phase-only (AMPOF)], which are tools of choice for face recognition based on correlation techniques, and compare their performances with those of the ASPOF. We illustrate some of the drawbacks of current filters for several binary and grayscale image identifications. Next, we describe the optimization steps and introduce the ASPOF that can overcome these technical issues to improve the quality and the reliability of the correlation-based decision. We derive performance measures, i.e., PCE values and receiver operating characteristic curves, to confirm consistency of the results. We numerically find that this filter increases the recognition rate and decreases the false alarm rate. The results show that the discrimination of the ASPOF is comparable to that of the AMPOF, but the ASPOF is more robust than the trade-off maximum average correlation height against rotation and various types of noise sources. Our method has several features that make it amenable to experimental implementation using a VLC.
Lee, Myung W.
2006-01-01
Elastic properties of gas hydrate-bearing sediments (GHBS) are important for identifying and quantifying gas hydrate as well as discriminating the effects of free gas on velocity from that due to overpressure. Elastic properties of GHBS sediments can be estimated from elastic inversion using the elastic impedance. The accuracy of elastic inversion can be increased by using the predicted S-wave velocity (Vs) in the parameter k, which is k = (Vs / Vp)2. However, when Vs is less than about 0.6 kilometer per second, the inversion is inaccurate, partly because of the difficulty in accurately predicting low S-wave velocities and partly because of the large error associated with small k values. A new formula that leads to estimates of only the high-frequency part of velocity is proposed by decomposing Vs into low- and high-frequency parts. This new inversion formula is applied to a variety of well logs, and the results demonstrate its effectiveness for all ranges of Vs as long as the deviation of Vs from the low-frequency part of Vs is small. For GHBS, the deviation of Vs from the low-frequency part of Vs can be large for moderate to high gas hydrate saturations. Therefore, the new formula is not effective for elastic inversion for GHBS unless the gas hydrate effect is incorporated into the low-frequency part of Vs. For inversion of GHBS with Vs greater than about 0.6 kilometer per second, the original formulation is preferable.
From scores to face templates: a model-based approach.
Mohanty, Pranab; Sarkar, Sudeep; Kasturi, Rangachar
2007-12-01
Regeneration of templates from match scores has security and privacy implications related to any biometric authentication system. We propose a novel paradigm to reconstruct face templates from match scores using a linear approach. It proceeds by first modeling the behavior of the given face recognition algorithm by an affine transformation. The goal of the modeling is to approximate the distances computed by a face recognition algorithm between two faces by distances between points, representing these faces, in an affine space. Given this space, templates from an independent image set (break-in) are matched only once with the enrolled template of the targeted subject and match scores are recorded. These scores are then used to embed the targeted subject in the approximating affine (non-orthogonal) space. Given the coordinates of the targeted subject in the affine space, the original template of the targeted subject is reconstructed using the inverse of the affine transformation. We demonstrate our ideas using three, fundamentally different, face recognition algorithms: Principal Component Analysis (PCA) with Mahalanobis cosine distance measure, Bayesian intra-extrapersonal classifier (BIC), and a feature-based commercial algorithm. To demonstrate the independence of the break-in set with the gallery set, we select face templates from two different databases: Face Recognition Grand Challenge (FRGC) and Facial Recognition Technology (FERET) Database (FERET). With an operational point set at 1 percent False Acceptance Rate (FAR) and 99 percent True Acceptance Rate (TAR) for 1,196 enrollments (FERET gallery), we show that at most 600 attempts (score computations) are required to achieve a 73 percent chance of breaking in as a randomly chosen target subject for the commercial face recognition system. With similar operational set up, we achieve a 72 percent and 100 percent chance of breaking in for the Bayesian and PCA based face recognition systems, respectively. With three different levels of score quantization, we achieve 69 percent, 68 percent and 49 percent probability of break-in, indicating the robustness of our proposed scheme to score quantization. We also show that the proposed reconstruction scheme has 47 percent more probability of breaking in as a randomly chosen target subject for the commercial system as compared to a hill climbing approach with the same number of attempts. Given that the proposed template reconstruction method uses distinct face templates to reconstruct faces, this work exposes a more severe form of vulnerability than a hill climbing kind of attack where incrementally different versions of the same face are used. Also, the ability of the proposed approach to reconstruct actual face templates of the users increases privacy concerns in biometric systems.
Iyer, Bharat Ramasubramanian; Zadafiya, Punit; Vetal, Pallavi Vijay
2017-01-01
The free energy of water-to-interface amino acid partitioning is a major contributing factor in membrane protein folding and stability. The interface residues at the C terminus of transmembrane β-barrels form the β-signal motif required for assisted β-barrel assembly in vivo but are believed to be less important for β-barrel assembly in vitro. Here, we experimentally measured the thermodynamic contribution of all 20 amino acids at the β-signal motif to the unassisted folding of the model β-barrel protein PagP. We obtained the partitioning free energy for all 20 amino acids at the lipid-facing interface (ΔΔG0w,i(φ)) and the protein-facing interface (ΔΔG0w,i(π)) residues and found that hydrophobic amino acids are most favorably transferred to the lipid-facing interface, whereas charged and polar groups display the highest partitioning energy. Furthermore, the change in non-polar surface area correlated directly with the partitioning free energy for the lipid-facing residue and inversely with the protein-facing residue. We also demonstrate that the interface residues of the β-signal motif are vital for in vitro barrel assembly, because they exhibit a side chain–specific energetic contribution determined by the change in nonpolar accessible surface. We further establish that folding cooperativity and hydrophobic collapse are balanced at the membrane interface for optimal stability of the PagP β-barrel scaffold. We conclude that the PagP C-terminal β-signal motif influences the folding cooperativity and stability of the folded β-barrel and that the thermodynamic contributions of the lipid- and protein-facing residues in the transmembrane protein β-signal motif depend on the nature of the amino acid side chain. PMID:28592485
Assigning uncertainties in the inversion of NMR relaxation data.
Parker, Robert L; Song, Yi-Qaio
2005-06-01
Recovering the relaxation-time density function (or distribution) from NMR decay records requires inverting a Laplace transform based on noisy data, an ill-posed inverse problem. An important objective in the face of the consequent ambiguity in the solutions is to establish what reliable information is contained in the measurements. To this end we describe how upper and lower bounds on linear functionals of the density function, and ratios of linear functionals, can be calculated using optimization theory. Those bounded quantities cover most of those commonly used in the geophysical NMR, such as porosity, T(2) log-mean, and bound fluid volume fraction, and include averages over any finite interval of the density function itself. In the theory presented statistical considerations enter to account for the presence of significant noise in the signal, but not in a prior characterization of density models. Our characterization of the uncertainties is conservative and informative; it will have wide application in geophysical NMR and elsewhere.
Doi, Hirokazu; Fujisawa, Takashi X; Kanai, Chieko; Ohta, Haruhisa; Yokoi, Hideki; Iwanami, Akira; Kato, Nobumasa; Shinohara, Kazuyuki
2013-09-01
This study investigated the ability of adults with Asperger syndrome to recognize emotional categories of facial expressions and emotional prosodies with graded emotional intensities. The individuals with Asperger syndrome showed poorer recognition performance for angry and sad expressions from both facial and vocal information. The group difference in facial expression recognition was prominent for stimuli with low or intermediate emotional intensities. In contrast to this, the individuals with Asperger syndrome exhibited lower recognition accuracy than typically-developed controls mainly for emotional prosody with high emotional intensity. In facial expression recognition, Asperger and control groups showed an inversion effect for all categories. The magnitude of this effect was less in the Asperger group for angry and sad expressions, presumably attributable to reduced recruitment of the configural mode of face processing. The individuals with Asperger syndrome outperformed the control participants in recognizing inverted sad expressions, indicating enhanced processing of local facial information representing sad emotion. These results suggest that the adults with Asperger syndrome rely on modality-specific strategies in emotion recognition from facial expression and prosodic information.
Pabari, Ritesh M; Ramtoola, Zebunnissa
2012-07-01
A two factor, three level (3(2)) face centred, central composite design (CCD) was applied to investigate the main and interaction effects of tablet diameter and compression force (CF) on hardness, disintegration time (DT) and porosity of mannitol based orodispersible tablets (ODTs). Tablet diameters of 10, 13 and 15 mm, and CF of 10, 15 and 20 kN were studied. Results of multiple linear regression analysis show that both the tablet diameter and CF influence tablet characteristics. A negative value of regression coefficient for tablet diameter showed an inverse relationship with hardness and DT. A positive value of regression coefficient for CF indicated an increase in hardness and DT with increasing CF as a result of the decrease in tablet porosity. Interestingly, at the larger tablet diameter of 15 mm, while hardness increased and porosity decreased with an increase in CF, the DT was resistant to change. The optimised combination was a tablet of 15 mm diameter compressed at 15 kN showing a rapid DT of 37.7s and high hardness of 71.4N. Using these parameters, ODTs containing ibuprofen showed no significant change in DT (ANOVA; p>0.05) irrespective of the hydrophobicity of the ibuprofen. Copyright © 2012 Elsevier B.V. All rights reserved.
Association of socioeconomic status and cognitive functioning change among elderly Chinese people.
Yang, Lei; Martikainen, Pekka; Silventoinen, Karri; Konttinen, Hanna
2016-09-01
the inverse association between high socioeconomic status and impaired cognitive functioning in old age has been widely studied. However, it is still inconclusive whether higher socioeconomic status slows the rate of cognitive decline over ageing, especially in non-Western populations. We examined this association using a large population-based longitudinal survey of older Chinese persons. the sample came from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) (from the years 2002 to 2011, N = 15,798 at baseline, aged 65-105). The Mini-Mental State Examination (MMSE) based on face-to-face interviews was used to assess cognitive functioning. Socioeconomic status was assessed using educational attainment and household income per capita. Latent growth curve and selection model considering the attrition during the follow-up were utilised to assess the effect of socioeconomic status on the rate of change in cognitive functioning. at baseline, younger elderly people, urban residents and elderly people living alone had better cognitive performance in both genders. Educational attainment was positively associated with cognitive functioning at baseline but did not have a significant effect on the rate of change in cognitive functioning. Higher incomes were associated with better cognitive functioning at baseline, but this difference diminished during the follow-up. higher socioeconomic status was associated with better cognitive performance at baseline but could not protect against the rate of decline in cognitive functioning measured by MMSE in this longitudinal study for elderly Chinese people. © The Author 2016. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Large Airborne Full Tensor Gradient Data Inversion Based on a Non-Monotone Gradient Method
NASA Astrophysics Data System (ADS)
Sun, Yong; Meng, Zhaohai; Li, Fengting
2018-03-01
Following the development of gravity gradiometer instrument technology, the full tensor gravity (FTG) data can be acquired on airborne and marine platforms. Large-scale geophysical data can be obtained using these methods, making such data sets a number of the "big data" category. Therefore, a fast and effective inversion method is developed to solve the large-scale FTG data inversion problem. Many algorithms are available to accelerate the FTG data inversion, such as conjugate gradient method. However, the conventional conjugate gradient method takes a long time to complete data processing. Thus, a fast and effective iterative algorithm is necessary to improve the utilization of FTG data. Generally, inversion processing is formulated by incorporating regularizing constraints, followed by the introduction of a non-monotone gradient-descent method to accelerate the convergence rate of FTG data inversion. Compared with the conventional gradient method, the steepest descent gradient algorithm, and the conjugate gradient algorithm, there are clear advantages of the non-monotone iterative gradient-descent algorithm. Simulated and field FTG data were applied to show the application value of this new fast inversion method.
Lin, Tian; Lendry, Reesa; Ebner, Natalie C
2016-11-01
Evidence of effects of face attractiveness on memory is mixed and little is known about the underlying mechanisms of this relationship. Previous work suggests a possible mediating role of affective responding to faces (i.e., face likeability) on the relationship between face attractiveness and memory. Age-related change in social motivation may reduce the relevance of face attractiveness in older adults, with downstream effects on memory. In the present study, 50 young and 51 older participants were presented with face-trait pairs. Faces varied in attractiveness. Participants then completed a face-trait associative recognition memory task and provided likeability ratings for each face. There was a memory-enhancing effect of face attractiveness in young (but not older) participants, which was partially mediated by face likeability. In addition, more attractive and less attractive (compared to moderately attractive) faces were more likely remembered by both young and older participants. This quadratic effect of face attractiveness on memory was not mediated by face likeability. Findings are discussed in the context of motivational influences on memory that vary with age.
The Genetic Content of Chromosomal Inversions across a Wide Latitudinal Gradient
Simões, Pedro; Calabria, Gemma; Picão-Osório, João; Balanyà, Joan; Pascual, Marta
2012-01-01
There is increasing evidence regarding the role of chromosomal inversions in relevant biological processes such as local adaptation and speciation. A classic example of the adaptive role of chromosomal polymorphisms is given by the clines of inversion frequencies in Drosophila subobscura, repeatable across continents. Nevertheless, not much is known about the molecular variation associated with these polymorphisms. We characterized the genetic content of ca. 600 individuals from nine European populations following a latitudinal gradient by analysing 19 microsatellite loci from two autosomes (J and U) and the sex chromosome (A), taking into account their chromosomal inversions. Our results clearly demonstrate the molecular genetic uniformity within a given chromosomal inversion across a large latitudinal gradient, particularly from Groningen (Netherlands) in the north to Málaga (Spain) in the south, experiencing highly diverse environmental conditions. This low genetic differentiation within the same gene arrangement across the nine European populations is consistent with the local adaptation hypothesis for th evolutionof chromosomal polymorphisms. We also show the effective role of chromosomal inversions in maintaining different genetic pools within these inverted genomic regions even in the presence of high gene flow. Inversions represent thus an important barrier to gene flux and can help maintain specific allelic combinations with positive effects on fitness. Consistent patterns of microsatellite allele-inversion linkage disequilibrium particularly in loci within inversions were also observed. Finally, we identified areas within inversions presenting clinal variation that might be under selection. PMID:23272126
NASA Astrophysics Data System (ADS)
Elling, R. P.; Stein, C. A.; Stein, S.; Kley, J.; Keller, G. R.; Wysession, M. E.
2017-12-01
Continental rifts evolve to seafloor spreading and are preserved in passive margins, or fail and remain as fossil features in continents. Rifts at different stages give insight into these evolutionary paths. Of particular interest is the evolution of volcanic passive margins, which are characterized by seaward dipping reflectors, volcanic rocks yielding magnetic anomalies landward of the oldest spreading anomalies, and are underlain by high-velocity lower crustal bodies. How and when these features form remains unclear. Insights are given by the Midcontinent Rift (MCR), which began to form during the 1.1 Ga rifting of Amazonia from Laurentia, but failed when seafloor spreading was established elsewhere. MCR volcanics are much thicker than other continental flood basalts, due to deposition in a narrow rift rather than a broad region, giving a rift's geometry but a LIP's magma volume. The MCR provides a snapshot of the deposition of a thick and highly magnetized volcanic section during rifting. Surface exposures and reflection seismic data near Lake Superior show a rift basin filled by inward-dipping flood basalt layers. Had the rift evolved to seafloor spreading, the basin would have split into two sets of volcanics with opposite-facing SDRs, each with a magnetic anomaly. Because the rift formed as a series of alternating half-grabens, structural asymmetries between conjugate margins would have naturally occurred had it gone to completion. Hence the MCR implies that many passive margin features form prior to seafloor spreading. Massive inversion of the MCR long after it failed has provided a much clearer picture of its structure compared to failed rifts with lesser degrees of inversion. Seismic imaging as well as gravity and magnetic modeling provide important insight into the effects of inversion on failed rifts. The MCR provides an end member for the evolution of actively extending rifts, characterized by upwelling mantle and negative gravity anomalies, to failed and inverted rifts without upwelling mantle and positive gravity anomalies.
Are Face and Object Recognition Independent? A Neurocomputational Modeling Exploration.
Wang, Panqu; Gauthier, Isabel; Cottrell, Garrison
2016-04-01
Are face and object recognition abilities independent? Although it is commonly believed that they are, Gauthier et al. [Gauthier, I., McGugin, R. W., Richler, J. J., Herzmann, G., Speegle, M., & VanGulick, A. E. Experience moderates overlap between object and face recognition, suggesting a common ability. Journal of Vision, 14, 7, 2014] recently showed that these abilities become more correlated as experience with nonface categories increases. They argued that there is a single underlying visual ability, v, that is expressed in performance with both face and nonface categories as experience grows. Using the Cambridge Face Memory Test and the Vanderbilt Expertise Test, they showed that the shared variance between Cambridge Face Memory Test and Vanderbilt Expertise Test performance increases monotonically as experience increases. Here, we address why a shared resource across different visual domains does not lead to competition and to an inverse correlation in abilities? We explain this conundrum using our neurocomputational model of face and object processing ["The Model", TM, Cottrell, G. W., & Hsiao, J. H. Neurocomputational models of face processing. In A. J. Calder, G. Rhodes, M. Johnson, & J. Haxby (Eds.), The Oxford handbook of face perception. Oxford, UK: Oxford University Press, 2011]. We model the domain general ability v as the available computational resources (number of hidden units) in the mapping from input to label and experience as the frequency of individual exemplars in an object category appearing during network training. Our results show that, as in the behavioral data, the correlation between subordinate level face and object recognition accuracy increases as experience grows. We suggest that different domains do not compete for resources because the relevant features are shared between faces and objects. The essential power of experience is to generate a "spreading transform" for faces (separating them in representational space) that generalizes to objects that must be individuated. Interestingly, when the task of the network is basic level categorization, no increase in the correlation between domains is observed. Hence, our model predicts that it is the type of experience that matters and that the source of the correlation is in the fusiform face area, rather than in cortical areas that subserve basic level categorization. This result is consistent with our previous modeling elucidating why the FFA is recruited for novel domains of expertise [Tong, M. H., Joyce, C. A., & Cottrell, G. W. Why is the fusiform face area recruited for novel categories of expertise? A neurocomputational investigation. Brain Research, 1202, 14-24, 2008].
NASA Astrophysics Data System (ADS)
Allaerts, Dries; Meyers, Johan
2014-05-01
Atmospheric boundary layers (ABL) are frequently capped by an inversion layer limiting the entrainment rate and boundary layer growth. Commonly used analytical models state that the entrainment rate is inversely proportional to the inversion strength. The height of the inversion turns out to be a second important parameter. Conventionally neutral atmospheric boundary layers (CNBL) are ABLs with zero surface heat flux developing against a stratified free atmosphere. In this regime the inversion-filling process is merely driven by the downward heat flux at the inversion base. As a result, CNBLs are strongly dependent on the heating history of the boundary layer and strong inversions will fail to erode during the course of the day. In case of large wind farms, the power output of the farm inside a CNBL will depend on the height and strength of the inversion above the boundary layer. On the other hand, increased turbulence levels induced by wind farms may partially undermine the rigid lid effect of the capping inversion, enhance vertical entrainment of air into the farm, and increase boundary layer growth. A suite of large eddy simulations (LES) is performed to investigate the effect of the capping inversion on the conventionally neutral atmospheric boundary layer and on the wind farm performance under varying initial conditions. For these simulations our in-house pseudo-spectral LES code SP-Wind is used. The wind turbines are modelled using a non-rotating actuator disk method. In the absence of wind farms, we find that a decrease in inversion strength corresponds to a decrease in the geostrophic angle and an increase in entrainment rate and geostrophic drag. Placing the initial inversion base at higher altitudes further reduces the effect of the capping inversion on the boundary layer. The inversion can be fully neglected once it is situated above the equilibrium height that a truly neutral boundary layer would attain under the same external conditions such as geostrophic wind speed and surface roughness. Wind farm simulations show the expected increase in boundary layer height and growth rate with respect to the case without wind farms. Raising the initial strength of the capping inversion in these simulations dampens the turbulent growth of the boundary layer above the farm, decreasing the farms energy extraction. The authors acknowledge support from the European Research Council (FP7-Ideas, grant no. 306471). Simulations were performed on the computing infrastructure of the VSC Flemish Supercomputer Center, funded by the Hercules Foundation and the Flemish Government.
Three-dimensional Gravity Inversion with a New Gradient Scheme on Unstructured Grids
NASA Astrophysics Data System (ADS)
Sun, S.; Yin, C.; Gao, X.; Liu, Y.; Zhang, B.
2017-12-01
Stabilized gradient-based methods have been proved to be efficient for inverse problems. Based on these methods, setting gradient close to zero can effectively minimize the objective function. Thus the gradient of objective function determines the inversion results. By analyzing the cause of poor resolution on depth in gradient-based gravity inversion methods, we find that imposing depth weighting functional in conventional gradient can improve the depth resolution to some extent. However, the improvement is affected by the regularization parameter and the effect of the regularization term becomes smaller with increasing depth (shown as Figure 1 (a)). In this paper, we propose a new gradient scheme for gravity inversion by introducing a weighted model vector. The new gradient can improve the depth resolution more efficiently, which is independent of the regularization parameter, and the effect of regularization term will not be weakened when depth increases. Besides, fuzzy c-means clustering method and smooth operator are both used as regularization terms to yield an internal consecutive inverse model with sharp boundaries (Sun and Li, 2015). We have tested our new gradient scheme with unstructured grids on synthetic data to illustrate the effectiveness of the algorithm. Gravity forward modeling with unstructured grids is based on the algorithm proposed by Okbe (1979). We use a linear conjugate gradient inversion scheme to solve the inversion problem. The numerical experiments show a great improvement in depth resolution compared with regular gradient scheme, and the inverse model is compact at all depths (shown as Figure 1 (b)). AcknowledgeThis research is supported by Key Program of National Natural Science Foundation of China (41530320), China Natural Science Foundation for Young Scientists (41404093), and Key National Research Project of China (2016YFC0303100, 2017YFC0601900). ReferencesSun J, Li Y. 2015. Multidomain petrophysically constrained inversion and geology differentiation using guided fuzzy c-means clustering. Geophysics, 80(4): ID1-ID18. Okabe M. 1979. Analytical expressions for gravity anomalies due to homogeneous polyhedral bodies and translations into magnetic anomalies. Geophysics, 44(4), 730-741.
NASA Astrophysics Data System (ADS)
An, M.; Assumpcao, M.
2003-12-01
The joint inversion of receiver function and surface wave is an effective way to diminish the influences of the strong tradeoff among parameters and the different sensitivity to the model parameters in their respective inversions, but the inversion problem becomes more complex. Multi-objective problems can be much more complicated than single-objective inversion in the model selection and optimization. If objectives are involved and conflicting, models can be ordered only partially. In this case, Pareto-optimal preference should be used to select solutions. On the other hand, the inversion to get only a few optimal solutions can not deal properly with the strong tradeoff between parameters, the uncertainties in the observation, the geophysical complexities and even the incompetency of the inversion technique. The effective way is to retrieve the geophysical information statistically from many acceptable solutions, which requires more competent global algorithms. Competent genetic algorithms recently proposed are far superior to the conventional genetic algorithm and can solve hard problems quickly, reliably and accurately. In this work we used one of competent genetic algorithms, Bayesian Optimization Algorithm as the main inverse procedure. This algorithm uses Bayesian networks to draw out inherited information and can use Pareto-optimal preference in the inversion. With this algorithm, the lithospheric structure of Paran"› basin is inverted to fit both the observations of inter-station surface wave dispersion and receiver function.
Kuo, Chen-Chen; Li, Chi-Yen; Lee, Chi-Hung; Li, Hsiao-Chi; Li, Wen-Hsien
2015-08-25
We report on the design and observation of huge inverse magnetizations pointing in the direction opposite to the applied magnetic field, induced in nano-sized amorphous Ni shells deposited on crystalline Au nanoparticles by turning the applied magnetic field off. The magnitude of the induced inverse magnetization is very sensitive to the field reduction rate as well as to the thermal and field processes before turning the magnetic field off, and can be as high as 54% of the magnetization prior to cutting off the applied magnetic field. Memory effect of the induced inverse magnetization is clearly revealed in the relaxation measurements. The relaxation of the inverse magnetization can be described by an exponential decay profile, with a critical exponent that can be effectively tuned by the wait time right after reaching the designated temperature and before the applied magnetic field is turned off. The key to these effects is to have the induced eddy current running beneath the amorphous Ni shells through Faraday induction.
Rigola, Maria A; Baena, Neus; Català, Vicenç; Lozano, Iris; Gabau, Elisabet; Guitart, Miriam; Fuster, Carmen
2015-01-01
Most apparent balanced chromosomal inversions are usually clinically asymptomatic; however, infertility, miscarriages, and mental retardation have been reported in inversion carriers. We present a small family with a paracentric inversion 1q42.13q43 detected in routine prenatal diagnosis. Molecular cytogenetic methods defined the size of the inversion as 11.7 Mb and excluded other unbalanced chromosomal alterations in the patients. Our findings suggest that intellectual disability is caused by dysfunction, disruption, or position effects of genes located at or near the breakpoints involved in this inversion. © 2015 S. Karger AG, Basel.
Erasing the face after-effect.
Kiani, Ghazaleh; Davies-Thompson, Jodie; Barton, Jason J S
2014-10-24
Perceptual after-effects decay over time at a rate that depends on several factors, such as the duration of adaptation and the duration of the test stimuli. Whether this decay is accelerated by exposure to other faces after adaptation is not known. Our goal was to determine if the appearance of other faces during a delay period after adaptation affected the face identity after-effect. In the first experiment we investigated whether, in the perception of ambiguous stimuli created by morphing between two faces, the repulsive after-effects from adaptation to one face were reduced by brief presentation of the second face in a delay period. We found no effect; however, this may have been confounded by a small attractive after-effect from the interference face. In the second experiment, the interference stimuli were faces unrelated to those used as adaptation stimuli, and we examined after-effects at three different delay periods. This showed a decline in after-effects as the time since adaptation increased, and an enhancement of this decline by the presentation of intervening faces. An exponential model estimated that the intervening faces caused an 85% reduction in the time constant of the after-effect decay. In conclusion, we confirm that face after-effects decline rapidly after adaptation and that exposure to other faces hastens the re-setting of the system. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.
