Acute Neuroinflammation Impairs Context Discrimination Memory and Disrupts Pattern Separation Processes in Hippocampus

PubMed Central

Czerniawski, Jennifer

2014-01-01

Although it is known that immune system activation can impair cognition, no study to date has linked cognitive deficits during acute neuroinflammation to dysregulation of task-relevant neuronal ensemble activity. Here, we assessed both neural circuit activity and context discrimination memory retrieval, in a within-subjects design, of male rats given systemic administration of saline or lipopolysaccharide (LPS). Rats were exposed over several days to two similar contexts: one of which was paired with weak foot shock and the other was not. After reaching criteria for discriminative freezing, rats were given systemic LPS or saline injection and tested for retrieval of context discrimination 6 h later. Importantly, LPS administration produced an acute neuroinflammatory response in dorsal hippocampus at this time (as assessed by elevation of proinflammatory cytokine mRNA levels) and abolished retrieval of the previously acquired discrimination. The impact of neuroinflammation on hippocampal CA3 and CA1 neural circuit activity was assessed using the Arc/Homer1a cellular analysis of temporal activity by fluorescence in situ hybridization imaging method. Whereas the saline-treated subjects discriminated and had low overlap of hippocampal ensembles activated in the two contexts, LPS-treated subjects did not discriminate and had greater ensemble overlap (i.e., reduced orthogonalization). Additionally, retrieval of standard contextual fear conditioning, which does not require context discrimination, was not affected by pretesting LPS administration. Together, the behavioral and circuit analyses data provide compelling evidence that LPS administration impairs context discrimination memory by disrupting cellular pattern separation processes within the hippocampus, thus linking acute neuroinflammation to disruption of specific neural circuit functions and cognitive impairment. PMID:25209285

The co-development of looking dynamics and discrimination performance

PubMed Central

Perone, Sammy; Spencer, John P.

2015-01-01

The study of looking dynamics and discrimination form the backbone of developmental science and are central processes in theories of infant cognition. Looking dynamics and discrimination change dramatically across the first year of life. Surprisingly, developmental changes in looking and discrimination have not been studied together. Recent simulations of a dynamic neural field (DNF) model of infant looking and memory suggest that looking and discrimination do change together over development and arise from a single neurodevelopmental mechanism. We probe this claim by measuring looking dynamics and discrimination along continuous, metrically organized dimensions in 5-, 7, and 10-month-old infants (N = 119). The results showed that looking dynamics and discrimination changed together over development and are linked within individuals. Quantitative simulations of a DNF model provide insights into the processes that underlie developmental change in looking dynamics and discrimination. Simulation results support the view that these changes might arise from a single neurodevelopmental mechanism. PMID:23957821

Configurations of the interoceptive discriminative stimulus effects of ethanol and nicotine with two different exteroceptive contexts in rats: Extinction & recovery.

PubMed

Troisi, Joseph R; Craig, Elizabeth M

2015-06-01

Interoceptive states interact with exteroceptive contexts in modulating operant behavior, which is maintained by its consequences. Evaluating discriminative stimulus control by overlapping interoceptive and exteroceptive configurations (gestalts) and the contribution of each modality may be clinically important for understanding aspects of relapsing behavior (e.g., drug abuse). With rats, the current investigation used a completely counterbalanced one-manipulandum operant drug discrimination procedure that established discriminative stimulus control between nicotine (0.3mg/kg) in one exteroceptive context and EtOH (1.0g/kg) in a differing exteroceptive context. One combined interoceptive-exteroceptive condition occasioned sessions of food reinforcement (S(D)) and the other counterbalanced condition occasioned sessions of non-reinforcement (S(Δ)). Each stimulus modality contributed to discriminative control, but to lesser extents than the combined intero-exteroceptive compound configurations (Experiments 1 & 2). In Experiment 1, responding was extinguished in the interoceptive stimulus conditions alone in a neutral exteroceptive context, but then renewed by reconfiguring the drugs with the exteroceptive contexts, and reversed in the opposing exteroceptive contexts. In Experiment 2, responding was extinguished in the interoceptive and exteroceptive contexts separately. Reconfiguration of the full intero-exteroceptive compound configurations did not promote recovery. These results suggest that interoceptive and exteroceptive discriminative control can be methodologically configured in modulating operant behavior during acquisition, extinction, and recovery of behavior; however, configuring interoceptive and exteroceptive discriminative stimuli do not appear to function as unique cues that differ from each stimulus modality alone. Clinical implications are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

Contextualizing acculturative stress among Latino immigrants in the United States: a systematic review.

PubMed

Bekteshi, Venera; Kang, Sung-Wan

2018-05-23

This systematic review of the literature informed of (a) the relationship between acculturation and acculturative stress, (b) examined the determinants of acculturative stress among Latino immigrants in the U.S., and (c) provided a conceptual framework that can be used to specify the interactive effect of various factors on acculturative stress. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), this review synthesized the results of thirty studies published between 2000 and 2015 that investigated the influence of several socio-demographic and cultural contexts on acculturative stress among Latino immigrants categorized using Family Stress Management (FSM) theory as a framework. Studied highlighted several protectors from and risks to acculturative stress. Historical context protective factors included having a choice over the decision to migrate and social support; risks included discrimination, family left abroad, and fear of deportation. Economic context protective factors included higher income. The development context protective factors included English skills, years in the U.S., and being married; risks included being female. Cultural context protective factors included being culturally competent and acculturation; risks included family-cultural conflict and ethnic enclave pressures. Internal context protectors included post-immigration religious coping, church attendance, and family values. The results highlighted incorporating cultural aspects (i.e. family values and social support) in mental health practice with Latino immigrants. A less stressful integration experience can be achieved if age-related stressors and experiences of discrimination are acknowledged and the need for social support and harmonious family dynamics was prioritized in service plans.

Context modulation of learned attention deployment.

PubMed

Uengoer, Metin; Pearce, John M; Lachnit, Harald; Koenig, Stephan

2018-03-01

In three experiments, we investigated the contextual control of attention in human discrimination learning. In each experiment, participants initially received discrimination training in which the cues from Dimension A were relevant in Context 1 but irrelevant in Context 2, whereas the cues from Dimension B were irrelevant in Context 1 but relevant in Context 2. In Experiment 1, the same cues from each dimension were used in Contexts 1 and 2, whereas in Experiments 2 and 3, the cues from each dimension were changed across contexts. In each experiment, participants were subsequently shifted to a transfer discrimination involving novel cues from either dimension, to assess the contextual control of attention. In Experiment 1, measures of eye gaze during the transfer discrimination revealed that Dimension A received more attention than Dimension B in Context 1, whereas the reverse occurred in Context 2. Corresponding results indicating the contextual control of attention were found in Experiments 2 and 3, in which we used the speed of learning (associability) as an indirect marker of learned attentional changes. Implications of our results for current theories of learning and attention are discussed.

Context affects nestmate recognition errors in honey bees and stingless bees.

PubMed

Couvillon, Margaret J; Segers, Francisca H I D; Cooper-Bowman, Roseanne; Truslove, Gemma; Nascimento, Daniela L; Nascimento, Fabio S; Ratnieks, Francis L W

2013-08-15

Nestmate recognition studies, where a discriminator first recognises and then behaviourally discriminates (accepts/rejects) another individual, have used a variety of methodologies and contexts. This is potentially problematic because recognition errors in discrimination behaviour are predicted to be context-dependent. Here we compare the recognition decisions (accept/reject) of discriminators in two eusocial bees, Apis mellifera and Tetragonisca angustula, under different contexts. These contexts include natural guards at the hive entrance (control); natural guards held in plastic test arenas away from the hive entrance that vary either in the presence or absence of colony odour or the presence or absence of an additional nestmate discriminator; and, for the honey bee, the inside of the nest. For both honey bee and stingless bee guards, total recognition errors of behavioural discrimination made by guards (% nestmates rejected + % non-nestmates accepted) are much lower at the colony entrance (honey bee: 30.9%; stingless bee: 33.3%) than in the test arenas (honey bee: 60-86%; stingless bee: 61-81%; P<0.001 for both). Within the test arenas, the presence of colony odour specifically reduced the total recognition errors in honey bees, although this reduction still fell short of bringing error levels down to what was found at the colony entrance. Lastly, in honey bees, the data show that the in-nest collective behavioural discrimination by ca. 30 workers that contact an intruder is insufficient to achieve error-free recognition and is not as effective as the discrimination by guards at the entrance. Overall, these data demonstrate that context is a significant factor in a discriminators' ability to make appropriate recognition decisions, and should be considered when designing recognition study methodologies.

Discrimination and Depressive Symptoms Among Latina/o Adolescents of Immigrant Parents.

PubMed

Lopez, William D; LeBrón, Alana M W; Graham, Louis F; Grogan-Kaylor, Andrew

2016-01-01

Discrimination is associated with negative mental health outcomes for Latina/o adolescents. While Latino/a adolescents experience discrimination from a number of sources and across contexts, little research considers how the source of discrimination and the context in which it occurs affect mental health outcomes among Latina/o children of immigrants. We examined the association between source-specific discrimination, racial or ethnic background of the source, and school ethnic context with depressive symptoms for Latina/o adolescents of immigrant parents. Using multilevel linear regression with time-varying covariates, we regressed depressive symptoms on source-specific discrimination, racial or ethnic background of the source of discrimination, and school percent Latina/o. Discrimination from teachers (β = 0.06, p < .05), students (β = 0.05, p < .05), Cubans (β = 0.19, p < .001), and Latinas/os (β = 0.19, p < .001) were positively associated with depressive symptoms. These associations were not moderated by school percent Latina/o. The findings indicate a need to reduce discrimination to improve Latina/o adolescents' mental health. © The Author(s) 2016.

The Co-Development of Looking Dynamics and Discrimination Performance

ERIC Educational Resources Information Center

Perone, Sammy; Spencer, John P.

2014-01-01

The study of looking dynamics and discrimination form the backbone of developmental science and are central processes in theories of infant cognition. Looking dynamics and discrimination change dramatically across the 1st year of life. Surprisingly, developmental changes in looking and discrimination have not been studied together. Recent…

Mechanisms of renewal after the extinction of discriminated operant behavior.

PubMed

Todd, Travis P; Vurbic, Drina; Bouton, Mark E

2014-07-01

Three experiments demonstrated, and examined the mechanisms that underlie, the renewal of extinguished discriminated operant behavior. In Experiment 1, rats were trained to perform 1 response (lever press or chain pull) in the presence of one discriminative stimulus (S; light or tone) in Context A, and to perform the other response in the presence of the other S in Context B. Next, each of the original S/response combinations was extinguished in the alternate context. When the S/response combinations were tested back in the context in which they had been trained, responding in the presence of S returned (an ABA renewal effect was observed). This renewal could not be due to differential context-reinforcer associations, suggesting instead that the extinction context inhibits either the response and/or the effectiveness of the S. Consistent with the latter mechanism, in Experiment 2, ABA renewal was still observed when both the extinction and renewal contexts inhibited the same response. However, in Experiment 3, previous extinction of the response in the renewing context (occasioned by a different S) reduced AAB renewal more than did extinction of the different response. Taken together, the results suggest at least 2 mechanisms of renewal after instrumental extinction. First, extinction performance is at least partly controlled by a direct inhibitory association that is formed between the context and the response. Second, in the discriminated operant procedure, extinction performance can sometimes be partly controlled by a reduction in the effectiveness of the S in the extinction context. Renewal of discriminated operant behavior can be produced by a release from either of these forms of inhibition.

The effects of acute nicotine on contextual safety discrimination.

PubMed

Kutlu, Munir G; Oliver, Chicora; Gould, Thomas J

2014-11-01

Anxiety disorders, such as post-traumatic stress disorder (PTSD), may be related to an inability to distinguish safe versus threatening environments and to extinguish fear memories. Given the high rate of cigarette smoking in patients with PTSD, as well as the recent finding that an acute dose of nicotine impairs extinction of contextual fear memory, we conducted a series of experiments to investigate the effect of acute nicotine in an animal model of contextual safety discrimination. Following saline or nicotine (at 0.0275, 0.045, 0.09 and 0.18 mg/kg) administration, C57BL/6J mice were trained in a contextual discrimination paradigm, in which the subjects received presentations of conditioned stimuli (CS) that co-terminated with a foot-shock in one context (context A (CXA)) and only CS presentations without foot-shock in a different context (context B (CXB)). Therefore, CXA was designated as the 'dangerous context', whereas CXB was designated as the 'safe context'. Our results suggested that saline-treated animals showed a strong discrimination between dangerous and safe contexts, while acute nicotine dose-dependently impaired contextual safety discrimination (Experiment 1). Furthermore, our results demonstrate that nicotine-induced impairment of contextual safety discrimination learning was not a result of increased generalized freezing (Experiment 2) or contingent on the common CS presentations in both contexts (Experiment 3). Finally, our results show that increasing the temporal gap between CXA and CXB during training abolished the impairing effects of nicotine (Experiment 4). The findings of this study may help link nicotine exposure to the safety learning deficits seen in anxiety disorder and PTSD patients. © The Author(s) 2014.

COMPLEX CONDITIONAL CONTROL BY PIGEONS IN A CONTINUOUS VIRTUAL ENVIRONMENT

PubMed Central

Qadri, Muhammad A. J.; Reid, Sean; Cook, Robert G.

2016-01-01

We tested two pigeons in a continuously streaming digital environment. Using animation software that constantly presented a dynamic, three-dimensional (3D) environment, the animals were tested with a conditional object identification task. The correct object at a given time depended on the virtual context currently streaming in front of the pigeon. Pigeons were required to accurately peck correct target objects in the environment for food reward, while suppressing any pecks to intermixed distractor objects which delayed the next object’s presentation. Experiment 1 established that the pigeons’ discrimination of two objects could be controlled by the surface material of the digital terrain. Experiment 2 established that the pigeons’ discrimination of four objects could be conjunctively controlled by both the surface material and topography of the streaming environment. These experiments indicate that pigeons can simultaneously process and use at least two context cues from a streaming environment to control their identification behavior of passing objects. These results add to the promise of testing interactive digital environments with animals to advance our understanding of cognition and behavior. PMID:26781058

Perception of coarticulated tones by non-native listeners

NASA Astrophysics Data System (ADS)

Bent, Tessa

2005-04-01

Mandarin lexical tones vary in their acoustic realization depending on the surrounding context. Native listeners compensate for this tonal coarticulation when identifying tones in context. This study investigated how native English listeners handle tonal coarticulation by testing native English and Mandarin listeners discrimination of the four Mandarin lexical tones in tri-syllabic sequences in which the middle tone varied while the first and last tones were held constant. Three different such frames were tested. As expected, Mandarin listeners discriminated all pairs in all contexts with a high degree of accuracy. English listeners exhibited poorer discrimination than Mandarin listeners and their discrimination accuracy showed a high degree of context dependency. In addition to assessing accuracy, reactions times to correctly discriminated different trials were entered into a multidimensional scaling analysis. For both listener groups, the arrangement of tones in perceptual space varied depending on the surrounding context suggesting that listeners attend to different acoustic attributes of the target tone depending on the surrounding tones. These results demonstrate the importance for models of cross-language speech perception of including contextual variation when characterizing the perception of non-native prosodic categories. [Work supported by NIH/NIDCD

Top-down modulation of auditory processing: effects of sound context, musical expertise and attentional focus.

PubMed

Tervaniemi, M; Kruck, S; De Baene, W; Schröger, E; Alter, K; Friederici, A D

2009-10-01

By recording auditory electrical brain potentials, we investigated whether the basic sound parameters (frequency, duration and intensity) are differentially encoded among speech vs. music sounds by musicians and non-musicians during different attentional demands. To this end, a pseudoword and an instrumental sound of comparable frequency and duration were presented. The accuracy of neural discrimination was tested by manipulations of frequency, duration and intensity. Additionally, the subjects' attentional focus was manipulated by instructions to ignore the sounds while watching a silent movie or to attentively discriminate the different sounds. In both musicians and non-musicians, the pre-attentively evoked mismatch negativity (MMN) component was larger to slight changes in music than in speech sounds. The MMN was also larger to intensity changes in music sounds and to duration changes in speech sounds. During attentional listening, all subjects more readily discriminated changes among speech sounds than among music sounds as indexed by the N2b response strength. Furthermore, during attentional listening, musicians displayed larger MMN and N2b than non-musicians for both music and speech sounds. Taken together, the data indicate that the discriminative abilities in human audition differ between music and speech sounds as a function of the sound-change context and the subjective familiarity of the sound parameters. These findings provide clear evidence for top-down modulatory effects in audition. In other words, the processing of sounds is realized by a dynamically adapting network considering type of sound, expertise and attentional demands, rather than by a strictly modularly organized stimulus-driven system.

45 CFR 1225.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 1605; National Origin Discrimination: 29 CFR part 1606; Age Discrimination: 45 CFR part 90; Handicap... DISCRIMINATION COMPLAINT PROCEDURE General Provisions § 1225.3 Definitions. Unless the context requires otherwise...) Illegal discrimination means discrimination on the basis of race, color, national origin, religion, age...

45 CFR 1225.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 1605; National Origin Discrimination: 29 CFR part 1606; Age Discrimination: 45 CFR part 90; Handicap... DISCRIMINATION COMPLAINT PROCEDURE General Provisions § 1225.3 Definitions. Unless the context requires otherwise...) Illegal discrimination means discrimination on the basis of race, color, national origin, religion, age...

45 CFR 1225.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 1605; National Origin Discrimination: 29 CFR part 1606; Age Discrimination: 45 CFR part 90; Handicap... DISCRIMINATION COMPLAINT PROCEDURE General Provisions § 1225.3 Definitions. Unless the context requires otherwise...) Illegal discrimination means discrimination on the basis of race, color, national origin, religion, age...

45 CFR 1225.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 1605; National Origin Discrimination: 29 CFR part 1606; Age Discrimination: 45 CFR part 90; Handicap... DISCRIMINATION COMPLAINT PROCEDURE General Provisions § 1225.3 Definitions. Unless the context requires otherwise...) Illegal discrimination means discrimination on the basis of race, color, national origin, religion, age...

45 CFR 1225.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 1605; National Origin Discrimination: 29 CFR part 1606; Age Discrimination: 45 CFR part 90; Handicap... DISCRIMINATION COMPLAINT PROCEDURE General Provisions § 1225.3 Definitions. Unless the context requires otherwise...) Illegal discrimination means discrimination on the basis of race, color, national origin, religion, age...

Discrimination and racial disparities in health: evidence and needed research

PubMed Central

Mohammed, Selina A.

2010-01-01

This paper provides a review and critique of empirical research on perceived discrimination and health. The patterns of racial disparities in health suggest that there are multiple ways by which racism can affect health. Perceived discrimination is one such pathway and the paper reviews the published research on discrimination and health that appeared in PubMed between 2005 and 2007. This recent research continues to document an inverse association between discrimination and health. This pattern is now evident in a wider range of contexts and for a broader array of outcomes. Advancing our understanding of the relationship between perceived discrimination and health will require more attention to situating discrimination within the context of other health-relevant aspects of racism, measuring it comprehensively and accurately, assessing its stressful dimensions, and identifying the mechanisms that link discrimination to health. PMID:19030981

Context-dependent similarity effects in letter recognition.

PubMed

Kinoshita, Sachiko; Robidoux, Serje; Guilbert, Daniel; Norris, Dennis

2015-10-01

In visual word recognition tasks, digit primes that are visually similar to letter string targets (e.g., 4/A, 8/B) are known to facilitate letter identification relative to visually dissimilar digits (e.g., 6/A, 7/B); in contrast, with letter primes, visual similarity effects have been elusive. In the present study we show that the visual similarity effect with letter primes can be made to come and go, depending on whether it is necessary to discriminate between visually similar letters. The results support a Bayesian view which regards letter recognition not as a passive activation process driven by the fixed stimulus properties, but as a dynamic evidence accumulation process for a decision that is guided by the task context.

Contextual Control of Discriminated Operant Behavior

PubMed Central

Bouton, Mark E.; Todd, Travis P.; León, Samuel P.

2014-01-01

Previous research suggests that changing the context after instrumental (operant) conditioning can weaken the strength of the operant response. That result contrasts with the results of studies of Pavlovian conditioning, where a context switch often does not affect the response elicited by a conditioned stimulus. To begin to make the methods more similar, Experiments 1–3 tested the effects of a context switch in rats on a discriminated operant response (R, lever pressing or chain pulling) that had been reinforced only in the presence of a 30-s discriminative stimulus (S, tone or light). As in Pavlovian conditioning, responses and reinforcers became confined to presentations of the S during training. However, in Experiment 1, after training in Context A, a switch to Context B caused a decrement in responding during S. In Experiment 2, a switch to Context B likewise decreased responding in S when Context B was equally familiar, equally associated with reinforcement, or equally associated with the training of a discriminated operant (a different R reinforced in a different S). However, there was no decrement if Context B had been associated with the same response that was trained in Context A (Experiments 2 and 3). The effectiveness of S transferred across contexts, whereas the strength of the response did not. Experiment 4 found that a continuously reinforced response was also disrupted by context change when the same response manipulandum was used in both training and testing. Overall, the results suggest that the context can have a robust general role in the control of operant behavior. Mechanisms of contextual control are discussed. PMID:24000907

Contextual control of discriminated operant behavior.

PubMed

Bouton, Mark E; Todd, Travis P; León, Samuel P

2014-01-01

Previous research has suggested that changing the context after instrumental (operant) conditioning can weaken the strength of the operant response. That result contrasts with the results of studies of Pavlovian conditioning, in which a context switch often does not affect the response elicited by a conditioned stimulus. To begin to make the methods more similar, Experiments 1-3 tested the effects of a context switch in rats on a discriminated operant response (R; lever pressing or chain pulling) that had been reinforced only in the presence of a 30-s discriminative stimulus (S; tone or light). As in Pavlovian conditioning, responses and reinforcers became confined to presentations of the S during training. However, in Experiment 1, after training in Context A, a switch to Context B caused a decrement in responding during S. In Experiment 2, a switch to Context B likewise decreased responding in S when Context B was equally familiar, equally associated with reinforcement, or equally associated with the training of a discriminated operant (a different R reinforced in a different S). However, there was no decrement if Context B had been associated with the same response that was trained in Context A (Experiments 2 and 3). The effectiveness of S transferred across contexts, whereas the strength of the response did not. Experiment 4 found that a continuously reinforced response was also disrupted by context change when the same response manipulandum was used in both training and testing. Overall, the results suggest that the context can have a robust general role in the control of operant behavior. Mechanisms of contextual control are discussed.

Discrimination of phoneme length differences in word and sentence contexts

NASA Astrophysics Data System (ADS)

Kawai, Norimune; Carrell, Thomas

2005-09-01

The ability of listeners to discriminate phoneme duration differences within word and sentence contexts was measured. This investigation was part of a series of studies examining the audibility and perceptual importance of speech modifications produced by stuttering intervention techniques. Just noticeable differences (jnd's) of phoneme lengths were measured via the parameter estimation by sequential testing (PEST) task, an adaptive tracking procedure. The target phonemes were digitally manipulated to vary from normal (130 m) to prolonged (210 m) duration in 2-m increments. In the first condition the phonemes were embedded in words. In the second condition the phonemes were embedded within words, which were further embedded in sentences. A four-interval forced-choice (4IAX) task was employed on each trial, and the PEST procedure determined the duration at which each listener correctly detected a difference between the normal duration and the test duration 71% of the time. The results revealed that listeners were able to reliably discriminate approximately 15-m differences in word context and 10-m differences in sentence context. An independent t-test showed a difference in discriminability between word and sentence contexts to be significant. These results indicate that duration differences were better perceived within a sentence context.

A historical analysis of public health, the law, and stigmatized social groups: the need for both obesity and weight bias legislation.

PubMed

Pomeranz, Jennifer L

2008-11-01

History teaches that discrimination against socially undesirable groups leads to societal and governmental neglect of the stigmatized group's health problem. By placing weight discrimination in a historical context, this article demonstrates that legislation specifically aimed at rectifying obesity is less likely while weight bias is socially acceptable. Beyond obesity legislation, public health professionals may consider advocating for legislation directly targeting discrimination based on weight. This article reviews the history of discrimination against distinct groups and provides statutory solutions for discrimination based on weight. In addition to revising current statutes and regulatory rules, a unique statute targeting weight bias in the employment context is considered.

Roles of context in acquisition of human instrumental learning: Implications for the understanding of the mechanisms underlying context-switch effects.

PubMed

Gámez, A Matías; León, Samuel P; Rosas, Juan M

2017-09-01

Four experiments in human instrumental learning explored the associations involving the context that develop after three trials of training on simple discriminations. Experiments 1 and 4 found a deleterious effect of switching the learning context that cannot be explained by the context-outcome binary associations commonly used to explain context-switch effects after short training in human predictive learning and in animal Pavlovian conditioning. Evidence for context-outcome (Experiment 2), context-discriminative stimulus (Experiment 3), and context-instrumental response (Experiment 4) binary associations was found within the same training paradigm, suggesting that contexts became associated with all the elements of the situation, regardless of whether those associations played a role in a specific context-switch effect detected on performance.

The Discriminant Value of Phase-Dependent Local Dynamic Stability of Daily Life Walking in Older Adult Community-Dwelling Fallers and Nonfallers

PubMed Central

Ihlen, Espen A. F.; Weiss, Aner; Helbostad, Jorunn L.; Hausdorff, Jeffrey M.

2015-01-01

The present study compares phase-dependent measures of local dynamic stability of daily life walking with 35 conventional gait features in their ability to discriminate between community-dwelling older fallers and nonfallers. The study reanalyzes 3D-acceleration data of 3-day daily life activity from 39 older people who reported less than 2 falls during one year and 31 who reported two or more falls. Phase-dependent local dynamic stability was defined for initial perturbation at 0%, 20%, 40%, 60%, and 80% of the step cycle. A partial least square discriminant analysis (PLS-DA) was used to compare the discriminant abilities of phase-dependent local dynamic stability with the discriminant abilities of 35 conventional gait features. The phase-dependent local dynamic stability λ at 0% and 60% of the step cycle discriminated well between fallers and nonfallers (AUC = 0.83) and was significantly larger (p < 0.01) for the nonfallers. Furthermore, phase-dependent λ discriminated as well between fallers and nonfallers as all other gait features combined. The present result suggests that phase-dependent measures of local dynamic stability of daily life walking might be of importance for further development in early fall risk screening tools. PMID:26491669

Behavioral Momentum Theory: Equations and Applications

ERIC Educational Resources Information Center

Nevin, John A.; Shahan, Timothy A.

2011-01-01

Behavioral momentum theory provides a quantitative account of how reinforcers experienced within a discriminative stimulus context govern the persistence of behavior that occurs in that context. The theory suggests that all reinforcers obtained in the presence of a discriminative stimulus increase resistance to change, regardless of whether those…

A novel form of perceptual attunement: Context-dependent perception of a native contrast in 14-month-old infants.

PubMed

Fort, Mathilde; Brusini, Perrine; Carbajal, M Julia; Sun, Yue; Peperkamp, Sharon

2017-08-01

By the end of their first year of life, infants have become experts in discriminating the sounds of their native language, while they have lost the ability to discriminate non-native contrasts. This type of phonetic learning is referred to as perceptual attunement. In the present study, we investigated the emergence of a context-dependent form of perceptual attunement in infancy. Indeed, some native contrasts are not discriminated in certain phonological contexts by adults, due to the presence of a language-specific process that neutralizes the contrasts in those contexts. We used a mismatch design and recorded high-density Electroencephalography (EEG) in French-learning 14-month-olds. Our results show that similarly to French adults, infants fail to discriminate a native voicing contrast (e.g., [f] vs. [v]) when it occurs in a specific phonological context (e.g. [ofbe] vs. [ovbe], no mismatch response), while they successfully detected it in other phonological contexts (e.g., [ofne] vs. [ovne], mismatch response). The present results demonstrate for the first time that by the age of 14 months, infants' phonetic learning does not only rely on the processing of individual sounds, but also takes into account in a language-specific manner the phonological contexts in which these sounds occur. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

A multidisciplinary selection model for youth soccer: the Ghent Youth Soccer Project

PubMed Central

Vaeyens, R; Malina, R M; Janssens, M; Van Renterghem, B; Bourgois, J; Vrijens, J; Philippaerts, R M

2006-01-01

Objectives To determine the relationships between physical and performance characteristics and level of skill in youth soccer players aged 12–16 years. Methods Anthropometry, maturity status, functional and sport‐specific parameters were assessed in elite, sub‐elite, and non‐elite youth players in four age groups: U13 (n = 117), U14 (n = 136), U15 (n = 138) and U16 (n = 99). Results Multivariate analyses of covariance by age group with maturity status as the covariate showed that elite players scored better than the non‐elite players on strength, flexibility, speed, aerobic endurance, anaerobic capacity and several technical skills (p<0.05). Stepwise discriminant analyses showed that running speed and technical skills were the most important characteristics in U13 and U14 players, while cardiorespiratory endurance was more important in U15 and U16 players. The results suggest that discriminating characteristics change with competitive age levels. Conclusions Characteristics that discriminate youth soccer players vary by age group. Talent identification models should thus be dynamic and provide opportunities for changing parameters in a long‐term developmental context. PMID:16980535

Contributions of acculturation, enculturation, discrimination, and personality traits to social anxiety among Chinese immigrants: A context-specific assessment.

PubMed

Fang, Ke; Friedlander, Myrna; Pieterse, Alex L

2016-01-01

Based on the diathesis-stress model of anxiety, this study examined the contributions of cultural processes, perceived racial discrimination, and personality traits to social anxiety among Chinese immigrants. Further guided by the theory of intergroup anxiety, this study also adopted a context-specific approach to distinguish between participants' experience of social anxiety when interacting with European Americans versus with other Chinese in the United States. This quantitative and ex post facto study used a convenience sample of 140 first-generation Chinese immigrants. Participants were recruited through e-mails from different university and community groups across the United States. The sample includes 55 men and 82 women (3 did not specify) with an average age of 36 years old. Results showed that more social anxiety was reported in the European American context than in the Chinese ethnic context. The full models accounted for almost half the variance in anxiety in each context. Although personality accounted for the most variance, the cultural variables and discrimination contributed 14% of the unique variance in the European American context. Notably, low acculturation, high neuroticism, and low extraversion were unique contributors to social anxiety with European Americans, whereas in the Chinese ethnic context only low extraversion was a unique contributor; more discrimination was uniquely significant in both contexts. The findings suggest a need to contextualize the research and clinical assessment of social anxiety, and have implications for culturally sensitive counseling with immigrants. (c) 2016 APA, all rights reserved).

Stress within a Bicultural Context for Adolescents of Mexican Descent.

ERIC Educational Resources Information Center

Romero, Andrea J.; Roberts, Robert E.

2003-01-01

Folkman and Lazarus's theory of stress and coping was used to develop a measure assessing the perceived stress within a bicultural context. Middle school students of Mexican descent (N=881) reported their perceived stress from intergenerational acculturation gaps, within-group discrimination, out-group discrimination, and monolingual stress.…

Rats with ventral hippocampal damage are impaired at various forms of learning including conditioned inhibition, spatial navigation, and discriminative fear conditioning to similar contexts.

PubMed

McDonald, Robert J; Balog, R J; Lee, Justin Q; Stuart, Emily E; Carrels, Brianna B; Hong, Nancy S

2018-10-01

The ventral hippocampus (vHPC) has been implicated in learning and memory functions that seem to differ from its dorsal counterpart. The goal of this series of experiments was to provide further insight into the functional contributions of the vHPC. Our previous work implicated the vHPC in spatial learning, inhibitory learning, and fear conditioning to context. However, the specific role of vHPC on these different forms of learning are not clear. Accordingly, we assessed the effects of neurotoxic lesions of the ventral hippocampus on retention of a conditioned inhibitory association, early versus late spatial navigation in the water task, and discriminative fear conditioning to context under high ambiguity conditions. The results showed that the vHPC was necessary for the expression of conditioned inhibition, early spatial learning, and discriminative fear conditioning to context when the paired and unpaired contexts have high cue overlap. We argue that this pattern of effects, combined with previous work, suggests a key role for vHPC in the utilization of broad contextual representations for inhibition and discriminative memory in high ambiguity conditions. Copyright © 2018 Elsevier B.V. All rights reserved.

Modeling phoneme perception. II: A model of stop consonant discrimination.

PubMed

van Hessen, A J; Schouten, M E

1992-10-01

Combining elements from two existing theories of speech sound discrimination, dual process theory (DPT) and trace context theory (TCT), a new theory, called phoneme perception theory, is proposed, consisting of a long-term phoneme memory, a context-coding memory, and a trace memory, each with its own time constants. This theory is tested by means of stop-consonant discrimination data in which interstimulus interval (ISI; values of 100, 300, and 2000 ms) is an important variable. It is shown that discrimination in which labeling plays an important part (2IFC and AX between category) benefits from increased ISI, whereas discrimination in which only sensory traces are compared (AX within category), decreases with increasing ISI. The theory is also tested on speech discrimination data from the literature in which ISI is a variable [Pisoni, J. Acoust. Soc. Am. 36, 277-282 (1964); Cowan and Morse, J. Acoust. Soc. Am. 79, 500-507 (1986)]. It is concluded that the number of parameters in trace context theory is not sufficient to account for most speech-sound discrimination data and that a few additional assumptions are needed, such as a form of sublabeling, in which subjects encode the quality of a stimulus as a member of a category, and which requires processing time.

Aging and curvature discrimination from static and dynamic touch.

PubMed

Norman, J Farley; Kappers, Astrid M L; Cheeseman, Jacob R; Ronning, Cecilia; Thomason, Kelsey E; Baxter, Michael W; Calloway, Autum B; Lamirande, Davora N

2013-01-01

Two experiments evaluated the ability of 30 older and younger adults to discriminate the curvature of simple object surfaces from static and dynamic touch. The ages of the older adults ranged from 66 to 85 years, while those of the younger adults ranged from 20 to 29 years. For each participant in both experiments, the minimum curvature magnitude needed to reliably discriminate between convex and concave surfaces was determined. In Experiment 1, participants used static touch to make their judgments of curvature, while dynamic touch was used in Experiment 2. When static touch was used to discriminate curvature, a large effect of age occurred (the thresholds were 0.67 & 1.11/m for the younger and older participants, respectively). However, when participants used dynamic touch, there was no significant difference between the ability of younger and older participants to discriminate curvature (the thresholds were 0.58 & 0.59/m for the younger and older participants, respectively). The results of the current study demonstrate that while older adults can accurately discriminate surface curvature from dynamic touch, they possess significant impairments for static touch.

Aging and Curvature Discrimination from Static and Dynamic Touch

PubMed Central

Norman, J. Farley; Kappers, Astrid M. L.; Cheeseman, Jacob R.; Ronning, Cecilia; Thomason, Kelsey E.; Baxter, Michael W.; Calloway, Autum B.; Lamirande, Davora N.

2013-01-01

Two experiments evaluated the ability of 30 older and younger adults to discriminate the curvature of simple object surfaces from static and dynamic touch. The ages of the older adults ranged from 66 to 85 years, while those of the younger adults ranged from 20 to 29 years. For each participant in both experiments, the minimum curvature magnitude needed to reliably discriminate between convex and concave surfaces was determined. In Experiment 1, participants used static touch to make their judgments of curvature, while dynamic touch was used in Experiment 2. When static touch was used to discriminate curvature, a large effect of age occurred (the thresholds were 0.67 & 1.11/m for the younger and older participants, respectively). However, when participants used dynamic touch, there was no significant difference between the ability of younger and older participants to discriminate curvature (the thresholds were 0.58 & 0.59/m for the younger and older participants, respectively). The results of the current study demonstrate that while older adults can accurately discriminate surface curvature from dynamic touch, they possess significant impairments for static touch. PMID:23844224

Motifs, modules and games in bacteria.

PubMed

Wolf, Denise M; Arkin, Adam P

2003-04-01

Global explorations of regulatory network dynamics, organization and evolution have become tractable thanks to high-throughput sequencing and molecular measurement of bacterial physiology. From these, a nascent conceptual framework is developing, that views the principles of regulation in term of motifs, modules and games. Motifs are small, repeated, and conserved biological units ranging from molecular domains to small reaction networks. They are arranged into functional modules, genetically dissectible cellular functions such as the cell cycle, or different stress responses. The dynamical functioning of modules defines the organism's strategy to survive in a game, pitting cell against cell, and cell against environment. Placing pathway structure and dynamics into an evolutionary context begins to allow discrimination between those physical and molecular features that particularize a species to its surroundings, and those that provide core physiological function. This approach promises to generate a higher level understanding of cellular design, pathway evolution and cellular bioengineering.

Motifs, modules and games in bacteria

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

Wolf, Denise M.; Arkin, Adam P.

2003-04-01

Global explorations of regulatory network dynamics, organization and evolution have become tractable thanks to high-throughput sequencing and molecular measurement of bacterial physiology. From these, a nascent conceptual framework is developing, that views the principles of regulation in term of motifs, modules and games. Motifs are small, repeated, and conserved biological units ranging from molecular domains to small reaction networks. They are arranged into functional modules, genetically dissectible cellular functions such as the cell cycle, or different stress responses. The dynamical functioning of modules defines the organism's strategy to survive in a game, pitting cell against cell, and cell against environment.more » Placing pathway structure and dynamics into an evolutionary context begins to allow discrimination between those physical and molecular features that particularize a species to its surroundings, and those that provide core physiological function. This approach promises to generate a higher level understanding of cellular design, pathway evolution and cellular bioengineering.« less

Racial Attitudes, Physician-Patient Talk Time Ratio, and Adherence in Racially Discordant Medical Interactions

PubMed Central

Hagiwara, Nao; Penner, Louis A.; Gonzalez, Richard; Eggly, Susan; Dovidio, John F.; Gaertner, Samuel L.; West, Tessa; Albrecht, Terrance L.

2013-01-01

Physician racial bias and patient perceived discrimination have each been found to influence perceptions of and feelings about racially discordant medical interactions. However, to our knowledge, no studies have examined how they may simultaneously influence the dynamics of these interactions. This study examined how (a) non-Black primary care physicians’ explicit and implicit racial bias and (b) Black patients’ perceived past discrimination affected physician-patient talk time ratio (i.e., the ratio of physician to patient talk time) during medical interactions and the relationship between this ratio and patients’ subsequent adherence. We conducted a secondary analysis of self-report and video-recorded data from a prior study of clinical interactions between 112 low-income, Black patients and their 14 non-Black physicians at a primary care clinic in the Midwestern United States between June, 2006 and February, 2008. Overall, physicians talked more than patients; however, both physician bias and patient perceived past discrimination affected physician-patient talk time ratio. Non-Black physicians with higher levels of implicit, but not explicit, racial bias had larger physician-patient talk time ratios than did physicians with lower levels of implicit bias, indicating that physicians with more negative implicit racial attitudes talked more than physicians with less negative racial attitudes. Additionally, Black patients with higher levels of perceived discrimination had smaller physician-patient talk time ratios, indicating that patients with more negative racial attitudes talked more than patients with less negative racial attitudes. Finally, smaller physician-patient talk time ratios were associated with less patient subsequent adherence, indicating that patients who talked more during the racially discordant medical interactions were less likely to adhere subsequently. Theoretical and practical implications of these findings are discussed in the context of factors that affect the dynamics of racially discordant medical interactions. PMID:23631787

NR2B-dependent plasticity of adult-born granule cells is necessary for context discrimination.

PubMed

Kheirbek, Mazen A; Tannenholz, Lindsay; Hen, René

2012-06-20

Adult-generated granule cells (GCs) in the dentate gyrus (DG) exhibit a period of heightened plasticity 4-6 weeks postmitosis. However, the functional contribution of this critical window of plasticity to hippocampal neurogenesis and behavior remains unknown. Here, we show that deletion of NR2B-containing NMDA receptors from adult-born GCs impairs a neurogenesis-dependent form of LTP in the DG and reduces dendritic complexity of adult-born GCs, but does not impact their survival. Mice in which the NR2B-containing NMDA receptor was deleted from adult-born GCs did not differ from controls in baseline anxiety-like behavior or discrimination of very different contexts, but were impaired in discrimination of highly similar contexts. These results indicate that NR2B-dependent plasticity of adult-born GCs is necessary for fine contextual discrimination and is consistent with their proposed role in pattern separation.

The Context of Workplace Sex Discrimination: Sex Composition, Workplace Culture and Relative Power

ERIC Educational Resources Information Center

Stainback, Kevin; Ratliff, Thomas N.; Roscigno, Vincent J.

2011-01-01

Building on prior work surrounding negative work-related experiences, such as workplace bullying and sexual harassment, we examine the extent to which organizational context is meaningful for the subjective experience of sex discrimination. Data draw on the 2002 National Study of the Changing Workforce, which provides a key indicator of…

Conservation laws and stress-energy-momentum tensors for systems with background fields

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

Gratus, Jonathan, E-mail: j.gratus@lancaster.ac.uk; The Cockcroft Institute, Daresbury Laboratory, Warrington WA4 4AD; Obukhov, Yuri N., E-mail: yo@thp.uni-koeln.de

2012-10-15

This article attempts to delineate the roles played by non-dynamical background structures and Killing symmetries in the construction of stress-energy-momentum tensors generated from a diffeomorphism invariant action density. An intrinsic coordinate independent approach puts into perspective a number of spurious arguments that have historically lead to the main contenders, viz the Belinfante-Rosenfeld stress-energy-momentum tensor derived from a Noether current and the Einstein-Hilbert stress-energy-momentum tensor derived in the context of Einstein's theory of general relativity. Emphasis is placed on the role played by non-dynamical background (phenomenological) structures that discriminate between properties of these tensors particularly in the context of electrodynamics inmore » media. These tensors are used to construct conservation laws in the presence of Killing Lie-symmetric background fields. - Highlights: Black-Right-Pointing-Pointer The role of background fields in diffeomorphism invariant actions is demonstrated. Black-Right-Pointing-Pointer Interrelations between different stress-energy-momentum tensors are emphasised. Black-Right-Pointing-Pointer The Abraham and Minkowski electromagnetic tensors are discussed in this context. Black-Right-Pointing-Pointer Conservation laws in the presence of nondynamic background fields are formulated. Black-Right-Pointing-Pointer The discussion is facilitated by the development of a new variational calculus.« less

Compensatory strategies for reducing interpersonal discrimination: the effectiveness of acknowledgments, increased positivity, and individuating information.

PubMed

Singletary, Sarah L; Hebl, Michelle R

2009-05-01

Previous research has revealed, across a number of contexts, that stigmatized individuals are the recipients of interpersonal discrimination (e.g., M. R. Hebl, J. B. Foster, L. M. Mannix, & J. F. Dovidio, 2002). Such discrimination has been linked to a number of negative outcomes in the workplace, both for stigmatized individuals and for organizations as a whole (see, e.g., E. B. King, J. L. Shapiro, M. R. Hebl, S. L. Singletary, & S. Turner, 2006; C. O. Word, M. P. Zanna, & J. Cooper, 1974). The current research examines 3 individual-level compensatory strategies aimed at reducing interpersonal discrimination. Results reveal that compensatory strategies are successful in reducing interpersonal discrimination in job application contexts and that such strategies uniquely benefit stigmatized individuals. (c) 2009 APA, all rights reserved.

Gender Discrimination and Sexual Harassment in Medical Education: Perspectives Gained by a 14-School Study.

ERIC Educational Resources Information Center

Nora, Lois Margaret; McLaughlin, Margaret A.; Fosson, Sue E.; Stratton, Terry D.; Murphy-Spencer, Amy; Fincher, Ruth-Marie E.; German, Deborah C.; Seiden, David; Witzke, Donald B.

2002-01-01

Surveyed medical students about their exposures to and perceptions of gender discrimination and sexual harassment (GD/SH) in selected academic and nonacademic contexts. Findings included that more women than men reported all types of GD/SH across all contexts, and that GD/SH is prevalent in undergraduate medical education, particularly within core…

Contextual and Serial Discriminations: A New Learning Paradigm to Assess Simultaneously the Effects of Acute Stress on Retrieval of Flexible or Stable Information in Mice

PubMed Central

Célérier, Aurélie; Piérard, Christophe; Rachbauer, Dagmar; Sarrieau, Alain; Béracochéa, Daniel

2004-01-01

The present study was aimed at simultaneously determining on the same subject, the effects of stress on retrieval of flexible (contextual or temporal) or stable (spatial) information. Three behavioral paradigms carried out in a four-hole board were designed as follows: (1) Simple Discrimination (SD), in which mice learned a single discrimination; (2) Contextual and Serial Discriminations (CSD), in which mice learned two successive discriminations on two different internal contexts; (3) Spatial Serial Discriminations (SSD), in which mice learned two successive discriminations on an identical internal context. The stressor (three inescapable electric footshocks) was delivered 5 min before retention, occurring 5 min or 24 h after acquisition. Results showed that this stressor increased plasmatic corticosterone levels and fear reactivity in an elevated-plus-maze, as compared with nonstressed mice. The stressor reversed the normal pattern of retrieval observed in nonstressed controls in the CSD task, this effect being context dependent, as it was not observed in the SSD task. Overall, our study shows that stress affected the retrieval of flexible and old information, but spared the retrieval of stable or recent ones. Therefore, these behavioral paradigms allow us to study simultaneously, on the same animal, the effects of stress on distinct forms of memory retrieval. PMID:15054135

Measuring the effect of ethnic and non-ethnic discrimination on Europeans' self-rated health.

PubMed

Alvarez-Galvez, Javier

2016-04-01

The study of perceived discrimination based on race and ethnic traits belongs to a long-held tradition in this field, but recent studies have found that non-ethnic discrimination based on factors such as gender, disability or age is also a crucial predictor of health outcomes. Using data from the European Social Survey (2010), and applying Boolean Factor Analysis and Ordered Logistic Regression models, this study is aimed to compare how ethnic and non-ethnic types of discrimination might affect self-rated health in the European context. We found that non-ethnic types of discrimination produce stronger differences on health outcomes. This result indicates that the probabilities of presenting a poor state of health are significantly higher when individuals feel they are being discriminated against for social or demographic conditions (gender, age, sexuality or disability) rather than for ethnic reasons (nationality, race, ethnicity, language or religiosity). This study offers a clear comparison of health inequalities based on ethnic and non-ethnic types of discrimination in the European context, overcoming analytical based on binary indicators and simple measures of discrimination.

Kin discrimination within honey bee (Apis mellifera) colonies: An analysis of the evidence.

PubMed

Breed, M D; Welch, C K; Cruz, R

1994-12-01

Compelling evolutionary arguments lead to the prediction that honey bee workers should discriminate between supersisters and half-sisters within colonies. We review the theoretical support for discrimination during swarming, queen rearing, feeding, and grooming. A survey of the data that tests whether such discrimination takes place shows that, despite substantial effort in a number of laboratories, there is no conclusive evidence for intracolony discrimination in any of the postulated contexts. The strongest suggestive data is in the critical context of queen rearing, but flaws in experimental design or analysis make the best available tests inconclusive. We present new data that shows that cues exist on which discriminations can be made among adult workers in nestmate recognition interactions and in feeding interactions, but our data does not differentiate between subfamily recognition and recognition associated with color phenotypes. We conclude that while selection may favor discrimination between supersisters and half-sisters, as a practical matter such discriminations play no role, or only a minor role, in the biology of the honey bee. Copyright © 1994. Published by Elsevier B.V.

Discrimination of static and dynamic spectral patterns by children and young adults in relationship to speech perception in noise.

PubMed

Rayes, Hanin; Sheft, Stanley; Shafiro, Valeriy

2014-01-01

Past work has shown relationship between the ability to discriminate spectral patterns and measures of speech intelligibility. The purpose of this study was to investigate the ability of both children and young adults to discriminate static and dynamic spectral patterns, comparing performance between the two groups and evaluating within-group results in terms of relationship to speech-in-noise perception. Data were collected from normal-hearing children (age range: 5.4 - 12.8 yrs) and young adults (mean age: 22.8 yrs) on two spectral discrimination tasks and speech-in-noise perception. The first discrimination task, involving static spectral profiles, measured the ability to detect a change in the phase of a low-density sinusoidal spectral ripple of wideband noise. Using dynamic spectral patterns, the second task determined the signal-to-noise ratio needed to discriminate the temporal pattern of frequency fluctuation imposed by stochastic low-rate frequency modulation (FM). Children performed significantly poorer than young adults on both discrimination tasks. For children, a significant correlation between speech-in-noise perception and spectral-pattern discrimination was obtained only with the dynamic patterns of the FM condition, with partial correlation suggesting that factors related to the children's age mediated the relationship.

Multiple discriminations experienced by people living with HIV in France: results from the ANRS-Vespa2 study.

PubMed

Marsicano, Elise; Dray-Spira, Rosemary; Lert, France; Aubrière, Cindy; Spire, Bruno; Hamelin, Christine

2014-01-01

Since the advent of AIDS, discrimination has remained at the core of the experience of people living with HIV (PLHIV). PLHIV who belong to minority groups are exposed to discrimination not only on the grounds of their HIV infection but also because of rejecting attitudes towards drug users, homosexuals and black people. This article aimed to measure the frequency of discrimination and assess its correlates among PLHIV in France. We used data from a national representative survey, the ANRS-Vespa2 study, conducted in France in 2011 among 3022 male and female HIV-positive patients followed at hospitals. Respondents answered a face-to-face questionnaire documenting their health status and living conditions. Discrimination was documented during the previous two years on the grounds of HIV infection, gender, country of birth, skin colour, sexual orientation, place of residence, and substance abuse in a variety of contexts. For each context, we performed logistic regressions on discrimination, controlling for socio-epidemiological group, age, education level and employment status. Discrimination is frequently experienced by PLHIV in France (26%), particularly when applying for a job (24%), interacting with family (11%) or seeking health services (8%). Women from sub-Saharan Africa reported the highest levels of discrimination, whereas heterosexual non-African men reported the lowest. Men who have sex with men experienced levels of discrimination that fell between those of these two groups. The major perceived reason for discrimination was HIV status (13%). Nationality, skin colour and sexual orientation were cited by 5% each, whereas gender was cited by 1% of respondents. Our analyses show that discrimination is a frequent and cross-cutting experience with differences across the various contexts and among the diverse subpopulations. The intertwining of HIV-related stigma with sexism, racism and homophobia needs to be addressed to understand why discrimination against PLHIV persists when the disease itself has greatly evolved.

Revising two-point discrimination assessment in normal aging and in patients with polyneuropathies.

PubMed

van Nes, S I; Faber, C G; Hamers, R M T P; Harschnitz, O; Bakkers, M; Hermans, M C E; Meijer, R J; van Doorn, P A; Merkies, I S J

2008-07-01

To revise the static and dynamic normative values for the two-point discrimination test and to examine its applicability and validity in patients with a polyneuropathy. Two-point discrimination threshold values were assessed in 427 healthy controls and 99 patients mildly affected by a polyneuropathy. The controls were divided into seven age groups ranging from 20-29, 30-39,..., up to 80 years and older; each group consisted of at least 30 men and 30 women. Two-point discrimination examination took place under standardised conditions on the index finger. Correlation studies were performed between the scores obtained and the values derived from the Weinstein Enhanced Sensory Test (WEST) and the arm grade of the Overall Disability SumScore (ODSS) in the patients' group (validity studies). Finally, the sensitivity to detect patients mildly affected by a polyneuropathy was evaluated for static and dynamic assessments. There was a significant age-dependent increase in the two-point discrimination values. No significant gender difference was found. The dynamic threshold values were lower than the static scores. The two-point discrimination values obtained correlated significantly with the arm grade of the ODSS (static values: r = 0.33, p = 0.04; dynamic values: r = 0.37, p = 0.02) and the scores of the WEST in patients (static values: r = 0.58, p = 0.0001; dynamic values: r = 0.55, p = 0.0002). The sensitivity for the static and dynamic threshold values was 28% and 33%, respectively. This study provides age-related normative two-point discrimination threshold values using a two-point discriminator (an aesthesiometer). This easily applicable instrument could be used as part of a more extensive neurological sensory evaluation.

Cumulative trauma, gender discrimination and mental health in women: mediating role of self-esteem.

PubMed

Kucharska, Justyna

2017-12-20

Evidence suggests that women show symptoms of trauma-related symptoms more often than men. Gender discrimination is also associated with the severity of symptoms in women. This study explored the relations among cumulative trauma, gender discrimination and mental health in women with a mediating role of self-esteem and emotion regulation. Two types of gender discrimination were taken into account: discrimination by parents and in the social context. Cumulative trauma over the lifetime was assessed, as well as three types of symptoms: internalising, externalising, psychoticism. A total of 277 females from Poland participated in the study. It was hypothesised that gender discrimination and cumulative trauma would be positively related to symptoms and that lowered self-esteem mediates these relations. Hypotheses received partial confirmation, as both gender discrimination and cumulative trauma have been shown to be related to three types of symptoms. Self-esteem was a partial mediator between gender discrimination in the social context and symptoms. It was also demonstrated that emotion suppression is a partial mediator between cumulative trauma and symptoms. It has been demonstrated that socio-cultural factors, such as gender discrimination, play an important role in psychiatric symptoms development.

Deficits of congenital amusia beyond pitch: Evidence from impaired categorical perception of vowels in Cantonese-speaking congenital amusics

PubMed Central

Shao, Jing; Huang, Xunan

2017-01-01

Congenital amusia is a lifelong disorder of fine-grained pitch processing in music and speech. However, it remains unclear whether amusia is a pitch-specific deficit, or whether it affects frequency/spectral processing more broadly, such as the perception of formant frequency in vowels, apart from pitch. In this study, in order to illuminate the scope of the deficits, we compared the performance of 15 Cantonese-speaking amusics and 15 matched controls on the categorical perception of sound continua in four stimulus contexts: lexical tone, pure tone, vowel, and voice onset time (VOT). Whereas lexical tone, pure tone and vowel continua rely on frequency/spectral processing, the VOT continuum depends on duration/temporal processing. We found that the amusic participants performed similarly to controls in all stimulus contexts in the identification, in terms of the across-category boundary location and boundary width. However, the amusic participants performed systematically worse than controls in discriminating stimuli in those three contexts that depended on frequency/spectral processing (lexical tone, pure tone and vowel), whereas they performed normally when discriminating duration differences (VOT). These findings suggest that the deficit of amusia is probably not pitch specific, but affects frequency/spectral processing more broadly. Furthermore, there appeared to be differences in the impairment of frequency/spectral discrimination in speech and nonspeech contexts. The amusic participants exhibited less benefit in between-category discriminations than controls in speech contexts (lexical tone and vowel), suggesting reduced categorical perception; on the other hand, they performed inferiorly compared to controls across the board regardless of between- and within-category discriminations in nonspeech contexts (pure tone), suggesting impaired general auditory processing. These differences imply that the frequency/spectral-processing deficit might be manifested differentially in speech and nonspeech contexts in amusics—it is manifested as a deficit of higher-level phonological processing in speech sounds, and as a deficit of lower-level auditory processing in nonspeech sounds. PMID:28829808

Context-Dependent Duration Signals in the Primate Prefrontal Cortex

PubMed Central

Genovesio, Aldo; Seitz, Lucia K.; Tsujimoto, Satoshi; Wise, Steven P.

2016-01-01

The activity of some prefrontal (PF) cortex neurons distinguishes short from long time intervals. Here, we examined whether this property reflected a general timing mechanism or one dependent on behavioral context. In one task, monkeys discriminated the relative duration of 2 stimuli; in the other, they discriminated the relative distance of 2 stimuli from a fixed reference point. Both tasks had a pre-cue period (interval 1) and a delay period (interval 2) with no discriminant stimulus. Interval 1 elapsed before the presentation of the first discriminant stimulus, and interval 2 began after that stimulus. Both intervals had durations of either 400 or 800 ms. Most PF neurons distinguished short from long durations in one task or interval, but not in the others. When neurons did signal something about duration for both intervals, they did so in an uncorrelated or weakly correlated manner. These results demonstrate a high degree of context dependency in PF time processing. The PF, therefore, does not appear to signal durations abstractedly, as would be expected of a general temporal encoder, but instead does so in a highly context-dependent manner, both within and between tasks. PMID:26209845

Discriminatory power of water polo game-related statistics at the 2008 Olympic Games.

PubMed

Escalante, Yolanda; Saavedra, Jose M; Mansilla, Mirella; Tella, Victor

2011-02-01

The aims of this study were (1) to compare water polo game-related statistics by context (winning and losing teams) and sex (men and women), and (2) to identify characteristics discriminating the performances for each sex. The game-related statistics of the 64 matches (44 men's and 20 women's) played in the final phase of the Olympic Games held in Beijing in 2008 were analysed. Unpaired t-tests compared winners and losers and men and women, and confidence intervals and effect sizes of the differences were calculated. The results were subjected to a discriminant analysis to identify the differentiating game-related statistics of the winning and losing teams. The results showed the differences between winning and losing men's teams to be in both defence and offence, whereas in women's teams they were only in offence. In men's games, passing (assists), aggressive play (exclusions), centre position effectiveness (centre shots), and goalkeeper defence (goalkeeper-blocked 5-m shots) predominated, whereas in women's games the play was more dynamic (possessions). The variable that most discriminated performance in men was goalkeeper-blocked shots, and in women shooting effectiveness (shots). These results should help coaches when planning training and competition.

Gender-related biases in evaluations of sex discrimination allegations: is perceived threat the key?

PubMed

Elkins, Teri J; Phillips, James S; Konopaske, Robert

2002-04-01

Hypotheses derived from defensive attribution theory and social identity theory were tested in 3 laboratory experiments examining the effects of plaintiff and observer gender on perceived threat, plaintiff identification, and sex discrimination. In Study 1, women differentiated plaintiffs on the basis of gender, whereas men did not. Study 2 showed that this bias occurred because employment discrimination was personally threatening to women but not to men. In Study 3, the bias was reversed in a child custody context. As predicted, men found this context to be significantly more threatening than did women and subsequently exhibited a similarity bias. Mediation analyses suggested that responsibility attributions explained most of the variance in discrimination judgments associated with the plaintiff gender by observer gender interactions.

Context-dependent discrimination and the evolution of mimicry.

PubMed

Holen, Øistein Haugsten; Johnstone, Rufus A

2006-03-01

Many mimetic organisms have evolved a close resemblance to their models, making it difficult to discriminate between them on the basis of appearance alone. However, if mimics and models differ slightly in their activity patterns, behavior, or use of microhabitats, the exact circumstances under which a signaler is encountered may provide additional clues to its identity. We employ an optimality model of mimetic discrimination in which signal receivers obtain information about the relative risk of encountering mimics and models by observing an external background cue and flexibly adjust their response thresholds. Although such flexibility on the part of signal receivers has been predicted by theory and is supported by empirical evidence in a range of biological settings, little is known about the effects it has on signalers. We show that the presence of external cues that partly reveal signaler identity may benefit models and harm mimics, harm both, or even benefit both, depending on ecological circumstances. Moreover, if mimetic traits are costly to express, or mimics are related to their neighbors, context-dependent discrimination can dramatically alter the outcome of mimetic evolution. We discuss context-dependent discrimination among signal receivers in relation to small-scale synchrony in model and mimic activity patterns.

Racialized customer service in restaurants: a quantitative assessment of the statistical discrimination explanatory framework.

PubMed

Brewster, Zachary W

2012-01-01

Despite popular claims that racism and discrimination are no longer salient issues in contemporary society, racial minorities continue to experience disparate treatment in everyday public interactions. The context of full-service restaurants is one such public setting wherein racial minority patrons, African Americans in particular, encounter racial prejudices and discriminate treatment. To further understand the causes of such discriminate treatment within the restaurant context, this article analyzes primary survey data derived from a community sample of servers (N = 200) to assess the explanatory power of one posited explanation—statistical discrimination. Taken as a whole, findings suggest that while a statistical discrimination framework toward understanding variability in servers’ discriminatory behaviors should not be disregarded, the framework’s explanatory utility is limited. Servers’ inferences about the potential profitability of waiting on customers across racial groups explain little of the overall variation in subjects’ self-reported discriminatory behaviors, thus suggesting that other factors not explored in this research are clearly operating and should be the focus of future inquires.

Perceptual Discrimination in Static and Dynamic Noise: The Temporal Relation between Perceptual Encoding and Decision Making

ERIC Educational Resources Information Center

Ratcliff, Roger; Smith, Philip L.

2010-01-01

The authors report 9 new experiments and reanalyze 3 published experiments that investigate factors affecting the time course of perceptual processing and its effects on subsequent decision making. Stimuli in letter-discrimination and brightness-discrimination tasks were degraded with static and dynamic noise. The onset and the time course of…

The asparagine-transamidosome from Helicobacter pylori: a dual-kinetic mode in non-discriminating aspartyl-tRNA synthetase safeguards the genetic code

PubMed Central

Fischer, Frédéric; Huot, Jonathan L.; Lorber, Bernard; Diss, Guillaume; Hendrickson, Tamara L.; Becker, Hubert D.; Lapointe, Jacques; Kern, Daniel

2012-01-01

Helicobacter pylori catalyzes Asn-tRNAAsn formation by use of the indirect pathway that involves charging of Asp onto tRNAAsn by a non-discriminating aspartyl-tRNA synthetase (ND-AspRS), followed by conversion of the mischarged Asp into Asn by the GatCAB amidotransferase. We show that the partners of asparaginylation assemble into a dynamic Asn-transamidosome, which uses a different strategy than the Gln-transamidosome to prevent the release of the mischarged aminoacyl-tRNA intermediate. The complex is described by gel-filtration, dynamic light scattering and kinetic measurements. Two strategies for asparaginylation are shown: (i) tRNAAsn binds GatCAB first, allowing aminoacylation and immediate transamidation once ND-AspRS joins the complex; (ii) tRNAAsn is bound by ND-AspRS which releases the Asp-tRNAAsn product much slower than the cognate Asp-tRNAAsp; this kinetic peculiarity allows GatCAB to bind and transamidate Asp-tRNAAsn before its release by the ND-AspRS. These results are discussed in the context of the interrelation between the Asn and Gln-transamidosomes which use the same GatCAB in H. pylori, and shed light on a kinetic mechanism that ensures faithful codon reassignment for Asn. PMID:22362756

The asparagine-transamidosome from Helicobacter pylori: a dual-kinetic mode in non-discriminating aspartyl-tRNA synthetase safeguards the genetic code.

PubMed

Fischer, Frédéric; Huot, Jonathan L; Lorber, Bernard; Diss, Guillaume; Hendrickson, Tamara L; Becker, Hubert D; Lapointe, Jacques; Kern, Daniel

2012-06-01

Helicobacter pylori catalyzes Asn-tRNA(Asn) formation by use of the indirect pathway that involves charging of Asp onto tRNA(Asn) by a non-discriminating aspartyl-tRNA synthetase (ND-AspRS), followed by conversion of the mischarged Asp into Asn by the GatCAB amidotransferase. We show that the partners of asparaginylation assemble into a dynamic Asn-transamidosome, which uses a different strategy than the Gln-transamidosome to prevent the release of the mischarged aminoacyl-tRNA intermediate. The complex is described by gel-filtration, dynamic light scattering and kinetic measurements. Two strategies for asparaginylation are shown: (i) tRNA(Asn) binds GatCAB first, allowing aminoacylation and immediate transamidation once ND-AspRS joins the complex; (ii) tRNA(Asn) is bound by ND-AspRS which releases the Asp-tRNA(Asn) product much slower than the cognate Asp-tRNA(Asp); this kinetic peculiarity allows GatCAB to bind and transamidate Asp-tRNA(Asn) before its release by the ND-AspRS. These results are discussed in the context of the interrelation between the Asn and Gln-transamidosomes which use the same GatCAB in H. pylori, and shed light on a kinetic mechanism that ensures faithful codon reassignment for Asn.

Acquisition of Social Referencing via Discrimination Training in Infants

ERIC Educational Resources Information Center

Pelaez, Martha; Virues-Ortega, Javier; Gewirtz, Jacob L.

2012-01-01

This experiment investigated social referencing as a form of discriminative learning in which maternal facial expressions signaled the consequences of the infant's behavior in an ambiguous context. Eleven 4- and 5-month-old infants and their mothers participated in a discrimination-training procedure using an ABAB design. Different consequences…

Context Matters: Links between Neighborhood Discrimination, Neighborhood Cohesion and African American Adolescents' Adjustment

ERIC Educational Resources Information Center

Riina, Elizabeth M.; Martin, Anne; Gardner, Margo; Brooks-Gunn, Jeanne

2013-01-01

Racial discrimination has serious negative consequences for the adjustment of African American adolescents. Taking an ecological approach, this study examined the linkages between perceived racial discrimination within and outside of the neighborhood and urban adolescents' externalizing and internalizing behaviors, and tested whether neighborhood…

Periodic, Quasi-periodic and Chaotic Dynamics in Simple Gene Elements with Time Delays

PubMed Central

Suzuki, Yoko; Lu, Mingyang; Ben-Jacob, Eshel; Onuchic, José N.

2016-01-01

Regulatory gene circuit motifs play crucial roles in performing and maintaining vital cellular functions. Frequently, theoretical studies of gene circuits focus on steady-state behaviors and do not include time delays. In this study, the inclusion of time delays is shown to entirely change the time-dependent dynamics for even the simplest possible circuits with one and two gene elements with self and cross regulations. These elements can give rise to rich behaviors including periodic, quasi-periodic, weak chaotic, strong chaotic and intermittent dynamics. We introduce a special power-spectrum-based method to characterize and discriminate these dynamical modes quantitatively. Our simulation results suggest that, while a single negative feedback loop of either one- or two-gene element can only have periodic dynamics, the elements with two positive/negative feedback loops are the minimalist elements to have chaotic dynamics. These elements typically have one negative feedback loop that generates oscillations, and another unit that allows frequent switches among multiple steady states or between oscillatory and non-oscillatory dynamics. Possible dynamical features of several simple one- and two-gene elements are presented in details. Discussion is presented for possible roles of the chaotic behavior in the robustness of cellular functions and diseases, for example, in the context of cancer. PMID:26876008

Periodic, Quasi-periodic and Chaotic Dynamics in Simple Gene Elements with Time Delays

NASA Astrophysics Data System (ADS)

Suzuki, Yoko; Lu, Mingyang; Ben-Jacob, Eshel; Onuchic, José N.

2016-02-01

Regulatory gene circuit motifs play crucial roles in performing and maintaining vital cellular functions. Frequently, theoretical studies of gene circuits focus on steady-state behaviors and do not include time delays. In this study, the inclusion of time delays is shown to entirely change the time-dependent dynamics for even the simplest possible circuits with one and two gene elements with self and cross regulations. These elements can give rise to rich behaviors including periodic, quasi-periodic, weak chaotic, strong chaotic and intermittent dynamics. We introduce a special power-spectrum-based method to characterize and discriminate these dynamical modes quantitatively. Our simulation results suggest that, while a single negative feedback loop of either one- or two-gene element can only have periodic dynamics, the elements with two positive/negative feedback loops are the minimalist elements to have chaotic dynamics. These elements typically have one negative feedback loop that generates oscillations, and another unit that allows frequent switches among multiple steady states or between oscillatory and non-oscillatory dynamics. Possible dynamical features of several simple one- and two-gene elements are presented in details. Discussion is presented for possible roles of the chaotic behavior in the robustness of cellular functions and diseases, for example, in the context of cancer.