Wang, Zhe; Quinn, Paul C; Jin, Haiyang; Sun, Yu-Hao P; Tanaka, James W; Pascalis, Olivier; Lee, Kang
2018-04-25
Using a composite-face paradigm, we examined the holistic processing induced by Asian faces, Caucasian faces, and monkey faces with human Asian participants in two experiments. In Experiment 1, participants were asked to judge whether the upper halves of two faces successively presented were the same or different. A composite-face effect was found for Asian faces and Caucasian faces, but not for monkey faces. In Experiment 2, participants were asked to judge whether the lower halves of the two faces successively presented were the same or different. A composite-face effect was found for monkey faces as well as for Asian faces and Caucasian faces. Collectively, these results reveal that own-species (i.e., own-race and other-race) faces engage holistic processing in both upper and lower halves of the face, but other-species (i.e., monkey) faces engage holistic processing only when participants are asked to match the lower halves of the face. The findings are discussed in the context of a region-based holistic processing account for the species-specific effect in face recognition. Copyright © 2018 Elsevier Ltd. All rights reserved.
Wang, Jiao; Zhu, Yanna; Cai, Li; Jing, Jin; Chen, Yajun; Mai, Jincheng; Ma, Lu; Ma, Yinghua; Ma, Jun
2016-05-01
The present study aimed to investigate the prevalence of metabolic syndrome (MetS) in 7- to 17-year-old children and adolescents in China and to examine the relationship between MetS and its associated early-life factors. Data were collected using a standard parent/guardian questionnaire in a face-to-face interview. Each participant underwent a complete anthropometric evaluation. MetS was defined according to the criteria of the International Diabetes Federation (IDF; 2007) for children and adolescents. Guangzhou, a large city in South China, September 2013. A total of 1770 children and adolescents were enrolled in the study, including 913 girls (51·6%) and 857 boys (48·4%). The overall prevalence of MetS in children and adolescents was 1·1% (n 19), which was higher in boys (1·4%) than in girls (0·8%). Multivariate analysis indicated that high birth weight was significantly associated with abdominal obesity (OR=2·86; 95% CI 1·62, 5·06) and MetS (OR=3·61; 95% CI 1·33, 9·82). Furthermore, >6 months of maternal breast-feeding was inversely associated with MetS (OR=0·39; 95% CI 0·16, 0·98). Based on IDF criteria, the prevalence of MetS among southern Chinese children was significantly lower than that in other populations. High birth weight was significantly associated with abdominal obesity and MetS, and breast-feeding for longer than 6 months was inversely associated with MetS in South China.
Tapia, Antonio; Ruiz-de-Erenchun, Richard; Rengifo, Miguel
2006-08-01
One of the main objectives in facial lifting is to achieve an adequate facial contour, to enhance facial characteristics. Sometimes, facial areas are more or less accentuated, resulting in an unbalanced or inharmonious facial contour; this can be resolved in the context of a face lift. In the middle third of the face, two anatomical regions define the facial silhouette: the malar contour, with its bone support and superficial structures and, at the cheek level, intimately associated with the mastication system and the facial nerve, the buccal fat pad or Bichat fat pad. The authors describe their experience since 1998 using the double approach to malar atrophy and buccal fat pad hypertrophy in 194 patients with facial aging signs undergoing a face lift. All patients were offered a face lift with partial resection of the fat pad through facial incisions and a stronger malar projection using an inverse superficial musculoaponeurotic system flap. The main complications observed regarding this surgical technique, in order of appearance, were light asymmetry, caused by a persistent hematoma or swelling; paresthesia of the buccal and zygomatic branches, which resolved spontaneously; and a light sinking of the cheek caused by excessive resection. One patient underwent correction with a fat injection. The superior superficial musculoaponeurotic system flap and buccal fat pad resection provided excellent aesthetic results for a more harmonic and proportioned facial contour during rhytidectomy. Particularly in patients with round faces, the authors were able to obtain permanent malar symmetry and projection in addition to diminishing the cheek fullness.
Aberrant face and gaze habituation in fragile x syndrome.
Bruno, Jennifer Lynn; Garrett, Amy S; Quintin, Eve-Marie; Mazaika, Paul K; Reiss, Allan L
2014-10-01
The authors sought to investigate neural system habituation to face and eye gaze in fragile X syndrome, a disorder characterized by eye-gaze aversion, among other social and cognitive deficits. Participants (ages 15-25 years) were 30 individuals with fragile X syndrome (females, N=14) and a comparison group of 25 individuals without fragile X syndrome (females, N=12) matched for general cognitive ability and autism symptoms. Functional MRI (fMRI) was used to assess brain activation during a gaze habituation task. Participants viewed repeated presentations of four unique faces with either direct or averted eye gaze and judged the direction of eye gaze. Four participants (males, N=4/4; fragile X syndrome, N=3) were excluded because of excessive head motion during fMRI scanning. Behavioral performance did not differ between the groups. Less neural habituation (and significant sensitization) in the fragile X syndrome group was found in the cingulate gyrus, fusiform gyrus, and frontal cortex in response to all faces (direct and averted gaze). Left fusiform habituation in female participants was directly correlated with higher, more typical levels of the fragile X mental retardation protein and inversely correlated with autism symptoms. There was no evidence for differential habituation to direct gaze compared with averted gaze within or between groups. Impaired habituation and accentuated sensitization in response to face/eye gaze was distributed across multiple levels of neural processing. These results could help inform interventions, such as desensitization therapy, which may help patients with fragile X syndrome modulate anxiety and arousal associated with eye gaze, thereby improving social functioning.
An fMRI study of emotional face processing in adolescent major depression.
Hall, Leah M J; Klimes-Dougan, Bonnie; Hunt, Ruskin H; Thomas, Kathleen M; Houri, Alaa; Noack, Emily; Mueller, Bryon A; Lim, Kelvin O; Cullen, Kathryn R
2014-10-01
Major depressive disorder (MDD) often begins during adolescence when the brain is still maturing. To better understand the neurobiological underpinnings of MDD early in development, this study examined brain function in response to emotional faces in adolescents with MDD and healthy (HC) adolescents using functional magnetic resonance imaging (fMRI). Thirty-two unmedicated adolescents with MDD and 23 healthy age- and gender-matched controls completed an fMRI task viewing happy and fearful faces. Fronto-limbic regions of interest (ROI; bilateral amygdala, insula, subgenual and rostral anterior cingulate cortices) and whole-brain analyses were conducted to examine between-group differences in brain function. ROI analyses revealed that patients had greater bilateral amygdala activity than HC in response to viewing fearful versus happy faces, which remained significant when controlling for comorbid anxiety. Whole-brain analyses revealed that adolescents with MDD had lower activation compared to HC in a right hemisphere cluster comprised of the insula, superior/middle temporal gyrus, and Heschl׳s gyrus when viewing fearful faces. Brain activity in the subgenual anterior cingulate cortex was inversely correlated with depression severity. Limitations include a cross-sectional design with a modest sample size and use of a limited range of emotional stimuli. Results replicate previous studies that suggest emotion processing in adolescent MDD is associated with abnormalities within fronto-limbic brain regions. Findings implicate elevated amygdalar arousal to negative stimuli in adolescents with depression and provide new evidence for a deficit in functioning of the saliency network, which may be a future target for early intervention and MDD treatment. Copyright © 2014 Elsevier B.V. All rights reserved.
The Coronal Abundance Anomalies of M Dwarfs
NASA Astrophysics Data System (ADS)
Wood, Brian E.; Laming, J. Martin; Karovska, Margarita
2012-07-01
We analyze Chandra X-ray spectra of the M0 V+M0 V binary GJ 338. As quantified by X-ray surface flux, these are the most inactive M dwarfs ever observed with X-ray grating spectroscopy. We focus on measuring coronal abundances, in particular searching for evidence of abundance anomalies related to first ionization potential (FIP). In the solar corona and wind, low-FIP elements are overabundant, which is the so-called FIP effect. For other stars, particularly very active ones, an "inverse FIP effect" is often observed, with low-FIP elements being underabundant. For both members of the GJ 338 binary, we find evidence for a modest inverse FIP effect, consistent with expectations from a previously reported correlation between spectral type and FIP bias. This amounts to strong evidence that all M dwarfs should exhibit the inverse FIP effect phenomenon, not just the active ones. We take the first step toward modeling the inverse FIP phenomenon in M dwarfs, building on past work that has demonstrated that MHD waves coursing through coronal loops can lead to a ponderomotive force that fractionates elements in a manner consistent with the FIP effect. We demonstrate that in certain circumstances this model can also lead to an inverse FIP effect, pointing the way to more detailed modeling of M dwarf coronal abundances in the future.
Jemel, Boutheina; Pisani, Michèle; Calabria, Marco; Crommelinck, Marc; Bruyer, Raymond
2003-07-01
Impoverished images of faces, two-tone Mooney faces, severely impair the ability to recognize to whom the face pertains. However, previously seeing the corresponding face in a clear format helps fame-judgments to Mooney faces. In the present experiment, we sought to demonstrate that enhancement in the perceptual encoding of Mooney faces results from top-down effects, due to previous activation of familiar face representation. Event-related potentials (ERPs) were obtained for target Mooney images of familiar and unfamiliar faces preceded by clear pictures portraying either the same photo (same photo prime), or a different photo of the same person (different photo prime) or a new unfamiliar face (no-prime). In agreement with previous findings the use of primes was effective in enhancing the recognition of familiar faces in Mooney images; this priming effect was larger in the same than in different photo priming condition. ERP data revealed that the amplitude of the N170 face-sensitive component was smaller when elicited by familiar than by unfamiliar face targets, and for familiar face targets primed by the same than by different photos (a graded priming effect). Because the priming effect was restricted to familiar faces and occurred at the peak of the N170, we suggest that the early perceptual stage of face processing is likely to be penetrable by the top-down effect due to the activation of face representations within the face recognition system.
Developing a Near Real-time System for Earthquake Slip Distribution Inversion
NASA Astrophysics Data System (ADS)
Zhao, Li; Hsieh, Ming-Che; Luo, Yan; Ji, Chen
2016-04-01
Advances in observational and computational seismology in the past two decades have enabled completely automatic and real-time determinations of the focal mechanisms of earthquake point sources. However, seismic radiations from moderate and large earthquakes often exhibit strong finite-source directivity effect, which is critically important for accurate ground motion estimations and earthquake damage assessments. Therefore, an effective procedure to determine earthquake rupture processes in near real-time is in high demand for hazard mitigation and risk assessment purposes. In this study, we develop an efficient waveform inversion approach for the purpose of solving for finite-fault models in 3D structure. Full slip distribution inversions are carried out based on the identified fault planes in the point-source solutions. To ensure efficiency in calculating 3D synthetics during slip distribution inversions, a database of strain Green tensors (SGT) is established for 3D structural model with realistic surface topography. The SGT database enables rapid calculations of accurate synthetic seismograms for waveform inversion on a regular desktop or even a laptop PC. We demonstrate our source inversion approach using two moderate earthquakes (Mw~6.0) in Taiwan and in mainland China. Our results show that 3D velocity model provides better waveform fitting with more spatially concentrated slip distributions. Our source inversion technique based on the SGT database is effective for semi-automatic, near real-time determinations of finite-source solutions for seismic hazard mitigation purposes.
Okop, Kufre Joseph; Levitt, Naomi; Puoane, Thandi
2015-01-01
Objective To determine the factors associated with excessive body fat among black African men and women living in rural and urban communities of South Africa. Methods This is a cross-sectional analysis of data from the Prospective Urban and Rural Epidemiology (PURE) study, Cape Town, South Africa conducted in 2009/2010. The study sample included 1220 participants (77.2% women) aged 35–70 years, for whom anthropometric measurements were obtained and risk factors documented through face-to-face interviews using validated international PURE study protocols. Sex-specific logistic regression models were used to evaluate socio-demographic, lifestyle and psychological factors associated with three excessive body fat indicators, namely body mass index (BMI), waist circumference (WC) and body fat percent (BF%). Results The prevalence of excessive body fat based on BF%, WC and BMI cut-offs were 96.0%, 86.1%, and 81.6% for women respectively, and 62.2%, 25.9%, and 36.0% for men respectively. The significant odds of excessive body fat among the currently married compared to unmarried were 4.1 (95% CI: 1.3–12.5) for BF% and 1.9 (95% CI: 1.3–2.9) for BMI among women; and 4.9 (95% CI: 2.6–9.6), 3.2 (95% CI: 1.6–6.4) and 3.6 (95% CI: 1.9–6.8) for BF%, WC and BMI respectively among men. Age ≤50 years (compared to age >50 years) was inversely associated with excessive BF% in men and women, and less-than-a-college education was inversely associated with excessive BMI and WC in men. Tobacco smoking was inversely associated with all three excessive adiposity indicators in women but not in men. Unemployment, depression, and stress did not predict excessive body fat in men or women. Conclusion The sex-differences in the socio-demographic and lifestyle factors associated with the high levels of excessive body fat in urban and rural women and men should be considered in packaging interventions to reduce obesity in these communities. PMID:26447880
Inverse Target- and Cue-Priming Effects of Masked Stimuli
ERIC Educational Resources Information Center
Mattler, Uwe
2007-01-01
The processing of a visual target that follows a briefly presented prime stimulus can be facilitated if prime and target stimuli are similar. In contrast to these positive priming effects, inverse priming effects (or negative compatibility effects) have been found when a mask follows prime stimuli before the target stimulus is presented: Responses…
Inverse opal carbons for counter electrode of dye-sensitized solar cells.
Kang, Da-Young; Lee, Youngshin; Cho, Chang-Yeol; Moon, Jun Hyuk
2012-05-01
We investigated the fabrication of inverse opal carbon counter electrodes using a colloidal templating method for DSSCs. Specifically, bare inverse opal carbon, mesopore-incoporated inverse opal carbon, and graphitized inverse opal carbon were synthesized and stably dispersed in ethanol solution for spray coating on a FTO substrate. The thickness of the electrode was controlled by the number of coatings, and the average relative thickness was evaluated by measuring the transmittance spectrum. The effect of the counter electrode thickness on the photovoltaic performance of the DSSCs was investigated and analyzed by interfacial charge transfer resistance (R(CT)) under EIS measurement. The effect of the surface area and conductivity of the inverse opal was also investigated by considering the increase in surface area due to the mesopore in the inverse opal carbon and conductivity by graphitization of the carbon matrix. The results showed that the FF and thereby the efficiency of DSSCs were increased as the electrode thickness increased. Consequently, the larger FF and thereby the greater efficiency of the DSSCs were achieved for mIOC and gIOC compared to IOC, which was attributed to the lower R(CT). Finally, compared to a conventional Pt counter electrode, the inverse opal-based carbon showed a comparable efficiency upon application to DSSCs.
Effects of face feature and contour crowding in facial expression adaptation.
Liu, Pan; Montaser-Kouhsari, Leila; Xu, Hong
2014-12-01
Prolonged exposure to a visual stimulus, such as a happy face, biases the perception of subsequently presented neutral face toward sad perception, the known face adaptation. Face adaptation is affected by visibility or awareness of the adapting face. However, whether it is affected by discriminability of the adapting face is largely unknown. In the current study, we used crowding to manipulate discriminability of the adapting face and test its effect on face adaptation. Instead of presenting flanking faces near the target face, we shortened the distance between facial features (internal feature crowding), and reduced the size of face contour (external contour crowding), to introduce crowding. We are interested in whether internal feature crowding or external contour crowding is more effective in inducing crowding effect in our first experiment. We found that combining internal feature and external contour crowding, but not either of them alone, induced significant crowding effect. In Experiment 2, we went on further to investigate its effect on adaptation. We found that both internal feature crowding and external contour crowding reduced its facial expression aftereffect (FEA) significantly. However, we did not find a significant correlation between discriminability of the adapting face and its FEA. Interestingly, we found a significant correlation between discriminabilities of the adapting and test faces. Experiment 3 found that the reduced adaptation aftereffect in combined crowding by the external face contour and the internal facial features cannot be decomposed into the effects from the face contour and facial features linearly. It thus suggested a nonlinear integration between facial features and face contour in face adaptation.
NASA Astrophysics Data System (ADS)
Liang, Li-Feng; Zhang, Hong-Bing; Dan, Zhi-Wei; Xu, Zi-Qiang; Liu, Xiu-Juan; Cao, Cheng-Hao
2017-03-01
Simultaneous prestack inversion is based on the modified Fatti equation and uses the ratio of the P- and S-wave velocity as constraints. We use the relation of P-wave impedance and density (PID) and S-wave impedance and density (SID) to replace the constant Vp/Vs constraint, and we propose the improved constrained Fatti equation to overcome the effect of P-wave impedance on density. We compare the sensitivity of both methods using numerical simulations and conclude that the density inversion sensitivity improves when using the proposed method. In addition, the random conjugate-gradient method is used in the inversion because it is fast and produces global solutions. The use of synthetic and field data suggests that the proposed inversion method is effective in conventional and nonconventional lithologies.
anisotropic microseismic focal mechanism inversion by waveform imaging matching
NASA Astrophysics Data System (ADS)
Wang, L.; Chang, X.; Wang, Y.; Xue, Z.
2016-12-01
The focal mechanism is one of the most important parameters in source inversion, for both natural earthquakes and human-induced seismic events. It has been reported to be useful for understanding stress distribution and evaluating the fracturing effect. The conventional focal mechanism inversion method picks the first arrival waveform of P wave. This method assumes the source as a Double Couple (DC) type and the media isotropic, which is usually not the case for induced seismic focal mechanism inversion. For induced seismic events, the inappropriate source and media model in inversion processing, by introducing ambiguity or strong simulation errors, will seriously reduce the inversion effectiveness. First, the focal mechanism contains significant non-DC source type. Generally, the source contains three components: DC, isotropic (ISO) and the compensated linear vector dipole (CLVD), which makes focal mechanisms more complicated. Second, the anisotropy of media will affect travel time and waveform to generate inversion bias. The common way to describe focal mechanism inversion is based on moment tensor (MT) inversion which can be decomposed into the combination of DC, ISO and CLVD components. There are two ways to achieve MT inversion. The wave-field migration method is applied to achieve moment tensor imaging. This method can construct elements imaging of MT in 3D space without picking the first arrival, but the retrieved MT value is influenced by imaging resolution. The full waveform inversion is employed to retrieve MT. In this method, the source position and MT can be reconstructed simultaneously. However, this method needs vast numerical calculation. Moreover, the source position and MT also influence each other in the inversion process. In this paper, the waveform imaging matching (WIM) method is proposed, which combines source imaging with waveform inversion for seismic focal mechanism inversion. Our method uses the 3D tilted transverse isotropic (TTI) elastic wave equation to approximate wave propagating in anisotropic media. First, a source imaging procedure is employed to obtain the source position. Second, we refine a waveform inversion algorithm to retrieve MT. We also use a microseismic data set recorded in surface acquisition to test our method.
Holistic processing is finely tuned for faces of one's own race.
Michel, Caroline; Rossion, Bruno; Han, Jaehyun; Chung, Chan-Sup; Caldara, Roberto
2006-07-01
Recognizing individual faces outside one's race poses difficulty, a phenomenon known as the other-race effect. Most researchers agree that this effect results from differential experience with same-race (SR) and other-race (OR) faces. However, the specific processes that develop with visual experience and underlie the other-race effect remain to be clarified. We tested whether the integration of facial features into a whole representation-holistic processing-was larger for SR than OR faces in Caucasians and Asians without life experience with OR faces. For both classes of participants, recognition of the upper half of a composite-face stimulus was more disrupted by the bottom half (the composite-face effect) for SR than OR faces, demonstrating that SR faces are processed more holistically than OR faces. This differential holistic processing for faces of different races, probably a by-product of visual experience, may be a critical factor in the other-race effect.
Gaze cueing by pareidolia faces.
Takahashi, Kohske; Watanabe, Katsumi
2013-01-01
Visual images that are not faces are sometimes perceived as faces (the pareidolia phenomenon). While the pareidolia phenomenon provides people with a strong impression that a face is present, it is unclear how deeply pareidolia faces are processed as faces. In the present study, we examined whether a shift in spatial attention would be produced by gaze cueing of face-like objects. A robust cueing effect was observed when the face-like objects were perceived as faces. The magnitude of the cueing effect was comparable between the face-like objects and a cartoon face. However, the cueing effect was eliminated when the observer did not perceive the objects as faces. These results demonstrated that pareidolia faces do more than give the impression of the presence of faces; indeed, they trigger an additional face-specific attentional process.
Gaze cueing by pareidolia faces
Takahashi, Kohske; Watanabe, Katsumi
2013-01-01
Visual images that are not faces are sometimes perceived as faces (the pareidolia phenomenon). While the pareidolia phenomenon provides people with a strong impression that a face is present, it is unclear how deeply pareidolia faces are processed as faces. In the present study, we examined whether a shift in spatial attention would be produced by gaze cueing of face-like objects. A robust cueing effect was observed when the face-like objects were perceived as faces. The magnitude of the cueing effect was comparable between the face-like objects and a cartoon face. However, the cueing effect was eliminated when the observer did not perceive the objects as faces. These results demonstrated that pareidolia faces do more than give the impression of the presence of faces; indeed, they trigger an additional face-specific attentional process. PMID:25165505
Gerlach, Christian; Starrfelt, Randi
2018-03-20
There has been an increase in studies adopting an individual difference approach to examine visual cognition and in particular in studies trying to relate face recognition performance with measures of holistic processing (the face composite effect and the part-whole effect). In the present study we examine whether global precedence effects, measured by means of non-face stimuli in Navon's paradigm, can also account for individual differences in face recognition and, if so, whether the effect is of similar magnitude for faces and objects. We find evidence that global precedence effects facilitate both face and object recognition, and to a similar extent. Our results suggest that both face and object recognition are characterized by a coarse-to-fine temporal dynamic, where global shape information is derived prior to local shape information, and that the efficiency of face and object recognition is related to the magnitude of the global precedence effect.
Investigating source processes of isotropic events
NASA Astrophysics Data System (ADS)
Chiang, Andrea
This dissertation demonstrates the utility of the complete waveform regional moment tensor inversion for nuclear event discrimination. I explore the source processes and associated uncertainties for explosions and earthquakes under the effects of limited station coverage, compound seismic sources, assumptions in velocity models and the corresponding Green's functions, and the effects of shallow source depth and free-surface conditions. The motivation to develop better techniques to obtain reliable source mechanism and assess uncertainties is not limited to nuclear monitoring, but they also provide quantitative information about the characteristics of seismic hazards, local and regional tectonics and in-situ stress fields of the region . This dissertation begins with the analysis of three sparsely recorded events: the 14 September 1988 US-Soviet Joint Verification Experiment (JVE) nuclear test at the Semipalatinsk test site in Eastern Kazakhstan, and two nuclear explosions at the Chinese Lop Nor test site. We utilize a regional distance seismic waveform method fitting long-period, complete, three-component waveforms jointly with first-motion observations from regional stations and teleseismic arrays. The combination of long period waveforms and first motion observations provides unique discrimination of these sparsely recorded events in the context of the Hudson et al. (1989) source-type diagram. We examine the effects of the free surface on the moment tensor via synthetic testing, and apply the moment tensor based discrimination method to well-recorded chemical explosions. These shallow chemical explosions represent rather severe source-station geometry in terms of the vanishing traction issues. We show that the combined waveform and first motion method enables the unique discrimination of these events, even though the data include unmodeled single force components resulting from the collapse and blowout of the quarry face immediately following the initial explosion. In contrast, recovering the announced explosive yield using seismic moment estimates from moment tensor inversion remains challenging but we can begin to put error bounds on our moment estimates using the NSS technique. The estimation of seismic source parameters is dependent upon having a well-calibrated velocity model to compute the Green's functions for the inverse problem. Ideally, seismic velocity models are calibrated through broadband waveform modeling, however in regions of low seismicity velocity models derived from body or surface wave tomography may be employed. Whether a velocity model is 1D or 3D, or based on broadband seismic waveform modeling or the various tomographic techniques, the uncertainty in the velocity model can be the greatest source of error in moment tensor inversion. These errors have not been fully investigated for the nuclear discrimination problem. To study the effects of unmodeled structures on the moment tensor inversion, we set up a synthetic experiment where we produce synthetic seismograms for a 3D model (Moschetti et al., 2010) and invert these data using Green's functions computed with a 1D velocity mode (Song et al., 1996) to evaluate the recoverability of input solutions, paying particular attention to biases in the isotropic component. The synthetic experiment results indicate that the 1D model assumption is valid for moment tensor inversions at periods as short as 10 seconds for the 1D western U.S. model (Song et al., 1996). The correct earthquake mechanisms and source depth are recovered with statistically insignificant isotropic components as determined by the F-test. Shallow explosions are biased by the theoretical ISO-CLVD tradeoff but the tectonic release component remains low, and the tradeoff can be eliminated with constraints from P wave first motion. Path-calibration to the 1D model can reduce non-double-couple components in earthquakes, non-isotropic components in explosions and composite sources and improve the fit to the data. When we apply the 3D model to real data, at long periods (20-50 seconds), we see good agreement in the solutions between the 1D and 3D models and slight improvement in waveform fits when using the 3D velocity model Green's functions. (Abstract shortened by ProQuest.).
Implanting Strong Spin-Orbit Coupling at Magnetoelectric Interfaces
2017-12-19
one is polar. Because the broken inversion symmetry in the polar structure is driven by a combination of the Sr-Ca cation mismatch and the octahedral...ME coefficient without breaking the inversion symmetry manifest a large boost of the ME effect with strong spin-orbit coupling. Results on the polar... inversion center. These peaks are absent in the nonpolar structure and appear here due to the A-site ordering and the resulting inversion symmetry
Race coding and the other-race effect in face recognition.
Rhodes, Gillian; Locke, Vance; Ewing, Louise; Evangelista, Emma
2009-01-01
Other-race faces are generally recognised more poorly than own-race faces. According to Levin's influential race-coding hypothesis, this other-race recognition deficit results from spontaneous coding of race-specifying information, at the expense of individuating information, in other-race faces. Therefore, requiring participants to code race-specifying information for all faces should eliminate the other-race effect by reducing recognition of own-race faces to the level of other-race faces. We tested this prediction in two experiments. Race coding was induced by requiring participants to rate study faces on race typicality (experiment 1) or to categorise them by race (experiment 2). Neither manipulation reduced the other-race effect, providing no support for the race-coding hypothesis. Instead, race-coding instructions marginally increased the other-race effect in experiment 1 and had no effect in experiment 2. These results do not support the race-coding hypothesis. Surprisingly, a control task of rating the attractiveness of study faces increased the other-race effect, indicating that deeper encoding of faces does not necessarily reduce the effect (experiment 1). Finally, the normally robust other-race effect was absent when participants were instructed to individuate other-race faces (experiment 2). We suggest that poorer recognition of other-race faces may reflect reduced perceptual expertise with such faces and perhaps reduced motivation to individuate them.
Klinck, Mary P; Rialland, Pascale; Guillot, Martin; Moreau, Maxim; Frank, Diane; Troncy, Eric
2015-12-02
Subtle signs and conflicting physical and radiographic findings make feline osteoarthritis (OA) challenging to diagnose. A physical examination-based assessment was developed, consisting of eight items: Interaction, Exploration, Posture, Gait, Body Condition, Coat and Claws, (joint) Palpation-Findings, and Palpation-Cat Reaction. Content (experts) and face (veterinary students) validity were excellent. Construct validity, internal consistency, and intra- and inter-rater reliability were assessed via a pilot and main study, using laboratory-housed cats with and without OA. Gait distinguished OA status in the pilot ( p = 0.05) study. In the main study, no scale item achieved statistically significant OA detection. Forelimb peak vertical ground reaction force (PVF) correlated inversely with Gait (Rho s = -0.38 ( p = 0.03) to -0.41 ( p = 0.02)). Body Posture correlated with Gait, and inversely with forelimb PVF at two of three time points (Rho s = -0.38 ( p = 0.03) to -0.43 ( p = 0.01)). Palpation (Findings, Cat Reaction) did not distinguish OA from non-OA cats. Palpation-Cat Reaction (Forelimbs) correlated inversely with forelimb PVF at two time points (Rho s = -0.41 ( p = 0.02) to -0.41 ( p = 0.01)), but scores were highly variable, and poorly reliable. Gait and Posture require improved sensitivity, and Palpation should be interpreted cautiously, in diagnosing feline OA.
Classification of rollovers according to crash severity.
Digges, K; Eigen, A
2006-01-01
NASS/CDS 1995-2004 was used to classify rollovers according to severity. The rollovers were partitioned into two classes - rollover as the first event and rollover preceded by an impact with a fixed or non-fixed object. The populations of belted and unbelted were examined separately and combined. The average injury rate for the unbelted was five times that for the belted. Approximately 21% of the severe injuries suffered by belted occupants were in crashes with harmful events prior to the rollover that produced severe damage to the vehicle. This group carried a much higher injury risk than the average. A planar damage measure in addition to the rollover measure was required to adequately capture the crash severity of this population. For rollovers as the first event, approximately 1% of the serious injuries to belted occupants occurred during the first quarter-turn. Rollovers that were arrested during the 1 ( st ) quarter-turn carried a higher injury rate than average. The number of quarter-turns were grouped in various ways including the number of times the vehicle roof faces the ground (number of vehicle inversions). The number of vehicle inversions was found to be a statistically significant injury predictor for 78% of the belted and unbelted populations with MAIS 3+F injuries in rollovers. The remaining 22% required crash severity metrics in addition to the number of vehicle inversions.
Inverting dedevelopment: geometric singularity theory in embryology
NASA Astrophysics Data System (ADS)
Bookstein, Fred L.; Smith, Bradley R.
2000-10-01
The diffeomorphism model so useful in the biomathematics of normal morphological variability and disease is inappropriate for applications in embryogenesis, where whole coordinate patches are created out of single points. For this application we need a suitable algebra for the creation of something from nothing in a carefully organized geometry: a formalism for parameterizing discrete nondifferentiabilities of invertible functions on Rk, k $GTR 1. One easy way to begin is via the inverse of the development map - call it the dedevelopment map, the deformation backwards in time. Extrapolated, this map will inevitably have singularities at which its derivative is zero. When the dedevelopment map is inverted to face forward in time, the singularities become appropriately isolated infinities of derivative. We have recently introduced growth visualizations via extrapolations to the isolated singularities at which only one directional derivative is zero. Maps inverse to these create new coordinate patches directionally rather than radically. The most generic singularity that suits this purpose is the crease f(x,y) equals (x,x2y+y3), which has already been applied in morphometrics for the description of focal morphogenetic phenomena. We apply it to embryogenesis in the form of its analytic inverse, and demonstrate its power using a priceless new data set of mouse embryos imaged in 3D by micro-MR with voxels smaller than 100micrometers 3.
Classification of Rollovers According to Crash Severity
Digges, K.; Eigen, A.
2006-01-01
NASS/CDS 1995–2004 was used to classify rollovers according to severity. The rollovers were partitioned into two classes – rollover as the first event and rollover preceded by an impact with a fixed or non-fixed object. The populations of belted and unbelted were examined separately and combined. The average injury rate for the unbelted was five times that for the belted. Approximately 21% of the severe injuries suffered by belted occupants were in crashes with harmful events prior to the rollover that produced severe damage to the vehicle. This group carried a much higher injury risk than the average. A planar damage measure in addition to the rollover measure was required to adequately capture the crash severity of this population. For rollovers as the first event, approximately 1% of the serious injuries to belted occupants occurred during the first quarter-turn. Rollovers that were arrested during the 1st quarter-turn carried a higher injury rate than average. The number of quarter-turns were grouped in various ways including the number of times the vehicle roof faces the ground (number of vehicle inversions). The number of vehicle inversions was found to be a statistically significant injury predictor for 78% of the belted and unbelted populations with MAIS 3+F injuries in rollovers. The remaining 22% required crash severity metrics in addition to the number of vehicle inversions. PMID:16968634
Investigation of inversion polymorphisms in the human genome using principal components analysis.
Ma, Jianzhong; Amos, Christopher I
2012-01-01
Despite the significant advances made over the last few years in mapping inversions with the advent of paired-end sequencing approaches, our understanding of the prevalence and spectrum of inversions in the human genome has lagged behind other types of structural variants, mainly due to the lack of a cost-efficient method applicable to large-scale samples. We propose a novel method based on principal components analysis (PCA) to characterize inversion polymorphisms using high-density SNP genotype data. Our method applies to non-recurrent inversions for which recombination between the inverted and non-inverted segments in inversion heterozygotes is suppressed due to the loss of unbalanced gametes. Inside such an inversion region, an effect similar to population substructure is thus created: two distinct "populations" of inversion homozygotes of different orientations and their 1:1 admixture, namely the inversion heterozygotes. This kind of substructure can be readily detected by performing PCA locally in the inversion regions. Using simulations, we demonstrated that the proposed method can be used to detect and genotype inversion polymorphisms using unphased genotype data. We applied our method to the phase III HapMap data and inferred the inversion genotypes of known inversion polymorphisms at 8p23.1 and 17q21.31. These inversion genotypes were validated by comparing with literature results and by checking Mendelian consistency using the family data whenever available. Based on the PCA-approach, we also performed a preliminary genome-wide scan for inversions using the HapMap data, which resulted in 2040 candidate inversions, 169 of which overlapped with previously reported inversions. Our method can be readily applied to the abundant SNP data, and is expected to play an important role in developing human genome maps of inversions and exploring associations between inversions and susceptibility of diseases.
A theory of the inverse magnetoelectric effect in layered magnetostrictive-piezoelectric structures
NASA Astrophysics Data System (ADS)
Filippov, D. A.; Radchenko, G. S.; Firsova, T. O.; Galkina, T. A.
2017-05-01
A theory of the inverse magnetoelectric effect in layered structures has been presented. The theory is based on solving the equations of elastodynamics and electrostatics separately for the magnetostrictive and piezoelectric phases, taking into account the conditions at the interface between the phases. Expressions for the coefficient of inverse magnetoelectric conversion through the parameters characterizing the magnetostrictive and piezoelectric phases have been obtained. Theoretical dependences of the inverse magnetoelectric conversion coefficient on the frequency of the alternating-current electric field for the three-layer PZT-Ni-PZT structure and the two-layer terfenol- D-PZT structure have been calculated. The results of the calculations are in good agreement with the experimental data.
Gender-based prototype formation in face recognition.
Baudouin, Jean-Yves; Brochard, Renaud
2011-07-01
The role of gender categories in prototype formation during face recognition was investigated in 2 experiments. The participants were asked to learn individual faces and then to recognize them. During recognition, individual faces were mixed with faces, which were blended faces of same or different genders. The results of the 2 experiments showed that blended faces made with learned individual faces were recognized, even though they had never been seen before. In Experiment 1, this effect was stronger when faces belonged to the same gender category (same-sex blended faces), but it also emerged across gender categories (cross-sex blended faces). Experiment 2 further showed that this prototype effect was not affected by the presentation order for same-sex blended faces: The effect was equally strong when the faces were presented one after the other during learning or alternated with faces of the opposite gender. By contrast, the prototype effect across gender categories was highly sensitive to the temporal proximity of the faces blended into the blended faces and almost disappeared when other faces were intermixed. These results indicate that distinct neural populations code for female and male faces. However, the formation of a facial representation can also be mediated by both neural populations. The implications for face-space properties and face-encoding processes are discussed.
Multi-scale signed envelope inversion
NASA Astrophysics Data System (ADS)
Chen, Guo-Xin; Wu, Ru-Shan; Wang, Yu-Qing; Chen, Sheng-Chang
2018-06-01
Envelope inversion based on modulation signal mode was proposed to reconstruct large-scale structures of underground media. In order to solve the shortcomings of conventional envelope inversion, multi-scale envelope inversion was proposed using new envelope Fréchet derivative and multi-scale inversion strategy to invert strong contrast models. In multi-scale envelope inversion, amplitude demodulation was used to extract the low frequency information from envelope data. However, only to use amplitude demodulation method will cause the loss of wavefield polarity information, thus increasing the possibility of inversion to obtain multiple solutions. In this paper we proposed a new demodulation method which can contain both the amplitude and polarity information of the envelope data. Then we introduced this demodulation method into multi-scale envelope inversion, and proposed a new misfit functional: multi-scale signed envelope inversion. In the numerical tests, we applied the new inversion method to the salt layer model and SEG/EAGE 2-D Salt model using low-cut source (frequency components below 4 Hz were truncated). The results of numerical test demonstrated the effectiveness of this method.
Human inversions and their functional consequences
Puig, Marta; Casillas, Sònia; Villatoro, Sergi
2015-01-01
Polymorphic inversions are a type of structural variants that are difficult to analyze owing to their balanced nature and the location of breakpoints within complex repeated regions. So far, only a handful of inversions have been studied in detail in humans and current knowledge about their possible functional effects is still limited. However, inversions have been related to phenotypic changes and adaptation in multiple species. In this review, we summarize the evidences of the functional impact of inversions in the human genome. First, given that inversions have been shown to inhibit recombination in heterokaryotes, chromosomes displaying different orientation are expected to evolve independently and this may lead to distinct gene-expression patterns. Second, inversions have a role as disease-causing mutations both by directly affecting gene structure or regulation in different ways, and by predisposing to other secondary arrangements in the offspring of inversion carriers. Finally, several inversions show signals of being selected during human evolution. These findings illustrate the potential of inversions to have phenotypic consequences also in humans and emphasize the importance of their inclusion in genome-wide association studies. PMID:25998059
Kindling and withdrawal changes at the benzodiazepine receptor.
Little, H J; Nutt, D J; Taylor, S C
1987-01-01
Drugs acting at benzodiazepine receptors can have two types of pharmacological profile: benzodiazepine agonists are anxiolytic, anticonvulsant and sedative, whilst benzo diazepine inverse agonists cause anxiety and convulsions. In 1982 we showed that a benzo diazepine antagonist, Ro 15-1788, prevented the effects of both types of compound at doses without intrinsic activity in the tests used. We put forward the hypothesis that the benzo diazepine receptor complex could undergo two possible conformational changes, resulting in increases (benzodiazepine agonists) or decreases (benzodiazepine inverse agonists) in the effects of the inhibitory transmitter γ-aminobutyric acid (GABA). This concept has been widely accepted. We have now studied the effects of inverse agonists after chronic treatment with inverse agonists themselves and with benzodiazepine agonists, in order to see if tolerance develops (as seen with the agonists) or whether an opposite change occurs.
A theoretical formulation of the electrophysiological inverse problem on the sphere
NASA Astrophysics Data System (ADS)
Riera, Jorge J.; Valdés, Pedro A.; Tanabe, Kunio; Kawashima, Ryuta
2006-04-01
The construction of three-dimensional images of the primary current density (PCD) produced by neuronal activity is a problem of great current interest in the neuroimaging community, though being initially formulated in the 1970s. There exist even now enthusiastic debates about the authenticity of most of the inverse solutions proposed in the literature, in which low resolution electrical tomography (LORETA) is a focus of attention. However, in our opinion, the capabilities and limitations of the electro and magneto encephalographic techniques to determine PCD configurations have not been extensively explored from a theoretical framework, even for simple volume conductor models of the head. In this paper, the electrophysiological inverse problem for the spherical head model is cast in terms of reproducing kernel Hilbert spaces (RKHS) formalism, which allows us to identify the null spaces of the implicated linear integral operators and also to define their representers. The PCD are described in terms of a continuous basis for the RKHS, which explicitly separates the harmonic and non-harmonic components. The RKHS concept permits us to bring LORETA into the scope of the general smoothing splines theory. A particular way of calculating the general smoothing splines is illustrated, avoiding a brute force discretization prematurely. The Bayes information criterion is used to handle dissimilarities in the signal/noise ratios and physical dimensions of the measurement modalities, which could affect the estimation of the amount of smoothness required for that class of inverse solution to be well specified. In order to validate the proposed method, we have estimated the 3D spherical smoothing splines from two data sets: electric potentials obtained from a skull phantom and magnetic fields recorded from subjects performing an experiment of human faces recognition.
NASA Astrophysics Data System (ADS)
Stritzel, J.; Melchert, O.; Wollweber, M.; Roth, B.
2017-09-01
The direct problem of optoacoustic signal generation in biological media consists of solving an inhomogeneous three-dimensional (3D) wave equation for an initial acoustic stress profile. In contrast, the more defiant inverse problem requires the reconstruction of the initial stress profile from a proper set of observed signals. In this article, we consider an effectively 1D approach, based on the assumption of a Gaussian transverse irradiation source profile and plane acoustic waves, in which the effects of acoustic diffraction are described in terms of a linear integral equation. The respective inverse problem along the beam axis can be cast into a Volterra integral equation of the second kind for which we explore here efficient numerical schemes in order to reconstruct initial stress profiles from observed signals, constituting a methodical progress of computational aspects of optoacoustics. In this regard, we explore the validity as well as the limits of the inversion scheme via numerical experiments, with parameters geared toward actual optoacoustic problem instances. The considered inversion input consists of synthetic data, obtained in terms of the effectively 1D approach, and, more generally, a solution of the 3D optoacoustic wave equation. Finally, we also analyze the effect of noise and different detector-to-sample distances on the optoacoustic signal and the reconstructed pressure profiles.
Li, Jin; Huang, Lijie; Song, Yiying; Liu, Jia
2017-07-28
It has been long proposed that our extraordinary face recognition ability stems from holistic face processing. Two widely-used behavioral hallmarks of holistic face processing are the whole-part effect (WPE) and composite-face effect (CFE). However, it remains unknown whether these two effects reflect similar or different aspects of holistic face processing. Here we investigated this question by examining whether the WPE and CFE involved shared or distinct neural substrates in a large sample of participants (N=200). We found that the WPE and CFE showed hemispheric dissociation in the fusiform face area (FFA), that is, the WPE was correlated with face selectivity in the left FFA, while the CFE was correlated with face selectivity in the right FFA. Further, the correlation between the WPE and face selectivity was largely driven by the FFA response to faces, whereas the association between the CFE and face selectivity resulted from suppressed response to objects in the right FFA. Finally, we also observed dissociated correlation patterns of the WPE and CFE in other face-selective regions and across the whole brain. These results suggest that the WPE and CFE may reflect different aspects of holistic face processing, which shed new light on the behavioral dissociations of these two effects demonstrated in literature. Copyright © 2017 Elsevier Ltd. All rights reserved.
Kim, Ok-Hee; Cho, Yong-Hun; Kang, Soon Hyung; Park, Hee-Young; Kim, Minhyoung; Lim, Ju Wan; Chung, Dong Young; Lee, Myeong Jae; Choe, Heeman; Sung, Yung-Eun
2013-01-01
Three-dimensional, ordered macroporous materials such as inverse opal structures are attractive materials for various applications in electrochemical devices because of the benefits derived from their periodic structures: relatively large surface areas, large voidage, low tortuosity and interconnected macropores. However, a direct application of an inverse opal structure in membrane electrode assemblies has been considered impractical because of the limitations in fabrication routes including an unsuitable substrate. Here we report the demonstration of a single cell that maintains an inverse opal structure entirely within a membrane electrode assembly. Compared with the conventional catalyst slurry, an ink-based assembly, this modified assembly has a robust and integrated configuration of catalyst layers; therefore, the loss of catalyst particles can be minimized. Furthermore, the inverse-opal-structure electrode maintains an effective porosity, an enhanced performance, as well as an improved mass transfer and more effective water management, owing to its morphological advantages.
Alzheimer's disease: the amyloid hypothesis and the Inverse Warburg effect
Demetrius, Lloyd A.; Magistretti, Pierre J.; Pellerin, Luc
2014-01-01
Epidemiological and biochemical studies show that the sporadic forms of Alzheimer's disease (AD) are characterized by the following hallmarks: (a) An exponential increase with age; (b) Selective neuronal vulnerability; (c) Inverse cancer comorbidity. The present article appeals to these hallmarks to evaluate and contrast two competing models of AD: the amyloid hypothesis (a neuron-centric mechanism) and the Inverse Warburg hypothesis (a neuron-astrocytic mechanism). We show that these three hallmarks of AD conflict with the amyloid hypothesis, but are consistent with the Inverse Warburg hypothesis, a bioenergetic model which postulates that AD is the result of a cascade of three events—mitochondrial dysregulation, metabolic reprogramming (the Inverse Warburg effect), and natural selection. We also provide an explanation for the failures of the clinical trials based on amyloid immunization, and we propose a new class of therapeutic strategies consistent with the neuroenergetic selection model. PMID:25642192
Methods to control phase inversions and enhance mass transfer in liquid-liquid dispersions
Tsouris, Constantinos; Dong, Junhang
2002-01-01
The present invention is directed to the effects of applied electric fields on liquid-liquid dispersions. In general, the present invention is directed to the control of phase inversions in liquid-liquid dispersions. Because of polarization and deformation effects, coalescence of aqueous drops is facilitated by the application of electric fields. As a result, with an increase in the applied voltage, the ambivalence region is narrowed and shifted toward higher volume fractions of the dispersed phase. This permits the invention to be used to ensure that the aqueous phase remains continuous, even at a high volume fraction of the organic phase. Additionally, the volume fraction of the organic phase may be increased without causing phase inversion, and may be used to correct a phase inversion which has already occurred. Finally, the invention may be used to enhance mass transfer rates from one phase to another through the use of phase inversions.
Computational inverse methods of heat source in fatigue damage problems
NASA Astrophysics Data System (ADS)
Chen, Aizhou; Li, Yuan; Yan, Bo
2018-04-01
Fatigue dissipation energy is the research focus in field of fatigue damage at present. It is a new idea to solve the problem of calculating fatigue dissipation energy by introducing inverse method of heat source into parameter identification of fatigue dissipation energy model. This paper introduces the research advances on computational inverse method of heat source and regularization technique to solve inverse problem, as well as the existing heat source solution method in fatigue process, prospects inverse method of heat source applying in fatigue damage field, lays the foundation for further improving the effectiveness of fatigue dissipation energy rapid prediction.
NASA Astrophysics Data System (ADS)
Dahanayaka, Daminda; Wong, Andrew; Kaszuba, Philip; Moszkowicz, Leon; Slinkman, James; IBM SPV Lab Team
2014-03-01
Silicon-On-Insulator (SOI) technology has proved beneficial for RF cell phone technologies, which have equivalent performance to GaAs technologies. However, there is evident parasitic inversion layer under the Buried Oxide (BOX) at the interface with the high resistivity Si substrate. The latter is inferred from capacitance-voltage measurements on MOSCAPs. The inversion layer has adverse effects on RF device performance. We present data which, for the first time, show the extent of the inversion layer in the underlying substrate. This knowledge has driven processing techniques to suppress the inversion.
Shumeta, Zekarias; D'Haese, Marijke
2018-06-01
Most coffee in Ethiopia is produced by smallholder farmers who face a daily struggle to get sufficient income but also to feed their families. At the same time, many smallholder coffee producers are members of cooperatives. Yet, literature has paid little attention to the effect of cooperatives on combating food insecurity among cash crop producers including coffee farmers. The objective of the study was to investigate how coffee cooperative membership may affect food security among coffee farm households in Southwest Ethiopia. The study used cross-sectional household data on income, expenditure on food, staple food production (maize and teff), and utilization of improved inputs (fertilizer and improved seed) collected from 256 randomly selected farm households (132 cooperative members and 124 nonmembers) and applied an inverse probability weighting (IPW) estimation to assess the impact of cooperative membership on food security. The result revealed that cooperative membership has a positive and significant effect on staple food production (maize and teff) and facilitated technological transformation via increased utilization of fertilizer and improved seeds. Nonetheless, the effect on food expenditure and income could not be confirmed. Findings suggest a trade-off between coffee marketing and input supply functions of the cooperatives, impairing their true food security impact from the pooled income and production effect.
The impact of profitability of hospital admissions on mortality.
Lindrooth, Richard C; Konetzka, R Tamara; Navathe, Amol S; Zhu, Jingsan; Chen, Wei; Volpp, Kevin
2013-04-01
Fiscal constraints faced by Medicare are leading to policies designed to reduce expenditures. Evidence of the effect of reduced reimbursement on the mortality of Medicare patients discharged from all major hospital service lines is limited. We modeled risk-adjusted 30-day mortality of patients discharged from 21 hospital service lines as a function of service line profitability, service line time trends, and hospital service line and year-fixed effects. We simulated the effect of alternative revenue-neutral reimbursement policies on mortality. Our sample included all Medicare discharges from PPS-eligible hospitals (1997, 2001, and 2005). The results reveal a statistically significant inverse relationship between changes in profitability and mortality. A $0.19 average reduction in profit per $1.00 of costs led to a 0.010-0.020 percentage-point increase in mortality rates (p < .001). Mortality in newly unprofitable service lines is significantly more sensitive to reduced payment generosity than in service lines that remain profitable. Policy simulations that target service line inequities in payment generosity result in lower mortality rates, roughly 700-13,000 fewer deaths nationally. The policy simulations raise questions about the trade-offs implicit in universal reductions in reimbursement. The effect of reduced payment generosity on mortality could be mitigated by targeting highly profitable services only for lower reimbursement. © Health Research and Educational Trust.
The Impact of Profitability of Hospital Admissions on Mortality
Lindrooth, Richard C; Konetzka, R Tamara; Navathe, Amol S; Zhu, Jingsan; Chen, Wei; Volpp, Kevin
2013-01-01
Background Fiscal constraints faced by Medicare are leading to policies designed to reduce expenditures. Evidence of the effect of reduced reimbursement on the mortality of Medicare patients discharged from all major hospital service lines is limited. Methods We modeled risk-adjusted 30-day mortality of patients discharged from 21 hospital service lines as a function of service line profitability, service line time trends, and hospital service line and year-fixed effects. We simulated the effect of alternative revenue-neutral reimbursement policies on mortality. Our sample included all Medicare discharges from PPS-eligible hospitals (1997, 2001, and 2005). Results The results reveal a statistically significant inverse relationship between changes in profitability and mortality. A $0.19 average reduction in profit per $1.00 of costs led to a 0.010–0.020 percentage-point increase in mortality rates (p < .001). Mortality in newly unprofitable service lines is significantly more sensitive to reduced payment generosity than in service lines that remain profitable. Policy simulations that target service line inequities in payment generosity result in lower mortality rates, roughly 700–13,000 fewer deaths nationally. Conclusions The policy simulations raise questions about the trade-offs implicit in universal reductions in reimbursement. The effect of reduced payment generosity on mortality could be mitigated by targeting highly profitable services only for lower reimbursement. PMID:23346946
Surface diffusion of CO on silica-supported Ru particles: 13C nuclear magnetic resonance studies
NASA Astrophysics Data System (ADS)
Duncan, T. M.; Thayer, A. M.; Root, T. W.
1990-02-01
Portions of CO adsorbed on Ru particles, selected by the orientation of the C-O bond relative to an external magnetic field, are labeled by inversion of the 13C nuclear magnetic dipole. Changes in the orientation of the CO bond of these labeled molecules are then observed with 13C NMR spectroscopy. The temperature dependence and rate of reorientation are consistent with surface diffusion on Ru particles with small numbers of flat faces. The insensitivity to CO pressure in the range 0.5-100 Torr discounts stimulated desorption by gas-phase CO.
Dettmer, Jan; Dosso, Stan E; Holland, Charles W
2008-03-01
This paper develops a joint time/frequency-domain inversion for high-resolution single-bounce reflection data, with the potential to resolve fine-scale profiles of sediment velocity, density, and attenuation over small seafloor footprints (approximately 100 m). The approach utilizes sequential Bayesian inversion of time- and frequency-domain reflection data, employing ray-tracing inversion for reflection travel times and a layer-packet stripping method for spherical-wave reflection-coefficient inversion. Posterior credibility intervals from the travel-time inversion are passed on as prior information to the reflection-coefficient inversion. Within the reflection-coefficient inversion, parameter information is passed from one layer packet inversion to the next in terms of marginal probability distributions rotated into principal components, providing an efficient approach to (partially) account for multi-dimensional parameter correlations with one-dimensional, numerical distributions. Quantitative geoacoustic parameter uncertainties are provided by a nonlinear Gibbs sampling approach employing full data error covariance estimation (including nonstationary effects) and accounting for possible biases in travel-time picks. Posterior examination of data residuals shows the importance of including data covariance estimates in the inversion. The joint inversion is applied to data collected on the Malta Plateau during the SCARAB98 experiment.