The Trajectory of Coparenting Satisfaction in African American Families: The Impact of Sociocultural Stressors and Supports

PubMed Central

Riina, Elizabeth M.; McHale, Susan M.

2013-01-01

Based in family systems and ecological perspectives, this study expands the scope of coparenting research by: (a) charting the trajectory of coparenting satisfaction for mothers and fathers in two-parent African American families during their offspring's adolescence, and (b) examining the role of sociocultural stressors and supports for coparenting satisfaction. Participants were 192 African American mothers and fathers who reported on their coparenting satisfaction and both economic and cultural stressors (economic strain and racial discrimination), and supports (socioeconomic resources and religiosity). Longitudinal growth curves revealed declines in coparenting satisfaction for fathers but not mothers over the course of offspring's adolescence. Findings were generally consistent with hypotheses that stressors were negatively, and supports, positively, related to average levels of coparenting satisfaction. Findings for racial discrimination and income differed by parent and highlighted gender dynamics within couple relationships. We discuss implications for understanding of normative family processes in African American families as these unfold within both family and broader sociocultural contexts. PMID:23066677

Word Importance Discrimination using Context Information

DTIC Science & Technology

2008-11-01

Word importance discrimination using context information Danil Nemirovskya,b and Vladimir Dobryninb aINRIA Sophia Antipolis, France bSt. Petersburg...information 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7...PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) INRIA,Sophia Antipolis, France , 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING

Evaluating dedicated and intrinsic models of temporal encoding by varying context

PubMed Central

Spencer, Rebecca M.C.; Karmarkar, Uma; Ivry, Richard B.

2009-01-01

Two general classes of models have been proposed to account for how people process temporal information in the milliseconds range. Dedicated models entail a mechanism in which time is explicitly encoded; examples include clock–counter models and functional delay lines. Intrinsic models, such as state-dependent networks (SDN), represent time as an emergent property of the dynamics of neural processing. An important property of SDN is that the encoding of duration is context dependent since the representation of an interval will vary as a function of the initial state of the network. Consistent with this assumption, duration discrimination thresholds for auditory intervals spanning 100 ms are elevated when an irrelevant tone is presented at varying times prior to the onset of the test interval. We revisit this effect in two experiments, considering attentional issues that may also produce such context effects. The disruptive effect of a variable context was eliminated or attenuated when the intervals between the irrelevant tone and test interval were made dissimilar or the duration of the test interval was increased to 300 ms. These results indicate how attentional processes can influence the perception of brief intervals, as well as point to important constraints for SDN models. PMID:19487188

A review of statistical updating methods for clinical prediction models.

PubMed

Su, Ting-Li; Jaki, Thomas; Hickey, Graeme L; Buchan, Iain; Sperrin, Matthew

2018-01-01

A clinical prediction model is a tool for predicting healthcare outcomes, usually within a specific population and context. A common approach is to develop a new clinical prediction model for each population and context; however, this wastes potentially useful historical information. A better approach is to update or incorporate the existing clinical prediction models already developed for use in similar contexts or populations. In addition, clinical prediction models commonly become miscalibrated over time, and need replacing or updating. In this article, we review a range of approaches for re-using and updating clinical prediction models; these fall in into three main categories: simple coefficient updating, combining multiple previous clinical prediction models in a meta-model and dynamic updating of models. We evaluated the performance (discrimination and calibration) of the different strategies using data on mortality following cardiac surgery in the United Kingdom: We found that no single strategy performed sufficiently well to be used to the exclusion of the others. In conclusion, useful tools exist for updating existing clinical prediction models to a new population or context, and these should be implemented rather than developing a new clinical prediction model from scratch, using a breadth of complementary statistical methods.

Acoustic variability within and across German, French, and American English vowels: phonetic context effects.

PubMed

Strange, Winifred; Weber, Andrea; Levy, Erika S; Shafiro, Valeriy; Hisagi, Miwako; Nishi, Kanae

2007-08-01

Cross-language perception studies report influences of speech style and consonantal context on perceived similarity and discrimination of non-native vowels by inexperienced and experienced listeners. Detailed acoustic comparisons of distributions of vowels produced by native speakers of North German (NG), Parisian French (PF) and New York English (AE) in citation (di)syllables and in sentences (surrounded by labial and alveolar stops) are reported here. Results of within- and cross-language discriminant analyses reveal striking dissimilarities across languages in the spectral/temporal variation of coarticulated vowels. As expected, vocalic duration was most important in differentiating NG vowels; it did not contribute to PF vowel classification. Spectrally, NG long vowels showed little coarticulatory change, but back/low short vowels were fronted/raised in alveolar context. PF vowels showed greater coarticulatory effects overall; back and front rounded vowels were fronted, low and mid-low vowels were raised in both sentence contexts. AE mid to high back vowels were extremely fronted in alveolar contexts, with little change in mid-low and low long vowels. Cross-language discriminant analyses revealed varying patterns of spectral (dis)similarity across speech styles and consonantal contexts that could, in part, account for AE listeners' perception of German and French front rounded vowels, and "similar" mid-high to mid-low vowels.

Gloss discrimination and eye movements

NASA Astrophysics Data System (ADS)

Phillips, Jonathan B.; Ferwerda, James A.; Nunziata, Ann

2010-02-01

Human observers are able to make fine discriminations of surface gloss. What cues are they using to perform this task? In previous studies, we identified two reflection-related cues-the contrast of the reflected image (c, contrast gloss) and the sharpness of reflected image (d, distinctness-of-image gloss)--but these were for objects rendered in standard dynamic range (SDR) images with compressed highlights. In ongoing work, we are studying the effects of image dynamic range on perceived gloss, comparing high dynamic range (HDR) images with accurate reflections and SDR images with compressed reflections. In this paper, we first present the basic findings of this gloss discrimination study then present an analysis of eye movement recordings that show where observers were looking during the gloss discrimination task. The results indicate that: 1) image dynamic range has significant influence on perceived gloss, with surfaces presented in HDR images being seen as glossier and more discriminable than their SDR counterparts; 2) observers look at both light source highlights and environmental interreflections when judging gloss; and 3) both of these results are modulated by surface geometry and scene illumination.

Neural mechanisms of coarse-to-fine discrimination in the visual cortex.

PubMed

Purushothaman, Gopathy; Chen, Xin; Yampolsky, Dmitry; Casagrande, Vivien A

2014-12-01

Vision is a dynamic process that refines the spatial scale of analysis over time, as evidenced by a progressive improvement in the ability to detect and discriminate finer details. To understand coarse-to-fine discrimination, we studied the dynamics of spatial frequency (SF) response using reverse correlation in the primary visual cortex (V1) of the primate. In a majority of V1 cells studied, preferred SF either increased monotonically with time (group 1) or changed nonmonotonically, with an initial increase followed by a decrease (group 2). Monotonic shift in preferred SF occurred with or without an early suppression at low SFs. Late suppression at high SFs always accompanied nonmonotonic SF dynamics. Bayesian analysis showed that SF discrimination performance and best discriminable SF frequencies changed with time in different ways in the two groups of neurons. In group 1 neurons, SF discrimination performance peaked on both left and right flanks of the SF tuning curve at about the same time. In group 2 neurons, peak discrimination occurred on the right flank (high SFs) later than on the left flank (low SFs). Group 2 neurons were also better discriminators of high SFs. We examined the relationship between the time at which SF discrimination performance peaked on either flank of the SF tuning curve and the corresponding best discriminable SFs in both neuronal groups. This analysis showed that the population best discriminable SF increased with time in V1. These results suggest neural mechanisms for coarse-to-fine discrimination behavior and that this process originates in V1 or earlier. Copyright © 2014 the American Physiological Society.

Discrimination Concerns and Expectations as Explanations for Gendered Socialization in African American Families

ERIC Educational Resources Information Center

Varner, Fatima; Mandara, Jelani

2013-01-01

Discrimination concerns and parental expectations were examined as mediators of the relations between gender and parenting practices among 796 African American mothers of 11- to 14-year-olds from the Maryland Adolescent Development in Context Study. Mothers of sons had more concerns about racial discrimination impacting their adolescents' future,…

Psychoacoustic Assessment of Speech Communication Systems. The Diagnostic Discrimination Test.

ERIC Educational Resources Information Center

Grether, Craig Blaine

The present report traces the rationale, development and experimental evaluation of the Diagnostic Discrimination Test (DDT). The DDT is a three-choice test of consonant discriminability of the perceptual/acoustic dimensions of consonant phonemes within specific vowel contexts. The DDT was created and developed in an attempt to provide a…

Dispositional Hardiness and Women's Well-Being Relating to Gender Discrimination: The Role of Minimization

ERIC Educational Resources Information Center

Foster, Mindi D.; Dion, Kenneth L.

2003-01-01

Three studies examined whether personality-based hardiness would be associated with mental health benefits in contexts of gender discrimination. Hardy women encountering both a laboratory simulation and a hypothetical scenario of discrimination showed greater self-esteem and less negative affect than low hardy women. However, these benefits were…

School and Neighborhood Contexts, Perceptions of Racial Discrimination, and Psychological Well-Being among African American Adolescents

ERIC Educational Resources Information Center

Seaton, Eleanor K.; Yip, Tiffany

2009-01-01

The present study examined contextual influences on the relationship between racial discrimination (individual, cultural, and collective/institutional) and psychological well-being. Two hundred and fifty two African American adolescents (46% male and 54% female, average age = 16) completed measures of racial discrimination, self-esteem, depressive…

Social Support as a Buffer Between Discrimination and Cigarette Use in Juvenile Offenders

PubMed Central

Hershberger, Alexandra; Zapolski, Tamika; Aalsma, Matthew C.

2016-01-01

Cigarette use is a prominent problem in juvenile offenders, leading to negative health outcomes and substance use. One interesting precipitator of cigarette use in this population is discrimination. Social support could potentially buffer the positive relationship between cigarette use and discrimination in juvenile offenders, which could be dependent on the context in which the discrimination is experienced, such as peer, institutional (e.g., stores, restaurants), or educational contexts. The present study explored the relationship between three types of discrimination, social support, and smoking outcomes among 112 detained and probated juvenile offenders (mean age = 16.24, SD = 2.11, 29.2% female, 54.9% Caucasian, 40.4% detention, 53.8% smokers). Results indicated that the relationship between institutional discrimination (OR = −0.10, p = 0.005) and peer discrimination (OR = −0.11, p = 0.01) were significantly moderated by social support, with a higher likelihood of being a smoker, compared to a non-smoker at higher levels of peer and institutional discrimination. Further, based on a moderated regression analysis, results indicated that youth who experienced greater educational discrimination and lower levels of social support, they were at higher risk of nicotine addiction (b = −0.09, p = 0.03). Overall, results indicate that varying avenues of social support, such as parent, peer, and teacher support, can mitigate negative effects of discrimination on juvenile offenders, particularly cigarette use. Addressing discrimination in smoking treatment and prevention in juvenile offenders may be of great utility. Future studies should examine the potential mechanisms underlying the discrimination and cigarette use connection in juvenile offenders. PMID:27010849

Social support as a buffer between discrimination and cigarette use in juvenile offenders.

PubMed

Hershberger, Alexandra; Zapolski, Tamika; Aalsma, Matthew C

2016-08-01

Cigarette use is a prominent problem in juvenile offenders, leading to negative health outcomes and substance use. One interesting precipitator of cigarette use in this population is discrimination. Social support could potentially buffer the positive relationship between cigarette use and discrimination in juvenile offenders, which could be dependent on the context in which the discrimination is experienced, such as peer, institutional (e.g., stores, restaurants), or educational contexts. The present study explored the relationship between three types of discrimination, social support, and smoking outcomes among 112 detained and probated juvenile offenders (mean age=16.24, SD=2.11, 29.2% female, 54.9% Caucasian, 40.4% detention, 53.8% smokers). Results indicated that the relationship between institutional discrimination (OR=-0.10, p=0.005) and peer discrimination (OR=-0.11, p=0.01) were significantly moderated by social support, with a higher likelihood of being a smoker, compared to a non-smoker at higher levels of peer and institutional discrimination. Further, based on a moderated regression analysis, results indicated that youth who experienced greater educational discrimination and lower levels of social support, they were at higher risk of nicotine addiction (b=-0.09, p=0.03). Overall, results indicate that varying avenues of social support, such as parent, peer, and teacher support, can mitigate negative effects of discrimination on juvenile offenders, particularly cigarette use. Addressing discrimination in smoking treatment and prevention in juvenile offenders may be of great utility. Future studies should examine the potential mechanisms underlying the discrimination and cigarette use connection in juvenile offenders. Copyright © 2016 Elsevier Ltd. All rights reserved.

Conformational and chemical selection by a trans-acting editing domain

PubMed Central

Danhart, Eric M.; Bakhtina, Marina; Cantara, William A.; Kuzmishin, Alexandra B.; Ma, Xiao; Sanford, Brianne L.; Vargas-Rodriguez, Oscar; Košutić, Marija; Goto, Yuki; Suga, Hiroaki; Nakanishi, Kotaro; Micura, Ronald; Musier-Forsyth, Karin

2017-01-01

Molecular sieves ensure proper pairing of tRNAs and amino acids during aminoacyl-tRNA biosynthesis, thereby avoiding detrimental effects of mistranslation on cell growth and viability. Mischarging errors are often corrected through the activity of specialized editing domains present in some aminoacyl-tRNA synthetases or via single-domain trans-editing proteins. ProXp-ala is a ubiquitous trans-editing enzyme that edits Ala-tRNAPro, the product of Ala mischarging by prolyl-tRNA synthetase, although the structural basis for discrimination between correctly charged Pro-tRNAPro and mischarged Ala-tRNAAla is unclear. Deacylation assays using substrate analogs reveal that size discrimination is only one component of selectivity. We used NMR spectroscopy and sequence conservation to guide extensive site-directed mutagenesis of Caulobacter crescentus ProXp-ala, along with binding and deacylation assays to map specificity determinants. Chemical shift perturbations induced by an uncharged tRNAPro acceptor stem mimic, microhelixPro, or a nonhydrolyzable mischarged Ala-microhelixPro substrate analog identified residues important for binding and deacylation. Backbone 15N NMR relaxation experiments revealed dynamics for a helix flanking the substrate binding site in free ProXp-ala, likely reflecting sampling of open and closed conformations. Dynamics persist on binding to the uncharged microhelix, but are attenuated when the stably mischarged analog is bound. Computational docking and molecular dynamics simulations provide structural context for these findings and predict a role for the substrate primary α-amine group in substrate recognition. Overall, our results illuminate strategies used by a trans-editing domain to ensure acceptance of only mischarged Ala-tRNAPro, including conformational selection by a dynamic helix, size-based exclusion, and optimal positioning of substrate chemical groups. PMID:28768811

Discrimination and Depression among Urban Hispanics with Poorly Controlled Diabetes

PubMed Central

March, Dana; Williams, Jasmine; Wells, Shayla; Eimicke, Joseph P.; Teresi, Jeanne A.; Almonte, Casandra; Link, Bruce G.; Findley, Sally E.; Palmas, Walter; Carrasquillo, Olveen; Luchsinger, José A.

2017-01-01

Objectives We had three objectives for our study: 1) to describe the prevalence and burden of experiences of discrimination among Hispanics with poorly controlled diabetes; 2) to evaluate associations among discrimination experiences and their burden with comorbid depression among Hispanics with poorly controlled diabetes; and 3) to evaluate whether discrimination encountered in the health care context itself was associated with comorbid depression for Hispanic adults with diabetes. Design We conducted a cross-sectional analysis of baseline data of a randomized controlled trial (RCT). Setting We collected data in the context of an RCT in a clinical setting in New York City. Participants Our sample comprised 221 urban-dwelling Hispanics, largely of Caribbean origin. Main Outcome Measures The main outcome measure was major depression, measured by the Euro-D (score>3). Results Of 221 participants, 58.8% reported at least one experience of everyday discrimination, and 42.5% reported at least one major experience of discrimination. Depression was associated significantly with counts of experiences of major discrimination (OR=1.46, 95% CI=1.09-1.94, P=.01), aggregate counts of everyday and major discrimination (OR=1.13, 95%CI=1.02-1.26, P=.02),andtheexperienceofdiscrimination in getting care for physical health (OR=6.30, 95%CI=1.10-36.03). Conclusions Discrimination may pose a barrier to getting health care and may be associated with depression among Hispanics with diabetes. Clinicians treating Caribbean-born Hispanics should be aware that disadvantage and discrimination likely complicate a presentation of diabetes. PMID:26118138

New developments in the law for obesity discrimination protection.

PubMed

Pomeranz, Jennifer L; Puhl, Rebecca M

2013-03-01

Obese individuals are frequent targets of weight-based discrimination, particularly in the employment setting. Victims of weight discrimination have sought legal restitution like others who have suffered from different forms of discrimination. However, in the vast majority of the United States, body weight is not a protected class and weight-based employment discrimination does not provide a basis for a legal claim. Some have attempted to seek legal recourse under the Rehabilitation Act of 1973 or the Americans with Disabilities Act of 1990 (collectively, the ADA), which protect against discrimination based on mental or physical disabilities in a variety of settings. Until recently, claims of weight discrimination under the ADA have also been largely unsuccessful. However, Congress recently passed the ADA Amendments Act, expanding the definition of what constitutes a disability and incorporating a broad view of ADA's coverage. This short communication provides an update of the law as it relates to employment based discrimination of obese people. The authors propose a legislative direction for future legal recourse. The authors conducted legal research into the ADA Amendments Act, and synthesized this work relating to discrimination against weight in the employment context. In light of the ADA Amendments Act, courts and the Equal Employment Opportunity Commission have provided protection for severely obese people from discrimination based on actual or perceived disability in the employment context. The authors discuss this positive legal development and additionally propose a targeted solution to address weight discrimination in the employment setting. National polling suggests there is considerable public support for such a measure. The authors thus recommend the implementation of a "Weight Discrimination in Employment Act" modeled after the Age Discrimination in Employment Act to adequately address this pervasive and damaging injustice toward individuals who are affected by obesity. Copyright © 2013 The Obesity Society.

Contextual Control of Fluid Consumption: The Effects of Context Extinction

ERIC Educational Resources Information Center

Murphy, M.; Skinner, D.M.

2005-01-01

Rats were trained on a conditional discrimination task in which saccharin was paired with LiCl in one context but paired with saline in another context. Rats drank less saccharin in the danger context than in the safe context, and consumption in the home cage was intermediate to consumption in the two training contexts. Rats also avoided the…

Temporal characteristics of the influence of punishment on perceptual decision making in the human brain.

PubMed

Blank, Helen; Biele, Guido; Heekeren, Hauke R; Philiastides, Marios G

2013-02-27

Perceptual decision making is the process by which information from sensory systems is combined and used to influence our behavior. In addition to the sensory input, this process can be affected by other factors, such as reward and punishment for correct and incorrect responses. To investigate the temporal dynamics of how monetary punishment influences perceptual decision making in humans, we collected electroencephalography (EEG) data during a perceptual categorization task whereby the punishment level for incorrect responses was parametrically manipulated across blocks of trials. Behaviorally, we observed improved accuracy for high relative to low punishment levels. Using multivariate linear discriminant analysis of the EEG, we identified multiple punishment-induced discriminating components with spatially distinct scalp topographies. Compared with components related to sensory evidence, components discriminating punishment levels appeared later in the trial, suggesting that punishment affects primarily late postsensory, decision-related processing. Crucially, the amplitude of these punishment components across participants was predictive of the size of the behavioral improvements induced by punishment. Finally, trial-by-trial changes in prestimulus oscillatory activity in the alpha and gamma bands were good predictors of the amplitude of these components. We discuss these findings in the context of increased motivation/attention, resulting from increases in punishment, which in turn yields improved decision-related processing.

Racial/Ethnic Discrimination and Adolescents' Well-Being: The Role of Cross-Ethnic Friendships and Friends' Experiences of Discrimination

ERIC Educational Resources Information Center

Benner, Aprile D.; Wang, Yijie

2017-01-01

There is an extensive body of work documenting the negative socioemotional and academic consequences of perceiving racial/ethnic discrimination during adolescence, but little is known about how the larger peer context conditions such effects. Using peer network data from 252 eighth graders (85% Latino, 11% African American, 5% other…

Ethnic Discrimination against Mapuche Students in Urban High Schools in the Araucanía Region, Chile

ERIC Educational Resources Information Center

Becerra, Sandra; Merino, María Eugenia; Mellor, David

2015-01-01

Ethnic or racial discrimination towards children and adolescents at schools is of concern in many contexts around the world because it is associated with diverse psychosocial, behavioural, emotional, and identity problems. The purpose of this study was to identify the types of ethnic discrimination experienced by indigenous Mapuche adolescents in…

Extinction and Renewal of Pavlovian Modulation in Human Sequential Feature Positive Discrimination Learning

ERIC Educational Resources Information Center

Baeyens, Frank; Vansteenwegen, Debora; Beckers, Tom; Hermans, Dirk; Kerkhof, Ineke; De Ceulaer, Annick

2005-01-01

Using a conditioned suppression task, we investigated extinction and renewal of Pavlovian modulation in human sequential Feature Positive (FP) discrimination learning. In Experiment 1, in context a participants were first trained on two FP discriminations, X[right arrow]A+/A- and Y[right arrow]B+/B-. Extinction treatment was administered in the…

Remote sensing of a dynamic sub-arctic peatland reservoir using optical and synthetic aperture radar data

NASA Astrophysics Data System (ADS)

Larter, Jarod Lee

Stephens Lake, Manitoba is an example of a peatland reservoir that has undergone physical changes related to mineral erosion and peatland disintegration processes since its initial impoundment. In this thesis I focused on the processes of peatland upheaval, transport, and disintegration as the primary drivers of dynamic change within the reservoir. The changes related to these processes are most frequent after initial reservoir impoundment and decline over time. They continue to occur over 35 years after initial flooding. I developed a remote sensing approach that employs both optical and microwave sensors for discriminating land (Le. floating peatlands, forested land, and barren land) from open water within the reservoir. High spatial resolution visible and near-infrared (VNIR) optical data obtained from the QuickBird satellite, and synthetic aperture radar (SAR) microwave data obtained from the RADARSAT-1 satellite were implemented. The approach was facilitated with a Geographic Information System (GIS) based validation map for the extraction of optical and SAR pixel data. Each sensor's extracted data set was first analyzed separately using univariate and multivariate statistical methods to determine the discriminant ability of each sensor. The initial analyses were followed by an integrated sensor approach; the development of an image classification model; and a change detection analysis. Results showed excellent (> 95%) classification accuracy using QuickBird satellite image data. Discrimination and classification of studied land cover classes using SAR image texture data resulted in lower overall classification accuracies (˜ 60%). SAR data classification accuracy improved to > 90% when classifying only land and water, demonstrating SAR's utility as a land and water mapping tool. An integrated sensor data approach showed no considerable improvement over the use of optical satellite image data alone. An image classification model was developed that could be used to map both detailed land cover classes and the land and water interface within the reservoir. Change detection analysis over a seven year period indicated that physical changes related to mineral erosion, peatland upheaval, transport, and disintegration, and operational water level variation continue to take place in the reservoir some 35 years after initial flooding. This thesis demonstrates the ability of optical and SAR satellite image remote sensing data sets to be used in an operational context for the routine discrimination of the land and water boundaries within a dynamic peatland reservoir. Future monitoring programs would benefit most from a complementary image acquisition program in which SAR images, known for their acquisition reliability under cloud cover, are acquired along with optical images given their ability to discriminate land cover classes in greater detail.

Inequality dynamics in the workplace among microbiologists and infectious disease specialists: a qualitative study in five European countries.

PubMed

Huttner, A; Cacace, M; d'Andrea, L; Skevaki, C; Otelea, D; Pugliese, F; Tacconelli, E

2017-05-01

To explore the social, cultural, psychological and organizational factors associated with inequality in the workplace among clinical microbiologists (CM) and infectious disease (ID) specialists in European hospitals. We analysed data from 52 interviews and five focus groups involving 82 CM/ID specialists selected from university, research or community hospitals in five countries, one each in Northern, Western, Eastern, Southeastern and Southwestern Europe. The 80 hours of recordings were transcribed, and the anonymous database coding process was cross-checked iteratively by six researchers. Inequality affects all the institutions in all the countries we looked at, denying or reducing access to professional assets with intensity and form that vary largely according to the cultural and organizational context. Discrimination is generally not explicit and uses disrespectful microbehaviours that are hard to respond to when they occur. Inequality affected also loans, distribution of research funds and gender and country representation in boards and conference faculty. Parenthood has a major impact on women's careers, as women are still mainly responsible for family care. Responses to discrimination range from reactive to surrender strategies. Our study offers an effective model for diagnosing discriminatory behaviours in a medical professional setting. Knowledge of inequality's drivers could help national ID/CM societies in collaboration with major European stakeholders to further reduce such discrimination. The effect of discrimination on the quality of healthcare in Europe needs further exploration. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Neuronal Assemblies Evidence Distributed Interactions within a Tactile Discrimination Task in Rats

PubMed Central

Deolindo, Camila S.; Kunicki, Ana C. B.; da Silva, Maria I.; Lima Brasil, Fabrício; Moioli, Renan C.

2018-01-01

Accumulating evidence suggests that neural interactions are distributed and relate to animal behavior, but many open questions remain. The neural assembly hypothesis, formulated by Hebb, states that synchronously active single neurons may transiently organize into functional neural circuits—neuronal assemblies (NAs)—and that would constitute the fundamental unit of information processing in the brain. However, the formation, vanishing, and temporal evolution of NAs are not fully understood. In particular, characterizing NAs in multiple brain regions over the course of behavioral tasks is relevant to assess the highly distributed nature of brain processing. In the context of NA characterization, active tactile discrimination tasks with rats are elucidative because they engage several cortical areas in the processing of information that are otherwise masked in passive or anesthetized scenarios. In this work, we investigate the dynamic formation of NAs within and among four different cortical regions in long-range fronto-parieto-occipital networks (primary somatosensory, primary visual, prefrontal, and posterior parietal cortices), simultaneously recorded from seven rats engaged in an active tactile discrimination task. Our results first confirm that task-related neuronal firing rate dynamics in all four regions is significantly modulated. Notably, a support vector machine decoder reveals that neural populations contain more information about the tactile stimulus than the majority of single neurons alone. Then, over the course of the task, we identify the emergence and vanishing of NAs whose participating neurons are shown to contain more information about animal behavior than randomly chosen neurons. Taken together, our results further support the role of multiple and distributed neurons as the functional unit of information processing in the brain (NA hypothesis) and their link to active animal behavior. PMID:29375324

Impaired contextual fear-conditioning in MAM rodent model of schizophrenia.

PubMed

Gill, Kathryn M; Miller, Sarah A; Grace, Anthony A

2018-05-01

The methylazoxymethanol acetate (MAM) rodent neurodevelopmental model of schizophrenia exhibits aberrant dopamine system activation attributed to hippocampal dysfunction. Context discrimination is a component of numerous behavioral and cognitive functions and relies on intact hippocampal processing. The present study explored context processing behaviors, along with dopamine system activation, during fear learning in the MAM model. Male offspring of dams treated with MAM (20mg/kg, i.p.) or saline on gestational day 17 were used for electrophysiological and behavioral experiments. Animals were tested on the immediate shock fear conditioning paradigm, with either different pre-conditioning contexts or varying amounts of context pre-exposure (0-10 sessions). Amphetamine-induced locomotor activity and dopamine neural activity was measured 1-week after fear conditioning. Saline, but not MAM animals, demonstrated enhanced fear responses following a single context pre-exposure in the conditioning context. One week following fear learning, saline rats with 2 or 7min of context pre-exposure prior to fear conditioning also demonstrated enhanced amphetamine-induced locomotor response relative to MAM animals. Dopamine neuron recordings showed fear learning-induced reductions in spontaneous dopamine neural activity in MAM rats that was further reduced by amphetamine. Apomorphine administration confirmed that reductions in dopamine neuron activity in MAM animals resulted from over excitation, or depolarization block. These data show a behavioral insensitivity to contextual stimuli in MAM rats that coincide with a less dynamic dopamine response after fear learning. Copyright © 2017 Elsevier B.V. All rights reserved.

Recognition of visual stimuli and memory for spatial context in schizophrenic patients and healthy volunteers.

PubMed

Brébion, Gildas; David, Anthony S; Pilowsky, Lyn S; Jones, Hugh

2004-11-01

Verbal and visual recognition tasks were administered to 40 patients with schizophrenia and 40 healthy comparison subjects. The verbal recognition task consisted of discriminating between 16 target words and 16 new words. The visual recognition task consisted of discriminating between 16 target pictures (8 black-and-white and 8 color) and 16 new pictures (8 black-and-white and 8 color). Visual recognition was followed by a spatial context discrimination task in which subjects were required to remember the spatial location of the target pictures at encoding. Results showed that recognition deficit in patients was similar for verbal and visual material. In both schizophrenic and healthy groups, men, but not women, obtained better recognition scores for the colored than for the black-and-white pictures. However, men and women similarly benefited from color to reduce spatial context discrimination errors. Patients showed a significant deficit in remembering the spatial location of the pictures, independently of accuracy in remembering the pictures themselves. These data suggest that patients are impaired in the amount of visual information that they can encode. With regards to the perceptual attributes of the stimuli, memory for spatial information appears to be affected, but not processing of color information.

A dangerous context changes the way that rats learn about and discriminate between innocuous events in sensory preconditioning.

PubMed

Holmes, Nathan M; Westbrook, R Frederick

2017-09-01

Four experiments used a sensory preconditioning protocol to examine how a dangerous context influences learning about innocuous events. In Experiments 1, 2, and 3, rats were exposed to presentations of a tone followed immediately or 20-sec later by presentations of a light. These tone-light pairings occurred in a context that was either familiar and safe, or equally familiar but dangerous, that is, it was a context in which rats had been exposed to footshock. Rats were next exposed to parings of the light and shock and then tested with the tone (and light). The experiments showed that a dangerous context permits formation of a tone-light association under circumstances that preclude formation of that same association in a safe context (Experiments 1 and 2), and that this facilitative effect on associative formation depends on the content being currently dangerous rather than having been dangerous in the past (Experiment 3). Experiment 4 examined whether a dangerous context facilitates discrimination between two innocuous events. In a safe or dangerous context, rats were exposed to a tone that signaled the light and then to a white noise presented alone. Subsequent to conditioning of the light, the tests revealed that rats that had been exposed to these tone-light and white noise alone presentations in a dangerous context froze to the tone but not to the noise, whereas those exposed in a safe context froze to both the tone and the white noise. The results were related to previous evidence that the amygdala is critical for processing information about innocuous stimuli in a dangerous but not a safe context. They were attributed to an amygdala-based enhancement of arousal and/or attention in a dangerous context, hence the facilitation of associative formation and enhanced discriminability in this context. © 2017 Holmes and Westbrook; Published by Cold Spring Harbor Laboratory Press.

Discrimination-related health inequality and role of social capital among marriage migrant women in South Korea.

PubMed

Kim, Chang-O

2016-10-26

This study aimed to evaluate whether social capital could alleviate health inequality against racial discrimination and identify the critical nature of social capital that generates health inequality differences within the social context of South Korea. Using the data of the 2009 National Survey of Multicultural Families, a nationally representative sample in which 40,430 foreign wives participated, the concentration index (CI) was used to measure the discrimination-related inequalities in self-rated health and was decomposed into contributing factors. The results showed a significant concentration of poor self-rated health unfavorable to foreign wives who were highly discriminated (CI 0.023, standard error [SE] 0.001, p < .001). However, when the CIs were assessed among the subgroups of different social capital, no discrimination-related inequality in health was observed among the group of linking social capital (CI 0.008, SE 0.008, p .332). The total differential decomposition method showed two major factors that generate differences in health inequality between the groups of non-linking and linking social capital: protest against discrimination (35.8 %); experiences of discrimination (28.3 %). The present results indicated that linking social capital can be a useful resource of health resilience factor that equalizes discrimination-related health inequality among marriage migrant women in South Korea. This study provides additional evidence that social capital needs to be placed in its political context.

S parameter and pseudo Nambu-Goldstone boson mass from lattice QCD.

PubMed

Shintani, E; Aoki, S; Fukaya, H; Hashimoto, S; Kaneko, T; Matsufuru, H; Onogi, T; Yamada, N

2008-12-12

We present a lattice calculation of L10, one of the low-energy constants in chiral perturbation theory, and the charged-neutral pion squared-mass splitting, using dynamical overlap fermion. The exact chiral symmetry of the overlap fermion allows us to reliably extract these quantities from the difference of the vacuum polarization functions for vector and axial-vector currents. In the context of the technicolor models, these two quantities are read as the S parameter and the pseudo Nambu-Goldstone boson mass, respectively, and play an important role in discriminating the models from others. This calculation can serve as a feasibility study of the lattice techniques for more general technicolor gauge theories.

Discrimination of correlated and entangling quantum channels with selective process tomography

DOE PAGES

Dumitrescu, Eugene; Humble, Travis S.

2016-10-10

The accurate and reliable characterization of quantum dynamical processes underlies efforts to validate quantum technologies, where discrimination between competing models of observed behaviors inform efforts to fabricate and operate qubit devices. We present a protocol for quantum channel discrimination that leverages advances in direct characterization of quantum dynamics (DCQD) codes. We demonstrate that DCQD codes enable selective process tomography to improve discrimination between entangling and correlated quantum dynamics. Numerical simulations show selective process tomography requires only a few measurement configurations to achieve a low false alarm rate and that the DCQD encoding improves the resilience of the protocol to hiddenmore » sources of noise. Lastly, our results show that selective process tomography with DCQD codes is useful for efficiently distinguishing sources of correlated crosstalk from uncorrelated noise in current and future experimental platforms.« less

The Antecedents and Consequences of Racial/Ethnic Discrimination during Adolescence: Does the Source of Discrimination Matter?

ERIC Educational Resources Information Center

Benner, Aprile D.; Graham, Sandra

2013-01-01

In the current study, we examined the precursors and consequences of discrimination for 876 Latino, African American, and Asian American adolescents (M[subscript age] = 16.9 years, SD = 0.43). The race/ethnic characteristics of schools and neighborhoods influenced adolescents' perceptions of the race/ethnic climates of these contexts. In turn,…

Contributions of individual face features to face discrimination.

PubMed

Logan, Andrew J; Gordon, Gael E; Loffler, Gunter

2017-08-01

Faces are highly complex stimuli that contain a host of information. Such complexity poses the following questions: (a) do observers exhibit preferences for specific information? (b) how does sensitivity to individual face parts compare? These questions were addressed by quantifying sensitivity to different face features. Discrimination thresholds were determined for synthetic faces under the following conditions: (i) 'full face': all face features visible; (ii) 'isolated feature': single feature presented in isolation; (iii) 'embedded feature': all features visible, but only one feature modified. Mean threshold elevations for isolated features, relative to full-faces, were 0.84x, 1.08, 2.12, 3.34, 4.07 and 4.47 for head-shape, hairline, nose, mouth, eyes and eyebrows respectively. Hence, when two full faces can be discriminated at threshold, the difference between the eyes is about four times less than what is required when discriminating between isolated eyes. In all cases, sensitivity was higher when features were presented in isolation than when they were embedded within a face context (threshold elevations of 0.94x, 1.74, 2.67, 2.90, 5.94 and 9.94). This reveals a specific pattern of sensitivity to face information. Observers are between two and four times more sensitive to external than internal features. The pattern for internal features (higher sensitivity for the nose, compared to mouth, eyes and eyebrows) is consistent with lower sensitivity for those parts affected by facial dynamics (e.g. facial expressions). That isolated features are easier to discriminate than embedded features supports a holistic face processing mechanism which impedes extraction of information about individual features from full faces. Copyright © 2017 Elsevier Ltd. All rights reserved.

Future directions in research on institutional and interpersonal discrimination and children's health.

PubMed

Acevedo-Garcia, Dolores; Rosenfeld, Lindsay E; Hardy, Erin; McArdle, Nancy; Osypuk, Theresa L

2013-10-01

Research evidence indicates that 2 forms of racial discrimination-perceived interpersonal discrimination and racial/ethnic residential segregation (a form of institutional discrimination)-may influence children's health and disparities. Although research on these 2 forms of discrimination and health has primarily focused on adults, smaller bodies of work have documented that perceived interpersonal discrimination and segregation have a negative effect on infants' health, and that perceived interpersonal discrimination may negatively affect children's mental health. Three directions for research are (1) incorporating a life-course perspective into studies of discrimination and children's health, (2) linking residential segregation with geography-of-opportunity conceptual frameworks and measures, and (3) considering residential segregation along with segregation in other contexts that influence children's health (e.g., schools).

(S)-citalopram influences amygdala modulation in healthy subjects: a randomized placebo-controlled double-blind fMRI study using dynamic causal modeling.

PubMed

Sladky, Ronald; Spies, Marie; Hoffmann, Andre; Kranz, Georg; Hummer, Allan; Gryglewski, Gregor; Lanzenberger, Rupert; Windischberger, Christian; Kasper, Siegfried

2015-03-01

Citalopram and Escitalopram are gold standard pharmaceutical treatment options for affective, anxiety, and other psychiatric disorders. However, their neurophysiologic function on cortico-limbic circuits is incompletely characterized. Here we studied the neuropharmacological influence of Citalopram and Escitalopram on cortico-limbic regulatory processes by assessing the effective connectivity between orbitofrontal cortex (OFC) and amygdala using dynamic causal modeling (DCM) applied to functional MRI data. We investigated a cohort of 15 healthy subjects in a randomized, crossover, double-blind design after 10days of Escitalopram (10mg/d (S)-citalopram), Citalopram (10mg/d (S)-citalopram and 10mg/d (R)-citalopram), or placebo. Subjects performed an emotional face discrimination task, while undergoing functional magnetic resonance imaging (fMRI) scanning at 3 Tesla. As hypothesized, the OFC, in the context of the emotional face discrimination task, exhibited a down-regulatory effect on amygdala activation. This modulatory effect was significantly increased by (S)-citalopram, but not (R)-citalopram. For the first time, this study shows that (1) the differential effects of the two enantiomers (S)- and (R)-citalopram on cortico-limbic connections can be demonstrated by modeling effective connectivity methods, and (2) one of their mechanisms can be linked to an increased inhibition of amygdala activation by the orbitofrontal cortex. Copyright © 2014 Elsevier Inc. All rights reserved.

Strength in numbers? Cognitive reappraisal tendencies and psychological functioning among Latinos in the context of oppression.

PubMed

Soto, José A; Armenta, Brian E; Perez, Christopher R; Zamboanga, Byron L; Umaña-Taylor, Adriana J; Lee, Richard M; Schwartz, Seth J; Park, Irene J K; Huynh, Que-Lam; Whitbourne, Susan Krauss; Le, Thao N; Ham, Lindsay S

2012-10-01

The typically positive relationship between cognitive reappraisal and psychological functioning may be nullified for Latinos embedded within multiple contexts of oppression (Perez & Soto, 2011). Multiply oppressive contexts are characterized by exposure to oppression at a societal level (distal oppression), in the immediate environment (proximal oppression), and at an individual level (personal oppression). We replicated and extended Perez and Soto's (2011) findings by examining whether the reappraisal-psychological functioning association was moderated by (a) relative numerical representation of Latinos within the environment (proximal oppression) and (b) personal perceptions of discrimination (personal oppression) among 425 Latino college students throughout the United States. For Latinos in high-Latino counties, greater use of reappraisal was associated with better psychological functioning, regardless of perceived discrimination; this relationship was absent for Latinos in low-Latino counties who perceived greater discrimination. Findings highlight the importance of considering how contextual factors can alter the adaptive functions of emotion regulation strategies.

Musically tone-deaf individuals have difficulty discriminating intonation contours extracted from speech.

PubMed

Patel, Aniruddh D; Foxton, Jessica M; Griffiths, Timothy D

2005-12-01

Musically tone-deaf individuals have psychophysical deficits in detecting pitch changes, yet their discrimination of intonation contours in speech appears to be normal. One hypothesis for this dissociation is that intonation contours use coarse pitch contrasts which exceed the pitch-change detection thresholds of tone-deaf individuals (). We test this idea by presenting intonation contours for discrimination, both in the context of the original sentences in which they occur and in a "pure" form dissociated from any phonetic context. The pure form consists of gliding-pitch analogs of the original intonation contours which exactly follow their pattern of pitch and timing. If the spared intonation perception of tone-deaf individuals is due to the coarse pitch contrasts of intonation, then such individuals should discriminate the original sentences and the gliding-pitch analogs equally well. In contrast, we find that discrimination of the gliding-pitch analogs is severely degraded. Thus it appears that the dissociation between spoken and musical pitch perception in tone-deaf individuals is due to a deficit at a higher level than simple pitch-change detection.

Perceived Discrimination and Self-Rated Health in Europe: Evidence from the European Social Survey (2010)

PubMed Central

Alvarez-Galvez, Javier; Salvador-Carulla, Luis

2013-01-01

Introduction Studies have shown that perceived discrimination has an impact on our physical and mental health. A relevant part of literature has highlighted the influence of discrimination based on race or ethnicity on mental and physical health outcomes. However, the influence of other types of discrimination on health has been understudied. This study is aimed to explore how different types of discrimination are related to our subjective state of health, and so to compare the intensity of these relationships in the European context. Methods We have performed a multilevel ordered analysis on the fifth wave of the European Social Survey (ESS 2010). This dataset has 52,458 units at individual level that are grouped in 26 European countries. In this study, the dependent variable is self-rated health (SRH) that is analyzed in relationship to ten explanatory variables of perceived discrimination: color or race, nationality, religion, language, ethnic group, age, gender, sexuality, disability and others. Results The model identifies statistically significant differences in the effect that diverse types of perceived discrimination can generate on the self-rated health of Europeans. Specifically, this study identifies three well-defined types of perceived discrimination that can be related to poor health outcomes: (1) age discrimination; (2) disability discrimination; and (3) sexuality discrimination. In this sense, the effect on self-rated health of perceived discrimination related to aging and disabilities seems to be more relevant than other types of discrimination in the European context with a longer tradition in literature (e.g. ethnic and/or race-based). Conclusion The present study shows that the relationship between perceived discrimination and health inequities in Europe are not random, but systematically distributed depending on factors such as age, sexuality and disabilities. Therefore the future orientation of EU social policies should aim to reduce the impact of these social determinants on health equity. PMID:24040216

Perceived discrimination and self-rated health in Europe: evidence from the European Social Survey (2010).

PubMed

Alvarez-Galvez, Javier; Salvador-Carulla, Luis

2013-01-01

Studies have shown that perceived discrimination has an impact on our physical and mental health. A relevant part of literature has highlighted the influence of discrimination based on race or ethnicity on mental and physical health outcomes. However, the influence of other types of discrimination on health has been understudied. This study is aimed to explore how different types of discrimination are related to our subjective state of health, and so to compare the intensity of these relationships in the European context. We have performed a multilevel ordered analysis on the fifth wave of the European Social Survey (ESS 2010). This dataset has 52,458 units at individual level that are grouped in 26 European countries. In this study, the dependent variable is self-rated health (SRH) that is analyzed in relationship to ten explanatory variables of perceived discrimination: color or race, nationality, religion, language, ethnic group, age, gender, sexuality, disability and others. The model identifies statistically significant differences in the effect that diverse types of perceived discrimination can generate on the self-rated health of Europeans. Specifically, this study identifies three well-defined types of perceived discrimination that can be related to poor health outcomes: (1) age discrimination; (2) disability discrimination; and (3) sexuality discrimination. In this sense, the effect on self-rated health of perceived discrimination related to aging and disabilities seems to be more relevant than other types of discrimination in the European context with a longer tradition in literature (e.g. ethnic and/or race-based). The present study shows that the relationship between perceived discrimination and health inequities in Europe are not random, but systematically distributed depending on factors such as age, sexuality and disabilities. Therefore the future orientation of EU social policies should aim to reduce the impact of these social determinants on health equity.

Improved pulse shape discriminator for fast neutron-gamma ray detection system

NASA Technical Reports Server (NTRS)

Lockwood, J. A.; St. Onge, R.

1969-01-01

Discriminator in nuclear particle detection system distinguishes nuclear particle type and energy among many different nuclear particles. Discriminator incorporates passive, linear circuit elements so that it will operate over a wide dynamic range.

Dynamic and predictive links between touch and vision.

PubMed

Gray, Rob; Tan, Hong Z

2002-07-01

We investigated crossmodal links between vision and touch for moving objects. In experiment 1, observers discriminated visual targets presented randomly at one of five locations on their forearm. Tactile pulses simulating motion along the forearm preceded visual targets. At short tactile-visual ISIs, discriminations were more rapid when the final tactile pulse and visual target were at the same location. At longer ISIs, discriminations were more rapid when the visual target was offset in the motion direction and were slower for offsets opposite to the motion direction. In experiment 2, speeded tactile discriminations at one of three random locations on the forearm were preceded by a visually simulated approaching object. Discriminations were more rapid when the object approached the location of the tactile stimulation and discrimination performance was dependent on the approaching object's time to contact. These results demonstrate dynamic links in the spatial mapping between vision and touch.

Conditional withholding of proboscis extension in honeybees (Apis mellifera) during discriminative punishment.

PubMed

Smith, B H; Abramson, C I; Tobin, T R

1991-12-01

Proboscis extension conditioning of honeybee workers was used to test the ability of bees to respond to appetitive and aversive stimuli while restrained in a harness that allows subjects to move their antennae and mouthparts (Kuwabara, 1957; Menzel, Erber, & Masuhr, 1974). Subjects were conditioned to discriminate between two odors, one associated with sucrose feeding and the other associated with a 10 V AC shock if they responded to the sucrose unconditioned stimulus (US) in the context of that odor. Most Ss readily learned to respond to the odor followed by sucrose feeding and not to the odor associated with sucrose stimulation plus shock. Furthermore, in the context of the odor associated with shock, significantly more subjects withheld or delayed proboscis extension on stimulation with the sucrose US than they did in the context of the odor associated with feeding. Thus, restrained honeybees can readily learn to avoid shock according to an odor context by withholding proboscis extension to a normally powerful releaser. Analysis of individual learning curves revealed that subjects differed markedly in performance on this task. Some learn the discrimination quickly, whereas others show different kinds of response patterns.

Pavlovian Extinction of the Discriminative Stimulus Effects of Nicotine and Ethanol in Rats Varies as a Function of Context

ERIC Educational Resources Information Center

Troisi, Joseph R., II

2011-01-01

Operant extinction contingencies can undermine the discriminative stimulus effects of drugs. Here, nicotine (0.4 mg/kg) and ethanol (0.8 g/kg) first functioned as either an S[superscript D] or S[superscript Delta], in a counterbalanced one-lever go/no-go (across sessions) operant drug discrimination procedure. Pavlovian extinction in the training…

Using complex networks for text classification: Discriminating informative and imaginative documents

NASA Astrophysics Data System (ADS)

de Arruda, Henrique F.; Costa, Luciano da F.; Amancio, Diego R.

2016-01-01

Statistical methods have been widely employed in recent years to grasp many language properties. The application of such techniques have allowed an improvement of several linguistic applications, such as machine translation and document classification. In the latter, many approaches have emphasised the semantical content of texts, as is the case of bag-of-word language models. These approaches have certainly yielded reasonable performance. However, some potential features such as the structural organization of texts have been used only in a few studies. In this context, we probe how features derived from textual structure analysis can be effectively employed in a classification task. More specifically, we performed a supervised classification aiming at discriminating informative from imaginative documents. Using a networked model that describes the local topological/dynamical properties of function words, we achieved an accuracy rate of up to 95%, which is much higher than similar networked approaches. A systematic analysis of feature relevance revealed that symmetry and accessibility measurements are among the most prominent network measurements. Our results suggest that these measurements could be used in related language applications, as they play a complementary role in characterising texts.

Systemic lipopolysaccharide administration impairs retrieval of context-object discrimination, but not spatial, memory: Evidence for selective disruption of specific hippocampus-dependent memory functions during acute neuroinflammation

PubMed Central

Czerniawski, Jennifer; Miyashita, Teiko; Lewandowski, Gail; Guzowski, John F.

2014-01-01

Neuroinflammation is implicated in impairments in neuronal function and cognition that arise with aging, trauma, and/or disease. Therefore, understanding the underlying basis of the effect of immune system activation on neural function could lead to therapies for treating cognitive decline. Although neuroinflammation is widely thought to preferentially impair hippocampus-dependent memory, data on the effects of cytokines on cognition are mixed. One possible explanation for these inconsistent results is that cytokines may disrupt specific neural processes underlying some forms of memory but not others. In an earlier study, we tested the effect of systemic administration of bacterial lipopolysaccharide (LPS) on retrieval of hippocampus-dependent context memory and neural circuit function in CA3 and CA1 (Czerniawski and Guzowski, 2014). Paralleling impairment in context discrimination memory, we observed changes in neural circuit function consistent with disrupted pattern separation function. In the current study we tested the hypothesis that acute neuroinflammation selectively disrupts memory retrieval in tasks requiring hippocampal pattern separation processes. Male Sprague-Dawley rats given LPS systemically prior to testing exhibited intact performance in tasks that do not require hippocampal pattern separation processes: novel object recognition and spatial memory in the water maze. By contrast, memory retrieval in a task thought to require hippocampal pattern separation, context-object discrimination, was strongly impaired in LPS-treated rats in the absence of any gross effects on exploratory activity or motivation. These data show that LPS administration does not impair memory retrieval in all hippocampus-dependent tasks, and support the hypothesis that acute neuroinflammation impairs context discrimination memory via disruption of pattern separation processes in hippocampus. PMID:25451612

Systemic lipopolysaccharide administration impairs retrieval of context-object discrimination, but not spatial, memory: Evidence for selective disruption of specific hippocampus-dependent memory functions during acute neuroinflammation.

PubMed

Czerniawski, Jennifer; Miyashita, Teiko; Lewandowski, Gail; Guzowski, John F

2015-02-01

Neuroinflammation is implicated in impairments in neuronal function and cognition that arise with aging, trauma, and/or disease. Therefore, understanding the underlying basis of the effect of immune system activation on neural function could lead to therapies for treating cognitive decline. Although neuroinflammation is widely thought to preferentially impair hippocampus-dependent memory, data on the effects of cytokines on cognition are mixed. One possible explanation for these inconsistent results is that cytokines may disrupt specific neural processes underlying some forms of memory but not others. In an earlier study, we tested the effect of systemic administration of bacterial lipopolysaccharide (LPS) on retrieval of hippocampus-dependent context memory and neural circuit function in CA3 and CA1 (Czerniawski and Guzowski, 2014). Paralleling impairment in context discrimination memory, we observed changes in neural circuit function consistent with disrupted pattern separation function. In the current study we tested the hypothesis that acute neuroinflammation selectively disrupts memory retrieval in tasks requiring hippocampal pattern separation processes. Male Sprague-Dawley rats given LPS systemically prior to testing exhibited intact performance in tasks that do not require hippocampal pattern separation processes: novel object recognition and spatial memory in the water maze. By contrast, memory retrieval in a task thought to require hippocampal pattern separation, context-object discrimination, was strongly impaired in LPS-treated rats in the absence of any gross effects on exploratory activity or motivation. These data show that LPS administration does not impair memory retrieval in all hippocampus-dependent tasks, and support the hypothesis that acute neuroinflammation impairs context discrimination memory via disruption of pattern separation processes in hippocampus. Copyright © 2014 Elsevier Inc. All rights reserved.

Further Examination of Discriminated Functional Communication

ERIC Educational Resources Information Center

Leon, Yanerys; Hausman, Nicole L.; Kahng, SungWoo; Becraft, Jessica L.

2010-01-01

One child with developmental disabilities was taught to mand for attention by saying "excuse me." Treatment effects were extended to multiple training contexts by teaching the participant to attend to naturally occurring discriminative stimuli through differential reinforcement of communication during periods of the experimenter's nonbusy…

Does perceived discrimination affect health? Longitudinal relationships between work discrimination and women's physical and emotional health.

PubMed

Pavalko, Eliza K; Mossakowski, Krysia N; Hamilton, Vanessa J

2003-03-01

This study uses longitudinal data to examine the causal relationships between perceived work discrimination and women's physical and emotional health. Using data on 1,778 employed women in the National Longitudinal Survey of Mature Women, we investigate the structural and individual characteristics that predict later perceptions of discrimination and the effects of those perceptions on subsequent health. We find that perceptions of discrimination are influenced by job attitudes, prior experiences of discrimination, and work contexts, but prior health is not related to later perceptions. However, perceptions of discrimination do impact subsequent health, and these effects remain significant after controlling for prior emotional health, physical health limitations, discrimination, and job characteristics. Overall, the results provide even stronger support for the health impact of workplace discrimination and suggest a need for further longitudinal analyses of causes and consequences of perceived discrimination.

One-laser-based generation/detection of Brillouin dynamic grating and its application to distributed discrimination of strain and temperature.

PubMed

Zou, Weiwen; He, Zuyuan; Hotate, Kazuo

2011-01-31

This paper presents a novel scheme to generate and detect Brillouin dynamic grating in a polarization-maintaining optical fiber based on one laser source. Precise measurement of Brillouin dynamic grating spectrum is achieved benefiting from that the pump, probe and readout waves are coherently originated from the same laser source. Distributed discrimination of strain and temperature is also achieved with high accuracy.

Interpersonal Valence Dimensions as Discriminators of Communication Contexts: An Empirical Assessment of Dyadic Linkages.

ERIC Educational Resources Information Center

Garrison, John P.; And Others

The capability of 14 interpersonal dimensions to predict dyadic communication contexts was investigated in this study. Friend, acquaintance, co-worker, and family contexts were examined. The interpersonal valence construct, based on a coactive or mutual-causal paradigm, encompasses traditional source-valence components (credibility, power,…

Testing the tenets of minority stress theory in workplace contexts.

PubMed

Velez, Brandon L; Moradi, Bonnie; Brewster, Melanie E

2013-10-01

The links of minority stressors (workplace discrimination, expectations of stigma, internalized heterosexism, and identity management strategies) with psychological distress and job satisfaction were examined in a sample of 326 sexual minority employees. Drawing from minority stress theory and the literature on the vocational experiences of sexual minority people, patterns of mediation and moderation were tested. Minority stressors were associated with greater distress and lower job satisfaction. A mediation model was supported in which the links of discrimination and internalized heterosexism with psychological distress were mediated by a concealment-focused identity management strategy (i.e., avoiding), and the links of discrimination, expectations of stigma, and internalized heterosexism with job satisfaction were mediated by a disclosure-focused identity management strategy (i.e., integrating). Tests of moderation indicated that for sexual minority women (but not men), the positive association of discrimination with distress was stronger at higher levels of internalized heterosexism than at lower levels. In addition, lower levels of internalized heterosexism and concealment strategies (i.e., counterfeiting and avoiding) and higher levels of a disclosure strategy (i.e., integrating) were associated with higher job satisfaction in the context of low discrimination, but this buffering effect disappeared as level of discrimination increased. The implications of these findings for minority stress research are discussed, and clinical recommendations are made.

Racial identity, social context, and race-related social cognition in African Americans during middle childhood.

PubMed

Rowley, Stephanie J; Burchinal, Margaret R; Roberts, Joanne E; Zeisel, Susan A

2008-11-01

This study examined the effect of changes in racial identity, cross-race friendships, same-race friendships, and classroom racial composition on changes in race-related social cognition from 3rd to 5th grade for 73 African American children. The goal of the study was to determine the extent to which preadolescent racial identity and social context predict expectations of racial discrimination in cross-race social interactions (social expectations). Expectations of racial discrimination were assessed using vignettes of cross-race social situations involving an African American child in a social interaction with European Americans. There were 3 major findings. First, expectations for discrimination declined slightly from 3rd to 5th grade. Second, although racial composition of children's classrooms, number of European American friends, gender, and family poverty status were largely unrelated to social expectations, having more African American friends was associated with expecting more discrimination in cross-racial interactions from 3rd to 5th grade. Third, increases in racial centrality were related to increases in discrimination expectations, and increases in public regard were associated with decreases in discrimination expectations. These data suggest that as early as 3rd grade, children are forming attitudes about their racial group that have implications for their cross-race social interactions.

Gay male attraction toward muscular men: does mating context matter?

PubMed

Varangis, Eleanna; Lanzieri, Nicholas; Hildebrandt, Tom; Feldman, Matthew

2012-03-01

The purpose of this study was to examine gay men's perceived attractiveness of male figures based on short-term and long-term partner contexts. A sample of 190 gay adult men rated the attractiveness of line-drawings depicting male figures varying systematically in muscularity and body fat percentage in both short-term and long-term dating contexts. Mixed effects modeling was used to estimate the effects of figure (muscularity and body fat), dating context (short-term vs. long-term), and individual rater characteristics on attractiveness ratings. Results indicated that figure muscularity and body-fat had significant non-linear (i.e., quadratic) relationships with attractiveness ratings, and short-term dating context was associated with more discriminating ratings of attractiveness. Interactions between individual characteristics and figure characteristics indicated that the more available the individual and lower body fat, the more discriminating they were in ratings of attractiveness. The implications for future investigations considering both object and observer characteristics of attractiveness preferences are discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Denny's: Communicating Amidst a Discrimination Case.

ERIC Educational Resources Information Center

Chin, Teresa; Naidu, Sharmila; Ringel, Jonathan; Snipes, Wayne; DeSilva, Jean; Bienvenu, Sherron Kenton

1998-01-01

Presents a case study for use in business communication classes to help students understand and learn both the context and the strategies for communication with business and management. Looks at communication strategies employed by Denny's during its crisis caused by charges of racial discrimination. Includes actual communications instrumental in…

Discrimination in a General Algebraic Setting

PubMed Central

Fine, Benjamin; Lipschutz, Seymour; Spellman, Dennis

2015-01-01

Discriminating groups were introduced by G. Baumslag, A. Myasnikov, and V. Remeslennikov as an outgrowth of their theory of algebraic geometry over groups. Algebraic geometry over groups became the main method of attack on the solution of the celebrated Tarski conjectures. In this paper we explore the notion of discrimination in a general universal algebra context. As an application we provide a different proof of a theorem of Malcev on axiomatic classes of Ω-algebras. PMID:26171421

Health for All? Sexual Orientation, Gender Identity, and the Implementation of the Right to Access to Health Care in South Africa.

PubMed

Müller, Alexandra

2016-12-01

The framework of health and human rights provides for a comprehensive theoretical and practical application of general human rights principles in health care contexts that include the well-being of patients, providers, and other individuals within health care. This is particularly important for sexual and gender minority individuals, who experience historical and contemporary systematical marginalization, exclusion, and discrimination in health care contexts. In this paper, I present two case studies from South Africa to (1) highlight the conflicts that arise when sexual and gender minority individuals seek access to a heteronormative health system; (2) discuss the international, regional, and national human rights legal framework as it pertains to sexual orientation, gender identity, and health; and (3) analyze the gap between legislative frameworks that offer protection from discrimination based on sexual orientation and gender identity and their actual implementation in health service provision. These case studies highlight the complex and intersecting discrimination and marginalization that sexual and gender minority individuals face in health care in this particular context. The issues raised in the case studies are not unique to South Africa, however; and the human rights concerns illustrated therein, particularly around the right to health, have wide resonance in other geographical and social contexts.

Health for All? Sexual Orientation, Gender Identity, and the Implementation of the Right to Access to Health Care in South Africa

PubMed Central

2016-01-01

Abstract The framework of health and human rights provides for a comprehensive theoretical and practical application of general human rights principles in health care contexts that include the well-being of patients, providers, and other individuals within health care. This is particularly important for sexual and gender minority individuals, who experience historical and contemporary systematical marginalization, exclusion, and discrimination in health care contexts. In this paper, I present two case studies from South Africa to (1) highlight the conflicts that arise when sexual and gender minority individuals seek access to a heteronormative health system; (2) discuss the international, regional, and national human rights legal framework as it pertains to sexual orientation, gender identity, and health; and (3) analyze the gap between legislative frameworks that offer protection from discrimination based on sexual orientation and gender identity and their actual implementation in health service provision. These case studies highlight the complex and intersecting discrimination and marginalization that sexual and gender minority individuals face in health care in this particular context. The issues raised in the case studies are not unique to South Africa, however; and the human rights concerns illustrated therein, particularly around the right to health, have wide resonance in other geographical and social contexts. PMID:28559686

Inactivation of the infralimbic prefrontal cortex in rats reduces the influence of inappropriate habitual responding in a response-conflict task.

PubMed

Haddon, J E; Killcross, S

2011-12-29

Previous research suggests the infralimbic cortex is important in situations when there is competition between goal-directed and habitual responding. Here we used a response conflict procedure to further explore the involvement of the infralimbic cortex in this relationship. Rats received training on two instrumental biconditional discriminations, one auditory and one visual, in two distinct contexts. One discrimination was "over-trained" relative to the other, "under-trained," discrimination in the ratio 3:1. At test, animals were presented with incongruent audiovisual stimulus compounds of the training stimuli in the under-trained context. The stimulus elements of these test compounds have previously dictated different lever press responses during training. Rats receiving control infusions into the infralimbic cortex showed a significant interference effect, producing more responses to the over-trained (habitual), but context-inappropriate, stimulus element of the incongruent compound. This interference effect was abolished by inactivation of the infralimbic cortex; animals showed a reduced tendency to produce the habitual but inappropriate response compared with animals receiving control infusions. This finding provides evidence that the infralimbic cortex is involved in attenuating the influence of goal-directed behavior, for example context-appropriate responding. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

LGBT Discrimination on Campus and Heterosexual Bystanders: Understanding Intentions to Intervene

ERIC Educational Resources Information Center

Dessel, Adrienne B.; Goodman, Kevin D.; Woodford, Michael R.

2017-01-01

Discrimination targeting lesbian, gay, bisexual, and transgender (LGBT) students on college campuses occurs. Bystander intervention is important in supporting targeted students and improving campus climate for LGBT students. Peer-familiarity context (i.e., who the bystander knows in the situation) can play a role in bystander intervention, but…

Intersensory Redundancy Hinders Face Discrimination in Preschool Children: Evidence for Visual Facilitation

ERIC Educational Resources Information Center

Bahrick, Lorraine E.; Krogh-Jespersen, Sheila; Argumosa, Melissa A.; Lopez, Hassel

2014-01-01

Although infants and children show impressive face-processing skills, little research has focused on the conditions that facilitate versus impair face perception. According to the intersensory redundancy hypothesis (IRH), face discrimination, which relies on detection of visual featural information, should be impaired in the context of…

Bacillus subtilis Protects Public Goods by Extending Kin Discrimination to Closely Related Species

PubMed Central

2017-01-01

ABSTRACT Kin discrimination systems are found in numerous communal contexts like multicellularity and are theorized to prevent exploitation of cooperative behaviors. The kin discrimination system in Bacillus subtilis differs from most other such systems because it excludes nonkin cells rather than including kin cells. Because nonkin are the target of the system, B. subtilis can potentially distinguish degrees of nonkin relatedness, not just kin versus nonkin. We examined this by testing a large strain collection of diverse Bacillus species against B. subtilis in different multicellular contexts. The effects of kin discrimination extend to nearby species, as the other subtilis clade species were treated with the same antagonism as nonkin. Species in the less-related pumilus clade started to display varied phenotypes but were mostly still discriminated against, while cereus clade members and beyond were no longer subject to kin discrimination. Seeking a reason why other species are perceived as antagonistic nonkin, we tested the ability of B. subtilis to steal communally produced surfactant from these species. We found that the species treated as nonkin were the only ones that made a surfactant that B. subtilis could utilize and that nonkin antagonism prevented such stealing when the two strains were mixed. The nonkin exclusion kin discrimination method thus allows effective protection of the cooperative behaviors prevalent in multicellularity while still permitting interactions with more distant species that are not a threat. PMID:28679746

The antecedents and consequences of racial/ethnic discrimination during adolescence: does the source of discrimination matter?

PubMed

Benner, Aprile D; Graham, Sandra

2013-08-01

In the current study, we examined the precursors and consequences of discrimination for 876 Latino, African American, and Asian American adolescents (Mage = 16.9 years, SD = 0.43). The race/ethnic characteristics of schools and neighborhoods influenced adolescents' perceptions of the race/ethnic climates of these contexts. In turn, adolescents who viewed climates more negatively were more likely to perceive discriminatory treatment by school personnel, peers, and societal institutions. Discrimination from these 3 sources exerted differential influence on developmental outcomes: Greater discrimination from school personnel was associated with poorer academic performance, greater discrimination from peers was associated with more psychological maladjustment, and greater societal discrimination was associated with heightened racial awareness. Relations were consistent across race/ethnic groups and gender. Implications for intervening to reduce racial discrimination and other social stigmas are discussed. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

Discrimination and adjustment among Chinese American adolescents: family conflict and family cohesion as vulnerability and protective factors.

PubMed

Juang, Linda P; Alvarez, Alvin A

2010-12-01

We examined racial/ethnic discrimination experiences of Chinese American adolescents to determine how discrimination is linked to poor adjustment (i.e., loneliness, anxiety, and somatization) and how the context of the family can buffer or exacerbate these links. We collected survey data from 181 Chinese American adolescents and their parents in Northern California. We conducted hierarchical regression analyses to examine main effects and 2-way interactions of perceived discrimination with family conflict and family cohesion. Discrimination was related to poorer adjustment in terms of loneliness, anxiety, and somatization, but family conflict and cohesion modified these relations. Greater family conflict exacerbated the negative effects of discrimination, and greater family cohesion buffered the negative effects of discrimination. Our findings highlight the importance of identifying family-level moderators to help adolescents and their families handle experiences of discrimination.

Discrimination concerns and expectations as explanations for gendered socialization in African American families.

PubMed

Varner, Fatima; Mandara, Jelani

2013-01-01

Discrimination concerns and parental expectations were examined as mediators of the relations between gender and parenting practices among 796 African American mothers of 11- to 14-year-olds from the Maryland Adolescent Development in Context Study. Mothers of sons had more concerns about racial discrimination impacting their adolescents' future, whereas mothers of daughters had more gender discrimination concerns. Racial discrimination concerns, but not gender discrimination concerns, were related to lower maternal academic and behavioral expectations. Maternal expectations were related to mothers' responsiveness, rule enforcement, monitoring, and parent-adolescent conflict. The relations between gender and parenting practices were partially explained through mothers' racial discrimination concerns and expectations. These findings demonstrate the importance of contextual factors on African American family processes. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

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

Dumitrescu, Eugene; Humble, Travis S.