NASA Astrophysics Data System (ADS)
Sun, Jiajia; Li, Yaoguo
2017-02-01
Joint inversion that simultaneously inverts multiple geophysical data sets to recover a common Earth model is increasingly being applied to exploration problems. Petrophysical data can serve as an effective constraint to link different physical property models in such inversions. There are two challenges, among others, associated with the petrophysical approach to joint inversion. One is related to the multimodality of petrophysical data because there often exist more than one relationship between different physical properties in a region of study. The other challenge arises from the fact that petrophysical relationships have different characteristics and can exhibit point, linear, quadratic, or exponential forms in a crossplot. The fuzzy c-means (FCM) clustering technique is effective in tackling the first challenge and has been applied successfully. We focus on the second challenge in this paper and develop a joint inversion method based on variations of the FCM clustering technique. To account for the specific shapes of petrophysical relationships, we introduce several different fuzzy clustering algorithms that are capable of handling different shapes of petrophysical relationships. We present two synthetic and one field data examples and demonstrate that, by choosing appropriate distance measures for the clustering component in the joint inversion algorithm, the proposed joint inversion method provides an effective means of handling common petrophysical situations we encounter in practice. The jointly inverted models have both enhanced structural similarity and increased petrophysical correlation, and better represent the subsurface in the spatial domain and the parameter domain of physical properties.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gao Yajun
A previously established Hauser-Ernst-type extended double-complex linear system is slightly modified and used to develop an inverse scattering method for the stationary axisymmetric general symplectic gravity model. The reduction procedures in this inverse scattering method are found to be fairly simple, which makes the inverse scattering method applied fine and effective. As an application, a concrete family of soliton double solutions for the considered theory is obtained.
Step-to-Step Ankle Inversion/Eversion Torque Modulation Can Reduce Effort Associated with Balance.
Kim, Myunghee; Collins, Steven H
2017-01-01
Below-knee amputation is associated with higher energy expenditure during walking, partially due to difficulty maintaining balance. We previously found that once-per-step push-off work control can reduce balance-related effort, both in simulation and in experiments with human participants. Simulations also suggested that changing ankle inversion/eversion torque on each step, in response to changes in body state, could assist with balance. In this study, we investigated the effects of ankle inversion/eversion torque modulation on balance-related effort among amputees ( N = 5) using a multi-actuated ankle-foot prosthesis emulator. In stabilizing conditions, changes in ankle inversion/eversion torque were applied so as to counteract deviations in side-to-side center-of-mass acceleration at the moment of intact-limb toe off; higher acceleration toward the prosthetic limb resulted in a corrective ankle inversion torque during the ensuing stance phase. Destabilizing controllers had the opposite effect, and a zero gain controller made no changes to the nominal inversion/eversion torque. To separate the balance-related effects of step-to-step control from the potential effects of changes in average mechanics, average ankle inversion/eversion torque and prosthesis work were held constant across conditions. High-gain stabilizing control lowered metabolic cost by 13% compared to the zero gain controller ( p = 0.05). We then investigated individual responses to subject-specific stabilizing controllers following an enforced exploration period. Four of five participants experienced reduced metabolic rate compared to the zero gain controller (-15, -14, -11, -6, and +4%) an average reduction of 9% ( p = 0.05). Average prosthesis mechanics were unchanged across all conditions, suggesting that improvements in energy economy might have come from changes in step-to-step corrections related to balance. Step-to-step modulation of inversion/eversion torque could be used in new, active ankle-foot prostheses to reduce walking effort associated with maintaining balance.
Easy way to determine quantitative spatial resolution distribution for a general inverse problem
NASA Astrophysics Data System (ADS)
An, M.; Feng, M.
2013-12-01
The spatial resolution computation of a solution was nontrivial and more difficult than solving an inverse problem. Most geophysical studies, except for tomographic studies, almost uniformly neglect the calculation of a practical spatial resolution. In seismic tomography studies, a qualitative resolution length can be indicatively given via visual inspection of the restoration of a synthetic structure (e.g., checkerboard tests). An effective strategy for obtaining quantitative resolution length is to calculate Backus-Gilbert resolution kernels (also referred to as a resolution matrix) by matrix operation. However, not all resolution matrices can provide resolution length information, and the computation of resolution matrix is often a difficult problem for very large inverse problems. A new class of resolution matrices, called the statistical resolution matrices (An, 2012, GJI), can be directly determined via a simple one-parameter nonlinear inversion performed based on limited pairs of random synthetic models and their inverse solutions. The total procedure were restricted to forward/inversion processes used in the real inverse problem and were independent of the degree of inverse skill used in the solution inversion. Spatial resolution lengths can be directly given during the inversion. Tests on 1D/2D/3D model inversion demonstrated that this simple method can be at least valid for a general linear inverse problem.
ERIC Educational Resources Information Center
Siler, Stephanie Ann; VanLehn, Kurt
2009-01-01
Face-to-face (FTF) human-human tutoring has ranked among the most effective forms of instruction. However, because computer-mediated (CM) tutoring is becoming increasingly common, it is instructive to evaluate its effectiveness relative to face-to-face tutoring. Does the lack of spoken, face-to-face interaction affect learning gains and…
NASA Astrophysics Data System (ADS)
Zhou, Junjie; Meng, Xiaohong; Guo, Lianghui; Zhang, Sheng
2015-08-01
Three-dimensional cross-gradient joint inversion of gravity and magnetic data has the potential to acquire improved density and magnetization distribution information. This method usually adopts the commonly held assumption that remanent magnetization can be ignored and all anomalies present are the result of induced magnetization. Accordingly, this method might fail to produce accurate results where significant remanent magnetization is present. In such a case, the simplification brings about unwanted and unknown deviations in the inverted magnetization model. Furthermore, because of the information transfer mechanism of the joint inversion framework, the inverted density results may also be influenced by the effect of remanent magnetization. The normalized magnetic source strength (NSS) is a transformed quantity that is insensitive to the magnetization direction. Thus, it has been applied in the standard magnetic inversion scheme to mitigate the remanence effects, especially in the case of varying remanence directions. In this paper, NSS data were employed along with gravity data for three-dimensional cross-gradient joint inversion, which can significantly reduce the remanence effects and enhance the reliability of both density and magnetization models. Meanwhile, depth-weightings and bound constraints were also incorporated in this joint algorithm to improve the inversion quality. Synthetic and field examples show that the proposed combination of cross-gradient constraints and the NSS transform produce better results in terms of the data resolution, compatibility, and reliability than that of separate inversions and that of joint inversions with the total magnetization intensity (TMI) data. Thus, this method was found to be very useful and is recommended for applications in the presence of strong remanent magnetization.
Puig, Marta; Castellano, David; Pantano, Lorena; Giner-Delgado, Carla; Izquierdo, David; Gayà-Vidal, Magdalena; Lucas-Lledó, José Ignacio; Esko, Tõnu; Terao, Chikashi; Matsuda, Fumihiko; Cáceres, Mario
2015-01-01
Despite many years of study into inversions, very little is known about their functional consequences, especially in humans. A common hypothesis is that the selective value of inversions stems in part from their effects on nearby genes, although evidence of this in natural populations is almost nonexistent. Here we present a global analysis of a new 415-kb polymorphic inversion that is among the longest ones found in humans and is the first with clear position effects. This inversion is located in chromosome 19 and has been generated by non-homologous end joining between blocks of transposable elements with low identity. PCR genotyping in 541 individuals from eight different human populations allowed the detection of tag SNPs and inversion genotyping in multiple populations worldwide, showing that the inverted allele is mainly found in East Asia with an average frequency of 4.7%. Interestingly, one of the breakpoints disrupts the transcription factor gene ZNF257, causing a significant reduction in the total expression level of this gene in lymphoblastoid cell lines. RNA-Seq analysis of the effects of this expression change in standard homozygotes and inversion heterozygotes revealed distinct expression patterns that were validated by quantitative RT-PCR. Moreover, we have found a new fusion transcript that is generated exclusively from inverted chromosomes around one of the breakpoints. Finally, by the analysis of the associated nucleotide variation, we have estimated that the inversion was generated ~40,000–50,000 years ago and, while a neutral evolution cannot be ruled out, its current frequencies are more consistent with those expected for a deleterious variant, although no significant association with phenotypic traits has been found so far. PMID:26427027
Puig, Marta; Castellano, David; Pantano, Lorena; Giner-Delgado, Carla; Izquierdo, David; Gayà-Vidal, Magdalena; Lucas-Lledó, José Ignacio; Esko, Tõnu; Terao, Chikashi; Matsuda, Fumihiko; Cáceres, Mario
2015-10-01
Despite many years of study into inversions, very little is known about their functional consequences, especially in humans. A common hypothesis is that the selective value of inversions stems in part from their effects on nearby genes, although evidence of this in natural populations is almost nonexistent. Here we present a global analysis of a new 415-kb polymorphic inversion that is among the longest ones found in humans and is the first with clear position effects. This inversion is located in chromosome 19 and has been generated by non-homologous end joining between blocks of transposable elements with low identity. PCR genotyping in 541 individuals from eight different human populations allowed the detection of tag SNPs and inversion genotyping in multiple populations worldwide, showing that the inverted allele is mainly found in East Asia with an average frequency of 4.7%. Interestingly, one of the breakpoints disrupts the transcription factor gene ZNF257, causing a significant reduction in the total expression level of this gene in lymphoblastoid cell lines. RNA-Seq analysis of the effects of this expression change in standard homozygotes and inversion heterozygotes revealed distinct expression patterns that were validated by quantitative RT-PCR. Moreover, we have found a new fusion transcript that is generated exclusively from inverted chromosomes around one of the breakpoints. Finally, by the analysis of the associated nucleotide variation, we have estimated that the inversion was generated ~40,000-50,000 years ago and, while a neutral evolution cannot be ruled out, its current frequencies are more consistent with those expected for a deleterious variant, although no significant association with phenotypic traits has been found so far.
Carnaghi, Andrea; Mitrovic, Aleksandra; Leder, Helmut; Fantoni, Carlo; Silani, Giorgia
2018-01-01
A controversial hypothesis, named the Sexualized Body Inversion Hypothesis (SBIH), claims similar visual processing of sexually objectified women (i.e., with a focus on the sexual body parts) and inanimate objects as indicated by an absence of the inversion effect for both type of stimuli. The current study aims at shedding light into the mechanisms behind the SBIH in a series of 4 experiments. Using a modified version of Bernard et al.´s (2012) visual-matching task, first we tested the core assumption of the SBIH, namely that a similar processing style occurs for sexualized human bodies and objects. In Experiments 1 and 2 a non-sexualized (personalized) condition plus two object-control conditions (mannequins, and houses) were included in the experimental design. Results showed an inversion effect for images of personalized women and mannequins, but not for sexualized women and houses. Second, we explored whether this effect was driven by differences in stimulus asymmetry, by testing the mediating and moderating role of this visual feature. In Experiment 3, we provided the first evidence that not only the sexual attributes of the images but also additional perceptual features of the stimuli, such as their asymmetry, played a moderating role in shaping the inversion effect. Lastly, we investigated the strategy adopted in the visual-matching task by tracking eye movements of the participants. Results of Experiment 4 suggest an association between a specific pattern of visual exploration of the images and the presence of the inversion effect. Findings are discussed with respect to the literature on sexual objectification. PMID:29621249
Vojtkó, András; Farkas, Tünde; Szabó, Anna; Havadtői, Krisztina; Vojtkó, Anna E.; Tölgyesi, Csaba; Cseh, Viktória; Erdős, László; Maák, István Elek; Keppel, Gunnar
2017-01-01
Background and aims Dolines are small- to large-sized bowl-shaped depressions of karst surfaces. They may constitute important microrefugia, as thermal inversion often maintains cooler conditions within them. This study aimed to identify the effects of large- (macroclimate) and small-scale (slope aspect and vegetation type) environmental factors on cool-adapted plants in karst dolines of East-Central Europe. We also evaluated the potential of these dolines to be microrefugia that mitigate the effects of climate change on cool-adapted plants in both forest and grassland ecosystems. Methods We compared surveys of plant species composition that were made between 2007 and 2015 in 21 dolines distributed across four mountain ranges (sites) in Hungary and Romania. We examined the effects of environmental factors on the distribution and number of cool-adapted plants on three scales: (1) regional (all sites); (2) within sites and; (3) within dolines. Generalized linear models and non-parametric tests were used for the analyses. Key Results Macroclimate, vegetation type and aspect were all significant predictors of the diversity of cool-adapted plants. More cool-adapted plants were recorded in the coolest site, with only few found in the warmest site. At the warmest site, the distribution of cool-adapted plants was restricted to the deepest parts of dolines. Within sites of intermediate temperature and humidity, the effect of vegetation type and aspect on the diversity of cool-adapted plants was often significant, with more taxa being found in grasslands (versus forests) and on north-facing slopes (versus south-facing slopes). Conclusions There is large variation in the number and spatial distribution of cool-adapted plants in karst dolines, which is related to large- and small-scale environmental factors. Both macro- and microrefugia are therefore likely to play important roles in facilitating the persistence of cool-adapted plants under global warming. PMID:28025290
Lee, Meei-Shyuan; Huang, Yi-Chen; Wahlqvist, Mark L; Wu, Tsai-Yi; Chou, Yu-Ching; Wu, Mei-Hsuan; Yu, Jyh-Cherng; Sun, Chien-An
2011-01-01
Background Evidence for an association between vitamin D status and breast cancer is now more convincing, but is uncertain in subtropical areas like Taiwan. This hospital-based case-control study examined the relationship of breast cancer with vitamin D intake and sunlight exposure. Methods A total of 200 incident breast cancer cases in a Taipei hospital were matched with 200 controls by date of interview and menopausal status. Information on risk factors for breast cancer was collected in face-to-face interviews and assessed with reference to vitamin D intake (foods and nutrients) and sunlight exposure. Vitamin D intake was divided into quartiles, and threshold effect was evaluated by comparing Q2–Q4 with Q1. Results After controlling for age, education, parity, hormone replacement therapy, body mass index (BMI), energy intake, menopausal status, and daily sunlight exposure, the risk of breast cancer in participants with a dietary vitamin D intake greater than 5 µg per day was significantly lower (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.24–0.97) than that of participants with an intake less than 2 µg per day. In analysis stratified by menopausal status and BMI, both dietary vitamin D and total vitamin D intakes were associated with a protective effect among premenopausal women. There was a significant linear trend for breast cancer risk and dietary vitamin D intake in premenopausal women (P = 0.02). In participants with a BMI lower than 24 kg/m2 (ie, normal weight), dietary vitamin D intake was inversely related to breast cancer risk (P for trend = 0.002), and a threshold effect was apparent (Q2–Q4 vs Q1: OR, 0.46; 95% CI, 0.23–0.90). Conclusions Vitamin D had a protective effect against breast cancer in premenopausal women of normal weight in subtropical Taiwan, especially an intake greater than 5 µg per day. PMID:21160130
Bátori, Zoltán; Vojtkó, András; Farkas, Tünde; Szabó, Anna; Havadtői, Krisztina; Vojtkó, Anna E; Tölgyesi, Csaba; Cseh, Viktória; Erdős, László; Maák, István Elek; Keppel, Gunnar
2017-01-01
Dolines are small- to large-sized bowl-shaped depressions of karst surfaces. They may constitute important microrefugia, as thermal inversion often maintains cooler conditions within them. This study aimed to identify the effects of large- (macroclimate) and small-scale (slope aspect and vegetation type) environmental factors on cool-adapted plants in karst dolines of East-Central Europe. We also evaluated the potential of these dolines to be microrefugia that mitigate the effects of climate change on cool-adapted plants in both forest and grassland ecosystems. We compared surveys of plant species composition that were made between 2007 and 2015 in 21 dolines distributed across four mountain ranges (sites) in Hungary and Romania. We examined the effects of environmental factors on the distribution and number of cool-adapted plants on three scales: (1) regional (all sites); (2) within sites and; (3) within dolines. Generalized linear models and non-parametric tests were used for the analyses. Macroclimate, vegetation type and aspect were all significant predictors of the diversity of cool-adapted plants. More cool-adapted plants were recorded in the coolest site, with only few found in the warmest site. At the warmest site, the distribution of cool-adapted plants was restricted to the deepest parts of dolines. Within sites of intermediate temperature and humidity, the effect of vegetation type and aspect on the diversity of cool-adapted plants was often significant, with more taxa being found in grasslands (versus forests) and on north-facing slopes (versus south-facing slopes). There is large variation in the number and spatial distribution of cool-adapted plants in karst dolines, which is related to large- and small-scale environmental factors. Both macro- and microrefugia are therefore likely to play important roles in facilitating the persistence of cool-adapted plants under global warming. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Effects of shoot inversion on stem structure in Pharbitis nil
NASA Technical Reports Server (NTRS)
Prasad, T. K.; Sack, F. D.; Cline, M. G.
1988-01-01
The effects of shoot inversion on stem structure over 72 hr were investigated in Pharbitis nil by analyzing cell number, cell length, and the cross sectional areas of cells, tissues, and regions. An increase in stem diameter can be attributed to an increase in both cell number and cross sectional area of pith (primarily) and vascular tissue (secondarily). Qualitative observations of cell wall thickness in the light microscope did not reveal any significant effects of shoot inversion on this parameter. The inhibition of shoot elongation was accompanied by a significant decrease in cell length in the pith. The results are generally consistent with an ethylene effect on cell dimensions, especially in the pith.
Inverse spin Hall and spin rectification effects in NiFe/FeMn exchange-biased thin films
NASA Astrophysics Data System (ADS)
Garcia, W. J. S.; Seeger, R. L.; da Silva, R. B.; Harres, A.
2017-11-01
Materials presenting high spin-orbit coupling are able to convert spin currents in charge currents. The phenomenon, known as inverse spin Hall effect, promises to revolutionize spintronic technology enabling the electrical detection of spin currents. It has been observed in a variety of systems, usually non-magnetic metals. We study the voltage emerging in exchange biased Ta/NiFe/FeMn/Ta thin films near the ferromagnetic resonance. Measured signals are related to both inverse spin Hall and spin rectification effects, and two distinct protocols were employed to separate their contributions.The curve shift due to the exchange bias effect may enable high frequency applications without an external applied magnetic field.
Combat Experience and Mental Health in the Israel National Health Survey.
Lubin, Gadi; Barash, Igor; Levinson, Daphna
2016-01-01
To compare the mental health status of those who participated in combat related activities during their service with that of soldiers whose army service did not include combat related activities Method: A representative sample extracted from the National Population Register of non-institutionalized residents aged 21 or older of Israel was used in this crosssectional survey. Data on mental health disorders, sociodemographic background and army service were collected using face-to-face computer-assisted interviews. Combat experience per se was not associated with lifetime diagnosis of PTSD. Former combat soldiers had significantly lower lifetime prevalence and 12 months prevalence of any mood or anxiety disorders including PTSD. This work is in line with previous literature showing that combat exposure, as such, has limited contribution to lifetime PTSD in some groups of veterans. The inverse relationship between combat exposure and PTSD might be explained by the selection of potential combatants among all recruits and by the heightened preparedness to military life stressors.
NASA Astrophysics Data System (ADS)
Braiek, A.; Adili, A.; Albouchi, F.; Karkri, M.; Ben Nasrallah, S.
2016-06-01
The aim of this work is to simultaneously identify the conductive and radiative parameters of a semitransparent sample using a photothermal method associated with an inverse problem. The identification of the conductive and radiative proprieties is performed by the minimization of an objective function that represents the errors between calculated temperature and measured signal. The calculated temperature is obtained from a theoretical model built with the thermal quadrupole formalism. Measurement is obtained in the rear face of the sample whose front face is excited by a crenel of heat flux. For identification procedure, a genetic algorithm is developed and used. The genetic algorithm is a useful tool in the simultaneous estimation of correlated or nearly correlated parameters, which can be a limiting factor for the gradient-based methods. The results of the identification procedure show the efficiency and the stability of the genetic algorithm to simultaneously estimate the conductive and radiative properties of clear glass.
Abbas, Ozan Luay; Kurkcuoglu, Ayla; Aytop, Cigdem Derya; Uysal, Cengiz; Pelin, Can
2017-10-01
Visual perception of symmetry is a major determinant of satisfaction after aesthetic rhinoplasty. In this study, we sought to investigate the existence of any relationship between anthropometric characteristics of the face and visual perceptions of asymmetry among rhinoplasty patients and to evaluate tools that can shed light on patients who appear at high risk for exaggerating potential asymmetries. In the first part, 168 rhinoplasty patients were asked to fill out the demographic questionnaire, nasal shape evaluation scale, and the somatosensory amplification scale. In the second part, we examined the relationship between anthropometric characteristics of the face and visual perceptions of asymmetry using standardized photographs of 100 medical students. In the third part, patients answered the rhinoplasty outcome evaluation questionnaire 6 months after the surgery. Objectively, no symmetrical face was observed in the anthropometric evaluation. Subjectively, only 73% and 54% of the faces were considered asymmetrical by the rhinoplasty and the control groups, respectively. The rate of asymmetry perception was significantly greater in revision patients when compared with primary rhinoplasty patients. The relationship between the rate of subjective perception of asymmetry and the somatosensory amplification scale scores was statistically significant. We found a significant inverse relationship between the rate of asymmetry perception and the rhinoplasty outcome evaluation scores. Plastic surgeons should be aware of this high selectivity in asymmetry perception, which is associated with poor postoperative satisfaction. Somatosensory amplification scale may help identify rhinoplasty patients at a high risk for exaggerating potential asymmetries. III.
Acoustic and elastic waveform inversion best practices
NASA Astrophysics Data System (ADS)
Modrak, Ryan T.
Reaching the global minimum of a waveform misfit function requires careful choices about the nonlinear optimization, preconditioning and regularization methods underlying an inversion. Because waveform inversion problems are susceptible to erratic convergence, one or two test cases are not enough to reliably inform such decisions. We identify best practices instead using two global, one regional and four near-surface acoustic test problems. To obtain meaningful quantitative comparisons, we carry out hundreds acoustic inversions, varying one aspect of the implementation at a time. Comparing nonlinear optimization algorithms, we find that L-BFGS provides computational savings over nonlinear conjugate gradient methods in a wide variety of test cases. Comparing preconditioners, we show that a new diagonal scaling derived from the adjoint of the forward operator provides better performance than two conventional preconditioning schemes. Comparing regularization strategies, we find that projection, convolution, Tikhonov regularization, and total variation regularization are effective in different contexts. Besides these issues, reliability and efficiency in waveform inversion depend on close numerical attention and care. Implementation details have a strong effect on computational cost, regardless of the chosen material parameterization or nonlinear optimization algorithm. Building on the acoustic inversion results, we carry out elastic experiments with four test problems, three objective functions, and four material parameterizations. The choice of parameterization for isotropic elastic media is found to be more complicated than previous studies suggests, with "wavespeed-like'' parameters performing well with phase-based objective functions and Lame parameters performing well with amplitude-based objective functions. Reliability and efficiency can be even harder to achieve in transversely isotropic elastic inversions because rotation angle parameters describing fast-axis direction are difficult to recover. Using Voigt or Chen-Tromp parameters avoids the need to include rotation angles explicitly and provides an effective strategy for anisotropic inversion. The need for flexible and portable workflow management tools for seismic inversion also poses a major challenge. In a final chapter, the software used to the carry out the above experiments is described and instructions for reproducing experimental results are given.
Artificial masculinization in tilapia involves androgen receptor activation.
Golan, Matan; Levavi-Sivan, Berta
2014-10-01
Estrogens have a pivotal role in natural female sexual differentiation of tilapia while lack of steroids results in testicular development. Despite the fact that androgens do not participate in natural sex differentiation, synthetic androgens, mainly 17-α-methyltestosterone (MT) are effective in the production of all-male fish in aquaculture. The sex inversion potency of synthetic androgens may arise from their androgenic activity or else as inhibitors of aromatase activity. The current study is an attempt to differentiate between the two alleged activities in order to evaluate their contribution to the sex inversion process and aid the search for novel sex inversion agents. In the present study, MT inhibited aromatase activity, when applied in vitro as did the non-aromatizable androgen dihydrotestosterone (DHT). In comparison, exposure to fadrozole, a specific aromatase inhibitor, was considerably more effective. Androgenic activity of MT was evaluated by exposure of Sciaenochromis fryeri fry to the substance and testing for the appearance of blue color. Flutamide, an androgen antagonist, administered concomitantly with MT, reduced the appearance of the blue color and the sex inversion potency of MT in a dose-dependent manner. In tilapia, administration of MT, fadrozole or DHT resulted in efficient sex inversion while flutamide reduced the sex inversion potency of all three compounds. In the case of MT and DHT the decrease in sex inversion efficiency caused by flutamide is most likely due to the direct blocking of the androgen binding to its cognate receptor. The negative effect of flutamide on the efficiency of the fadrozole treatment may indicate that the masculinizing activity of fadrozole may be attributed to excess, un-aromatized, androgens accumulated in the differentiating gonad. The present study shows that when androgen receptors are blocked, there is a reduction in the efficiency of sex inversion treatments. Our results suggest that in contrast to natural sex differentiation, during sex inversion treatments, androgens, either endogenous or exogenous, participate in inducing testicular differentiation. Copyright © 2014 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Hsia, T. C.; Lu, G. Z.; Han, W. H.
1987-01-01
In advanced robot control problems, on-line computation of inverse Jacobian solution is frequently required. Parallel processing architecture is an effective way to reduce computation time. A parallel processing architecture is developed for the inverse Jacobian (inverse differential kinematic equation) of the PUMA arm. The proposed pipeline/parallel algorithm can be inplemented on an IC chip using systolic linear arrays. This implementation requires 27 processing cells and 25 time units. Computation time is thus significantly reduced.
The effect of face eccentricity on the perception of gaze direction.
Todorović, Dejan
2009-01-01
The perception of a looker's gaze direction depends not only on iris eccentricity (the position of the looker's irises within the sclera) but also on the orientation of the lookers' head. One among several potential cues of head orientation is face eccentricity, the position of the inner features of the face (eyes, nose, mouth) within the head contour, as viewed by the observer. For natural faces this cue is confounded with many other head-orientation cues, but in schematic faces it can be studied in isolation. Salient novel illustrations of the effectiveness of face eccentricity are 'Necker faces', which involve equal iris eccentricities but multiple perceived gaze directions. In four experiments, iris and face eccentricity in schematic faces were manipulated, revealing strong and consistent effects of face eccentricity on perceived gaze direction, with different types of tasks. An additional experiment confirmed the 'Mona Lisa' effect with this type of stimuli. Face eccentricity most likely acted as a simple but robust cue of head turn. A simple computational account of combined effects of cues of eye and head turn on perceived gaze direction is presented, including a formal condition for the perception of direct gaze. An account of the 'Mona Lisa' effect is presented.
Hatadani, Luciane Mendes; Klaczko, Louis Bernard
2008-07-01
The second chromosome of Drosophila mediopunctata is highly polymorphic for inversions. Previous work reported a significant interaction between these inversions and collecting date on wing size, suggesting the presence of genotype-environment interaction. We performed experiments in the laboratory to test for the joint effects of temperature and chromosome inversions on size and shape of the wing in D. mediopunctata. Size was measured as the centroid size, and shape was analyzed using the generalized least squares Procrustes superimposition followed by discriminant analysis and canonical variates analysis of partial warps and uniform components scores. Our findings show that wing size and shape are influenced by temperature, sex, and karyotype. We also found evidence suggestive of an interaction between the effects of karyotype and temperature on wing shape, indicating the existence of genotype-environment interaction for this trait in D. mediopunctata. In addition, the association between wing size and chromosome inversions is in agreement with previous results indicating that these inversions might be accumulating alleles adapted to different temperatures. However, no significant interaction between temperature and karyotype for size was found--in spite of the significant presence of temperature-genotype (cross) interaction. We suggest that other ecological factors--such as larval crowding--or seasonal variation of genetic content within inversions may explain the previous results.
Regional brain responses in nulliparous women to emotional infant stimuli.
Montoya, Jessica L; Landi, Nicole; Kober, Hedy; Worhunsky, Patrick D; Rutherford, Helena J V; Mencl, W Einar; Mayes, Linda C; Potenza, Marc N
2012-01-01
Infant cries and facial expressions influence social interactions and elicit caretaking behaviors from adults. Recent neuroimaging studies suggest that neural responses to infant stimuli involve brain regions that process rewards. However, these studies have yet to investigate individual differences in tendencies to engage or withdraw from motivationally relevant stimuli. To investigate this, we used event-related fMRI to scan 17 nulliparous women. Participants were presented with novel infant cries of two distress levels (low and high) and unknown infant faces of varying affect (happy, sad, and neutral) in a randomized, counter-balanced order. Brain activation was subsequently correlated with scores on the Behavioral Inhibition System/Behavioral Activation System scale. Infant cries activated bilateral superior and middle temporal gyri (STG and MTG) and precentral and postcentral gyri. Activation was greater in bilateral temporal cortices for low- relative to high-distress cries. Happy relative to neutral faces activated the ventral striatum, caudate, ventromedial prefrontal, and orbitofrontal cortices. Sad versus neutral faces activated the precuneus, cuneus, and posterior cingulate cortex, and behavioral activation drive correlated with occipital cortical activations in this contrast. Behavioral inhibition correlated with activation in the right STG for high- and low-distress cries relative to pink noise. Behavioral drive correlated inversely with putamen, caudate, and thalamic activations for the comparison of high-distress cries to pink noise. Reward-responsiveness correlated with activation in the left precentral gyrus during the perception of low-distress cries relative to pink noise. Our findings indicate that infant cry stimuli elicit activations in areas implicated in auditory processing and social cognition. Happy infant faces may be encoded as rewarding, whereas sad faces activate regions associated with empathic processing. Differences in motivational tendencies may modulate neural responses to infant cues.
NASA Technical Reports Server (NTRS)
Liu, Yen; Vinokur, Marcel; Wang, Z. J.
2004-01-01
A three-dimensional, high-order, conservative, and efficient discontinuous spectral volume (SV) method for the solutions of Maxwell's equations on unstructured grids is presented. The concept of discontinuous 2nd high-order loca1 representations to achieve conservation and high accuracy is utilized in a manner similar to the Discontinuous Galerkin (DG) method, but instead of using a Galerkin finite-element formulation, the SV method is based on a finite-volume approach to attain a simpler formulation. Conventional unstructured finite-volume methods require data reconstruction based on the least-squares formulation using neighboring cell data. Since each unknown employs a different stencil, one must repeat the least-squares inversion for every cell at each time step, or to store the inversion coefficients. In a high-order, three-dimensional computation, the former would involve impractically large CPU time, while for the latter the memory requirement becomes prohibitive. In the SV method, one starts with a relatively coarse grid of triangles or tetrahedra, called spectral volumes (SVs), and partition each SV into a number of structured subcells, called control volumes (CVs), that support a polynomial expansion of a desired degree of precision. The unknowns are cell averages over CVs. If all the SVs are partitioned in a geometrically similar manner, the reconstruction becomes universal as a weighted sum of unknowns, and only a few universal coefficients need to be stored for the surface integrals over CV faces. Since the solution is discontinuous across the SV boundaries, a Riemann solver is thus necessary to maintain conservation. In the paper, multi-parameter and symmetric SV partitions, up to quartic for triangle and cubic for tetrahedron, are first presented. The corresponding weight coefficients for CV face integrals in terms of CV cell averages for each partition are analytically determined. These discretization formulas are then applied to the integral form of the Maxwell equations. All numerical procedures for outer boundary, material interface, zonal interface, and interior SV face are unified with a single characteristic formulation. The load balancing in a massive parallel computing environment is therefore easier to achieve. A parameter is introduced in the Riemann solver to control the strength of the smoothing term. Important aspects of the data structure and its effects to communication and the optimum use of cache memory are discussed. Results will be presented for plane TE and TM waves incident on a perfectly conducting cylinder for up to fifth order of accuracy, and a plane wave incident on a perfectly conducting sphere for up to fourth order of accuracy. Comparisons are made with exact solutions for these cases.
Jin, Zi-Yi; Wu, Ming; Han, Ren-Qiang; Zhang, Xiao-Feng; Wang, Xu-Shan; Liu, Ai-Ming; Zhou, Jin-Yi; Lu, Qing-Yi; Zhang, Zuo-Feng; Zhao, Jin-Kou
2013-01-01
Protective effect of garlic on the development of cancer has been reported in vitro and in vivo experimental studies, however, few human epidemiological studies have evaluated the relationship. A population-based case-control study has been conducted in a Chinese population from 2003 to 2010, with the aim to explore the association between raw garlic consumption and lung cancer. Epidemiological data were collected by face-to-face interviews using a standard questionnaire among 1,424 lung cancer cases and 4,543 healthy controls. Unconditional logistic regression was employed to estimate adjusted odds ratios (OR) and their 95% confidence intervals (CIs), and to evaluate ratio of odds ratios (ROR) for multiplicative interactions between raw garlic consumption and other risk factors. After adjusting for potential confounding factors, raw garlic consumption of ≥ 2 times per week is inversely associated with lung cancer (OR = 0.56, 95% CI = 0.44-0.72) with a monotonic dose-response relationship (p for trend <0.001). Furthermore, strong interactions at either additive and/or multiplicative scales were observed between raw garlic consumption and tobacco smoking (Synergy Index (SI) = 0.70, 95% CI = 0.57-0.85; and ROR = 0.78, 95% CI = 0.67-0.90), as well as high-temperature cooking oil fume (ROR = 0.77, 95% CI = 0.59-1.00). In conclusion, protective association between intake of raw garlic and lung cancer has been observed with a dose-response pattern, suggesting that garlic may potentially serve as a chemopreventive agent for lung cancer. Effective components in garlic in lung cancer chemoprevention warrant further in-depth investigation. PMID:23658367
Viewpoint invariance in the discrimination of upright and inverted faces
Wright, Alissa; Barton, Jason JS
2008-01-01
Current models of face processing support an orientation-dependent expert face processing mechanism. However, even when upright, faces are encountered from different viewpoints, across which a face processing system must be able to generalize. Different computational models have generated competing predictions of how viewpoint variation might affect the perception of upright versus inverted faces. Our goal was to examine the interaction between viewpoint variation and orientation on face discrimination. Sixteen normal subjects performed an oddity-paradigm requiring subjects to discriminate changes in three simultaneously viewed morphed faces presented either upright or inverted. In one type of trial all the faces were seen in frontal view, in the other all faces varied in viewpoint, rotated 45° from each other. After the effects of orientation were adjusted for perceptual difficulty, there were only main effects of orientation and viewpoint, with no interaction between orientation and viewpoint. We conclude that the effects of viewpoint variation on the perceptual discrimination of faces is not different for upright versus inverted faces, indicating that its effects are independent of the expertise that exists for upright faces. PMID:18804486
Recognition of own-race and other-race faces by three-month-old infants.
Sangrigoli, Sandy; De Schonen, Scania
2004-10-01
People are better at recognizing faces of their own race than faces of another race. Such race specificity may be due to differential expertise in the two races. In order to find out whether this other-race effect develops as early as face-recognition skills or whether it is a long-term effect of acquired expertise, we tested face recognition in 3-month-old Caucasian infants by conducting two experiments using Caucasian and Asiatic faces and a visual pair-comparison task. We hypothesized that if the other race effect develops together with face processing skills during the first months of life, the ability to recognize own-race faces will be greater than the ability to recognize other-race faces: 3-month-old Caucasian infants should be better at recognizing Caucasian faces than Asiatic faces. If, on the contrary, the other-race effect is the long-term result of acquired expertise, no difference between recognizing own- and other-race faces will be observed at that age. In Experiment 1, Caucasian infants were habituated to a single face. Recognition was assessed by a novelty preference paradigm. The infants' recognition performance was better for Caucasian than for Asiatic faces. In Experiment 2, Caucasian infants were familiarized with three individual faces. Recognition was demonstrated with both Caucasian and Asiatic faces. These results suggest that (i) the representation of face information by 3-month-olds may be race-experience-dependent (Experiment 1), and (ii) short-term familiarization with exemplars of another race group is sufficient to reduce the other-race effect and to extend the power of face processing (Experiment 2).
Approximation of reliabilities for multiple-trait model with maternal effects.
Strabel, T; Misztal, I; Bertrand, J K
2001-04-01
Reliabilities for a multiple-trait maternal model were obtained by combining reliabilities obtained from single-trait models. Single-trait reliabilities were obtained using an approximation that supported models with additive and permanent environmental effects. For the direct effect, the maternal and permanent environmental variances were assigned to the residual. For the maternal effect, variance of the direct effect was assigned to the residual. Data included 10,550 birth weight, 11,819 weaning weight, and 3,617 postweaning gain records of Senepol cattle. Reliabilities were obtained by generalized inversion and by using single-trait and multiple-trait approximation methods. Some reliabilities obtained by inversion were negative because inbreeding was ignored in calculating the inverse of the relationship matrix. The multiple-trait approximation method reduced the bias of approximation when compared with the single-trait method. The correlations between reliabilities obtained by inversion and by multiple-trait procedures for the direct effect were 0.85 for birth weight, 0.94 for weaning weight, and 0.96 for postweaning gain. Correlations for maternal effects for birth weight and weaning weight were 0.96 to 0.98 for both approximations. Further improvements can be achieved by refining the single-trait procedures.
Wanitphakdeedecha, Rungsima; Ungaksornpairote, Chanida; Kaewkes, Arisa; Rojanavanich, Viboon; Phothong, Weeranut; Manuskiatti, Woraphong
2016-12-01
Botulinum toxin type A (BTA) has been approved for the treatment of strabismus, blepharospasm, muscle spasm, cervical dystonia, pain syndrome, glabella wrinkles, and severe primary axillary hyperhidrosis. Intradermal injection of BTA has been used off-label by many clinicians for the purpose of face-lifting effect. Few studies on onabotulinumtoxinA (ONA) demonstrated no clinical efficacy on face-lifting effect when comparing to normal saline solution (NSS). So far, there is no split-face comparison study on face-lifting effect of abobotulinumtoxinA (ABO). To determine the face-lifting effect of ABO intradermal injection and NSS. Twenty-two subjects with symmetrical faces on both facial expression and expressionless were randomly injected with ABO at 1:7 cc dilution (500 unit or one vial in 7 cc of NSS) on one side and NSS on the other side using intradermal injection technique. Standardized photographic documentation was obtained at baseline, and at 2 weeks after treatment. The face-lifting effect was graded by two blinded dermatologists using photographic comparison and rated by the patients. Side effects were also recorded at the end of the study. Face-lifting effect was demonstrated in 40.9% and 4.5% of patients with ABO and NSS, respectively. There was a statistically significant difference in face-lifting effect when comparing between ABO and NSS (P = 0.021). The face-lifting was reported in 50.0% of patients receiving ABO injection. The patients with oval-face shape tended to respond better with ABO (P = 0.046). The odd of face-lifting effect for patients aged younger than 32 was higher than patients aged older than 32 with the odds ratio of 7.9 and 95% confidence interval of 1.1-56.1. Facial asymmetry was found in 22.7% of subjects. This study demonstrated the face-lifting effect of ABO intradermal injection. Patients with oval-face shape and aged younger than 32 tended to respond better. Therefore, patient selection should be emphasized to improve efficacy of this technique. © 2016 The Authors. Journal of Cosmetic Dermatology Published by Wiley Periodicals, Inc.
Global shape information increases but color information decreases the composite face effect.
Retter, Talia L; Rossion, Bruno
2015-01-01
The separation of visual shape and surface information may be useful for understanding holistic face perception--that is, the perception of a face as a single unit (Jiang, Blanz, & Rossion, 2011, Visual Cognition, 19, 1003-1034). A widely used measure of holistic face perception is the composite face effect (CFE), in which identical top face halves appear different when aligned with bottom face halves from different identities. In the present study the influences of global face shape (ie contour of the face) and color information on the CFE are investigated, with the hypothesis that global face shape supports but color impairs holistic face perception as measured in this paradigm. In experiment 1 the CFE is significantly increased when face stimuli possess natural global shape information than when cropped to a generic (ie oval) global shape; this effect is not found when the stimuli are presented inverted. In experiment 2 the CFE is significantly decreased when face stimuli are presented with color information than when presented in grayscale. These findings indicate that grayscale stimuli maintaining natural global face shape information provide the most adept measure of holistic face perception in the behavioral composite face paradigm. More generally, they show that reducing different types of information diagnostic for individual face perception can have opposite effects on the CFE, illustrating the functional dissociation between shape and surface information in face perception.
Measuring soil moisture with imaging radars
NASA Technical Reports Server (NTRS)
Dubois, Pascale C.; Vanzyl, Jakob; Engman, Ted
1995-01-01
An empirical model was developed to infer soil moisture and surface roughness from radar data. The accuracy of the inversion technique is assessed by comparing soil moisture obtained with the inversion technique to in situ measurements. The effect of vegetation on the inversion is studied and a method to eliminate the areas where vegetation impairs the algorithm is described.
Vapor Pressure of Antimony Triiodide
2017-12-07
function of inverse temperature ........................................................................................... 4 Fig. 3 Effective ∆Hvapor of...pressure on inverse -temperature with the slope of (∆Hvapor/R). One method of experimentally determining ∆Hvapor, therefore, is to measure the...equilibrium vapor pressure of any material as a function of inverse -temperature where the slope of the data can be used to directly determine ∆Hvapor
Dustfall Effect on Hyperspectral Inversion of Chlorophyll Content - a Laboratory Experiment
NASA Astrophysics Data System (ADS)
Chen, Yuteng; Ma, Baodong; Li, Xuexin; Zhang, Song; Wu, Lixin
2018-04-01
Dust pollution is serious in many areas of China. It is of great significance to estimate chlorophyll content of vegetation accurately by hyperspectral remote sensing for assessing the vegetation growth status and monitoring the ecological environment in dusty areas. By using selected vegetation indices including Medium Resolution Imaging Spectrometer Terrestrial Chlorophyll Index (MTCI) Double Difference Index (DD) and Red Edge Position Index (REP), chlorophyll inversion models were built to study the accuracy of hyperspectral inversion of chlorophyll content based on a laboratory experiment. The results show that: (1) REP exponential model has the most stable accuracy for inversion of chlorophyll content in dusty environment. When dustfall amount is less than 80 g/m2, the inversion accuracy based on REP is stable with the variation of dustfall amount. When dustfall amount is greater than 80 g/m2, the inversion accuracy is slightly fluctuation. (2) Inversion accuracy of DD is worst among three models. (3) MTCI logarithm model has high inversion accuracy when dustfall amount is less than 80 g/m2; When dustfall amount is greater than 80 g/m2, inversion accuracy decreases regularly and inversion accuracy of modified MTCI (mMTCI) increases significantly. The results provide experimental basis and theoretical reference for hyperspectral remote sensing inversion of chlorophyll content.
Weighting by Inverse Variance or by Sample Size in Random-Effects Meta-Analysis
ERIC Educational Resources Information Center
Marin-Martinez, Fulgencio; Sanchez-Meca, Julio
2010-01-01
Most of the statistical procedures in meta-analysis are based on the estimation of average effect sizes from a set of primary studies. The optimal weight for averaging a set of independent effect sizes is the inverse variance of each effect size, but in practice these weights have to be estimated, being affected by sampling error. When assuming a…
Mapping nonlinear shallow-water tides: a look at the past and future
NASA Astrophysics Data System (ADS)
Andersen, Ole B.; Egbert, Gary D.; Erofeeva, Svetlana Y.; Ray, Richard D.
2006-12-01
Overtides and compound tides are generated by nonlinear mechanisms operative primarily in shallow waters. Their presence complicates tidal analysis owing to the multitude of new constituents and their possible frequency overlap with astronomical tides. The science of nonlinear tides was greatly advanced by the pioneering researches of Christian Le Provost who employed analytical theory, physical modeling, and numerical modeling in many extensive studies, especially of the tides of the English Channel. Le Provost’s complementary work with satellite altimetry motivates our attempts to merge these two interests. After a brief review, we describe initial steps toward the assimilation of altimetry into models of nonlinear tides via generalized inverse methods. A series of barotropic inverse solutions is computed for the M_4 tide over the northwest European Shelf. Future applications of altimetry to regions with fewer in situ measurements will require improved understanding of error covariance models because these control the tradeoffs between fitting hydrodynamics and data, a delicate issue in coastal regions. While M_4 can now be robustly determined along the Topex/Poseidon satellite ground tracks, many other compound tides face serious aliasing problems.
Growth patterns for shape-shifting elastic bilayers.
van Rees, Wim M; Vouga, Etienne; Mahadevan, L
2017-10-31
Inspired by the differential-growth-driven morphogenesis of leaves, flowers, and other tissues, there is increasing interest in artificial analogs of these shape-shifting thin sheets made of active materials that respond to environmental stimuli such as heat, light, and humidity. But how can we determine the growth patterns to achieve a given shape from another shape? We solve this geometric inverse problem of determining the growth factors and directions (the metric tensors) for a given isotropic elastic bilayer to grow into a target shape by posing and solving an elastic energy minimization problem. A mathematical equivalence between bilayers and curved monolayers simplifies the inverse problem considerably by providing algebraic expressions for the growth metric tensors in terms of those of the final shape. This approach also allows us to prove that we can grow any target surface from any reference surface using orthotropically growing bilayers. We demonstrate this by numerically simulating the growth of a flat sheet into a face, a cylindrical sheet into a flower, and a flat sheet into a complex canyon-like structure.
Growth patterns for shape-shifting elastic bilayers
van Rees, Wim M.; Vouga, Etienne; Mahadevan, L.
2017-01-01
Inspired by the differential-growth-driven morphogenesis of leaves, flowers, and other tissues, there is increasing interest in artificial analogs of these shape-shifting thin sheets made of active materials that respond to environmental stimuli such as heat, light, and humidity. But how can we determine the growth patterns to achieve a given shape from another shape? We solve this geometric inverse problem of determining the growth factors and directions (the metric tensors) for a given isotropic elastic bilayer to grow into a target shape by posing and solving an elastic energy minimization problem. A mathematical equivalence between bilayers and curved monolayers simplifies the inverse problem considerably by providing algebraic expressions for the growth metric tensors in terms of those of the final shape. This approach also allows us to prove that we can grow any target surface from any reference surface using orthotropically growing bilayers. We demonstrate this by numerically simulating the growth of a flat sheet into a face, a cylindrical sheet into a flower, and a flat sheet into a complex canyon-like structure. PMID:29078336
NASA Astrophysics Data System (ADS)
Bragov, A. M.; Balandin, Vl. V.; Kotov, V. L.; Balandin, Vl. Vl.
2018-04-01
We present new experimental results on the investigation of the dynamic properties of sand soil on the basis of the inverse experiment technique using a measuring rod with a flat front-end face. A limited applicability has been shown of the method using the procedure for correcting the shape of the deformation pulse due to dispersion during its propagation in the measuring rod. Estimates of the pulse maximum have been obtained and the results of comparison of numerical calculations with experimental data are given. The sufficient accuracy in determining the drag force during the quasi-stationary stage of penetration has been established. The parameters of dynamic compressibility and resistance to shear of water-saturated sand have been determined in the course of the experimental-theoretical analysis of the maximum values of the drag force and its values at the quasi-stationary stage of penetration. It has been shown that with almost complete water saturation of sand its shear properties are reduced but remain significant in the practically important range of penetration rates.
Investigation of Inversion Polymorphisms in the Human Genome Using Principal Components Analysis
Ma, Jianzhong; Amos, Christopher I.
2012-01-01
Despite the significant advances made over the last few years in mapping inversions with the advent of paired-end sequencing approaches, our understanding of the prevalence and spectrum of inversions in the human genome has lagged behind other types of structural variants, mainly due to the lack of a cost-efficient method applicable to large-scale samples. We propose a novel method based on principal components analysis (PCA) to characterize inversion polymorphisms using high-density SNP genotype data. Our method applies to non-recurrent inversions for which recombination between the inverted and non-inverted segments in inversion heterozygotes is suppressed due to the loss of unbalanced gametes. Inside such an inversion region, an effect similar to population substructure is thus created: two distinct “populations” of inversion homozygotes of different orientations and their 1∶1 admixture, namely the inversion heterozygotes. This kind of substructure can be readily detected by performing PCA locally in the inversion regions. Using simulations, we demonstrated that the proposed method can be used to detect and genotype inversion polymorphisms using unphased genotype data. We applied our method to the phase III HapMap data and inferred the inversion genotypes of known inversion polymorphisms at 8p23.1 and 17q21.31. These inversion genotypes were validated by comparing with literature results and by checking Mendelian consistency using the family data whenever available. Based on the PCA-approach, we also performed a preliminary genome-wide scan for inversions using the HapMap data, which resulted in 2040 candidate inversions, 169 of which overlapped with previously reported inversions. Our method can be readily applied to the abundant SNP data, and is expected to play an important role in developing human genome maps of inversions and exploring associations between inversions and susceptibility of diseases. PMID:22808122
Bukowska, Agnieszka; Sobala, Wojciech; Peplonska, Beata
2015-04-01
The pattern of secretion of many hormones, including prolactin, is dependent on the circadian rhythm. Night shift work involves exposure to artificial light at night and sleep deficiency, which in turn can affect prolactin synthesis. The aim of this study was to evaluate a possible association between night shift work characteristics, sleep quality, lifestyle factors and prolactin concentration, using data from a cross-sectional study of nurses and midwives. A cross-sectional study was conducted among 327 nurses and midwives currently working on rotating night shifts, and 330 nurses and midwives working during the day (aged 40-60 years) (388 premenopausal and 269 postmenopausal). Information about night shift work characteristics, lifestyle, reproductive factors, sleep pattern and other covariates was collected through a face-to-face interview, and from a one-week work and sleep diary completed by the subjects. Weight and height were measured. Prolactin concentration was measured in the morning blood sample using the electrochemiluminesence immunoassay method. Associations were analyzed using linear regression models adjusted for important confounders. Analyses were carried out separately in pre- and postmenopausal women. None of the night shift work or sleep characteristics was significantly associated with prolactin concentration. Prolactin concentration was significantly (p < 0.05) inversely associated with smoking and time of blood sample collection. These results were consistent among both pre- and postmenopausal women. Nulliparity was significantly positively associated with prolactin among premenopausal women, but inversely among postmenopausal. Age was related to prolactin among postmenopausal women only. Our study indicates that rotating night shift work is not associated with prolactin concentration. Smoking, parity, time of blood collection and age among postmenopausal women were significant determinants of prolactin.
Liu, Ping; Zhang, Min; Xie, Xing; Jin, Jie; Holman, C D'Arcy J
2017-03-01
Green tea may have a beneficial role of inhibiting leukemia. Glutathione S-transferases (GSTs) are known to detoxify certain carcinogens. We investigated the roles of green tea consumption and polymorphisms of GSTM1, GSTT1 and GSTP1 on the risk of adult leukemia, and to determine whether the associations varied within GSTs genotypes. A multicenter case-control study was conducted in China, 2008-2013. It comprised 442 incident, hematologically confirmed adult leukemia cases and 442 outpatient controls, individually matched to cases by gender, birth quinquennium and study site. Data were collected by face-to-face interview using a validated questionnaire. Genetic polymorphisms were assayed by PCR. An inverse association between green tea consumption and adult leukemia risk was observed. Compared with non-tea drinkers, the adjusted odds ratios (95 % confidence intervals) were 0.50 (0.27-0.93), 0.31 (0.17-0.55) and 0.53 (0.29-0.99) for those who, respectively, consumed green tea >20 years, ≥2 cups daily and dried tea leaves >1000 g annually. In assessing the associations by GSTs genotypes, risk reduction associated with green tea consumption was stronger in individuals with the GSTT1-null genotype (OR 0.24; 95 % CI 0.11-0.53) than GSTT1-normal carriers (OR 0.67; 95 % CI 0.42-1.05; P interaction = 0.02). GSTM1 and GSTP1 did not significantly modify the inverse association of leukemia with green tea. The results suggest that regular daily green tea consumption may reduce leukemia risk in Chinese adults regardless of GSTM1 and GSTP1 polymorphic status. The association between green tea and adult leukemia risk varied with GSTT1 genotype and highlights further study.