The accurate and reliable characterization of quantum dynamical processes underlies efforts to validate quantum technologies, where discrimination between competing models of observed behaviors inform efforts to fabricate and operate qubit devices. We present a protocol for quantum channel discrimination that leverages advances in direct characterization of quantum dynamics (DCQD) codes. We demonstrate that DCQD codes enable selective process tomography to improve discrimination between entangling and correlated quantum dynamics. Numerical simulations show selective process tomography requires only a few measurement configurations to achieve a low false alarm rate and that the DCQD encoding improves the resilience of the protocol to hiddenmore » sources of noise. Lastly, our results show that selective process tomography with DCQD codes is useful for efficiently distinguishing sources of correlated crosstalk from uncorrelated noise in current and future experimental platforms.« less

Social recognition is context dependent in single male prairie voles

PubMed Central

Zheng, Da-Jiang; Foley, Lauren; Rehman, Asad; Ophir, Alexander G.

2013-01-01

Single males might benefit from knowing the identity of neighbouring males when establishing and defending boundaries. Similarly, males should discriminate between individual females if this leads to more reproductive opportunities. Contextual social cues may alter the value of learning identity. Knowing the identity of competitors that intrude into an animal’s territory may be more salient than knowing the identity of individuals on whose territory an animal is trespassing. Hence, social and environmental context could affect social recognition in many ways. Here we test social recognition of socially monogamous single male prairie voles, Microtus ochrogaster. In experiment 1 we tested recognition of male or female conspecifics and found that males discriminated between different males but not between different females. In experiment 2 we asked whether recognition of males is influenced when males are tested in their own cage (familiar), in a clean cage (neutral) or in the home cage of another male (unfamiliar). Although focal males discriminated between male conspecifics in all three contexts, individual variation in recognition was lower when males were tested in their home cage (in the presence of familiar social cues) compared to when the context lacked social cues (neutral). Experiment 1 indicates that selective pressures may have operated to enhance male territorial behaviour and indiscriminate mate selection. Experiment 2 suggests that the presence of a conspecific cue heightens social recognition and that home-field advantages might extend to social cognition. Taken together, our results indicate social recognition depends on the social and possibly territorial context. PMID:24273328

Social recognition is context dependent in single male prairie voles.

PubMed

Zheng, Da-Jiang; Foley, Lauren; Rehman, Asad; Ophir, Alexander G

2013-11-01

Single males might benefit from knowing the identity of neighbouring males when establishing and defending boundaries. Similarly, males should discriminate between individual females if this leads to more reproductive opportunities. Contextual social cues may alter the value of learning identity. Knowing the identity of competitors that intrude into an animal's territory may be more salient than knowing the identity of individuals on whose territory an animal is trespassing. Hence, social and environmental context could affect social recognition in many ways. Here we test social recognition of socially monogamous single male prairie voles, Microtus ochrogaster . In experiment 1 we tested recognition of male or female conspecifics and found that males discriminated between different males but not between different females. In experiment 2 we asked whether recognition of males is influenced when males are tested in their own cage (familiar), in a clean cage (neutral) or in the home cage of another male (unfamiliar). Although focal males discriminated between male conspecifics in all three contexts, individual variation in recognition was lower when males were tested in their home cage (in the presence of familiar social cues) compared to when the context lacked social cues (neutral). Experiment 1 indicates that selective pressures may have operated to enhance male territorial behaviour and indiscriminate mate selection. Experiment 2 suggests that the presence of a conspecific cue heightens social recognition and that home-field advantages might extend to social cognition. Taken together, our results indicate social recognition depends on the social and possibly territorial context.

Testing synaptic plasticity in dynamic mate choice decisions: N-methyl d-aspartate receptor blockade disrupts female preference

PubMed Central

Ramsey, Mary E.; Vu, Wendy; Cummings, Molly E.

2014-01-01

Social behaviours such as mate choice require context-specific responses, often with evolutionary consequences. Increasing evidence indicates that the behavioural plasticity associated with mate choice involves learning. For example, poeciliids show age-dependent changes in female preference functions and express synaptic-plasticity-associated molecular markers during mate choice. Here, we test whether social cognition is necessary for female preference behaviour by blocking the central player in synaptic plasticity, NMDAR (N-methyl d-aspartate receptor), in a poeciliid fish, Xiphophorus nigrensis. After subchronic exposure to NMDAR antagonist MK-801, female preference behaviours towards males were dramatically reduced. Overall activity levels were unaffected, but there was a directional shift from ‘social’ behaviours towards neutral activity. Multivariate gene expression patterns significantly discriminated between females with normal versus disrupted plasticity processes and correlated with preference behaviours—not general activity. Furthermore, molecular patterns support a distinction between ‘preference’ (e.g. neuroserpin, neuroligin-3, NMDAR) and ‘sociality’ (isotocin and vasotocin) gene clusters, highlighting a possible conservation between NMDAR disruption and nonapeptides in modulating behaviour. Our results suggest that mate preference may involve greater social memory processing than overall sociality, and that poeciliid preference functions integrate synaptic-plasticity-oriented ‘preference’ pathways with overall sociality to invoke dynamic, context-specific responses towards favoured males and away from unfavoured males. PMID:24807251

Spectral-temporal EEG dynamics of speech discrimination processing in infants during sleep.

PubMed

Gilley, Phillip M; Uhler, Kristin; Watson, Kaylee; Yoshinaga-Itano, Christine

2017-03-22

Oddball paradigms are frequently used to study auditory discrimination by comparing event-related potential (ERP) responses from a standard, high probability sound and to a deviant, low probability sound. Previous research has established that such paradigms, such as the mismatch response or mismatch negativity, are useful for examining auditory processes in young children and infants across various sleep and attention states. The extent to which oddball ERP responses may reflect subtle discrimination effects, such as speech discrimination, is largely unknown, especially in infants that have not yet acquired speech and language. Mismatch responses for three contrasts (non-speech, vowel, and consonant) were computed as a spectral-temporal probability function in 24 infants, and analyzed at the group level by a modified multidimensional scaling. Immediately following an onset gamma response (30-50 Hz), the emergence of a beta oscillation (12-30 Hz) was temporally coupled with a lower frequency theta oscillation (2-8 Hz). The spectral-temporal probability of this coupling effect relative to a subsequent theta modulation corresponds with discrimination difficulty for non-speech, vowel, and consonant contrast features. The theta modulation effect suggests that unexpected sounds are encoded as a probabilistic measure of surprise. These results support the notion that auditory discrimination is driven by the development of brain networks for predictive processing, and can be measured in infants during sleep. The results presented here have implications for the interpretation of discrimination as a probabilistic process, and may provide a basis for the development of single-subject and single-trial classification in a clinically useful context. An infant's brain is processing information about the environment and performing computations, even during sleep. These computations reflect subtle differences in acoustic feature processing that are necessary for language-learning. Results from this study suggest that brain responses to deviant sounds in an oddball paradigm follow a cascade of oscillatory modulations. This cascade begins with a gamma response that later emerges as a beta synchronization, which is temporally coupled with a theta modulation, and followed by a second, subsequent theta modulation. The difference in frequency and timing of the theta modulations appears to reflect a measure of surprise. These insights into the neurophysiological mechanisms of auditory discrimination provide a basis for exploring the clinically utility of the MMR TF and other auditory oddball responses.

Representation in dynamical agents.

PubMed

Ward, Ronnie; Ward, Robert

2009-04-01

This paper extends experiments by Beer [Beer, R. D. (1996). Toward the evolution of dynamical neural networks for minimally cognitive behavior. In P. Maes, M. Mataric, J. Meyer, J. Pollack, & S. Wilson (Eds.), From animals to animats 4: Proceedings of the fourth international conference on simulation of adaptive behavior (pp. 421-429). MIT Press; Beer, R. D. (2003). The dynamics of active categorical perception in an evolved model agent (with commentary and response). Adaptive Behavior, 11 (4), 209-243] with an evolved, dynamical agent to further explore the question of representation in cognitive systems. Beer's environmentally-situated visual agent was controlled by a continuous-time recurrent neural network, and evolved to perform a categorical perception task, discriminating circles from diamonds. Despite the agent's high levels of discrimination performance, Beer found no evidence of internal representation in the best-evolved agent's nervous system. Here we examine the generality of this result. We evolved an agent for shape discrimination, and performed extensive behavioral analyses to test for representation. In this case we find that agents developed to discriminate equal-width shapes exhibit what Clark [Clark, A. (1997). The dynamical challenge. Cognitive Science, 21 (4), 461-481] calls "weak-substantive representation". The agent had internal configurations that (1) were understandably related to the object in the environment, and (2) were functionally used in a task relevant way when the target was not visible to the agent.

Measuring Discrimination in Education. NBER Working Paper No. 15057

ERIC Educational Resources Information Center

Hanna, Rema; Linden. Leigh

2009-01-01

In this paper, we illustrate a methodology to measure discrimination in educational contexts. In India, we ran an exam competition through which children compete for a large financial prize. We recruited teachers to grade the exams. We then randomly assigned child "characteristics" (age, gender, and caste) to the cover sheets of the…

Questioning Discrimination through Critical Media Literacy. Findings from Seven European Countries

ERIC Educational Resources Information Center

Ranieri, Maria; Fabbro, Francesco

2016-01-01

This paper presents the main findings of an action-research study that took place in seven European countries in order to develop effective educational responses to prevent and combat discrimination. The study entailed the design of media and citizenship education activities, their implementation in the different educational contexts and the…

Sex Discrimination in Simulated Employment Contexts: A Meta-analytic Investigation.

ERIC Educational Resources Information Center

Davison, Heather K.; Burke, Michael J.

2000-01-01

The hypothesis that applicant and rater sex, job sex-type, and job-relevant information would affect discrimination against applicants was tested in simulations. Both sexes received lower ratings when applying for opposite-sex-typed jobs. Both male and female raters rated male applicants higher. Differences between male and female ratings…

Peer Contexts for Lesbian, Gay, Bisexual, and Transgender Students: Reducing Stigma, Prejudice, and Discrimination

ERIC Educational Resources Information Center

Horn, Stacey S.; Romeo, Katherine E.

2010-01-01

Peer relationships are a vital part of adolescents' lives. For lesbian, gay, bisexual, and transgender (LGBT) youth, whether these relationships are supportive and positive, or filled with stigma, prejudice, and discrimination rests, to some degree, on their heterosexual peers' attitudes and beliefs about homosexuality. For while LGBT youth may…

Collaborative Partnership: Developing Pre-Service Teachers as Inclusive Practitioners to Support Students with Disabilities

ERIC Educational Resources Information Center

Bentley-Williams, Robyn; Grima-Farrell, Christine; Long, Janette; Laws, Cath

2017-01-01

Since the introduction of anti-discrimination legislation including Australian Disability Discrimination Act, 1992 and the Disability Standards of Education, 2005, there is an increasing demand on all schools to cater effectively for more students with disabilities within an inclusive school community context. This investigation explored a…

Confusability of Consonant Phonemes in Sound Discrimination Tasks.

ERIC Educational Resources Information Center

Rudegeair, Robert E.

The findings of Marsh and Sherman's investigation, in 1970, of the speech sound discrimination ability of kindergarten subjects, are discussed in this paper. In the study a comparison was made between performance when speech sounds were presented in isolation and when speech sounds were presented in a word context, using minimal sound contrasts.…

The Reverse Discrimination Controversy. A Moral and Legal Analysis.

ERIC Educational Resources Information Center

Fullinwider, Robert K.

This book has two principal aims: to clarify the topical and controversial issue of reverse discrimination and to reach some conclusions about the rights and wrongs involved in this issue. Focusing mainly on preferential hiring, the book explicitly and extensively addresses the law and the institutional context of the issues. Examination of the…

Reactions to Discrimination, Stigmatization, Ostracism, and Other Forms of Interpersonal Rejection: A Multimotive Model

ERIC Educational Resources Information Center

Richman, Laura Smart; Leary, Mark R.

2009-01-01

This article describes a new model that provides a framework for understanding people's reactions to threats to social acceptance and belonging as they occur in the context of diverse phenomena such as rejection, discrimination, ostracism, betrayal, and stigmatization. People's immediate reactions are quite similar across different forms of…

Odor-Induced Neuronal Rhythms in the Olfactory Bulb Are Profoundly Modified in ob/ob Obese Mice

PubMed Central

Chelminski, Yan; Magnan, Christophe; Luquet, Serge H.; Everard, Amandine; Meunier, Nicolas; Gurden, Hirac; Martin, Claire

2017-01-01

Leptin, the product of the Ob(Lep) gene, is a peptide hormone that plays a major role in maintaining the balance between food intake and energy expenditure. In the brain, leptin receptors are expressed by hypothalamic cells but also in the olfactory bulb, the first central structure coding for odors, suggesting a precise function of this hormone in odor-evoked activities. Although olfaction plays a key role in feeding behavior, the ability of the olfactory bulb to integrate the energy-related signal leptin is still missing. Therefore, we studied the fate of odor-induced activity in the olfactory bulb in the genetic context of leptin deficiency using the obese ob/ob mice. By means of an odor discrimination task with concomitant local field potential recordings, we showed that ob/ob mice perform better than wild-type (WT) mice in the early stage of the task. This behavioral gain of function was associated in parallel with profound changes in neuronal oscillations in the olfactory bulb. The distribution of the peaks in the gamma frequency range was shifted toward higher frequencies in ob/ob mice compared to WT mice before learning. More notably, beta oscillatory activity, which has been shown previously to be correlated with olfactory discrimination learning, was longer and stronger in expert ob/ob mice after learning. Since oscillations in the olfactory bulb emerge from mitral to granule cell interactions, our results suggest that cellular dynamics in the olfactory bulb are deeply modified in ob/ob mice in the context of olfactory learning. PMID:28154537

Characterization of local complex structures in a recurrence plot to improve nonlinear dynamic discriminant analysis.

PubMed

Ding, Hang

2014-01-01

Structures in recurrence plots (RPs), preserving the rich information of nonlinear invariants and trajectory characteristics, have been increasingly analyzed in dynamic discrimination studies. The conventional analysis of RPs is mainly focused on quantifying the overall diagonal and vertical line structures through a method, called recurrence quantification analysis (RQA). This study extensively explores the information in RPs by quantifying local complex RP structures. To do this, an approach was developed to analyze the combination of three major RQA variables: determinism, laminarity, and recurrence rate (DLR) in a metawindow moving over a RP. It was then evaluated in two experiments discriminating (1) ideal nonlinear dynamic series emulated from the Lorenz system with different control parameters and (2) data sets of human heart rate regulations with normal sinus rhythms (n = 18) and congestive heart failure (n = 29). Finally, the DLR was compared with seven major RQA variables in terms of discriminatory power, measured by standardized mean difference (DSMD). In the two experiments, DLR resulted in the highest discriminatory power with DSMD = 2.53 and 0.98, respectively, which were 7.41 and 2.09 times the best performance from RQA. The study also revealed that the optimal RP structures for the discriminations were neither typical diagonal structures nor vertical structures. These findings indicate that local complex RP structures contain some rich information unexploited by RQA. Therefore, future research to extensively analyze complex RP structures would potentially improve the effectiveness of the RP analysis in dynamic discrimination studies.

R-Ras Contributes to LTP and Contextual Discrimination

PubMed Central

Darcy, Michael J.; Jin, Shan-Xue; Feig, Larry A.

2014-01-01

The ability to discriminate between closely related contexts is a specific form of hippocampal-dependent learning that may be impaired in certain neurodegenerative disorders such as Alzheimer's and Down Syndrome. However, signaling pathways regulating this form of learning are poorly understood. Previous studies have shown that the calcium-dependent exchange factor Ras-GRF1, an activator of Rac, Ras and R-Ras GTPases, is important for this form of learning and memory. Moreover, the ability to discriminate contexts was linked to the ability of Ras-GRF1 to promote high-frequency stimulation (HFS)-LTP via the activation of p38 Map kinase. Here, we show that R-Ras is involved in this form of learning by using virally-delivered miRNAs targeting R-Ras into the CA1 region of dorsal hippocampus and observing impaired contextual discrimination. Like the loss of GRF1, knockdown of R-Ras in the CA1 also impairs the induction of HFS-LTP and p38 Map kinase. Nevertheless, experiments indicate that this involvement of R-Ras in HFS-LTP that is required for contextual discrimination is independent of Ras-GRF1. Thus, R-Ras is a novel regulator of a form of hippocampal-dependent LTP as well as learning and memory that is affected in certain forms of neurodegenerative diseases. PMID:25043327

Pitch discrimination and melodic memory in children with autism spectrum disorders.

PubMed

Stanutz, Sandy; Wapnick, Joel; Burack, Jacob A

2014-02-01

Pitch perception is enhanced among persons with autism. We extended this finding to memory for pitch and melody among school-aged children. The purpose of this study was to investigate pitch memory in musically untrained children with autism spectrum disorders, aged 7-13 years, and to compare it to that of age- and IQ-matched typically developing children. The children were required to discriminate isolated tones in two differing contexts as well to remember melodies after a period of 1 week. The tasks were designed to employ both short- and long-term memory for music. For the pitch discrimination task, the children first had to indicate whether two isolated tones were the same or different when the second was the same or had been altered to be 25, 35, or 45 cents sharp or flat. Second, the children discriminated the tones within the context of melody. They were asked whether two melodies were the same or different when the leading tone of the second melody was the same or had been altered to be 25, 35, or 45 cents sharp or flat. Long-term memory for melody was also investigated, as the children attempted to recall four different two-bar melodies after 1 week. The children with autism spectrum disorders demonstrated elevated pitch discrimination ability in the single-tone and melodic context as well as superior long-term memory for melody. Pitch memory correlated positively with scores on measures of nonverbal fluid reasoning ability. Superior short- and long-term pitch memory was found among children with autism spectrum disorders. The results indicate an aspect to cognitive functioning that may predict both enhanced nonverbal reasoning ability and atypical language development.

Rotation and scale invariant shape context registration for remote sensing images with background variations

NASA Astrophysics Data System (ADS)

Jiang, Jie; Zhang, Shumei; Cao, Shixiang

2015-01-01

Multitemporal remote sensing images generally suffer from background variations, which significantly disrupt traditional region feature and descriptor abstracts, especially between pre and postdisasters, making registration by local features unreliable. Because shapes hold relatively stable information, a rotation and scale invariant shape context based on multiscale edge features is proposed. A multiscale morphological operator is adapted to detect edges of shapes, and an equivalent difference of Gaussian scale space is built to detect local scale invariant feature points along the detected edges. Then, a rotation invariant shape context with improved distance discrimination serves as a feature descriptor. For a distance shape context, a self-adaptive threshold (SAT) distance division coordinate system is proposed, which improves the discriminative property of the feature descriptor in mid-long pixel distances from the central point while maintaining it in shorter ones. To achieve rotation invariance, the magnitude of Fourier transform in one-dimension is applied to calculate angle shape context. Finally, the residual error is evaluated after obtaining thin-plate spline transformation between reference and sensed images. Experimental results demonstrate the robustness, efficiency, and accuracy of this automatic algorithm.

Racial/Ethnic Discrimination and Adolescents' Well-Being: The Role of Cross-Ethnic Friendships and Friends' Experiences of Discrimination.

PubMed

Benner, Aprile D; Wang, Yijie

2017-03-01

There is an extensive body of work documenting the negative socioemotional and academic consequences of perceiving racial/ethnic discrimination during adolescence, but little is known about how the larger peer context conditions such effects. Using peer network data from 252 eighth graders (85% Latino, 11% African American, 5% other race/ethnicity), the present study examined the moderating role of cross-ethnic friendships and close friends' experiences of discrimination in the link between adolescents' perceptions of discrimination and well-being. Cross-ethnic friendships and friends' experiences of discrimination generally served a protective role, buffering the negative effects of discrimination on both socioemotional well-being and school outcomes. Overall, results highlight the importance of considering racial/ethnic-related aspects of adolescents' friendships when studying interpersonal processes closely tied to race/ethnicity. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

A fundamental role for context in instrumental learning and extinction.

PubMed

Bouton, Mark E; Todd, Travis P

2014-05-01

The purpose of this article is to review recent research that has investigated the effects of context change on instrumental (operant) learning. The first part of the article discusses instrumental extinction, in which the strength of a reinforced instrumental behavior declines when reinforcers are withdrawn. The results suggest that extinction of either simple or discriminated operant behavior is relatively specific to the context in which it is learned: As in prior studies of Pavlovian extinction, ABA, ABC, and AAB renewal effects can all be observed. Further analysis supports the idea that the organism learns to refrain from making a specific response in a specific context, or in more formal terms, an inhibitory context-response association. The second part of the article then discusses research suggesting that the context also controls instrumental behavior before it is extinguished. Several experiments demonstrate that a context switch after either simple or discriminated operant training causes a decrement in the strength of the response. Over a range of conditions, the animal appears to learn a direct association between the context and the response. Under some conditions, it can also learn a hierarchical representation of context and the response-reinforcer relation. Extinction is still more context-specific than conditioning, as indicated by ABC and AAB renewal. Overall, the results establish that the context can play a significant role in both the acquisition and extinction of operant behavior. Copyright © 2014 Elsevier B.V. All rights reserved.

Dynamic Displays Enhance the Ability to Discriminate Genuine and Posed Facial Expressions of Emotion

PubMed Central

Namba, Shushi; Kabir, Russell S.; Miyatani, Makoto; Nakao, Takashi

2018-01-01

Accurately gauging the emotional experience of another person is important for navigating interpersonal interactions. This study investigated whether perceivers are capable of distinguishing between unintentionally expressed (genuine) and intentionally manipulated (posed) facial expressions attributed to four major emotions: amusement, disgust, sadness, and surprise. Sensitivity to this discrimination was explored by comparing unstaged dynamic and static facial stimuli and analyzing the results with signal detection theory. Participants indicated whether facial stimuli presented on a screen depicted a person showing a given emotion and whether that person was feeling a given emotion. The results showed that genuine displays were evaluated more as felt expressions than posed displays for all target emotions presented. In addition, sensitivity to the perception of emotional experience, or discriminability, was enhanced in dynamic facial displays, but was less pronounced in the case of static displays. This finding indicates that dynamic information in facial displays contributes to the ability to accurately infer the emotional experiences of another person. PMID:29896135

Sex Differences in the Generalization of Fear as a Function of Retention Intervals

ERIC Educational Resources Information Center

Lynch, Joseph, III; Cullen, Patrick K.; Jasnow, Aaron M.; Riccio, David C.

2013-01-01

In previous studies using male rodents, context change disrupted a fear response at a short, but not a long, retention interval. Here, we examined the effects of context changes on fear responses as a function of time in male and female rats. Males displayed context discrimination at all intervals, whereas females exhibited generalization by 5 d.…

Religious identification and politicization in the face of discrimination: support for political Islam and political action among the Turkish and Moroccan second generation in Europe.

PubMed

Fleischmann, Fenella; Phalet, Karen; Klein, Olivier

2011-12-01

Taking an approach from religion as a social identity and using large-scale comparative surveys in five European cities, we investigate when and how perceived discrimination is associated with religious identification and politicization among the second generation of Turkish and Moroccan Muslims. We distinguish support for political Islam from political action as distinct forms of politicization. In addition, we test the mediating role of religious identification in processes of politicization. Study 1 estimates multi-group structural equation models of support for political Islam in Belgium, the Netherlands, and Sweden. In line with a social identity model of politicization and across nine inter-group contexts, Muslims who perceived more discrimination identified (even) more strongly as Muslims; and high Muslim identifiers were most ready to support political Islam. In support of a competing social stigma hypothesis, however, negative direct and total effects of perceived discrimination suggest predominant depoliticization. Using separate sub-samples across four inter-group contexts in Belgium, Study 2 adds political action tendencies as a distinct form of politicization. Whereas religious identification positively predicts both forms of politicization, perceived discrimination has differential effects: Muslims who perceived more discrimination were more weary of supporting political Islam, yet more ready to engage in political action to defend Islamic values. Taken together, the studies reveal that some Muslim citizens will politicize and others will depoliticize in the face of discrimination as a function of their religious identification and of prevailing forms of politicization. ©2011 The British Psychological Society.

The weight of racism: Vigilance and racial inequalities in weight-related measures

PubMed Central

Hicken, Margaret T.; Lee, Hedwig; Hing, Anna K.

2017-01-01

In the United States, racial/ethnic inequalities in obesity are well-documented, particularly among women. Using the Chicago Community Adult Health Study, a probability-based sample in 2001–2003 (N=3,105), we examined the roles of discrimination and vigilance in racial inequalities in two weight-related measures, body mass index (BMI) and waist circumference (WC), viewed through a cultural racism lens. Cultural racism creates a social environment in which Black Americans bear the stigma burden of their racial group while White Americans are allowed to view themselves as individuals. We propose that in this context, interpersonal discrimination holds a different meaning for Blacks and Whites, while vigilance captures the coping style for Blacks who carry the stigma burden of the racial group. By placing discrimination and vigilance within the context of cultural racism, we operationalize existing survey measures and utilize statistical models to clarify the ambiguous associations between discrimination and weight-related inequalities in the extant literature. Multivariate models were estimated for BMI and WC separately and were stratified by gender. Black women had higher mean BMI and WC than any other group, as well as highest levels of vigilance. White women did not show an association between vigilance and WC but did show a strong positive association between discrimination and WC. Conversely, Black women displayed an association between vigilance and WC, but not between discrimination and WC. These results demonstrate that vigilance and discrimination may hold different meanings for obesity by ethnoracial group that are concealed when all women are examined together and viewed without considering a cultural racism lens. PMID:28372829

"I don't care about you as a person": Sexual minority women objectified.

PubMed

Tebbe, Elliot A; Moradi, Bonnie; Connelly, Kathleen E; Lenzen, Alexandra L; Flores, Mirella

2018-01-01

This study investigates sexual minority women's experiences of objectification in the United States. Data from 5 focus groups with 33 sexual minority women were analyzed using thematic analysis (Braun & Clarke, 2006, 2012). Results revealed 6 themes and 34 subthemes grouped into "manifestations of objectification: general and explicit intersections," "immediate context of relational and situational characteristics," and "broader context of oppression and privilege along gender and sexualities." First, sexual minority women's experiences of objectification included both general manifestations described in prior research with heterosexual women and manifestations of objectification that reflected intersections of systems of inequality based on sexual orientation, gender identity, race, ethnicity, culture, and age. Second, participants identified novel relational and situational characteristics of objectification. Finally, participants included experiences of stereotyping, discrimination, and dehumanization in their conceptualizations of objectification, connecting their experiences of objectification with broader dynamics of power related to gender and sexuality. Centralizing sexual minority women's experiences, this study produced a fuller understanding of objectification experiences in general and of sexual minority women's experiences in particular. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

A numerical study of sensory-guided multiple views for improved object identification

NASA Astrophysics Data System (ADS)

Blakeslee, B. A.; Zelnio, E. G.; Koditschek, D. E.

2014-06-01

We explore the potential on-line adjustment of sensory controls for improved object identification and discrimination in the context of a simulated high resolution camera system carried onboard a maneuverable robotic platform that can actively choose its observational position and pose. Our early numerical studies suggest the significant efficacy and enhanced performance achieved by even very simple feedback-driven iteration of the view in contrast to identification from a fixed pose, uninformed by any active adaptation. Specifically, we contrast the discriminative performance of the same conventional classification system when informed by: a random glance at a vehicle; two random glances at a vehicle; or a random glance followed by a guided second look. After each glance, edge detection algorithms isolate the most salient features of the image and template matching is performed through the use of the Hausdor↵ distance, comparing the simulated sensed images with reference images of the vehicles. We present initial simulation statistics that overwhelmingly favor the third scenario. We conclude with a sketch of our near-future steps in this study that will entail: the incorporation of more sophisticated image processing and template matching algorithms; more complex discrimination tasks such as distinguishing between two similar vehicles or vehicles in motion; more realistic models of the observers mobility including platform dynamics and eventually environmental constraints; and expanding the sensing task beyond the identification of a specified object selected from a pre-defined library of alternatives.

Effect of musical training on static and dynamic measures of spectral-pattern discrimination.

PubMed

Sheft, Stanley; Smayda, Kirsten; Shafiro, Valeriy; Maddox, W Todd; Chandrasekaran, Bharath

2013-06-01

Both behavioral and physiological studies have demonstrated enhanced processing of speech in challenging listening environments attributable to musical training. The relationship, however, of this benefit to auditory abilities as assessed by psychoacoustic measures remains unclear. Using tasks previously shown to relate to speech-in-noise perception, the present study evaluated discrimination ability for static and dynamic spectral patterns by 49 listeners grouped as either musicians or nonmusicians. The two static conditions measured the ability to detect a change in the phase of a logarithmic sinusoidal spectral ripple of wideband noise with ripple densities of 1.5 and 3.0 cycles per octave chosen to emphasize either timbre or pitch distinctions, respectively. The dynamic conditions assessed temporal-pattern discrimination of 1-kHz pure tones frequency modulated by different lowpass noise samples with thresholds estimated in terms of either stimulus duration or signal-to-noise ratio. Musicians performed significantly better than nonmusicians on all four tasks. Discriminant analysis showed that group membership was correctly predicted for 88% of the listeners with the structure coefficient of each measure greater than 0.51. Results suggest that enhanced processing of static and dynamic spectral patterns defined by low-rate modulation may contribute to the relationship between musical training and speech-in-noise perception. [Supported by NIH.].

Discrimination between cocaine-associated context and cue in a modified conditioned place preference paradigm: role of the nNOS gene in cue conditioning.

PubMed

Itzhak, Yossef; Roger-Sánchez, Concepción; Kelley, Jonathan B; Anderson, Karen L

2010-03-01

The conditioned place preference (CPP) paradigm entails appetitive learning and is utilized to investigate the motivational effects of drug and natural reward in rodents. However, a typical CPP design does not allow dissociation between cue- and context-dependent appetitive learning. In humans, context and cues that had been associated with drug reward can elicit conditioned response and drug craving. Therefore, we investigated (a) methods by which to discriminate between cue- and context-dependent appetitive learning, and (b) the role of the neuronal nitric oxide synthase (nNOS) gene in appetitive learning. Wild-type (WT) and nNOS knockout (KO) mice were trained by cocaine (20 mg/kg) in a discrete context paired with a light cue (a compound context-cue stimulus). In test 1, approach behaviour to either the training context or to the cue in a novel context was determined. WT mice showed robust preference for both cocaine-associated context and cue. nNOS KO mice acquired approach behaviour for the cocaine-associated context but not cue. This finding suggests that the nNOS gene is required for cue-dependent appetitive learning. On the following day (test 2), mice were tested for approach behaviour to the compound context-cue stimulus. Context but not cue exposure in test 1 reduced approach behaviour to the compound context-cue stimulus in test 2, suggesting that repeated context but not cue exposures diminished the conditioned response. Hence, this modified CPP paradigm is useful for the investigation of approach behaviour for both drug-associated context and cue, and allows further investigation of mechanisms underlying cue- and context-dependent appetitive learning.

Cortical and thalamic contributions to response dynamics across layers of the primary somatosensory cortex during tactile discrimination

PubMed Central

Pais-Vieira, Miguel; Kunicki, Carolina; Tseng, Po-He; Martin, Joel; Lebedev, Mikhail

2015-01-01

Tactile information processing in the rodent primary somatosensory cortex (S1) is layer specific and involves modulations from both thalamocortical and cortico-cortical loops. However, the extent to which these loops influence the dynamics of the primary somatosensory cortex while animals execute tactile discrimination remains largely unknown. Here, we describe neural dynamics of S1 layers across the multiple epochs defining a tactile discrimination task. We observed that neuronal ensembles within different layers of the S1 cortex exhibited significantly distinct neurophysiological properties, which constantly changed across the behavioral states that defined a tactile discrimination. Neural dynamics present in supragranular and granular layers generally matched the patterns observed in the ventral posterior medial nucleus of the thalamus (VPM), whereas the neural dynamics recorded from infragranular layers generally matched the patterns from the posterior nucleus of the thalamus (POM). Selective inactivation of contralateral S1 specifically switched infragranular neural dynamics from POM-like to those resembling VPM neurons. Meanwhile, ipsilateral M1 inactivation profoundly modulated the firing suppression observed in infragranular layers. This latter effect was counterbalanced by contralateral S1 block. Tactile stimulus encoding was layer specific and selectively affected by M1 or contralateral S1 inactivation. Lastly, causal information transfer occurred between all neurons in all S1 layers but was maximal from infragranular to the granular layer. These results suggest that tactile information processing in the S1 of awake behaving rodents is layer specific and state dependent and that its dynamics depend on the asynchronous convergence of modulations originating from ipsilateral M1 and contralateral S1. PMID:26180115

Discrimination of Complex Human Behavior by Pigeons (Columba livia) and Humans

PubMed Central

Qadri, Muhammad A. J.; Sayde, Justin M.; Cook, Robert G.

2014-01-01

The cognitive and neural mechanisms for recognizing and categorizing behavior are not well understood in non-human animals. In the current experiments, pigeons and humans learned to categorize two non-repeating, complex human behaviors (“martial arts” vs. “Indian dance”). Using multiple video exemplars of a digital human model, pigeons discriminated these behaviors in a go/no-go task and humans in a choice task. Experiment 1 found that pigeons already experienced with discriminating the locomotive actions of digital animals acquired the discrimination more rapidly when action information was available than when only pose information was available. Experiments 2 and 3 found this same dynamic superiority effect with naïve pigeons and human participants. Both species used the same combination of immediately available static pose information and more slowly perceived dynamic action cues to discriminate the behavioral categories. Theories based on generalized visual mechanisms, as opposed to embodied, species-specific action networks, offer a parsimonious account of how these different animals recognize behavior across and within species. PMID:25379777

Health state after treatment: a reason for discrimination?

PubMed

Abellan-Perpiñan, J M; Pinto-Prades, J L

1999-12-01

In this paper the issue of discrimination between patients based on the health improvement that each can achieve is addressed. Previous research in this area by Nord has shown that, in this context, society's preferences may be quite opposite to the principle of health maximization present in cost utility analysis. Using a different experimental design from that used by Nord, some results are achieved which suggest that social preferences may be somewhere in between two opposite extremes, which are that discrimination based on the degree of health improvement is never acceptable and that discrimination based on the degree of health improvement is always acceptable. Copyright 1999 John Wiley & Sons, Ltd.

Confronting as autonomy promotion: Speaking up against discrimination and psychological well-being in racial minorities.

PubMed

Sanchez, Diana T; Himmelstein, Mary S; Young, Danielle M; Albuja, Analia F; Garcia, Julie A

2016-09-01

Few studies have considered confrontation in the context of coping with discriminatory experiences. These studies test for the first time whether confronting racial discrimination is associated with greater psychological well-being and physical health through the promotion of autonomy. In two separate samples of racial minorities who had experienced racial discrimination, confrontation was associated with greater psychological well-being, and this relationship was mediated by autonomy promotion. These findings did not extend to physical health symptoms. These studies provide preliminary evidence that confrontation may aid in the process of regaining autonomy after experiencing discrimination and therefore promote well-being. © The Author(s) 2015.

Toward Equal Educational Opportunity: Affirmative Admissions Programs at Law and Medical Schools.

ERIC Educational Resources Information Center

Riedman, Larry, Ed.

Affirmative admissions programs at law and medical schools are examined in the context of the national commitments to equal opportunity and to the eradication of the remaining effects of discrimination. A discussion is presented of the history of past discrimination in education, particularly higher education, and some of its continuing effects,…

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

Tully, Stephen

Electricity access is already well established within the framework of human rights, either as an implicit attribute of a pre-existing right (such as non-discrimination or sustainable development) or explicitly in the context of eliminating discrimination against women. There is also broad acknowledgement by states of the desirability of eliminating energy poverty - for all, but particularly for the rural poor, and women. (author)

Differences and discriminatory power of water polo game-related statistics in men in international championships and their relationship with the phase of the competition.

PubMed

Escalante, Yolanda; Saavedra, Jose M; Tella, Victor; Mansilla, Mirella; García-Hermoso, Antonio; Domínguez, Ana M

2013-04-01

The aims of this study were (a) to compare water polo game-related statistics by context (winning and losing teams) and phase (preliminary, classification, and semifinal/bronze medal/gold medal), and (b) identify characteristics that discriminate performances for each phase. The game-related statistics of the 230 men's matches played in World Championships (2007, 2009, and 2011) and European Championships (2008 and 2010) were analyzed. Differences between contexts (winning or losing teams) in each phase (preliminary, classification, and semifinal/bronze medal/gold medal) were determined using the chi-squared statistic, also calculating the effect sizes of the differences. A discriminant analysis was then performed after the sample-splitting method according to context (winning and losing teams) in each of the 3 phases. It was found that the game-related statistics differentiate the winning from the losing teams in each phase of an international championship. The differentiating variables are both offensive and defensive, including action shots, sprints, goalkeeper-blocked shots, and goalkeeper-blocked action shots. However, the number of discriminatory variables decreases as the phase becomes more demanding and the teams become more equally matched. The discriminant analysis showed the game-related statistics to discriminate performance in all phases (preliminary, classificatory, and semifinal/bronze medal/gold medal phase) with high percentages (91, 90, and 73%, respectively). Again, the model selected both defensive and offensive variables.

No experience required: Violent crime and anticipated, vicarious, and experienced racial discrimination.

PubMed

Herda, Daniel; McCarthy, Bill

2018-02-01

There is a growing body of evidence linking racial discrimination and juvenile crime, and a number of theories explain this relationship. In this study, we draw on one popular approach, Agnew's general strain theory, and extend prior research by moving from a focus on experienced discrimination to consider two other forms, anticipated and vicarious discrimination. Using data on black, white, and Hispanic youth, from the Project on Human Development in Chicago Neighborhoods (PHDCN), we find that experienced, anticipated, and to a lesser extent, vicarious discrimination, significantly predict violent crime independent of a set of neighborhood, parental, and individual level controls, including prior violent offending. Additional analyses on the specific contexts of discrimination reveal that violence is associated with the anticipation of police discrimination. The effects tend to be larger for African American than Hispanic youth, but the differences are not statistically significant. These findings support the thesis that, like other strains, discrimination may not have to be experienced directly to influence offending. Copyright © 2017. Published by Elsevier Inc.

Longitudinal relationships between antiretroviral treatment adherence and discrimination due to HIV-serostatus, race, and sexual orientation among African-American men with HIV.

PubMed

Bogart, Laura M; Wagner, Glenn J; Galvan, Frank H; Klein, David J

2010-10-01

African-Americans show worse HIV disease outcomes compared to Whites. Health disparities may be aggravated by discrimination, which is associated with worse health and maladaptive health behaviors. We examined longitudinal effects of discrimination on antiretroviral treatment adherence among 152 HIV-positive Black men who have sex with men. We measured adherence and discrimination due to HIV-serostatus, race/ethnicity, and sexual orientation at baseline and monthly for 6 months. Hierarchical repeated-measures models tested longitudinal effects of each discrimination type on adherence. Over 6 months, participants took 60% of prescribed medications on average; substantial percentages experienced discrimination (HIV-serostatus, 38%; race/ethnicity, 40%; and sexual orientation, 33%). Greater discrimination due to all three characteristics was significantly bivariately associated with lower adherence (all p's < 0.05). In the multivariate model, only racial discrimination was significant (p < 0.05). Efforts to improve HIV treatment adherence should consider the context of multiple stigmas, especially racism.

Perceived Discrimination and Psychological Well-Being: The Mediating and Moderating Role of Sense of Control

ERIC Educational Resources Information Center

Jang, Yuri; Chiriboga, David A.; Small, Brent J.

2008-01-01

Being discriminated against is an unpleasant and stressful experience, and its connection to reduced psychological well-being is well-documented. The present study hypothesized that a sense of control would serve as both mediator and moderator in the dynamics of perceived discrimination and psychological well-being. In addition, variations by age,…

Intra-trophic isotopic discrimination of 15N/14N for amino acids in autotrophs: Implications for nitrogen dynamics in ecological studies

USDA-ARS?s Scientific Manuscript database

Metabolic reactions within heterotrophs cause discrimination in their stable nitrogen isotopic composition of amino acids (d15NAA) compared to their diets. Ecologists have exploited this measurable inter-trophic discrimination in the d15NAA value to estimate the trophic positions of heterotrophic an...

Temporal Context, Preference, and Resistance to Change

ERIC Educational Resources Information Center

Podlesnik, Christopher A.; Jimenez-Gomez, Corina; Thrailkill, Eric A.; Shahan, Timothy A.

2011-01-01

According to behavioral momentum theory, preference and relative resistance to change in concurrent chains schedules are correlated and reflect the relative conditioned value of discriminative stimuli. In the present study, we explore the generality of this relation by manipulating the temporal context within a concurrent-chains procedure through…

Pricing and Marketing Online Information Services.

ERIC Educational Resources Information Center

Webber, Sheila Anne Elizabeth

1998-01-01

Discusses the pricing of online information in the broader context of marketing. Highlights include changes in the marketing context and issues of value relating to price; other reviews of online pricing; trends affecting price, including public sector involvement and the Internet; promotional pricing; price discrimination; and price aggregation…

A Dangerous Context Changes the Way That Rats Learn about and Discriminate between Innocuous Events in Sensory Preconditioning

ERIC Educational Resources Information Center

Holmes, Nathan M.; Westbrook, R. Frederick

2017-01-01

Four experiments used a sensory preconditioning protocol to examine how a dangerous context influences learning about innocuous events. In Experiments 1, 2, and 3, rats were exposed to presentations of a tone followed immediately or 20-sec later by presentations of a light. These tone-light pairings occurred in a context that was either familiar…

Reflections on discrimination and health in India.

PubMed

Srivatsan, R

2015-01-01

This is a speculative paper on the structure of caste-based discrimination in India. It sketches the field by a) proposing four empirical and historical examples of discrimination in different medical situations; b) suggesting an analytical framework composed of domain, register, temporality and intensity of discrimination; c) proposing that in the Indian historical context, discrimination masks itself, hiding its character behind the veneer of secular ideas; d) arguing that discrimination is not some unfortunate residue of backwardness in modern society that will go away, but is the force of social hierarchy transforming itself into a fully modern capitalist culture. The paper then arrives at the understanding that discrimination is pandemic across India. The conclusion suggests that in India today, we need proposals, hypotheses and arguments that help us establish the ethical framework for meaningful empirical research that sociological studies of medical ethics and the epidemiology of discrimination can pursue. Its method is that of logical and speculative argument based on experience, with examples of different forms of discrimination to clarify the point being made. No specific research was undertaken for this purpose since the paper is not empirically based.

Discrimination of time-dependent inflow properties with a cooperative dynamical system.

PubMed

Ueno, Hiroshi; Tsuruyama, Tatsuaki; Nowakowski, Bogdan; Górecki, Jerzy; Yoshikawa, Kenichi

2015-10-01

Many physical, chemical, and biological systems exhibit a cooperative or sigmoidal response with respect to the input. In biochemistry, such behavior is called an allosteric effect. Here, we demonstrate that a system with such properties can be used to discriminate the amplitude or frequency of an external periodic perturbation. Numerical simulations performed for a model sigmoidal kinetics illustrate that there exists a narrow range of frequencies and amplitudes within which the system evolves toward significantly different states. Therefore, observation of system evolution should provide information about the characteristics of the perturbation. The discrimination properties for periodic perturbation are generic. They can be observed in various dynamical systems and for different types of periodic perturbation.

Detection of internal cracks in rubber composite structures using an impact acoustic modality

NASA Astrophysics Data System (ADS)

Shen, Q.; Kurfess, T. R.; Omar, M.; Gramling, F.

2014-01-01

The objective of this study is to investigate the use of impact acoustic signals to non-intrusively inspect rubber composite structures for the presence of internal cracks, such as those found in an automobile tyre. Theoretical contact dynamic models for both integral and defective rubber structures are developed based on Hertz's impact model, further modified for rubber composite materials. The model generates the prediction of major impact dynamic quantities, namely the maximum impact force, impact duration and contact deformation; such parameters are also theoretically proven to be correlated with the presence of internal cracks. The tyre structures are simplified into cubic rubber blocks, to mitigate complexity for analytical modelling. Both impact force and impact sound signals are measured experimentally, and extraction of useful features from both signals for defect identification is achieved. The impact force produces two direct measurements of theoretical impact dynamic quantities. A good correlation between these experimental discriminators and the theoretical dynamic quantities provide validation for the contact dynamics models. Defect discriminators extracted from the impact sound are dependent on both time- and frequency-domain analyses. All the discriminators are closely connected with the theoretical dynamic quantities and experimentally verified as good indicators of internal cracks in rubber composite structures.

Legal update: living with the Genetic Information Nondiscrimination Act

PubMed Central

Erwin, Cheryl

2013-01-01

The Genetic Information Nondiscrimination Act of 2008 promises to make genetic discrimination illegal in the contexts of employment and health insurance. The promises of the law may be difficult to fully deliver. This article will examine some of the more important provisions that offer protection against genetic discrimination and the major shortcomings of the legislation. It concludes that the Genetic Information Nondiscrimination Act is an important piece of civil rights legislation, but it is not fully protective of individuals who are worried about genetic discrimination in employment or insurance. PMID:19092438

Discrimination and victimization: parade for lesbian, gay, bisexual, and transgender (LGBT) pride, in Chile.

PubMed

Barrientos, Jaime; Silva, Jimena; Catalan, Susan; Gomez, Fabiola; Longueira, Jimena

2010-01-01

This article describes the population participating in the LGBT Pride Parade in Santiago, Chile, from discrimination and victimization standpoints. The sample consisted of 488 subjects older than 18 years (M = 25.1), who were interviewed during the 2007 event. For this purpose, a questionnaire from the Latin American Centre of Sexuality and Human Rights (CLAM) was adapted and administered. Approximately 35% of respondents reported having experimented school, religious, or neighborhood discrimination. The more discriminated are transgender people. Approximately three fourths of respondents reported experiencing ridicule and almost 60% reported experiencing insults or threats. Transgender were significantly more likely than gay men, lesbians, and bisexuals to experience discrimination or victimization events. Finally, the parade acquired an important social and political character in the context of a clearly homophobic society.

How to combat the negative impact of discrimination in a collectivist context? The safeguarding function of peer-oriented hope.

PubMed

Datu, Jesus Alfonso D; Jose Mateo, Nino

2017-03-01

The objective of the study was to assess the moderating role of locus-of-hope on the relations between everyday discrimination and well-being outcomes in a collectivist setting. There were 444 Filipino undergraduate students who participated in the research. Findings showed that discrimination was negatively linked to subjective well-being and flourishing while loci-of-hope (internal, external-spiritual, external-family, and external-peers) were positively associated with well-being indices. Further, external-peer locus-of-hope moderated the relations between everyday discrimination and well-being outcomes such that for those who had higher external-peer locus-of-hope, everyday discrimination may still be linked to greater well-being. The theoretical and practical implications are elucidated.

African American Students' Perceptions of Differential Treatment in Learning Environments: Examining the Moderating Role of Peer Support, Connection to Heritage, and Discrimination Efficacy

ERIC Educational Resources Information Center

Brittian, Aerika S.; Gray, DeLeon L.

2014-01-01

This study examined the relationship between African American students' perceptions of differential treatment by teachers and educational outcomes, and the factors that promote these outcomes in the context of perceived discrimination, focusing on the protective value of youth's cultural heritage, as well as individual characteristics. The…

Engaging with Issues of Cultural Diversity and Discrimination through Critical Emotional Reflexivity in Online Learning

ERIC Educational Resources Information Center

Zembylas, Michalinos

2008-01-01

The purposes of this article are to describe the adult learners' emotional experiences as a result of engaging with issues of cultural diversity and discrimination, and to interrogate the ways in which critical emotional reflexivity emerges in the online format. The analysis is done in the context of an online course on diversity, inequality, and…

Adult Discrimination against Children: The Case of Abstinence-Only Education in Twenty-First-Century USA

ERIC Educational Resources Information Center

Greslé-Favier, Claire

2013-01-01

This paper analyses abstinence-only education programmes and discourses within the frame of theories of adult discrimination against children. To begin with, a definition of abstinence-only programmes and of the political context in which they were created will be provided. These programmes will then be analysed through the lens of children's…

Understanding the contributions of visual stimuli to contextual fear conditioning: A proof-of-concept study using LCD screens.

PubMed

Murawski, Nathen J; Asok, Arun

2017-01-10

The precise contribution of visual information to contextual fear learning and discrimination has remained elusive. To better understand this contribution, we coupled the context pre-exposure facilitation effect (CPFE) fear conditioning paradigm with presentations of distinct visual scenes displayed on 4 LCD screens surrounding a conditioning chamber. Adult male Long-Evans rats received non-reinforced context pre-exposure on Day 1, an immediate 1.5mA foot shock on Day 2, and a non-reinforced context test on Day 3. Rats were pre-exposed to either digital Context (dCtx) A, dCtx B, a distinct Ctx C, or no context on Day 1. Digital context A and B were identical except for the visual image displayed on the LCD screens. Immediate shock and retention testing occurred in dCtx A. Rats pre-exposed dCtx A showed the CPFE with significantly higher levels of freezing compared to controls. Rats pre-exposed to Context B failed to show the CPFE, with freezing that did not highly differ from controls. These results suggest that visual information contributes to contextual fear learning and that visual components of the context can be manipulated via LCD screens. Our approach offers a simple modification to contextual fear conditioning paradigms whereby the visual features of a context can be manipulated to better understand the factors that contribute to contextual fear discrimination and generalization. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The weight of racism: Vigilance and racial inequalities in weight-related measures.

PubMed

Hicken, Margaret T; Lee, Hedwig; Hing, Anna K

2018-02-01

In the United States, racial/ethnic inequalities in obesity are well-documented, particularly among women. Using the Chicago Community Adult Health Study, a probability-based sample in 2001-2003 (N = 3105), we examined the roles of discrimination and vigilance in racial inequalities in two weight-related measures, body mass index (BMI) and waist circumference (WC), viewed through a cultural racism lens. Cultural racism creates a social environment in which Black Americans bear the stigma burden of their racial group while White Americans are allowed to view themselves as individuals. We propose that in this context, interpersonal discrimination holds a different meaning for Blacks and Whites, while vigilance captures the coping style for Blacks who carry the stigma burden of the racial group. By placing discrimination and vigilance within the context of cultural racism, we operationalize existing survey measures and utilize statistical models to clarify the ambiguous associations between discrimination and weight-related inequalities in the extant literature. Multivariate models were estimated for BMI and WC separately and were stratified by gender. Black women had higher mean BMI and WC than any other group, as well as highest levels of vigilance. White women did not show an association between vigilance and WC but did show a strong positive association between discrimination and WC. Conversely, Black women displayed an association between vigilance and WC, but not between discrimination and WC. These results demonstrate that vigilance and discrimination may hold different meanings for obesity by ethnoracial group that are concealed when all women are examined together and viewed without considering a cultural racism lens. Copyright © 2017 Elsevier Ltd. All rights reserved.

In Situ Probe Science at Saturn

NASA Technical Reports Server (NTRS)

Atkinson, D.H.; Lunine, J.I.; Simon-Miller, A. A.; Atreya, S. K.; Brinckerhoff, W.; Colaprete, A.; Coustenis, A.; Fletcher, L. N.; Guillot, T.; Lebreton, J.-P.;

Does attention play a role in dynamic receptive field adaptation to changing acoustic salience in A1?

PubMed

Fritz, Jonathan B; Elhilali, Mounya; David, Stephen V; Shamma, Shihab A

2007-07-01

Acoustic filter properties of A1 neurons can dynamically adapt to stimulus statistics, classical conditioning, instrumental learning and the changing auditory attentional focus. We have recently developed an experimental paradigm that allows us to view cortical receptive field plasticity on-line as the animal meets different behavioral challenges by attending to salient acoustic cues and changing its cortical filters to enhance performance. We propose that attention is the key trigger that initiates a cascade of events leading to the dynamic receptive field changes that we observe. In our paradigm, ferrets were initially trained, using conditioned avoidance training techniques, to discriminate between background noise stimuli (temporally orthogonal ripple combinations) and foreground tonal target stimuli. They learned to generalize the task for a wide variety of distinct background and foreground target stimuli. We recorded cortical activity in the awake behaving animal and computed on-line spectrotemporal receptive fields (STRFs) of single neurons in A1. We observed clear, predictable task-related changes in STRF shape while the animal performed spectral tasks (including single tone and multi-tone detection, and two-tone discrimination) with different tonal targets. A different set of task-related changes occurred when the animal performed temporal tasks (including gap detection and click-rate discrimination). Distinctive cortical STRF changes may constitute a "task-specific signature". These spectral and temporal changes in cortical filters occur quite rapidly, within 2min of task onset, and fade just as quickly after task completion, or in some cases, persisted for hours. The same cell could multiplex by differentially changing its receptive field in different task conditions. On-line dynamic task-related changes, as well as persistent plastic changes, were observed at a single-unit, multi-unit and population level. Auditory attention is likely to be pivotal in mediating these task-related changes since the magnitude of STRF changes correlated with behavioral performance on tasks with novel targets. Overall, these results suggest the presence of an attention-triggered plasticity algorithm in A1 that can swiftly change STRF shape by transforming receptive fields to enhance figure/ground separation, by using a contrast matched filter to filter out the background, while simultaneously enhancing the salient acoustic target in the foreground. These results favor the view of a nimble, dynamic, attentive and adaptive brain that can quickly reshape its sensory filter properties and sensori-motor links on a moment-to-moment basis, depending upon the current challenges the animal faces. In this review, we summarize our results in the context of a broader survey of the field of auditory attention, and then consider neuronal networks that could give rise to this phenomenon of attention-driven receptive field plasticity in A1.

Radiotherapy volume delineation using dynamic [18F]-FDG PET/CT imaging in patients with oropharyngeal cancer: a pilot study.

PubMed

Silvoniemi, Antti; Din, Mueez U; Suilamo, Sami; Shepherd, Tony; Minn, Heikki

2016-11-01

Delineation of gross tumour volume in 3D is a critical step in the radiotherapy (RT) treatment planning for oropharyngeal cancer (OPC). Static [ 18 F]-FDG PET/CT imaging has been suggested as a method to improve the reproducibility of tumour delineation, but it suffers from low specificity. We undertook this pilot study in which dynamic features in time-activity curves (TACs) of [ 18 F]-FDG PET/CT images were applied to help the discrimination of tumour from inflammation and adjacent normal tissue. Five patients with OPC underwent dynamic [ 18 F]-FDG PET/CT imaging in treatment position. Voxel-by-voxel analysis was performed to evaluate seven dynamic features developed with the knowledge of differences in glucose metabolism in different tissue types and visual inspection of TACs. The Gaussian mixture model and K-means algorithms were used to evaluate the performance of the dynamic features in discriminating tumour voxels compared to the performance of standardized uptake values obtained from static imaging. Some dynamic features showed a trend towards discrimination of different metabolic areas but lack of consistency means that clinical application is not recommended based on these results alone. Impact of inflammatory tissue remains a problem for volume delineation in RT of OPC, but a simple dynamic imaging protocol proved practicable and enabled simple data analysis techniques that show promise for complementing the information in static uptake values.

R-Ras contributes to LTP and contextual discrimination.

PubMed

Darcy, M J; Jin, S-X; Feig, L A

2014-09-26

The ability to discriminate between closely related contexts is a specific form of hippocampal-dependent learning that may be impaired in certain neurodegenerative disorders such as Alzheimer's and Down Syndrome. However, signaling pathways regulating this form of learning are poorly understood. Previous studies have shown that the calcium-dependent exchange factor Ras-GRF1, an activator of Rac, Ras and R-Ras GTPases, is important for this form of learning and memory. Moreover, the ability to discriminate contexts was linked to the ability of Ras-GRF1 to promote high-frequency stimulation long-term potentiation (HFS-LTP) via the activation of p38 Map kinase. Here, we show that R-Ras is involved in this form of learning by using virally-delivered miRNAs targeting R-Ras into the CA1 region of the dorsal hippocampus and observing impaired contextual discrimination. Like the loss of GRF1, knockdown of R-Ras in the CA1 also impairs the induction of HFS-LTP and p38 Map kinase. Nevertheless, experiments indicate that this involvement of R-Ras in HFS-LTP that is required for contextual discrimination is independent of Ras-GRF1. Thus, R-Ras is a novel regulator of a form of hippocampal-dependent LTP as well as learning and memory that is affected in certain forms of neurodegenerative diseases. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Where You Look Matters for Body Perception: Preferred Gaze Location Contributes to the Body Inversion Effect

PubMed Central

McKean, Danielle L.; Tsao, Jack W.; Chan, Annie W.-Y.

2017-01-01

The Body Inversion Effect (BIE; reduced visual discrimination performance for inverted compared to upright bodies) suggests that bodies are visually processed configurally; however, the specific importance of head posture information in the BIE has been indicated in reports of BIE reduction for whole bodies with fixed head position and for headless bodies. Through measurement of gaze patterns and investigation of the causal relation of fixation location to visual body discrimination performance, the present study reveals joint contributions of feature and configuration processing to visual body discrimination. Participants predominantly gazed at the (body-centric) upper body for upright bodies and the lower body for inverted bodies in the context of an experimental paradigm directly comparable to that of prior studies of the BIE. Subsequent manipulation of fixation location indicates that these preferential gaze locations causally contributed to the BIE for whole bodies largely due to the informative nature of gazing at or near the head. Also, a BIE was detected for both whole and headless bodies even when fixation location on the body was held constant, indicating a role of configural processing in body discrimination, though inclusion of the head posture information was still highly discriminative in the context of such processing. Interestingly, the impact of configuration (upright and inverted) to the BIE appears greater than that of differential preferred gaze locations. PMID:28085894

Life satisfaction and trauma in clinical and non-clinical children living in a war-torn environment: A discriminant analysis.

PubMed

Veronese, Guido; Pepe, Alessandro

2017-07-01

The aim of this work was to discriminate between healthy children and children at risk of developing mental impairments by evaluating the impact on contextual and individual factors of a context characterized by war. We tested the hypothesis that a linear discriminant function composed of trauma, life satisfaction, and affect balance has the power to classify the children as community or clinical referred. Membership of the clinical-referred group was associated with poorer life satisfaction and higher levels of trauma. Community-referred profiles were associated with lesser trauma. Perceived life satisfaction regarding family and school was the main contributor to the discriminant function.

The influence of discrimination and fairness on collective self-esteem.

PubMed

Scheepers, Daan; Spears, Russell; Manstead, Antony S R; Doosje, Bertjan

2009-04-01

This article examines the influence of discrimination and fairness on collective self-esteem. Whereas social identity theory's self-esteem hypothesis emphasizes that discrimination can enhance self-esteem, the authors contend that this self-esteem advantage will actually reverse when groups are primed with the idea of engaging in a fair intergroup competition. They measured (Study 1) and manipulated (Study 2) discrimination and fairness in real (Study 1) and minimal (Study 2) groups, after which they manipulated the presence of an intergroup competition in both studies. Collective self-esteem served as the main dependent measure. Results indicated that when an intergroup competition was present or impending, previously expressed fairness (or less discrimination) was positively related to self-esteem, whereas discrimination was positively related to collective self-esteem in the absence of an intergroup competition. Results are discussed in terms of social identity theory and the importance of the broader social context for examining the relationship between discrimination and self-esteem.

One hundred years of discrimination research in the Journal of Applied Psychology: A sobering synopsis.

PubMed

Colella, Adrienne; Hebl, Mikki; King, Eden

2017-03-01

Employment discrimination-a legal, social, moral, and practical problem-has been a persistent focus of narrow scholarship in the Journal of Applied Psychology since its inception. Indeed, this article identifies the environmental characteristics, conceptual underpinnings, dominant methodologies, research questions and findings across 508 articles published on discrimination in the journal over the last 100 years. Emergent themes document signs of stability and change in 3 eras: an era wherein discrimination research was itself discriminatory (1917-1969), the heyday of discrimination research (1970-1989), and an era of unsteady progress (1990-2014). This synthesis suggests that, although increasingly sophisticated methodological approaches have been applied to this topic, the targets of focus and theories driving research have largely been static. Additionally, research published on discrimination in the Journal of Applied Psychology has often trailed too far behind the times. Specific recommendations for advancing the psychological study of employment discrimination in applied contexts are provided. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Social Context of Depressive Distress in Aging Transgender Adults

PubMed Central

White Hughto, Jaclyn M.; Reisner, Sari L.

2016-01-01

This study investigates the relationship between discrimination and mental health in aging transgender adults. Survey responses from 61 transgender adults above 50 (Mage = 57.7, SD = 5.8; 77.1% male-to-female; 78.7% White non-Hispanic) were analyzed. Multivariable logistic regression models examined the relationship between gender- and age-related discrimination, number of everyday discrimination experiences, and past-week depressive distress, adjusting for social support, sociodemographics, and other forms of discrimination. The most commonly attributed reasons for experiencing discrimination were related to gender (80.3%) and age (34.4%). More than half of participants (55.5%) met criteria for past-week depressive distress. In an adjusted multivariable model, gender-related discrimination and a greater number of everyday discrimination experiences were associated with increased odds of past-week depressive distress. Additional research is needed to understand the effects of aging and gender identity on depressive symptoms and develop interventions to safeguard the mental health of this vulnerable aging population. PMID:28380703

The context of discrimination: workplace conditions, institutional environments, and sex and race discrimination charges.

PubMed

Hirsh, C Elizabeth; Kornrich, Sabino

2008-03-01

This article explores the organizational conditions under which discrimination charges occur. Drawing on structural and organizational theories of the workplace, the authors demonstrate how organizational conditions affect workers' and regulatory agents' understandings of unlawful discrimination. Using a national sample of work establishments, matched to discrimination-charge data obtained from the Equal Employment Opportunity Commission (EEOC), the authors examine how characteristics of the workplace and institutional environment affect variation in the incidence of workers' charges of sex and race discrimination and in the subset of discrimination claims that are verified by EEOC investigators. The findings indicate that workplace conditions, including size, composition, and minority management, affect workers' charges as well as verified claims; the latter are also affected by institutional factors, such as affirmative action requirements, subsidiary status, and industrial sector. These results suggest that internal workplace conditions affect both workers' and regulatory agents' interpretations of potentially discriminatory experiences, while institutional conditions matter only for regulatory agents' interpretations of those events.

The Relationship between Perceived Discrimination and Generalized Anxiety Disorder among African Americans, Afro Caribbeans and non-Hispanic Whites

PubMed Central

Soto, José A.; Dawson-Andoh, Nana A.; BeLue, Rhonda

2010-01-01

The present study examined the relationship between frequency of race based and non-race based discrimination experiences and Generalized Anxiety Disorder (GAD) in a sample of 3,570 African Americans, 1,438 Afro Caribbeans, and 891 non-Hispanic Whites from the National Survey of American Life (NSAL). Because GAD and the experience of racial discrimination are both associated with symptoms of worry and tension, we expected race based discrimination to predict GAD prevalence for African Americans, but not other groups. We did not expect non-race based discrimination to predict GAD. Results showed that while more frequent experiences of non-race based discrimination predicted GAD for all groups, experiencing race based discrimination was associated with significantly higher odds of endorsing lifetime GAD for African Americans only. Results are interpreted in light of the different contexts that these three ethnic groups represent relative to their history within the United States as well as their present day circumstances. PMID:21041059

Social Context of Depressive Distress in Aging Transgender Adults.

PubMed

White Hughto, Jaclyn M; Reisner, Sari L

2016-11-01

This study investigates the relationship between discrimination and mental health in aging transgender adults. Survey responses from 61 transgender adults above 50 ( M age = 57.7, SD = 5.8; 77.1% male-to-female; 78.7% White non-Hispanic) were analyzed. Multivariable logistic regression models examined the relationship between gender- and age-related discrimination, number of everyday discrimination experiences, and past-week depressive distress, adjusting for social support, sociodemographics, and other forms of discrimination. The most commonly attributed reasons for experiencing discrimination were related to gender (80.3%) and age (34.4%). More than half of participants (55.5%) met criteria for past-week depressive distress. In an adjusted multivariable model, gender-related discrimination and a greater number of everyday discrimination experiences were associated with increased odds of past-week depressive distress. Additional research is needed to understand the effects of aging and gender identity on depressive symptoms and develop interventions to safeguard the mental health of this vulnerable aging population.

Discriminative Justice: Can Discrimination Be Just?

ERIC Educational Resources Information Center

Rocco, Tonette S.; Gallagher, Suzanne J.

2004-01-01

Educators of urban adults should attempt to deconstruct the dynamics in the classroom that replicate the social, political, and economic discourse of the dominant group. We must work to surface the complexity of diverse experiences represented by multiple oppressed groups.

Structural violence against Kothi-identified men who have sex with men in Chennai, India: a qualitative investigation.

PubMed

Chakrapani, Venkatesan; Newman, Peter A; Shunmugam, Murali; McLuckie, Alan; Melwin, Fredrick

2007-08-01

This qualitative investigation explored the experiences and contexts of stigma and discrimination among HIV-positive and high-risk kothi-identified men who have sex with men (MSM) in Chennai, India, and ramifications for HIV prevention. MSM were recruited through community agencies (n = 10) and public sex environments (n = 8), along with three key informants. In-depth, semistructured interviews were conducted, audiotaped, and transcribed. Narrative thematic analysis and a constant comparative method were used to identify themes. Findings revealed multiple intersecting social and institutional contexts and experiences of stigmatization, discrimination, and violence across police, community, family, and health care systems, as well as illuminating consequences for MSM. Multisystemic structural violence places kothis at extreme vulnerability for HIV infection and AIDS. Public mass media antidiscrimination campaigns, education and training of health care providers and police, funding of indigenous MSM community organizations, and decriminalization of consensual sex between same-sex adults may help to combat stigma, discrimination, and violence against MSM, which is fundamental to effective HIV prevention.

Sexism in schools.

PubMed

Leaper, Campbell; Brown, Christia Spears

2014-01-01

Sexism is gender-based prejudice or discrimination. As with other forms of prejudice and discrimination, it functions to maintain status and power differences between groups in society. One manifestation of sexism involves prejudice and discrimination against girls and women who seek to achieve in prestigious fields traditionally associated with males. Another manifestation of sexism, however, occurs when pressures are placed on boys and men to conform to traditional conceptions of masculinity. Over the last two decades, an increasing number of developmental and educational psychologists have become concerned about sexism directed toward children and adolescents in school contexts. Our chapter reviews the research on this topic. After providing an overview of different processes related to sexism, we examine how it is manifested in school contexts. Sexism is seen through gender-stereotyped biases against girls and boys in academic and athletic achievement. Also, it occurs through sexual harassment in social interactions. We also address factors related to children's awareness of sexism and coping responses to sexism. Finally, we consider possible ways to reduce sexism and foster effective coping in schools.

Pavlovian-conditioned alcohol-seeking behavior in rats is invigorated by the interaction between discrete and contextual alcohol cues: implications for relapse

PubMed Central

Remedios, Jessica; Woods, Catherine; Tardif, Catherine; Janak, Patricia H; Chaudhri, Nadia

2014-01-01

Introduction Drug craving can be independently stimulated by cues that are directly associated with drug intake (discrete drug cues), as well as by environmental contexts in which drug use occurs (contextual drug cues). We tested the hypothesis that the context in which a discrete alcohol-predictive cue is experienced can influence how robustly that cue stimulates alcohol-seeking behavior. Methods Male, Long-Evans rats received Pavlovian discrimination training (PDT) sessions in which one conditioned stimulus (CS+; 16 trials/session) was paired with ethanol (0.2 mL/CS+) and a second stimulus (CS−; 16 trials/session) was not. PDT occurred in a specific context, and entries into a fluid port where ethanol was delivered were measured during each CS. Next, rats were acclimated to an alternate (nonalcohol) context where cues and ethanol were withheld. Responses to the nonextinguished CS+ and CS− were then tested without ethanol in the alcohol-associated PDT context, the nonalcohol context or a third, novel context. Results Across PDT the CS+ elicited more port entries than the CS−, indicative of Pavlovian discrimination learning. At test, the CS+ elicited more port entries than the CS− in all three contexts: however, alcohol seeking driven by the CS+ was more robust in the alcohol-associated context. In a separate experiment, extinguishing the context-alcohol association did not influence subsequent CS+ responding but reduced alcohol seeking during non-CS+ intervals during a spontaneous recovery test. Conclusion These results indicate that alcohol-seeking behavior driven by a discrete Pavlovian alcohol cue is strongly invigorated by an alcohol context, and suggest that contexts may function as excitatory Pavlovian conditioned stimuli that directly trigger alcohol-seeking behavior. PMID:24683519

Features versus context: An approach for precise and detailed detection and delineation of faces and facial features.

PubMed

Ding, Liya; Martinez, Aleix M

2010-11-01

The appearance-based approach to face detection has seen great advances in the last several years. In this approach, we learn the image statistics describing the texture pattern (appearance) of the object class we want to detect, e.g., the face. However, this approach has had limited success in providing an accurate and detailed description of the internal facial features, i.e., eyes, brows, nose, and mouth. In general, this is due to the limited information carried by the learned statistical model. While the face template is relatively rich in texture, facial features (e.g., eyes, nose, and mouth) do not carry enough discriminative information to tell them apart from all possible background images. We resolve this problem by adding the context information of each facial feature in the design of the statistical model. In the proposed approach, the context information defines the image statistics most correlated with the surroundings of each facial component. This means that when we search for a face or facial feature, we look for those locations which most resemble the feature yet are most dissimilar to its context. This dissimilarity with the context features forces the detector to gravitate toward an accurate estimate of the position of the facial feature. Learning to discriminate between feature and context templates is difficult, however, because the context and the texture of the facial features vary widely under changing expression, pose, and illumination, and may even resemble one another. We address this problem with the use of subclass divisions. We derive two algorithms to automatically divide the training samples of each facial feature into a set of subclasses, each representing a distinct construction of the same facial component (e.g., closed versus open eyes) or its context (e.g., different hairstyles). The first algorithm is based on a discriminant analysis formulation. The second algorithm is an extension of the AdaBoost approach. We provide extensive experimental results using still images and video sequences for a total of 3,930 images. We show that the results are almost as good as those obtained with manual detection.

On the assimilation-discrimination relationship in American English adults’ French vowel learning1

PubMed Central

Levy, Erika S.

2009-01-01

A quantitative “cross-language assimilation overlap” method for testing predictions of the Perceptual Assimilation Model (PAM) was implemented to compare results of a discrimination experiment with the listeners’ previously reported assimilation data. The experiment examined discrimination of Parisian French (PF) front rounded vowels ∕y∕ and ∕œ∕. Three groups of American English listeners differing in their French experience (no experience [NoExp], formal experience [ModExp], and extensive formal-plus-immersion experience [HiExp]) performed discrimination of PF ∕y-u∕, ∕y-o∕, ∕œ-o∕, ∕œ-u∕, ∕y-i∕, ∕y-ɛ∕, ∕œ-ɛ∕, ∕œ-i∕, ∕y-œ∕, ∕u-i∕, and ∕a-ɛ∕. Vowels were in bilabial ∕rabVp∕ and alveolar ∕radVt∕ contexts. More errors were found for PF front vs back rounded vowel pairs (16%) than for PF front unrounded vs rounded pairs (2%). Overall, ModExp listeners did not perform more accurately (11% errors) than NoExp listeners (13% errors). Extensive immersion experience, however, was associated with fewer errors (3%) than formal experience alone, although discrimination of PF ∕y-u∕ remained relatively poor (12% errors) for HiExp listeners. More errors occurred on pairs involving front vs back rounded vowels in alveolar context (20% errors) than in bilabial (11% errors). Significant correlations were revealed between listeners’ assimilation overlap scores and their discrimination errors, suggesting that the PAM may be extended to second-language (L2) vowel learning. PMID:19894844

A double dissociation of dorsal and ventral hippocampal function on a learning and memory task mediated by the dorso-lateral striatum.

PubMed

McDonald, Robert J; Jones, Jana; Richards, Blake; Hong, Nancy S

2006-09-01

The objectives of this research were to further delineate the neural circuits subserving proposed memory-based behavioural subsystems in the hippocampal formation. These studies were guided by anatomical evidence showing a topographical organization of the hippocampal formation. Briefly, perpendicular to the medial/lateral entorhinal cortex division there is a second system of parallel circuits that separates the dorsal and ventral hippocampus. Recent work from this laboratory has provided evidence that the hippocampus incidentally encodes a context-specific inhibitory association during acquisition of a visual discrimination task. One question that emerges from this dataset is whether the dorsal or ventral hippocampus makes a unique contribution to this newly described function. Rats with neurotoxic lesions of the dorsal or ventral hippocampus were assessed on the acquisition of the visual discrimination task. Following asymptotic performance they were given reversal training in either the same or a different context from the original training. The results showed that the context-specific inhibition effect is mediated by a circuit that includes the ventral but not the dorsal hippocampus. Results from a control procedure showed that rats with either dorso-lateral striatum damage or dorsal hippocampal lesions were impaired on a tactile/spatial discrimination. Taken together, the results represent a double dissociation of learning and memory function between the ventral and dorsal hippocampus. The formation of an incidental inhibitory association was dependent on ventral but not dorsal hippocampal circuitry, and the opposite dependence was found for the spatial component of a tactile/spatial discrimination.

Social determinants of health--a comparative study of Bosnian adolescents in different cultural contexts.

PubMed

Sujoldzić, Anita; Peternel, Lana; Kulenović, Tarik; Terzić, Rifet

2006-12-01

This study investigated the effects of sociocultural contexts on health and the psychological well-being of immigrant adolescents, aged 15 to 18 years, originally from Bosnia and Herzegovina and now living as displaced persons either in Bosnia, or immigrants in Croatia and Austria. The study addresses the social determinants of health with a specific focus on five factors in the social environment that might have an influence on health status: gender, socio-economic status (SES), perceived discrimination and exposure to violence, social support and religious commitment. Dependent variables included self-rated health, a count of self-reported objective health problems and a range of indices of psychological well-being (somatic stress, anxiety, depression and self-esteem). The purpose of the study was to examine whether social risk factors have an effect on health, which factors mediate these effects on self-rated health and to assess whether these effects differ by gender Results indicate that perceived discrimination and violence are related to poor health through psychological stress as a major mechanism with stronger effects for girls in the study. Differences across the three socio-cultural contexts reveal the complexity and specificity of the relationships between analyzed factors as the association between discrimination and health was attenuated for some groups due to the protective resources of immigrants.

Workplace Victimization and Discrimination in China: A Nationwide Survey.

PubMed

Zhang, Huiping

2017-09-01

Workplace victimization and discrimination have been intensively studied in the West, especially on the antecedents and consequences of this phenomenon. Surprisingly, little is known about the incidence and associated health problems of workplace victimization and discrimination in contemporary China. Using a representative nationwide sample of 1,138 Chinese employees conducted in 2015, this study attempted to estimate the prevalence, risk factors, and associated consequences of workplace victimization and discrimination in China. It is found that the prevalence rate of preceding 5-year workplace discrimination and victimization was 33% and 12.9%, respectively. Male employees who perceived higher work gains were less likely to experience workplace victimization and those who had higher career efficacy and unemployment anxiety were more likely to experience job discrimination or victimization. Female employees who received tertiary education were less likely to experience job discrimination and being married tended not to experience workplace victimization. Perceived job discrimination had negative impact on male employees' job satisfaction as well as on female employees' happiness. The implications of these findings are finally discussed in the Chinese context.

Assessing Citizenship Behavior in Educational Contexts: The Role of Personality, Motivation, and Culture

ERIC Educational Resources Information Center

Chen, Sylvia Xiaohua; Carey, Timothy Patrick

2009-01-01

The present study developed a measure to assess citizenship behavior in educational settings and examined its antecedents and consequences in the cultural context. The results of this study provided discriminant validity for the newly extracted two-factor structure, that is, self-regulation and other-orientation. The authors identified both…

Postscript: Distinguishing between Temporal Context and Short-Term Store

ERIC Educational Resources Information Center

Howard, Marc W.; Kahana, Michael J.; Sederberg, Per B.

2008-01-01

Space does not allow us to make detailed rebuttals to Davelaar, Usher, Haarmann, and Goshen-Gottstein's criticisms of the temporal context model's (TCM-A's) ability to account for dissociations between immediate and delayed recall nor to explain how TCM could account for list discrimination experiments. We agree that future work is needed to reach…

Analysis of the Difficulty and Discrimination Indices of Multiple-Choice Questions According to Cognitive Levels in an Open and Distance Learning Context

ERIC Educational Resources Information Center

Koçdar, Serpil; Karadag, Nejdet; Sahin, Murat Dogan

2016-01-01

This is a descriptive study which intends to determine whether the difficulty and discrimination indices of the multiple-choice questions show differences according to cognitive levels of the Bloom's Taxonomy, which are used in the exams of the courses in a business administration bachelor's degree program offered through open and distance…

Natural Mentors, Racial Pride, and Academic Engagement among Black Adolescents: Resilience in the Context of Perceived Discrimination

ERIC Educational Resources Information Center

Wittrup, Audrey R.; Hussain, Saida B.; Albright, Jamie N.; Hurd, Noelle N.; Varner, Fatima A.; Mattis, Jacqueline S.

2016-01-01

The current study examined the potential of relational closeness in the natural mentoring relationships (NMRs) of Black students to counter and protect against the noxious effects of school-based discrimination on academic engagement. The study sample included 663 Black students between the ages of 12 and 19 (M = 14.96 years, SD = 1.81 years), all…

Testing a Model of Women's Personal Sense of Justice, Control, Well-Being, and Distress in the Context of Sexist Discrimination

ERIC Educational Resources Information Center

Fischer, Ann R.; Bolton Holz, Kenna

2010-01-01

Popular media convey notions that the United States is a postfeminist culture, where sexism is a thing of the past and gender equality prevails. Empirical data suggest otherwise. Further, links between group-based discrimination and psychological distress have been well documented (e.g., in bisexual and gay Latino men, African Americans, Asian…

AGED DOMINANT NEGATIVE p38α MAPK MICE ARE RESISTANT TO AGE-DEPENDENT DECLINE IN ADULT-NEUROGENESIS AND CONTEXT DISCRIMINATION FEAR CONDITIONING

PubMed Central

Cortez, IbDanelo; Bulavin, Dmitry V.; Wu, Ping; McGrath, Erica L; Cunningham, Kathryn A; Wakamiya, Maki; Papaconstantinou, John; Dineley, Kelly T

2018-01-01

A major aspect of mammalian aging is the decline in functional competence of many self-renewing cell types, including adult-born neuronal precursors. Since age-related senescence of self-renewal occurs simultaneously with chronic up-regulation of the p38MAPKalpha (p38α) signaling pathway, we used the dominant negative mouse model for attenuated p38α activity (DN-p38αAF/+ ) in which Thr180 and Tyr182 are mutated (T→A/Y→F) to prevent phosphorylation activation (DN-p38αAF/+) and kinase activity. As a result, aged DN-p38αAF/+ mice are resistant to age-dependent decline in proliferation and regeneration of several peripheral tissue progenitors when compared to wild-type littermates. Aging is the major risk factor for non-inherited forms of Alzheimer’s disease (AD); environmental and genetic risk factors that accelerate the senescence phenotype are thought to contribute to an individual’s relative risk. In the present study, we evaluated aged DN-p38αAF/+ and wildtype littermates in a series of behavioral paradigms to test if p38α mutant mice exhibit altered baseline abnormalities in neurological reflexes, locomotion, anxiety-like behavior, and age-dependent cognitive decline. While aged DN-p38αAF/+ and wildtype littermates appear equal in all tested baseline neurological and behavioral parameters, DN-p38αAF/+ exhibit superior context discrimination fear conditioning. Context discrimination is a cognitive task that is supported by proliferation and differentiation of adult-born neurons in the dentate gyrus of the hippocampus. Consistent with enhanced context discrimination in aged DN-p38αAF/+, we discovered enhanced production of adult-born neurons in the dentate gyrus of DN-p38αAF/+ mice compared to wildtype littermates. Our findings support the notion that p38α inhibition has therapeutic utility in aging diseases that affect cognition, such as AD. PMID:27765672

Aged dominant negative p38α MAPK mice are resistant to age-dependent decline in adult-neurogenesis and context discrimination fear conditioning.

PubMed

Cortez, IbDanelo; Bulavin, Dmitry V; Wu, Ping; McGrath, Erica L; Cunningham, Kathryn A; Wakamiya, Maki; Papaconstantinou, John; Dineley, Kelly T

2017-03-30

A major aspect of mammalian aging is the decline in functional competence of many self-renewing cell types, including adult-born neuronal precursors. Since age-related senescence of self-renewal occurs simultaneously with chronic up-regulation of the p38MAPKalpha (p38α) signaling pathway, we used the dominant negative mouse model for attenuated p38α activity (DN-p38α AF/+ ) in which Thr180 and Tyr182 are mutated (T→A/Y→F) to prevent phosphorylation activation (DN-p38α AF/+ ) and kinase activity. As a result, aged DN-p38α AF/+ mice are resistant to age-dependent decline in proliferation and regeneration of several peripheral tissue progenitors when compared to wild-type littermates. Aging is the major risk factor for non-inherited forms of Alzheimer's disease (AD); environmental and genetic risk factors that accelerate the senescence phenotype are thought to contribute to an individual's relative risk. In the present study, we evaluated aged DN-p38α AF/+ and wildtype littermates in a series of behavioral paradigms to test if p38α mutant mice exhibit altered baseline abnormalities in neurological reflexes, locomotion, anxiety-like behavior, and age-dependent cognitive decline. While aged DN-p38α AF/+ and wildtype littermates appear equal in all tested baseline neurological and behavioral parameters, DN-p38α AF/+ exhibit superior context discrimination fear conditioning. Context discrimination is a cognitive task that is supported by proliferation and differentiation of adult-born neurons in the dentate gyrus of the hippocampus. Consistent with enhanced context discrimination in aged DN-p38α AF/+ , we discovered enhanced production of adult-born neurons in the dentate gyrus of DN-p38α AF/+ mice compared to wildtype littermates. Our findings support the notion that p38α inhibition has therapeutic utility in aging diseases that affect cognition, such as AD. Copyright © 2016 Elsevier B.V. All rights reserved.

Discrimination, ethnic identity, and academic outcomes of Mexican immigrant children: the importance of school context.

PubMed

Brown, Christia Spears; Chu, Hui

2012-01-01

This study examined ethnic identity, perceptions of discrimination, and academic attitudes and performance of primarily first- and second-generation Mexican immigrant children living in a predominantly White community (N=204, 19 schools, mean age=9years). The study also examined schools' promotion of multiculturalism and teachers' attitudes about the value of diversity in predicting immigrant youth's attitudes and experiences. Results indicated that Latino immigrant children in this White community held positive and important ethnic identities and perceived low overall rates of discrimination. As expected, however, school and teacher characteristics were important in predicting children's perceptions of discrimination and ethnic identity, and moderated whether perceptions of discrimination and ethnic identity were related to attitudes about school and academic performance. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

Social identity change in response to discrimination.

PubMed

Perozzo, Cristina; de la Sablonnière, Roxane; Auger, Emilie; Caron-Diotte, Mathieu

2016-09-01

This study investigated the conditions under which discrimination can lead to social identity changes among members of a minority group. Both positive and negative relations between perceptions of discrimination and social identity have previously been reported. To explain the conflicting results and understand the complex reality of members of stigmatized groups, we argue that group-based emotions (e.g., group-based dissatisfaction) and ambiguity of discrimination cues (i.e., overt vs. ambiguous) need to be considered. We hypothesized that perceptions of discrimination would play a moderating role between group-based dissatisfaction and social identity change in a context of ambiguous, but not of overt, discrimination. The sample was comprised of 151 Arab Muslims living in the province of Quebec. Participants read fictitious newspaper articles portraying either overt (n = 76) or ambiguous (n = 75) discrimination towards in-group members. Results revealed that for participants in the overt discrimination condition, only group-based dissatisfaction was positively associated with social identity change. In contrast, for the participants in the ambiguous discrimination condition, those who perceived little discrimination and felt low group-based dissatisfaction reported a decrease in social identity. However, those who perceived low group discrimination and felt high group-based dissatisfaction reported a positive social identity change. © 2016 The British Psychological Society.

The inhibitory avoidance discrimination task to investigate accuracy of memory.

PubMed

Atucha, Erika; Roozendaal, Benno

2015-01-01

The present study was aimed at developing a new inhibitory avoidance task, based on training and/or testing rats in multiple contexts, to investigate accuracy of memory. In the first experiment, male Sprague-Dawley rats were given footshock in an inhibitory avoidance apparatus and, 48 h later, retention latencies of each rat were assessed in the training apparatus (Shock box) as well as in a novel, contextually modified, apparatus. Retention latencies in the Shock box were significantly longer than those in the Novel box, indicating accurate memory of the training context. When the noradrenergic stimulant yohimbine (0.3 mg/kg, sc) was administered after the training, 48-h retention latencies in the Shock box, but not Novel box, were increased, indicating that the noradrenergic activation enhanced memory of the training experience without reducing memory accuracy. In the second experiment, rats were trained on an inhibitory avoidance discrimination task: They were first trained in an inhibitory avoidance apparatus without footshock (Non-Shock box), followed 1 min later by footshock training in a contextually modified apparatus (Shock box). Forty-eight-hour retention latencies in the Shock and Non-Shock boxes did not differ from each other but were both significantly longer than those in a Novel box, indicating that rats remembered the two training contexts but did not have episodic-like memory of the association of footshock with the correct training context. When the interval between the two training episodes was increased to 2 min, rats showed accurate memory of the association of footshock with the training context. Yohimbine administered after the training also enhanced rats' ability to remember in which training context they had received actual footshock. These findings indicate that the inhibitory avoidance discrimination task is a novel variant of the well-established inhibitory avoidance task suitable to investigate accuracy of memory.

Discrimination and health inequities.

PubMed

Krieger, Nancy

2014-01-01

In 1999, only 20 studies in the public health literature employed instruments to measure self-reported experiences of discrimination. Fifteen years later, the number of empirical investigations on discrimination and health easily exceeds 500, with these studies increasingly global in scope and focused on major types of discrimination variously involving race/ethnicity, indigenous status, immigrant status, gender, sexuality, disability, and age, separately and in combination. And yet, as I also document, even as the number of investigations has dramatically expanded, the scope remains narrow: studies remain focused primarily on interpersonal discrimination, and scant research investigates the health impacts of structural discrimination, a gap consonant with the limited epidemiologic research on political systems and population health. Accordingly, to help advance the state of the field, this updated review article: (a) briefly reviews definitions of discrimination, illustrated with examples from the United States; (b) discusses theoretical insights useful for conceptualizing how discrimination can become embodied and produce health inequities, including via distortion of scientific knowledge; (c) concisely summarizes extant evidence--both robust and inconsistent--linking discrimination and health; and (d) addresses several key methodological controversies and challenges, including the need for careful attention to domains, pathways, level, and spatiotemporal scale, in historical context.

Factors Associated with Medical Doctors' Intentions to Discriminate Against Transgender Patients in Kuala Lumpur, Malaysia.

PubMed

Vijay, Aishwarya; Earnshaw, Valerie A; Tee, Ying Chew; Pillai, Veena; White Hughto, Jaclyn M; Clark, Kirsty; Kamarulzaman, Adeeba; Altice, Frederick L; Wickersham, Jeffrey A

2018-01-01

Transgender people are frequent targets of discrimination. Discrimination against transgender people in the context of healthcare can lead to poor health outcomes and facilitate the growth of health disparities. This study explores factors associated with medical doctors' intentions to discriminate against transgender people in Malaysia. A total of 436 physicians at two major university medical centers in Kuala Lumpur, Malaysia, completed an online survey. Sociodemographic characteristics, stigma-related constructs, and intentions to discriminate against transgender people were measured. Bivariate and multivariate linear regression were used to evaluate independent covariates of discrimination intent. Medical doctors who felt more fearful of transgender people and more personal shame associated with transgender people expressed greater intention to discriminate against transgender people, whereas doctors who endorsed the belief that transgender people deserve good care reported lower discrimination intent. Stigma-related constructs accounted for 42% of the variance and 8% was accounted for by sociodemographic characteristics. Constructs associated with transgender stigma play an important role in medical doctors' intentions to discriminate against transgender patients. Development of interventions to improve medical doctors' knowledge about and attitudes toward transgender people are necessary to reduce discriminatory intent in healthcare settings.

Factors Associated with Medical Doctors' Intentions to Discriminate Against Transgender Patients in Kuala Lumpur, Malaysia

PubMed Central

Vijay, Aishwarya; Earnshaw, Valerie A.; Tee, Ying Chew; Pillai, Veena; White Hughto, Jaclyn M.; Clark, Kirsty; Kamarulzaman, Adeeba; Altice, Frederick L.

2018-01-01

Abstract Purpose: Transgender people are frequent targets of discrimination. Discrimination against transgender people in the context of healthcare can lead to poor health outcomes and facilitate the growth of health disparities. This study explores factors associated with medical doctors' intentions to discriminate against transgender people in Malaysia. Methods: A total of 436 physicians at two major university medical centers in Kuala Lumpur, Malaysia, completed an online survey. Sociodemographic characteristics, stigma-related constructs, and intentions to discriminate against transgender people were measured. Bivariate and multivariate linear regression were used to evaluate independent covariates of discrimination intent. Results: Medical doctors who felt more fearful of transgender people and more personal shame associated with transgender people expressed greater intention to discriminate against transgender people, whereas doctors who endorsed the belief that transgender people deserve good care reported lower discrimination intent. Stigma-related constructs accounted for 42% of the variance and 8% was accounted for by sociodemographic characteristics. Conclusions: Constructs associated with transgender stigma play an important role in medical doctors' intentions to discriminate against transgender patients. Development of interventions to improve medical doctors' knowledge about and attitudes toward transgender people are necessary to reduce discriminatory intent in healthcare settings. PMID:29227183

Infectious diseases in the workplace: pointers for an ethical management policy.

PubMed

Hamblin, J

1990-01-01

Infectious diseases in the workplace can present difficult dilemmas for employers, who must balance the rights of infected employees against obligations to protect other employees from infection. Anti-discrimination legislation imposes additional obligations on employers to ensure that any steps taken in response to the risk of infectious disease do not amount to unlawful discrimination against employees who may be disease carriers. This paper analyses the operation of anti-discrimination in this context and points to ways in which employers can formulate an infectious diseases policy that is both ethically and legally defensible.

The Case for Absolute Ligand Discrimination: Modeling Information Processing and Decision by Immune T Cells

NASA Astrophysics Data System (ADS)

François, Paul; Altan-Bonnet, Grégoire

2016-03-01

Some cells have to take decision based on the quality of surroundings ligands, almost irrespective of their quantity, a problem we name "absolute discrimination". An example of absolute discrimination is recognition of not-self by immune T Cells. We show how the problem of absolute discrimination can be solved by a process called "adaptive sorting". We review several implementations of adaptive sorting, as well as its generic properties such as antagonism. We show how kinetic proofreading with negative feedback implement an approximate version of adaptive sorting in the immune context. Finally, we revisit the decision problem at the cell population level, showing how phenotypic variability and feedbacks between population and single cells are crucial for proper decision.

Reactive strategies in indirect reciprocity.

PubMed

Ohtsuki, Hisashi

2004-04-07

Evolution of reactive strategy of indirect reciprocity is discussed, where individuals interact with others through the one-shot Prisoner's Dilemma game, changing their partners in every round. We investigate all of the reactive strategies that are stochastic, including deterministic ones as special cases. First we study adaptive dynamics of reactive strategies by assuming monomorphic population. Results are very similar to the corresponding evolutionary dynamics of direct reciprocity. The discriminating strategy, which prescribes cooperation only with those who cooperated in the previous round, cannot be an outcome of the evolution. Next we examine the case where the population includes a diversity of strategies. We find that only the mean 'discriminatoriness' in the population is the parameter that affects the evolutionary dynamics. The discriminating strategy works as a promoter of cooperation there. However, it is again not the end point of the evolution. This is because retaliatory defection, which was prescribed by the discriminating strategy, is regarded as another defection toward the society. These results caution that we have to reconsider the role of retaliatory defection much more carefully.

Human action recognition based on point context tensor shape descriptor

NASA Astrophysics Data System (ADS)

Li, Jianjun; Mao, Xia; Chen, Lijiang; Wang, Lan

2017-07-01

Motion trajectory recognition is one of the most important means to determine the identity of a moving object. A compact and discriminative feature representation method can improve the trajectory recognition accuracy. This paper presents an efficient framework for action recognition using a three-dimensional skeleton kinematic joint model. First, we put forward a rotation-scale-translation-invariant shape descriptor based on point context (PC) and the normal vector of hypersurface to jointly characterize local motion and shape information. Meanwhile, an algorithm for extracting the key trajectory based on the confidence coefficient is proposed to reduce the randomness and computational complexity. Second, to decrease the eigenvalue decomposition time complexity, a tensor shape descriptor (TSD) based on PC that can globally capture the spatial layout and temporal order to preserve the spatial information of each frame is proposed. Then, a multilinear projection process is achieved by tensor dynamic time warping to map the TSD to a low-dimensional tensor subspace of the same size. Experimental results show that the proposed shape descriptor is effective and feasible, and the proposed approach obtains considerable performance improvement over the state-of-the-art approaches with respect to accuracy on a public action dataset.

In Situ Probe Science at Saturn

NASA Astrophysics Data System (ADS)

Atkinson, David H.; Lunine, Jonathan I.; Simon-Miller, Amy A.; Atreya, Sushil K.; Brinckerhoff, William B.; Colaprete, Anthony; Coustenis, Athena; Fletcher, Leigh N.; Guillot, Tristan; Lebreton, Jean-Pierre; Mahaffy, Paul; Mousis, Olivier; Orton, Glenn S.; Reh, Kim; Spilker, Linda J.; Spilker, Thomas R.; Webster, Chris R.

2014-05-01

A fundamental goal of solar system exploration is to understand the origin of the solar system, the initial stages, conditions, and processes by which the solar system formed, how the formation process was initiated, and the nature of the interstellar seed material from which the solar system was born. Key to understanding solar system formation and subsequent dynamical and chemical evolution is the origin and evolution of the giant planets and their atmospheres. Several theories have been put forward to explain the process of solar system formation, and the origin and evolution of the giant planets and their atmospheres. Each theory offers quantifiable predictions of the abundances of noble gases He, Ne, Ar, Kr, and Xe, and abundances of key isotopic ratios 4He/3He, D/H, 15N/14N, 18O/16O, and 13C/12C. Detection of certain disequilibrium species, diagnostic of deeper internal processes and dynamics of the atmosphere, would also help discriminate between competing theories. Many of the key atmospheric constituents needed to discriminate between alternative theories of giant planet formation and chemical evolution are either spectrally inactive or primarily located in the deeper atmosphere inaccessible to remote sensing from Earth, flyby, or orbiting spacecraft. Abundance measurements of these key constituents, including the two major molecular carriers of carbon, methane and carbon monoxide (neither of which condense in Saturn's atmosphere), sulfur which is expected to be well-mixed below the 4 to 5-bar ammonium hydrosulfide (NH4SH) cloud, and gradients of nitrogen below the NH4SH cloud and oxygen in the upper layers of the H2O and H2O-NH4 solution cloud, must be made in situ and can only be achieved by an entry probe descending through 10 bars. Measurements of the critical abundance profiles of these key constituents into the deeper well-mixed atmosphere must be complemented by measurements of the profiles of atmospheric structure and dynamics at high vertical resolution that also require in situ exploration. The atmospheres of the giant planets can also serve as laboratories to better understand the atmospheric chemistries, dynamics, processes, and climates on all planets in the solar system including Earth, and offer a context and provide a ground truth for exoplanets and exoplanetary systems. Additionally, Giant planets have long been thought to play a critical role in the development of potentially habitable planetary systems. In the context of giant planet science provided by the Galileo, Juno, and Cassini missions to Jupiter and Saturn, a small, relatively shallow Saturn probe capable of measuring abundances and isotopic ratios of key atmospheric constituents, and atmospheric structure including pressures, temperatures, dynamics, and cloud locations and properties not accessible by remote sensing can serve to test competing theories of solar system and giant planet origin, chemical, and dynamical evolution. Acknowledgements This research was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2013 California Institute of Technology. U.S. Government sponsorship acknowledged. O. Mousis acknowledges support from CNES.

The Effect of Context Change on Simple Acquisition Disappears with Increased Training

ERIC Educational Resources Information Center

Leon, Samuel P.; Abad, Maria J. F.; Rosas, Juan M.

2010-01-01

The goal of this experiment was to assess the impact that experience with a task has on the context specificity of the learning that occurs. Participants performed an instrumental task within a computer game where different responses were performed in the presence of discriminative stimuli to obtain reinforcers. The number of training trials (3,…

Ethnicity, Language-in-Education Policy and Linguistic Discrimination: Perspectives of Nepali Students in Hong Kong

ERIC Educational Resources Information Center

Thapa, Chura Bahadur; Adamson, Bob

2018-01-01

Educational issues in relation to ethnicity and language education policies have been underexplored in Asian contexts. In particular, issues related to ethnic and linguistic minority students have not received much attention in the post-colonial context of Hong Kong. This paper highlights challenges and tensions faced by Nepali ethnic minority…

Assessing the Double Phonemic Representation in Bilingual Speakers of Spanish and English: An Electrophysiological Study

ERIC Educational Resources Information Center

Garcia-Sierra, Adrian; Ramirez-Esparza, Nairan; Silva-Pereyra, Juan; Siard, Jennifer; Champlin, Craig A.

2012-01-01

Event Related Potentials (ERPs) were recorded from Spanish-English bilinguals (N = 10) to test pre-attentive speech discrimination in two language contexts. ERPs were recorded while participants silently read magazines in English or Spanish. Two speech contrast conditions were recorded in each language context. In the "phonemic in English"…

Dyadic Effects of Stigma and Discrimination on Distress in Chinese HIV Discordant Couples.

PubMed

Yu, Nancy Xiaonan; Chan, Cecilia L W; Zhang, Jianxin

2016-08-01

The present study investigated the dyadic effects of stigma and discrimination on distress in Chinese couples affected by HIV. Chinese people living with HIV (PLHIV) and their seronegative spouses (N = 119 couples) participated in this study. The PLHIV completed measures on stigma beliefs about being better off dead and dignity-related distress. The spouses completed measures on perceived discrimination and exclusion and caregiver distress. The results showed that there was no significant correlation between the PLHIV's stigma beliefs and the spouses' perceived discrimination and exclusion. The couples showed significant associations in their dignity-related distress and caregiver distress. Analyses using the actor-partner interdependence model showed that PLHIV's stigma beliefs and the spouses' perceived discrimination and exclusion both had significant actor and partner effects on distress within the dyad. Psychosocial interventions aiming for distress reduction in the context of HIV should tackle stigma and discrimination and target the couples rather than solely the patient or spouse.

Perceived discrimination and its association with psychological distress among newly arrived immigrants before and after September 11, 2001.

PubMed

Rousseau, Cécile; Hassan, Ghayda; Moreau, Nicolas; Thombs, Brett D

2011-05-01

We compared the evolution of perception of discrimination from 1998 to 2007 among recent Arab (Muslim and non-Muslim) and Haitian immigrants to Montreal; we also studied the association between perception of discrimination and psychological distress in 1998 and 2007. We conducted this cross-sectional comparative research with 2 samples: one recruited in 1998 (n = 784) and the other in 2007 (n = 432). The samples were randomly extracted from the registry of the Ministry of Immigration and Cultural Communities of Quebec. Psychological distress was measured with the Hopkins Symptom Checklist-25. The perception of discrimination increased from 1998 to 2007 among the Arab Muslim, Arab non-Muslim, and Haitian groups. Muslim Arabs experienced a significant increase in psychological distress associated with discrimination from 1998 to 2007. These results confirm an increase in perception of discrimination and psychological distress among Arab Muslim recent immigrant communities after September 11, 2001, and highlight the importance this context may have for other immigrant groups.

[Discrimination and homophobia associated to the human immunodeficiency virus epidemic].

PubMed

Orozco-Núñez, Emanuel; Alcalde-Rabanal, Jacqueline Elizabeth; Ruiz-Larios, José Arturo; Sucilla-Pérez, Héctor; García-Cerde, Rodrigo

2015-01-01

To describe a political mapping on discrimination and homophobia associated to human immunodeficiency virus (HIV) in the context of public institutions in Mexico. The political mapping was conducted in six Mexican states. Stakeholders who were involved in HIV actions from public and private sectors were included. Semistructured interviews were applied to explore homophobia and discrimination associated with HIV. Information was systematized using the Policy Maker software, which is a good support for analyzing health policies. Discriminatory and homophobic practices in the public domain occurred, damaging people´s integrity via insults, derision and hate crimes. Most stakeholders expressed a supportive position to prevent discrimination and homophobia and some of them had great influence on policy-making decisions. It was found that state policy frameworks are less specific in addressing these issues. Homophobia and discrimination associated to HIV are still considered problematic in Mexico. Homophobia is a very sensitive issue that requires further attention. Also, an actual execution of governmental authority requires greater enforcement of laws against discrimination and homophobia.

Modeling Collective Animal Behavior with a Cognitive Perspective: A Methodological Framework

PubMed Central

Weitz, Sebastian; Blanco, Stéphane; Fournier, Richard; Gautrais, Jacques; Jost, Christian; Theraulaz, Guy

2012-01-01

The last decades have seen an increasing interest in modeling collective animal behavior. Some studies try to reproduce as accurately as possible the collective dynamics and patterns observed in several animal groups with biologically plausible, individual behavioral rules. The objective is then essentially to demonstrate that the observed collective features may be the result of self-organizing processes involving quite simple individual behaviors. Other studies concentrate on the objective of establishing or enriching links between collective behavior researches and cognitive or physiological ones, which then requires that each individual rule be carefully validated. Here we discuss the methodological consequences of this additional requirement. Using the example of corpse clustering in ants, we first illustrate that it may be impossible to discriminate among alternative individual rules by considering only observational data collected at the group level. Six individual behavioral models are described: They are clearly distinct in terms of individual behaviors, they all reproduce satisfactorily the collective dynamics and distribution patterns observed in experiments, and we show theoretically that it is strictly impossible to discriminate two of these models even in the limit of an infinite amount of data whatever the accuracy level. A set of methodological steps are then listed and discussed as practical ways to partially overcome this problem. They involve complementary experimental protocols specifically designed to address the behavioral rules successively, conserving group-level data for the overall model validation. In this context, we highlight the importance of maintaining a sharp distinction between model enunciation, with explicit references to validated biological concepts, and formal translation of these concepts in terms of quantitative state variables and fittable functional dependences. Illustrative examples are provided of the benefits expected during the often long and difficult process of refining a behavioral model, designing adapted experimental protocols and inversing model parameters. PMID:22761685

Modeling collective animal behavior with a cognitive perspective: a methodological framework.

PubMed

Weitz, Sebastian; Blanco, Stéphane; Fournier, Richard; Gautrais, Jacques; Jost, Christian; Theraulaz, Guy

2012-01-01

The last decades have seen an increasing interest in modeling collective animal behavior. Some studies try to reproduce as accurately as possible the collective dynamics and patterns observed in several animal groups with biologically plausible, individual behavioral rules. The objective is then essentially to demonstrate that the observed collective features may be the result of self-organizing processes involving quite simple individual behaviors. Other studies concentrate on the objective of establishing or enriching links between collective behavior researches and cognitive or physiological ones, which then requires that each individual rule be carefully validated. Here we discuss the methodological consequences of this additional requirement. Using the example of corpse clustering in ants, we first illustrate that it may be impossible to discriminate among alternative individual rules by considering only observational data collected at the group level. Six individual behavioral models are described: They are clearly distinct in terms of individual behaviors, they all reproduce satisfactorily the collective dynamics and distribution patterns observed in experiments, and we show theoretically that it is strictly impossible to discriminate two of these models even in the limit of an infinite amount of data whatever the accuracy level. A set of methodological steps are then listed and discussed as practical ways to partially overcome this problem. They involve complementary experimental protocols specifically designed to address the behavioral rules successively, conserving group-level data for the overall model validation. In this context, we highlight the importance of maintaining a sharp distinction between model enunciation, with explicit references to validated biological concepts, and formal translation of these concepts in terms of quantitative state variables and fittable functional dependences. Illustrative examples are provided of the benefits expected during the often long and difficult process of refining a behavioral model, designing adapted experimental protocols and inversing model parameters.

Transfer of learning between unimanual and bimanual rhythmic movement coordination: transfer is a function of the task dynamic.

PubMed

Snapp-Childs, Winona; Wilson, Andrew D; Bingham, Geoffrey P

2015-07-01

Under certain conditions, learning can transfer from a trained task to an untrained version of that same task. However, it is as yet unclear what those certain conditions are or why learning transfers when it does. Coordinated rhythmic movement is a valuable model system for investigating transfer because we have a model of the underlying task dynamic that includes perceptual coupling between the limbs being coordinated. The model predicts that (1) coordinated rhythmic movements, both bimanual and unimanual, are organised with respect to relative motion information for relative phase in the coupling function, (2) unimanual is less stable than bimanual coordination because the coupling is unidirectional rather than bidirectional, and (3) learning a new coordination is primarily about learning to perceive and use the relevant information which, with equal perceptual improvement due to training, yields equal transfer of learning from bimanual to unimanual coordination and vice versa [but, given prediction (2), the resulting performance is also conditioned by the intrinsic stability of each task]. In the present study, two groups were trained to produce 90° either unimanually or bimanually, respectively, and tested in respect to learning (namely improved performance in the trained 90° coordination task and improved visual discrimination of 90°) and transfer of learning (to the other, untrained 90° coordination task). Both groups improved in the task condition in which they were trained and in their ability to visually discriminate 90°, and this learning transferred to the untrained condition. When scaled by the relative intrinsic stability of each task, transfer levels were found to be equal. The results are discussed in the context of the perception-action approach to learning and performance.

Predicting dynamic range and intensity discrimination for electrical pulse-train stimuli using a stochastic auditory nerve model: the effects of stimulus noise.

PubMed

Xu, Yifang; Collins, Leslie M

2005-06-01

This work investigates dynamic range and intensity discrimination for electrical pulse-train stimuli that are modulated by noise using a stochastic auditory nerve model. Based on a hypothesized monotonic relationship between loudness and the number of spikes elicited by a stimulus, theoretical prediction of the uncomfortable level has previously been determined by comparing spike counts to a fixed threshold, Nucl. However, no specific rule for determining Nucl has been suggested. Our work determines the uncomfortable level based on the excitation pattern of the neural response in a normal ear. The number of fibers corresponding to the portion of the basilar membrane driven by a stimulus at an uncomfortable level in a normal ear is related to Nucl at an uncomfortable level of the electrical stimulus. Intensity discrimination limens are predicted using signal detection theory via the probability mass function of the neural response and via experimental simulations. The results show that the uncomfortable level for pulse-train stimuli increases slightly as noise level increases. Combining this with our previous threshold predictions, we hypothesize that the dynamic range for noise-modulated pulse-train stimuli should increase with additive noise. However, since our predictions indicate that intensity discrimination under noise degrades, overall intensity coding performance may not improve significantly.

Lexical exposure to native language dialects can improve non-native phonetic discrimination.

PubMed

Olmstead, Annie J; Viswanathan, Navin

2018-04-01

Nonnative phonetic learning is an area of great interest for language researchers, learners, and educators alike. In two studies, we examined whether nonnative phonetic discrimination of Hindi dental and retroflex stops can be improved by exposure to lexical items bearing the critical nonnative stops. We extend the lexical retuning paradigm of Norris, McQueen, and Cutler (Cognitive Psychology, 47, 204-238, 2003) by having naive American English (AE)-speaking participants perform a pretest-training-posttest procedure. They performed an AXB discrimination task with the Hindi retroflex and dental stops before and after transcribing naturally produced words from an Indian English speaker that either contained these tokens or not. Only those participants who heard words with the critical nonnative phones improved in their posttest discrimination. This finding suggests that exposure to nonnative phones in native lexical contexts supports learning of difficult nonnative phonetic discrimination.

The visual discrimination of negative facial expressions by younger and older adults.

PubMed

Mienaltowski, Andrew; Johnson, Ellen R; Wittman, Rebecca; Wilson, Anne-Taylor; Sturycz, Cassandra; Norman, J Farley

2013-04-05

Previous research has demonstrated that older adults are not as accurate as younger adults at perceiving negative emotions in facial expressions. These studies rely on emotion recognition tasks that involve choosing between many alternatives, creating the possibility that age differences emerge for cognitive rather than perceptual reasons. In the present study, an emotion discrimination task was used to investigate younger and older adults' ability to visually discriminate between negative emotional facial expressions (anger, sadness, fear, and disgust) at low (40%) and high (80%) expressive intensity. Participants completed trials blocked by pairs of emotions. Discrimination ability was quantified from the participants' responses using signal detection measures. In general, the results indicated that older adults had more difficulty discriminating between low intensity expressions of negative emotions than did younger adults. However, younger and older adults did not differ when discriminating between anger and sadness. These findings demonstrate that age differences in visual emotion discrimination emerge when signal detection measures are used but that these differences are not uniform and occur only in specific contexts.

The shield of professional status: Comparing internationally educated nurses' and international medical graduates' experiences of discrimination.

PubMed

Neiterman, Elena; Bourgeault, Ivy Lynn

2015-11-01

This article examines the intersecting roles of gender, ethnicity, and professional status in shaping the experiences of internationally educated health professionals in Canada. The article is based on 140 semi-structured qualitative interviews with internationally trained nurses and physicians who came to Canada within past 10 years with the intention to practice their profession. Describing the challenging process of professional integration in Canada, our participants highlighted incidents of discrimination they experienced along the way. Although some of the participants from both professional groups experienced racial discrimination, the context of those experiences differed. Physicians rarely reported instances of discrimination in communication with patients or nurses. Instead, they were concerned with instances of discrimination within their own professional group. Nurses, on the other hand, reported discrimination at the hands of patients and their families as well as racialization by physicians, management, and other nurses. We conclude our article with a reflection on the role that gender and professional status play in shaping the experiences of ethnic discrimination of internationally educated health professionals. © The Author(s) 2015.

Perceptions of Race/Ethnicity-Based Discrimination: A Review of Measures and Evaluation of their Usefulness for the Health Care Setting

PubMed Central

Kressin, Nancy R.; Raymond, Kristal L.; Manze, Meredith

2010-01-01

Background To assess discrimination in health care, reliable, valid, and comprehensive measures of racism/discrimination are needed. Objective To review literature on measures of perceived race/ethnicity-based discrimination and evaluate their characteristics and usefulness in assessing discrimination from health care providers. Methods Literature review of measures of perceived race/ethnicity-based discrimination (1966–2007), using MEDLINE, PsycINFO, and Social Science Citation Index. Results We identified 34 measures of racism/discrimination; 16 specifically assessed dynamics in the health care setting. Few measures were theoretically based; most assessed only general dimensions of racism and focused specifically on the experiences of African American patients. Acceptable psychometric properties were documented for about half of the instruments. Conclusions Additional measures are needed for detailed assessments of perceived discrimination in the health care setting; they should be relevant for a wide variety of racial/ethnic groups, and they must assess how racism/discrimination affects health care decision making and treatments offered. PMID:18677066

Multiple Levels of Suffering

PubMed Central

Kiley, Kasey B.; Haywood, Carlton; Bediako, Shawn M.; Lanzkron, Sophie; Carroll, C. Patrick; Buenaver, Luis F.; Pejsa, Megan; Edwards, Robert R.; Haythornthwaite, Jennifer A.; Campbell, Claudia M.

2016-01-01

Objective: People living with sickle cell disease (SCD) experience severe episodic and chronic pain and frequently report poor interpersonal treatment within health-care settings. In this particularly relevant context, we examined the relationship between perceived discrimination and both clinical and laboratory pain. Methods: Seventy-one individuals with SCD provided self-reports of experiences with discrimination in health-care settings and clinical pain severity, and completed a psychophysical pain testing battery in the laboratory. Results: Discrimination in health-care settings was correlated with greater clinical pain severity and enhanced sensitivity to multiple laboratory-induced pain measures, as well as stress, depression, and sleep. After controlling for relevant covariates, discrimination remained a significant predictor of mechanical temporal summation (a marker of central pain facilitation), but not clinical pain severity or suprathreshold heat pain response. Furthermore, a significant interaction between experience with discrimination and clinical pain severity was associated with mechanical temporal summation; increased experience with discrimination was associated with an increased correlation between clinical pain severity and temporal summation of pain. Discussion: Perceived discrimination within health-care settings was associated with pain facilitation. These findings suggest that discrimination may be related to increased central sensitization among SCD patients, and more broadly that health-care social environments may interact with pain pathophysiology. PMID:26889615

Discrimination of nuclear spin isomers exploiting the excited state dynamics of a quinodimethane derivative

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

Obaid, Rana; Faculty of Pharmacy, Al-Quds University, Abu Dis, Palestine; Kinzel, Daniel

2014-10-28

Despite the concept of nuclear spin isomers (NSIs) exists since the early days of quantum mechanics, only few approaches have been suggested to separate different NSIs. Here, a method is proposed to discriminate different NSIs of a quinodimethane derivative using its electronic excited state dynamics. After electronic excitation by a laser field with femtosecond time duration, a difference in the behavior of several quantum mechanical operators can be observed. A pump-probe experimental approach for separating these different NSIs is then proposed.

Pre-migration Trauma Exposure and Psychological Distress for Asian American Immigrants: Linking the Pre- and Post-migration Contexts.

PubMed

Li, Miao; Anderson, James G

2016-08-01

Drawing on the life course perspective and the assumptive world theory, this paper examines whether pre-migration trauma exposure is associated with psychological distress through post-migration perceived discrimination for Asian American immigrants. The study is based on cross-sectional data from the National Latino and Asian American Study (N = 1639). Structural equation model is used to estimate the relationship between pre-migration trauma, post-migration perceived discrimination, and psychological distress. Additional models are estimated to explore possible variations across ethnic groups as well as across different types of pre-migration trauma experience. Pre-migration trauma exposure is associated with higher levels of psychological distress, both directly and indirectly through higher level of perceived discrimination, even after controlling for demographic/acculturative factors and post-migration trauma exposure. This pattern holds for the following sub-types of pre-migration trauma: political trauma, crime victimization, physical violence, accidental trauma, and relational trauma. Multi-group analyses show that this pattern holds for all Asian immigrant subgroups except the Vietnamese. Studies of immigrant mental health primarily focus on post-migration stressors. Few studies have considered the link between pre- and post-migration contexts in assessing mental health outcomes. The study illustrates the usefulness of bridging the pre- and post-migration context in identifying the mental health risks along the immigrant life course.

Determinants of STD epidemics: implications for phase appropriate intervention strategies.

PubMed

Aral, S O

2002-04-01

Determinants of evolving epidemics of sexually transmitted diseases (STD) are equally influenced by the evolution of the STD epidemics themselves and by the evolution of human societies. A temporal approach to STD transmission dynamics suggests the need to monitor infectivity, rate of exposure between infected and susceptible individuals, and duration of infectiousness in societies. Different indicators may be used to monitor rate of exposure in the general population and in core groups. In addition, underlying determinants of STD epidemics such as poverty, inequality, racial/ethnic discrimination, unemployment, sex ratio, volume of migration, and health care coverage and quality are important variables to monitor through a surveillance system focused on social context. Ongoing large scale societal changes including urbanisation, globalisation, increasing inequality, and increasing volume of migrant populations may affect the evolution of STD epidemics. Globalised STD epidemics could pose a major challenge to local public health systems.

Felt stigma and obesity: introducing the generalized other.

PubMed

Barlösius, Eva; Philipps, Axel

2015-04-01

People with a big body are tainted in western societies. Although most research on obesity occurs in the medical context, few studies investigate characteristics and effects of feelings and fears related to the fat stigma in the absence of overt discrimination. By linking Norbert Elias's and George H. Mead's theoretical frameworks, this paper offers a different approach to understanding and investigating felt stigma. The study is based on secondary data (25 semistructured interviews with children and adolescents). It explores internalized societal perspectives on overweight and obesity and inquires into the way in which interviewees handle the blame frame of personal responsibility during their interview. The preliminary findings suggest that specific forms of managing one's self-presentation in interviews indicate felt stigma. Consequently, the paper argues for an analytical approach that extends the focus on the content of interviews to include its dynamics. Copyright © 2015 Elsevier Ltd. All rights reserved.

Limiting Energy Dissipation Induces Glassy Kinetics in Single-Cell High-Precision Responses

PubMed Central

Das, Jayajit

2016-01-01

Single cells often generate precise responses by involving dissipative out-of-thermodynamic-equilibrium processes in signaling networks. The available free energy to fuel these processes could become limited depending on the metabolic state of an individual cell. How does limiting dissipation affect the kinetics of high-precision responses in single cells? I address this question in the context of a kinetic proofreading scheme used in a simple model of early-time T cell signaling. Using exact analytical calculations and numerical simulations, I show that limiting dissipation qualitatively changes the kinetics in single cells marked by emergence of slow kinetics, large cell-to-cell variations of copy numbers, temporally correlated stochastic events (dynamic facilitation), and ergodicity breaking. Thus, constraints in energy dissipation, in addition to negatively affecting ligand discrimination in T cells, can create a fundamental difficulty in determining single-cell kinetics from cell-population results. PMID:26958894

An intersectional approach for understanding perceived discrimination and psychological well-being among African American and Caribbean Black youth.

PubMed

Seaton, Eleanor K; Caldwell, Cleopatra H; Sellers, Robert M; Jackson, James S

2010-09-01

The present study examined whether combinations of ethnicity, gender, and age moderated the association between perceived discrimination and psychological well-being indicators (depressive symptoms, self-esteem, and life satisfaction) in a nationally representative sample of Black youth. The data were from the National Survey of American Life, which includes 810 African American and 360 Caribbean Black adolescents. The results indicated main effects such that perceived discrimination was linked to increased depressive symptoms and decreased self-esteem and life satisfaction. Additionally, there were significant interactions for ethnicity, gender, and race. Specifically, older Caribbean Black female adolescents exhibited higher depressive symptoms and lower life satisfaction in the context of high levels of perceived discrimination compared with older African American male adolescents.

FUNCTIONAL LIMITATION AND DEPRESSIVE SYMPTOMATOLOGY: CONSIDERING PERCEIVED STIGMA AND DISCRIMINATION WITHIN A STRESS AND COPING FRAMEWORK

PubMed Central

Brown, Robyn Lewis

2016-01-01

This study examines whether perceived stigma and discrimination moderate the associations between functional limitation, psychosocial coping resources, and depressive symptoms among people with physical disabilities. Using two waves of data from a large community study including a representative sample of persons with physical disabilities (N=417), an SEM-based moderated mediation analysis was performed. Mediation tests demonstrate that mastery significantly mediates the association between functional limitation and depressive symptoms over the study period. Moderated mediation tests reveal that the linkage between functional limitation and mastery varies as a function of perceived stigma and experiences of major discrimination and day-to-day discrimination, however. The implications of these findings are discussed in the context of the stress and coping literature. PMID:28497112

Men ask more questions than women at a scientific conference

PubMed Central

Sutherland, William J.; Johnston, Alison

2017-01-01

Gender inequity in science and academia, especially in senior positions, is a recognised problem. The reasons are poorly understood, but include the persistence of historical gender ratios, discrimination and other factors, including gender-based behavioural differences. We studied participation in a professional context by observing question-asking behaviour at a large international conference with a clear equality code of conduct that prohibited any form of discrimination. Accounting for audience gender ratio, male attendees asked 1.8 questions for each question asked by a female attendee. Amongst only younger researchers, male attendees also asked 1.8 questions per female question, suggesting the pattern cannot be attributed to the temporary problem of demographic inertia. We link our findings to the ‘chilly’ climate for women in STEM, including wider experiences of discrimination likely encountered by women throughout their education and careers. We call for a broader and coordinated approach to understanding and addressing the barriers to women and other under-represented groups. We encourage the scientific community to recognise the context in which these gender differences occur, and evaluate and develop methods to support full participation from all attendees. PMID:29036191

Men ask more questions than women at a scientific conference.

PubMed

Hinsley, Amy; Sutherland, William J; Johnston, Alison

2017-01-01

Gender inequity in science and academia, especially in senior positions, is a recognised problem. The reasons are poorly understood, but include the persistence of historical gender ratios, discrimination and other factors, including gender-based behavioural differences. We studied participation in a professional context by observing question-asking behaviour at a large international conference with a clear equality code of conduct that prohibited any form of discrimination. Accounting for audience gender ratio, male attendees asked 1.8 questions for each question asked by a female attendee. Amongst only younger researchers, male attendees also asked 1.8 questions per female question, suggesting the pattern cannot be attributed to the temporary problem of demographic inertia. We link our findings to the 'chilly' climate for women in STEM, including wider experiences of discrimination likely encountered by women throughout their education and careers. We call for a broader and coordinated approach to understanding and addressing the barriers to women and other under-represented groups. We encourage the scientific community to recognise the context in which these gender differences occur, and evaluate and develop methods to support full participation from all attendees.

Disturbance by optimal discrimination

NASA Astrophysics Data System (ADS)

Kawakubo, Ryûitirô; Koike, Tatsuhiko

2018-03-01

We discuss the disturbance by measurements which unambiguously discriminate between given candidate states. We prove that such an optimal measurement necessarily changes distinguishable states indistinguishable when the inconclusive outcome is obtained. The result was previously shown by Chefles [Phys. Lett. A 239, 339 (1998), 10.1016/S0375-9601(98)00064-4] under restrictions on the class of quantum measurements and on the definition of optimality. Our theorems remove these restrictions and are also applicable to infinitely many candidate states. Combining with our previous results, one can obtain concrete mathematical conditions for the resulting states. The method may have a wide variety of applications in contexts other than state discrimination.

Graphical methods for the sensitivity analysis in discriminant analysis

DOE PAGES

Kim, Youngil; Anderson-Cook, Christine M.; Dae-Heung, Jang

2015-09-30

Similar to regression, many measures to detect influential data points in discriminant analysis have been developed. Many follow similar principles as the diagnostic measures used in linear regression in the context of discriminant analysis. Here we focus on the impact on the predicted classification posterior probability when a data point is omitted. The new method is intuitive and easily interpretative compared to existing methods. We also propose a graphical display to show the individual movement of the posterior probability of other data points when a specific data point is omitted. This enables the summaries to capture the overall pattern ofmore » the change.« less

Discrimination in measures of knowledge monitoring accuracy

PubMed Central

Was, Christopher A.

2014-01-01

Knowledge monitoring predicts academic outcomes in many contexts. However, measures of knowledge monitoring accuracy are often incomplete. In the current study, a measure of students’ ability to discriminate known from unknown information as a component of knowledge monitoring was considered. Undergraduate students’ knowledge monitoring accuracy was assessed and used to predict final exam scores in a specific course. It was found that gamma, a measure commonly used as the measure of knowledge monitoring accuracy, accounted for a small, but significant amount of variance in academic performance whereas the discrimination and bias indexes combined to account for a greater amount of variance in academic performance. PMID:25339979

A single-rate context-dependent learning process underlies rapid adaptation to familiar object dynamics.

PubMed

Ingram, James N; Howard, Ian S; Flanagan, J Randall; Wolpert, Daniel M

2011-09-01

Motor learning has been extensively studied using dynamic (force-field) perturbations. These induce movement errors that result in adaptive changes to the motor commands. Several state-space models have been developed to explain how trial-by-trial errors drive the progressive adaptation observed in such studies. These models have been applied to adaptation involving novel dynamics, which typically occurs over tens to hundreds of trials, and which appears to be mediated by a dual-rate adaptation process. In contrast, when manipulating objects with familiar dynamics, subjects adapt rapidly within a few trials. Here, we apply state-space models to familiar dynamics, asking whether adaptation is mediated by a single-rate or dual-rate process. Previously, we reported a task in which subjects rotate an object with known dynamics. By presenting the object at different visual orientations, adaptation was shown to be context-specific, with limited generalization to novel orientations. Here we show that a multiple-context state-space model, with a generalization function tuned to visual object orientation, can reproduce the time-course of adaptation and de-adaptation as well as the observed context-dependent behavior. In contrast to the dual-rate process associated with novel dynamics, we show that a single-rate process mediates adaptation to familiar object dynamics. The model predicts that during exposure to the object across multiple orientations, there will be a degree of independence for adaptation and de-adaptation within each context, and that the states associated with all contexts will slowly de-adapt during exposure in one particular context. We confirm these predictions in two new experiments. Results of the current study thus highlight similarities and differences in the processes engaged during exposure to novel versus familiar dynamics. In both cases, adaptation is mediated by multiple context-specific representations. In the case of familiar object dynamics, however, the representations can be engaged based on visual context, and are updated by a single-rate process.

Multiple Levels of Suffering: Discrimination in Health-Care Settings is Associated With Enhanced Laboratory Pain Sensitivity in Sickle Cell Disease.

PubMed

Mathur, Vani A; Kiley, Kasey B; Haywood, Carlton; Bediako, Shawn M; Lanzkron, Sophie; Carroll, C Patrick; Buenaver, Luis F; Pejsa, Megan; Edwards, Robert R; Haythornthwaite, Jennifer A; Campbell, Claudia M

2016-12-01

People living with sickle cell disease (SCD) experience severe episodic and chronic pain and frequently report poor interpersonal treatment within health-care settings. In this particularly relevant context, we examined the relationship between perceived discrimination and both clinical and laboratory pain. Seventy-one individuals with SCD provided self-reports of experiences with discrimination in health-care settings and clinical pain severity, and completed a psychophysical pain testing battery in the laboratory. Discrimination in health-care settings was correlated with greater clinical pain severity and enhanced sensitivity to multiple laboratory-induced pain measures, as well as stress, depression, and sleep. After controlling for relevant covariates, discrimination remained a significant predictor of mechanical temporal summation (a marker of central pain facilitation), but not clinical pain severity or suprathreshold heat pain response. Furthermore, a significant interaction between experience with discrimination and clinical pain severity was associated with mechanical temporal summation; increased experience with discrimination was associated with an increased correlation between clinical pain severity and temporal summation of pain. Perceived discrimination within health-care settings was associated with pain facilitation. These findings suggest that discrimination may be related to increased central sensitization among SCD patients, and more broadly that health-care social environments may interact with pain pathophysiology.

Perceived Housing Discrimination and Self-Reported Health: How Do Neighborhood Features Matter?

PubMed

Yang, Tse-Chuan; Chen, Danhong; Park, Kiwoong

2016-12-01

While the association between perceived discrimination and health has been investigated, little is known about whether and how neighborhood characteristics moderate this association. We situate discrimination in the housing context and use relative deprivation and social capital perspectives to fill the knowledge gap. We applied multilevel logistic modeling to 9,842 adults in 830 neighborhoods in Philadelphia to examine three hypotheses. First, the detrimental effect of discrimination on self-reported health was underestimated without considering neighborhood features as moderators. The estimated coefficient (β) increased from approximately 0.02 to 1.84 or higher. Second, the negative association between discrimination and self-reported health was enhanced when individuals with discrimination experience lived in neighborhoods with higher housing values (β = 0.42). Third, the adverse association of discrimination with self-reported health was attenuated when people reporting discrimination resided in neighborhoods marked by higher income inequality (β = -4.34) and higher concentrations of single-parent households with children (β = -0.03) and minorities (β = -0.01). We not only confirmed the moderating roles of neighborhood characteristics, but also suggested that the relative deprivation and social capital perspectives could be used to understand how perceived housing discrimination affects self-reported health via neighborhood factors.

Perceived Housing Discrimination and Self-reported Health: How Do Neighborhood Features Matter?

PubMed Central

Yang, Tse-Chuan; Chen, Danhong; Park, Kiwoong

2016-01-01

Background While the association between perceived discrimination and health has been investigated, little is known about whether and how neighborhood characteristics moderate this association. Purpose We situate discrimination in the housing context and use relative deprivation and social capital perspectives to fill the knowledge gap. Methods We applied multilevel logistic modeling to 9,842 adults in 830 neighborhoods in Philadelphia to examine three hypotheses. Results First, the detrimental effect of discrimination on self-reported health was underestimated without considering neighborhood features as moderators. The estimated coefficient (β) increased from approximately 0.02 to 1.84 or higher. Second, the negative association between discrimination and self-reported health was enhanced when individuals with discrimination experience lived in neighborhoods with higher housing values (β= 0.42). Third, the adverse association of discrimination with self-reported health was attenuated when people reporting discrimination resided in neighborhoods marked by higher income inequality (β= −4.34) and higher concentrations of single parent households with children (β= −0.03) and minorities (β= −0.01). Conclusions We not only confirmed the moderating roles of neighborhood characteristics, but also suggested that the relative deprivation and social capital perspectives could be used to understand how perceived housing discrimination affects self-reported health via neighborhood factors. PMID:27306452

Social context matters: Ethnicity, discrimination and stress reactivity.

PubMed

Busse, David; Yim, Ilona S; Campos, Belinda

2017-09-01

Exposure to chronic discrimination is associated with increased morbidity and mortality. The study of biobehavioral pathways linking discrimination with health outcomes has mostly focused on the cardiovascular system, with fewer studies addressing the hypothalamus-pituitary-adrenal (HPA) axis. In this study we tested associations between Latino ethnicity, experiences of discrimination, and cortisol responses to an acute laboratory stressor. One hundred fifty eight individuals (92 female, 66 male) between the ages of 18 and 29 years participated in the study. Salivary cortisol was measured once before and eight times after administration of a laboratory stressor (the Trier Social Stress Test). Past experiences of discrimination were measured with the Experiences of Discrimination Scale. Findings from conditional process modeling suggest that Latino ethnicity predicted a) heightened cortisol reactivity and b) more pronounced cortisol recovery through discrimination experiences (mediator), and that this effect was further moderated by sex with a significant indirect effect only among males. The direct path from Latino ethnicity to cortisol reactivity or cortisol recovery was, however, not significant. In sum, findings suggest that Latino ethnicity and discrimination interact to predict cortisol dysregulation, which implies that an appropriate model for understanding minority health discrepancies must incorporate interactive processes and cannot simply rely on the effects of ethnicity or discrimination alone. Copyright © 2017 Elsevier Ltd. All rights reserved.

Selective Attention: A Comparative Study on Argentine Students from Different Socioeconomic Contexts

ERIC Educational Resources Information Center

Ison, Mirta S.; Greco, Carolina; Korzeniowski, Celina; Morelato, Gabriela

2015-01-01

Introduction: Attentional Efficiency (AE) is defined as the accuracy with which a child discriminates, from a group of similar stimuli, those which are identical to a model, within a certain time period. Various factors may be associated with a higher or lower AE, among which is socioeconomic context. The goals of this study were: 1) To describe…

Object/Context-Specific Memory Deficits Associated with Loss of Hippocampal Granule Cells after Adrenalectomy in Rats

ERIC Educational Resources Information Center

Spanswick, Simon C.; Sutherland, Robert J.

2010-01-01

Chronic adrenalectomy (ADX) causes a gradual and selective loss of granule cells in the dentate gyrus (DG) of the rat. Here, we administered replacement corticosterone to rats beginning 10 wk after ADX. We then tested them in three discrimination tasks based on object novelty, location, or object/context association. Only during testing of the…

Identification and discrimination of Spanish front vowels

NASA Astrophysics Data System (ADS)

Castellanos, Isabel; Lopez-Bascuas, Luis E.

2004-05-01

The idea that vowels are perceived less categorically than consonants is widely accepted. Ades [Psychol. Rev. 84, 524-530 (1977)] tried to explain this fact on the basis of the Durlach and Braida [J. Acoust. Soc. Am. 46, 372-383 (1969)] theory of intensity resolution. Since vowels seem to cover a broader perceptual range, context-coding noise for vowels should be greater than for consonants leading to a less categorical performance on the vocalic segments. However, relatively recent work by Macmillan et al. [J. Acoust. Soc. Am. 84, 1262-1280 (1988)] has cast doubt on the assumption of different perceptual ranges for vowels and consonants even though context variance is acknowledged to be greater for the former. A possibility is that context variance increases as number of long-term phonemic categories also increases. To test this hypothesis we focused on Spanish as the target language. Spanish has less vowel categories than English and the implication is that Spanish vowels will be more categorically perceived. Identification and discrimination experiments were conducted on a synthetic /i/-/e/ continuum and the obtained functions were studied to assess whether Spanish vowels are more categorically perceived than English vowels. The results are discussed in the context of different theories of speech perception.

Detection of Neuron Membranes in Electron Microscopy Images Using Multi-scale Context and Radon-Like Features

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

Seyedhosseini, Mojtaba; Kumar, Ritwik; Jurrus, Elizabeth R.

2011-10-01

Automated neural circuit reconstruction through electron microscopy (EM) images is a challenging problem. In this paper, we present a novel method that exploits multi-scale contextual information together with Radon-like features (RLF) to learn a series of discriminative models. The main idea is to build a framework which is capable of extracting information about cell membranes from a large contextual area of an EM image in a computationally efficient way. Toward this goal, we extract RLF that can be computed efficiently from the input image and generate a scale-space representation of the context images that are obtained at the output ofmore » each discriminative model in the series. Compared to a single-scale model, the use of a multi-scale representation of the context image gives the subsequent classifiers access to a larger contextual area in an effective way. Our strategy is general and independent of the classifier and has the potential to be used in any context based framework. We demonstrate that our method outperforms the state-of-the-art algorithms in detection of neuron membranes in EM images.« less

A solar cycle dependence of nonlinearity in magnetospheric activity

NASA Astrophysics Data System (ADS)

Johnson, Jay R.; Wing, Simon

2005-04-01

The nonlinear dependencies inherent to the historical Kp data stream (1932-2003) are examined using mutual information and cumulant-based cost as discriminating statistics. The discriminating statistics are compared with surrogate data streams that are constructed using the corrected amplitude adjustment Fourier transform (CAAFT) method and capture the linear properties of the original Kp data. Differences are regularly seen in the discriminating statistics a few years prior to solar minima, while no differences are apparent at the time of solar maxima. These results suggest that the dynamics of the magnetosphere tend to be more linear at solar maximum than at solar minimum. The strong nonlinear dependencies tend to peak on a timescale around 40-50 hours and are statistically significant up to 1 week. Because the solar wind driver variables, VBs, and dynamical pressure exhibit a much shorter decorrelation time for nonlinearities, the results seem to indicate that the nonlinearity is related to internal magnetospheric dynamics. Moreover, the timescales for the nonlinearity seem to be on the same order as that for storm/ring current relaxation. We suggest that the strong solar wind driving that occurs around solar maximum dominates the magnetospheric dynamics, suppressing the internal magnetospheric nonlinearity. On the other hand, in the descending phase of the solar cycle just prior to solar minimum, when magnetospheric activity is weaker, the dynamics exhibit a significant nonlinear internal magnetospheric response that may be related to increased solar wind speed.