French, Louis M; Lange, Rael T; Marshall, Kathryn; Prokhorenko, Olga; Brickell, Tracey A; Bailie, Jason M; Asmussen, Sarah B; Ivins, Brian; Cooper, Douglas B; Kennedy, Jan E
2014-10-01
Traumatic brain injuries (TBI) sustained in combat frequently co-occur with significant bodily injuries. Intuitively, more extensive bodily injuries might be associated with increased symptom reporting. In 2012, however, French et al. demonstrated an inverse relation between bodily injury severity and symptom reporting. This study expands on that work by examining the influence of location and severity of bodily injuries on symptom reporting after mild TBI. Participants were 579 US military service members who sustained an uncomplicated mild TBI with concurrent bodily injuries and who were evaluated at two military medical centers. Bodily injury severity was quantified using a modified Injury Severity Score (ISSmod). Participants completed the Neurobehavioral Symptom Inventory (NSI) and the Posttraumatic Stress Disorder Checklist (PCL-C), on average, 2.5 months post-injury. There was a significant negative association between ISSmod scores and NSI (r=-0.267, p<0.001) and PCL-C (r=-0.273, p<0.001) total scores. Using linear regression to examine the relation between symptom reporting and injury severity across the six ISS body regions, three body regions were significant predictors of the NSI total score (face; p<0.001; abdomen; p=0.003; extremities; p<0.001) and accounted for 9.3% of the variance (p<0.001). For the PCL-C, two body regions were significant predictors of the PCL-C total score (face; p<0.001; extremities; p<0.001) and accounted for 10.5% of the variance. There was an inverse relation between bodily injury severity and symptom reporting in this sample. Hypothesized explanations include underreporting of symptoms, increased peer support, disruption of fear conditioning because of acute morphine use, or delayed expression of symptoms.
Li, Mengmeng; Dai, Weiwei; Yan, Wei; Liu, Yuanzhen; Wang, Lian; Li, Wei
2017-07-01
We report a case of a 25-year-old Chinese man with an exceptionally prolonged history of pustular psoriasis derived from inverse psoriasis who was unsatisfied with conventional treatment and was successfully treated with a single dose of infliximab without noticeable adverse effects. No recurrence or flaring was observed after 3 months of follow-up. This case illustrates that infliximab may be an effective and safe therapeutic option for patients with refractory pustular psoriasis derived from inverse psoriasis. © 2017 Wiley Periodicals, Inc.
Understanding gender bias in face recognition: effects of divided attention at encoding.
Palmer, Matthew A; Brewer, Neil; Horry, Ruth
2013-03-01
Prior research has demonstrated a female own-gender bias in face recognition, with females better at recognizing female faces than male faces. We explored the basis for this effect by examining the effect of divided attention during encoding on females' and males' recognition of female and male faces. For female participants, divided attention impaired recognition performance for female faces to a greater extent than male faces in a face recognition paradigm (Study 1; N=113) and an eyewitness identification paradigm (Study 2; N=502). Analysis of remember-know judgments (Study 2) indicated that divided attention at encoding selectively reduced female participants' recollection of female faces at test. For male participants, divided attention selectively reduced recognition performance (and recollection) for male stimuli in Study 2, but had similar effects on recognition of male and female faces in Study 1. Overall, the results suggest that attention at encoding contributes to the female own-gender bias by facilitating the later recollection of female faces. Copyright © 2013 Elsevier B.V. All rights reserved.
2014-04-04
Effects of Photographic Aids (Photos of Faces) on Patient Recall of Their Clinical Care Team; Effects of Photographic Aids (Photos of Faces) on Clinician-patient Communication; Effects of Photographic Aids (Photos of Faces) on Overall Patient Satisfaction
Quintessence Reissner Nordström Anti de Sitter Black Holes and Joule Thomson Effect
NASA Astrophysics Data System (ADS)
Ghaffarnejad, H.; Yaraie, E.; Farsam, M.
2018-06-01
In this work we investigate corrections of the quintessence regime of the dark energy on the Joule-Thomson (JT) effect of the Reissner Nordström anti de Sitter (RNAdS) black hole. The quintessence dark energy has equation of state as p q = ω ρ q in which -1<ω <- 1/3. Our calculations are restricted to ansatz: ω = - 1 (the cosmological constant regime) and ω =- 2/3 (quintessence dark energy). To study the JT expansion of the AdS gas under the constant black hole mass, we calculate inversion temperature T i of the quintessence RNAdS black hole where its cooling phase is changed to heating phase at a particular (inverse) pressure P i . Position of the inverse point { T i , P i } is determined by crossing the inverse curves with the corresponding Gibbons-Hawking temperature on the T-P plan. We determine position of the inverse point versus different numerical values of the mass M and the charge Q of the quintessence AdS RN black hole. The cooling-heating phase transition (JT effect) is happened for M > Q in which the causal singularity is still covered by the horizon. Our calculations show sensitivity of the inverse point { T i , P i } position on the T-P plan to existence of the quintessence dark energy just for large numerical values of the AdS RN black holes charge Q. In other words the quintessence dark energy dose not affect on position of the inverse point when the AdS RN black hole takes on small charges.
Tracer SWIW tests in propped and un-propped fractures: parameter sensitivity issues, revisited
NASA Astrophysics Data System (ADS)
Ghergut, Julia; Behrens, Horst; Sauter, Martin
2017-04-01
Single-well injection-withdrawal (SWIW) or 'push-then-pull' tracer methods appear attractive for a number of reasons: less uncertainty on design and dimensioning, and lower tracer quantities required than for inter-well tests; stronger tracer signals, enabling easier and cheaper metering, and shorter metering duration required, reaching higher tracer mass recovery than in inter-well tests; last not least: no need for a second well. However, SWIW tracer signal inversion faces a major issue: the 'push-then-pull' design weakens the correlation between tracer residence times and georeservoir transport parameters, inducing insensitivity or ambiguity of tracer signal inversion w. r. to some of those georeservoir parameters that are supposed to be the target of tracer tests par excellence: pore velocity, transport-effective porosity, fracture or fissure aperture and spacing or density (where applicable), fluid/solid or fluid/fluid phase interface density. Hydraulic methods cannot measure the transport-effective values of such parameters, because pressure signals correlate neither with fluid motion, nor with material fluxes through (fluid-rock, or fluid-fluid) phase interfaces. The notorious ambiguity impeding parameter inversion from SWIW test signals has nourished several 'modeling attitudes': (i) regard dispersion as the key process encompassing whatever superposition of underlying transport phenomena, and seek a statistical description of flow-path collectives enabling to characterize dispersion independently of any other transport parameter, as proposed by Gouze et al. (2008), with Hansen et al. (2016) offering a comprehensive analysis of the various ways dispersion model assumptions interfere with parameter inversion from SWIW tests; (ii) regard diffusion as the key process, and seek for a large-time, asymptotically advection-independent regime in the measured tracer signals (Haggerty et al. 2001), enabling a dispersion-independent characterization of multiple-scale diffusion; (iii) attempt to determine both advective and non-advective transport parameters from one and the same conservative-tracer signal (relying on 'third-party' knowledge), or from twin signals of a so-called 'dual' tracer pair, e. g.: using tracers with contrasting reactivity and partitioning behavior to determine residual saturation in depleted oilfields (Tomich et al. 1973), or to determine advective parameters (Ghergut et al. 2014); using early-time signals of conservative and sorptive tracers for propped-fracture characterization (Karmakar et al. 2015); using mid-time signals of conservative tracers for a reservoir-borne inflow profiling in multi-frac systems (Ghergut et al. 2016), etc. The poster describes new uses of type-(iii) techniques for the specific purposes of shale-gas reservoir characterization, productivity monitoring, diagnostics and engineering of 're-frac' treatments, based on parameter sensitivity findings from German BMWi research project "TRENDS" (Federal Ministry for Economic Affairs and Energy, FKZ 0325515) and from the EU-H2020 project "FracRisk" (grant no. 640979).
The effect of face patch microstimulation on perception of faces and objects.
Moeller, Sebastian; Crapse, Trinity; Chang, Le; Tsao, Doris Y
2017-05-01
What is the range of stimuli encoded by face-selective regions of the brain? We asked how electrical microstimulation of face patches in macaque inferotemporal cortex affects perception of faces and objects. We found that microstimulation strongly distorted face percepts and that this effect depended on precise targeting to the center of face patches. While microstimulation had no effect on the percept of many non-face objects, it did affect the percept of some, including non-face objects whose shape is consistent with a face (for example, apples) as well as somewhat facelike abstract images (for example, cartoon houses). Microstimulation even perturbed the percept of certain objects that did not activate the stimulated face patch at all. Overall, these results indicate that representation of facial identity is localized to face patches, but activity in these patches can also affect perception of face-compatible non-face objects, including objects normally represented in other parts of inferotemporal cortex.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ahmed, Raef S.; Ove, Roger; Duan, Jun
2006-10-01
The treatment of maxillary sinus carcinoma with forward planning can be technically difficult when the neck also requires radiotherapy. This difficulty arises because of the need to spare the contralateral face while treating the bilateral neck. There is considerable potential for error in clinical setup and treatment delivery. We evaluated intensity-modulated radiotherapy (IMRT) as an improvement on forward planning, and compared several inverse planning IMRT platforms. A composite dose-volume histogram (DVH) was generated from a complex forward planned case. We compared the results with those generated by sliding window fixed field dynamic multileaf collimator (MLC) IMRT, using sets of coplanarmore » beams. All setups included an anterior posterior (AP) beam, and 3-, 5-, 7-, and 9-field configurations were evaluated. The dose prescription and objective function priorities were invariant. We also evaluated 2 commercial tomotherapy IMRT delivery platforms. DVH results from all of the IMRT approaches compared favorably with the forward plan. Results for the various inverse planning approaches varied considerably across platforms, despite an attempt to prescribe the therapy similarly. The improvement seen with the addition of beams in the fixed beam sliding window case was modest. IMRT is an effective means of delivering radiotherapy reliably in the complex setting of maxillary sinus carcinoma with neck irradiation. Differences in objective function definition and optimization algorithms can lead to unexpected differences in the final dose distribution, and our evaluation suggests that these factors are more significant than the beam arrangement or number of beams.« less
Microseismic imaging using a source function independent full waveform inversion method
NASA Astrophysics Data System (ADS)
Wang, Hanchen; Alkhalifah, Tariq
2018-07-01
At the heart of microseismic event measurements is the task to estimate the location of the source microseismic events, as well as their ignition times. The accuracy of locating the sources is highly dependent on the velocity model. On the other hand, the conventional microseismic source locating methods require, in many cases, manual picking of traveltime arrivals, which do not only lead to manual effort and human interaction, but also prone to errors. Using full waveform inversion (FWI) to locate and image microseismic events allows for an automatic process (free of picking) that utilizes the full wavefield. However, FWI of microseismic events faces incredible nonlinearity due to the unknown source locations (space) and functions (time). We developed a source function independent FWI of microseismic events to invert for the source image, source function and the velocity model. It is based on convolving reference traces with these observed and modelled to mitigate the effect of an unknown source ignition time. The adjoint-state method is used to derive the gradient for the source image, source function and velocity updates. The extended image for the source wavelet in Z axis is extracted to check the accuracy of the inverted source image and velocity model. Also, angle gathers are calculated to assess the quality of the long wavelength component of the velocity model. By inverting for the source image, source wavelet and the velocity model simultaneously, the proposed method produces good estimates of the source location, ignition time and the background velocity for synthetic examples used here, like those corresponding to the Marmousi model and the SEG/EAGE overthrust model.
1D Cole-Cole inversion of TEM transients influenced by induced polarization
NASA Astrophysics Data System (ADS)
Seidel, Marc; Tezkan, Bülent
2017-03-01
Effects of induced polarization (IP) can have an impact on time-domain electromagnetic measurements (TEM) and may lead to sign reversals in the recorded transients. To study these IP effects on TEM data, a new 1D inversion algorithm was developed for both, the central-loop and the separate-loop TEM configurations using the Cole-Cole relaxation model. 1D forward calculations for a homogeneous half-space were conducted with the aim of analyzing the impacts of the Cole-Cole parameters on TEM transients with respect to possible sign reversals. The forward modelings showed that the variation of different parameters have comparable effects on the TEM transients. This leads to an increasing number of equivalent models as a result of inversion calculations. Subsequently, 1D inversions of synthetic data were performed to study the potentials and limitations of the algorithm regarding the resolution of the Cole-Cole parameters. In order to achieve optimal inversion results, it was essential to error-weight the data points in the direct vicinity of sign reversals. The obtained findings were eventually adopted on the inversion of real field data which contained considerable IP signatures such as sign reversals. One field data set was recorded at the Nakyn kimberlite field in Western Yakutiya, Russia, in the central-loop configuration. Another field data set originates from a waste site in Cologne, Germany, and was measured utilizing the separate-loop configuration.
Alves, Joao M; Chikhi, Lounès; Amorim, António; Lopes, Alexandra M
2014-04-01
For decades, chromosomal inversions have been regarded as fascinating evolutionary elements as they are expected to suppress recombination between chromosomes with opposite orientations, leading to the accumulation of genetic differences between the two configurations over time. Here, making use of publicly available population genotype data for the largest polymorphic inversion in the human genome (8p23-inv), we assessed whether this inhibitory effect of inversion rearrangements led to significant differences in the recombination landscape of two homologous DNA segments, with opposite orientation. Our analysis revealed that the accumulation of genetic differentiation is positively correlated with the variation in recombination profiles. The observed recombination dissimilarity between inversion types is consistent across all populations analyzed and surpasses the effects of geographic structure, suggesting that both structures (orientations) have been evolving independently over an extended period of time, despite being subjected to the very same demographic history. Aside this mainly independent evolution, we also identified a short segment (350 kb, <10% of the whole inversion) in the central region of the inversion where the genetic divergence between the two structural haplotypes is diminished. Although it is difficult to demonstrate it, this could be due to gene flow (possibly via double-crossing over events), which is consistent with the higher recombination rates surrounding this segment. This study demonstrates for the first time that chromosomal inversions influence the recombination landscape at a fine-scale and highlights the role of these rearrangements as drivers of genome evolution.
The origin, global distribution, and functional impact of the human 8p23 inversion polymorphism.
Salm, Maximilian P A; Horswell, Stuart D; Hutchison, Claire E; Speedy, Helen E; Yang, Xia; Liang, Liming; Schadt, Eric E; Cookson, William O; Wierzbicki, Anthony S; Naoumova, Rossi P; Shoulders, Carol C
2012-06-01
Genomic inversions are an increasingly recognized source of genetic variation. However, a lack of reliable high-throughput genotyping assays for these structures has precluded a full understanding of an inversion's phylogenetic, phenotypic, and population genetic properties. We characterize these properties for one of the largest polymorphic inversions in man (the ∼4.5-Mb 8p23.1 inversion), a structure that encompasses numerous signals of natural selection and disease association. We developed and validated a flexible bioinformatics tool that utilizes SNP data to enable accurate, high-throughput genotyping of the 8p23.1 inversion. This tool was applied retrospectively to diverse genome-wide data sets, revealing significant population stratification that largely follows a clinal "serial founder effect" distribution model. Phylogenetic analyses establish the inversion's ancestral origin within the Homo lineage, indicating that 8p23.1 inversion has occurred independently in the Pan lineage. The human inversion breakpoint was localized to an inverted pair of human endogenous retrovirus elements within the large, flanking low-copy repeats; experimental validation of this breakpoint confirmed these elements as the likely intermediary substrates that sponsored inversion formation. In five data sets, mRNA levels of disease-associated genes were robustly associated with inversion genotype. Moreover, a haplotype associated with systemic lupus erythematosus was restricted to the derived inversion state. We conclude that the 8p23.1 inversion is an evolutionarily dynamic structure that can now be accommodated into the understanding of human genetic and phenotypic diversity.
Through the eyes of the own-race bias: eye-tracking and pupillometry during face recognition.
Wu, Esther Xiu Wen; Laeng, Bruno; Magnussen, Svein
2012-01-01
People are generally better at remembering faces of their own race than faces of a different race, and this effect is known as the own-race bias (ORB) effect. We used eye-tracking and pupillometry to investigate whether Caucasian and Asian face stimuli elicited different-looking patterns in Caucasian participants in a face-memory task. Consistent with the ORB effect, we found better recognition performance for own-race faces than other-race faces, and shorter response times. In addition, at encoding, eye movements and pupillary responses to Asian faces (i.e., the other race) were different from those to Caucasian faces (i.e., the own race). Processing of own-race faces was characterized by more active scanning, with a larger number of shorter fixations, and more frequent saccades. Moreover, pupillary diameters were larger when viewing other-race than own-race faces, suggesting a greater cognitive effort when encoding other-race faces.
Facilitation of face recognition through the retino-tectal pathway.
Nakano, Tamami; Higashida, Noriko; Kitazawa, Shigeru
2013-08-01
Humans can shift their gazes faster to human faces than to non-face targets during a task in which they are required to choose between face and non-face targets. However, it remains unclear whether a direct projection from the retina to the superior colliculus is specifically involved in this facilitated recognition of faces. To address this question, we presented a pair of face and non-face pictures to participants modulated in greyscale (luminance-defined stimuli) in one condition and modulated in a blue-yellow scale (S-cone-isolating stimuli) in another. The information of the S-cone-isolating stimuli is conveyed through the retino-geniculate pathway rather than the retino-tectal pathway. For the luminance stimuli, the reaction time was shorter towards a face than towards a non-face target. The facilitatory effect while choosing a face disappeared with the S-cone stimuli. Moreover, fearful faces elicited a significantly larger facilitatory effect relative to neutral faces, when the face (with or without emotion) and non-face stimuli were presented in greyscale. The effect of emotional expressions disappeared with the S-cone stimuli. In contrast to the S-cone stimuli, the face facilitatory effect was still observed with negated stimuli that were prepared by reversing the polarity of the original colour pictures and looked as unusual as the S-cone stimuli but still contained luminance information. These results demonstrate that the face facilitatory effect requires the facial and emotional information defined by luminance, suggesting that the luminance information conveyed through the retino-tectal pathway is responsible for the faster recognition of human faces. Copyright © 2013 Elsevier Ltd. All rights reserved.
Doped organic transistors operating in the inversion and depletion regime
Lüssem, Björn; Tietze, Max L.; Kleemann, Hans; Hoßbach, Christoph; Bartha, Johann W.; Zakhidov, Alexander; Leo, Karl
2013-01-01
The inversion field-effect transistor is the basic device of modern microelectronics and is nowadays used more than a billion times on every state-of-the-art computer chip. In the future, this rigid technology will be complemented by flexible electronics produced at extremely low cost. Organic field-effect transistors have the potential to be the basic device for flexible electronics, but still need much improvement. In particular, despite more than 20 years of research, organic inversion mode transistors have not been reported so far. Here we discuss the first realization of organic inversion transistors and the optimization of organic depletion transistors by our organic doping technology. We show that the transistor parameters—in particular, the threshold voltage and the ON/OFF ratio—can be controlled by the doping concentration and the thickness of the transistor channel. Injection of minority carriers into the doped transistor channel is achieved by doped contacts, which allows forming an inversion layer. PMID:24225722
The other-race effect does not apply to infant faces: An ERP attentional study.
Proverbio, Alice Mado; De Gabriele, Valeria
2017-03-29
It is known that paedomorphic characteristics, called "baby schema" by Lorenz, trigger an orienting response in adults, are judged as attractive and stimulate parental care. On the other hand, it is known that ethnicity may influence face encoding, with an advantage in recognizing faces of their own ethnicity (called own-race effect). Some have argued that this effect holds also for infant faces, which conflicts with the "baby schema" phenomenon. The aim of the study was to investigate the possible presence of the own-race effect on infant vs. adult face processing. Seventeen Caucasian students participated to the study. Their EEG/ERPs were recorded as they watched 400 pictures of adult and infant faces of different ethnicity (half Caucasian, half non-Caucasian), and subsequently responded to a target orientation. The behavioral results showed that responses were faster when the target was preceded by a child face, which enhanced the arousal level, regardless of ethnicity. The electrophysiological results showed an enhanced anterior N2 response to infant than adult faces, and a lack of ORE effect only for infant faces. Overall, the data indicate that baby faces automatically attract the adult viewer's attention and that face ethnicity has no effect on this innate response. Copyright © 2017 Elsevier Ltd. All rights reserved.
From development to aging: Holistic face perception in children, younger and older adults.
Meinhardt-Injac, Bozana; Boutet, Isabelle; Persike, Malte; Meinhardt, Günter; Imhof, Margarete
2017-01-01
Few published reports examine the development of holistic face processing across the lifespan such that face-specific processes are adequately differentiated from general developmental effects. To address this gap in the literature, we used the complete design of the composite paradigm (Richler & Gauthier, 2014) with faces and non-face control objects (watches) to investigate holistic processing in children (8-10years), young adults (20-32years) and older adults (65-78years). Several modifications to past research designs were introduced to improve the ability to draw conclusions about the development of holistic processing in terms of face-specificity, response bias, and age-related differences in attention. Attentional focus (narrow vs. wide focus at study) influenced the magnitude of the composite effect without eliminating holistic face processing in all age groups. Young adults showed large composite effects for faces, but none for watches. In contrast, older adults and children showed composite effects for both faces and watches, although the effects for faces were larger. Our findings suggest that holistic processing, as measured by the composite effect, might be moderated by less efficient attentional control in children and older adults. The study also underscores the importance of including comparable complex objects when investigating face processing across the lifespan. Copyright © 2016 Elsevier B.V. All rights reserved.
... medications or doctor visits! Yoga and Recreational Body Inversion The long-term effects of repeatedly assuming a ... shoulder and headstands or any other recreational body inversion exercises that result in head-down or inverted ...
Rotation Reveals the Importance of Configural Cues in Handwritten Word Perception
Barnhart, Anthony S.; Goldinger, Stephen D.
2013-01-01
A dramatic perceptual asymmetry occurs when handwritten words are rotated 90° in either direction. Those rotated in a direction consistent with their natural tilt (typically clockwise) become much more difficult to recognize, relative to those rotated in the opposite direction. In Experiment 1, we compared computer-printed and handwritten words, all equated for degrees of leftward and rightward tilt, and verified the phenomenon: The effect of rotation was far larger for cursive words, especially when rotated in a tilt-consistent direction. In Experiment 2, we replicated this pattern with all items presented in visual noise. In both experiments, word frequency effects were larger for computer-printed words and did not interact with rotation. The results suggest that handwritten word perception requires greater configural processing, relative to computer print, because handwritten letters are variable and ambiguous. When words are rotated, configural processing suffers, particularly when rotation exaggerates natural tilt. Our account is similar to theories of the “Thatcher Illusion,” wherein face inversion disrupts holistic processing. Together, the findings suggest that configural, word-level processing automatically increases when people read handwriting, as letter-level processing becomes less reliable. PMID:23589201
Kingsolver, Joel
1981-03-01
To explore principles of organismic design in fluctuating environments, morphological design of the leaf of the pitcher-plant, Sarracenia purpurea, was studied for a population in northern Michigan. The design criterion focused upon the leaf shape and minimum size which effectively avoids leaf desiccation (complete loss of fluid from the leaf cavity) in the face of fluctuating rainfall and meteorological conditions. Bowl- and pitcher-shaped leaves were considered. Simulations show that the pitcher geometry experiences less frequent desiccation than bowls of the same size. Desiccation frequency is inversely related to leaf size; the size distribution of pitcher leaves in the field shows that the majority of pitchers desiccate only 1-3 times per season on average, while smaller pitchers may average up to 8 times per season. A linear filter model of an organism in a fluctuating environment is presented, in which the organism selectively filters the temporal patterns of environmental input. General measures of rainfall predictability based upon information theory and spectral analysis are consistent with the model of a pitcher leaf as a low-pass (frequency) filter which avoids desiccation by eliminating high-frequency rainfall variability.
Another look at contrast in multiple schedules
Williams, Ben A.
1983-01-01
Recent research on multiple schedule interactions is reviewed. Contrary to formulations that view contrast as the result of elicited behavior controlled by the stimulus-reinforcer contingency (e.g., additivity theory), the major controlling variable is the relative rate of reinforcement, which cannot be reduced to some combination of stimulus-reinforcer and response-reinforcer effects. Other recent theoretical formulations are also reviewed and all are found to face serious counterevidence. The best description of the available data continues to be in terms of the “context of reinforcement,” but Herrnstein's (1970) formulation of the basis of such context effects appears to be inadequate. An alternative conception is provided by Catania's concept of “inhibition by reinforcement,” by which rate of responding is inversely related to the average rate of reinforcement in the situation. Such a conception is related to Gibbon's recent scalar-expectancy account of autoshaping and Fantino's delay-reduction model of conditioned reinforcement, suggesting that a common set of principles determines several diverse conditioning phenomena. However, the empirical status of such a description remains uncertain, because recent evidence shows that schedule interactions are temporally asymmetric, depending primarily upon the conditions of reinforcement that follow a schedule component. PMID:16812325
Cuperus, Nienke; van den Hout, Wilbert B; Hoogeboom, Thomas J; van den Hoogen, Frank H J; Vliet Vlieland, Thea P M; van den Ende, Cornelia H M
2016-04-01
To evaluate, from a societal perspective, the cost utility and cost effectiveness of a nonpharmacologic face-to-face treatment program compared with a telephone-based treatment program for patients with generalized osteoarthritis (GOA). An economic evaluation was carried out alongside a randomized clinical trial involving 147 patients with GOA. Program costs were estimated from time registrations. One-year medical and nonmedical costs were estimated using cost questionnaires. Quality-adjusted life years (QALYs) were estimated using the EuroQol (EQ) classification system, EQ rating scale, and the Short Form 6D (SF-6D). Daily function was measured using the Health Assessment Questionnaire (HAQ) disability index (DI). Cost and QALY/effect differences were analyzed using multilevel regression analysis and cost-effectiveness acceptability curves. Medical costs of the face-to-face treatment and telephone-based treatment were estimated at €387 and €252, respectively. The difference in total societal costs was nonsignificantly in favor of the face-to-face program (difference €708; 95% confidence interval [95% CI] -€5,058, €3,642). QALYs were similar for both groups according to the EQ, but were significantly in favor of the face-to-face group, according to the SF-6D (difference 0.022 [95% CI 0.000, 0.045]). Daily function was similar according to the HAQ DI. Since both societal costs and QALYs/effects were in favor of the face-to-face program, the economic assessment favored this program, regardless of society's willingness to pay. There was a 65-90% chance that the face-to-face program had better cost utility and a 60-70% chance of being cost effective. This economic evaluation from a societal perspective showed that a nonpharmacologic, face-to-face treatment program for patients with GOA was likely to be cost effective, relative to a telephone-based program. © 2016, American College of Rheumatology.