Climatic Control on Plant and Soil δ13C along an Altitudinal Transect of Lushan Mountain in Subtropical China: Characteristics and Interpretation of Soil Carbon Dynamics

PubMed Central

Du, Baoming; Liu, Chunjiang; Kang, Hongzhang; Zhu, Penghua; Yin, Shan; Shen, Guangrong; Hou, Jingli; Ilvesniemi, Hannu

2014-01-01

Decreasing temperature and increasing precipitation along altitude gradients are typical mountain climate in subtropical China. In such a climate regime, identifying the patterns of the C stable isotope composition (δ13C) in plants and soils and their relations to the context of climate change is essential. In this study, the patterns of δ13C variation were investigated for tree leaves, litters, and soils in the natural secondary forests at four altitudes (219, 405, 780, and 1268 m a.s.l.) in Lushan Mountain, central subtropical China. For the dominant trees, both leaf and leaf-litter δ13C decreased as altitude increased from low to high altitude, whereas surface soil δ13C increased. The lower leaf δ13C at high altitudes was associated with the high moisture-related discrimination, while the high soil δ13C is attributed to the low temperature-induced decay. At each altitude, soil δ13C became enriched with soil depth. Soil δ13C increased with soil C concentrations and altitude, but decreased with soil depth. A negative relationship was also found between O-alkyl C and δ13C in litter and soil, whereas a positive relationship was observed between aromatic C and δ13C. Lower temperature and higher moisture at high altitudes are the predominant control factors of δ13C variation in plants and soils. These results help understand C dynamics in the context of global warming. PMID:24466099

The big sell: Managing stigma and workplace discrimination following moderate to severe brain injury.

PubMed

Stergiou-Kita, Mary; Grigorovich, Alisa; Damianakis, Thecla; Le Dorze, Guylaine; David, Christine; Lemsky, Carolyn; Hebert, Debbie

2017-01-01

Misperceptions regarding persons with brain injuries (PWBI) can lead to stigmatization, workplace discrimination and, in turn, influence PWBIs full vocational integration. In this study we explored how stigma may influence return-to-work processes, experiences of stigma and discrimination at the workplace for persons with (moderate to severe) brain injuries, and strategies that can be employed to manage disclosure. Exploratory qualitative study; used in-depth interviews and an inductive thematic analytical approach in data analysis. Ten PWBI and five employment service providers participated. PWBI discussed their work experiences, relationships with supervisors and co-workers and experiences of stigma and/or discrimination at work. Employment service providers discussed their perceptions regarding PWBI's rights and abilities to work, reported incidents of workplace discrimination, and how issues related to stigma, discrimination and disclosure are managed. Three themes were identified: i) public, employer and provider knowledge about brain injury and beliefs about PWBI; ii) incidents of workplace discrimination; iii) disclosure. Misperceptions regarding PWBI persist amongst the public and employers. Incidents of workplace discrimination included social exclusion at the workplace, hiring discrimination, denial of promotion/demotion, harassment, and failure to provide reasonable accommodations. Disclosure decisions required careful consideration of PWBI needs, the type of information that should be shared, and the context in which that information is shared. Public understanding about PWBI remains limited. PWBI require further assistance to manage disclosure and incidents of workplace discrimination.

Multifactorial discrimination as a fundamental cause of mental health inequities.

PubMed

Khan, Mariam; Ilcisin, Misja; Saxton, Katherine

2017-03-04

The theory of fundamental causes explains why health disparities persist over time, even as risk factors, mechanisms, and diseases change. Using an intersectional framework, we evaluated multifactorial discrimination as a fundamental cause of mental health disparities. Using baseline data from the Project STRIDE: Stress, Identity, and Mental Health study, we examined the health effects of discrimination among individuals who self-identified as lesbian, gay, or bisexual. We used logistic and linear regression to assess whether multifactorial discrimination met the four criteria designating a fundamental cause, namely that the cause: 1) influences multiple health outcomes, 2) affects multiple risk factors, 3) involves access to resources that can be leveraged to reduce consequences of disease, and 4) reproduces itself in varied contexts through changing mechanisms. Multifactorial discrimination predicted high depression scores, psychological well-being, and substance use disorder diagnosis. Discrimination was positively associated with risk factors for high depression scores: chronic strain and total number of stressful life events. Discrimination was associated with significantly lower levels of mastery and self-esteem, protective factors for depressive symptomatology. Even after controlling for risk factors, discrimination remained a significant predictor for high depression scores. Among subjects with low depression scores, multifactorial discrimination also predicted anxiety and aggregate mental health scores. Multifactorial discrimination should be considered a fundamental cause of mental health inequities and may be an important cause of broad health disparities among populations with intersecting social identities.

Evolutionary models of interstellar chemistry

NASA Technical Reports Server (NTRS)

Prasad, Sheo S.

1987-01-01

The goal of evolutionary models of interstellar chemistry is to understand how interstellar clouds came to be the way they are, how they will change with time, and to place them in an evolutionary sequence with other celestial objects such as stars. An improved Mark II version of an earlier model of chemistry in dynamically evolving clouds is presented. The Mark II model suggests that the conventional elemental C/O ratio less than one can explain the observed abundances of CI and the nondetection of O2 in dense clouds. Coupled chemical-dynamical models seem to have the potential to generate many observable discriminators of the evolutionary tracks. This is exciting, because, in general, purely dynamical models do not yield enough verifiable discriminators of the predicted tracks.

Acculturation Conflict Among Latino Youth: Discrimination, Ethnic Identity, and Depressive Symptoms

PubMed Central

Huq, Nadia; Stein, Gabriela L.; Gonzalez, Laura M.

2015-01-01

Objectives Patterns of parent-adolescent conflict differ between immigrant and nonimmigrant families living in the United States (Fuligni, 1998). Despite this, there is limited empirical literature examining the nuanced nature of parent-adolescent conflict in immigrant families. To fill this gap, the current study examined the role of two types of conflict (i.e., general and acculturation) in predicting psychosocial outcomes (i.e., depressive symptoms and ethnic identity) among Latino adolescents, and whether these relationships differ within the context of peer discrimination. Methods All survey administration was completed in the participating school’s cafeteria. The sample consisted of 7th–10th graders (n = 172) with a mean age of 14.01 years (SD = 1.32.) The sample consisted of 53% females, and was primarily Mexican in origin (78%). Results As hypothesized, parent-adolescent acculturation conflict uniquely predicted greater depressive symptoms and lower ethnic private regard, even when controlling for parent-adolescent general conflict. However, acculturation conflict predicted lower ethnic private regard only in the presence of greater peer discrimination. More specifically, peer discrimination moderated the relation between acculturation conflict and ethnic private regard such that adolescents who reported the highest levels of acculturation conflict and peer discrimination reported the lowest levels of ethnic private regard. Conclusions These results suggest that for Latino youth and their families, acculturation conflict may be particularly problematic, as compared to general conflict. In addition, youth who face ethnicity-based stressors in both familial and school contexts are especially at risk in their ethnic identity development. PMID:26460666

Acculturation conflict among Latino youth: Discrimination, ethnic identity, and depressive symptoms.

PubMed

Huq, Nadia; Stein, Gabriela L; Gonzalez, Laura M

2016-07-01

Patterns of parent-adolescent conflict differ between immigrant and nonimmigrant families living in the United States (Fuligni, 1998). Despite this, there is limited empirical literature examining the nuanced nature of parent-adolescent conflict in immigrant families. To fill this gap, the current study examined the role of 2 types of conflict (i.e., general and acculturation) in predicting psychosocial outcomes (i.e., depressive symptoms and ethnic identity) among Latino adolescents, and whether these relationships differ within the context of peer discrimination. All survey administration was completed in the participating school's cafeteria. The sample consisted of 7th through 10th graders (n = 172) with a mean age of 14.01 years (SD = 1.32.) The sample consisted of 53% females, and was primarily Mexican in origin (78%). As hypothesized, parent-adolescent acculturation conflict uniquely predicted greater depressive symptoms and lower ethnic private regard, even when controlling for parent-adolescent general conflict. However, acculturation conflict predicted lower ethnic private regard only in the presence of greater peer discrimination. More specifically, peer discrimination moderated the relation between acculturation conflict and ethnic private regard such that adolescents who reported the highest levels of acculturation conflict and peer discrimination reported the lowest levels of ethnic private regard. These results suggest that for Latino youth and their families, acculturation conflict may be particularly problematic, as compared with general conflict. In addition, youth who face ethnicity-based stressors in both familial and school contexts are especially at risk in their ethnic identity development. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Value-based differential pricing: efficient prices for drugs in a global context.

PubMed

Danzon, Patricia; Towse, Adrian; Mestre-Ferrandiz, Jorge

2015-03-01

This paper analyzes pharmaceutical pricing between and within countries to achieve second-best static and dynamic efficiency. We distinguish countries with and without universal insurance, because insurance undermines patients' price sensitivity, potentially leading to prices above second-best efficient levels. In countries with universal insurance, if each payer unilaterally sets an incremental cost-effectiveness ratio (ICER) threshold based on its citizens' willingness-to-pay for health; manufacturers price to that ICER threshold; and payers limit reimbursement to patients for whom a drug is cost-effective at that price and ICER, then the resulting price levels and use within each country and price differentials across countries are roughly consistent with second-best static and dynamic efficiency. These value-based prices are expected to differ cross-nationally with per capita income and be broadly consistent with Ramsey optimal prices. Countries without comprehensive insurance avoid its distorting effects on prices but also lack financial protection and affordability for the poor. Improving pricing efficiency in these self-pay countries includes improving regulation and consumer information about product quality and enabling firms to price discriminate within and between countries. © 2013 The Authors. Health Economics published by John Wiley & Sons Ltd.

Auditory responses in the amygdala to social vocalizations

NASA Astrophysics Data System (ADS)

Gadziola, Marie A.

The underlying goal of this dissertation is to understand how the amygdala, a brain region involved in establishing the emotional significance of sensory input, contributes to the processing of complex sounds. The general hypothesis is that communication calls of big brown bats (Eptesicus fuscus) transmit relevant information about social context that is reflected in the activity of amygdalar neurons. The first specific aim analyzed social vocalizations emitted under a variety of behavioral contexts, and related vocalizations to an objective measure of internal physiological state by monitoring the heart rate of vocalizing bats. These experiments revealed a complex acoustic communication system among big brown bats in which acoustic cues and call structure signal the emotional state of a sender. The second specific aim characterized the responsiveness of single neurons in the basolateral amygdala to a range of social syllables. Neurons typically respond to the majority of tested syllables, but effectively discriminate among vocalizations by varying the response duration. This novel coding strategy underscores the importance of persistent firing in the general functioning of the amygdala. The third specific aim examined the influence of acoustic context by characterizing both the behavioral and neurophysiological responses to natural vocal sequences. Vocal sequences differentially modify the internal affective state of a listening bat, with lower aggression vocalizations evoking the greatest change in heart rate. Amygdalar neurons employ two different coding strategies: low background neurons respond selectively to very few stimuli, whereas high background neurons respond broadly to stimuli but demonstrate variation in response magnitude and timing. Neurons appear to discriminate the valence of stimuli, with aggression sequences evoking robust population-level responses across all sound levels. Further, vocal sequences show improved discrimination among stimuli compared to isolated syllables, and this improved discrimination is expressed in part by the timing of action potentials. Taken together, these data support the hypothesis that big brown bat social vocalizations transmit relevant information about the social context that is encoded within the discharge pattern of amygdalar neurons ultimately responsible for coordinating appropriate social behaviors. I further propose that vocalization-evoked amygdalar activity will have significant impact on subsequent sensory processing and plasticity.

The Anterior Thalamus is Critical for Overcoming Interference in a Context-Dependent Odor Discrimination Task

PubMed Central

Law, L. Matthew; Smith, David M.

2012-01-01

The anterior thalamus (AT) is anatomically interconnected with the hippocampus and other structures known to be involved in memory, and the AT is involved in many of the same learning and memory functions as the hippocampus. For example, like the hippocampus, the AT is involved in spatial cognition and episodic memory. The hippocampus also has a well-documented role in contextual memory processes, but it is not known whether the AT is similarly involved in contextual memory. In the present study, we assessed the role of the AT in contextual memory processes by temporarily inactivating the AT and training rats on a recently developed context-based olfactory list learning task, which was designed to assess the use of contextual information to resolve interference. Rats were trained on one list of odor discrimination problems, followed by training on a second list in either the same context or a different context. In order to induce interference, some of the odors appeared on both lists with their predictive value reversed. Control rats that learned the two lists in different contexts performed significantly better than rats that learned the two lists in the same context. However, AT lesions completely abolished this contextual learning advantage, a result that is very similar to the effects of hippocampal inactivation. These findings demonstrate that the AT, like the hippocampus, is involved in contextual memory and suggest that the hippocampus and AT are part of a functional circuit involved in contextual memory. PMID:23025833

Stigma, discrimination and HIV outcomes among people living with HIV in Rio de Janeiro, Brazil: The intersection of multiple social inequalities.

PubMed

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.

Ethnic identity, racial discrimination and attenuated psychotic symptoms in an urban population of emerging adults.

PubMed

Anglin, Deidre M; Lui, Florence; Espinosa, Adriana; Tikhonov, Aleksandr; Ellman, Lauren

2018-06-01

Studies suggest strong ethnic identity generally protects against negative mental health outcomes associated with racial discrimination. In light of evidence suggesting racial discrimination may enhance psychosis risk in racial and ethnic minority (REM) populations, the present study explored the relationship between ethnic identity and attenuated positive psychotic symptoms (APPS) and whether ethnic identity moderates the association between racial discrimination and these symptoms. A sample of 644 non-help-seeking REM emerging adults was administered self-report inventories for psychosis risk, experiences of discrimination and ethnic identity. Latent class analysis was applied to determine the nature and number of ethnic identity types in this population. The direct association between ethnic identity and APPS and the interaction between ethnic identity and racial discrimination on APPS were determined in linear regression analyses. Results indicated three ethnic identity classes (very low, moderate to high and very high). Ethnic identity was not directly related to APPS; however, it was related to APPS under racially discriminating conditions. Specifically, participants who experienced discrimination in the moderate to high or very high ethnic identity classes reported fewer symptoms than participants who experienced discrimination in the very low ethnic identity class. Strong ethnic group affiliation and connection may serve a protective function for psychosis risk in racially discriminating environments and contexts among REM young adults. The possible social benefits of strong ethnic identification among REM youth who face racial discrimination should be explored further in clinical high-risk studies. © 2016 John Wiley & Sons Australia, Ltd.

Aging and the discrimination of 3-D shape from motion and binocular disparity.

PubMed

Norman, J Farley; Holmin, Jessica S; Beers, Amanda M; Cheeseman, Jacob R; Ronning, Cecilia; Stethen, Angela G; Frost, Adam L

2012-10-01

Two experiments evaluated the ability of younger and older adults to visually discriminate 3-D shape as a function of surface coherence. The coherence was manipulated by embedding the 3-D surfaces in volumetric noise (e.g., for a 55 % coherent surface, 55 % of the stimulus points fell on a 3-D surface, while 45 % of the points occupied random locations within the same volume of space). The 3-D surfaces were defined by static binocular disparity, dynamic binocular disparity, and motion. The results of both experiments demonstrated significant effects of age: Older adults required more coherence (tolerated volumetric noise less) for reliable shape discrimination than did younger adults. Motion-defined and static-binocular-disparity-defined surfaces resulted in similar coherence thresholds. However, performance for dynamic-binocular-disparity-defined surfaces was superior (i.e., the observers' surface coherence thresholds were lowest for these stimuli). The results of both experiments showed that younger and older adults possess considerable tolerance to the disrupting effects of volumetric noise; the observers could reliably discriminate 3-D surface shape even when 45 % of the stimulus points (or more) constituted noise.

Respective Role of the Dorsal Hippocampus and the Entorhinal Cortex during the Recombination of Previously Learned Olfactory-Tactile Associations in the Rat

ERIC Educational Resources Information Center

Boisselier, Lise; Ferry, Barbara; Gervais, Rémi

2017-01-01

The hippocampal formation has been extensively described as a key component for object recognition in conjunction with place and context. The present study aimed at describing neural mechanisms in the hippocampal formation that support olfactory-tactile (OT) object discrimination in a task where space and context were not taken into account. The…

Anti-dynamic-crosstalk method for single photon LIDAR detection

NASA Astrophysics Data System (ADS)

Zhang, Fan; Liu, Qiang; Gong, Mali; Fu, Xing

2017-11-01

With increasing number of vehicles equipped with light detection and ranging (LIDAR), crosstalk is identified as a critical and urgent issue in the range detection for active collision avoidance. Chaotic pulse position modulation (CPPM) applied in the transmitting pulse train has been shown to prevent crosstalk as well as range ambiguity. However, static and unified strategy on discrimination threshold and the number of accumulated pulse is not valid against crosstalk with varying number of sources and varying intensity of each source. This paper presents an adaptive algorithm to distinguish the target echo from crosstalk with dynamic and unknown level of intensity in the context of intelligent vehicles. New strategy is given based on receiver operating characteristics (ROC) curves that consider the detection requirements of the probability of detection and false alarm for the scenario with varying crosstalk. In the adaptive algorithm, the detected results are compared by the new strategy with both the number of accumulated pulses and the threshold being raised step by step, so that the target echo can be exactly identified from crosstalk with the dynamic and unknown level of intensity. The validity of the algorithm has been verified through the experiments with a single photon detector and the time correlated single photo counting (TCSPC) technique, demonstrating a marked drop in required shots for identifying the target compared with static and unified strategy

Differential effects of visual context on pattern discrimination by pigeons (Columba livia) and humans (Homo sapiens).

PubMed

Kelly, Debbie M; Cook, Robert G

2003-06-01

Three experiment examined the role of contextual information during line orientation and line position discriminations by pigeons (Columba livia) and humans (Homo sapiens). Experiment 1 tested pigeons' performance with these stimuli in a target localization task using texture displays. Experiments 2 and 3 tested pigeons and humans, respectively, with small and large variations of these stimuli in a same-different task. Humans showed a configural superiority effect when tested with displays constructed from large elements but not when tested with the smaller, more densely packed texture displays. The pigeons, in contrast, exhibited a configural inferiority effect when required to discriminate line orientation, regardless of stimulus size. These contrasting results suggest a species difference in the perceptionand use of features and contextual information in the discrimination of line information.

The time-course of activation in the dorsal and ventral visual streams during landmark cueing and perceptual discrimination tasks.

PubMed

Lambert, Anthony J; Wootton, Adrienne

2017-08-01

Different patterns of high density EEG activity were elicited by the same peripheral stimuli, in the context of Landmark Cueing and Perceptual Discrimination tasks. The C1 component of the visual event-related potential (ERP) at parietal - occipital electrode sites was larger in the Landmark Cueing task, and source localisation suggested greater activation in the superior parietal lobule (SPL) in this task, compared to the Perceptual Discrimination task, indicating stronger early recruitment of the dorsal visual stream. In the Perceptual Discrimination task, source localisation suggested widespread activation of the inferior temporal gyrus (ITG) and fusiform gyrus (FFG), structures associated with the ventral visual stream, during the early phase of the P1 ERP component. Moreover, during a later epoch (171-270ms after stimulus onset) increased temporal-occipital negativity, and stronger recruitment of ITG and FFG were observed in the Perceptual Discrimination task. These findings illuminate the contrasting functions of the dorsal and ventral visual streams, to support rapid shifts of attention in response to contextual landmarks, and conscious discrimination, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

The meaning of workplace discrimination for women with disabilities.

PubMed

Smith Randolph, Diane

2005-01-01

Studies have found that persons with disabilities who are also members of other minority groups or women encounter dual discrimination. This paper describes how women with disabilities who are in the workplace experience discrimination. In order to determine whether discrimination was a viable issue, theoretical contexts of feminist theory, disability theory, and attribution theory were examined as well as literature examining employment of women with disabilities. For this study, three women with various disabilities were interviewed regarding the effect of their disability on their typical workday, their employment and job seeking history, and employment opportunities. Qualitative data were also provided through mapping by the participants and pictorial data of worksites. Data were grouped into themes of pre-conceived notions of others, attitudes of others, accommodation issues, inclusion issues and exploitation issues. From these themes definitions of discrimination, nondiscrimination in the workplace were developed. Conclusions include the need for more research on workplace experiences of other or more specific populations that experience discrimination as well as the need for ethical reflection on the part of the researcher regarding vulnerable populations.

Perceived Discrimination and Its Association With Psychological Distress Among Newly Arrived Immigrants Before and After September 11, 2001

PubMed Central

Hassan, Ghayda; Moreau, Nicolas; Thombs, Brett D.

2011-01-01

Objectives. We compared the evolution of perception of discrimination from 1998 to 2007 among recent Arab (Muslim and non-Muslim) and Haitian immigrants to Montreal; we also studied the association between perception of discrimination and psychological distress in 1998 and 2007. Methods. We conducted this cross-sectional comparative research with 2 samples: one recruited in 1998 (n = 784) and the other in 2007 (n = 432). The samples were randomly extracted from the registry of the Ministry of Immigration and Cultural Communities of Quebec. Psychological distress was measured with the Hopkins Symptom Checklist-25. Results. The perception of discrimination increased from 1998 to 2007 among the Arab Muslim, Arab non-Muslim, and Haitian groups. Muslim Arabs experienced a significant increase in psychological distress associated with discrimination from 1998 to 2007. Conclusions. These results confirm an increase in perception of discrimination and psychological distress among Arab Muslim recent immigrant communities after September 11, 2001, and highlight the importance this context may have for other immigrant groups. PMID:20724695

Context-Dependent Modulation of Functional Connectivity: Secondary Somatosensory Cortex to Prefrontal Cortex Connections in Two-Stimulus-Interval Discrimination Tasks

PubMed Central

Chow, Stephanie S.; Romo, Ranulfo; Brody, Carlos D.

2010-01-01

In a complex world, a sensory cue may prompt different actions in different contexts. A laboratory example of context-dependent sensory processing is the two-stimulus-interval discrimination task. In each trial, a first stimulus (f1) must be stored in short-term memory and later compared with a second stimulus (f2), for the animal to come to a binary decision. Prefrontal cortex (PFC) neurons need to interpret the f1 information in one way (perhaps with a positive weight) and the f2 information in an opposite way (perhaps with a negative weight), although they come from the very same secondary somatosensory cortex (S2) neurons; therefore, a functional sign inversion is required. This task thus provides a clear example of context-dependent processing. Here we develop a biologically plausible model of a context-dependent signal transformation of the stimulus encoding from S2 to PFC. To ground our model in experimental neurophysiology, we use neurophysiological data recorded by R. Romo’s laboratory from both cortical area S2 and PFC in monkeys performing the task. Our main goal is to use experimentally observed context-dependent modulations of firing rates in cortical area S2 as the basis for a model that achieves a context-dependent inversion of the sign of S2 to PFC connections. This is done without requiring any changes in connectivity (Salinas, 2004b). We (1) characterize the experimentally observed context-dependent firing rate modulation in area S2, (2) construct a model that results in the sign transformation, and (3) characterize the robustness and consequent biological plausibility of the model. PMID:19494146

The Temporal Dynamics of Visual Search: Evidence for Parallel Processing in Feature and Conjunction Searches

PubMed Central

McElree, Brian; Carrasco, Marisa

2012-01-01

Feature and conjunction searches have been argued to delineate parallel and serial operations in visual processing. The authors evaluated this claim by examining the temporal dynamics of the detection of features and conjunctions. The 1st experiment used a reaction time (RT) task to replicate standard mean RT patterns and to examine the shapes of the RT distributions. The 2nd experiment used the response-signal speed–accuracy trade-off (SAT) procedure to measure discrimination (asymptotic detection accuracy) and detection speed (processing dynamics). Set size affected discrimination in both feature and conjunction searches but affected detection speed only in the latter. Fits of models to the SAT data that included a serial component overpredicted the magnitude of the observed dynamics differences. The authors concluded that both features and conjunctions are detected in parallel. Implications for the role of attention in visual processing are discussed. PMID:10641310

Object-based attention modulates the discrimination of level increments in stop-consonant noise bursts

PubMed Central

2018-01-01

This study tested the hypothesis that object-based attention modulates the discrimination of level increments in stop-consonant noise bursts. With consonant-vowel-consonant (CvC) words consisting of an ≈80-dB vowel (v), a pre-vocalic (Cv) and a post-vocalic (vC) stop-consonant noise burst (≈60-dB SPL), we measured discrimination thresholds (LDTs) for level increments (ΔL) in the noise bursts presented either in CvC context or in isolation. In the 2-interval 2-alternative forced-choice task, each observation interval presented a CvC word (e.g., /pæk/ /pæk/), and normal-hearing participants had to discern ΔL in the Cv or vC burst. Based on the linguistic word labels, the auditory events of each trial were perceived as two auditory objects (Cv-v-vC and Cv-v-vC) that group together the bursts and vowels, hindering selective attention to ΔL. To discern ΔL in Cv or vC, the events must be reorganized into three auditory objects: the to-be-attended pre-vocalic (Cv–Cv) or post-vocalic burst pair (vC–vC), and the to-be-ignored vowel pair (v–v). Our results suggest that instead of being automatic this reorganization requires training, in spite of using familiar CvC words. Relative to bursts in isolation, bursts in context always produced inferior ΔL discrimination accuracy (a context effect), which depended strongly on the acoustic separation between the bursts and the vowel, being much keener for the object apart from (post-vocalic) than for the object adjoining (pre-vocalic) the vowel (a temporal-position effect). Variability in CvC dimensions that did not alter the noise-burst perceptual grouping had minor effects on discrimination accuracy. In addition to being robust and persistent, these effects are relatively general, evincing in forced-choice tasks with one or two observation intervals, with or without variability in the temporal position of ΔL, and with either fixed or roving CvC standards. The results lend support to the hypothesis. PMID:29364931

Dynamic context discrimination : psychological evidence for the Sandia Cognitive Framework.

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

Speed, Ann Elizabeth

Human behavior is a function of an iterative interaction between the stimulus environment and past experience. It is not simply a matter of the current stimulus environment activating the appropriate experience or rule from memory (e.g., if it is dark and I hear a strange noise outside, then I turn on the outside lights and investigate). Rather, it is a dynamic process that takes into account not only things one would generally do in a given situation, but things that have recently become known (e.g., there have recently been coyotes seen in the area and one is known to bemore » rabid), as well as other immediate environmental characteristics (e.g., it is snowing outside, I know my dog is outside, I know the police are already outside, etc.). All of these factors combine to inform me of the most appropriate behavior for the situation. If it were the case that humans had a rule for every possible contingency, the amount of storage that would be required to enable us to fluidly deal with most situations we encounter would rapidly become biologically untenable. We can all deal with contingencies like the one above with fairly little effort, but if it isn't based on rules, what is it based on? The assertion of the Cognitive Systems program at Sandia for the past 5 years is that at the heart of this ability to effectively navigate the world is an ability to discriminate between different contexts (i.e., Dynamic Context Discrimination, or DCD). While this assertion in and of itself might not seem earthshaking, it is compelling that this ability and its components show up in a wide variety of paradigms across different subdisciplines in psychology. We begin by outlining, at a high functional level, the basic ideas of DCD. We then provide evidence from several different literatures and paradigms that support our assertion that DCD is a core aspect of cognitive functioning. Finally, we discuss DCD and the computational model that we have developed as an instantiation of DCD in more detail. Before commencing with our overview of DCD, we should note that DCD is not necessarily a theory in the classic sense. Rather, it is a description of cognitive functioning that seeks to unify highly similar findings across a wide variety of literatures. Further, we believe that such convergence warrants a central place in efforts to computationally emulate human cognition. That is, DCD is a general principle of cognition. It is also important to note that while we are drawing parallels across many literatures, these are functional parallels and are not necessarily structural ones. That is, we are not saying that the same neural pathways are involved in these phenomena. We are only saying that the different neural pathways that are responsible for the appearance of these various phenomena follow the same functional rules - the mechanisms are the same even if the physical parts are distinct. Furthermore, DCD is not a causal mechanism - it is an emergent property of the way the brain is constructed. DCD is the result of neurophysiology (cf. John, 2002, 2003). Finally, it is important to note that we are not proposing a generic learning mechanism such that one biological algorithm can account for all situation interpretation. Rather, we are pointing out that there are strikingly similar empirical results across a wide variety of disciplines that can be understood, in part, by similar cognitive processes. It is entirely possible, even assumed in some cases (i.e., primary language acquisition) that these more generic cognitive processes are complemented and constrained by various limits which may or may not be biological in nature (cf. Bates & Elman, 1996; Elman, in press).« less

Association of discrimination-related trauma with sexual risk among HIV-positive African American men who have sex with men.

PubMed

Fields, Errol L; Bogart, Laura M; Galvan, Frank H; Wagner, Glenn J; Klein, David J; Schuster, Mark A

2013-05-01

We investigated whether 1 form of traumatic stress, discrimination-related trauma (e.g., physical assault because of race), was associated with unprotected anal intercourse, especially when compared with non-discrimination-related trauma, among African American men who have sex with men. A convenience sample of 131 HIV-positive African American men who have sex with men receiving antiretroviral treatment completed audio computer-assisted self-interviews that covered unprotected anal intercourse, interpersonal trauma, and whether trauma was because of discrimination on the basis of race/ethnicity, HIV serostatus, or sexual orientation. Sixty percent reported at least 1 interpersonal trauma; they attributed at least 1 trauma to being gay (47%), African American (17%), or HIV positive (9%). In a multivariate regression, experiencing discrimination-related trauma was significantly associated with unprotected anal intercourse (adjusted odds ratio [AOR] = 2.4; 95% confidence interval [CI] = 1.0, 5.7; P = .04), whereas experiencing non-discrimination-related trauma was not (AOR = 1.3; 95% CI = 0.6, 3.1; P = .53). HIV-positive African American men who have sex with men experience high levels of discrimination-related trauma, a stressor associated with greater risk taking. HIV prevention interventions should consider the potential damaging effects of discrimination in the context of trauma.

Shape discrimination and concept formation in the jungle crow (Corvus macrorhynchos).

PubMed

Bogale, Bezawork Afework; Sugita, Shoei

2014-01-01

We investigated whether jungle crows can learn concepts by using printouts of shapes in a simultaneous two-alternative task. Jungle crows were first trained with a red triangle and red square until they reached the discrimination criterion (80% of correct choices in two blocks of 10 trials each). Then, we tested crows with successive transfer tests to investigate both the discrimination cues being used and concept formation ability, by using novel triangular and non-triangular stimuli. All of the jungle crows learnt to discriminate between the triangle and square during training. The discrimination performance was generally not affected either by changes in the colour of the stimuli or when both shape and colour cues conflicted, with the previously non-rewarded shape but matching colour (red square) versus rewarded shape but non-matching colour (green triangle). The use of only outlines of the familiar stimuli also did not affect discrimination behaviour of crows. In addition, crows significantly discriminated novel triangular shapes during the limited trials given, suggesting their ability to form the concept of triangularity. However, failure to discriminate when the novel stimuli size deviated from the original suggests that there is a limit to shape concept formation in a familiar-novel context in the jungle crow.

Exploring Discrimination and Mental Health Disparities Faced By Black Sexual Minority Women Using a Minority Stress Framework.

PubMed

Calabrese, Sarah K; Meyer, Ilan H; Overstreet, Nicole M; Haile, Rahwa; Hansen, Nathan B

2015-09-01

Black sexual minority women are triply marginalized due to their race, gender, and sexual orientation. We compared three dimensions of discrimination-frequency (regularity of occurrences), scope (number of types of discriminatory acts experienced), and number of bases (number of social statuses to which discrimination was attributed)-and self-reported mental health (depressive symptoms, psychological well-being, and social well-being) between 64 Black sexual minority women and each of two groups sharing two of three marginalized statuses: (a) 67 White sexual minority women and (b) 67 Black sexual minority men. Black sexual minority women reported greater discrimination frequency, scope, and number of bases and poorer psychological and social well-being than White sexual minority women and more discrimination bases, a higher level of depressive symptoms, and poorer social well-being than Black sexual minority men. We then tested and contrasted dimensions of discrimination as mediators between social status (race or gender) and mental health outcomes. Discrimination frequency and scope mediated the association between race and mental health, with a stronger effect via frequency among sexual minority women. Number of discrimination bases mediated the association between gender and mental health among Black sexual minorities. Future research and clinical practice would benefit from considering Black sexual minority women's mental health in a multidimensional minority stress context.

Adult Age Differences in Production and Monitoring in Dual-List Free Recall

PubMed Central

Wahlheim, Christopher N.; Ball, B. Hunter; Richmond, Lauren L.

2017-01-01

The present experiment examined adult age differences in the production and monitoring of responses in dual-list free recall. Younger and older adults studied two lists of unrelated words and were instructed to recall from List 1, List 2, or List 1 and List 2. An externalized free recall (EFR) procedure required participants to: 1) report all responses that came to mind while recalling from specific lists, 2) classify responses as correct or incorrect, and 3) provide confidence judgments for their accuracy classifications. Relative to younger adults, older adults showed a monitoring deficit by misclassifying proportionally more responses and discriminating more poorly between correct and incorrect responses in their confidence judgments. This deficit was especially pronounced under conditions of retroactive interference that occurred when participants recalled from List 1 only. A comparison of retrieval dynamics for all responses produced and for those that participants were reasonably confident were correct provided information about age differences in preretrieval context reinstatement and postretrieval monitoring of retrieved context. One noteworthy finding was that total production when recalling from List 1 showed that List 2 responses remained more accessible across the first several retrieval attempts for older than younger adults, which indicated a substantial age difference in the ability to reinstate List 1 context. Overall, the present findings provide a nuanced characterization of age differences in the operation of production and monitoring mechanisms under conditions of proactive and retroactive interference that can inform models of free recall. PMID:28206784

Adult age differences in production and monitoring in dual-list free recall.

PubMed

Wahlheim, Christopher N; Ball, B Hunter; Richmond, Lauren L

2017-06-01

The present experiment examined adult age differences in the production and monitoring of responses in dual-list free recall. Younger and older adults studied 2 lists of unrelated words and were instructed to recall from List 1, List 2, or List 1 and List 2. An externalized free recall procedure required participants to: (a) report all responses that came to mind while recalling from specific lists, (b) classify responses as correct or incorrect, and (c) provide confidence judgments for their accuracy classifications. Relative to younger adults, older adults showed a monitoring deficit by misclassifying proportionally more responses and discriminating more poorly between correct and incorrect responses in their confidence judgments. This deficit was especially pronounced under conditions of retroactive interference that occurred when participants recalled from List 1 only. A comparison of retrieval dynamics for all responses produced and for those that participants were reasonably confident were correct provided information about age differences in preretrieval context reinstatement and postretrieval monitoring of retrieved context. One noteworthy finding was that total production when recalling from List 1 showed that List 2 responses remained more accessible across the first several retrieval attempts for older than younger adults, which indicated a substantial age difference in the ability to reinstate List 1 context. Overall, the present findings provide a nuanced characterization of age differences in the operation of production and monitoring mechanisms under conditions of proactive and retroactive interference that can inform models of free recall. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Recognition of platinum-DNA adducts by HMGB1a.

PubMed

Ramachandran, Srinivas; Temple, Brenda; Alexandrova, Anastassia N; Chaney, Stephen G; Dokholyan, Nikolay V

2012-09-25

Cisplatin (CP) and oxaliplatin (OX), platinum-based drugs used widely in chemotherapy, form adducts on intrastrand guanines (5'GG) in genomic DNA. DNA damage recognition proteins, transcription factors, mismatch repair proteins, and DNA polymerases discriminate between CP- and OX-GG DNA adducts, which could partly account for differences in the efficacy, toxicity, and mutagenicity of CP and OX. In addition, differential recognition of CP- and OX-GG adducts is highly dependent on the sequence context of the Pt-GG adduct. In particular, DNA binding protein domain HMGB1a binds to CP-GG DNA adducts with up to 53-fold greater affinity than to OX-GG adducts in the TGGA sequence context but shows much smaller differences in binding in the AGGC or TGGT sequence contexts. Here, simulations of the HMGB1a-Pt-DNA complex in the three sequence contexts revealed a higher number of interface contacts for the CP-DNA complex in the TGGA sequence context than in the OX-DNA complex. However, the number of interface contacts was similar in the TGGT and AGGC sequence contexts. The higher number of interface contacts in the CP-TGGA sequence context corresponded to a larger roll of the Pt-GG base pair step. Furthermore, geometric analysis of stacking of phenylalanine 37 in HMGB1a (Phe37) with the platinated guanines revealed more favorable stacking modes correlated with a larger roll of the Pt-GG base pair step in the TGGA sequence context. These data are consistent with our previous molecular dynamics simulations showing that the CP-TGGA complex was able to sample larger roll angles than the OX-TGGA complex or either CP- or OX-DNA complexes in the AGGC or TGGT sequences. We infer that the high binding affinity of HMGB1a for CP-TGGA is due to the greater flexibility of CP-TGGA compared to OX-TGGA and other Pt-DNA adducts. This increased flexibility is reflected in the ability of CP-TGGA to sample larger roll angles, which allows for a higher number of interface contacts between the Pt-DNA adduct and HMGB1a.

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

PubMed

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

2010-01-01

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

Racial and Gender Discrimination in the Stress Process: Implications for African American Women's Health and Well-Being

PubMed Central

Perry, Brea L.; Harp, Kathi L. H.; Oser, Carrie B.

2013-01-01

In recent decades, sociologists have increasingly adopted an intersectionality framework to explore and explain the complex and interconnected nature of inequalities in the areas of race, class, and gender. Using an inclusion-centered approach and a sample of 204 low-socioeconomic-status (SES) African American women, the authors theorize and explore the role of racial and gender discrimination in the stress process. Analyses examine relationships between social stressors (racial and gender discrimination) and individual stressors occurring in each of six distinct social contexts. Furthermore, the authors evaluate the effects of racial and gender discrimination as compared to individual stressors on three indicators of mental health and well-being. Findings suggest that racial and gender discrimination increases risk for poor health and low well-being, working both directly and indirectly through increased vulnerability to individual stressors. This research demonstrates the value of a more comprehensive study of stressors that influence the health of low-SES African American women and other multiply disadvantaged groups. PMID:24077024

Beliefs, stigma and discrimination associated with mental health problems in Uganda: implications for theory and practice.

PubMed

Quinn, Neil; Knifton, Lee

2014-09-01

There are major gaps in knowledge about beliefs, stigma and discrimination in Uganda, including the relationship between different cultural beliefs and stigmatising responses, how stigma and beliefs result in discrimination and the impact of social factors such as gender, poverty and ethnic conflict. This exploratory study aims to understand beliefs, stigma and discrimination associated with mental health in Uganda in more depth from the perspectives of different stakeholders. Focus groups and interviews were undertaken with mental health activists, policymakers, practitioners, non-governmental and human rights organisations, journalists and academics. Stigma was reported by individuals, families, communities and institutions, including health services. The study also found stigmatising beliefs linked to traditional, religious and medical explanatory frameworks, high levels of 'associated stigma', common mental health problems rarely medicalised and discrimination linked to poverty, gender and conflict. The findings suggest the need to address stigma in their cultural and social context, alongside other human rights initiatives. © The Author(s) 2013.

Racial and Gender Discrimination in the Stress Process: Implications for African American Women's Health and Well-Being.

PubMed

Perry, Brea L; Harp, Kathi L H; Oser, Carrie B

2013-01-01

In recent decades, sociologists have increasingly adopted an intersectionality framework to explore and explain the complex and interconnected nature of inequalities in the areas of race, class, and gender. Using an inclusion-centered approach and a sample of 204 low-socioeconomic-status (SES) African American women, the authors theorize and explore the role of racial and gender discrimination in the stress process. Analyses examine relationships between social stressors (racial and gender discrimination) and individual stressors occurring in each of six distinct social contexts. Furthermore, the authors evaluate the effects of racial and gender discrimination as compared to individual stressors on three indicators of mental health and well-being. Findings suggest that racial and gender discrimination increases risk for poor health and low well-being, working both directly and indirectly through increased vulnerability to individual stressors. This research demonstrates the value of a more comprehensive study of stressors that influence the health of low-SES African American women and other multiply disadvantaged groups.

Unravelling fears of genetic discrimination: an exploratory study of Dutch HCM families in an era of genetic non-discrimination acts.

PubMed

Geelen, Els; Horstman, Klasien; Marcelis, Carlo L M; Doevendans, Pieter A; Van Hoyweghen, Ine

2012-10-01

Since the 1990s, many countries in Europe and the United States have enacted genetic non-discrimination legislation to prevent people from deferring genetic tests for fear that insurers or employers would discriminate against them based on that information. Although evidence for genetic discrimination exists, little is known about the origins and backgrounds of fears of discrimination and how it affects decisions for uptake of genetic testing. The aim of this article is to gain a better understanding of these fears and its possible impact on the uptake of testing by studying the case of hypertrophic cardiomyopathy (HCM). In a qualitative study, we followed six Dutch extended families involved in genetic testing for HCM for three-and-a-half years. Semi-structured interviews were conducted with 57 members of these families. Based on the narratives of the families, we suggest that fears of discrimination have to be situated in the broader social and life-course context of family and kin. We describe the processes in which families developed meaningful interpretations of genetic discrimination and how these interpretations affected family members' decisions to undergo genetic testing. Our findings show that fears of genetic discrimination do not so much stem from the opportunity of genetic testing but much more from earlier experiences of discrimination of diseased family members. These results help identify the possible limitations of genetic non-discrimination regulations and provide direction to clinicians supporting their clients as they confront issues of genetic testing and genetic discrimination.

Unravelling fears of genetic discrimination: an exploratory study of Dutch HCM families in an era of genetic non-discrimination acts

PubMed Central

Geelen, Els; Horstman, Klasien; Marcelis, Carlo LM; Doevendans, Pieter A; Van Hoyweghen, Ine

2012-01-01

Since the 1990s, many countries in Europe and the United States have enacted genetic non-discrimination legislation to prevent people from deferring genetic tests for fear that insurers or employers would discriminate against them based on that information. Although evidence for genetic discrimination exists, little is known about the origins and backgrounds of fears of discrimination and how it affects decisions for uptake of genetic testing. The aim of this article is to gain a better understanding of these fears and its possible impact on the uptake of testing by studying the case of hypertrophic cardiomyopathy (HCM). In a qualitative study, we followed six Dutch extended families involved in genetic testing for HCM for three-and-a-half years. Semi-structured interviews were conducted with 57 members of these families. Based on the narratives of the families, we suggest that fears of discrimination have to be situated in the broader social and life-course context of family and kin. We describe the processes in which families developed meaningful interpretations of genetic discrimination and how these interpretations affected family members' decisions to undergo genetic testing. Our findings show that fears of genetic discrimination do not so much stem from the opportunity of genetic testing but much more from earlier experiences of discrimination of diseased family members. These results help identify the possible limitations of genetic non-discrimination regulations and provide direction to clinicians supporting their clients as they confront issues of genetic testing and genetic discrimination. PMID:22453290

A range of complex probabilistic models for RNA secondary structure prediction that includes the nearest-neighbor model and more.

PubMed

Rivas, Elena; Lang, Raymond; Eddy, Sean R

2012-02-01

The standard approach for single-sequence RNA secondary structure prediction uses a nearest-neighbor thermodynamic model with several thousand experimentally determined energy parameters. An attractive alternative is to use statistical approaches with parameters estimated from growing databases of structural RNAs. Good results have been reported for discriminative statistical methods using complex nearest-neighbor models, including CONTRAfold, Simfold, and ContextFold. Little work has been reported on generative probabilistic models (stochastic context-free grammars [SCFGs]) of comparable complexity, although probabilistic models are generally easier to train and to use. To explore a range of probabilistic models of increasing complexity, and to directly compare probabilistic, thermodynamic, and discriminative approaches, we created TORNADO, a computational tool that can parse a wide spectrum of RNA grammar architectures (including the standard nearest-neighbor model and more) using a generalized super-grammar that can be parameterized with probabilities, energies, or arbitrary scores. By using TORNADO, we find that probabilistic nearest-neighbor models perform comparably to (but not significantly better than) discriminative methods. We find that complex statistical models are prone to overfitting RNA structure and that evaluations should use structurally nonhomologous training and test data sets. Overfitting has affected at least one published method (ContextFold). The most important barrier to improving statistical approaches for RNA secondary structure prediction is the lack of diversity of well-curated single-sequence RNA secondary structures in current RNA databases.

A range of complex probabilistic models for RNA secondary structure prediction that includes the nearest-neighbor model and more

PubMed Central

Rivas, Elena; Lang, Raymond; Eddy, Sean R.

2012-01-01

The standard approach for single-sequence RNA secondary structure prediction uses a nearest-neighbor thermodynamic model with several thousand experimentally determined energy parameters. An attractive alternative is to use statistical approaches with parameters estimated from growing databases of structural RNAs. Good results have been reported for discriminative statistical methods using complex nearest-neighbor models, including CONTRAfold, Simfold, and ContextFold. Little work has been reported on generative probabilistic models (stochastic context-free grammars [SCFGs]) of comparable complexity, although probabilistic models are generally easier to train and to use. To explore a range of probabilistic models of increasing complexity, and to directly compare probabilistic, thermodynamic, and discriminative approaches, we created TORNADO, a computational tool that can parse a wide spectrum of RNA grammar architectures (including the standard nearest-neighbor model and more) using a generalized super-grammar that can be parameterized with probabilities, energies, or arbitrary scores. By using TORNADO, we find that probabilistic nearest-neighbor models perform comparably to (but not significantly better than) discriminative methods. We find that complex statistical models are prone to overfitting RNA structure and that evaluations should use structurally nonhomologous training and test data sets. Overfitting has affected at least one published method (ContextFold). The most important barrier to improving statistical approaches for RNA secondary structure prediction is the lack of diversity of well-curated single-sequence RNA secondary structures in current RNA databases. PMID:22194308

Prevalence and Correlates of Perceived Ethnic Discrimination in the Hispanic Community Health Study/Study of Latinos Sociocultural Ancillary Study

PubMed Central

Arellano-Morales, Leticia; Roesch, Scott C.; Gallo, Linda C.; Emory, Kristen T.; Molina, Kristine M.; Gonzalez, Patricia; Penedo, Frank J.; Navas-Nacher, Elena L.; Teng, Yanping; Deng, Yu; Isasi, Carmen R.; Schneiderman, Neil; Brondolo, Elizabeth

2015-01-01

Empirical studies examining perceived ethnic discrimination in Latinos of diverse background groups are limited. This study examined prevalence and correlates of discrimination in a diverse sample of U.S. Latinos (N=5,291) from the multi-site Hispanic Community Health Study/Study of Latinos (HCHS/SOL) and HCHS/SOL Sociocultural Ancillary Study. The sample permitted an examination of differences across seven groups (Central American, Cuban, Dominican, Mexican, Puerto Rican, South American, and Other/Multiple Background). Most participants (79.5%) reported lifetime discrimination exposure and prevalence rates ranged from 64.9% to 98% across groups. Structural Equation Models (SEM) indicated that after adjusting for sociodemographic covariates most group differences in reports of discrimination were eliminated. However, Cubans reported the lowest levels of discrimination, overall among all groups. Furthermore, regional effects were more important than group effects. Participants from Chicago reported the highest levels of discrimination in comparison to other regions. Group differences among Latinos appear to be primarily a function of sociodemographic differences in education, income, and acculturation. In addition, differences in exposure to discrimination may be tied to variables associated with both immigration patterns and integration to U.S. culture. Results highlight the importance of considering historical context and the intersection of discrimination and immigration when evaluating the mental health of Latinos. PMID:26491624

Catheter tracking via online learning for dynamic motion compensation in transcatheter aortic valve implantation.

PubMed

Wang, Peng; Zheng, Yefeng; John, Matthias; Comaniciu, Dorin

2012-01-01

Dynamic overlay of 3D models onto 2D X-ray images has important applications in image guided interventions. In this paper, we present a novel catheter tracking for motion compensation in the Transcatheter Aortic Valve Implantation (TAVI). To address such challenges as catheter shape and appearance changes, occlusions, and distractions from cluttered backgrounds, we present an adaptive linear discriminant learning method to build a measurement model online to distinguish catheters from background. An analytic solution is developed to effectively and efficiently update the discriminant model and to minimize the classification errors between the tracking object and backgrounds. The online learned discriminant model is further combined with an offline learned detector and robust template matching in a Bayesian tracking framework. Quantitative evaluations demonstrate the advantages of this method over current state-of-the-art tracking methods in tracking catheters for clinical applications.

Dynamic elementary mode modelling of non-steady state flux data.

PubMed

Folch-Fortuny, Abel; Teusink, Bas; Hoefsloot, Huub C J; Smilde, Age K; Ferrer, Alberto

2018-06-18

A novel framework is proposed to analyse metabolic fluxes in non-steady state conditions, based on the new concept of dynamic elementary mode (dynEM): an elementary mode activated partially depending on the time point of the experiment. Two methods are introduced here: dynamic elementary mode analysis (dynEMA) and dynamic elementary mode regression discriminant analysis (dynEMR-DA). The former is an extension of the recently proposed principal elementary mode analysis (PEMA) method from steady state to non-steady state scenarios. The latter is a discriminant model that permits to identify which dynEMs behave strongly different depending on the experimental conditions. Two case studies of Saccharomyces cerevisiae, with fluxes derived from simulated and real concentration data sets, are presented to highlight the benefits of this dynamic modelling. This methodology permits to analyse metabolic fluxes at early stages with the aim of i) creating reduced dynamic models of flux data, ii) combining many experiments in a single biologically meaningful model, and iii) identifying the metabolic pathways that drive the organism from one state to another when changing the environmental conditions.

Social context of HIV risk behaviours among male-to-female transgenders of colour.

PubMed

Nemoto, T; Operario, D; Keatley, J; Villegas, D

2004-08-01

To explore the social context of drug use and sexual behaviours that put male-to-female (MTF) transgenders at risk for HIV, focus groups were conducted consisting of African American, Latina and Asian and Pacific Islander MTF transgenders (N = 48) who reside or work in San Francisco, California. Participants were likely to report having unprotected sex with primary partners to signify love and emotional connection, as well as to receive gender validation from their partners. In contrast, viewing sex work with customers as a business encouraged intentious to use condoms. Safer sex intentions with customers were frequently undermined by urgent financial needs, which stemmed from transphobia, employment discrimination and costly procedures associated with gender transition. Participants reported using drugs as a way to cope with or escape life stresses associated with relationships, sex work, transphobia and financial hardship. Interventions with at-risk MTF transgenders should address the interpersonal and social context of unsafe sex and drug use, particularly the unique roles of relationship issues with male partners, stigma, discrimination and community norms regarding sex work and drug use.

A Solar Cycle Dependence of Nonlinearity in Magnetospheric Activity

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

Johnson, Jay R; Wing, Simon

2005-03-08

The nonlinear dependencies inherent to the historical K(sub)p data stream (1932-2003) are examined using mutual information and cumulant based cost as discriminating statistics. The discriminating statistics are compared with surrogate data streams that are constructed using the corrected amplitude adjustment Fourier transform (CAAFT) method and capture the linear properties of the original K(sub)p data. Differences are regularly seen in the discriminating statistics a few years prior to solar minima, while no differences are apparent at the time of solar maximum. These results suggest that the dynamics of the magnetosphere tend to be more linear at solar maximum than at solarmore » minimum. The strong nonlinear dependencies tend to peak on a timescale around 40-50 hours and are statistically significant up to one week. Because the solar wind driver variables, VB(sub)s and dynamical pressure exhibit a much shorter decorrelation time for nonlinearities, the results seem to indicate that the nonlinearity is related to internal magnetospheric dynamics. Moreover, the timescales for the nonlinearity seem to be on the same order as that for storm/ring current relaxation. We suggest that the strong solar wind driving that occurs around solar maximum dominates the magnetospheric dynamics suppressing the internal magnetospheric nonlinearity. On the other hand, in the descending phase of the solar cycle just prior to solar minimum, when magnetospheric activity is weaker, the dynamics exhibit a significant nonlinear internal magnetospheric response that may be related to increased solar wind speed.« less

Perceived racial discrimination and negative-mood-related drinking among African American college students.

PubMed

O'Hara, Ross E; Armeli, Stephen; Scott, Denise M; Covault, Jonathan; Tennen, Howard

2015-03-01

Research consistently shows a positive association between racial discrimination and problematic alcohol use among African Americans, but little is known about the micro-processes linking this pernicious form of stress to drinking. One possibility is that the cumulative effects of discrimination increase individuals' likelihood of negative-mood-related drinking. In the current study, we examined whether individual differences in lifetime perceived racial discrimination among African American college students moderate relations between daily negative moods and evening alcohol consumption in both social and nonsocial contexts. Data came from an online daily diary study of 441 African Americans (58% female) enrolled at a historically black college/university. Lifetime discrimination was measured at baseline. For 30 days, students reported the number of drinks they consumed the night before both socially and nonsocially, as well as their daytime level of negative mood. In support of the hypotheses, only men who reported higher (vs. lower) lifetime discrimination showed a positive association between daily negative mood and that evening's level of nonsocial drinking. Contrary to expectation, women who reported higher (vs. lower) discrimination showed a negative association between daily negative mood and nonsocial drinking. Neither daily negative mood nor lifetime discrimination predicted level of social drinking. These findings provide further evidence that the cumulative impact of racial discrimination may produce a vulnerability to negative-mood-related drinking--but only for African American men. Importantly, these effects emerged only for nonsocial drinking, which may further explain the robust association between discrimination and problematic alcohol use.

Socioeconomic Status Discrimination is Associated with Poor Sleep in African-Americans, but not Whites

PubMed Central

Van Dyke, Miriam E.; Vaccarino, Viola; Quyyumi, Arshed A.; Lewis, Tené T.

2016-01-01

Rationale Research on self-reported experiences of discrimination and health has grown in recent decades, but has largely focused on racial discrimination or overall mistreatment. Less is known about reports of discrimination on the basis of socioeconomic status (SES), despite the fact that SES is one of the most powerful social determinants of health. Objective We sought to examine the cross-sectional association between self-reported SES discrimination and subjective sleep quality, an emerging risk factor for disease. We further examined whether associations differed by race or SES. Methods We used logistic and linear regression to analyze data from a population-based cohort of 425 African-American and White middle-aged adults (67.5% female) in the Southeastern United States. SES discrimination was assessed with a modified Experiences of Discrimination Scale and poor subjective sleep quality was assessed with the Pittsburgh Sleep Quality Index. Results In logistic regression models adjusted for age, gender, and education, reports of SES discrimination were associated with poor sleep quality among African-Americans (OR=2.39, 95% CI =1.35, 4.24), but not Whites (OR=1.03, 95% CI= 0.57, 1.87), and the race × SES discrimination interaction was significant at p=0.04. After additional adjustments for reports of racial and gender discrimination, other psychosocial stressors, body mass index and depressive symptoms, SES discrimination remained a significant predictor of poor sleep among African-Americans, but not Whites. In contrast to findings by race, SES discrimination and sleep associations did not significantly differ by SES. Conclusion Findings suggest that reports of SES discrimination may be an important risk factor for subjective sleep quality among African-Americans and support the need to consider the health impact of SES-related stressors in the context of race. PMID:26896878

Socioeconomic status discrimination is associated with poor sleep in African-Americans, but not Whites.

PubMed

Van Dyke, Miriam E; Vaccarino, Viola; Quyyumi, Arshed A; Lewis, Tené T

2016-03-01

Research on self-reported experiences of discrimination and health has grown in recent decades, but has largely focused on racial discrimination or overall mistreatment. Less is known about reports of discrimination on the basis of socioeconomic status (SES), despite the fact that SES is one of the most powerful social determinants of health. We sought to examine the cross-sectional association between self-reported SES discrimination and subjective sleep quality, an emerging risk factor for disease. We further examined whether associations differed by race or SES. We used logistic and linear regression to analyze data from a population-based cohort of 425 African-American and White middle-aged adults (67.5% female) in the Southeastern United States. SES discrimination was assessed with a modified Experiences of Discrimination Scale and poor subjective sleep quality was assessed with the Pittsburgh Sleep Quality Index. In logistic regression models adjusted for age, gender, and education, reports of SES discrimination were associated with poor sleep quality among African-Americans (OR = 2.39 95%, CI = 1.35, 4.24), but not Whites (OR = 1.03, 95% CI = 0.57, 1.87), and the race × SES discrimination interaction was significant at p = 0.04. After additional adjustments for reports of racial and gender discrimination, other psychosocial stressors, body mass index and depressive symptoms, SES discrimination remained a significant predictor of poor sleep among African-Americans, but not Whites. In contrast to findings by race, SES discrimination and sleep associations did not significantly differ by SES. Findings suggest that reports of SES discrimination may be an important risk factor for subjective sleep quality among African-Americans and support the need to consider the health impact of SES-related stressors in the context of race. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Dynamic Ubiquitous Learning Resource Model with Context and Its Effects on Ubiquitous Learning

ERIC Educational Resources Information Center

Chen, Min; Yu, Sheng Quan; Chiang, Feng Kuang

2017-01-01

Most ubiquitous learning researchers use resource recommendation and retrieving based on context to provide contextualized learning resources, but it is the kind of one-way context matching. Learners always obtain fixed digital learning resources, which present all learning contents in any context. This study proposed a dynamic ubiquitous learning…

Perceptions of legal status: Associations with psychosocial experiences among undocumented Latino/a immigrants.

PubMed

Cobb, Cory L; Meca, Alan; Xie, Dong; Schwartz, Seth J; Moise, Rhoda K

2017-03-01

In the present study we used a mixed-method design to examine perceptions of legal status and their association with psychosocial experiences among undocumented Latino/a immigrants in the United States Participants were asked to compare their perceived social experiences with those of documented Latinos/as in order to determine whether differences in such perceptions might emerge and whether such perceptions might differentially impact well-being. A community sample of 140 self-reported undocumented Latino/a immigrants completed questionnaires measuring perceptions of legal status, well-being (global and psychological), perceived context of reception, and experiences of discrimination. Results indicated that individuals who perceived their experiences as different from those of documented Latinos/as due to an unauthorized legal status reported less social equality as evidenced by lower well-being, increased experiences of discrimination, and a more adverse context of reception. Moreover, individuals who perceived their social experiences as different from those of documented Latinos/as due to their legal status reported issues centering on 2 domains: limited opportunity/restricted social mobility and discrimination/unfair treatment. Theoretical and practical implications are discussed in terms of advancing theory and from a multicultural counseling perspective. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The Good, The Bad and The Ugly: Disaster Risk Reduction (DRR) Versus Disaster Risk Creation (DRC)

PubMed Central

Lewis, James

2012-01-01

In understanding and trying to reduce the risk from disasters, connections are often articulated amongst poverty, vulnerability, risk, and disasters. These are welcome steps, but the approach taken in top-down international documents is rarely to articulate explicitly that vulnerability accrues from a wide variety of dynamic and long-term processes. Neglecting these processes—and failing to explore their links with poverty, risk, and disasters—tends to encourage disaster risk creation. This paper identifies seven examples of on-the-ground realities of long-term vulnerability within two clusters: Endangerment: 1 Environmental degradation. 2 Discrimination. 3 Displacement. Impoverishment: 4 Self-seeking public expenditure. 5 Denial of access to resources. 6 Corruption. 7 Siphoning of public money. Examples are presented as vignettes, many contemporary and many rooted in historical contexts, to demonstrate the extent to which “vulnerability drivers” emanate from greed, the misuse of political and commercial power, mismanagement and incompetence amongst other behaviours. Moving forward to the tackling of disaster risk creation, instead of simply seeking disaster risk reduction, requires detailed investigation into these contemporary and historical realities of the causes of vulnerability. That would support the integration of disaster risk reduction within the many wider contexts that foment and perpetuate vulnerability. PMID:22919564

Defining and quantifying the resilience of responses to disturbance: a conceptual and modelling approach from soil science

PubMed Central

Todman, L. C.; Fraser, F. C.; Corstanje, R.; Deeks, L. K.; Harris, J. A.; Pawlett, M.; Ritz, K.; Whitmore, A. P.

2016-01-01

There are several conceptual definitions of resilience pertaining to environmental systems and, even if resilience is clearly defined in a particular context, it is challenging to quantify. We identify four characteristics of the response of a system function to disturbance that relate to “resilience”: (1) degree of return of the function to a reference level; (2) time taken to reach a new quasi-stable state; (3) rate (i.e. gradient) at which the function reaches the new state; (4) cumulative magnitude of the function (i.e. area under the curve) before a new state is reached. We develop metrics to quantify these characteristics based on an analogy with a mechanical spring and damper system. Using the example of the response of a soil function (respiration) to disturbance, we demonstrate that these metrics effectively discriminate key features of the dynamic response. Although any one of these characteristics could define resilience, each may lead to different insights and conclusions. The salient properties of a resilient response must thus be identified for different contexts. Because the temporal resolution of data affects the accurate determination of these metrics, we recommend that at least twelve measurements are made over the temporal range for which the response is expected. PMID:27329053

The Good, The Bad and The Ugly: Disaster Risk Reduction (DRR) Versus Disaster Risk Creation (DRC).

PubMed

Lewis, James

2012-06-21

In understanding and trying to reduce the risk from disasters, connections are often articulated amongst poverty, vulnerability, risk, and disasters. These are welcome steps, but the approach taken in top-down international documents is rarely to articulate explicitly that vulnerability accrues from a wide variety of dynamic and long-term processes. Neglecting these processes-and failing to explore their links with poverty, risk, and disasters-tends to encourage disaster risk creation. This paper identifies seven examples of on-the-ground realities of long-term vulnerability within two clusters: Endangerment: 1 Environmental degradation. 2 Discrimination. 3 Displacement. Impoverishment: 4 Self-seeking public expenditure. 5 Denial of access to resources. 6 Corruption. 7 Siphoning of public money. Examples are presented as vignettes, many contemporary and many rooted in historical contexts, to demonstrate the extent to which "vulnerability drivers" emanate from greed, the misuse of political and commercial power, mismanagement and incompetence amongst other behaviours. Moving forward to the tackling of disaster risk creation, instead of simply seeking disaster risk reduction, requires detailed investigation into these contemporary and historical realities of the causes of vulnerability. That would support the integration of disaster risk reduction within the many wider contexts that foment and perpetuate vulnerability.

East Asian adolescents' ethnic identity development and cultural integration: A qualitative investigation.

PubMed

Yoon, Eunju; Adams, Kristen; Clawson, Angela; Chang, Hanna; Surya, Shruti; Jérémie-Brink, Gihane

2017-01-01

Drawing on the current conceptualization of acculturation/enculturation as bilinear, multidimensional processes proceeding in interaction with surrounding contexts, this study examined ethnic identity development and cultural integration of 13 adolescents from East Asian immigrant families. Five domains emerged via the Consensual Qualitative Research method: ethnic/cultural identity and socialization; bicultural living; racial context-racism and stereotypes; family context-parental expectation; and peer context-friendship/dating. Overall, the participants experienced a cultural split and discontinuity between the 2 worlds of home and ethnic community versus school and society in general. They received strong ethnic socialization messages from family and ethnic community. Although most participants experienced hurtful racial discrimination, they used passive coping (e.g., dismiss, minimize, defend perpetrators). The model minority stereotype was prevalent and deeply engrained in many aspects of their lives including ethnic identity development, cultural socialization messages from mainstream society, discrimination experiences, and academic/occupational demands imposed by self, parents, peers, and society. Although they appreciated parents' high expectations of academic/occupational success, they felt pressured and desired to have space and independence. Friendship/dating patterns reflected ethnic identity development as well as contextual influence. Implications for research and practice are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Acoustic Characteristics of Long Calls Produced by Male Orang-Utans (Pongo pygmaeus wurmbii): Advertising Individual Identity, Context, and Travel Direction.

PubMed

Askew, James A; Morrogh-Bernard, Helen C

2016-01-01

Acoustic characteristics and context of the long-distance call of male orang-utans (Pongo pygmaeus wurmbii) were examined in a population of orang-utans from Central Kalimantan, Borneo. Male orang-utans produced long calls under different circumstances, including calls made spontaneously, in response to conspecifics, when accompanied by a snag crash and when travelling with a female. It was shown by acoustic analyses that there was individual discrimination between the male's calls, discrimination between the calls made under different contexts, and between calls from one individual from different years, which coincided with a change in his dominance status. We also confirm that flanged male orang-utans advertise their intended travel route, by long calling in the direction of their travel. If other orang-utans (males and females) within ear shot of the caller can identify the caller from their long call, and even obtain information about the context and status of the individual, they can then therefore choose whether to approach or avoid them. Thus, males seem to be using their long call to announce their presence, allowing them to orient themselves spatially to other orang-utans, and, potentially, to co-ordinate a network of loose associations between both males and females in the area. © 2016 S. Karger AG, Basel.

Perceived discrimination and depressive symptoms among immigrant-origin adolescents.

PubMed

Tummala-Narra, Pratyusha; Claudius, Milena

2013-07-01

Although discrimination has been found to contribute to psychological distress among immigrant populations, there are few studies that have examined the relationship between racial and ethnic discrimination in the school setting among foreign-born immigrant and U.S.-born immigrant-origin adolescents. This study examined the relationship between perceived discrimination by adults and peers in the school setting and depressive symptoms in a sample (N = 95) of racial minority immigrant-origin adolescents (13 to 19 years of age) attending an urban high school. We examined the relation between perceived discrimination and depressive symptomology across gender and nativity status (foreign born vs. U.S. born), and the potential moderating role of ethnic identity and social support. Consistent with previous research, girls reported higher levels of depressive symptomology than boys, although the relationship between perceived discrimination and depressive symptoms was significant for both boys and girls. Perceived discrimination by adults and by peers at school was positively related to depressive symptoms for U.S.-born adolescents. For U.S.-born adolescents, ethnic identity mitigated the negative effects of perceived adult discrimination on depressive symptoms. However, ethnic identity did not moderate the relationship between perceived peer discrimination and depressive symptoms. Social support did not moderate the relationship between adult and peer discrimination and depressive symptoms for either foreign-born or U.S.-born adolescents. The findings support previous research concerning the immigrant paradox and highlight the importance of context in the relationship between perceived discrimination and mental health. Implications for future research and intervention are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Awareness Programs and Change in Taste-Based Caste Prejudice

PubMed Central

Banerjee, Ritwik; Datta Gupta, Nabanita

2015-01-01

Becker's theory of taste-based discrimination predicts that relative employment of the discriminated social group will improve if there is a decrease in the level of prejudice for the marginally discriminating employer. In this paper we experimentally test this prediction offered by Garry Becker in his seminal work on taste based discrimination, in the context of caste in India, with management students (potential employers in the near future) as subjects. First, we measure caste prejudice and show that awareness through a TV social program reduces implicit prejudice against the lower caste and the reduction is sustained over time. Second, we find that the treatment reduces the prejudice levels of those in the left tail of the prejudice distribution - the group which can potentially affect real outcomes as predicted by the theory. And finally, a larger share of the treatment group subjects exhibit favorable opinion about reservation in jobs for the lower caste. PMID:25902290

Awareness programs and change in taste-based caste prejudice.