Li, Tian-Tian; Lu, Yong
2014-11-07
This study on the subliminal affective priming effects of faces displaying various levels of arousal employed event-related potentials (ERPs). The participants were asked to rate the arousal of ambiguous medium-arousing faces that were preceded by high- or low-arousing priming faces presented subliminally. The results revealed that the participants exhibited arousal-consistent variation in their arousal level ratings of the probe faces exclusively in the negative prime condition. Compared with high-arousing faces, the low-arousing faces tended to elicit greater late positive component (LPC, 450-660ms) and greater N400 (330-450ms) potentials. These findings support the following conclusions: (1) the effect of subliminal affective priming of faces can be detected in the affective arousal dimension; (2) valence may influence the subliminal affective priming effect of the arousal dimension of emotional stimuli; and (3) the subliminal affective priming effect of face arousal occurs when the prime stimulus affects late-stage processing of the probe. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Impurity effect of iron(III) on the growth of potassium sulfate crystal in aqueous solution
NASA Astrophysics Data System (ADS)
Kubota, Noriaki; Katagiri, Ken-ichi; Yokota, Masaaki; Sato, Akira; Yashiro, Hitoshi; Itai, Kazuyoshi
1999-01-01
Growth rates of the {1 1 0} faces of a potassium sulfate crystal were measured in a flow cell in the presence of traces of impurity Fe(III) (up to 2 ppm) over the range of pH=2.5-6.0. The growth rate was significantly suppressed by the impurity. The effect became stronger as the impurity concentration was increased and at pH<5. It became weaker with increasing supersaturation. It also became weaker as the pH was increased and at pH>5 it finally disappeared completely. The concentration and supersaturation effects on the impurity action were reasonably explained with a model proposed by Kubota and Mullin [J. Crystal Growth, 152 (1995) 203]. The surface coverage of the active sites by Fe(III) is estimated to increase linearly on increasing its concentration in solution in the range examined by growth experiments. The impurity effectiveness factor is confirmed to increase inversely proportional to the supersaturation as predicted by the model. Apart from the discussion based on the model, the pH effect on the impurity action is qualitatively explained by assuming that the first hydrolysis product of aqua Fe(III) complex compound, [Fe(H 2O) 5(OH)] 2+, is both growth suppression and adsorption active, but the second hydrolysis product, [Fe(H 2O) 4(OH) 2] +, is only adsorption active.
Modeling the Effects of Meteorological Conditions on the Neutron Flux
2017-05-22
a statistical model that predicts environmental neutron background as a function of five meteorological variables: inverse barometric pressure...variable of the model was inverse barometric pressure with a contribution an order of magnitude larger than any other variable’s contribution. The...is based on the sensitivity of each sensor. . . . . . . . . . . . . . . . . . . . . . . . . . 25 3.2 Neutron counts from the LNS and inverse pressure
Chess masters show a hallmark of face processing with chess.
Boggan, Amy L; Bartlett, James C; Krawczyk, Daniel C
2012-02-01
Face processing has several distinctive hallmarks that researchers have attributed either to face-specific mechanisms or to extensive experience distinguishing faces. Here, we examined the face-processing hallmark of selective attention failure--as indexed by the congruency effect in the composite paradigm--in a domain of extreme expertise: chess. Among 27 experts, we found that the congruency effect was equally strong with chessboards and faces. Further, comparing these experts with recreational players and novices, we observed a trade-off: Chess expertise was positively related to the congruency effect with chess yet negatively related to the congruency effect with faces. These and other findings reveal a case of expertise-dependent, facelike processing of objects of expertise and suggest that face and expert-chess recognition share common processes.
Harijan, Rajesh K.; Zoi, Ioanna; Antoniou, Dimitri; Schwartz, Steven D.; Schramm, Vern L.
2017-01-01
Heavy-enzyme isotope effects (15N-, 13C-, and 2H-labeled protein) explore mass-dependent vibrational modes linked to catalysis. Transition path-sampling (TPS) calculations have predicted femtosecond dynamic coupling at the catalytic site of human purine nucleoside phosphorylase (PNP). Coupling is observed in heavy PNPs, where slowed barrier crossing caused a normal heavy-enzyme isotope effect (kchem light/kchem heavy > 1.0). We used TPS to design mutant F159Y PNP, predicted to improve barrier crossing for heavy F159Y PNP, an attempt to generate a rare inverse heavy-enzyme isotope effect (kchem light/kchem heavy < 1.0). Steady-state kinetic comparison of light and heavy native PNPs to light and heavy F159Y PNPs revealed similar kinetic properties. Pre–steady-state chemistry was slowed 32-fold in F159Y PNP. Pre–steady-state chemistry compared heavy and light native and F159Y PNPs and found a normal heavy-enzyme isotope effect of 1.31 for native PNP and an inverse effect of 0.75 for F159Y PNP. Increased isotopic mass in F159Y PNP causes more efficient transition state formation. Independent validation of the inverse isotope effect for heavy F159Y PNP came from commitment to catalysis experiments. Most heavy enzymes demonstrate normal heavy-enzyme isotope effects, and F159Y PNP is a rare example of an inverse effect. Crystal structures and TPS dynamics of native and F159Y PNPs explore the catalytic-site geometry associated with these catalytic changes. Experimental validation of TPS predictions for barrier crossing establishes the connection of rapid protein dynamics and vibrational coupling to enzymatic transition state passage. PMID:28584087
Anomalous cooling and heating - the Mpemba effect and its inverse
NASA Astrophysics Data System (ADS)
Lu, Zhiyue; Raz, Oren
Under certain conditions, it takes a shorter time to cool a hot object than to cool the same object initiated at a lower temperature. This counter-intuitive phenomenon - the 'Mpemba Effect'\\x9D, has been observed in a variety of systems. So far, no generic mechanism was suggested to explain this effect. In the theoretical framework of non-equilibrium thermodynamics, we construct a model to describe this effect and illustrates the fundamental principles behind it. In addition, we predict and demonstrate an inverse Mpemba effect: it can take a shorter time to heat a cold object than a warmer one. We derive sufficient conditions for the occurrences of both the forward and the inverse Mpemba effects, and suggest experiments to further study the non-equilibrium nature of these effects. Z.L. acknowledges financial support from the NSF under Grant DMR-1206971. O.R. acknowledges financial support from the James S. McDonnell Foundation.
Highlights from two years of geoelectrical monitoring of permafrost at the Magnetköpfl/Kitzsteinhorn
NASA Astrophysics Data System (ADS)
Jochum, Birgit; Ottowitz, David; Pfeiler, Stefan; Supper, Robert; Keuschnig, Markus; Hartmeyer, Ingo; Kim, Jung-Ho
2014-05-01
Changes of climate parameters due to global warming generate increased permafrost warming and deglaciation in alpine regions. The area of interest is the Magnetköpfl, a peak below the Kitzsteinhorn (3203 m), where scientists observe increasing rock instability due to the probable degradation of permafrost and the rapid lowering of the glacier surfaces adjacent to the rock faces (loss of natural abutment, exposure of rock to atmospheric influences). Geoelectric measurements are an adequate method to measure permafrost, since the underground electric resistivity is highly dependent on temperature and the amount of unfrozen pore water. In October 2011 a geoelectrical monitoring profile with the GEOMON4D was installed on the north facing ridge of the Magnetköpfl. Measurements of soil temperature on the profile support the interpretation of geoelectric data. Maximum active layer depth at the Magnetköpfl is approximately 3 m. Seasonal variations of ground temperature can be observed up to a depth of 8-10 m below surface. The two year period of data collection allows us to analyse time series of average apparent resistivities compared with the climatic seasons. It can be seen that different temperature periods have a direct correlation to average apparent resistivity. Inversion results of geoelectrical monitoring data are derived from an innovative 4D resistivity inversion approach (Kim et al, 2013). In three selected events (thawing and freezing in spring, thawing in summer, freezing in fall) difference images of the 4D inversion show the depth range of the temperature influence. The temperature sensors at the profile only reach 0.8 m below ground level.The geoelectrical monitoring data is able to deliver far more (thermal) information than single point temperature measurements since the underground electric resistivity is highly dependent on temperature. The geoelectrical monitoring is supported by the project "TEMPEL", funded by the Federal Ministry for Transport, Innovation & Technology (BMVIT) and the Austrian Science Fund (FWF): TRP 175-N21 and internal funds of the Geological Survey of Austria. The recording of the ground temperature is conducted within MOREXPERT administered by alpS - Centre for Climate Change Adaptation and the University of Salzburg. Kim J.-H., Supper R., Tsourlos P. and Yi M.-J. 2013. Four-dimensional inversion of resistivity monitoring data through Lp norm minimizations. Geophysical Journal International, 2013-11-21 Supper R., Ottowitz D., Jochum B., Römer A., Pfeiler S., Kauer S., Keuschnig M. and Ita A. Geoelectrical monitoring of frozen ground and permafrost in alpine areas: field studies and considerations towards an improved measuring technology. Near Surface Geophysics, 2014, 12, 93-115
Analysis of space telescope data collection system
NASA Technical Reports Server (NTRS)
Ingels, F. M.; Schoggen, W. O.
1982-01-01
An analysis of the expected performance for the Multiple Access (MA) system is provided. The analysis covers the expected bit error rate performance, the effects of synchronization loss, the problem of self-interference, and the problem of phase ambiguity. The problem of false acceptance of a command word due to data inversion is discussed. A mathematical determination of the probability of accepting an erroneous command word due to a data inversion is presented. The problem is examined for three cases: (1) a data inversion only, (2) a data inversion and a random error within the same command word, and a block (up to 256 48-bit words) containing both a data inversion and a random error.
The inverse benefit law: how drug marketing undermines patient safety and public health.
Brody, Howard; Light, Donald W
2011-03-01
Recent highly publicized withdrawals of drugs from the market because of safety concerns raise the question of whether these events are random failures or part of a recurring pattern. The inverse benefit law, inspired by Hart's inverse care law, states that the ratio of benefits to harms among patients taking new drugs tends to vary inversely with how extensively the drugs are marketed. The law is manifested through 6 basic marketing strategies: reducing thresholds for diagnosing disease, relying on surrogate endpoints, exaggerating safety claims, exaggerating efficacy claims, creating new diseases, and encouraging unapproved uses. The inverse benefit law highlights the need for comparative effectiveness research and other reforms to improve evidence-based prescribing.
The mediating effects of job satisfaction on turnover intention for long-term care nurses in Taiwan.
Kuo, Huai-Ting; Lin, Kuan-Chia; Li, I-Chuan
2014-03-01
This study explores the mediating effects of job satisfaction on work stress and turnover intention among long-term care nurses in Taiwan. Healthcare institutions face a nursing shortage, and it is important to examine the factors that influence turnover intention among nurses. Excessive levels of work stress may lead to employee dissatisfaction and a significant inverse relationship between work stress and job satisfaction, including subsequent effects on turnover among nurses. However, little is known about the mediating role of job satisfaction on work stress and turnover intention among long-term care nurses. A cross-sectional survey and a correlation design were used. Multistage linear regression was used to test the mediation model. This study showed that job satisfaction significantly mediated the relationship between work stress and turnover intention. Thirty-eight percent of the variance in turnover intention explained by work stress was accounted for by the mediation pathway. The results of this study showed that higher job satisfaction significantly decreased work stress and turnover intention among long-term care nurses. This study provides nursing administrators with a resource to build a supportive environment to increase nurses' job satisfaction and to decrease their stress and turnover. © 2013 John Wiley & Sons Ltd.
Social contact and other-race face processing in the human brain
Silvert, Laetitia; Hewstone, Miles; Nobre, Anna C.
2008-01-01
The present study investigated the influence social factors upon the neural processing of faces of other races using event-related potentials. A multi-tiered approach was used to identify face-specific stages of processing, to test for effects of race-of-face upon processing at these stages and to evaluate the impact of social contact and individuating experience upon these effects. The results showed that race-of-face has significant effects upon face processing, starting from early perceptual stages of structural encoding, and that social factors may play an important role in mediating these effects. PMID:19015091
McKone, Elinor; Stokes, Sacha; Liu, Jia; Cohan, Sarah; Fiorentini, Chiara; Pidcock, Madeleine; Yovel, Galit; Broughton, Mary; Pelleg, Michel
2012-01-01
Other-race and other-ethnicity effects on face memory have remained a topic of consistent research interest over several decades, across fields including face perception, social psychology, and forensic psychology (eyewitness testimony). Here we demonstrate that the Cambridge Face Memory Test format provides a robust method for measuring these effects. Testing the Cambridge Face Memory Test original version (CFMT-original; European-ancestry faces from Boston USA) and a new Cambridge Face Memory Test Chinese (CFMT-Chinese), with European and Asian observers, we report a race-of-face by race-of-observer interaction that was highly significant despite modest sample size and despite observers who had quite high exposure to the other race. We attribute this to high statistical power arising from the very high internal reliability of the tasks. This power also allows us to demonstrate a much smaller within-race other ethnicity effect, based on differences in European physiognomy between Boston faces/observers and Australian faces/observers (using the CFMT-Australian). PMID:23118912
NASA Astrophysics Data System (ADS)
Vitello, Peter; Garza, Raul; Hernandez, Andy; Souers, P. Clark
2007-12-01
We explore various relations for the detonation energy and velocity as they relate to the inverse radius of the cylinder. The effective detonation rate-inverse slope relation seen in reactive flow models can be used to derive the familiar Eyring equation. Generalized inverse radii can be shown to fit large quantities of cylinder results. A rough relation between detonation energy and detonation velocity is found from collected JWL values. Cylinder test data for ammonium nitrate mixes down to 6.35 mm radii are presented, and a size energy effect is shown to exist in the Cylinder test data. The relation that detonation energy is roughly proportional to the square of the detonation velocity is shown by data and calculation.
Inverse modeling methods for indoor airborne pollutant tracking: literature review and fundamentals.
Liu, X; Zhai, Z
2007-12-01
Reduction in indoor environment quality calls for effective control and improvement measures. Accurate and prompt identification of contaminant sources ensures that they can be quickly removed and contaminated spaces isolated and cleaned. This paper discusses the use of inverse modeling to identify potential indoor pollutant sources with limited pollutant sensor data. The study reviews various inverse modeling methods for advection-dispersion problems and summarizes the methods into three major categories: forward, backward, and probability inverse modeling methods. The adjoint probability inverse modeling method is indicated as an appropriate model for indoor air pollutant tracking because it can quickly find source location, strength and release time without prior information. The paper introduces the principles of the adjoint probability method and establishes the corresponding adjoint equations for both multi-zone airflow models and computational fluid dynamics (CFD) models. The study proposes a two-stage inverse modeling approach integrating both multi-zone and CFD models, which can provide a rapid estimate of indoor pollution status and history for a whole building. Preliminary case study results indicate that the adjoint probability method is feasible for indoor pollutant inverse modeling. The proposed method can help identify contaminant source characteristics (location and release time) with limited sensor outputs. This will ensure an effective and prompt execution of building management strategies and thus achieve a healthy and safe indoor environment. The method can also help design optimal sensor networks.
LES on Plume Dispersion in the Convective Boundary Layer Capped by a Temperature Inversion
NASA Astrophysics Data System (ADS)
Nakayama, Hiromasa; Tamura, Tetsuro; Abe, Satoshi
Large-eddy simulation (LES) is applied to the problem of plume dispersion in the spatially-developing convective boundary layer (CBL) capped by a temperature inversion. In order to generate inflow turbulence with buoyant forcing, we first, simulate the neutral boundary layer flow (NBL) in the driver region using Lund's method. At the same time, the temperature profile possessing the inversion part is imposed at the entrance of the driver region and the temperature field is calculated as a passive scalar. Next, the buoyancy effect is introduced into the flow field in the main region. We evaluate the applicability of the LES model for atmospheric dispersion in the CBL flow and compare the characteristics of plume dispersion in the CBL flow with those in the neutral boundary layer. The Richardson number based on the temperature increment across the inversion obtained by the present LES model is 22.4 and the capping effect of the temperature inversion can be captured qualitatively in the upper portion of the CBL. Characteristics of flow and temperature fields in the main portion of CBL flow are similar to those of previous experiments[1],[2] and observations[3]. Concerning dispersion behavior, we also find that mean concentrations decrease immediately above the inversion height and the peak values of r.m.s concentrations are located near the inversion height at larger distances from the point source.
Projected change in characteristics of near surface temperature inversions for southeast Australia
NASA Astrophysics Data System (ADS)
Ji, Fei; Evans, Jason Peter; Di Luca, Alejandro; Jiang, Ningbo; Olson, Roman; Fita, Lluis; Argüeso, Daniel; Chang, Lisa T.-C.; Scorgie, Yvonne; Riley, Matt
2018-05-01
Air pollution has significant impacts on human health. Temperature inversions, especially near surface temperature inversions, can amplify air pollution by preventing convective movements and trapping pollutants close to the ground, thus decreasing air quality and increasing health issues. This effect of temperature inversions implies that trends in their frequency, strength and duration can have important implications for air quality. In this study, we evaluate the ability of three reanalysis-driven high-resolution regional climate model (RCM) simulations to represent near surface inversions at 9 sounding sites in southeast Australia. Then we use outputs of 12 historical and future RCM simulations (each with three time periods: 1990-2009, 2020-2039, and 2060-2079) from the NSW/ACT (New South Wales/Australian Capital Territory) Regional Climate Modelling (NARCliM) project to investigate changes in near surface temperature inversions. The results show that there is a substantial increase in the strength of near surface temperature inversions over southeast Australia which suggests that future inversions may intensify poor air quality events. Near surface inversions and their future changes have clear seasonal and diurnal variations. The largest differences between simulations are associated with the driving GCMs, suggesting that the large-scale circulation plays a dominant role in near surface inversion strengths.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yao, Jie, E-mail: yjie2@uh.edu; Lesage, Anne-Cécile; Hussain, Fazle
2014-12-15
The reversion of the Born-Neumann series of the Lippmann-Schwinger equation is one of the standard ways to solve the inverse acoustic scattering problem. One limitation of the current inversion methods based on the reversion of the Born-Neumann series is that the velocity potential should have compact support. However, this assumption cannot be satisfied in certain cases, especially in seismic inversion. Based on the idea of distorted wave scattering, we explore an inverse scattering method for velocity potentials without compact support. The strategy is to decompose the actual medium as a known single interface reference medium, which has the same asymptoticmore » form as the actual medium and a perturbative scattering potential with compact support. After introducing the method to calculate the Green’s function for the known reference potential, the inverse scattering series and Volterra inverse scattering series are derived for the perturbative potential. Analytical and numerical examples demonstrate the feasibility and effectiveness of this method. Besides, to ensure stability of the numerical computation, the Lanczos averaging method is employed as a filter to reduce the Gibbs oscillations for the truncated discrete inverse Fourier transform of each order. Our method provides a rigorous mathematical framework for inverse acoustic scattering with a non-compact support velocity potential.« less
Beneficial effects of verbalization and visual distinctiveness on remembering and knowing faces.
Brown, Charity; Lloyd-Jones, Toby J
2006-03-01
We examined the effect of verbally describing faces upon visual memory. In particular, we examined the locus of the facilitative effects of verbalization by manipulating the visual distinctiveness ofthe to-be-remembered faces and using the remember/know procedure as a measure of recognition performance (i.e., remember vs. know judgments). Participants were exposed to distinctive faces intermixed with typical faces and described (or not, in the control condition) each face following its presentation. Subsequently, the participants discriminated the original faces from distinctive and typical distractors in a yes/no recognition decision and made remember/know judgments. Distinctive faces elicited better discrimination performance than did typical faces. Furthermore, for both typical and distinctive faces, better discrimination performance was obtained in the description than in the control condition. Finally, these effects were evident for both recollection- and familiarity-based recognition decisions. We argue that verbalization and visual distinctiveness independently benefit face recognition, and we discuss these findings in terms of the nature of verbalization and the role of recollective and familiarity-based processes in recognition.
Adaptation effects to attractiveness of face photographs and art portraits are domain-specific
Hayn-Leichsenring, Gregor U.; Kloth, Nadine; Schweinberger, Stefan R.; Redies, Christoph
2013-01-01
We studied the neural coding of facial attractiveness by investigating effects of adaptation to attractive and unattractive human faces on the perceived attractiveness of veridical human face pictures (Experiment 1) and art portraits (Experiment 2). Experiment 1 revealed a clear pattern of contrastive aftereffects. Relative to a pre-adaptation baseline, the perceived attractiveness of faces was increased after adaptation to unattractive faces, and was decreased after adaptation to attractive faces. Experiment 2 revealed similar aftereffects when art portraits rather than face photographs were used as adaptors and test stimuli, suggesting that effects of adaptation to attractiveness are not restricted to facial photographs. Additionally, we found similar aftereffects in art portraits for beauty, another aesthetic feature that, unlike attractiveness, relates to the properties of the image (rather than to the face displayed). Importantly, Experiment 3 showed that aftereffects were abolished when adaptors were art portraits and face photographs were test stimuli. These results suggest that adaptation to facial attractiveness elicits aftereffects in the perception of subsequently presented faces, for both face photographs and art portraits, and that these effects do not cross image domains. PMID:24349690
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bender, Edward T.; Hardcastle, Nicholas; Tome, Wolfgang A.
2012-01-15
Purpose: Deformable image registration (DIR) is necessary for accurate dose accumulation between multiple radiotherapy image sets. DIR algorithms can suffer from inverse and transitivity inconsistencies. When using deformation vector fields (DVFs) that exhibit inverse-inconsistency and are nontransitive, dose accumulation on a given image set via different image pathways will lead to different accumulated doses. The purpose of this study was to investigate the dosimetric effect of and propose a postprocessing solution to reduce inverse consistency and transitivity errors. Methods: Four MVCT images and four phases of a lung 4DCT, each with an associated calculated dose, were selected for analysis. DVFsmore » between all four images in each data set were created using the Fast Symmetric Demons algorithm. Dose was accumulated on the fourth image in each set using DIR via two different image pathways. The two accumulated doses on the fourth image were compared. The inverse consistency and transitivity errors in the DVFs were then reduced. The dose accumulation was repeated using the processed DVFs, the results of which were compared with the accumulated dose from the original DVFs. To evaluate the influence of the postprocessing technique on DVF accuracy, the original and processed DVF accuracy was evaluated on the lung 4DCT data on which anatomical landmarks had been identified by an expert. Results: Dose accumulation to the same image via different image pathways resulted in two different accumulated dose results. After the inverse consistency errors were reduced, the difference between the accumulated doses diminished. The difference was further reduced after reducing the transitivity errors. The postprocessing technique had minimal effect on the accuracy of the DVF for the lung 4DCT images. Conclusions: This study shows that inverse consistency and transitivity errors in DIR have a significant dosimetric effect in dose accumulation; Depending on the image pathway taken to accumulate the dose, different results may be obtained. A postprocessing technique that reduces inverse consistency and transitivity error is presented, which allows for consistent dose accumulation regardless of the image pathway followed.« less
Stochastic inversion of cross-borehole radar data from metalliferous vein detection
NASA Astrophysics Data System (ADS)
Zeng, Zhaofa; Huai, Nan; Li, Jing; Zhao, Xueyu; Liu, Cai; Hu, Yingsa; Zhang, Ling; Hu, Zuzhi; Yang, Hui
2017-12-01
In the exploration and evaluation of the metalliferous veins with a cross-borehole radar system, traditional linear inversion methods (least squares inversion, LSQR) only get indirect parameters (permittivity, resistivity, or velocity) to estimate the target structure. They cannot accurately reflect the geological parameters of the metalliferous veins’ media properties. In order to get the intrinsic geological parameters and internal distribution, in this paper, we build a metalliferous veins model based on the stochastic effective medium theory, and carry out stochastic inversion and parameter estimation based on the Monte Carlo sampling algorithm. Compared with conventional LSQR, the stochastic inversion can get higher resolution inversion permittivity and velocity of the target body. We can estimate more accurately the distribution characteristics of abnormality and target internal parameters. It provides a new research idea to evaluate the properties of complex target media.
Bidirectional Gender Face Aftereffects: Evidence Against Normative Facial Coding.
Cronin, Sophie L; Spence, Morgan L; Miller, Paul A; Arnold, Derek H
2017-02-01
Facial appearance can be altered, not just by restyling but also by sensory processes. Exposure to a female face can, for instance, make subsequent faces look more masculine than they would otherwise. Two explanations exist. According to one, exposure to a female face renormalizes face perception, making that female and all other faces look more masculine as a consequence-a unidirectional effect. According to that explanation, exposure to a male face would have the opposite unidirectional effect. Another suggestion is that face gender is subject to contrastive aftereffects. These should make some faces look more masculine than the adaptor and other faces more feminine-a bidirectional effect. Here, we show that face gender aftereffects are bidirectional, as predicted by the latter hypothesis. Images of real faces rated as more and less masculine than adaptors at baseline tended to look even more and less masculine than adaptors post adaptation. This suggests that, rather than mental representations of all faces being recalibrated to better reflect the prevailing statistics of the environment, mental operations exaggerate differences between successive faces, and this can impact facial gender perception.
The complex duration perception of emotional faces: effects of face direction.
Kliegl, Katrin M; Limbrecht-Ecklundt, Kerstin; Dürr, Lea; Traue, Harald C; Huckauf, Anke
2015-01-01
The perceived duration of emotional face stimuli strongly depends on the expressed emotion. But, emotional faces also differ regarding a number of other features like gaze, face direction, or sex. Usually, these features have been controlled by only using pictures of female models with straight gaze and face direction. Doi and Shinohara (2009) reported that an overestimation of angry faces could only be found when the model's gaze was oriented toward the observer. We aimed at replicating this effect for face direction. Moreover, we explored the effect of face direction on the duration perception sad faces. Controlling for the sex of the face model and the participant, female and male participants rated the duration of neutral, angry, and sad face stimuli of both sexes photographed from different perspectives in a bisection task. In line with current findings, we report a significant overestimation of angry compared to neutral face stimuli that was modulated by face direction. Moreover, the perceived duration of sad face stimuli did not differ from that of neutral faces and was not influenced by face direction. Furthermore, we found that faces of the opposite sex appeared to last longer than those of the same sex. This outcome is discussed with regards to stimulus parameters like the induced arousal, social relevance, and an evolutionary context.
Multiple Fan-Beam Optical Tomography: Modelling Techniques
Rahim, Ruzairi Abdul; Chen, Leong Lai; San, Chan Kok; Rahiman, Mohd Hafiz Fazalul; Fea, Pang Jon
2009-01-01
This paper explains in detail the solution to the forward and inverse problem faced in this research. In the forward problem section, the projection geometry and the sensor modelling are discussed. The dimensions, distributions and arrangements of the optical fibre sensors are determined based on the real hardware constructed and these are explained in the projection geometry section. The general idea in sensor modelling is to simulate an artificial environment, but with similar system properties, to predict the actual sensor values for various flow models in the hardware system. The sensitivity maps produced from the solution of the forward problems are important in reconstructing the tomographic image. PMID:22291523
Damage identification using inverse methods.
Friswell, Michael I
2007-02-15
This paper gives an overview of the use of inverse methods in damage detection and location, using measured vibration data. Inverse problems require the use of a model and the identification of uncertain parameters of this model. Damage is often local in nature and although the effect of the loss of stiffness may require only a small number of parameters, the lack of knowledge of the location means that a large number of candidate parameters must be included. This paper discusses a number of problems that exist with this approach to health monitoring, including modelling error, environmental effects, damage localization and regularization.
Inverse relaxation effect of azo-dye molecules: The role of the film anisotropy
NASA Astrophysics Data System (ADS)
Sehnem, A. L.; Faita, F. L.; Cabrera, F. C.; Job, A. E.; Bechtold, I. H.
2013-11-01
We investigated the effect generally treated in the literature as inverse relaxation, which is related to an increase in the birefringence of azopolymer films after the inscription laser is turned off. The results demonstrate that films prepared with the casting method on anisotropic substrates induce a preferential organization of the polymeric chains. Inverse relaxation is evidenced only when the photo-alignment of the azo groups is induced parallel to the orientation of the polymeric chains. Thus, it is possible to enhance the optical storage in these systems with appropriate alignment methods.
ERIC Educational Resources Information Center
Cleary, Laura; Looney, Kathy; Brady, Nuala; Fitzgerald, Michael
2014-01-01
The "body inversion effect" refers to superior recognition of upright than inverted images of the human body and indicates typical configural processing. Previous research by Reed et al. using static images of the human body shows that people with autism fail to demonstrate this effect. Using a novel task in which adults, adolescents…
Modulation of the composite face effect by unintended emotion cues.
Gray, Katie L H; Murphy, Jennifer; Marsh, Jade E; Cook, Richard
2017-04-01
When upper and lower regions from different emotionless faces are aligned to form a facial composite, observers 'fuse' the two halves together, perceptually. The illusory distortion induced by task-irrelevant ('distractor') halves hinders participants' judgements about task-relevant ('target') halves. This composite-face effect reveals a tendency to integrate feature information from disparate regions of intact upright faces, consistent with theories of holistic face processing. However, observers frequently perceive emotion in ostensibly neutral faces, contrary to the intentions of experimenters. This study sought to determine whether this 'perceived emotion' influences the composite-face effect. In our first experiment, we confirmed that the composite effect grows stronger as the strength of distractor emotion increased. Critically, effects of distractor emotion were induced by weak emotion intensities, and were incidental insofar as emotion cues hindered image matching, not emotion labelling per se . In Experiment 2, we found a correlation between the presence of perceived emotion in a set of ostensibly neutral distractor regions sourced from commonly used face databases, and the strength of illusory distortion they induced. In Experiment 3, participants completed a sequential matching composite task in which half of the distractor regions were rated high and low for perceived emotion, respectively. Significantly stronger composite effects were induced by the high-emotion distractor halves. These convergent results suggest that perceived emotion increases the strength of the composite-face effect induced by supposedly emotionless faces. These findings have important implications for the study of holistic face processing in typical and atypical populations.
Effects of crustal layering on source parameter inversion from coseismic geodetic data
NASA Astrophysics Data System (ADS)
Amoruso, A.; Crescentini, L.; Fidani, C.
2004-10-01
We study the effect of a superficial layer overlying a half-space on the surface displacements caused by uniform slipping of a dip-slip normal rectangular fault. We compute static coseismic displacements using a 3-D analytical code for different characteristics of the layered medium, different fault geometries and different configurations of bench marks to simulate different kinds of geodetic data (GPS, Synthetic Aperture Radar, and levellings). We perform both joint and separate inversions of the three components of synthetic displacement without constraining fault parameters, apart from strike and rake, and using a non-linear global inversion technique under the assumption of homogeneous half-space. Differences between synthetic displacements computed in the presence of the superficial soft layer and in a homogeneous half-space do not show a simple regular behaviour, even if a few features can be identified. Consequently, also retrieved parameters of the homogeneous equivalent fault obtained by unconstrained inversion of surface displacements do not show a simple regular behaviour. We point out that the presence of a superficial layer may lead to misestimating several fault parameters both using joint and separate inversions of the three components of synthetic displacement and that the effects of the presence of the superficial layer can change whether all fault parameters are left free in the inversions or not. In the inversion of any kind of coseismic geodetic data, fault size and slip can be largely misestimated, but the product (fault length) × (fault width) × slip, which is proportional to the seismic moment for a given rigidity modulus, is often well determined (within a few per cent). Because inversion of coseismic geodetic data assuming a layered medium is impracticable, we suggest that only a case-to-case study involving some kind of recursive determination of fault parameters through data correction seems to give the proper approach when layering is important.
Empirical data on 220 families with de novo or inherited paracentric inversions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eyre, J.; McConkie-Rosell, A.; Tripp, T.
Six new cases of paracentric inversions (3 detected prenatally) are presented and added to an expanding database of paracentric inversions. Three inversions were associated with an abnormal phenotype and detected postnatally: inv(2)(p21p23), inv(13)(q14q34), and inv(18)(q12.3q23). The present database of paracentric inversions includes 220 families reported. All chromosomes were involved except chromosome 20. The most frequent inversions were found on chromosomes 1, 3, 7, 11, and 14. 48 index cases had an abnormal phenotype not explainable by other causes such as additional chromosome abnormalities. Of these, 12 were de novo and 36 familial. By contrast, of the 122 index cases withmore » normal phenotype, there were 8 de novo and 87 familial cases (rest unknown). Ascertainment bias probably accounts for some of the abnormal inherited inversions cases. Maternally inherited inversions were more frequent than paternally inherited (72 versus 55). Inversions were found in males more than females (ratio of 4 to 3). There were some paracentric inversions that appear to be less involved with abnormal phenotypes (e.g., 11q21q23) than other inversions (e.g., inv X and Turner syndrome). An interesting observation which warrants further investigation is the excess number of fetal losses and karyotypically abnormal progeny in paracentric inversion carriers. The presence of additional karyotypic abnormalities in the children might be explainable by interchromosomal effects and chromosome position changes in the nucleus. Genetic counseling for paracentric inversions should take into consideration mode of ascertainment, inheritance, and chromosome involved. We solicit other cases of paracentric inversions to make this database more useful in counseling patients and families.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Djara, V.; Cherkaoui, K.; Negara, M. A.
2015-11-28
An alternative multi-frequency inversion-charge pumping (MFICP) technique was developed to directly separate the inversion charge density (N{sub inv}) from the trapped charge density in high-k/InGaAs metal-oxide-semiconductor field-effect transistors (MOSFETs). This approach relies on the fitting of the frequency response of border traps, obtained from inversion-charge pumping measurements performed over a wide range of frequencies at room temperature on a single MOSFET, using a modified charge trapping model. The obtained model yielded the capture time constant and density of border traps located at energy levels aligned with the InGaAs conduction band. Moreover, the combination of MFICP and pulsed I{sub d}-V{sub g}more » measurements enabled an accurate effective mobility vs N{sub inv} extraction and analysis. The data obtained using the MFICP approach are consistent with the most recent reports on high-k/InGaAs.« less
Using a pseudo-dynamic source inversion approach to improve earthquake source imaging
NASA Astrophysics Data System (ADS)
Zhang, Y.; Song, S. G.; Dalguer, L. A.; Clinton, J. F.
2014-12-01
Imaging a high-resolution spatio-temporal slip distribution of an earthquake rupture is a core research goal in seismology. In general we expect to obtain a higher quality source image by improving the observational input data (e.g. using more higher quality near-source stations). However, recent studies show that increasing the surface station density alone does not significantly improve source inversion results (Custodio et al. 2005; Zhang et al. 2014). We introduce correlation structures between the kinematic source parameters: slip, rupture velocity, and peak slip velocity (Song et al. 2009; Song and Dalguer 2013) in the non-linear source inversion. The correlation structures are physical constraints derived from rupture dynamics that effectively regularize the model space and may improve source imaging. We name this approach pseudo-dynamic source inversion. We investigate the effectiveness of this pseudo-dynamic source inversion method by inverting low frequency velocity waveforms from a synthetic dynamic rupture model of a buried vertical strike-slip event (Mw 6.5) in a homogeneous half space. In the inversion, we use a genetic algorithm in a Bayesian framework (Moneli et al. 2008), and a dynamically consistent regularized Yoffe function (Tinti, et al. 2005) was used for a single-window slip velocity function. We search for local rupture velocity directly in the inversion, and calculate the rupture time using a ray-tracing technique. We implement both auto- and cross-correlation of slip, rupture velocity, and peak slip velocity in the prior distribution. Our results suggest that kinematic source model estimates capture the major features of the target dynamic model. The estimated rupture velocity closely matches the target distribution from the dynamic rupture model, and the derived rupture time is smoother than the one we searched directly. By implementing both auto- and cross-correlation of kinematic source parameters, in comparison to traditional smoothing constraints, we are in effect regularizing the model space in a more physics-based manner without loosing resolution of the source image. Further investigation is needed to tune the related parameters of pseudo-dynamic source inversion and relative weighting between the prior and the likelihood function in the Bayesian inversion.
Hadj-Bouziane, Fadila; Liu, Ning; Bell, Andrew H.; Gothard, Katalin M.; Luh, Wen-Ming; Tootell, Roger B. H.; Murray, Elisabeth A.; Ungerleider, Leslie G.
2012-01-01
We previously showed that facial expressions modulate functional MRI activity in the face-processing regions of the macaque monkey’s amygdala and inferior temporal (IT) cortex. Specifically, we showed that faces expressing emotion yield greater activation than neutral faces; we term this difference the “valence effect.” We hypothesized that amygdala lesions would disrupt the valence effect by eliminating the modulatory feedback from the amygdala to the IT cortex. We compared the valence effects within the IT cortex in monkeys with excitotoxic amygdala lesions (n = 3) with those in intact control animals (n = 3) using contrast agent-based functional MRI at 3 T. Images of four distinct monkey facial expressions—neutral, aggressive (open mouth threat), fearful (fear grin), and appeasing (lip smack)—were presented to the subjects in a blocked design. Our results showed that in monkeys with amygdala lesions the valence effects were strongly disrupted within the IT cortex, whereas face responsivity (neutral faces > scrambled faces) and face selectivity (neutral faces > non-face objects) were unaffected. Furthermore, sparing of the anterior amygdala led to intact valence effects in the anterior IT cortex (which included the anterior face-selective regions), whereas sparing of the posterior amygdala led to intact valence effects in the posterior IT cortex (which included the posterior face-selective regions). Overall, our data demonstrate that the feedback projections from the amygdala to the IT cortex mediate the valence effect found there. Moreover, these modulatory effects are consistent with an anterior-to-posterior gradient of projections, as suggested by classical tracer studies. PMID:23184972
Ligon, D A; Gillespie, J B; Pellegrino, P
2000-08-20
The feasibility of using a generalized stochastic inversion methodology to estimate aerosol size distributions accurately by use of spectral extinction, backscatter data, or both is examined. The stochastic method used, inverse Monte Carlo (IMC), is verified with both simulated and experimental data from aerosols composed of spherical dielectrics with a known refractive index. Various levels of noise are superimposed on the data such that the effect of noise on the stability and results of inversion can be determined. Computational results show that the application of the IMC technique to inversion of spectral extinction or backscatter data or both can produce good estimates of aerosol size distributions. Specifically, for inversions for which both spectral extinction and backscatter data are used, the IMC technique was extremely accurate in determining particle size distributions well outside the wavelength range. Also, the IMC inversion results proved to be stable and accurate even when the data had significant noise, with a signal-to-noise ratio of 3.
Chong, Jessica X; McMillin, Margaret J; Shively, Kathryn M; Beck, Anita E; Marvin, Colby T; Armenteros, Jose R; Buckingham, Kati J; Nkinsi, Naomi T; Boyle, Evan A; Berry, Margaret N; Bocian, Maureen; Foulds, Nicola; Uzielli, Maria Luisa Giovannucci; Haldeman-Englert, Chad; Hennekam, Raoul C M; Kaplan, Paige; Kline, Antonie D; Mercer, Catherine L; Nowaczyk, Malgorzata J M; Klein Wassink-Ruiter, Jolien S; McPherson, Elizabeth W; Moreno, Regina A; Scheuerle, Angela E; Shashi, Vandana; Stevens, Cathy A; Carey, John C; Monteil, Arnaud; Lory, Philippe; Tabor, Holly K; Smith, Joshua D; Shendure, Jay; Nickerson, Deborah A; Bamshad, Michael J
2015-03-05
Freeman-Sheldon syndrome, or distal arthrogryposis type 2A (DA2A), is an autosomal-dominant condition caused by mutations in MYH3 and characterized by multiple congenital contractures of the face and limbs and normal cognitive development. We identified a subset of five individuals who had been putatively diagnosed with "DA2A with severe neurological abnormalities" and for whom congenital contractures of the limbs and face, hypotonia, and global developmental delay had resulted in early death in three cases; this is a unique condition that we now refer to as CLIFAHDD syndrome. Exome sequencing identified missense mutations in the sodium leak channel, non-selective (NALCN) in four families affected by CLIFAHDD syndrome. We used molecular-inversion probes to screen for NALCN in a cohort of 202 distal arthrogryposis (DA)-affected individuals as well as concurrent exome sequencing of six other DA-affected individuals, thus revealing NALCN mutations in ten additional families with "atypical" forms of DA. All 14 mutations were missense variants predicted to alter amino acid residues in or near the S5 and S6 pore-forming segments of NALCN, highlighting the functional importance of these segments. In vitro functional studies demonstrated that NALCN alterations nearly abolished the expression of wild-type NALCN, suggesting that alterations that cause CLIFAHDD syndrome have a dominant-negative effect. In contrast, homozygosity for mutations in other regions of NALCN has been reported in three families affected by an autosomal-recessive condition characterized mainly by hypotonia and severe intellectual disability. Accordingly, mutations in NALCN can cause either a recessive or dominant condition characterized by varied though overlapping phenotypic features, perhaps based on the type of mutation and affected protein domain(s). Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.
Chen, F; He, B-C; Yan, L-J; Liu, F-P; Huang, J-F; Hu, Z-J; Lin, Z; Zheng, X-Y; Lin, L-S; Zhang, Z-F; Cai, L
2017-04-01
Epidemiological results on the association between tea consumption and oral cancer remain controversial. We aimed to evaluate the exact relationship between tea consumption and oral cancer in Chinese population. A large-scale case-control study was conducted on 586 oral cancer patients and 1024 controls frequency-matched by age and gender. Epidemiological data were collected through face-to-face interviews with a structure questionnaire. Unconditional logistic regression model was used to assess the effect of tea consumption on oral cancer stratified by smoking, alcohol drinking and demographics. Quantity of tea consumed (ml/day) was categorized into five subgroups based on quartiles and then its interactions was evaluated with tobacco smoking and alcohol drinking at each subgroup. Tea consumption showed an inverse association with oral cancer for non-smokers or non-alcohol drinkers (the odds ratios (ORs) were 0.610 (95% confidence interval (CI): 0.425-0.876) and 0.686 (95% CI: 0.503-0.934), respectively). For smokers or alcohol drinkers, decreased risk was only observed in those who consumed >800 ml/day. Furthermore, oolong tea consumption was associated with decreased risk of oral cancer in smokers or alcohol drinkers but not in non-smokers or non-alcohol drinkers. Tea consumption combined with smoking or/and alcohol drinking had a greater risk than tea consumption alone, but the risk was roughly reduced from zero to Q4 (>800 ml/day). Additionally, when stratified by demographics, the protective effect of tea was especially evident in females, urban residents, normal body mass index population (18.5-23.9), farmers, office workers and those aged <60 years. Tea consumption protects against oral cancer in non-smokers or non-alcohol drinkers, but this effect may be obscured in smokers or alcohol drinkers. Additionally, demographics may modify the association between tea consumption and oral cancer.
Singh, Leher; Loh, Darrell; Xiao, Naiqi G.
2017-01-01
Perceptual narrowing is a highly significant development associated with the first year of life. It conventionally refers to an orientation toward nativeness whereby infant's perceptual sensitivities begin to align with the phonetic properties of their native environment. Nativeness effects, such as perceptual narrowing, have been observed in several domains, most notably, in face discrimination within other-race faces and speech discrimination of non-native phonemes. Thus, far, nativeness effects in the face and speech perception have been theoretically linked, but have mostly been investigated independently. An important caveat to nativeness effects is that diversifying experiences, such as bilingualism or multiracial exposure, can lead to a reduction or postponement in attunement to the native environment. The present study was designed to investigate whether bilingualism influences nativeness effects in phonetic and face perception. Eleven-month-old monolingual and bilingual infants were tested on their abilities to discriminate native and non-native speech contrasts as well as own-race and other-race face contrasts. While monolingual infants demonstrated nativeness effects in face and speech perception, bilingual infants demonstrated nativeness effects in the face perception but demonstrated flexibility in speech perception. Results support domain-specific effects of bilingual experience on nativeness effects. PMID:28955278
Angle dependence in slow photon photocatalysis using TiO2 inverse opals
NASA Astrophysics Data System (ADS)
Curti, Mariano; Zvitco, Gonzalo; Grela, María Alejandra; Mendive, Cecilia B.
2018-03-01
The slow photon effect was studied by means of the photocatalytic degradation of stearic acid over TiO2 inverse opals. The comparison of the degradation rates over inverse opals with those obtained over disordered structures at different irradiation angles showed that the irradiation at the blue edge of the stopband leads to the activation of the effect, evidenced by an improvement factor of 1.8 ± 0.6 in the reaction rate for irradiation at 40°. The rigorous coupled-wave analysis (RCWA) method was employed to confirm the source of the enhancement; simulated spectra showed an enhancement in the absorption of the TiO2 matrix that composes the inverse opal at a 40° irradiation angle, owing to an appropriate position of the stopband in relation to the absorption onset of TiO2.
NASA Astrophysics Data System (ADS)
Monnier, S.; Lumley, D. E.; Kamei, R.; Goncharov, A.; Shragge, J. C.
2016-12-01
Ocean Bottom Seismic datasets have become increasingly used in recent years to develop high-resolution, wavelength-scale P-wave velocity models of the lithosphere from waveform inversion, due to their recording of long-offset transmitted phases. New OBS surveys evolve towards novel acquisition geometries involving longer offsets (several hundreds of km), broader frequency content (1-100 Hz), while receiver sampling often remains sparse (several km). Therefore, it is critical to assess the effects of such geometries on the eventual success and resolution of waveform inversion velocity models. In this study, we investigate the feasibility of waveform inversion on the Bart 2D OBS profile acquired offshore Western Australia, to investigate regional crustal and Moho structures. The dataset features 14 broadband seismometers (0.01-100 Hz) from AuScope's national OBS fleet, offsets in excess of 280 km, and a sparse receiver sampling (18 km). We perform our analysis in four stages: (1) field data analysis, (2) 2D P-wave velocity model building, synthetic data (3) modelling, and (4) waveform inversion. Data exploration shows high-quality active-source signal down to 2Hz, and usable first arrivals to offsets greater than 100 km. The background velocity model is constructed by combining crustal and Moho information in continental reference models (e.g., AuSREM, AusMoho). These low-resolution studies suggest a crustal thickness of 20-25 km along our seismic line and constitute a starting point for synthetic modelling and inversion. We perform synthetic 2D time-domain modelling to: (1) evaluate the misfit between synthetic and field data within the usable frequency band (2-10 Hz); (2) validate our velocity model; and (3) observe the effects of sparse OBS interval on data quality. Finally, we apply 2D acoustic frequency-domain waveform inversion to the synthetic data to generate velocity model updates. The inverted model is compared to the reference model to investigate the improved crustal resolution and Moho boundary delineation that could be realized using waveform inversion, and to evaluate the effects of the acquisition parameters. The inversion strategies developed through the synthetic tests will help the subsequent inversion of sparse, long-offset OBS field data.
A Comparison of Two Native American Navigator Formats: Face-to-Face and Telephone
Dignan, Mark B.; Burhansstipanov, Linda; Hariton, Judy; Harjo, Lisa; Rattler, Jerri; Lee, Rose; Mason, Mondi
2012-01-01
The study was designed to test the relative effectiveness of a Navigator intervention delivered face-to-face or by telephone to urban Native American women. The effectiveness of the intervention was evaluated using a design that included a pretest, random assignment to face-to-face or telephone group, and posttest. The Social Cognitive Theory-based intervention was a tailored education program developed to address individual risk factors for breast cancer. At posttest, self-reported mammograms in the past year increased from 29% to 41.3% in the telephone group and from 34.4%: to 45.2% in the face-to-face group. There was no difference in change from pretest to posttest between the telephone and face-to-face groups. Navigators can be effective in increasing adherence to recommendations for screening mammography among urban American Indian women. PMID:16327748
Chen, Kuan-Ting; Fan, Jun Wei; Chang, Shu-Tong; Lin, Chung-Yi
2015-03-01
In this paper, the subband structure and effective mass of an Si-based alloy inversion layer in a PMOSFET are studied theoretically. The strain condition considered in our calculations is the intrinsic strain resulting from growth of the silicon-carbon alloy on a (001) Si substrate and mechanical uniaxial stress. The quantum confinement effect resulting from the vertically effective electric field was incorporated into the k · p calculation. The distinct effective mass, such as the quantization effective mass and the density-of-states (DOS) effective mass, as well as the subband structure of the silicon-carbon alloy inversion layer for a PMOSFET under substrate strain and various effective electric field strengths, were all investigated. Ore results show that subband structure of relaxed silicon-carbon alloys with low carbon content are almost the same as silicon. We find that an external stress applied parallel to the channel direction can efficiently reduce the effective mass along the channel direction, thus producing hole mobility enhancement.
ERIC Educational Resources Information Center
Hung, Yen-Chu
2011-01-01
This study investigates the different effects of web-based and face-to-face discussion on computer engineering majors' performance using the Karnaugh map in digital logic design. Pretest and posttest scores for two treatment groups (web-based discussion and face-to-face discussion) and a control group were compared and subjected to covariance…
Deficits of unconscious emotional processing in patients with major depression: An ERP study.
Zhang, Dandan; He, Zhenhong; Chen, Yuming; Wei, Zhaoguo
2016-07-15
Major depressive disorder (MDD) is associated with behavioral and neurobiological evidences of negative bias in unconscious emotional processing. However, little is known about the time course of this deficit. The current study aimed to explore the unconscious processing of emotional facial expressions in MDD patients by means of event-related potentials (ERPs). The ERP responses to subliminally presented happy/neutral/sad faces were recorded in 26 medication-free patients and 26 healthy controls in a backward masking task. Three ERP components were compared between patients and controls. Detection accuracy was at chance level for both groups, suggesting that the process was performed in the absence of conscious awareness of the emotional stimuli. Robust emotion×group interactions were observed in P1, N170 and P3. Compared with the neutral faces, 1) the patients showed larger P1 for sad and smaller P1 for happy faces; however, the controls showed a completely inverse P1 pattern; 2) the controls exhibited larger N170 in the happy but not in the sad trials, whereas patients had comparable larger N170 amplitudes in sad and happy trials; 3) although both groups exhibited larger P3 for emotional faces, the patients showed a priority for sad trials while the controls showed a priority for happy trials. Our data suggested that negative processing bias exists on the unconscious level in individuals with MDD. The ERP measures indicated that the unconscious emotional processing in MDD patients has a time course of three-stage deflection. Copyright © 2016 Elsevier B.V. All rights reserved.
One lens optical correlation: application to face recognition.
Jridi, Maher; Napoléon, Thibault; Alfalou, Ayman
2018-03-20
Despite its extensive use, the traditional 4f Vander Lugt Correlator optical setup can be further simplified. We propose a lightweight correlation scheme where the decision is taken in the Fourier plane. For this purpose, the Fourier plane is adapted and used as a decision plane. Then, the offline phase and the decision metric are re-examined in order to keep a reasonable recognition rate. The benefits of the proposed approach are numerous: (1) it overcomes the constraints related to the use of a second lens; (2) the optical correlation setup is simplified; (3) the multiplication with the correlation filter can be done digitally, which offers a higher adaptability according to the application. Moreover, the digital counterpart of the correlation scheme is lightened since with the proposed scheme we get rid of the inverse Fourier transform (IFT) calculation (i.e., decision directly in the Fourier domain without resorting to IFT). To assess the performance of the proposed approach, an insight into digital hardware resources saving is provided. The proposed method involves nearly 100 times fewer arithmetic operators. Moreover, from experimental results in the context of face verification-based correlation, we demonstrate that the proposed scheme provides comparable or better accuracy than the traditional method. One interesting feature of the proposed scheme is that it could greatly outperform the traditional scheme for face identification application in terms of sensitivity to face orientation. The proposed method is found to be digital/optical implementation-friendly, which facilitates its integration on a very broad range of scenarios.