PubMed

Banerjee, Ritwik; Datta Gupta, Nabanita

2015-01-01

Becker's theory of taste-based discrimination predicts that relative employment of the discriminated social group will improve if there is a decrease in the level of prejudice for the marginally discriminating employer. In this paper we experimentally test this prediction offered by Garry Becker in his seminal work on taste based discrimination, in the context of caste in India, with management students (potential employers in the near future) as subjects. First, we measure caste prejudice and show that awareness through a TV social program reduces implicit prejudice against the lower caste and the reduction is sustained over time. Second, we find that the treatment reduces the prejudice levels of those in the left tail of the prejudice distribution--the group which can potentially affect real outcomes as predicted by the theory. And finally, a larger share of the treatment group subjects exhibit favorable opinion about reservation in jobs for the lower caste.

Parental and Infant Gender Factors in Parent-Infant Interaction: State-Space Dynamic Analysis.

PubMed

Cerezo, M Angeles; Sierra-García, Purificación; Pons-Salvador, Gemma; Trenado, Rosa M

2017-01-01

This study aimed to investigate the influence of parental gender on their interaction with their infants, considering, as well, the role of the infant's gender. The State Space Grid (SSG) method, a graphical tool based on the non-linear dynamic system (NDS) approach was used to analyze the interaction, in Free-Play setting, of 52 infants, aged 6 to 10 months, divided into two groups: half of the infants interacted with their fathers and half with their mothers. There were 50% boys in each group. MANOVA results showed no differential parenting of boys and girls. Additionally, mothers and fathers showed no differences in the Diversity of behavioral dyadic states nor in Predictability. However, differences associated with parent's gender were found in that the paternal dyads were more "active" than the maternal dyads: they were faster in the rates per second of behavioral events and transitions or change of state. In contrast, maternal dyads were more repetitive because, once they visited a certain dyadic state, they tend to be involved in more events. Results showed a significant discriminant function on the parental groups, fathers and mothers. Specifically, the content analyses carried out for the three NDS variables, that previously showed differences between groups, showed particular dyadic behavioral states associated with the rate of Transitions and the Events per Visit ratio. Thus, the transitions involving 'in-out' of 'Child Social Approach neutral - Sensitive Approach neutral' state and the repetitions of events in the dyadic state 'Child Play-Sensitive Approach neutral' distinguished fathers from mothers. The classification of dyads (with fathers and mothers) based on this discriminant function identified 73.10% (19/26) of the father-infant dyads and 88.5% (23/26) of the mother-infant dyads. The study of father-infant interaction using the SSG approach offers interesting possibilities because it characterizes and quantifies the actual moment-to-moment flow of parent-infant interactive dynamics. Our findings showed how observational methods applied to natural contexts offer new facets in father vs. mother interactive behavior with their infants that can inform further developments in this field.

Batch process fault detection and identification based on discriminant global preserving kernel slow feature analysis.

PubMed

Zhang, Hanyuan; Tian, Xuemin; Deng, Xiaogang; Cao, Yuping

2018-05-16

As an attractive nonlinear dynamic data analysis tool, global preserving kernel slow feature analysis (GKSFA) has achieved great success in extracting the high nonlinearity and inherently time-varying dynamics of batch process. However, GKSFA is an unsupervised feature extraction method and lacks the ability to utilize batch process class label information, which may not offer the most effective means for dealing with batch process monitoring. To overcome this problem, we propose a novel batch process monitoring method based on the modified GKSFA, referred to as discriminant global preserving kernel slow feature analysis (DGKSFA), by closely integrating discriminant analysis and GKSFA. The proposed DGKSFA method can extract discriminant feature of batch process as well as preserve global and local geometrical structure information of observed data. For the purpose of fault detection, a monitoring statistic is constructed based on the distance between the optimal kernel feature vectors of test data and normal data. To tackle the challenging issue of nonlinear fault variable identification, a new nonlinear contribution plot method is also developed to help identifying the fault variable after a fault is detected, which is derived from the idea of variable pseudo-sample trajectory projection in DGKSFA nonlinear biplot. Simulation results conducted on a numerical nonlinear dynamic system and the benchmark fed-batch penicillin fermentation process demonstrate that the proposed process monitoring and fault diagnosis approach can effectively detect fault and distinguish fault variables from normal variables. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

A Social Approach to High-Level Context Generation for Supporting Context-Aware M-Learning

ERIC Educational Resources Information Center

Pan, Xu-Wei; Ding, Ling; Zhu, Xi-Yong; Yang, Zhao-Xiang

2017-01-01

In m-learning environments, context-awareness is for wide use where learners' situations are varied, dynamic and unpredictable. We are facing the challenge of requirements of both generality and depth in generating and processing high-level context. In this paper, we present a social approach which exploits social dynamics and social computing for…

Spectrotemporal weighting of binaural cues: Effects of a diotic interferer on discrimination of dynamic interaural differences

PubMed Central

Bibee, Jacqueline M.; Stecker, G. Christopher

2016-01-01

Spatial judgments are often dominated by low-frequency binaural cues and onset cues when binaural cues vary across the spectrum and duration, respectively, of a brief sound. This study combined these dimensions to assess the spectrotemporal weighting of binaural information. Listeners discriminated target interaural time difference (ITD) and interaural level difference (ILD) carried by the onset, offset, or full duration of a 4-kHz Gabor click train with a 2-ms period in the presence or absence of a diotic 500-Hz interferer tone. ITD and ILD thresholds were significantly elevated by the interferer in all conditions and by a similar amount to previous reports for static cues. Binaural interference was dramatically greater for ITD targets lacking onset cues compared to onset and full-duration conditions. Binaural interference for ILD targets was similar across dynamic-cue conditions. These effects mirror the baseline discriminability of dynamic ITD and ILD cues [Stecker and Brown. (2010). J. Acoust. Soc. Am. 127, 3092–3103], consistent with stronger interference for less-robust/higher-variance cues. The results support the view that binaural cue integration occurs simultaneously across multiple variance-weighted dimensions, including time and frequency. PMID:27794286

Spectrotemporal weighting of binaural cues: Effects of a diotic interferer on discrimination of dynamic interaural differences.

PubMed

Bibee, Jacqueline M; Stecker, G Christopher

2016-10-01

Spatial judgments are often dominated by low-frequency binaural cues and onset cues when binaural cues vary across the spectrum and duration, respectively, of a brief sound. This study combined these dimensions to assess the spectrotemporal weighting of binaural information. Listeners discriminated target interaural time difference (ITD) and interaural level difference (ILD) carried by the onset, offset, or full duration of a 4-kHz Gabor click train with a 2-ms period in the presence or absence of a diotic 500-Hz interferer tone. ITD and ILD thresholds were significantly elevated by the interferer in all conditions and by a similar amount to previous reports for static cues. Binaural interference was dramatically greater for ITD targets lacking onset cues compared to onset and full-duration conditions. Binaural interference for ILD targets was similar across dynamic-cue conditions. These effects mirror the baseline discriminability of dynamic ITD and ILD cues [Stecker and Brown. (2010). J. Acoust. Soc. Am. 127, 3092-3103], consistent with stronger interference for less-robust/higher-variance cues. The results support the view that binaural cue integration occurs simultaneously across multiple variance-weighted dimensions, including time and frequency.

Chern-Simons Modified Gravity

NASA Astrophysics Data System (ADS)

Efstratiou, P.

2013-09-01

This presentation will be based on my, undergraduate, thesis at Aristotle University of Thessoliniki with the same subject, supervised by Professor Demetrios Papadopoulos. I will first present the general mathematical formulation of the Chern-Simons (CS) modified gravity, which is split in a dynamical and a non-dynamical context, and the different physical theories which suggest this modification. Then proceed by examing the possibility that the CS theory shares solutions with General Relativity in both contexts. In the non-dynamical context I will present a new, undocumented solution as well as all the other possible solutions found to date. I will conclude by arguing that General Relativity and CS Theory share any solutions in the dynamical context.

Associations of racial discrimination and parental discrimination coping messages with African American adolescent racial identity.

PubMed

Richardson, Bridget L; Macon, Tamarie A; Mustafaa, Faheemah N; Bogan, Erin D; Cole-Lewis, Yasmin; Chavous, Tabbye M

2015-06-01

Research links racial identity to important developmental outcomes among African American adolescents, but less is known about the contextual experiences that shape youths' racial identity. In a sample of 491 African American adolescents (48% female), associations of youth-reported experiences of racial discrimination and parental messages about preparation for racial bias with adolescents' later racial identity were examined. Cluster analysis resulted in four profiles of adolescents varying in reported frequency of racial discrimination from teachers and peers at school and frequency of parental racial discrimination coping messages during adolescents' 8th grade year. Boys were disproportionately over-represented in the cluster of youth experiencing more frequent discrimination but receiving fewer parental discrimination coping messages, relative to the overall sample. Also examined were clusters of adolescents' 11th grade racial identity attitudes about the importance of race (centrality), personal group affect (private regard), and perceptions of societal beliefs about African Americans (public regard). Girls and boys did not differ in their representation in racial identity clusters, but 8th grade discrimination/parent messages clusters were associated with 11th grade racial identity cluster membership, and these associations varied across gender groups. Boys experiencing more frequent discrimination but fewer parental coping messages were over-represented in the racial identity cluster characterized by low centrality, low private regard, and average public regard. The findings suggest that adolescents who experience racial discrimination but receive fewer parental supports for negotiating and coping with discrimination may be at heightened risk for internalizing stigmatizing experiences. Also, the findings suggest the need to consider the context of gender in adolescents' racial discrimination and parental racial socialization.

Behavioral evidence for community-wide species discrimination from echolocation calls in bats.

PubMed

Schuchmann, Maike; Siemers, Björn M

2010-07-01

Recognizing species identity is crucial for many aspects of animal life and is often mediated by acoustic signals. Although most animals are able to distinguish acoustic signals of their own species from other sympatrically occurring species, it is yet unknown whether animals can distinguish among acoustic signals of different closely related sympatric species. In this context, echolocating bats are a particularly interesting model system: their echolocation system evolved primarily for spatial orientation and foraging, but recent studies indicate that echolocation also has an important communicative function. Yet, the role of echolocation calls for species discrimination and thus potentially for interspecific communication has not been investigated. Using a behavioral discrimination assay, we found that two species of wild horseshoe bats could discriminate calls of their own species from those of three sympatric congeneric species. We further show that the bats were able to discriminate between echolocation calls of different congeneric species from the local community. In both cases, discrimination ability was high despite strong overlap of species' call frequency bands. This study provides the first experimental evidence for species discrimination based on echolocation calls. On a more general level, it shows for the first time that animals can distinguish among acoustic signals of different closely related and ecologically similar species from their local community.

Does overall reinforcer rate affect discrimination of time-based contingencies?

PubMed

Cowie, Sarah; Davison, Michael; Blumhardt, Luca; Elliffe, Douglas

2016-05-01

Overall reinforcer rate appears to affect choice. The mechanism for such an effect is uncertain, but may relate to reinforcer rate changing the discrimination of the relation between stimuli and reinforcers. We assessed whether a quantitative model based on a stimulus-control approach could be used to account for the effects of overall reinforcer rate on choice under changing time-based contingencies. On a two-key concurrent schedule, the likely availability of a reinforcer reversed when a fixed time had elapsed since the last reinforcer, and the overall reinforcer rate was varied across conditions. Changes in the overall reinforcer rate produced a change in response bias, and some indication of a change in discrimination. These changes in bias and discrimination always occurred quickly, usually within the first session of a condition. The stimulus-control approach provided an excellent account of the data, suggesting that changes in overall reinforcer rate affect choice because they alter the frequency of reinforcers obtained at different times, or in different stimulus contexts, and thus change the discriminated relation between stimuli and reinforcers. These findings support the notion that temporal and spatial discriminations can be understood in terms of discrimination of reinforcers across time and space. © 2016 Society for the Experimental Analysis of Behavior.

Explaining negative kin discrimination in a cooperative mammal society

PubMed Central

Cant, Michael A.; Sanderson, Jennifer L.; Gilchrist, Jason S.; Bell, Matthew B. V.; Hodge, Sarah J.; Johnstone, Rufus A.

2017-01-01

Kin selection theory predicts that, where kin discrimination is possible, animals should typically act more favorably toward closer genetic relatives and direct aggression toward less closely related individuals. Contrary to this prediction, we present data from an 18-y study of wild banded mongooses, Mungos mungo, showing that females that are more closely related to dominant individuals are specifically targeted for forcible eviction from the group, often suffering severe injury, and sometimes death, as a result. This pattern cannot be explained by inbreeding avoidance or as a response to more intense local competition among kin. Instead, we use game theory to show that such negative kin discrimination can be explained by selection for unrelated targets to invest more effort in resisting eviction. Consistent with our model, negative kin discrimination is restricted to eviction attempts of older females capable of resistance; dominants exhibit no kin discrimination when attempting to evict younger females, nor do they discriminate between more closely or less closely related young when carrying out infanticidal attacks on vulnerable infants who cannot defend themselves. We suggest that in contexts where recipients of selfish acts are capable of resistance, the usual prediction of positive kin discrimination can be reversed. Kin selection theory, as an explanation for social behavior, can benefit from much greater exploration of sequential social interactions. PMID:28439031

Health Consequences of Racist and Antigay Discrimination for Multiple Minority Adolescents

PubMed Central

Thoma, Brian C.; Huebner, David M.

2014-01-01

Individuals who belong to a marginalized group and who perceive discrimination based on that group membership suffer from a variety of poor health outcomes. Many people belong to more than one marginalized group, and much less is known about the influence of multiple forms of discrimination on health outcomes. Drawing on literature describing the influence of multiple stressors, three models of combined forms of discrimination are discussed: additive, prominence, and exacerbation. The current study examined the influence of multiple forms of discrimination in a sample of African American lesbian, gay, or bisexual (LGB) adolescents ages 14–19. Each of the three models of combined stressors were tested to determine which best describes how racist and antigay discrimination combine to predict depressive symptoms, suicidal ideation, and substance use. Participants were included in this analysis if they identified their ethnicity as either African American (n = 156) or African American mixed (n = 120). Mean age was 17.45 years (SD = 1.36). Results revealed both forms of mistreatment were associated with depressive symptoms and suicidal ideation among African American LGB adolescents. Racism was more strongly associated with substance use. Future intervention efforts should be targeted toward reducing discrimination and improving the social context of multiple minority adolescents, and future research with multiple minority individuals should be attuned to the multiple forms of discrimination experienced by these individuals within their environments. PMID:23731232

Diverse Region-Based CNN for Hyperspectral Image Classification.

PubMed

Zhang, Mengmeng; Li, Wei; Du, Qian

2018-06-01

Convolutional neural network (CNN) is of great interest in machine learning and has demonstrated excellent performance in hyperspectral image classification. In this paper, we propose a classification framework, called diverse region-based CNN, which can encode semantic context-aware representation to obtain promising features. With merging a diverse set of discriminative appearance factors, the resulting CNN-based representation exhibits spatial-spectral context sensitivity that is essential for accurate pixel classification. The proposed method exploiting diverse region-based inputs to learn contextual interactional features is expected to have more discriminative power. The joint representation containing rich spectral and spatial information is then fed to a fully connected network and the label of each pixel vector is predicted by a softmax layer. Experimental results with widely used hyperspectral image data sets demonstrate that the proposed method can surpass any other conventional deep learning-based classifiers and other state-of-the-art classifiers.

Behavioral momentum theory: equations and applications.

PubMed

Nevin, John A; Shahan, Timothy A

2011-01-01

Behavioral momentum theory provides a quantitative account of how reinforcers experienced within a discriminative stimulus context govern the persistence of behavior that occurs in that context. The theory suggests that all reinforcers obtained in the presence of a discriminative stimulus increase resistance to change, regardless of whether those reinforcers are contingent on the target behavior, are noncontingent, or are even contingent on an alternative behavior. In this paper, we describe the equations that constitute the theory and address their application to issues of particular importance in applied settings. The theory provides a framework within which to consider the effects of interventions such as extinction, noncontingent reinforcement, differential reinforcement of alternative behavior, and other phenomena (e.g., resurgence). Finally, the theory predicts some counterintuitive and potentially counterproductive effects of alternative reinforcement, and can serve as an integrative guide for intervention when its terms are identified with the relevant conditions of applied settings.

Pitch and time, tonality and meter: how do musical dimensions combine?

PubMed

Prince, Jon B; Thompson, William F; Schmuckler, Mark A

2009-10-01

The authors examined how the structural attributes of tonality and meter influence musical pitch-time relations. Listeners heard a musical context followed by probe events that varied in pitch class and temporal position. Tonal and metric hierarchies contributed additively to the goodness-of-fit of probes, with pitch class exerting a stronger influence than temporal position (Experiment 1), even when listeners attempted to ignore pitch (Experiment 2). Speeded classification tasks confirmed this asymmetry. Temporal classification was biased by tonal stability (Experiment 3), but pitch classification was unaffected by temporal position (Experiment 4). Experiments 5 and 6 ruled out explanations based on the presence of pitch classes and temporal positions in the context, unequal stimulus quantity, and discriminability. The authors discuss how typical Western music biases attention toward pitch and distinguish between dimensional discriminability and salience. PsycINFO Database Record (c) 2009 APA, all rights reserved.

A simple and fast representation space for classifying complex time series

NASA Astrophysics Data System (ADS)

Zunino, Luciano; Olivares, Felipe; Bariviera, Aurelio F.; Rosso, Osvaldo A.

2017-03-01

In the context of time series analysis considerable effort has been directed towards the implementation of efficient discriminating statistical quantifiers. Very recently, a simple and fast representation space has been introduced, namely the number of turning points versus the Abbe value. It is able to separate time series from stationary and non-stationary processes with long-range dependences. In this work we show that this bidimensional approach is useful for distinguishing complex time series: different sets of financial and physiological data are efficiently discriminated. Additionally, a multiscale generalization that takes into account the multiple time scales often involved in complex systems has been also proposed. This multiscale analysis is essential to reach a higher discriminative power between physiological time series in health and disease.

Dynamic Dimensionality Selection for Bayesian Classifier Ensembles

DTIC Science & Technology

2015-03-19

learning of weights in an otherwise generatively learned naive Bayes classifier. WANBIA-C is very cometitive to Logistic Regression but much more...classifier, Generative learning, Discriminative learning, Naïve Bayes, Feature selection, Logistic regression , higher order attribute independence 16...discriminative learning of weights in an otherwise generatively learned naive Bayes classifier. WANBIA-C is very cometitive to Logistic Regression but

Bacillus subtilis Protects Public Goods by Extending Kin Discrimination to Closely Related Species.

PubMed

Lyons, Nicholas A; Kolter, Roberto

2017-07-05

Kin discrimination systems are found in numerous communal contexts like multicellularity and are theorized to prevent exploitation of cooperative behaviors. The kin discrimination system in Bacillus subtilis differs from most other such systems because it excludes nonkin cells rather than including kin cells. Because nonkin are the target of the system, B. subtilis can potentially distinguish degrees of nonkin relatedness, not just kin versus nonkin. We examined this by testing a large strain collection of diverse Bacillus species against B. subtilis in different multicellular contexts. The effects of kin discrimination extend to nearby species, as the other subtilis clade species were treated with the same antagonism as nonkin. Species in the less-related pumilus clade started to display varied phenotypes but were mostly still discriminated against, while cereus clade members and beyond were no longer subject to kin discrimination. Seeking a reason why other species are perceived as antagonistic nonkin, we tested the ability of B. subtilis to steal communally produced surfactant from these species. We found that the species treated as nonkin were the only ones that made a surfactant that B. subtilis could utilize and that nonkin antagonism prevented such stealing when the two strains were mixed. The nonkin exclusion kin discrimination method thus allows effective protection of the cooperative behaviors prevalent in multicellularity while still permitting interactions with more distant species that are not a threat. IMPORTANCE Multicellular systems like bacterial biofilms and swarms rely on cooperative behaviors that could be undermined by exploitative invaders. Discriminating kin from nonkin is one way to help guard against such exploitation but has thus far been examined only intraspecifically, so the phylogenetic range of this important trait is unknown. We tested whether Bacillus subtilis treats other species as nonkin by testing a single strain against a diverse collection of Bacillus isolates. We found that the species in the same clade were treated as nonkin, which then lessened in more distant relatives. Further experiments showed that these nonkin species produced a cooperative good that could be stolen by B. subtilis and that treating each other as nonkin largely prevented this exploitation. These results impact our understanding of interspecies interactions, as bacterial populations can interact only after they have diverged enough to no longer be a threat to their cooperative existences. Copyright © 2017 Lyons and Kolter.

A note on the stability and discriminability of graph-based features for classification problems in digital pathology

NASA Astrophysics Data System (ADS)

Cruz-Roa, Angel; Xu, Jun; Madabhushi, Anant

2015-01-01

Nuclear architecture or the spatial arrangement of individual cancer nuclei on histopathology images has been shown to be associated with different grades and differential risk for a number of solid tumors such as breast, prostate, and oropharyngeal. Graph-based representations of individual nuclei (nuclei representing the graph nodes) allows for mining of quantitative metrics to describe tumor morphology. These graph features can be broadly categorized into global and local depending on the type of graph construction method. While a number of local graph (e.g. Cell Cluster Graphs) and global graph (e.g. Voronoi, Delaunay Triangulation, Minimum Spanning Tree) features have been shown to associated with cancer grade, risk, and outcome for different cancer types, the sensitivity of the preceding segmentation algorithms in identifying individual nuclei can have a significant bearing on the discriminability of the resultant features. This therefore begs the question as to which features while being discriminative of cancer grade and aggressiveness are also the most resilient to the segmentation errors. These properties are particularly desirable in the context of digital pathology images, where the method of slide preparation, staining, and type of nuclear segmentation algorithm employed can all dramatically affect the quality of the nuclear graphs and corresponding features. In this paper we evaluated the trade off between discriminability and stability of both global and local graph-based features in conjunction with a few different segmentation algorithms and in the context of two different histopathology image datasets of breast cancer from whole-slide images (WSI) and tissue microarrays (TMA). Specifically in this paper we investigate a few different performance measures including stability, discriminability and stability vs discriminability trade off, all of which are based on p-values from the Kruskal-Wallis one-way analysis of variance for local and global graph features. Apart from identifying the set of local and global features that satisfied the trade off between stability and discriminability, our most interesting finding was that a simple segmentation method was sufficient to identify the most discriminant features for invasive tumour detection in TMAs, whereas for tumour grading in WSI, the graph based features were more sensitive to the accuracy of the segmentation algorithm employed.

Abnormal early dynamic individual patterns of functional networks in low gamma band for depression recognition.

PubMed

Bi, Kun; Chattun, Mahammad Ridwan; Liu, Xiaoxue; Wang, Qiang; Tian, Shui; Zhang, Siqi; Lu, Qing; Yao, Zhijian

2018-06-13

The functional networks are associated with emotional processing in depression. The mapping of dynamic spatio-temporal brain networks is used to explore individual performance during early negative emotional processing. However, the dysfunctions of functional networks in low gamma band and their discriminative potentialities during early period of emotional face processing remain to be explored. Functional brain networks were constructed from the MEG recordings of 54 depressed patients and 54 controls in low gamma band (30-48 Hz). Dynamic connectivity regression (DCR) algorithm analyzed the individual change points of time series in response to emotional stimuli and constructed individualized spatio-temporal patterns. The nodal characteristics of patterns were calculated and fed into support vector machine (SVM). Performance of the classification algorithm in low gamma band was validated by dynamic topological characteristics of individual patterns in comparison to alpha and beta band. The best discrimination accuracy of individual spatio-temporal patterns was 91.01% in low gamma band. Individual temporal patterns had better results compared to group-averaged temporal patterns in all bands. The most important discriminative networks included affective network (AN) and fronto-parietal network (FPN) in low gamma band. The sample size is relatively small. High gamma band was not considered. The abnormal dynamic functional networks in low gamma band during early emotion processing enabled depression recognition. The individual information processing is crucial in the discovery of abnormal spatio-temporal patterns in depression during early negative emotional processing. Individual spatio-temporal patterns may reflect the real dynamic function of subjects while group-averaged data may neglect some individual information. Copyright © 2018. Published by Elsevier B.V.

Indicators of sailing performance in youth dinghy sailing.

PubMed

Callewaert, Margot; Boone, Jan; Celie, Bert; De Clercq, Dirk; Bourgois, Jan G

2015-01-01

This study aimed to determine indicators of sailing performance in 2 (age) groups of youth sailors by investigating the anthropometric, physical and motor coordination differences and factors discriminating between elite and non-elite male optimist sailors and young dynamic hikers. Anthropometric measurements from 23 optimist sailors (mean ± SD age = 12.3 ± 1.4 years) and 24 dynamic youth hikers (i.e. Laser 4.7, Laser radial and Europe sailors <18 years who have to sail the boat in a very dynamic manner, due to a high sailor to yacht weight ratio) (mean ± SD age = 16.5 ± 1.6 years) were conducted. They performed a physical fitness test battery (EUROFIT), motor coordination test battery (Körperkoordinationstest für Kinder) and the Bucket test. Both groups of sailors were divided into two subgroups (i.e. elites and non-elites) based on sailing expertise. The significant differences, taking biological maturation into account and factors discriminating between elite and non-elite optimist sailors and dynamic hikers were explored by means of multivariate analysis of covariance and discriminant analysis, respectively. The main results indicated that 100.0% of elite optimist sailors and 88.9% of elite dynamic hikers could be correctly classified by means of two motor coordination tests (i.e. side step and side jump) and Bucket test, respectively. As such, strength- and speed-oriented motor coordination and isometric knee-extension strength endurance can be identified as indicators of sailing performance in young optimist and dynamic youth sailors, respectively. Therefore, we emphasise the importance of motor coordination skill training in optimist sailors (<15 years) and maximum strength training later on (>15 years) in order to increase their isometric knee-extension strength endurance.

Experiences of transgender-related discrimination and implications for health: results from the Virginia Transgender Health Initiative Study.

PubMed

Bradford, Judith; Reisner, Sari L; Honnold, Julie A; Xavier, Jessica

2013-10-01

We examined relationships between social determinants of health and experiences of transgender-related discrimination reported by transgender people in Virginia. In 2005 through 2006, 387 self-identified transgender people completed a statewide health needs assessment; 350 who completed eligibility questions were included in this examination of factors associated with experiences of discrimination in health care, employment, or housing. We fit multivariate logistic regression models using generalized estimating equations to adjust for survey modality (online vs paper). Of participants, 41% (n = 143) reported experiences of transgender-related discrimination. Factors associated with transgender-related discrimination were geographic context, gender (female-to male spectrum vs male-to-female spectrum), low socioeconomic status, being a racial/ethnic minority, not having health insurance, gender transition indicators (younger age at first transgender awareness), health care needed but unable to be obtained (hormone therapy and mental health services), history of violence (sexual and physical), substance use health behaviors (tobacco and alcohol), and interpersonal factors (family support and community connectedness). Findings suggest that transgender Virginians experience widespread discrimination in health care, employment, and housing. Multilevel interventions are needed for transgender populations, including legal protections and training for health care providers.

Racial Discrimination, Ethnic-Racial Socialization, and Crime: A Micro-sociological Model of Risk and Resilience

PubMed Central

Burt, Callie Harbin; Simons, Ronald L.; Gibbons, Frederick X.

2013-01-01

Dominant theoretical explanations of racial disparities in criminal offending overlook a key risk factor associated with race: interpersonal racial discrimination. Building on recent studies that analyze race and crime at the micro-level, we specify a social psychological model linking personal experiences with racial discrimination to an increased risk of offending. We add to this model a consideration of an adaptive facet of African American culture: ethnic-racial socialization, and explore whether two forms—cultural socialization and preparation for bias—provide resilience to the criminogenic effects of interpersonal racial discrimination. Using panel data from several hundred African American male youth from the Family and Community Health Study, we find that racial discrimination is positively associated with increased crime in large part by augmenting depression, hostile views of relationships, and disengagement from conventional norms. Results also indicate that preparation for bias significantly reduces the effects of discrimination on crime, primarily by reducing the effects of these social psychological mediators on offending. Cultural socialization has a less influential but beneficial effect. Finally, we show that the more general parenting context within which preparation for bias takes place influences its protective effects. PMID:24058204

The role of socially prescribed perfectionism in the link between perceived racial discrimination and African American adolescents' depressive symptoms.

PubMed

Lambert, Sharon F; Robinson, W LaVome; Ialongo, Nicholas S

2014-05-01

Research examining the social origins of perfectionism has focused on negative evaluative experiences in the family, with less attention to negative social evaluations in other contexts and situations relevant for African American adolescents. The experience of racial discrimination is common for African American youth, and may trigger maladaptive perfectionistic beliefs if the youth perceive that they do not meet others' standards (socially prescribed perfectionism) or internalize discriminatory messages. Thus, the present study examined longitudinal associations among racial discrimination, socially prescribed perfectionism, and depressive symptoms among a community sample of urban and predominantly low income African American adolescents (n = 492; 46.7 % female). In each of grades 7, 8 and 9, participants reported their experiences with racial discrimination, perfectionistic beliefs, and depressive symptoms. Analyses revealed that experiences with racial discrimination in grade 7 were associated with socially prescribed perfectionism in grade 8 which, in turn, was linked with depressive symptoms in grade 9. Results suggest that prospective associations between the experience of racial discrimination and depressive symptoms are due, in part, to increased socially prescribed perfectionism. Implications for interventions targeting depression in African American are discussed.

The role of socially prescribed perfectionism in the link between perceived racial discrimination and African American adolescents’ depressive symptoms

PubMed Central

Lambert, Sharon F.; Robinson, W. LaVome; Ialongo, Nicholas S.

2013-01-01

Research examining the social origins of perfectionism has focused on negative evaluative experiences in the family, with less attention to negative social evaluations in other contexts and situations relevant for African American adolescents. The experience of racial discrimination is common for African American youth, and may trigger maladaptive perfectionistic beliefs if the youth perceive that they do not meet others’ standards (socially prescribed perfectionism) or internalize discriminatory messages. Thus, the present study examined longitudinal associations among racial discrimination, socially prescribed perfectionism, and depressive symptoms among a community sample of urban and predominantly low income African American adolescents (n = 492; 46.7% female). In each of grades 7, 8 and 9, participants reported their experiences with racial discrimination, perfectionistic beliefs, and depressive symptoms. Analyses revealed that experiences with racial discrimination in grade 7 were associated with socially prescribed perfectionism in grade 8 which, in turn, was linked with depressive symptoms in grade 9. Results suggest that prospective associations between the experience of racial discrimination and depressive symptoms are due, in part, to increased socially prescribed perfectionism. Implications for interventions targeting depression in African American are discussed. PMID:24150863

Characterizing chaotic melodies in automatic music composition

NASA Astrophysics Data System (ADS)

Coca, Andrés E.; Tost, Gerard O.; Zhao, Liang

2010-09-01

In this paper, we initially present an algorithm for automatic composition of melodies using chaotic dynamical systems. Afterward, we characterize chaotic music in a comprehensive way as comprising three perspectives: musical discrimination, dynamical influence on musical features, and musical perception. With respect to the first perspective, the coherence between generated chaotic melodies (continuous as well as discrete chaotic melodies) and a set of classical reference melodies is characterized by statistical descriptors and melodic measures. The significant differences among the three types of melodies are determined by discriminant analysis. Regarding the second perspective, the influence of dynamical features of chaotic attractors, e.g., Lyapunov exponent, Hurst coefficient, and correlation dimension, on melodic features is determined by canonical correlation analysis. The last perspective is related to perception of originality, complexity, and degree of melodiousness (Euler's gradus suavitatis) of chaotic and classical melodies by nonparametric statistical tests.

Aging and the perception of 3-D shape from dynamic patterns of binocular disparity.

PubMed

Norman, J Farley; Crabtree, Charles E; Herrmann, Molly; Thompson, Sarah R; Shular, Cassandra F; Clayton, Anna Marie

2006-01-01

In two experiments, we investigated the ability of younger and older observers to perceive and discriminate 3-D shape from static and dynamic patterns of binocular disparity. In both experiments, the younger observers' discrimination accuracies were 20% higher than those of the older observers. Despite this quantitative difference, in all other respects the older observers performed similarly to the younger observers. Both age groups were similarly affected by changes in the magnitude of binocular disparity, by reductions in binocular correspondence, and by increases in the speed of stereoscopic motion. In addition, observers in both age groups exhibited an advantage in performance for dynamic stereograms when the patterns of binocular disparity contained significant amounts of correspondence "noise." The process of aging does affect stereopsis, but the effects are quantitative rather than qualitative.

Subcortical Plasticity Following Perceptual Learning in a Pitch Discrimination Task

PubMed Central

Plack, Christopher J.

2010-01-01

Practice can lead to dramatic improvements in the discrimination of auditory stimuli. In this study, we investigated changes of the frequency-following response (FFR), a subcortical component of the auditory evoked potentials, after a period of pitch discrimination training. Twenty-seven adult listeners were trained for 10 h on a pitch discrimination task using one of three different complex tone stimuli. One had a static pitch contour, one had a rising pitch contour, and one had a falling pitch contour. Behavioral measures of pitch discrimination and FFRs for all the stimuli were measured before and after the training phase for these participants, as well as for an untrained control group (n = 12). Trained participants showed significant improvements in pitch discrimination compared to the control group for all three trained stimuli. These improvements were partly specific for stimuli with the same pitch modulation (dynamic vs. static) and with the same pitch trajectory (rising vs. falling) as the trained stimulus. Also, the robustness of FFR neural phase locking to the sound envelope increased significantly more in trained participants compared to the control group for the static and rising contour, but not for the falling contour. Changes in FFR strength were partly specific for stimuli with the same pitch modulation (dynamic vs. static) of the trained stimulus. Changes in FFR strength, however, were not specific for stimuli with the same pitch trajectory (rising vs. falling) as the trained stimulus. These findings indicate that even relatively low-level processes in the mature auditory system are subject to experience-related change. PMID:20878201

Subcortical plasticity following perceptual learning in a pitch discrimination task.

PubMed

Carcagno, Samuele; Plack, Christopher J

2011-02-01

Practice can lead to dramatic improvements in the discrimination of auditory stimuli. In this study, we investigated changes of the frequency-following response (FFR), a subcortical component of the auditory evoked potentials, after a period of pitch discrimination training. Twenty-seven adult listeners were trained for 10 h on a pitch discrimination task using one of three different complex tone stimuli. One had a static pitch contour, one had a rising pitch contour, and one had a falling pitch contour. Behavioral measures of pitch discrimination and FFRs for all the stimuli were measured before and after the training phase for these participants, as well as for an untrained control group (n = 12). Trained participants showed significant improvements in pitch discrimination compared to the control group for all three trained stimuli. These improvements were partly specific for stimuli with the same pitch modulation (dynamic vs. static) and with the same pitch trajectory (rising vs. falling) as the trained stimulus. Also, the robustness of FFR neural phase locking to the sound envelope increased significantly more in trained participants compared to the control group for the static and rising contour, but not for the falling contour. Changes in FFR strength were partly specific for stimuli with the same pitch modulation (dynamic vs. static) of the trained stimulus. Changes in FFR strength, however, were not specific for stimuli with the same pitch trajectory (rising vs. falling) as the trained stimulus. These findings indicate that even relatively low-level processes in the mature auditory system are subject to experience-related change.

Perceived Racial Discrimination and Negative-Mood–Related Drinking Among African American College Students

PubMed Central

O’hara, Ross E.; Armeli, Stephen; Scott, Denise M.; Covault, Jonathan; Tennen, Howard

2015-01-01

Objective: Research consistently shows a positive association between racial discrimination and problematic alcohol use among African Americans, but little is known about the micro-processes linking this pernicious form of stress to drinking. One possibility is that the cumulative effects of discrimination increase individuals’ likelihood of negative-mood–related drinking. In the current study, we examined whether individual differences in lifetime perceived racial discrimination among African American college students moderate relations between daily negative moods and evening alcohol consumption in both social and nonsocial contexts. Method: Data came from an online daily diary study of 441 African Americans (58% female) enrolled at a historically black college/university. Lifetime discrimination was measured at baseline. For 30 days, students reported the number of drinks they consumed the night before both socially and nonsocially, as well as their daytime level of negative mood. Results: In support of the hypotheses, only men who reported higher (vs. lower) lifetime discrimination showed a positive association between daily negative mood and that evening’s level of nonsocial drinking. Contrary to expectation, women who reported higher (vs. lower) discrimination showed a negative association between daily negative mood and nonsocial drinking. Neither daily negative mood nor lifetime discrimination predicted level of social drinking. Conclusions: These findings provide further evidence that the cumulative impact of racial discrimination may produce a vulnerability to negative-mood–related drinking—but only for African American men. Importantly, these effects emerged only for nonsocial drinking, which may further explain the robust association between discrimination and problematic alcohol use. PMID:25785798

Mexican Origin Youths’ Trajectories of Perceived Peer Discrimination from Middle Childhood to Adolescence: Variation by Neighborhood Ethnic Concentration

PubMed Central

White, Rebecca M. B.; Zeiders, Katharine H.; Knight, George P.; Roosa, Mark W.; Tein, Jenn-Yun

2014-01-01

Developmentally salient research on perceived peer discrimination among minority youths is limited. Little is known about trajectories of perceived peer discrimination across the developmental period ranging from middle childhood to adolescence. Ethically concentrated neighborhoods are hypothesized to protect minority youths from discrimination, but strong empirical tests are lacking. The first aim of the current study was to estimate trajectories of perceived peer discrimination from middle childhood to adolescence, as youths transitioned from elementary to middle and to high school. The second aim was to examine the relationship between neighborhood ethnic concentration and perceived peer discrimination over time. Using a diverse sample of 749 Mexican origin youths (48.9% female), a series of growth models revealed that youths born in Mexico, relative to those born in the U.S., perceived higher discrimination in the 5th grade and decreases across time. Youths who had higher averages on neighborhood ethnic concentration (across the developmental period) experienced decreases in perceived peer discrimination over time; those that had lower average neighborhood ethnic concentration levels showed evidence of increasing trajectories. Further, when individuals experienced increases in their own neighborhood ethnic concentration levels (relative to their own cross-time averages), they reported lower levels of perceived peer discrimination. Neighborhood ethnic concentration findings were not explained by the concurrent changes youths were experiencing in school ethnic concentrations. The results support a culturally-informed developmental view of perceived peer discrimination that recognizes variability in co-ethnic neighborhood contexts. The results advance a view of ethnic enclaves as protective from mainstream threats. PMID:24488094

Do spouses matter? Discrimination, social support, and psychological distress among Asian Americans.

PubMed

Rollock, David; Lui, P Priscilla

2016-01-01

Perceived discrimination poses risks for psychological distress among Asian Americans, but the differential impact of general unfair treatment and racial discrimination has not been examined. Although social support from distal sources reduces discrimination-related distress either directly or as a buffer, the unique roles of spousal support have remained understudied. Nativity status was examined as another moderator of these relationships to resolve previous inconsistent findings regarding its relationship to the discrimination-distress link. Data were from 1,626 U.S.- and foreign-born Asian American adults (Mage = 42.17 years; n = 1,142 married/cohabiting) in the nationally representative National Latino and Asian American Study, who reported on experiences of unfair treatment, racial discrimination, social supports from spouses, family, friends, and neighborhood, and psychological distress. Hierarchical multiple regressions showed that both unfair treatment and racial discrimination predicted psychological distress, and spousal support predicted distress above and beyond distal forms of social support in the context of perceived discrimination. Moderation analyses revealed that spousal support buffered against negative psychological consequences of unfair treatment, but not racial discrimination. Spousal support was not differentially protective as a function of nativity; however, U.S.-born respondents reacted with greater distress to unfair treatment than their foreign-born counterparts. Psychological effects of both general and race-based discrimination, and the unique contributions of distinct sources of social support, are important to understanding adjustment and cultural transition among Asian Americans. Nativity differentially influences effects of unfair treatment. Implications for future research are discussed. (c) 2016 APA, all rights reserved).

Mexican origin youths' trajectories of perceived peer discrimination from middle childhood to adolescence: variation by neighborhood ethnic concentration.

PubMed

White, Rebecca M B; Zeiders, Katharine H; Knight, George P; Roosa, Mark W; Tein, Jenn-Yun

2014-10-01

Developmentally salient research on perceived peer discrimination among minority youths is limited. Little is known about trajectories of perceived peer discrimination across the developmental period ranging from middle childhood to adolescence. Ethically concentrated neighborhoods are hypothesized to protect minority youths from discrimination, but strong empirical tests are lacking. The first aim of the current study was to estimate trajectories of perceived peer discrimination from middle childhood to adolescence, as youths transitioned from elementary to middle and to high school. The second aim was to examine the relationship between neighborhood ethnic concentration and perceived peer discrimination over time. Using a diverse sample of 749 Mexican origin youths (48.9% female), a series of growth models revealed that youths born in Mexico, relative to those born in the U.S., perceived higher discrimination in the 5th grade and decreases across time. Youths who had higher averages on neighborhood ethnic concentration (across the developmental period) experienced decreases in perceived peer discrimination over time; those that had lower average neighborhood ethnic concentration levels showed evidence of increasing trajectories. Further, when individuals experienced increases in their own neighborhood ethnic concentration levels (relative to their own cross-time averages), they reported lower levels of perceived peer discrimination. Neighborhood ethnic concentration findings were not explained by the concurrent changes youths were experiencing in school ethnic concentrations. The results support a culturally-informed developmental view of perceived peer discrimination that recognizes variability in co-ethnic neighborhood contexts. The results advance a view of ethnic enclaves as protective from mainstream threats.

Discrimination and common mental disorder among migrant and ethnic groups: findings from a South East London Community sample.

PubMed

Hatch, S L; Gazard, B; Williams, D R; Frissa, S; Goodwin, L; Hotopf, M

2016-05-01

Few studies have examined discrimination and mental health in the UK, particularly by migrant status and in urban contexts with greater demographic diversity. This study aims to (1) describe the prevalence of discrimination experiences across multiple life domains; (2) to describe associations between discrimination experiences and common mental disorder (CMD); (3) to determine whether or not the relationship between discrimination and CMD varies by migrant status and ethnicity. Data on major, anticipated and everyday discrimination and CMD symptoms were collected from an ethnically diverse prospective sample of 1052 participants followed up from 2008 to 2013 in the South East London Community Health study, a population-based household survey. With few exceptions, discrimination was most prevalent among those in the Black Caribbean group. However, those in the White Other ethnic group had similar or greater reporting major and anticipated discrimination to Black or mixed ethnic minority groups. The effects of discrimination on CMD were most pronounced for individuals who had recently migrated to the UK, an ethnically heterogeneous group, and for Black and Mixed ethnic minority groups in partially adjusted models. Prior CMD accounted for differences between the Mixed and White British ethnic groups, but the strength of the association for the most recent migrant group and the Black ethnic groups remained two or more times greater than the reference groups. The strength of the relationship suggests a need for more consideration of migration status along with ethnicity in examining the impact of discrimination on mental disorder in community and clinical samples.

Associations Between Multiple Forms of Discrimination and Tobacco Use Among People Living With HIV: The Mediating Role of Avoidance Coping.

PubMed

Crockett, Kaylee B; Rice, Whitney S; Turan, Bulent

2018-05-01

People living with HIV (PLWH) have higher levels of tobacco use compared with the general population, increasing their risk of morbidity and mortality. PLWH also face potential chronic stressors related to the stigma and discrimination associated with HIV and other characteristics (eg, race and sexual orientation). These experiences may be associated with harmful health behaviors, such as tobacco use. The purpose of the current study is to explore the psychosocial context of tobacco use in PLWH, examining avoidance coping as a mediator in the relationship between multiple forms of discrimination and tobacco use. Participants included 202 PLWH recruited from an HIV primary care clinic in Birmingham, AL, between 2013 and 2015. Participants responded to parallel items assessing experiences of discrimination related to HIV status, race, and sexual orientation, as well as items assessing avoidance coping. Data on current tobacco use were obtained from participants' clinic records. Mediation models for each form of discrimination (HIV, race and sexual orientation) adjusting for demographic variables and the other forms of discrimination were evaluated. The indirect effect of HIV-related discrimination on likelihood of tobacco use through avoidance coping was significant, suggesting that avoidance coping mediates the association between HIV-related discrimination and tobacco use. However, the indirect effects of the other forms of discrimination were not significant. Given the disparity in tobacco use in PLWH, behavioral scientists and interventionists should consider including content specific to coping with experiences of discrimination in tobacco prevention and cessation programs for PLWH.

A discrimination index for selecting markers of tumor growth dynamic across multiple cancer studies with a cure fraction.

PubMed

Rouam, Sigrid; Broët, Philippe

2013-08-01

To identify genomic markers with consistent effect on tumor dynamics across multiple cancer series, discrimination indices based on proportional hazards models can be used since they do not depend heavily on the sample size. However, the underlying assumption of proportionality of the hazards does not always hold, especially when the studied population is a mixture of cured and uncured patients, like in early-stage cancers. We propose a novel index that quantifies the capability of a genomic marker to separate uncured patients, according to their time-to-event outcomes. It allows to identify genomic markers characterizing tumor growth dynamic across multiple studies. Simulation results show that our index performs better than classical indices based on the Cox model. It is neither affected by the sample size nor the cure rate fraction. In a cross-study of early-stage breast cancers, the index allows to select genomic markers with a potential consistent effect on tumor growth dynamics. Copyright © 2013 Elsevier Inc. All rights reserved.

Contextualizing immigrants' lived experience: story of Taiwanese immigrants in the United States.

PubMed

Tsai, Jenny Hsin-Chun

2003-01-01

Immigration involves extensive changes in living environments. Nonetheless, the predominant approach in the health science literature has been to utilize individual characteristics (including ethnic background) to explain and predict immigrants' lived experiences and health outcomes. Contexts, particularly the larger societal contexts by which immigrants are constituted, are generally ignored. Data from a critical ethnography regarding immigrants' experiences with language, occupation, and economic survival in the United States are utilized to illustrate that immigrants' lives are inseparable from the larger societal contexts, such as immigration policy, Western imperialism, and structural discrimination. The implications for practice, education, and research are discussed.

Same-sex marriage and context-specific kinship terms.

PubMed

Ould, Patricia; Whitlow, C Julie

2011-01-01

This study investigates whether married gays and lesbians in Massachusetts are using the kinship terms commonly associated with marriage in referring to and introducing their marriage partners and, if not, whether alternative terms are being used in a variety of social contexts. We demonstrate through survey and interview data that marriage-related terms are used discriminately, are consciously chosen, and are context specific. Choices are dependent on a variety of factors related to personal demographics, speech community associations, intimacy, identity, and safety. A significant difference in the use of terms after legal marriage has occurred suggesting a shift in attitude.

Do dimensions of ethnic identity mediate the association between perceived ethnic group discrimination and depressive symptoms?

PubMed

Brittian, Aerika S; Kim, Su Yeong; Armenta, Brian E; Lee, Richard M; Umaña-Taylor, Adriana J; Schwartz, Seth J; Villalta, Ian K; Zamboanga, Byron L; Weisskirch, Robert S; Juang, Linda P; Castillo, Linda G; Hudson, Monika L

2015-01-01

Ethnic group discrimination represents a notable risk factor that may contribute to mental health problems among ethnic minority college students. However, cultural resources (e.g., ethnic identity) may promote psychological adjustment in the context of group-based discriminatory experiences. In the current study, we examined the associations between perceptions of ethnic group discrimination and depressive symptoms, and explored dimensions of ethnic identity (i.e., exploration, resolution, and affirmation) as mediators of this process among 2,315 ethnic minority college students (age 18 to 30 years; 37% Black, 63% Latino). Results indicated that perceived ethnic group discrimination was associated positively with depressive symptoms among students from both ethnic groups. The relationship between perceived ethnic group discrimination and depressive symptoms was mediated by ethnic identity affirmation for Latino students, but not for Black students. Ethnic identity resolution was negatively and indirectly associated with depressive symptoms through ethnic identity affirmation for both Black and Latino students. Implications for promoting ethnic minority college students' mental health and directions for future research are discussed. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

"The Only Thing I Wish I Could Change Is That They Treat Us Like People and Not Like Animals": Injury and Discrimination Among Latino Farmworkers.

PubMed

Snipes, Shedra A; Cooper, Sharon P; Shipp, Eva M

2017-01-01

This article describes how perceived discrimination shapes the way Latino farmworkers encounter injuries and seek out treatment. After 5 months of ethnographic fieldwork, 89 open-ended, semistructured interviews were analyzed. NVivo was used to code and qualitatively organize the interviews and field notes. Finally, codes, notes, and co-occurring dynamics were used to iteratively assess the data for major themes. The primary source of perceived discrimination was the "boss" or farm owner. Immigrant status was also a significant influence on how farmworkers perceived the discrimination. Specifically, the ability to speak English and length of stay in the United States were related to stronger perceptions of discrimination. Finally, farm owners compelled their Latino employees to work through their injuries without treatment. This ethnographic account brings attention to how discrimination and lack of worksite protections are implicated in farmworkers' injury experiences and suggests the need for policies that better safeguard vulnerable workers.

Perceived discrimination among Latino immigrants in new destinations: The case of Durham, NC1

PubMed Central

Flippen, Chenoa A.; Parrado, Emilio A.

2015-01-01

This paper draws on original survey data to assess the prevalence of perceived discrimination among Latin American immigrants to Durham, NC, a “new immigrant destinations” in the Southeastern United States. Even though discrimination has a wide-ranging impact on social groups, from blocked opportunities, to adverse health outcomes, to highlighting and reifying inter-group boundaries, research among immigrant Latinos is rare, especially in new destinations. Our theoretical framework and empirical analysis expand social constructivist approaches that view ethnic discrimination as emerging from processes of competition and incorporation. We broaden prior discussions by investigating the specific social forces that give rise to perceived discrimination. In particular, we examine the extent to which perceptions of unequal treatment vary by gender, elaborating on the situational conditions than differentiate discrimination experiences for men and women. We also incorporate dimensions unique to the contemporary Latino immigrant experience, such as legal status, family migration dynamics, and transnationalism. PMID:26848208

Developmental improvements in the resolution and capacity of visual working memory share a common source

PubMed Central

Simmering, Vanessa R.; Miller, Hilary E.

2016-01-01

The nature of visual working memory (VWM) representations is currently a source of debate between characterizations as slot-like versus a flexibly-divided pool of resources. Recently, a dynamic neural field model has been proposed as an alternative account that focuses more on the processes by which VWM representations are formed, maintained, and used in service of behavior. This dynamic model has explained developmental increases in VWM capacity and resolution through strengthening excitatory and inhibitory connections. Simulations of developmental improvements in VWM resolution suggest that one important change is the accuracy of comparisons between items held in memory and new inputs. Thus, the ability to detect changes is a critical component of developmental improvements in VWM performance across tasks, leading to the prediction that capacity and resolution should correlate during childhood. Comparing 5- to 8-year-old children’s performance across color discrimination and change detection tasks revealed the predicted correlation between estimates of VWM capacity and resolution, supporting the hypothesis that increasing connectivity underlies improvements in VWM during childhood. These results demonstrate the importance of formalizing the processes that support the use of VWM, rather than focusing solely on the nature of representations. We conclude by considering our results in the broader context of VWM development. PMID:27329264

Divergence in male cricket song and female preference functions in three allopatric sister species.

PubMed

Hennig, Ralf Matthias; Blankers, Thomas; Gray, David A

2016-05-01

Multivariate female preference functions for male sexual signals have rarely been investigated, especially in a comparative context among sister species. Here we examined male signal and female preference co-variation in three closely related, but allopatric species of Gryllus crickets and quantified male song traits as well as female preferences. We show that males differ conspicuously in either one of two relatively static song traits, carrier frequency or pulse rate; female preference functions for these traits also differed, and would in combination enhance species discrimination. In contrast, the relatively dynamic song traits, chirp rate and chirp duty cycle, show minimal divergence among species and relatively greater conservation of female preference functions. Notably, among species we demonstrate similar mechanistic rules for the integration of pulse and chirp time scales, despite divergence in pulse rate preferences. As these are allopatric taxa, selection for species recognition per se is unlikely. More likely sexual selection combined with conserved properties of preference filters enabled divergent coevolution of male song and female preferences.

[The psychovegetative disorders as an ego-structural problem].

PubMed

Ermann, M

1982-01-01

The personality structure of patients suffering from psychovegetative disorders is described in the present article from aspects of the psychology of the ego. The focus of all such disorders is a defective desomatization of affectations and the functions of perception. In proportion to the extent of the developmental disorder this specific pathology of the ego is either employed regressively in the defense of conflicts or serves for the release of a structurally strongly limited ego. More precise investigation of the ego structure leads to the descrimination between vegetative neuroses as limited ego pathology on the one hand and psychovegetative disorders in the context of a more extensive ego pathology, as they occur in borderline syndromes or serious narcissistic disorders of the personality on the other. Diagnostically the discrimination may be made by considering the patients own description of their complaints and the structure of their characters, by evaluating the quality of anxiety and affectations, and on the basis of the dynamics of the psychotherapeutic relationship. Consequently there are characteristic differences for the course of treatment.

Limiting Energy Dissipation Induces Glassy Kinetics in Single-Cell High-Precision Responses.

PubMed

Das, Jayajit

2016-03-08

Single cells often generate precise responses by involving dissipative out-of-thermodynamic-equilibrium processes in signaling networks. The available free energy to fuel these processes could become limited depending on the metabolic state of an individual cell. How does limiting dissipation affect the kinetics of high-precision responses in single cells? I address this question in the context of a kinetic proofreading scheme used in a simple model of early-time T cell signaling. Using exact analytical calculations and numerical simulations, I show that limiting dissipation qualitatively changes the kinetics in single cells marked by emergence of slow kinetics, large cell-to-cell variations of copy numbers, temporally correlated stochastic events (dynamic facilitation), and ergodicity breaking. Thus, constraints in energy dissipation, in addition to negatively affecting ligand discrimination in T cells, can create a fundamental difficulty in determining single-cell kinetics from cell-population results. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

RACE AS LIVED EXPERIENCE

PubMed Central

Garcia, John A.; Sanchez, Gabriel R.; Sanchez-Youngman, Shannon; Vargas, Edward D.; Ybarra, Vickie D.

2015-01-01

A growing body of social science research has sought to conceptualize race as a multidimensional concept in which context, societal relations, and institutional dynamics are key components. Utilizing a specially designed survey, we develop and use multiple measures of race (skin color, ascribed race, and discrimination experiences) to capture race as “lived experience” and assess their impact on Latinos’ self-rated health status. We model these measures of race as a lived experience to test the explanatory power of race, both independently and as an integrated scale with categorical regression, scaling, and dimensional analyses. Our analyses show that our multiple measures of race have significant and negative effects on Latinos’ self-reported health. Skin color is a dominant factor that impacts self-reported health both directly and indirectly. We then advocate for the utilization of multiple measures of race, adding to those used in our analysis, and their application to other health and social outcomes. Our analysis provides important contributions across a wide range of health, illness, social, and political outcomes for communities of color. PMID:26681972

The Importance of Segregation, Discrimination, Peer Dynamics, and Identity in Explaining Trends in the Racial Achievement Gap. NBER Working Paper No. 16257

ERIC Educational Resources Information Center

Fryer, Roland G., Jr.

2010-01-01

After decades of narrowing, the achievement gap between black and white school children widened in the 1990s--a period when the labor market rewards for education were increasing. This presents an important puzzle for economists. In this chapter, I investigate the extent to which economic models of segregation, information-based discrimination,…

Excitotoxic lesions of the infralimbic, but not prelimbic cortex facilitate reversal of appetitive discriminative context conditioning: the role of the infralimbic cortex in context generalization

PubMed Central

Ashwell, Rachel; Ito, Rutsuko

2014-01-01

The prelimbic and infralimbic regions of the rat medial prefrontal cortex (mPFC) are important components of the limbic cortico-striatal circuit, receiving converging projections from the hippocampus (HPC) and amygdala. Mounting evidence points to these regions having opposing roles in the regulation of the expression of contextual fear and context-induced cocaine-seeking. To investigate this functional differentiation in motivated behavior further, this study employed a novel radial maze task previously shown to be dependent on the integrity of the hippocampus and its functional connection to the nucleus accumbens (NAc) shell, to investigate the effects of selective excitotoxic lesions of the prelimbic (PL) and infralimbic (IL) upon the spatial contextual control over reward learning. To this end, rats were trained to develop discriminative responding towards a reward-associated discrete cue presented in three out of six spatial locations (3 arms out of 6 radial maze arms), and to avoid the same discrete cue presented in the other three spatial locations. Once acquired, the reward contingencies of the spatial locations were reversed, such that responding to the cue presented in a previously rewarded location was no longer rewarded. Furthermore, the acquisition of spatial learning was probed separately using conditioned place preference (CPP) and the monitoring of arm selection at the beginning of each training session. Lesions of the PL transiently attenuated the acquisition of the initial cue approach training and spatial learning, while leaving reversal learning intact. In contrast, IL lesions led to a significantly superior performance of spatial context-dependent discriminative cue approach and reversal learning, in the absence of a significant preference for the new reward-associated spatial locations. These results indicate that the PL and IL have functionally dissociative, and potentially opposite roles in the regulation of spatial contextual control over appetitive learning. PMID:24616678

Studying primate learning in group contexts: Tests of social foraging, response to novelty, and cooperative problem solving.

PubMed

Drea, Christine M

2006-03-01

Learning commonly refers to the modification of behavior through experience, whereby an animal gains information about stimulus-response contingencies from interacting with its physical environment. Social learning, on the other hand, occurs when the same information originates, not from the animal's personal experience, but from the actions of others. Socially biased learning is the 'collective outcome of interacting physical, social, and individual factors' [D. Fragaszy, E. Visalberghi, Learn. Behav. 32 (2004) 24-35.] (see p. 24). Mounting interest in animal social learning has brought with it certain innovations in animal testing procedures. Variants of the observer-demonstrator and cooperation paradigms, for instance, have been used widely in captive settings to examine the transmission or coordination of behavior, respectively, between two animals. Relatively few studies, however, have examined social learning in more complex group settings and even fewer have manipulated the social environment to empirically test the effect of group dynamics on problem solving. The present paper outlines procedures for group testing captive non-human primates, in spacious arenas, to evaluate the social modulation of learning and performance. These methods are illustrated in the context of (1) naturalistic social foraging problems, modeled after traditional visual discrimination paradigms, (2) response to novel objects and novel extractive foraging tasks, and (3) cooperative problem solving. Each example showcases the benefits of experimentally manipulating social context to compare an animal's performance in intact groups (or even pairs) against its performance under different social circumstances. Broader application of group testing procedures and manipulation of group composition promise to provide meaningful insight into socially biased learning.

Context effects in a temporal discrimination task" further tests of the Scalar Expectancy Theory and Learning-to-Time models.

PubMed

Arantes, Joana; Machado, Armando

2008-07-01

Pigeons were trained on two temporal bisection tasks, which alternated every two sessions. In the first task, they learned to choose a red key after a 1-s signal and a green key after a 4-s signal; in the second task, they learned to choose a blue key after a 4-s signal and a yellow key after a 16-s signal. Then the pigeons were exposed to a series of test trials in order to contrast two timing models, Learning-to-Time (LeT) and Scalar Expectancy Theory (SET). The models made substantially different predictions particularly for the test trials in which the sample duration ranged from 1 s to 16 s and the choice keys were Green and Blue, the keys associated with the same 4-s samples: LeT predicted that preference for Green should increase with sample duration, a context effect, but SET predicted that preference for Green should not vary with sample duration. The results were consistent with LeT. The present study adds to the literature the finding that the context effect occurs even when the two basic discriminations are never combined in the same session.

Revisiting the role of language in spatial cognition: Categorical perception of spatial relations in English and Korean speakers.

PubMed

Holmes, Kevin J; Moty, Kelsey; Regier, Terry

2017-12-01

The spatial relation of support has been regarded as universally privileged in nonlinguistic cognition and immune to the influence of language. English, but not Korean, obligatorily distinguishes support from nonsupport via basic spatial terms. Despite this linguistic difference, previous research suggests that English and Korean speakers show comparable nonlinguistic sensitivity to the support/nonsupport distinction. Here, using a paradigm previously found to elicit cross-language differences in color discrimination, we provide evidence for a difference in sensitivity to support/nonsupport between native English speakers and native Korean speakers who were late English learners and tested in a context that privileged Korean. Whereas the former group showed categorical perception (CP) when discriminating spatial scenes capturing the support/nonsupport distinction, the latter did not. An additional group of native Korean speakers-relatively early English learners tested in an English-salient context-patterned with the native English speakers in showing CP for support/nonsupport. These findings suggest that obligatory marking of support/nonsupport in one's native language can affect nonlinguistic sensitivity to this distinction, contra earlier findings, but that such sensitivity may also depend on aspects of language background and the immediate linguistic context.

Learning context modulates aversive taste strength in honey bees.

PubMed

de Brito Sanchez, Maria Gabriela; Serre, Marion; Avarguès-Weber, Aurore; Dyer, Adrian G; Giurfa, Martin

2015-03-01

The capacity of honey bees (Apis mellifera) to detect bitter substances is controversial because they ingest without reluctance different kinds of bitter solutions in the laboratory, whereas free-flying bees avoid them in visual discrimination tasks. Here, we asked whether the gustatory perception of bees changes with the behavioral context so that tastes that are less effective as negative reinforcements in a given context become more effective in a different context. We trained bees to discriminate an odorant paired with 1 mol l(-1) sucrose solution from another odorant paired with either distilled water, 3 mol l(-1) NaCl or 60 mmol l(-1) quinine. Training was either Pavlovian [olfactory conditioning of the proboscis extension reflex (PER) in harnessed bees], or mainly operant (olfactory conditioning of free-walking bees in a Y-maze). PER-trained and maze-trained bees were subsequently tested both in their original context and in the alternative context. Whereas PER-trained bees transferred their choice to the Y-maze situation, Y-maze-trained bees did not respond with a PER to odors when subsequently harnessed. In both conditioning protocols, NaCl and distilled water were the strongest and the weakest aversive reinforcement, respectively. A significant variation was found for quinine, which had an intermediate aversive effect in PER conditioning but a more powerful effect in the Y-maze, similar to that of NaCl. These results thus show that the aversive strength of quinine varies with the learning context, and reveal the plasticity of the bee's gustatory system. We discuss the experimental constraints of both learning contexts and focus on stress as a key modulator of taste in the honey bee. Further explorations of bee taste are proposed to understand the physiology of taste modulation in bees. © 2015. Published by The Company of Biologists Ltd.

Recombinative Generalization: An Exploratory Study in Musical Reading

PubMed Central

Perez, William Ferreira; de Rose, Julio C

2010-01-01

The present study aimed to extend the findings of recombinative generalization research in alphabetical reading and spelling to the context of musical reading. One participant was taught to respond discriminatively to six two-note sequences, choosing the corresponding notation on the staff in the presence of each sequence. When novel three- and four-note sequences were presented, she selected the corresponding notation. These results suggest the generality of previous research to the context of musical teaching. PMID:22477462

Context-Aware Local Binary Feature Learning for Face Recognition.

PubMed

Duan, Yueqi; Lu, Jiwen; Feng, Jianjiang; Zhou, Jie

2018-05-01

In this paper, we propose a context-aware local binary feature learning (CA-LBFL) method for face recognition. Unlike existing learning-based local face descriptors such as discriminant face descriptor (DFD) and compact binary face descriptor (CBFD) which learn each feature code individually, our CA-LBFL exploits the contextual information of adjacent bits by constraining the number of shifts from different binary bits, so that more robust information can be exploited for face representation. Given a face image, we first extract pixel difference vectors (PDV) in local patches, and learn a discriminative mapping in an unsupervised manner to project each pixel difference vector into a context-aware binary vector. Then, we perform clustering on the learned binary codes to construct a codebook, and extract a histogram feature for each face image with the learned codebook as the final representation. In order to exploit local information from different scales, we propose a context-aware local binary multi-scale feature learning (CA-LBMFL) method to jointly learn multiple projection matrices for face representation. To make the proposed methods applicable for heterogeneous face recognition, we present a coupled CA-LBFL (C-CA-LBFL) method and a coupled CA-LBMFL (C-CA-LBMFL) method to reduce the modality gap of corresponding heterogeneous faces in the feature level, respectively. Extensive experimental results on four widely used face datasets clearly show that our methods outperform most state-of-the-art face descriptors.

Contextual effects on preattentive processing of sound motion as revealed by spatial MMN.

PubMed

Shestopalova, L B; Petropavlovskaia, E A; Vaitulevich, S Ph; Nikitin, N I

2015-04-01

The magnitude of spatial distance between sound stimuli is critically important for their preattentive discrimination, yet the effect of stimulus context on auditory motion processing is not clear. This study investigated the effects of acoustical change and stimulus context on preattentive spatial change detection. Auditory event-related potentials (ERPs) were recorded for stationary midline noises and two patterns of sound motion produced by linear or abrupt changes of interaural time differences. Each of the three types of stimuli was used as standard or deviant in different blocks. Context effects on mismatch negativity (MMN) elicited by stationary and moving sound stimuli were investigated by reversing the role of standard and deviant stimuli, while the acoustical stimulus parameters were kept the same. That is, MMN amplitudes were calculated by subtracting ERPs to identical stimuli presented as standard in one block and deviant in another block. In contrast, effects of acoustical change on MMN amplitudes were calculated by subtracting ERPs of standards and deviants presented within the same block. Preattentive discrimination of moving and stationary sounds indexed by MMN was strongly dependent on the stimulus context. Higher MMNs were produced in oddball configurations where deviance represented increments of the sound velocity, as compared to configurations with velocity decrements. The effect of standard-deviant reversal was more pronounced with the abrupt sound displacement than with gradual sound motion. Copyright © 2015 Elsevier B.V. All rights reserved.

Engagement with genetic discrimination: concerns and experiences in the context of Huntington disease

PubMed Central

Bombard, Yvonne; Penziner, Elizabeth; Suchowersky, Oksana; Guttman, Mark; Paulsen, Jane S; Bottorff, Joan L; Hayden, Michael R

2013-01-01

It has been over 20 years since the inception of predictive testing for Huntington disease (HD), yet the social implications of knowing one's genetic risk for HD have not been fully explored. Genetic discrimination (GD) is a potential risk associated with predictive testing. Although anecdotal reports of GD have been documented, there is a paucity of research on the nature and experiences of GD in the context of HD. The purpose of this study was to describe the concerns and experiences of GD in the HD community. Semistructured interviews were conducted with 45 genetically tested and 10 untested individuals and analyzed using grounded theory methods. Our findings demonstrate that a majority of individuals were concerned about (37/55) and experienced GD (32/55) across a variety of contexts that extend beyond the traditionally examined contexts of insurance and employment to include family, social, government, and health-care domains. We describe a process of engagement with GD in which individuals formed meaningful interpretations of GD and personalized its risk and consequences in their lives. Our findings provide an insight into some of the specific processes and factors influencing engagement with GD. These results help identify areas where more education and support is needed and provide direction to genetic professionals supporting their clients as they confront issues of GD and genetic testing. PMID:17957229

Effects of D-cycloserine on the extinction of appetitive operant learning

PubMed Central

Vurbic, Drina; Gold, Benjamin; Bouton, Mark E.

2011-01-01

Four experiments with rat subjects examined whether D-cycloserine (DCS), a partial NMDA agonist, facilitates the extinction of operant lever-pressing reinforced by food. Previous research has demonstrated that DCS facilitates extinction learning with methods that involve Pavlovian extinction. In the current experiments, operant conditioning occurred in Context A, extinction in Context B, and then testing occurred in both the extinction and conditioning contexts. Experiments 1a and 1b tested the effects of three doses of DCS (5, 15, and 30 mg/kg) on the extinction of lever pressing trained as a free operant. Experiment 2 examined their effects when extinction of the free operant was conducted in the presence of non-response-contingent deliveries of the reinforcer (which theoretically reduced the role of generalization decrement in suppressing responding). Experiment 3 examined their effects on extinction of a discriminated operant, i.e., one that had been reinforced in the presence of a discriminative stimulus, but not in its absence. A strong ABA renewal effect was observed in all four experiments during testing. However, despite the use of DCS doses and a drug administration procedure that facilitates the extinction of Pavlovian learning, there was no evidence in any experiment that DCS facilitated operant extinction learning assessed in either the extinction or the conditioning context. DCS may primarily facilitate learning processes that underlie Pavlovian, rather than purely operant, extinction. PMID:21688894

Semi-supervised learning for ordinal Kernel Discriminant Analysis.

PubMed

Pérez-Ortiz, M; Gutiérrez, P A; Carbonero-Ruz, M; Hervás-Martínez, C

2016-12-01

Ordinal classification considers those classification problems where the labels of the variable to predict follow a given order. Naturally, labelled data is scarce or difficult to obtain in this type of problems because, in many cases, ordinal labels are given by a user or expert (e.g. in recommendation systems). Firstly, this paper develops a new strategy for ordinal classification where both labelled and unlabelled data are used in the model construction step (a scheme which is referred to as semi-supervised learning). More specifically, the ordinal version of kernel discriminant learning is extended for this setting considering the neighbourhood information of unlabelled data, which is proposed to be computed in the feature space induced by the kernel function. Secondly, a new method for semi-supervised kernel learning is devised in the context of ordinal classification, which is combined with our developed classification strategy to optimise the kernel parameters. The experiments conducted compare 6 different approaches for semi-supervised learning in the context of ordinal classification in a battery of 30 datasets, showing (1) the good synergy of the ordinal version of discriminant analysis and the use of unlabelled data and (2) the advantage of computing distances in the feature space induced by the kernel function. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of dynamical models: dissipative synchronization and other techniques.

PubMed

Aguirre, Luis Antonio; Furtado, Edgar Campos; Tôrres, Leonardo A B

2006-12-01

Some recent developments for the validation of nonlinear models built from data are reviewed. Besides giving an overall view of the field, a procedure is proposed and investigated based on the concept of dissipative synchronization between the data and the model, which is very useful in validating models that should reproduce dominant dynamical features, like bifurcations, of the original system. In order to assess the discriminating power of the procedure, four well-known benchmarks have been used: namely, Duffing-Ueda, Duffing-Holmes, and van der Pol oscillators, plus the Hénon map. The procedure, developed for discrete-time systems, is focused on the dynamical properties of the model, rather than on statistical issues. For all the systems investigated, it is shown that the discriminating power of the procedure is similar to that of bifurcation diagrams--which in turn is much greater than, say, that of correlation dimension--but at a much lower computational cost.

Dopamine controls the neural dynamics of memory signals and retrieval accuracy.

PubMed

Apitz, Thore; Bunzeck, Nico

2013-11-01

The human brain is capable of differentiating between new and already stored information rapidly to allow optimal behavior and decision-making. Although the neural mechanisms of novelty discrimination were often described as temporally constant (ie, with specific latencies), recent electrophysiological studies have demonstrated that the onset of neural novelty signals (ie, differences in event-related responses to new and old items) can be accelerated by reward motivation. While the precise physiological mechanisms underlying this acceleration remain unclear, the involvement of the neurotransmitter dopamine in both novelty and reward processing suggests that enhanced dopamine levels in the context of reward prospect may have a role. To investigate this hypothesis, we used magnetoencephalography (MEG) in combination with an old/new recognition memory task in which correct discrimination between old and new items was rewarded. Importantly, before the task, human subjects received either 150 mg of the dopamine precursor levodopa or placebo. For the placebo group, old/new signals peaked at ∼100 ms after stimulus onset over left temporal/occipital sensors. In contrast, after levodopa administration earliest old/new effects only emerged after ∼400 ms and retrieval accuracy was reduced as expressed in lower d' values. As such, our results point towards a previously unreported role of dopamine in controlling the chronometry of neural processes underlying the distinction between old and new information. They also suggest that this relationship follows a nonlinear function whereby slightly enhanced dopamine levels accelerate neural/cognitive processes and excessive dopamine levels impair them.

The mediating effect of self-esteem on the relationship between perceived discrimination and psychological well-being in immigrants.

PubMed

Urzúa, Alfonso; Ferrer, Rodrigo; Godoy, Nidia; Leppes, Francisca; Trujillo, Carlos; Osorio, Camila; Caqueo-Urízar, Alejandra

2018-01-01

The aim of the study is to analyze the mediating effect of self-esteem on the relationship between perceived discrimination and psychological well-being in South American immigrants in Chile. An analytical, cross sectional, non-experimental design was used. We evaluated 853 Peruvians and Colombians living in the northern cities of Arica, Antofagasta, and Santiago de Chile, the capital located in the center of the country. The instruments used were the Ryff Psychological Well-being Scale, the Rosenberg Self-Esteem Scale and the Perceived Discrimination Scale by Basabe, Paez, Aierdi and Jiménez-Aristizabal. We used the estimation method (RWLS) and polychoric correlation matrices, to estimate the effect size and overall fit of the direct effect models of discrimination and self-esteem on psychological well-being, and indirect and total effects of discrimination mediated by self-esteem. While both populations reported similar levels of perceived discrimination, it was found that the means in psychological well-being and self-esteem of the Colombian population were significantly higher than that of the Peruvian population. Regarding self-esteem, the results provided evidence for the possible mediating effect on the relationship between perceived discrimination and psychological well-being. This research aims to contribute to the development of interventions seeking to strengthen self-esteem in order to circumvent possible negative consequences of perceived discrimination, as a consequent, improving immigrants´ personal resources to successfully cope with the diverse demands of their new context.

Health consequences of racist and antigay discrimination for multiple minority adolescents.

PubMed

Thoma, Brian C; Huebner, David M

2013-10-01

Individuals who belong to a marginalized group and who perceive discrimination based on that group membership suffer from a variety of poor health outcomes. Many people belong to more than one marginalized group, and much less is known about the influence of multiple forms of discrimination on health outcomes. Drawing on literature describing the influence of multiple stressors, three models of combined forms of discrimination are discussed: additive, prominence, and exacerbation. The current study examined the influence of multiple forms of discrimination in a sample of African American lesbian, gay, or bisexual (LGB) adolescents ages 14-19. Each of the three models of combined stressors were tested to determine which best describes how racist and antigay discrimination combine to predict depressive symptoms, suicidal ideation, and substance use. Participants were included in this analysis if they identified their ethnicity as either African American (n = 156) or African American mixed (n = 120). Mean age was 17.45 years (SD = 1.36). Results revealed both forms of mistreatment were associated with depressive symptoms and suicidal ideation among African American LGB adolescents. Racism was more strongly associated with substance use. Future intervention efforts should be targeted toward reducing discrimination and improving the social context of multiple minority adolescents, and future research with multiple minority individuals should be attuned to the multiple forms of discrimination experienced by these individuals within their environments. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Dynamic clustering detection through multi-valued descriptors of dermoscopic images.

PubMed

Cozza, Valentina; Guarracino, Maria Rosario; Maddalena, Lucia; Baroni, Adone

2011-09-10

This paper introduces a dynamic clustering methodology based on multi-valued descriptors of dermoscopic images. The main idea is to support medical diagnosis to decide if pigmented skin lesions belonging to an uncertain set are nearer to malignant melanoma or to benign nevi. Melanoma is the most deadly skin cancer, and early diagnosis is a current challenge for clinicians. Most data analysis algorithms for skin lesions discrimination focus on segmentation and extraction of features of categorical or numerical type. As an alternative approach, this paper introduces two new concepts: first, it considers multi-valued data that scalar variables not only describe but also intervals or histogram variables; second, it introduces a dynamic clustering method based on Wasserstein distance to compare multi-valued data. The overall strategy of analysis can be summarized into the following steps: first, a segmentation of dermoscopic images allows to identify a set of multi-valued descriptors; second, we performed a discriminant analysis on a set of images where there is an a priori classification so that it is possible to detect which features discriminate the benign and malignant lesions; and third, we performed the proposed dynamic clustering method on the uncertain cases, which need to be associated to one of the two previously mentioned groups. Results based on clinical data show that the grading of specific descriptors associated to dermoscopic characteristics provides a novel way to characterize uncertain lesions that can help the dermatologist's diagnosis. Copyright © 2011 John Wiley & Sons, Ltd.

Legal Protections in Public Accommodations Settings: A Critical Public Health Issue for Transgender and Gender-Nonconforming People

PubMed Central

Reisner, Sari L; Hughto, Jaclyn M White; Dunham, Emilia E; Heflin, Katherine J; Begenyi, Jesse Blue Glass; Coffey-Esquivel, Julia; Cahill, Sean

2015-01-01

Context Gender minority people who are transgender or gender nonconforming experience widespread discrimination and health inequities. Since 2012, Massachusetts law has provided protections against discrimination on the basis of gender identity in employment, housing, credit, public education, and hate crimes. The law does not, however, protect against discrimination in public accommodations (eg, hospitals, health centers, transportation, nursing homes, supermarkets, retail establishments). For this article, we examined the frequency and health correlates of public accommodations discrimination among gender minority adults in Massachusetts, with attention to discrimination in health care settings. Methods In 2013, we recruited a community-based sample (n = 452) both online and in person. The respondents completed a 1-time, electronic survey assessing demographics, health, health care utilization, and discrimination in public accommodations venues in the past 12 months. Using adjusted multivariable logistic regression models, we examined whether experiencing public accommodations discrimination in health care was independently associated with adverse self-reported health, adjusting for discrimination in other public accommodations settings. Findings Overall, 65% of respondents reported public accommodations discrimination in the past 12 months. The 5 most prevalent discrimination settings were transportation (36%), retail (28%), restaurants (26%), public gatherings (25%), and health care (24%). Public accommodations discrimination in the past 12 months in health care settings was independently associated with a 31% to 81% increased risk of adverse emotional and physical symptoms and a 2-fold to 3-fold increased risk of postponement of needed care when sick or injured and of preventive or routine health care, adjusting for discrimination in other public accommodations settings (which also conferred an additional 20% to 77% risk per discrimination setting endorsed). Conclusions Discrimination in public accommodations is common and is associated with adverse health outcomes among transgender and gender-nonconforming adults in Massachusetts. Discrimination in health care settings creates a unique health risk for gender minority people. The passage and enforcement of transgender rights laws that include protections against discrimination in public accommodations—inclusive of health care—are a public health policy approach critically needed to address transgender health inequities. PMID:26219197

Perceived Racial/Ethnic Discrimination and Mental Health: a Review and Future Directions for Social Epidemiology

PubMed Central

Vines, Anissa I.; Ward, Julia B.; Cordoba, Evette; Black, Kristin Z.

2017-01-01

Purpose of review Recent literature on racial or ethnic discrimination and mental health was reviewed to assess the current science and identify key areas of emphasis for social epidemiology. Objectives of this review were to: 1) Determine whether there have been advancements in the measurement and analysis of perceived discrimination; 2) Identify the use of theories and/or frameworks in perceived discrimination and mental health research; and 3) Assess the extent to which stress buffers are being considered and evaluated in the existing literature. Recent findings Metrics and analytic approaches used to assess discrimination remain largely unchanged. Theory and/or frameworks such as the stress and coping framework continue to be underused in majority of the studies. Adolescents and young adults experiencing racial/ethnic discrimination were at greater risk of adverse mental health outcomes, and the accumulation of stressors over the life course may have an aggregate impact on mental health. Some growth seems evident in studies examining the mediation and moderation of stress buffers and other key factors with the findings suggesting a reduction in the effects of discrimination on mental health. Summary Discrimination scales should consider the multiple social identities of a person, the context where the exposure occurs, how the stressor manifests specifically in adolescents, the historical traumas, and cumulative exposure. Life course theory and intersectionality may help guide future work. Despite existing research, gaps remain in in elucidating the effects of racial and ethnic discrimination on mental health, signaling an opportunity and a call to social epidemiologists to engage in interdisciplinary research to speed research progress. PMID:28920011

Perceived Racial/Ethnic Discrimination and Mental Health: a Review and Future Directions for Social Epidemiology.

PubMed

Vines, Anissa I; Ward, Julia B; Cordoba, Evette; Black, Kristin Z

2017-06-01

Recent literature on racial or ethnic discrimination and mental health was reviewed to assess the current science and identify key areas of emphasis for social epidemiology. Objectives of this review were to: 1) Determine whether there have been advancements in the measurement and analysis of perceived discrimination; 2) Identify the use of theories and/or frameworks in perceived discrimination and mental health research; and 3) Assess the extent to which stress buffers are being considered and evaluated in the existing literature. Metrics and analytic approaches used to assess discrimination remain largely unchanged. Theory and/or frameworks such as the stress and coping framework continue to be underused in majority of the studies. Adolescents and young adults experiencing racial/ethnic discrimination were at greater risk of adverse mental health outcomes, and the accumulation of stressors over the life course may have an aggregate impact on mental health. Some growth seems evident in studies examining the mediation and moderation of stress buffers and other key factors with the findings suggesting a reduction in the effects of discrimination on mental health. Discrimination scales should consider the multiple social identities of a person, the context where the exposure occurs, how the stressor manifests specifically in adolescents, the historical traumas, and cumulative exposure. Life course theory and intersectionality may help guide future work. Despite existing research, gaps remain in in elucidating the effects of racial and ethnic discrimination on mental health, signaling an opportunity and a call to social epidemiologists to engage in interdisciplinary research to speed research progress.

Predictive Coding in Area V4: Dynamic Shape Discrimination under Partial Occlusion

PubMed Central

Choi, Hannah; Pasupathy, Anitha; Shea-Brown, Eric

2018-01-01

The primate visual system has an exquisite ability to discriminate partially occluded shapes. Recent electrophysiological recordings suggest that response dynamics in intermediate visual cortical area V4, shaped by feedback from prefrontal cortex (PFC), may play a key role. To probe the algorithms that may underlie these findings, we build and test a model of V4 and PFC interactions based on a hierarchical predictive coding framework. We propose that probabilistic inference occurs in two steps. Initially, V4 responses are driven solely by bottom-up sensory input and are thus strongly influenced by the level of occlusion. After a delay, V4 responses combine both feedforward input and feedback signals from the PFC; the latter reflect predictions made by PFC about the visual stimulus underlying V4 activity. We find that this model captures key features of V4 and PFC dynamics observed in experiments. Specifically, PFC responses are strongest for occluded stimuli and delayed responses in V4 are less sensitive to occlusion, supporting our hypothesis that the feedback signals from PFC underlie robust discrimination of occluded shapes. Thus, our study proposes that area V4 and PFC participate in hierarchical inference, with feedback signals encoding top-down predictions about occluded shapes. PMID:29566355

Rapid Decision-Making with Side-Specific Perceptual Discrimination in Ants

PubMed Central

Stroeymeyt, Nathalie; Guerrieri, Fernando J.; van Zweden, Jelle S.; d'Ettorre, Patrizia

2010-01-01

Background Timely decision making is crucial for survival and reproduction. Organisms often face a speed-accuracy trade-off, as fully informed, accurate decisions require time-consuming gathering and treatment of information. Optimal strategies for decision-making should therefore vary depending on the context. In mammals, there is mounting evidence that multiple systems of perceptual discrimination based on different neural circuits emphasize either fast responses or accurate treatment of stimuli depending on the context. Methodology/Principal Findings We used the ant Camponotus aethiops to test the prediction that fast information processing achieved through direct neural pathways should be favored in situations where quick reactions are adaptive. Social insects discriminate readily between harmless group-members and dangerous strangers using easily accessible cuticular hydrocarbons as nestmate recognition cues. We show that i) tethered ants display rapid aggressive reactions upon presentation of non-nestmate odor (120 to 160 ms); ii) ants' aggressiveness towards non-nestmates can be specifically reduced by exposure to non-nestmate odor only, showing that social interactions are not required to alter responses towards non-nestmates; iii) decision-making by ants does not require information transfer between brain hemispheres, but relies on side-specific decision rules. Conclusions/Significance Our results strongly suggest that first-order olfactory processing centers (up to the antennal lobes) are likely to play a key role in ant nestmate recognition. We hypothesize that the coarse level of discrimination achieved in the antennal lobes early in odor processing provides enough information to determine appropriate behavioral responses towards non-nestmates. This asks for a reappraisal of the mechanisms underlying social recognition in insects. PMID:20808782

Sex differences in conditioned stimulus discrimination during context-dependent fear learning and its retrieval in humans: the role of biological sex, contraceptives and menstrual cycle phases.

PubMed

Lonsdorf, Tina B; Haaker, Jan; Schümann, Dirk; Sommer, Tobias; Bayer, Janine; Brassen, Stefanie; Bunzeck, Nico; Gamer, Matthias; Kalisch, Raffael

2015-11-01

Anxiety disorders are more prevalent in women than in men. Despite this sexual dimorphism, most experimental studies are conducted in male participants and studies focusing on sex differences are sparse. In addition, the role of hormonal contraceptives and menstrual cycle phase in fear conditioning and extinction processes remain largely unknown. We investigated sex differences in context-dependent fear acquisition and extinction (day 1) and their retrieval/expression (day 2). Skin conductance responses (SCRs), fear and unconditioned stimulus expectancy ratings were obtained. We included 377 individuals (261 women) in our study. Robust sex differences were observed in all dependent measures. Women generally displayed higher subjective ratings but smaller SCRs than men and showed reduced excitatory/inhibitory conditioned stimulus (CS+/CS-) discrimination in all dependent measures. Furthermore, women using hormonal contraceptives showed reduced SCR CS discrimination on day 2 than men and free-cycling women, while menstrual cycle phase had no effect. Possible limitations include the simultaneous testing of up to 4 participants in cubicles, which might have introduced a social component, and not assessing postexperimental contingency awareness. The response pattern in women shows striking similarity to previously reported sex differences in patients with anxiety. Our results suggest that pronounced deficits in associative discrimination learning and subjective expression of safety information (CS- responses) might underlie higher prevalence and higher symptom rates seen in women with anxiety disorders. The data call for consideration of biological sex and hormonal contraceptive use in future studies and may suggest that targeting inhibitory learning during therapy might aid precision medicine.

Visual discrimination transfer and modulation by biogenic amines in honeybees.

PubMed

Vieira, Amanda Rodrigues; Salles, Nayara; Borges, Marco; Mota, Theo

2018-05-10

For more than a century, visual learning and memory have been studied in the honeybee Apis mellifera using operant appetitive conditioning. Although honeybees show impressive visual learning capacities in this well-established protocol, operant training of free-flying animals cannot be combined with invasive protocols for studying the neurobiological basis of visual learning. In view of this, different attempts have been made to develop new classical conditioning protocols for studying visual learning in harnessed honeybees, though learning performance remains considerably poorer than that for free-flying animals. Here, we investigated the ability of honeybees to use visual information acquired during classical conditioning in a new operant context. We performed differential visual conditioning of the proboscis extension reflex (PER) followed by visual orientation tests in a Y-maze. Classical conditioning and Y-maze retention tests were performed using the same pair of perceptually isoluminant chromatic stimuli, to avoid the influence of phototaxis during free-flying orientation. Visual discrimination transfer was clearly observed, with pre-trained honeybees significantly orienting their flights towards the former positive conditioned stimulus (CS+), thus showing that visual memories acquired by honeybees are resistant to context changes between conditioning and the retention test. We combined this visual discrimination approach with selective pharmacological injections to evaluate the effect of dopamine and octopamine in appetitive visual learning. Both octopaminergic and dopaminergic antagonists impaired visual discrimination performance, suggesting that both these biogenic amines modulate appetitive visual learning in honeybees. Our study brings new insight into cognitive and neurobiological mechanisms underlying visual learning in honeybees. © 2018. Published by The Company of Biologists Ltd.

Ants detect but do not discriminate diseased workers within their nest

NASA Astrophysics Data System (ADS)

Leclerc, Jean-Baptiste; Detrain, Claire

2016-08-01

Social insects have evolved an array of individual and social behaviours that limit pathogen entrance and spread within the colony. The detection of ectoparasites or of fungal spores on a nestmate body triggers their removal by allogrooming and appears as a primary component of social prophylaxis. However, in the case of fungal infection, one may wonder whether ant workers are able to detect, discriminate and keep at bay diseased nestmates that have no spores over their cuticle but which constitute a latent sanitary risk due to post-mortem corpse sporulation. Here, we investigate the ability of Myrmica rubra workers to detect and discriminate a healthy from a diseased nestmate infected by the entomopathogen Metarhizium anisopliae. During dyadic encounters in a neutral location, workers were more aggressive towards isolated sick nestmates on the 3rd post-infection day. However, no such detection or discrimination of fungus-infected nestmates occurred in a social context inside the nest or at the nest entrance. Gatekeepers never actively rejected incoming diseased nestmates that rather spontaneously isolated themselves outside the nest. Our study reveals that ant workers may detect health-dependent cues and that their `acceptance level' of sick nestmates is tunable depending on the social context. This raises questions about possible trade-offs between a social closure to pathogens and risks of erroneous rejection of healthy nestmates. Social isolation of moribund ants also appears as a widespread prophylactic strategy of social insects allowing them to reduce exposure to pathogens and to spare costs associated with the management of infected individuals.

Neuronal pattern separation of motion-relevant input in LIP activity

PubMed Central

Berberian, Nareg; MacPherson, Amanda; Giraud, Eloïse; Richardson, Lydia

2016-01-01

In various regions of the brain, neurons discriminate sensory stimuli by decreasing the similarity between ambiguous input patterns. Here, we examine whether this process of pattern separation may drive the rapid discrimination of visual motion stimuli in the lateral intraparietal area (LIP). Starting with a simple mean-rate population model that captures neuronal activity in LIP, we show that overlapping input patterns can be reformatted dynamically to give rise to separated patterns of neuronal activity. The population model predicts that a key ingredient of pattern separation is the presence of heterogeneity in the response of individual units. Furthermore, the model proposes that pattern separation relies on heterogeneity in the temporal dynamics of neural activity and not merely in the mean firing rates of individual neurons over time. We confirm these predictions in recordings of macaque LIP neurons and show that the accuracy of pattern separation is a strong predictor of behavioral performance. Overall, results propose that LIP relies on neuronal pattern separation to facilitate decision-relevant discrimination of sensory stimuli. NEW & NOTEWORTHY A new hypothesis is proposed on the role of the lateral intraparietal (LIP) region of cortex during rapid decision making. This hypothesis suggests that LIP alters the representation of ambiguous inputs to reduce their overlap, thus improving sensory discrimination. A combination of computational modeling, theoretical analysis, and electrophysiological data shows that the pattern separation hypothesis links neural activity to behavior and offers novel predictions on the role of LIP during sensory discrimination. PMID:27881719

Pattern vision of the honeybee (Apis mellifera): blue and green receptors in the discrimination of translocation.

PubMed

Horridge, A

2000-07-01

The visual discrimination of horizontal gratings by the honeybee (Apis mellifera) was studied in a Y-choice apparatus with fixed patterns presented vertically at a set range. Translocation in this context is the exchange of the positions of two different colored or black areas. This paper investigates what cues the bees have learned in this task. The patterns, made from combinations of calibrated colored papers, are designed to explore the parts played by the blue and green receptors when the boundary between the two colors provides contrast to only one receptor type. Horizontal translocation is not discriminated without contrast to the green receptors, but up/down translocation can be discriminated whatever the contrast at the boundary. The trained bees were tested on the same patterns made with different papers that included extreme changes in contrast. The results show that discrimination of up/down translocation involves green receptors and also blue receptors. When bees discriminate a translocation that shows contrast to only one type of receptor, they do not use the apparent brightness or the direction of the contrast to that receptor type acting alone. Instead, they discriminate the locations of colored areas irrespective of intensity differences or directions of contrasts. They use some measure of the photon flux at both receptor types and remember the difference between the colors and their locations. Copyright 2000 Academic Press.

The association between discrimination and depressive symptoms among older African Americans: the role of psychological and social factors.

PubMed

Nadimpalli, Sarah B; James, Bryan D; Yu, Lei; Cothran, Fawn; Barnes, Lisa L

2015-01-01

BACKGROUND/STUDY CONTEXT: Several studies have demonstrated a link between perceived discrimination and depression in ethnic minority groups, yet most have focused on younger or middle-aged African Americans and little is known about factors that may moderate the relationship. Participants were 487 older African Americans (60-98 years old) enrolled in the Minority Aging Research Study. Discrimination, depressive symptoms, and psychological and social resources were assessed via interview using validated measures. Ordinal logistic regression models were used to assess (1) the main relationship between discrimination and depression and (2) resilience, purpose in life, social isolation, and social networks as potential moderators of this relationship. In models adjusted for age, sex, education, and income, perceived discrimination was positively associated with depressive symptoms (odds ratio [OR]: 1.20, 95% confidence interval [CI]: 1.10-1.31; p < .001). However, there was no evidence of effect modification by resilience, purpose in life, social isolation, or social networks (all ps ≤ .05). Findings provide support for accumulating evidence on the adverse mental health effects of discrimination among older African Americans. Because the association was not modified by psychological or social factors, these findings do not support a role for a buffering effect of resources on discrimination and depressive symptoms. Further studies are needed to examine a wider range of coping resources among older adults.

Can honey bees discriminate between floral-fragrance isomers?

PubMed

Aguiar, João Marcelo Robazzi Bignelli Valente; Roselino, Ana Carolina; Sazima, Marlies; Giurfa, Martin

2018-05-24

Many flowering plants present variable complex fragrances, which usually include different isomers of the same molecule. As fragrance is an essential cue for flower recognition by pollinators, we ask if honey bees discriminate between floral-fragrance isomers in an appetitive context. We used the olfactory conditioning of the proboscis extension response (PER), which allows training a restrained bee to an odor paired with sucrose solution. Bees were trained under an absolute (a single odorant rewarded) or a differential conditioning regime (a rewarded vs. a non-rewarded odorant) using four different pairs of isomers. One hour after training, discrimination and generalization between pairs of isomers were tested. Bees trained under absolute conditioning exhibited high generalization between isomers and discriminated only one out of four isomer pairs; after differential conditioning, they learned to differentiate between two out of four pairs of isomers but in all cases generalization responses to the non-rewarding isomer remained high. Adding an aversive taste to the non-rewarded isomer facilitated discrimination of isomers that otherwise seemed non-discriminable, but generalization remained high. Although honey bees discriminated isomers under certain conditions, they achieved the task with difficulty and tended to generalize between them, thus showing that these molecules were perceptually similar to them. We conclude that the presence of isomers within floral fragrances might not necessarily contribute to a dramatic extent to floral odor diversity. © 2018. Published by The Company of Biologists Ltd.

Exploring Discrimination and Mental Health Disparities Faced By Black Sexual Minority Women Using a Minority Stress Framework

PubMed Central

Calabrese, Sarah K.; Meyer, Ilan H.; Overstreet, Nicole M.; Haile, Rahwa; Hansen, Nathan B.

2015-01-01

Black sexual minority women are triply marginalized due to their race, gender, and sexual orientation. We compared three dimensions of discrimination—frequency (regularity of occurrences), scope (number of types of discriminatory acts experienced), and number of bases (number of social statuses to which discrimination was attributed)—and self-reported mental health (depressive symptoms, psychological well-being, and social well-being) between 64 Black sexual minority women and each of two groups sharing two of three marginalized statuses: (a) 67 White sexual minority women and (b) 67 Black sexual minority men. Black sexual minority women reported greater discrimination frequency, scope, and number of bases and poorer psychological and social well-being than White sexual minority women and more discrimination bases, a higher level of depressive symptoms, and poorer social well-being than Black sexual minority men. We then tested and contrasted dimensions of discrimination as mediators between social status (race or gender) and mental health outcomes. Discrimination frequency and scope mediated the association between race and mental health, with a stronger effect via frequency among sexual minority women. Number of discrimination bases mediated the association between gender and mental health among Black sexual minorities. Future research and clinical practice would benefit from considering Black sexual minority women's mental health in a multidimensional minority stress context. PMID:26424904

The discrimination of geoforensic trace material from close proximity locations by organic profiling using HPLC and plant wax marker analysis by GC.

PubMed

McCulloch, G; Dawson, L A; Ross, J M; Morgan, R M

2018-07-01

There is a need to develop a wider empirical research base to expand the scope for utilising the organic fraction of soil in forensic geoscience, and to demonstrate the capability of the analytical techniques used in forensic geoscience to discriminate samples at close proximity locations. The determination of wax markers from soil samples by GC analysis has been used extensively in court and is known to be effective in discriminating samples from different land use types. A new HPLC method for the analysis of the organic fraction of forensic sediment samples has also been shown recently to add value in conjunction with existing inorganic techniques for the discrimination of samples derived from close proximity locations. This study compares the ability of these two organic techniques to discriminate samples derived from close proximity locations and finds the GC technique to provide good discrimination at this scale, providing quantification of known compounds, whilst the HPLC technique offered a shorter and simpler sample preparation method and provided very good discrimination between groups of samples of different provenance in most cases. The use of both data sets together gave further improved accuracy rates in some cases, suggesting that a combined organic approach can provide added benefits in certain case scenarios and crime reconstruction contexts. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Assessment of variation in the alberta context tool: the contribution of unit level contextual factors and specialty in Canadian pediatric acute care settings

PubMed Central

2011-01-01

Background There are few validated measures of organizational context and none that we located are parsimonious and address modifiable characteristics of context. The Alberta Context Tool (ACT) was developed to meet this need. The instrument assesses 8 dimensions of context, which comprise 10 concepts. The purpose of this paper is to report evidence to further the validity argument for ACT. The specific objectives of this paper are to: (1) examine the extent to which the 10 ACT concepts discriminate between patient care units and (2) identify variables that significantly contribute to between-unit variation for each of the 10 concepts. Methods 859 professional nurses (844 valid responses) working in medical, surgical and critical care units of 8 Canadian pediatric hospitals completed the ACT. A random intercept, fixed effects hierarchical linear modeling (HLM) strategy was used to quantify and explain variance in the 10 ACT concepts to establish the ACT's ability to discriminate between units. We ran 40 models (a series of 4 models for each of the 10 concepts) in which we systematically assessed the unique contribution (i.e., error variance reduction) of different variables to between-unit variation. First, we constructed a null model in which we quantified the variance overall, in each of the concepts. Then we controlled for the contribution of individual level variables (Model 1). In Model 2, we assessed the contribution of practice specialty (medical, surgical, critical care) to variation since it was central to construction of the sampling frame for the study. Finally, we assessed the contribution of additional unit level variables (Model 3). Results The null model (unadjusted baseline HLM model) established that there was significant variation between units in each of the 10 ACT concepts (i.e., discrimination between units). When we controlled for individual characteristics, significant variation in the 10 concepts remained. Assessment of the contribution of specialty to between-unit variation enabled us to explain more variance (1.19% to 16.73%) in 6 of the 10 ACT concepts. Finally, when we assessed the unique contribution of the unit level variables available to us, we were able to explain additional variance (15.91% to 73.25%) in 7 of the 10 ACT concepts. Conclusion The findings reported here represent the third published argument for validity of the ACT and adds to the evidence supporting its use to discriminate patient care units by all 10 contextual factors. We found evidence of relationships between a variety of individual and unit-level variables that explained much of this between-unit variation for each of the 10 ACT concepts. Future research will include examination of the relationships between the ACT's contextual factors and research utilization by nurses and ultimately the relationships between context, research utilization, and outcomes for patients. PMID:21970404

Global trends on fears and concerns of genetic discrimination: a systematic literature review.

PubMed

Wauters, Annet; Van Hoyweghen, Ine

2016-04-01

Since the 1990s, developments in the field of genetics have led to many questions on the use and possible misuse of genetic information. 'Genetic discrimination' has been defined as the differential treatment of asymptomatic individuals or their relatives on the basis of their real or assumed genetic characteristics. Despite the public policy attention around genetic discrimination, there is currently still much confusion surrounding this phenomenon. On the one hand, there is little evidence of the occurrence of genetic discrimination. On the other hand, it appears that people remain concerned about this theme, and this fear influences their health and life choices. This article makes use of a systematic literature review to investigate what is already known about the nature, extent and background of these fears and concerns. The 42 included studies have found considerable levels of concerns about genetic discrimination. Concerns dominate in insurance contexts and within personal interactions. The extent of concerns appears to vary depending on the type of genetic illness. Furthermore, installed laws prohibiting genetic discrimination do not seem to alleviate existing fears. This raises important questions as to the origins of these fears. Based on the findings, recommendations for future research are made. First, research on the background of fears is needed. Second, future research needs to assess more fully all different forms (for example, direct and indirect) of genetic discrimination. Thirdly, it has to be studied whether genetic discrimination is a form of discrimination that is distinguishable from discrimination based on an illness or disability. Finally, a last element that should be addressed in future research is the most recent developments in research on genomics, such as next-generation sequencing or genome-wide association studies.

Optimal design of stimulus experiments for robust discrimination of biochemical reaction networks.

PubMed

Flassig, R J; Sundmacher, K

2012-12-01

Biochemical reaction networks in the form of coupled ordinary differential equations (ODEs) provide a powerful modeling tool for understanding the dynamics of biochemical processes. During the early phase of modeling, scientists have to deal with a large pool of competing nonlinear models. At this point, discrimination experiments can be designed and conducted to obtain optimal data for selecting the most plausible model. Since biological ODE models have widely distributed parameters due to, e.g. biologic variability or experimental variations, model responses become distributed. Therefore, a robust optimal experimental design (OED) for model discrimination can be used to discriminate models based on their response probability distribution functions (PDFs). In this work, we present an optimal control-based methodology for designing optimal stimulus experiments aimed at robust model discrimination. For estimating the time-varying model response PDF, which results from the nonlinear propagation of the parameter PDF under the ODE dynamics, we suggest using the sigma-point approach. Using the model overlap (expected likelihood) as a robust discrimination criterion to measure dissimilarities between expected model response PDFs, we benchmark the proposed nonlinear design approach against linearization with respect to prediction accuracy and design quality for two nonlinear biological reaction networks. As shown, the sigma-point outperforms the linearization approach in the case of widely distributed parameter sets and/or existing multiple steady states. Since the sigma-point approach scales linearly with the number of model parameter, it can be applied to large systems for robust experimental planning. An implementation of the method in MATLAB/AMPL is available at http://www.uni-magdeburg.de/ivt/svt/person/rf/roed.html. flassig@mpi-magdeburg.mpg.de Supplementary data are are available at Bioinformatics online.

Sex differences in audiovisual discrimination learning by Bengalese finches (Lonchura striata var. domestica).

PubMed

Seki, Yoshimasa; Okanoya, Kazuo

2008-02-01

Both visual and auditory information are important for songbirds, especially in developmental and sexual contexts. To investigate bimodal cognition in songbirds, the authors conducted audiovisual discrimination training in Bengalese finches. The authors used two types of stimulus: an "artificial stimulus," which is a combination of simple figures and sound, and a "biological stimulus," consisting of video images of singing males along with their songs. The authors found that while both sexes predominantly used visual cues in the discrimination tasks, males tended to be more dependent on auditory information for the biological stimulus. Female responses were always dependent on the visual stimulus for both stimulus types. Only males changed their discrimination strategy according to stimulus type. Although males used both visual and auditory cues for the biological stimulus, they responded to the artificial stimulus depending only on visual information, as the females did. These findings suggest a sex difference in innate auditory sensitivity. (c) 2008 APA.

[Mental health implications of workplace discrimination against sexual and gender minorities: A literature review].

PubMed

Geoffroy, Marie; Chamberland, Line

Despite legislative advances in terms of workplace equality for sexual and gender minorities (SGM), available data ascertains the persistence of workplace discrimination of lesbian, gay, bisexual, and especially of transgender/transsexual employees. This article, based on an extensive literature review, explores the relationship between different types of workplace discrimination experiences and their impacts on the mental health of SGM and of different sub-populations: men who have sex with men, non-heterosexual women, lesbian and gay parents, and trans people. Furthermore, the article explores certain individual and systemic protection and risk factors that have an impact on this relationship, such as coming-out at work and organisational support. Finally, the existing literature on workplace discrimination and mental health of sexual and gender minorities highlights the importance, in the current legal and social context, of intersectional approaches and of research on homo- and trans-negative microaggressions. The article ends with a discussion on the implications for practice, research, and workplace settings, as well as with several recommendations for these settings.

The Development of Face Perception in Infancy: Intersensory Interference and Unimodal Visual Facilitation

PubMed Central

Bahrick, Lorraine E.; Lickliter, Robert; Castellanos, Irina

2014-01-01

Although research has demonstrated impressive face perception skills of young infants, little attention has focused on conditions that enhance versus impair infant face perception. The present studies tested the prediction, generated from the Intersensory Redundancy Hypothesis (IRH), that face discrimination, which relies on detection of visual featural information, would be impaired in the context of intersensory redundancy provided by audiovisual speech, and enhanced in the absence of intersensory redundancy (unimodal visual and asynchronous audiovisual speech) in early development. Later in development, following improvements in attention, faces should be discriminated in both redundant audiovisual and nonredundant stimulation. Results supported these predictions. Two-month-old infants discriminated a novel face in unimodal visual and asynchronous audiovisual speech but not in synchronous audiovisual speech. By 3 months, face discrimination was evident even during synchronous audiovisual speech. These findings indicate that infant face perception is enhanced and emerges developmentally earlier following unimodal visual than synchronous audiovisual exposure and that intersensory redundancy generated by naturalistic audiovisual speech can interfere with face processing. PMID:23244407

Behavioral Assessment of Emotion Discrimination, Emotion Regulation, and Cognitive Control in Childhood, Adolescence, and Adulthood

PubMed Central

Tottenham, Nim; Hare, Todd A.; Casey, B. J.

2011-01-01

Emotion discrimination, emotion regulation, and cognitive control are three related, yet separable processes that emerge over the course of development. The current study tested 100 children, adolescents, and adults on an Emotional Go/Nogo task, illustrating the ability of this paradigm to identify the unique developmental patterns for each of these three processes in the context of both positive (happy) and negative emotions (fear, sad, and anger), across three different age groups. Consistent with previous literature, our findings show that emotion discrimination and regulatory abilities (both cognitive control and emotion regulation) improve steadily for each age group, with each age group showing unique patterns of performance. The findings suggest that emotion regulation is constructed from basic cognition control and emotion discrimination skills. The patterns of behavior from the Emotional Go/Nogo task provide normative benchmark data across a wide range of emotions that can be used for future behavioral and neuroimaging studies that examine the developmental construction of emotion regulatory processes. PMID:21716604

Modeling of the plasma extraction efficiency of an inductively coupled plasma-mass spectrometer interface using the direct simulation Monte Carlo method

NASA Astrophysics Data System (ADS)

Kivel, Niko; Potthast, Heiko-Dirk; Günther-Leopold, Ines; Vanhaecke, Frank; Günther, Detlef

The interface between the atmospheric pressure plasma ion source and the high vacuum mass spectrometer is a crucial part of an inductively coupled plasma-mass spectrometer. It influences the efficiency of the mass transfer into the mass spectrometer, it also contributes to the formation of interfering ions and to mass discrimination. This region was simulated using the Direct Simulation Monte Carlo method with respect to the formation of shock waves, mass transport and mass discrimination. The modeling results for shock waves and mass transport are in overall agreement with the literature. Insights into the effects and geometrical features causing mass discrimination could be gained. The overall observed collision based mass discrimination is lower than expected from measurements on real instruments, supporting the assumptions that inter-particle collisions play a minor role in this context published earlier. A full representation of the study, for two selected geometries, is given in form of a movie as supplementary data.

The analysis of colored acrylic, cotton, and wool textile fibers using micro-Raman spectroscopy. Part 2: comparison with the traditional methods of fiber examination.

PubMed

Buzzini, Patrick; Massonnet, Genevieve

2015-05-01

In the second part of this survey, the ability of micro-Raman spectroscopy to discriminate 180 fiber samples of blue, black, and red cottons, wools, and acrylics was compared to that gathered with the traditional methods for the examination of textile fibers in a forensic context (including light microscopy methods, UV-vis microspectrophotometry and thin-layer chromatography). This study shows that the Raman technique plays a complementary and useful role to obtain further discriminations after the application of light microscopy methods and UV-vis microspectrophotometry and assure the nondestructive nature of the analytical sequence. These additional discriminations were observed despite the lower discriminating powers of Raman data considered individually, compared to those of light microscopy and UV-vis MSP. This study also confirms that an instrument equipped with several laser lines is necessary for an efficient use as applied to the examination of textile fibers in a forensic setting. © 2015 American Academy of Forensic Sciences.

No evidence for visual context-dependency of olfactory learning in Drosophila

NASA Astrophysics Data System (ADS)

Yarali, Ayse; Mayerle, Moritz; Nawroth, Christian; Gerber, Bertram

2008-08-01

How is behaviour organised across sensory modalities? Specifically, we ask concerning the fruit fly Drosophila melanogaster how visual context affects olfactory learning and recall and whether information about visual context is getting integrated into olfactory memory. We find that changing visual context between training and test does not deteriorate olfactory memory scores, suggesting that these olfactory memories can drive behaviour despite a mismatch of visual context between training and test. Rather, both the establishment and the recall of olfactory memory are generally facilitated by light. In a follow-up experiment, we find no evidence for learning about combinations of odours and visual context as predictors for reinforcement even after explicit training in a so-called biconditional discrimination task. Thus, a ‘true’ interaction between visual and olfactory modalities is not evident; instead, light seems to influence olfactory learning and recall unspecifically, for example by altering motor activity, alertness or olfactory acuity.

Social Salience Discriminates Learnability of Contextual Cues in an Artificial Language.

PubMed

Rácz, Péter; Hay, Jennifer B; Pierrehumbert, Janet B

2017-01-01

We investigate the learning of contextual meaning by adults in an artificial language. Contextual meaning here refers to the non-denotative contextual information that speakers attach to a linguistic construction. Through a series of short games, played online, we test how well adults can learn different contextual meanings for a word-formation pattern in an artificial language. We look at whether learning contextual meanings depends on the social salience of the context, whether our players interpret these contexts generally, and whether the learned meaning is generalized to new words. Our results show that adults are capable of learning contextual meaning if the context is socially salient, coherent, and interpretable. Once a contextual meaning is recognized, it is readily generalized to related forms and contexts.

Individual variability in visual discrimination and reversal learning performance in common marmosets.

PubMed

Takemoto, Atsushi; Miwa, Miki; Koba, Reiko; Yamaguchi, Chieko; Suzuki, Hiromi; Nakamura, Katsuki

2015-04-01

Detailed information about the characteristics of learning behavior in marmosets is useful for future marmoset research. We trained 42 marmosets in visual discrimination and reversal learning. All marmosets could learn visual discrimination, and all but one could complete reversal learning, though some marmosets failed to touch the visual stimuli and were screened out. In 87% of measurements, the final percentage of correct responses was over 95%. We quantified performance with two measures: onset trial and dynamic interval. Onset trial represents the number of trials that elapsed before the marmoset started to learn. Dynamic interval represents the number of trials from the start before reaching the final percentage of correct responses. Both measures decreased drastically as a result of the formation of discrimination learning sets. In reversal learning, both measures worsened, but the effect on onset trial was far greater. The effects of age and sex were not significant as far as we used adolescent or young adult marmosets. Unexpectedly, experimental circumstance (in the colony or isolator) had only a subtle effect on performance. However, we found that marmosets from different families exhibited different learning process characteristics, suggesting some family effect on learning. Copyright © 2014 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Closely-related taxa influence woody species discrimination via DNA barcoding: evidence from global forest dynamics plots.

PubMed

Pei, Nancai; Erickson, David L; Chen, Bufeng; Ge, Xuejun; Mi, Xiangcheng; Swenson, Nathan G; Zhang, Jin-Long; Jones, Frank A; Huang, Chun-Lin; Ye, Wanhui; Hao, Zhanqing; Hsieh, Chang-Fu; Lum, Shawn; Bourg, Norman A; Parker, John D; Zimmerman, Jess K; McShea, William J; Lopez, Ida C; Sun, I-Fang; Davies, Stuart J; Ma, Keping; Kress, W John

2015-10-12

To determine how well DNA barcodes from the chloroplast region perform in forest dynamics plots (FDPs) from global CTFS-ForestGEO network, we analyzed DNA barcoding sequences of 1277 plant species from a wide phylogenetic range (3 FDPs in tropics, 5 in subtropics and 5 in temperate zone) and compared the rates of species discrimination (RSD). We quantified RSD by two DNA barcode combinations (rbcL + matK and rbcL + matK + trnH-psbA) using a monophyly-based method (GARLI). We defined two indexes of closely-related taxa (Gm/Gt and S/G ratios) and correlated these ratios with RSD. The combination of rbcL + matK averagely discriminated 88.65%, 83.84% and 72.51% at the local, regional and global scales, respectively. An additional locus trnH-psbA increased RSD by 2.87%, 1.49% and 3.58% correspondingly. RSD varied along a latitudinal gradient and were negatively correlated with ratios of closely-related taxa. Successes of species discrimination generally depend on scales in global FDPs. We suggested that the combination of rbcL + matK + trnH-psbA is currently applicable for DNA barcoding-based phylogenetic studies on forest communities.

Experiences of Transgender-Related Discrimination and Implications for Health: Results From the Virginia Transgender Health Initiative Study

PubMed Central

Reisner, Sari L.; Honnold, Julie A.; Xavier, Jessica

2013-01-01

Objectives. We examined relationships between social determinants of health and experiences of transgender-related discrimination reported by transgender people in Virginia. Methods. In 2005 through 2006, 387 self-identified transgender people completed a statewide health needs assessment; 350 who completed eligibility questions were included in this examination of factors associated with experiences of discrimination in health care, employment, or housing. We fit multivariate logistic regression models using generalized estimating equations to adjust for survey modality (online vs paper). Results. Of participants, 41% (n = 143) reported experiences of transgender-related discrimination. Factors associated with transgender-related discrimination were geographic context, gender (female-to male spectrum vs male-to-female spectrum), low socioeconomic status, being a racial/ethnic minority, not having health insurance, gender transition indicators (younger age at first transgender awareness), health care needed but unable to be obtained (hormone therapy and mental health services), history of violence (sexual and physical), substance use health behaviors (tobacco and alcohol), and interpersonal factors (family support and community connectedness). Conclusions. Findings suggest that transgender Virginians experience widespread discrimination in health care, employment, and housing. Multilevel interventions are needed for transgender populations, including legal protections and training for health care providers. PMID:23153142

Equal Educational Opportunity?

ERIC Educational Resources Information Center

Morris, Lorenzo

1980-01-01

Holds that the "Bakke" decision simply reaffirmed an insufficient commitment to equal opportunities for Blacks in higher education. Reviews several studies, including research conducted at the Institute for the Study of Educational Policy (ISEP) that has focused on the social and economic context of educational discrimination. (GC)

A Framework for Context Sensitive Risk-Based Access Control in Medical Information Systems

PubMed Central

Choi, Donghee; Kim, Dohoon; Park, Seog

2015-01-01

Since the access control environment has changed and the threat of insider information leakage has come to the fore, studies on risk-based access control models that decide access permissions dynamically have been conducted vigorously. Medical information systems should protect sensitive data such as medical information from insider threat and enable dynamic access control depending on the context such as life-threatening emergencies. In this paper, we suggest an approach and framework for context sensitive risk-based access control suitable for medical information systems. This approach categorizes context information, estimating and applying risk through context- and treatment-based permission profiling and specifications by expanding the eXtensible Access Control Markup Language (XACML) to apply risk. The proposed framework supports quick responses to medical situations and prevents unnecessary insider data access through dynamic access authorization decisions in accordance with the severity of the context and treatment. PMID:26075013

Research on dynamic performance design of mobile phone application based on context awareness

NASA Astrophysics Data System (ADS)

Bo, Zhang

2018-05-01

It aims to explore the dynamic performance of different mobile phone applications and the user's cognitive differences, reduce the cognitive burden, and enhance the sense of experience. By analyzing the dynamic design performance in four different interactive contexts, and constructing the framework of information service process in the interactive context perception and the two perception principles of the cognitive consensus between designer and user, and the two kinds of knowledge in accordance with the perception principles. The analysis of the context will help users sense the dynamic performance more intuitively, so that the details of interaction will be performed more vividly and smoothly, thus enhance user's experience in the interactive process. The common perception experience enables designers and users to produce emotional resonance in different interactive contexts, and help them achieve rapid understanding of interactive content and perceive the logic and hierarchy of the content and the structure, therefore the effectiveness of mobile applications will be improved.

Radiation injury vs. recurrent brain metastasis: combining textural feature radiomics analysis and standard parameters may increase 18F-FET PET accuracy without dynamic scans.

PubMed

Lohmann, Philipp; Stoffels, Gabriele; Ceccon, Garry; Rapp, Marion; Sabel, Michael; Filss, Christian P; Kamp, Marcel A; Stegmayr, Carina; Neumaier, Bernd; Shah, Nadim J; Langen, Karl-Josef; Galldiks, Norbert

2017-07-01

We investigated the potential of textural feature analysis of O-(2-[ 18 F]fluoroethyl)-L-tyrosine ( 18 F-FET) PET to differentiate radiation injury from brain metastasis recurrence. Forty-seven patients with contrast-enhancing brain lesions (n = 54) on MRI after radiotherapy of brain metastases underwent dynamic 18 F-FET PET. Tumour-to-brain ratios (TBRs) of 18 F-FET uptake and 62 textural parameters were determined on summed images 20-40 min post-injection. Tracer uptake kinetics, i.e., time-to-peak (TTP) and patterns of time-activity curves (TAC) were evaluated on dynamic PET data from 0-50 min post-injection. Diagnostic accuracy of investigated parameters and combinations thereof to discriminate between brain metastasis recurrence and radiation injury was compared. Diagnostic accuracy increased from 81 % for TBR mean alone to 85 % when combined with the textural parameter Coarseness or Short-zone emphasis. The accuracy of TBR max alone was 83 % and increased to 85 % after combination with the textural parameters Coarseness, Short-zone emphasis, or Correlation. Analysis of TACs resulted in an accuracy of 70 % for kinetic pattern alone and increased to 83 % when combined with TBR max . Textural feature analysis in combination with TBRs may have the potential to increase diagnostic accuracy for discrimination between brain metastasis recurrence and radiation injury, without the need for dynamic 18 F-FET PET scans. • Textural feature analysis provides quantitative information about tumour heterogeneity • Textural features help improve discrimination between brain metastasis recurrence and radiation injury • Textural features might be helpful to further understand tumour heterogeneity • Analysis does not require a more time consuming dynamic PET acquisition.

Body temperature as a conditional response measure for pavlovian fear conditioning.

PubMed

Godsil, B P; Quinn, J J; Fanselow, M S

2000-01-01

On six days rats were exposed to each of two contexts. They received an electric shock in one context and nothing in the other. Rats were tested later in each environment without shock. The rats froze and defecated more often in the shock-paired environment; they also exhibited a significantly larger elevation in rectal temperature in that environment. The rats discriminated between each context, and we suggest that the elevation in temperature is the consequence of associative learning. Thus, body temperature can be used as a conditional response measure in Pavlovian fear conditioning experiments that use footshock as the unconditional stimulus.

Activating Basic Category Exemplars in Sentence Contexts: A Dynamical Account

ERIC Educational Resources Information Center

Raczaszek-Leonardi, Joanna; Shapiro, Lewis P.; Tuller, Betty; Kelso, J. A. Scott

2008-01-01

This paper examines the influence of context on the processing of category names embedded in sentences. The investigation focuses on the nature of information available immediately after such a word is heard as well as on the dynamics of adaptation to context. An on-line method (Cross Modal Lexical Priming) was used to trace how this process…

Home-cage odors spatial cues elicit theta phase/gamma amplitude coupling between olfactory bulb and dorsal hippocampus.

PubMed

Pena, Roberta Ribas; Medeiros, Daniel de Castro; Guarnieri, Leonardo de Oliveira; Guerra, Julio Boriollo; Carvalho, Vinícius Rezende; Mendes, Eduardo Mazoni Andrade Marçal; Pereira, Grace Schenatto; Moraes, Márcio Flávio Dutra

2017-11-05

The brain oscillations may play a critical role in synchronizing neuronal assemblies in order to establish appropriate sensory-motor integration. In fact, studies have demonstrated phase-amplitude coupling of distinct oscillatory rhythms during cognitive processes. Here we investigated whether olfacto-hippocampal coupling occurs when mice are detecting familiar odors located in a spatially restricted area of a new context. The spatial olfactory task (SOT) was designed to expose mice to a new environment in which only one quadrant (target) contains odors provided by its own home-cage bedding. As predicted, mice showed a significant higher exploration preference to the target quadrant; which was impaired by olfactory epithelium lesion (ZnSO 4 ). Furthermore, mice were able to discriminate odors from a different cage and avoided the quadrant with predator odor 2,4,5-trimethylthiazoline (TMT), reinforcing the specificity of the SOT. The local field potential (LFP) analysis of non-lesioned mice revealed higher gamma activity (35-100Hz) in the main olfactory bulb (MOB) and a significant theta phase/gamma amplitude coupling between MOB and dorsal hippocampus, only during exploration of home-cage odors (i.e. in the target quadrant). Our results suggest that exploration of familiar odors in a new context involves dynamic coupling between the olfactory bulb and dorsal hippocampus. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Bodywork as systemic and inter-enactive competence: participatory process management in Feldenkrais® Method and Zen Shiatsu

PubMed Central

Kimmel, Michael; Irran, Christine; Luger, Martin A.

2014-01-01

Feldenkrais and Shiatsu enable somatic learning through continuous tactile coupling, a real-time interpersonal dynamic unfolding in a safe dyadic sphere. The first part of our micro-ethnographic study draws on process vignettes and subjective theories to demonstrate how bodywork is infused with systemic sensitivities and awareness for non-linear process management. Expressed in dynamic systems parlance, both disciplines foster metastability, adaptivity, and self-organization in the client's somato-personal system by progressively reconfiguring systemic dispositions, i.e., an attractor landscape. Doing so requires a keen embodied apperception of hierarchies of somato-systemic order. Bodyworkers learn to explore these in their eigenfunction (joints, muscles, fascia), discriminate coordinative organization in small ensembles, and monitor large-scale dynamic interplay. The practitioner's “extended body” reaching forth into the client's through a resonance loop eventually becomes part of this. Within a bodywork session, practitioners modulate this hierarchical functional architecture. Their ability for sensorially staying apace of systemic emergence allows them to respond to minute changes and customize reactions in a zone of proximal development (dynamic immediacy). They stimulate the client's system with a mix of perturbing and stabilizing interventions that oscillate between eigenfunctions and their coordinative integration. Practical knowledge for “soft-assembling” non-linear synergies is crucial for this (cumulative local effects, high-level functions “slaving” the system, etc.). The paper's second part inventorizes the bodyworker's operative tool-box—micro-skills providing the wherewithal for context-intelligent intervention. Practitioners deploy “educated senses” and a repertoire of hands-on techniques (grips, stretches, etc.) against a backdrop of somatic habits (proper posture, muscle activation, gaze patterns, etc.). At this level, our study addresses a host of micro-skills through the lens of enactive cognitive science. PMID:25628576

Assessment of change in dynamic psychotherapy.

PubMed

Høglend, P; Bøgwald, K P; Amlo, S; Heyerdahl, O; Sørbye, O; Marble, A; Sjaastad, M C; Bentsen, H

2000-01-01

Five scales have been developed to assess changes that are consistent with the therapeutic rationales and procedures of dynamic psychotherapy. Seven raters evaluated 50 patients before and 36 patients again after brief dynamic psychotherapy. A factor analysis indicated that the scales represent a dimension that is discriminable from general symptoms. A summary measure, Dynamic Capacity, was rated with acceptable reliability by a single rater. However, average scores of three raters were needed for good reliability of change ratings. The scales seem to be sufficiently fine-grained to capture statistically and clinically significant changes during brief dynamic psychotherapy.

Bias and discriminability during emotional signal detection in melancholic depression.

PubMed

Hyett, Matthew; Parker, Gordon; Breakspear, Michael

2014-04-27

Cognitive disturbances in depression are pernicious and so contribute strongly to the burden of the disorder. Cognitive function has been traditionally studied by challenging subjects with modality-specific psychometric tasks and analysing performance using standard analysis of variance. Whilst informative, such an approach may miss deeper perceptual and inferential mechanisms that potentially unify apparently divergent emotional and cognitive deficits. Here, we sought to elucidate basic psychophysical processes underlying the detection of emotionally salient signals across individuals with melancholic and non-melancholic depression. Sixty participants completed an Affective Go/No-Go (AGN) task across negative, positive and neutral target stimuli blocks. We employed hierarchical Bayesian signal detection theory (SDT) to model psychometric performance across three equal groups of those with melancholic depression, those with a non-melancholic depression and healthy controls. This approach estimated likely response profiles (bias) and perceptual sensitivity (discriminability). Differences in the means of these measures speak to differences in the emotional signal detection between individuals across the groups, while differences in the variance reflect the heterogeneity of the groups themselves. Melancholic participants showed significantly decreased sensitivity to positive emotional stimuli compared to those in the non-melancholic group, and also had a significantly lower discriminability than healthy controls during the detection of neutral signals. The melancholic group also showed significantly higher variability in bias to both positive and negative emotionally salient material. Disturbances of emotional signal detection in melancholic depression appear dependent on emotional context, being biased during the detection of positive stimuli, consistent with a noisier representation of neutral stimuli. The greater heterogeneity of the bias across the melancholic group is consistent with a more labile disorder (i.e. variable across the day). Future work will aim to understand how these findings reflect specific individual differences (e.g. prior cognitive biases) and clarify whether such biases change dynamically during cognitive tasks as internal models of the sensorium are refined and updated in response to experience.

Scale-Free Neural and Physiological Dynamics in Naturalistic Stimuli Processing

PubMed Central

Lin, Amy

2016-01-01

Abstract Neural activity recorded at multiple spatiotemporal scales is dominated by arrhythmic fluctuations without a characteristic temporal periodicity. Such activity often exhibits a 1/f-type power spectrum, in which power falls off with increasing frequency following a power-law function: P(f)∝1/fβ, which is indicative of scale-free dynamics. Two extensively studied forms of scale-free neural dynamics in the human brain are slow cortical potentials (SCPs)—the low-frequency (<5 Hz) component of brain field potentials—and the amplitude fluctuations of α oscillations, both of which have been shown to carry important functional roles. In addition, scale-free dynamics characterize normal human physiology such as heartbeat dynamics. However, the exact relationships among these scale-free neural and physiological dynamics remain unclear. We recorded simultaneous magnetoencephalography and electrocardiography in healthy subjects in the resting state and while performing a discrimination task on scale-free dynamical auditory stimuli that followed different scale-free statistics. We observed that long-range temporal correlation (captured by the power-law exponent β) in SCPs positively correlated with that of heartbeat dynamics across time within an individual and negatively correlated with that of α-amplitude fluctuations across individuals. In addition, across individuals, long-range temporal correlation of both SCP and α-oscillation amplitude predicted subjects’ discrimination performance in the auditory task, albeit through antagonistic relationships. These findings reveal interrelations among different scale-free neural and physiological dynamics and initial evidence for the involvement of scale-free neural dynamics in the processing of natural stimuli, which often exhibit scale-free dynamics. PMID:27822495

Minority Stress across the Career-Lifespan Trajectory

ERIC Educational Resources Information Center

Dispenza, Franco; Brown, Colton; Chastain, Taylor E.

2016-01-01

Sexual minority persons (e.g., lesbian, gay, bisexual, and queer) are likely to encounter "minority stress", such as discrimination, concealment, expectation of rejection, and internalized heterosexism. Minority stress occurs alongside one's lifespan and has considerable implications in the context of the career lifespan trajectory.…

Cultural Contexts of Exclusion: Women College Band Directors

ERIC Educational Resources Information Center

Gould, Elizabeth S.

2003-01-01

Despite gender affirmative employment practices, women constitute little more than 5% of all U.S. college band directors. Researchers have investigated this situation in terms of historical precedent, traditional socialization, discrimination, segregation, professional identity, and lack of role models. They have not, however, addressed the…

A Dual Standard for State Discrimination against Aliens.

ERIC Educational Resources Information Center

Harvard Law Review, 1979

1979-01-01

Attempts to resolve the dual standard in state treatment of aliens: minimal review of measures limiting participation in important "governmental functions" to citizens, but stringent scrutiny of measures disadvantaging aliens in other contexts. Available from Harvard Law Review Association, Gannett House, Cambridge, Mass. 02138; sc…

Intracellular signalling and plasma hormone profiles associated with the expression of unconditioned and conditioned fear and anxiety in female rats.

PubMed

Simone, Jonathan J; McCormick, Cheryl M

2017-02-01

There is considerable overlap in the neural regions and intracellular signalling pathways implicated in anxiety and fear, although less is known in females. Here, we investigated whether unconditioned and conditioned fear are associated with distinct patterns of expression of extracellular signal-regulated kinase-1 and -2 (ERK1/2), protein kinase B (Akt), and calcineurin (CaN) (proteins that are key regulators of the expression of and/or memory processes of fear and anxiety) in the dorsal and ventral hippocampus, medial prefrontal cortex, and amygdala (important regions in neural fear circuitry) of adult female rats, and used a multivariate approach to find patterns of signalling that might discriminate between the different states of fear. To isolate fear to the conditioned cue from generalized fear to the test context, rats were conditioned to an auditory tone (i.e. tone paired with footshock) and twenty-four hours later exposed to a novel context in the presence or absence of the conditioned cue. A third group that was exposed to the conditioning context without undergoing fear conditioning was included to control for unconditioned responses to the testing procedures, which are anxiogenic. A discriminate function analysis and MANOVA determined that hippocampal signalling best discriminated the three groups from each other. The addition of values for plasma concentrations of corticosterone and progesterone (as indices of activation of the hypothalamic-pituitary-adrenal stress axis) to statistical analyses increased the separation of the three groups. There was high degree of association among the three signalling molecules in the four brain regions within each group. There was an absence of the associations between the medial prefrontal cortex and the amygdala in the cued fear recall group that were strong for the non-conditioned group. These results demonstrated unique neuronal and hormonal signalling profiles associated with unconditioned, generalized, and conditioned fear expression in females and highlight the importance of including appropriate comparisons to best discriminate between these different emotional states. Copyright © 2016 Elsevier Inc. All rights reserved.

Auditory memory for timbre.

PubMed

McKeown, Denis; Wellsted, David

2009-06-01

Psychophysical studies are reported examining how the context of recent auditory stimulation may modulate the processing of new sounds. The question posed is how recent tone stimulation may affect ongoing performance in a discrimination task. In the task, two complex sounds occurred in successive intervals. A single target component of one complex was decreased (Experiments 1 and 2) or increased (Experiments 3, 4, and 5) in intensity on half of trials: The task was simply to identify those trials. Prior to each trial, a pure tone inducer was introduced either at the same frequency as the target component or at the frequency of a different component of the complex. Consistent with a frequency-specific form of disruption, discrimination performance was impaired when the inducing tone matched the frequency of the following decrement or increment. A timbre memory model (TMM) is proposed incorporating channel-specific interference allied to inhibition of attending in the coding of sounds in the context of memory traces of recent sounds. (c) 2009 APA, all rights reserved.

Valence modulates source memory for faces.

PubMed

Bell, Raoul; Buchner, Axel

2010-01-01

Previous studies in which the effects of emotional valence on old-new discrimination and source memory have been examined have yielded highly inconsistent results. Here, we present two experiments showing that old-new face discrimination was not affected by whether a face was associated with disgusting, pleasant, or neutral behavior. In contrast, source memory for faces associated with disgusting behavior (i.e., memory for the disgusting context in which the face was encountered) was consistently better than source memory for other types of faces. This data pattern replicates the findings of studies in which descriptions of cheating, neutral, and trustworthy behavior were used, which findings were previously ascribed to a highly specific cheater detection module. The present results suggest that the enhanced source memory for faces of cheaters is due to a more general source memory advantage for faces associated with negative or threatening contexts that may be instrumental in avoiding the negative consequences of encounters with persons associated with negative or threatening behaviors.

Depressive Symptoms and Externalizing Behaviors among Hispanic Immigrant Adolescents: Examining Longitudinal Effects of Cultural Stress

PubMed Central

Cano, Miguel Ángel; Schwartz, Seth J.; Castillo, Linda G.; Romero, Andrea J.; Huang, Shi; Lorenzo-Blanco, Elma I.; Unger, Jennifer B.; Zamboanga, Byron L.; Des Rosiers, Sabrina E.; Baezconde-Garbanati, Lourdes; Lizzi, Karina M.; Soto, Daniel W.; Oshri, Assaf; Villamar, Juan Andres; Pattarroyo, Monica; Szapocznik, José

2015-01-01

This study examined longitudinal effects of cultural stress (a latent factor comprised of bicultural stress, ethnic discrimination, and negative context of reception) on depressive symptoms and a range of externalizing behaviors among recently (≤5 years in the U.S. at baseline) immigrated Hispanic adolescents. A sample of 302 adolescents (53% boys; mean age 14.51 years) completed baseline measures of perceived ethnic discrimination, bicultural stress, and perceived negative context of reception; and outcome measures of depressive symptoms, cigarette smoking, alcohol use, aggressive behavior, and rule-breaking behavior six months post-baseline. A path analysis indicated that higher cultural stress scores predicted higher levels of all outcomes. These effects were consistent across genders, but varied by study site. Specifically, higher cultural stress scores increased depressive symptoms among participants in Miami, but not in Los Angeles. Findings suggest that cultural stress is a clinically relevant predictor of depressive symptoms and externalizing behaviors among Hispanic immigrant adolescents. PMID:25899132

Heparan Sulfates Support Pyramidal Cell Excitability, Synaptic Plasticity, and Context Discrimination

PubMed Central

Minge, Daniel; Senkov, Oleg; Kaushik, Rahul; Herde, Michel K.; Tikhobrazova, Olga; Wulff, Andreas B.; Mironov, Andrey; van Kuppevelt, Toin H.; Oosterhof, Arie; Kochlamazashvili, Gaga

2017-01-01

Abstract Heparan sulfate (HS) proteoglycans represent a major component of the extracellular matrix and are critical for brain development. However, their function in the mature brain remains to be characterized. Here, acute enzymatic digestion of HS side chains was used to uncover how HSs support hippocampal function in vitro and in vivo. We found that long-term potentiation (LTP) of synaptic transmission at CA3–CA1 Schaffer collateral synapses was impaired after removal of highly sulfated HSs with heparinase 1. This reduction was associated with decreased Ca2+ influx during LTP induction, which was the consequence of a reduced excitability of CA1 pyramidal neurons. At the subcellular level, heparinase treatment resulted in reorganization of the distal axon initial segment, as detected by a reduction in ankyrin G expression. In vivo, digestion of HSs impaired context discrimination in a fear conditioning paradigm and oscillatory network activity in the low theta band after fear conditioning. Thus, HSs maintain neuronal excitability and, as a consequence, support synaptic plasticity and learning. PMID:28119345

Unsupervised learning of discriminative edge measures for vehicle matching between nonoverlapping cameras.

PubMed

Shan, Ying; Sawhney, Harpreet S; Kumar, Rakesh

2008-04-01

This paper proposes a novel unsupervised algorithm learning discriminative features in the context of matching road vehicles between two non-overlapping cameras. The matching problem is formulated as a same-different classification problem, which aims to compute the probability of vehicle images from two distinct cameras being from the same vehicle or different vehicle(s). We employ a novel measurement vector that consists of three independent edge-based measures and their associated robust measures computed from a pair of aligned vehicle edge maps. The weight of each measure is determined by an unsupervised learning algorithm that optimally separates the same-different classes in the combined measurement space. This is achieved with a weak classification algorithm that automatically collects representative samples from same-different classes, followed by a more discriminative classifier based on Fisher' s Linear Discriminants and Gibbs Sampling. The robustness of the match measures and the use of unsupervised discriminant analysis in the classification ensures that the proposed method performs consistently in the presence of missing/false features, temporally and spatially changing illumination conditions, and systematic misalignment caused by different camera configurations. Extensive experiments based on real data of over 200 vehicles at different times of day demonstrate promising results.

Derivation of Human Chromatic Discrimination Ability from an Information-Theoretical Notion of Distance in Color Space.

PubMed

da Fonseca, María; Samengo, Inés

2016-12-01

The accuracy with which humans detect chromatic differences varies throughout color space. For example, we are far more precise when discriminating two similar orange stimuli than two similar green stimuli. In order for two colors to be perceived as different, the neurons representing chromatic information must respond differently, and the difference must be larger than the trial-to-trial variability of the response to each separate color. Photoreceptors constitute the first stage in the processing of color information; many more stages are required before humans can consciously report whether two stimuli are perceived as chromatically distinguishable. Therefore, although photoreceptor absorption curves are expected to influence the accuracy of conscious discriminability, there is no reason to believe that they should suffice to explain it. Here we develop information-theoretical tools based on the Fisher metric that demonstrate that photoreceptor absorption properties explain about 87% of the variance of human color discrimination ability, as tested by previous behavioral experiments. In the context of this theory, the bottleneck in chromatic information processing is determined by photoreceptor absorption characteristics. Subsequent encoding stages modify only marginally the chromatic discriminability at the photoreceptor level.

Sex differences in the acoustic structure of vowel-like grunt vocalizations in baboons and their perceptual discrimination by baboon listeners

NASA Astrophysics Data System (ADS)

Rendall, Drew; Owren, Michael J.; Weerts, Elise; Hienz, Robert D.

2004-01-01

This study quantifies sex differences in the acoustic structure of vowel-like grunt vocalizations in baboons (Papio spp.) and tests the basic perceptual discriminability of these differences to baboon listeners. Acoustic analyses were performed on 1028 grunts recorded from 27 adult baboons (11 males and 16 females) in southern Africa, focusing specifically on the fundamental frequency (F0) and formant frequencies. The mean F0 and the mean frequencies of the first three formants were all significantly lower in males than they were in females, more dramatically so for F0. Experiments using standard psychophysical procedures subsequently tested the discriminability of adult male and adult female grunts. After learning to discriminate the grunt of one male from that of one female, five baboon subjects subsequently generalized this discrimination both to new call tokens from the same individuals and to grunts from novel males and females. These results are discussed in the context of both the possible vocal anatomical basis for sex differences in call structure and the potential perceptual mechanisms involved in their processing by listeners, particularly as these relate to analogous issues in human speech production and perception.

The effects of morphine on fixed-interval patterning and temporal discrimination.

PubMed Central

Odum, A L; Schaal, D W

2000-01-01

Changes produced by drugs in response patterns under fixed-interval schedules of reinforcement have been interpreted to result from changes in temporal discrimination. To examine this possibility, this experiment determined the effects of morphine on the response patterning of 4 pigeons during a fixed-interval 1-min schedule of food delivery with interpolated temporal discrimination trials. Twenty of the 50 total intervals were interrupted by choice trials. Pecks to one key color produced food if the interval was interrupted after a short time (after 2 or 4.64 s). Pecks to another key color produced food if the interval was interrupted after a long time (after 24.99 or 58 s). Morphine (1.0 to 10.0 mg/kg) decreased the index of curvature (a measure of response patterning) during fixed intervals and accuracy during temporal discrimination trials. Accuracy was equally disrupted following short and long sample durations. Although morphine disrupted temporal discrimination in the context of a fixed-interval schedule, these effects are inconsistent with interpretations of the disruption of response patterning as a selective overestimation of elapsed time. The effects of morphine may be related to the effects of more conventional external stimuli on response patterning. PMID:11029024

“The only thing I wish I could change is that they treat us like people and not like animals”: Injury and Discrimination among Latino Farmworkers

PubMed Central

Snipes, Shedra A.; Cooper, Sharon P.; Shipp, Eva M.

2017-01-01

Objective This paper describes how perceived discrimination shapes the way Latino farmworkers encounter injuries and seek out treatment. Methods After 5 months of ethnographic fieldwork, 89 open-ended, semi-structured interviews were analyzed. NVivo was used to code and qualitatively organize the interviews and field notes. Finally, codes, notes, and co-occurring dynamics were used to iteratively assess the data for major themes. Results The primary source of perceived discrimination was the “boss” or farm owner. Immigrant status was also a significant influence on how farmworkers perceived the discrimination. Specifically, the ability to speak English and length of stay in the United States were related to stronger perceptions of discrimination. Finally, farm owners compelled their Latino employees to work through their injuries without treatment. Conclusions This ethnographic account brings attention to how discrimination and lack of worksite protections are implicated in farmworkers' injury experiences, and suggests the need for policies that better safeguards vulnerable workers. PMID:27749157

Discrimination of Human Forearm Motions on the Basis of Myoelectric Signals by Using Adaptive Fuzzy Inference System

NASA Astrophysics Data System (ADS)

Kiso, Atsushi; Seki, Hirokazu

This paper describes a method for discriminating of the human forearm motions based on the myoelectric signals using an adaptive fuzzy inference system. In conventional studies, the neural network is often used to estimate motion intention by the myoelectric signals and realizes the high discrimination precision. On the other hand, this study uses the fuzzy inference for a human forearm motion discrimination based on the myoelectric signals. This study designs the membership function and the fuzzy rules using the average value and the standard deviation of the root mean square of the myoelectric potential for every channel of each motion. In addition, the characteristics of the myoelectric potential gradually change as a result of the muscle fatigue. Therefore, the motion discrimination should be performed by taking muscle fatigue into consideration. This study proposes a method to redesign the fuzzy inference system such that dynamic change of the myoelectric potential because of the muscle fatigue will be taken into account. Some experiments carried out using a myoelectric hand simulator show the effectiveness of the proposed motion discrimination method.

EMPACT 3D: an advanced EMI discrimination sensor for CONUS and OCONUS applications

NASA Astrophysics Data System (ADS)

Keranen, Joe; Miller, Jonathan S.; Schultz, Gregory; Sander-Olhoeft, Morgan; Laudato, Stephen

2018-04-01

We recently developed a new, man-portable, electromagnetic induction (EMI) sensor designed to detect and classify small, unexploded sub-munitions and discriminate them from non-hazardous debris. The ability to distinguish innocuous metal clutter from potentially hazardous unexploded ordnance (UXO) and other explosive remnants of war (ERW) before excavation can significantly accelerate land reclamation efforts by eliminating time spent removing harmless scrap metal. The EMI sensor employs a multi-axis transmitter and receiver configuration to produce data sufficient for anomaly discrimination. A real-time data inversion routine produces intrinsic and extrinsic anomaly features describing the polarizability, location, and orientation of the anomaly under test. We discuss data acquisition and post-processing software development, and results from laboratory and field tests demonstrating the discrimination capability of the system. Data acquisition and real-time processing emphasize ease-of-use, quality control (QC), and display of discrimination results. Integration of the QC and discrimination methods into the data acquisition software reduces the time required between sensor data collection and the final anomaly discrimination result. The system supports multiple concepts of operations (CONOPs) including: 1) a non-GPS cued configuration in which detected anomalies are discriminated and excavated immediately following the anomaly survey; 2) GPS integration to survey multiple anomalies to produce a prioritized dig list with global anomaly locations; and 3) a dynamic mapping configuration supporting detection followed by discrimination and excavation of targets of interest.

Recognition in context: Implications for trade mark law.

PubMed

Humphreys, Michael S; McFarlane, Kimberley A; Burt, Jennifer S; Kelly, Sarah J; Weatherall, Kimberlee G; Burrell, Robert G

2017-10-01

Context effects in recognition have played a major role in evaluating theories of recognition. Understanding how context impacts recognition is also important for making sound trade mark law. Consumers attempting to discriminate between the brand they are looking for and a look-alike product often have to differentiate products which share a great deal of common context: positioning on the supermarket shelf, the type of store, aspects of the packaging, or brand claims. Trade mark and related laws aim to protect brands and reduce consumer confusion, but courts assessing allegations of trade mark infringement often lack careful empirical evidence concerning the impact of brand and context similarity, and, in the absence of such evidence, make assumptions about how consumers respond to brands that downplay the importance of context and focus on the similarity of registered marks. The experiments reported in this paper aimed to test certain common assumptions in trade mark law, providing evidence that shared context can cause mistakes even where brand similarity is low.

Treatment discrimination among assistant coaches of women's teams.

PubMed

Cunningham, George B; Sagas, Michael

2003-12-01

The purpose of this study was to examine organizational treatment discrimination (i.e., when members of a group receive fewer rewards, opportunities, or resources than they legitimately deserve based on job-related criteria) in the context of women's athletics. Data were collected from 170 assistant coaches of women's teams (i.e., women's basketball, softball, track, volleyball, soccer, and tennis). Results indicate that women's perceived work experiences and outcomes were comparable, and sometimes better, than those of men. We present competing explanations for this finding. First, it is possible that these women were not subjected to treatment discrimination. Alternatively, it is possible that this demonstrates the existence of the "paradox of the contented working woman." Additional analyses indicate that work experiences explained a large portion of the variance in organizational commitment and turnover intentions, thereby demonstrating their importance in the workplace.

Neighborhood Characteristics and Expectations of Racially Discriminatory Experiences Among African American Adolescents.

PubMed

Witherspoon, Dawn P; Seaton, Eleanor K; Rivas-Drake, Deborah

2016-09-01

This study examined how youth's neighborhood characteristics informed their expectations of racial discrimination concurrently and longitudinally. Secondary analyses were conducted on data from Waves 1, 3, 4, 5, and 6 of the Maryland Adolescent Development in Context Study, which permitted the examination of neighborhood influences among a socioeconomically diverse sample of African American parents and adolescents (n = 863; Mage  = 12.29). Youth exposed to more neighborhood disadvantage in seventh grade reported more negative concurrent neighborhood perceptions, which, in turn, predicted greater expectations of racial discrimination in eighth grade; youth's expectations remained stable into adulthood. Thus, support was found for the mediating role of youth's subjective neighborhood perceptions in the longitudinal relation between neighborhood structure and expectations of racial discrimination. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

Blood donation, deferral, and discrimination: FDA donor deferral policy for men who have sex with men.

PubMed

Galarneau, Charlene

2010-02-01

U.S. Food and Drug Administration (FDA) policy prohibits blood donation from men who have had sex with men (MSM) even one time since 1977. Growing moral criticism claims that this policy is discriminatory, a claim rejected by the FDA. An overview of U.S. blood donation, recent donor deferral policy, and the conventional ethical debate introduce the need for a different approach to analyzing discrimination claims. I draw on an institutional understanding of injustice to discern and describe five features of the MSM policy and its FDA context that contribute to its discriminatory effect. I note significant similarities in the 1980s policy of deferring Haitians, suggesting an historical pattern of discrimination in FDA deferral policy. Finally, I point to changes needed to move toward a nondiscriminatory deferral policy.

Coherent Multimodal Sensory Information Allows Switching between Gravitoinertial Contexts

PubMed Central

Barbiero, Marie; Rousseau, Célia; Papaxanthis, Charalambos; White, Olivier

2017-01-01

Whether the central nervous system is capable to switch between contexts critically depends on experimental details. Motor control studies regularly adopt robotic devices to perturb the dynamics of a certain task. Other approaches investigate motor control by altering the gravitoinertial context itself as in parabolic flights and human centrifuges. In contrast to conventional robotic experiments, where only the hand is perturbed, these gravitoinertial or immersive settings coherently plunge participants into new environments. However, radically different they are, perfect adaptation of motor responses are commonly reported. In object manipulation tasks, this translates into a good matching of the grasping force or grip force to the destabilizing load force. One possible bias in these protocols is the predictability of the forthcoming dynamics. Here we test whether the successful switching and adaptation processes observed in immersive environments are a consequence of the fact that participants can predict the perturbation schedule. We used a short arm human centrifuge to decouple the effects of space and time on the dynamics of an object manipulation task by adding an unnatural explicit position-dependent force. We created different dynamical contexts by asking 20 participants to move the object at three different paces. These contextual sessions were interleaved such that we could simulate concurrent learning. We assessed adaptation by measuring how grip force was adjusted to this unnatural load force. We found that the motor system can switch between new unusual dynamical contexts, as reported by surprisingly well-adjusted grip forces, and that this capacity is not a mere consequence of the ability to predict the time course of the upcoming dynamics. We posit that a coherent flow of multimodal sensory information born in a homogeneous milieu allows switching between dynamical contexts. PMID:28553233

Dynamic Positron Emission Tomography [PET] in Man Using Small Bismuth Germanate Crystals

DOE R&D Accomplishments Database

Derenzo, S. E.; Budinger, T. F.; Huesman, R. H.; Cahoon, J. L.

1982-04-01

Primary considerations for the design of positron emission tomographs for medical studies in humans are the need for high imaging sensitivity, whole organ coverage, good spatial resolution, high maximum data rates, adequate spatial sampling with minimum mechanical motion, shielding against out of plane activity, pulse height discrimination against scattered photons, and timing discrimination against accidental coincidences. We discuss the choice of detectors, sampling motion, shielding, and electronics to meet these objectives.

Lower pitch is larger, yet falling pitches shrink.

PubMed

Eitan, Zohar; Schupak, Asi; Gotler, Alex; Marks, Lawrence E

2014-01-01

Experiments using diverse paradigms, including speeded discrimination, indicate that pitch and visually-perceived size interact perceptually, and that higher pitch is congruent with smaller size. While nearly all of these studies used static stimuli, here we examine the interaction of dynamic pitch and dynamic size, using Garner's speeded discrimination paradigm. Experiment 1 examined the interaction of continuous rise/fall in pitch and increase/decrease in object size. Experiment 2 examined the interaction of static pitch and size (steady high/low pitches and large/small visual objects), using an identical procedure. Results indicate that static and dynamic auditory and visual stimuli interact in opposite ways. While for static stimuli (Experiment 2), higher pitch is congruent with smaller size (as suggested by earlier work), for dynamic stimuli (Experiment 1), ascending pitch is congruent with growing size, and descending pitch with shrinking size. In addition, while static stimuli (Experiment 2) exhibit both congruence and Garner effects, dynamic stimuli (Experiment 1) present congruence effects without Garner interference, a pattern that is not consistent with prevalent interpretations of Garner's paradigm. Our interpretation of these results focuses on effects of within-trial changes on processing in dynamic tasks and on the association of changes in apparent size with implied changes in distance. Results suggest that static and dynamic stimuli can differ substantially in their cross-modal mappings, and may rely on different processing mechanisms.

Bologna in Context: A Horizontal Perspective on the Dynamics of Governance Sites for a Europe of Knowledge

ERIC Educational Resources Information Center

Gornitzka, Ase

2010-01-01

This article presents a horizontal perspective on the dynamics of governance sites currently active for the European of Knowledge and places the Bologna process in this wider European level context. It introduces two dynamics of change in political organisation: (a) institutional differentiation and specialisation and (b) the interaction between…

To Learn and to Construct Knowledge in the Context of Work with Adult Education: A Portuguese Case Study

ERIC Educational Resources Information Center

Loureiro, Armando; Caria, Telmo H.

2013-01-01

Work contexts are frequently referred to as spaces of learning and production of individual and/or collective knowledge. In such contexts specific dynamics are developed which cause the processes of learning and of knowledge production to have particularities. This paper aims at accounting for some dynamics that are associated with those…

Metadata behind the Interoperability of Wireless Sensor Networks

PubMed Central

Ballari, Daniela; Wachowicz, Monica; Callejo, Miguel Angel Manso

2009-01-01

Wireless Sensor Networks (WSNs) produce changes of status that are frequent, dynamic and unpredictable, and cannot be represented using a linear cause-effect approach. Consequently, a new approach is needed to handle these changes in order to support dynamic interoperability. Our approach is to introduce the notion of context as an explicit representation of changes of a WSN status inferred from metadata elements, which in turn, leads towards a decision-making process about how to maintain dynamic interoperability. This paper describes the developed context model to represent and reason over different WSN status based on four types of contexts, which have been identified as sensing, node, network and organisational contexts. The reasoning has been addressed by developing contextualising and bridges rules. As a result, we were able to demonstrate how contextualising rules have been used to reason on changes of WSN status as a first step towards maintaining dynamic interoperability. PMID:22412330

Metadata behind the Interoperability of Wireless Sensor Networks.

PubMed

Ballari, Daniela; Wachowicz, Monica; Callejo, Miguel Angel Manso

2009-01-01

Wireless Sensor Networks (WSNs) produce changes of status that are frequent, dynamic and unpredictable, and cannot be represented using a linear cause-effect approach. Consequently, a new approach is needed to handle these changes in order to support dynamic interoperability. Our approach is to introduce the notion of context as an explicit representation of changes of a WSN status inferred from metadata elements, which in turn, leads towards a decision-making process about how to maintain dynamic interoperability. This paper describes the developed context model to represent and reason over different WSN status based on four types of contexts, which have been identified as sensing, node, network and organisational contexts. The reasoning has been addressed by developing contextualising and bridges rules. As a result, we were able to demonstrate how contextualising rules have been used to reason on changes of WSN status as a first step towards maintaining dynamic interoperability.

Dynamic access control model for privacy preserving personalized healthcare in cloud environment.

PubMed

Son, Jiseong; Kim, Jeong-Dong; Na, Hong-Seok; Baik, Doo-Kwon

2015-01-01

When sharing and storing healthcare data in a cloud environment, access control is a central issue for preserving data privacy as a patient's personal health data may be accessed without permission from many stakeholders. Specifically, dynamic authorization for the access of data is required because personal health data is stored in cloud storage via wearable devices. Therefore, we propose a dynamic access control model for preserving the privacy of personal healthcare data in a cloud environment. The proposed model considers context information for dynamic access. According to the proposed model, access control can be dynamically determined by changing the context information; this means that even for a subject with the same role in the cloud, access permission is defined differently depending on the context information and access condition. Furthermore, we experiment the ability of the proposed model to provide correct responses by representing a dynamic access decision with real-life personalized healthcare system scenarios.

Potential Policies and Laws to Prohibit Weight Discrimination: Public Views from 4 Countries

PubMed Central

Puhl, Rebecca M; Latner, Janet D; O’brien, Kerry S; Luedicke, Joerg; Danielsdottir, Sigrun; Salas, Ximena Ramos

2015-01-01

Context People viewed as “overweight” or “obese” are vulnerable to weight-based discrimination, creating inequities and adverse health outcomes. Given the high rates of obesity recorded globally, studies documenting weight discrimination in multiple countries, and an absence of legislation to address this form of discrimination, research examining policy remedies across different countries is needed. Our study provides the first multinational examination of public support for policies and legislation to prohibit weight discrimination. Methods Identical online surveys were completed by 2,866 adults in the United States, Canada, Australia, and Iceland. We assessed public support for potential laws to prohibit weight-based discrimination, such as adding body weight to existing civil rights statutes, extending disability protections to persons with obesity, and instituting legal measures to prohibit employers from discriminating against employees because of body weight. We examined sociodemographic and weight-related characteristics predicting support for antidiscrimination policies, and the differences in these patterns across countries. Findings The majority of participants in the United States, Canada, and Australia agreed that their government should have specific laws in place to prohibit weight discrimination. At least two-thirds of the participants in all 4 countries expressed support for policies that would make it illegal for employers to refuse to hire, assign lower wages, deny promotions, or terminate qualified employees because of body weight. Women and participants with higher body weight expressed more support for antidiscrimination measures. Beliefs about the causes of obesity were also related to support for these laws. Conclusions Public support for legal measures to prohibit weight discrimination can be found in the United States, Canada, Australia, and Iceland, especially for laws to remedy this discrimination in employment. Our findings provide important information for policymakers and interest groups both nationally and internationally and can help guide discussions about policy priorities to reduce inequities resulting from weight discrimination. PMID:26626983

Effects of D-cycloserine on the extinction of appetitive operant learning.

PubMed

Vurbic, Drina; Gold, Benjamin; Bouton, Mark E

2011-08-01

Four experiments with rat subjects examined whether D-cycloserine (DCS), a partial NMDA agonist, facilitates the extinction of operant lever-pressing reinforced by food. Previous research has demonstrated that DCS facilitates extinction learning with methods that involve Pavlovian extinction. In the current experiments, operant conditioning occurred in Context A, extinction in Context B, and then testing occurred in both the extinction and conditioning contexts. Experiments 1A and 1B tested the effects of three doses of DCS (5, 15, and 30 mg/kg) on the extinction of lever pressing trained as a free operant. Experiment 2 examined their effects when extinction of the free operant was conducted in the presence of nonresponse-contingent deliveries of the reinforcer (that theoretically reduced the role of generalization decrement in suppressing responding). Experiment 3 examined their effects on extinction of a discriminated operant, that is, one that had been reinforced in the presence of a discriminative stimulus, but not in its absence. A strong ABA renewal effect was observed in all four experiments during testing. However, despite the use of DCS doses and a drug administration procedure that facilitates the extinction of Pavlovian learning, there was no evidence in any experiment that DCS facilitated operant extinction learning assessed in either the extinction or the conditioning context. DCS may primarily facilitate learning processes that underlie Pavlovian, rather than purely operant, extinction. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

Relationship between Auditory and Cognitive Abilities in Older Adults

PubMed Central

Sheft, Stanley

2015-01-01

Objective The objective was to evaluate the association of peripheral and central hearing abilities with cognitive function in older adults. Methods Recruited from epidemiological studies of aging and cognition at the Rush Alzheimer’s Disease Center, participants were a community-dwelling cohort of older adults (range 63–98 years) without diagnosis of dementia. The cohort contained roughly equal numbers of Black (n=61) and White (n=63) subjects with groups similar in terms of age, gender, and years of education. Auditory abilities were measured with pure-tone audiometry, speech-in-noise perception, and discrimination thresholds for both static and dynamic spectral patterns. Cognitive performance was evaluated with a 12-test battery assessing episodic, semantic, and working memory, perceptual speed, and visuospatial abilities. Results Among the auditory measures, only the static and dynamic spectral-pattern discrimination thresholds were associated with cognitive performance in a regression model that included the demographic covariates race, age, gender, and years of education. Subsequent analysis indicated substantial shared variance among the covariates race and both measures of spectral-pattern discrimination in accounting for cognitive performance. Among cognitive measures, working memory and visuospatial abilities showed the strongest interrelationship to spectral-pattern discrimination performance. Conclusions For a cohort of older adults without diagnosis of dementia, neither hearing thresholds nor speech-in-noise ability showed significant association with a summary measure of global cognition. In contrast, the two auditory metrics of spectral-pattern discrimination ability significantly contributed to a regression model prediction of cognitive performance, demonstrating association of central auditory ability to cognitive status using auditory metrics that avoided the confounding effect of speech materials. PMID:26237423

Correlates of depressive symptoms among North Korean refugees adapting to South Korean society: the moderating role of perceived discrimination.

PubMed

Um, Mee Young; Chi, Iris; Kim, Hee Jin; Palinkas, Lawrence A; Kim, Jae Yop

2015-04-01

Although the prevalence of depressive disorders among North Korean (NK) refugees living in South Korea has been reported to be twice the rate of their South Korean counterparts, little is known about the correlates of depressive symptoms among this population. Despite their escape from a politically and economically repressive setting, NK refugees continue to face multidimensional hardships during their adaptation process in South Korea, which can adversely affect their mental health. However, to our knowledge, no empirical research exists to date on depressive symptoms in the context of adaptation or perceived discrimination among NK refugees. To fill this gap, this study used a sample of 261 NK refugees in South Korea from the 2010 National Survey on Family Violence to examine associations between sociocultural adaptation, perceived discrimination, and depressive symptoms, as well as the moderation effect of discrimination on adaptation to depressive symptoms. We found that poor sociocultural adaptation and perception of discrimination were associated with increased levels of depressive symptoms. Perception of discrimination attenuated the association between better adaptation and fewer depressive symptoms, when compared to no perception of discrimination. These findings highlight the need to improve NK refugees' adaptation and integration as well as their psychological well-being in a culturally sensitive and comprehensive manner. They also underscore the importance of educating South Koreans to become accepting hosts who value diversity, yet in a homogeneous society. Copyright © 2015 Elsevier Ltd. All rights reserved.

Health care barriers, racism, and intersectionality in Australia.

PubMed

Bastos, João L; Harnois, Catherine E; Paradies, Yin C

2018-02-01

While racism has been shown to negatively affect health care quality, little is known about the extent to which racial discrimination works with and through gender, class, and sexuality to predict barriers to health care (e.g., perceived difficulty accessing health services). Additionally, most existing studies focus on racial disparities in the U.S. context, with few examining marginalized groups in other countries. To address these knowledge gaps, we analyze data from the 2014 Australian General Social Survey, a nationally representative survey of individuals aged 15 and older living in 12,932 private dwellings. Following an intersectional perspective, we estimate a series of multivariable logit regression models to assess three hypotheses: racial discrimination will be positively associated with perceived barriers to health care (H1); the effect of perceived racial discrimination will be particularly severe for women, sexual minorities, and low socio-economic status individuals (H2); and, in addition to racial discrimination, other forms of perceived discrimination will negatively impact perceived barriers to health care (H3). Findings show that perceptions of racial discrimination are significantly associated with perceived barriers to health care, though this relationship is not significantly stronger for low status groups. In addition, our analyses reveal that perceived racism and other forms of discrimination combine to predict perceived barriers to health care. Taken together, these results speak to the benefits of an intersectional approach for examining racial inequalities in perceived access to health care. Copyright © 2017 Elsevier Ltd. All rights reserved.

Robust and Accurate Discrimination of Self/Non-Self Antigen Presentations by Regulatory T Cell Suppression.

PubMed

Furusawa, Chikara; Yamaguchi, Tomoyuki

The immune response by T cells usually discriminates self and non-self antigens, even though the negative selection of self-reactive T cells is imperfect and a certain fraction of T cells can respond to self-antigens. In this study, we construct a simple mathematical model of T cell populations to analyze how such self/non-self discrimination is possible. The results demonstrate that the control of the immune response by regulatory T cells enables a robust and accurate discrimination of self and non-self antigens, even when there is a significant overlap between the affinity distribution of T cells to self and non-self antigens. Here, the number of regulatory T cells in the system acts as a global variable controlling the T cell population dynamics. The present study provides a basis for the development of a quantitative theory for self and non-self discrimination in the immune system and a possible strategy for its experimental verification.

Robust and Accurate Discrimination of Self/Non-Self Antigen Presentations by Regulatory T Cell Suppression

PubMed Central

Furusawa, Chikara; Yamaguchi, Tomoyuki

2016-01-01

The immune response by T cells usually discriminates self and non-self antigens, even though the negative selection of self-reactive T cells is imperfect and a certain fraction of T cells can respond to self-antigens. In this study, we construct a simple mathematical model of T cell populations to analyze how such self/non-self discrimination is possible. The results demonstrate that the control of the immune response by regulatory T cells enables a robust and accurate discrimination of self and non-self antigens, even when there is a significant overlap between the affinity distribution of T cells to self and non-self antigens. Here, the number of regulatory T cells in the system acts as a global variable controlling the T cell population dynamics. The present study provides a basis for the development of a quantitative theory for self and non-self discrimination in the immune system and a possible strategy for its experimental verification. PMID:27668873

Reduced Data Dualscale Entropy Analysis of HRV Signals for Improved Congestive Heart Failure Detection

NASA Astrophysics Data System (ADS)

Kuntamalla, Srinivas; Lekkala, Ram Gopal Reddy

2014-10-01

Heart rate variability (HRV) is an important dynamic variable of the cardiovascular system, which operates on multiple time scales. In this study, Multiscale entropy (MSE) analysis is applied to HRV signals taken from Physiobank to discriminate Congestive Heart Failure (CHF) patients from healthy young and elderly subjects. The discrimination power of the MSE method is decreased as the amount of the data reduces and the lowest amount of the data at which there is a clear discrimination between CHF and normal subjects is found to be 4000 samples. Further, this method failed to discriminate CHF from healthy elderly subjects. In view of this, the Reduced Data Dualscale Entropy Analysis method is proposed to reduce the data size required (as low as 500 samples) for clearly discriminating the CHF patients from young and elderly subjects with only two scales. Further, an easy to interpret index is derived using this new approach for the diagnosis of CHF. This index shows 100 % accuracy and correlates well with the pathophysiology of heart failure.

How to Teach Controversial Constitutional Issues Facing Women.

ERIC Educational Resources Information Center

Berry, Mary Frances

1988-01-01

Explains that teaching the historical context of women's legal issues allows future voters to make informed decisions. Suggests ways of including the Equal Rights Amendment, sexual harassment, sexual discrimination, and abortion in the high school curriculum. Recommends several anthologies of primary materials for teaching these issues. (LS)

Drama of the 80s (Booksearch).

ERIC Educational Resources Information Center

English Journal, 1990

1990-01-01

Recommends eight plays from the 1980s which will challenge the thinking of students with issues such as evolving independence of young people, growing up in the context of racism and discrimination, insights into the world of the deaf, and the suffering of humanity during the French Revolution. (MG)

Getting Personal? Student Talk about Racism

ERIC Educational Resources Information Center

Epstein, Shira Eve; Lipschultz, Jessica

2012-01-01

This research explores student responses to Beyond Today, an after school program that brings youth together from diverse urban neighborhoods to form a multiracial community. Through the enacted curriculum, Beyond Today facilitators scaffold opportunities for students to study race and racial discrimination in historical and contemporary contexts.…

Behavioral Mechanisms of Context Fear Generalization in Mice

ERIC Educational Resources Information Center

Huckleberry, Kylie A.; Ferguson, Laura B.; Drew, Michael R.

2016-01-01

There is growing interest in generalization of learned contextual fear, driven in part by the hypothesis that mood and anxiety disorders stem from impaired hippocampal mechanisms of fear generalization and discrimination. However, there has been relatively little investigation of the behavioral and procedural mechanisms that might control…

Amygdala lesions in rhesus monkeys fail to disrupt object choices based on internal context

PubMed Central

Rhodes, Sarah E. V.; Charles, David P.; Howland, Emily J.; Murray, Elisabeth A.

2012-01-01

We assessed the involvement of the amygdala in a task in which object choices were guided by internal context. Rhesus monkeys were trained on a biconditional discrimination whereby objects associated with food (but not water) were baited when the monkey was hungry, and objects associated with water (but not food) were baited when the monkey was thirsty. To solve this task monkeys were required to choose objects yielding the reward congruent with their internal motivational state. Lesions of the amygdala did not disrupt learning or performance of this task. We conclude that the involvement of the amygdala in selective-satiation tasks, which depends in part on a change in internal context, is not due to the amygdala playing a general role in representing, or using, internal context. PMID:22352788

Social Salience Discriminates Learnability of Contextual Cues in an Artificial Language

PubMed Central

Rácz, Péter; Hay, Jennifer B.; Pierrehumbert, Janet B.

2017-01-01

We investigate the learning of contextual meaning by adults in an artificial language. Contextual meaning here refers to the non-denotative contextual information that speakers attach to a linguistic construction. Through a series of short games, played online, we test how well adults can learn different contextual meanings for a word-formation pattern in an artificial language. We look at whether learning contextual meanings depends on the social salience of the context, whether our players interpret these contexts generally, and whether the learned meaning is generalized to new words. Our results show that adults are capable of learning contextual meaning if the context is socially salient, coherent, and interpretable. Once a contextual meaning is recognized, it is readily generalized to related forms and contexts. PMID:28194122

Three experimental approaches to measure the social context dependence of prejudice communication and discriminatory behavior.

PubMed

Beyer, Heiko; Liebe, Ulf

2015-01-01

Empirical research on discrimination is faced with crucial problems stemming from the specific character of its object of study. In democratic societies the communication of prejudices and other forms of discriminatory behavior is considered socially undesirable and depends on situational factors such as whether a situation is considered private or whether a discriminatory consensus can be assumed. Regular surveys thus can only offer a blurred picture of the phenomenon. But also survey experiments intended to decrease the social desirability bias (SDB) so far failed in systematically implementing situational variables. This paper introduces three experimental approaches to improve the study of discrimination and other topics of social (un-)desirability. First, we argue in favor of cognitive context framing in surveys in order to operationalize the salience of situational norms. Second, factorial surveys offer a way to take situational contexts and substitute behavior into account. And third, choice experiments - a rather new method in sociology - offer a more valid method of measuring behavioral characteristics compared to simple items in surveys. All three approaches - which may be combined - are easy to implement in large-scale surveys. Results of empirical studies demonstrate the fruitfulness of each of these approaches. Copyright © 2014 Elsevier Inc. All rights reserved.

'If you feel that nobody wants you you'll withdraw into your own': Gypsies/Travellers, networks and healthcare utilisation.

PubMed

Smith, David; Ruston, Annmarie

2013-11-01

Gypsies and Travellers are the unhealthiest group in British society, suffering from higher levels of physical and mental illness, lower life expectancy and with low levels of healthcare utilisation. They also continue to experience the highest level of prejudice and discrimination in society. While studies indicate that social networks play an important role in shaping health beliefs and the response to symptoms, evidence on the influence of networks on health is unclear and contradictory. This article draws on social network theory and research into the relation between discrimination and health to critically examine how networks mediate between collective experiences of racism and health-related behavior. Qualitative interviews with 39 adult Gypsies and Travellers were conducted in the South-East of England to explore the wider structural and institutional context and the influence those contexts play in shaping health beliefs and decisions whether to access formal health services. The findings indicate that the influence networks play in shaping health behaviour is dependent on the particular social context of the group and its status in relation to wider social structures, making generalization problematic. © 2013 The Authors. Sociology of Health & Illness © 2013 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

Symptom Assessment in Knee Osteoarthritis Needs to Account for Physical Activity Level

PubMed Central

Lo, Grace H.; McAlindon, Timothy E.; Hawker, Gillian A.; Driban, Jeffrey B.; Price, Lori Lyn; Song, Jing; Eaton, Charles B.; Hochberg, Marc C.; Jackson, Rebecca D.; Kwoh, C. Kent; Nevitt, Michael C.; Dunlop, Dorothy D.

2015-01-01

Objective Pain is not always correlated with radiographic osteoarthritis (OA) severity possibly because people modify activities to manage symptoms. Measures of symptoms that consider pain in the context of activity level may therefore provide greater discrimination than pain alone. Our objective was to compare discrimination of a measure of pain alone with combined measures of pain relative to physical activity across radiographic OA levels. Methods This is a cross-sectional study of the Osteoarthritis Initiative accelerometer substudy, including those with and without knee OA. Two composite pain and activity knee symptom (PAKS) scores were calculated as Western Ontario and McMaster (WOMAC) Universities Osteoarthritis Pain Scale plus one divided by physical activity measures (step and activity counts). Symptom score discrimination across Kellgren and Lawrence (KL) grades were evaluated using histograms and quantile regression. Results 1806 participants, mean age 65.1 (9.1) years, mean BMI 28.4 (4.8) kg/m2, and 55.6% female, were included. WOMAC, but not PAKS scores, exhibited a floor effect. Adjusted median WOMAC by KL grades 0 – 4 were 0, 0, 1, 1, and 3 respectively. Median PAKS1 and PAKS2 were 24.9, 26.0, 32.4, 46.1, 97.9, and 7.2, 7.2, 9.2, 12.9, 23.8, respectively. PAKS scores had more statistically significant comparisons between KL grades compared with WOMAC. Conclusions Symptom assessments incorporating pain and physical activity did not exhibit a floor effect and were better able to discriminate radiographic severity than pain alone, particularly in milder disease. Pain in the context of physical activity level should be used to assess knee OA symptoms. PMID:26407008

Sex differences in conditioned stimulus discrimination during context-dependent fear learning and its retrieval in humans: the role of biological sex, contraceptives and menstrual cycle phases

PubMed Central

Lonsdorf, Tina B.; Haaker, Jan; Schümann, Dirk; Sommer, Tobias; Bayer, Janine; Brassen, Stefanie; Bunzeck, Nico; Gamer, Matthias; Kalisch, Raffael

2015-01-01

Background Anxiety disorders are more prevalent in women than in men. Despite this sexual dimorphism, most experimental studies are conducted in male participants, and studies focusing on sex differences are sparse. In addition, the role of hormonal contraceptives and menstrual cycle phase in fear conditioning and extinction processes remain largely unknown. Methods We investigated sex differences in context-dependent fear acquisition and extinction (day 1) and their retrieval/expression (day 2). Skin conductance responses (SCRs), fear and unconditioned stimulus expectancy ratings were obtained. Results We included 377 individuals (261 women) in our study. Robust sex differences were observed in all dependent measures. Women generally displayed higher subjective ratings but smaller SCRs than men and showed reduced excitatory/inhibitory conditioned stimulus (CS+/CS−) discrimination in all dependent measures. Furthermore, women using hormonal contraceptives showed reduced SCR CS discrimination on day 2 than men and free-cycling women, while menstrual cycle phase had no effect. Limitations Possible limitations include the simultaneous testing of up to 4 participants in cubicles, which might have introduced a social component, and not assessing postexperimental contingency awareness. Conclusion The response pattern in women shows striking similarity to previously reported sex differences in patients with anxiety. Our results suggest that pronounced deficits in associative discrimination learning and subjective expression of safety information (CS− responses) might underlie higher prevalence and higher symptom rates seen in women with anxiety disorders. The data call for consideration of biological sex and hormonal contraceptive use in future studies and may suggest that targeting inhibitory learning during therapy might aid precision medicine. PMID:26107163

Acquisition of contextual discrimination involves the appearance of a RAS-GRF1/p38 mitogen-activated protein (MAP) kinase-mediated signaling pathway that promotes long term potentiation (LTP).

PubMed

Jin, Shan-Xue; Arai, Junko; Tian, Xuejun; Kumar-Singh, Rajendra; Feig, Larry A

2013-07-26

RAS-GRF1 is a guanine nucleotide exchange factor with the ability to activate RAS and RAC GTPases in response to elevated calcium levels. We previously showed that beginning at 1 month of age, RAS-GRF1 mediates NMDA-type glutamate receptor (NMDAR)-induction of long term depression in the CA1 region of the hippocampus of mice. Here we show that beginning at 2 months of age, when mice first acquire the ability to discriminate between closely related contexts, RAS-GRF1 begins to contribute to the induction of long term potentiation (LTP) in the CA1 hippocampus by mediating the action of calcium-permeable, AMPA-type glutamate receptors (CP-AMPARs). Surprisingly, LTP induction by CP-AMPARs through RAS-GRF1 occurs via activation of p38 MAP kinase rather than ERK MAP kinase, which has more frequently been linked to LTP. Moreover, contextual discrimination is blocked by knockdown of Ras-Grf1 expression specifically in the CA1 hippocampus, infusion of a p38 MAP kinase inhibitor into the CA1 hippocampus, or the injection of an inhibitor of CP-AMPARs. These findings implicate the CA1 hippocampus in the developmentally dependent capacity to distinguish closely related contexts through the appearance of a novel LTP-supporting signaling pathway.

Dendrites, deep learning, and sequences in the hippocampus.

PubMed

Bhalla, Upinder S

2017-10-12

The hippocampus places us both in time and space. It does so over remarkably large spans: milliseconds to years, and centimeters to kilometers. This works for sensory representations, for memory, and for behavioral context. How does it fit in such wide ranges of time and space scales, and keep order among the many dimensions of stimulus context? A key organizing principle for a wide sweep of scales and stimulus dimensions is that of order in time, or sequences. Sequences of neuronal activity are ubiquitous in sensory processing, in motor control, in planning actions, and in memory. Against this strong evidence for the phenomenon, there are currently more models than definite experiments about how the brain generates ordered activity. The flip side of sequence generation is discrimination. Discrimination of sequences has been extensively studied at the behavioral, systems, and modeling level, but again physiological mechanisms are fewer. It is against this backdrop that I discuss two recent developments in neural sequence computation, that at face value share little beyond the label "neural." These are dendritic sequence discrimination, and deep learning. One derives from channel physiology and molecular signaling, the other from applied neural network theory - apparently extreme ends of the spectrum of neural circuit detail. I suggest that each of these topics has deep lessons about the possible mechanisms, scales, and capabilities of hippocampal sequence computation. © 2017 Wiley Periodicals, Inc.

Unconscious Local Motion Alters Global Image Speed

PubMed Central

Khuu, Sieu K.; Chung, Charles Y. L.; Lord, Stephanie; Pearson, Joel

2014-01-01

Accurate motion perception of self and object speed is crucial for successful interaction in the world. The context in which we make such speed judgments has a profound effect on their accuracy. Misperceptions of motion speed caused by the context can have drastic consequences in real world situations, but they also reveal much about the underlying mechanisms of motion perception. Here we show that motion signals suppressed from awareness can warp simultaneous conscious speed perception. In Experiment 1, we measured global speed discrimination thresholds using an annulus of 8 local Gabor elements. We show that physically removing local elements from the array attenuated global speed discrimination. However, removing awareness of the local elements only had a small effect on speed discrimination. That is, unconscious local motion elements contributed to global conscious speed perception. In Experiment 2 we measured the global speed of the moving Gabor patterns, when half the elements moved at different speeds. We show that global speed averaging occurred regardless of whether local elements were removed from awareness, such that the speed of invisible elements continued to be averaged together with the visible elements to determine the global speed. These data suggest that contextual motion signals outside of awareness can both boost and affect our experience of motion speed, and suggest that such pooling of motion signals occurs before the conscious extraction of the surround motion speed. PMID:25503603

Acquisition of Contextual Discrimination Involves the Appearance of a RAS-GRF1/p38 Mitogen-activated Protein (MAP) Kinase-mediated Signaling Pathway That Promotes Long Term Potentiation (LTP)*

PubMed Central

Jin, Shan-Xue; Arai, Junko; Tian, Xuejun; Kumar-Singh, Rajendra; Feig, Larry A.

2013-01-01

RAS-GRF1 is a guanine nucleotide exchange factor with the ability to activate RAS and RAC GTPases in response to elevated calcium levels. We previously showed that beginning at 1 month of age, RAS-GRF1 mediates NMDA-type glutamate receptor (NMDAR)-induction of long term depression in the CA1 region of the hippocampus of mice. Here we show that beginning at 2 months of age, when mice first acquire the ability to discriminate between closely related contexts, RAS-GRF1 begins to contribute to the induction of long term potentiation (LTP) in the CA1 hippocampus by mediating the action of calcium-permeable, AMPA-type glutamate receptors (CP-AMPARs). Surprisingly, LTP induction by CP-AMPARs through RAS-GRF1 occurs via activation of p38 MAP kinase rather than ERK MAP kinase, which has more frequently been linked to LTP. Moreover, contextual discrimination is blocked by knockdown of Ras-Grf1 expression specifically in the CA1 hippocampus, infusion of a p38 MAP kinase inhibitor into the CA1 hippocampus, or the injection of an inhibitor of CP-AMPARs. These findings implicate the CA1 hippocampus in the developmentally dependent capacity to distinguish closely related contexts through the appearance of a novel LTP-supporting signaling pathway. PMID:23766509

The dual effect of context on memory of related and unrelated themes: discrimination at encoding and cue at retrieval.

PubMed

Levy-Gigi, Einat; Vakil, Eli

2012-01-01

The influence of contextual factors on encoding and retrieval in recognition memory was investigated using a retroactive interference paradigm. Participants were randomly assigned to four context conditions constructed by manipulating types of presentation modality (pictures vs words) for study, interference, and test stages, respectively (ABA, ABB, AAA, & AAB). In Experiment 1 we presented unrelated items in the study and interference stages, while in Experiment 2 each stage contained items from the same semantic category. The results demonstrate a dual role for context in memory processes-at encoding as well as at retrieval. In Experiment 1 there is a hierarchical order between the four context conditions, depending on both target-test and target-interference contextual similarity. Adding a categorical context in Experiment 2 helped to specify each list and therefore better distinguish between target and interferer information, and in some conditions compensated for their perceptual similarity.

MD simulations of ligand-bound and ligand-free aptamer: molecular level insights into the binding and switching mechanism of the add A-riboswitch.

PubMed

Sharma, Monika; Bulusu, Gopalakrishnan; Mitra, Abhijit

2009-09-01

Riboswitches are structural cis-acting genetic regulatory elements in 5' UTRs of mRNAs, consisting of an aptamer domain that regulates the behavior of an expression platform in response to its recognition of, and binding to, specific ligands. While our understanding of the ligand-bound structure of the aptamer domain of the adenine riboswitches is based on crystal structure data and is well characterized, understanding of the structure and dynamics of the ligand-free aptamer is limited to indirect inferences from physicochemical probing experiments. Here we report the results of 15-nsec-long explicit-solvent molecular dynamics simulations of the add A-riboswitch crystal structure (1Y26), both in the adenine-bound (CLOSED) state and in the adenine-free (OPEN) state. Root-mean-square deviation, root-mean-square fluctuation, dynamic cross-correlation, and backbone torsion angle analyses are carried out on the two trajectories. These, along with solvent accessible surface area analysis of the two average structures, are benchmarked against available experimental data and are shown to constitute the basis for obtaining reliable insights into the molecular level details of the binding and switching mechanism. Our analysis reveals the interaction network responsible for, and conformational changes associated with, the communication between the binding pocket and the expression platform. It further highlights the significance of a, hitherto unreported, noncanonical W:H trans base pairing between A73 and A24, in the OPEN state, and also helps us to propose a possibly crucial role of U51 in the context of ligand binding and ligand discrimination.

Raspberry, not a car: context predictability and a phonological advantage in early and late learners’ processing of speech in noise

PubMed Central

Gor, Kira

2014-01-01

Second language learners perform worse than native speakers under adverse listening conditions, such as speech in noise (SPIN). No data are available on heritage language speakers’ (early naturalistic interrupted learners’) ability to perceive SPIN. The current study fills this gap and investigates the perception of Russian speech in multi-talker babble noise by the matched groups of high- and low-proficiency heritage speakers (HSs) and late second language learners of Russian who were native speakers of English. The study includes a control group of Russian native speakers. It manipulates the noise level (high and low), and context cloze probability (high and low). The results of the SPIN task are compared to the tasks testing the control of phonology, AXB discrimination and picture-word discrimination, and lexical knowledge, a word translation task, in the same participants. The increased phonological sensitivity of HSs interacted with their ability to rely on top–down processing in sentence integration, use contextual cues, and build expectancies in the high-noise/high-context condition in a bootstrapping fashion. HSs outperformed oral proficiency-matched late second language learners on SPIN task and two tests of phonological sensitivity. The outcomes of the SPIN experiment support both the early naturalistic advantage and the role of proficiency in HSs. HSs’ ability to take advantage of the high-predictability context in the high-noise condition was mitigated by their level of proficiency. Only high-proficiency HSs, but not any other non-native group, took advantage of the high-predictability context that became available with better phonological processing skills in high-noise. The study thus confirms high-proficiency (but not low-proficiency) HSs’ nativelike ability to combine bottom–up and top–down cues in processing SPIN. PMID:25566130

Raspberry, not a car: context predictability and a phonological advantage in early and late learners' processing of speech in noise.

PubMed

Gor, Kira

2014-01-01

Second language learners perform worse than native speakers under adverse listening conditions, such as speech in noise (SPIN). No data are available on heritage language speakers' (early naturalistic interrupted learners') ability to perceive SPIN. The current study fills this gap and investigates the perception of Russian speech in multi-talker babble noise by the matched groups of high- and low-proficiency heritage speakers (HSs) and late second language learners of Russian who were native speakers of English. The study includes a control group of Russian native speakers. It manipulates the noise level (high and low), and context cloze probability (high and low). The results of the SPIN task are compared to the tasks testing the control of phonology, AXB discrimination and picture-word discrimination, and lexical knowledge, a word translation task, in the same participants. The increased phonological sensitivity of HSs interacted with their ability to rely on top-down processing in sentence integration, use contextual cues, and build expectancies in the high-noise/high-context condition in a bootstrapping fashion. HSs outperformed oral proficiency-matched late second language learners on SPIN task and two tests of phonological sensitivity. The outcomes of the SPIN experiment support both the early naturalistic advantage and the role of proficiency in HSs. HSs' ability to take advantage of the high-predictability context in the high-noise condition was mitigated by their level of proficiency. Only high-proficiency HSs, but not any other non-native group, took advantage of the high-predictability context that became available with better phonological processing skills in high-noise. The study thus confirms high-proficiency (but not low-proficiency) HSs' nativelike ability to combine bottom-up and top-down cues in processing SPIN.

How proteins bind to DNA: target discrimination and dynamic sequence search by the telomeric protein TRF1

PubMed Central

2017-01-01

Abstract Target search as performed by DNA-binding proteins is a complex process, in which multiple factors contribute to both thermodynamic discrimination of the target sequence from overwhelmingly abundant off-target sites and kinetic acceleration of dynamic sequence interrogation. TRF1, the protein that binds to telomeric tandem repeats, faces an intriguing variant of the search problem where target sites are clustered within short fragments of chromosomal DNA. In this study, we use extensive (>0.5 ms in total) MD simulations to study the dynamical aspects of sequence-specific binding of TRF1 at both telomeric and non-cognate DNA. For the first time, we describe the spontaneous formation of a sequence-specific native protein–DNA complex in atomistic detail, and study the mechanism by which proteins avoid off-target binding while retaining high affinity for target sites. Our calculated free energy landscapes reproduce the thermodynamics of sequence-specific binding, while statistical approaches allow for a comprehensive description of intermediate stages of complex formation. PMID:28633355

Formalization and analysis of reasoning by assumption.

PubMed

Bosse, Tibor; Jonker, Catholijn M; Treur, Jan

2006-01-02

This article introduces a novel approach for the analysis of the dynamics of reasoning processes and explores its applicability for the reasoning pattern called reasoning by assumption. More specifically, for a case study in the domain of a Master Mind game, it is shown how empirical human reasoning traces can be formalized and automatically analyzed against dynamic properties they fulfill. To this end, for the pattern of reasoning by assumption a variety of dynamic properties have been specified, some of which are considered characteristic for the reasoning pattern, whereas some other properties can be used to discriminate among different approaches to the reasoning. These properties have been automatically checked for the traces acquired in experiments undertaken. The approach turned out to be beneficial from two perspectives. First, checking characteristic properties contributes to the empirical validation of a theory on reasoning by assumption. Second, checking discriminating properties allows the analyst to identify different classes of human reasoners. 2006 Lawrence Erlbaum Associates, Inc.

How Molecular Size Impacts RMSD Applications in Molecular Dynamics Simulations.

PubMed

Sargsyan, Karen; Grauffel, Cédric; Lim, Carmay

2017-04-11

The root-mean-square deviation (RMSD) is a similarity measure widely used in analysis of macromolecular structures and dynamics. As increasingly larger macromolecular systems are being studied, dimensionality effects such as the "curse of dimensionality" (a diminishing ability to discriminate pairwise differences between conformations with increasing system size) may exist and significantly impact RMSD-based analyses. For such large bimolecular systems, whether the RMSD or other alternative similarity measures might suffer from this "curse" and lose the ability to discriminate different macromolecular structures had not been explicitly addressed. Here, we show such dimensionality effects for both weighted and nonweighted RMSD schemes. We also provide a mechanism for the emergence of the "curse of dimensionality" for RMSD from the law of large numbers by showing that the conformational distributions from which RMSDs are calculated become increasingly similar as the system size increases. Our findings suggest the use of weighted RMSD schemes for small proteins (less than 200 residues) and nonweighted RMSD for larger proteins when analyzing molecular dynamics trajectories.

Solidarity through shared disadvantage: Highlighting shared experiences of discrimination improves relations between stigmatized groups.

PubMed

Cortland, Clarissa I; Craig, Maureen A; Shapiro, Jenessa R; Richeson, Jennifer A; Neel, Rebecca; Goldstein, Noah J

2017-10-01

Intergroup relations research has largely focused on relations between members of dominant groups and members of disadvantaged groups. The small body of work examining intraminority intergroup relations, or relations between members of different disadvantaged groups, reveals that salient experiences of ingroup discrimination promote positive relations between groups that share a dimension of identity (e.g., 2 different racial minority groups) and negative relations between groups that do not share a dimension of identity (e.g., a racial minority group and a sexual minority group). In the present work, we propose that shared experiences of discrimination between groups that do not share an identity dimension can be used as a lever to facilitate positive intraminority intergroup relations. Five experiments examining relations among 4 different disadvantaged groups supported this hypothesis. Both blatant (Experiments 1 and 3) and subtle (Experiments 2, 3, and 4) connections to shared experiences of discrimination, or inducing a similarity-seeking mindset in the context of discrimination faced by one's ingroup (Experiment 5), increased support for policies benefiting the outgroup (Experiments 1, 2, and 4) and reduced intergroup bias (Experiments 3, 4, and 5). Taken together, these experiments provide converging evidence that highlighting shared experiences of discrimination can improve intergroup outcomes between stigmatized groups across dimensions of social identity. Implications of these findings for intraminority intergroup relations are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Perceived Discrimination and Ethnic Identity Among Breast Cancer Survivors

PubMed Central

Campesino, Maureen; Saenz, Delia S.; Choi, Myunghan; Krouse, Robert S.

2012-01-01

Purpose/Objectives To examine ethnic identity and sociodemographic factors in minority patients' perceptions of healthcare discrimination in breast cancer care. Design Mixed methods. Setting Participants' homes in the metropolitan areas of Phoenix and Tucson, AZ. Sample 39 women treated for breast cancer in the past six years: 15 monolingual Spanish-speaking Latinas, 15 English-speaking Latinas, and 9 African Americans. Methods Two questionnaires were administered. Individual interviews with participants were conducted by nurse researchers. Quantitative, qualitative, and matrix analytic methods were used. Main Research Variables Ethnic identity and perceptions of discrimination. Findings Eighteen women (46%) believed race and spoken language affected the quality of health care. Perceived disrespect from providers was attributed to participant's skin color, income level, citizenship status, and ability to speak English. Discrimination was more likely to be described in a primary care context, rather than cancer care. Ethnic identity and early-stage breast cancer diagnosis were the only study variables significantly associated with perceived healthcare discrimination. Conclusions This article describes the first investigation examining ethnic identity and perceived discrimination in cancer care delivery. Replication of this study with larger samples is needed to better understand the role of ethnic identity and cancer stage in perceptions of cancer care delivery. Implications for Nursing Identification of ethnic-specific factors that influence patient's perspectives and healthcare needs will facilitate development of more effective strategies for the delivery of cross-cultural patient-centered cancer care. PMID:22374505

Impression Management in the Job Interview: An Effective Way of Mitigating Discrimination against Older Applicants?

PubMed

Gioaba, Irina; Krings, Franciska

2017-01-01

The increasingly aging population in most industrialized societies, coupled with the rather age-diverse current workforce makes discrimination against older employees a prevalent issue, especially in employment contexts. This renders research on ways for reducing this type of discrimination a particularly pressing concern. Drawing on theories of social identity and impression management, our research examines the role of impression management, aimed at refuting common older worker stereotypes, in diminishing bias against older job applicants during the job interview. The study consisted in an experimental hiring simulation conducted on a sample of 515 undergraduate students. Results show that older applicants who used impression management to contradict common older worker stereotypes were perceived as more hirable than those who did not. However, despite this positive effect, discrimination persisted: older applicants were consistently rated as less hirable than their younger counterparts when displaying the same IM behavior. Taken together, this research demonstrates that older job seekers can indeed ameliorate biased interview outcomes by engaging in impression management targeting common age stereotypes; however, it also shows that this strategy is insufficient for overcoming age discrimination entirely. The current study has important implications for theory, by expanding research on the use of impression management in mitigating age discrimination, as well as for practice, by offering older employees a hands-on strategy to reduce bias and stereotyping against them.

Impression Management in the Job Interview: An Effective Way of Mitigating Discrimination against Older Applicants?

PubMed Central

Gioaba, Irina; Krings, Franciska

2017-01-01

The increasingly aging population in most industrialized societies, coupled with the rather age-diverse current workforce makes discrimination against older employees a prevalent issue, especially in employment contexts. This renders research on ways for reducing this type of discrimination a particularly pressing concern. Drawing on theories of social identity and impression management, our research examines the role of impression management, aimed at refuting common older worker stereotypes, in diminishing bias against older job applicants during the job interview. The study consisted in an experimental hiring simulation conducted on a sample of 515 undergraduate students. Results show that older applicants who used impression management to contradict common older worker stereotypes were perceived as more hirable than those who did not. However, despite this positive effect, discrimination persisted: older applicants were consistently rated as less hirable than their younger counterparts when displaying the same IM behavior. Taken together, this research demonstrates that older job seekers can indeed ameliorate biased interview outcomes by engaging in impression management targeting common age stereotypes; however, it also shows that this strategy is insufficient for overcoming age discrimination entirely. The current study has important implications for theory, by expanding research on the use of impression management in mitigating age discrimination, as well as for practice, by offering older employees a hands-on strategy to reduce bias and stereotyping against them. PMID:28559869

Health Care Engagement and Follow-up After Perceived Discrimination in Maternity Care.

PubMed

Attanasio, Laura; Kozhimannil, Katy B

2017-09-01

Negative experiences in the health care system, including perceived discrimination, can result in patient disengagement from health care. Four million US women give birth each year, and the perinatal period is a time of sustained interaction with the health care system, but potential consequences of negative experiences have not been examined in this context. We assessed whether perceived discrimination during the birth hospitalization were associated with postpartum follow-up care. Data were from the Listening to Mothers III survey, a nationally drawn sample of 2400 women with singleton births in US hospitals in 2011-2012. We used multivariate logistic regression to estimate adjusted odds of having a postpartum visit in the 8 weeks following birth by perceptions of discrimination due to (1) race/ethnicity; (2) insurance type; and (3) a difference of opinion with a provider about care. Women who experienced any of the 3 types of perceived discrimination had more than twice the odds of postpartum visit nonattendance (adjusted odds ratio=2.28, P=0.001), after adjusting for socioeconomic and medical characteristics. The postpartum visit is an opportunity for a patient and clinician to address continuing health problems following birth, discuss contraception, and screen for chronic disease. Forgoing this care may have negative health effects. The findings from this study underscore the need to reduce discrimination and improve maternity care experiences.

Critical consciousness, racial and gender discrimination, and HIV disease markers in African American women with HIV.

PubMed

Kelso, Gwendolyn A; Cohen, Mardge H; Weber, Kathleen M; Dale, Sannisha K; Cruise, Ruth C; Brody, Leslie R

2014-07-01

Critical consciousness, the awareness of social oppression, is important to investigate as a buffer against HIV disease progression in HIV-infected African American women in the context of experiences with discrimination. Critical consciousness comprises several dimensions, including social group identification, discontent with distribution of social power, rejection of social system legitimacy, and a collective action orientation. The current study investigated self-reported critical consciousness as a moderator of perceived gender and racial discrimination on HIV viral load and CD4+ cell count in 67 African American HIV-infected women. Higher critical consciousness was found to be related to higher likelihood of having CD4+ counts over 350 and lower likelihood of detectable viral load when perceived racial discrimination was high, as revealed by multiple logistic regressions that controlled for highly active antiretroviral therapy (HAART) adherence. Multiple linear regressions showed that at higher levels of perceived gender and racial discrimination, women endorsing high critical consciousness had a larger positive difference between nadir CD4+ (lowest pre-HAART) and current CD4+ count than women endorsing low critical consciousness. These findings suggest that raising awareness of social oppression to promote joining with others to enact social change may be an important intervention strategy to improve HIV outcomes in African American HIV-infected women who report experiencing high levels of gender and racial discrimination.

Critical Consciousness, Racial and Gender Discrimination, and HIV Disease Markers in African American Women with HIV

PubMed Central

Kelso, Gwendolyn A.; Cohen, Mardge H.; Weber, Kathleen M.; Dale, Sannisha K.; Cruise, Ruth C.; Brody, Leslie R.

2014-01-01

Critical consciousness, the awareness of social oppression, is important to investigate as a buffer against HIV disease progression in HIV-infected African American women in the context of experiences with discrimination. Critical consciousness comprises several dimensions, including social group identification, discontent with distribution of social power, rejection of social system legitimacy, and a collective action orientation. The current study investigated self-reported critical consciousness as a moderator of perceived gender and racial discrimination on HIV viral load and CD4+ cell count in 67 African American HIV-infected women. Higher critical consciousness was found to be related to higher likelihood of having CD4+ counts over 350 and lower likelihood of detectable viral load when perceived racial discrimination was high, as revealed by multiple logistic regressions that controlled for highly active antiretroviral therapy (HAART) adherence. Multiple linear regressions showed that at higher levels of perceived gender and racial discrimination, women endorsing high critical consciousness had a larger positive difference between nadir CD4+ (lowest pre-HAART) and current CD4+ count than women endorsing low critical consciousness. These findings suggest that raising awareness of social oppression to promote joining with others to enact social change may be an important intervention strategy to improve HIV outcomes in African American HIV-infected women who report experiencing high levels of gender and racial discrimination. PMID:24077930

A benefit of context reinstatement to recognition memory in aging: the role of familiarity processes.

PubMed

Ward, Emma V; Maylor, Elizabeth A; Poirier, Marie; Korko, Malgorzata; Ruud, Jens C M

2017-11-01

Reinstatement of encoding context facilitates memory for targets in young and older individuals (e.g., a word studied on a particular background scene is more likely to be remembered later if it is presented on the same rather than a different scene or no scene), yet older adults are typically inferior at recalling and recognizing target-context pairings. This study examined the mechanisms of the context effect in normal aging. Age differences in word recognition by context condition (original, switched, none, new), and the ability to explicitly remember target-context pairings were investigated using word-scene pairs (Experiment 1) and word-word pairs (Experiment 2). Both age groups benefited from context reinstatement in item recognition, although older adults were significantly worse than young adults at identifying original pairings and at discriminating between original and switched pairings. In Experiment 3, participants were given a three-alternative forced-choice recognition task that allowed older individuals to draw upon intact familiarity processes in selecting original pairings. Performance was age equivalent. Findings suggest that heightened familiarity associated with context reinstatement is useful for boosting recognition memory in aging.

Assessment of Change in Dynamic Psychotherapy

PubMed Central

Høglend, Per; Bøgwald, Kjell-Petter; Amlo, Svein; Heyerdahl, Oscar; Sørbye, Øystein; Marble, Alice; Sjaastad, Mary Cosgrove; Bentsen, Håvard

2000-01-01

Five scales have been developed to assess changes that are consistent with the therapeutic rationales and procedures of dynamic psychotherapy. Seven raters evaluated 50 patients before and 36 patients again after brief dynamic psychotherapy. A factor analysis indicated that the scales represent a dimension that is discriminable from general symptoms. A summary measure, Dynamic Capacity, was rated with acceptable reliability by a single rater. However, average scores of three raters were needed for good reliability of change ratings. The scales seem to be sufficiently fine-grained to capture statistically and clinically significant changes during brief dynamic psychotherapy. PMID:11069131

Simultaneous measurement of dynamic strain and temperature distribution using high birefringence PANDA fiber Bragg grating

NASA Astrophysics Data System (ADS)

Zhu, Mengshi; Murayama, Hideaki

2017-04-01

New approach in simultaneous measurement of dynamic strain and temperature has been done by using a high birefringence PANDA fiber Bragg grating sensor. By this technique, we have succeeded in discriminating dynamic strain and temperature distribution at the sampling rate of 800 Hz and the spatial resolution of 1 mm. The dynamic distribution of strain and temperature were measured with the deviation of 5mm spatially. In addition, we have designed an experimental setup by which we can apply quantitative dynamic strain and temperature distribution to the fiber under testing without bounding it to a specimen.

A Three-Question Framework to Facilitate Clinical Decision Making

ERIC Educational Resources Information Center

Sibold, Jeremy

2012-01-01

Context: Highly developed critical thinking and the ability to discriminate among many possible therapeutic interventions is a core behavior for the practicing athletic trainer. However, while athletic training students receive a great deal of clinically applicable information, many are not explicitly trained in efficient methods for channeling…

Features and Feedback: Enhancing Metamnemonic Knowledge at Retrieval Reduces Source-Monitoring Errors

ERIC Educational Resources Information Center

Lane, Sean M.; Roussel, Cristine C.; Villa, Diane; Morita, Shelby K.

2007-01-01

Three experiments explored the issue of whether enhanced metamnemonic knowledge at retrieval can improve participants' ability to make difficult source discriminations in the context of the eyewitness suggestibility paradigm. The 1st experiment documented differences in phenomenal experience between veridical and false memories. Experiment 2…

Analysis of Social Referencing Skills among Children with Autism

ERIC Educational Resources Information Center

Brim, Devorah; Townsend, Dawn Buffington; DeQuinzio, Jaime Ann; Poulson, Claire L.

2009-01-01

Social referencing, a form of nonverbal communication, involves seeking out discriminative stimuli provided by others about contingencies in an ambiguous context in order to respond in a manner that produces reinforcement. Although demonstrated by typically developing infants, social referencing is notably absent or impaired in individuals with…